GC

Fabric study. The urban fabric comprises both cross towers and perimeter blocks. The image shows the morphological range of the perimeter block type. Blocks are split into four quadrants allowing for a secondary, pedestrian path system. At certain network crossing points the block system is assimilated to the tower system: each block sponsors one of the quadrants to form a pseudo-tower around a network crossing point.

Twelve aroma compounds were monitored and quantified by dynamic headspace analysis after their addition in refined olive oil model systems with extra virgin olive oil (EVOO) biophenols to simulate EVOO aroma. The influence of polyphenols on aroma release was studied under simulated mouth conditions by using human saliva, and SPME-GC/MS analysis. While few differences were observed in orthonasal assay (without saliva), interesting results were obtained for retronasal aroma. Biophenols caused generally the lowest headspace release of almost all volatile compounds. However, only ethyl esters and linalool concentrations were significantly lower in retronasal than orthonasal assay. Saliva also caused higher concentration of hexanal, probably due to hydroperoxide lyase (HPL) action on linoleyl hydroperoxides. Epicatechin was compared to EVOO phenolics and the behaviour was dramatically different, likely to be due to salivary protein-tannin binding interactions, which influenced aroma headspace release. These results were also confirmed using two extra virgin olive oils.

A high throughput enzyme assay platform, called GENPLAT, was used to guide the development of an optimized mixture of individual purified enzymes from ten ''accessory" and six ''core" enzymes. Enzyme mixtures were optimized for release of Glu, Xyl, or a combination of the two from corn stover pretreated by ammonia-fiber expansion (AFEX). Assay conditions were a fixed enzyme loading of 15 mg/g glucan, 48 h digestion, and 50°C. Five of the ten tested accessory proteins enhanced Glu or Xyl yield compared to the core set alone, and five did not. An 11-component mixture containing the core set and five accessory enzymes optimized for Glu released 52.1% of the available Glu, compared to 38.5% with the core set alone. A mixture optimized for Xyl released 39.9% of the Xyl, compared to 26.4% with the core set alone. We predict that there is still considerable opportunity for further improvement of synthetic mixtures. Furthermore, the strategy described here is applicable to the development of more efficient enzyme cocktails for any pretreatment/biomass combination and for detecting enzymes that make a heretofore unrecognized contribution to lignocellulose deconstruction.

Introduction and objectives: Physical fitness level is a marker of cardiovascular health in young people. The aim of this study was to analyze the effects of a school-based intervention program, focused on increasing the volume and intensity of physical education (PE) sessions, on adolescents' physical fitness. Methods: Sixty-seven adolescents (12-14 years old) from three secondary school classes participated in a 16-week intervention. The classes were randomly allocated to the control group, experimental group 1 (EG1) or experimental group 2 (EG2). The control group received standard PE (2 sessions/week), the EG1 received 4 standard PE sessions/week and the EG2 received four high-intensity PE sessions/week. Aerobic fitness, muscle strength, speed-agility and flexibility were assessed using previously validated field-based tests before and after the intervention. Results: Doubling the number of PE sessions/week resulted in improvements in aerobic fitness and flexibility (P = .008 and P = .04, respectively). Further increases in the intensity of the sessions were related to improvements in speed-agility (P < .001). The maximal oxygen consumption increased by 3 and 5 mL/kg/min in the EG1 and EG2, respectively. No differences were observed for muscle strength.

CITATIONS 11 READS 112 4 authors: Some of the authors of this publication are also working on these related projects: Biomass pyrolysis, gasification, catalytic pyrolysis, catalytic upgrading of pyrolysis oil, Technoeconomic analysis of biomass pyrolysis process, Carbon capture and storage View project CO2 reforming of methane over Ni/MgO Catalysts Promoted with Zr and La Oxides View project

In this review, we summarize the most recent analytical developments aimed at employing Ionic liquids (ILs) in dispersive liquid-liquid microextraction (DLLME). Four main operation modes can be distinguished: (1) conventional IL-DLLME; (2) temperature-controlled IL-DLLME; (3a) ultrasound-assisted, (3b) microwave-assisted or (3c) vortex-assisted IL-DLLME; and, (4) in-situ IL-DLLME. In these modes, the dispersive solvent can be an organic solvent, a surfactant, or a hydrophilic IL. In some cases, a dispersive solvent is not even necessary. We discuss practical applications of IL-DLLME to determine metals and organic compounds in a variety of samples.

Encapsulating properties of skimmed milk powder (SMP) and whey protein concentrate (WPC) for the coating of the essential oil (EO) of oregano (Origanum vulgare L.) and aroma extracts (AE) of citronella (Cymbopogon nardus G.) and sweet marjoram (Majorana hortensis L.) by spray-drying were evaluated. The efficiency of microencapsulation expressed as a percentage of flavoring entrapped into the microcapsules varied from 54.3% (marjoram in WPC) to 80.2% (oregano in SMP). The content of flavoring remaining on the surface of encapsulated oregano EO was remarkably lower (1.1% and 1.4%) as compared with citronella (11.2% and 15.2%) and marjoram (16.7% and 22.1%) AEs encapsulated in SMP and WPC matrixes, respectively. Consequently, the changes in the composition of individual flavor compounds during encapsulation were considerably smaller for oregano EO as compared with citronella and marjoram AEs. The release of aroma compounds from the encapsulated products was assessed by solid phase microextraction (SPME) of headspace volatiles and their analysis by gas chromatography; some differences were observed between the analysed products. However, the effect of SPME fiber polarity was another important factor affecting the amount of extracted aroma compounds from encapsulated flavors. The percentages of nonpolar aliphatic terpenes were higher in the extracts obtained by nonpolar polydimethylsiloxane or bipolar polydimethylsiloxane-divinylbenzene fibers, while the content of oxygenated constituents in most cases was higher on the polar polyacrylate fiber. The latter extracted lower amounts of volatiles during 10 min exposure. The scanning electron microscopy and particle size analysis revealed that microcapsules were well-formed spherically shaped particles; however, SMP coated products had smoother surface as compared to WPC, containing more dents and wrinkles on the capsule surface. Particle size varied from 6 to 280 lm for SMP and from 2 to 556 lm for WPC microencapsulated products.

The simultaneous determination of several odorous trichlorobromophenols in water has been carried out by an in-sample derivatization headspace solid-phase microextraction method (HS-SPME).The analytical procedure involved their derivatization to methyl ethers with dimethyl sulfate/NaOH and further HS-SPME and gas chromatography-mass spectrometry (GC/MS) determination. Parameters affecting both the derivatization efficiency and headspace SPME procedures, such as the selection of the SPME fiber coating, derivatization-extraction time and temperature, were studied. The commercially available polydimethylsiloxane (PDMS) 100 μm and Carboxen-polydimethylsiloxane-divinylbenzene (CAR-PDMS-DVB) fibers appeared to be the most suitable for the simultaneous determination of these compounds. The precision of the HS-SPME/GC/MS method gave good relative standard deviations (RSDs) runto-run between 9% and 19% for most of them, except for 2,5-diCl-6-Br-phenol, 2,6-diCl-3-Br-phenol and-2,3,6-triBrphenol (22%, 25% and 23%, respectively). The method was linear over two orders of magnitude, and detection limits were compound dependent but ranged from 0.22 ng/l to 0.95 ng/l. The results obtained for water samples using the proposed SPME procedure were compared with those found with the EPA 625 method, and good agreement was achieved. Therefore, the in-sample derivatization HS-SPME/GC/MS procedure here proposed is a suitable method for the simultaneous determination of odorous trichlorobromophenols in water.

The volatile constituents of the sterile stems of Equisetum arvense L. (Equisetaceae) were investigated for the first time using GC, GC/MS and 13 C-NMR. Twenty-five compounds were identified. Hexahydrofarnesyl acetone (18.34%), cis-geranyl acetone (13.74%), thymol (12.09%) and trans-phytol (10.06%) were the major constituents. A disk diffusion method was used for the evaluation of the antimicrobial activity of this oil against a panel of microorganisms (bacteria: Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enteritidis; fungi: Aspergillus niger and Candida albicans). The 1:10 dilution of the essential oil of Equisetum arvense L. was shown to possess a broad spectrum of a very strong antimicrobial activity against all tested strains.

~H and ~3C nuclear magnetic resonance (NMR) spectra of phosphatidylethanolamine plasmalogen were studied. Resonances in both spectra were assigned by conventional one-and two-dimensional NMR techniques. Distinctive signals corresponding to the olefinic carbons near the vinyl ether group were shown to be the most useful in both qualitative and quantitative analysis, The plasmalogen content in different fish lipid samples, as determined by ~3C-NMR spectro'scopy, was in good agreement with the data obtained by gas chromatograpy.

This study was carried out to determine the proximate composition, fatty acid profile and biometric data for farm fish species Labeo rohita, Cirrhinus mrigala, Catla catla raised under identical conditions. The analysed fish species were found as source of high polyunsaturated fatty acids with low fat high protein. Fat content of the fish fillets was in range 2.57-3.11 g/100 g. Whereas fat content for feed was 14.90 g/100 g. The protein level for the three fish ranged from 20.00-23.57 g/100 g and in feed it was estimated in the range of 67.70 g/100 g. The palmitic acid and stearic acid were the main saturated fatty acids (SFA), oleic acid was the predominant MUFA while the docosahexanoic acid and eicopentanoic acid were the major PUFA. The percentage of DHA exceeded that of EPA in all fish species analysed. The nÀ3/nÀ6 ratio ranged from 1.69-1.91. PUFA/SFA ratio was much higher in L. rohita (1.40) due to abundance of nÀ3 PUFA, particularly DHA.

Amitrityline and its metabolite nortriptiline are tricyclic antidepressant drugs widely used for the treatment of several psychiatric disorders. Several methods have been published for the determination of these two antidepressant drugs in pharmaceuticals, biological materials and environmental samples. In this review some of analytical techniques such as ultraviolet/visible spectrophotometry, fluorimetry, capillary electrophoresis, and chromatographic methods (gaschromatography and high-performance liquid chromatography) were discussed. Although HPLC and capillary electrophoresis methods are extensively employed in spite of that UV/VIS spectrophotometry are still popular because of the inherent simplicity, low cost, and reliability for determination of drugs in pharmaceutical preparations.

Hybrid plasma catalyst technology has great potential for indoor air purification. However, humidity is a critical parameter in plasma catalytic processes. In this work, several catalysts were tested downstream of a DC corona discharge and the effect of humidity was investigated on both ozone and toluene removal. Next, sorption measurements onto the catalysts were performed for toluene, trichloroethylene and acetone, using an equilibrium partitioning in closed system procedure to explain the obtained results in a quantitative manner.

Co-digestion of rendering and slaughterhouse wastes was studied in laboratory scale semi-continuously fed continuously stirred tank reactors (CSTRs) at 35 and 55°C. All in all, 10 different rendering plant and slaughterhouse waste fractions were characterised showing high contents of lipids and proteins, and methane potentials of 262-572 dm 3 CH 4 /kg volatile solids (VS) added . In mesophilic CSTR methane yields of ca 720 dm 3 CH 4 /kg VS fed were obtained with organic loading rates (OLR) of 1.0 and 1.5 kg VS/m 3 d, and hydraulic retention time (HRT) of 50 d. For thermophilic process, the lowest studied OLR of 1.5 kg VS/m 3 d, turned to be unstable after operation of 1.5 HRT, due to accumulating ammonia, volatile fatty acids (VFAs) and probably also long chain fatty acids (LCFAs). In conclusion, mesophilic process was found to be more feasible for co-digestion than thermophilic process, methane yields being higher and process more stable in mesophilic conditions.

The aim of this paper is to present an acquisition system and experimental measurements of a new micromachined Thermal Conductivity Detector (µTCD), applied downstream of a gas-chromatography (GC) system. We describe simple and innovative electronics for sensor control and data acquisition, outlining the relevant resistance control, native imbalance compensation and automatic gain control (AGC) algorithm. Measurements and sensitivity tests have been carried out by connecting our TCD and acquisition system downstream of the microfluidic section and GC column of a commercial GC system. Comparing the results with those of a complete commercial GC system we observed a similar response and noise. Sensitivity measurements on toluene masses gave very good results, having observed a sensitivity of 15.2±0.6 µVs/ng. This high sensitivity paves the way for using the µTCD in many portable applications like in-line quality control, industrial security and safety. We also show the good operation of the AGC algorithm.

Gum chewing has been shown to improve cognitive performance in adults; however, gum chewing has not been evaluated in children. This study examined the effects of gum chewing on standardized test scores and class grades of eighth grade math students. Math classes were randomized to a gum chewing (GC) condition that provided students with gum during class and testing, or a control condition with no gum (NGC). Participants included 108 students. The math sections of the Texas Assessment of Knowledge and Skills (TAKS) and the Woodcock Johnson III Tests of Achievement (WJ-III), and math class grades were used to assess academic performance. Students in the gum chewing condition improved standardized test scores and maintained higher grades in math class compared to those in the no-gum chewing condition. These results are encouraging as gum chewing may be a cost-effective and easily implemented method to increase student performance. Trial Registration: NCT00792116. Ó

Methods for chlorophenols (CPs) determination (with low limits of detection) that can be applied to real environmental samples (waters, sediments, soils, biological tissues) and food are reviewed. Special emphasis is given to sampling, storage conditions and the application of preconcentration techniques for the determination of CPs using chromatographic methods. Solid phase extraction, solid phase microextraction, stir bar sorptive extraction, liquid phase microextraction, dispersive liquid-liquid microextraction, liquid-liquid-liquid microextraction and purge and trap methods are considered. Methods for microwave and ultrasonic extraction of CPs from solid matrices are also focused.

A detailed overview towards the advancement of graphene based biosensors has been reviewed. The large surface area and excellent electrical conductivity of graphene allow it to act as an "electron wire" between the redox centers of an enzyme or protein and an electrode's surface. Rapid electron transfer facilitates accurate and selective detection of biomolecules. This review discusses the application of graphene for the detection of glucose, Cyt-c, NADH, Hb, cholesterol, AA, UA, DA, and H 2 O 2 . GO and RGO have been used for the fabrication of heavy metal ion sensors, gas sensors, and DNA sensors. Graphene based FETs have also been discussed in details. In all these cases, the biosensors performed well with low working potentials, high sensitivities, low detection limits, and long-term stabilities.

The purpose of this work was to study the appropriateness of polyethylene bags for the preservation of explosive specimens. To this end, specimens of two types of dynamites, Goma-2 EC, containing nitroglycol (EGDN) and dinitrotoluene (DNT), and Goma-2 ECO, containing only EGDN, were placed individually inside bags and introduced into hermetically sealed glass jars, which were stored for a period of time. Losses of volatile compounds were studied by headspace analysis using Gas Chromatography coupled to Mass Spectrometry (GC-MS). The cross-contamination between dynamites was studied by using High Performance Liquid Chromatography with Mass Spectrometry (HPLC-MS) to analyze the extracts obtained after a sequential solvent extraction of these specimens. Polyethylene bags permit the loss of volatile compounds since EGDN and DNT were detected in the headspaces of the jars. Moreover, cross-contamination between dynamites was also demonstrated since DNT content decreased in the dynamite containing this compound and increased in the dynamite that had not contained it.

Archaeological studies always seek for understanding history and draw right pictures about the life in the past in the different civilizations. Consequently, varieties of sciences are applied in these studies to extract the historical information. Hence this study investigated hair samples that were taken from four royal mummies with the aim of obtaining reliable information about the materials used in embalming, health status of these mummies, their age, and hair color that affects its composition. A variety of analytical techniques were applied in this study; digital microscope, polarizing optical microscope, environmental scanning electron microscope coupled with energy-dispersive X-ray unit, Fourier transform infrared spectroscopy, gas chromatography, and Raman spectroscopy analysis. The results showed the significance of hair in biomonitoring health status and determining age. Besides, it was proved that mastic resin has been used in embalming as early as the Second Intermediate Period especially for royal mummies.

Stress, a common if unpredictable life event, can have pronounced effects on physiology and behavior. Individuals show wide variation in stress susceptibility and resilience, which are only partially explained by variations in coding genes. Developmental programing of the hypothalamic-pituitary-adrenal stress axis provides part of the explanation for this variance. Epigenetic approaches have successfully helped fill the explanatory gaps between the influences of gene and environment on stress responsiveness, and differences in the sequelae of stress across individuals and generations. Stress and the stress axis interacts bi-directionally with epigenetic marks within the brain. It is now clear that exposure to stress, particularly in early life, has both acute and lasting effects on these marks. They in turn influence cognitive function and behavior, as well as the risk for suicide and psychiatric disorders across the lifespan and, in some cases, unto future generations.

"La chromatographie en phase gazeuse (CPG) est toujours un outil très utilisé dans le domaine de la chimie analytique et du contrôle, en particulier en chimie environnementale où les besoins deviennent de plus en plus nombreux et variés. Sa popularité s’étend même au grand public par l’intermédiaire des médias, où il n’est pas exceptionnel de voir des appareils de chromatographie en phase gazeuse dans des reportages télévisés sur des thèmes les plus divers (cosmétologie, dopage, archéologie, pétrochimie…).
Cet article fait suite à celui paru en 1998 (1) et il nous a paru intéressant de réactualiser les caractéristiques des appareils de CPG commercialisés en ce début de siècle et de millénaire. Si aucune grande nouveauté technologique n’est apparue dans ce domaine, la grande évolution sur les appareils disponibles se situe surtout au niveau du choix des injecteurs-vaporisateurs proposés par les fabricants. Dans le précédent article, nous avions décrit en détail le fonctionnement des différents détecteurs ; c’est pourquoi, nous allons décrire ici, celui des injecteurs-vaporisateurs classiques. Puis, des tableaux synoptiques des principaux appareils rencontrés sur le marché français seront donnés, en nous basant sur les informations fournies par les constructeurs.
Mots clés : chromatographie en phase gazeuse, appareillage, aspects techniques, injecteur."

Compared to the classical methods of analysis, advanced instrumental methods have received increasing attention due to their highly precise analysis of food micro-/macro-structure. Due to its widespread popularity, yogurt has been the subject of numerous studies. This article discusses major advanced instrumental methods applied to the analysis of set/stirred yogurt reported in the literature. Discussed analytical methods have been categorized into two parts, namely chemical analysis methods (including flavor analysis of yogurt, analysis of milk constituents, and assays of indexes), and structural analysis methods (including textural and rheological analysis as well as microstructural analysis).

Adverse health effect of trans fatty acids (TFAs) are well recognized, which has precipitated efforts to reduce their content in food products. With the decline of dietary TFAs derived from partial oil hydrogenation, interest is focused on the remaining sources of dietary TFAs derived from ruminants (rTFA), deodorized vegetable oils, trans isomerization during frying, and synthetic conjugated FA (CFA) supplements. Partial hydrogenation and heat-treated oils result in a random distribution of TFA isomers, whereas rTFAs contain specific isomers resulting from enzymatic processes. Reviews of human observational and metabolic intervention studies have suggested that consumption of rTFAs at current levels should not raise health concerns. However, these studies were not based on rTFA levels currently sold in retail markets. Current feeding practices of ruminants result in higher total TFAs with trans-18:1 isomers other than vaccenic acid, and many CFAs other than rumenic acid. The definition of TFA adopted by several countries does not distinguish among isolated TFAs of concern and ignores CFAs that should be included in total TFA due to their negative health effects. Accurate TFA definition establishment and nutritional assessment of individual TFA isomers is needed for labeling purposes. Also required are adoptions of analytical methods to resolve all TFA isomers. This information can then be used to construct a database and as a basis for meaningful recommendations.

Modern trends in analytical chemistry are towards the simplification and miniaturization of sample preparation, as well as the minimization of organic solvent used. In view of this aspect, several novel micro-extraction techniques are being developed in order to reduce the analysis step, increase the sample throughput and to improve the quality and the sensitivity of analytical methods. One of the emerging techniques in this area is liquid-phase micro-extraction (LPME). It is a miniaturized implementation of conventional liquid/liquid extraction (LLE) in which only microliters of solvents are used instead of several hundred milliliters in LLE. It is quick, inexpensive and can be automated. In the last few years, LPME has been combined with liquid chromatography (LC) and capillary electrophoresis (CE), besides the generally used coupling to gas chromatography (GC), and has been applied to various matrices, including biological, environmental, and food samples. This work is aimed at providing an overview of the major developments of LPME, coupled with chromatography and CE, as reported in the literature. The paper will focus on the application of the technique to different matrices and the aim is to reveal the panorama of opportunities and to try to indicate the potential of LPME in pesticide analysis. A critical review of the first applications to pesticide analyses is presented in the main part of the manuscript. The optimization of LPME as well as advantages and disadvantages are discussed. It is concluded that, because of its high preconcentration factor, LPME can be introduced with benefit into water analysis for several pesticide groups. In particular, the application of LPME to non-polar pesticides in environmental analysis appears to be promising. However, similar to other micro-extraction techniques, such as solid phase micro-extraction (SPME), serious limitations still remain when analyzing semi-solid and solid environmental, food or biological matrices and/or highly polar compounds. Thus, other pre-concentration techniques may be a good alternative if an analytical problem cannot be sufficiently dealt with LPME.

a b s t r a c t HPLC analysis of drug products containing bisoprolol fumarate and lactose revealed the presence of Nformylbisoprolol, which is a final product of the Maillard reaction. Formulations containing secondary amines and reducing carbohydrates are prone to the condensation of amine and carbonyl functional groups and formation of glycosylamines in pharmaceutically relevant conditions. Further rearrangement occurs in the presence of a nucleophile and leads to the formation of 1-deoxy-1-amino-2-ketose also known as the Amadori Rearrangement Product (ARP). The influence of water content, carbohydrate, and lubricant types on the reaction rate was tested. The reaction progress was monitored by HPLC and UV-Vis spectrophotometry. The structures of intermediates were confirmed by the LC/MS 2 analysis. N-formylbisoprolol -the final reaction product -was synthesised and characterised by LC/MS 2 , H 1 and C 13 NMR.

A reliable gas chromatographic mass spectrometric method has been validated for the determination of trace levels (<10 lgL À1 ) of patulin in apple products and quince jam. The method was based on extraction of patulin with ethyl acetate-hexane, alkalinisation and silylation with N,O-bis-trimethylsilyltrifluoroacetamide with 1% of trimethylchloro-silane. The accurate determination of patulin was achieved by employing commercial 13 C 5-7 patulin labelled as an internal standard, which allowed compensating target analyte losses and enhancement or suppression matrix effects. Limits of detection and quantification of method using real samples were 0.4 and 1.6 lgkg À1 , respectively. Recoveries of patulin from samples spiked at 8-50 lgkg À1 levels ranged between 71% and 89%. The repeatability of measurements (expressed as relative standard deviation) was lower than 16%. The method was successfully applied to the determination of patulin in apple fruit and apple products including juice, cider and baby food, and also in quince fruit and quince jam. A new PCR system for the detection of Penicillium expansum in samples containing highly degraded DNA was developed which permitted the detection of the mould in 2/3 of the samples containing patulin, including juices and jams.

The supercritical fluid is an excellent choice as the chromatographic mobile phase because it allows rapid separation with high efficiency and applications involving enantioresolution are common. Supercritical fluid chromatography (SFC) is increasingly used for analytical, semi-preparative and preparative purification of chiral compounds, including production of enantiomers that are mainly encountered during drug development. SFC can be used as an alternative to HPLC for many drug substances, so it is gaining popularity in the pharmaceutical industry. The main advantages of SFC in separating chiral pharmaceuticals are: high speed, short analysis time, limited environmental impact and high efficiency. The reduction in the use of organic solvents has cost, health, and safety benefits. Due to these advantages, SFC fulfills all the requirements of Green Analytical Chemistry approaches.

In the world most commonly used as well as durable material is concrete. In the field of concrete technology, glass fiber reinforced concrete (GFRC) is the recently introduced material. GFRC has many advantages such as light weight material, steel reinforcement corrosion free and structural deterioration free. So, these are the reason the researchers all over the globe are attempting to develop high performance concrete with the use of glass fibers as well as admixtures. While the combination of fly ash, alkaline liquids, fine and coarse aggregate and glass fibers resulted in the product called as Glass Fiber Reinforced Geopolymer Concrete (GFRGC). This product has many advantages such as high early strength, corrosion and sulphate resistance and low shrinkage. The present work has compared the compressive strength, split tensile strength and flexural strength for GFRC and GFRGC. From this comparison it is observed that except for the flexural strength the normal concrete with the addition of glass fibers shown good results as compared to the geopolymer concrete with the addition of glass fibers. This work is only an accumulation of information about GFRC and the research work which is already carried out by other researchers.

Under the appropriate separation conditions the pulsed discharge helium ionization detector (PDHID) was used to detect hydrogen and methane separated from the matrix components of human breath samples. The sensitivity of this method is over an order of magnitude better than published methods using a flame ionization detector (FID) and a thermal conductivity detector (TCD), and has the further advantage of detecting both analytes with only one detector. Limits of detection were 0.3 ppmv for both hydrogen and methane and the method had a linear dynamic range (LDR) of three orders of magnitude (0.3-400 ppm, v/v). The PDHID was also compared to the FID and the TCD in regard to selectivity, sensitivity and reproducibility for high-speed gas chromatography (HSGC). It was shown that the PDHID is as sensitive as the FID for fast separations but is limited by the difficulty of resolving analyte peaks from O 2 and N 2 . The PDHID was at least three orders of magnitude more sensitive than the TCD for all of the analytes examined.

Seven water treatment works were selected to compare disinfection by-products (DBPs) formed when using chlorination and chloramination. DBPs measured included trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), trihalonitromethane, iodinated THMs and nitrosamines. Generally treatment works that used chloramination were able to meet the European THM regulatory limit of 100 mg L À1 whereas the chlorinated works found it significantly more difficult. There were no significant differences in the levels of nitrogenous DBPs between the treatment works using chlorination or chloramination with the exception of the nitrosamine N-nitrosodimethylamine (NDMA) which was present at one treatment works in one season. (S.A. Parsons).

Diospyros kaki Thunb. (Ebenaceae) is a widely cultivated tree species in some countries of Asia, while in other continents persimmons are mostly considered "exotic" fruits. Peculiar characteristics of this species are a complex sex expression, parthenocarpy and fruit astringency at harvest time, associated with a different composition in polymerized flavan-3-ols. Analytical methods for determining sugars, vitamin C, carotenoids and polyphenols in persimmons were critically reviewed in order to evaluate the overall significance of literature results; the nutritional and nutraceutical properties, together with the health benefits of both astringent and non astringent cultivars, were also overviewed. To these aims, the available literature from the last twenty years and the most important formerly published papers were investigated using SciFinder ® , Elsevier SciVerse, AGRIS, and PubMed search engines. Persimmons resulted rich in sugars (about 12.5 g/100 g FW), being fructose, glucose and sucrose the major components, and in total vitamin C, for which 100-150 g of fresh persimmon supplies the recommended daily amount. Astringent varieties supply higher amounts of sugars than nonastringent ones; conversely, higher concentrations of total vitamin C were found in nonastringent cultivars. The main carotenoid components are β-cryptoxantin (193 μg/100 g FW), β,βcarotene (113 μg/100 g FW) and β,ε-carotene (30 μg/100 g FW). Persimmons are also a good source of polyphenolic compounds such as p-coumaric acid, catechin, epicatechin, epigallo catechin, and condensed proanthocyanidins. This chemical composition, together with in vivo and in vitro studies, suggests a relevant role of persimmon in the protection against free radicals and in the prevention of some human diseases.

Immersion stir bar sorptive extraction-gas chromatography-mass spectrometry was used to analyse the volatile organic components of English vineyard grape juices. Four juices, Huxelrebe, Ortega, Schönburger and Siegerrebe, of the 2004 season, were from a commercial vineyard. The fifth, Madeleine Angevine 7672, of the 2000 vintage, was from a private vineyard. Madeleine Angevine juice exhibited the greatest number (113) of identified volatile components, followed by Siegerrebe, Huxelrebe, Schönburger and Ortega, with 78, 74, 70 and 69, respectively. Many compounds are common to all five varieties and very few of the more concentrated components are unique to a particular variety, except (E)-anethole, estragole and methyl salicylate, which were unique to Madeleine Angevine, for these particular vintages. Of the compounds that are common to more than two varieties, Madeleine Angevine had the highest levels of (E)-ethyl cinnamate, hexanol, (E)-2-hexenol, hotrienol, limonene and (E)-methyl cinnamate. Siegerrebe had the highest concentrations of β β β β β -citronellol, diendiol-I, geraniol, dihydromethyl jasmonate, linalool (32 000 ng/l), (Z)-and (E)-linalool oxide (both furanoid and pyranoid forms) and α α α α α-terpineol. This variety also had high levels of 1-hexanol, (E)-2-hexenal and (E)-2-hexenol. Huxelrebe had the highest concentrations of (E)-2-hexenal and (E)-theaspirane; Schönburger had the highest levels of (Z)-3-hexenol, nerol and nerol oxide; and Ortega had the highest concentrations of β β β β β -damascone and β β β β β -damascenone.

Intestinal function in young animals is influenced by maternal factors, such as alterations in the maternal diet. Glucagon-like peptide 2 (GLP-2) enhances intestinal growth and absorption in mature animals. Glucocorticosteroids induce intestinal maturation in neonates and increase sugar uptake in adult animals. It is not known if maternally administered GLP-2 or glucocorticosteroids have persistent effects on intestinal transport in the offspring. This study was undertaken to determine (1) the influence of maternal GLP-2, dexamethasone (DEX) and GLP-2+DEX on intestinal sugar uptake in postweanling offspring and (2) if alterations in uptake are due to variations in intestinal morphology, sugar transporter abundance or the abundance of selected signals. Nursing rat dams were treated during pregnancy and lactation with GLP-2 (0.1 Ag/g per day sc), DEX (0.128 Ag/g per day sc), GLP-2+DEX or placebo. The offspring were sacrificed 4 weeks after weaning, and glucose and fructose uptake was determined using an in vitro intestinal ring uptake technique. sodium-dependent glucose transporter, glucose transporter (GLUT) 5, GLUT2, sodium potassium adenosine triphosphatase and selected signals were assessed by immunohistochemistry. The treatments did not affect body weights or intestinal morphology. GLP-2 and GLP-2+DEX increased jejunal fructose uptake, and GLP-2+DEX increased the jejunal and ileal maximal transport rate for glucose uptake. Protein kinase B and mammalian target of rapamycin abundance were also increased, while transporter abundance was unchanged. We speculate that these alterations in sugar uptake may be due to changes in the intrinsic activity of the transporters mediated by the phosphatidylinositol-3-kinase pathway. These alterations in uptake may have nutritional implications for the offspring of mothers who may be treated with GLP-2 or glucocorticosteroids. D