bluuebunny/crossref_metadata_2025 huggingface dataset:
Holoprosencephaly: signaling interactions between the brain and the face, the environment and the genes, and the phenotypic variability in animal models and humans
Authors: Petryk Anna , Graf Daniel , Marcucio Ralph
Published: October 2014

Holoprosencephaly (HPE) is the most common developmental defect of the forebrain characterized by inadequate or absent midline division of the forebrain into cerebral hemispheres, with concomitant midline facial defects in the majority of cases. Understanding the pathogenesis of HPE requires knowledge of the relationship between the developing brain and the facial structures during embryogenesis. A number of signaling pathways control and coordinate the development of the brain and face, including Sonic hedgehog, Bone morphogenetic protein, Fibroblast growth factor, and Nodal signaling. Mutations in these pathways have been identified in animal models of HPE and human patients. Because of incomplete penetrance and variable expressivity of HPE, patients carrying defined mutations may not manifest the disease at all, or have a spectrum of defects. It is currently unknown what drives manifestation of HPE in genetically at‐risk individuals, but it has been speculated that other gene mutations and environmental factors may combine as cumulative insults. HPE can be diagnosed in utero by a high‐resolution prenatal ultrasound or a fetal magnetic resonance imaging, sometimes in combination with molecular testing from chorionic villi or amniotic fluid sampling. Currently, there are no effective preventive methods for HPE. Better understanding of the mechanisms of gene–environment interactions in HPE would provide avenues for such interventions. WIREs Dev Biol 2015, 4:17–32. doi: 10.1002/wdev.161

This article is categorized under:

Nervous System Development > Vertebrates: General Principles

Birth Defects > Craniofacial and Nervous System Anomalies
Successive distinct high‐grade gliomas in L‐2‐hydroxyglutaric aciduria
Authors: Patay Zoltan , Orr Brent A. , Shulkin Barry L. , Hwang Scott N. , Ying Yuan , Broniscer Alberto , Boop Frederick A. , Ellison David W.
Published: October 2014

Patients with L‐2‐hydroxyglutaric aciduria are at risk for developing cerebral neoplasms, particularly gliomas, as one of the optical isomers of the known oncometabolite, 2‐hydroxyglutarate is produced in L‐2‐hydroxyglutaric aciduria. To illustrate the concept of sustained oncogenic potential in permanent exposure to L‐2‐hydroxyglutarate in brain tissue, we present the medical history of a patient with L‐2‐hydroxyglutaric aciduria who underwent surgery to remove a right temporal anaplastic astrocytoma and developed an anatomically distinct, but histopathologically similar, tumor in the left frontal region 40 months later. This is the first reported case of successive distinct gliomas in a patient with L‐2‐hydroxyglutaric aciduria. While this implies a significant, cumulative lifetime risk for cerebral neoplasms in patients with this rare organic aciduria, it also allows further insight into a unique mechanism of tumorigenesis in the brain.
A promising concept of combination therapy for positional obstructive sleep apnea
Authors: Dieltjens Marijke , Vroegop Anneclaire V. , Verbruggen Annelies E. , Wouters Kristien , Willemen Marc , De Backer Wilfried A. , Verbraecken Johan A. , Van de Heyning Paul H. , Braem Marc J. , de Vries Nico , Vanderveken Olivier M.
Published: October 2014

Purpose

The objective of this randomized controlled trial was to assess the additional effect of a chest-worn sleep position trainer (SPT) in patients with residual supine-dependent obstructive sleep apnea (sdOSA) under mandibular advancement device (MAD) therapy.

Methods

Baseline and follow-up polysomnography with MAD were performed. Twenty patients with sdOSA under MAD therapy underwent two consecutive randomized polysomnographies: one with SPT and one with combination of SPT + MAD. Data are presented as median (quartile 1, quartile 3).

Results

The SPT reduced the time spent in supine sleeping position compared to baseline and MAD therapy. Both MAD and SPT were individually effective in reducing the overall apnea/hypopnea index (AHI) significantly when compared to baseline from 20.8 (15.1; 33.6)/h at baseline to 11.0 (6.7; 13.8)/h and to 11.1 (3.5; 17.7)/h with MAD or SPT, respectively. The combination of SPT + MAD further reduced the overall AHI to 5.7 (3.6; 7.4), which was significantly lower than with MAD alone (p < 0.001) and SPT alone (p < 0.008), respectively.

Conclusions

The results of this study indicate that combination of SPT + MAD leads to a higher therapeutic efficacy in patients with sdOSA under MAD therapy when compared to one of the treatment modalities alone.
Prevalence, incidence, and clinical impact of sarcopenia: facts, numbers, and epidemiology—update 2014
Authors: Morley John E. , Anker Stefan D. , von Haehling Stephan
Published: October 2014

Sarcopenia is now defined as a decline in walking speed or grip strength associated with low muscle mass. Sarcopenia leads to loss of mobility and function, falls, and mortality. Sarcopenia is a major cause of frailty, but either condition can occur without the other being present. Sarcopenia is present in about 5 to 10 % of persons over 65 years of age. It has multiple causes including disease, decreased caloric intake, poor blood flow to muscle, mitochondrial dysfunction, a decline in anabolic hormones, and an increase in proinflammatory cytokines. Basic therapy includes resistance exercise and protein and vitamin D supplementation. There is now a simple screening test available for sarcopenia—SARC‐F. All persons 60 years and older should be screened for sarcopenia and treated when appropriate.
Tribological properties of conductive lubricating greases
Authors: Fan Xiaoqiang , Xia Yanqiu , Wang Liping
Published: October 2014

Three kinds of new conductive lubricating greases were prepared using lithium ionic liquids as the base oil and the polytetrafluoroethylene (PTFE) as the thickener. These lithium ionic liquids ([Li(PEG)X]) were obtained by blending lithium salts (LiBF4, LiPF6 and LiNTf2) with poly(ethylene glycol) (PEG) because lithium salts have an extremely high solubility in PEG. The conductivities and contact resistances of the prepared lubricating greases were investigated using the DDSJ-308A conductivity meter and the reciprocating ball-on-disk UMT-2MT sliding tester. In addition, their tribological properties were investigated in detail. Scanning electron microscopy and X-ray photoelectron spectroscopy were employed to explore the friction mechanisms. The results suggest that the prepared lubricating greases have high conductivities and excellent tribological properties. The high conductivities are attributed to ion diffusion or migration of the lithium ionic liquids with an external electric field, and the excellent tribological properties depend on the formation of boundary protective films.
The di‐peptide Trp‐His activates AMP‐activated protein kinase and enhances glucose uptake independently of insulin in L6 myotubes
Authors: Soga Minoru , Ohashi Ayaka , Taniguchi Megumi , Matsui Toshiro , Tsuda Takanori
Published: October 2014

These findings indicate that (1) WH activates AMPK and insulin independently enhances glucose uptake following translocation of Glut4 to the plasma membrane, (2) activation of AMPKα by WH is mediated by the LKB1 pathway, without altering the Ca2+‐dependent pathway, and (3) L6 myotubes express only one type of peptide transporter (PHT1; SLC15a4), which incorporates WH into cells to activate AMPKα.
Replacing nebulizers by MDI-spacers for bronchodilator and inhaled corticosteroid administration
Authors: Alhaider S.A. , Alshehri H.A. , Al-Eid K.
Published: October 2014

Background and objectives:

Metered-dose inhalers plus spacers (MDI-spacer) are as effective as, or better than, nebulizers in aerosol delivery. The selection of aerosol delivery system for hospitalized children can have a significant impact on the utilization of healthcare resources.

Design and setting:

A quality improvement project to evaluate the impact of conversion to MDI-spacer to administer bronchodilators (BDs) and inhaled corticosteroids (ICSs) to hospital-ized children on the utilization of hospital resources. The project was conducted in a tertiary pediatric ward from April to May 2013.

Materials and methods:

The project was conducted over a six-week period. In the first two weeks, data were gathered from all hospitalized children receiving BDs and/or ICSs by nebu-lizers. This data collection was followed by a two-week washout period during which training of healthcare providers and operational changes were implemented to enhance the conversion to MDI-spacer. In the last two weeks, data were gathered from hospitalized children after con-version to MDI-spacer. The primary outcomes included the mean time (in minutes) of medica-tion preparation and delivery. Secondary outcomes included the following: need for respiratory therapy assistance, estimated cost of treatment sessions, and patient/caregiver satisfaction.

Results:

Five hundred seventy-five treatment sessions were enrolled (288 on nebulizers, 287 on MDI-spacer). The nebulizer group had more male predominance and were slightly older compared to the MDI-spacer group (male: 59% vs. 53% and mean age: 52 vs. 40 months respectively). The duration of treatment preparation and delivery was significantly lower in the MDI-spacer group (2 min reduction in preparation time and 5 min reduction in delivery time; p < 0.01). Caregivers mastered MDI-spacer use after an average of two observed ses-sions, eliminating the need for respiratory therapy assistance during the hospital stay. Medica-tion cost analysis showed savings in favor of MDI-spacer (cost reduction per 100 doses: 50% for albuterol, 30% for ipratropium bromide, and 87% for ICSs). The patient satisfaction survey showed "very good” to "excellent” levels in both groups.

Conclusions:

Conversion to MDI-spacer for BDs and ICSs administration in hospitalized children improve hospital resource utilization.
Neonatal molybdenum cofactor deficiency and ectopia lentis in a Saudi Arabian patient
Authors: Al-Obaidalla Meshaal A. , Mbekeani Joyce N. , Dogar Mohammad Asif , Hazzaa Selwa A. Al
Published: October 2014

Molybdenum cofactor deficiency (MCD) is a rare and ultimately fatal metabolic dis-ease that results in extensive neurodegeneration in early infancy. The causal association of MCD with sulfite oxidase deficiency, a known cause of subluxed lenses (ectopia lentis), has only been recently defined. We report a 16-month-old Saudi Arabian male product of a consanguin-eous union, who presented as a neonate with intractable seizures and a failure to thrive. Sub-sequent examinations revealed hypotonia, laryngomalacia, global developmental delay, progressive neurodegeneration and ectopia lentis. Urine analysis revealed elevated sulfocys- tiene, xanthine and hypoxanthine, which suggested MCD. This diagnosis was confirmed by sub-sequent genetic analysis, which disclosed a homozygous MOCS1 mutation. A significant family history of sibling death, prior to diagnosis, from intractable seizures and respiratory distress at three months of age, most likely represents the same affliction and suggests an underestima-tion of MCD worldwide. This case underscores the need to consider and investigate MCD in all cases of intractable infantile seizures. Thus, early diagnosis and confirmatory gene analysis before permanent neurodegeneration is imperative for potential therapeutic intervention.
Feed-forward control of a perturbed backward-facing step flow
Authors: Gautier N. , Aider J.-L.
Published: October 2014

Closed-loop control of an amplifier flow is experimentally investigated. A feed-forward algorithm is implemented to control the flow downstream of a backward-facing step (BFS) perturbed by upstream perturbations. Upstream and downstream data are extracted from real-time velocity fields to compute an ARMAX model used to effect actuation. This work, done at Reynolds number 430, investigates the practical feasibility of this approach which has shown great promise in a recent numerical study by Hervé et al. (J. Fluid Mech., vol. 702, 2012, pp. 26–58). The linear nature of the regime is checked, two-dimensional upstream perturbations are introduced, and the degree to which the flow can be controlled is quantified. The resulting actuation is able to effectively reduce downstream energy levels and fluctuations. The limitations and difficulties of applying such an approach to an experiment are also discussed.
Musk deerMoschus cupreuspersist in the eastern forests of Afghanistan
Authors: Ostrowski Stephane , Rahmani Haqiq , Ali Jan Mohammad , Ali Rita , Zahler Peter
Published: October 2014

Nuristan province, in north-east Afghanistan, holds a significant portion of the country's remaining forests, but because of the inaccessible terrain and the recent history of poor security little is known about the wildlife inhabiting these forests. We conducted transect surveys in central Nuristan and confirmed the presence of musk deerMoschus cupreus> 60 years after the last documented observation of the species in Afghanistan. We found that, in summer, musk deer inhabit remote alpine scrub on scattered rock outcrops and in upper fringes of closed coniferous forests at c. 3,000–3,500 m. They invariably use steep slopes (≥ 20°), which makes them difficult to approach. We built a data-driven geographical model, which predicted that suitable habitat for musk deer in Afghanistan extends over c. 1,300 km2in the contiguous provinces of Nuristan (75.5%), Kunar (14.4%) and Laghman (10.1%). Although relatively vast, the area of habitat potentially available to musk deer in Afghanistan appears to be highly fragmented. Despite indications of unsustainable hunting, this Endangered species persists in Afghanistan and targeted conservation programmes are required to protect it and its forest habitat.
Residential dynamics and neighbourhood conditions of older migrants and native Dutch older adults in Amsterdam, The Netherlands
Authors: VAN DER GREFT SABINE , MUSTERD SAKO , THISSEN FRANS
Published: October 2014

The share of older migrants in Dutch cities is increasing. However, only limited knowledge has been gained about the urban conditions that older migrants live in and how these compare to those of their native Dutch counterparts. This paper contributes to filling this knowledge gap using detailed information on residential patterns, housing conditions and levels of neighbourhood deprivation in the city of Amsterdam in the Netherlands, and links this information to data about housing and neighbourhood satisfaction and perceived safety. Empirical evidence demonstrates that there is strong path dependence with regard to the places in which one finds different groups of older non-Western migrants. Older non-Western migrants in Amsterdam are highly concentrated in disadvantaged neighbourhoods. The number of concentrations has increased significantly over the past decade, as well as the concentration levels. Nevertheless, we did not find indications of social isolation. With regard to housing conditions, we found better conditions for socio-economically similar groups of native Dutch and Surinamese 55+ residents, compared to Turkish and Moroccan 55+ residents. These conditions correspond with levels of housing satisfaction. Surinamese older people are more positive about their neighbourhoods. We hypothesise that this is related to the restructuring of neighbourhoods where Surinamese 55+ residents are concentrated. Although the immediate environment of older non-Western people is characterised by high levels of social deprivation, this does not translate into dissatisfaction with social relations or feelings of lack of safety. This suggests that their residential concentration in particular urban neighbourhoods may also bring significant opportunities.
Human tularemia in Italy. Is it a re-emerging disease?
Authors: D'ALESSANDRO D. , NAPOLI C. , NUSCA A. , BELLA A. , FUNARI E.
Published: October 2014

Tularemia is a contagious infectious disease due toFrancisiella tularensis that can cause serious clinical manifestations and significant mortality if untreated. Although the frequency and significance of the disease has diminished over the last decades in Central Europe, over the past few years, there is new evidence suggesting that tularemia has re-emerged worldwide. To know the real epidemiology of the disease is at the root of correct control measures. In order to evaluate whether tularemia is re-emerging in Italy, data on mortality and morbidity (obtained by the National Institute of Statistics; ISTAT), Italian cases described in the scientific literature and data concerning hospitalizations for tularemia (obtained by the National Hospital Discharge Database) were analysed. From 1979 to 2010, ISTAT reported 474 cases and no deaths. The overall number of cases obtained from the literature review was at least 31% higher than that reported by ISTAT. Moreover, the number of cases reported by ISTAT was 3·5 times smaller than hospitalized cases. In Italy tularemia is sporadic, rarely endemic and self-limiting; but, although the trend of reported tularemia does not support the hypothesis of a re-emerging disease, the study demonstrates a wide underreporting of the disease. The real frequency of the disease should be carefully investigated and taken into account in order to implement specific prevention measures.
Streamlining of Medical Relief to Areas Affected by the Great East Japan Earthquake with the “Area-based/Line-linking Support System”
Authors: Yamanouchi Satoshi , Ishii Tadashi , Morino Kazuma , Furukawa Hajime , Hozawa Atsushi , Ochi Sae , Kushimoto Shigeki
Published: October 2014

Introduction

When disasters that affect a wide area occur, external medical relief teams play a critical role in the affected areas by helping to alleviate the burden caused by surging numbers of individuals requiring health care. Despite this, no system has been established for managing deployed medical relief teams during the subacute phase following a disaster.

After the Great East Japan Earthquake and tsunami, the Ishinomaki Medical Zone was the most severely-affected area. Approximately 6,000 people died or were missing, and the immediate evacuation of approximately 120,000 people to roughly 320 shelters was required. As many as 59 medical teams came to participate in relief activities. Daily coordination of activities and deployment locations became a significant burden to headquarters. The Area-based/Line-linking Support System (Area-Line System) was thus devised to resolve these issues for medical relief and coordinating activities.

Methods

A retrospective analysis was performed to examine the effectiveness of the medical relief provided to evacuees using the Area-Line System with regards to the activities of the medical relief teams and the coordinating headquarters. The following were compared before and after establishment of the Area-Line System: (1) time required at the coordinating headquarters to collect and tabulate medical records from shelters visited; (2) time required at headquarters to determine deployment locations and activities of all medical relief teams; and (3) inter-area variation in number of patients per team.

Results

The time required to collect and tabulate medical records was reduced from approximately 300 to 70 minutes/day. The number of teams at headquarters required to sort through data was reduced from 60 to 14. The time required to determine deployment locations and activities of the medical relief teams was reduced from approximately 150 hours/month to approximately 40 hours/month. Immediately prior to establishment of the Area-Line System, the variation of the number of patients per team was highest. Variation among regions did not increase after establishment of the system.

Conclusion

This descriptive analysis indicated that implementation of the Area-Line System, a systematic approach for long-term disaster medical relief across a wide area, can increase the efficiency of relief provision to disaster-stricken areas.

YamanouchiS,IshiiT,MorinoK,FurukawaH,HozawaA,OchiS,KushimotoS.Streamlining of medical relief to areas affected by the Great East Japan Earthquake with the “Area-based/Line-linking Support System.”Prehosp Disaster Med.2014;29(6):1-9.
Fine Structure of Neurally Differentiated iPS Cells Generated from a Multiple Sclerosis (MS) Patient: A Case Study
Authors: Herszfeld Daniella , Payne Natalie L. , Sylvain Aude , Sun Guizhi , Bernard Claude C. , Clark Joan , Sathananthan Henry
Published: October 2014

We compared the characteristics of neural cells derived from induced pluripotent stem (iPS) cells from a patient with multiple sclerosis versus neurally differentiated control iPS cells of a healthy individual. The iPS cells were differentiated toward the oligodendrocyte lineage using a four-step protocol established for the differentiation of embryonic stem cells. The resulting cell population was immunostained on day 112 of differentiation for the presence of oligodendrocytes and analyzed by transmission electron microscopy (TEM). Both patient and control samples resembled a mixed population of neural cells rather than oligodendroglia of high purity, including neural stem cell-like cells and possibly oligodendrocytes demonstrable by TEM.
Glycolysis and the Pentose Phosphate Pathway after Human Traumatic Brain Injury: Microdialysis Studies Using 1,2-13C2 Glucose
Authors: Jalloh Ibrahim , Carpenter Keri L H , Grice Peter , Howe Duncan J , Mason Andrew , Gallagher Clare N , Helmy Adel , Murphy Michael P , Menon David K , Carpenter T Adrian , Pickard John D , Hutchinson Peter J
Published: October 2014

Increased ‘anaerobic’ glucose metabolism is observed after traumatic brain injury (TBI) attributed to increased glycolysis. An alternative route is the pentose phosphate pathway (PPP), which generates putatively protective and reparative molecules. To compare pathways we employed microdialysis to perfuse 1,2-13C2 glucose into the brains of 15 TBI patients and macroscopically normal brain in six patients undergoing surgery for benign tumors, and to simultaneously collect products for nuclear magnetic resonance (NMR) analysis. 13C enrichment for glycolytic 2,3-13C2 lactate was the median 5.4% (interquartile range (IQR) 4.6–7.5%) in TBI brain and 4.2% (2.4–4.4%) in ‘normal’ brain ( P<0.01). The ratio of PPP-derived 3-13C lactate to glycolytic 2,3-13C2 lactate was median 4.9% (3.6–8.2%) in TBI brain and 6.7% (6.3–8.9%) in ‘normal’ brain. An inverse relationship was seen for PPP-glycolytic lactate ratio versus PbtO2 ( r=−0.5, P=0.04) in TBI brain. Thus, glycolytic lactate production was significantly greater in TBI than ‘normal’ brain. Several TBI patients exhibited PPP—lactate elevation above the ‘normal’ range. There was proportionally greater PPP-derived lactate production with decreasing PbtO2. The study raises questions about the roles of the PPP and glycolysis after TBI, and whether they can be manipulated to achieve a better outcome. This study is the first direct comparison of glycolysis and PPP in human brain.
Transcriptional specialization of human dendritic cell subsets in response to microbial vaccines
Authors: Banchereau Romain , Baldwin Nicole , Cepika Alma-Martina , Athale Shruti , Xue Yaming , Yu Chun I , Metang Patrick , Cheruku Abhilasha , Berthier Isabelle , Gayet Ingrid , Wang Yuanyuan , Ohouo Marina , Snipes LuAnn , Xu Hui , Obermoser Gerlinde , Blankenship Derek , Oh Sangkon , Ramilo Octavio , Chaussabel Damien , Banchereau Jacques , Palucka Karolina , Pascual Virginia
Published: October 2014

The mechanisms by which microbial vaccines interact with human APCs remain elusive. Herein, we describe the transcriptional programs induced in human DCs by pathogens, innate receptor ligands and vaccines. Exposure of DCs to influenza, Salmonella enterica and Staphylococcus aureus allows us to build a modular framework containing 204 transcript clusters. We use this framework to characterize the responses of human monocytes, monocyte-derived DCs and blood DC subsets to 13 vaccines. Different vaccines induce distinct transcriptional programs based on pathogen type, adjuvant formulation and APC targeted. Fluzone, Pneumovax and Gardasil, respectively, activate monocyte-derived DCs, monocytes and CD1c+ blood DCs, highlighting APC specialization in response to vaccines. Finally, the blood signatures from individuals vaccinated with Fluzone or infected with influenza reveal a signature of adaptive immunity activation following vaccination and symptomatic infections, but not asymptomatic infections. These data, offered with a web interface, may guide the development of improved vaccines.
Implementation of Quantitative and Systems Pharmacology in Large Pharma
Authors: Visser S A G , de Alwis D P , Kerbusch T , Stone J A , Allerheiligen S R B
Published: October 2014

Quantitative and systems pharmacology concepts and tools are the foundation of the model‐informed drug development paradigm at Merck for integrating knowledge, enabling decisions, and enhancing submissions. Rigorous prioritization of modeling and simulation activities has enabled key drug development decisions and led to a high return on investment through significant cost avoidance. Critical factors for the successful implementation, examples on impact on decision making with associated return of investment, and drivers for continued success are discussed.

CPT Pharmacometrics Syst. Pharmacol. (2014) 3, e142; doi:10.1038/psp.2014.40; published online 22 October 2014
Lab-on-a-brain: Implantable micro-optical fluidic devices for neural cell analysis in vivo
Authors: Takehara Hiroaki , Nagaoka Akira , Noguchi Jun , Akagi Takanori , Kasai Haruo , Ichiki Takanori
Published: October 2014

The high-resolution imaging of neural cells in vivo has brought about great progress in neuroscience research. Here, we report a novel experimental platform, where the intact brain of a living mouse can be studied with the aid of a surgically implanted micro-optical fluidic device; acting as an interface between neurons and the outer world. The newly developed device provides the functions required for the long-term and high-resolution observation of the fine structures of neurons by two-photon laser scanning microscopy and the microfluidic delivery of chemicals or drugs directly into the brain. A proof-of-concept experiment of single-synapse stimulation by two-photon uncaging of caged glutamate and observation of dendritic spine shrinkage over subsequent days demonstrated a promising use for the present technology.
On-point detection of GM rice in 20 minutes with pullulan as CPA acceleration additive
Authors: Wang Rui , Wu Jian , Zhang Fang , Wang Liu , Ji Feng
Published: October 2014

1% (w/v) concentration of pullulan as a cross-priming isothermal amplification additive has an acceleration effect on nucleic acid amplification. With this property, on-point specific detection of DNA by lateral-flow dipstick within 20 minutes was realized.
Photocatalytic aerobic oxidation of amines to imines on BiVO4 under visible light irradiation
Authors: Yuan Bo , Chong Ruifeng , Zhang Bao , Li Jun , Liu Yan , Li Can
Published: October 2014

BiVO4 was found to be an efficient photocatalyst for selective oxidation of amines to imines with high conversion and selectivity.
Fluorescent polymers from non-fluorescent photoreactive monomers
Authors: Mueller Jan O. , Voll Dominik , Schmidt Friedrich G. , Delaittre Guillaume , Barner-Kowollik Christopher
Published: October 2014

A facile, fast and ambient-temperature avenue towards highly fluorescent polymers is introduced via polymerizing non-fluorescent photoreactive monomers based on light-induced NITEC chemistry, providing a platform technology for fluorescent polymers. The resulting polypyrazolines were analyzed in depth.
Cu/ZnO nanocatalysts in response to environmental conditions: surface morphology, electronic structure, redox state and CO2 activation
Authors: Martínez-Suárez Luis , Frenzel Johannes , Marx Dominik
Published: October 2014

Methanol synthesis is one of the landmarks of heterogeneous catalysis due to the great industrial significance of methanol as a clean liquid fuel and as a raw material for industry.
The photochemistry of inverse dithienylethene switches understood
Authors: Aloïse Stéphane , Yibin Ruan , Hamdi Ismail , Buntinx Guy , Perrier Aurélie , Maurel François , Jacquemin Denis , Takeshita Michinori
Published: October 2014

The photophysical properties of a series of dithienylethenes, free or blocked in an ideal photoactive conformation by an alkyl bridge, are investigated by stationary, ultrafast spectroscopy and state-of-the-art time-dependent density functional theory calculations.
A novel [4 + 3] interpenetrated net containing 7-fold interlocking pseudo-helical chains and exceptional catenane-like motifs
Authors: Song Bai-Qiao , Qin Chao , Zhang Yu-Teng , An Li-Tao , Shao Kui-Zhan , Su Zhong-Min
Published: October 2014

The first example of a [4 + 3] 7-fold interpenetrating network was prepared, showing 7-fold interlocking pseudo-helical chains and a unique catenane-like motif with Hopf links.
Nanocrystalline Pt-CeO2as an efficient catalyst for a room temperature selective reduction of nitroarenes
Authors: Shukla Astha , Singha Rajib Kumar , Sasaki Takehiko , Bal Rajaram
Published: October 2014

We have developed 2–5 nm Pt nanoparticles supported on CeO2nanoparticles which shows chemoselective hydrogenation of nitro compounds in the presence of molecular hydrogen with >99.9% conversion and 99% selectivity at room temperature.
Configurational changes of heme followed by cytochrome c folding reaction
Authors: Choi Jungkweon , Cho Dae Won , Tojo Sachiko , Fujitsuka Mamoru , Majima Tetsuro
Published: October 2014

Although the reduction dynamics of ferric Cyt-coccur within a time range of a few microseconds, the ligand binding and exchange of heme, accompanied by one-electron reduction, depends on the initial configuration of the heme.
Synthesis and biology of cyclic imine toxins, an emerging class of potent, globally distributed marine toxins
Authors: Stivala Craig E. , Benoit Evelyne , Aráoz Rómulo , Servent Denis , Novikov Alexei , Molgó Jordi , Zakarian Armen
Published: October 2014

This review provides an full account of recent progress in discovery, synthesis, biology, and toxicology of a new and fascinating class of toxins known as Cyclic Imine (CI) toxins.
The synthesis of 3-hydroxy-2,4,8-trimethyldec-8-enolides and an approach to 3,4-dihydroxy-2,4,6,8-tetramethyldec-8-enolide
Authors: Botubol-Ares J. M. , Durán-Peña M. J. , Macías-Sánchez A. J. , Hanson J. R. , Collado I. G. , Hernández-Galán R.
Published: October 2014

The enantioselective synthesis of 3, (E)-8, (Z)-8, 20a and 20b is reported using RCM as key step. Based in spectroscopic differences, the structure assigned to the natural product has been revised to that of a γ-butyrolactone.
Donor–acceptor block copolymers carrying pendant PC71BM fullerenes with an ordered nanoscale morphology
Authors: Hufnagel Martin , Fischer Matthias , Thurn-Albrecht Thomas , Thelakkat Mukundan
Published: October 2014

A PC71BM-grafted donor–acceptor block copolymer with enhanced absorption showing a periodic nanostructure of 37 nm both in bulk and in thin films was synthesized by combining KCTP and CRP methods.
A facile synthesis of flower-shaped TiO2/Ag microspheres and their application in photocatalysts
Authors: Zhang Li , Chen Lei , Chen Liangwei , Zhu Guang
Published: October 2014

Novel flower-shaped microspheres (FSMP) TiO2/Ag nanoparticles composites were fabricated by the facile tyrosine-reduced method and used as a photocatalyst for the degradation of MB under light irradiation. The results indicate that as-prepared composite microspheres have a superior photocatalytic activity attributed to higher surface area, increased light absorption capability, the reduction of electron–hole pair recombination.
Modification of the core–shell ratio to prepare PB-g-(MMA-co-St-co-GMA) particle-toughened poly(butylene terephthalate) and polycarbonate blends with balanced stiffness and toughness
Authors: Guo Yang , Sun Shulin , Zhang Huixuan
Published: October 2014

Particles with a modified core–shell ratio provide an effective way to prepare polymer blends with a superior balance of toughness and stiffness.
Actinide elements and germanium: a first-principles density functional theory investigation of the electronic and magnetic properties of ApGe (Ap = Ac–Lr) diatoms
Authors: Zhao Run-Ning , Yuan Yanhong , Han Ju-Guang , Duan Yuhua
Published: October 2014

The geometry and electronic and magnetic properties of ApGe (Ap = Ac–Lr) diatoms have been studied using first-principles density functional theory, with relativistic effects being taken into account.
Magnetic field induced quantum dot brightening in liquid crystal synergized magnetic and semiconducting nanoparticle composite assemblies
Authors: Amaral Jose Jussi , Wan Jacky , Rodarte Andrea L. , Ferri Christopher , Quint Makiko T. , Pandolfi Ronald J. , Scheibner Michael , Hirst Linda S. , Ghosh Sayantani
Published: October 2014

Magnetic and semiconducting nanoparticles are co-assembled in a liquid crystalline matrix to form composite aggregates that display continuous brightening with the application of small external magnetic fields at room temperature.
Understanding and overcoming shear alignment of fibers during extrusion
Authors: Martin Joshua J. , Riederer Michael S. , Krebs Melissa D. , Erb Randall M.
Published: October 2014

Fiber alignment is the defining architectural characteristic of discontinuous fiber composites and is dictated by shear-dominated processing techniques. Here we study how magnetic alignment can be used to overcome shear, maintain fiber alignment, and arrest Jeffrey orbits.
Red Flags: Barriers to Listening and Spoken Language in Children with Hearing Loss
Authors: Bell Andrea , Houston K. Todd
Published: October 2014

To ensure optimal auditory development for the acquisition of spoken language, children with hearing loss require early diagnosis, effective ongoing audiological management, well fit and maintained hearing technology, and appropriate family-centered early intervention. When these elements are in place, children with hearing loss can achieve developmental and communicative outcomes that are comparable to their hearing peers. However, for these outcomes to occur, clinicians—early interventionists, speech-language pathologists, and pediatric audiologists—must participate in a dynamic process that requires careful monitoring of countless variables that could impact the child's skill acquisition. This paper addresses some of these variables or “red flags,” which often are indicators of both minor and major issues that clinicians may encounter when delivering services to young children with hearing loss and their families.
Secure communications via sending artificial noise by both transmitter and receiver: optimum power allocation to minimise the insecure region
Authors: Li Wei , Tang Yanqun , Ghogho Mounir , Wei Jibo , Xiong Chunlin
Published: October 2014

A novel approach for ensuring confidential wireless communication is proposed and analysed from a geometrical perspective. In this method, both the legitimate receiver and transmitter generate artificial noise (AN) to impair the eavesdropper's channel. The authors use the concept of insecure region to characterise the security performance when the eavesdropper's channel is unknown. The insecure region is defined as the region where the eavesdropper may decode the secret message. With the aim of minimising the size of the insecure region, an optimum power allocation strategy between the information bearing signal and the AN is proposed. Simulation results show that the proposed method achieves a good performance.
Minimum transmit power under/considering relay selection for asymmetric two‐way relaying networks
Authors: Jie Yang , Xue‐hong Cao , Rui Chen , Xiong‐li Rui
Published: October 2014

Two‐way amplify‐and‐forward (AF) relaying networks have been widely studied because of their simplicity and high spectral efficiency characteristics. Power allocation (PA) and relay selection (RS) for two‐way AF relaying systems are of particular interest. However, most of the previous studies only consider the PA and RS for these systems with symmetric traffic requirements. In this study, the authors’ focus on the minimum transmit power (MTP) under/considering RS for asymmetric two‐way relaying networks. The authors’ derive the MTP required for two‐way AF relaying transmission with asymmetric traffic requirements, and propose an optimal RS criterion based on the derived MTP. First, the outage probability (OP) of two‐way relaying transmission based on statistical channel state information (CSI) is derived. Then, by converting a geometric programming to a convex optimisation problem, the closed‐form solution of the PA aiming at minimising total transmit power under the OP constraints is obtained. Lastly, a distributed RS criterion based on MTP is proposed. In addition, the proposed RS scheme only needs local statistical CSI rather than instantaneous CSI, which makes it simple in implementation. Numerical results demonstrate that the proposed scheme can significantly decrease the power consumption under the predefined OP constraints.
Detection with erasure for error‐propagation mitigation in decode‐and‐forward relaying with general pulse amplitude‐modulated/quadrature amplitude‐modulated signals
Authors: Lee Yinman , Shieh Hong‐Wei
Published: October 2014

In the research of decode‐and‐forward (DF) cooperative communications, it is often supposed that the included relay only transmits correctly decoded signals. This simplifies the analysis of DF cooperation. However, in practical circumstances, erroneous messages may be forwarded which makes the decision at the destination even worst. In this study, the authors formulate a special detection way, named ‘detection with erasure’, to make certain that the relay‐forwarded signals are mostly correct. Specifically, whenever the decoded result at the relay falls into some preset ‘erasure regions’, the relay will not process and transmit it anymore. This effectively prevents the forwarding of erroneous messages. With general pulse amplitude‐modulated or squared quadrature amplitude‐modulated signals, the authors demonstrate that these erasure regions can be adjusted to minimise the end‐to‐end symbol error rate (SER). This detection scheme can be extended to be used in the DF cooperation employing multiple relays as well. Simulations reveal that in terms of the end‐to‐end SER performance, the proposed detection with erasure can outperform some signal‐to‐noise ratio threshold‐based relaying approaches, and can perform quite similarly as compared with those decoding/combining methods realised at the destination with the advantage of less channel state information exchange.
Strong and weak, unsteady reconfiguration and its impact on turbulence structure within plant canopies
Authors: Pan Ying , Follett Elizabeth , Chamecki Marcelo , Nepf Heidi
Published: October 2014

Flexible terrestrial and aquatic plants bend in response to fluid motion and this reconfiguration mechanism reduces drag forces, which protects against uprooting or breaking under high winds and currents. The impact of reconfiguration on the flow can be described quantitatively by introducing a drag coefficient that decreases as a power-law function of velocity with a negative exponent known as the Vogel number. In this paper, two case studies are conducted to examine the connection between reconfiguration and turbulence dynamics within a canopy. First, a flume experiment was conducted with a model seagrass meadow. As the flow rate increased, both the mean and unsteady one-dimensional linear elastic reconfiguration increased. In the transition between the asymptotic regimes of negligible and strong reconfiguration, there is a regime of weak reconfiguration, in which the Vogel number achieved its peak negative value. Second, large-eddy simulation was conducted for a maize canopy, with different modes of reconfiguration characterized by increasingly negative values of the Vogel number. Even though the mean vertical momentum flux was constrained by field measurements, changing the mode of reconfiguration altered the distribution, strength, and fraction of momentum carried by strong and weak events. Despite the differences between these two studies, similar effects of the Vogel number on turbulence dynamics were demonstrated. In particular, a more negative Vogel number leads to a more positive peak of the skewness of streamwise velocity within the canopy, which indicates a preferential penetration of strong events into a vegetation canopy. We consider different reconfiguration geometry (one- and two-dimensional) and regime (negligible, weak, and strong) that can apply to a wide range of terrestrial and aquatic canopies.
Colloidal quantum dot solar cells on curved and flexible substrates
Authors: Kramer Illan J. , Moreno-Bautista Gabriel , Minor James C. , Kopilovic Damir , Sargent Edward H.
Published: October 2014

Colloidal quantum dots (CQDs) are semiconductor nanocrystals synthesized with, processed in, and deposited from the solution phase, potentially enabling low-cost, facile manufacture of solar cells. Unfortunately, CQD solar cell reports, until now, have only explored batch-processing methods—such as spin-coating—that offer limited capacity for scaling. Spray-coating could offer a means of producing uniform colloidal quantum dot films that yield high-quality devices. Here, we explore the versatility of the spray-coating method by producing CQD solar cells in a variety of previously unexplored substrate arrangements. The potential transferability of the spray-coating method to a roll-to-roll manufacturing process was tested by spray-coating the CQD active layer onto six substrates mounted on a rapidly rotating drum, yielding devices with an average power conversion efficiency of 6.7%. We further tested the manufacturability of the process by endeavoring to spray onto flexible substrates, only to find that spraying while the substrate was flexed was crucial to achieving champion performance of 7.2% without compromise to open-circuit voltage. Having deposited onto a substrate with one axis of curvature, we then built our CQD solar cells onto a spherical lens substrate having two axes of curvature resulting in a 5% efficient device. These results show that CQDs deposited using our spraying method can be integrated to large-area manufacturing processes and can be used to make solar cells on unconventional shapes.
Influence of interaction parameters on laser shock wave induced dynamic strain on 7050 aluminum alloy surface
Authors: Cao Yupeng , Feng Aixin , Hua Guoran
Published: October 2014

To study the effects of overlay and laser power density on dynamic strain, the dynamic strain induced by a pulsed laser shock wave on a 7050 aluminum alloy surface was measured using a polyvinylidene fluoride (PVDF) piezoelectric sensor. A dynamic strain model of the 7050 aluminum alloy surface under the pulsed laser shock wave load was established based on our hypothesis. The results showed that, under the influence of a constraining layer, the laser's thermal effect was negligible when the laser power density was higher than 1.4 GW/cm2. When the material surface was loaded by the laser for 140 ns, a surface wave was detected by the PVDF sensor, but when the laser power density was less than 12.7 GW/cm2, coupling between the shock wave and the surface wave did not occur. The dynamic stress-strain relationship curve of the 7050 aluminum alloy under the high strain rate of the pulsed laser shock wave was similar to the static stress-strain relationship curve of the 7050 aluminum alloy under static tensile conditions. The experimental results were consistent with the results of the dynamic strain model of the 7050 aluminum alloy surface under the pulsed laser shock wave load.
Resonant absorption in semiconductor nanowires and nanowire arrays: Relating leaky waveguide modes to Bloch photonic crystal modes
Authors: Fountaine Katherine T. , Whitney William S. , Atwater Harry A.
Published: October 2014

We present a unified framework for resonant absorption in periodic arrays of high index semiconductor nanowires that combines a leaky waveguide theory perspective and that of photonic crystals supporting Bloch modes, as array density transitions from sparse to dense. Full dispersion relations are calculated for each mode at varying illumination angles using the eigenvalue equation for leaky waveguide modes of an infinite dielectric cylinder. The dispersion relations along with symmetry arguments explain the selectivity of mode excitation and spectral red-shifting of absorption for illumination parallel to the nanowire axis in comparison to perpendicular illumination. Analysis of photonic crystal band dispersion for varying array density illustrates that the modes responsible for resonant nanowire absorption emerge from the leaky waveguide modes.
Multilevel unipolar resistive switching with negative differential resistance effect in Ag/SiO2/Pt device
Authors: Sun Haitao , Liu Qi , Long Shibing , Lv Hangbing , Banerjee Writam , Liu Ming
Published: October 2014

In this paper, we report a multilevel unipolar resistive switching (RS) phenomenon with negative differential resistance (NDR) effect in Ag/SiO2/Pt sandwich structure. After positive electroforming process with low compliance current (ICC, 10 nA), a conductive filament consisting of isolated Ag nanocrystals is formed inside SiO2 layer. Then, an abnormal unipolar resistive switching (RESET voltage is larger than SET voltage) with NDR effect is obtained under negative voltage sweep without ICC. Based on I-V fitting and temperature dependence of the resistance results, we suggest that the abnormal unipolar RS is dominated by the charging/discharging of carriers in Ag nanocrystals. In addition, we demonstrate that the unipolar RS exhibits good performances, including large Roff/Ron ratio, high uniformity, long retention time, and multilevel storage potential.
Giant flexoelectricity in Ba0.6Sr0.4TiO3/Ni0.8Zn0.2Fe2O4 composite
Authors: Li Yong , Shu Longlong , Huang Wenbin , Jiang Xiaoning , Wang Hong
Published: October 2014

Enhanced flexoelectricity in perovskite ceramics and single crystals has been reported before. In this letter, 3-3 ceramic-ceramic Ba0.6Sr0.4TiO3/Ni0.8Zn0.2Fe2O4 composite with a colossal permittivity was employed in the conventional pure bending experiment in order to examine the transverse flexoelectric response. The measured flexoelectric coefficient at 30 Hz is 128 μC/m and varies to 16 μC/m with the frequency increasing from 30 Hz to 120 Hz, mainly due to the inverse correlation between the permittivity and the frequency. This result reveals the permittivity dependence of flexoelectric coefficient in the frequency dispersion materials, suggesting that the giant permittivity composites can be good flexoelectric materials.
A comparative analysis between the tracking solutions implemented on a photovoltaic string
Authors: Alexandru Cătălin
Published: October 2014

The paper deals with a comparative analysis (in terms of energetic efficiency) between the mono-axis and dual-axis tracking solutions implemented on a photovoltaic (PV) string. The study reveals which solution is more efficient in the geographical area of Braşov, and under which conditions. The tracking efficiencies of the mono-axis and dual-axis systems are compared considering two orientation programs: seasonal and annual. Taking into account the technical and economical aspects, besides the energy gain of the dual-axis system, it was concluded that a mono-axis tracking system is preferred for the studied geographical area. The study is performed by using the virtual prototype of the PV tracking system, which is approached in mechatronic concept. An algorithm for the optimal design of the step-by-step tracking law is also developed, the maximization of the energetic efficiency of the PV string with solar tracker being the optimization goal. Finally, experimental data are used to validate the simulation results.