bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary Fiber Analysis as Non‐Starch Polysaccharides
Authors: Englyst Hans N. , Quigley Michael E. , Hudson Geoffrey J. 
Published: September 2006

AbstractThe original hypothesis on fiber, that a diet with a high content of unrefined plant foods was linked to a low incidence of Western diseases, has been largely confirmed. The plant cell wall encapsulates and thus controls the release of nutrients, including free sugars and starch, from the plant tissue and thereby influences the glycemic response. This ability to influence digestion and absorption, and thus the physiological effects of other nutrients, is an important property of dietary fiber. The other main properties of a high‐fiber diet are increased fermentation and fecal bulk, and binding of potentially toxic substances, e.g. lectins, thus affecting large gut physiology and health. Naturally high‐fiber diets have low contents of fat and sodium, and are a good source of vitamins and minerals. The national dietary guidelines recommend a diet rich in fruit, vegetables and whole‐grain cereals, and thus naturally rich in plant cell‐wall material, the major constituents (approximately 90%) of which are nonstarch polysaccharides (NSP). Food labeling for dietary fiber should help the consumer in the choice of the recommended unfortified, high‐fiber diet. Analysis of NSP represents a good measure of endogenous plant cell‐wall material for most plant foods and NSP values thus provide a very good marker for a high‐fiber diet.The Englyst procedure for the measurement of dietary fiber as NSP involves enzymatic hydrolysis of starch, precipitation of NSP in ethanol, acid hydrolysis of the NSP and measurement of the released constituent sugars by gas–liquid chromatography (GLC), high‐performance liquid chromatography (HPLC) or colorimetry. Values for total, soluble and insoluble NSP may be obtained using any of the end‐point techniques. The detailed information obtained from the chromatographic methods, which identify and quantify the individual constituent sugars, is particularly useful in studies of the relation between intakes of NSP and health; values for the constituent NSP sugars have been published for a wide range of foods.
Electrophoresis and Isoelectric Focusing in Food Analysis
Authors: Cancalon Paul F. 
Published: September 2006

Abstract
Electrophoresis is based on the differential migration of charged components in an electric field. Until recently, gel electrophoresis and particularly sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) were the main electrophoretic techniques used in food analysis. Recently, capillary electrophoresis (CE) has become widely adopted for the monitoring of many food components.
Such rapid development is due to several factors, but especially to speed and versatility. Most often separation can be performed in a few minutes with minimal sample preparation. A new method can be started by filling the capillary with the proper buffer, and new modular instruments can be rapidly fitted with the appropriate detector. Various CE procedures have been developed since the introduction of this technique. Capillary zone electrophoresis (CZE), the basic CE method, consists of a capillary tubing of fused silica with a diameter of 50–150 µm. The tube is filled with a buffer and subjected to an electric field, and under these conditions the positive charged species migrate toward the cathode at a rate determined by their mass‐to‐charge ratios. However, a net movement of the buffer toward the cathode, electroosmotic flow (EOF), is generated within the tube by the ionized capillary wall silanol groups. As a result, all the molecules present in the buffer proceed toward the cathode, the neutral molecules migrate as a single group, and each negative species moves toward the cathode at a rate determined by the difference between the EOF and its anodic attraction. The other main CE techniques are micellar electrokinetic chromatography (MEKC), where an anionic surfactant is added to the buffer to form negatively charged micelles, isotachophoresis (ITP), in which the sample is sandwiched between electrolytes of high and low mobility and the analytes migrate in order of decreasing mobility, and isoelectric focusing (IEF), which is one of the main techniques used in protein gel electrophoresis: amphoteric electrolytes are allowed to migrate in a capillary where they form a pH gradient. In such a gradient, proteins move until they reach their isoelectric point (pI). Many detection techniques have been applied to CE, including direct and indirect ultraviolet (UV) absorption, fluorescence, electrochemical detection and even mass spectrometry (MS).
Most food components can be examined with these techniques, particularly proteins, ions, organic acids, sugars and various plant chemicals.
Enzyme Analysis and Bioassays in Food Analysis
Authors: Powers J.R. 
Published: September 2006

AbstractThe objectives for carrying out analysis of food products include food safety, food quality, meeting regulatory requirements and the control of food processes. Biological entities used in food analyses include enzymes, microbes and antibodies. Based on categories of food analysis general principles of enzyme, immunological and whole organism (microbial) analyses are described. Applications of the use of enzymes for substrate analysis, with examples of their application, are presented. A brief description is given of the use of enzymes as preparative tools in food analysis and of biosensors that use enzymes as elements. Immunological analysis applicable to food systems is given with an emphasis on applications related to food safety. Microbial assays used in food analysis are described including vitamin analysis and protein quality.
Sample Preparation for Food Analysis, General
Authors: Lichon Michael J. 
Published: September 2006

AbstractSample preparation is the obtaining and manipulation of representative portions of a whole prior to subjecting it to any particular analysis. This includes all steps from design and implementation of sampling from the whole, bulk matrix, or population, in such a manner as to represent the whole (or some determinable aspect of the whole), reduction of particle size, mixing, drying, weighing, dilution, and any number of physical or chemical manipulations prior to analysis. These may include apportionment, storage, digestion, extraction, cleanup separation, and derivatization. While the purpose of these essential steps is to enhance precision and accuracy in determining an analyte concentration relating to the whole, each step adds inherent errors to the result. Furthermore, they may contribute to the contamination and deterioration of the sample relative to the original whole. The consistent use of observation, documenting, replication of test portions, recoveries and reference materials should highlight problem areas. These may be reduced, or at least quantified, using the skill of the professional analyst.
Sample Preparation, Headspace Techniques
Authors: Chaintreau Alain 
Published: September 2006

Abstract
Among sample preparation techniques used prior to gas chromatography (GC), headspace sampling (HS) offers many advantages as it only collects vapors that are directly compatible with GC. The main variants are: (1) collection of a fraction of the HS (static headspace, SHS), (2) gas stripping of volatiles from a solution and subsequent trapping in an adsorbent (purge and trap headspace, P&THS), (3) collection and trapping of volatiles from a whole HS in equilibrium with a liquid (static and trapped headspace, S&THS), (4) partition of volatiles between a sample, its HS, and an adsorbent fiber (headspace solid‐phase microextraction (HSSPME)). For each one, a design and some guidelines for qualitative and quantitative use are given, as well as the equation giving the theoretical recovery. Performances are compared between HS techniques and others such as simultaneous distillation extraction (SDE).
A special section is devoted to the timesaving hyphenation of HS to detectors without chromatographic separation like HS‐sensor array and headspace sampling mass spectrometry (HSMS).
Main HS applications in various areas (food, environment, health and biosciences) since the late 1980s are illustrated. In addition, HS appears to be a unique tool to measure thermodynamical constants of volatiles characterizing their partitioning between phases and their interactions with a nonvolatile matrix.
Fluorescence in Forensic Science
Authors: Menzel E. Roland 
Published: September 2006

AbstractEmission spectroscopy, which in the forensic science context historically has meant (carbon) arc spectroscopy, is occasionally still employed in paint examination and some other trace evidence areas, but has largely been replaced by atomic absorption (AA), Fourier transform infrared (FTIR), gas chromatography/mass spectrometry (GC/MS) and other analytical techniques. Notwithstanding its intrinsically very high sensitivity, molecular fluorescence spectroscopy is not utilized as a general technique of forensic analysis either, because spectra tend to be broad and featureless. Fluorescence spectral examination may occasionally be used in areas such as document examination, specifically for ink differentiation in instances of document alteration, but fluorescence spectra as such tend to pertain primarily to the arena of research. This is not to say, however, that the photoluminescence phenomenon is not exploited in criminalistics, the examination of articles of physical evidence recovered from the crime scene. Indeed, it is widely and effectively employed in tagging or labeling modalities and via the inherent fluorescence itself of trace evidence. Fluorescence‐based approaches to authentication of currency and passports, identification of valuables, origin specification of gun powders and explosives, surveillance, and so on, are less directly pertinent to forensic science. These areas of fluorescence tagging will thus not be dealt with in detail. In criminalistics, photoluminescence is today the mode par excellence for ultrasensitive latent fingerprint detection. It is also employed in detection of body fluids, visualization of fibers, ink discrimination, and so on. Thus, the focus in this article will be on visualization and imaging. We begin, however, with discussion of the basic molecular photoluminescence phenomenon and description of some useful spectroscopic measurements, namely luminescence and excitation spectra, and luminescence lifetime determination by time‐gated and phase‐resolved techniques. These set the stage for the latest advances in photoluminescence visualization in physical evidence processing, with emphasis on fingerprints, the most prominent photoluminescence application in forensic science.
Atomic Spectroscopy for Forensic Applications
Authors: Grant Diana M. , Peters Charles A. 
Published: September 2006

AbstractForensic science is a discipline that evolved from the interaction between law enforcement and the scientific community. The typical operating budget of laboratory facilities created to support law enforcement is often far below what is necessary for practical modernization. Hence, routine analyses that require low maintenance and can be readily performed with practical experience were quickly instituted as standard procedures in many such laboratories. As an example, atomic absorption (AA) spectroscopy has served the forensic community for over 40 years and continues to work effectively for such diverse applications as gunshot powder residue analysis and toxicological examinations in suspected heavy metal poisoning cases.These and other traditional forensic applications have also utilized other forms of spectrochemical analysis such as neutron activation. The advantage of the various forms of atomic spectroscopy over these other methods lies in the practical considerations of accessibility and cost as much as in sampling requirements and detection limits. From well established AA methods to the increasing number of forensic applications being developed for laser ablation/inductively coupled plasma mass spectrometry (LA/ICPMS), modern atomic spectroscopy has proven itself to be a compelling and evolving tool in the investigation of forensic evidence.
Capillary Ion Electrophoresis in Forensic Science
Authors: Ferslew Kenneth E. , Hagardorn Andrea N. 
Published: September 2006

AbstractElectrolyte concentrations can be determined in biological specimens by a number of analytical techniques including flame emission spectrophotometry, atomic absorption spectrometry, high‐performance liquid chromatography (HPLC), and potentiometry with an ion‐specific electrode. Capillary ion electrophoresis (CIE) is an adaptation of free zone capillary electrophoresis to a particular electrophoretic analysis of highly mobile low‐molecular‐weight ions.Vitreous humor electrolyte and nitrogenous compound concentrations are often used to determine potential antemortem disease states or the time interval between time of death and time of autopsy (postmortem interval). Potassium ion concentration in the vitreous humor increases after death, and determination of its concentration in vitreous humor is often used to estimate the postmortem interval.Lithium ion is considered valuable in the treatment of certain types of mania and major endogenous depression and is even used in the treatment of cluster headaches. The optimum dosage is best determined by monitoring serum lithium concentrations. Lithium toxicity can occur with elevated serum lithium concentrations and repeated measurement every 3 h of serum lithium concentrations is recommended for intoxicated patients to differentiate acute poisoning from chronic toxicity and to determine the best course of therapy.The development of the CIE methodology reported herein offers a different qualitative and quantitative analytical technique to detect these ions in biological fluids and tissues. Application of CIE analysis for detection and quantitation of potassium and lithium ions in biological fluids and tissues commonly collected and analyzed in clinical and forensic toxicology is described.
Scanning Electron Microscopy in Forensic Science
Authors: Basu Samarendra 
Published: September 2006

AbstractScanning electron microscopy is providing increasingly definitive solutions to criminal problems since its commercial debut in 1965. This has been due to the ability of the scanning electron microscope (SEM) to simultaneously produce several electron probe‐induced signals from the specimen, which generate readily interpretable images of surface topography and material composition. The successful applications of these signals are determined by sample preparation and instrumental parameters. No other microbeam technology combines high resolution (2–5 nm) of the topographic (secondary) electrons with large depth of field for three‐dimensional viewing. The SEM is indeed ideal for stereomicroscopy. The versatility of the SEM stems from its additional capability to process each specimen signal by various contrast enhancement methods, such as line scanning, deflection modulation (DM), area mapping, etc. These methods allow an intuitive, stylistic, and synthetic analysis of the image and are ideal for quality control analysis. Digital SEMs have pioneered in automated image processing and unattended search and analysis of particulates. The combined SEM and energy‐dispersive X‐ray microanalysis (EDX) is the most definitive technique in testing for gunshot residue (GSR) particles, collected by the glue‐lift technique. In the analyses of other trace evidence, such as hair and fibers, in physical matching, and in nondestructive elemental analysis of physical evidence, the SEM/EDX is the most efficient of all microbeam technologies. From firearms, bullet wounds and human bones, to plants, pollen and fungi, the list of criminal evidence examined by SEM/EDX is endless. However, the SEM/EDX is not ideal for quantitative analysis of elements present as traces (<1% w/w). The SEM lacks the three‐dimensional sectioning abilities of scanning beam confocal microscopes. The imaging capabilities of the SEM surpass these limitations. The SEM is, therefore, a major tool in forensic research and investigation.
Aerosols and Particulates Analysis: Indoor Air
Authors: Branisteanu Radu 
Published: September 2006

Abstract
This article is intended to provide information and directions needed in the assessment of indoor aerosols, both in industrial and nonindustrial environments. Section 2 of this material is dedicated to basic explanations needed to understand the scope and directions of the analysis of aerosols in indoor air. It comprises brief considerations about the deposition of particulates in human airways, the characteristics of the particles and aerosol classification. Section 3 describes some widespread types of aerosols found in occupational and domestic environments. The characterization comprises considerations upon chemical composition, size, shape and the influence upon human health. Methods of analysis are also mentioned. Section 4 describes the factors that influence the sampling and storage of aerosols. Section 5 deals with applications of aerosol analysis in industrial hygiene. Sampling, sample preparation and analyse are exemplified on three selected compounds: metallic species, polycyclic aromatic hydrocarbons (PAHs) and silica. Alternative methods for specific applications are presented. Section 6 refers to home and office environments and approaches strategies used for indoor air quality (IAQ) assessment and the analysis of bioaerosols. Section 7 addresses the air standards and their influence upon analytical methodology and instrumentation. Section 8 comprises a brief discussion regarding differences encountered in aerosol analysis in industrial and nonindustrial environments.
Carcinogens, Monitoring of Indoor Air
Authors: Peterson Max R. 
Published: September 2006

Abstract
Carcinogens in indoor air include radioactive radon, a variety of organic compounds, several inorganic species, asbestos fibers, and a large number of chemical species associated with suspended particulate matter (SPM). Within these categories, carcinogens may be grouped byeither chemical class and physical properties or by the methods used to measure them. Generally, measurement methods within a category are at least similar if not identical.
A typical measurement method includes procedures for sampling a known volume of air in a way that quantitatively collects the species of interest, transferring collected samples to a laboratory, and measuring species of interest in the samples using an appropriate validated analysis method. The sampling location may be in the breathing zone of a person (to measure personal exposure) or at a specific location in a building or room (to measure potential for exposure at that location). A sample may be collected very quickly (to obtain a snapshot of carcinogen concentration at a specific time) or very slowly over a period of hours, days, or weeks (to obtain an integrated or average carcinogen concentration).
The analysis method is essentially independent of the sampling location and sampling time, but collection of an adequate quantity of the species of interest is crucial. In general, radon is measured as radiation emitted from the sample; organic compounds are measured using gas or liquid chromatography with an appropriate detector; carcinogenic inorganic species are measured using atomic absorption spectroscopy (AAS) or atomic emission spectroscopy (AES); asbestos fibers are visually counted at high magnification; and particles are extracted with a solvent to quantitatively remove the species of interest, which are then measured using one of the organic or inorganic methods described above. Concentrations of the species of interest can then be calculated by dividing the quantity of each species measured in the collected sample by the volume of air sampled.
Metals in Blood and Urine: Biological Monitoring for Worker Exposure
Authors: Ullucci Paul A. 
Published: September 2006

Abstract
Biological monitoring uses sophisticated analytical techniques for the accurate and precise determination of metals in blood and urine. This provides occupational health professionals with the means to monitor worker exposure to toxic metals. For metals such as lead, cadmium, and mercury, good correlations have been found between the level of the metal in blood and/or urine and health impairment.
Analytical techniques such as graphite furnace atomic absorption spectroscopy (GFAAS) and inductively coupled plasma mass spectrometry (ICP/MS) have been widely used to determine metals in biological samples. Since metals may exist in different forms in blood and urine, chromatographic separation combined with spectroscopic detection has been used to determine metal species. Biological monitoring is an example of how modern analytical chemistry has provided the tools needed to protect the health of workers.
DNAMolecules, Properties and Detection of Single
Authors: Long Zhifeng 
Published: September 2006

AbstractTechnological advances have created more DNA detection systems with more power than ever before. By amplifying the target or its molecular counterpart, the probe, very minute amounts of DNA can be detected or even sequenced. Different technologies give rise to different DNA detection systems. Each system has its merits and limitation. In many applications, detection sensitivity is the parameter of interest. This article first gives an outline of different DNA detection systems and their sensitivities and limits. It then describes how to achieve and prove one‐copy sensitivity. Finally, it discusses the testing strategy, supported by statistics to increase detection confidence. Although the limit of detection (LOD) can be improved with better technology and instrument, the highest sensitivity is set by probability laws. To detect one‐copy of a DNA molecule, one needs to understand the properties of single.
DNAProbes
Authors: Tyagi Sanjay 
Published: September 2006

AbstractHybridization of nucleic acid probes has been a key technique used in the exploration of the molecular biology of the cell. Use of this technique is now expanding into the field of clinical diagnostics for the detection of pathogens and genetic disorders. In a hybridization assay, a labeled nucleic acid probe of a particular sequence is used to detect the presence of a target nucleic acid sequence. The fundamental principals that guide the design of the nucleic acids hybridization probes and assays are reviewed in this article. New improvements that simplify the implementation of these assays and enhance their sensitivity are discussed. Coupling of hybridization with amplification of nucleic acids in vitro, which results in extremely sensitive detection of specific nucleic acids, are also described.
Optical Mapping in Genomic Analysis
Authors: Aston Christopher , Schwartz David C. 
Published: September 2006

Abstract
Optical mapping is a system for the construction of ordered restriction maps from single deoxyribonucleic acid (DNA) molecules. DNA molecules bound to derivatized glass surfaces are cleaved with restriction enzymes and imaged by fluorescence microscopy. Cut sites are visualized as gaps between cleaved DNA fragments, which retain their original order. Optical mapping offers advantages over electrophoretic methods of restriction enzyme analysis, which require separate techniques for separating cleaved DNA fragments and determining fragment order. Furthermore, small amounts of DNA are required for optical mapping analysis. By determining the existence of these sequence‐specific cut sites and the distances between them, a precise landmark map of the DNA sequence can be constructed. Prokaryote and eukaryote DNA can be mapped. Maps can be constructed from both cloned DNA and genomic DNA. Restriction maps can be constructed for whole genomes by overlapping maps derived from individual molecules. Such maps provide a useful scaffold for accurate alignment of sequence contigs generated by a shotgun sequencing approach and a means of comparing populations and strains.