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LOC

The (LOC) is the primary research institution serving the , functioning as the de facto national library of the country and the oldest federal cultural institution in the United States. Established on April 24, 1800, through legislation signed by President allocating funds for a congressional reference collection initially housed in the U.S. Capitol, it has grown into the world's largest library by volume of materials held. As of 2025, its collections exceed 181 million items, encompassing books, manuscripts, photographs, maps, films, audio recordings, and digital media in hundreds of languages, acquired daily through deposits, purchases, and donations. The LOC administers the U.S. Copyright Office, registers copyrights under federal law, and supports legislative analysis via the nonpartisan , which prepares reports and briefings grounded in primary sources and data. Its facilities, including the , , and on in , alongside extensive off-site storage, preserve irreplaceable cultural and historical artifacts while providing public access through reading rooms, digital archives, and exhibitions. Notable for rebuilding after British forces destroyed much of its early collection during the —replenished by President Thomas Jefferson's donation of over 6,000 volumes—the institution emphasizes preservation of primary records over interpretive narratives, serving scholars, lawmakers, and the public with tools for empirical inquiry.

Institutions and Organizations

Library of Congress

The , established on April 24, 1800, when President signed an act appropriating $5,000 to purchase books for the use of Congress as the U.S. capital relocated to , serves as the nation's oldest federal cultural institution and research library. Initially housed in the , its collections were largely destroyed by British forces during the on August 24, 1814, prompting a rebuilding effort bolstered by President Thomas Jefferson's donation of over 6,000 volumes from his personal library in 1815, which expanded its scope beyond legislative materials to include broader scholarly works. Today, it holds the world's largest collection of books and recorded knowledge, encompassing more than 175 million items across 470 languages, including printed materials, manuscripts, photographs, maps, films, and sound recordings. As the primary research arm of the U.S. Congress, the Library provides nonpartisan analysis and reports through the Congressional Research Service to support legislative decision-making based on empirical data and historical precedents. It also administers the U.S. Copyright Office, which registers creative works and serves as a repository for copyright deposits, thereby preserving millions of deposited items that contribute to its archival holdings while facilitating public access under legal frameworks. These functions underscore its dual role as a legislative resource and de facto national library, prioritizing the accumulation and safeguarding of primary sources over interpretive narratives. The Library's preservation efforts, managed by its Preservation Directorate, focus on conserving physical and digital collections to ensure long-term accessibility, countering degradation from environmental factors, use, and time through techniques like reformatting and climate-controlled storage. Digital initiatives, such as the launched in 2009 in partnership with , digitize and provide free global access to culturally significant primary documents from partner institutions, enabling direct examination of originals to verify claims against potentially biased secondary accounts prevalent in academic and media sources. This emphasis on unaltered artifacts supports of historical events by making verifiable evidence available, mitigating distortions from institutional interpretive biases.

Geopolitical and Military Terms

Line of Control

The (LoC) is a 740-kilometer that separates Indian-administered from Pakistani-administered areas of the disputed region, established as a line following the 1947-1948 Indo-Pakistani War and formalized in 1972. It runs from the Chamb sector near the with in the north to the international border between and in the south, dividing the former into two administrative zones without constituting a permanent international boundary. The of July 2, 1972, signed after Pakistan's defeat in the 1971 war, renamed the 1949 line as the LoC and committed both nations to bilateral negotiations for resolution, eschewing third-party intervention like UN mediation. The LoC's origins trace to the 1947 partition of British , when Jammu and 's Hindu ruler, Maharaja Hari Singh, delayed accession amid communal violence; on October 22, 1947, Pashtun tribal militias backed by Pakistani regulars invaded to seize the Muslim-majority territory, prompting the Maharaja's accession to on and . This sparked the first Indo-Pakistani War, ending in a UN-brokered on , 1949, along a line that violated by sponsoring irregular incursions rather than withdrawing forces as stipulated in UN Security Council Resolution 47, which envisioned a plebiscite contingent on demilitarization—conditions unmet due to 's non-compliance. maintains the LoC respects the Maharaja's legal accession and integrates the region fully, as reinforced by the August 5, 2019, revocation of Article 370, which ended special autonomy and reorganized into union territories to assert central governance over what deems an internal matter. , administering "Azad" and , rejects the accession as coerced and views the LoC as temporary, advocating plebiscite under UN auspices to enable , while supporting Kashmiri separatists through proxy groups like . Conflicts along the LoC stem asymmetrically from Pakistan-initiated crossings and artillery fire to facilitate militant infiltration, as evidenced by the 1999 Kargil intrusion where Pakistani Infantry and militants occupied Indian heights, leading to India's that recaptured positions by July 26 at a cost of 527 Indian fatalities. Similarly, the February 14, 2019, Pulwama suicide bombing by JeM—killing 40 Indian paramilitary—prompted India's February 26 on a JeM camp in , , targeting terrorist infrastructure beyond the LoC. Ceasefire violations, predominantly initiated by to aid cross-border , peaked at over 3,000 annually pre-2021 but dropped sharply after a February 25, 2021, understanding, with official data recording only six from February to June 2021 versus hundreds prior. This pattern underscores causal drivers: 's state tolerance of jihadist networks perpetuates instability, contrasting India's defensive posture and fencing efforts along 550 km of the LoC to curb infiltration.

Technology and Computing

Lines of Code

Lines of Code (LOC), also termed source lines of code (SLOC), quantifies software size by counting non-blank, non-comment lines containing executable statements, such as declarations and control structures. This metric originated in the late 1960s and gained prominence in the 1970s for estimating developer productivity, with benchmarks like 50 lines per day for assembly-like languages using era-specific tools. Productivity assessments often normalized outputs to thousands of lines (KLOC), serving as a proxy for effort in cost models, though alternatives like function points—introduced by IBM's Allan Albrecht in the late 1970s—emerged to better capture delivered functionality independent of implementation details. Despite its simplicity, LOC correlates weakly with true software value, as multiple implementations of identical functionality vary widely in line count due to language choice, coding style, or redundancy; for example, high-level languages enable concise expressions that outperform verbose low-level equivalents in productivity without proportional LOC increases. Empirical evidence shows LOC incentivizes bloat, where legacy systems accumulate unnecessary lines, diminishing maintainability while metrics like —calculating linearly independent paths via edges minus nodes plus components—better predict defect density and refactoring needs. A stable linear relationship exists between LOC and , with LOC explaining up to 90% of variance, yet the latter prioritizes causal factors like branching over sheer volume for . In AI-driven development, LOC further understates efficiency, as large language models leverage post-2020 scaling laws—where capability emerges from exponential compute and data increases rather than code expansion—to generate or optimize programs, yielding functional equivalence with reduced human-authored lines; datasets like IBM's CodeNet, comprising 500 million lines across languages, train such models to compress complex tasks into minimal code. This dynamic exposes LOC's inadequacy for modern paradigms, where algorithmic leverage from trained weights supplants traditional volume-based proxies, often at the expense of overlooked trade-offs like verification overhead in secure or safety-critical systems. Prioritizing LOC can thus distort evaluations, favoring superficial output over robust, empirically validated measures of and reliability.

Aviation and Navigation

Localizer

The localizer (LOC) is a ground-based precision navigation aid integral to the (ILS), delivering lateral () guidance to during the final approach segment for runway alignment. Positioned 750 to 1,000 feet beyond the runway's departure end, its transmits directional signals that enable pilots to maintain the extended runway centerline with high accuracy, typically supporting approach sensitivities equivalent to 350 feet wide at the . The system operates in the VHF spectrum from 108 to 112 MHz, broadcasting two fan-shaped overlapping beams: one amplitude-modulated at 90 Hz (indicating left deviation) and the other at 150 Hz (right deviation). Aircraft receivers measure the difference in depth of (DDM) between these tones to generate a (CDI); equal modulation occurs on the precise course line, with full-scale CDI deflection representing about 2.5 degrees or 630 microamperes DDM. This configuration provides reliable horizontal guidance up to 18 nautical miles, independent of the glideslope for vertical path. Originating from early radio beam experiments in the 1929-1941 period under the Civil Aeronautics Authority, localizers achieved operational status in the 1940s as FAA-certified components for Category I-III approaches, defined by decreasing decision heights (from 200 feet to zero) and (RVR) minima down to 600 feet or less. These standards ensure signal integrity through specified coverage volumes and false course mitigation. Empirically, localizer precision facilitates all-weather landings by minimizing lateral misalignment in (IMC), where excursions from veer-offs constitute over 70% of departures per industry analyses; ILS-equipped s correlate with lower excursion rates in low-visibility events versus non-precision alternatives. Post-2000s regulatory shifts incorporating GPS/WAAS for backup have preserved localizer primacy in critical operations, as satellite signals lack equivalent ground-verified causal robustness against or spoofing. Drawbacks include vulnerability to multipath from nearby obstacles reflecting signals, which can distort the course up to 1-2 degrees, demanding empirical siting validations over theoretical models.

Medicine and Physiology

Level of Consciousness

In clinical and , level of consciousness (LOC) quantifies a patient's alertness and responsiveness to external stimuli, serving as a proxy for function integrity following injury or illness. The primary standardized tool is the (GCS), developed in 1974 by Graham Teasdale and Bryan Jennett at the to improve communication about impaired in head-injured patients. The GCS evaluates three components—eye-opening (1-4 points), verbal response (1-5 points), and motor response (1-6 points)—yielding a total score from 3 (deep unconsciousness) to 15 (fully alert); scores of 13-15 indicate mild impairment, 9-12 moderate, and ≤8 severe, often defining . This scale enables rapid, bedside in trauma settings, with empirical data showing inverse correlations between initial GCS and outcomes in (TBI), such as higher mortality (up to 80% for GCS 3-5) and poorer functional recovery. GCS facilitates prognostic stratification in acute care, where lower scores at admission predict extended intensive care needs and reduced survival in TBI cohorts; for instance, patients with GCS ≤8 require immediate interventions like intracranial pressure monitoring, supported by large-scale studies linking scores to 6-month mortality rates exceeding 50%. Its simplicity supports widespread use in prehospital and emergency contexts, outperforming subjective descriptors in inter-rater reliability for motor and eye responses, though verbal scoring shows more variability. Despite these strengths, GCS relies on observable behaviors rather than direct neural metrics, potentially overlooking causal disruptions like subcortical lesions evident on imaging, which better inform pathophysiology. Limitations include susceptibility to confounding factors, such as intubation nullifying verbal scores or cultural/ barriers depressing verbal components in non-native speakers, leading to artifactually low totals unrelated to core neurological . Empirical critiques highlight inter-observer inconsistencies (up to 20% disagreement in verbal/motor subscales) and failure to differentiate effects from intrinsic , prompting advocacy for adjunctive measures like quantitative EEG (qEEG), which analyzes power and to classify LOC with higher in sedated or aphasic patients, correlating strongly with GCS yet revealing dynamic brain states invisible to behavioral scales. Prioritizing EEG or multimodal imaging over GCS alone enhances for , as behavioral proxies alone risk misattributing outcomes to surface responses rather than verifiable electrophysiological disruptions.

Loss of Consciousness

Loss of consciousness (LOC) refers to a state in which an individual exhibits a temporary inability to respond to external stimuli due to cerebral hypoperfusion or other disruptions in brain function. In clinical contexts, brief LOC lasting less than 30 minutes, often termed syncope or fainting, is distinguished from prolonged episodes exceeding this duration, such as those associated with or , where recovery may not be spontaneous. Syncope typically involves rapid onset, postural collapse, and quick spontaneous recovery, whereas prolonged LOC signals potential structural brain injury requiring urgent intervention. Primary physiological causes of LOC include from reduced oxygen delivery to the brain, often via cardiac arrhythmias or ; traumatic impacts leading to ; and neurological events like seizures that disrupt normal cortical activity. Other contributors encompass metabolic disturbances, such as or , and vascular events like transient ischemic attacks, each interrupting the brain's arousal mechanisms rooted in and thalamic pathways. Empirical data underscore that even transient episodes carry risks if recurrent, as fails to compensate adequately under repeated stress. Post-2020 neuroimaging studies have established causal links between repeated sports-related head impacts inducing LOC and early neurodegenerative changes, including neuronal loss and , preceding full (CTE) pathology. For instance, a 2025 NIH-funded of young athletes exposed to sports revealed tau protein accumulation and microglial activation from subconcussive blows, challenging prior underestimations of cumulative effects in athletic cohorts. Similarly, CTE Center research on former players documented that multiple LOC events correlate with 30-50% higher odds of , independent of diagnosed concussions, highlighting biomechanical forces as direct precipitants rather than mere correlations. These findings counter narratives minimizing long-term sequelae in high-impact sports, as autopsy-confirmed CTE in over 300 former NFL athletes post-2020 demonstrates progressive amyloid deposition tied to impact frequency. Evidence-based recovery protocols prioritize immediate stabilization to restore cerebral , such as positioning the patient with leg elevation for syncope to counteract , alongside and supplemental oxygen if hypoxic. For trauma-induced LOC, protocols mandate immobilization to prevent secondary injury, followed by imaging within 30 minutes to rule out hemorrhage, per guidelines. In cases of repeated episodes, such as in athletes, mandatory rest periods of 7-10 days minimum, with graded neurocognitive testing before return-to-play, reduce re-injury rates by up to 60% based on prospective cohort data. While immediate averts acute mortality—saving an estimated 20-30% of cardiac-syncope cases—critics note potential over-medicalization for isolated vasovagal events, advocating causal over blanket interventions to avoid iatrogenic harm. Long-term monitoring, including ambulatory EEG for differentiation, ensures causality-driven follow-up without assuming benign transience.

Finance and Business

Line of Credit

A line of credit (LOC) functions as a revolving borrowing arrangement extended by banks or , enabling borrowers—individuals, businesses, or governments—to access funds up to an approved limit on demand, repay principal at their discretion, and redraw as needed, with interest accruing solely on the drawn amount rather than the full limit. This contrasts with term loans by offering ongoing flexibility without repeated applications, though minimum payments are typically required monthly, often covering interest plus some principal. LOCs exist in secured forms, collateralized by assets like (e.g., home equity lines of credit, or HELOCs), which generally carry lower rates due to reduced lender risk, and unsecured variants, which depend on scores and income verification, commanding higher interest rates averaging 8-15% for personal lines as of 2024. Borrowers face variable rates tied to benchmarks like the , exposing them to fluctuations; for instance, rates rose from around 4% in 2022 to over 8% by mid-2023 amid hikes. Consumer LOCs proliferated during the mid-20th-century expansion of finance, building on postwar innovations in credit assessment and , with HELOC originations surging from negligible levels in the to $200 billion annually by the early as values climbed. This growth facilitated for emergencies or investments but amplified vulnerabilities, as empirical patterns reveal borrowers increasing draws during distress, with defaulted entities utilizing up to 50-70% more of their limits than non-defaulting peers in corporate cases. U.S. utilization hovered around 28-30% from 2019 to 2022, reflecting moderate but persistent , before edging higher post-pandemic. Delinquency rates on , a proxy for LOC performance, averaged 4.3% pre-2020 but spiked to 11.1% in Q4 2009 during , underscoring sensitivity to economic downturns. While LOCs provide advantages in cash flow management—allowing borrowers to bridge shortfalls without depleting savings—their structure incentivizes habitual borrowing, as high variable rates (often exceeding 20% for unsecured personal lines) compound on unpaid balances, fostering cycles where new draws fund interest rather than principal reduction. This dynamic contributed to the 2008 crisis, where nonfinancial firms drew down $500-800 billion in committed lines amid fears, transforming exposures into immediate bank liabilities and accelerating freezes. Such episodes highlight causal risks from overextended access: empirical evidence links pre-crisis booms, including liberalized LOC commitments, to heightened default probabilities, with utilization surges preceding 20-30% drops in lending during contractions. Policies prioritizing broad expansion, often without commensurate borrower education on compounding costs, have empirically correlated with elevated household indebtedness, reaching $1.1 trillion in revolving balances by 2023.

Manufacturing and Engineering

Length of Cut

In , particularly milling operations, the length of cut (LOC)—also known as axial depth of cut—refers to the axial penetration of the cutting tool into the workpiece, determining the volume of material removed per pass and influencing chip formation efficiency. This parameter is distinct from radial depth of cut, focusing on tool engagement along its axis to optimize chip load, where chip thickness is calculated as feed rate divided by the number of tool flutes, scaled by LOC to manage heat generation and tool deflection. LOC is optimized using empirical models such as Taylor's tool life equation, extended to incorporate depth effects: VT^n = C, where V is cutting speed, T is tool life, n and C are material-specific constants, and adjustments for LOC via modified forms like Colding's model account for axial engagement to predict wear in side milling of steels like C45E. Increasing LOC boosts material removal rates but must balance against power consumption and tool breakage, with formulas deriving optimal values from spindle power limits and workpiece geometry—typically 0.5 to 2 times tool diameter for roughing in aluminum alloys. Since the 1980s expansion of computer numerical control (CNC) systems, precise LOC programming has enhanced by enabling deeper cuts in multi-axis setups, reducing cycle times by up to 30% in high-volume production compared to manual methods. However, excessive LOC without rigidity analysis exacerbates vibrations (chatter), arising from dynamic cutting forces and tool overhang, which accelerate flank wear, degrade to Ra > 3.2 μm, and cause premature tool failure via amplification. For difficult-to-cut alloys like or NiTi introduced or refined post-2020, sustainability demands adjusted LOC under minimum quantity lubrication (MQL) or cryogenic conditions to minimize energy use—reducing by 80% and by 25% via shallower engagements that limit thermal loads without coolant dependency. These adaptations prioritize verifiable metrics like power draw (e.g., 20-40% lower in dry regimes) over , aligning with causal factors in wear mechanics for alloys exhibiting high strength-to-weight ratios.

Arts, Entertainment, and Media

L.O.C. (Rapper)

Liam Nygaard O'Connor (born July 10, 1979), professionally known as L.O.C., is a Danish rapper and songwriter recognized as one of the country's most commercially successful artists. Born in to a Danish mother and father, he initially gained attention as a member of hip-hop groups before launching a solo career that established him as Denmark's best-selling rapper, with aggregate album sales exceeding 380,000 units. His music blends introspective narratives with urban themes, often reflecting personal and societal challenges, which resonated strongly in the early Danish scene. L.O.C. released his debut solo album, Dominologi, in 2001, marking his transition to independent prominence, followed by breakthrough works like Inkarneret (2004), which achieved platinum status for sales over 45,000 copies in . Subsequent albums such as (2005) and Melankolia Si**r, XxxCouture (2008) also earned platinum certifications and critical acclaim, with the latter winning at the Danish Music Awards. These releases propelled multi-platinum equivalent success through high domestic sales and radio play, solidifying his role in elevating Danish-language rap to mainstream viability. Collaborations with producers like Rune Rask and appearances on international platforms, including Tech N9ne's projects, expanded his reach beyond . Despite achieving widespread popularity, L.O.C.'s trajectory has faced scrutiny from some hip-hop purists who contend that integration compromises the genre's raw, underground ethos, though his consistent output counters claims of fading relevance. Post-2020, he maintained momentum with Ekkokammer (2020), awarded Danish Hip-Hop Release of the Year by Gaffa, and subsequent singles like "Hvassådair" (2023), demonstrating sustained artistic evolution amid evolving industry dynamics. His enduring sales and underscore a career trajectory defined by commercial endurance rather than fleeting trends.

People

Individuals Named Loc or Variants

Nguyễn Lộc (May 24, 1912 – 1960) was a martial artist credited with founding , a hybrid combat system integrating bare-hand techniques, wrestling, and weaponry to foster physical discipline and cultural resilience during colonial-era . Originating from Huu Bang village in Thạch Thất district, he established the art in around 1938, emphasizing principles of ethical and national unity, which spread through dojos and influenced subsequent generations of practitioners. Loc Nguyen served as director of the Immigration and Refugee Division at of from 1980 until his retirement in 2021, managing resettlement programs that assisted over 10,000 refugees and other immigrants through , , and services amid post-Vietnam diaspora challenges. His tenure focused on bridging community needs with federal policies, earning recognition for sustained in refugee . Other individuals bearing the name Loc, such as academics in like Loc at the at —who has contributed to inverse problems and with over 1,300 scholarly citations—hold prominence in specialized fields but lack broader public notability comparable to the above figures.

Other Uses

Miscellaneous Technical and Regional Terms

An Lộc is a town and district in , , serving as a provincial border location historically significant for its role in the 1972 . During the , from April 13 to July 20, of the Republic of Vietnam (ARVN) forces, supported by U.S. airpower, withstood a by two North divisions equipped with tanks, halting their advance toward Saigon after over 30,000 enemy troops initially overran forward positions. The defense involved that inflicted heavy casualties on attackers, preserving South Vietnamese control in III Corps Tactical Zone despite intense urban combat and artillery bombardment. Loc-Envel denotes a rural commune in the department of , northwestern , with a population under 1,000 residents focused on agricultural and historical sites typical of Breton localities. The name incorporates "Loc," a Breton term for a sacred place or hermitage, reflecting regional linguistic heritage in communes like Loc-Envel that maintain traditional administrative structures. In , lab-on-a-chip (LOC) refers to microfluidic systems that integrate multiple functions—such as , , and detection—onto a single miniaturized chip, typically using channels under 1 mm in scale for precise fluid handling. Emerging in the late 1990s, LOC devices enable rapid diagnostics and by leveraging principles like and , with applications in for diseases via reduced reagent volumes and faster reaction times compared to conventional labs.