bluuebunny/crossref_metadata_2025 huggingface dataset:
Heme to Protein Linkages in Mammalian Peroxidases: Impact on Spectroscopic, Redox and Catalytic Properties
Authors: Zederbauer Martina , Furtmueller Paul G. , Brogioni Silvia , Jakopitsch Christa , Smulevich Giulietta , Obinger Christian
Published: August 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
N‐Heterocyclic Carbene‐Palladium Complex Catalyzed Oxidative Carbonylation of Amines to Ureas
Authors: Zheng Shu‐Zhan , Peng Xin‐Gao , Liu Jian‐Ming , Sun Wei , Xia Chun‐Gu
Published: August 2007

Palladium carbene shows high efficiency without any promoter on oxidative carbonylation of amines to ureas and a new type of palladium carbene complex containing both an aniline and an NHC ligands was found to be the active species for the reaction.
Development of an Indirect Competitive ELISA Based on Polyclonal Antibody for the Detection of Diethylstilbestrol in Water Samples
Authors: Wang Wen‐Jun , Ling Yun , Xu Ting , Gao Hong‐Bin , Sheng Wei , Li Ji
Published: August 2007

An indirect competitive enzyme‐linked immunosorbent assay (icELISA) based on polyclonal antibody for the estrogen diethylstilbestrol (DES) was developed. With this aim, two different haptens mono‐O‐3‐carboxypropyl‐ diethylstilbestrol (DES‐CP) and mono‐O‐carboxymethyldiethylstilbestrol (DES‐CM) with carboxylic group that preserve the molecular structure character of diethylstilbestrol were synthesized. The haptens were conjugated with the carrier proteins bovine serum albumin (BSA) by mixed‐anhydride method for immunogen and conjugated with ovalbumin (OVA) by active ester method for coating antigen. Polyclonal antibodies for diethylstilbestrol were raised by immunizing mice with immune antigen DES‐CP‐BSA. Under optimized system, the lowest limit of detection (LLD) of diethylstilbestrol was 0.01 ng/mL, and IC50 = 1.02 ng/mL. Its analogs were tested and no obvious cross‐reactivity was found to anti‐diethylstilbestrol antibody. DES‐fortified water samples were determined by simple dilution to diminish the matrix effect. The comparison between the amount of DES estimated by ELISA and the amount added indicates good agreement for all water samples tested, with mean recovery values ranging from 86% to 120.2%.
Isolation and Identification of the Major Chemical Components Found in the Upper Parts of Teucrium Polium Plants Grown in Khuzestan Province of Iran
Authors: Ashnagar Alamdar , Gharib naseri Nahid , Foroozanfar Shahla
Published: August 2007

Teucrium polium is a dwarf sub‐shrub usually 30–60 cm high with many branches, which is fairly distributed throughout Iran, with its flowering being season mainly from April to July. The plant was collected during its flowering season in Baghmalek region in the North‐East of Khuzestan province, Iran. After the identification of the genus, species and variety of the plant, the dried whole plant (flowers, fruits and the leaves) was steam distilled with different methods. The isolated essential oil was dried over anhydrous sodium sulphate and stored at 4–6 °C. Analysis of the essential oil was carried out by GC‐MS technique. At least 10 major components were identified (3‐carene/α‐pinene, β‐phellandrene, limonene, germacrene, β‐bourbonene, β‐caryophylene, (‐muurolene, γ‐elemene, spathulenol, β‐eudesmol) (totally 97.02%). Also, successive TLC and column chromatography of the essential oil resulted in the separation of four fractions. Based upon 1H NMR, IR and mass spectra, the fractions with Rf0.12 and 0.93 were determined as guaiol and a mixture of α‐pinene, β‐phellandrene and limonene, respectively.
Artesunate and Dihydroartemisinin (DHA): Unusual Decomposition Products Formed under Mild Conditions and Comments on the Fitness of DHA as an Antimalarial Drug
Authors: Haynes Richard K. , Chan Ho‐Wai , Lung Chung‐Man , Ng Nga‐Chun , Wong Ho‐Ning , Shek Lai Yung , Williams Ian D. , Cartwright Anthony , Gomes Melba F.
Published: August 2007

Artesunate drug substance, for which a rectal capsule formulation is under development for the treatment of severe malaria, when heated at 100 °C for 39 h gives β‐artesunate, artesunate dimers, 9,10‐anhydrodihydroartemisinin (glycal), a DHA β‐formate ester, and smaller amounts of other products that arise via intermediate formation of dihydroartemisinin (DHA) and subsequent thermal degradation. Solid DHA at 100 °C provides an epimeric mixture of a known peroxyhemiacetal, arising via ring opening to a hydroperoxide and re‐closure, smaller amounts of a 3:1 mixture of epimers of a known tricarbonyl compound, and a single epimer of a new dicarbonyl compound. The latter arises via homolysis of the peroxide and an ensuing cascade of α‐cleavage reactions which leads to loss of formic acid incorporating the C10 carbonyl group of DHA exposed by this 'unzipping' cascade. The tricarbonyl compound that arises via peroxide homolysis and extrusion of formic acid from a penultimate hydroxyformate ester incorporating C12 of the original DHA, is epimeric at the exocyclic 1′′‐aldehyde, and not in the cyclohexanone moiety. It is converted into the dicarbonyl compound by peroxide‐induced deformylation. The dicarbonyl compound is not formed during anhydrous ferrous bromide mediated decomposition of DHA at room temperature, which provides the 1′′‐R epimer of the tricarbonyl compound as the dominant product; this equilibrates at room temperature to the 3:1 mixture of epimers of the tricarbonyl compound obtained from thermolysis. Each of artesunate and DHA decomposes readily under aqueous acidic conditions to provide significant amounts of the peroxyhemiacetal, which, like DHA, decomposes to the inert end product 2‐deoxyartemisinin under acidic or basic conditions. DHA and the peroxyhemiacetal are the principal degradants in aged rectal capsule formulations of artesunate. TGA analysis and thermal degradation of DHA reveals a thermal lability which would pose a problem not only in relation to ICH stability testing guidelines, but in the use of DHA in fixed formulations currently under development. This thermolability coupled with the poor physicochemical properties and relative oral bioavailability of DHA suggests that it is inferior to artesunate in application as an antimalarial drug.
Identification of Hexameric Water and Hybrid Water–Chloride Clusters Intercalated in the Crystal Hosts of (Imidoylamidine)nickel(II) Complexes
Authors: Kopylovich Maximilian N. , Tronova Ekaterina A. , Haukka Matti , Kirillov Alexander M. , Kukushkin Vadim Yu. , Fraústo da Silva João J. R. , Pombeiro Armando J. L.
Published: August 2007

Two structurally related bis(imidoylamidine or 1,3,5‐triazapentadiene)nickel(II) compounds {Ni[HN=C(3‐py)NC(3‐py)=NH]2}·H2O·MeOH (1) and [Ni{HN=C(3‐py)N(H)C(3‐py)=NH}2]Cl2 (2) with symmetrical 3‐pyridyl (3‐py) substituents have been prepared by direct 2‐butanone oxime mediated transformation of 3‐cyanopyridine in the presence of Ni(MeCO2)2·4H2O or NiCl2·2H2O, respectively. Compounds 1 and 2 have been characterized by elemental analyses, IR, 1H and 13C{1H} NMR spectroscopy, and FAB+ mass spectrometry, while their slow recrystallization in air from organic solvents revealed a high affinity for water and resulted in the formation of the derived compounds [Ni{HN=C(3‐py)NC(3‐py)=NH}2]·6H2O (1′) and [Ni{HN=C(3‐py)N(H)0.5C(3‐py)=NH}2]Cl·2H2O (2′). Single‐crystal X‐ray diffraction analyses allowed the identification of discrete hexameric water or hybrid water–chloride clusters hosted by the crystal matrixes of 1′ and 2′, respectively. Both the (H2O)6 and [(H2O)4(Cl)2]2– clusters possess similar geometries and consist of cyclic planar tetranuclear (H2O)4 or [(H2O)2(Cl)2]2– cores with two dangling water molecules. These water associates occupy voids in the crystal cells and display extensive H‐bonding interactions with monomeric nickel–organic units, thus playing a key role in the formation of 3D hydrogen‐bonded supramolecular assemblies. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Squamous cell carcinoma of the head and neck in never smoker–never drinkers: A descriptive epidemiologic study
Authors: Dahlstrom Kristina R. , Little Jarrod A. , Zafereo Mark E. , Lung Margaret , Wei Qingyi , Sturgis Erich M.
Published: August 2007

Background.

While the attributed risk factors for the vast majority of patients with squamous cell carcinoma of the head and neck (SCCHN) are smoking and alcohol abuse, there appears to be a rising proportion of SCCHN patients who report no significant smoking or drinking history. This study reports the demographic and potential risk factors of a large series of never smoker–never drinker (NSND) patients.

Methods.

All subjects were participants in a prospective epidemiologic study of incident SCCHN. We obtained demographic data, clinical characteristics, and potential etiologic factors for 172 NSND patients and 1131 ever smoker–ever drinker (ESED) patients.

Results.

NSND patients were more likely to be female and to present at extremes of age, but overall were significantly younger than ESED patients. NSND patients had a higher proportion of oral cavity and oropharyngeal cancers than ESED patients had. Eleven percent of NSND patients (17% of NSND men) reported regular use of noncigarette tobacco products or marijuana, 41% (45% of NSND women) reported regular environmental exposure to tobacco smoke, 24% (36% of NSND men) reported regular occupational exposures to carcinogens/toxins, and 30% had a history of gastroesophageal reflux disease. More than half the NSND patients with an oropharyngeal primary were serologically positive for human papillomavirus type 16.

Conclusion.

NSND patients with SCCHN are commonly young women with oral tongue cancer, elderly women with gingival/buccal cancer, or young to middle‐aged men with oropharyngeal cancer. While several exposures studied may be important to the etiology of a subset of these cancers in NSND patients, it is likely that no single known factor is responsible for a majority of SCCHN in NSNDs. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Cost of care for early‐ and late‐stage oral and pharyngeal cancer in the California Medicaid population
Authors: Epstein Joshua D. , Knight Tara K. , Epstein Joel B. , Bride Mark A. , Nichol Michael B.
Published: August 2007

Background.

This study documents the direct medical costs associated with treating oral and pharyngeal squamous cell carcinoma (OSCC) as early‐ or late‐stage disease according to the current standard of care.

Methods.

This retrospective analysis of California Medicaid claims data calculated direct payments for patients diagnosed with OSCC. Patients were defined as being treated for early‐ or late‐stage disease based on treatment modality. Regression determined significant predictors of year‐1 cost of care following diagnosis.

Results.

Median year‐1 cost of care following initial diagnosis was $25,319 for the 229 patients identified. Regression results determined that treatment modality and medical comorbidities were significant in predicting costs (p < .05). Costs for patients treated as having early‐stage OSCC were approximately 36% less than for those treated as having late‐stage disease (p = .002).

Conclusion.

Treatment for OSCC is a significant cost from Medicaid's perspective, and these data suggest early detection may ease its economic burden. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Developing educational indicators that will guide students and institutions toward a sustainable future
Authors: Cohen Bert
Published: August 2007

To meet the sustainability challenge, colleges and universities will have to reorient their educational programs. IR can help assess and demonstrate the success of such initiatives.
Determining factors for cryoprotectant accumulation in the freeze‐tolerant earthworm, Dendrobaena octaedra
Authors: Overgaard Johannes , Slotsbo Stine , Holmstrup Martin , Bayley Mark
Published: August 2007

The freeze‐tolerant earthworm Dendrobaena octaedra is found in most of the European forest and tundra, Siberia, North America and Greenland where it over‐winters in the top soil and encounters winter frost. In response to freezing this earthworm rapidly synthesises glucose which acts as a cryoprotectant. Frost tolerance varies extensively between geographical populations, and of the populations studied so far, the Finnish worms are most and the Danish worms least frost tolerant. Little is known about the determining factors for glucose synthesis and this study therefore investigated possible roles of acclimation and the cues for synthesis of glucose, in Finnish and Danish worms. The Finnish population had significantly larger glycogen reserves than the Danish during acclimation and in all worms, glucose synthesis was the result of an almost stoichemical reduction in glycogen stores. Maximum glucose levels were reached after the onset of freezing and were significantly higher in Finnish worms where the sugar accounted for as much as 5% of the fresh weight. On average, both the total glycogen phosphorylase activity and the active enzyme pool increased during acclimation in the Finnish but not the Danish populations. However, the increase in this enzyme was only significant during the freezing process. In this study, we show contrary to previous theory that glucose synthesis is initiated before the onset of freezing and that in this species, cryoprotectant synthesis is sensitive to very small temperature changes below 0°C without the presence of ice. J. Exp. Zool. 307A:578–589, 2007. © 2007 Wiley‐Liss, Inc.
Selection of Ionic Liquids for Free Radical Polymerization Processes
Authors: Strehmel Veronika
Published: August 2007

Summary: Ionic liquids are efficient solvents for free radical homo‐ and copolymerization. Important parameters for selection of ionic liquids are their liquidus range, their viscosity, and their polarity. Viscosity of ionic liquids strongly influences the degree of polymerization of homopolymers. Micropolarity of ionic liquids can be used to explain differences in the composition of copolymers made on the basis of a relatively nonpolar methacrylate and a highly polar zwitterionic methacrylate.
Common tea formulations modulatein vitrodigestive recovery of green tea catechins
Authors: Green Rodney J. , Murphy Angus S. , Schulz Burkhard , Watkins Bruce A. , Ferruzzi Mario G.
Published: August 2007

Epidemiological evidence suggests a role for tea catechins in reduction of chronic disease risk. However, stability of catechins under digestive conditions is poorly understood. The objective of this study was to characterize the effect of common food additives on digestive recovery of tea catechins. Green tea water extracts were formulated in beverages providing 4.5, 18, 23, and 3.5 mgper100 mL epicatechin (EC), epigallocatechin (EGC), epigallocatechin‐gallate (EGCG), and epicatechin‐gallate (ECG), respectively. Common commercial beverage additives; citric acid (CA), BHT, EDTA, ascorbic acid (AA), milk (bovine, soy, and rice), and citrus juice (orange, grapefruit, lemon, and lime) were formulated into finished tea beverages at incremental dosages. Samples were then subjected toin vitrodigestion simulating gastric and small intestinal conditions with pre‐ and post‐digestion catechin profiles assessed by HPLC. Catechin stability in green tea was poor with < 20% total catechins remaining post‐digestion. EGC and EGCG were most sensitive with ⪇ 10% recovery. Teas formulated with 50% bovine, soy, and rice milk increased total catechin recovery significantly to 52, 55, and 69% respectively. Including 30 mg AA in 250 mL of tea beverage significantly (p< 0.05) increased catechin recovery of EGC, EGCG, EC, and ECG to 74, 54, 82, and 45% respectively. Juice preparation resulted in the highest recovery of any formulation for EGC (81–98%), EGCG (56–76%), EC (86–95%), and ECG (30–55%). These data provide evidence that tea consumption practices and formulation factors likely impact catechin digestive recovery and may result in diverse physiological profiles.
Synthesis of graft copolymers of xyloglucan and acrylonitrile
Authors: Mishra Anuradha , Clark James H. , Vij Annu , Daswal Swati
Published: August 2007

Xyloglucan (XG), a water‐soluble food grade polysaccharide is reported as a substrate for the graft copolymerization of acrylonitrile (AN). XG was extracted from tamarind seed mucilage. Polymerization was initiated both by ceric ion in aqueous medium under N2 atmosphere and with microwave (MW) irradiation. The progress of the reaction was monitored gravimetrically. The effect of different reaction parameters such as monomer concentration, level of ceric ammonium nitrate/HNO3 (CAN) initiator, reaction time and temperature, and MW power on the percent grafting (PG) was studied. Grafting of polyacrylonitrile (PAN) onto XG was confirmed by Fourier‐transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscope (SEM) techniques have been used to study the thermal and morphological changes in the materials. Copyright © 2007 John Wiley & Sons, Ltd.
Optimization of injection‐molding process for mechanical properties of polypropylene components via a generalized regression neural network
Authors: Shie Jie‐Ren
Published: August 2007

This study analyzed contour distortions, wear and tensile properties of polypropylene (PP) components applied in the interior coffer of automobiles. A hybrid method integrating a trained generalized regression neural network (GRNN) and a sequential quadratic programming (SQP) method is proposed to determine an optimal parameter setting of the injection‐molding process. The specimens were prepared under different injection‐molding conditions by changing melting temperatures, injection speeds, and injection pressures. Average contour distortions at six critical locations, wear and tensile properties were selected as the quality targets. Sixteen experimental runs, based on a Taguchi orthogonal array table, were utilized to train the GRNN and then the SQP method was applied to search for an optimal setting. The trained GRNN was capable of predicting average contour distortions, wear and tensile properties at various injection‐molding conditions. In addition, the analysis of variance (ANOVA) was implemented to identify significant factors for the molding process and the proposed algorithm was compared with traditional schemes like the Taguchi method and the design of experiments (DOE) approach. Copyright © 2007 John Wiley & Sons, Ltd.
Incorporation of inherent safety principles in process safety management
Authors: Amyotte Paul R. , Goraya Attiq U. , Hendershot Dennis C. , Khan Faisal I.
Published: August 2007

Process safety management (PSM) deals with the identification, understanding, and control of process hazards to prevent process‐related injuries and incidents. Explicit incorporation of the principles of inherent safety in the basic definition and functional operation of the various PSM elements can help to improve the quality of the safety management effort.

Numerous inherent safety examples, both technical and nontechnical, are given in this paper. Existing qualitative and quantitative tools that already include, or could incorporate, inherent safety are described. Recently developed inherent safety tools for quantitative hazard identification and assessment are identified from either the literature or the current authors' work. Qualitative protocols for incorporating inherent safety into PSM elements are also presented. The language of inherent safety, although largely unused in PSM documentation, has a key role to play in enhancing the effectiveness of PSM. © 2007 American Institute of Chemical Engineers Process Saf Prog 2007
Highly efficient bismuth telluride doped p‐type Pb0.13Ge0.87Te for thermoelectric applications
Authors: Gelbstein Yaniv , Dashevsky Zinovi , Dariel Moshe P.
Published: August 2007

Bi2Te3 doped p‐type Pb0.13Ge0.87Te samples were prepared by hot pressing. We report on very high power factor values of ∼30 μW/cm K2 at 500 °C, as were determined from Seebeck coefficient and electrical resistivity measurements. From dilatometric characterization, the phase transition from the low temperature rhombohedral to the high temperature cubic NaCl structures, takes place at 373 °C. This transition is accompanied by a continuous and gradual change of the lattice parameters, as was observed by hot stage XRD, suggesting a good mechanical durability upon thermal cycling and operating in large thermal gradients.

magnified image

Rhombohedral distortion of the cubic NaCl structure of Pb1–x Gex Te upon cooling, characterized by changes in the interaxial angle α and the lattice parameter.

(© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Capillary gas chromatography‐mass spectrometry of resin acids in tall oil rosin
Authors: Holmbom B. , Avela E. , Pekkala S.
Published: August 2007

The resin acid composition of Finnish tall oil rosin was investigated by gas chromatography and mass spectrometry employing open tubular capillary columns. On a column coated with 1,4‐butanediol succinate, 16 resin acids found in tall oil rosin samples were well resolved, and mass spectra could be recorded. All resin acids were confirmed to be of the pimaric and abietic types by gas chromatographymass spectrometry. Eight of the acids were not detected in the corresponding crude tall oils and evidently had been formed during the technical distillation process. The presence of 8,15‐pimaradien‐18‐oic and 8,15‐isopimaradien‐18‐oic acids in the rosin, but not in the crude tall oil, indicates that the pimaric type acids also undergo extensive isomerization during tall oil distillation. Additionally, three dihydroabietic acids and two acids with identical mass spectra, tentatively stereoisomers of 7,9(11)‐abietadien‐18‐oic acid, were formed during the distillation process.
GRASP‐1 is a neuronal scaffold protein for the JNK signaling pathway
Authors: Ye Bing , Yu Wei-ping , Thomas Gareth M. , Huganir Richard L.
Published: August 2007

GRASP‐1 is a neuronally enriched protein that interacts with the AMPA‐type glutamate receptor/GRIP complex. GRASP‐1 can be cleaved by Caspase‐3 in both normal and ischemic brains although the functional significance of this cleavage remains elusive. We investigated signal transduction pathways that might lie downstream of GRASP‐1 and found that GRASP‐1 potently activates JNK pathway signaling, with no effect on ERK signaling. Such JNK pathway activating activity requires binding of GRASP‐1 to both JNK and the upstream JNK pathway activator MEKK‐1. Furthermore, mutations that prevent Caspase 3‐cleavage of GRASP‐1 dramatically inhibit the JNK pathway activating activity of GRASP‐1, suggesting a novel link between Caspase‐3 activation and JNK pathway signaling. These results suggest that GRASP‐1 serves as a scaffold protein to facilitate MEKK‐1 activation of JNK signaling in neurons.
Lateral soft tissue neck X-rays: are they useful in management of upper aero-digestive tract foreign bodies?
Authors: Karnwal A , Ho E C , Hall A , Molony N
Published: August 2007

Objectives:

To assess the value of lateral soft tissue neck X-rays in patients presenting with upper aero-digestive tract foreign bodies.

Design:

Retrospective study.

Inclusion criteria:

(1) Patients referred to the ENT team, via either the accident and emergency department or their general practitioner; (2) a history of a non-aspirated, upper airway, aero-digestive tract foreign body; and (3) a lateral soft tissue neck X-ray taken on admission.

Results:

A total of 62 patients met the inclusion criteria. Twenty-four patients (38.7 per cent) had positive findings on lateral soft tissue neck X-ray. ‘Soft’ signs, such as widened pre-vertebral shadow and loss of lordosis, were seen in all 24 patients, and foreign bodies were visualised in six patients. Overall, lateral soft tissue neck X-rays were helpful in the management of 32 patients (51.6 per cent). Rather worryingly, doctors in the accident and emergency and ENT departments missed 79.2 and 66.6 per cent of the positive findings, respectively.

Conclusions:

A lateral soft tissue neck X-ray is a helpful tool in the management of patients presenting with upper aero-digestive tract foreign bodies. Junior doctors need better radiology training.
Modelling of road surface temperature from a geographical parameter database. Part 1: Statistical
Authors: Chapman Lee , Thornes John E , Bradley Andrew V
Published: August 2007

The variation of road surface temperature across a road network is influenced regionally by meteorological parameters and locally by geographical parameters. A fast and reliable technique is described which allows the continuous collection of high resolution, geographical data including the sky‐view factor which is suitable for use in road climate modelling studies. Then, by use of regression analysis, the relative importance of five geographical parameters (altitude, topography, sky‐view factor, landuse and road construction) is assessed with respect to road surface temperature and atmospheric stability. Results show that sky‐view factors dominate surface temperatures at high atmospheric stability whereas altitude becomes increasingly important as stability decreases. Finally, a statistical road surface temperature model is discussed with the ability to explain up to 75% of the variation of residual road surface temperatures in the study area entirely by the interaction of geographical parameters. Copyright © 2001 Royal Meteorological Society
Statistical interpretation of NWP products in India
Authors: Maini Parvinder , Kumar Ashok , Singh S V , Rathore L S
Published: August 2007

Although numerical weather prediction (NWP) models provide an objective forecast, poor representation of local topography and other features in these models, necessitates statistical interpretation (SI) of NWP products in terms of local weather. The Perfect Prognostic Method (PPM) is one of the techniques for accomplishing this. At the National Center for Medium Range Weather Forecasting, PPM models for precipitation (quantitative, probability, yes/no) and maximum/minimum temperatures are developed for monsoon season by using analyses from the European Centre for Medium‐Range Weather Forecasts. The SI forecast is then obtained by using these PPM models and output from the operational NWP model at the Center. Direct model output (DMO) obtained from the NWP model and the SI forecast are verified against the actual observations. The present study shows the verification scores obtained during the 1997 monsoon season for 10 locations in India. The results show that the SI forecast has good skill and is an improvement over DMO. Copyright © 2002 Royal Meteorological Society.
Measured and estimated evaporation and soil moisture deficit for growers and the water industry
Authors: Clark C
Published: August 2007

Measurements and estimates of evaporation have been routinely carried out for over a century. In the United Kingdom the most well‐known method of estimating evaporation and its derivatives such as soil moisture deficit (SMD) is the Meteorological Office Rainfall and Evaporation Calculation System (MORECS) which is based on the Penman‐Monteith equation. Direct measurements of evaporation have become less common in recent years. A comparison of measurements and estimates of evaporation and SMD at a single site and over two catchment areas is presented in this paper. Measurements of actual evaporation from a grassed lysimeter have been achieved for the period 1995–98 and they agree well with catchment losses over the same time period in two natural catchments, the Upper Brue and Upper Cary. In contrast to this, MORECS estimates of actual evaporation are different by an average of +20% for the Upper Brue catchment and +27% for the Upper Cary catchment. The largest difference is nearly +40% for the Upper Cary catchment. Similarly, there are substantial differences in the estimates of SMD, often up to 50 mm. When local rainfall is used together with MORECS estimates of potential evaporation the discrepancy is reduced but significant differences remain during much of the growing season, although improvements do occur. The results from this paper will be of great importance to growers, water resource planners, engineers who give flood warnings, and to river flow modellers. Copyright © 2002 Royal Meteorological Society.
Efforts to improve predictions of urban winter heating anomalies using various climate indices
Authors: Changnon David , Thompson Jeff , April Tony , Schmidt Eric , Falout Mike , Davis Jon B , Russo Mark
Published: August 2007

Meteorologists who work in the energy commodities market continue to investigate ways to enhance predictions of seasonal temperature anomalies using oceanic/atmospheric indices. This study examines the relationship of three climate indices –ENSO (El Niño/Southern Oscillation), PNA (Pacific North American) and NAO (North Atlantic Oscillation) –to heating degree day (HDD) totals accumulated in 11 cities in the Midwest and northeastern United States, to determine which, if any, has predictive power. The data covers the 48‐year period between 1951/52 and 1998/99, and focuses on two periods either side of 1 January (i.e. the winter months of October–December and January–April). The index most strongly related to the HDD anomalies during both winter periods was NAO. NAO values were negative for cold (above‐average HDD) anomalies occurring prior to and after 1 January, while the NAO values were generally positive during warm (below‐average HDD) anomalies. During cold anomalies, the PNA values were generally positive in the three months before 1 January and negative afterwards, indicating that different atmospheric teleconnection patterns cause similar temperature anomalies in these regions. The relationship between the equatorial Pacific sea‐surface temperatures (SST) data and temperature anomalies was the weakest. Confidence in these relationships increased when the extreme HDD anomaly years were examined. These results indicated that the relationships of climate indices to HDD anomalies exist and that these would be useful in developing and improving seasonal predictions for business applications. Copyright © 2002 Royal Meteorological Society.
Exploration of possible correlates of nutrition awareness and the relationship with nutrition-related behaviours: results of a consumer study
Authors: van Dillen Sonja ME , Jan Hiddink Gerrit , Koelen Maria A , de Graaf Cees , van Woerkum Cees MJ
Published: August 2007

Objectives

To unravel the concept of nutrition awareness, as it relates to risky personal nutrition-related behaviours, and to assess the sociodemographic and psychosocial correlates of nutrition awareness.

Design

Data were collected in a cross-sectional study with the aid of a face-to-face interview-assisted questionnaire that was based on the Precaution Adoption Process Model and Stages of Change Model.

Setting

Dutch consumer homes.

Subjects

Six hundred and three Dutch adults aged 18 to 80 years, selected from a panel.

Results

Our model explains nutrition awareness well (explained variance 53.7%). Psychosocial correlates were involvement with nutrition, health awareness, association with healthy food, perceived relevance of eating less fat, association with necessity, perceived relevance of vitamins, and perceived attributes of independent organisations. Sociodemographic correlates were gender and age. The relationship between nutrition awareness and nutrition-related behaviours proved to be very complicated.

Conclusions

The value of our study is that it unravels the concept of nutrition awareness. Understanding the correlates of nutrition awareness can contribute to a more effective application of behavioural change models. Our results support increasing involvement with nutrition through personalising and tailoring to the motivational stage.
Identification of tropopause using bending angle profile from GPS radio occultation (RO): A radio tropopause
Authors: Narayana Rao D. , Ratnam M. Venkat , Murthy B. V. Krishna , Rao V. V. M. Jagannadha , Mehta Sanjay Kumar , Nath Debashis , Basha S. Ghouse
Published: August 2007

In this paper, it is shown that the altitude of the tropopause can be determined directly from the profile of Bending Angle (α) of GPS RO (hereafter called as Radio Tropopause, RT) instead of from the derived parameter of temperature which needs further assumptions like hydrostatic equilibrium. Above the altitude range of moist atmosphere, the altitude of peak in α′(=dα/dh) profiles above which it decreases for at least 1 km is defined as the RT. The RT altitude is compared with the cold point tropopause (CPT)/lapse rate tropopause (LRT) altitude from independent measurements of temperature by the radiosonde at different stations. A very good agreement is observed between the tropopause altitudes from these two independent techniques. Particularly at polar latitudes, where it is often difficult to identify the tropopause altitude from temperature profiles, the present method is a more reliable means of identifying the tropopause.
Sustainability and Environmental Chemistry in Semi-Arid/Arid Regions: A Unique Research Opportunity with Global Implications
Authors: Rayne Sierra
Published: August 2007

Dr. Sierra Rayne will be speaking on the interplay of sustainability and environmental chemistry in semi-arid and arid regions worldwide. Drawing on his previous, current, and proposed research on organic and inorganic contaminants in aquatic systems, Dr. Rayne will illustrate the importance of multidisciplinary and interdisciplinary approaches towards tackling environmental problems. A key element of his work is looking at chemical dynamics in environmental matrices, and in particular, photochemically generated reactive intermediates and their impact on biological systems and net ecosystem functions. Semi-arid/arid regions also offer unique opportunities to focus on the role of photochemistry in the biogeochemical cycling of oxyanion-forming heavy metals such as arsenic, molybdenum, selenium, and uranium (among others). Given the importance of semi-arid/arid regions in hosting major mineral deposits, multidisciplinary environmental chemistry research can also help make contributions towards sustainability in the worldwide mining industry. These fields offer great opportunities for researchers and students interested in semi-arid/arid landscapes, and understanding the role and impact of these regions on global contaminant fluxes is at the core of Dr. Rayne’s program.
Early Beneficial Effect of Matrix Metalloproteinase Inhibition on Blood—Brain Barrier Permeability as Measured by Magnetic Resonance Imaging Countered by Impaired Long-Term Recovery after Stroke in Rat Brain
Authors: Sood Rohit R , Taheri Saeid , Candelario-Jalil Eduardo , Estrada Eduardo Y , Rosenberg Gary A
Published: August 2007

Proteolytic disruption of the extracellular matrix with opening of the blood—brain barrier (BBB) because of matrix metalloproteinases (MMPs) occurs in reperfusion injury after stroke. Matrix metalloproteinase inhibition blocks the early disruption of the BBB, but the long-term consequences of short-term MMP inhibition are not known. Recently, a method to quantify BBB permeability by graphical methods was described, which provides a way to study both early disruption of the BBB and long-term effects on recovery in the same animal. We used a broad-spectrum MMP inhibitor, BB1101, to determine both the usefulness of the Magnetic resonance imaging (MRI) method for treatment studies and the long-term effects on recovery. Magnetic resonance imaging studies were performed in control ( N = 6) and drug-treated ( N = 8) groups on a dedicated 4.7-T MRI scanner. Adult Wistar—Kyoto underwent a 2-h middle cerebral artery occlusion followed by an MRI study after 3 h of reperfusion, which consisted of T2- and diffusion-weighted techniques. Additionally, a rapid T1 mapping protocol was also implemented to acquire one pre-gadolinium-diethylenetriaminepentaacetic acid baseline data set followed by postinjection data sets at 3-min intervals for 45 mins. The same animal was imaged again at 48 h for lesion size estimation. Data was postprocessed pixel-wise to generate apparent diffusion coefficient and permeability coefficient maps. Treatment with BB-1101 significantly reduced BBB permeability at 3 h, but failed to reduce lesion size at 48 h. Behavioral studies showed impairment in recovery in treated rats. Magnetic resonance imaging allowed for the monitoring of multiple parameters in the same animal. Our studies showed that BB-1101 was an excellent inhibitor of the BBB damage. However, results show that BB-1101 may be responsible for significant deterioration in neurologic status of treated animals. Although these preliminary results suggest that BB-1101 is useful in reducing early BBB leakage owing to reperfusion injury in stroke, further studies will be needed to determine whether the later detrimental effects can be eliminated by shorter time course of drug delivery.
Full and partial gauge fixing
Authors: Shirzad A.
Published: August 2007

Gauge fixing may be done in different ways. We show that using the chain structure to describe a constrained system enables us to use either a full gauge, in which all gauged degrees of freedom are determined, or a partial gauge, in which some first class constraints remain as subsidiary conditions to be imposed on the solutions of the equations of motion. We also show that the number of constants of motion depends on the level in a constraint chain in which the gauge fixing condition is imposed. The relativistic point particle, electromagnetism, and the Polyakov string are discussed as examples and full or partial gauges are distinguished.
Sinuous breakdown in a flat plate boundary layer exposed to free-stream turbulence
Authors: Mans J. , de Lange H. C. , van Steenhoven A. A.
Published: August 2007

In a flat plate boundary layer, perturbed with streaks, breakdown occurs due to a secondary instability acting on the streaks. An experimental study using a water channel with static turbulence grid revealed the presence of a sinuous secondary instability mode in the bypass transition process. Five sinuous instabilities are investigated in detail in the horizontal plane. The streamwise length scale of the sinuous instability is around 40δ300* and the spanwise scale equals around δ300*. Four main features are found in the underlying streak configuration and developing streak-streak interactions. Firstly, all instabilities arise in a streak configuration where two low-speed streaks are located at a small spanwise distance from each other. Patches of low-speed fluid (forming a discontinuity in the streak pattern) are present in the high-speed streaks surrounding the unstable low-speed streak. As a consequence of the streak-streak interactions at the discontinuities, vortices arise in a staggered configuration. Finally, the vortices develop into three-dimensional structures after which the flow falls apart into smaller three-dimensional flow regions.
Linear scaling density matrix perturbation theory for basis-set-dependent quantum response calculations: An orthogonal formulation
Authors: Niklasson Anders M. N. , Weber Valéry
Published: August 2007

Linear scaling density matrix perturbation theory [A. M. N. Niklasson and M. Challacombe, Phys. Rev. Lett. 92, 193001 (2004)] is extended to basis-set-dependent quantum response calculations for a nonorthogonal basis set representation. The generalization is achieved by a perturbation-dependent congruence transform, derived from the factorization of the inverse overlap matrix, which transforms the generalized eigenvalue problem to an orthogonal, standard form. With this orthogonalization transform the basis-set-dependent perturbation in the overlap matrix is included in the orthogonalized Hamiltonian, which is expanded in orders of the perturbation. In this way density matrix perturbation theory developed for an orthogonal representation can be applied also to basis-set-dependent response calculations. The method offers an alternative to the previous solution of the basis-set-dependent response problem, based on a nonorthogonal generalization of the density matrix perturbation theory, where the calculations are performed within a purely nonorthogonal setting [A. M. N. Niklasson et al., J. Chem. Phys. 123, 44107 (2005)].
Interference lithography by a soft x-ray laser beam: Nanopatterning on photoresists
Authors: Ritucci A. , Reale A. , Zuppella P. , Reale L. , Tucceri P. , Tomassetti G. , Bettotti P. , Pavesi L.
Published: August 2007

We have studied the feasibility of high-resolution laser interference lithography using a tabletop 46.9nm, 1.5ns Ar laser, combined with two different optical configurations based on a Lloyd’s mirror interferometer. Using one of these schemes we have encoded periodic grating structures with a half pitch of 42nm and a vertical modulation of 5nm on a commercial PMMA photoresist. Experiments performed with larger half-pitch structures and detailed theoretical calculations demonstrate the potentiality of producing periodic structures with a half-pitch resolution down to 20nm and a height of up to 60nm. The results can be of considerable interest for the development of a complete high-resolution lithographic process operating with the 47nm laser wavelength.
Accurate heat of formation for fully hydridedLaNi5 via the all-electron full-potential linearized augmented plane wave approach
Authors: Zhao Yu-Jun , Freeman A. J.
Published: August 2007

The heat of formation, ΔHf, for La2Ni10H14, an important property for hydrogen storage, was remarkably overestimated in calculations, and has discouraged the use of first principles total energy methods in the search for novel metal hydrides. Here, we employ the all-electron full-potential linearized augmented plane wave method within both the generalized gradient approximation (GGA) and the local density approximation (LDA), along with a unique treatment of the total energy of the H2 molecule, which plays a critical role in ΔHf determinations. The calculated electronic properties indicate that charge transfer from the interstitial region to the H atoms stabilizes LaNi5 hydride. We find the calculated ΔHf (−31.3 kJ∕mol H2) within GGA is in excellent agreement with experiment (∼−32 kJ∕mol H2), as are the predicted geometrical structures for LaNi5 and La2Ni10H14. Surprisingly, although LDA calculations underestimate the volume of LaNi5 by 10.4%, the final value of ΔHf (−31.2 kJ∕mol H2), is also in excellent agreement with experiment.
Magnetic vortex filament flows
Authors: Barros Manuel , Cabrerizo José L. , Fernández Manuel , Romero Alfonso
Published: August 2007

We exhibit a variational approach to study the magnetic flow associated with a Killing magnetic field in dimension 3. In this context, the solutions of the Lorentz force equation are viewed as Kirchhoff elastic rods and conversely. This provides an amazing connection between two apparently unrelated physical models and, in particular, it ties the classical elastic theory with the Hall effect. Then, these magnetic flows can be regarded as vortex filament flows within the localized induction approximation. The Hasimoto transformation can be used to see the magnetic trajectories as solutions of the cubic nonlinear Schrödinger equation showing the solitonic nature of those.
Simple derivation of the vector addition coefficients
Authors: Ulfbeck Ole
Published: August 2007

Two simple operators are constructed in the product space of two angular momenta. Powers of the operators, when acting on selected product vectors, produce vectors with definite total angular momentum and thereby directly yield the vector addition coefficients in a symmetric form.
Selectable resistance-area product by dilute highly charged ion irradiation
Authors: Pomeroy J. M. , Grube H. , Perrella A. C. , Gillaspy J. D.
Published: August 2007

Considerable effort worldwide has been invested in producing low resistance-area (RA) product magnetic tunnel junction sensors for future hard drive read heads. Here the authors present a method of producing tunnel barriers with a selectable RA value spanning orders of magnitude. A single process recipe is used with only the dose of highly charged ions (HCIs) varied. The HCIs reduce the tunnel barrier integrity, providing enhanced conduction that reduces the overall RA product. The final RA product is selected by appropriate choice of the HCI density; e.g., 100HCIs∕μm2 typically results in the RA product being reduced by a factor of 100.
Largely variable electroluminescence efficiency with current and temperature in a blue (In, Ga)N multiple-quantum-well diode
Authors: Yamane Y. , Fujiwara K. , Sheu J. K.
Published: August 2007

Electroluminescence (EL) efficiency of a blue In0.3Ga0.7N multiple-quantum-well diode has been investigated as a function of current between 0.001 and 20mA at various temperatures (20–300K). The low-temperature EL quenching previously observed below 100K at a driving current of 20mA does not occur at 0.001mA and is found to be strongly dependent on the current level. Largely variable temperature-dependent EL quantum efficiency with current suggests that the injected carrier capture efficiency by radiative recombination centers plays a decisive role for determination of the EL efficiency under the forward bias condition.
Multistage optical memory of a liquid crystal diffraction grating in a single beam rewriting scheme
Authors: Jang Eunje , Kim Hak-Rin , Na Yu-Jin , Lee Sin-Doo
Published: August 2007

The authors report on the multistage optical memory of a liquid crystal (LC) diffraction grating fabricated using a dye-dispersed LC/polymer composite medium. Under a single pump beam, the reorientation of dye molecules, confined within spatially periodic interpolymer networks produced by a patterned exposure of ultraviolet light, allows for a pure optic-axis modulation which gives high diffraction efficiency in a planar LC configuration. The resultant multistage optical memory of the LC grating is controlled solely by the polarization state of a single rewriting beam without the use of an erasing step prior to every rewriting process.
First-principles study of the structure, electronic, and optical properties of orthorhombic BiInO3
Authors: Li Chenliang , Wang Hai , Wang Biao , Wang Rui
Published: August 2007

The structural, electronic, and optical properties of orthorhombic BiInO3 were investigated in the framework of the density functional theory. The calculated structural parameters are in agreement with the experimental data. The band structure, density of states, and Mulliken charge population are obtained, which indicates that BiInO3 has an indirect band gap of 2.08eV. Furthermore, its optical properties are also calculated and analyzed in details. It is shown that BiInO3 is a promising dielectric material.
Synthesis and magnetic properties of (Nd1−xSmx)5Fe17 (x=–1) phase
Authors: Saito Tetsuji
Published: August 2007

An investigation of the synthesis of the (Nd1−xSmx)5Fe17 (x=0–1) phase and its magnetic properties is presented. It was found that the (Nd1−xSmx)5Fe17 (x=0–1) phase can be produced by annealing of the amorphous melt-spun ribbon, regardless of the Sm content of the phase. The Curie temperature and coercivity of the (Nd1−xSmx)5Fe17 (x=0–1) phase increased with its Sm content.
Propagation and spatiotemporal summation of electrical pulses in semiconductor nerve fibers
Authors: Samardak A. , Taylor S. , Nogaret A. , Hollier G. , Austin J. , Ritchie D. A.
Published: August 2007

The authors report the propagation and analog summation of electrical impulses in artificial nerve fibers made of submicron p-n wires. These wires model the longitudinal conductivities of K+ and Na+ ions inside and outside a nerve capillary as well as the transverse capacitance of the nerve membrane and the nonlinear conductance of its ion channels. They demonstrate the summation and annihilation of electrical impulses at room temperature which form the basis for making spike timing neural networks.