bluuebunny/crossref_metadata_2025 huggingface dataset:
Chiro‐Spintronics: Spin‐Dependent Electrochemistry and Water Splitting Using Chiral Molecular Films
Authors: Mondal Prakash Chandra , Mtangi Wilbert , Fontanesi Claudio
Published: February 2018

Molecular spintronics or spin‐based electronics, which utilizes both the spin degrees of freedom and electron charge, has become a hot topic in modern science. Since the introduction of spintronics in 1988, many efforts have been devoted to controlling spin‐polarized current using an external magnetic field, leading to the implementation of commercial solid‐state devices based on the giant magnetoresistance effect. In molecular spintronics, much progress has been achieved with organic molecules, but the role played by chiral molecules is yet to be explored in detail, while it promises to play a role in the future. It has been proved that the interaction of electrons with chiral molecules is spin specific, as supported by several experimental tools, and by theoretical studies. This effect is named “chiral‐induced spin selectivity” (CISS). CISS is based on the fact that chiral molecules exhibit spin‐specific transport properties, and hence can be used as a substitute for ferromagnetic materials. Here, recent spin‐dependent electrochemistry results are highlighted, where chiral molecules are immobilized on a ferromagnetic electrode. Practical applications of the CISS effect, for spin control of charge transport in complex molecular architectures, and in the water‐splitting process are also reviewed.
Nanostructured star‐shaped polythiophene dendrimer as a highly efficient sorbent for microextraction in packed syringe for HPLC analysis of the Clofentezine in milk and juice samples
Authors: Abolghasemi Mir Mahdi , Taheri Hoda , Jaymand Mehdi , Piryaei Marzieh
Published: February 2018

A nanostructured star‐shaped polythiophene dendrimer was prepared and used as an extraction medium for microextraction in packed syringe for clofentezine pesticide in milk and juice samples in combination with high‐performance liquid chromatography. The thermal behaviors, optical properties, and morphologies of the synthesized samples were investigated by thermogravimetric analysis, ultraviolet–visible spectroscopy and field‐emission scanning electron microscopy, respectively. A one‐at‐a‐time strategy was applied for optimizing the important extraction parameters such as the nature of desorption solvent, elution volume, pH, number of extraction cycles and sample volume. Under the optimized conditions, a detection limit of 2 × 10−4 μg mL−1 and a linear calibration curve with an R2 of 0.9983 were obtained for clofentezine. The average recovery of the analyte for juice and milk samples were 97.6 and 93% with relative standard deviation of 3.92 and 2.76%, respectively, for five replicates. The method was successfully applied to the high‐performance liquid chromatography determination of clofentezine in milk and juice samples.
Cross‐border expansion and competitive interactions of indigenous mobile network operators in sub‐Saharan Africa
Authors: Dike Marcellinus C. , Rose Elizabeth L.
Published: February 2018

Emerging‐market multinational enterprises (EMNEs) have become major players in the global economy, with an increasing share of global foreign direct investment (FDI). Indigenous mobile network operators (MNOs) in sub‐Saharan Africa (SSA) are not left out in this pursuit, as they seek growth and competitiveness beyond their domestic markets. We investigate the FDI location choices and competitive interactions of the five indigenous SSA MNOs that had internationalized as of 2014 and find that, contrary to the literature, these EMNEs, operating in a key and rapidly developing industry, did not tend to commence their cross‐border expansion in geographically close markets. In addition, the MNOs are more likely to invest in countries with stronger control over corruption and do not appear to engage in heavy head‐to‐head competition with their rivals. These findings contribute to the internationalization literature in the context of the investment and competitive behaviors of the currently underexplored indigenous SSA multinationals.
Ensemble learning: A survey
Authors: Sagi Omer , Rokach Lior
Published: February 2018

Ensemble methods are considered the state‐of‐the art solution for many machine learning challenges. Such methods improve the predictive performance of a single model by training multiple models and combining their predictions. This paper introduce the concept of ensemble learning, reviews traditional, novel and state‐of‐the‐art ensemble methods and discusses current challenges and trends in the field.

This article is categorized under:

Algorithmic Development > Ensemble Methods

Technologies > Machine Learning

Technologies > Classification
Percutaneous Laser Ablation of Unifocal Papillary Thyroid Microcarcinoma: Utility of Conventional Ultrasound and Contrast‐Enhanced Ultrasound in Assessing Local Therapeutic Response
Authors: Zhang Lu , Zhou Wei , Zhan Weiwei , Peng Yan , Jiang Shan , Xu Shangyan
Published: February 2018

Purpose

To investigate the use of conventional ultrasound and contrast‐enhanced ultrasound (CEUS) in assessing local therapeutic response of percutaneous laser ablation (PLA) for papillary thyroid microcarcinoma (PTMC).

Methods

Sixty‐four patients with 64 PTMCs who were referred to our hospital from November 2013 to July 2016 were treated with PLA. The extent of ablation was assessed by CEUS at 10–20 min and 7 days after PLA. The size and volume of the ablation zone were evaluated on conventional ultrasound at 1 h, 1, 3, 6 and 12 months, and every half‐year thereafter, and recurrences were also recorded. Ultrasound‐guided fine needle aspiration biopsy (FNAB) of the ablated area was performed at 1, 6 and 12 months after PLA.

Results

Two incomplete ablations were detected by CEUS, and a second ablation was performed. The mean largest diameter and volume of the ablated area on CEUS at 10–20 min and 7 days after PLA were significantly larger than those of pre‐treatment on conventional ultrasound (p < 0.05, for both). At the last follow‐up, the mean largest diameter was reduced from 4.6 ± 1.5 to 0.6 ± 1.3 mm (p < 0.0.5), and the average volume was 41.0 ± 40.4 mm3, which decreased to 1.8 ± 6.7 mm3 (p < 0.0.5). A cervical metastatic lymph node was detected on ultrasound and confirmed by ultrasound‐guided FNAB at 30 months after PLA.

Conclusions

CEUS could play a crucial role in assessing the completeness of PLA for treating PTMC, and conventional ultrasound can not only guide the FNAB process but also is important in the follow‐up of PTMC after PLA.
In‐hospital direct costs for thromboembolism and bleeding in Chinese patients with atrial fibrillation
Authors: Chang San‐Shuai , Wu Jia‐Hui , Liu Yi , Zhang Ting , Du Xin , Dong Jian‐Zeng , Lip Gregory Y.H. , Ma Chang‐Sheng
Published: February 2018

Objective

Limited data are available on the direct costs of hospitalization owing to thromboembolism and bleeding in patients with atrial fibrillation (AF) in China. Such data are essential for policy development, service planning, and cost‐effectiveness analysis of new therapeutic strategies. This study aimed to provide detailed data regarding in‐hospital direct costs for these patients, compare the costs at different scenarios, and identify independent factors that may predict the costs.

Methods

We collected data regarding in‐hospital direct costs among patients with AF who were hospitalized owing to ischemic stroke (IS), transient ischemic attack (TIA), intracranial hemorrhage (ICH), or major gastrointestinal bleeding. All data were collected from 7 representative tertiary referral hospitals and 3 secondary care hospitals from December 2009 to October 2014.

Results

In total, 312 eligible patients with thromboembolism and 143 patients with major bleeding were identified, and their hospital charts were reviewed. The median in‐hospital direct costs were 17,857 Chinese Yuan (CNY) for IS and 16,589 CNY for TIA (equivalent to 2907 US dollars and 2701 US dollars, respectively). For patients with major bleeding, the costs were 27,924 CNY for ICH and 18,196 CNY for major gastrointestinal bleeding (equivalent to 4546 US dollars and 2962 US dollars, respectively). The direct costs were mainly driven by medications, which accounted for approximately 33.4%–36.1% in different groups of patients. The direct costs were highly related to the hospital level and National Institutes of Health Stroke Scale scores in patients with thromboembolism; in patients with ICH, the factors included hospital level, warfarin treatment before admission, and prior hospitalization for stroke.

Conclusions

Given the high prevalence, AF‐related thromboembolism and bleeding impose considerable economic burden on the Chinese society. Efforts to improve the management of AF may confer substantial economic benefits.
Use of bone densitometry to assess bone disease in aluminum toxicity complicating parentral nutrition
Authors: Al Awadhi Haifa , Al Mehaidib Ali , Al Dekhail Wajeeh , Mulia Hamdy , Al Saleem Khalid , Abanemai Mohammed
Published: February 2018

Aluminum toxicity affecting bone mineral density is a known complication of long-term parentral nutrition. In this report, we describe a similar patient who suffered from bone disease and had a favorable response to chelation therapy using deferoxamine. We believe this may be a possible agent improving the life quality for the above mentioned group of patients.
Burau Maps and Twisted Alexander Polynomials
Authors: Conway Anthony
Published: February 2018

The Burau representation of the braid group can be used to recover the Alexander polynomial of the closure of a braid. We define twisted Burau maps and use them to compute twisted Alexander polynomials.
On Warm and Cold Baths in the Treatment of Insanity.
Authors: Tuke Harrington
Published: February 2018

I wish it were possible to state, that all the French physicians are as judicious and humane in their prescription of the douche bath, as M. Leuret appears to be, but they certainly order it too frequently as a means of compelling their patients to work, or with the hope and intention of producing a moral effect, which forcibly remind us of the attempt to wash the black man white, of our early fables. In England the douche would not be recognised as a part of ‘moral treatment.’ We are at the present day agreed in thinking that intimidation and coercion may make or modify the symptoms of insanity, but can seldom produce permanently good effects; and I think the douche bath is rightly considered to be legitimately employed only for its physical effect as a revulsive, a refrigerant, or a stimulant. There is one other effect of the douche bath, the ‘shock’ for which it is still sometimes ordered; but I think it a remedy of very questionable utility. I have never tried its efficacy, or seen its effects, but a very well known and esteemed physician states decidedly, that the “physical shock” has been known to produce a good moral impression; and although it is doubtful whether he intends by the expression “physical shock,” the meaning that his words may be taken to convey, they lead us to the consideration of the direct effect of the “shock” upon the nervous system, and the probability of its curative power in cases of its derangement. Dr. Copland in his marvellous work, just completed, the “Medical Dictionary,” thus describes the effect of a sudden douche: “When the stream is considerable, and falls from any height upon the head, its action on the nervous system is often very remarkable, and approaches more nearly than any phenomenon with which I am acquainted, to electro-motive or galvanic agency.
On Irregularity of the Pupils from Central Causes, being the substance of a Paper communicated to the Psychiatrical Section of the Philosophical Association of Germany
Authors: Reicharz  , Palmer Edward
Published: February 2018

la describing the relative sizes of unequal pupils in the diseases of the central organ of the nervous system (as in incomplete general paralysis) most observers make special mention of the dilated pupil, and, under precisely similar essential conditions, we more frequently find one pupil characterised as being larger than the other, than the converse. Were there no prejudice at the bottom of this custom, there might be nothing to advance against it; but I believe that the views on which it is founded, are, more or less, conjectural. It is apparently assumed, in the first place, that inequality of the pupils is always caused by lesion of one iris only; that dilatation of the pupil is more truly and more frequently a morbid condition, than contraction; and, finally, that dilatation is always dependent on relaxation, resulting from paralysis. The iris, with the dilatated pupil is, thus, more often pointed out as being affected, and that with paralysis, than the one in which the pupil is contracted; and we find, moreover, that it is quite usual to adduce, not perhaps, mere inequality, but dilatation of the pupils generally, as an absolute sign and example of paralysis of single muscles.
Overexpression of MicroRNA-29b Decreases Expression of DNA Methyltransferases and Improves Quality of the Blastocysts Derived from Somatic Cell Nuclear Transfer in Cattle
Authors: Liang Shuang , Nie Zheng-Wen , Guo Jing , Niu Ying-Jie , Shin Kyung-Tae , Ock Sun A. , Cui Xiang-Shun
Published: February 2018

MicroRNA (miR)-29b plays a crucial role during somatic cell reprogramming. The aim of the current study was to explore the effects of miR-29b on the developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos, as well as the underlying mechanisms of action. The expression level of miR-29b was lower in bovine SCNT embryos at the pronuclear, 8-cell, and blastocyst stages compared within vitrofertilized embryos. In addition, miR-29b regulates the expression of DNA methyltransferases (Dnmt3a/3bandDnmt1) in bovine SCNT embryos. We further investigated SCNT embryo developmental competence and found that miR-29b overexpression during bovine SCNT embryonic development does not improve developmental potency and downregulation inhibits developmental potency. Nevertheless, the quality of bovine SCNT embryos at the blastocyst stage improved significantly. The expression of pluripotency factors and cellular proliferation were significantly higher in blastocysts from the miR-29b overexpression group than the control and downregulation groups. In addition, outgrowth potential in blastocysts after miR-29b overexpression was also significantly greater in the miR-29b overexpression group than in the control and downregulation groups. Taken together, these results demonstrated that miR-29b plays an important role in bovine SCNT embryo development.
Correlating drought conservation practices and drought vulnerability in a tropical agricultural system
Authors: Álvarez-Berríos Nora L. , Soto-Bayó Sandra , Holupchinski Eva , Fain Stephen J. , Gould William A.
Published: February 2018

Recent droughts in Puerto Rico and throughout the Caribbean have emphasized the region's agricultural vulnerability to this hazard and the increasing need for adaptation mechanisms to support sustainable production. In this study, we assessed the geographic extent of agricultural conservation practices incentivized by US Department of Agriculture Natural Resources Conservation Service (NRCS) and evaluated their large-scale contribution to drought adaptability. We identified concentrations of drought-related practices (e.g. cover crops, ponds) applied between 2000 and 2016. Using information from spatial databases and interviews with experts, we assessed the spatial correlation between these practices and areas exposed to drought as identified by the US Drought Monitor. Between 2000 and 2016, Puerto Rico experienced seven drought episodes concentrated around the south, east and southeastern regions. The most profound drought occurred between 2014 and 2016 when the island experienced 80 consecutive weeks of moderate drought, 48 of severe drought and 33 of extreme drought conditions. A total of 44 drought-related conservation practices were applied at 6984 locations throughout 860 km2 of farmlands between 2000 and 2016 through the NRCS-Environmental Quality Incentives Program (EQIP). Practices related to water availability were statistically clustered along the coasts, whereas soil and plant health practices were clustered in the mountainous region. While these concentrations strongly correlated with areas exposed to moderate drought conditions, >80% did not coincide with areas that experienced severe or extreme drought conditions, suggesting that areas highly exposed to drought conditions generally lacked drought preparedness assisted by EQIP. Climate projections indicate an increase in the frequency and intensity of drought events, particularly in the eastern region of Puerto Rico. Our analysis highlighted the need to implement more conservation practices in these areas subject to drought intensification and exposure. Government programs intended to address vulnerabilities and enhance capacity and resilience may not be reaching areas of highest exposure. Recommendations include raising producer awareness of past and future exposure and making programs more accessible to a broader audience.
Optimal barrier strategy for spectrally negative Lévy process discounted by a class of exponential Lévy processes
Authors: Jiang Huanqun
Published: February 2018

In this paper, we extend the optimality of the barrier strategy for the dividend payment problem to the setting that the underlying surplus process is a spectrally negative Lévy process and the discounting factor is an exponential Lévy process. The proof of the main result uses the fluctuation identities of spectrally negative Lévy processes. This extends recent results of Eisenberg for the case where the accumulated interest rate and surplus process are independent Brownian motions with drift.
Drilling into a Future Earthquake
Authors: Branscombe Alexandra
Published: February 2018

Researchers drill into a fault that is anticipated to rupture in coming decades to study fault structure and earthquake physics.
Glucose metabolism and NRF2 coordinate the antioxidant response in melanoma resistant to MAPK inhibitors
Authors: Khamari Raeeka , Trinh Anne , Gabert Pierre Elliott , Corazao-Rozas Paola , Riveros-Cruz Samuel , Balayssac Stephane , Malet-Martino Myriam , Dekiouk Salim , Joncquel Chevalier Curt Marie , Maboudou Patrice , Garçon Guillaume , Ravasi Laura , Guerreschi Pierre , Mortier Laurent , Quesnel Bruno , Marchetti Philippe , Kluza Jerome
Published: February 2018

Targeted therapies as BRAF and MEK inhibitor combination have been approved as first-line treatment for BRAF-mutant melanoma. However, disease progression occurs in most of the patients within few months of therapy. Metabolic adaptations have been described in the context of acquired resistance to BRAF inhibitors (BRAFi). BRAFi-resistant melanomas are characterized by an increase of mitochondrial oxidative phosphorylation and are more prone to cell death induced by mitochondrial-targeting drugs. BRAFi-resistant melanomas also exhibit an enhancement of oxidative stress due to mitochondrial oxygen consumption increase. To understand the mechanisms responsible for survival of BRAFi-resistant melanoma cells in the context of oxidative stress, we have established a preclinical murine model that accurately recapitulates in vivo the acquisition of resistance to MAPK inhibitors including several BRAF or MEK inhibitors alone and in combination. Using mice model and melanoma cell lines generated from mice tumors, we have confirmed that the acquisition of resistance is associated with an increase in mitochondrial oxidative phosphorylation as well as the importance of glutamine metabolism. Moreover, we have demonstrated that BRAFi-resistant melanoma can adapt mitochondrial metabolism to support glucose-derived glutamate synthesis leading to increase in glutathione content. Besides, BRAFi-resistant melanoma exhibits a strong activation of NRF-2 pathway leading to increase in the pentose phosphate pathway, which is involved in the regeneration of reduced glutathione, and to increase in xCT expression, a component of the xc—amino acid transporter essential for the uptake of cystine required for intracellular glutathione synthesis. All these metabolic modifications sustain glutathione level and contribute to the intracellular redox balance to allow survival of BRAFi-resistant melanoma cells.
Sea ice dynamics across the Mid-Pleistocene transition in the Bering Sea
Authors: Detlef H. , Belt S. T. , Sosdian S. M. , Smik L. , Lear C. H. , Hall I. R. , Cabedo-Sanz P. , Husum K. , Kender S.
Published: February 2018

Sea ice and associated feedback mechanisms play an important role for both long- and short-term climate change. Our ability to predict future sea ice extent, however, hinges on a greater understanding of past sea ice dynamics. Here we investigate sea ice changes in the eastern Bering Sea prior to, across, and after the Mid-Pleistocene transition (MPT). The sea ice record, based on the Arctic sea ice biomarker IP25 and related open water proxies from the International Ocean Discovery Program Site U1343, shows a substantial increase in sea ice extent across the MPT. The occurrence of late-glacial/deglacial sea ice maxima are consistent with sea ice/land ice hysteresis and land−glacier retreat via the temperature−precipitation feedback. We also identify interactions of sea ice with phytoplankton growth and ocean circulation patterns, which have important implications for glacial North Pacific Intermediate Water formation and potentially North Pacific abyssal carbon storage.
Microhomology-assisted scarless genome editing in human iPSCs
Authors: Kim Shin-Il , Matsumoto Tomoko , Kagawa Harunobu , Nakamura Michiko , Hirohata Ryoko , Ueno Ayano , Ohishi Maki , Sakuma Tetsushi , Soga Tomoyoshi , Yamamoto Takashi , Woltjen Knut
Published: February 2018

Gene-edited induced pluripotent stem cells (iPSCs) provide relevant isogenic human disease models in patient-specific or healthy genetic backgrounds. Towards this end, gene targeting using antibiotic selection along with engineered point mutations remains a reliable method to enrich edited cells. Nevertheless, integrated selection markers obstruct scarless transgene-free gene editing. Here, we present a method for scarless selection marker excision using engineered microhomology-mediated end joining (MMEJ). By overlapping the homology arms of standard donor vectors, short tandem microhomologies are generated flanking the selection marker. Unique CRISPR-Cas9 protospacer sequences nested between the selection marker and engineered microhomologies are cleaved after gene targeting, engaging MMEJ and scarless excision. Moreover, when point mutations are positioned unilaterally within engineered microhomologies, both mutant and normal isogenic clones are derived simultaneously. The utility and fidelity of our method is demonstrated in human iPSCs by editing the X-linkedHPRT1locus and biallelic modification of the autosomalAPRTlocus, eliciting disease-relevant metabolic phenotypes.
Operando spectroscopy study of the carbon dioxide electro-reduction by iron species on nitrogen-doped carbon
Authors: Genovese Chiara , Schuster Manfred E. , Gibson Emma K. , Gianolio Diego , Posligua Victor , Grau-Crespo Ricardo , Cibin Giannantonio , Wells Peter P. , Garai Debi , Solokha Vladyslav , Krick Calderon Sandra , Velasco-Velez Juan J. , Ampelli Claudio , Perathoner Siglinda , Held Georg , Centi Gabriele , Arrigo Rosa
Published: February 2018

The carbon–carbon coupling via electrochemical reduction of carbon dioxide represents the biggest challenge for using this route as platform for chemicals synthesis. Here we show that nanostructured iron (III) oxyhydroxide on nitrogen-doped carbon enables high Faraday efficiency (97.4%) and selectivity to acetic acid (61%) at very-low potential (−0.5 V vs silver/silver chloride). Using a combination of electron microscopy, operando X-ray spectroscopy techniques and density functional theory simulations, we correlate the activity to acetic acid at this potential to the formation of nitrogen-coordinated iron (II) sites as single atoms or polyatomic species at the interface between iron oxyhydroxide and the nitrogen-doped carbon. The evolution of hydrogen is correlated to the formation of metallic iron and observed as dominant reaction path over iron oxyhydroxide on oxygen-doped carbon in the overall range of negative potential investigated, whereas over iron oxyhydroxide on nitrogen-doped carbon it becomes important only at more negative potentials.
Author Correction: Low frequency transcranial electrical stimulation does not entrain sleep rhythms measured by human intracranial recordings
Authors: Lafon Belen , Henin Simon , Huang Yu , Friedman Daniel , Melloni Lucia , Thesen Thomas , Doyle Werner , Buzsáki György , Devinsky Orrin , Parra Lucas C. , Liu Anli
Published: February 2018

It has come to our attention that we did not specify whether the stimulation magnitudes we report in this Article are peak amplitudes or peak-to-peak. All references to intensity given in mA in the manuscript refer to peak-to-peak amplitudes, except in Fig. 2, where the model is calibrated to 1 mA peak amplitude, as stated. In the original version of the paper we incorrectly calibrated the computational models to 1 mA peak-to-peak, rather than 1 mA peak amplitude. This means that we divided by a value twice as large as we should have. The correct estimated fields are therefore twice as large as shown in the original Fig. 2 and Supplementary Figure 11. The corrected figures are now properly calibrated to 1 mA peak amplitude. Furthermore, the sentence in the first paragraph of the Results section ‘Intensity ranged from 0.5 to 2.5 mA (current density 0.125–0.625 mA mA/cm2), which is stronger than in previous reports’, should have read ‘Intensity ranged from 0.5 to 2.5 mA peak to peak (peak current density 0.0625–0.3125 mA/cm2), which is stronger than in previous reports.’ These errors do not affect any of the Article’s conclusions.
Genetic profiling of poorly differentiated sinonasal tumours
Authors: López-Hernández Alejandro , Vivanco Blanca , Franchi Alessandro , Bloemena Elisabeth , Cabal Virginia N. , Potes Sira , Riobello Cristina , García-Inclán Cristina , López Fernando , Llorente José L. , Hermsen Mario
Published: February 2018

The sinonasal cavities harbour a variety of rare tumour types. Many carry a poor prognosis while therapeutic options are limited. Histopathological classification can be difficult, especially for poorly differentiated tumours such as olfactory neuroblastoma (ONB), sinonasal neuroendocrine carcinoma (SNEC) and sinonasal undifferentiated carcinoma (SNUC). We analysed Affymetrix OncoScan genome-wide copy number profiles of these three tumour types, both as originally diagnosed and as regrouped by their cytokeratin (Ck) and neuroendocrine (Ne) expression pattern, aiming to find a relation between phenotype and genotype. According to the original histopathological classification our series consisted of 24 ONB, 11 SNEC and 19 SNUC, while immunohistochemistry indicated 11 Ck−Ne+/ONB, 18 Ck+Ne+/SNEC, 24 Ck+Ne−/SNUC, and 1 Ck−Ne−/unclassified. As originally diagnosed, the three tumour types showed similar copy number profiles. However, when regrouped by Ck/Ne immunostaining we found a distinct set of gains and losses; Ck−Ne+/ONB harboured few and predominantly whole chromosomes abnormalities, Ck+Ne+/SNEC carried both gains and losses in high frequency, and Ck+Ne−/SNUC showed mostly gains. In addition, each tumour carried a number of unique chromosomal deletions. Genome-wide copy number profiling supports the value of immunohistochemical CkNe staining of ONB, SNEC and SNUC for tumour classification, which is important for prognosis and therapeutic decision-making.
Phenotype-driven identification of epithelial signalling clusters
Authors: Marques Elsa , Peltola Tomi , Kaski Samuel , Klefström Juha
Published: February 2018

In metazoans, epithelial architecture provides a context that dynamically modulates most if not all epithelial cell responses to intrinsic and extrinsic signals, including growth or survival signalling and transforming oncogene action. Three-dimensional (3D) epithelial culture systems provide tractable models to interrogate the function of human genetic determinants in establishment of context-dependency. We performed an arrayed genetic shRNA screen in mammary epithelial 3D cultures to identify new determinants of epithelial architecture, finding that the key phenotype impacting shRNAs altered not only the data population average but even more noticeably the population distribution. The broad distributions were attributable to sporadic gene silencing actions by shRNA in unselected populations. We employed Maximum Mean Discrepancy concept to capture similar population distribution patterns and demonstrate here the feasibility of the test in identifying an impact of shRNA in populations of 3D structures. Integration of the clustered morphometric data with protein-protein interactions data enabled hypothesis generation of novel biological pathways underlying similar 3D phenotype alterations. The results present a new strategy for 3D phenotype-driven pathway analysis, which is expected to accelerate discovery of context-dependent gene functions in epithelial biology and tumorigenesis.
Voxel-wise comparisons of cellular microstructure and diffusion-MRI in mouse hippocampus using 3D Bridging of Optically-clear histology with Neuroimaging Data (3D-BOND)
Authors: Stolp H. B. , Ball G. , So P.-W. , Tournier J.-D. , Jones M. , Thornton C. , Edwards A. D.
Published: February 2018

A key challenge in medical imaging is determining a precise correspondence between image properties and tissue microstructure. This comparison is hindered by disparate scales and resolutions between medical imaging and histology. We present a new technique, 3D Bridging of Optically-clear histology with Neuroimaging Data (3D-BOND), for registering medical images with 3D histology to overcome these limitations. Ex vivo 120 × 120 × 200 μm resolution diffusion-MRI (dMRI) data was acquired at 7 T from adult C57Bl/6 mouse hippocampus. Tissue was then optically cleared using CLARITY and stained with cellular markers and confocal microscopy used to produce high-resolution images of the 3D-tissue microstructure. For each sample, a dense array of hippocampal landmarks was used to drive registration between upsampled dMRI data and the corresponding confocal images. The cell population in each MRI voxel was determined within hippocampal subregions and compared to MRI-derived metrics. 3D-BOND provided robust voxel-wise, cellular correlates of dMRI data. CA1 pyramidal and dentate gyrus granular layers had significantly different mean diffusivity (p > 0.001), which was related to microstructural features. Overall, mean and radial diffusivity correlated with cell and axon density and fractional anisotropy with astrocyte density, while apparent fibre density correlated negatively with axon density. Astrocytes, axons and blood vessels correlated to tensor orientation.
MSeq-CNV: accurate detection of Copy Number Variation from Sequencing of Multiple samples
Authors: Malekpour Seyed Amir , Pezeshk Hamid , Sadeghi Mehdi
Published: February 2018

Currently a few tools are capable of detecting genome-wide Copy Number Variations (CNVs) based on sequencing of multiple samples. Although aberrations in mate pair insertion sizes provide additional hints for the CNV detection based on multiple samples, the majority of the current tools rely only on the depth of coverage. Here, we propose a new algorithm (MSeq-CNV) which allows detecting common CNVs across multiple samples. MSeq-CNV applies a mixture density for modeling aberrations in depth of coverage and abnormalities in the mate pair insertion sizes. Each component in this mixture density applies a Binomial distribution for modeling the number of mate pairs with aberration in the insertion size and also a Poisson distribution for emitting the read counts, in each genomic position. MSeq-CNV is applied on simulated data and also on real data of six HapMap individuals with high-coverage sequencing, in 1000 Genomes Project. These individuals include a CEU trio of European ancestry and a YRI trio of Nigerian ethnicity. Ancestry of these individuals is studied by clustering the identified CNVs. MSeq-CNV is also applied for detecting CNVs in two samples with low-coverage sequencing in 1000 Genomes Project and six samples form the Simons Genome Diversity Project.
Kinetic effects in thermal explosion with oscillating ambient conditions
Authors: Novozhilov Vasily
Published: February 2018

Thermal explosion problem for a medium with oscillating ambient temperature at its boundaries is a new problem which was introduced in the preceding publication by the present author. It is directly applicable to a range of practical fire autoignition scenarios (e.g. in the storages of organic matter, explosives, propellants, etc.). Effects of kinetic mechanisms, however, need be further investigated as they are expected to alter critical conditions of thermal explosion. We consider several global kinetic mechanisms: first order reaction, second order reaction, and first order autocatalysis. It is demonstrated that kinetic effects related to reactants consumption do indeed shift respective critical boundaries. Effect of kinetics on oscillatory development of thermal explosion is of particular interest. In line with conclusions of the preceding publication, it is confirmed that temperature oscillations may develop during induction phase of thermal explosion when the effect of reactants consumption is properly taken into account. Moreover, development of thermal explosion instability through the prior oscillations is an inevitable and natural scenario. This fact is confirmed by a number of examples. Besides, effects of the other relevant parameter, Zeldovich number on critical conditions are also investigated.
The impact of creating mathematical formula to predict cardiovascular events in patients with heart failure
Authors: Sakamoto Mari , Fukuda Hiroki , Kim Jiyoong , Ide Tomomi , Kinugawa Shintaro , Fukushima Arata , Tsutsui Hiroyuki , Ishii Akira , Ito Shin , Asanuma Hiroshi , Asakura Masanori , Washio Takashi , Kitakaze Masafumi
Published: February 2018

Since our retrospective study has formed a mathematical formula, α = f(x1, …, x252), where α is the probability of cardiovascular events in patients with heart failure (HF) and x1 is each clinical parameter, we prospectively tested the predictive capability and feasibility of the mathematical formula of cardiovascular events in HF patients. First of all, to create such a mathematical formula using limited number of the parameters to predict the cardiovascular events in HF patients, we retrospectively determined f(x) that formulates the relationship between the most influential 50 clinical parameters (x) among 252 parameters using 167 patients hospitalized due to acute HF; the nonlinear optimization could provide the formula of α = f(x1, …, x50) which fitted the probability of the actual cardiovascular events per day. Secondly, we prospectively examined the predictability of f(x) in other 213 patients using 50 clinical parameters in 3 hospitals, and we found that the Kaplan–Meier curves using actual and estimated occurrence probabilities of cardiovascular events were closely correlated. We conclude that we created a mathematical formula f(x) that precisely predicted the occurrence probability of future cardiovascular outcomes of HF patients per day. Mathematical modelling may predict the occurrence probability of cardiovascular events in HF patients.
Omnivore-herbivore interactions: thrips and whiteflies compete via the shared host plant
Authors: Pappas Maria L. , Tavlaki Georgia , Triantafyllou Anneta , Broufas George
Published: February 2018

Phytophagy is a common feature among pure herbivorous insects and omnivores that utilise both plant and prey as food resources; nevertheless, experimental evidence for factors affecting their interactions is restricted to intraguild predation and predator-mediated competition. We herein focused on plant-mediated effects that could result from plant defence activation or quality alteration and compared the performance of an omnivore, the western flower thrips Frankliniella occidentalis, and a pure herbivore, the greenhouse whitefly Trialeurodes vaporariorum, on cucumber plants previously infested with either species. Furthermore, we recorded their behavioural responses when given a choice among infested and clean plants. Whiteflies laid less eggs on plants previously exposed to thrips but more on whitefly-infested plants. Thrips survival was negatively affected on whitefly-infested than on thrips-infested or clean plants. Notably, whiteflies developed significantly faster on plants infested with conspecifics. In accordance, whiteflies avoided thrips-infested plants and preferred whitefly-infested over clean plants. Thrips showed no preference for either infested or clean plants. Our study is a first report on the role of plant-mediated effects in shaping omnivore-herbivore interactions. Considering the factors driving such interactions we will likely better understand the ecology of the more complex relationships among plants and pest organisms.
Three dimensional electron microscopy reveals changing axonal and myelin morphology along normal and partially injured optic nerves
Authors: Giacci Marcus K. , Bartlett Carole A. , Huynh Minh , Kilburn Matt R. , Dunlop Sarah A. , Fitzgerald Melinda
Published: February 2018

Following injury to the central nervous system, axons and myelin distinct from the initial injury site undergo changes associated with compromised function. Quantifying such changes is important to understanding the pathophysiology of neurotrauma; however, most studies to date used 2 dimensional (D) electron microscopy to analyse single sections, thereby failing to capture changes along individual axons. We used serial block face scanning electron microscopy (SBF SEM) to undertake 3D reconstruction of axons and myelin, analysing optic nerves from normal uninjured female rats and following partial optic nerve transection. Measures of axon and myelin dimensions were generated by examining 2D images at 5 µm intervals along the 100 µm segments. In both normal and injured animals, changes in axonal diameter, myelin thickness, fiber diameter, G-ratio and percentage myelin decompaction were apparent along the lengths of axons to varying degrees. The range of values for axon diameter along individual reconstructed axons in 3D was similar to the range from 2D datasets, encompassing reported variation in axonal diameter attributed to retinal ganglion cell diversity. 3D electron microscopy analyses have provided the means to demonstrate substantial variability in ultrastructure along the length of individual axons and to improve understanding of the pathophysiology of neurotrauma.
The effects of oxygen in spinel oxide Li1+xTi2−xO4−δ thin films
Authors: Jia Yanli , He Ge , Hu Wei , Yang Hua , Yang Zhenzhong , Yu Heshan , Zhang Qinghua , Shi Jinan , Lin Zefeng , Yuan Jie , Zhu Beiyi , Gu Lin , Li Hong , Jin Kui
Published: February 2018

The evolution from superconducting LiTi2O4-δ to insulating Li4Ti5O12 thin films has been studied by precisely tuning the oxygen pressure in the sample fabrication process. In superconducting LiTi2O4-δ films, with the increase of oxygen pressure, the oxygen vacancies are filled gradually and the c-axis lattice constant decreases. When the oxygen pressure increases to a certain critical value, the c-axis lattice constant becomes stable, which implies that the sample has been completely converted to Li4Ti5O12 phase. The two processes can be manifested by the angular bright-field images of the scanning transmission electron microscopy techniques. The transition temperature (T
ch
) of magnetoresistance from the positive to the negative shows a nonmonotonic behavior, i.e. first decrease and then increase, with the increase of oxygen pressure. We suggest that the decrease Tch can be attributed to the suppressing of orbital-related state, and the inhomogeneous phase separated regions contribute positive MR and thereby lead to the reverse relation between Tch and oxygen pressure.
The relation between mental health, homosexual stigma, childhood abuse, community engagement, and unprotected anal intercourse among MSM in China
Authors: Zhu Yaxin , Liu Jie , Chen Yucun , Zhang Ruochen , Qu Bo
Published: February 2018

The aim of the study was to explore the relation of various factors with unprotected anal intercourse (UAI) and provide some insight for HIV intervention on Chinese men who have sex with men (MSM). The current cross-sectional study recruited 365 MSM in Dalian, China. More than half of the respondents (117 respondents, 51.8% of the sample) had engaged in UAI. The multivariable logistic regression model suggested that poorer mental health (AOR: 7.16; 95% CI: 3.14–16.31), self-stigma (AOR: 1.53; 95% CI: 1.00–2.34), and experience(s) of physical abuse in childhood (AOR: 5.85; 95% CI: 1.77–19.30) were significantly and positively related to UAI. Community engagement was negatively associated with UAI (p < 0.05). It appears it is necessary to incorporate mental health services, eliminate the stigma against homosexuality, and facilitate MSM-related community engagement into intervention strategies to prevent UAI among Chinese MSM. Targeted UAI interventions in the subgroup with a history of childhood physical abuse should also be of great concern.
Exposure of kale root to NaCl and Na2SeO3 increases isothiocyanate levels and Nrf2 signalling without reducing plant root growth
Authors: Kim Sun Young , Park Jai-Eok , Kim Eun Ok , Lim Sue Ji , Nam Eui Jeong , Yun Ji Ho , Yoo GyHye , Oh Sang-Rok , Kim Hyoung Seok , Nho Chu Won
Published: February 2018

A plant factory is a closed cultivation system that provides a consistent and modified environment for plant growth. We speculated that treatment of kale (Brassica oleracea) grown in a plant factory with NaCl, Na2SeO3, or both would increase the bioactive phytochemical levels including glucosinolates (GLSs) and isothiocyanates (ITCs), the key molecules in cancer prevention. The kale was harvested and analysed after treatment with NaCl and Na2SeO3 alone or in combination for 1 or 2 weeks. Exposure to NaCl alone but not Na2SeO3 increased plant root growth. Levels of sinigrin were increased by a 2-week exposure to Na2SeO3 alone or in combination with NaCl, whereas no changes were observed in glucoraphanin and gluconasturtiin gluconasturtiin levels. Importantly, the ITC concentration was affected by 2-week treatment with both compounds. To evaluate the bioactivity of kale, HepG2 human hepatoma cells were treated with plant extract for 6 h. Only the extract of kale roots exposed to a combination NaCl and Na2SeO3 for 2 weeks showed an increased expression of nuclear factor erythroid 2-related factor (Nrf2), which regulates genes encoding antioxidant proteins. These data suggest that co-treatment with NaCl and Na2SeO3 increased the ITC content and chemopreventive effects of kale root.
Socioeconomic Status and Race are both Independently associated with Increased Hospitalization Rate among Crohn’s Disease Patients
Authors: Walker Caroline , Allamneni Chaitanya , Orr Jordan , Yun Huifeng , Fitzmorris Paul , Xie Fenglong , Malik Talha A.
Published: February 2018

Racial disparities are observed clinically in Crohn’s Disease (CD) with research suggesting African Americans (AA) have worse outcomes than Caucasian Americans (CA). The aim of this study is to assess whether socioeconomic status (SES) rather than race is the major predictor of worse outcomes. We designed a retrospective cohort study of 944 CD patients seen at our center. Patients’ billing zip codes were collected and average income and percent of population living above or below poverty level (PL) for each zip code calculated. Patients were separated by quartiles using average state income level and federal PL. Demographics and hospitalization rates were collected. Poison regression models estimated incidence rate ratios (IRR) for CD-related hospitalizations. Incidence rate (IR) of hospitalization per 100-person years for the lowest income group was 118 (CI 91.4–152.3), highest income group was 29 (CI 21.7–38.9), Above PL was 26.9 (25.9–28.9), Below PL was 35.9 (33.1–38.9), CA was 25.3 (23.7–27), and AA was 51.4 (46.8–56.3). IRR for a CD-related hospitalization for lowest income group was 2.01 (CI 1.34–3.01), for Below PL was 1.26 (CI 1.12–1.42), and for AAs was 1.88 (CI 1.66–2.12). SES and race are both associated with hospitalization among CD patients and need further investigation.
Myocardial Effective Transverse Relaxation Time T 2 * is Elevated in Hypertrophic Cardiomyopathy: A 7.0 T Magnetic Resonance Imaging Study
Authors: Huelnhagen Till , Ku Min-Chi , Reimann Henning Matthias , Serradas Duarte Teresa , Pohlmann Andreas , Flemming Bert , Seeliger Erdmann , Eichhorn Christina , A. Ferrari Victor , Prothmann Marcel , Schulz-Menger Jeanette , Niendorf Thoralf
Published: February 2018

Hypertrophic cardiomyopathy (HCM) is the most common genetic disease of the myocardium and bares the risk of progression to heart failure or sudden cardiac death. Identifying patients at risk remains an unmet need. Recognizing the dependence of microscopic susceptibility on tissue microstructure and on cardiac macromorphology we hypothesized that myocardial T2*might be altered in HCM patients compared to healthy controls. To test this hypothesis, myocardial T2*-mapping was conducted at 7.0 Tesla to enhance T2*-contrast. 2D CINE T2*-mapping was performed in healthy controls and HCM patients. To ensure that T2*is not dominated by macroscopic magnetic field inhomogeneities, volume selective B0shimming was applied. T2*changes in the interventricular septum across the cardiac cycle were analyzed together with left ventricular radius and ventricular septal wall thickness. The results show that myocardial T2*is elevated throughout the cardiac cycle in HCM patients compared to healthy controls. A mean septal T2* = 13.7 ± 1.1 ms (end-systole: T2*,systole = 15.0 ± 2.1, end-diastole: T2*,diastole = 13.4 ± 1.3 ms, T2*,systole/T2*,diastoleratio = 1.12) was observed in healthy controls. For HCM patients a mean septal T2* = 17.4 ± 1.4 ms (end-systole: T2*,systole = 17.7 ± 1.2 ms, end-diastole: T2*,diastole = 16.2 ± 2.5 ms, T2*,systole/T2*,diastoleratio = 1.09) was found. Our preliminary results provide encouragement that assessment of T2*and its changes across the cardiac cycle may benefit myocardial tissue characterization in HCM.
Monosulfonicpillar[5]arene: Synthesis, Characterization, and Complexation with Tetraphenylethene for Aggregation-Induced Emission
Authors: Jin Xiao-Yu , Song Nan , Wang Xu , Wang Chun-Yu , Wang Yan , Yang Ying-Wei
Published: February 2018

A pillar[5]arene derivative with a hydrophilic sulfonic group, i.e., monosulfonicpillar[5]arene (MSP5), has been successfully synthesized for the first time, which exhibited strong binding affinity towards alcohol analogs. Significantly, fluorescent supramolecular ensemble was fabricated from the supramolecular complexation of MSP5 and a neutral guest with tetraphenylethene core. Enhanced fluorescent emission of this system can be detected both in dilute solution and the solid state, and its temperature and competitive guest multi-responsive properties suggest its promising application as a chemical sensor towards alcohol analogs, ethylenediamine, and temperature variations.
Effects of electron-donating groups on the photocatalytic reaction of MOFs
Authors: Li Shixiong , Sun Shengli , Wu Haizhen , Wei Chaohai , Hu Yun
Published: February 2018

Regulating the synthesis of photocatalytic materials at the molecular level could affect the absorption of light and guide the synthesis of highly efficient photocatalysts for the photocatalytic degradation organic pollutants.
Geophysical constraints on the reliability of solar and wind power in the United States
Authors: Shaner Matthew R. , Davis Steven J. , Lewis Nathan S. , Caldeira Ken
Published: February 2018

Daily and seasonal variability of solar, wind and electricity demand require substantial dispatchable power capacity to achieve deep decarbonization with high reliability.