bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of hepatic transaldolase exchange activity and its effects on tracer measurements of indirect pathway flux in humans
Authors: Jones John G. , Garcia Paula , Barosa Cristina , Delgado Teresa C. , Caldeira M. Madalena , Diogo Luisa
Published: January 2008

Exchange of hepatic glucose‐6‐phosphate (G6P) and glyceraldehyde‐3‐phosphate via transaldolase modifies hepatic G6P enrichment from glucose or gluconeogenic tracers. Transaldolase exchange was quantified in five healthy, fed subjects following an oral bolus of [1,2,3‐13C3]glycerol (25–30 mg/kg) and paracetamol (10–12 mg/kg). 13C Isotopomers of hepatic G6P were quantified by 13C NMR spectroscopy of urinary glucuronide. [1,2,3‐13C3]‐ and [4,5,6‐13C3]glucuronide isotopomers, representing the conversion of [1,2,3‐13C3]glycerol to G6P via dihydroxyacetone phosphate, were resolved from [1,2‐13C2]‐ and [5,6‐13C2]glucuronide 13C‐isotopomers, derived from metabolism of [1,2,3‐13C3]glycerol via pyruvate and phosphoenolpyruvate. Enrichment of [1,2,3‐13C3]glucuronide was significantly less than that of [4,5,6‐13C3]glucuronide (1.30 ± 0.57% versus 1.67 ± 0.42%, P < 0.05). Also, [1,2‐13C2]glucuronide enrichment was significantly less than that of [5,6‐13C2]glucuronide (0.28 ± 0.08% versus 0.36 ± 0.03%, P < 0.05). Transaldolase and triose phosphate isomerase exchange activities were estimated by applying the 13C‐isotopomer data to a model of hepatic sugar phosphate metabolism. Triose phosphate isomerase exchange was ≈99% complete and did not contribute significantly to the unequal 13C‐isotopomer distributions of the glucuronide triose halves. Instead, this was attributable to 25 ± 23% of hepatic G6P flux undergoing transaldolase exchange. This results in substantial overestimates of indirect pathway contributions to hepatic glycogen synthesis with tracers such as [5‐3H]glucose and 2H2O. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
3D non‐contrast‐enhanced MR angiography with balanced steady‐state free precession dixon method
Authors: Stafford Randall B. , Sabati Mohammad , Mahallati Houman , Frayne Richard
Published: January 2008

Balanced steady‐state free precession (bSSFP) is capable of producing ample fat‐water separation. In the case of the bSSFP Dixon method, the phase between fat and water can be manipulated by setting repetition time (TR) to an odd‐half‐multiple of the cycle time and adjusting the center frequency to acquire fat‐water in in‐phase and opposed‐phase images. Adding an image collected when fat and water are in‐phase to an image in which fat and water are opposed‐phase produces a water‐only image. Of the water signals, arterial blood has the highest T2/T1 contrast, making the arterial signal appear brighter than both venous blood and muscle in the final image. In this study, the bSSFP Dixon method was used to collect coronal water‐only three‐dimensional (3D) volumes at multiple anatomical stations in the legs of five healthy volunteers. The image quality was quantified by region‐of‐interest (ROI) analysis of signal intensities between arterial blood, venous blood, muscle, and fat. The images were also assessed for diagnostic quality by a trained radiologist. The bSSFP Dixon method was successful in producing non‐contrast‐enhanced (NCE) images of the blood vessels in the lower limbs. The work presented here is a proof‐of‐concept for the use of the bSSFP Dixon method for 3D peripheral angiography. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Community cardiopulmonary resuscitation training in Greece
Authors: Konstandinos Hatzakis D. , Evangelos Kritsotakis I. , Stamatia Karadimitri , Thyresia Sikioti , Zacharenia Androulaki D.
Published: January 2008

There is a lack of information about the status and characteristics of community cardiopulmonary resuscitation (CPR) training in Greece. The purpose of this study was to evaluate the knowledge of basic aspects of CPR practice, characteristics of training, and areas in need of improvement to increase CPR competence in the community. Using a random‐digit‐dialing telephone survey, 390 residents of a large county were interviewed. Weighting methods were used to estimate population statistics. Results indicated a low prevalence of current training and lack of basic CPR knowledge, reflecting the limited extent of and access to training. Results suggest the need for a standardized, widespread CPR program. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:165–171, 2008
Synthesis of poly[(decanoic acid)‐block‐styrene] diblock copolymers and their self‐assembly behavior in aqueous medium
Authors: Li Dongshuang , Sha Ke , Li Yapeng , Ai Peng , Liu Xiaotian , Wang Wei , Wang Jingyuan
Published: January 2008

Diblock copolymers, poly[(10‐hydroxydecanoic acid)‐block‐styrene] (PHDA‐b‐PSt), were synthesized by combining enzymatic condensation polymerization of HDA and atom transfer radical polymerization (ATRP) as of St PHDA was first obtained via enzymatic condensation polymerization catalyzed by Novozyme‐435. Subsequently, one terminus of the PHDA chains was modified by reaction with α‐bromopropionyl bromide and the other terminus was protected by chlorotrimethylsilane. The resulting monofunctional macroinitiator was used subsequently in ATRP of St using CuCl/2,2′‐bipyridine as the catalyst system to afford diblock copolymers including biodegradable PHDA blocks and well‐defined PSt blocks. Polymeric nanospheres were prepared by self‐assembly of the PHDA‐b‐PSt diblock copolymers in aqueous medium. Copyright © 2008 Society of Chemical Industry
Effect of transfer film on tribological behavior of polyamide 66‐based binary and ternary nanocomposites
Authors: Yu Sirong , Hu Haixia , Zhang Yingbo , Liu Yaohui
Published: January 2008

BACKGROUND: In a polymer–metal sliding system, the formation and performance of the transfer film have important effects on the tribological behavior of the polymer. In order to reveal the wear mechanism of polyamide 66 (PA 66) and its composites consisting of styrene–(ethylene/butylene)–styrene triblock rubber grafted with maleic anhydride (SEBS‐g‐MA) particles and organoclay nano‐layers, the tribological behavior and transfer films of polyamide 66 and its composites were investigated under dry sliding.

RESULTS: The incorporation of SEBS‐g‐MA rubber particles reduces the wear mass loss of PA 66, while the addition of organoclay nano‐layers increases the wear mass loss. The transfer films formed by neat PA 66 and PA 66/organoclay binary nanocomposite include a dark portion and bright portion. In the dark portion, the transfer film is thicker; in the bright portion, the steel ring surface is exposed. The transfer film formed by PA 66/SEBS‐g‐MA/organoclay ternary nanocomposite is thinner and more uniform than the transfer films formed by the other materials.

CONCLUSION: When SEBS‐g‐MA rubber particles and organoclay nano‐layers are added simultaneously to PA 66, the wear resistance of PA 66 can be improved markedly. The main reason is that PA 66/SEBS‐g‐MA/organoclay ternary nanocomposite can form a thin and uniform transfer film on the steel ring surface. Copyright © 2008 Society of Chemical Industry
Versatile synthesis of self‐assembling ABA triblock copolymers with polymethyloxazoline A‐blocks and a polysiloxane B‐block decorated with supramolecular receptors
Authors: Theogarajan Luke , Desai Salil , Baldo Marc , Scholz Carmen
Published: January 2008

BACKGROUND: Self‐assembling amphiphilic block copolymers with incorporated, biologically relevant functionalities have received limited attention, partly due to the fact that biomolecules are not robust enough to synthetic manipulation, do not lend themselves readily to systematic studies due to their complexity and leach rather quickly from a vesicle or membrane when physically incorporated. Synthetic supramolecules are used as biomolecule mimics in functional membranes.

RESULTS: Reaction conditions were established for the synthesis of a tosyl‐terminated siloxane end‐blocker, which serves as molecular weight control in the synthesis of polydimethylsiloxane (PDMS) and poly(dimethylsiloxane‐co‐methylhydrosiloxane) [P(DMS‐co‐MHS)] copolymers. Hydrosilylation reactions were investigated for the covalent coupling of synthetic supramolecules (18‐crown‐6 ether, hydroxybenzoate) to the polymer backbone using the methylhydrosiloxane repeat units as the anchor moiety. Using P(DMS‐co‐MHS) or derivatized P(DMS‐co‐MHS) copolymers as macroinitiator for the ring‐opening polymerization of 2‐methyl‐4‐hydroxy‐oxazoline led to the formation of poly[(dimethylsiloxane‐co‐methylhydrosiloxane)‐block‐oxazoline] [P(DMS‐co‐MHS‐b‐Ox)] ABA triblock copolymers with defined PDMS to PMHS ratios and controlled molecular weights.

CONCLUSION: Derivatized P(DMS‐co‐MHS‐b‐Ox) ABA triblock copolymers synthesized using a novel versatile procedure undergo vesicle formation upon electroformation with vesicle diameters ranging from 2 to 10 µm. The size of the vesicle depends on the overall polarity of the macromolecule. Copyright © 2008 Society of Chemical Industry
Exforge: ARB/CCB combination for better hypertension control
Authors: Chaplin Steve , McInnes Gordon
Published: January 2008

Exforge is a combination of the ARB valsartan and the CCB amlodipine to treat patients whose blood pressure is not controlled with either component. In our review, Steve Chaplin presents the clinical data relating to its efficacy and adverse effects, and Professor McInnes comments on its role in hypertension. Copyright © 2007 Wiley Interface Ltd
Nonmedical prescribing for patients in long‐term care
Authors: Barnett Nina
Published: January 2008

Our series Nonmedical prescribing gives an overview of the work that can be done by nonmedical prescribers and what can be achieved. Here, the author describes her role as a nonmedical prescriber in the long‐term care setting. Copyright © 2007 Wiley Interface Ltd
Practice‐based commissioning: what can pharmacists offer?
Authors: Chaplin Steve
Published: January 2008

Steve Chaplin reviews a new guide from the NHS Alliance and Primary Care Pharmacists' Association that describes the pharmacist services available to practice‐based commissioners. Copyright © 2007 Wiley Interface Ltd
Synthesis, cardiostimulatory, and cardioinhibitory effects of selected insect peptides on Tenebrio molitor
Authors: Szymanowska‐Dziubasik K. , Marciniak P. , RosińSki G. , Konopińska D.
Published: January 2008

The subject of these studies was a search for proctolin antagonists among peptides originating from insect species because the proctolin antagonists constantly pose a problem. During these studies we performed the synthesis of the following peptides: a native decapeptide from Manduca sexta Mas‐MT‐I and its 11 analogs with shortened sequences at the N‐end as well as a growth suppressor, a pentapeptide isolated from Antheraea yamamai, Any‐GS and its 10 analogs, modified at position 1 and with a shortened peptide chain.

Biological effects were evaluated by the cardiotropic test on the semi‐isolated heart of the insect species Tenebrio molitor. Mas‐MT‐I and six analogs stimulate the heartbeat frequency, especially [6–10]‐Mas‐MT‐I, whereas the [4–10]‐Mas‐MT‐I analog shows a strong inhibition of the heartbeat frequency, if insect. The Any‐GS and the analogs [Gln1]‐ and [Gly1]‐Any‐GS also show a strong cardioinhibitory effect. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Template‐directed supramolecular assembly of a new type of nanoporous peptide‐based material
Authors: Görbitz Carl Henrik , Rise Frode
Published: January 2008

Dipeptides with two hydrophobic residues are known to often form crystals with hydrophobic or hydrophilic channels. One of the exceptions is Leu–Ile, which has been previously shown to crystallize as a nonporous 0.75 hydrate in the hexagonal space group P61 with Z′ = 4. We have now found that in the presence of D‐Leu, a second pseudopolymorph of the dipeptide is formed. The crystal structure has hydrophilic, water‐filled channels with an irregular cross section of approximately 5.5 × 3.5 Å and constitutes the first example of a crystal packing arrangement where the direction of the channels is perpendicular to the direction of hydrophobic stacking of side chains rather than parallel as in all other porous peptide‐based materials. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Deep levels associated with dislocation annihilation by Al pre‐seeding and silicon delta doping in GaN grown on Si(111) substrates
Authors: Soh C. B. , Zang K. Y. , Wang L. S. , Chow S. Y. , Chua S. J.
Published: January 2008

The introduction of Si burst during the growth of GaN film on Si(111) substrate by MOCVD formed a Six Ny layer which leads to an effective reduction in the density of screw dislocations. The reduction is associated with bending of screw dislocations to form a square dislocation loop when neighbouring dislocations with opposite Burger's vector paired up. The concentration of electron traps Ec–Et ∼0.17–0.26 eV which is associated with screw dislocations is substantially reduced and a kink is left at the silicon rich position. The mixed‐edge dislocation, however, is not annihilated by the Six Ny layer. Addition of TMAl burst for the AlN growth leads to a substantial reduction in trap concentration associated with the nitrogen vacancies, VN, and antisite of nitrogen, NAl, at Ec–Et ∼0.10 eV and Ec–Et ∼ 0.60 eV respectively. This improves the quality of the subsequent layer of HT‐GaN grown and is useful for device fabrication. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An electrospray ionization tandem mass spectrometric study of p‐tert‐butylcalix[6]arene complexation with ammonium hydroxide, and ammonium and sodium ions
Authors: Sassine André , Martins‐Júnior Helio A. , Lebre Daniel T. , Valli Felipe , Pires Maria A. F. , Vega Oscar , Felinto Maria C. F. C.
Published: January 2008

The formation of complexes involving p‐tert‐butylcalix[6]arene with neutral and charged species has been investigated by tandem mass spectrometry combined with electrospray ionization. Complexes of p‐tert‐butylcalix[6]arene with NH ions were observed in the ratios 1:1, 2:1, and 3:1, together with the complexes of p‐tert‐butylcalix[6]arene with NH4OH and Na+ ions in the ratios 1:1:1, 2:1:1, and 3:1:1. A single 1:1 complex of p‐tert‐butylcalix[6]arene with Na+ ions was observed. In addition, a doubly charged complex of p‐tert‐butylcalix[6]arene with NH4OH, Na+, and NH ions in the ratio 6:1:1:1 was observed. The identity of each complex was determined by mass analysis of product ions formed by the application of a declustering potential over the range 20–220 V and by observation of product ion mass spectra wherein the collision energy was varied from 5 to 50 eV. Fragmentation of the complexes is characterized by the facile loss of the ammonia molecule, sodium and ammonium ions, loss of neutral p‐tert‐butylcalix[6]arene, and successive neutral losses of C4H8 from the six tert‐butyl groups in each p‐tert‐butylcalix[6]arene molecule. Copyright © 2008 John Wiley & Sons, Ltd.
Sensitive determinations of stable nitrogen isotopic composition of organic nitrogen through chemical conversion into N2O
Authors: Tsunogai Urumu , Kido Tadasuke , Hirota Akinari , Ohkubo Satoru B. , Komatsu Daisuke D. , Nakagawa Fumiko
Published: January 2008

We present a method for high‐sensitivity nitrogen isotopic analysis of particulate organic nitrogen (PON) in seawater and freshwater, for the purpose of determining the aquatic nitrogen fixation rate through the 15N2 tracer technique for samples that contain a low abundance of organisms. The method is composed of the traditional oxidation/reduction methods, such as the oxidation of PON to nitrate (NO) using persulfate, the reduction of NO to nitrite (NO) using spongy cadmium, and further reduction of NO to nitrous oxide (N2O) using sodium azide. Then, N2O is purged from the water and trapped cryogenically with subsequent release into a gas chromatography column to analyze the stable nitrogen isotopic composition using continuous‐flow isotope ratio mass spectrometry (CF‐IRMS) by simultaneously monitoring the NO+ ion currents at masses 30, 31, and 32. The nitrogen isotopic fractionation was consistent within each batch of analysis. The standard deviation of sample measurements was less than 0.3‰ for samples containing PON of more than 50 nmolN, and 0.5‰ for those of more than 20 nmolN, by subtracting the contribution of blank nitrogen, 8 ± 2 nmol at final N2O. By using this method, we can determine δ15N for lower quantities of PON better than by other methods, so we can reduce the quantities of water samples needed for incubation to determine the nitrogen fixation rate. In addition, we can expand the method to determine the nitrogen isotopic composition of organic nitrogen in general, such as that of total dissolved nitrogen (TDN; sum of NO, NO, ammonium, and DON), by applying the method to filtrates. Copyright © 2008 John Wiley & Sons, Ltd.
Mass spectrometry and hydrogen/deuterium exchange measurements of alcohol‐induced structural changes in cellular retinol‐binding protein type I
Authors: Torta Federico , Elviri Lisa , Careri Maria , Mangia Alessandro , Cavazzini Davide , Rossi Gian Luigi
Published: January 2008

To bind and release its ligand, cellular retinol‐binding protein type I (CRBP) needs to undergo conformational and dynamic changes to connect the inner, solvent‐shielded cavity, where retinol is found to bind, and the outside medium. Retinol dissociation in vitro is favoured by water/alcohol mixtures whose moderately low dielectric constants mimic a property characteristic of the membrane microenvironment where this process occurs in vivo. Apo‐ and holo‐CRBP, in either water/methanol or water/trifluoroethanol (TFE) mixtures, were analyzed at equilibrium by electrospray ionization with orthogonal quadrupole time‐of‐flight mass spectrometry (ESI‐Q‐TOFMS) to identify the alcohol‐induced species. The questions were asked whether the presence of alcohols affects protein dynamics, as reflected by hydrogen/deuterium (H/D) exchange monitored by continuous‐labelling experiments, and to which extent retinol dissociation influences the process. With increasing methanol, at pH near neutrality, apo‐CRBP exhibits a progressively more compact conformation, resulting in reduced H/D exchange with respect to the native protein in water. Retinol dissociation from the holo‐protein did not promote hydrogen replacement. Similarly, in the presence of the low TFE concentration sufficient to cause retinol dissociation, the hydrogen exchange of the resulting apo‐protein was not exalted. However, in contrast with the alkanol, higher TFE concentrations induced a transition of apo‐CRBP to a new α‐helix conformation capable of exchanging all available hydrogen atoms. Copyright © 2008 John Wiley & Sons, Ltd.
Quantitative analysis of polybrominated diphenyl ethers in earthworms and soil by gas chromatography coupled to ion‐trap tandem mass spectrometry
Authors: Zhu Lingyan , Ma Baoling , Liang Xianwei
Published: January 2008

A method coupling gas chromatography to ion‐trap tandem mass spectrometry (GC/ITMS) was developed and optimized for the analysis of polybrominated diphenyl ethers (PBDEs) in soil and earthworms. It was found that the molecular ion [M]+ cluster provided better performance than the [M‐2Br]+ as a collision‐induced dissociation (CID) precursor ion for most congeners when considering sensitivity, specificity and potential interference from complicated matrices. Other parameters such as the resonant excitation voltage, ‘q’ value, were also optimized. To evaluate the suitability of the ITMS method, the optimized method was applied for the analysis of PBDEs in different samples including earthworms and soil, and its performance was compared with that of selected ion monitoring (SIM). It was found that ITMS offered higher sensitivity than SIM when analyzing real environmental samples. Copyright © 2008 John Wiley & Sons, Ltd.
Raising cognitive load with linear multimedia to promote conceptual change
Authors: Muller Derek A. , Sharma Manjula D. , Reimann Peter
Published: January 2008

Two disparate research programs have addressed the challenge of instructional multimedia design. One, based on cognitive load theory, has focused on ways of reducing unnecessary cognitive load during instruction to free up resources for learning. The other, based on constructivism, has centered on interactive multimedia, allowing students to build their own knowledge. Attempting to build on both bodies of literature, in this study, we investigated techniques that can raise the useful cognitive load engendered with linear multimedia. Participating online from home, students were pre‐ and posttested around a short multimedia intervention that explained Newton's first and second laws. In Experiment 1, students who watched a video dialogue involving alternative conceptions reported investing greater mental effort and achieved higher posttest scores than students who received a standard lecture‐style presentation. In Experiment 2, two additional multimedia treatments were evaluated to assess the role of instructional time and the method of addressing alternative conceptions. In all, 272 students participated in the experiments. Interviews suggest that students adopted a more active approach to understanding the material if alternative conceptions were raised. In addition, students who watched the dialogue judged themselves to be similar to the student in the multimedia. © 2008 Wiley Periodicals, Inc.Sci Ed92:278–296, 2008
Beyond the scientific method: Model‐based inquiry as a new paradigm of preference for school science investigations
Authors: Windschitl Mark , Thompson Jessica , Braaten Melissa
Published: January 2008

One hundred years after its conception, the scientific method continues to reinforce a kind of cultural lore about what it means to participate in inquiry. As commonly implemented in venues ranging from middle school classrooms to undergraduate laboratories, it emphasizes the testing of predictions rather than ideas, focuses learners on material activity at the expense of deep subject matter understanding, and lacks epistemic framing relevant to the discipline. While critiques of the scientific method are not new, its cumulative effects on learners' conceptions of science have not been clearly articulated. We discuss these effects using findings from a series of five studies with degree‐holding graduates of our educational system who were preparing to enter the teaching profession and apprentice their own young learners into unproblematic images of how science is done. We then offer an alternative vision for investigative science—model‐based inquiry (MBI)—as a system of activity and discourse that engages learners more deeply with content and embodies five epistemic characteristics of scientific knowledge: that ideas represented in the form of models are testable, revisable, explanatory, conjectural, and generative. We represent MBI as an interconnected set of classroom conversations and provide examples of its implementation and its limitations. © 2008 Wiley Periodicals, Inc. Sci Ed 92:941–967, 2008
ToF‐SIMS study of 1‐dodecanethiol adsorption on Au, Ag, Cu and Pt surfaces
Authors: Laiho Taina , Leiro Jarkko A.
Published: January 2008

Time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) has been used to perform a chemical analysis of long‐chain thiol (CH3(CH2)11SH)‐treated gold, silver, copper and platinum surfaces. All the mass peaks from positive and negative ion spectra within the range m/z = 0–2000 u are studied. ToF‐SIMS data revealed that on gold, silver and copper substrates 1‐dodecanethiol form dense standing‐up phases, but on platinum being a catalytically active substrate, we were able to identify also surface‐aligned parallel lying molecules in addition to a standing thiolate layer. Our study shows that when ToF‐SIMS spectra are analyzed, not only the existence of oligomers but also metal + hydrocarbon fragments give information about the order of SAM. Copyright © 2008 John Wiley & Sons, Ltd.
Assessing the exposure of German and Austrian bird ringers to West Nile virus (Flavivirus) and evaluating their potential risk of infection
Authors: Linke Sonja , Muehlen Marion , Niedrig Matthias , Ellerbrok Heinz , Kaiser Andreas , Fiedler Wolfgang , Sonnenberg Karen , Alpers Katharina , Stark Klaus , Pauli Georg
Published: January 2008

West Nile virus (WNV) is a mosquito-borne Flavivirus with birds as its natural reservoir. Mosquitoes are able to transmit WNV to humans. In Europe, WNV is most probably imported by migrating birds from WNV-endemic regions. In this study, the risk of WNV infection during bird-ringing activities in Germany and Austria was investigated. Several serological test systems were used to study WNV antibody prevalence among 137 bird ringers. Neutralising antibodies were detected in three of the bird ringers. This seropositivity could be explained by alternative factors such as traveling to endemic areas. The application of different serological methods showed that WNV IgG ELISAs were less specific than WNV IgG immunofluorescence tests (IFT). The neutralisation test (NT) appears to be the gold standard for Flavivirus differentiation. At present, we assume that bird-ringing activity in Germany and Austria harbours a very low risk of WNV infection.
Philopatry of winter moult area in migratory Great Reed Warblers Acrocephalus
arundinaceus demonstrated by stable isotope profiles
Authors: Yohannes Elizabeth , Bensch Staffan , Lee Raymond
Published: January 2008

Stable carbon- (δ13C), nitrogen- (δ15N) and hydrogen (δD) isotope profiles in feathers of migratory Great Reed Warblers Acrocephalus
arundinaceus recaptured for 2 or more years in 6 successive years were examined to test whether the isotope profiles of individual warblers appeared to be consistent between years. Similar isotopic signatures in successive years suggested that individual birds tended to return and grow their feathers in Afro-tropical wintering habitats that generate similar δ13C, δ15N and δD signatures. Previous studies have shown that Great Reed Warblers exhibit strong natal and breeding philopatry, with most of the surviving birds returning to the breeding site. The present study of feather δ13C, δ15N and δD isotopic values demonstrate the year-to-year fidelity might also include the African moulting sites in this migratory species.
Perioperative Workflow: Barriers to Efficiency, Risks, and Satisfaction
Authors: Fowler Patricia H. , Craig Janet , Fredendall Lawrence D. , Damali Uzay
Published: January 2008

AN IN‐DEPTH, INTERDISCIPLINARY CASE study was conducted to map and describe the information, material, and functional processes common to high‐volume surgical specialty procedures at a southeastern US hospital.

RESEARCHERS IDENTIFIED PROCESS defects and their effects using both observation and staff member interviews.

OUTDATED INFORMATION and structural barriers to communications were responsible for many procedural delays, procedural interruptions, and staff member work‐arounds.

OPPORTUNITIES FOR IMPROVEMENT are identified, including redesigns and enhancement of information technology systems. AORN J 87 (January 2008) 187‐208. © AORN, Inc, 2008.
Sterilization: Would Your Facility Pass a Standards Audit?
Authors: Hughes Chuck
Published: January 2008

PROPER STERILIZATION of reusable medical instruments, supplies, and devices and maintaining the sterility of these items until they are used are critical aspects of infection control. To minimize risk, perioperative managers should perform sterilization audits to test their facilities.

THIS ARTICLE guides the reader through a systematic, comprehensive, sterilization audit that evaluates facility design, personnel training, and processing procedures. AORN J 87 (January 2008) 176‐182. © AORN, Inc, 2008.
Maternal consumption ofLactobacillus plantarum299v affects gastrointestinal growth and function in the suckling rat
Authors: Fåk Frida , Ahrné Siv , Molin Göran , Jeppsson Bengt , Weström Björn
Published: January 2008

After birth, the gastrointestinal (GI) tract undergoes vast structural and functional adaptations to be able to digest mother's milk and later, during the weaning period, solid food. Studies on germ-free animals have shown the role of the gut microbiota for stimulating GI maturation, but which groups are involved is unclear. In the present study, we administered the probiotic bacterium,Lactobacillus plantarum299v (Lp299v), in the drinking water to pregnant and lactating rat dams until their pups had reached an age of 14 d. It was found that Lp299v colonizing the mothers were also able to colonize the pups, which had an impact on their gut growth and function. The small intestine, pancreas and liver weighed more in the 14 d-old pups born from dams exposed to Lp299v than in the control pups from dams given only water. Furthermore, the Lp299v pups showed decreased gut permeability. Despite a heavier spleen in the Lp299v pups, as compared to the control pups, no significant increase in the acute-phase protein, haptoglobin, was found. In conclusion, the results reported here clearly show that manipulating the maternal microflora by exposing expecting mothers to a Gram-positive, probiotic bacterium prior to parturition and during lactation impacts the gut growth and function in the offspring.
EXISTENCE OF SOLUTIONS FOR A SYSTEM INVOLVING SCHRÖDINGER OPERATORS WITH WEIGHTS
Authors: Cardoulis Laure
Published: January 2008

In this paper, we obtain some results on the existence of solutions for the system

$$ (-\Delta+q_i)u_i=\mu_im_iu_i+f_i(x,u_1,\dots,u_n)\text{ in }\mathbb{R}^{N},\quad i=1,\dots,n, $$

where each of the $q_i$ are positive potentials satisfying $\lim_{|x|\rightarrow+\infty}q_i(x)=+\infty$, each of the $m_i$ are bounded positive weights and each of the $\mu_i$ are real parameters. Depending upon the hypotheses on $f_i$, we use either the method of sub- and supersolutions or a bifurcation method.
CONSTANT MEAN CURVATURE HYPERSURFACES IN WARPED PRODUCT SPACES
Authors: Alías Luis J. , Dajczer Marcos
Published: January 2008

We study hypersurfaces of constant mean curvature immersed into warped product spaces of the form $\mathbb{R}\times_\varrho\mathbb{P}^n$, where $\mathbb{P}^n$ is a complete Riemannian manifold. In particular, our study includes that of constant mean curvature hypersurfaces in product ambient spaces, which have recently been extensively studied. It also includes constant mean curvature hypersurfaces in the so-called pseudo-hyperbolic spaces. If the hypersurface is compact, we show that the immersion must be a leaf of the trivial totally umbilical foliation $t\in\mathbb{R}\mapsto\{t\}\times\mathbb{P}^n$, generalizing previous results by Montiel. We also extend a result of Guan and Spruck from hyperbolic ambient space to the general situation of warped products. This extension allows us to give a slightly more general version of a result by Montiel and to derive height estimates for compact constant mean curvature hypersurfaces with boundary in a leaf.
UNITARY PROPAGATION OF OPERATOR DATA
Authors: JabŁoński Zenon J. , Stochel Jan , Szafraniec Franciszek Hugon
Published: January 2008

We study the problem of finding conditions which guarantee that given operator data propagate under the control of unitary operators. This is a kind of moment problem and the way we solve it is based on unitary dilations. Comparing it with other results in this area, our approach has the advantages of

allowing the data to be unbounded operators,

considering arbitrary dilations, not necessarily regular ones.

The relationship between the moment problem and harmonizable multivariate discrete processes is indicated.
Effect of an electric field on the stability of contaminated film flow down an inclined plane
Authors: BLYTH M. G.
Published: January 2008

The stability of a liquid film flowing down an inclined plane is considered when the film is contaminated by an insoluble surfactant and subjected to a uniform normal electric field. The liquid is treated as a perfect conductor and the air above the film is treated as a perfect dielectric. Previous studies have shown that, when acting in isolation, surfactant has a stabilizing influence on the flow while an electric field has a destabilizing influence. The competition between these two effects is the focus of the present study. The linear stability problem is formulated and solved at arbitrary parameter values. An extended form of Squire's theorem is presented to argue that attention may be confined to two-dimensional disturbances. The stability characteristics for Stokes flow are described exactly; the growth rates of the normal modes at finite Reynolds number are computed numerically. We plot the neutral curves dividing regions of stability and instability, and trace how the topology of the curves changes as the intensity of the electric field varies both for a clean and for a contaminated film. With a sufficiently strong electric field, the neutral curve for a clean film consists of a lower branch trapping an area of stable modes around the origin, and an upper branch above which the flow is stable. With surfactant present, a similar situation obtains, but with an additional island of stable modes disjoint from the upper and lower branches.
Impacts on the TRMM data due to orbit boost in the spectral domain
Authors: Cho Hye‐Kyung , Chun Hye‐Yeong
Published: January 2008

The Tropical Rainfall Measuring Mission (TRMM) was extended by the boost to a higher altitude in August, 2001 to gain further benefits in operational weather forecasting and climate research. To establish the credibility of TRMM data, it is necessary to analyze the impacts of orbit boost on TRMM rainfall data retrieval. In this study, the orbital boost's effects are investigated in the spectral domain by comparison with other data sets not affected by boost. The TRMM boost introduces spurious spectral biases differences between pre‐ and post‐boost periods and the independent sampling error study is used to ascertain them. The boost effects are usually exposed as small‐scale, high‐frequency wave signals in TRMM infrared radiation (IR) and microwave imager (TMI) data sets, whereas the spurious spectral differences between the two periods are not as clear in TRMM precipitation radar (PR) data due to the small sampling.
Clinical relevance of TLR2, TLR4, CD14 and FcγRIIA gene polymorphisms in Streptococcus pneumoniae infection
Authors: Yuan Fang Fang , Marks Katherine , Wong Melanie , Watson Sarah , de Leon Ellen , McIntyre Peter Bruce , Sullivan John Stephen
Published: January 2008

Streptococcus pneumoniae is the most common cause of community‐acquired pneumonia and a major cause of morbidity and mortality throughout the world. It has been a major research priority to identify gene polymorphisms responsible for/associated with susceptibility and severity of S. pneumoniae infection to gain a better understanding of host genetic variants and their influence and clinical relevance to pneumococcal infections. In the present study, polymorphisms in several candidate genes, including TLR2‐Arg/Gln753, TLR4‐Asp/Gly299, TLR4‐Thr/Ile399, CD14‐159C/T and FcγRIIA‐R/H131, were examined in 85 children with pneumococcal sepsis as an invasive pneumococcal disease and 409 healthy blood donors as controls. The prevalence of the TLR4‐299/399 polymorphisms was significantly lower in the patient population than in controls (4 vs 11%; P<0.05; odds ratio (OR) 0.3; 95% confidence interval (CI) 0.1–1), while the prevalence of the CD14‐159CC and FcγRIIA‐R/R131 genotypes was significantly higher (35 vs 25%; P<0.05; OR 1.7; 95% CI 1–2.8 and 39 vs 21%; P<0.001; OR 2.5; 95% CI 1.4–4, respectively). Further, only 35% of patients carried either low‐risk genotypes or protective genotypes in contrast to 61% of controls (P<0.0001; OR 2.8; 95% CI 1.7–4.6). We conclude that genetic variability in the TLR4, CD14 and FcγRIIA genes is associated with an increased risk of developing invasive disease in patients who are infected with S. pneumoniae.
An analytical study of the interplay between geometrical and energetic effects in protein folding
Authors: Suzuki Yoko , Noel Jeff K. , Onuchic José N.
Published: January 2008

Analytical studies have several advantages for an understanding of the mechanisms of protein folding such as the interplay between geometrical and energetic effects. In this paper, we introduce a Gaussian filament with a Cα structure-based (Gō) potential as a new theoretical scheme based on a Hamiltonian approach. This model takes into account geometrical information in a realistic fashion without the need of phenomenological descriptions. In order to make this model more appropriate for comparison with protein folding simulations and experiments, we introduce a many-body interaction into the potential term to enhance cooperativity. We apply our new analytical model to a β-hairpin-type peptide and compare our results with a molecular dynamics simulation of a structure-based model.
Influence of phase transformation on the low temperature dielectric measurements in 1-cyanoadamantane
Authors: Carpentier L. , Decressain R. , Descamps M.
Published: January 2008

Dielectric measurements have been performed on the supercooled plastic crystal phase of cyanoadamantane under isothermal and isochronal conditions in the temperature range [170–250K], each experiment with a new sample. The measurements performed in the course of isotherms allowed us to emphasize the effects of the transformations close to the glass transition temperature leading to a change in the dynamic behavior of the compound. The temperature dependence of the dielectric relaxation times exhibits an Arrhenius evolution on the whole metastable domain and gives at the calorimetric glass transition temperature a value of 1s, i.e., two orders of magnitude lower than the usual value [τ(Tg)≅100s]. These results indicate that the Vogel-Fulcher-Tammann behavior observed with other techniques does not appear in the Brillouin zone center (q=0) and that the glass transition for this glass former is not associated with the freezing out of the tumbling motion of individual molecular dipoles but to the freezing out of fluctuations of an antiferroelectric local ordering.
Anomaly Cancellation Launches Superstring Bandwagon
Authors: Schwarzschild Bertram
Published: January 2008

In the last few months it's been difficult to find a particle-theory preprint that doesn't begin with: “Considerable interest in 10-dimensional unified superstring theories has been sparked by the recent discovery of Green and Schwarz that such theories are free of anomalies and, very likely, finite, if the gauge group is SO(32) or E8×E8”—or words to that effect. “Superstring theory is the only plausible approach to quantum gravity anyone has ever come up with,” asserts Edward Witten (Princeton). “But until Green and Schwarz found the generalized anomaly cancellation, it was still conceivable that this beautiful structure had little to do with reality. Now,” Witten contends, “such skepticism has become hard to justify.”
Competition between supercluster and stuffed cage structures in medium-sized Gen (n=30–39) clusters
Authors: Wang Lu , Zhao Jijun
Published: January 2008

We have performed an unbiased global search for the geometries of low-lying Gen clusters in the size range of 30⩽n⩽39 using genetic algorithm incorporated with a tight-binding model. Density functional theory calculations were carried out to further optimize the isomer structures. Gen (n=30–39) clusters prefer the motif of supercluster structures stacked by several stable subunits such as Ge10 and Ge6, connecting via a few bridging atoms. Size-dependent cluster properties such as binding energy, HOMO-LUMO gaps, and ionization potentials were discussed and compared with experiments.
Melt dispersion versus diffusive oxidation mechanism for aluminum nanoparticles: Critical experiments and controlling parameters
Authors: Levitas Valery I. , Pantoya Michelle L. , Dikici Birce
Published: January 2008

Critical experiments were performed on Al and MoO3 thermites. The diameter and alumina shell thickness of the Al nanoparticles were varied, and flame propagation velocities were measured. The results strongly support the melt-dispersion mechanism and contradict the diffusion oxidation mechanism. The parameters that control the oxidation rate and flame velocity are justified and directions for the synthesis of Al nanoparticles (which are opposite to the current directions based on diffusion oxidation) are suggested. An equation for the flame velocity versus Al nanoparticle geometrical parameters, thermomechanical properties, and synthesis parameters is formulated.
Anomalous microwave heating effects in Ce-doped La0.7Sr0.3MnO3: Possible role of grain boundary capacitative effects across cerium solubility limit
Authors: Kale S. N. , Mona J. , Lofland S. E. , Kulkarni S. D. , Ogale S. B.
Published: January 2008

Ce-doped manganite bulk nanocompacts [La0.7−xCexSr0.3MnO3 (0<x<0.1)] are studied for their microwave heating properties at 2.45GHz. The heating effect is found to be nonmonotonic as a function of cerium concentration, and anomalously large heating (burning) is observed for a small concentration window near x=0.03. The x-ray diffraction studies show signatures of CeO2 phase in x>0.03 samples. The various characterizations collectively point to the key role of the developing grain boundary CeO2 layer which leads to highest capacitative intergrain-coupling and related charging-discharging effects when it is thinnest near the apparent Ce solubility limit of x~0.03.
Spectral gap of shear Alfvén waves in a periodic array of magnetic mirrors
Authors: Zhang Yang , Heidbrink W. W. , Boehmer H. , McWilliams R. , Chen Guangye , Breizman B. N. , Vincena S. , Carter T. , Leneman D. , Gekelman W. , Pribyl P. , Brugman B.
Published: January 2008

A multiple magnetic mirror array is formed at the Large Plasma Device (LAPD) [W. Gekelman, H. Pfister, Z. Lucky, J. Bamber, D. Leneman, and J. Maggs, Rev. Sci. Instrum. 62, 2875 (1991)] to study axial periodicity-influenced Alfvén spectra. Shear Alfvén waves (SAW) are launched by antennas inserted in the LAPD plasma and diagnosed by B-dot probes at many axial locations. Alfvén wave spectral gaps and continua are formed similar to wave propagation in other periodic media due to the Bragg effect. The measured width of the propagation gap increases with the modulation amplitude as predicted by the solutions to Mathieu’s equation. A two-dimensional finite-difference code modeling SAW in a mirror array configuration shows similar spectral features. Machine end-reflection conditions and damping mechanisms including electron-ion Coulomb collision and electron Landau damping are important for simulation.
Self-assembled monolayers of protonated poly(amidoamine) dendrimers on indium tin oxide
Authors: Latini Gianluca , Wykes Michael , Schlapak Robert , Howorka Stefan , Cacialli Franco
Published: January 2008

We have investigated the change of work function of indium tin oxide (ITO) anodes induced by adsorption of positively charged poly(amidoamine) (PAMAM) dendrimers. Kelvin probe characterization of the functionalized ITO films and electroabsorption measurements on polymer light-emitting diodes incorporating poly(9,9-dioctylfluorene) active layers revealed an abrupt (0.55eV) lowering of the effective work function upon addition of the adsorbed layer and a weak dependence on the PAMAM generation. We interpret our results with an electrostatic model accounting for both positively charged amines and for possible contaminations providing compensating negative charges.
Memory characteristics of cobalt-silicide nanocrystals embedded in HfO2 gate oxide for nonvolatile nanocrystal flash devices
Authors: Kim JooHyung , Yang JungYup , Lee JunSeok , Hong JinPyo
Published: January 2008

Cobalt-silicide (CoSi2) nanocrystals (NCs) were investigated for use in charge storage for metal oxide semiconductor (MOS) devices with thin HfO2 tunneling and control oxide layers. CoSi2 NCs were synthesized by exposure of Co∕Si∕HfO2 tunneling oxide/Si stacks to an external UV laser. Observations from transmission electron microscopy and x-ray photoelectron spectroscopy clearly confirm the formation of CoSi2 NCs and the values of Co–Si bonding energies that are shifted 0.3eV from original values, respectively. The CoSi2 NCs in MOS devices exhibited a large memory window of 3.4V as well as efficient programming/erasing speeds, good retention, and endurance times.
Radionuclide Releases from Severe Accidents at Nuclear Power Plants
Authors: Levi Barbara G.
Published: January 2008

Regulations governing siting and evacuation procedures for a nuclear power plant rely heavily on estimates of the quantities and types of radioactive fission products that might be emitted in the most severe accident. These estimates are called source terms. The most conservative approach to analyzing accident consequences is to assume that a severe accident might release the entire inventory of fission products within the core just before refueling. Most current regulations rely on a slight modification of that source term—100% of the noble gases, 50% of the iodine and 1% of the remaining fission products. Recent emergency procedures are based on lower, although still conservative, estimates of iodine releases.
Strategic Defense Initiative: The Politics and Science of Weapons in Space
Authors: Yonas Gerold
Published: January 2008

On 23 March 1983, President Reagan announced on national television that he was “launching an effort which holds the promise of changing the course of human history”—a scientific research program to determine whether a defense against ballistic missiles could be feasible. The President characterized the program, now known as the Strategic Defense Initiative, as a “formidable technical task” that might not be attainable before the end of this century. “Would it not be better to save lives than to avenge them?” he asked that night. “What if free people could live secure in the knowledge that their security did not rest upon the threat of instant retaliation to deter a Soviet attack, that we could intercept and destroy strategic ballistic missiles before they reach our soil or that of our allies?” At the end of his talk, he called on the scientific community that invented nuclear weapons “to turn their great talents now to the cause of mankind and world peace, to give us the means” to devise ways of “rendering nuclear weapons impotent and obsolete.”
Math Anxiety and Physics: Some Thoughts on Learning ‘Difficult’ Subjects
Authors: Tobias Sheila
Published: January 2008

For some time now, teachers of physics concerned about the growing gap between the Two Cultures have been, so to speak, stalking the wild humanist. They have set up courses in “physics for poets,” recruited nonscience students into seminars to “ready” them for science, and offered physics without the laboratory or calculus. Yet, despite these and other efforts to attract them, liberal-arts majors continue to find ways to avoid physics, even when fulfilling minimum science requirements.
Perspectives on the Presidency of the American Physical Society
Authors: Dresselhaus Mildred S.
Published: January 2008

It may seem surprising that the most frequent question I was asked during the year I served as president of The American Physical Society was “how it felt” to be president of this distinguished and venerable society. This question is perhaps not so surprising when you consider that the probability for a physicist to experience personally this challenge is only on the order of one chance in a thousand. In this article I will attempt to give one operational answer to this complex question.