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PSA

Prostate-specific antigen (PSA), also known as kallikrein-3 (KLK3), is a glycoprotein enzyme produced primarily by the epithelial cells of the prostate gland in males.^[1] This protein is normally present in semen at high concentrations but leaks into the bloodstream in small amounts, where elevated levels can indicate prostate abnormalities, including benign conditions like prostatitis or benign prostatic hyperplasia, as well as prostate cancer.^[2] Discovered through independent research efforts in the 1970s, PSA was first identified in prostatic tissue extracts around 1970, purified and characterized by 1979, and detected in serum by 1980, enabling its development as a clinical biomarker.^[3]^[4] The PSA blood test, introduced in the late 1980s, revolutionized prostate cancer screening by allowing non-invasive detection of potential malignancies through measurement of serum PSA concentrations, typically reported in nanograms per milliliter (ng/mL), with levels above 4 ng/mL often prompting further evaluation.^[5] Its adoption led to increased early-stage diagnoses and contributed to declining prostate cancer mortality rates in screened populations, as evidenced by large-scale studies showing reduced deaths from aggressive disease.^[6] However, PSA's sensitivity comes at the cost of specificity, as non-cancerous factors frequently elevate readings, resulting in false positives that drive unnecessary biopsies and anxiety.^[1] Debates over PSA screening intensified following randomized trials in the early 2000s, which highlighted risks of overdiagnosis and overtreatment of indolent tumors that may never cause harm, potentially leading to side effects from interventions like surgery or radiation without extending life.^[7]^[8] Guidelines from bodies like the U.S. Preventive Services Task Force have oscillated, initially recommending against routine screening in 2012 due to net harm concerns before moderating to shared decision-making in 2018, reflecting empirical data on both benefits for high-risk groups and limitations in broad application.^[9] Despite these issues, ongoing refinements, such as PSA velocity tracking or isoform ratios, aim to enhance accuracy, underscoring PSA's enduring role as the primary tool for prostate cancer risk stratification amid calls for personalized approaches over blanket dismissal.^[10]

Medicine

Prostate-specific antigen

Prostate-specific antigen (PSA) is a glycoprotein enzyme produced primarily by the epithelial cells of the prostate gland, where it functions to liquefy semen by cleaving seminal vesicle proteins.^[1] First identified in prostatic tissue extracts in 1970, PSA was purified and characterized in 1979, with its detection in serum reported in 1980. Clinical blood testing for PSA became available in the mid-1980s, initially approved by the U.S. Food and Drug Administration in 1986 for monitoring prostate cancer recurrence post-treatment, and later in 1994 for early detection screening.^[11] PSA levels are measured via immunoassay in nanograms per milliliter (ng/mL) of blood, with reference ranges increasing with age due to prostate growth: typically 0-2.5 ng/mL for men aged 40-49, 0-3.5 ng/mL for 50-59, 0-4.5 ng/mL for 60-69, and 0-6.5 ng/mL for 70 and older.^[12] To enhance specificity amid low positive predictive value (around 20-30% for total PSA 4-10 ng/mL), adjunct metrics include PSA density (total PSA divided by prostate volume via imaging) and free-to-total PSA ratio (percentage of unbound PSA, where lower ratios suggest higher cancer risk).^[13] Widespread PSA screening adoption in the 1990s correlated with stage migration—earlier detection of localized disease—and reductions in prostate cancer mortality, as evidenced by the European Randomized Study of Screening for Prostate Cancer (ERSPC), which reported a 20% relative reduction in deaths after 9 years of follow-up in screened versus unscreened men, with longer-term data confirming sustained benefits.^[14] In the U.S., PSA testing rates declined 46% from 2008 to 2020 amid guideline shifts emphasizing shared decision-making, but rebounded with a 21% increase from 2020 to 2022 following COVID-19 disruptions.^[15] These trends reflect causal evidence from randomized trials linking screening to decreased metastatic presentations, though absolute mortality benefits remain modest (e.g., 1 fewer death per 1,000 men screened over 13 years in ERSPC subsets).^[16] Debates persist over PSA's net utility due to overdiagnosis of indolent tumors—estimated at 20-50% of screen-detected cases based on autopsy prevalence of occult prostate cancer (30-50% in men over 70 dying of other causes)—and false positives from benign prostatic hyperplasia (BPH) or prostatitis, which elevate levels without malignancy in up to 75% of elevated readings.^[17] ^[18] Such issues drive overtreatment harms, including urinary incontinence (5-20% post-prostatectomy) and erectile dysfunction, prompting guidelines to weigh individual risks like family history over population-level screening. Empirical data underscore that while PSA enables mortality reductions via early intervention, its imperfect specificity necessitates multiparametric MRI or biomarkers to mitigate unnecessary biopsies, prioritizing causal harm-benefit ratios over unadjusted adoption.^[7]

Chemistry

Styrene-acrylonitrile copolymer

Styrene-acrylonitrile copolymer (SAN), also known as polystyrene-acrylonitrile, is a thermoplastic random copolymer synthesized from styrene and acrylonitrile monomers, typically comprising 70-75% styrene and 25-30% acrylonitrile by weight.^[19]^[20] This composition imparts enhanced properties over polystyrene alone, including greater rigidity, transparency, and resistance to chemicals such as oils and greases.^[19] SAN is produced primarily through free-radical polymerization methods, including emulsion, suspension, or mass polymerization processes, where the monomers are copolymerized in the presence of initiators like peroxides.^[21] The resulting amorphous polymer exhibits a glass transition temperature (Tg) of approximately 102-105°C, enabling dimensional stability at elevated temperatures without softening.^[22]^[23] Its mechanical properties include a tensile strength of around 70-80 MPa and good clarity due to the alternating copolymer structure, though it remains brittle compared to impact-modified variants.^[19] Developed commercially in the 1940s as an improvement over polystyrene for demanding applications, SAN gained widespread adoption by the 1950s for its balanced performance in rigid, glossy parts.^[24]^[25] Industrial uses include household appliances, kitchenware, battery cases, and automotive components, where its chemical resistance and processability via injection molding or extrusion are advantageous.^[19] SAN serves as a base resin in blends such as acrylonitrile-butadiene-styrene (ABS), where rubber grafting enhances impact strength without sacrificing core attributes like heat resistance.^[24] It maintains a stable position in the commodity thermoplastics market, with production focused on cost-effective, high-volume manufacturing rather than recent innovations.^[25]

Media and communications

Public service announcement

A public service announcement (PSA) is a non-commercial message disseminated through mass media or digital platforms to raise awareness about matters of public interest, such as health risks, safety protocols, environmental concerns, or social behaviors. These announcements typically feature concise messaging aimed at informing or persuading audiences to adopt specific actions, often sponsored by government agencies, nonprofits, or broadcasters fulfilling public interest obligations.^[26] In the United States, PSAs emerged during the 1940s amid World War II efforts to promote war bonds and civilian preparedness via radio broadcasts, evolving into postwar campaigns on topics like traffic safety and public health. The Federal Communications Commission (FCC) reinforced this through its public interest standard, requiring licensees to address community needs; under the fairness doctrine enacted in 1949 and repealed in 1987, stations were incentivized to air balanced public service content, including PSAs, to demonstrate equitable coverage of controversial issues.^[27] Post-deregulation via the Telecommunications Act of 1984 and subsequent FCC policies, PSA airtime became largely voluntary, shifting reliance to advertiser goodwill and, from the 2010s onward, social media platforms where hashtags like #PSA facilitate viral dissemination of short videos and infographics on issues from mental health to disaster preparedness.^[28] PSAs encompass diverse formats, ranging from 30-second television spots in the mid-20th century—such as anti-drunk driving campaigns by the Ad Council—to contemporary digital iterations like targeted social media ads or interactive apps. Notable examples include the CDC's Tips From Former Smokers campaign launched in 2012, which exposed over 450 million impressions and correlated with increased quitline calls and reduced relapse rates among viewers. Anti-smoking PSAs have shown some efficacy, with a study of state-sponsored youth-targeted ads linking a 100-ad annual increase to a 0.1 percentage point drop in youth smoking prevalence.^[29] ^[30] However, outcomes vary; the Drug Abuse Resistance Education (DARE) program's associated media efforts, emphasizing "just say no" messaging, demonstrated no long-term reduction in youth drug use per meta-analyses of randomized trials and longitudinal evaluations.^[31] Evidence on PSA effectiveness remains mixed, with meta-analyses indicating modest short-term gains in awareness but limited sustained behavioral change, particularly for complex issues like violence prevention or illicit drug use. A review of anti-drug PSAs found no significant overall impact on consumption in randomized trials, while observational data suggested inconsistent or even counterproductive effects in some cases. Proponents argue PSAs elevate issue salience and support quitting behaviors, as seen in tobacco control where public campaigns contributed to youth smoking rates falling from 36.4% in 1997 to 3.8% in 2021 amid multifaceted interventions.^[32] Critics, however, highlight causal attribution challenges, noting that isolated PSAs often fail to alter entrenched habits without complementary policies, and may foster complacency or unintended backlash; negative-framed messages, common in fear-based 1980s-2000s ads on drugs or AIDS, proved less persuasive than positive appeals in acceptance metrics.^[33] Politicized PSAs, such as the NFL's 2020 Super Bowl spot honoring Botham Jean to underscore "the human cost of police brutality," drew backlash for perceived selective outrage and hypocrisy, illustrating risks of advocacy-driven content alienating audiences and prioritizing narrative over evidence-based neutrality.^[34] Such critiques underscore preferences for individual agency and empirical validation over presumptive societal nudges, with studies emphasizing that efficacy hinges on message tailoring, repetition, and integration with enforceable measures rather than announcement alone.^[35]

Computing

Packet Switch Adapter

The Packet Switch Adapter (PSA) refers to specialized hardware interfaces developed in the late 1960s and early 1970s to connect host computers to packet-switched networks, particularly in the ARPANET project. These adapters implemented the BBN 1822 protocol, detailed in Bolt, Beranek and Newman Report 1822 from October 1970, enabling reliable data exchange between hosts and Interface Message Processors (IMPs), the ARPANET's core packet switches.^[36]^[37] The design addressed the need for adapting diverse host systems—such as the SDS Sigma 7 at UCLA—to the standardized IMP interface, supporting initial ARPANET connections starting in 1969.^[38] Key functions included packet buffering to manage transmission rates, error detection via checksums on message blocks, and protocol handling for control signals like leader readiness and end-of-message indicators. The 1822 interface supported variants for local hosts (up to 100 feet cable length) and distant hosts (up to 2,000 feet), using electrical signaling over twisted-pair or coaxial cables to transmit fixed-size packets of up to 1,024 eight-bit bytes.^[38]^[39] Flow control was enforced through mechanisms such as the Ready for Next Message (RFNM) acknowledgment, preventing host overload by coordinating with IMP buffering capacities of around 8,192 bytes per host channel.^[40] In broader telecom contexts, similar adapters facilitated connections to X.25-based networks standardized by the ITU in 1976, adapting asynchronous terminals or mainframes to virtual circuits for efficient, store-and-forward data routing. However, as TCP/IP protocols matured in the late 1970s and 1980s, PSAs were rendered obsolete by integrated network interface cards (NICs) and routers capable of direct layer-3 addressing, reducing reliance on dedicated hardware intermediaries.^[39] Remaining legacy uses in specialized telecom backbones dwindled by the 1990s amid IP dominance.^[41]

Portable Sound Association

The Portable Sound Association (PSA) is not documented in major industry records or public archives as a formal entity dedicated to portable audio standards. Searches across historical tech databases, audio engineering publications, and organizational registries yield no verifiable founding date, membership, or specific contributions to formats like AAC or MP3 player interoperability. Related efforts in the pre-smartphone era (roughly 1998–2010) focused on securing and standardizing digital audio for portable devices amid piracy concerns, exemplified by the Secure Digital Music Initiative (SDMI), launched in 1998 by the Recording Industry Association of America (RIAA) alongside hardware firms like Sony and Philips to enable protected playback across players supporting MP3 and emerging codecs. SDMI sought interoperability through cryptographic standards but dissolved by mid-2001 after technical challenges and lack of consensus prevented widespread adoption. Advanced Audio Coding (AAC), patented in 1997 by Fraunhofer IIS and collaborators including Dolby Laboratories, gained traction in portable players like the iPod (introduced 2001) for superior compression efficiency over MP3 at equivalent bitrates, supporting broader device compatibility without a singular association's oversight. Dedicated MP3 players peaked in popularity during the mid-2000s, with global sales in the millions annually, but declined sharply post-2010 as smartphones integrated audio playback, reducing standalone device shipments to approximately 250,000 units by 2022. Any niche group akin to a "Portable Sound Association" likely saw diminished relevance in this shift, supplanted by ecosystem standards from entities like the Bluetooth Special Interest Group and app-based streaming protocols.

Organizations

Automotive: PSA Group

The PSA Group (Peugeot Société Anonyme) emerged in 1976 from the acquisition by Peugeot S.A. of 89.95% of the shares in the bankrupt Citroën S.A., creating a unified French automotive entity focused on passenger cars, light commercial vehicles, and components.^[42] This merger consolidated production capabilities, enabling economies in engineering and supply chains, with the group later rebranding as Groupe PSA in 2016.^[43] Key models included the Peugeot 208, a B-segment subcompact hatchback introduced in 2012 as successor to the 207, and the 3008, a C-segment compact crossover SUV launched in 2008, both emphasizing efficient powertrains and modular platforms like the EMP2 architecture.^[44] Groupe PSA achieved prominence in diesel engine technology through its BlueHDi lineup, which integrated selective catalytic reduction (SCR) systems with urea injection, oxidation catalysts, and diesel particulate filters (DPF) to meet Euro 6 emissions standards, reducing nitrogen oxides (NOx) by up to 90% and particulate matter by 99.9% compared to prior generations.^[45] These engines, based on 1.6-liter and 2.0-liter displacements, powered models like the Peugeot 308 and Citroën C4, contributing to the group's leadership in low-emission diesel sales in Europe during the 2010s.^[46] Global vehicle sales peaked at 3.88 million units in 2018, reflecting strong European market share and expansion into regions like Latin America and Asia via partnerships such as with Dongfeng Motor in China.^[47] Despite these advances, the group encountered quality challenges, including a 2010 recall of approximately 97,000 Peugeot 107 and Citroën C1 vehicles produced at a shared Czech facility with Toyota, due to potential accelerator pedal sticking that could lead to unintended acceleration.^[48] Such incidents highlighted vulnerabilities in outsourced manufacturing and component reliability during the decade.^[49] Broader European Union regulations on emissions, safety, and electrification imposed escalating compliance costs—estimated to progressively burden the sector's R&D budgets—potentially hindering innovation in internal combustion efficiencies amid a mandated shift to battery-electric vehicles driven by policy targets rather than unproven long-term market demand.^[50]^[51] In January 2021, Groupe PSA completed a 50-50 merger with Fiat Chrysler Automobiles (FCA), forming Stellantis N.V. and generating synergies in purchasing, platforms, and electrification to counter global supply chain disruptions from events like the COVID-19 pandemic and semiconductor shortages.^[52] The combined entity reported adjusted operating margins of 5.5% to 7.5% for 2021, demonstrating post-merger resilience despite a 2019 sales dip to 3.49 million units for PSA alone.^[53] This integration preserved PSA's engineering heritage while addressing competitive pressures from Asian manufacturers unencumbered by equivalent regulatory loads.^[54]

Aviation: PSA Airlines

PSA Airlines is a regional airline based in the United States that operates flights on behalf of American Airlines under the American Eagle brand. Headquartered in Dayton, Ohio, with plans to relocate its headquarters to Charlotte, North Carolina, in January 2026, the carrier employs over 5,000 team members and maintains flight crew bases in Dayton (DAY), Washington, D.C. (DCA), Charlotte (CLT), Dallas/Fort Worth (DFW), and Philadelphia (PHL).^[55]^[56] The airline traces its origins to Vee Neal Airlines, founded in 1979, which evolved into Jetstream International Airlines before rebranding as PSA Airlines and commencing operations on November 1, 1995. As a wholly owned subsidiary of American Airlines Group, PSA functions within a regional model that relies on capacity purchase agreements with its parent, providing scheduled passenger service using fixed-fee contracts that mitigate direct exposure to fuel price fluctuations and demand variability.^[57]^[58] PSA operates an all-jet fleet composed exclusively of Mitsubishi Heavy Industries Regional Jet (MHI RJ) aircraft, specifically Bombardier CRJ-700 and CRJ-900 models, totaling 148 aircraft with an average age of 13.5 years as of October 2025. The carrier conducts more than 600 daily flights to nearly 100 destinations, primarily serving short-haul routes from major hubs including CLT, DFW, PHL, and DCA, with a focus on connecting smaller markets to American Airlines' network. In October 2024, PSA announced the addition of 14 CRJ-900 aircraft to its fleet, configured for 76 passengers in a dual-class layout, to support ongoing expansion.^[57]^[59]^[60]

Logistics: PSA International

PSA International Pte Ltd is a Singapore-headquartered multinational port operator focused on container terminals, marine services, and logistics, playing a pivotal role in global trade transshipment. Originally established on 1 April 1964 as the Port of Singapore Authority to oversee port development and operations amid Singapore's post-independence growth, the entity shifted to a commercial model through corporatization on 1 October 1997 as PSA Corporation Limited, becoming a wholly owned subsidiary of Temasek Holdings while retaining government linkages for strategic oversight.^[61]^[62] This structure separated regulatory functions to the Maritime and Port Authority of Singapore, allowing PSA to prioritize efficiency in handling rising container volumes, from the first container vessel in 1972 to surpassing 1 million TEUs by 1982 and 5 million TEUs by 1990.^[62] In Singapore, PSA integrates operations across terminals including Tanjong Pagar, Keppel, Brani, Pasir Panjang, and the phased Tuas Mega Port, with the latter designed for full automation and a capacity exceeding 65 million TEUs annually upon completion by the 2040s; existing city terminals are slated for relocation to Tuas by 2027. In 2024, PSA's Singapore facilities processed a record 40.9 million TEUs, up 5.5% from 2023, supporting the port's handling of nearly 20% of worldwide container transshipments through streamlined inter-terminal transfers and digital integration. Globally, PSA oversees more than 70 deep-sea, rail, and inland terminals in over 40 countries, achieving a group throughput of 100.2 million TEUs in 2024, with international operations contributing 59.2 million TEUs.^[63]^[64]^[62] Advancements in automation and technology define PSA's efficiency gains, including early systems like PORTNET for electronic documentation and recent deployments of AI-driven digital twins, automated guided vehicles, and remote quay cranes at Tuas, which have cut vessel turnaround times to under 24 hours for mega-vessels and boosted throughput per berth. These investments, exceeding hundreds of millions in phased Tuas development, enable high crane productivity rates—often over 40 moves per hour—facilitating resilient supply chains amid volatile trade volumes.^[62]^[65] Notwithstanding these efficiencies, PSA's centrality in Asia-Pacific trade routes exposes it to geopolitical risks, such as disruptions from South China Sea tensions or U.S.-China decoupling, which could reroute volumes and strain transshipment dependencies; involvement in Belt and Road-linked ports raises concerns over long-term vulnerability to Chinese influence on infrastructure standards and financing, potentially amplifying supply chain fragilities in event of alliance shifts. Analyses note that while Singapore's neutral hub status mitigates some risks, over-reliance on regional chokepoints heightens exposure to non-market interventions or blockades, prompting diversification calls from trade observers.^[66]^[67]

Country-specific organizations

In Australia, the Public Service Association (PSA) of New South Wales functions as a trade union representing approximately 40,000 public sector employees across government departments, universities, and related entities, focusing on collective bargaining for wages, conditions, and workplace rights.^[68] Similar PSAs operate in other states, such as South Australia, where the organization advocates for public servants in administrative and operational roles, emphasizing dispute resolution and policy influence grounded in membership data on employment trends.^[69] In the United Kingdom, the Property Services Agency (PSA) operated from 1972 to 1993 as a non-ministerial government department responsible for procuring, managing, and maintaining the civil estate, including office buildings and infrastructure for public administration, with annual budgets exceeding £1 billion by the 1980s to support efficient asset utilization.^[70] It was dissolved in 1996 amid privatization efforts, transferring functions to agencies like the Crown Estate and private sector providers to reduce bureaucratic overhead.^[71] The Philippine Statistics Authority (PSA), established in 2013 under Republic Act No. 10625 by merging the National Statistics Office and other bodies, serves as the central government agency for collecting, processing, and disseminating statistical data on population, economy, and society, producing outputs like the Census of Population and Housing with verified accuracy rates above 95% through rigorous validation protocols. Its empirical focus includes generating indicators for GDP estimation and labor force surveys, prioritizing data integrity over interpretive expansions. In the United States, the Pretrial Services Agency (PSA) for the District of Columbia, created under the National Capital Revitalization and Self-Government Improvement Act of 1997, conducts investigations and supervises defendants released pending federal trials, using risk assessments based on criminal history and flight propensity data to recommend conditions that minimize recidivism, with supervision caseloads averaging over 10,000 annually.^[72] In Norway, the Petroleum Safety Authority (PSA), established in 2004 succeeding the Norwegian Petroleum Directorate's safety division, regulates health, safety, and environmental standards in offshore petroleum activities, enforcing compliance through audits and incident analyses that have contributed to a decline in serious injuries from 5.2 per million work hours in 2000 to under 1 by 2020.

Government and public sector

Personal services agreement

A personal services agreement (PSA) constitutes a binding contract under which an individual renders specialized labor or services to a client, distinct from traditional employment by eschewing direct supervision akin to an employer-employee dynamic. In U.S. federal procurement, PSAs leverage statutory exemptions, such as 22 U.S.C. § 2669(c), permitting agencies like the Department of State to engage personnel for roles resembling direct-hire positions without full civil service obligations.^[73] The Federal Acquisition Regulation (FAR) delineates personal services contracts—often overlapping with PSAs—as those fostering an employer-employee relationship through government control over methods, hours, and performance location, rendering them generally impermissible absent explicit authorization to circumvent anti-deficit hiring restrictions and benefit costs.^[74] This framework contrasts with independent contractor arrangements, where the service provider retains autonomy over execution, as evaluated via IRS behavioral, financial, and relational control tests.^[75] PSAs proliferate in consulting and government outsourcing to enhance operational flexibility, enabling rapid scaling without entrenched payroll commitments or benefits liabilities, thereby reducing fiscal burdens—federal agencies reported outsourcing services valued at over $300 billion annually as of fiscal year 2022, partly via such mechanisms.^[76] Proponents highlight market-driven efficiencies: skilled professionals command premium rates untethered from salary caps, fostering innovation through transient expertise. Empirical data on analogous independent contracting reveals net positives for high-skill sectors, with consultants averaging 20-30% higher hourly compensation than salaried equivalents after adjusting for self-employment taxes, though outcomes vary by industry.^[77] Conversely, critiques center on worker precarity, including absent unemployment insurance, workers' compensation, and health coverage, exacerbating vulnerability during economic downturns—studies document independent contractors facing 1.5 times the income instability of employees in service-oriented fields.^[78] Enforceability demands meticulous drafting to evade reclassification risks under common law agency principles or statutes like the Fair Labor Standards Act, where excessive client direction signals disguised employment, inviting back-pay claims and penalties. Courts enforce PSAs when terms delineate discrete deliverables, payment by milestone rather than time, and provider discretion, as affirmed in precedents distinguishing contractual services from personal labor bonds.^[79] Violations, such as FAR-proscribed personal services without waiver, can nullify agreements and trigger audits, underscoring the causal primacy of regulatory adherence over intent in sustaining validity. While debates persist on equity—labor advocacy sources decry systemic exploitation, yet econometric reviews affirm voluntary arrangements yield efficient resource allocation absent coercive barriers—PSAs remain viable for targeted, non-core functions where empirical wage premia offset forgone protections for autonomous actors.^[80]

Public sector agreement

Public sector agreements encompass collective bargaining arrangements between government employers and public sector trade unions, focusing on terms such as wages, pensions, and performance-linked incentives for employees in areas like education, healthcare, and civil service. These pacts aim to balance worker protections with fiscal constraints, often spanning multi-year periods to provide predictability amid political changes. In practice, they have been criticized for embedding rigid structures that prioritize job security over efficiency, contributing to elevated labor costs relative to output.^[81] In the United Kingdom, public sector pay and performance deals proliferated from the late 1990s through the 2000s, integrating union negotiations with government targets under frameworks like the 1998 Comprehensive Spending Review's Public Service Agreements, which tied funding to measurable outcomes while influencing compensation structures. These arrangements covered approximately 5.5 million public workers, emphasizing pensions and incremental pay rises contingent on productivity metrics. By the 2010s, fiscal pressures post-2008 crisis prompted reforms, including a 1% annual pay cap from 2013 to 2017 and shifts away from centralized bargaining, effectively dismantling many performance-linked pacts in favor of decentralized or restrained negotiations.^[82]^[83] Empirical analyses reveal mixed economic impacts, with public sector agreements linked to lower productivity growth compared to the private sector; UK public service productivity declined by an average of 0.3% annually from 1997 to 2019, partly attributed to inelastic pay structures resistant to cost controls. Adjusted for education and experience, public sector earnings showed a negligible premium of 0% for men and 4% for women between 2002 and 2016, though unadjusted figures often exceed private equivalents by 10-15%, imposing higher taxpayer burdens estimated at billions in forgone efficiency.^[84]^[85]^[86] Union advocates contend these agreements safeguard essential services from politicized cuts, ensuring recruitment in low-turnover roles, yet strikes underscore tensions with public costs; the 2011 pension reform disputes, involving 2.5 million workers across 29 unions, closed 19,000 schools and canceled 6,000 operations, generating £500 million in economic losses from disrupted services. Such actions highlight causal trade-offs: while providing leverage for concessions, they impose immediate fiscal and service delivery strains, with productivity lags persisting into the 2020s amid ongoing disputes.^[87]^[88]

Sports

Professional Skaters Association

The Professional Skaters Association (PSA) was a nonprofit organization established to advance the professional development of figure skating coaches through education, training, and accreditation programs. Founded on August 10, 1938, it operated as the official body for certifying coaches in the United States, offering ratings based on experience, seminars, and evaluations to ensure competency in teaching techniques from beginner to elite levels.^[89]^[90] By its later years, PSA had accredited thousands of professionals, influencing standards adopted by U.S. Figure Skating (USFS) in areas such as instructional methodology and ethical practices.^[91] At its peak, PSA maintained a membership of approximately 6,400 coaches worldwide, including those training athletes at rinks, clubs, and competitive programs, along with associate members such as judges and skating enthusiasts.^[90] The organization provided ongoing seminars and workshops on topics including injury prevention, concussion protocols, and off-ice conditioning, contributing to enhanced safety and training efficacy in figure skating.^[92] These efforts helped standardize coach qualifications, reducing variability in instruction and supporting athlete progression toward national and international competition.^[93] In 2023, USFS integrated PSA's accreditation framework, granting equivalent status to former PSA-rated coaches upon completion of updated core certification and background requirements, effectively merging PSA's educational legacy into the national governing body's structure.^[91] This transition preserved PSA's contributions while aligning them with USFS's broader SafeSport initiatives and membership pathways, which emphasize misconduct prevention and professional accountability.^[94] Prior to dissolution, PSA faced regulatory scrutiny in 1999 when the Federal Trade Commission challenged its code of ethics for restricting coaches from soliciting clients from member rinks, leading to modifications to promote competitive fairness.^[95]

Other uses

Pressure swing adsorption

Pressure swing adsorption (PSA) is a cyclic gas separation process that exploits differences in the adsorption affinities of gas components onto a solid adsorbent material, typically under varying pressure conditions. In the adsorption step, a gas mixture is pressurized and passed through adsorbent beds (e.g., zeolites or activated carbon), where preferentially adsorbed impurities such as water vapor, CO₂, or oxygen are captured, allowing the desired gas (e.g., nitrogen or hydrogen) to pass through as a purified stream. The adsorbent is then regenerated by depressurization, purging with a portion of the purified gas or vacuum assistance, releasing the adsorbed components for venting or recovery. This non-cryogenic method operates at ambient temperatures, distinguishing it from distillation-based alternatives.^[96]^[97] The foundational Skarstrom cycle, patented in 1960, enabled the basic two-bed PSA configuration for oxygen enrichment from air, marking the onset of practical implementation. Commercial adoption accelerated in the mid-1960s, with the first hydrogen purification PSA unit installed in 1966 alongside a steam methane reformer in Toronto, utilizing four adsorber beds to achieve high-purity H₂ recovery from syngas mixtures containing CO, CO₂, and CH₄. By the early 1970s, PSA scaled to industrial oxygen production from air, supplanting some cryogenic systems in niche applications due to modular design and lower startup costs. Ongoing refinements, including multi-bed polybed configurations and vacuum-assisted variants (VPSA), have expanded its versatility for trace impurity removal and bulk separations.^[98]^[99]^[100] PSA finds primary applications in nitrogen generation from air for inerting (up to 99.999% purity via zeolite adsorbents targeting O₂), hydrogen recovery from refinery or reforming off-gases (recovering >90% H₂ at 99.99% purity), and emerging biogas upgrading to biomethane by selective CO₂ removal (achieving >95% CH₄ purity). In hydrogen purification, PSA processes recover over 85-90% of H₂ from streams post-water-gas shift, critical for fuel cell feeds or ammonia synthesis, though debates in hydrogen economy contexts highlight its energy efficiency (0.1-0.3 kWh/Nm³ H₂ purified) relative to electrolysis, which avoids separation but incurs higher upstream generation costs for non-electrolytic routes like steam reforming. Recent advancements in biogas PSA, reviewed in 2024, emphasize dual-bed or multi-step cycles with 95-98% methane recovery at low operating pressures (4-8 bar), positioning it as a cost-effective alternative to membrane or amine scrubbing for decentralized renewable gas purification.^[101]^[102]^[103] Compared to cryogenic distillation, PSA offers lower specific energy consumption (e.g., 0.2-0.4 kWh/Nm³ for N₂ vs. 0.5-1.0 kWh/Nm³ cryogenic) and capital expenditure for capacities under 100 tons/day, avoiding refrigeration cycles and enabling rapid startup/shutdown. However, limitations include reduced efficiency at ultra-large scales (>500 tons/day) due to mass transfer constraints in packed beds, higher compression energy for low-pressure feeds, and adsorbent degradation from contaminants like sulfur compounds. Scale-up challenges manifest as increased pressure drops and reduced throughput per bed volume, often necessitating hybrid systems for gigawatt-scale hydrogen plants.^[104]^[105]^[106]

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Aug 6, 2014 · The European Randomised study of Screening for Prostate Cancer (ERSPC) has shown significant reductions in prostate cancer mortality after 9 ...
[17]
The High Prevalence of Undiagnosed Prostate Cancer at Autopsy
Autopsy studies confirm a high prevalence of asymptomatic and undiagnosed prostate cancers in men as young as 30 years of age, and the prevalence increases with ...
[18]
Overdiagnosis and Overtreatment of Prostate Cancer - ScienceDirect
Epidemiological, clinical, and autopsy studies have been used to examine PCa overdiagnosis, with estimates ranging widely from 1.7% to 67%.
[19]
Styrene-Acrylonitrile Copolymer - an overview | ScienceDirect Topics
SAN, or styrene-acrylonitrile copolymer, is defined as a solid polymer composed of approximately 25-30% acrylonitrile and 70-75% styrene, with a weight ...Missing: history | Show results with:history
[20]
SAN/AS Plastic: Properties, Applications, and Processing - Team MFG
Typically, SAN consists of 70-80% styrene and 20-30% acrylonitrile. This ratio is crucial, as it determines the balance of properties in the final product.Missing: history | Show results with:history<|separator|>
[21]
Process for the manufacture of styrene-acrylonitrile copolymers
SAN copolymers are conventionally manufactured by suspension copolymerization in the following way: The reactor is initially charged with all the water and ...Missing: properties history
[22]
Styrene Acrylonitrile Resin - SAN Polymer Uses & Properties
Apr 27, 2024 · Thermal Conductivity, 0.113 – 0.195 W/m-K ; Glass Transition Temp, Tg, 102 – 104 °C ; Flammability, UL94, HB – 5VA ; Oxygen Index, 18.0 – 19.5 %.
[23]
Glass Transition Temperature (Tg) of Plastics - Definition & Values
Aug 12, 2025 · The test standards used to determine Glass Transition Temperature of resins via DTA include: ... SAN - Styrene Acrylonitrile, 100.0, 115.0. SAN, ...
[24]
Acrylonitrile Butadiene Styrene (ABS) and Other Specialist Styrenics
Styrene Acrylonitrile copolymers have been available since the 1940's and while its increased toughness over styrene made it suitable for many applications, ...
[25]
SAN Resins, Their Uses, and Advantages Discussed in Detail
Oct 22, 2020 · SAN polymers is one of the oldest styrene polymers used today. It has been used since the 1940s, and is preferred over polystyrene owing to its ...Missing: development history 1950s<|control11|><|separator|>
[26]
A Word About Public Service Announcements - PSA Research Center
Apr 15, 2022 · Public service announcements are a vital tool in generating awareness for critical issues while dispensing important information for many non-profit ...
[27]
[PDF] Fairness Doctrine - Federal Communications Commission
With respect to the fairness doctrine itself, a policy that the Commission defended before the Supreme. Court in 1969, our comprehensive study of the telecom-.
[28]
The History and Possible Revival of the Fairness Doctrine - Imprimis
The Fairness Doctrine itself was in effect from 1949 until 1987. It required that radio broadcasts devote a reasonable amount of time to the discussion of ...
[29]
Tips Impact and Results | About the Campaign - CDC
Higher levels of exposure to the Tips campaign were associated with lower odds of relapse to cigarette smoking. During 2012–2018, CDC's Tips From Former ...Missing: data youth
[30]
Variations in State Use of Anti-Tobacco Message Themes Predict ...
A 100-ad increase in the yearly volume of youth-targeted state anti-smoking PSAs was associated with a 0.1 percentage point decrease in state youth smoking ...
[31]
Project D.A.R.E. Outcome Effectiveness Revisited - PMC
We provide an updated meta-analysis on the effectiveness of Project DARE in preventing alcohol, tobacco, and illicit drug use among school-aged youths.
[32]
The effectiveness of anti-illicit-drug public-service announcements
A meta-analysis of eligible randomised trials demonstrated no significant effect. Observational studies showed evidence of both harmful and beneficial effects.
[33]
The route to improve the effectiveness of negative PSAs
In fact, a meta-analysis showed that negative PSAs are, on average, less effective than positive ones in terms of message acceptance (O'Keefe & Jensen, 2008).
[34]
Controversial Super Bowl PSA suggests new directions in corporate ...
Jan 30, 2020 · The controversial PSA focuses on the death of Botham Jean, an unarmed black man who was shot to death in his apartment by a Dallas police ...
[35]
'Hypocritical Much?' Critics Blast NFL's PSA Highlighting 'Human ...
Jan 23, 2020 · A public service announcement honoring the life of Botham Jean and showing the "human cost of police brutality" will be shown during the ...
[36]
[PDF] The ARPANET IMP (Interface Message Processor) Port Expander
Up to five 1822 distant-host interface bulkhead connectors of the standard type (Amphenol 1S24260R18831SN). One connector is for the IMP, and the remainder for ...
[37]
[PDF] The ARPANET and the DARPA Internet - Sign-in
as new host interface standards have been adopted. Several of the ARPANET interfaces have been desig- nated as 1822 interfaces, referring to the number of ...
[38]
ARPANET - Computer History Wiki
Oct 6, 2025 · (The 1822 'Local Host' and 'Distant Host' interface variants had maximum lengths of about 100 feet and 2,000 feet respectively; to allow ...
[39]
RFC 878: ARPANET 1822L Host Access Protocol
The 1822 NOPs will contain the 1822 address of the host interface, and the 1822L NOPs will contain the corresponding 1822L address. Once the IMP and the ...
[40]
RFC 851 - ARPANET 1822L Host Access Protocol - IETF Datatracker
Mar 2, 2013 · The 1822 NOPs will contain the 1822 address of the host interface, and the 1822L NOPs will contain the corresponding 1822L address. Once the ...<|separator|>
[41]
Interface Message Processor - Computer History Wiki
Oct 6, 2025 · The Interface Message Processor (or IMP, as they were universally known) was the packet ... host interface hardware. ARPANET Technical Information ...
[42]
PSA Groupe - autolexicon.net
In 1976, the joint-stock company Peugeot Société Anonyme (PSA) was formed, which took over 89.95% of the shares of the then-bankrupt Citroën company. Today, PSA ...Missing: founded | Show results with:founded
[43]
History of the PEUGEOT Family
In 1976, it became PSA PEUGEOT Citroën through the merger of Citroën S.A. and PEUGEOT S.A.. PSA Peugeot Citroën then became the PSA Group in 2016 and today ...Missing: Groupe | Show results with:Groupe
[44]
Groupe PSA future model plans - Peugeot - Just Auto
Jun 12, 2019 · The second generation 3008, one of the best sellers in the European market's C-crossover/SUV segment, is coming up for three years old.Missing: Group | Show results with:Group
[45]
Peugeot Citroen says third-party tests confirm BlueHDi SCR tech for ...
Jan 18, 2016 · There are three primary elements to the BlueHDi system includng an oxidation catalyst, SCR technology, and a diesel particulate filter. The ...
[46]
PEUGEOT rolls out its BlueHDi technology to the Boxer
They are based on the latest generation of 2-litre DW Diesel engines from the PSA Group, incorporating the Euro 6 BlueHDi technology that has already been sold ...
[47]
PSA Group 2019 sales slump 10% after record 2018 | Reuters
Jan 15, 2020 · French carmaker PSA Group <PEUP.PA> said on Thursday global sales fell 10% last year to 3.49 million units, compared with a record 3.88 ...
[48]
French group PSA recalls 97,000 cars - Drive
Feb 1, 2010 · The French automobile group PSA says it will recall 97,000 Peugeot 107s and Citroen C1s made in a Czech factory it shares with Japanese ...
[49]
After Toyota, Peugeot Citroën to recall cars made in Czech plant
Jan 30, 2010 · The French auto group PSA Peugeot Citroën announced the recall of cars built in a Czech plant shared with Toyota after the giant Japanese ...Missing: Groupe | Show results with:Groupe
[50]
[PDF] Regulation and Competitiveness of the EU Automotive Industry ...
With regulatory costs progressively increasing, continued disproportionate regulatory burden will exacerbate the problem. Background. 4.2. At its peak in 2007, ...
[51]
Securing Europe's automotive competitiveness for jobs and value ...
Sep 26, 2025 · Competitive electricity prices, lower regulatory burdens, and policies to secure EU know-how and local content are vital to attract ...
[52]
The merger of FCA and Groupe PSA has been completed | Stellantis
Jan 16, 2021 · January 16, 2021. The merger of FCA and Groupe PSA has been completed. London - The merger between Peugeot S.A. (“Groupe PSA”) and Fiat ...
[53]
Stellantis Sees Improved Profitability in 2021 After Merger - Bloomberg
Mar 3, 2021 · Stellantis Sees Improved Profitability in 2021 After Merger. Carmaker expects margin between 5.5% to 7.5% this year; Fiat and PSA exceeded ...<|separator|>
[54]
EU losing ground in global automotive market, new study reveals
Sep 10, 2025 · Europe's automotive suppliers are issuing a stark warning based on a recent study of European value creation.
[55]
Who We AreAbout PSA Airlines
Who We AreAbout PSA Airlines. PSA is a proud wholly owned subsidiary of American Airlines Group. We are focused on creating opportunities for our people and our ...Life at PSA · View Culture · Our FleetMissing: founding | Show results with:founding<|separator|>
[56]
PSA Airlines: Home
PSA Airlines announced the relocation of its headquarters from Dayton, Ohio to Charlotte. The new headquarters is expected to open in January 2026 and will ...Who We Are · Contact Us · Route Map · PSA Airlines relocating its...
[57]
PSA Airlines Fleet Details and History - Planespotters.net
Country, United States ; Founded, 1979 ; Started Operations, 1 Nov 1995 ; Predecessor. Jetstream International Airlines (OH / JIA).
[58]
American Airlines Group − Customer service
Three are wholly owned subsidiaries of American Airlines Group: Envoy Air Inc. Piedmont Airlines Inc. PSA Airlines Inc. As well as 2 other contracted ...
[59]
Fleet | PSA Airlines
We proudly operate an all-jet fleet consisting of exclusively MHI RJ regional aircraft including the CRJ700 and CRJ900.
[60]
Route Map - PSA Airlines
... operating more than 600 daily flights to nearly 100 destinations on behalf of American Airlines. Headquartered in Dayton, Ohio, PSA also has flight crew ...
[61]
Our Story - PSA Singapore
In the 1970s, PSA started a container port and handled their first container ship. In the following decades, PSA grew and reached the 5-million TEU mark by 1990 ...Missing: establishment privatization
[62]
PSA International (PSA) is a leading global port operator and trusted ...
Aug 8, 2025 · By 1990, PSA Singapore was the world's largest container port, handling five million TEUs annually. Our international journey began in 1996 in ...Missing: history privatization
[63]
Terminals | Maritime & Port Authority of Singapore (MPA)
PSA Corporation Limited operates five container terminals at Tanjong Pagar, Keppel, Brani, Pasir Panjang and Tuas as one seamless and integrated facility.
[64]
PSA International's 2024 Container Throughput Performance
Jan 16, 2025 · PSA achieved 100.2 million TEUs in 2024, with 40.9 million in Singapore and 59.2 million outside, a 5.6% increase overall.
[65]
PSA increasing container throughput utilizing latest automation ...
Mar 5, 2025 · Container terminal operator PSA International is using automated technology to make throughput and transshipment more efficient.Missing: investments turnaround
[66]
In the eye of a geopolitical storm: responses of port management ...
Oct 1, 2025 · The biggest potential investment risks concern dependency risks and disruption risks in the area of port and maritime operations and ...<|control11|><|separator|>
[67]
One Belt, One Road: Opportunities and Risks for Singapore (Part 1)
Oct 2, 2017 · This is part 1 of a two-part blog post on the One Belt, One Road or Belt and Road Initiative and the opportunities and risk this poses for Singapore as a ...
[68]
Public Service Association
The Public Service Association of New South Wales and Community and Public Sector Union (SPSF Group) NSW Branch acknowledges the Traditional Custodians.ContactLatest NewsMembers' AreaJoining the PSAMember Benefits
[69]
Public Service Association of SA
Join the PSA today. The Public Service Association of SA Inc is the principal union representing public sector workers in South Australia.
[70]
[PDF] The Property Services Agency - The Centre for Policy Studies
The origins of the Property Services Agency can fairly be traced back to the Middle Ages when the Sovereign employed a Clerk of the Works to maintain the ...
[71]
Property Services Agency – Management of the Civil Estate - NAO ...
Property Services Agency – Management of the Civil Estate · On this page · Downloads · Publication details · Latest reports · Subscribe for updates.<|separator|>
[72]
Pretrial Services Agency: Home
The Pretrial Services Agency for the District of Columbia (PSA) is the federal agency responsible for gathering information about newly arrested defendants and ...
[73]
637.104-71 Personal services agreements. - Acquisition.GOV
Sep 24, 2019 · “Personal Services Agreement (PSA)” is a method of employment using the statutory authority under 22 USC 2669(c).
[74]
37.104 Personal services contracts. - Acquisition.GOV
(a) A personal services contract is characterized by the employer-employee relationship it creates between the Government and the contractor's personnel.
[75]
Independent contractor (self-employed) or employee? - IRS
Aug 7, 2025 · Learn how to determine whether a person providing a service to you is an employee or an independent contractor.
[76]
Part 37 - Service Contracting - Acquisition.GOV
(a) A personal services contract is characterized by the employer-employee relationship it creates between the Government and the contractor's personnel. The ...
[77]
Being a Consultant, Freelancer, or Contractor: Pros and Cons - Nolo
No Job Security · No Employer-Provided Benefits · No Unemployment Insurance Benefits · No Employer-Provided Workers' Compensation · Few or No Labor Law Protections.
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Independent Contracting in California: An Analysis of Trends and ...
Mar 1, 2022 · Independent contractors with low earnings were more likely to work in industries such as personal services, janitorial services, and landscaping ...
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Fact Sheet 13: Employment Relationship Under the Fair Labor ...
If the economic realities show that the worker is in business for themself, then the worker is an independent contractor. The economic realities of the entire ...Missing: personal | Show results with:personal<|separator|>
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[PDF] What Do We Know About Alternative Work Arrangements in the ...
Jan 5, 2022 · Our literature review and empirical analyses are designed to provide further insights into the incidence and trends in alternative work ...Missing: agreements | Show results with:agreements
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Recent trends in public sector pay | Institute for Fiscal Studies - IFS
Mar 26, 2024 · Overall, between December 2019 and November 2023, inflation-adjusted average private sector pay grew by 2.3%, whereas public sector pay fell by 0.3%.
[82]
[PDF] Public Service Agreements - UK Parliament
Dec 7, 2005 · Public Service Agreements (PSAs) were first introduced in the 1998 Comprehensive. Spending Review which set around 600 performance targets ...Missing: 1990s | Show results with:1990s
[83]
[PDF] Public Sector Pay - UK Parliament
Feb 26, 2025 · Public sector employees will receive a pay increase of up to 6% in 2024/25. For 45% of the sector, pay is based on Pay Review Body ...
[84]
The fiscal implications of public service productivity - IFS
May 30, 2024 · Because real funding grew faster than outputs (2.6% versus 2.3%), our measure of funding productivity fell by an average of 0.3% per year.
[85]
The public–private sector wage differential in the UK
The estimated average public sector premium received by men between 2002 and 2016 men was zero. The value among women was 4%.Missing: comparison studies<|control11|><|separator|>
[86]
[PDF] Does it pay to be a public-sector employee? | IZA World of Labor
Public-sector employees earn about 15% more, but the long-term pay gap is negligible in many countries, and the lifetime career value is close to zero in some.
[87]
Strikes over public sector pensions hit services across UK as 2 ...
Nov 30, 2011 · The impact includes: 19,000 out of 21,700 schools in England and Wales closed or partially closed. 6,000 out of 30,000 non-urgent operations ...
[88]
Public sector strikes disrupt services across England - BBC News
Nov 30, 2011 · Public sector workers strike over pension changes in a day of action which closed thousands of schools and disrupted services.
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Professional Skaters Foundation: Professional Skating Foundation
Founded in 1938, The Professional Skaters Association International was dedicated to providing continuing education and accreditation to ice skating ...
[90]
Professional Skaters Association Company Profile - Datanyze
The Professional Skaters Association (PSA) was organized in 1938. The PSA is the official figure skating coach's education, training and accreditation program ...
[91]
Coach | U.S. Figure Skating
The Core course provides fundamentals needed to become a coach. After completing the Core Certification Course, coaches are eligible to join U.S. Figure Skating ...
[92]
Case in Point: Skating Into Sports Medicine in
Apr 5, 2023 · Furthermore, the Professional Skaters Association offers coaches seminars about concussions and off-ice workouts that athletes should be ...
[93]
PSA Legacy - Professional Skaters Foundation
For 86 years, The Professional Skaters Association International provided continuing education and accreditation to ice skating professionals in a safe and ...
[94]
SkateSafe® | U.S. Figure Skating
US Figure Skating strives to provide a safe environment for its members that is free of misconduct and harassment.
[95]
Professional Skaters Association, Inc., In the Matter of
The FTC charged that the Professional Skaters Association, through its code of ethics, broadly bans members from soliciting other members' students.
[96]
Theory and application of pressure swing adsorption for the ...
The three PSA processes include single component solvent vapor recovery, single component air purification with complete clean-up, and binary solvent vapor ...
[97]
Precombustion CO2 Capture by Pressure Swing Adsorption (PSA)
Jun 7, 2013 · Pressure swing adsorption (PSA) experiments are carried out in a 2-column laboratory setup using activated carbon. As feed an equimolar CO 2 /H 2 mixture is ...<|separator|>
[98]
Review of Polybed pressure swing adsorption for hydrogen ...
PSA for hydrogen purification. Since the invention of the Skarstrom cycle in 1960, PSA has rapidly evolved into one of the most efficient gas separation ...
[99]
[PDF] Review of Polybed pressure swing adsorption for hydrogen ...
The first commercial H2 PSA unit was installed in 1966 in conjunction with a steam reformer plant in Toronto and was composed of four adsorbers and a tail gas ...
[100]
The Production of Industrial‐Grade Oxygen from Air by Pressure ...
Jan 19, 2023 · The first PSA was used for air fractionation in the 1960s, while the early 1970s marked the commercial use of PSA for oxygen production [10, 11] ...
[101]
An overview of biogas upgrading via pressure swing adsorption
Apr 15, 2024 · The first PSA system could be traced back to 1960; when Charles Skarstrom patented the process for oxygen enrichment and called it Skarstrom's ...
[102]
Biogas Upgrading by Pressure Swing Adsorption - IntechOpen
The initial work reporting Pressure Swing Adsorption technology was signed by Charles W. Skarstrom in 1960 (Skarstrom, 1960). A similar cycle was developed by ...<|separator|>
[103]
Green Hydrogen Recovery from Natural Gas Grids by Vacuum ...
This study focuses on the development of a conceptual vacuum pressure swing adsorption process (VPSA) for green hydrogen (GH) recovery from natural gas ...
[104]
Cryogenic Air Separation vs PSA: Which Technology Fits Your Gas
May 16, 2025 · Cryogenic separation uses cooling for high purity, while PSA uses adsorption under pressure. Cryogenic is for large-scale, high purity; PSA is ...Overview of the Two... · II. Comparison Criteria · IV. Hybrid Solutions and...
[105]
Pressure Swing Adsorption (PSA): The Efficient Gas Separation ...
Jun 19, 2025 · PSA vs. Cryogenic Distillation. PSA has advantages over cryogenic distillation because it works at room temperature. This saves a lot of energy.
[106]
Adsorbent shaping as enabler for intensified pressure swing ...
Jan 19, 2025 · However, there are some challenges to overcome such as mass transfer limitations leading to reduced separation efficiency, as well as increased ...