bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproductive traits associated with species turnover of amphibians in Amazonia and its Andean slopes
Authors: Jiménez‐Robles Octavio , Guayasamin Juan M. , Ron Santiago R. , De la Riva Ignacio
Published: March 2017

Assembly of ecological communities is important for the conservation of ecosystems, predicting perturbation impacts, and understanding the origin and loss of biodiversity. We tested how amphibian communities are assembled by neutral and niche‐based mechanisms, such as habitat filtering. Species richness, β‐diversities, and reproductive traits of amphibians were evaluated at local scale in seven habitats at different elevation and disturbance levels in Wisui Biological Station, Morona‐Santiago, Ecuador, on the foothills of the Cordillera del Kutukú; and at regional scale using 109 localities across evergreen forests of Amazonia and its Andean slopes (0–3,900 m a.s.l.). At local scale, species composition showed strong differences among habitats, explained mainly by turnover. Reproductive modes occurred differently across habitats (e.g., prevalence of direct developers at high elevation, where breeding in ground level water disappears). At regional scale, elevation was the most important factor explaining the changes in species richness, reproductive trait occurrences, and biotic dissimilarities. Species number in all groups decreased with elevation except for those with lotic tadpoles and terrestrial reproduction stages. Seasonality, annual precipitation, and relative humidity partially explained the occurrence of some reproductive traits. Biotic dissimilarities were also mostly caused by turnover rather than nestedness and were particularly high in montane and foothill sites. Within lowlands, geographic distance explained more variability than elevation. Habitat filtering was supported by the different occurrence of reproductive traits according to elevation, water availability, and breeding microhabitats at both scales, as well as other assembly mechanisms based in biotic interactions at local scale. Human‐generated land use changes in Amazonia and its Andean slopes reduce local amphibian biodiversity by alteration of primary forests and loss of their microhabitats and the interaction network that maintains their unique amphibian assemblages with different reproductive strategies.
Incipient ecological speciation between successional varieties of a dominant tree involves intrinsic postzygotic isolating barriers
Authors: Stacy Elizabeth A. , Paritosh Bhama , Johnson Melissa A. , Price Donald K.
Published: March 2017

Whereas disruptive selection imposed by heterogeneous environments can lead to the evolution of extrinsic isolating barriers between diverging populations, the evolution of intrinsic postzygotic barriers through divergent selection is less certain. Long‐lived species such as trees may be especially slow to evolve intrinsic isolating barriers. We examined postpollination reproductive isolating barriers below the species boundary, in an ephemeral hybrid zone between two successional varieties of the landscape‐dominant Hawaiian tree, Metrosideros polymorpha, on volcanically active Hawai'i Island. These archipelago‐wide sympatric varieties show the weakest neutral genetic divergence of any taxon pair on Hawai'i Island but significant morphological and ecological differentiation consistent with adaptation to new and old lava flows. Cross‐fertility between varieties was high and included heterosis of F1 hybrids at the seed germination stage, consistent with a substantial genetic load apparent within varieties through low self‐fertility and a lack of self‐pollen discrimination. However, a partial, but significant, barrier was observed in the form of reduced female and male fertility of hybrids, especially backcross hybrids, consistent with the accumulation of genetic incompatibilities between varieties. These results suggest that partial intrinsic postzygotic barriers can arise through disruptive selection acting on large, hybridizing populations of a long‐lived species.
Heart failure with mid‐range ejection fraction: a distinct clinical entity? Insights from the Trial of Intensified versus standard Medical therapy in Elderly patients with Congestive Heart Failure (TIME‐CHF)
Authors: Rickenbacher Peter , Kaufmann Beat A. , Maeder Micha T. , Bernheim Alain , Goetschalckx Kaatje , Pfister Otmar , Pfisterer Matthias , Brunner‐La Rocca Hans‐Peter ,   for the TIME‐CHF Investigators
Published: March 2017

Aims

While the conditions of heart failure (HF) with reduced (HFrEF, LVEF < 40%) and preserved (HFpEF, LVEF ≥ 50%) left ventricular ejection fraction (LVEF) are well characterized, it is unknown whether patients with HF and mid‐range LVEF (HFmrEF, LVEF 40–49%) have to be regarded as a separate clinical entity. The aim of this study was to characterize these three populations and to compare outcome and response to therapy.

Methods and results

The analysis was based on the Trial of Intensified versus standard Medical therapy in Elderly patients with Congestive Heart Failure (TIME‐CHF) comprising a population with established HF including the whole spectrum of LVEF. Of the 622 patients, 108 (17%) were classified as having HFmrEF. This group was in general found to be ‘intermediate’ regarding clinical characteristics with a comparable and high burden of comorbidities and equally impaired quality of life but was more likely to have coronary artery disease as compared with the HFpEF group. During a median follow‐up of 794 days, mortality was 39.7% without significant differences between groups. N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP)‐guided as compared with standard therapy resulted in improved survival free of HF hospitalizations in HFrEF and HFmrEF, but not in HFpEF.

Conclusion

Although the ‘intermediate’ clinical profile of HFmrEF between HFrEF and HFpEF would support the conclusion that HFmrEF is a distinct clinical entity, we hypothesize that HFmrEF has to be categorized as HFrEF because of the high prevalence of coronary artery disease and the similar benefit of NT‐proBNP‐guided therapy in HFrEF and HFmrEF, in contrast to HFpEF.
IFN‐γ directly inhibits murine B‐cell precursor leukemia‐initiating cell proliferation early in life
Authors: Fidanza Mario , Seif Alix E. , Jo Sumin , Kariminia Amina , Rolf Nina , Sly Laura M. , Grupp Stephan A. , Reid Gregor S. D.
Published: March 2017

The early‐life immune environment has been implicated as a modulator of acute lymphoblastic leukemia (ALL) development in children, with infection being associated with significant changes in ALL risk. Furthermore, polymorphisms in several cytokine genes, including IL‐10 and IFN‐γ, are associated with leukemia development. However, the mechanisms and timing of these influences remain unknown. Here, we use the Eμ‐ret transgenic mouse model of B‐cell precursor ALL to assess the influence of IFN‐γ on the early‐life burden of leukemia‐initiating cells. The absence of IFN‐γ activity resulted in greater numbers of leukemia‐initiating cells early in life and was associated with accelerated leukemia onset. The leukemia‐initiating cells from IFN‐γ‐knockout mice had reduced suppressor of cytokine signaling (SOCS‐1) expression, were significantly more sensitive to IFN‐γ, and exhibited more rapid expansion in vivo than their wild‐type counterparts. However, sensitivity to this inhibitory pathway was lost in fully transformed IFN‐γ‐knockout leukemia cells. These results demonstrate that the influence of IFN‐γ on ALL progression may not be mediated by selection of nascent transformed cells but rather through a general SOCS‐mediated reduction in B‐cell precursor proliferation. Thus, while cytokine levels may influence leukemia at multiple points during disease progression, our study indicates a significant early influence of basal, infection‐independent cytokine production on leukemogenesis.
Monitoring chemical and biological recovery at a confined aquatic disposal site, Oslofjord, Norway
Authors: Oen Amy M.P. , Pettersen Arne , Eek Espen , Glette Tormod , Brooks Lucy , Breedveld Gijs D.
Published: March 2017

The recovery of the confined aquatic disposal (CAD) facility located at Malmøykalven in Oslofjord, Norway, has been assessed using an array of field measurement techniques. These methods were used prior to the disposal of dredged sediments as well as during 3 annual postdisposal monitoring campaigns. Traditional sampling to assess chemical recovery indicates that an immediate reduction in total sediment concentrations and surface sediments can be characterized as having good quality. Deposition of new material indicates that the quality of depositing material at the CAD is stabile and representative of the natural background quality in the area. Continued deposition of this material will improve the long-term chemical recovery of the CAD. A positive biological recovery of the benthic community has been observed and is expected to continue along a typical benthic succession pattern. To supplement traditional sampling, passive samplers were deployed at the CAD. Results suggest that the flux and concentrations of polycyclic aromatic hydrocarbon 16 and polychlorinated biphenyl 7 released from the CAD will continue to decrease over time. The combined results from these multiple lines of evidence indicate that the CAD and capping layer function as predicted 3 yr after the construction was completed. There is not only an improvement in the efficacy of the CAD itself but also a general improvement of the area, compared with the situation prior to disposal. Environ Toxicol Chem 2017;36:2552–2559. © 2017 SETAC
The Methods and Tools of Improvement Science
Authors: Lemire Sebastian , Christie Christina A. , Inkelas Moira
Published: March 2017

Rooted in ideas from operations research in the 1930s, improvement science bloomed in the healthcare literature during the 1990s and has since then spread rapidly across fields such as management, social work, behavioral economics, and most recently education (Lewis, ). So what is thing called “improvement science”? What is the intellectual foundation of improvement science? And what does it look like in real‐world applications? What, if anything, might we, as evaluators, learn from the techniques and tools of improvement science? These are questions that will be addressed in this chapter.
Can we predict subject‐specific dynamic cortical thickness maps during infancy from birth?
Authors: Meng Yu , Li Gang , Rekik Islem , Zhang Han , Gao Yaozong , Lin Weili , Shen Dinggang
Published: March 2017

Understanding the early dynamic development of the human cerebral cortex remains a challenging problem. Cortical thickness, as one of the most important morphological attributes of the cerebral cortex, is a sensitive indicator for both normal neurodevelopment and neuropsychiatric disorders, but its early postnatal development remains largely unexplored. In this study, we investigate a key question in neurodevelopmental science: can we predict the future dynamic development of cortical thickness map in an individual infant based on its available MRI data at birth? If this is possible, we might be able to better model and understand the early brain development and also early detect abnormal brain development during infancy. To this end, we develop a novel learning‐based method, called Dynamically‐Assembled Regression Forest (DARF), to predict the development of the cortical thickness map during the first postnatal year, based on neonatal MRI features. We applied our method to 15 healthy infants and predicted their cortical thickness maps at 3, 6, 9, and 12 months of age, with respectively mean absolute errors of 0.209 mm, 0.332 mm, 0.340 mm, and 0.321 mm. Moreover, we found that the prediction precision is region‐specific, with high precision in the unimodal cortex and relatively low precision in the high‐order association cortex, which may be associated with their differential developmental patterns. Additional experiments also suggest that using more early time points for prediction can further significantly improve the prediction accuracy. Hum Brain Mapp 38:2865–2874, 2017. © 2017 Wiley Periodicals, Inc.
Functional organization of the human posterior cingulate cortex, revealed by multiple connectivity‐based parcellation methods
Authors: Cha Jungho , Jo Hang Joon , Gibson William S. , Lee Jong‐Min
Published: March 2017

Based on cytoarchitecture, the posterior cingulate cortex (PCC) is thought to be comprised of two distinct functional subregions: the dorsal and ventral PCC (dPCC and vPCC). However, functional subregions do not completely match anatomical boundaries in the human brain. To understand the relationship between the functional organization of regions and anatomical features, it is necessary to apply parcellation algorithms based on functional properties. We therefore defined functionally informed subregions in the human PCC by parcellation of regions with similar patterns of functional connectivity in the resting brain. We used various patterns of functional connectivity, namely local, whole‐brain and diffuse functional connections of the PCC, and various clustering methods, namely hierarchical, spectral, andk‐means clustering to investigate the subregions of the PCC. Overall, the approximate anatomical boundaries and predicted functional regions were highly overlapped to each other. Using hierarchical clustering, the PCC could be clearly separated into two anatomical subregions, namely the dPCC and vPCC, and further divided into four subregions segregated by local functional connectivity patterns. We show that the PCC could be separated into two (dPCC and vPCC) or four subregions based on local functional connections and hierarchical clustering, and that subregions of PCC display differential global functional connectivity, particularly along the dorsal‐ventral axis. These results suggest that differences in functional connectivity between dPCC and vPCC may be due to differences in local connectivity between these functionally hierarchical subregions of the PCC.Hum Brain Mapp 38:2808–2818, 2017. ©2017 Wiley Periodicals, Inc.
Down‐regulation of hepatocyte nuclear factor‐4α and defective zonation in livers expressing mutant Z α1‐antitrypsin
Authors: Piccolo Pasquale , Annunziata Patrizia , Soria Leandro R. , Attanasio Sergio , Barbato Anna , Castello Raffaele , Carissimo Annamaria , Quagliata Luca , Terracciano Luigi M. , Brunetti‐Pierri Nicola
Published: March 2017

α1‐Antitrypsin (AAT) deficiency is one of the most common genetic disorders and the liver disease due to the Z mutant of AAT (ATZ) is a prototype of conformational disorder due to protein misfolding with consequent aberrant intermolecular protein aggregation. In the present study, we found that livers of PiZ transgenic mice expressing human ATZ have altered expression of a network of hepatocyte transcriptional factors, including hepatocyte nuclear factor‐4α, that is early down‐regulated and induces a transcriptional repression of ATZ expression. Reduced hepatocyte nuclear factor‐4α was associated with activation of β‐catenin, which regulates liver zonation. Livers of PiZ mice and human patients with AAT deficiency were both found to have a severe perturbation of liver zonation. Functionally, PiZ mice showed a severe defect of ureagenesis, as shown by increased baseline ammonia, and reduced urea production and survival after an ammonia challenge. Down‐regulation of hepatocyte nuclear factor‐4α expression and defective zonation in livers have not been recognized so far as features of the liver disease caused by ATZ and are likely involved in metabolic disturbances and in the increased risk of hepatocellular carcinoma in patients with AAT deficiency. Conclusion: The findings of this study are consistent with the concept that abnormal AAT protein conformation and intrahepatic accumulation have broad effects on metabolic liver functions. (Hepatology 2017;66:124–135).
Genital Mycoplasma infection among Mexican women with systemic lupus erythematosus
Authors: Méndez‐Martínez Socorro , García‐Carrasco Mario , Cedillo‐Ramírez María L. , Mendoza‐Pinto Claudia , Etchegaray‐Morales Ivet , Gil‐Juárez Constantino , Montiel‐Jarquín Álvaro J. , Taboada‐Cole Alejandro , Jiménez‐Herrera Erick A. , Muñóz‐Guarneros Margarita , Cervera Ricard
Published: March 2017

Objective

To assess the prevalence of genital Mycoplasma spp. among women with systemic lupus erythematosus (SLE) and to identify factors associated with such infection.

Methods

A cross‐sectional study was conducted among patients with SLE and healthy women who attended a hospital in Puebla, Mexico, between July 29, 2014, and January 4, 2015. All participants were aged 18 years or older and sexually active. A structured interview assessed sociodemographic, obstetric, gynecologic, and clinical characteristics. Disease activity was evaluated using the Mexican SLE Disease Activity Index. Polymerase chain reaction was used to detect the presence of Mycoplasma spp. in genital samples.

Results

Ureaplasma urealyticum was the only genital mycoplasma detected; it was present in 32 (24.6%) of 130 patients with SLE and 12 (12.8%) of 94 healthy women. Patients with SLE had increased odds of infection (odds ratio 2.120, 95% confidence interval 1.046–4.296). Among patients with SLE, multiparity was more common in those with U. urealyticum infection (P=0.043).

Conclusion

One‐quarter of women with SLE had genital infection with U. urealyticum. An association was found between infection and multiparity among women with SLE.
The Estimation of Second-Generation HR-pQCT From First-Generation HR-pQCT Using In Vivo Cross-Calibration
Authors: Manske Sarah L , Davison Erin M , Burt Lauren A , Raymond Duncan A , Boyd Steven K
Published: March 2017

Second-generation high-resolution peripheral quantitative computed tomography (HR-pQCT) provides the highest resolution in vivo to assess bone density and microarchitecture in 3D. Although strong agreement of most outcomes measured with first- (XCTI) and second- (XCTII) generation HR-pQCT has been demonstrated, the ability to use the two systems interchangeably is unknown. From in vivo measurements, we determined the limits of estimating XCTII data from XCTI scans conducted in vivo and whether that estimation can be improved by linear cross-calibration equations. These data are crucial as the research field transitions to the new technology. Our study design established cross-calibration equations by scanning 62 individuals on both systems on the same day and then tested those cross-calibrations on the same cohort 6 months later so that estimated (denoted as XCTII*) and “true” XCTII parameters could be compared. We calculated the generalized least-significant change (GLSC) for those predictions. There was strong agreement between both systems for density (R2 > 0.94), macroarchitecture (R2 > 0.95), and most microarchitecture outcomes with the exception of trabecular thickness (Tb.Th, R2 = 0.51 to 0.67). Linear regression equations largely eliminated the systematic error between XCTII and XCTII* and produced a good estimation of most outcomes, with individual error estimates between 0.2% and 3.4%, with the exception of Tt.BMD. Between-system GLSC was similar to within-XCTI LSC (eg, 8.3 to 41.9 mg HA/cm3 for density outcomes). We found that differences between outcomes assessed with XCTI and XCTII can be largely eliminated by cross-calibration. Tb.Th is poorly estimated because it is measured more accurately by XCTII than XCTI. It may be possible to use cross-calibration for most outcomes when both scanner generations are used for multicenter and longitudinal studies. © 2017 American Society for Bone and Mineral Research.
Probiotics are a good choice in remission of inflammatory bowel diseases: A meta analysis and systematic review
Authors: Ganji‐Arjenaki Mahboube , Rafieian‐Kopaei Mahmoud
Published: March 2017

Altered gut bacteria and bacterial metabolic pathways are two important factors in initiation and progression of inflammatory bowel disease (IBD). However, efficacy of probiotics in remission of patients with IBD has not been characterized. This study was performed on the studies that specifically assessed the efficacy of probiotics in attaining clinical response on patients with various types of IBD. The efficacy of variant species of probiotics in different conditions and the influence of study quality in outcomes of randomized controlled trials (RCTs) were also assessed. The RCTs were collected by searching in MEDLINE Web of Science and Google scholar. Then all studies were abstracted in abstraction form and the outcomes were analyzed with fixed‐effect and mixed‐effect models for assessment of efficacy of variant species of probiotics in subgroups of IBDs. Analysis of 9 trials showed that probiotics had not significant effect on Crohn's disease (CD) (p = 0.07) but analysis of 3 trials in children with IBD revealed a significant advantage (p < 0.01). Analysis of 18 trials revealed that probiotics in patients with Ulcerative colitis (UC) in different conditions have significant effects (p = 0.007). VSL#3 probiotics in patients with UC had significant effect (p < 0.01). Combination of Lactobacillus probiotic, prebiotics had significant effect (p = 0.03) only in patients with UC. Combination of Saccharomyces boulardii, Lactobacillus, and VSL#3 probiotics in CD had also a trend for efficiency (p = 0.057). In children with IBD, the combination of Lactobacillus with VSL#3 probiotics had significant effect (p < 0.01). Probiotics are beneficial in IBD, especially the combination ones in UC.
In situ and post‐synthesis immobilization of enzymes on nanocrystalline MOF platforms to yield active biocatalysts
Authors: Gascón Victoria , Castro‐Miguel Elsa , Díaz‐García Manuel , Blanco Rosa M , Sanchez‐Sanchez Manuel
Published: March 2017

BACKGROUND

Very recently, metal‐organic framework (MOF) materials have been postulated as emerging supports to achieve solid‐state enzyme‐contained biocatalysts. In this work, post‐synthesis and in situ strategies to immobilize β‐glucosidase and laccase on different MOF materials were studied. The MOF‐based supports, i.e. MIL‐53(Al), NH2‐MIL‐53(Al) and Mg‐MOF‐74, were prepared under soft and sustainable conditions (room temperature and pH values compatible with enzymatic activity), allowing development of the in situ strategy.

RESULTS

In both post‐synthesis and in situ approaches, the intercrystalline mesoporosity of the MOF‐based support favored the immobilization efficiency or the specific activity. The latter expressed as units per milligram of immobilized enzyme was higher in the post‐synthesis immobilization, whereas the biocatalysts prepared in situ gave much higher enzyme loading (over 85%) and lower enzyme leaching (around 5%). The in situ approach even worked in a non‐aqueous (N,N‐dimethylformamide) media in which the free enzyme was completely inactive. The immobilized enzymes are much larger than the structural pores of the MOFs.

CONCLUSIONS

Enzymes can be efficiently immobilized on nanocrystalline MOFs prepared under soft and sustainable conditions despite the supports lacking large enough pores to host the enzymes. The in situ approach is very efficient capturing enzymes and preserving some of their activity even under adverse conditions. © 2017 Society of Chemical Industry
A Green Synthesis of 2‐Amino‐4‐(9H‐carbazole‐3‐yl)thiophene‐3‐carbonitriles by a Step‐wise and One‐pot Three‐component Gewald Reaction
Authors: Avula Vijay Kumar Reddy , Vallela Swetha , Anireddy Jaya Shree , Chamarthi Naga Raju
Published: March 2017

An eco‐friendly method has been developed for the synthesis of 2‐amino‐4‐(9H‐carbazole‐3‐yl)thiophene‐3‐carbonitriles from preliminary carbazole (1) through an intermediate of 2‐(1‐(9H‐carbazole‐3‐yl)ethylidene)malononitriles using the Knoevenagel condensation followed by the Gewald reaction. On the other hand, the target compounds could also be prepared in a one‐pot three‐component manner by treating equimolar quantities of 1‐(9H‐carbazole‐3‐yl)ethanone (3), malononitrile, and elemental sulfur. The merits of this preparation are mild reaction conditions. The Gewald reaction is executed with inorganic base NaHCO3 (H2O) in tetrahydrofuran, easy work‐up procedure with good yields.
Diffusion tensor imaging MR neurography for the detection of polyneuropathy in type 1 diabetes
Authors: Vaeggemose Michael , Pham Mirko , Ringgaard Steffen , Tankisi Hatice , Ejskjaer Niels , Heiland Sabine , Poulsen Per L. , Andersen Henning
Published: March 2017

Purpose

To evaluate if diffusion tensor imaging MR neurography (DTI‐MRN) can detect lesions of peripheral nerves in patients with type 1 diabetes.

Materials and Methods

Eleven type 1 diabetic patients with polyneuropathy (DPN), 10 type 1 diabetic patients without polyneuropathy (nDPN), and 10 healthy controls (HC) were investigated with a 3T MRI scanner. Clinical examinations, nerve‐conduction studies, and vibratory‐perception thresholds determined the presence of DPN. DTI‐MRN (voxel size: 1.4 × 1.4 × 3 mm3; b‐values: 0, 800 s/mm2) covered proximal (sciatic nerve) and distal regions of the lower extremity (tibial nerve). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated and compared to T2‐relaxometry and proton‐spin density obtained from a multiecho turbo spin echo (TSE) sequence. Furthermore, we evaluated DTI reproducibility, repeatability, and diagnostic accuracy.

Results

DTI‐MRN could accurately discriminate between DPN, nDPN, and HC. The proximal FA was lowest in DPN (DPN 0.37 ± 0.06; nDPN 0.47 ± 0.03; HC 0.49 ± 0.06; P < 0.01). In addition, distal FA was lowest in DPN (DPN 0.31 ± 0.05; nDPN 0.41 ± 0.07; HC 0.43 ± 0.08; P < 0.01). Likewise, proximal ADC was highest in DPN (DPN 1.69 ± 0.25 × 10−3mm2/s; nDPN 1.50 ± 0.06 × 10−3mm2/s; HC 1.42 ± 0.12 × 10−3mm2/s; P < 0.01) as was distal ADC (DPN 1.87 ± 0.45 × 10−3mm2/s; nDPN 1.59 ± 0.19 × 10−3mm2/s; HC 1.57 ± 0.26 × 10−3mm2/s; P = 0.09). The combined interclass‐correlation (ICC) coefficient of DTI reproducibility and repeatability was high in the sciatic nerve (ICC: FA = 0.86; ADC = 0.85) and the tibial nerve (ICC: FA = 0.78; ADC = 0.66). T2‐relaxometry and proton‐spin‐density did not enable detection of neuropathy.

Conclusion

DTI‐MRN accurately detects DPN by lower nerve FA and higher ADC. These alterations are likely to reflect proximal and distal nerve fiber pathology.

Level of Evidence: 1

J. Magn. Reson. Imaging 2017;45:1125–1134
Aligned Poly(ε‐caprolactone) Nanofibers Guide the Orientation and Migration of Human Pluripotent Stem Cell‐Derived Neurons, Astrocytes, and Oligodendrocyte Precursor Cells In Vitro
Authors: Hyysalo Anu , Ristola Mervi , Joki Tiina , Honkanen Mari , Vippola Minnamari , Narkilahti Susanna
Published: March 2017

Stem cell transplantations for spinal cord injury (SCI) have been studied extensively for the past decade in order to replace the damaged tissue with human pluripotent stem cell (hPSC)‐derived neural cells. Transplanted cells may, however, benefit from supporting and guiding structures or scaffolds in order to remain viable and integrate into the host tissue. Biomaterials can be used as supporting scaffolds, as they mimic the characteristics of the natural cellular environment. In this study, hPSC‐derived neurons, astrocytes, and oligodendrocyte precursor cells (OPCs) are cultured on aligned poly(ε‐caprolactone) nanofiber platforms, which guide cell orientation to resemble that of spinal cord in vivo. All cell types are shown to efficiently spread over the nanofiber platform and orient according to the fiber alignment. Human neurons and astrocytes require extracellular matrix molecule coating for the nanofibers, but OPCs grow on nanofibers without additional treatment. Furthermore, the nanofiber platform is combined with a 3D hydrogel scaffold with controlled thickness, and nanofiber‐mediated orientation of hPSC‐derived neurons is also demonstrated in a 3D environment. In this work, clinically relevant materials and substrates for nanofibers, fiber coatings, and hydrogel scaffolds are used and combined with cells suitable for developing functional cell grafts for SCI repair.

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Synthesis of Activated Ester Functional Polyesters through Light‐Induced [4+4] Cycloaddition Polymerization
Authors: Baysak Elif , Durmaz Hakan , Tunca Umit , Hizal Gurkan
Published: March 2017

A combination of light‐induced [4+4] cycloaddition polymerization and activated ester substitution reaction is demonstrated as a new method to obtain novel polymeric structures. Bis‐anthracene functionalized compound involving perfluorophenyl ester moiety namely, bisanthracenyl‐PFPE, is prepared by an esterification reaction, then polymerized under UV light irradiated at 365 nm. The resulting polymer is reacted with a variety of amine compounds namely allylamine, benzylamine, furfurylamine, and propargylamine, under mild conditions. Quantitative conversions of perfluorophenyl ester groups into the respective amide groups as well as the thermal behaviors of all polymers are revealed by using various spectroscopic measurements such as Fourier transform infrared spectroscopy (FT‐IR), gel permeation chromatography, NMR, and differential scanning calorimetry.

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Cross‐Linking Dynamics of Cellulose Nanofibrils‐Based Transient Network Hydrogels: A Study of pH Dependence
Authors: Yin Aishu , Yang Jun
Published: March 2017

Interactions between polymer chains and nanoparticles can play a dominant role in composites mechanics, yet the control of such interfacial dynamics is still a significant challenge. This paper reports the effect of pH on cellulose nanofibrils (CNFs) transient hydrogels network mechanics via interfacial ionic cross‐linking bonds. For this purpose, carboxylated CNFs are incorporated with amine groups terminated 8‐arm poly(ethylene glycol) (PEG‐NH2) to assemble the first noncovalent network via reversible ionic interactions at the CNF surfaces, where the end‐group acrylate modified linear difunctional PEG forms the second lightly covalent cross‐linked network. The viscoelastic properties of the supramolecular gels are examined as a function of pH, and the unique transient mechanics resulting from CNF‐PEG complexation structures show that the processing from acidic‐to‐alkaline pH change leads to the gel cross‐links transition from covalent type to covalent–noncovalent hybrid one. This finding offers an alternative way to tune CNF gels mechanical reinforcement and sheds light on the pH dependence of network architectural changes.

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Nitric oxide‐enhanced Shiga toxin production was regulated by Fur and RecA in enterohemorrhagic Escherichia coli O157
Authors: Ichimura Kimitoshi , Shimizu Takeshi , Matsumoto Akio , Hirai Shinichiro , Yokoyama Eiji , Takeuchi Hiroki , Yahiro Kinnosuke , Noda Masatoshi
Published: March 2017

Enterohemorrhagic Escherichia coli (EHEC) produces Shiga toxin 1 (Stx1) and Shiga toxin 2 (Stx2). Nitric oxide (NO), which acts as an antimicrobial defense molecule, was found to enhance the production of Stx1 and Stx2 in EHEC under anaerobic conditions. Although EHEC O157 has two types of anaerobic NO reductase genes, an intact norV and a deleted norV, in the deleted norV‐type EHEC, a high concentration of NO (12–29 μmol/L, maximum steady‐state concentration) is required for enhanced Stx1 production and a low concentration of NO (~12 μmol/L, maximum steady‐state concentration) is sufficient for enhanced Stx2 production under anaerobic conditions. These results suggested that different concentration thresholds of NO elicit a discrete set of Stx1 and Stx2 production pathways. Moreover, the enhancement of Shiga toxin production in the intact norV‐type EHEC required treatment with a higher concentration of NO than was required for enhancement of Shiga toxin production in the deleted norV‐type EHEC, suggesting that the specific NorV type plays an important role in the level of enhancement of Shiga toxin production in response to NO. Finally, Fur derepression and RecA activation in EHEC were shown to participate in the NO‐enhanced Stx1 and Stx2 production, respectively.
Morphology regulation, structural, and photocatalytic properties of ZnO hierarchical microstructures synthesized by a simple hydrothermal method
Authors: Wang Chunyu , Gao Yindi , Wang Lei , Li Ping
Published: March 2017

Zinc Oxide (ZnO) hierarchical microstructures with diverse morphologies were prepared through a simple one‐step hydrothermal method with zinc chloride and sodium hydroxide as source materials, and citric acid as the modifying agent. The structure and morphology of the samples were studied through X‐ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller specific surface area determination. The morphology of the samples was easily regulated by changing the concentration of citric acid. Branchy structures, porous flowers, porous microspheres, solid flowers, solid flower spheres, and solid spheres of ZnO were obtained. The porous structures obtained with 150–200 mmol · L−1 citric acid showed excellent photocatalytic activities for the degradation of methylene blue under UV irradiation. A possible regulation mechanism of citric acid in ZnO crystals was proposed based on the experimental results.
Assembly and Transport of Microscopic Cargos via Reconfigurable Photoactivated Magnetic Microdockers
Authors: Martinez‐Pedrero Fernando , Massana‐Cid Helena , Tierno Pietro
Published: March 2017

The realization of micromotors able to dock and transport microscopic objects in a fluid medium has direct applications toward the delivery of drugs and chemicals in small channels and pores, and the realization of functional wireless microrobots in lab‐on‐a‐chip technology. A simple and general method to tow microscopic particles in water by using remotely controllable light‐activated hematite microdockers is demonstrated. These anisotropic ferromagnetic particles can be synthesized in bulk and present the remarkable ability to be activated by light while independently manipulated via external fields. The photoactivation process induces a phoretic flow capable to attract cargos toward the surface of the propellers, while a rotating magnetic field is used to transport the composite particles to any location of the experimental platform. The method allows the assembling of small colloidal clusters of various sizes, composed by a skeleton of mobile magnetic dockers, which cooperatively keep, transport, and release the microscopic cargos. The possibility to easily reconfigure in situ the location of the docker above the cargo is demonstrated, which enables optimize transport and cargo release operations.
Monolithic and Flexible ZnS/SnO2 Ultraviolet Photodetectors with Lateral Graphene Electrodes
Authors: Zhang Cheng , Xie Yunchao , Deng Heng , Tumlin Travis , Zhang Chi , Su Jheng‐Wun , Yu Ping , Lin Jian
Published: March 2017

A continuing trend of miniaturized and flexible electronics/optoelectronic calls for novel device architectures made by compatible fabrication techniques. However, traditional layer‐to‐layer structures cannot satisfy such a need. Herein, a novel monolithic optoelectronic device fabricated by a mask‐free laser direct writing method is demonstrated in which in situ laser induced graphene‐like materials are employed as lateral electrodes for flexible ZnS/SnO2 ultraviolet photodetectors. Specifically, a ZnS/SnO2 thin film comprised of heterogeneous ZnS/SnO2 nanoparticles is first coated on polyimide (PI) sheets by a solution process. Then, CO2 laser irradiation ablates designed areas of the ZnS/SnO2 thin film and converts the underneath PI into highly conductive graphene as the lateral electrodes for the monolithic photodetectors. This in situ growth method provides good interfaces between the graphene electrodes and the semiconducting ZnS/SnO2 resulting in high optoelectronic performance. The lateral electrode structure reduces total thickness of the devices, thus minimizing the strain and improving flexibility of the photodetectors. The demonstrated lithography‐free monolithic fabrication is a simple and cost‐effective method, showing a great potential for developement into roll‐to‐roll manufacturing of flexible electronics.
Optimized Metallization for Interdigitated Back Contact Silicon Heterojunction Solar Cells
Authors: Stang Johann‐Christoph , Franssen Thijs , Haschke Jan , Mews Mathias , Merkle Agnes , Peibst Robby , Rech Bernd , Korte Lars
Published: March 2017

We report on the design and manufacturing of interdigitated back contact cells based on the silicon heterojunction technology. The influence of geometry and overlap of the doped amorphous silicon layers forming the contact fingers on device performance have been investigated by simulation. Two contact formation concepts, with and without a TCO interlayer – an indium tin oxide/silver (ITO/Ag) stack, and a direct aluminum (Al) metallization – are experimentally evaluated. The former retains good passivation but leads to a too high contact resistivity, the latter shows the opposite behavior, but yields a slight benefit in terms of overall performance achieving more than 20% of efficiency. We show that in this case a contact system is formed whose properties can be tuned by annealing, enabling a trade‐off between VOC and FF.

Structure of the presented solar cell; a SiNX layer covers the front side, the rear side is passivated by overlapping layer stacks of intrinsic and doped amorphous silicon, the latter are contacted by aluminum.
Sauropod tooth morphotypes from the Upper Jurassic of the Lusitanian Basin (Portugal)
Authors: Mocho Pedro , Royo‐Torres Rafael , Malafaia Elisabete , Escaso Fernando , Ortega Francisco
Published: March 2017

The Upper Jurassic of the Lusitanian Basin has yielded an important fossil record of sauropods, but little information is available about the tooth morphotypes represented in this region. A large sample of teeth, both unpublished and published, is described and discussed here. Four main tooth morphologies are identified: spatulate, heart‐shaped, pencil‐shaped, and compressed cone‐chisel‐shaped. Heart‐shaped teeth are considered to be exclusive to a non‐neosauropod eusauropod, tentatively referred to Turiasauria. The spatulate teeth can be attributed to members of the Macronaria; they have a complex cingulum, more than one lingual facet and a labial ridge. The compressed cone‐chisel‐shaped teeth are also attributed to macronarians and the presence of an axially twisted apex through an arc of 30°–45° suggests putative affinities withEuropasaurusand basal titanosauriforms. The variability observed in the overall morphology and wrinkling pattern of the compressed cone‐chisel‐shaped teeth may be due to factors related to the tooth position or to the ontogeny of individuals. Finally, pencil‐shaped teeth with high slenderness index values, oval and apically located wear facets, subcylindrical crowns and lacking carinae, are tentatively assigned to Diplodocoidea. The diversity of tooth morphologies is in accordance with the known palaeobiodiversity of the Portuguese Late Jurassic sauropod fauna, which is composed of non‐neosauropod eusauropods (turiasaurs), diplodocoids (diplodocids) and macronarians (camarasaurids and probably brachiosaurids). The Late Jurassic sauropod fossil record of the Iberian Peninsula presents the broadest tooth morphospace range in the world from this period, suggesting a wide niche partition for sauropods, and corresponding high taxonomic diversity.
Effects of Refractory and Ladle Glaze on Evolution of Non‐Metallic Inclusions in Al‐Killed Steel
Authors: Chi Yun Guang , Deng Zhi Yin , Zhu Miao Yong
Published: March 2017

Laboratory experiments are carried out to study the effects of different refractories (Al2O3 refractory, MgO refractory, and glazed Al2O3 refractory) on the formation of spinel inclusions and calcium aluminate inclusions. The results show that Al2O3 refractory has almost no influence on the inclusions in Al‐killed steel, while MgO refractory and glazed Al2O3 refractory can help the formation of spinel inclusions from alumina inclusions. Meanwhile, glazed Al2O3 refractory can also contribute to the transformation of spinel inclusions into calcium aluminate inclusions. In contrast to ladle glaze, MgO refractory could supply more dissolved Mg to liquid steel. The formation of dissolved Mg and Ca holds the key for the evolution sequence of alumina, and spinel inclusions form earlier than calcium aluminate inclusions due to the faster formation of dissolved Mg. Besides, ladle glaze can also be a source of calcium aluminate inclusions.
Robust quantile regression using a generalized class of skewed distributions
Authors: Galarza Morales Christian , Lachos Davila Victor , Barbosa Cabral Celso , Castro Cepero Luis
Published: March 2017

It is well known that the widely popular mean regression model could be inadequate if the probability distribution of the observed responses do not follow a symmetric distribution. To deal with this situation, the quantile regression turns to be a more robust alternative for accommodating outliers and the misspecification of the error distribution because it characterizes the entire conditional distribution of the outcome variable. This paper presents a likelihood‐based approach for the estimation of the regression quantiles based on a new family of skewed distributions. This family includes the skewed version of normal, Student‐t, Laplace, contaminated normal and slash distribution, all with the zero quantile property for the error term and with a convenient and novel stochastic representation that facilitates the implementation of the expectation–maximization algorithm for maximum likelihood estimation of the pth quantile regression parameters. We evaluate the performance of the proposed expectation–maximization algorithm and the asymptotic properties of the maximum likelihood estimates through empirical experiments and application to a real‐life dataset. The algorithm is implemented in the R package lqr, providing full estimation and inference for the parameters as well as simulation envelope plots useful for assessing the goodness of fit. Copyright © 2017 John Wiley & Sons, Ltd.
A Population‐Based Cohort Study of Emergency Appendectomy Performed in England and New York State
Authors: Al‐Khyatt Waleed , Mytton Jemma , Tan Benjamin H. L. , Aquina Christopher T. , Evison Felicity , Fleming Fergal J. , Pasquali Sandro , Griffiths Ewen A. , Vohra Ravinder S.
Published: March 2017

Background

To compare selected outcomes (30‐day reoperation and total length of hospital stay) following emergency appendectomy between populations from New York State and England.

Methods

This retrospective cohort study used demographic and in‐hospital outcome data from Hospital Episode Statistics (HES) and the New York Statewide Planning and Research Cooperative System (SPARCS) administrative databases for all patients aged 18+ years undergoing appendectomy between April 2009 and March 2014. Univariate and adjusted multivariable logistic regression were used to test significant factors. A one‐to‐one propensity score matched dataset was created to compare odd ratios (OR) of reoperations between the two populations.

Results

A total of 188,418 patient records, 121,428 (64.4%) from England and 66,990 (35.6%) from NYS, were extracted. Appendectomy was completed laparoscopically in 77.7% of patients in New York State compared to 53.6% in England (P < 0.001). The median lengths of hospital stay for patients undergoing appendectomy were 3 (interquartile range, IQR 2–4) days versus 2 (IQR 1–3) days (P < 0.001) in England and New York State, respectively. All 30‐day reoperation rates were higher in England compared to New York State (1.2 vs. 0.6%, P < 0.001), representing nearly a twofold higher risk of 30‐day reoperation (OR 1.88, 95% CI 1.64–2.14, P < 0.001). As the proportion of appendectomy completed laparoscopically increased, there was a reduction in the reoperation rate in England (correlation coefficient −0.170, P = 0.036).

Conclusions

Reoperations and total length of hospital stay is significantly higher following appendectomy in England compared to New York State. Increasing the numbers of appendectomy completed laparoscopically may decrease length of stay and reoperations.
Neurocognitive function in clinically stable individuals with long‐term bipolar I disorder: Comparisons with schizophrenia patients and controls
Authors: Lin Pei‐Yun , Wang Peng‐Wei , Chen Cheng‐Sheng , Yen Cheng‐Fang
Published: March 2017

This study compared the levels of the five domains of neurocognitive function—executive function, attention, memory, verbal comprehension, and perceptual organization—among clinically stable individuals with long‐term bipolar I disorder, individuals with long‐term schizophrenia, and a group of controls. We recruited a total of 93 clinically stable individuals with bipolar I disorder, 94 individuals with schizophrenia, and 106 controls in this study. Their neurocognitive function was measured using a series of neurocognitive function tests: the Wechsler Adult Intelligence Scale—Third Edition (WAIS‐III), Line Cancellation Test, Visual Form Discrimination, Controlled Oral Word Association Test, Wisconsin Card Sorting Test, Continuous Performance Task, and Wechsler Memory Scale—Third Edition. Neurocognitive function was compared among the three groups through a multivariate analysis of variance. The results indicated that when the effect of age was controlled, clinically stable individuals with bipolar I disorder and those with schizophrenia demonstrated poor neurocognitive function on all tests except for the WAIS‐III Similarity and Information and the Line Cancellation Test. The individuals with bipolar I disorder had similar levels of neurocognitive function compared with the schizophrenia group, but higher levels of neurocognitive function on the WAIS‐III Comprehension, Controlled Oral Word Association Test, and Wechsler Memory Scale—Third Edition Auditory Immediate and Delayed Index and Visual Immediate and Delayed Index. The conclusions of this study suggest that compared with controls, individuals with long‐term bipolar I disorder and those with long‐term schizophrenia have poorer neurocognitive function, even when clinically stable. Individuals with long‐term bipolar I disorder and those with long‐term schizophrenia have similar levels of deficits in several domains of neurocognitive function.
La référence temporelle au futur dans les bulletins météo en France et au Québec : regard variationniste sur l'oral préparé
Authors: Blondeau Hélène , Labeau Emmanuelle
Published: March 2017

La distribution des variables utilisées pour l'expression de l'ultériorité a fait l'objet de nombreuses études, centrées sur l'oral conversationnel ou sur l’écrit. Cet article apporte un éclairage inédit sur la question en considérant les marqueurs du futur dans un contexte communicatif d'oral préparé (le bulletin météo télévisé), et dans une optique diatopique (comparaison d'un corpus français et d'un corpus québécois). L'analyse distributionnelle indique une distribution des variables spécifique au contexte discursif. Par ailleurs, l'analyse multivariée par Goldvarb X révèle une variation diatopique et l'influence de certains facteurs linguistiques, en particulier celui du type de verbe, de même que des contraintes particulières pour les deux communautés étudiées.