bluuebunny/crossref_metadata_2025_split huggingface dataset:
Both spontaneous Ins2+/− and streptozotocin‐induced type I diabetes cause bone loss in young mice
Authors: Coe Lindsay M. , Zhang Jing , McCabe Laura R. 
Published: August 2012

AbstractThe adolescent skeleton undergoes accelerated growth determining overall bone density, length, and quality. Diseases such as type 1 diabetes (T1D), most often diagnosed in adolescents, can alter bone processes and promote bone loss. Studies examining type 1 diabetic (T1D) bone pathologies typically utilize adult mice and rely on pharmacologic models such as streptozotocin (STZ)‐induced diabetic rodents. To test the effect of T1D on adolescent bone growth/density we used a novel juvenile genetic model (Ins2+/− mice) that spontaneously develop T1D at approximately 5 weeks of age and compared our findings with STZ‐induced T1D mice. Compared to controls, both Ins2+/− and STZ‐induced T1D mice displayed blood glucose levels greater than 300 mg/dl and reduced body, fat and muscle mass as well as femur trabecular bone density. STZ mice exhibited greater bone loss compared to Ins2+/− mice despite having lower blood glucose levels. Cortical bone was affected in STZ but not Ins2+/− mice. Osteocalcin serum protein and bone RNA levels decreased in both models. Consistent with studies in adult mice, STZ adolescent mice displayed increased marrow adiposity, however this was not observed in the Ins2+/− mice. Reduced femur length, decreased growth plate thickness and decreased collagen II expression in both model simplies impaired cartilage formation. In summary, both pharmacologic and spontaneous adolescent T1D mice demonstrated a bone synthesis and growth defect. STZ appears to cause a more severe phenotype. Thus, the Ins2+/− mouse could serve as a useful model to study adolescent T1D bone loss with fewer complications. J. Cell. Physiol. 228: 689–695, 2013. © 2012 Wiley Periodicals, Inc.
Low body mass index at 3 months following adjuvant chemoradiation affects survival of postoperative locally advanced oral cavity cancer patients
Authors: Chang Pei‐Hung , Wang Cheng‐Hsu , Huang Jen‐Seng , Lai Chien‐Hong , Wu Tsung‐Han , Lan Yii‐Jeng , Tsai Jason Chien‐Sheng , Chen Eric Yen‐Chao , Yang Shih‐Wei , Yeh Kun‐Yun 
Published: August 2012

AbstractObjectives/Hypothesis:To investigate the association between body mass index and outcomes such as recurrence and survival in postoperative locally advanced oral cavity cancer patients who underwent adjuvant chemoradiation.Study Design:Retrospective analysis of patient data and outcomes.Methods:We retrospectively analyzed the records of 61 stage III, IVA, and IVB oral cavity cancer patients who were treated with curative surgery and adjuvant chemoradiation between 2007 and 2009. Each patient's body mass index was recorded throughout the treatment duration and after its completion. The associations between demographic variables, body mass index, and survival outcomes were determined by univariate and multivariate analyses.Results:Overall, body mass index decreased throughout the chemoradiation period and reached the nadir at 3 months after completion of therapy. Univariate analysis showed that patients with body mass index <18.5 kg/m2 at 3 months after chemoradiation had significantly higher recurrence and decreased survival rates. Multivariate analysis confirmed that body mass index <18.5 kg/m2 at this time point is an independent predictor for recurrence (P = .039) and overall survival (P = .043).Conclusions:Early recurrence can be predicted by malnourished status 3 months after treatment completion. Malnourishment has significant negative effects on overall survival in locally advanced postoperative oral cavity cancer patients who are undergoing adjuvant chemoradiation. After therapy is completed, nutritional guidance and care should be continued for patients with this advanced disease.
Cobalt Ion‐Mediated Cysteine Detection With a Hyperbranched Conjugated Polyelectrolyte as a New Sensing Platform
Authors: Kim Daigeun , Jang Geunseok , Kim Jongho , Seo Seongwon , Park Won Ho , Lee Taek Seung 
Published: August 2012

AbstractA highly efficient colorimetric and fluorescence turn‐off probe for the sensitive and selective detection of the biologically important amino acid, cysteine (Cys), is demonstrated using a newly synthesized water‐soluble hyperbranched polymer (HP) containing sulfonic acid groups. The detection mechanism involves two steps: (i) the slight quenching of HP in the presence of Co2+ in advance; and (ii) the gradual quenching of the HP–Co2+ complex according to the concentration of Cys due to the absorption screening effect of the formation of the Cys‐Co2+ complex, which prevents HP from absorbing excitation energy.
The evolution of pore pressure fields around standard and ball penetrometers: influence of penetration rate
Authors: Elsworth Derek 
Published: August 2012

SUMMARYRate effects are examined in the steady pore pressure distribution induced as a result of penetration of standard and ball penetrometers. The incompressible flow field, which develops around the penetrometer is used to define the approximate soil velocity field local to the penetrometer tip. This prescribes the Lagrangian framework for the migration of the fluid saturated porous medium, defining the advection of induced pore pressures relative to the pressure‐monitoring locations present on the probe face. In two separate approaches, different source functions are used to define the undrained pore fluid pressures developed either (i) on the face of the penetrometer or (ii) in the material comprising the failure zone surrounding the penetrometer tip. In the first, the sources applied at the tip face balance the volume of fluid mobilized by the piston displacement of the advancing penetrometer. Alternately, a fluid source distribution is evaluated from plasticity solutions and distributed throughout the tip process zone: for a standard penetrometer, the solution is for the expansion of a spherical cavity, and for the ball penetrometer, the solution is an elastic distribution of stresses conditioned by the limit load embedded within an infinite medium. For the standard penetrometer, the transition from drained to undrained behavior occurs over about two orders of magnitude in penetration rate for pore pressures recorded at the tip (U1) and about two‐and‐a‐half orders of magnitude for the shoulder (U2). This response is strongly influenced by the rigidity of the soil and slightly influenced by the model linking induced total stresses to pore pressures. For the ball penetrometer, the transition from drained to undrained behavior also transits two‐and‐a‐half orders of magnitude in penetration rate, although it is offset to higher dimensionless penetration rates than for standard penetration. Copyright © 2012 John Wiley & Sons, Ltd.
Abiraterone acetate: a new oral treatment for prostate cancer
Authors: Chaplin Steve , Clarke Noel 
Published: August 2012

AbstractAbiraterone acetate (Zytiga) is a new treatment for metastatic castration‐resistant prostate cancer. In our New products review, Steve Chaplin presents the clinical data relating to its efficacy and adverse events and Professor Noel Clarke discusses its place in therapy.
Spin relaxation in nanowires by hyperfine coupling
Authors: Echeverría‐Arrondo C. , Sherman E. Ya. 
Published: August 2012

AbstractHyperfine interactions establish limits on spin dynamics and relaxation rates in ensembles of semiconductor quantum dots. It is the confinement of electrons which determines nonzero hyperfine coupling and leads to the spin relaxation. As a result, in nanowires one would expect the vanishing of this effect due to extended electron states. However, even for relatively clean wires, disorder plays a crucial role and makes electron localization sufficient to cause spin relaxation on the time scale of the order of 10 ns. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrospray ionization tandem mass spectrometry of chaetoglobosins
Authors: Xu Guo‐Bo , Li Li‐Mei , Fang Dong‐Mei , Li Guo‐You , Zhang Guo‐Lin , Wu Zhi‐Jun 
Published: August 2012

RATIONALEChaetoglobosins are a family of macrocyclic polyketide alkaloids. They possess many similar isomers and exhibit a wide range of biological activities. Thus, there is a need for reliable, fast, and low‐cost analysis of this class of compounds.METHODSA series of seven chaetoglobosins from Chaetomium globosum, including two types of isomers, were investigated using electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry (ESI‐QTOF‐MS/MS) in both positive‐ and negative‐ion mode. The identity of major product ions was supported by deuterium‐labeling experiments.RESULTSIn positive‐ion mode, the product ion at m/z 130 is the characteristic ion of the indolyl group. A McLafferty rearrangement might play a significant role in the fragmentation of the macrocycle moiety for most chaetoglobosins and produces two series of characteristic product ions, accompanied by neutral losses. The characteristic product ion at m/z 309 in the MS/MS spectrum of chaetoglobosins E indicates the structure of the cyclic olefinic bond in ring B and can be used to distinguish it from the isomers, chaetoglobosins Fex, which has an exocyclic double bond on ring B. In negative‐ion mode, the McLafferty rearrangement has an important role in the fragmentation pattern of the macrocycle. Some high‐abundance radical ions were detected. The radical product ion at m/z 138 might differentiate chaetoglobosins F and penochalasin F, isomers which have very similar structures.CONCLUSIONSIn summary, complementary information obtained from fragmentation experiments of [M+H]+ and [M–H]– precursor ions is especially valuable for rapid identification of chaetoglobosins. The high‐abundance radical ions in negative‐ion mode are also of scientific interest. Copyright © 2012 John Wiley & Sons, Ltd.
Evaluation of a liquid chromatography method for compound‐specific δ13C analysis of plant carbohydrates in alkaline media
Authors: Rinne Katja T. , Saurer Matthias , Streit Kathrin , Siegwolf Rolf T. W. 
Published: August 2012

RATIONALEIsotope analysis of carbohydrates is important for improved understanding of plant carbon metabolism and plant physiological response to the environment. High‐performance liquid chromatography/isotope ratio mass spectrometry (HPLC/IRMS) for direct compound‐specific δ13C measurements of soluble carbohydrates has recently been developed, but the still challenging sample preparation and the fact that no single method is capable of separating all compounds of interest hinder its wide‐spread application. Here we tested in detail a chromatography method in alkaline media.METHODSWe examined the most suitable chromatographic conditions for HPLC/IRMS analysis of carbohydrates in aqueous conifer needle extracts using a CarboPac PA20 anion‐exchange column with NaOH eluent, paying specific attention to compound yields, carbon isotope fractionation processes and the reproducibility of the method. Furthermore, we adapted and calibrated sample preparation methods for HPLC/IRMS analysis. OnGuard II cartridges were used for sample purification.RESULTSGood peak separation and highly linear and reproducible concentration and δ13C measurements were obtained. The alkaline eluent was observed to induce isomerization of hexoses, detected as reduced yields and 13 C fractionation of the affected compounds. A reproducible pre‐purification method providing ~100% yield for the carbohydrate compounds of interest was calibrated.CONCLUSIONSThe good level of peak separation obtained in this study is reflected in the good precision and linearity of concentration and δ13C results. The data provided crucial information on the behaviour of sugars in LC analysis with alkaline media. The observations highlight the importance for the application of compound‐matched standard solution for the detection and correction of instrumental biases in concentration and δ13C analysis performed under identical chromatographic conditions. The calibrated pre‐purification method is well suited for studies with complex matrices that disable the use of a spiked internal standard for the detection of procedural losses. Copyright © 2012 John Wiley & Sons, Ltd.
Trajectory calculations of space‐charge‐induced mass shifts in a linear quadrupole ion trap
Authors: Douglas D. J. , Konenkov N. V. 
Published: August 2012

RATIONALEIf too many ions are stored in a linear quadrupole ion trap, space charge causes the oscillation frequencies to decrease. Ions therefore appear at higher apparent mass‐to‐charge ratios in a mass spectrum. To further understand this process, we have used trajectory calculations of ions to determine mass shifts.METHODSTwo models of the ion cloud are used. The first assumes that the acceptance of the quadrupole is uniformly filled with ions. The second assumes that the ions have a thermal distribution trapped in the effective potential. Both give analytical descriptions of the field from space charge. Ion trajectories are calculated with and without space charge. Oscillation frequencies are determined with a Fourier transform. Shifts in oscillation frequency with space charge are then used to calculate mass shifts.RESULTSBoth ion cloud models give similar results. More diffuse ion clouds or ion clouds that have higher temperatures produce lower electric fields near the center of the trap and hence lower mass shifts. Space charge produces a nonlinear field. As a result, the discrete resonant frequencies of ions in a pure quadrupole field become distributions of frequencies. Comparisons with experiments show agreement for reasonable values of the parameters of the two ion cloud models.CONCLUSIONSThis relatively simple method for calculating the effects of space charge shows (i) that the spread of oscillation frequencies reduces mass resolution with axial ejection and (ii) that mass shifts are reduced with ion clouds with greater spatial extents or higher ion temperatures. Copyright © 2012 John Wiley & Sons, Ltd.
Arrow of time: Metaphorical construals of entropy and the second law of thermodynamics
Authors: Amin Tamer G. , Jeppsson Fredrik , Haglund Jesper , Strömdahl Helge 
Published: August 2012

AbstractVarious features of scientific discourse have been characterized in the science education literature, and challenges students face in appropriating these features have been explored. Using the framework of conceptual metaphor, this paper sought to identify explicit and implicit metaphors in pedagogical texts dealing with the concept of entropy and the second law of thermodynamics, an abstract and challenging domain for learners. Three university‐level textbooks were analyzed from a conceptual metaphor perspective, and a range of explicit and implicit metaphors were identified. Explicit metaphors identified include entropy as disorder, thermodynamics processes as movements along a path, and energetic exchange as financial transactions among others. Implicit metaphors include application and elaboration of the generic Location Event Structure metaphor, application of the Object Event Structure metaphor, and others. The similarities and differences between explicit and implicit metaphors found in the textbooks are also described. Two key pedagogical implications are discussed: that the selection of explicit instructional metaphors can be guided by consistency with implicit metaphors; and that the range of implicit metaphors found in pedagogical texts implies that a multiple instructional metaphor strategy is warranted. The depth of the phenomenon of conceptual metaphor and its implications for future research are also discussed. © 2012 Wiley Periodicals, Inc. Sci Ed 96:818–848, 2012
Proposing a core set of instructional practices and tools for teachers of science
Authors: Windschitl Mark , Thompson Jessica , Braaten Melissa , Stroupe David 
Published: August 2012

AbstractRecent calls for teacher preparation to become more grounded in practice prompt the questions: Which practices? and perhaps more fundamentally, what counts as a model of instruction worth learning for a new professional—i.e., the beginner's repertoire? In this report, we argue the following: If a defined set of subject‐specific high‐leverage practices could be articulated and taught during teacher preparation and induction, the broader teacher education community could collectively refine these practices as well as the tools and other resources that support their appropriation by novices across various learning‐to‐teach contexts. To anchor our conversation about these issues, we describe the evolution, in design, and enactment, of a “candidate core” and a suite of tools that supported the approximation of equitable and rigorous pedagogy for several groups of beginning science teachers. Their struggles and successes in taking up ambitious practice informed not only our designs for a beginner's repertoire but also a system of tools and socioprofessional routines that could foster such teaching over time. © 2012 Wiley Periodicals, Inc. Sci Ed 96:878–903, 2012
Selection of Desulfurizing Agents and Optimization of Operational Variables in Hot Metal Desulfurization
Authors: Silva Sidiney Nascimento , Vernilli Fernando , Justus Sergio Murilo , Araújo Cláudio Márcio dos Santos , Longo Elson , Varela José Arana , Lopes José Milton Gabriel , Vidal de Almeida Bruno 
Published: August 2012

AbstractThe growing demand for steels with tighter compositional specifications led the Companhia Siderúrgica Nacional (CSN) to develop more efficient processes. To solve this problem this paper aims to identify the operational variables more impacting in the desulfurization process, specifically in torpedo car, as well as its causes and solutions. Then select and test, with laboratorial and industrial tests, desulfurizing agents based of CaC2, CaO, CaCO3, and Mg to assess the cost per quantity of product desulfurized. The mixture with best results was not that one with highest content of CaC2. It is believed that this mixture showed better efficiency because of the increased agitation of the bath, produced by the releasing of gas from compound CaCO3 present in this mixture.
Labeling of neuronal receptors and transporters with quantum dots
Authors: Chang Jerry C. , Kovtun Oleg , Blakely Randy D. , Rosenthal Sandra J. 
Published: August 2012

AbstractThe ability to efficiently visualize protein targets in cells is a fundamental goal in biological research. Recently, quantum dots (QDots) have emerged as a powerful class of fluorescent probes for labeling membrane proteins in living cells because of breakthrough advances in QDot surface chemistry and biofunctionalization strategies. This review discusses the increasing use of QDots for fluorescence imaging of neuronal receptors and transporters. The readers are briefly introduced to QDot structure, photophysical properties, and common synthetic routes toward the generation of water‐soluble QDots. The following section highlights several reports of QDot application that seek to unravel molecular aspects of neuronal receptor and transporter regulation and trafficking. This article is closed with a prospectus of the future of derivatized QDots in neurobiological and pharmacological research. WIREs Nanomed Nanobiotechnol 2012, 4:605–619. doi: 10.1002/wnan.1186This article is categorized under:

Diagnostic Tools > In Vitro Nanoparticle-Based Sensing
Diagnostic Tools > In Vivo Nanodiagnostics and Imaging
A novel concept of identifying precancerous cells to enhance anti‐cancer therapies
Authors: Zheng Yun‐Wen , Tsuchida Tomonori , Taniguchi Hideki 
Published: August 2012

AbstractCancer is the leading cause of death worldwide and mortality due to cancer continues to rise. Cancer cell resistance to chemoradiotherapy is hindering treatment efforts in clinics. Prevention strategies and early detection thus may reduce mortality. In this study, we have proposed the concept of using precancerous cells and their progeny in cancer therapy, which could provide unique insights for early cancer diagnosis, treatment, and preventive therapy. In addition to discussing the nature and characteristics of precancerous cells and their progeny, we have also introduced an effective precancerous cell‐targeted therapy based on an animal model of hepatocellular carcinoma. Anti‐precancerous cell drug development should be a major target during cancer elimination and it may lead to preventive therapies for individuals with a high risk of developing cancer.
The impact of habitat fragmentation on the interaction betweenCentaurium erythraea(Gentianaceae) and its specialized seed predatorStenoptilia zophodactylus(Pterophoridae, Lepidoptera)
Authors: De Crop Eske , Brys Rein , Hoffmann Maurice 
Published: August 2012

AbstractHabitat fragmentation can affect plant population characteristics and plant traits, which in turn can change biotic interactions, such as plant–insect interactions. Because of this, habitat fragmentation can affect reproductive success and survival of both the plant and seed predators, especially when the predator is rare and specialized. This study focuses on the level of fruit predation inCentaurium erythraeaby its specific seed predator, the plume mothStenoptilia zophodactylus, in a fragmented coastal dune landscape. To investigate the consequences of habitat fragmentation, we assessed the effect of population and plant characteristics of 25C. erythraeapopulations on fruit predation byS. zophodactylus. Although the distribution of this specialized predator is poorly documented, our results show thatS. zophodactylusoccurred frequently in most of the studiedC. erythraeapopulations. We found a strong correlation between the spatial isolation of the host plant and the level of fruit predation, with low predation in isolated populations, most likely due to the limited dispersion capacity of the plume moth.C. erythraeaindividuals experienced a higher risk of fruit predation when showing a large floral display size, presumably because they are more attractive. However, at fruit level, the risk of predation decreases with increasing floral display at individual plant level, representing a sort of dilution effect. Our findings indicate that maintaining and restoring large, dense and rather connected populations ofC. erythraeawill be beneficial for the sustainable conservation of the rare specialist seed predatorS. zophodactylus, without increasing the predation pressure on the host plant.
Time is on our side: the importance of considering a recovery period when assessing flooding tolerance in plants
Authors: Striker Gustavo Gabriel 
Published: August 2012

AbstractThere is wide consensus about the significance of monitoring plant responses during flooding when evaluating specific tolerance. Nonetheless, plant recovery once water recedes has often been overlooked. This note highlights the importance of registering plant performance during a recovery phase. Two opposite types of plant growth responses, during and after flooding, are discussed. It is shown that an apparently poor performance during flooding does not necessarily involve a reduced tolerance, as plants can prioritize saving energy and carbohydrates for later resumption of vigorous growth during recovery. Conversely, maintenance of positive plant growth during flooding can imply extensive depletion of reserves, consequently constraining future plant growth. Therefore, to accurately estimate real tolerance to this stress, plant performance should be appraised during both flooding and recovery periods.