bluuebunny/crossref_metadata_2025 huggingface dataset:
Tailoring the S‐Selectivity of 2‐Succinyl‐5‐enolpyruvyl‐6‐hydroxy‐3‐cyclohexene‐1‐carboxylate Synthase (MenD) from Escherichia coli
Authors: Westphal Robert , Hahn Doris , Mackfeld Ursula , Waltzer Simon , Beigi Maryam , Widmann Michael , Vogel Constantin , Pleiss Jürgen , Müller Michael , Rother Dörte , Pohl Martina
Published: September 2013

The thiamine diphosphate (ThDP)‐dependent enzyme 2‐succinyl‐5‐enolpyruvyl‐6‐hydroxy‐3‐cyclohexene‐1‐carboxylate synthase from Escherichia coli (EcMenD, E.C. 2.2.1.9) catalyzes the carboligation of α‐ketoglutarate (α‐KG) and various benzaldehyde derivatives with excellent chemo‐ as well as high R‐selectivity (enantiomeric excess (ee) >93 %) to yield chiral α‐hydroxy ketones. Based on the recently developed S‐pocket concept, we engineered S‐selective EcMenD variants by optimizing the steric properties and stabilization of the acceptor substrate in the S‐pocket. Moreover, the moderate S‐selectivity of the EcMenD variant I474A/F475G described recently for the carboligation of α‐KG and benzaldehyde (ee=75 %) could be improved by selective destabilization of the R‐pathway, which resulted in the variant I474A/F475G/R395Y (ee=85 % S). Subsequent investigation of the acceptor substrate range of this new variant revealed high S‐selectivity especially with meta‐substituted benzaldehydes, which gave access to 5‐hydroxy‐4‐oxo‐5‐arylpentanoates with excellent enantioselectivities of up to 99 % ee S. Thus, opening the S‐pocket and simultaneous destabilization of the R‐pathway provides a potential general new strategy to enhance the S‐selectivity of ThDP‐dependent enzymes.
Radial Profiles of Gas Bubble Behavior in a Gas‐Liquid Bubble Column Reactor under Elevated Pressures
Authors: Jin H. , Qin Y. , Yang S. , He G. , Guo Z.
Published: September 2013

The effects of operating conditions on radial variation of gas holdups, bubble swarm rising velocity, and Sauter mean diameter were investigated in a bubble column reactor under elevated pressures using a conductivity probe method. Air served as gas phase and tap water as liquid phase with varying gas velocity and pressure. All three parameters increased constantly with higher superficial gas velocity. Maximum holdup, velocity, and Sauter mean diameter were found at the center of the cross section. Two different cases for Sauter mean diameter distribution were observed. The gas holdups increase continuously with higher system pressure, but decrease for bubble swarm rising velocity and Sauter mean diameter. According to experimental results, an empirical correlation of the gas holdup profiles is presented.
Determination of Measurement Uncertainties in Adiabatic Hot‐Storage Experiments for Reactive Dusts
Authors: Schmidt M. , Wanke C. , Krause U.
Published: September 2013

The formal kinetics of self‐ignition of solid bulk materials theoretically can be derived from just one single adiabatic hot‐storage test. The question arises how uncertainties in the measurements can be quantified and how these uncertainties affect the results of the subsequent predictions. Adiabatic and isoperibolic hot‐storage basket tests were performed for samples of lignite coal, black coal, cork dust, a polymer dust, and wax‐coated silicid acid. In the adiabatic experiments, the starting temperature and the temperature control of the oven were varied systematically to study the uncertainty margin of adiabatic tests. The apparent activation energy and the pre‐exponential factor of the lumped reaction were derived from the adiabatic tests including average values and standard deviations and compared to isoperibolic experiments performed according to the European standard EN 15188. It could be shown that with a precise temperature control of the adiabatic oven combined with an automated computation of the maximum rate of temperature rise the uncertainty of the apparent activation energy can be limited to less than 10 %.
Baker's Yeast Behavior during Vacuum Agitated Contact Drying
Authors: Bennamoun L. , Afzal M. , Léonard A.
Published: September 2013

Drying is considered as an intensive operation that consumes large quantities of energy. Usually, baker's yeast is obtained using freeze drying or fluidized‐bed drying, both of which are considered as expensive technologies. So, exploring other techniques such as contact drying could limit this disadvantage. In addition, no work dealing with contact drying of baker's yeast has been accomplished yet. Therefore, here, the behavior of baker's yeast during vacuum agitated contact drying is presented. The results show that the drying process can be divided into three phases: the pasty phase, the lumpy phase, and the granular phase. The influence of the drying parameters, such as the temperature, the impeller velocity, and the initial mass, was also studied. It was found that the wall temperature and the impeller velocity have a positive effect on the drying kinetics, as their increase allows a reduction in the drying time. Nevertheless, an increase in the pressure level or the initial mass of the product caused the drying time to increase.
Ion‐Pairing of Phosphonium Salts in Solution: CH⋅⋅⋅Halogen and CH⋅⋅⋅π Hydrogen Bonds
Authors: Ammer Johannes , Nolte Christoph , Karaghiosoff Konstantin , Thallmair Sebastian , Mayer Peter , de Vivie‐Riedle Regina , Mayr Herbert
Published: September 2013

The 1H NMR chemical shifts of the C(α)H protons of arylmethyl triphenylphosphonium ions in CD2Cl2 solution strongly depend on the counteranions X−. The values for the benzhydryl derivatives Ph2CHPPh3+ X−, for example, range from δH=8.25 (X−=Cl−) over 6.23 (X−=BF4−) to 5.72 ppm (X−=BPh4−). Similar, albeit weaker, counterion‐induced shifts are observed for the ortho‐protons of all aryl groups. Concentration‐dependent NMR studies show that the large shifts result from the deshielding of the protons by the anions, which decreases in the order Cl− > Br− ≫ BF4− > SbF6−. For the less bulky derivatives PhCH2PPh3+ X−, we also find CH⋅⋅⋅Ph interactions between C(α)H and a phenyl group of the BPh4− anion, which result in upfield NMR chemical shifts of the C(α)H protons. These interactions could also be observed in crystals of (p‐CF3‐C6H4)CH2PPh3+ BPh4−. However, the dominant effects causing the counterion‐induced shifts in the NMR spectra are the CH⋅⋅⋅X− hydrogen bonds between the phosphonium ion and anions, in particular Cl− or Br−. This observation contradicts earlier interpretations which assigned these shifts predominantly to the ring current of the BPh4− anions. The concentration dependence of the 1H NMR chemical shifts allowed us to determine the dissociation constants of the phosphonium salts in CD2Cl2 solution. The cation–anion interactions increase with the acidity of the C(α)H protons and the basicity of the anion. The existence of CH⋅⋅⋅X− hydrogen bonds between the cations and anions is confirmed by quantum chemical calculations of the ion pair structures, as well as by X‐ray analyses of the crystals. The IR spectra of the Cl− and Br− salts in CD2Cl2 solution show strong red‐shifts of the CH stretch bands. The CH stretch bands of the tetrafluoroborate salt PhCH2PPh3+ BF4− in CD2Cl2, however, show a blue‐shift compared to the corresponding BPh4− salt.
Titanium Carbide and Carbide‐Derived Carbon Composite Nanofibers by Electrospinning of Ti‐Resin Precursor
Authors: Martin Jan R. , Borchardt Lars , Oschatz Martin , Mondin Giovanni , Kaskel Stefan
Published: September 2013

TiO2/C and TiC/C composite nanofibers were produced by electrospinning of resin/TiCl4 precursor solution. The resulting ceramic fiber webs were porous and showed surface areas as high as 523 m2g–1. They were further converted to carbide‐derived carbon (CDC) fibers under full retention of the fiber‐like shape and flexibility. These CDC membranes showed a hierarchical pore structure and specific surface as high as 1378 m2g–1. Applications in the area of high temperature filtration, catalyst support and energy storage are conceivable.
Lightweight distributed geographical: a lightweight distributed protocol for virtual clustering in geographical forwarding cognitive radio sensor networks
Authors: Zubair Suleiman , Fisal Norsheila , Abazeed Mohammed B. , Salihu Bala Alhaji , Khan Adnan Shahid
Published: September 2013

Recent literature characterizes future wireless sensor networks (WSN) with dynamic spectrum capabilities. When cognitive radio is introduced as a main component of a network, a network management protocol is needed to ensure network connectivity and stability especially in highly dynamic environments. Implementing such protocols in WSN opens more challenges because of the resource constraints in sensor networks. We propose a distributed lightweight solution that fulfills this need for WSN. With this protocol, a node in a multichannel environment is quickly able to establish a control channel with neighboring nodes. Lightweight distributed geographical either increases or reduces the coverage area of the control channel based on perceived interference and adequately takes care of intersecting nodes with minimal overhead. By identifying local minima nodes, it also has the potentiality of reducing route failure by 70% further reducing the time and energy overhead incurred by switching to angle routing or maximum power transmission schemes usually used to solve the local minima issue. The work shows best operating values in terms of duty cycle and signal to noise ratio threshold frequencies and the lightweight nature of lightweight distributed geographical in terms of energy and communication overhead, which suits network management protocols for cognitive radio sensor networks. Copyright © 2013 John Wiley & Sons, Ltd.
The behavioral and endocrinological development of stress response in dogs
Authors: Nagasawa Miho , Shibata Yoh , Yonezawa Akiko , Morita Tomoko , Kanai Masanori , Mogi Kazutaka , Kikusui Takefumi
Published: September 2013

Endocrinological stress response has been shown to be absent in a specific period of the early life of rodents; this is named the stress‐hyporesponsive period (SHRP). The SHRP is a significant period for the appropriate development of infants. In this study, the presence of SHRP in dogs was identified by conducting a 5‐min separation test in 142 Labrador retriever puppies in their early socialization period and measuring the changes in urinary cortisol levels. An increase in cortisol after separation was found after 5 weeks of age, suggesting that the SHRP persists until 4 weeks of age in dogs. The distress vocalization during separation changed and the lactating behavior decreased rapidly around 5 weeks of age, suggesting that the endocrinological and emotional aspects of development change at approximately 5 weeks of age and maternal inhibition of cortisol might occur in dogs as well as rodents. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 726–733, 2014.
Early deprivation impairs the development of balance and bilateral coordination
Authors: Roeber Barbara J. , Gunnar Megan R. , Pollak Seth D.
Published: September 2013

This study examined balance and bilateral coordination skills in a sample of internationally adopted, post‐institutionalized (PI) children. We compared the performance of these PI children to two age‐matched groups. One was a group of children who were internationally adopted from foster care (FC). The second group consisted of non‐adopted children being raised in their birth families, who served as controls (Control). Both PI and FC children scored lower than control children on balance, while PI children scored lower than both FC and control children on bilateral coordination. These results suggest that aspects of institutional rearing impact the development of bilateral coordination, while factors common to internationally adopted children other than institutionalization impact the development of balance. Region of birth (Asia, Latin/South America, Russia/Eastern Europe) did not moderate associations between institutional duration and bilateral coordination. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 1110–1118, 2014.
Subtypes of type I IFN differentially enhance cytokine expression by suboptimally stimulated CD4+T cells
Authors: Hillyer Philippa , Raviv Nataly , Gold Doria M. , Dougherty Danielle , Liu Jie , Johnson Teresa R. , Graham Barney S. , Rabin Ronald L.
Published: September 2013

Human type I interferons (IFNs) include IFN‐β and 12 subtypes of IFN‐α. During viral infection, infiltrating memory CD4+ T cells are exposed to IFNs, but their impact on memory T‐cell function is poorly understood. To address this, we pretreated PBMCs with different IFNs for 16 h before stimulation with Staphylococcus aureus enterotoxin B and measured cytokine expression by flow cytometry. IFN‐α8 and ‐α10 most potently enhanced expression of IFN‐γ, IL‐2, and IL‐4. Potency among the subtypes differed most at doses between 10 and 100 U/mL. While enhancement of IL‐2 and IL‐4 correlated with the time of preincubation with type I IFN, IFN‐γ production was enhanced best when IFN‐α was added immediately preceding or simultaneously with T‐cell stimulation. Comparison of T‐cell responses to multiple doses of Staphylococcus aureus enterotoxin B and to peptide libraries from RSV or CMV demonstrated that IFN‐α best enhanced cytokine expression when CD4+ T cells were suboptimally stimulated. We conclude that type I IFNs enhance Th1 and Th2 function with dose dependency and subtype specificity, and best when T‐cell stimulation is suboptimal. While type I IFNs may beneficially enhance CD4+ T‐cell memory responses to vaccines or viral pathogens, they may also enhance the function of resident Th2 cells and exacerbate allergic inflammation.
A 2D Layered Lanthanide Hydroxide Showing Slow Relaxation of Magnetization – Dy8(OH)20Cl4·6H2O
Authors: Monteiro Bernardo , Pereira Cláudia C. L. , Coutinho Joana T. , Pereira Laura C. J. , Marçalo Joaquim , Almeida Manuel
Published: September 2013

The magnetic properties of the layered lanthanide hydroxide Dy8(OH)20Cl4·6H2O were studied. Below 5 K, slow magnetic relaxation was observed even in the absence of an external field, with a blocking temperature of 3 K and an energy barrier of 36.1 K, a behavior characteristic of single‐molecule magnets.
Using fluidized bed and flume experiments to quantify cohesion development from aging and drainage
Authors: Nouwakpo Sayjro Kossi , Huang Chi‐hua , Weltz Mark A. , Pimenta Flavia , Chagas Isis , Lima Luiz
Published: September 2013

Temporal variations in soil erosion resistance are often the result of decreased soil cohesion due to physical disruption followed by a regain of soil strength through a process called aging, stabilization or consolidation. The goal of this study was to quantify changes in soil cohesion due to aging and subsurface hydrologic condition using a fluidized bed method. A flume experiment was also used to verify that findings from the fluidized bed experiment translated into measurable changes in soil erodibility. Tests were performed on three different soils (a Miami soil, a Cecil soil and Crosby–Miami soil complex). Changes in soil cohesion due to aging and drainage state were successfully detected by the fluidized bed technique. For all soils tested, cohesion developed in a two‐stage process where an increase in cohesion with aging duration immediately after the soil was rewetted, was followed by a decrease in cohesion which often started after 24 h of aging. When soils were aged at field capacity, the resulting cohesion measured by the fluidized bed method was on average 3.13 times higher than that measured when aging was performed at saturation. Trends in soil rill erodibility Kr with aging duration measured in the flume experiment were consistent with the two‐stage pattern observed in soil cohesion estimates but the legacy effect of suction applied at field capacity faded after 72 h of aging. Copyright © 2013 John Wiley & Sons, Ltd.
Detection of acoustic‐gravity waves in lower ionosphere by VLF radio waves
Authors: Nina A. , Čadež V. M.
Published: September 2013

We present a new method to study harmonic waves in the low ionosphere (60–90 km) by detecting their effects on reflection of very low frequency (VLF) radio waves. Our procedure is based on amplitude analysis of reflected VLF radio waves recorded in real time, which yields an insight into the dynamics of the ionosphere at heights where VLF radio waves are being reflected. The method was applied to perturbations induced by the solar terminator motions at sunrises and sunsets. The obtained results show that typical perturbation frequencies found to exist in higher regions of the atmosphere are also present in the lower ionosphere, which indicates a global nature of the considered oscillations. In our model atmosphere, they turn out to be the acoustic and gravity waves with comparatively short and long periods, respectively.
Mid‐depth mixing linked to North Atlantic Current variability
Authors: Walter Maren , Mertens Christian
Published: September 2013

Repeated observations at the subpolar front west of the Mid‐Atlantic Ridge show a link between the position of the North Atlantic Current (NAC) and the spatial distribution of fine‐scale variance, diapycnal diffusivity, and integrated energy dissipation. Observational data were collected during three cruises. A single branch of the NAC was found in 2008, approximately at 50°30′N, and two branches were observed in 2010 and 2011, with alternating intensities. Shear variance was elevated below the core of the NAC in all cases, resulting in an average diapycnal diffusivity that is higher by a factor of 3 compared to the averages north and south of the NAC. The integrated energy dissipation has maxima at or south of the fronts; background dissipation is highest during 2008, also the year with the highest surface eddy kinetic energy.
Longitudinal missing data strategies for substance use clinical trials using generalized estimating equations: an example with a buprenorphine trial
Authors: McPherson Sterling , Barbosa‐Leiker Celestina , McDonell Michael , Howell Donelle , Roll John
Published: September 2013

Objective

A review of substance use clinical trials indicates that sub‐optimal methods are the most commonly used procedures to deal with longitudinal missing information.

Methods

Listwise deletion (i.e., using complete cases only), positive urine analysis (UA) imputation, and multiple imputation (MI) were used to evaluate the effect of baseline substance use and buprenorphine/naloxone tapering schedule (7 or 28 days) on the probability of a positive UA (UA+) across the 4‐week treatment period.

Results

The listwise deletion generalized estimating equations (GEE) model demonstrated that those in the 28‐day taper group were less likely to submit a UA+ for opioids during the treatment period (odds ratios (OR) = 0.57, 95% confidence interval (CI): 0.39–0.83), as did the positive UA imputation model (OR = 0.43, CI: 0.34–0.55). The MI model also demonstrated a similar effect of taper group (OR = 0.57, CI: 0.42–0.77), but the effect size was more similar to that of the listwise deletion model.

Conclusions

Future researchers may find utilization of the MI procedure in conjunction with the common method of GEE analysis as a helpful analytic approach when the missing at random assumption is justifiable. Copyright © 2013 John Wiley & Sons, Ltd.
Trend and extreme occurrence of precipitation in a mid‐latitude Eurasian steppe watershed at various time scales
Authors: Wang Xixi , Yang Xiaomin , Liu Tingxi , Li Fengling , Gao Ruizhong , Duan Limin , Luo Yanyun
Published: September 2013

The confounding effects of step change invalidate the stationarity assumption of commonly used trend analysis methods such as the Mann–Kendall test technique, so previous studies have failed to explain inconsistencies between detected trends and observed large precipitation anomalies. The objectives of this study were to (1) formulate a trend analysis approach that considers nonstationarity due to step changes, (2) use this approach to detect trends and extreme occurrences of precipitation in a mid‐latitude Eurasian steppe watershed in North China, and (3) examine how runoff responds to precipitation trends in the study watershed. Our results indicate that annual precipitation underwent a marginal step jump around 1995. The significant annual downward trend after 1994 was primarily due to a decrease in summer rainfall; other seasons exhibited no significant precipitation trends. At a monthly scale, July rainfall after 1994 exhibited a significant downward trend, whereas precipitation in other months had no trend. The percentage of wet days also underwent a step jump around 1994 following a significant decreasing trend, although the precipitation intensity exhibited neither a step change nor any significant trend. However, both low‐frequency and high‐frequency precipitation events in the study watershed occurred more often after than before 1994; probably as either a result or an indicator of climate change. In response to these precipitation changes, the study watershed had distinctly different precipitation‐runoff relationships for observed annual precipitations of less than 300 mm, between 300 and 400 mm, and greater than 400 mm. Copyright © 2013 John Wiley & Sons, Ltd.
Dynamic molecular monitoring of retina inflammation byin vivoRaman spectroscopy coupled with multivariate analysis
Authors: Marro Monica , Taubes Alice , Abernathy Alice , Balint Stephan , Moreno Beatriz , Sanchez‐Dalmau Bernardo , Martínez‐Lapiscina Elena H. , Amat‐Roldan Ivan , Petrov Dmitri , Villoslada Pablo
Published: September 2013

Retinal tissue is damaged during inflammation in Multiple Sclerosis. We assessed molecular changes in inflamed murine retinal cultures by Raman spectroscopy. Partial Least Squares‐Discriminant analysis (PLS‐DA) was able to classify retina cultures as inflamed with high accuracy. Using Multivariate Curve Resolution (MCR) analysis, we deconvolved 6 molecular components suffering dynamic changes along inflammatory process. Those include the increase of immune mediators (Lipoxygenase, iNOS and TNFα), changes in molecules involved in energy production (Cytochrome C, phenylalanine and NADH/NAD+) and decrease of Phosphatidylcholine. Raman spectroscopy combined with multivariate analysis allows monitoring the evolution of retina inflammation.

Raman spectroscopy analysis of the Retinal Ganglion Cell layer of the retina. (A) Design of the analysis of the Ganglion cell layer (GCL) and Retinal Nerve Fiber Layer (RNFL) of the retina based in the physical properties of laser light and anatomical structure of retinal layers. (B) Examples of raw Raman spectra from representative retina sample after 10 hours incubation time (black) and LPS treated retina sample after 10 hours incubation time (red) and 12 hours incubation time (blue). (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Radius dependence of solute concentration estimates of simulated ultrafine precipitates
Authors: Serizawa Ai , Miller Michael K.
Published: September 2013

Estimates of the radii and solute concentrations of simulated microstructures containing ultrafine spherical precipitates were determined from isoconcentration surfaces and proximity histograms. The accuracy of the estimates of the solute concentrations and the radii of precipitates was found to depend on the size of precipitates. Optimized parameters for analyzing 0.5‐ to 2‐nm‐radius precipitates are proposed. The solute content of 0.5‐nm‐radius precipitates was not estimated correctly by this method. The accuracy of the estimates of the solute concentration and the radius of precipitates were primarily influenced by the solute concentrations of the precipitates. The ranges of error of the solute concentration in the precipitates, which are associated with the analytical limitations of the ultrafine precipitates, were determined, and the results indicated a limitation of the estimates. Microsc. Res. Tech. 76:1196–1203, 2013. © 2013 Wiley Periodicals, Inc.
Isolation and characterization of two satellite DNAs in some Iberian rock lizards (Squamata, Lacertidae)
Authors: Giovannotti Massimo , Rojo Verónica , Nisi Cerioni Paola , González‐Tizón Ana , Martínez‐Lage Andrés , Splendiani Andrea , Naveira Horacio , Ruggeri Paolo , Arribas óscar , Olmo Ettore , Caputo Barucchi Vincenzo
Published: September 2013

Satellite DNAs represent a large portion of all high eukaryotic genomes. They consist of numerous very similar repeated sequences, tandemly arranged in large clusters up to 100 million base pairs in length, usually located in the heterochromatic parts of chromosomes. The biological significance of satDNAs is still under discussion, but most of their proposed functions are related to heterochromatin and/or centromere formation and function. Because information about the structure of reptilian satDNA is far from exhaustive, we present a molecular and cytogenetic characterization of two satDNA families in four lacertid species. Two families of tandemly repeated DNAs, namely TaqI and HindIII satDNAs, have been cloned and sequenced from four species belonging to the genus Iberolacerta. These satDNAs are characterized by a monomer length of 171–188 and 170–172 bp, and by an AT content of 60.5% and 58.1%, respectively. FISH experiments with TaqI satDNA probe produced bright signals in pericentromeric regions of a subset of chromosomes whereas all the centromeres were marked by HindIII probe. The results obtained in this study suggest that chromosome location and abundance of satDNAs influence the evolution of these elements, with centromeric families evolving tenfold faster than interstitial/pericentromeric ones. Such different rates render different satellites useful for phylogenetic investigation at different taxonomic ranks. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 13–26, 2014. © 2013 Wiley Periodicals, Inc.
Crystal orientation results in different amorphization of olivine during solar wind implantation
Authors: Li Yang , Li Xiongyao , Wang Shijie , Li Shijie , Tang Hong , Coulson Ian M.
Published: September 2013

Crystal orientation plays an important role in mineral amorphization during solar wind implantation. To discuss these effects, ion implantation experiments were carried out to irradiate natural olivine grains by 1 × 1017 cm−2 50 keV He+. Based on the olivine grains irradiated in our experiment, residual crystal planes have been identified by reference to the crystal plane's spacing shown in diffraction images. It is found that He+ ions injected along [010] damages the olivine structure more effectively than with other orientations and that this possibly relates to the higher atomic density and the vertical impact of the flux on MO6 (where M commonly represents Fe2+ and Mg2+) octahedra chains. Crystal planes perpendicular or approximately perpendicular to [010] may be destroyed easily during the early stages of irradiation, particularly for (040). However, crystal planes, such as (041), (021), (022), (120), and (140), parallel to [100] or [001] may survive until the final stages of olivine amorphization. These different characteristics affected by crystal orientation in ion implantation might help researchers to better understand the process of solar wind weathering and in dating the exposure time of lunar and asteroidal soil grains as well as interplanetary dust particles affected by the solar wind.
In the hot seat: Insolation, ENSO, and vegetation in the African tropics
Authors: Ivory Sarah J. , Russell Joellen , Cohen Andrew S.
Published: September 2013

African climate is changing at rates unprecedented in the Late Holocene with profound implications for tropical ecosystems and the global hydrologic cycle. Understanding the specific climate drivers behind tropical ecosystem change is critical for both future and paleomodeling efforts. However, linkages between climate and vegetation in the tropics have been extremely controversial. The Normalized Difference Vegetation Index (NDVI) is a satellite‐derived index of vegetation productivity with a high spatial and temporal resolution. Here we use regression analysis to show that NDVI variability in Africa is primarily correlated with the interannual extent of the Intertropical Convergence Zone (ITCZ). Our results indicate that interannual variability of the ITCZ, rather than sea surface temperatures or teleconnections to middle/high latitudes, drives patterns in African vegetation resulting from the effects of insolation anomalies and El Niño–Southern Oscillation (ENSO) events on atmospheric circulation. Global controls on tropical atmospheric circulation allow for spatially coherent reconstruction of interannual vegetation variability throughout Africa on many time scales through regulation of dry season length and moisture convergence, rather than precipitation amount.
Impact of Epstein–Barr virus load, virus genotype, and frequency of the 30 bp deletion in the viral BNLF‐1 gene in patients harboring the human immunodeficiency virus
Authors: Giron Leila Bertoni , Ramos da Silva Suzane , Barbosa Alexandre Naime , Monteiro de Barros Almeida Ricardo Augusto , Rosário de Souza Lenice do , Elgui de Oliveira Deilson
Published: September 2013

Patients infected with the human immunodeficiency virus (HIV) are at higher risk of developing Epstein–Barr Virus (EBV)‐associated lymphomas. The usefulness of monitoring EBV in peripheral blood mononuclear cells (PBMCs) of patients infected with HIV has not been established. The aim of this study was to evaluate the EBV viral load in PBMCs, the frequency of viral genotypes, and the presence of the 30‐bp deletion in the BNLF‐1 gene. DNA samples from 156 patients attending the HIV/AIDS Day Clinic at Botucatu School of Medicine, Sao Paulo State University were evaluated. The EBV viral load was detectable by real time PCR in 123/156 (78.8%) cases and was higher in patients not receiving antiretroviral treatment or under therapeutic failure than in patients under successful highly active antiretroviral therapy (HAART) (P = 0.0076). Overall, the profile of patients with high EBV viral load included elevated HIV viremia (P = 0.0005), longer time of HIV diagnosis (P = 0.0026), and increased levels of T CD8+ lymphocytes (P = 0.0159). The successful amplification of the EBNA‐2 gene by nested‐PCR was achieved in 95 of 123 (77.2%) cases, of which 75.8% were EBV‐1, 9.5% EBV‐2, and 14.7% were co‐infected with both EBV‐1 and ‐2. The analysis of the BNLF‐1 gene was possible in 99 of 123 (80.5%) cases, of which 50.5% had the 30‐bp deletion. EBV‐1 was more common than EBV‐2, which may reflect the fact that the cohort was predominantly Caucasian and heterosexual. J. Med. Virol. 85:2110–2118, 2013. © 2013 Wiley Periodicals, Inc.
Comparison of the effect of intra‐tendon applications of recombinant human platelet‐derived growth factor‐BB, platelet‐rich plasma, steroids in a rat achilles tendon collagenase model
Authors: Solchaga Luis A. , Bendele Alison , Shah Vivek , Snel Leo B. , Kestler Hans K. , Dines Joshua S. , Hee Christopher K.
Published: September 2013

This study compared the effect of intra‐tendon (IT) delivery of recombinant human platelet‐derived growth factor‐BB (rhPDGF‐BB), platelet‐rich plasma (PRP) and corticosteroids in a rat tendinopathy model. Seven days after collagenase induction of tendinopathy, a 30‐µl IT injection was administered. Treatments included: saline; 3 µg rhPDGF‐BB; 10 µg rhPDGF‐BB; PRP; and 300 µg triamcinolone acetonide (TCA). Outcomes were assessed 7 and 21 days after treatment. All groups exhibited good to excellent repair. Relative to saline, cell proliferation increased 65% in the 10 µg rhPDGF‐BB group and decreased 74% in the TCA group; inflammation decreased 65% in the TCA group. At 7 days, maximum load‐to‐failure was increased in the 3 µg rhPDGF‐BB group relative to saline, PRP, and TCA (p < 0.025). On day 21, maximum load‐to‐rupture was increased in the 10 µg rhPDGF‐BB group relative to saline, PRP, and TCA (p < 0.035) and in the 3 µg rhPDGF‐BB group compared to saline and TCA (p < 0.027). Stiffness in the 10 µg rhPDGF‐BB group was increased compared to saline, PRP, and TCA (p < 0.038). Histology demonstrated similar repair in all groups. PRP and TCA did not improve mechanical properties compared to saline. Injections of rhPDGF‐BB increased maximum load‐to‐failure (3 and 10 µg) and stiffness (10 µg) relative to controls and commonly used treatments. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:145–150, 2014.
Leadership Sustainability
Authors: Ulrich Dave , Smallwood Norm
Published: September 2013

Today's leaders require leadership sustainability, the ability to make personal improvements stick over the long term. Ulrich and Smallwood contend that leaders fail at the stage of implementation, even after enthusiastically embracing coaching, learning, and other performance improvement efforts. The challenge, they write, “is how to turn these events into an ongoing pattern.” Their research found seven principles driving sustainability: simplicity, time, accountability, resources, tracking, melioration (“a new term for a whole complex of actions and attitudes designed to make things better”), and emotion. They also list more than 20 crucial books on such subjects as change, influence, and self‐discipline.
Dream On
Authors: Malham Howell J.
Published: September 2013

Malham makes a bold assertion about concepts such as vision, imagination, and innovation: “If a vision is a vision about something that's possible, given the existing technology and know‐how, then it's not really a vision at all.” He challenges leaders to employ strategic imagination, including these five rules: (1) stop with the data; (2) game out failure; (3) dream your narrative; (4) don't just think the unthinkable, speak it; and (5) muster true belief. “When we imagine strategically,” he writes, “we doubt. Doubting leads to inquiry, and inquiry leads to the truth.”
Judging Others Has Not Worked … So Let's Join Them
Authors: Katz Judith H. , Miller Frederick A.
Published: September 2013

Within organizations, there is a crucial distinction between judging others and joining them. Katz and Miller contend when we are instinctively wary of others it “slows us down in a world that demands speed.” When in joining mode, you gain more and faster collaboration, better acceptance of others, the exploration of ideas, and the cultivation of curiosity. Leaders can listen as allies with others, pay attention to their perspectives, and be self‐aware of the times when they are in judging mode. “Judging others,” the authors write, “creates waste in our interactions at a time when organizations have little tolerance for waste.”
Using single transients on the performance analysis of electrochemical noise amplifiers
Authors: Bierwirth M.
Published: September 2013

The acquisition of electrochemical noise is always connected with the question of appropriate measuring devices. The noise measurement system shall allow to process the apparent fluctuations in an electrochemical cell in the low millivolt or microampere range and to record them without any changes. The measurement amplifier is an essential part of the measurement system, but its behavior in the chain of signal processing is difficult to define by a corrosion expert. The present article shows possibilities for the determination of the performance of a noise measurement amplifier. A dummy cell model is often used to get a realistic approach to the sources of electrochemical noise. This article introduces a model describing the generation of single transients from the basic electrochemical corrosion reactions. The model determines fluctuations in the potential which can be measured as voltage fluctuations on a real dummy cell circuit. With the help of a special arbitrary signal generator, artificial noise transients based on this description are applied to a commercial noise measurement system. The acquired signals are compared with the original signals from the signal source and the influences of the noise amplifier on the signals are discussed.
The effect of passive layer stability on electrochemical noise signals arising from pitting corrosion of stainless steels
Authors: Klapper H. S. , Heyn A. , Burkert A. , Goellner J.
Published: September 2013

Electrochemical noise (EN) enables corrosion research and monitoring in real time and with high sensitivity. In the case of submicroscopic nucleation events of pitting corrosion it has been observed that the cathodic process plays a decisive role in the mechanism as well as in the origin of EN signals, which depend not only on the metallic dissolution reaction but also on the electron‐consuming process. EN signals arising from the nucleation process of localized corrosion on stainless steels can only be recorded due to the inhibition effect on the cathodic process achieved by the spontaneous formation of the passive layer. In consequence, passive layer stability becomes a significant factor in influencing EN signals. The way in which the passive layer stability affects the acquisition and analysis of EN signals arising from pitting corrosion on stainless steels is discussed in detail.
Hydrogen and carbon isotope fractionation during degradation of chloromethane by methylotrophic bacteria
Authors: Nadalig Thierry , Greule Markus , Bringel Françoise , Vuilleumier Stéphane , Keppler Frank
Published: September 2013

Chloromethane (CH3Cl) is a widely studied volatile halocarbon involved in the destruction of ozone in the stratosphere. Nevertheless, its global budget still remains debated. Stable isotope analysis is a powerful tool to constrain fluxes of chloromethane between various environmental compartments which involve a multiplicity of sources and sinks, and both biotic and abiotic processes. In this study, we measured hydrogen and carbon isotope fractionation of the remaining untransformed chloromethane following its degradation by methylotrophic bacterial strains Methylobacterium extorquens CM4 and Hyphomicrobium sp. MC1, which belong to different genera but both use the cmu pathway, the only pathway for bacterial degradation of chloromethane characterized so far. Hydrogen isotope fractionation for degradation of chloromethane was determined for the first time, and yielded enrichment factors (ε) of −29‰ and −27‰ for strains CM4 and MC1, respectively. In agreement with previous studies, enrichment in 13C of untransformed CH3Cl was also observed, and similar isotope enrichment factors (ε) of −41‰ and −38‰ were obtained for degradation of chloromethane by strains CM4 and MC1, respectively. These combined hydrogen and carbon isotopic data for bacterial degradation of chloromethane will contribute to refine models of the global atmospheric budget of chloromethane.
Spinal reconstruction for osteomyelitis with free vascularized fibular grafts using intra‐abdominal recipient vessels: A series of three cases
Authors: Aliano Kristen A. , Agulnick Marc , Cohen Benjamin , Gonya Gary , Low Christopher , Stavrides Steve , Addona Tommaso , Goncalves John , Shin David , Kilgo Matthew S. , Davenport Thomas A.
Published: September 2013

Reconstruction of bony defects in the surgical management of vertebral osteomyelitis is a challenging endeavor. Our objective is to report the use of intra‐abdominal vessels as the recipient vessels for microanastomosis of vascularized bone graft and the use of a spinal cage for fixation. Three patients failed conservative treatment for vertebral osteomyelitis and suffered pathologic fracture. Their treatment consisted of staged posterior irrigation and debridement with segmental fixation, followed by a thoracoabdominal approach multiple‐level corpectomy. Reconstruction was performed with a free vascularized fibular graft placed within a custom, expandable cage. The vascularized fibular graft was anastomosed to an intra‐abdominal recipient vessel. All patients improved clinically with no neurologic deficits noted. All showed evidence of successful fusion. Free vascularized bone grafts continue to be an excellent option for multi‐level spinal defects related to osteomyelitis. Intra‐abdominal recipient vessels are appropriate recipient vessels, as their diameter, length, and accessibility allow vascularized bone graft reconstruction of vertebral column defects of the thoracolumbar region. These vessels are also easily accessible and the anastomoses can be performed in the superficial operating incision. © 2013 Wiley Periodicals, Inc. Microsurgery 33:560–566, 2013.
Cancer cell‐derived lymphotoxin mediates reciprocal tumour–stromal interactions in human ovarian cancer by inducing CXCL11 in fibroblasts
Authors: Lau Tat‐San , Chung Tony Kwok‐Hung , Cheung Tak‐Hong , Chan Loucia Kit‐Ying , Cheung Leonard Wing‐Hong , Yim So‐Fan , Siu Nelson Shing‐Shun , Lo Kwok‐Wai , Yu May Mei‐Yung , Kulbe Hagen , Balkwill Frances R , Kwong Joseph
Published: September 2013

We have investigated the role of cytokine lymphotoxin in tumour–stromal interactions in human ovarian cancer. We found that lymphotoxin overexpression is commonly shared by the cancer cells of various ovarian cancer subtypes, and lymphotoxin‐beta receptor (LTBR) is expressed ubiquitously in both the cancer cells and cancer‐associated fibroblasts (CAFs). In monoculture, we showed that ovarian cancer cells are not the major lymphotoxin‐responsive cells. On the other hand, our co‐culture studies demonstrated that the cancer cell‐derived lymphotoxin induces chemokine expression in stromal fibroblasts through LTBR–NF‐κB signalling. Amongst the chemokines being produced, we found that fibroblast‐secreted CXCL11 promotes proliferation and migration of ovarian cancer cells via the chemokine receptor CXCR3. CXCL11 is highly expressed in CAFs in ovarian cancer biopsies, while CXCR3 is found in malignant cells in primary ovarian tumours. Additionally, the overexpression of CXCR3 is significantly associated with the tumour grade and lymph node metastasis of ovarian cancer, further supporting the role of CXCR3, which interacts with CXCL11, in promoting growth and metastasis of human ovarian cancer. Taken together, these results demonstrated that cancer‐cell‐derived lymphotoxin mediates reciprocal tumour–stromal interactions in human ovarian cancer by inducing CXCL11 in fibroblasts. Our findings suggest that lymphotoxin–LTBR and CXCL11–CXCR3 signalling represent therapeutic targets in ovarian cancer. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Insulin degludec (Tresiba): new ultra long‐acting basal insulin
Authors: Chaplin Steve , Joseph Frank
Published: September 2013

Insulin degludec is a new long‐acting insulin for use in type 1 and 2 diabetes. In our New products review, Steve Chaplin presents the clinical data relating to its efficacy and adverse events, and Dr Frank Joseph discusses its place in diabetes treatment compared with other longacting insulins.
Negative thermal expansion in transversely isotropic space frame trusses
Authors: Lim Teik‐Cheng
Published: September 2013

The negative thermal expansion (NTE) of a type of space frame structure is investigated herein. On the basis of a space frame structure consisting of tetrahedral representative volume elements, a volumetric thermal strain and a volumetric coefficient of thermal expansion (CTE) models are developed in this paper. The NTE trusses developed herein exhibit a special case of anisotropy known as transverse isotropy. This is achieved by using two types of rod materials, each for the three apex rods and the three base rods. From these models, the conditions for attaining negative volumetric strain and negative coefficients of volumetric expansion due to change in temperature are established. Two definitions of NTE are given herein: (a) overall NTE and (b) incremental NTE. Based on these two definitions of NTE, the conditions that lead to (i) definite NTE and (ii) selective NTE are established. Plotted results reveal a trend in which the extent of negative thermal expansion is increased for lower apex‐to‐base rod length and CTE ratios, and higher base rod CTE.
The Effect of Intercritical Annealing on the Microstructure and Mechanical Properties in a High Strength TRIP Steel with C‐Partitioning
Authors: Wang Chao , Ding Hua , Tang Zhengyou , Zhang Jun , Di Huafang
Published: September 2013

Direct experimental evidence confirms the partitioning of C to austenite during intercritical annealing is the intrinsic factor that affects the stability of the retained austenite for a newly developed high strength transformation‐induced plasticity (TRIP) steel. The volume fraction of retained austenite and C concentration decreases with increasing intercritical annealing time. Few retained austenite grains and a number of M/A islands were observed in the sample at 830°C annealed for 30 min. When the sample annealed at 830°C for 0.5 min and then isothermally treated at 440°C for 3 min, the investigated low alloy TRIP steel achieved the tensile strength higher than 1000 MPa, the total elongation of 21.8% and the n‐value of 0.32.
A simplified model for analysis of high‐rise buildings equipped with hysteresis damped outriggers
Authors: Deng Kailai , Pan Peng , Lam Alexandre , Xue Yantao
Published: September 2013

A simplified model is developed to estimate the seismic response of high‐rise buildings equipped with hysteresis damped outriggers. In the simplified model, the core tube is considered as a cantilever beam, and the effects of outriggers on the core tube are considered as concentrated moments. Modal decomposition method is adopted to obtain the seismic response of the simplified model. To investigate the accuracy and effectiveness of the simplified model, a high‐rise building with a height of 160 m was adopted as the example structure, and its response subjected to a ground motion was analyzed using the simplified model. A corresponding finite element model was built and analyzed by a finite element program called SAP2000 (Computers and Structures, Inc. Berkeley, California, United States). The analysis results obtained from the two models were compared. To consider the randomness of the ground motion, comparisons between the two models were further conducted using another 22 ground motions. It is found that the analysis results obtained from the simplified model agree well with those obtained from the finite element model, and the computation time used for the simplified model is almost negligible compared to that used for the finite element model. Such observations demonstrate that the simplified model is accurate and effective. Copyright © 2013 John Wiley & Sons, Ltd.
Comparison of live‐trapping and noninvasive genetic sampling to assess patch occupancy by New England cottontail (Sylvilagus transitionalis) rabbits
Authors: Kilpatrick Howard J. , Goodie Travis J. , Kovach Adrienne I.
Published: September 2013

The New England cottontail (Sylvilagus transitionalis) is a species of high conservation priority in the northeastern United States and a candidate for federal listing under the Endangered Species Act. Eastern cottontails are abundantly distributed and similar in appearance to New England cottontails. Our objective was to compare cost, effort, and effectiveness of live‐trapping and noninvasive genetic monitoring for assessing patch occupancy by New England cottontail. We collected 113 tissue samples and 240 fecal pellets samples for diagnostic genetic testing to detect species presence and assess the proportion of samples consisted of New England and eastern cottontail on 5 study sites in Connecticut in 2008 and 2009. Both methods detected presence of New England cottontail at 4 of 5 sites. Overall proportion of DNA samples consisted of New England cottontail was similar between sampling methods (χ2 = 0.189, P = 0.664). However, species composition on individual sites was inconsistent between methods and no clear pattern of bias was discernible. Mean cost per DNA sample to collect and analyze was US$433 for tissue samples and US$33 for fecal pellets. Samples collected per person‐day of effort were 40 for fecal samples and 0.7 for tissue samples. Genetic monitoring via noninvasive fecal sampling was a low‐cost, time‐efficient method for assessing species occupancy, but development of an optimal sampling strategy is needed to evaluate composition and distributions of species on sympatrically occupied sites. © 2013 The Wildlife Society.