bluuebunny/crossref_metadata_2025 huggingface dataset:
The mechanics of rigid irregular particles subject to uniaxial compression
Authors: CAVARRETTA I. , O'SULLIVAN C.
Published: June 2012

Single-particle compression tests, in which an individual sand grain is vertically compressed between two rigid horizontal platens, are often used in particle-scale soil mechanics studies. They are useful index tests to examine the susceptibility of a given sand to particle breakage; they provide information for calibration of particulate discrete-element models that capture crushing; and they can give information on size–strength relationships. The test is conceptually simple, but the response of an irregular particle in these compression tests is not straightforward. During compression the particle can rotate. Both horizontal and vertical forces are induced at the particle–platen contacts, and so there may be frictional sliding at the contact points at the same time as, or prior to, compression of the bulk particle. Asperities can yield, changing the particle geometry. The variation in the response mechanism during compression leads to a load–deformation response that is not always easy to interpret. This paper describes two relatively simple analytical studies of an irregular particle in a particle compression test. The susceptibility of the particle to rotation under the applied compressive force is shown to depend on the particle geometry and the particle–platen friction. The rotation of the particle is shown to induce a kinematic degradation or reduction in the effective stiffness of the system, and the system stiffness depends on the particle size. Frictional sliding at the contact points will also cause a reduction in stiffness. These observations may have implications not only for the test itself, but also for the response of irregular particles participating in the strong force chains in stressed granular materials.
Numerical simulations of pipe–soil interaction during large lateral movements on clay
Authors: CHATTERJEE S. , WHITE D.J. , RANDOLPH M.F.
Published: June 2012

The soil resistance during large lateral movements of pipelines across the seabed is an important input to design solutions for the management of thermal and pressure-induced expansions. To investigate this behaviour, a large-deformation finite-element (LDFE) analysis method involving frequent remeshing was employed. The LDFE method allows the changing geometry of the seabed when disturbed by the pipeline to be incorporated. Also, the effects of strain rate and strain-softening on the undrained shear strength of the soil were accounted for. A back-analysis of a centrifuge modelling simulation was first performed, for validation, and then a parametric study varying the pipe weight and initial embedment was undertaken. The results show that a steady state is generally reached at large displacements, reflecting a balance between the growth of a soil berm ahead of the pipe and the softening of the disturbed soil. The initial breakout response matched well with previously established failure envelopes, and a new interpretation has been proposed to capture the large-displacement response. The ‘effective embedment' concept is used to rationalise the influence of the soil berm ahead of the pipe. This leads to simple new relationships for predicting the steady-state residual lateral resistance, which provide more accurate predictions of the LDFE response than previously established solutions. The complete load–displacement response over large movements was also shown to be well fitted by an exponential relationship, albeit for the specific case of lateral movements under constant vertical load.
Modelling the effect of initial density on soil-water characteristic curves
Authors: ZHOU A.-N. , SHENG D. , CARTER J.P.
Published: June 2012

This paper presents a simple approach to quantify the effect of initial soil density on the soil-water characteristic curve (SWCC) of unsaturated soils. This approach is based on an incremental relationship between the degree of saturation and the initial void ratio, which satisfies the intrinsic constraints for three-phase porous materials. The incremental relationship can be incorporated into existing SWCC equations to model the water retention behaviour for deformable soils. Only one additional parameter is introduced, which can be conveniently calibrated by way of conventional water retention tests. The SWCCs for the same soil at different initial void ratios can be found using the proposed approach. The proposed approach is validated against experimental data from drying tests for both compacted and reconstituted soils.
Extended stress field analysis of surface strip footing on sand
Authors: SPASOJEVIC A. , CABARKAPA Z.
Published: June 2012

Maksimovic's non-linear failure envelope and the consistent model of footing roughness provide the backdrop to the development of a comprehensive extension of the stress field method, which is applied to the analysis of surface footings on sand in plane strain. The note derives governing non-dimensional equations and discusses issues pertinent to the extended stress field method: modelling of the shear strength in the ultra-low stress range; internal lengths that produce scale-dependent bearing capacity factors; and the relation between slip-lines and characteristics. For constant friction angles the note produces scale-independent solutions that perfectly match already published results. For friction angles degrading with pressure, the note numerically quantifies and theoretically explains the scale dependence of the bearing capacity factor Nγ. The note shows why friction models with finite shear strength at ultra-low stresses produce Nγs ranging from Nγ(φB + ∆φ) for very small to Nγ(φB) for very large surface footings, and identifies the internal length parameter, γB/pN, as the controlling factor. Theoretical bearing capacity factors are shown to match well with experimentally obtained factors.
Adjunctive Treatment of Chronic Periodontitis With Systemic Low‐Dose Aspirin Therapy
Authors: Geisinger Maria L. , Holmes Carolyn M. , Vassilopoulos Philip J. , Geurs Nicolaas C. , Reddy Michael S.
Published: June 2012

Focused Clinical Question

In patients presenting with generalized moderate‐to‐severe chronic periodontitis (CP), does adjunctive use of systemic low‐dose aspirin therapy with non‐surgical periodontal therapy improve the maintenance of alveolar bone support and/or clinical attachment level?

Clinical Scenario

A 55‐year‐old male presents for a periodontal evaluation after deep pockets were noted at a periodontal maintenance visit. The patient reports a dental history significant for non‐surgical periodontal therapy and resective osseous surgery ≈18 years before the current evaluation, and has been seeing a general dentist for periodontal maintenance every 6 months since his surgical treatment. The patient also reports a medical history significant for hypertension and a recent transient ischemic attack (TIA). After the TIA, the patient was placed on 325 mg acetylsalicylic acid daily to reduce his risk of cardiovascular and cerebrovascular events. The treatment plan includes non‐surgical periodontal therapy followed by resective and regenerative surgeries. During medical consultation, the patient's physician states a preference that the patient continue taking aspirin therapy throughout periodontal treatment. The patient is concerned about disease progression after the previous surgical therapy and inquires about the advantages and disadvantages of low‐dose aspirin therapy use in patients with CP. See Figures 1 through 3 for the intraoral presentation of the patient.
Updated criteria for diagnosis and risk stratification in patients with multiple myeloma
Authors: Djurdjevic Predrag , Andjelkovic Nebojsa , Bila Jelena
Published: June 2012

Search and disclosure of most adequate diagnostic criteria and prognostic
indicators of disease represents one of the most difficult tasks in the
understanding of any disease, which creates the way toward a more successful
treatment and longer survival. The recent advances in research techniques
that have helped refine the diagnostic work up and prognosis of myeloma
include serum-free light chains, especially in oligosecretory myeloma,
magnetic resonance and positron emission tomography in the diagnosis of bone
diseases, cytogenetics and fluorescent in situ hibridization (FISH) technique
to determine prognosis. The International Staging System and Durie/Salmon
PLUS system are the current standards for staging myeloma. Newer risk
stratification protocols are based on international staging system and
chromosomal changes detected by conventional cytogenetics and FISH. These
improved predictive risk stratification models have enabled the determination
of prognosis in patients with myeloma which has a considerable influence on
the choice of therapeutic algorism. Novel therapies enable a significant
increase in achieving complete remission in a significant number of patients
which also results in the definition of more precise criteria regarding the
response to therapy. A firm and complete remission with a very good partial
remission represent new categories defined by the international uniform
criteria of response to therapy. This paper provides the current criteria for
diagnosis, staging, risk stratification and response assessment of myeloma.
Clinical efficacy of novel therapeutic combinations in the treatment of patients with relapsed or refractory myeloma
Authors: Savic Ivanka , Popovic Stevan
Published: June 2012

Despite all advances in the treatment of patients with multiple myeloma,
relapse is a constant event in this disease. Novel therapeutic agents like
proteasome inhibitors, immunomodulatory drugs and their combinations have
improved overall survival in patients with relapsed or refractory myeloma,
with partial remission achieved in 50-70% and median duration of 6-14 months,
as well as the quality of life of these patients. The novel therapeutic
agents presented known and acceptable safety profile. The choice of the
appropriate regimen is depending on components of initial therapy, degree of
response and remission duration, patient?s status like age, performance
status, renal function impairment, pre-existing medical toxicity, cytogenetic
abnormalities and, at the other side, aggressiveness of relapsed disease.
A Longitudinal Study of Listening Perception in Adult Learners of English: Implications for Teachers
Authors: Derwing Tracey M. , Thomson Ron I. , Foote Jennifer A. , Munro Murray J.
Published: June 2012

Abstract:

This study is intended to help ESL (English as a second language) instructors make evidence-based decisions based on second language (L2) listening-development findings when selecting features for pronunciation instruction. In a longitudinal study of listening perception, we examined five common problems to determine which were most likely to improve in the absence of explicit instruction and which ones did not improve over time. Twenty Mandarin and 20 Slavic language speakers completed 5 tasks at 2-month intervals over a period of 10 months; we measured their listening perception of word stress, sentence stress, intonation, can/can’t, and -teen/-ty number distinctions. We also compared the participants’ scores at the final testing time to native speaker scores on the same tests. The L2 learners’ perceptions of sentence stress, intonation, and -teen/-ty number distinctions improved while their perceptions of word stress and can/can’t did not. When the L2 speakers’ performance on the tests at the 10-month point was compared to that of the native speakers, there were no significant differences for word stress, intonation, and -teen/-ty number distinctions. However, the native speakers significantly outperformed the Slavic speakers on sentence stress and outperformed both the Slavic and Mandarin speakers on can/can’t distinctions. Implications for pronunciation teaching within general adult ESL classes are discussed.
Chronique commentée des décisions de l'Organe de Règlement des Différends (juin 2010-novembre 2011)
Authors: Busseuil Guillaume , Garinot Jean-Marie , Grayot-Dirx Stéphanie , Jourdain-Fortier Clotilde , Moine-Dupuis Isabelle
Published: June 2012

Cette année de décisions de l’Organe de Règlement des Différends (ORD) nous permet, à la suite des précédentes, d’observer, et aussi de tenter d’évaluer, les rapports entre la libéralisation du commerce international et les valeurs non marchandes. Valeurs non marchandes ou intérêts économiques ? Les plaignants qui mettent en avant ces valeurs (santé publique, environnement...) sont fréquemment suspectés – parfois à juste titre – de ne les utiliser que comme prétexte à des attitudes protectionnistes (voir notamment affaires Chine – Matières premières, États-Unis – Cigarettes aux clous de girofle ). Réussir à convaincre est d’une importance primordiale, d’où une importance croissante des questions procédurales, ou liées à l’office du juge de l’ORD, qui tiennent une part non négligeable dans la présente chronique. Plusieurs Accords étaient invoqués par les plaignants : le GATT de 1994, le plus fréquemment, mais aussi l’Accord OTC, l’Accord SMC. Enfin, nous noterons la longueur de certains litiges (l’affaire Pommes  – commencée en 2007, qui semble avoir trouvé son épilogue – ou l’affaire Aéronefs gros porteurs  – la plainte contre Airbus datant de 2004).
Breakdown in Repression of IFN-γ mRNA Leads to Accumulation of Self-Reactive Effector CD8+ T Cells
Authors: Chang Pheh-Ping , Lee Sau K. , Hu Xin , Davey Gayle , Duan Guowen , Cho Jae-Ho , Karupiah Guna , Sprent Jonathan , Heath William R. , Bertram Edward M. , Vinuesa Carola G.
Published: June 2012

Tight regulation of virus-induced cytotoxic effector CD8+ T cells is essential to prevent immunopathology. Naturally occurring effector CD8+ T cells, with a KLRG1hi CD62Llo phenotype typical of short-lived effector CD8+ T cells (SLECs), can be found in increased numbers in autoimmune-prone mice, most notably in mice homozygous for the san allele of Roquin. These SLEC-like cells were able to trigger autoimmune diabetes in a susceptible background. When Roquin is mutated (Roquinsan), effector CD8+ T cells accumulate in a cell-autonomous manner, most prominently as SLEC-like effectors. Excessive IFN-γ promotes the accumulation of SLEC-like cells, increases their T-bet expression, and enhances their granzyme B production in vivo. We show that overexpression of IFN-γ was caused by failed posttranscriptional repression of Ifng mRNA. This study identifies a novel mechanism that prevents accumulation of self-reactive cytotoxic effectors, highlighting the importance of regulating Ifng mRNA stability to maintain CD8+ T cell homeostasis and prevent CD8-mediated autoimmunity.
A Role for the NF-κB Pathway in Cell Protection from Complement-Dependent Cytotoxicity
Authors: Gancz Dana , Lusthaus Michal , Fishelson Zvi
Published: June 2012

Nucleated cells are equipped with several mechanisms that support their resistance to complement-dependent cytotoxicity (CDC). The role of the NF-κB pathway in cell protection from CDC was examined. Elevated sensitivity to CDC was demonstrated in cells lacking the p65 subunit of NF-κB or the IκB kinases IKKα or IKKβ, and in cells treated with p65 small interfering RNA. Pretreatment with the IKK inhibitor PS-1145 also enhanced CDC of wild-type cells (WT) but not of p65−/− cells. Furthermore, reconstitution of p65 into p65−/− cells and overexpression of p65 in WT cells lowered their sensitivity to CDC. The postulated effect of p65 on the JNK-mediated death-signaling pathway activated by complement was examined. p65 small interfering RNA enhanced CDC in WT cells but not in cells lacking JNK. JNK phosphorylation induced by complement was more pronounced in p65−/− cells than in WT cells. The results indicate that the NF-κB pathway mediates cell resistance to CDC, possibly by suppressing JNK-dependent programmed necrotic cell death.
Activation of Invariant NKT Cells in Early Phase of Experimental Autoimmune Encephalomyelitis Results in Differentiation of Ly6Chi Inflammatory Monocyte to M2 Macrophages and Improved Outcome
Authors: Denney Laura , Kok Wai Ling , Cole Suzanne L. , Sanderson Sharon , McMichael Andrew J. , Ho Ling-Pei
Published: June 2012

Neuropathology in multiple sclerosis is closely linked to presence of macrophages in the CNS. Both M1 (inflammatory) and M2 (alternatively activated, noninflammatory) macrophages are found in the inflamed CNS and thought to differentiate from infiltrating monocytes. It is unclear whether the balance of M1 and M2 macrophages can be altered and whether this affects disease outcome. We show in this article that Ly6Chi inflammatory monocytes are the early and dominant infiltrating cells in the CNS during experimental autoimmune encephalomyelitis, a model for the acute phase of multiple sclerosis. Activation of invariant NKT (iNKT) cells reduced the frequency of Ly6Chi monocytes and increased the proportion of M2 macrophages in the CNS with associated improvement in neurologic impairment. In contrast, iNKT-deficient mice showed higher numbers of Ly6Chi monocytes, reduced M2, and much more severe disease. Adoptive transfer of M2-enriched cells to iNKT-deficient mice markedly improved neurologic impairment. In vitro and in vivo experiments showed that iNKT cells promote differentiation of monocytes to M2 macrophages in an IL-4 and CD1d-dependent process. These findings indicate that infiltrating Ly6Chi inflammatory monocytes are early players in acute neuroinflammation and that their frequency and differentiation can be influenced by activation of iNKT cells with resultant improvement in disease outcome.
Ablation of Leptin Receptor-Mediated ERK Activation Impairs Host Defense against Gram-Negative Pneumonia
Authors: Mancuso Peter , Myers Martin G. , Goel Deepti , Serezani Carlos H. , O’Brien Edmund , Goldberg Jared , Aronoff David M. , Peters-Golden Marc
Published: June 2012

The adipocyte-derived hormone leptin plays an important role in regulation of energy homeostasis and the innate immune response against bacterial infections. Leptin’s actions are mediated by signaling events initiated by phosphorylation of tyrosine residues on the long form of the leptin receptor. We recently reported that disruption of leptin receptor-mediated STAT3 activation augmented host defense against pneumococcal pneumonia. In this report, we assessed leptin receptor-mediated ERK activation, a pathway that was ablated in the l/l mouse through a mutation of the tyrosine 985 residue in the leptin receptor, to determine its role in host defense against bacterial pneumonia in vivo and in alveolar macrophage (AM) antibacterial functions in vitro. l/l mice exhibited increased mortality and impaired pulmonary bacterial clearance after intratracheal challenge with Klebsiella pneumoniae. The synthesis of cysteinyl-leukotrienes was reduced and that of PGE2 enhanced in AMs in vitro and the lungs of l/l mice after infection with K. pneumoniae in vivo. We also observed reduced phagocytosis and killing of K. pneumoniae in AMs from l/l mice that was associated with reduced reactive oxygen intermediate production in vitro. cAMP, known to suppress phagocytosis, bactericidal capacity, and reactive oxygen intermediate production, was also increased 2-fold in AMs from l/l mice. Pharmacologic blockade of PGE2 synthesis reduced cAMP levels and overcame the defective phagocytosis and killing of bacteria in AMs from l/l mice in vitro. These results demonstrate that leptin receptor-mediated ERK activation plays an essential role in host defense against bacterial pneumonia and in leukocyte antibacterial effector functions.
Fetal-Specific CD8+ Cytotoxic T Cell Responses Develop during Normal Human Pregnancy and Exhibit Broad Functional Capacity
Authors: Lissauer David , Piper Karen , Goodyear Oliver , Kilby Mark D. , Moss Paul A. H.
Published: June 2012

Tolerance of the semiallogeneic fetus presents a significant challenge to the maternal immune system during human pregnancy. T cells with specificity for fetal epitopes have been detected in women with a history of previous pregnancy, but it has been thought that such fetal-specific cells were generally deleted during pregnancy as a mechanism to maintain maternal tolerance of the fetus. We used MHC-peptide dextramer multimers containing an immunodominant peptide derived from HY to identify fetal-specific T cells in women who were pregnant with a male fetus. Fetal-specific CD8+ T lymphocytes were observed in half of all pregnancies and often became detectable from the first trimester. The fetal-specific immune response increased during pregnancy and persisted in the postnatal period. Fetal-specific cells demonstrated an effector memory phenotype and were broadly functional. They retained their ability to proliferate, secrete IFN-γ, and lyse target cells following recognition of naturally processed peptide on male cells. These data show that the development of a fetal-specific adaptive cellular immune response is a normal consequence of human pregnancy and that unlike reports from some murine models, fetal-specific T cells are not deleted during human pregnancy. This has broad implications for study of the natural physiology of pregnancy and for the understanding of pregnancy-related complications.
Radiotherapy Promotes Tumor-Specific Effector CD8+ T Cells via Dendritic Cell Activation
Authors: Gupta Anurag , Probst Hans Christian , Vuong Van , Landshammer Alexandro , Muth Sabine , Yagita Hideo , Schwendener Reto , Pruschy Martin , Knuth Alexander , van den Broek Maries
Published: June 2012

Radiotherapy is an important treatment for cancer. The main mode of action is thought to be the irreversible damage to tumor cell DNA, but there is evidence that irradiation mobilizes tumor-specific immunity, and recent studies showed that the efficacy of high-dose radiotherapy depends on the presence of CD8+ T cells. We show in this study that the efficacy of radiotherapy given as a single, high dose (10 Gy) crucially depends on dendritic cells and CD8+ T cells, whereas CD4+ T cells or macrophages are dispensable. We show that local high-dose irradiation results in activation of tumor-associated dendritic cells that in turn support tumor-specific effector CD8+ T cells, thus identifying the mechanism that underlies radiotherapy-induced mobilization of tumor-specific immunity. We propose that in the absence of irradiation, the activation status of dendritic cells rather than the amount of tumor-derived Ag is the bottleneck, which precludes efficient anti-tumor immunity.
Twist1 Regulates Ifng Expression in Th1 Cells by Interfering with Runx3 Function
Authors: Pham Duy , Vincentz Joshua W. , Firulli Anthony B. , Kaplan Mark H.
Published: June 2012

A transcription factor network that includes STAT4, T-bet, and Runx3 promotes the differentiation of Th1 cells and inflammatory immune responses. How additional transcription factors regulate the function of Th1 cells has not been defined. In this study we show that the negative regulatory factor Twist1 decreases expression of T-bet, Runx3, and IL-12Rβ2 as it inhibits IFN-γ production. Ectopic expression of Runx3, but not T-bet or IL-12Rβ2, compensates for the effects of Twist1 on IFN-γ production, and Twist1 regulation of Ifng depends on complex formation with Runx3. Twist1 decreases Runx3 and T-bet binding at the Ifng locus, and it decreases chromatin looping within the Ifng locus. These data define an IL-12/STAT4–induced negative regulatory loop that impacts multiple components of the Th1 transcriptional network and provide further insight into regulation of Th1 differentiation.
Chamber simulation of photooxidation of dimethyl sulfide and isoprene in the presence of NOx
Authors: Chen T. , Jang M.
Published: June 2012

Abstract. In the kinetic model of this study, to advance the photooxidation of dimethyl sulfide (DMS) in the gas phase, the most recently reported reactions with their rate constants have been included. To improve the model predictability for the formation of sulfuric acid and methanesulfonic acid (MSA), heterogeneous reactions of gaseous DMS products (e.g., dimethyl sulfoxide (DMSO)) on the surface of aerosol have been included in the kinetic model. DMS was photoirradiated in the presence of NOx using a 2 m3 Teflon film chamber. The resulting chamber data was simulated using the new kinetic model. The model included in this study predicted that concentrations of both MSA and H2SO4 would significantly increase due to heterogeneous chemistry and this was well substantiated with experimental data. The model used in this study also predicted the decay of DMS, the formation of other gaseous products such as SO2, dimethyl sulfone (DMSO2), and the ozone formation linked to a NOx cycle. To study the effect of coexisting volatile organic compounds, the photooxidation of DMS in the presence of isoprene and NOx has been simulated using the new kinetic model integrated with the Master Chemical Mechanism (MCM) for isoprene oxidation, and compared to chamber data. Both the model simulation and the experimental data showed an increase in the yields of MSA and H2SO4 as the isoprene concentration increased.
Organic matter sources, fluxes and greenhouse gas exchange in the Oubangui River (Congo River basin)
Authors: Bouillon S. , Yambélé A. , Spencer R. G. M. , Gillikin D. P. , Hernes P. J. , Six J. , Merckx R. , Borges A. V.
Published: June 2012

Abstract. The Oubangui is a major tributary of the Congo River, draining an area of ~500 000 km2 mainly consisting of wooded savannahs. Here, we report results of a one year long, 2-weekly sampling campaign in Bangui (Central African Republic) since March 2010 for a suite of physico-chemical and biogeochemical characteristics, including total suspended matter (TSM), bulk concentration and stable isotope composition of particulate organic carbon (POC and δ13CPOC), particulate nitrogen (PN and δ15NPN), dissolved organic carbon (DOC and δ13CDOC), dissolved inorganic carbon (DIC and δ13CDIC), dissolved greenhouse gases (CO2, CH4 and N2O), and dissolved lignin composition. δ13C signatures of both POC and DOC showed strong seasonal variations (−30.6 to −25.8‰, and −31.8 to −27.1‰, respectively), but their different timing indicates that the origins of POC and DOC may vary strongly over the hydrograph and are largely uncoupled, differing up to 6‰ in δ13C signatures. Dissolved lignin characteristics (carbon-normalised yields, cinnamyl:vanillyl phenol ratios, and vanillic acid to vanillin ratios) showed marked differences between high and low discharge conditions, consistent with major seasonal variations in the sources of dissolved organic matter. We observed a strong seasonality in pCO2, ranging between 470 ± 203 ppm for Q < 1000 m3 s−1 (n=10) to a maximum of 3750 ppm during the first stage of the rising discharge. The low POC/PN ratios, high %POC and low and variable δ13CPOC signatures during low flow conditions suggest that the majority of the POC pool during this period consists of in situ produced phytoplankton, consistent with concurrent pCO2 (partial pressure of CO2) values only slightly above and, occasionally, below atmospheric equilibrium. Water-atmosphere CO2 fluxes estimated using two independent approaches averaged 105 and 204 g C m−2 yr−1, i.e. more than an order of magnitude lower than current estimates for large tropical rivers globally. Although tropical rivers are often assumed to show much higher CO2 effluxes compared to temperate systems, we show that in situ production may be high enough to dominate the particulate organic carbon pool, and lower pCO2 values to near equilibrium values during low discharge conditions. The total annual flux of TSM, POC, PN, DOC and DIC are 2.33 Tg yr−1, 0.14 Tg C yr−1, 0.014 Tg N yr−1, 0.70 Tg C yr−1, and 0.49 Tg C yr−1, respectively. While our TSM and POC fluxes are similar to previous estimates for the Oubangui, DOC fluxes were ~30% higher and bicarbonate fluxes were ~35% lower than previous reports. DIC represented 58% of the total annual C flux, and under the assumptions that carbonate weathering represents 25% of the DIC flux and that CO2 from respiration drives chemical weathering, this flux is equivalent to ~50% of terrestrial-derived riverine C transport.
An educational model for ensemble streamflow simulation and uncertainty analysis
Authors: AghaKouchak A. , Nakhjiri N. , Habib E.
Published: June 2012

Abstract. This paper presents a hands-on modeling toolbox, HBV-Ensemble, designed as a complement to theoretical hydrology lectures, to teach hydrological processes and their uncertainties. The HBV-Ensemble can be used for in-class lab practices and homework assignments, and assessment of students' understanding of hydrological processes. Using this model, students can gain more insights into how hydrological processes (e.g., precipitation, snowmelt and snow accumulation, soil moisture, evapotranspiration and runoff generation) are interconnected. The model includes a MATLAB Graphical User Interface (GUI) and an ensemble simulation scheme that can be used for not only hydrological processes, but also for teaching uncertainty analysis, parameter estimation, ensemble simulation and model sensitivity.
Simulating melt, runoff and refreezing on Nordenskiöldbreen, Svalbard, using a coupled snow and energy balance model
Authors: van Pelt W. J. J. , Oerlemans J. , Reijmer C. H. , Pohjola V. A. , Pettersson R. , van Angelen J. H.
Published: June 2012

Abstract. A distributed energy balance model is coupled to a multi-layer snow model in order to study the mass balance evolution and the impact of refreezing on the mass budget of Nordenskiöldbreen, Svalbard. The model is forced with output from the regional climate model RACMO and meteorological data from Svalbard Airport. Extensive calibration and initialisation are performed to increase the model accuracy. For the period 1989–2010, we find a mean net mass balance of −0.39 m w.e. a−1. Refreezing contributes on average 0.27 m w.e. a−1 to the mass budget and is most pronounced in the accumulation zone. The simulated mass balance, radiative fluxes and subsurface profiles are validated against observations and are generally in good agreement. Climate sensitivity experiments reveal a non-linear, seasonally dependent response of the mass balance, refreezing and runoff to changes in temperature and precipitation. It is shown that including seasonality in climate change, with less pronounced summer warming, reduces the sensitivity of the mass balance and equilibrium line altitude (ELA) estimates in a future climate. The amount of refreezing is shown to be rather insensitive to changes in climate.
Depression‐Related Behavioral Tests
Authors: Powell Timothy R. , Fernandes Cathy , Schalkwyk Leonard C.
Published: June 2012

Overlapping characteristics between human depressive phenotypes and mouse behaviors has led to the creation of mouse models that aim to investigate the pathophysiology and treatment of unipolar depression. Behavioral tests in mice are used to assess and quantify the extent to which a mouse model displays a depression‐like phenotype. The forced swim test and tail suspension test, sucrose preference test, and novelty suppressed feeding tests all aim to measure different components of depression. However, each one of these tests has different strengths and weaknesses in terms of predictive, face and construct validities. Furthermore, the responses to these tests vary greatly depending on strain of mouse. Depression‐related behavioral tests are an extremely useful investigative tool in unearthing causes and predicting treatment outcomes in human depression, but as this review demonstrates, the comprehension of the finer details are extremely important in the design, analysis, and evaluation of such mouse studies.Curr. Protoc. Mouse Biol. 2:119‐127 © 2012 by John Wiley & Sons, Inc.
Copper‐Catalyzed Aerobic Oxidative Synthesis of 5‐Substituted Imidazo/Benzimidazoquinazolinones through Intramolecular CH Amination
Authors: Chen Lujun , Li Chao , Bi Xin , Liu Hongxia , Qiao Renzhong
Published: June 2012

A simple and efficient copper‐catalyzed aerobic oxidative method for the synthesis of imidazo/benzimidazoquinazolinones has been developed through direct intramolecular CH amination of (1H‐imidazol‐1‐yl)[2‐(alkylamino)phenyl]methanones, and the corresponding target products were obtained in moderate to good yields.
Coordinated reset has sustained aftereffects in Parkinsonian monkeys
Authors: Tass Peter A. , Qin Li , Hauptmann Christian , Dovero Sandra , Bezard Erwan , Boraud Thomas , Meissner Wassilios G.
Published: June 2012

Coordinated reset neuromodulation consists of the application of consecutive brief high‐frequency pulse trains through the different contacts of the stimulation electrode. In theoretical studies, by achieving unlearning of abnormal connectivity between neurons, coordinated reset neuromodulation reduces pathological synchronization, a hallmark feature of Parkinson's disease pathophysiology. Here we show that coordinated reset neuromodulation of the subthalamic nucleus has both acute and sustained long‐lasting aftereffects on motor function in parkinsonian nonhuman primates. Long‐lasting aftereffects were not observed with classical deep brain stimulation. These observations encourage further development of coordinated reset neuromodulation for treating motor symptoms in Parkinson disease patients. ANN NEUROL 2012;72:816–820
A predictive clinical–genetic model of tissue plasminogen activator response in acute ischemic stroke
Authors: del Río‐Espínola Alberto , Fernández‐Cadenas Israel , Giralt Dolors , Quiroga Adoracion , Gutiérrez‐Agulló Maria , Quintana Manuel , Fernández‐Álvarez Patricia , Domingues‐Montanari Sophie , Mendióroz Maite , Delgado Pilar , Turck Natacha , Ruíz Agustin , Ribó Marc , Castellanos Mar , Obach Victor , Martínez Sergi , Freijo Mari Mar , Jiménez‐Conde Jordi , Cuadrado‐Godia Elisa , Roquer Jaume , Chacón Pilar , Martí‐Fábregas Joan , Sánchez Jean Charles ,   the GRECOS Investigators, Montaner Joan
Published: June 2012

Objective:

Wide interindividual variability exists in response to tissue plasminogen activator (t‐PA) treatment in the acute phase of ischemic stroke. We aimed to find genetic variations associated with hemorrhagic transformation (HT) and mortality rates after t‐PA. We then generated a clinical–genetic model for predicting t‐PA response.

Methods:

Our prospective study used SNPlex to genotype 140 single nucleotide polymorphisms (SNPs) from 97 candidate genes in 3 patient cohorts. The cohorts included 1,172 patients who were treated with t‐PA; 20.9% of them developed HT as evaluated by systematic brain computed tomography scan, and 10.6% died. A predictive model was generated by logistic regression (LR). Functional studies included real time quantitative polymerase chain reaction, nephelometry, and Western blot for alpha‐2‐macroglobulin (A2M) and activated partial thromboplastin time measurement for coagulation factor XII (FXII).

Results:

Replication analysis revealed that the SNP rs669 (Val1000Ile) in A2M was associated with HT, and rs1801020 (−4C>T) of F12 was associated with in‐hospital death. The rs669 SNP withstood Bonferroni correction for HT (p < 3.57E−4). LR‐based scores predicted HT occurrence (p = 9.13E−15) and in‐hospital mortality (p = 8.7E−9) and were validated in an independent cohort. Val1000Ile modified A2M serum levels at baseline and after t‐PA infusion, but not mRNA expression or protein structure; −4C>T affected FXII activity both prior to and after t‐PA treatment.

Interpretation:

Two functional polymorphisms were consistently associated with t‐PA safety. Our validated LR‐based score predicts t‐PA safety in the Spanish population. ANN NEUROL 2012;72:716–729
Preparation of microcellular thermoplastic elastomer foams from polystyrene‐b‐ethylene‐butylene‐b‐polystyrene (SEBS) and their blends with polystyrene
Authors: Sharudin Rahida Wati Binti , Ohshima Masahiro
Published: June 2012

A microcellular foam was prepared from a thermoplastic elastomer by a batch physical foaming with CO2. Two hydrogenated polystyrene‐b‐polybutadiene‐b‐polystyrene (SEBS) copolymers with different styrene ratios were used as an elastomer basis and blended with polystyrene (PS) to control their rigidity and gas permeability. The end‐blocks of the SEBS form a physical cross‐link and provide a rubber‐like elasticity when cooled. SEBS alone, with its lower styrene content, cannot be physically foamed while retaining a stable‐shape dimension because of its higher gas permeability and lower rigidity. SEBS with higher styrene contents were used, or the PS blend ratio was increased to 80/20 or 50/50, and batch physical foaming experiments were conducted at three temperature levels (60, 100, and 120°C) while the sorption CO2pressure was maintained at 10 MPa. Increasing the styrene content or blending PS with SEBS increased the storage modulus and decreased the gas permeability. As a result, the shrinkage of the foam was controlled, and stable microcellular elastomer foams could be prepared. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The performance of a two‐stage analysis of ABAB/BABA crossover trials
Authors: Kabaila Paul , Vicendese Matthew
Published: June 2012

Freeman has considered the following two‐stage procedure for finding a confidence interval for the treatment difference theta, using data from an AB/BA crossover trial. In the first stage, a preliminary test of the null hypothesis that the differential carryover is zero is carried out. If this hypothesis is accepted then the confidence interval for theta is constructed assuming that the differential carryover is zero. If, on the other hand, this hypothesis is rejected then this confidence interval is constructed using only data from the first period. Freeman has shown that this confidence interval has minimum coverage probability far below nominal. He therefore concludes that this confidence interval should not be used. In the present paper, we analyze the performance of a similar two‐stage procedure for an ABAB/BABA crossover trial. This trial differs in very significant ways from an AB/BA crossover trial, including the fact that for an ABAB/BABA crossover trial there is an unbiased estimator of the differential carryover that is unaffected by between‐subject variation. Despite these great differences, we arrive at the same conclusion as Freeman. Namely, that the confidence interval resulting from the two‐stage procedure should not be used.
ChemInform Abstract: Formation of Nets of Corner‐Shared Bicapped Gold Squares in SrAu3Ge: How a BaAl4‐Type Derivative Reconciles Fewer Valence Electrons and the Origin of Its Uniaxial Negative Thermal Expansion.
Authors: Lin Qisheng , Corbett John D.
Published: June 2012

SrAu3Ge is prepared from stoichiometric mixtures of the elements (Ta container, 700 °C for 6 h followed by annealing at 400 °C for 6 d, <85 vol% yield).
ChemInform Abstract: Hydrothermal Synthesis Map of Bismuth Titanates.
Authors: Sardar Kripasindhu , Walton Richard I.
Published: June 2012

The hydrothermal synthesis of four bismuth titanate materials from NaBiO3 and TiO2 (anatase) precursors under hydrothermal conditions is described.
ChemInform Abstract: New Light on an Old Reaction: Phase‐Transfer‐Catalyzed Intramolecular Cyclization of Propargyl Compounds for Synthesis of Indene Derivatives and Disubstituted Benzo[b]furans.
Authors: Sun Peng‐Shuai , Hu Jie , Wang Xiang‐Chuan , Liu Lei , Liang Yong‐Min
Published: June 2012

Compared with the expensive transitionmetal‐catalyzed reaction, the new method shows synthetic advantages in term of mild reaction conditions, environmentally friendly, and low cost.
ChemInform Abstract: An Efficient Copper(II)‐Catalyzed Direct Access to Primary Amides from Aldehydes under Neat Conditions.
Authors: Ganguly Nemai C. , Roy Sushmita , Mondal Pallab
Published: June 2012

The catalyst‐free method can be applied to a broad spectrum of aliphatic and aromatic aldehydes for successful amide formation.
ChemInform Abstract: One‐Pot Organocatalytic Tandem Aldol/Polycyclization Reactions Between 1,3‐Dicarbonyl Compounds and α,β,γ,δ‐Unsaturated Aldehydes for the Straightforward Assembly of Cyclopenta[b]furan‐Type Derivatives: New Insight into the Knoevenagel Reaction.
Authors: Riveira Martin J. , Mischne Mirta P.
Published: June 2012

For the reactions with the compounds (IIf), (XII), (XIV), and (XVII), 60% of the starting materials are recovered.
ChemInform Abstract: Palladium‐Catalyzed Suzuki—Miyaura Cross‐Coupling Reaction of Potassium 2‐Pyridyl Trifluoroborate with Aryl (Heteroaryl) Halides.
Authors: Ren Wei , Li Jingya , Zou Dapeng , Wu Yangjie , Wu Yusheng
Published: June 2012

The catalytic system efficiently promotes the process.
ChemInform Abstract: 1‐(Trimethylsilyl)vinyllithium
Authors: Labrecque Denis , Chan Tak‐Hang
Published: June 2012

Review: 68 refs.
ChemInform Abstract: (E)‐1‐Trimethylsilyl‐2‐trimethylstannylethylene
Authors: Moriarty Kevin J.
Published: June 2012

Review: 15 refs.
ChemInform Abstract: Chlorotri‐2‐propen‐1‐yl‐silane
Authors: Smith Craig R.
Published: June 2012

Review: 45 refs.
ChemInform Abstract: Gold‐Nanoparticle‐Enabled Biological and Chemical Detection and Analysis
Authors: Jans Hilde , Huo Qun
Published: June 2012

Review: 151 refs.
Health status of adolescent and young adult cancer survivors
Authors: Tai Eric , Buchanan Natasha , Townsend Julie , Fairley Temeika , Moore Angela , Richardson Lisa C.
Published: June 2012

BACKGROUND:

Adolescents and young adults (AYA) ages 15 to 29 years who are diagnosed with cancer are at risk for long‐term morbidity and mortality associated with treatment of their cancer and the cancer itself. In this article, the authors describe the self‐reported health status of AYA cancer survivors.

METHODS:

The authors examined 2009 data from the Behavioral Risk Factor Surveillance System, including demographic characteristics, risk behaviors, chronic conditions, health status, and health care access, among AYA cancer survivors compared with respondents who had no history of cancer.

RESULTS:

The authors identified 4054 AYA cancer survivors and 345,592 respondents who had no history of cancer. AYA cancer survivors, compared with respondents who had no history of cancer, reported a significantly higher prevalence of current smoking (26% vs 18%); obesity (31% vs 27%); chronic conditions, including cardiovascular disease (14% vs 7%), hypertension (35% vs 29%), asthma (15% vs 8%), disability (36% vs 18%), and poor mental health (20% vs 10%) and physical health (24% vs 10%); and not receiving medical care because of cost (24% vs 15%).

CONCLUSIONS:

AYA cancer survivors commonly reported adverse behavioral, medical, and health care access characteristics that may lead to poor long‐term medical and psychosocial outcomes. Increased adherence to established follow‐up guidelines may lead to improved health among AYA cancer survivors. Cancer 2012. © 2012 American Cancer Society.
Visual inputs to the mushroom body calyces of the whirligig beetle Dineutus sublineatus: Modality switching in an insect
Authors: Lin Chan , Strausfeld Nicholas J.
Published: June 2012

The mushroom bodies are prominent lobed centers in the forebrain, or protocerebrum, of most insects. Previous studies on mushroom bodies have focused on higher olfactory processing, including olfactory‐based learning and memory. Anatomical studies provide strong support that in terrestrial insects with mushroom bodies, the primary input region, or calyces, are predominantly supplied by olfactory projection neurons from the antennal lobe glomeruli. In aquatic species that generally lack antennal lobes, the calyces are vestigial or absent. Here we report an exception to this in the whirligig beetle Dineutus sublineatus (Coleoptera: Gyrinidae). This aquatic species lives on water and is equipped with two separate pairs of compound eyes, one pair viewing above and one viewing below the water surface. As in other aquatic insects, the whirligig beetle lacks antennal lobes, but unlike other aquatic insects its mushroom bodies possess robust calyces. Golgi impregnations and fluorescent tracer injections revealed that the calyces are exclusively supplied by visual neurons from the medulla of the dorsal eye optic lobes. No other sensory inputs reach the calyces, thereby showing a complete switch of calyx modality from olfaction to vision. Potential functions of the mushroom bodies of D. sublineatus are discussed in the context of the behavioral ecology of whirligig beetles. J. Comp. Neurol. 520:2562–2574, 2012. © 2012 Wiley Periodicals, Inc.
Female teneral mating in a monandrous species
Authors: Monceau Karine , Baaren Joan van
Published: June 2012

Schultesia nitor is a gregarious species living in Cacicus and Psarocolius ssp. pouch‐like nests. Due to gregariousness, opportunities for multiple copulations in both sexes are not supposed to be restricted. Females produce only one brood during their life and die within a few days following the birth of their nymphs, but this unique brood could be the result of either single or multiple mating events (i.e., monandry vs. polyandry). In this study, we first determined the age of sexual receptivity of both males and females. Larval development in this species is shorter in males than in females and thus, this species is protandric. Males were not able to copulate the day after emergence. Contrary to males, teneral females (i.e., females achieving their imaginal molt but not yet fully sclerotised and colored) were attractive and were able to mate with males. In the second experiment, we tested the existence of multiple matings in both sexes. Our results showed that females were monandrous whereas males were polygynous. Since we had observed that females were monoandrous, we expected them to be choosy and we determined their ability to discriminate between virgin and nonvirgin males. When given the choice, females preferred virgin males and overall, they were more successful at mating than experienced ones. Our results suggest that monandry may be primarily driven by the female’s short life‐span fecundity. The occurrence of teneral mating in this species calls into question the existence of a male strategy for monopolizing females, and as well as the implication of female choice. Although further work is required, this species provides an interesting model for understanding sexual conflicts.
C–C Coupling of Acyclic Nitronates with Silyl Ketene Acetals under Silyl Triflate Catalysis: Reactivity Umpolung of Aliphatic Nitro Compounds (Eur. J. Org. Chem. 18/2012)
Authors: Smirnov Vladimir O. , Khomutova Yulia A. , Tartakovsky Vladimir A. , Ioffe Sema L.
Published: June 2012

The cover picture shows the jet engine of a Fokker 100 in its ordinary and reverse thrust modes. These thrust modes closely resemble the chemistry of nitroalkenes when a new approach for the umpolung of their conventional reactivity is taken into account. Just like the deployment of the two buckets from the jet engine nozzle induces a reverse thrust, quenching of the negative charges on the two oxygen atoms of the nitronate anion with alkyl or silyl groups generates an electrophilic center on the former nucleophilic α‐carbon atom of the nitroalkane, which induces reversed reactivity. Details of this new approach are described in the article by V. O. Smirnov, S. L. Ioffe et al. on p. 3377 ff.

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Chip‐based nanoflow high performance liquid chromatography coupled to mass spectrometry for profiling of soybean flavonoids
Authors: Chang Yuwei , Zhao Chunxia , Wu Zeming , Zhou Jia , Zhao Sumin , Lu Xin , Xu Guowang
Published: June 2012

In this work a chip‐based nano HPLC coupled MS (HPLC‐chip/MS) method with a simple sample preparation procedure was developed for the flavonoid profiling of soybean. The analytical properties of the method including the linearity (R2, 0.992–0.995), reproducibility (RSD, 1.50–7.66%), intraday precision (RSD, 1.41–5.14%) and interday precision (RSD, 2.76–16.90%) were satisfactory. Compared with the conventional HPLC/MS method, a fast extraction and analysis procedure was applied and more flavonoids were detected in a single run. Additionally, 13 flavonoids in soybean seed were identified for the first time. The method was then applied to the profiling of six varieties of soybean sowed at the same place. A clear discrimination was observed among different cultivars, three isoflavones, accounting for nearly 80% of total flavonoid contents, were found increased in the spring soybeans compared with the summer cultivars.