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Pore

A pore is a minute opening or channel in a biological membrane, cellular structure, or tissue surface that facilitates the selective passage of substances such as ions, water, gases, nutrients, or waste products essential for cellular function, secretion, and environmental exchange.^[1] In animals, pores include sweat pores in the skin, which enable thermoregulation through perspiration, and nuclear pores embedded in the nuclear envelope, which control macromolecular transport between the nucleus and cytoplasm to maintain genetic regulation and cellular homeostasis.^[2]^[3] In plants, stomatal pores on leaf surfaces, flanked by guard cells, regulate gas exchange for photosynthesis and transpiration while minimizing water loss.^[4] These structures vary in size from nanometers in ion channels to micrometers in epidermal openings, with their permeability governed by protein complexes or mechanical properties that ensure efficient yet controlled diffusion or active transport.^[5] Pores underpin fundamental life processes across organisms, from microbial nutrient uptake to human sensory and excretory functions, and their dysfunction can lead to disorders such as cystic fibrosis or impaired wound healing.^[6]

Biological contexts

Pores in animals and microorganisms

In mammalian skin, eccrine sweat glands terminate in ductal pores with an inner diameter of approximately 60–80 μm, facilitating the secretion of hypotonic sweat that evaporates to dissipate heat and maintain thermoregulation during elevated metabolic demands.^[7] ^[8] This evaporation process relies on pore-mediated fluid delivery to the skin surface, where rates can reach 1.5–2.5 L/hour under maximal conditions, directly influencing cooling efficiency through surface area exposure and vapor pressure gradients.^[9] Adjacent sebaceous glands open into hair follicles via associated pores, secreting sebum composed of triglycerides, fatty acids, and waxes to lubricate the skin, prevent desiccation, and form a protective barrier against environmental stressors.^[10] ^[11] Pore dysfunction in these systems contributes to pathological states; for instance, in acne vulgaris, androgen-driven sebaceous gland hyperplasia leads to sebum overproduction exceeding 2–3 times normal levels, combining with hyperkeratinization to clog follicular pores and promote Propionibacterium acnes proliferation, inflammation, and lesion formation.^[12] ^[13] Empirical observations link pore occlusion to reduced sebum outflow, with histological studies showing infundibular dilation and microcomedone buildup as early causal events in lesion development.^[11] In aquatic animals such as teleost fish, gill structures—including branchial arches with lamellar pores and interlamellar spaces—enable gas exchange by channeling water over a vast surface area exceeding 0.1 m²/kg body mass, where oxygen diffuses across thin epithelia driven by partial pressure gradients between ventilated water (typically 100–150 mmHg PO₂) and deoxygenated blood (20–40 mmHg PO₂).^[14] ^[15] Ventilation-perfusion matching sustains these gradients, with empirical measurements indicating diffusion limitation accounts for 70–80% of oxygen uptake efficiency in active species, while pore-like lamellar channels minimize boundary layer resistance to flow.^[16] Disruptions, such as mucus accumulation narrowing interlamellar pores, reduce exchange rates by up to 50% in hypoxic conditions.^[15] In microorganisms, particularly Gram-negative bacteria, outer membrane porins form trimeric β-barrel channels with aqueous pores of 1–2 nm diameter, permitting passive diffusion of hydrophilic nutrients like sugars and amino acids (up to ~600 Da) essential for growth in nutrient-limited environments.^[17] ^[18] These structures, exemplified by OmpF and OmpC in Escherichia coli, maintain selective permeability, with expression levels modulating uptake rates; downregulation reduces nutrient influx by 20–50% under stress.^[19] Porin alterations, such as mutations shrinking pore size or reducing expression, confer antibiotic resistance by limiting β-lactam and fluoroquinolone entry, as evidenced by minimum inhibitory concentrations increasing 4–16-fold in porin-deficient strains.^[20] ^[19] This mechanism underscores causal trade-offs, where impaired porin function elevates resistance but compromises fitness in competitive niches requiring rapid nutrient acquisition.^[21]

Pores in plants and fungi

Stomatal pores, formed by pairs of guard cells in the epidermis of plant leaves and stems, facilitate gas exchange essential for photosynthesis by allowing carbon dioxide influx while minimizing water loss through transpiration. Guard cells adjust pore aperture via turgor pressure changes in response to environmental cues, including elevated atmospheric CO2 levels that trigger closure to conserve water, and light intensity that promotes opening through photosynthetic signals. This regulation optimizes photosynthetic efficiency, as stomatal conductance directly influences intercellular CO2 concentration and net CO2 assimilation rates. Typical stomatal densities range from hundreds to over 1,500 pores per square millimeter in mature leaves, correlating with higher conductance and up to 30% increased photosynthetic rates under high-light conditions in density-enhanced variants.^[22]^[23]^[24]^[25] Lenticels serve as specialized pores in the bark of woody stems, roots, and some fruits, enabling aeration by permitting oxygen entry and carbon dioxide efflux through otherwise impermeable periderm layers. These structures, composed of loosely packed cells with thin walls and intercellular spaces, enhance gas permeability in submerged or bark-covered tissues, supporting respiration in cambial and cortical regions. Lenticel density and size vary by species and environmental demands, with higher densities observed in wetland-adapted plants to compensate for hypoxic soils.^[26]^[27] In fungi, particularly within the order Polyporales, pores in fruiting bodies (basidiocarps) function primarily for spore dispersal, with tubular hymenophores lined by spore-producing basidia opening to the exterior for wind-mediated release. These poroid structures, numbering thousands per cap in species like Ganoderma, facilitate efficient reproductive dissemination by exposing spores to airflow while protecting internal tissues. Unlike plant stomata, fungal pores lack dynamic regulation but contribute to aeration in compact fruiting bodies by allowing passive gas diffusion through the porous architecture. Occlusion of plant pores by pollutants such as ozone or particulate matter, or by pathogen-induced closure, reduces transpiration rates by 20-50% in field studies, impairing cooling and nutrient uptake, whereas fungal pore blockage from environmental debris limits spore viability and dispersal success.^[28]^[29]^[30]

Cellular and molecular pores

Nuclear pore complexes (NPCs) form large aqueous channels spanning the nuclear envelope, enabling selective transport of molecules between the cytoplasm and nucleus. Each NPC consists of multiple copies of approximately 30 nucleoporin proteins, forming a scaffold with a central transport channel of roughly 9-40 nm in diameter, depending on conformational states and cellular context, through which passive diffusion occurs for molecules smaller than about 40 kDa while larger cargoes require facilitated transport mediated by karyopherins.^[31] The selectivity arises from intrinsically disordered FG-nucleoporin repeats (phenylalanine-glycine motifs) that line the channel, creating a permeable barrier akin to a hydrogel that permits rapid diffusion of small, hydrophilic molecules via transient hydrophobic interactions, while excluding non-specific macromolecules through entropic exclusion and specific binding to transport receptors.31127-3) This mechanism ensures efficient nucleocytoplasmic exchange, with empirical rates supporting up to 1,000 translocations per NPC per second under physiological conditions, grounded in the principles of Brownian motion and size-based sieving refined by molecular recognition.^[32] At the plasma and organelle membranes, ion channels serve as highly selective molecular pores that facilitate rapid, passive diffusion of ions down electrochemical gradients, maintaining cellular homeostasis through precise control of membrane potential and osmotic balance. For instance, voltage-gated potassium channels, such as those structurally resolved by X-ray crystallography and cryo-EM, feature narrow selectivity filters where dehydrated K⁺ ions coordinate with carbonyl oxygens, enabling conductance rates of approximately 10⁸ ions per second per channel as measured by patch-clamp electrophysiology, far exceeding diffusive limits for non-selective pores due to optimized energy barriers for permeation.^[33] Gating mechanisms, involving conformational changes in transmembrane helices triggered by voltage or ligands, open and close the pore to regulate flux, with mutations disrupting this selectivity linked to disorders like episodic ataxia; this selectivity stems from thermodynamic favorability of ion dehydration and rehydration within the filter, rejecting smaller Na⁺ ions despite similar hydration energies.^[34] Aquaporins exemplify water-specific pores, forming tetrameric channels in membranes with hourglass-shaped monomers that conduct water molecules in single file at rates up to 3 × 10⁹ molecules per second per monomer, as determined by biophysical assays and molecular dynamics simulations. Cryo-EM structures reveal a narrow constriction site (~2-3 Å) flanked by asparagine-proline-alanine (NPA) motifs that orient water dipoles for proton exclusion via Grotthuss mechanism disruption, ensuring uncharged H₂O permeation while barring hydronium ions and other solutes through electrostatic and steric constraints.^[35] ^[36] In chloride channels like CFTR, pore defects from mutations such as ΔF508 (prevalent in ~70% of cystic fibrosis cases) impair anion conductance by altering folding, trafficking, or gating, reducing Cl⁻ flux and causing mucus accumulation in airways; patch-clamp studies confirm diminished open probability and altered selectivity, underscoring causal links between pore dysfunction and disease pathology without invoking secondary effects.^[37] ^[38] These molecular pores collectively demonstrate how structural precision enables high-throughput, selective diffusion, with empirical kinetics validating first-principles predictions of flux limited by activation energies rather than viscosity alone.

Technological applications of nanopores

Nanopores, typically 1-2 nm in diameter, enable single-molecule sequencing by detecting disruptions in ionic current as DNA or RNA molecules translocate through a voltage-applied membrane-embedded channel.^[39] Oxford Nanopore Technologies employs biological protein nanopores, such as engineered variants of Mycobacterium smegmatis porin A, in devices like MinION and PromethION for real-time analysis, where nucleotide-specific current blockades—termed "squiggles"—are basecalled via machine learning algorithms.^[40] Solid-state nanopores, fabricated from materials like silicon nitride, offer potential advantages in durability and scalability over protein nanopores but remain largely experimental for commercial sequencing due to challenges in achieving comparable resolution and throughput.^[41] Direct RNA sequencing (DRS) using these nanopores sequences native RNA strands without conversion to cDNA, preserving modifications like methylation for simultaneous detection alongside sequence data.^[42] In 2025 updates, improved basecallers such as Dorado enhanced DRS accuracy, enabling de novo identification of modifications including N6-methyladenosine (m6A) and pseudouridine, with per-read accuracies approaching Q20 (99.9% raw read accuracy) in optimized protocols for mRNA and viral RNA.^[43] This facilitates isoform resolution and transcript complexity analysis, outperforming indirect methods in capturing full-length native structures, though throughput remains limited compared to DNA sequencing kits.^[44] Beyond nucleic acids, nanopore applications extend to antimicrobial resistance (AMR) profiling, where long-read sequencing resolves plasmid structures and genetic contexts of resistance genes in real-time from clinical isolates or metagenomes.^[45] A 2025 study demonstrated nanopore-based identification of AMR determinants in bovine mastitis pathogens within hours, aiding rapid therapeutic decisions.^[46] In proteomics, advances toward protein sequencing leverage nanopore sensing of amino acid-specific blockades, with 2025 milestones including single-peptide fingerprinting and post-translational modification detection, though full proteome coverage awaits resolution of translocation control and signal discrimination issues.^[47]^[48] Despite these capabilities, nanopore sequencing exhibits systematic error rates of 1-5% in high-quality modes, primarily from homopolymer regions where consecutive identical bases produce indistinguishable current levels, leading to insertion/deletion errors not easily mitigated by consensus alone.^[49] These limitations contrast with short-read technologies like Illumina, which offer >99.9% accuracy but struggle with repeat resolution; hybrid approaches combining nanopore long reads with short-read polishing reduce effective errors below 0.5% for genome assembly.^[50] Such trade-offs underscore nanopores' strength in structural variant detection over base-level precision in repetitive sequences.^[51]

Physical and materials science contexts

Pore structure and morphology

Pores in solid materials are classified by the International Union of Pure and Applied Chemistry (IUPAC) based on size: micropores with widths less than 2 nm, mesopores between 2 and 50 nm, and macropores exceeding 50 nm.^[52] This classification derives from adsorption behavior and capillary phenomena, with micropores exhibiting enhanced potential fields and macropores behaving like bulk fluid spaces.^[53] Pore morphology encompasses shapes such as cylindrical (open-ended tubes), ink-bottle (wide body with narrow neck restricting access), and slit-like forms, which determine connectivity within the void network.^[54] Interconnected pore networks feature branching pathways, quantified by tortuosity—a measure of path deviation from straight lines, typically ranging from 1.4 to 1.5 in cementitious materials and increasing with irregularity.^[55] These architectures influence mass transport, with ink-bottle pores showing hysteresis in adsorption-desorption due to neck trapping.^[54] In activated carbons, pores form disordered, hierarchical networks dominated by micropores (up to 80% of volume) alongside mesopores, yielding total pore volumes exceeding 1 cm³/g.^[56] Zeolites exhibit crystalline micropore frameworks with uniform channels (e.g., 0.3-1 nm diameters) arranged in regular lattices.^[57] Aerogels achieve extreme porosity, with void fractions often surpassing 90%, primarily through interconnected mesopores and macropores that minimize solid mass while maintaining structural integrity.^[58] Recent analyses of bioengineered scaffolds highlight distinctions between regular (e.g., Voronoi lattices) and irregular pore morphologies, where irregularity—deviations in shape and interconnectivity—alters local stress distributions and fluid flow patterns without uniform scaling.^[59] In Ti6Al4V scaffolds, irregular pores (e.g., 300-600 µm) contrast with regular counterparts by introducing variable curvatures that enhance network heterogeneity.^[60]

Physical properties and characterization methods

Porosity, defined as the fraction of void volume to total volume (φ = V_void / V_total), is a fundamental physical property of porous materials that directly influences fluid storage and transport capacity. Higher porosity generally enhances permeability by providing more void space for flow, though this is modulated by interconnectivity; for instance, isolated pores reduce effective transport despite high φ values. Pore size distribution, characterizing the range and frequency of pore diameters, affects capillary forces and filtration efficiency, with narrower distributions in uniform materials like zeolites promoting consistent performance.^[61]^[62] Characterization of porosity and pore size distribution commonly employs mercury intrusion porosimetry (MIP), which extrudes mercury under increasing pressure to measure intrusion volume, yielding pore volumes and diameters via the Washburn equation assuming cylindrical pores (d = -4γ cosθ / P, where γ is surface tension, θ contact angle, P applied pressure). MIP effectively probes mesopores (2–50 nm) and macropores (>50 nm) up to ~400 μm, revealing distributions that correlate with material permeability—broader distributions often indicate higher tortuosity and reduced flow efficiency. Complementary nitrogen adsorption at 77 K assesses micropores (<2 nm) and mesopores, with the Brunauer-Emmett-Teller (BET) method deriving specific surface area (S_BET) from multilayer adsorption isotherms, where S_BET = (V_m * N_A * σ) / M, V_m monolayer volume, σ adsorbate cross-section.^[63]^[64]^[65] Specific surface areas in high-porosity materials, such as activated carbons, can exceed 2000 m²/g, enabling strong capillary action via heightened interfacial energy and Young-Laplace pressure (ΔP = 2γ cosθ / r), which drives fluid imbibition and influences wetting behavior. Tortuosity (τ), quantifying deviation of pore paths from straight lines (τ = L_e / L, effective vs. straight path lengths), inversely scales permeability by elongating flow paths; empirical models link τ to porosity as τ ≈ 1 / φ^m (m ~0.5–1), with higher τ reducing diffusive and convective transport. Permeability (k) in laminar flow regimes follows Darcy's law, v = - (k / μ) ∇P (v superficial velocity, μ viscosity), where k integrates porosity, tortuosity, and surface area, as in the Kozeny-Carman relation k ≈ (φ^3 / (5 S^2 (1-φ)^2 τ)), causal for predicting reduced k in tortuous, low-φ media despite open pores.^[66]^[61]^[67] Recent advances employ pair distribution function (PDF) analysis from total X-ray scattering to probe local atomic correlations in disordered porous frameworks, G(r) = 4πr [ρ(r) - ρ_0], revealing structural transitions like framework collapse under stress without relying on long-range crystallinity. A 2023 study demonstrated PDF's utility in tracking phase evolutions in porous materials, linking local bond disruptions to macroscopic property shifts such as diminished porosity during deformation. This method causally connects nanoscale disorder to bulk metrics like reduced permeability from altered tortuosity in transitioning structures.^[68]^[68]

Applications in geology and engineering

In sedimentary rocks, pore spaces serve as primary storage for hydrocarbons in geological reservoirs, where interconnected porosity enables the accumulation and migration of oil and gas. Productive reservoirs typically exhibit porosities between 5% and 30%, which directly influence the volume of recoverable fluids, though extraction efficiency also depends on permeability and fluid saturation.^[69]^[70] For instance, sandstone and carbonate formations with these porosity levels have supported major oil fields, such as those in the Permian Basin, where enhanced recovery techniques target pore-held reserves to achieve yields up to 50% of original oil in place under optimal conditions.^[71] Engineered porous media replicate natural pore structures for industrial applications, including filtration systems and thermal management. Metal foams, such as open-cell aluminum variants with pore sizes of 1-5 mm, are deployed in heat exchangers and dissipators, where their high surface-area-to-volume ratios facilitate convective heat transfer rates exceeding those of solid metals by factors of 2-5.^[72] In insulation, closed-cell foams minimize conduction through trapped gas in pores, achieving thermal conductivities as low as 0.03 W/m·K, as utilized in aerospace components for lightweight, efficient barriers.^[73] Pore connectivity models underpin simulations of fluid dynamics in geothermal reservoirs and aquifers, predicting migration pathways for heat and water extraction. Pore-network approaches quantify relative permeability and capillary effects, enabling forecasts of flow rates in fractured-porous systems, such as those in enhanced geothermal systems where connectivity governs injectivity indices up to 0.1-1.0 m³/min per well.^[74]^[75] These models have informed aquifer storage and recovery projects, like those in sandstone aquifers with dual-porosity behavior, optimizing recharge volumes by accounting for matrix-fracture interactions.^[76] Mining-induced subsidence often results from pore collapse in overburden strata, leading to volumetric compaction and surface deformation. In coal extraction, such as in fully mechanized top-coal caving operations, overburden pore evolution progresses through collapse and compaction zones, with subsidence magnitudes reaching 1-5 meters in cases like those documented in Chinese coal fields, where extraction ratios above 80% trigger fractal-patterned fractures.^[77]^[78] Case studies from lead-zinc mines demonstrate that backfilling tailings into voids can mitigate collapse by 50-70%, preserving structural integrity and reducing risks to overlying infrastructure.^[79]

Chemical contexts

Pores in adsorbents and catalysts

Microporous zeolites exhibit shape-selective catalysis due to their uniform pore apertures, typically 0.3-1 nm in diameter, which restrict access to internal active sites based on reactant molecular dimensions.^[80] This sieving effect favors linear over branched hydrocarbons in reactions like alkylation or cracking, where only compatible shapes diffuse efficiently to acid sites, enhancing product selectivity and minimizing side reactions.^[81] Pore confinement also influences reaction kinetics by imposing transition state shape selectivity, as demonstrated in studies of MFI zeolites where subtle pore variations alter diffusion rates and catalytic turnover.^[82] Metal-organic frameworks (MOFs) extend this principle with designer pores tunable from sub-0.5 nm to over 2 nm, enabling precise control over chemo- and shape-selective processes such as oxidation or hydrogenation.^[83] The modular linker chemistry allows integration of catalytic metal nodes within pores, where aperture size dictates substrate entry and orientation, boosting yields in tandem reactions; for instance, UiO-67 variants show enhanced activity for larger-pore systems in selective reductions.^[84] Hierarchical MOF architectures further optimize kinetics by balancing micropore selectivity with mesopore transport, reducing diffusion limitations in sustained catalysis.^[85] In adsorbents like activated carbon, hierarchical pores—spanning micropores (<2 nm) for high-affinity physisorption and mesopores (2-50 nm) for mass transport—facilitate efficient volatile organic compound (VOC) removal from aqueous streams via dispersion forces.^[86] Micropores dominate binding of nonpolar VOCs like benzene through enhanced van der Waals interactions in confined spaces, with optimal distributions yielding capacities up to 200-500 mg/g under ambient conditions.^[87] Pore wall chemistry modulates selectivity; recent inverse design simulations reveal that patterned functional groups on walls can amplify solute discrimination by altering local binding energies, informing catalyst engineering for targeted adsorption-desorption cycles.^[88] IUPAC classifications refine pore roles in these materials, distinguishing ultramicropores (<0.7 nm) for ultrahigh selectivity in physisorption due to intensified potential fields, as opposed to supermicropores (0.7-2 nm) favoring faster kinetics.^[89] In catalysts, wall topology and chemistry causally dictate intraparticle gradients, with 2024 active learning models showing roughness-independent effects on selectivity via optimized group distributions.^[90] This underpins advances in porous solids where pore engineering directly correlates with reaction efficiency, as pore heterogeneity tunes surface-reactant interactions without external modifiers.^[91]

Personal names

As a given name

Pore is a rare given name of Georgian origin, primarily attested in the Caucasus region, particularly associated with the Signagi Municipality.^[92] Its usage appears limited, with few documented instances beyond historical figures from Georgia.^[93] The most notable bearer is Pore Mosulishvili (July 20, 1916 – December 3, 1944), a Soviet soldier from Kvemo Machkhaani, Georgia, who served as a partisan in the Italian resistance during World War II.^[93] Recruited into the Red Army in 1939, he was captured by German forces during the 1941 invasion but escaped and joined an Italian partisan brigade, where he rose to command a unit of sixteen fighters.^[93] On December 3, 1944, surrounded by Nazi troops near Forno, Italy, Mosulishvili refused to surrender and threw himself on a grenade to shield his comrades, enabling their escape; all survived the incident.^[94] For this act of self-sacrifice, he was posthumously awarded the title Hero of the Soviet Union and Italy's Gold Medal of Military Valor.^[94] In Georgia, his legacy includes a house museum in his birthplace exhibiting personal artifacts, medals, documents, and ethnographic items, as well as streets named in his honor.^[95]

As a surname

The surname Pore is most prevalent in India, where it is held by approximately 14,555 individuals, comprising about 73% of global bearers according to distribution data.^[96] Within India, it is concentrated in Maharashtra (59% of cases), followed by states such as Uttar Pradesh and Madhya Pradesh, often linked to historical occupational roles in labor and trade among regional communities.^[96] ^[97] In the United States, Pore appears in census records dating to 1840, with early bearers primarily engaged in manual occupations; by 1940, 25% of men with the surname worked as laborers and others as truck drivers, reflecting migration patterns from Europe and later Asia.^[98] The name ranks around 30,000th in U.S. frequency, with a diverse racial distribution including 57% White and notable Asian representation.^[99] Notable bearers include Ryan Pore (born September 23, 1983), an American former professional soccer forward who played in Major League Soccer for teams including the Portland Timbers, accumulating six goals in his debut season and earning USSF D-2 Pro League recognition.^[100] He later transitioned to coaching, serving as head men's soccer coach for the Kansas City Roos since 2020, with a record of 19-28-17 through 2023.^[101]

Geographical locations

Settlements and regions named Pore

Poreč, located on the western coast of the Istrian Peninsula in Croatia, originated as the Roman colony of Colonia Iulia Parentium around 10 BC, serving as a key port in the Adriatic.^[102] The settlement evolved under Byzantine, Venetian, and later Austro-Hungarian rule, with Slavic inhabitants arriving in the 7th century AD, leading to the modern Croatian name derived from the Latin root.^[103] Its historic center includes the 6th-century Euphrasian Basilica, part of an episcopal complex recognized by UNESCO as a World Heritage Site in 1997 for exemplifying early Christian basilican architecture with preserved mosaics and marblework.^[104] In the Indian subcontinent, "pore" appears as an anglicized variant of the Sanskrit suffix "pura" or "pur," denoting a town or fortified settlement, commonly appended to founders' names or descriptive terms in place names.^[105] Examples include Firozpur (formerly Ferozepore) in Punjab, established in 1355 by Sultan Firoz Shah Tughlaq of the Delhi Sultanate as a military outpost on the Sutlej River, which grew into a district headquarters with a population exceeding 1.1 million by 2011.^[106] Beypore, a coastal town in Kerala, traces to ancient maritime trade routes, known since the 19th century for traditional shipbuilding in dhows and its role as a port under the Zamorin rulers of Calicut.^[106] Jeypore (also spelled Jaypur) in Odisha, founded in 1641 by King Vir Vikram Dev of the Nag dynasty, developed as a regional center for tribal crafts and agriculture, with the "pore" element reflecting the pervasive "pur" convention in eastern Indian toponymy.^[105] Singapore's name evolved from Malay "Singapura," coined in the 14th century legendarily after a prince sighting a lion (singa) on the island, with "pura" (city) rendered as "pore" in 19th-century British colonial orthography, though the modern city-state's etymology emphasizes its role as a trading entrepôt rather than a direct "Pore" designation.^[106] Pore is a rural municipality in Colombia's Casanare Department, established on December 13, 1779, by Spanish settlers amid llanos grasslands, primarily supporting cattle ranching and oil-related activities with a 2005 population of about 2,800.^[107]

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The 2.5 Å resolution structure of AqpZ suggests aquaporin selectivity results both from a steric mechanism due to pore size and from specific amino acid ...Missing: cryo- | Show results with:cryo-
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Cystic fibrosis transmembrane conductance regulator chloride ...
Dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel causes cystic fibrosis, while inappropriate activity of this ...
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How do CFTR mutations cause cystic fibrosis? - ScienceDirect.com
The key defect in cystic fibrosis is loss of chloride conductance, but mutations of the cystic fibrosis gene product, the CFTR, have multiple effects on cell ...
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How nanopore sequencing works | Oxford Nanopore Technologies
When a molecule passes through a nanopore, the current is disrupted to produce a characteristic 'squiggle'. The squiggle is then decoded using basecalling ...
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Nanopore sequencing technology, bioinformatics and applications
Nov 8, 2021 · In an electrolytic solution, a constant voltage is applied to produce an ionic current through the nanopore such that negatively charged single- ...
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An Introduction to Nanopore Sequencing: Past, Present, and Future ...
In this review, we provide a general introduction to nanopore sequencing principles, discussing biological and solid-state nanopore developments.
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Direct RNA sequencing (SQK-RNA004)
Sep 18, 2025 · This protocol describes how to carry out sequencing of native RNA using the Direct RNA Sequencing Kit (SQK-RNA004).Missing: improvements | Show results with:improvements
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Evaluation of Nanopore direct RNA sequencing updates for ...
May 4, 2025 · This update included an improved basecaller (Dorado) for increased sequencing accuracy, and ionic current models for de novo detection of four ...
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Nanopore direct RNA sequencing of human transcriptomes reveals ...
Jun 11, 2025 · Our study presented a rich dRNA-seq data resource that has been validated and can be further exploited to inquire into the complexity of RNA modifications.
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Optimizing Sample Preparation for Direct Nanopore Sequencing to ...
Aug 19, 2025 · Optimizing Sample Preparation for Direct Nanopore Sequencing to Enable Rapid Pathogen and Antimicrobial Resistance Profiling in Bovine Mastitis.
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Oxford Nanopore's roadmap to proteomics
May 20, 2025 · Oxford Nanopore unveils its pioneering roadmap to full protein sequencing, advancing real-time, direct proteomics for transformative ...
[48]
Nanopore protein sequencing achieves significant new milestones
In response to this recognized need, the last five years have seen rapid advances toward the potential use of nanopores for sequencing proteins. In recent work ...
[49]
Sequencing DNA with nanopores: Troubles and biases - PMC
Oct 1, 2021 · In particular, low-GC reads have fewer errors than high-GC reads (about 6% and 8% respectively). The error profile for homopolymeric regions or ...
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Homopolish: a method for the removal of systematic errors in ...
Mar 31, 2021 · Owing to higher error rates, errors on the genome are corrected via neural networks trained by Nanopore reads. However, the systematic errors ...
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[PDF] 2015-IUPAC-Technical-Report.pdf - 3P Instruments
The process which then occurs is micropore filling, as distinct from the surface coverage which takes place on the walls of open macropores or mesopores. In the ...
[53]
Pore structure characterization and its significance for gas ...
The other was proposed by IUPAC [20], which divided pores into micropores (<2 nm), mesopores (2–50 nm) and macropores (>50 nm). Considering the gas behavior in ...
[54]
[PDF] porosity and specific surface area measurements for solid materials
ink bottle pore: a narrow necked open pore interconnected pore: pore that communicates with other pores. 73. Page 86. Porosity & Specific Surface Area ...<|separator|>
[55]
Characterizing connectivity and tortuosity of pore network based on ...
Sep 15, 2024 · The results show that the pore connectivity of the mortar ranges from 32 % to 52 %, and the tortuosity ranges from 1.428 to 1.542. The pore ...
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Investigation on pore structure regulation of activated carbon ...
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Modulating the porosity of carbons for improved adsorption of ...
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The Pore Structure Determination of Carbon Aerogels | Adsorption
The predominant pores in carbon aerogels were mesopores and the percentage of micropores was in the range of 5 to 10% of the total pore volume.
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Large-pore-size Ti6Al4V scaffolds with different pore structures for ...
The irregular pore size scaffold has better osteogenesis and vascularization effect than the regular pore size scaffold. •. Within the pore size range of our ...
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How to measure the materials porosity - ATRIA Innovation
The distribution of pores and their characteristics defines the permeability of the material, that is, its ability to store fluids, thus conditioning its ...
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Characterisation of porous solids using integrated nitrogen sorption ...
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BET Surface Area Analysis & BJH Pore Size & Volume ... - Lucideon
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Oct 24, 2016 · The CNT material has extremely large discrepancies between the BET and the DFT surface areas. For example, a BET surface area of 7 m2/g was 35 m2/g on DFT.What are the materials having a BET surface area higher than 2000 ...Is BET wothwhile to find porosity? - ResearchGateMore results from www.researchgate.netMissing: m²/ | Show results with:m²/
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Understanding porous materials with pair distribution functions
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Hydrocarbon reservoirs are subsurface porous rocks containing oil and/or gas, with sufficient porosity, permeability, and saturation to be an economic resource.
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Characterization and Analysis of Porosity and Pore Structures
Jan 1, 2015 · Porosity plays a clearly important role in geology. It controls fluid storage in aquifers, oil and gas fields and geothermal systems.
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Modeling Oil Recovery for Mixed Macro- and Micro-Pore Carbonate ...
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Heat Dissipation of Open-Cell-Type Aluminum Foams Manufactured ...
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Commercial Applications of Metal Foams: Their Properties and ... - NIH
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A coupled thermal–hydrological–mechanical model for geothermal ...
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[76]
A pore-scale mathematical modeling of fluid-particle interactions
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[77]
Research on the collapsing pattern of overburden rock and pore ...
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[78]
Investigation on overburden failure and subsurface subsidence ...
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[79]
a case study of lead-zinc mine in Inner Mongolia, China - Frontiers
This paper proposes tailings backfill technology to mitigate surface subsidence and provides an alternative disposal method for tailings generated during ore ...
[80]
Shape-selective catalysis in zeolites - ScienceDirect.com
Small and uniform pores characterize zeolite catalysts. If most catalytic sites are inside this pore structure and if the pores are small, the fate of ...
[81]
Influence of Nanoscale Intimacy and Zeolite Micropore Size on the ...
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[82]
Recent advances in shape selectivity of MFI zeolite and its effect on ...
MFI zeolite characterized by uniform pore size, adjustable acidity, and high-temperature resistance has a broad application prospect in catalytic reactions.
[83]
Metal–organic frameworks as catalytic selectivity regulators for ...
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[84]
Metal‐Organic Framework–Specific Catalysis - Chemistry Europe
Feb 19, 2025 · The activity of the MOF-based catalysts could be enhanced by moving to larger pore MOF systems such as UiO-67 (MOF structure depicted in Figure ...3 Controlling... · 5 Stabilizing Unusual Active... · 7 Controlling The Extended...
[85]
Pore Engineering in Metal–Organic Frameworks for Enhanced ...
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A Concise Review on Porous Adsorbents for Benzene and Other ...
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Functionalized Activated Carbon for Competing Adsorption of ...
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Inverse design of pore wall chemistry and topology through active ...
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Comprehensive Understanding of the Impact of Alkaline-Activated ...
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[90]
[PDF] 1 Inverse design of pore wall chemistry and topology through active ...
37 To assess the effect of roughness independent of chemistry, we simulate. 231. “fully hydrophobic” pores with only methyl and ethyl functional groups, as ...
[91]
[PDF] Pore Chemistry of Metal–Organic Frameworks - Omar Yaghi
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[92]
Pore - Name Meaning and Pronunciation - Ask Oracle
Origin: The name Pore has Georgian origins, specifically from the Signagi Municipality region. Usage: Pore is considered a unisex name, meaning it can be ...
[93]
Who are the Georgian national heroes abroad? - GeorgianJournal
May 30, 2019 · Pore Mosulishvili (1916-1944) was a Soviet soldier originated from Georgia. In 1939 the soldier was recruited in the Red Army. When the Germans ...<|separator|>
[94]
How Soviet soldiers became heroes of Italy - Russia Beyond
Dec 30, 2021 · For his self-sacrifice, which ultimately saved all his comrades' lives, Pore Mosulishvili was posthumously awarded the Gold Medal of Military ...
[95]
Pore Mosulishvili House Museum - GeorgianMuseums.ge
The museum houses Pore Mosulishvili's memorial items, medals, orders, albums, ethnographic items, photos, documents and more.
[96]
Pore Surname Origin, Meaning & Last Name History - Forebears
The last name Pore (Georgian: ფორე, Hindi: पोरे, Marathi: पोरे) is found most frequently in India. It may be found as: Poré or Póré. For other potential spellings ...
[97]
PORE Surname in India - iMeUsWe
State-wise distribution of people with this surname. from iMeUsWe Database. Uttar Pradesh. 6,043. Maharashtra. 2,823. Madhya ...
[98]
Pore Surname Meaning & Pore Family History at Ancestry.com®
The Pore family name was found in the USA, the UK, Canada, and Scotland between 1840 and 1920. The most Pore families were found in USA in 1880. In 1840 there ...Missing: distribution | Show results with:distribution
[99]
Pore Surname/Last Name: Meaning, Origin, Family History 2024
Pore ranks #30339 in the US. 57.07% White in US. Altered form of German Bohr. English (Sussex and Kent): variant of Power. In some cases possibly also.Missing: distribution | Show results with:distribution
[100]
Ryan Pore | MLSsoccer.com
Appeared in 29 games (28 starts), log¬ging 2,475 minutes and 84 shots … Scored six goals in the first four games of the season and was voted the USSF D-2 Pro ...
[101]
Ryan Pore - Head Coach - Men's Soccer Coaches - Kansas City Roos
Pore enters his fifth year at the helm for Kansas City Men's Soccer in 2024. In four seasons as the Roos' head coach, he has posted a 19-28-17 record.
[102]
The Roman Heritage of Poreč: Traces of the Past on the Adriatic Coast
Dec 30, 2024 · The history of Poreč stretches back over two millennia, with its foundations deeply rooted in the Roman period. The Romans arrived in the 2nd ...
[103]
Poreč – a city with a thousand-year history
Slavs settled in Istria, Poreč and its surrounding area in the 7th century. Poreč had a city-government as early as the 12th century and the first City Statute ...
[104]
Episcopal Complex of the Euphrasian Basilica in the Historic Centre ...
The group of religious monuments in Porec, where Christianity was established as early as the 4th century, constitutes the most complete surviving complex ...
[105]
Indian Place Names - IRFCA.org
-prolu Telugu 'village'. E.g. Bhattiprolu, Gollaprolu. -pur, -puri, -pura, -puram, -pore From Sanskrit, a town (walled city -- may also mean a city with a ...
[106]
Largest “pur” suffix cities of India and beyond: UPDATE #2 | Panethos
Dec 18, 2019 · The following list identifies the world's largest cities containing the suffix of “pur” along with two variations, “pura” and “pore.”
[107]
Boyagua — Pore | Colombia Google Satellite Maps - Maplandia.com
Pore and neighbouring regions · Paz de Ariporo · Tamara · Nunchia · San Luis de Palenque · Trinidad ...