bluuebunny/crossref_metadata_2025 huggingface dataset:
The Student‐Teacher Shuttle Card for Japanese Dental Students Taking a Dental English Course
Authors: RODIS OMAR M. , KARIYA NAOYUKI , NISHIMURA MICHIKO , MATSUMURA SEISHI
Published: March 2011

There has been a noticeable change of curricula in specialized and technical courses offered in Japanese schools and universities. One of these is the integration of English for general and specific purposes in the dental curriculum. Although a number of studies have assessed the former, very few have assessed English for specific purposes education for dentistry in Japan. Further, studies that look into methods of facilitating its integration into the dental curriculum, what the course comprises, and the specific needs of students are therefore needed. Because Japanese students rarely participate actively in student‐teacher interaction, this article describes how the student‐teacher shuttle card, a type of journal, was used to identify students' specific satisfaction or needs and implications for improving course management. Consecutively used for 3 years in a dental school setting, freshmen students were able to convey their questions and opinions easily through the card. Entries from the card may be used to maintain, improve, or develop better teaching methods. They may also identify students who need more attention or who can be used as models for others during group discussions or practical exercises.
Influence of meteorology on PM10 trends and variability in Switzerland from 1991 to 2008
Authors: Barmpadimos I. , Hueglin C. , Keller J. , Henne S. , Prévôt A. S. H.
Published: March 2011

Abstract. Measurements of airborne particles with aerodynamic diameter of 10 μm or less (PM10) and meteorological observations are available from 13 stations distributed throughout Switzerland and representing different site types. The effect of all available meteorological variables on PM10 concentrations was estimated using Generalized Additive Models. Data from each season were treated separately. The most important variables affecting PM10 concentrations in winter, autumn and spring were wind gust, the precipitation rate of the previous day, the precipitation rate of the current day and the boundary layer depth. In summer, the most important variables were wind gust, Julian day and afternoon temperature. In addition, temperature was important in winter. A "weekend effect" was identified due to the selection of variable "day of the week" for some stations. Thursday contributes to an increase of 13% whereas Sunday contributes to a reduction of 12% of PM10 concentrations compared to Monday on average over 9 stations for the yearly data. The estimated effects of meteorological variables were removed from the measured PM10 values to obtain the PM10 variability and trends due to other factors and processes, mainly PM10 emissions and formation of secondary PM10 due to trace gas emissions. After applying this process, the PM10 variability was much lower, especially in winter where the ratio of adjusted over measured mean squared error was 0.27 on average over all considered sites. Moreover, PM10 trends in winter were more negative after the adjustment for meteorology and they ranged between −1.25 μg m−3 yr−1 and 0.07 μg m−3 yr−1. The adjusted trends for the other seasons ranged between −1.34 μg m−3 yr−1 and −0.26 μg m−3 yr−1 in spring, −1.40 μg m−3 yr−1 and −0.28 μg m−3 yr−1 in summer and −1.28 μg m−3 yr−1 and −0.11 μg m−3 yr−1 in autumn. The estimated trends of meteorologically adjusted PM10 were in general non-linear. The two urban street sites considered in the study, Bern and Lausanne, experienced the largest reduction in measured and adjusted PM10 concentrations. This indicates a verifiable effect of traffic emission reduction strategies implemented during the past two decades. The average adjusted yearly trends for rural, urban background and urban street stations were −0.37, −0.53 and −1.2 μg m−3 yr−1 respectively. The adjusted yearly trends for all stations range from −0.15 μg m−3 yr−1 to −1.2 μg m−3 yr−1 or −1.2% yr−1 to −3.3% yr−1.
Radiative impact of mineral dust on monsoon precipitation variability over West Africa
Authors: Zhao C. , Liu X. , Ruby Leung L. , Hagos S.
Published: March 2011

Abstract. The radiative forcing of dust and its impact on precipitation over the West Africa monsoon (WAM) region is simulated using a coupled meteorology and aerosol/chemistry model (WRF-Chem). During the monsoon season, dust is a dominant contributor to aerosol optical depth (AOD) over West Africa. In the control simulation, on 24-h domain average, dust has a cooling effect (−6.11 W m−2) at the surface, a warming effect (6.94 W m−2) in the atmosphere, and a relatively small TOA forcing (0.83 W m−2). Dust modifies the surface energy budget and atmospheric diabatic heating. As a result, atmospheric stability is increased in the daytime and reduced in the nighttime, leading to a reduction of late afternoon precipitation by up to 0.14 mm/h (25%) and an increase of nocturnal and early morning precipitation by up to 0.04 mm/h (45%) over the WAM region. Dust-induced reduction of diurnal precipitation variation improves the simulated diurnal cycle of precipitation when compared to measurements. However, daily precipitation is only changed by a relatively small amount (−0.17 mm/day or −4%). The dust-induced change of WAM precipitation is not sensitive to interannual monsoon variability. On the other hand, sensitivity simulations with weaker to stronger absorbing dust (in order to represent the uncertainty in dust solar absorptivity) show that, at the lower atmosphere, dust longwave warming effect in the nighttime surpasses its shortwave cooling effect in the daytime; this leads to a less stable atmosphere associated with more convective precipitation in the nighttime. As a result, the dust-induced change of daily WAM precipitation varies from a significant reduction of −0.52 mm/day (−12%, weaker absorbing dust) to a small increase of 0.03 mm/day (1%, stronger absorbing dust). This variation originates from the competition between dust impact on daytime and nighttime precipitation, which depends on dust shortwave absorption. Dust reduces the diurnal variation of precipitation regardless of its absorptivity, but more reduction is associated with stronger absorbing dust.
A hydrologic post-processor for ensemble streamflow predictions
Authors: Zhao L. , Duan Q. , Schaake J. , Ye A. , Xia J.
Published: March 2011

Abstract. This paper evaluates the performance of a statistical post-processor for imperfect hydrologic model forecasts. Assuming that the meteorological forecasts are well-calibrated, we employ a "General Linear Model (GLM)" to post-process simulations produced by a hydrologic model. For a particular forecast date, the observations and simulations from an "analysis window" and hydrologic model forecasts for a "forecast window", the GLM Post-Processor (GLMPP) is used to produce an ensemble of predictions of the streamflow observations that will occur during the "forecast window". The objectives of the GLMPP are to: (1) preserve any skill in the original hydrologic ensemble forecast; (2) correct systematic model biases; (3) retain the equal-likelihood assumption for the ensemble; (4) preserve temporal scale dependency relationships in streamflow hydrographs and the uncertainty in the predictions; and, (5) produce reliable ensemble predictions. Observed and simulated daily streamflow data from the Second Workshop on Model Parameter Estimation Experiment (MOPEX) are used to test how well these objectives are met when the GLMPP is applied to ensemble hydrologic forecasts driven by well calibrated meteorological forecasts. A 39-year hydrologic dataset from the French Broad basin is split into calibration and verification periods. The results show that the GLMPP built using data from the calibration period removes the mean bias when applied to hydrologic model simulations from both the calibration and verification periods. Probability distributions of the post-processed model simulations are shown to be closer to the climatological probability distributions of observed streamflow than the distributions of the unadjusted simulated flows. A number of experiments with different GLMPP configurations were also conducted to examine the effects of different configurations for forecast and analysis window lengths on the robustness of the results.
Retrieval of tropospheric water vapour by using spectra of a 22 GHz radiometer
Authors: Bleisch R. , Kämpfer N. , Haefele A.
Published: March 2011

Abstract. In this paper, we present an approach to retrieve tropospheric water vapour profiles from pressure broadened emission spectra at 22 GHz, measured by a ground based microwave radiometer. Classical microwave instruments concentrating on the troposphere observe several channels in the center and the wings of the water vapour line (20–30 Ghz), whereas our retrieval approach uses spectra with a bandwidth of 1 GHz and a high resolution around the center of the 22 GHz water vapour line. The retrieval is sensitive up to 7 km with a vertical resolution of 3–5 km. Validations with profiles from operational balloon soundings, performed at Payerne, 40 km away from the radiometer location, showed a good agreement up to 7 km with a correlation of above 0.7. The retrievals shows a wet bias of 10–20% compared to the sounding.
How to link soil C pools with CO2 fluxes?
Authors: Kuzyakov Y.
Published: March 2011

Abstract. Despite the importance of carbon (C) pools and CO2 fluxes in terrestrial ecosystems and especially in soils, as well as many attempts to assign fluxes to specific pools, this challenge remains unsolved. Interestingly, scientists investigating pools are not closely linked with scientists studying fluxes. This mini-review therefore focused on experimental approaches enabling soil C pools to be linked with CO2 flux from the soil. The background, advantages and shortcomings of uncoupled approaches (measuring only pools or fluxes) and of coupled approaches (measuring both pools and fluxes) were evaluated and their prerequisites – steady state of pools and isotopic steady state – described. The uncoupled approaches include: (i) monitoring the decrease of C pools in long-term fallow bare soil lacking C input over decades, (ii) analyzing components of CO2 efflux dynamics by incubating soil without new C input over months or a few years, and (iii) analyzing turnover rates of C pools based on their 13C and 14C isotopic signature. The uncoupled approaches are applicable for non steady state conditions only and have limited explanatory power. The more advantageous coupled approaches partition simultaneously pools and fluxes and are based on one of three types of changes in the isotopic signature of input C compared to soil C: (i) abrupt permanent, (ii) gradual permanent, and (iii) abrupt temporary impacts. I show how the maximal sensitivity of the approaches depends on the differences in the isotopic signature of pools with fast and slow turnover rates. The promising coupled approaches include: (a) &delta13C of C pools and CO2 efflux from soil after C3/C4 vegetation changes or in FACE experiments (both corresponding to continuous labeling), (b) addition of 13C or 14C labeled organics (corresponding to pulse labeling), and (c) bomb-14C. I show that physical separation of soil C pools is not a~prerequisite to estimate pool size or to link pools with fluxes. The future challenges include combining two or more promising approaches to elucidate more than two C sources for CO2 fluxes, and linking scientific communities investigating the pools with those investigating the fluxes.
Application of δ13C and δ15N isotopic signatures of organic matter fractions sequentially separated from adjacent arable and forest soils to identify carbon stabilization mechanisms
Authors: Kayler Z. E. , Kaiser M. , Gessler A. , Ellerbrock R. H. , Sommer M.
Published: March 2011

Abstract. Identifying the chemical mechanisms behind soil carbon bound in organo-mineral complexes is necessary to determine the degree to which soil organic carbon is stabilized belowground. We used the δ13C and δ15N isotopic signatures from two organic matter (OM) fractions from soil to identify the likely binding mechanisms involved. We used OM fractions hypothesized to contain carbon stabilized through organo-mineral complexes: (1) OM separated chemically with sodium pyrophosphate (OM(PY)) and (2) OM stabilized in microstructures found in the chemical extraction residue (OM(ER)). Furthermore, because the OM fractions were separated from five different soils with paired forest and arable land use histories, we could address the impact of land use change on carbon binding and processing mechanisms within these soils. We used partial least squares regression to analyze patterns in the isotopic signature of OM with established proxies of different binding mechanisms. Parsing soil OM into different fractions is a systematic method of dissection, however, we are primarily interested in how OM is bound in soil as a whole, requiring a means of re-assembly. Thus, we implemented the recent zonal framework described by Kleber et al. (2007) to relate our findings to undisturbed soil. The δ15N signature of OM fractions served as a reliable indicator for microbial processed carbon in both arable and forest land use types. The δ13C signature of OM fractions in arable sites did not correlate well with proxies of soil mineral properties while a consistent pattern of enrichment was seen in the δ13C of OM fractions in the forest sites. We found a significant difference in δ13C of pooled OM fractions between the forest and arable land use type although it was relatively small (<1‰). We found different binding mechanisms predominate in each land use type. The isotopic signatures of OM fractions from arable soils were highly related to the clay and silt size particles amount while organic matter not directly bound to mineral surfaces in the contact zone was involved in cation bonding with Ca. In forest soils, we found a relationship between isotopic signatures of OM(PY) and the ratio of soil organic carbon content to soil surface area (SOC/SSA). For arable soils, the formation of OM(PY)-Ca-mineral associations seems to be a relevant OM stabilization mechanism while the OM(PY) of forest soils seems to be separated from layers of slower exchange not directly attached to mineral surfaces. This means there is a potential to build multiple OM layers on mineral particles in the arable soil and thus the potential for carbon accumulation.
The effect of a dynamic background albedo scheme on Sahel/Sahara precipitation during the mid-Holocene
Authors: Vamborg F. S. E. , Brovkin V. , Claussen M.
Published: March 2011

Abstract. We have implemented a new albedo scheme that takes the dynamic behaviour of the surface below the canopy into account, into the land-surface scheme of the MPI-ESM. The standard (static) scheme calculates the seasonal canopy albedo as a function of leaf area index, whereas the background albedo is a gridbox constant derived from satellite measurements. The new (dynamic) scheme additionally models the background albedo as a slowly changing function of organic matter in the ground and of litter and standing dead biomass covering the ground. We use the two schemes to investigate the interactions between vegetation, albedo and precipitation in the Sahel/Sahara for two time-slices: pre-industrial and mid-Holocene. The dynamic scheme represents the seasonal cycle of albedo and the correspondence between annual mean albedo and vegetation cover in a more consistent way than the static scheme. It thus gives a better estimate of albedo change between the two time periods. With the introduction of the dynamic scheme, precipitation is increased by 30 mm yr−1 for the pre-industrial simulation and by about 80 mm yr−1 for the mid-Holocene simulation. The present-day dry bias in the Sahel of standard ECHAM5 is thus reduced and the sensitivity of precipitation to mid-Holocene external forcing is increased by around one third. The locations of mid-Holocene lakes, as estimated from reconstructions, lie south of the modelled desert border in both mid-Holocene simulations. The magnitude of simulated rainfall in this area is too low to fully sustain lakes, however it is captured better with the dynamic scheme. The dynamic scheme leads to increased vegetation variability in the remaining desert region, indicating a higher frequency of green spells, thus reaching a better agreement with the vegetation distribution as derived from pollen records.
Hydropedological insights when considering catchment classification
Authors: Bouma J. , Droogers P. , Sonneveld M. P. W. , Ritsema C. J. , Hunink J. E. , Immerzeel W. W. , Kauffman S.
Published: March 2011

Abstract. Soil classification systems are analysed in relation to the functioning and characterisation of catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. However, such classifications are based on permanent characteristics as formed by the soil forming factors over often very long periods of time and this does not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards functional characterization of soils as is illustrated for recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous field soils with varying soil structures during the year and the suggestion is made to first focus on improving simulation of catchment hydrology, incorporating hydropedological expertise, before embarking on a classification effort which involves major input of time and involves the risk of distraction. In doing so, we advise to also define other characteristics for catchment performance than the traditionally measured discharge rates.
Assessment of debris-flow susceptibility at medium-scale in the Barcelonnette Basin, France
Authors: Kappes M. S. , Malet J.-P. , Remaître A. , Horton P. , Jaboyedoff M. , Bell R.
Published: March 2011

Abstract. Debris flows are among the most dangerous processes in mountainous areas due to their rapid rate of movement and long runout zone. Sudden and rather unexpected impacts produce not only damages to buildings and infrastructure but also threaten human lives. Medium- to regional-scale susceptibility analyses allow the identification of the most endangered areas and suggest where further detailed studies have to be carried out. Since data availability for larger regions is mostly the key limiting factor, empirical models with low data requirements are suitable for first overviews. In this study a susceptibility analysis was carried out for the Barcelonnette Basin, situated in the southern French Alps. By means of a methodology based on empirical rules for source identification and the empirical angle of reach concept for the 2-D runout computation, a worst-case scenario was first modelled. In a second step, scenarios for high, medium and low frequency events were developed. A comparison with the footprints of a few mapped events indicates reasonable results but suggests a high dependency on the quality of the digital elevation model. This fact emphasises the need for a careful interpretation of the results while remaining conscious of the inherent assumptions of the model used and quality of the input data.
The imbalance of glaciers after disintegration of Larsen-B ice shelf, Antarctic Peninsula
Authors: Rott H. , Müller F. , Nagler T. , Floricioiu D.
Published: March 2011

Abstract. The outlet glaciers to the embayment of the Larsen-B Ice Shelf started to accelerate soon after the ice shelf disintegrated in March 2002. We analyse high resolution radar images of the TerraSAR-X satellite, launched in June 2007, to map the motion of outlet glaciers in detail. The frontal velocities are used to estimate the calving fluxes for 2008/2009. As reference for pre-collapse conditions, when the glaciers were in balanced state, the ice fluxes through the same gates are computed using ice motion maps derived from interferometric data of the ERS-1/ERS-2 satellites in 1995 and 1999. Profiles of satellite laser altimetry from ICESat, crossing the terminus of several glaciers, indicate considerable glacier thinning between 2003 and 2007/2008. This is taken into account for defining the calving cross sections. The difference between the pre- and post-collapse fluxes provides an estimate on the mass imbalance. For the Larsen-B embayment the 2008 mass deficit is estimated at 4.34 ± 1.64 Gt a−1, significantly lower than previously published values. The ice flow acceleration follows a similar pattern on the various glaciers, gradually decreasing in magnitude with distance upstream from the calving front. This suggests stress perturbation at the glacier front being the main factor for acceleration. So far there are no signs of slow-down indicating that dynamic thinning and frontal retreat will go on.
Seeing Eye to Eye: The Key to Reducing Catheter Use
Authors: Chaudhry Maryum , Bhola Cynthia , Joarder Mohammad , Zimmerman Deborah , Quinan Patty , Mendelssohn David , Lok Charmaine E.
Published: March 2011

Purpose

Hemodialysis central venous catheters (CVCs) are increasingly used, despite a prevalence target of <10%. The primary aim of our study was to understand why patients persistently use their CVCs.

Methods

A multicenter prospective observational study surveyed 322 patients and their vascular access coordinators (VACs) to determine the reasons patients use CVCs. Their responses were compared using multirater kappa statistics. An 18–month follow-up survey was applied to a subgroup of patients consistently using their CVCs, and correlated with the VACs' and patients' previous responses. Predictive associations for specific reasons for CVC use were explored.

Results

Patients indicated “non-medical” reasons (34.8%), having previously failed fistulas/grafts (25.8%), and fear of disfiguration (11.5%) as the main reasons for CVC use. The VAC was in agreement with the patient 16.5% of the time, in partial agreement 37.0%, and in disagreement 46.5%. Twelve percent of patients indicated a desire to change their CVC, yet the VAC was unaware of this 78% of the time.

Conclusions

The primary reasons patients use CVCs are “non-medical” followed by concerns with the complications and esthetic appearance associated with fistulas/grafts. The significant discordance between the reasons the patients give and the VACs view of patient reasons for CVC use suggests a gap in knowledge, understanding, or communication between patients and their VACs. Timely predialysis education to address this gap and realistic targets are necessary to reduce CVC prevalence.
Strategies to Design Bipolar Small Molecules for OLEDs: Donor‐Acceptor Structure and Non‐Donor‐Acceptor Structure
Authors: Duan Lian , Qiao Juan , Sun Yongduo , Qiu Yong
Published: March 2011

Organic light‐emitting diodes (OLEDs) have attracted great attention because of their potential applications in full‐color displays and solid‐state lights. In the continual effort to search for ideal materials for OLEDs, small molecules with bipolar transporting character are extremely attractive as they offer the possibility to achieve efficient and stable OLEDs even in a simple single‐layer device. In this Research News, we review the two design strategies of bipolar materials for OLEDs: molecules with or without donor‐acceptor structures. The correlation between the experimental results and theoretical calculations of some of the materials is also discussed.
Molecular Beam Epitaxial Growth of Topological Insulators
Authors: Chen Xi , Ma Xu‐Cun , He Ke , Jia Jin‐Feng , Xue Qi‐Kun
Published: March 2011

With the molecular beam epitaxy technique, layer‐by‐layer growth of atomically flat topological insulator Bi2Te3 and Bi2Se3 thin films has been realized on Si(111) and graphene substrates, respectively. The growth criteria by which intrinsic topological insulators can readily be obtained is established. By using in situ angle‐resolved photoemission spectroscopy and scanning tunneling microscopy measurements, the band structure and surface morphology of Bi2Te3 and Bi2Se3 thin films of different thickness can be studied. Molecular beam epitaxy technique was shown to not only provide an excellent method to prepare high quality topological insulators but show possibilities of engineering their electronic and spin structures as well, which is of significant importance for potential applications of topological insulators based on well‐developed Si technology.
Bimetallic Nanocrystals: Bimetallic Nanocrystals: Liquid‐Phase Synthesis and Catalytic Applications (Adv. Mater. 9/2011)
Authors: Wang Dingsheng , Li Yadong
Published: March 2011

Bimetallic nanocrystals (NCs) with core/shell, heterostructure, or inter­metallic and alloyed structures are emerging as more important materials than monometallic NCs. They are expected to display not only a combination of the properties associated with two distinct metals, but also new properties and capabilities due to a synergy between the two metals. More importantly, bimetallic NCs usually show composition‐dependent surface structure and atomic segregation behavior, and therefore more interesting applied potentials in various fields including electronics, engineering, and catalysis. Compared with monometallic NCs, preparation of bimetallic NCs is much more complicated and difficult to be achieved. In recent years, researchers from many groups have made great efforts in this area. This review highlights the recent progress in the chemical synthesis of bimetallic NCs. The control over morphology, size, composition, and structure of bimetallic NCs as well as the exploration of their properties and applications are discussed.
Migrant farmworkers' housing conditions across an agricultural season in North Carolina
Authors: Vallejos Quirina M. , Quandt Sara A. , Grzywacz Joseph G. , Isom Scott , Chen Haiying , Galván Leonardo , Whalley Lara , Chatterjee Arjun B. , Arcury Thomas A.
Published: March 2011

Background

Several studies have documented poor housing conditions for farmworkers but none has focused on migrant farmworker housing, which is often provided as a condition of employment. Farmworker housing quality is regulated, but little documentation exists of compliance with regulations.

Methods

A 2007 survey of 43 randomly selected farmworker camps and a 2008 survey of 27 camps randomly selected from the 2007 sample documented housing conditions via interviewer administered questionnaire and housing checklist.

Results

Substandard conditions are common in migrant housing. All camps had at least one exterior housing problem; 93% had at least one interior problem. Housing conditions worsen across the agricultural season. Characteristics including no residents with H2A visa and 11 or more residents are associated with poorer conditions.

Conclusions

Housing standards are not adequately enforced. An increase in post‐occupancy inspections and targeting camps with characteristics that place them at increased risk for substandard conditions are recommended. Am. J. Ind. Med. 54:533–544, 2011. © 2011 Wiley‐Liss, Inc.
Effect of alkyl silicone oil on the compatibility of polypropylene/microencapsulated ammonium polyphosphate composites
Authors: Ma Zhi‐Ling , Lu Guang‐Yu
Published: March 2011

The effect of alkyl silicone oil (ASO) as a compatibilizer on the compatibility of polypropylene (PP)/microencapsulated ammonium polyphosphate (MAPP) composites was investigated. The data from the mechanical tests showed that when 0.25% ASO was added, the tensile strength of the PP/MAPP/ASO composites increased approximately 41% compared with that of the PP/MAPP composite. The scanning electron microscopy results illustrate that ASO improved the interfacial adhesion between MAPP and PP. Polarized optical microscopy and X‐ray diffraction demonstrated that ASO decreased the agglomeration of MAPP and made MAPP disperse homogeneously in PP. Flow tests and IR spectroscopy indicated that ASO played the role of lubricant in PP/MAPP, and the flow behavior of composites in the melt was that of a pseudoplastic liquid, in which MAPP interacted with ASO by molecular interaction. All of the investigations showed that a suitable amount of ASO improved the compatibility of the PP/MAPP composite. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Stable crosslinked vinyl‐addition‐type polynorbornene graft copolymer proton‐exchange membranes
Authors: Liu Shufang , Chen Yiwang , He Xiaohui , Chen Lie , Zhou Weihua
Published: March 2011

The graft copolymer poly(butoxymethylene norbornene‐co‐norbornenemethylene bromoisobutyrylate) [P(BN/NB)]‐graft‐poly(hydroxyethyl methacrylate) (PHEMA) was synthesized by the atom transfer radical polymerization of 2‐hydroxyethyl methacrylate from a copolymer prepared by two functional norbornene monomers via a vinyl addition mechanism. The graft copolymer P(BN/NB)‐g‐PHEMA was further crosslinked with 4,5‐imidazole dicarboxylic acid (IDA) and then doped with phosphoric acid (H3PO4) to form imidazole–H3PO4 complexes. The results show that the polynorbornene backbone and crosslinked micromorphology produced low methanol permeability in the membranes (from 1.5 × 10−7 to 3.8 × 10−6 cm2/s) and endowed the membranes with good mechanical properties (with elastic modulus values of 692.7 to 159.7 MPa, elongation at break values from 2.7 to 22.7%, and tensile strength at break values from 14.4 to 5.5 MPa) and excellent thermal stability (up to 280°C). Furthermore, the proton conductivities of the membranes increased with increasing temperature and increasing content of IDA/H3PO4 in the membranes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Theoretical Analysis of the Detailed Mechanism of Native Chemical Ligation Reactions
Authors: Wang Chen , Guo Qing‐Xiang , Fu Yao
Published: March 2011

The method of native chemical ligation between an unprotected peptide α‐thioester and an N‐terminal cysteine–peptide to give a native peptide in aqueous solution is one of the most effective peptide ligation methods. In this work, a systematic theoretical study was carried out to fully understand the detailed mechanism of ligation. It was found that for the conventional native chemical ligation reaction between a peptide thioalkyl ester and a cysteine in combination with an added aryl thiol as catalyst, both the thiol‐thioester exchange step and the transthioesterification step proceed by an anionic concerted SN2 displacement mechanism, whereas the intramolecular rearrangement proceeds by an addition–elimination mechanism, and the rate‐limiting step is the thiol‐thioester exchange step. The theoretical method was then extended to study the detailed mechanism of the auxiliary‐mediated peptide ligation between a peptide thiophenyl ester and an N‐2‐mercaptobenzyl peptide in which both the thiol‐thioester exchange step and intramolecular acyl‐transfer step proceed by a concerted SN2‐type displacement mechanism. The energy barrier of the thiol‐thioester exchange step depends on the side‐chain steric hindrance of the C‐terminal amino acid, whereas that of the acyl‐transfer step depends on the side‐chain steric hindrance of the N‐terminal amino acid.
A de novo 1.5 Mb microdeletion on chromosome 14q23.2‐23.3 in a patient with autism and spherocytosis
Authors: Griswold Anthony J. , Ma Deqiong , Sacharow Stephanie J. , Robinson Joycelyn L. , Jaworski James M. , Wright Harry H. , Abramson Ruth K. , Lybæk Helle , Øyen Nina , Cuccaro Michael L. , Gilbert John R. , Pericak‐Vance Margaret A.
Published: March 2011

Autism is a neuro‐developmental disorder characterized by deficits in social interaction and communication as well as restricted interests or repetitive behaviors. Cytogenetic studies have implicated large chromosomal aberrations in the etiology of approximately 5–7% of autism patients, and the recent advent of array‐based techniques allows the exploration of submicroscopic copy number variations (CNVs). We genotyped a 14‐year‐old boy with autism, spherocytosis and other physical dysmorphia, his parents, and two non‐autistic siblings with the Illumina Human 1M Beadchip as part of a study of the molecular genetics of autism and determined copy number variants using the PennCNV algorithm. We identified and validated a de novo 1.5 Mb microdeletion of 14q23.2‐23.3 in our autistic patient. This region contains 15 genes, including spectrin beta (SPTB), encoding a cytoskeletal protein previously associated with spherocytosis, methylenetetrahydrofolate dehydrogenase 1 (MTHFD1), a folate metabolizing enzyme previously associated with bipoloar disorder and schizophrenia, pleckstrin homology domain‐containing family G member 3 (PLEKHG3), a guanide nucleotide exchange enriched in the brain, and churchill domain containing protein 1 (CHURC1), homologs of which regulate neuronal development in model organisms. While a similar deletion has previously been reported in a family with spherocytosis, severe learning disabilities, and mild mental retardation, this is the first implication of chr14q23.2‐23.3 in the etiology of autism and points to MTHFD1, PLEKHG3, and CHURC1 as potential candidate genes contributing to autism risk. Autism Res 2011,4:221–227. © 2011 International Society for Autism Research, Wiley Periodicals, Inc.
ASIS&T new leaders award
Authors: Schwartz Candy
Published: March 2011

Starting with the 2010 Annual Meeting, ASIS&T established the New Leaders Award to recognize outstanding up‐and‐coming information scientists. The recipients for 2010 were Andrea Baer, Laura Christopherson, Alex Garnett, Margaret Gross, Thomas Heverin, Tina Jayroe, Sara Mooney and Denise Pasquinelli. Award recipients have been active in local ASIS&T chapter activities, and many were prompted by mentors to apply for the recognition. To further their leadership, they were expected to participate in a leadership activity supporting the Annual Meeting and to establish personal leadership goals for the future. These outstanding new leaders have taken on responsibilities for promoting and sustaining their SIGs, building chapters and recruiting members, developing webinars and workshops and building networking groups of information scientists with similar interests.
Applying Model Predictive Control to Dividing Wall Columns
Authors: Buck C. , Hiller C. , Fieg G.
Published: March 2011

The technology of dividing wall columns can offer enormous energy savings compared to common distillation columns and configurations. The technology of model predictive control is also advantageous since such a controller minimizes the future deviation of the predicted controlled variable from the reference point. The practical application of model predictive controllers for dividing wall columns is still limited due to limited experience with high interactions among the process variables. The scope of this work is the development and analysis of a method for the design of model predictive controllers for dividing wall columns. An experimental investigation verifies the practicability of the applied approach. The methods generated are transferable to other applications. Thus, the industrial acceptance of model predictive controllers for dividing wall columns is enhanced.
Titanium Containing Monocrystals of Ruby and Sapphire
Authors: Bogdanov B. I. , Markovska I. G. , Hristov Y. , Georgiev D. P.
Published: March 2011

The aim of this study was to obtain synthetic corundum monocrystals, called star ruby and star sapphire, using the Verneuil flame fusion process. The corundum monocrystals are known to possess an unusual complex of properties which determine their increasing application in different areas of jewelry and technology The optimal temperature‐time parameters during obtaining the starting mixtures which contribute to the synthesis of high quality corundum monocrystals were established. The corundum monocrystals obtained are equivalent to the natural gemstones – rubies and sapphires.
Inline Analyzing of Industrial Crystallization Processes by an Innovative Ultrasonic Probe Technique
Authors: Pertig D. , Buchfink R. , Petersen S. , Stelzer T. , Ulrich J.
Published: March 2011

The mean particle size and suspension density of industrial ammonium sulfate and urea crystals were measured by a single ultrasound sensor in a saturated solution at only one frequency. The information on ultrasound velocity and attenuation were combined and related to characteristic properties of the solid phase of suspensions. By model identification, a correlation between the measured signals and mean particle size as well as suspension density were evaluated and verified by additional experiments. The measurements with different particle size fractions and different suspension densities up to 40 wt‐% were carried out isothermally. The approach of coupled ultrasound velocity and attenuation provides a simple technique for inline process control on the liquid and solid state of a suspension process like solution crystallization only by a single measurement device.
Shedding New Light on ZnCl2‐Mediated Addition Reactions of Grignard Reagents to Ketones: Structural Authentication of Key Intermediates and Diffusion‐Ordered NMR Studies
Authors: Armstrong David R. , Clegg William , García‐Alvarez Pablo , McCall Matthew D. , Nuttall Lorraine , Kennedy Alan R. , Russo Luca , Hevia Eva
Published: March 2011

Building on recent advances in synthesis showing that the addition of inorganic salts to Grignard reagents can greatly enhance their performance in alkylation reactions to ketones, this study explores the reactions of EtMgCl with benzophenone in the presence of stoichiometric or catalytic amounts of ZnCl2 with the aim of furthering the understanding of the role and constitution of the organometallic species involved in these transformations. Investigations into the metathesis reactions of three molar equivalents of EtMgCl with ZnCl2 led to the isolation and characterisation (X‐ray crystallography and 1H and 13C NMR spectroscopy) of novel magnesium “zinc‐rich” zincate [{(THF)6Mg2Cl3}+{Zn2Et5}−] (1), whose complicated constitution in THF solutions was assessed by variable‐temperature 1H DOSY NMR studies. Compound 1 reacted with one equivalent of benzophenone to yield magnesium magnesiate [{(THF)6Mg2Cl3}+{Mg2(OC(Et)Ph2)2Cl3(THF)}−] (3), whose structure was determined by X‐ray crystallography. 1H NMR monitoring of this reaction showed two equivalents of ZnEt2 formed as a co‐product, which together with the “magnesium only constitution” of 3 provides experimental insights into how zinc can be efficiently recycled in these reactions, and therefore used catalytically. The chemoselectivity of this reaction can be rationalised in terms of the synergic effect of magnesium and zinc and contrasts with the results obtained when benzophenone was allowed to react with EtMgCl in the absence of ZnCl2, where the reduction of the ketone takes place preferentially. The reduction product [{(THF)5Mg3Cl4{OC(H)Ph(CF3)}2] (4) obtained from the reaction of EtMgCl with 2,2,2‐trifluoroacetophenone was established by X‐ray crystallography and multinuclear (1H, 13C and 19F) NMR spectroscopy. Compounds 3 and 4 exhibit new structural motifs in magnesium chemistry having MgCl2 integrated within their constitution, which highlights the new role of this inorganic salt in providing structural support for the newly generated alkoxide ligand.
Pseudo‐Bimolecular [2+2] Cycloaddition Studied by Time‐Resolved Photoelectron Spectroscopy
Authors: Brogaard Rasmus Y. , Boguslavskiy Andrey E. , Schalk Oliver , Enright Gary D. , Hopf Henning , Raev Vitaly A. , Jones Peter G. , Thomsen Ditte L. , Sølling Theis I. , Stolow Albert
Published: March 2011

The first study of pseudo‐bimolecular cycloaddition reaction dynamics in the gas phase is presented. We used femtosecond time‐resolved photoelectron spectroscopy (TRPES) to study the [2+2] photocycloaddition in the model system pseudo‐gem‐divinyl[2.2]paracyclophane. From X‐ray crystal diffraction measurements we found that the ground‐state molecule can exist in two conformers; a reactive one in which the vinyl groups are immediately situated for [2+2] cycloaddition and a nonreactive conformer in which they point in opposite directions. From the measured S1 lifetimes we assigned a clear relation between the conformation and the excited‐state reactivity; the reactive conformer has a lifetime of 13 ps, populating the ground state through a conical intersection leading to [2+2] cycloaddition, whereas the nonreactive conformer has a lifetime of 400 ps. Ab initio calculations were performed to locate the relevant conical intersection (CI) and calculate an excited‐state [2+2] cycloaddition reaction path. The interpretation of the results is supported by experimental results on the similar but nonreactive pseudo‐para‐divinyl[2.2]paracyclophane, which has a lifetime of more than 500 ps in the S1 state.
Liquid chromatographic resolution of 3‐amino‐1,4‐benzodiazepin‐2‐one derivatives on various Pirkle‐type chiral stationary phases
Authors: Park Je Young , Cho Hwan Sun , Hyun Myung Ho
Published: March 2011

The two enantiomers of N‐acyl amide and N‐ureide derivatives of 3‐amino‐5‐phenyl‐1,4‐benzodiazepin‐2‐ones, which have been known to show anti‐respiratory syncytial virus (RSV) activity, were resolved on seven different Pirkle‐type chiral stationary phases (CSPs) with the use of 10% isopropyl alcohol in hexane as a mobile phase. Among the seven Pirkle‐type CSPs, the one based on (S)‐leucine derivative named as N‐Phe‐L‐Leu was found to be most successful, the separation factors (α) and the resolutions (RS) for seven analytes being in the range of 1.78–4.21 and 5.94–15.08, respectively. By resolving N‐benzyloxycarbonyl derivatives of 3‐amino‐5‐phenyl(or 5‐methyl)‐1,4‐benzodiazepin‐2‐ones on Pirkle‐type CSPs, the phenyl ring at the 5‐position and the NH hydrogen at the 1‐position of analytes were found to play an important role in the chiral recognition. Chirality, 2011. © 2011 Wiley Periodicals, Inc.
The domain organization of the bacterial intermediate filament‐like protein crescentin is important for assembly and function
Authors: Cabeen Matthew T. , Herrmann Harald , Jacobs‐Wagner Christine
Published: March 2011

Crescentin is a bacterial filament‐forming protein that exhibits domain organization features found in metazoan intermediate filament (IF) proteins. Structure‐function studies of eukaryotic IFs have been hindered by a lack of simple genetic systems and easily quantifiable phenotypes. Here we exploit the characteristic localization of the crescentin structure along the inner curvature of Caulobacter crescentus cells and the loss of cell curvature associated with impaired crescentin function to analyze the importance of the domain organization of crescentin. By combining biochemistry and ultrastructural analysis in vitro with cellular localization and functional studies, we show that crescentin requires its distinctive domain organization, and furthermore that different structural elements have distinct structural and functional contributions. The head domain can be functionally subdivided into two subdomains; the first (amino‐terminal) is required for function but not assembly, while the second is necessary for structure assembly. The rod domain is similarly required for structure assembly, and the linker L1 appears important to prevent runaway assembly into nonfunctional aggregates. The data also suggest that the stutter and the tail domain have critical functional roles in stabilizing crescentin structures against disassembly by monovalent cations in the cytoplasm. This study suggests that the IF‐like behavior of crescentin is a consequence of its domain organization, implying that the IF protein layout is an adaptable cytoskeletal motif, much like the actin and tubulin folds, that is broadly exploited for various functions throughout life from bacteria to humans. © 2011 Wiley‐Liss, Inc.
Hematology/oncology fellows' training in palliative care
Authors: Buss Mary K. , Lessen David S. , Sullivan Amy M. , Von Roenn Jamie , Arnold Robert M. , Block Susan D.
Published: March 2011

BACKGROUND:

Palliative care is recognized as integral to the practice of oncology, yet many oncologists report inadequate training in critical palliative care domains, such as symptom management, psychosocial care, and communication skills. The authors of this report sought to assess the quantity and quality of palliative care education within oncology fellowships.

METHODS:

Second‐year oncology fellows completed a 104‐item survey that was modified and adapted from a national survey of medical students and residents. Items allowed comparison between palliative care and nonpalliative care topics.

RESULTS:

Of 402 eligible fellows, 63.2% responded (n = 254). Respondents were: 52% men, 62% Caucasian, and 64% US medical school graduates. Twenty‐six percent had completed a palliative care rotation. Fellows rated the overall quality of fellowship teaching more highly than teaching on palliative care (3.7 v 3.0 on a 1‐5 scale; t = 10.2; P < .001). Rates of being observed (81%) and receiving feedback (80%) on an end‐of‐life communication skill were high. Psychosocial needs of patients received some attention: Fifty‐seven percent of fellows reported that they were conveyed as a core competency, but only 32% of fellows received explicit education on assessing and managing depression at the end of life. Fellows rarely reported receiving explicit education on opioid rotation (33%). Fellows scored a median of 2 of 4 items that tested basic palliative care knowledge, and only 23% correctly performed an opioid conversion.

CONCLUSIONS:

Fellows rated the quality of palliative care education as inferior to overall oncology training and may benefit from more teaching on pain management, psychosocial care, and communication skills. Cancer 2011;. © 2011 American Cancer Society.
Improved survival in patients with lymph node‐positive gastric cancer who received preoperative radiation
Authors: Shridhar Ravi , Dombi George W. , Finkelstein Steven E. , Meredith Kenneth L. , Hoffe Sarah E.
Published: March 2011

BACKGROUND:

Several trials have been conducted to determine the feasibility of preoperative radiotherapy (RT) for gastric cancer. However, the absolute benefit from radiotherapy remains to be defined. In this study, the authors examined the use of preoperative RT (Pre‐RT) and postoperative RT (PORT) in patients with gastric cancer from the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS:

The overall survival of patients who had nonmetastatic, resected gastric cancer between 2000 and 2006 was analyzed from the SEER database. Kaplan‐Meier survival curves comparing Pre‐RT, PORT, and no RT (No‐RT) were analyzed using the log‐rank test. A multivariate analysis (MVA) was conducted using Cox proportional hazards regression.

RESULTS:

The authors identified 10,251 patients. There was no survival benefit for patients who received Pre‐RT or PORT compared with No‐RT patients for the entire cohort. Conversely, among lymph node‐positive patients, there was a significant survival benefit from both Pre‐RT and PORT compared with No‐RT (log‐rank test: PORT, P < .0001; Pre‐RT, P = .0261). The median survival and 5‐year overall survival among lymph node‐positive patients were 22 months and 24%, respectively, for Pre‐RT;29 months and 34%, respectively, for PORT; and 19 months and 20%, respectively, for No‐RT. MVA demonstrated that Pre‐RT, PORT, and removing ≥15 lymph nodes were independent predictors of improved survival, whereas tumor classification, lymph node status, tumor size, and tumor location were independent predictors of death.

CONCLUSIONS:

The current results supported the use of Pre‐RT in select patients with gastric cancer. However, additional trials will be needed to confirm these findings. Cancer 2011;. © 2011 American Cancer Society.