reversed-phase is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Routine quality control uses system suitability, blank injections, check standards, and control samples to detect drift or contamination. System suitability criteria may specify minimum resolution, maximum tailing factor, and a permitted range for repeated injections. Blank injections reveal carryover or solvent contamination, while check standards confirm calibration accuracy over a batch. Control samples with known analyte levels can show whether results remain within statistical limits. When a control result falls outside limits, the analyst investigates the cause and may invalidate affected results before repeating the batch.
Documentation and traceability are central to regulated HPLC testing. Records typically include instrument logs, column history, mobile-phase preparation, sample preparation, injection sequences, raw chromatograms, and audit trails. Electronic systems may require user access controls, time-stamped changes, and backup procedures. Training records show that analysts are qualified for assigned methods. Audits and inspections check whether written procedures match actual practice and whether deviations are documented. These controls support reproducibility and allow results to be reconstructed if questions arise later.
Method validation establishes that an HPLC procedure is suitable for its intended purpose. Typical parameters include accuracy, precision, specificity, linearity, range, limit of detection, limit of quantitation, robustness, and solution stability. Accuracy reflects closeness to a reference value, while precision reflects agreement among repeated measurements. Specificity shows whether the method can measure the analyte without interference from matrix components. Validation is documented through protocols and reports, and the required extent depends on the method's use and regulatory context.
Developing an HPLC test begins with defining the analytes, matrix, and required reporting limits. Chemists select a separation mode, column chemistry, mobile phase composition, flow rate, and detection wavelength or mass transition. Experiments then adjust these variables to achieve adequate retention, resolution, and peak shape. System suitability tests confirm that the instrument and method perform consistently before sample analysis. Without suitable resolution, quantitative results may be unreliable. Preliminary runs often use scouting gradients to locate retention windows.
Validation establishes that a method is suitable for its intended purpose. Typical parameters include accuracy, precision, specificity, linearity, range, limit of detection, limit of quantification, robustness, and stability of standards and samples. Acceptance criteria are defined in advance, and results are documented in a validation report. Regulatory guidance for pharmaceuticals, foods, and environmental testing differs, so the applicable framework must be identified. Ongoing verification uses control samples and trend charts after validation. Method transfer to another laboratory may require partial revalidation.
Routine quality control includes blanks, duplicates, spiked samples, and certified reference materials. Calibration curves are prepared with standards at several concentrations, and the detector response is checked for linearity. Carryover, column aging, mobile phase evaporation, and temperature drift can shift retention times or peak areas. Maintenance such as replacing seals, filters, and columns helps prevent failures. Records of injections, integration, and deviations support traceability. Audits may request raw data and instrument logs for each batch.
| Property | Value | Notes |
|---|---|---|
| Accuracy | Recovery near 100% | Depends on acceptance criteria and matrix |
| Precision | Relative standard deviation | Often at or below 2% for replicate injections |
| Limit of detection | Signal-to-noise ratio 3:1 | Approximate and method-specific |
| Limit of quantitation | Signal-to-noise ratio 10:1 | Confirmed by precision and accuracy |
| Resolution | 1.5 or greater | Typical system suitability target |
Method validation establishes that an HPLC procedure is suitable for its intended use. Key parameters include accuracy, precision, specificity, linearity, range, limit of detection, limit of quantitation, and robustness. Accuracy measures agreement with a true or accepted value, while precision describes repeatability and intermediate precision. Specificity confirms that the method measures the analyte without interference from impurities, degradants, or excipients. Validation is documented in a protocol and report, and acceptance criteria are set before experiments begin. Regulatory guidance varies by region, but the general principles are widely harmonized.
System suitability testing is performed before and during analytical runs to confirm that the instrument and method are working as expected. Common checks include retention time, peak area, resolution between critical pairs, tailing factor, and theoretical plate count. Results are compared with predefined limits, and a failed check requires investigation before sample results are reported. Quality control samples at low, middle, and high concentrations are injected at intervals to monitor accuracy and precision. Blank injections detect carryover and contamination, while control charts track performance over time.
Data handling and documentation are central to HPLC quality control. Electronic systems should have audit trails that record changes to methods, sequences, and results. Integration parameters, such as peak baseline and threshold, can affect reported areas and must be defined in advance. Out-of-specification results trigger a structured investigation that may include reanalysis, instrument checks, and review of sample preparation. Regulatory inspections often examine raw data, audit trails, and training records to verify that reported results are traceable and reliable.
Several separation modes exist, including reversed-phase, normal-phase, ion-exchange, size-exclusion, and hydrophilic interaction liquid chromatography. Reversed-phase uses a nonpolar stationary phase with a polar mobile phase and is widely applied to small organic molecules. Gradient elution changes mobile phase composition during the run, while isocratic elution keeps it constant. Column chemistry, particle size, temperature, flow rate, and mobile phase pH all influence retention and resolution. Method development selects conditions that separate analytes from matrix components and from each other.
Detection commonly uses ultraviolet-visible absorbance, fluorescence, refractive index, or mass spectrometry. Ultraviolet detection depends on molecular chromophores that absorb light at specific wavelengths. Mass spectrometry provides mass information and sensitive quantification, often after electrospray ionization. Before sample batches, performance checks examine resolution, elution time repeatability, peak symmetry, and plate count. Matrix effects and co-elution remain recognized uncertainties; formal validation studies and orthogonal detection help address them. Detector choice depends on analyte properties and required sensitivity.
HPLC testing separates dissolved compounds by passing a liquid sample through a column packed with stationary phase. A pump delivers mobile phase at controlled flow, and the sample components interact differently with stationary and mobile phases. Compounds that spend more time in mobile phase elute earlier; those retained by stationary phase elute later. Detectors record elution as peaks, and peak area or height relates to amount. This mechanism underpins quantitative analysis of mixtures.
Most routine HPLC testing uses reversed-phase columns, where the stationary phase is nonpolar and the mobile phase is a polar mixture such as water with an organic solvent. Analytes partition between the two phases according to polarity, size, and charge. Gradients that change solvent composition over time can separate compounds with broad retention ranges. Isocratic conditions keep solvent composition constant and suit simpler mixtures. The choice of column chemistry, pH, and temperature affects selectivity and peak shape.
Detection in HPLC testing commonly relies on ultraviolet-visible absorbance, fluorescence, refractive index, or mass spectrometry. UV detection is widely used because many organic compounds absorb light, but it requires a chromophore. Mass spectrometry provides mass-based identification and high sensitivity for trace analytes. Each detector has trade-offs in selectivity, cost, and compatibility with mobile phases. Quantification typically uses calibration curves prepared from reference standards. Results are reported as concentration, purity, or presence above a limit.
Protactinium is a chemical element; it has symbol Pa and atomic number 91. It is a dense, radioactive, silvery-gray actinide metal which readily reacts with oxygen, water vapor, and inorganic acids. It forms various chemical compounds, in which protactinium is usually present in the oxidation state +5, but it can also assume +4 and even +3 or +2 states. Concentrations of protactinium in the Earth's crust are typically a few parts per trillion, but may reach up to a few parts per million in some uraninite ore deposits. Because of its scarcity, high radioactivity, and high toxicity, there are currently no uses for protactinium outside scientific research, and for this purpose, protactinium is mostly extracted from spent nuclear fuel. It is also the only highly radioactive mononuclidic element that is not also monoisotopic, occurring almost exclusively through the decay of Uranium-235. The element was first identified in 1913 by Kazimierz Fajans and Oswald Helmuth Göhring and named "brevium" because of the short half-life of the specific isotope studied, 234mPa. A more stable isotope of protactinium, 231Pa, was discovered in 1917/18 by Lise Meitner in collaboration with Otto Hahn, and they named the element protactinium. In 1949, the IUPAC chose the name "protactinium" and confirmed Hahn and Meitner as its discoverers. The new name meant "(nuclear) precursor of actinium," suggesting that actinium is a product of radioactive decay of protactinium.
Relugolix, sold under the brand names Orgovyx and Relumina among others, is a gonadotropin-releasing hormone antagonist (GnRH receptor antagonist) medication which is used in the treatment of prostate cancer, uterine fibroids and endometriosis. It is taken by mouth. Side effects of relugolix include menstrual abnormalities, hot flashes, excessive sweating, headache, and decreased bone mineral density. Relugolix is a GnRH antagonist, or an antagonist of the gonadotropin-releasing hormone receptor. Unlike most other GnRH modulators, but similarly to elagolix (brand name Orilissa), relugolix is a non-peptide, small-molecule compound and is orally active. It suppresses sex hormone levels to the postmenopausal or castrate range in both women and men.
=== Faïences décoratives de la Vieille Turquie (Decorative Faience in Ancient Turkey) === Raymond published Faïences décoratives de la Vieille Turquie (Decorative Faience in Ancient Turkey) through the Paris publisher Albert Morancé; a little book that reproduced some of the plates from L'Art Islamique en Orient and introduced new ones.
Sources: en.wikipedia.org
Leptin (from Greek λεπτός leptos, "thin" or "light" or "small"), also known as obese protein, is a protein hormone predominantly made by adipocytes (cells of adipose tissue). Its primary role is likely to regulate long-term energy balance. As one of the major signals of energy status, leptin levels influence appetite, satiety, and motivated behaviors oriented toward the maintenance of energy reserves (e.g., feeding, foraging behaviors). The amount of circulating leptin correlates with the amount of energy reserves, mainly triglycerides stored in adipose tissue. High leptin levels are interpreted by the brain that energy reserves are high, whereas low leptin levels indicate that energy reserves are low, in the process adapting the organism to starvation through a variety of metabolic, endocrine, neurobiochemical, and behavioral changes. Leptin is coded for by the LEP gene. Leptin receptors are expressed by a variety of brain and peripheral cell types. These include cell receptors in the arcuate and ventromedial nuclei, as well as other parts of the hypothalamus and dopaminergic neurons of the ventral tegmental area, consequently mediating feeding. Although regulation of fat stores is deemed to be the primary function of leptin, it also plays a role in other physiological processes, as evidenced by its many sites of synthesis other than fat cells, and the many cell types beyond hypothalamic cells that have leptin receptors. Many of these additional functions are yet to be fully defined.
Technology's central role in human life has drawn concerns and backlash. The backlash against technology is not a uniform movement and encompasses many heterogeneous ideologies. The earliest known revolt against technology was Luddism, a pushback against early automation in textile production. Automation had resulted in a need for fewer workers, a process known as technological unemployment. Between the 1970s and 1990s, American terrorist Ted Kaczynski carried out a series of bombings across America and published the Unabomber Manifesto denouncing technology's negative impacts on nature and human freedom. The essay resonated with a large part of the American public. It was partly inspired by Jacques Ellul's The Technological Society. Some subcultures, like the off-the-grid movement, advocate a withdrawal from technology and a return to nature. The ecovillage movement seeks to reestablish harmony between technology and nature.
== ISO 8000 – ISO 8999 == ISO 8000 Data quality ISO 8002:1986 Mechanical vibrations – Land vehicles – Method for reporting measured data ISO 8015:2011 Geometrical product specifications (GPS) – Fundamentals – Concepts, principles and rules ISO 8041:2005 Human response to vibration - Measuring instrumentation ISO 8041-1:2017 Part 1: General purpose vibration meters ISO 8042:1988 Shock and vibration measurements – Characteristics to be specified for seismic pick-ups ISO 8044:2015 Corrosion of metals and alloys – Basic terms and definitions ISO 8048:1984 Technical drawings – Construction drawings – Representation of views, sections and cuts ISO 8049:2016 Ferronickel shot - Sampling for analysis ISO 8050:1988 Ferronickel ingots or pieces - Sampling for analysis ISO 8062 Geometrical product specifications (GPS) - Dimensional and geometrical tolerances for moulded parts ISO 8062-1:2007 Part 1: Vocabulary ISO/TS 8062-2:2013 Part 2: Rules ISO 8062-3:2007 Part 3: General dimensional and geometrical tolerances and machining allowances for castings ISO 8062-4:2017 Part 4: General tolerances for castings using profile tolerancing in a general datum system ISO 8063 Information processing – Data interchange on 6,30 mm (0.25 in) wide magnetic tape cartridge using IMFM recording at 252 ftpmm (6 400 ftpi) ISO 8063-1:1986 Part 1: Mechanical, physical and magnetic properties ISO 8063-2:1986 Part 2: Track format and method of recording for data interchange in start/stop mode ISO 8064:1985 Information processing – Reels for 12,7 mm (0,5 in) wide magnetic tapes – Sizes 16, 18 and 22 ISO/IEC 8072:1996 Information technology – Open systems interconnection – Transport service definition ISO/IEC 8073:1997 Information technology – Open Systems Interconnection – Protocol for providing the connection-mode transport service ISO 8088:1994 Equipment for olive cultivation and olive oil production – Vocabulary ISO 8090:1990 Cycles – Terminology ISO 8107:1993 Nuclear power plants - Maintainability - Terminology ISO 8109:1990 Banking and related financial services – Securities – Format of Eurobonds ISO 8114:1990 Textile machinery and accessories – Spindles for ring-spinning and doubling machines – List of equivalent terms ISO 8116 Textile machinery and accessories – Beams for winding ISO 8116-1:1995 Part 1: General vocabulary ISO 8119 Textile machinery and accessories – Needles for knitting machines – Terminology ISO 8119-1:1989 Part 1: Latch-type needles ISO 8119-2:1989 Part 2: Bearded needles ISO 8119-3:1992 Part 3: Compound needles ISO/IEC 81346: Industrial systems, installations and equipment and industrial products – structuring principles and reference designations ISO 8147:1995 Shipbuilding and marine structures – Derrick rigs and component parts – Vocabulary ISO 8152:1984 Earth-moving machinery – Operation and maintenance – Training of mechanics ISO 8153 Aerospace fluid systems and components – Vocabulary ISO 8153-1:2009 Part 1: Hose assemblies ISO 8157:2015 Fertilizers and soil conditioners – Vocabulary ISO 8159:1987 Textiles – Morphology of fibres and yarns – Vocabulary ISO 8160:1987 Textiles – Textured filament yarns – Vocabulary ISO 8178 Reciprocating internal combustion engines - Exhaust emission measurement ISO 8180 Ductile iron pipelines – Polyethylene sleeving for site application ISO 8199:2005 Water quality – General guidance on the enumeration of micro-organisms by culture ISO/IEC 8208:2000 Information technology – Data communications – X.25 Packet Layer Protocol for Data Terminal Equipment ISO/IEC 8211:1994 Information technology - Specification for a data descriptive file for information interchange ISO 8217:2017 Petroleum products - Fuels (class F) - Specifications of marine fuels ISO 8229:1991 Operations and baths relating to dry-cleaning machines – Vocabulary ISO 8277:2013 Ships and marine technology – Pipework and machinery – Information transfer ISO 8297:1994 Acoustics – Determination of sound power levels of multisource industrial plants for evaluation of sound pressure levels in the environment – Engineering method ISO 8316:1987 Measurement of liquid flow in closed conduits – Method by collection of the liquid in a volumetric tank ISO 8317:2015 Child-resistant packaging - Requirements and testing procedures for reclosable packages ISO 8319 Orthopaedic instruments – Drive connections ISO 8319-1:1996 Part 1: Keys for use with screws with hexagon socket heads ISO 8319-2:1986 Part 2: Screwdrivers for single slot head screws, screws with cruciate slot and cross-recessed head screws ISO/IEC 8326:1996 Information technology – Open Systems Interconnection – Session service definition ISO/IEC 8327 Information technology – Open Systems Interconnection – Connection-oriented Session protocol ISO/IEC 8327-1:1996 Protocol specification ISO/IEC 8327-2:1996 Protocol Implementation Conformance Statement (PICS) proforma ISO 8330:2014 Rubber and plastics hoses and hose assemblies - Vocabulary ISO 8333:1985 Liquid flow measurement in open channels by weirs and flumes – V-shaped broad-crested weirs ISO 8343:1985 Ferronickel - Determination of silicon content - Gravimetric method ISO/IEC 8348:2002 Information technology – Open Systems Interconnection – Network service definition ISO 8362 Injection containers and accessories ISO 8362-1:2009 Part 1: Injection vials made of glass tubing ISO 8362-2:2015 Part 2: Closures for injection vials ISO 8362-3:2001 Part 3: Aluminium caps for injection vials ISO 8362-4:2011 Part 4: Injection vials made of moulded glass ISO 8362-5:2016 Part 5: Freeze drying closures for injection vials ISO 8362-6:2010 Part 6: Caps made of aluminium-plastics combinations for injection vials ISO 8362-7:2006 Part 7: Injection caps made of aluminium-plastics combinations without overlapping plastics part ISO/TR 8363:1997 Measurement of liquid flow in open channels — General guidelines for selection of method [Withdrawn: replaced by ISO 18365] ISO 8368:1999 Hydrometric determinations – Flow measurements in open channels using structures – Guidelines for selection of structure ISO 8373:2012 Manipulating industrial robots – Vocabulary ISO 8378 Information processing – Data interchange on 130 mm (5.25 in) flexible disk cartridges using modified frequency modulation recording at 7 958 ftprad, 3,8 tpmm (96 tpi), on both sides ISO 8378-1:1986 Part 1: Dimensional, physical and magnetic characteristics ISO 8378-2:1986 Part 2: Track format A ISO 8378-3:1986 Part 3: Track format B ISO 8384:2000 Ships and marine technology – Dredgers – Vocabulary ISO 8388:1998 Knitted fabrics – Types – Vocabulary ISO 8421 Fire protection - Vocabulary ISO 8421-1:1987 Part 1: General terms and phenomena of fire ISO 8421-2:1987 Part 2: Structural fire protection ISO 8421-6:1987 Part 6: Evacuation and means of escape ISO 8421-7:1987 Part 7: Explosion detection and suppression means ISO 8422:2006 Sequential sampling plans for inspection by attributes ISO 8423:2008 Sequential sampling plans for inspection by variables for percent nonconforming (known standard deviation) ISO 8429:1986 Optics and optical instruments – Ophthalmology – Graduated dial scale ISO 8439:1990 Forms design - Basic layout ISO 8440:1986 Location of codes in trade documents ISO/IEC 8441 Information technology – High density digital recording (HDDR) ISO/IEC 8441-1:1991 Part 1: Unrecorded magnetic tape for (HDDR) applications ISO/IEC 8441-2:1991 Part 2: Guide for interchange practice ISO 8459:2009 Information and documentation - Bibliographic data element directory for use in data exchange and enquiry ISO 8462 Information processing – Data interchange on 6,30 mm (0.25 in) magnetic tape cartridge using GCR recording at 394 ftpmm (10 000 ftpi), 39 cpmm (1 000 cpi) ISO 8462-1:1986 Part 1: Mechanical, physical and magnetic properties ISO 8462-2:1986 Part 2: Streaming mode ISO/IEC 8473 Information technology – Protocol for providing the connectionless-mode network service ISO/IEC 8473-1:1998 Protocol specification ISO/IEC 8473-2:1996 Part 2: Provision of the underlying service by an ISO/IEC 8802 subnetwork ISO/IEC 8473-3:1995 Provision of the underlying service by an X.25 subnetwork ISO/IEC 8473-4:1995 Provision of the underlying service by a subnetwork that provides the OSI data link service ISO/IEC 8473-5:1997 Provision of the underlying service by ISDN circuit-switched B-channels ISO/IEC 8480:1995 Information technology – Telecommunications and information exchange between systems – DTE/DCE interface back-up control operation using ITU-T Recommendation V.24 interchange circuits ISO/IEC 8481:1996 Information technology – Telecommunications and information exchange between systems – DTE to DTE direct connections ISO/IEC 8482:1993 Information technology – Telecommunications and information exchange between systems – Twisted pair multipoint interconnections ISO/IEC 8484:2014 Information technology – Magnetic stripes on savingsbooks ISO 8485:1989 Programming languages - APL ISO 8498:1990 Woven fabrics – Description of defects – Vocabulary ISO 8499:2003 Knitted fabrics – Description of defects – Vocabulary ISO 8501 Preparation of steel substrates before application of paints and related products – Visual assessment of surface cleanliness ISO 8501-1:2007 Part 1: Rust grades and preparation grades of uncoated steel substrates and of steel substrates after overall removal of previous coatings ISO 8501-2:1994 Part 2: Preparation grades of previously coated steel substrates after localized removal of previous coatings ISO 8501-3:2006 Part 3: Preparation grades of welds, edges and other areas with surface imperfections ISO 8501-4:2006 Part 4: Initial surface conditions, preparation grades and flash rust grades in connection with high-pressure water jetting ISO 8502 Preparation of steel substrates before application of paints and related products - Tests for the assessment of surface cleanliness ISO 8502-2:2017 Part 2: Laboratory determination of chloride on cleaned surfaces ISO 8502-3:2017 Part 3: Assessment of dust on steel surfaces prepared for painting (pressure-sensitive tape method) ISO 8502-4:2017 Part 4: Guidance on the estimation of the probability of condensation prior to paint application ISO 8502-5:1998 Part 5: Measurement of chloride on steel surfaces prepared for painting (ion detection tube method ISO 8502-6:2006 Part 6: Extraction of soluble contaminants for analysis - The Bresle method ISO 8502-9:1998 Part 9: Field method for the conductometric determination of water-soluble salts ISO 8502-11:2006 Part 11: Field method for the turbidimetric determination of water-soluble sulfate ISO 8503 Preparation of steel substrates before application of paints and related products - Surface roughness characteristics of blast-cleaned steel substrates ISO 8503-1:2012 Part 1: Specifications and definitions for ISO surface profile comparators for the assessment of abrasive blast-cleaned surfaces ISO 8503-2:2012 Part 2: Method for the grading of surface profile of abrasive blast-cleaned steel - Comparator procedure ISO 8503-3:2012 Part 3: Method for the calibration of ISO surface profile comparators and for the determination of surface profile - Focusing microscope procedure ISO 8503-4:2012 Part 4: Method for the calibration of ISO surface profile comparators and for the determination of surface profile - Stylus instrument procedure ISO 8503-5:2017 Part 5: Replica tape method for the determination of the surface profile ISO 8504 Preparation of steel substrates before application of paints and related products - Surface preparation methods ISO 8504-1:2000 Part 1: General principles ISO 8504-2:2000 Part 2: Abrasive blast-cleaning ISO 8504-3:1993 Part 3: Hand- and power-tool cleaning ISO 8506:2024 Information technology — Automatic identification and data capture technology — AIDC application in industrial construction ISO 8512 Surface plates ISO 8512-1:1990 Part 1: Cast iron ISO 8512-2:1990 Part 2: Granite ISO/TR 8517:1988 Rubber- or plastics-covered rollers – Glossary ISO 8525:2008 Airborne noise emitted by machine tools – Operating conditions for metal-cutting machines ISO 8528 Reciprocating internal combustion engine driven alternating current generating sets ISO 8528-1:2005 Part 1: Application, ratings and performance ISO 8528-2:2005 Part 2: Engines ISO 8528-3:2005 Part 3: Alternating current generators for generating sets ISO 8528-4:2005 Part 4: Controlgear and switchgear ISO 8528-5:2013 Part 5: Generating sets ISO 8528-6:2005 Part 6: Test methods ISO 8528-7:2017 Part 7: Technical declarations for specification and design ISO 8528-8:2016 Part 8: Requirements and tests for low-power generating sets ISO 8528-9:2017 Part 9: Measurement and evaluation of mechanical vibrations ISO 8528-10:1998 Part 10: Measurement of airborne noise by the enveloping surface method ISO 8528-12:1997 Part 12: Emergency power supply to safety services ISO 8528-13:2016 Part 13: Safety ISO 8529 Reference neutron radiations ISO 8529-1:2001 Part 1: Characteristics and methods of production ISO 8529-2:2000 Part 2: Calibration fundamentals of radiation protection devices related to the basic quantities characterizing the radiation field ISO 8529-3:1998 Part 3: Calibration of area and personal dosimeters and determination of response as a function of energy and angle of incidence ISO 8532:1995 Securities – Format for transmission of certificate numbers ISO 8536 Infusion equipment for medical use ISO 8536-1:2011 Part 1: Infusion glass bottles ISO 8536-2:2010 Part 2: Closures for infusion bottles ISO 8536-3:2009 Part 3: Aluminium caps for infusion bottles ISO 8536-4:2010 Part 4: Infusion sets for single use, gravity feed ISO 8536-5:2004 Part 5: Burette infusion sets for single use, gravity feed ISO 8536-6:2016 Part 6: Freeze drying closures for infusion bottles ISO 8536-7:2009 Part 7: Caps made of aluminium-plastics combinations for infusion bottles ISO 8536-8:2015 Part 8: Infusion sets for single use with pressure infusion apparatus ISO 8536-9:2015 Part 9: Fluid lines for single use with pressure infusion equipment ISO 8536-10:2015 Part 10: Accessories for fluid lines for single use with pressure infusion equipment ISO 8536-11:2015 Part 11: Infusion filters for single use with pressure infusion equipment ISO 8536-12:2007 Part 12: Check valves ISO 8536-13:2016 Part 13: Graduated flow regulators for single use with fluid contact ISO 8536-14:2016 Part 14: Clamps and flow regulators for transfusion and infusion equipment without fluid contact ISO 8537:2016 Sterile single-use syringes, with or without needle, for insulin ISO 8540:1993 Open front mechanical power presses - Vocabulary ISO 8548 Prosthetics and orthotics – Limb deficiencies ISO 8548-1:1989 Part 1: Method of describing limb deficiencies present at birth ISO 8548-2:1993 Part 2: Method of describing lower limb amputation stumps ISO 8548-3:1993 Part 3: Method of describing upper limb amputation stumps ISO 8548-4:1998 Part 4: Description of causal conditions leading to amputation ISO 8548-5:2003 Part 5: Description of the clinical condition of the person who has had an amputation ISO 8549 Prosthetics and orthotics - Vocabulary ISO 8549-1:1989 Part 1: General terms for external limb prostheses and external orthoses ISO 8549-2:1989 Part 2: Terms relating to external limb prostheses and wearers of these prostheses ISO 8549-3:1989 Part 3: Terms relating to external orthoses ISO 8549-4:2014 Part 4: Terms relating to limb amputation ISO/TR 8550 Guidance on the selection and usage of acceptance sampling systems for inspection of discrete items in lots ISO/TR 8550-1:2007 Part 1: Acceptance sampling ISO/TR 8550-2:2007 Part 2: Sampling by attributes ISO/TR 8550-3:2007 Part 3: Sampling by variables ISO 8551:2003 Prosthetics and orthotics – Functional deficiencies – Description of the person to be treated with an orthosis, clinical objectives of treatment, and functional requirements of the orthosis ISO 8552:2004 Milk – Estimation of psychrotrophic microorganisms – Colony-count technique at 21 degrees C (Rapid method) ISO 8553:2004 Milk – Enumeration of microorganisms – Plate-loop technique at 30 degrees C ISO 8559:1989 Garment construction and anthropometric surveys – Body dimensions [Withdrawn: replaced by ISO 8559-1:2017] ISO 8559 Size designation of clothes ISO 8559-1:2017 Part 1: Anthropometric definitions for body measurement ISO 8559-2:2017 Part 2: Primary and secondary dimension indicators ISO 8560:1986 Technical drawings – Construction drawings – Representation of modular sizes, lines and grids ISO 8568:2007 Mechanical shock – Testing machines – Characteristics and performance ISO 8571 Information processing systems - Open Systems Interconnection - File Transfer, Access and Management ISO 8571-1:1988 Part 1: General introduction ISO 8571-2:1988 Part 2: Virtual Filestore Definition ISO 8571-3:1988 Part 3: File Service Definition ISO 8571-4:1988 Part 4: File Protocol Specification ISO/IEC 8571-5:1990 Part 5: Protocol Implementation Conformance Statement Proforma ISO 8573 Compressed air ISO 8573-1:2010 Contaminants and purity classes ISO 8573-2:2007 Test methods for oil aerosol content ISO 8573-3:1999 Test methods for measurement of humidity ISO 8573-4:2001 Test methods for solid particle content ISO 8573-5:2001 Test methods for oil vapour and organic solvent content ISO 8573-6:2003 Test methods for gaseous contaminant content ISO 8573-7:2003 Test method for viable microbiological contaminant content ISO 8573-8:2004 Test methods for solid particle content by mass concentration ISO 8573-9:2004 Test methods for liquid water content ISO 8579 Acceptance code for gear units ISO 8579-1:2002 Part 1: Test code for airborne sound ISO 8583 Financial transaction card originated messages – Interchange message specifications ISO 8586:2012 Sensory analysis – General guidelines for the selection, training and monitoring of selected assessors and expert sensory assessors ISO 8596:2009 Ophthalmic optics – Visual acuity testing – Standard optotype and its presentation ISO 8598 Optics and optical instruments – Focimeters ISO 8598-1:2014 Part 1: General purpose instruments ISO 8600 Endoscopes – Medical endoscopes and endotherapy devices ISO 8600-1:2015 Part 1: General requirements ISO 8600-2:2015 Part 2: Particular requirements for rigid bronchoscopes ISO 8600-3:1997 Part 3: Determination of field of view and direction of view of endoscopes with optics ISO 8600-4:2014 Part 4: Determination of maximum width of insertion portion ISO 8600-5:2005 Part 5: Determination of optical resolution of rigid endoscopes with optics ISO 8600-6:2005 Part 6: Vocabulary ISO 8600-7:2012 Part 7: Basic requirements for medical endoscopes of water-resistant type ISO 8601:2019 Data elements and interchange formats – Information interchange – Representation of dates and times ISO/IEC 8602:1995 Information technology – Protocol for providing the OSI connectionless-mode transport service ISO 8604:1988 Plastics – Prepregs – Definitions of terms and symbols for designations ISO 8608:2016 Mechanical vibration – Road surface profiles – Reporting of measured data ISO 8612:2009 Ophthalmic instruments – Tonometers ISO/IEC 8613 Information technology – Open Document Architecture (ODA) and interchange format ISO 8614:1997 Ski bindings – Vocabulary ISO 8615:1991 Implants for surgery – Fixation devices for use in the ends of the femur in adults ISO 8624:2011 Ophthalmic optics – Spectacle frames – Measuring system and terminology ISO 8625 Aerospace – Fluid systems – Vocabulary ISO 8625-1:1993 Part 1: General terms and definitions related to pressure ISO 8625-2:1991 Part 2: General terms and definitions relating to flow ISO 8625-3:1991 Part 3: General terms and definitions relating to temperature ISO 8625-4:2011 Part 4: General terms and definitions relating to control/actuation systems ISO 8626:1989 Servo-hydraulic test equipment for generating vibration – Method of describing characteristics ISO 8630 Information processing – Data interchange on 130 mm (5.25 in) flexible disk cartridges using modified frequency modulation recording at 13 262 ftprad, on 80 tracks on each side ISO 8630-1:1987 Part 1: Dimensional, physical and magnetic characteristics ISO 8630-2:1987 Part 2: Track format A for 77 tracks ISO 8630-3:1987 Part 3: Track format B for 80 tracks ISO/IEC 8631:1989 Information technology - Program constructs and conventions for their representation ISO/IEC 8632 Information technology – Computer graphics – Metafile for the storage and transfer of picture description information ISO/IEC 8632-1:1999 Part 1: Functional specification ISO/IEC 8632-2:1992 Part 2: Character encoding [withdrawn 2001-06-21] ISO/IEC 8632-3:1999 Part 3: Binary encoding ISO/IEC 8632-4:1999 Part 4: Clear text encoding ISO 8637:2010 Cardiovascular implants and extracorporeal systems – Haemodialysers, haemodiafilters, haemofilters and haemoconcentrators ISO 8638:2010 Cardiovascular implants and extracorporeal systems – Extracorporeal blood circuit for haemodialysers, haemodiafilters and haemofilters ISO 8640 Textile machinery and accessories – Flat warp knitting machines ISO 8640-1:2004 Part 1: Vocabulary of basic structure and knitting elements ISO 8640-2:2004 Part 2: Vocabulary of warp let-off, fabric take-up and batching ISO 8640-3:2002 Part 3: Vocabulary of patterning devices ISO 8640-4:1996 Part 4: Stitch bonding machines and stitch bonding devices ISO 8648:1988 Information processing systems – Open Systems Interconnection – Internal organization of the Network Layer ISO/IEC 8650 Information technology – Open Systems Interconnection – Protocol specification for the Association Control Service Element ISO/IEC 8650-2:1997 Protocol Implementation Conformance Statement (PICS) proforma ISO 8651 Information technology – Computer graphics – Graphical Kernel System (GKS) language bindings ISO 8651-1:1988 Part 1: FORTRAN ISO 8651-2:1988 Part 2: Pascal ISO 8651-3:1988 Part 3: Ada ISO/IEC 8651-4:1995 Part 4: C ISO/IEC 8652:2012 Information technology – Programming languages – Ada ISO 8653:1986 Jewellery – Ring-sizes – Definition, measurement and designation ISO 8655 Piston-operated volumetric apparatus ISO 8655-1:2002 Part 1: Terminology, general requirements and user recommendations ISO 8655-2:2002 Part 2: Piston pipettes ISO 8655-3:2002 Part 3: Piston burettes ISO 8655-4:2002 Part 4: Dilutors ISO 8655-5:2002 Part 5: Dispensers ISO 8655-6:2002 Part 6: Gravimetric methods for the determination of measurement error ISO 8655-7:2005 Part 7: Non-gravimetric methods for the assessment of equipment performance ISO 8669 Urine collection bags ISO 8669-1:1988 Part 1: Vocabulary ISO 8670 Ostomy collection bags ISO 8670-1:1988 Part 1: Vocabulary ISO 8691 Petroleum products – Low levels of vanadium in liquid fuels – Determination by flameless atomic absorption spectrometry after ashing ISO 8695:2010 Tools for pressing - Punches - Nomenclature and terminology ISO/TR 8713:2012 Electrically propelled road vehicles – Vocabulary ISO 8769:2016 Reference sources - Calibration of surface contamination monitors - Alpha-, beta- and photon emitters ISO 8777:1993 Information and documentation - Commands for interactive text searching ISO 8784 Pulp, paper and board – Microbiological examination ISO 8784-1:2014 Part 1: Enumeration of bacteria and bacterial spores based on disintegration ISO 8785:1998 Geometrical Product Specification (GPS) - Surface imperfections - Terms, definitions and parameters ISO 8790:1987 Information processing systems - Computer system configuration diagram symbols and conventions ISO/IEC 8802 Information technology – Telecommunications and information exchange between systems – Local and metropolitan area networks – Specific requirements ISO/IEC/IEEE 8802-A:2015 Part A: Overview and architecture ISO/IEC TR 8802-1:2001 Part 1: Overview of Local Area Network Standards ISO/IEC/IEEE 8802-1Q:2016 Part 1Q: Bridges and bridged networks ISO/IEC/IEEE 8802-1X:2013 Part 1X: Port-based network access control ISO/IEC/IEEE 8802-1AB:2017 Part 1AB: Station and media access control connectivity discovery ISO/IEC/IEEE 8802-1AE:2013 Part 1AE: Media access control (MAC) security ISO/IEC/IEEE 8802-1AR:2014 Part 1AR: Secure device identity ISO/IEC/IEEE 8802-1AS:2014 Part 1AS: Timing and synchronization for time-sensitive applications in bridged local area networks ISO/IEC/IEEE 8802-1AX:2016 Part 1AX: Link aggregation ISO/IEC/IEEE 8802-1BA:2016 Part 1BA: Audio video bridging (AVB) systems ISO/IEC/IEEE 8802-1BR:2016 Part 1BR: Virtual bridged local area networks – Bridge port extension ISO/IEC 8802-2:1998 Part 2: Logical link control ISO/IEC/IEEE 8802-3:2017 Part 3: Standard for Ethernet ISO/IEC/IEEE 8802-3-1:2015 Part 3-1: Standard for management information base (MIB) – Definitions for Ethernet ISO/IEC 8802-5:1998 Part 5: Token Ring access method and physical layer specifications ISO/IEC/IEEE 8802-11:2012 Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications ISO/IEC/IEEE 8802-15-4:2010 Part 15-4: Wireless medium access control (MAC) and physical layer (PHY) specifications for low-rate wireless personal area networks (WPANs) ISO/IEC/IEEE 8802-22:2015 Part 22: Cognitive Wireless RAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications: Policies and Procedures for Operation in the TV Bands ISO 8805 Information processing systems – Computer graphics – Graphical Kernel System for Three Dimensions (GKS-3D) functional description ISO/IEC 8806 Information technology – Computer graphics – Graphical Kernel System for Three Dimensions (GKS-3D) language bindings ISO/IEC 8806-4 Part 4: C ISO 8807:1989 Information processing systems – Open Systems Interconnection – LOTOS – A formal description technique based on the temporal ordering of observational behaviour ISO 8811:2000 Earth-moving machinery – Rollers and compactors – Terminology and commercial specifications ISO 8812:2016 Earth-moving machinery – Backhoe loaders – Terminology and commercial specifications ISO 8815:1994 Aircraft – Electrical cables and cable harnesses – Vocabulary ISO/IEC 8822:1994 Information technology – Open Systems Interconnection – Presentation service definition ISO/IEC 8823 Information technology – Open Systems Interconnection – Connection-oriented presentation protocol ISO/IEC 8823-1:1994 Protocol specification ISO/IEC 8823-2:1997 Protocol Implementation Conformance Statement (PICS) proforma ISO/IEC 8824 Information technology – Abstract Syntax Notation One (ASN.1) ISO/IEC 8824-1:2015 Specification of basic notation ISO/IEC 8824-2:2015 Information object specification ISO/IEC 8824-3:2015 Constraint specification ISO/IEC 8824-4:2015 Parameterization of ASN.1 specifications ISO/IEC 8825 Information technology – ASN.1 encoding rules ISO/IEC 8825-1:2015 Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER) ISO/IEC 8825-2:2015 Specification of Packed Encoding Rules (PER) ISO/IEC 8825-3:2015 Specification of Encoding Control Notation (ECN) ISO/IEC 8825-4:2015 XML Encoding Rules (XER) ISO/IEC 8825-5:2015 Mapping W3C XML schema definitions into ASN.1 ISO/IEC 8825-6:2015 Registration and application of PER encoding instructions ISO/IEC 8825-7:2015 Part 7: Specification of Octet Encoding Rules (OER) ISO 8826 Technical drawings – Rolling bearings ISO 8826-1:1989 Part 1: General simplified representation ISO 8826-2:1994 Part 2: Detailed simplified representation ISO 8827:1988 Implants for surgery – Staples with parallel legs for orthopaedic use – General requirements ISO 8828:2014 Implants for surgery – Guidance on care and handling of orthopaedic implants ISO 8835 Inhalational anaesthesia systems ISO 8835-7:2011 Part 7: Anaesthetic systems for use in areas with limited logistical supplies of electricity and anaesthetic gases ISO 8836:2014 Suction catheters for use in the respiratory tract ISO 8843:2005 Aircraft – Crimp-removable contacts for electrical connectors – Identification system ISO 8855:2011 Road vehicles – Vehicle dynamics and road-holding ability – Vocabulary ISO/IEC 8859 Information technology – 8-bit single-byte coded graphic character sets ISO/IEC 8859-1:1998 Part 1: Latin alphabet No. 1 ISO/IEC 8859-2:1999 Part 2: Latin alphabet No. 2 ISO/IEC 8859-3:1999 Part 3: Latin alphabet No. 3 ISO/IEC 8859-4:1998 Part 4: Latin alphabet No. 4 ISO/IEC 8859-5:1999 Part 5: Latin/Cyrillic alphabet ISO/IEC 8859-6:1999 Part 6: Latin/Arabic alphabet ISO/IEC 8859-7:2003 Part 7: Latin/Greek alphabet ISO/IEC 8859-8:1999 Part 8: Latin/Hebrew alphabet ISO/IEC 8859-9:1999 Part 9: Latin alphabet No. 5 ISO/IEC 8859-10:1998 Part 10: Latin alphabet No. 6 ISO/IEC 8859-11:2001 Part 11: Latin/Thai alphabet ISO/IEC 8859-13:1998 Part 13: Latin alphabet No. 7 ISO/IEC 8859-14:1998 Part 14: Latin alphabet No. 8 (Celtic) ISO/IEC 8859-15:1999 Part 15: Latin alphabet No. 9 ISO/IEC 8859-16:2001 Part 16: Latin alphabet No. 10 ISO 8860 Information processing – Data interchange on 90 mm (3.5 in) flexible disk cartridges using modified frequency modulation recording at 7 958 ftprad on 80 tracks on each side ISO 8860-1:1987 Part 1: Dimensional, physical and magnetic characteristics ISO 8860-2:1987 Part 2: Track format ISO 8871 Elastomeric parts for parenterals and for devices for pharmaceutical use ISO 8871-1:2003 Part 1: Extractables in aqueous autoclavates ISO 8871-2:2003 Part 2: Identification and characterization ISO 8871-3:2003 Part 3: Determination of released-particle count ISO 8871-4:2006 Part 4: Biological requirements and test methods ISO 8871-5:2016 Part 5: Functional requirements and testing ISO 8872:2003 Aluminium caps for transfusion, infusion and injection bottles – General requirements and test methods ISO/IEC 8877:1992 Information technology – Telecommunications and information exchange between systems – Interface connector and contact assignments for ISDN Basic Access Interface located at reference points S and T ISO/IEC 8878:1992 Information technology – Telecommunications and information exchange between systems – Use of X.25 to provide the OSI Connection-mode Network Service ISO 8879:1986 Information processing – Text and office systems – Standard Generalized Markup Language (SGML) ISO/IEC 8880 Information technology — Telecommunications and information exchange between systems — Protocol combinations to provide and support the OSI Network Service ISO/IEC 8880-1:1990 Part 1: General principles [Withdrawn: replaced by ISO/IEC TR 13532:1995, now withdrawn without replacement] ISO/IEC 8880-2:1992 Part 2: Provision and support of the connection-mode Network Service [Withdrawn: replaced by ISO/IEC TR 13532:1995, now withdrawn without replacement] ISO/IEC 8880-3:1990 Part 3: Provision and support of the connectionless-mode Network Service [Withdrawn: replaced by ISO/IEC TR 13532:1995, now withdrawn without replacement] ISO/IEC 8881:1989 Information processing systems – Data communications – Use of the X.25 packet level protocol in local area networks ISO/IEC 8882 Information technology – Telecommunications and information exchange between systems – X.25 DTE conformance testing ISO/IEC 8882-1:1996 Part 1: General principles ISO/IEC 8882-2:2000 Part 2: Data link layer conformance test suite ISO/IEC 8882-3:2000 Part 3: Packet layer conformance test suite ISO 8884:1989 Information processing — Text and office systems — Keyboards for multiple Latin-alphabet languages — Layout and operation [Withdrawn: replaced with ISO 9995-(1,7)] ISO 8885:1987 Information processing systems — Data communication — High-level data link control procedures — General purpose XID frame information field content and format [Withdrawn without replacement] ISO/IEC 8886:1996 Information technology – Open Systems Interconnection – Data link service definition ISO 8887 Technical product documentation – Design for manufacturing, assembling, disassembling and end-of-life processing ISO 8887-1:2017 Part 1: General concepts and requirements ISO 8891:1998 Dental casting alloys with noble metal content of at least 25 % but less than 75 % [Withdrawn: replaced with ISO 22674] ISO 8909 Forage harvesters ISO 8909-1:1994 Part 1: Vocabulary ISO 8910:1993 Machinery and equipment for working the soil – Mouldboard plough working elements – Vocabulary ISO 8927:1991 Earth-moving machinery – Machine availability – Vocabulary ISO 8930:1987 General principles on reliability for structures – List of equivalent terms ISO 8936:2017 Awnings for leisure accommodation vehicles - Requirements and test methods ISO 8954 Ferroalloys - Vocabulary ISO 8954-1:1990 Part 1: Materials ISO 8954-2:1990 Part 2: Sampling and sample preparation ISO 8954-3:1990 Part 3: Sieve analysis ISO 8957:1996 Information and documentation - Hebrew alphabet coded character sets for bibliographic information interchange ISO 8965:2013 Logging industry – Technology – Terms and definitions ISO 8979:2004 Pliers and nippers for electronics - Nomenclature ISO 8980 Ophthalmic optics – Uncut finished spectacle lenses ISO 8980-1:2017 Part 1: Specifications for single-vision and multifocal lenses ISO 8980-2:2017 Part 2: Specifications for power-variation lenses ISO 8980-3:2013 Part 3: Transmittance specifications and test methods ISO 8980-4:2006 Part 4: Specifications and test methods for anti-reflective coatings ISO 8980-5:2005 Part 5: Minimum requirements for spectacle lens surfaces claimed to be abrasion-resistant ISO 8999:2001 Reciprocating internal combustion engines - Graphical symbols
Sources: en.wikipedia.org
== Partnerships == In 2013 US Fleet Tracking announced the formation of a strategic partnership with AgTrax Technologies, developers of accounting software programs for agri-businesses. The partnership resulted in the integration of AgTrax’s software with US Fleet Tracking’s TotalView system to create an enhanced GPS tracking system that enables real-time monitoring of mobile agricultural equipment. In 2016 US Fleet Tracking established a partnership with Gorilla Safety, a Houston-based company specializing in software for the transportation sector, to create a fully integrated system that combines live GPS tracking with electronic logging features compliant with the Electronic Logging Device (ELD) mandate of the Federal Motor Carrier Safety Administration (FMCSA).
Follicle-stimulating hormone (FSH) is a gonadotropin, a glycoprotein polypeptide hormone. FSH is synthesized and secreted by the gonadotropic cells of the anterior pituitary gland and regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and luteinizing hormone (LH) work together in the reproductive system.
==== In animals ==== PABA has been referred to historically as "vitamin Bx", but plays no direct role in animal cells and is hence no longer recognized as a vitamin. Animals (including humans) are unable to use PABA in any way and so require folate from dietary sources such as green leafy vegetables. PABA can play a role in the supply of folate to an animal via its microbiome; this is best demonstrated in the worm C. elegans, in which addition of PABA could increase folate production by resident E. coli and correct for deficiencies. The C. elegans folate transporter only works with the reduced form (tetrahydrofolate, THF and derivatives such as folinic acid), not regular folic acid. Any folic acid from the environment is only usable following spontaneous breakdown to PABA-glu, which E. coli uses to make THF. In contrast, humans can directly use oxidized folates thanks to the proton-coupled folate transporter and have no need for this detour; this "recycling" of PABA-glu would, at best, compensate for folate degradation. The above do not seem to apply in normal mammals, however. Despite detection of gut-produced folate being incorporated into mammals, ex vivo folate synthesis capacity of fecal bacteria have no correlation with the folate status of their donors. Furthermore, comparison with germ-free animals show that under a chow diet, the mouse microbiome is a net consumer of folate. The caveat is that the mouse chow is more folate-rich than typical human diets and may be encouraging a shift towards a folate-consuming microbiome.
=== 1978 === January 29: The Chadian–Libyan conflict begins over the Aouzou Strip. March 15: The Ogaden War ends with a cease-fire. March 16: Italian Prime Minister Aldo Moro is kidnapped in Rome by a far-left extremist terrorist group called the Red Brigades. His body would be found on the 9th of May after 55 days of captivity. April 27: President of Afghanistan Sardar Mohammed Daoud's government is overthrown when he is murdered in a coup led by pro-communist rebels. May 11: The second rebellion in the Shaba Province, Zaire occurred. October 1: Tuvalu becomes independent from the UK as a member of the Commonwealth. November 3: Dominica becomes independent from the UK. December 18: Deng Xiaoping announces the reform and opening up of China. December 25: Vietnam invades Cambodia.
Sources: en.wikipedia.org
Validation establishes suitability for a new method, while verification confirms that a method works in a specific laboratory. Verification is often used when a validated method is adopted with existing equipment and staff. Both rely on documented acceptance criteria.
Quantification usually compares detector response to a standard curve made from reference standards. The curve may be external, internal, or based on standard addition depending on matrix effects. Results are reported with units and, when required, uncertainty.
Carryover occurs when analyte from a previous injection remains in the system and appears in a later chromatogram. It can come from the injector, column, or tubing. Blank injections and needle washes help detect and reduce it.
System suitability is a set of checks performed before and during a run to confirm that the instrument, column, and method work as expected. Common checks include resolution, tailing factor, theoretical plates, and relative standard deviation of replicate injections. Failure triggers troubleshooting or method adjustment.