bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship of non‐visualization of the fetal gallbladder and amniotic fluid digestive enzymes analysis to outcome
Authors: Dreux Sophie , Boughanim Mathias , Lepinard Catherine , Guichet Agnès , Rival Jean‐Marie , de Becdelievre Alix , Dugueperoux Ingrid , Muller Françoise 
Published: April 2012

ABSTRACTObjectiveThe aims of this study were evaluate the significance of non‐visualization of fetal gallbladder at routine ultrasound scan in a series of 102 cases and to determine the contribution of amniotic fluid digestive enzyme (AF‐DE) analysis towards the outcome.MethodThis is a multicenter retrospective study. Outcome of pregnancies, karyotype, and result of screening for CFTR gene mutations were known in all cases. Amniotic fluid gamma‐glutamyl‐transpeptidase and intestinal alkaline phosphatase isoenzyme were assayed.ResultsNon‐visualization of the fetal gallbladder was associated with a severe disease in 25 cases (cystic fibrosis in ten, biliary duct atresia in eight, digestive tract anomalies in six, and chromosomal anomaly in one). In the remaining 77 cases, gallbladder agenesis was diagnosed in 22, and in 55, the gallbladder was subsequently demonstrated. Before 22 weeks of gestation (n = 30), an abnormal AF‐DE pattern had a 90% sensitivity and 80% specificity in detecting cystic fibrosis or biliary duct atresia. After 22 weeks, sensitivity fell to 53%. The AF‐DE pattern was normal in 82% of gallbladder agenesis cases (benign) and in 91% of the cases where the gallbladder was subsequently detected.ConclusionNon‐visualization of the fetal gallbladder was associated with severe anomalies in 24% of cases. Prior to 22 weeks, determination of AF‐DE contributes to the prediction of biliary atresia or the presence of cystic fibrosis. © 2012 John Wiley & Sons, Ltd.
Discovery of epigenetic biomarkers for the noninvasive diagnosis of fetal disease
Authors: Bunce Kimberly , Chu Tianjiao , Surti Urvashi , Hogge William Allen , Peters David G. 
Published: April 2012

ABSTRACTObjectivesThe primary goal of this study was to identify CpG sites in the human genome that are differentially methylated in DNA obtained from chorionic villus sampling (CVS) samples and gestational age‐matched maternal blood cell (MBC) samples.MethodsWe used the HumanMethylation27 DNA Analysis BeadChip to characterize DNA methylation in samples of CVS and MBC. We then selected a subset of differentially methylated CpG sites on chromsome 13 and subjected them to analysis by mass spectrometry using the Epityper platform.ResultsWe identified 718 tissue‐specific differentially methylated regions (DMRs) between MBC and CVS; 563 of these were hypermethylated in MBC and hypomethylated in CVS, whereas 155 sites were hypomethylated in MBC and hypermethylated in CVS. Further analysis of 13 DMRs on chromosome 13 by Epityper confirmed the microarray data and provided us with additional data about the methylation patterns of surrounding CpG sites.ConclusionsAnalysis of the resulting data identified a large number of cytosine‐guanine dinucleotides that are potential biomarkers for the selective amplification of fetal DNA from maternal plasma and the subsequent noninvasive detection of trisomy 13. © 2012 John Wiley & Sons, Ltd.
Faculty as undergraduate research mentors for students of color: Taking into account the costs
Authors: Schwartz Joni 
Published: April 2012

AbstractThis article is based on the findings of a 2‐year study that examined the nature of effective faculty/student undergraduate research (UR) science, technology, engineering, and mathematics (STEM) relationships. The study site was a large urban public college where three fourths of all incoming freshmen receive need‐based aid; and although not a historically Black college or university (HBCU), 85% are students of color. The college offers 2‐ and 4‐year STEM degree programs. Utilizing cultural historical activity theory (CHAT) as both a theoretical and methodological framework, this phenomenological study employed semistructured interviews, written surveys, and member checking to understand four paired faculty/student UR mentoring relationships over 2 years. The findings not only concur with the bulk of UR research, indicating UR's promise for addressing the low enrollment and retention rates of students of color in the STEM disciplines but also raise issues around the emotional, financial, and professional costs to UR faculty. It is these costs that are the focus of this article that concludes with ideas, for university and college administrators and all others concerned, about on how we might support faculty in UR's crucial work toward the goal of retaining students of color in STEM. © 2012 Wiley Periodicals, Inc. Sci Ed 96:527–542, 2012
Mathematical models of morphogen gradients and their effects on gene expression
Authors: Shvartsman Stanislav Y. , Baker Ruth E. 
Published: April 2012

AbstractAn introduction to mathematical models of pattern formation by morphogen gradients is presented, using the early embryo of the fruit fly Drosophila as the main experimental example. Analysis of morphogen gradient formation is based on the source–diffusion–degradation models and a formalism of local accumulation times. Transcriptional control by morphogens is discussed within the framework of thermodynamic site occupancy models of gene regulatory regions. WIREs Dev Biol 2012 doi: 10.1002/wdev.55For further resources related to this article, please visit the WIREs website.
Production of leukotriene B4 by Paracoccidioides brasiliensis
Authors: Biondo Guilherme Augusto , Dias‐Melicio Luciane Alarcão , Bordon‐Graciani Ana Paula , Kurokawa Cilmery Suemi , de Campos Soares Angela Maria Victoriano 
Published: April 2012

AbstractParacoccidioides brasiliensis is the agent of paracoccidioidomycosis, the most prevalent deep mycosis in Latin America. The production of eicosanoids during fungal infection has been associated with the biology of these microorganisms and modulation of host immune response. The aim of our study was to evaluate whether P. brasiliensis strains with high or low virulence produce leukotriene B4 (LTB4), using endogenous and/or exogenous sources of arachidonic acid (AA). Moreover, we assessed whether this fungus might use the same metabolic pathway, described for mammalian cells, that involves the lipoxygenase (LOX) enzyme. The association between the production of this eicosanoid and fungus survival and growth was also evaluated. Our results showed that P. brasiliensis, irrespective of its virulence, produces high levels of LTB4 using endogenous AA. In addition, in cultures treated with exogenous AA, LTB4 levels were significantly higher, showing that this fungus also uses exogenous sources of fatty acids. Treatment with MK886, which blocks the activity of lipoxygenase, by inhibiting five‐lipoxygenase‐activating protein (FLAP) or with nordihydroguaiaretic acid (NDGA), a non‐selective lipoxygenase inhibitor, resulted in a significant reduction in LTB4 levels, indicating that the fungus produces this eicosanoid by using the LOX pathway or an enzyme with biochemically similar function. The significant reduction in viability detected in cultures treated with these inhibitors was, however, restored by adding exogenous LTB4, confirming the role of this eicosanoid in fungus survival. Moreover, the addition of LTB4 to cultures capable of producing LTs induces fungal growth. These results provide a foundation for additional studies on the contributions of LTB4 in P. brasiliensis virulence. Copyright © 2012 John Wiley & Sons, Ltd.
Diagnostic Value of FDG‐PET/CT for Lymph Node Metastasis of Colorectal Cancer
Authors: Kwak Jae Young , Kim Jae Seung , Kim Hye Jin , Ha Hyun Kwon , Yu Chang Sik , Kim Jin Cheon 
Published: April 2012

AbstractBackgroundLymph node metastasis is an important prognostic factor in patients with colorectal cancer. We assessed the ability of 18F‐fluorodeoxyglucose positron emission tomography/computed tomography (FDG‐PET/CT) to diagnose lymph node metastases in colorectal cancer patients.MethodsWe retrospectively analyzed the records of 473 patients who underwent preoperative FDG‐PET/CT, followed by curative surgery for colorectal cancer. Lymph node metastases were assessed as proximal or distal, depending on their anatomical location. We analyzed the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of FDG‐PET/CT and CT for detecting lymph node metastases.ResultsIn detecting proximal lymph nodes, FDG‐PET/CT had a sensitivity of 66 %, a specificity of 60 %, a PPV of 63 %, an NPV of 62 %, and an accuracy of 63 %; whereas CT had a sensitivity of 87 %, a specificity of 29 %, a PPV of 57 %, an NPV of 68 %, and an accuracy of 59 % (P = 0.245). FDG‐PET/CT and CT also showed similar accuracy in detecting distal lymph nodes (87 vs. 88 %, P = 0.620).ConclusionPreoperative FDG‐PET/CT and CT have comparable accuracy in detecting lymph node metastases of colorectal cancer.
Early versus Delayed Imaginal Exposure for the Treatment of Posttraumatic Stress Disorder Following Accidental Upper Extremity Injury
Authors: Weis Jo M. , Grunert Brad K. , Christianson Heidi Fowell 
Published: April 2012

Background The consequences following work-related injuries are far reaching, which are in part due to unrecognized and untreated posttraumatic stress disorder (PTSD). Imaginal exposure is a frequently used cognitive behavioral approach for the treatment of PTSD. This study examined the impact of early versus delayed treatment with imaginal exposure on amelioration of PTSD symptomatology in individuals who suffered upper extremity injuries. Methods Sixty individuals who suffered severe work-related injuries received standard, non-randomly assigned psychological treatment for PTSD (e.g., prolonged imaginal exposure) either early (30–60 days) or delayed (greater than 120 days) following severe work-related upper extremity injury. Nine measures of various components of PTSD symptomatology were administered at onset of treatment, end of treatment, and at 6-month follow-up evaluations. Results Patients showed significant treatment outcomes at all three measurement intervals in both the early and delayed groups demonstrating that Prolonged Imaginal Exposure is an appropriate treatment for persons diagnosed with PTSD. In addition, there was no difference in return to work status between the early and the delayed treatment groups. However, the early treatment group required significantly fewer treatment sessions than the delayed treatment group. Conclusions Results supported the utility of imaginal exposure and the need for early assessment and referral for those diagnosed with PTSD following upper extremity injuries.
Mediation analysis and categorical variables: The final frontier
Authors: Iacobucci Dawn 
Published: April 2012

AbstractMany scholars are interested in understanding the process by which an independent variable affects a dependent variable, perhaps in part directly and perhaps in part indirectly, occurring through the activation of a mediator. Researchers are facile at testing for mediation when all the variables are continuous, but a definitive answer had been lacking heretofore as to how to analyze the data when the mediator or dependent variable is categorical. This paper describes the problems that arise as well as the potential solutions. In the end, a solution is recommended that is both optimal in its statistical qualities as well as practical and easily implemented: computezMediation.
Mediation analysis and categorical variables: Some further frontiers
Authors: Feinberg Fred M. 
Published: April 2012

AbstractIacobucci (2012) provides a conceptually appealing, readily implemented measure to assess mediation for a far wider range of data type combinations than traditional OLS‐based analyses permit. Here, we consider potential applications and extensions along several lines, particularly in terms of random utility models, simulation‐based estimation, and potential nonlinearities, as well as some methodological and cultural impediments.
Mediation with categorical variables compleat
Authors: Iacobucci Dawn 
Published: April 2012

AbstractThis rejoinder addresses the thoughtful issues raised by the commentators. We hold to the analytical solution of fitting X → M (to obtain a and sa) and X&M→ (to obtain b and sb) via regression or logistic regression, depending on whether M and Y are continuous or categorical. Then researchers compute za, zb, and ZMediation.
Matched asymptotic solutions for turbulent plumes
Authors: Candelier Fabien , Vauquelin Olivier 
Published: April 2012

AbstractRecent analytical investigations have shown that the vertical evolution of turbulent plumes variables can be derived straightforwardly from the knowledge of a single function $\Gamma (z)$ (called the plume function) which is the solution of a nonlinear differential equation. This article presents matched asymptotic solutions of this equation in the cases corresponding to highly lazy or highly forced plumes. First, it is shown that, far from the source, the asymptotic expression of the plume function can be derived by means of a perturbation method based on a Padé-like approximation. The resulting outer solution is invariant under translation (with respect to the vertical coordinate) so that we are led to the classical problem concerning the location of the plume (asymptotic) virtual origin. In order to determine this virtual origin location as a function of the conditions at the source, the far-field asymptotic solution is matched to an inner expansion of the solution which is valid near the source. Comparisons between these asymptotic solutions and numerical results are finally made in order to test their validity.
First discovery of Early PalaeozoicBathysiphon(Foraminifera) – test structure and habitat of a ‘living fossil’
Authors: LANDING ED , REYES SANDRA PATRUCCO , ANDREAS AMANDA L. , BOWSER SAMUEL S. 
Published: April 2012

AbstractThe giant, agglutinated foraminiferanBathysiphonSars, previously Triassic–Recent, occurs in much older sedimentary rock (Early Ordovician, late early Tremadocian) of Avalonia. The genus extends back toc. 485 Ma based on its discovery in platform mudstone of the Chesley Drive Group in Cape Breton Island, Nova Scotia. Elongate (up to 60 mm), epibenthicBathysiphontubes occur in wave-rippled, green-grey mudstone with a low diversity, probably dysoxic fauna. The mudstone is coeval with and lithologically similar to the Shineton Formation in Shropshire and the Welsh Borderlands. Scanning microscopy of theBathysiphonwalls shows imbricated mica grains that parallel the long axis of the tests. The lumen has a mélange of packed sediment grains, some of which are spherical structures of siliciclastic mud studded with tetrahedral pyrite crystals. A felt-like, agglutinated test, a lumen packed with spherical structures (probable stercomata) and the domal ends of some specimens are consistent with modernBathysiphon. This report is the first time that cytoplasmic activity and stercomata formation have been used to refer fossil protists to a modern group.Bathysiphondiffers from the Cambrian foraminiferanPlatysolenitesPander, which has an open lumen without stercomata, but support a comparable, sediment deposit-feeding niche.Bathysiphonis truly a ‘living fossil’, with a mode of test construction, cytoplasmic activity that formed stercomata and a niche unchanged for almost 500 million years. Foraminiferans have not been found prior to the Cambrian Period, and the Early Cambrian appearance of agglutinated foraminiferans is part of the radiation of Phanerozoic communities.
Methane reduction and energy partitioning in goats fed two concentrations of tannin from Mimosa spp.
Authors: BHATTA R. , ENISHI O. , YABUMOTO Y. , NONAKA I. , TAKUSARI N. , HIGUCHI K. , TAJIMA K. , TAKENAKA A. , KURIHARA M. 
Published: April 2012

SUMMARYDietary manipulation is one promising approach to reducing methane (CH4) emissions from forage-fed ruminants. Studies were conducted to evaluate the effects of feeding two concentrations of tannins from Mimosa spp. on rumen fermentation, methanogenesis and energy partitioning in goats. Adult male goats were used in three trials where three diets with increasing concentrations of tannins (control, low-tannin and high-tannin) were fed in a switch-over design. The control diet consisted of 0·65 timothy hay, 0·20 crushed maize and 0·15 soybean meal; low- and high-tannin diets contained 0·975 and 0·950 of the control diet, respectively, mixed with 0·025 and 0·050 of a commercial compound containing tannins with mean crude protein (CP) of 147 g/kg dry matter (DM) and gross energy (GE) 19 MJ/kg DM, respectively. Total contents (DM basis) of tannins (hydrolysable and condensed) in the control, low- and high-tannin diets were 0, 2·8 and 5·6 g/kg DM, respectively. The tannin source contained 37 and 76 g/kg DM of condensed and hydrolysable tannins, respectively (DM basis). The DM (664 g/d) and GE intakes (19·0 MJ/d) were similar among diet groups. Digestibilities of all dietary components in the high-tannin diet were lower (P < 0·05) than low-tannin and control diets. The faecal energy (MJ/d) output was lowest in the control diet (3·49) and increased (P < 0·05) in tannin-fed goats (3·80; 4·87) resulting in a corresponding decrease in digestible energy (DE). Methane emission, expressed both on absolute and per unit of feed intake basis, decreased (P < 0·05) with increasing concentration of tannins in the diet. For example, CH4 energy excretion was 0·98, 0·87 and 0·76 MJ/d for goats on control, low- and high-tannin diets, respectively, whereas their corresponding values for CH4 conversion ratio were 0·079, 0·069 and 0·060 of GE intake. These results suggest that natural tannins, even at a low concentration (2·8 g/kg DM of the diet), reduce CH4 emissions, and tree leaves containing appreciable amounts of tannins may potentially be exploited as natural feed additives in ruminants.
Salivary duct carcinoma: what is already known, and can we improve survival?
Authors: Wee D T H , Thomas A A , Bradley P J 
Published: April 2012

AbstractSalivary duct carcinoma is an aggressive malignancy with a high mortality rate, which phenotypically resembles high-grade breast ductal carcinoma. The parotid gland is the most common location. Standard treatment is surgery to the primary tumour together with post-operative radiotherapy. Despite this, there is a high rate of local recurrence, cervical nodal involvement and distant metastasis. Chemotherapy is currently considered only for end-stage, disseminated disease; however, current evidence indicates that chemotherapy used with radiotherapy may result in improved disease control and survival.Human epidermal growth factor receptor-2 is a proto-oncogene which is over-expressed in both breast ductal carcinoma and salivary duct carcinoma. Clinical studies of patients with metastatic breast cancer, using trastuzumab, a monoclonal antibody directed against human epidermal growth factor receptor-2, have shown significant efficacy in tumour response, resulting in improved survival. Such advances in immunohistochemistry, and in targeted immunotherapy for breast ductal carcinoma, should be applied to the treatment of salivary duct carcinoma.
La Economía de Santafé de Bogotá En 1810
Authors: Kalmanovitz Salomón , Rivera Edwin López 
Published: April 2012

AbstractThis essay shows that the growth of the economy of New Granada during the Eighteenth Century made an important impact on its political center, Santafé de Bogota, at least until 1808. Such prosperity was the result of a process of specialization and division of labor between different regions of the new kingdom, derived from the dynamics of gold mining that gave a strong impulse to Santafé's economy as a trade center for the handicraft production of Eastern Colombia and the fertile savanna surrounding it, which was a net food exporter. The Mint established in Santafé, which was a de facto monopoly, attracted merchants and miners who established there a center for the exchange of gold dust for coin.
Demography ofCycas micronesicaon Guam following introduction of the armoured scaleAulacaspis yasumatsui
Authors: Marler Thomas E. , Lawrence John H. 
Published: April 2012

Abstract:Following the 2003 invasion of the armoured scaleAulacaspis yasumatsuito Guam, changes to population traits of the dominantCycas micronesicawere determined. Belt transects with a width of 4 m and an average length of 120 m were established in October 2004 to document plant mortality until January 2011. Stem height, basal diameter and leaf number were also measured for each plant and used to determine density, demography and allometric relationships. Allometric traits and a left-skewed demographic structure of the pre-invasionC. micronesicahabitat documented a thriving population with high recruitment potential.Aulacaspis yasumatsuidispersed into the study site 4 mo after the initial census. All seedlings were killed within 9 mo and all juvenile plants were killed within 40 ± 10 mo. Mortality reached 92% by 6 y after chronic scale infestations. Allometry and demography of the 2011 survivors described a collapsingC. micronesicapopulation of stressed and reproductively challenged trees with no recruitment. This classic example of the enemy release hypothesis has resulted in a homogeneous decline in plant density from 2007–2011. The trend predicts extirpation ofC. micronesicafrom west Guam habitats by 2019.
Heavy impact on seedlings by the impala suggests a central role in woodland dynamics
Authors: O'Kane Christopher A. J. , Duffy Kevin J. , Page Bruce R. , Macdonald David W. 
Published: April 2012

Abstract:Research has increasingly established that mesoherbivores influence the regeneration of woody plants. However the relationship between mesoherbivore density and degree of impact, and the spatial component of this impact, has not been well established. Using a novel sampling design, we assessed in iMfolozi Park, South Africa, the impact of impala (Aepyceros melampus) across the full complement of woody species within the home range, evaluating its spatial component and relationship to impala density. We used four GPS collars, in separate breeding herds, and a GIS to detect zones of different density of impala in the landscape, thus defining a fine-grain browsing gradient. We assessed impact on woody recruits (≤ 0.5 m height) across this gradient by means of 1600 random 1 × 1-m quadrats. Densities of woody seedlings, and mean percentage of remaining canopy, were significantly less in areas of high impala density versus low-density areas. There was a significant correlation between increasing impala density and decreasing density of favoured woody recruits. We propose a hypothesis of impala-induced patch dynamics. It seems likely that the ubiquitous impala may create and sustain a shifting mosaic of patches, and thus function as a key determinant of landscape heterogeneity.
Species diversity of bats along an altitudinal gradient on Mount Mulanje, southern Malawi
Authors: Curran Michael , Kopp Mirjam , Beck Jan , Fahr Jakob 
Published: April 2012

Abstract:A climate model, based on effects of water availability and temperature, was recently proposed to explain global variation in bat species richness along altitudinal gradients. Yet such studies are sparse in the tropics and near-absent in Africa. Here we present results from an altitudinal study of bat diversity from Mount Mulanje, Malawi. Using ground nets, canopy nets and harp traps, we sampled eight sites across three habitat zones from 630 m to 2010 m asl. We assessed the influence of climatic, geographic and biotic variables on measures of estimated species richness, Fisher's α, and an unbiased index of compositional turnover. We recorded 723 individuals and 30 species along the gradient, revealing a ‘low plateau’ pattern in estimated species richness, peaking at 1220 m, which is congruent with the global climate model. Measures of local habitat structure significantly explained a large degree of variation in species richness and compositional turnover between sites. Fisher's α was further significantly correlated to mean annual relative humidity, suggesting a background climatic influence.