bluuebunny/crossref_metadata_2025 huggingface dataset:
1H{19F} NOE NMR Structural Signatures of the Insulin R6Hexamer: Evidence of a Capped HisB10 Site in Aryl‐ and Arylacryloyl‐carboxylate Complexes
Authors: Keidel Donald , Bonaccio Maria , Ghaderi Nima , Niks Dimitri , Borchardt Dan , Dunn Michael F.
Published: January 2009

New and improved insulin:1H{19F} NOE NMR difference spectra for CF3‐substituted aromatic carboxylates bound at the HisB10 sites of the R6human insulin (HI) hexamer show strong NOEs between the CF3groups and the LeuB6, AsnB3, and PheB1 sidechains. The NOEs and structural modeling establish that these carboxylates form closed complexes with the HisB10 site capped by the PheB1 rings.

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Design, Synthesis, and Biological Evaluation of Enantiomeric β‐N‐Acetylhexosaminidase Inhibitors LABNAc and DABNAc as Potential Agents against Tay‐Sachs and Sandhoff Disease
Authors: Rountree J. S. Shane , Butters Terry D. , Wormald Mark R. , Boomkamp Stephanie D. , Dwek Raymond A. , Asano Naoki , Ikeda Kyoko , Evinson Emma L. , Nash Robert J. , Fleet George W. J.
Published: January 2009

Combating glycolipid storage disorders: LABNAc was prepared in an efficient 11‐step procedure from D‐lyxonolactone. The enantiomer DABNAc was also prepared from L‐lyxonolactone. Preliminary cellular studies indicate that these compounds may find utility as chemical chaperones for the treatment of Tay‐Sachs and Sandhoff diseases.

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N‐Acetylhexosaminidases are of considerable importance in mammals and are involved in various significant biological processes. In humans, deficiencies of these enzymes in the lysosome, resulting from inherited genetic defects, cause the glycolipid storage disorders Tay‐Sachs and Sandhoff diseases. One promising therapy for these diseases involves the use of β‐N‐acetylhexosaminidase inhibitors as chemical chaperones to enhance the enzyme activity above sub‐critical levels. Herein we describe the synthesis and biological evaluation of a potent inhibitor, 2‐acetamido‐1,4‐imino‐1,2,4‐trideoxy‐L‐arabinitol (LABNAc), in a high‐yielding 11‐step procedure from D‐lyxonolactone. The N‐benzyl and N‐butyl analogues were also prepared and found to be potent inhibitors. The enantiomers DABNAc and NBn‐DABNAc were synthesised from L‐lyxonolactone, and were also evaluated. The L‐iminosugar LABNAc and its derivatives were found to be potent noncompetitive inhibitors of some β‐N‐acetylhexosaminidases, while the D‐iminosugar DABNAc and its derivatives were found to be weaker competitive inhibitors. These results support previous work postulating that D‐iminosugar mimics inhibit D‐glycohydrolases competitively, and that their corresponding L‐enantiomers show noncompetitive inhibition of these enzymes. Molecular modelling studies confirm that the spatial organisation in enantiomeric inhibitors leads to a different overlay with the monosaccharide substrate. Initial cell‐based studies suggest that NBn‐LABNAc can act as a chemical chaperone to enhance the deficient enzyme's activity to levels that may cause a positive pharmacological effect. LABNAc, NBn‐LABNAc, and NBu‐LABNAc are potent and selective inhibitors of β‐N‐acetylhexosaminidase and may be useful as therapeutic agents for treating adult Tay‐Sachs and Sandhoff diseases.
Early lead exposure effects on an auditory threshold task in the rhesus monkey (Macaca mulatta)
Authors: Laughlin Nellie K. , Luck Melissa L. , Lasky Robert E.
Published: January 2009

Behavioral thresholds to pure tones were obtained from adult rhesus monkeys that had been exposed to lead during early development and unexposed cohort controls. Thresholds were elevated (by 2–9 dB) for the previously lead exposed monkeys at all frequencies tested (125–8,000 Hz in octave steps). Although the magnitude and direction of the differences were similar to significant effects reported for children, the more difficult task and much smaller sample sizes in this study of monkeys may have precluded obtaining significant differences at the same magnitude of effects observed in children. Thresholds for one lead‐exposed monkey were significantly elevated at midrange frequencies in agreement with electrophysiological results obtained in another study [Lasky, Maier, Snodgrass, Hecox, and Laughlin [1995] Neurotoxicology and Teratology, 17, 633–644]. Behavioral measurements during the threshold task indicated less engagement for lead exposed monkeys than for controls. In addition, the lead exposed monkeys completed testing at significantly fewer frequencies and were significantly more difficult to test than control monkeys by tester ratings. These results are consistent with reports concerning the behavior of lead exposed children. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 289–300, 2009
Insulin analogues display IGF‐I‐like mitogenic and anti‐apoptotic activities in cultured cancer cells
Authors: Weinstein Doron , Simon Meital , Yehezkel Einat , Laron Zvi , Werner Haim
Published: January 2009

Background

Insulin analogues are widely used in the treatment of diabetes mellitus. Some insulin analogues were reported to display atypical activities in vitro that resemble those of insulin‐like growth factor‐I (IGF‐I). The aim of this study was to investigate whether two long‐acting insulin analogues [glargine (Lantus, Sanofi Aventis, Germany) and detemir (Levemir, Novo Nordisk, Denmark)] and two short‐acting analogues [lispro (Humalog, Eli Lilly, Indianapolis, USA) and aspart (Novolog, Novo Nordisk, Denmark)] exhibit IGF‐I‐like activities on cultured cancer cells in comparison with IGF‐I and regular human insulin.

Methods

HCT‐116 (colorectal cancer), PC‐3 (prostate cancer) and MCF‐7 (breast adenocarcinoma) cell lines were treated with insulin, IGF‐I or insulin analogues, and proliferation and protection from apoptosis were measured by cell counting and fluorescent‐activated cell sorter (FACS) analysis, respectively. In addition, Western blots were used to identify signalling molecules activated by the analogues.

Results

Glargine, detemir and lispro had proliferative effects that resemble IGF‐I action. Insulin, however, did not stimulate cellular proliferation. In addition, glargine and detemir displayed an IGF‐I‐like anti‐apoptotic activity. Glargine, like insulin and IGF‐I, induced phosphorylation of both ERK and AKT, suggesting that the analogue is able to stimulate both the ras‐raf‐mitogen‐activated protein kinase (MAPK) and PI3K‐AKT pathways. Furthermore, glargine induced both insulin receptor (IR) and IGF‐IR phosphorylation.

Conclusions

Glargine, detemir and lispro, unlike regular insulin, exhibit in vitro proliferative and anti‐apoptotic activities in a number of cancer cell lines. These actions resemble some of the effects of IGF‐I, a growth factor involved in cancer initiation and progression. Insulin had no increased IGF‐I activity. The specific receptor/s involved in mediating analogues actions remains to be identified. Copyright © 2009 John Wiley & Sons, Ltd.
Harmonic characteristics of SC coil configuration for EDS maglev to reduce leakage flux
Authors: Murai Toshiaki , Sakamoto Yasuaki , Fujiwara Shunsuke , Yoshioka Hiroshi
Published: January 2009

An improved configuration of SC coils, whose end coils are small, is studied to reduce their leakage flux. This paper examines the harmonic characteristics when the improved configuration of SC coils is applied to the 120‐degree coil pitch ground coil. An adequate combination of length and mmf in the end coils can provide proper performance of harmonics and basis. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 91(10): 20– 27, 2008; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/ecj.10163
A study of lightning phenomena on distribution lines based on a lightning‐surge analysis model for direct lightning strokes
Authors: Miyazaki Teru , Okabe Shigemitsu , Aiba Kiyoshi , Hirai Takao , Yoshinaga Jun
Published: January 2009

In order to rationalize the lightning protection design of distribution lines, lightning phenomena on TEPCO's distribution lines were continuously observed. The observations were carried out with still cameras and lightning surge monitoring sensors. The results elucidate the lightning performance of distribution lines. For example, direct lightning strokes are the major cause of the present distribution line faults. This fact suggests that it is important to investigate observation data on direct lightning strokes. The observation data were analyzed by means of a direct lightning analysis model. The calculated waveforms were compared with the measured waveforms on distribution lines. The probability distributions of the surge currents and voltages were calculated by the Monte Carlo method. These results provide new data on lightning performance. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 91(10): 28– 37, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10164
Heterometallic Ferrocene‐Rhenium Complexes Linked by an Aminoethylglycine Scaffold
Authors: Levine Lauren A. , Kirin Srećko I. , Myers Carl P. , Showalter Scott A. , Williams Mary Elizabeth
Published: January 2009

Using mono‐ and 1,n′‐disubstituted ferrocenecarboxylic acid, the aminoethylglycine (aeg) derivatives Fe[C5H4‐CO‐aeg‐OtBu][C5H5] (1) and Fe[C5H4‐CO‐aeg‐OtBu]2 (2) have been synthesized. Complexes 1 and 2 are further reacted to substitute the aeg with the nitrogen‐containing ligands dpa‐ph‐CO2H or py‐AcOH to yield complexes 3–6. Each of these is treated with Re(CO)5Cl to assemble heterometallic structures 3Re–6Re. These are subsequently isolated and characterized by NMR and mass spectrometry, FTIR, UV/Vis absorbance, and fluorescence emission spectroscopy, and separately by electrochemistry. All of the compounds exhibit the characteristic redox properties of the ferrocene moiety; in the heterometallic compounds, an irreversible oxidative wave is attributed to the Re. The electrochemically determined diffusion coefficients of the compounds confirm that the as‐prepared structures are discrete assemblies and not coordination polymers.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Ammonia‐Assisted Fabrication of Flowery Nanostructures of Metallic Nickel Assembled from Hexagonal Platelets
Authors: Ni Xiaomin , Zheng Huagui , Yang Qing , Tang Kaibin , Liao Guangxuan
Published: January 2009

A simple one‐pot solution method was reported for the synthesis of metallic nickel nanostructures assembled from hexagonal nanoplatelets. The process involved the reduction of nickelous salt with hydrazine in ammonia solution, and the reaction proceeded without the use of surfactants or external magnetic forces. By properly adjusting the experimental parameters, we realized the anisotropic growth of face‐centered‐cubic (fcc) nickel into hexagonal nanoplatelets and their simultaneous assembly into flowery architectures. The cooperative effects of the ammonia complexing agent, a proper reaction rate, inherent magnetic interactions, and assembly entropy were considered the key factors driving the formation of the special assembly nanostructures on the basis of a series of contrast experiments. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis of Analogues of Acyclic Nucleoside Diphosphates Containing a (Phosphonomethyl)phosphanyl Moiety and Studies of Their Phosphorylation
Authors: Doláková Petra , Dračínský Martin , Fanfrlík Jindřich , Holý Antonín
Published: January 2009

Acyclic nucleoside diphosphonate derivatives of purines and pyrimidines were prepared by Mitsunobu reaction of suitably protected heterocyclic bases with alcohols containing the (phosphonomethyl)phosphanyl moiety. Furthermore, nonhydrolyzable acyclic analogues of dUDP were prepared as potential inhibitors of dUTPase. Their phosphorylation to analogues of dUTP, however, gave mixtures of linear and branched phosphates. The courses of the phosphorylation reactions were followed by 31P NMR spectroscopy, and we discovered that both phosphonate and phosphinate moieties react with 1,1′‐carbonyldiimidazole and tri‐n‐butylammonium phosphate. The pKa values of the (phosphonomethyl)phosphanyl system were also determined by 31P NMR spectroscopy (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
A Bis(m‐phenylene)‐32‐crown‐10/Paraquat [2]Rotaxane
Authors: Li Shijun , Zhu Kelong , Zheng Bo , Wen Xianhong , Li Ning , Huang Feihe
Published: January 2009

The successful preparation of the first bis(m‐phenylene)‐32‐crown‐10/paraquat [2]rotaxane showed unambiguously that psuedorotaxane‐type complexation, rather than the taco‐complex‐type complexation previously observed in the solid state and in solution, exists – in solution – for complexation between bis(m‐phenylene)‐32‐crown‐10 derivatives and paraquat derivatives.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Relationship between Hpt polymorphisms and serum protein electropherogram
Authors: Guerranti Roberto , Bertocci Erica , Muzzi Chiara , Leoncini Roberto , Rossi Stefania , Scapellato Carlo , Pagani Roberto
Published: January 2009

Serum protein electrophoresis is routinely used to identify pathologies involving dysproteinemia. The electropherogram mainly represents the most abundant serum proteins, one of which is the polymorphic haptoglobin (Hpt), characterized by a molecular heterogeneity with three major phenotypes (Hpt 1–1, 2–1, and 2–2). To improve the interpretation of electropherogram and possibly to extend its applicability, we aimed to explore the relationship between Hpt phenotypes (determined by immunoblotting) and protein profiles. Serum samples were separated by CZE with PROTEIN 6 and high‐resolution methods. The PROTEIN 6 analysis showed significant associations between α2 zone profiles and Hpt phenotypes (chi‐square=154.06, p<0.0001). The high‐resolution method indicated significant differences between Hpt 2–2 and Hpt 1–1 peak mobilities, evidenced by receiver operating characteristic analysis, (area under the receiver operating characteristic curve=0.98, p<0.0001, standard error=0.01346, likelihood ratios=21.39), with 98.7% sensitivity, and 95.4% specificity. However, the structural heterogeneity of Hpt 2–1 made it difficult to relate with a particular profile. Thus, we developed an alternative approach that excluded the Hpt 1–1 or Hpt 2–2 phenotypes. This may prove to be a useful technique in clinical applications considering the involvement of Hpt 2–2 or Hpt 1–1 in various pathologies.
Predictors of rapid cognitive decline among demented subjects aged 75 or more: (‘Sujet Agé Fragile—Evaluation et Suivi’ Cohort—SAFES)
Authors: Viatonou Saturnin , Dramé Moustapha , Jolly Damien , Morrone Isabella , Lang Pierre‐Olivier , Voisin Thierry , Boyer François Constant , Schwebel Gautier , Somme Dominique , Blanchard François , Novella Jean‐Luc
Published: January 2009

Objective

To identify factors predictive of rapid cognitive decline (RCD) among elderly subjects aged 75 or over suffering from dementia.

Methods

The analysis concerned 250 patients drawn from the ‘Sujet Agé Fragile – Evaluation et Suivi’ (SAFES) cohort, presenting a dementia syndrome at inclusion and followed‐up for at least 1 year. RCD was defined as the loss of at least 3 points on the Mini‐Mental State Examination (MMSE) in the follow‐up period of 12 months. All patients underwent a standardised geriatric evaluation. Logistic regression was used to identify factors predictive of RCD.

Results

In the study sample, 84 patients (33.6%) presented RCD. The factors identified in multivariate analysis as predictive of RCD were: high level of education (OR = 7.8, 95% CI = [1.9–31.2], p = 0.004), risk of depression (OR = 1.8, 95% CI = [1.02–3.18], p = 0.048, and the initial MMSE score (OR = 1.1, 95% CI = [1.0–1.2], p = 0.002). Among subjects with a main caregiver (n = 177), the predictive factors were malnutrition or risk thereof (OR = 4.2, 95% CI = [1.3–14.1], p = 0.02), risk of a fall (OR = 2.6, 95% CI = [1.1–6.1], p = 0.03, caregiver burden (OR = 2.6, 95% CI = [1.1–6.4], p = 0.04) and initial MMSE score (OR = 1.1, 95% CI = [1.0–1.3], p = 0.004).

Conclusions

As soon as dementia is diagnosed in elderly subjects, information should be collected about the subject's socioeconomic status, nutritional status, risk of falling, mood state, and caregiver burden. This would enable the provision of appropriate therapeutic care, and make it possible to adapt follow‐up in case of a risk of accelerated cognitive deterioration. Copyright © 2009 John Wiley & Sons, Ltd.
Posttraumatic stress disorder in older people after a fall
Authors: Chung Man Cheung , McKee Kevin J. , Austin Chris , Barkby Helen , Brown Hayley , Cash Sophie , Ellingford Jenny , Hanger Liz , Pais Tara
Published: January 2009

Background

Posttraumatic Stress Disorder (PTSD) is a debilitating psychological condition, never studied in relation to falls in older people. This study determines the prevalence and correlates of PTSD in older people post‐fall.

Method

A prospective survey study, with baseline data collected by interview in hospital post‐fall and by postal self‐completion at 12 and 24 weeks post‐baseline. A convenience sample of 196 people (≥ 65 years) were serially recruited, 87.9% of those eligible. Information collected at baseline included falls‐related data, activity problems, fear of falling, PTSD symptoms, anxiety and depression, and at follow‐up PTSD symptoms, anxiety and depression, the receipt of rehabilitation and further falls.

Results

In hospital, of 40 participants whose fall had occurred over 1 month previously 35% had full acute PTSD and 17.5% had partial acute PTSD. At follow‐up full or partial chronic PTSD was found in 26.1% of participants at first follow‐up, and in 27.4% of participants at second follow‐up. Older age, pre‐fall activity problems, fear of falling, and anxiety assessed at baseline were associated (p < 0.05) with follow‐up PTSD diagnosis, as were anxiety and depression assessed concurrently.

Conclusion

PTSD occurs in a substantial minority of older people post‐fall. No pattern emerged of factors predictive of PTSD, although the association between fear of falling and PTSD suggests some patients thought to have fear of falling may be manifesting PTSD, and require identification to enable therapeutic intervention. Copyright © 2009 John Wiley & Sons, Ltd.
Comfort evaluation and bed adjustment according to sleeping positions
Authors: Park Se Jin , Kim Jin Sun , Kim Chae‐Bogk
Published: January 2009

This study explodes the relationships between the height adjustment of bed sectors and subjective comfort depending on three types of sleeping positions. An adjustable bed system that regulates the heights of 8 adjustment sectors of the bed was developed. To evaluate the comfort of 9 body areas, subjective ratings were requested from 64 subjects ranging in age from 25 to 50. The subjects included 29 males and 35 females. For an objective evaluation, the patterns of pressure distribution were investigated according to the three sleeping positions. During two separate states (before bed adjustment and after bed adjustment), measurements of the adjusted bed height and pressure distribution, and subjective ratings according to three sleeping positions were performed. Based on the results of the adjusted heights of the 8 sectors in the bed, the subjects preferred the W‐shaped sleeping posture in both the supine and side positions. However, the U‐shaped sleeping posture was preferred in the prone position. With respect to these sleeping positions, the heights of sectors significantly correlated with the subjective ratings presented by the subjects, as well as the ratios of pressure. © 2009 Wiley Periodicals, Inc.
Hydroclimatic influence of large‐scale circulation on the variability of reservoir inflow
Authors: Maity Rajib , Nagesh Kumar D.
Published: January 2009

In this study, the nature of basin‐scale hydroclimatic association for Indian subcontinent is investigated. It is found that, the large‐scale circulation information from Indian Ocean is also equally important in addition to the El Niño‐Southern Oscillation (ENSO), owing to the geographical location of Indian subcontinent. The hydroclimatic association of the variation of monsoon inflow into the Hirakud reservoir in India is investigated using ENSO and EQUatorial INdian Ocean Oscillation (EQUINOO, the atmospheric part of Indian Ocean Dipole mode) as the large‐scale circulation information from tropical Pacific Ocean and Indian Ocean regions respectively. Individual associations of ENSO & EQUINOO indices with inflow into Hirakud reservoir are also assessed and found to be weak. However, the association of inflows into Hirakud reservoir with the composite index (CI) of ENSO and EQUINOO is quite strong. Thus, the large‐scale circulation information from Indian Ocean is also important apart form the ENSO. The potential of the combined information of ENSO and EQUINOO for predicting the inflows during monsoon is also investigated with promising results. The results of this study will be helpful to water resources managers due to fact that the nature of monsoon inflow is becoming available as an early prediction. Copyright © 2009 John Wiley & Sons, Ltd.
Hyporheic exchange flow around constructed in‐channel structures and implications for restoration design
Authors: Crispell Jill K. , Endreny Theodore A.
Published: January 2009

In‐channel rock vane structures are widely used in stream restoration as a way to reduce stream channel erosion and create pool or riffle features. When these structures change hydraulic gradients they may affect ecological stream functions, such as hyporheic exchange flow (HEF) patterns. A study of constructed in‐channel structure controls on HEF was conducted in the third‐order Batavia Kill, New York using stream and hyporheic temperature amplitude analysis and computational fluid dynamics (CFD) hydraulic simulations. Temperature monitors were installed in the water column and channel bed at six locations around each of seven in‐channel restoration structures (three cross‐vanes and four J‐hooks) at baseflow in 2007. Elevation surveys of the structures were then used to simulate HEF using CFD. The results indicate a pattern of pronounced upwelling in the run section just below the structure, upwelling transitioning to downwelling within the pool, and pronounced downwelling in the glide out of the pool. This pattern is consistent with natural riffle pool sequences. The direction of HEF inferred from the temperature amplitude analysis agreed with the direction of flow simulated with CFD at 80% of the locations, and the few disagreements were expected due to model limitations. CFD simulation demonstrated that increasing stream flows result in changes in HEF spatial patterns and magnitude at each structure. This work illustrates how CFD simulations can guide design of in‐channel restoration structures for HEF function. Copyright © 2009 John Wiley & Sons, Ltd.
Sensitivity analysis of prior model probabilities and the value of prior knowledge in the assessment of conceptual model uncertainty in groundwater modelling
Authors: Rojas Rodrigo , Feyen Luc , Dassargues Alain
Published: January 2009

A key point in the application of multi‐model Bayesian averaging techniques to assess the predictive uncertainty in groundwater modelling applications is the definition of prior model probabilities, which reflect the prior perception about the plausibility of alternative models. In this work the influence of prior knowledge and prior model probabilities on posterior model probabilities, multi‐model predictions, and conceptual model uncertainty estimations is analysed. The sensitivity to prior model probabilities is assessed using an extensive numerical analysis in which the prior probability space of a set of plausible conceptualizations is discretized to obtain a large ensemble of possible combinations of prior model probabilities. Additionally, the value of prior knowledge about alternative models in reducing conceptual model uncertainty is assessed by considering three example knowledge states, expressed as quantitative relations among the alternative models. A constrained maximum entropy approach is used to find the set of prior model probabilities that correspond to the different prior knowledge states. For illustrative purposes, a three‐dimensional hypothetical setup approximated by seven alternative conceptual models is employed. Results show that posterior model probabilities, leading moments of the predictive distributions and estimations of conceptual model uncertainty are very sensitive to prior model probabilities, indicating the relevance of selecting proper prior probabilities. Additionally, including proper prior knowledge improves the predictive performance of the multi‐model approach, expressed by reductions of the multi‐model prediction variances by up to 60% compared with a non‐informative case. However, the ratio between‐model to total variance does not substantially decrease. This suggests that the contribution of conceptual model uncertainty to the total variance cannot be further reduced based only on prior knowledge about the plausibility of alternative models. These results advocate including proper prior knowledge about alternative conceptualizations in combination with extra conditioning data to further reduce conceptual model uncertainty in groundwater modelling predictions. Copyright © 2009 John Wiley & Sons, Ltd.
Comparative hydrology: analysis of a semiarid and a humid tropical watershed
Authors: de Araújo José Carlos , González Piedra Julio Iván
Published: January 2009

This paper analyses measured data from two small tropical watersheds: one in a semiarid (Aiuaba, Brazil, 12·0 km2, 5 years of measurements) and another in a humid environment (Jaruco, Cuba, 43·5 km2, 21 years of measurements). The watersheds are similar with respect to catchment area (tens of km2), potential evaporation (2·1–2·6 m year−1), temperature (22–30 °C) and relief (mild hillslope steepness); but show considerable hydrological discrepancies: average precipitation in the humid watershed is two times higher; average river discharge (mm year−1) is five times higher; and surface water availability (mm year−1) is 14 times higher than in the semiarid watershed. Long‐term operation of hypothetical surface reservoirs in both basins is simulated. The analysis shows that 73% of the average river discharge are available (with 90% annual reliability) in the humid watershed, against only 28% in the semiarid. The main cause of this difference is the excess evaporation, which consumes 55% of the stored water in the semiarid reservoir, but only 12% in the humid one. The research concludes that: (1) although precipitation indicators are higher in the humid area, they are of the same order of magnitude as in the semiarid; and (2) fluvial‐regime and water‐availability variables are more than one order of magnitude higher in the humid basin, which shows a multiplication effect of these hydrological processes. Such major hydrological differences, despite the similarities between the two tropical watersheds, show the importance of further investigations in the field of comparative hydrology. Copyright © 2009 John Wiley & Sons, Ltd.
Enhancement of antibiotic elution from acrylic bone cement
Authors: Anagnostakos Konstantinos , Kelm Jens
Published: January 2009

Antibiotic‐loaded acrylic bone cement is a well‐established tool in the prophylaxis and treatment of orthopedic infections. Numerous studies about its pharmacokinetic properties have demonstrated that only a small part of the incorporated antibiotic amounts can be released, mostly over the first 8–10 weeks. Therefore, in the past 10 years, several attempts have been made for enhancement of the drug elution from bone cement. This article reviews this experience and pays special attention on biantibiotic combinations, additives other than antimicrobial agents, as well as the effect of ultrasound on the antibiotic elution characteristics. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Fabrication of freeform bone‐filling calcium phosphate ceramics by gypsum 3D printing method
Authors: Lowmunkong Rungnapa , Sohmura Taiji , Suzuki Yumiko , Matsuya Shigeki , Ishikawa Kunio
Published: January 2009

Transformation of gypsum model fabricated by three‐dimensional printing (3DP) into hydroxyapatite (HA) by treating in ammonium phosphate solution is possible. However, 3DP powder supplied by the manufacturer contains unknown additives which may be questionable for biomaterials. Accordingly, pure plaster of Paris (POP) powder was used for fabrication in the present study. For accurate fabrication, reduction of supplied binder ink to 80% of standard amount for 3DP powder supplied by the manufacturer was found to be the optimal condition for POP fabrication. Transformation from POP to HA was done by immersing into 1 mol/L ammonium phosphate solution. However, preheating of fabricated POP specimen at 200°C for 30 min to change from calcium sulfate dihydrate into calcium sulfate hemihydrate could accelerate the transformation into HA effectively. To increase compressive strength, HA transformed specimen was sintering at 1150°C for 3 h. The compressive strength increased four times comparing with as transformed HA specimen. However, crystal structure was transformed to β‐TCP due to the chemical reaction between the transformed HA and remained phosphate from ammonium phosphate solution at the sintering temperature. A sophisticated application of the present 3DP method to fabricate the freeform bioceramic for osseous defect was attempted, and jaw bone defect filling biomaterial of β‐TCP and scaffold with macroporous structures could be fabricated. Present 3DP method has possibility to fabricate freeform bioceramic for osseous defect or scaffold. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
The credibility issue: closing the academic/practitioner gap
Authors: Hughes Tim , O'Regan Nicholas , Wornham David
Published: January 2009

The literature is highly critical of the business–academia relationship and there is a lack of congruence between strategic management research conducted by academics and that used by practitioners. There is also a lack of models of collaborative research and its dissemination.

This research aims to identify means by which the degree of academia versus business congruence can be enhanced in managing strategic change effectively.

A critical realist approach was taken using semi‐structured interviews with practitioners, academics, and consultants in order to get a balance of views from different perspectives.

The interviewees presented an opaque picture with a lack of clarity as to how organizations might or should access strategy thinking from within academia. This also extends to some uncertainty about what industry ‘needs’ and, from the point of view of the academic, what should be provided to client organizations.

The results indicate that the transfer of new strategy approaches can only be achieved once practitioners acknowledge the credibility of academia in contributing to practitioner‐related issues.

Analysis of the qualitative data collected for this project suggests that achieving practitioner credibility requires the context and content of collaborations to be more proactively managed through more effective processes.

Implications for academic institutions as well as individual strategic management academics are discussed.

Copyright © 2008 John Wiley & Sons, Ltd.
Organizational change in the National Health Service: lessons from the staff
Authors: Marshall Joe , Olphert Anne‐Maria
Published: January 2009

This paper is based on research on the impact organizational change (mergers) had upon staff and patient care in Primary Care Trusts (PCTs) within Leicester, Leicestershire, and Rutland from 2006 to 2007.

The latest round of health reform has been driven by the ‘Commissioning a Patient‐Led NHS’ (CaPLNHS; DOH, 2005) plan to reduce the number of PCTs and for a saving of £250 million in administrative and management costs.

A cross‐sectional case study using a series of focus groups was undertaken to identify salient aspects of mergers and organizational change in a health sector context and explore staff perceptions (negative and positive) of the recent organizational wide changes. Based on the findings, we propose an ‘Agenda for Action’ to recognize and minimize the potential negative effects upon staff and service delivery.

Copyright © 2008 John Wiley & Sons, Ltd.
Using the GRAPPA operator and the generalized sampling theorem to reconstruct undersampled non‐Cartesian data
Authors: Seiberlich Nicole , Breuer Felix A. , Ehses Philipp , Moriguchi Hisamoto , Blaimer Martin , Jakob Peter M. , Griswold Mark A.
Published: January 2009

As expected from the generalized sampling theorem of Papoulis, the use of a bunched sampling acquisition scheme in conjunction with a conjugate gradient (CG) reconstruction algorithm can decrease scan time by reducing the number of phase‐encoding lines needed to generate an unaliased image at a given resolution. However, the acquisition of such bunched data requires both modified pulse sequences and high gradient performance. A novel method of generating the “bunched” data using self‐calibrating GRAPPA operator gridding (GROG), a parallel imaging method that shifts data points by small distances in k‐space (with Δk usually less than 1.0, depending on the receiver coil) using the GRAPPA operator, is presented here. With the CG reconstruction method, these additional “bunched” points can then be used to reconstruct an image with reduced artifacts from undersampled data. This method is referred to as GROG‐facilitated bunched phase encoding (BPE), or GROG‐BPE. To better understand how the patterns of bunched points, maximal blip size, and number of bunched points affect the reconstruction quality, a number of simulations were performed using the GROG‐BPE approach. Finally, to demonstrate that this method can be combined with a variety of trajectories, examples of images with reduced artifacts reconstructed from undersampled in vivo radial, spiral, and rosette data are shown. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Diltiazem and verapamil protect dystrophin‐deficient muscle fibers of MDX mice from degeneration: A potential role in calcium buffering and sarcolemmal stability
Authors: Matsumura Cintia Yuri , Pertille Adriana , Albuquerque Tereza C.P. , Santo Neto Humberto , Marques Maria Julia
Published: January 2009

The lack of dystrophin in mdx mice and in Duchenne muscular dystrophy causes sarcolemmal breakdown and increased calcium influx followed by myonecrosis. We examined whether the calcium channel blockers diltiazem and verapamil protect dystrophic muscles from degeneration. Mdx mice received daily intraperitoneal injections of diltiazem or verapamil for 18 days, followed by removal of the sternomastoid, diaphragm, tibialis anterior, and cardiac muscles. Control mdx mice were injected with saline. Both drugs significantly decreased blood creatine kinase levels. Total calcium content was significantly higher in mdx muscles than in control C57Bl/10. Verapamil and diltiazem reduced total calcium content only in diaphragm and cardiac muscle. Histological analysis showed that diltiazem significantly attenuated myonecrosis in diaphragm. Immunoblots showed a significant increase of calsequestrin and β‐dystroglycan levels in some diltiazem‐ and verapamil‐treated muscles. Possible interactions of these drugs with the sarcoplasmic reticulum and sarcolemma may also contribute to the improvement of the dystrophic phenotype. Muscle Nerve 39: 167–176, 2009
Frontal plane ankle proprioceptive thresholds and unipedal balance
Authors: Son Jaebum , Ashton‐Miller James A. , Richardson James K.
Published: January 2009

Reliable unipedal balance is fundamental to safe ambulation. Accordingly, older persons with peripheral neuropathy (PN), who are at increased risk for falls, demonstrate impaired unipedal balance. To explore the relationship between afferent function and unipedal balance, frontal plane proprioceptive thresholds at the ankle were quantified in 22 subjects (72.5 ± 6.3 years; 11 with PN and 11 matched controls) while they were standing using a foot cradle system and a staircase series of 100 rotational stimuli. PN subjects, as compared to controls, demonstrated shorter median unipedal balance times (3.4 ± 2.7 vs. 14.3 ± 8.9 s; P = 0.0017) and greater (less precise) combined ankle inversion/eversion proprioceptive thresholds (1.17 ± 0.36 vs. 0.65 ± 0.37°; P = 0.0055). Combined ankle inversion/eversion proprioceptive thresholds explained approximately half the variance in unipedal balance time (R2 = 0.5138; P = 0.0004). Given prior work demonstrating a similarly strong relationship between ankle torque generation and unipedal balance, neuropathy‐associated impairments in ankle frontal plane afferent and efferent function appear to be equally responsible for the inability of older persons with PN to reliably balance on one foot. They therefore provide distinct targets for intervention. Muscle Nerve 39: 150–157, 2009
Passive properties of the muscle‐tendon unit: The influence of muscle cross‐sectional area
Authors: Ryan Eric D. , Herda Trent J. , Costa Pablo B. , Defreitas Jason M. , Beck Travis W. , Stout Jeffrey R. , Cramer Joel T.
Published: January 2009

The purpose of the present study was to examine the relationships among the passive properties of the muscle–tendon unit and muscle cross‐sectional area (CSA). Our findings indicated significant relationships between muscle CSA and passive stiffness (P < 0.05; r = 0.830) and muscle CSA and passive energy absorption (P < 0.05; r = 0.765). Since passive stiffness and the ability to absorb passive energy decreases with many diseases, these findings may support the need to maintain or increase muscle CSA. Muscle Nerve 39: 227–229, 2009
Magnitude of QT prolongation associated with a higher risk of Torsades de Pointes
Authors: Lin Yeong‐Liang , Kung Mei‐Fen
Published: January 2009

Purpose

Drug induced Torsades de Pointes (TdP) is a major concern for new drugs seeking regulatory approval. Prolongation of QT intervals greater than 60 millisecond or to longer than 500 millisecond in an individual patient has been considered to be associated with a higher risk. The purpose of this study is to identify values inferred from a population that predict a stronger potential for TdP.

Methods

Prolongation data of 30 non‐antiarrhythmic QT prolonging drugs were analysed. Depending on how strong the drugs were associated with TdP, they were categorized as strong or borderline torsadogens. The differences in mean QTc increases between the two groups were compared and cut‐off values that distinguished strong from borderline drugs were searched for.

Results

The average QTc increase of 19.3 millisecond of strong torsadogens was significantly greater than the 8.0 millisecond of borderline torsadogens. Prolongation greater than 12 millisecond in the context of monotherapy or 25 millisecond in the presence of metabolic inhibition and an upper bound of 95% confidence interval (CI) for the mean QTc increase greater than 14 millisecond in monotherapy or 30.1 millisecond in combination therapy with metabolic inhibitors favoured a stronger association with TdP.

Conclusions

Drugs strongly associated with TdP have greater QTc increases than those with less concern. Several cut‐off values have been noted to distinguish between them. These values may be helpful for evaluation of TdP risk for future QT prolonging drugs. Copyright © 2009 John Wiley & Sons, Ltd.
Si based quantum cascade structure: from energy band structures design to materials growth
Authors: Yu Jinzhong , Han Genquan
Published: January 2009

In this paper, we propose an n‐type vertical transition bound‐to‐continuum Ge/SiGe quantum cascade structure utilizing electronic quantum wells in the L and Γ valleys of the Ge layers. The optical transition levels are located in the quantum wells in the L valley. The Γ‐L intervalley scattering is used to depopulate the lower level and inject the electrons into the upper level. We also show that high quality Si1–yGey pseudosubstrate is obtained by thermal annealing of Si1–xGex/Ge/Si structure. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The future of PV industry and SG‐Si materials
Authors: Zhao Yuwen
Published: January 2009

The future demand of solar grade silicon (SG‐Si) materials is discussed from PV Industry future trend in this paper. The production of ultra‐purity silicon (UP‐Si) materials (including EG‐Si and SG‐Si) will be a big industry and will have a great contribution to world society with high‐speed development of PV industry. For demand of future, the purity issue of SG‐Si is discussed from requirement of solar cell performance and operation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Charge storage and light emission properties of three dimension controllable Si nanostructures
Authors: Chen Kunji , Huang Jian , Ma Zhongyuan , Wang Xiang , Yao Yao , Wang Jiumin , Li Wei , Xu Jun , Huang Xinfan
Published: January 2009

Size controllable nanocrystalline silicon (nc‐Si) materials show novel electrical and optical characteristics of silicon quantum dots. Based on laser induced constrained crystallization principle, the one‐/two‐/three‐dimension (1D, 2D and 3D) ordered controllable nc‐Si array have been successfully obtained by using phase‐shifting grating mask combine with multilayer structures. The tunable photoluminescence (PL) and electro‐luminescence (EL) from this kind of nc‐Si films have been observed. The collective single‐electron resonant tunneling and charge storage in the uniform nc‐Si single layer have been studied by using I‐V and the C‐V measurement at room temperature. The double level charge storage in stacked nc‐Si layer based metal‐insulator‐semiconductor (MIS) structure has been demonstrated. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Impurity engineering for germanium‐doped Czochralski silicon wafer used for ultra large scale integrated circuit
Authors: Chen Jiahe , Yang Deren
Published: January 2009

Internal gettering (IG) technology has been challenged by both the reduction of thermal budget during device fabrication and the enlargement of wafer diameter. Improving the properties of Czochralski (Cz) silicon wafers by intentional impurity doping, the so‐called ‘impurity engineering (IE)’, is defined. Germanium has been found to be one of the important impurities for improving the internal gettering effect in Cz silicon wafer. In this paper, the investigations on IE involved with the conventional furnace anneal based denudation processing for germanium‐doped Cz silicon wafer are reviewed. Meanwhile, the potential mechanisms of germanium effects for the IE of Cz silicon wafer are also interpreted based on the experimental facts. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Light emission from ion‐implanted silicon
Authors: Sun J. M. , Helm M. , Skorupa W. , Schmidt B. , Mücklich A.
Published: January 2009

Si pn junction light emitting devices (LEDs) with dislocations were prepared by means of high‐dose B+ and Si+ self‐ion implantation. The Si LEDs with dislocations created by high‐dose boron implantation emit much stronger band edge electroluminescence (EL) compared to the ones with dislocations created by Si+ implantation. At 12 K, the EL peaks from the bound excitons around the dislocations created by high‐dose boron implantation show strong blue shift with increasing the injection current, this suggests that the dislocations are decorated with locally heavy p‐type doping, which originated from boron gettering at the dislocations. The thermal dissociation of the bound excitons leads to an anomalous increase of the band edge electroluminescence with increasing temperature. Finally, efficient silicon LEDs with interdigital micro p‐type doping arrays were demonstrated with a wall‐plug external quantum efficiency of 0.15% by implementing the band gap engineering concept from the modulation doping technology. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The migration of gold on large diameter silicon nanowires in oxygenous system
Authors: Wan Yuting , Wang Yewu , Chen Bo , Fang Yanjun , Sha Jian
Published: January 2009

Silicon nanowires (SiNWs) of about 200‐500 nm in diameter with branch morphology were fabricated by one step in oxygenous chemical vapour deposition (CVD) system. The catalyst Au particles on branches came from the migration of Au on the tip of trunk. We speculate that the migration of gold is due to the large diameter of gold particles. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High‐resolution analytical electron microscopy of silicon nanostructures
Authors: Schade Martin , Geyer Nadine , Fuhrmann Bodo , Heyroth Frank , Werner Peter , Leipner Hartmut S.
Published: January 2009

We report on both the fabrication of hexagonally ordered, vertically aligned silicon nanowires (SiNW) and their characterization by means of analytical transmission electron microscopy. Combining colloidal lithography, plasma etching, and catalytic wet etching, SiNW with well defined diameter, length, and density can be obtained. For this purpose hexagonally closed packed monolayers of monodisperse polystyrene particles are transferred into non‐closed packed particle arrays. These arrays are used as a mask for silver deposition by thermal evaporation. After the lift‐off of the spheres, the silver layer serves as a catalyst for the wet‐etching process in an H2O2/HF solution. In this way, arrays of SiNW of sub‐50 nm diameter with an aspect ratio of up to 10 could be fabricated. Scanning electron microscopy as well as scanning transmission electron microscopy have been applied in order to investigate the morphology, the internal structure and the composition of the catalytically etched SiNW. The analysis yielded a single crystalline, porous structure composed of crystalline silicon and SiOx with x ≤ 2. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synchrotron microscopy and spectroscopy for analysis of crystal defects in silicon
Authors: Seifert Winfried , Vyvenko Oleg F. , Arguirov Tzanimir , Erko Alexei , Kittler Martin , Rudolf Carsten , Salome Murielle , Trushin Maxim , Zizak Ivo
Published: January 2009

The paper discusses the synchrotron‐based microprobe techniques XBIC (X‐ray beam induced current), μ‐XRF (X‐ray fluorescence microscopy) and μ‐XAS (X‐ray absorption microspectroscopy) and their application for studying electrical activity of defects and precipitation of transition metals in Si materials. Investigations were performed on samples of block‐cast multicrystalline Si and on model samples cut from a bonded monocrystalline wafer. To analyze the precipitation sites, Ni, Cu and Fe were introduced intentionally into the samples. The detected precipitates were found to consist of silicides. Evidence for metal precipitates was also found in virtually uncontaminated as‐grown block‐cast Si. Besides Ni precipitates detected at a recombination active grain boundary, particles containing one or several metals (Cu, Fe, Ti, V) were observed. Unexpectedly, these particles seem to exhibit low only recombination activity. Further studies are necessary to identify their nature. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optoelectronic application of Si/Ge heterostructures
Authors: Kasper E. , Oehme M.
Published: January 2009

Silicon germanium heterostructures extend considerably the optoelectronic performance of silicon based systems. Together with small width waveguides on SOI substrates a variety of attractive applications can be tackled as monolithic integrated systems. Examples are on‐chip clock distribution, fiber to the home front ends and infrared arrays for night vision. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)