bluuebunny/crossref_metadata_2025 huggingface dataset:
The Gcn4 transcription factor reduces protein synthesis capacity and extends yeast lifespan
Authors: Mittal Nitish , Guimaraes Joao C. , Gross Thomas , Schmidt Alexander , Vina-Vilaseca Arnau , Nedialkova Danny D. , Aeschimann Florian , Leidel Sebastian A. , Spang Anne , Zavolan Mihaela
Published: August 2017

In Saccharomyces cerevisiae, deletion of large ribosomal subunit protein-encoding genes increases the replicative lifespan in a Gcn4-dependent manner. However, how Gcn4, a key transcriptional activator of amino acid biosynthesis genes, increases lifespan, is unknown. Here we show that Gcn4 acts as a repressor of protein synthesis. By analyzing the messenger RNA and protein abundance, ribosome occupancy and protein synthesis rate in various yeast strains, we demonstrate that Gcn4 is sufficient to reduce protein synthesis and increase yeast lifespan. Chromatin immunoprecipitation reveals Gcn4 binding not only at genes that are activated, but also at genes, some encoding ribosomal proteins, that are repressed upon Gcn4 overexpression. The promoters of repressed genes contain Rap1 binding motifs. Our data suggest that Gcn4 is a central regulator of protein synthesis under multiple perturbations, including ribosomal protein gene deletions, calorie restriction, and rapamycin treatment, and provide an explanation for its role in longevity and stress response.
Reconstructing cell cycle and disease progression using deep learning
Authors: Eulenberg Philipp , Köhler Niklas , Blasi Thomas , Filby Andrew , Carpenter Anne E. , Rees Paul , Theis Fabian J. , Wolf F. Alexander
Published: August 2017

We show that deep convolutional neural networks combined with nonlinear dimension reduction enable reconstructing biological processes based on raw image data. We demonstrate this by reconstructing the cell cycle of Jurkat cells and disease progression in diabetic retinopathy. In further analysis of Jurkat cells, we detect and separate a subpopulation of dead cells in an unsupervised manner and, in classifying discrete cell cycle stages, we reach a sixfold reduction in error rate compared to a recent approach based on boosting on image features. In contrast to previous methods, deep learning based predictions are fast enough for on-the-fly analysis in an imaging flow cytometer.
Environmental stress is the major cause of transcriptomic and proteomic changes in GM and non-GM plants
Authors: Batista Rita , Fonseca Cátia , Planchon Sébastien , Negrão Sónia , Renaut Jenny , Oliveira M. Margarida
Published: August 2017

The approval of genetically modified (GM) crops is preceded by years of intensive research to demonstrate safety to humans and environment. We recently showed that in vitro culture stress is the major factor influencing proteomic differences of GM vs. non-GM plants. This made us question the number of generations needed to erase such “memory”. We also wondered about the relevance of alterations promoted by transgenesis as compared to environment-induced ones. Here we followed three rice lines (1-control, 1-transgenic and 1-negative segregant) throughout eight generations after transgenesis combining proteomics and transcriptomics, and further analyzed their response to salinity stress on the F6 generation. Our results show that: (a) differences promoted during genetic modification are mainly short-term physiological changes, attenuating throughout generations, and (b) environmental stress may cause far more proteomic/transcriptomic alterations than transgenesis. Based on our data, we question what is really relevant in risk assessment design for GM food crops.
Pleomorphic bacteria-like structures in human blood represent non-living membrane vesicles and protein particles
Authors: Martel Jan , Wu Cheng-Yeu , Huang Pei-Rong , Cheng Wei-Yun , Young John D.
Published: August 2017

Although human blood is believed to be a sterile environment, recent studies suggest that pleomorphic bacteria exist in the blood of healthy humans. These studies have led to the development of “live-blood analysis,” a technique used by alternative medicine practitioners to diagnose various human conditions, including allergies, cancer, cardiovascular disease and septicemia. We show here that bacteria-like vesicles and refringent particles form in healthy human blood observed under dark-field microscopy. These structures gradually increase in number during incubation and show morphologies reminiscent of cells undergoing division. Based on lipid analysis and Western blotting, we show that the bacteria-like entities consist of membrane vesicles containing serum and exosome proteins, including albumin, fetuin-A, apolipoprotein-A1, alkaline phosphatase, TNFR1 and CD63. In contrast, the refringent particles represent protein aggregates that contain several blood proteins. 16S rDNA PCR analysis reveals the presence of bacterial DNA in incubated blood samples but also in negative controls, indicating that the amplified sequences represent contaminants. These results suggest that the bacteria-like vesicles and refringent particles observed in human blood represent non-living membrane vesicles and protein aggregates derived from blood. The phenomena observed during live-blood analysis are therefore consistent with time-dependent decay of cells and body fluids during incubation ex vivo.
Development of oriC-plasmids for use in Mycoplasma hyorhinis
Authors: Ishag Hassan Z. A. , Xiong Qiyan , Liu Maojun , Feng Zhixin , Shao Guoqing
Published: August 2017

Mycoplasma hyorhinis (M. hyorhinis) is an opportunistic pig pathogen, belonging to the class Mollicutes. It causes polyserositis, arthritis and cancers in vitro, increasing attention of the researchers. Currently, there is no available genetic tool to manipulate its genome. This study describes a development of oriC-plasmids harboring either large (pGEMT-LoriC) or minimum (pGEMT-MoriC) origin of replication (oriC) of M. hyorhinis along with tetracycline resistance marker.These plasmids were successfully transformed into M. hyorhinis with average transformation frequency of 1.5 × 10−4 and 2.0 × 10−5 transformants/CFU for pGEMT-LoriC and pGEMT-MoriC respectively, and were integrated at the chromosomal oriC as well as remained freely replicating. We also constructed a Mini-oriC-HT1 targeting plasmid by inclusion of hlyC arms and was used to inactivate hlyC at average frequency of 50%. The efficiency of hlyC inactivation was further improved (by 90%) when Mini-oriC-HT2 that contains E. coli recA was used. In both cases, hemolysin mutant bacteria diminished the ability to lyse mouse RBCs compared to wild-type (P < 0.001). OriC-plasmids described in this study may, therefore open the way for functional genomics in M. hyorhinis. Furthermore, this is a first study demonstrated the gene associated with a hemolytic phenotype in mycoplasmas.
Structural and molecular comparison of bacterial and eukaryotic trigger factors
Authors: Ries Fabian , Carius Yvonne , Rohr Marina , Gries Karin , Keller Sandro , Lancaster C. Roy D. , Willmund Felix
Published: August 2017

A considerably small fraction of approximately 60–100 proteins of all chloroplast proteins are encoded by the plastid genome. Many of these proteins are major subunits of complexes with central functions within plastids. In comparison with other subcellular compartments and bacteria, many steps of chloroplast protein biogenesis are not well understood. We report here on the first study of chloroplast-localised trigger factor. In bacteria, this molecular chaperone is known to associate with translating ribosomes to facilitate the folding of newly synthesized proteins. Chloroplast trigger factors of the unicellular green algae Chlamydomonas reinhardtii and the vascular land plant Arabidopsis thaliana were characterized by biophysical and structural methods and compared to the Escherichia coli isoform. We show that chloroplast trigger factor is mainly monomeric and displays only moderate stability against thermal unfolding even under mild heat-stress conditions. The global shape and conformation of these proteins were determined in solution by small-angle X-ray scattering and subsequent ab initio modelling. As observed for bacteria, plastidic trigger factors have a dragon-like structure, albeit with slightly altered domain arrangement and flexibility. This structural conservation despite low amino acid sequence homology illustrates a remarkable evolutionary robustness of chaperone conformations across various kingdoms of life.
Mutation E87Q of the β1-subunit impairs the maturation of the cardiac voltage-dependent sodium channel
Authors: Baroni Debora , Picco Cristiana , Moran Oscar
Published: August 2017

Voltage-dependent sodium channels are responsible of the rising phase of the action potential in excitable cells. These membrane integral proteins are composed by a pore-forming α-subunit, and one or more auxiliary β subunits. Mutation E87Q of the β1 subunit is correlated with Brugada syndrome, a genetic disease characterised by ventricular fibrillation, right precordial ST segment elevation on ECG and sudden cardiac death. Heterologous expression of E87Q-β1 subunit in CHO cells determines a reduced sodium channel functional expression. The effect the E87Q mutation of the β1 subunit on sodium currents and α protein expression is correlated with a reduced availability of the mature form of the α subunit in the plasma membrane. This finding offers a new target for the treatment of the Brugada syndrome, based on protein maturation management. This work highlights the role played by the β1 subunit in the maturation and expression of the entire sodium channel complex and underlines how the defective interaction between the sodium channel constituents could lead to a disabling pathological condition.
Carnot efficiency is reachable in an irreversible process
Authors: Lee Jae Sung , Park Hyunggyu
Published: August 2017

In thermodynamics, there exists a conventional belief that “the Carnot efficiency is reachable only in the reversible (zero entropy production) limit of nearly reversible processes.” However, there is no theorem proving that the Carnot efficiency is unattainable in an irreversible process. Here, we show that the Carnot efficiency is reachable in an irreversible process through investigation of the Feynman-Smoluchowski ratchet (FSR). We also show that it is possible to enhance the efficiency by increasing the irreversibility. Our result opens a new possibility of designing an efficient heat engine in a highly irreversible process and also answers the long-standing question of whether the FSR can operate with the Carnot efficiency.
Avascular Necrosis of Femoral Head: A Metabolomic, Biophysical, Biochemical, Electron Microscopic and Histopathological Characterization
Authors: Narayanan Aswath , Khanchandani Prakash , Borkar Roshan M. , Ambati Chandrashekar Reddy , Roy Arun , Han Xu , Bhoskar Ritesh N , Ragampeta Srinivas , Gannon Francis , Mysorekar Vijaya , Karanam Balasubramanyam , V Sai Muthukumar , Sivaramakrishnan Venketesh
Published: August 2017

Avascular necrosis of the femur head (AVNFH) is a debilitating disease caused due to the use of alcohol, steroids, following trauma or unclear (idiopathic) etiology, affecting mostly the middle aged population. Clinically AVNFH is associated with impaired blood supply to the femoral head resulting in bone necrosis and collapse. Although Homocysteine (HC) has been implicated in AVNFH, levels of homocysteine and its associated pathway metabolites have not been characterized. We demonstrate elevated levels of homocysteine and concomitantly reduced levels of vitamins B6 and B12, in plasma of AVNFH patients. AVNFH patients also had elevated blood levels of sodium and creatinine, and reduced levels of random glucose and haemoglobin. Biophysical and ultrastructural analysis of AVNFH bone revealed increased remodelling and reduced bone mineral density portrayed by increased carbonate to phosphate ratio and decreased Phosphate to amide ratio together with disrupted trabeculae, loss of osteocytes, presence of calcified marrow, and elevated expression of osteocalcin in the osteoblasts localized in necrotic regions. Taken together, our studies for the first time characterize the metabolomic, pathophysiological and morphometric changes associated with AVNFH providing insights for development of new markers and therapeutic strategies for this debilitating disorder.
FUT2 non-secretor status is associated with altered susceptibility to symptomatic enterotoxigenic Escherichia coli infection in Bangladeshis
Authors: Mottram Lynda , Wiklund Gudrun , Larson Göran , Qadri Firdausi , Svennerholm Ann-Mari
Published: August 2017

Polymorphisms of the FUT2 gene alters glycan ABO(H) blood group and Lewis antigen expression (commonly known as non-secretor status) in the small intestinal mucosa. Whilst non-secretor status affects 20% of the population worldwide, it has been reported to be present in up to 40% of all Bangladeshis. Furthermore, Bangladeshi children are reportedly more susceptible to symptomatic enterotoxigenic Escherichia coli (ETEC) infection if they are non-secretors. Therefore, in an attempt to identify a non-secretor status genotypic biomarker of altered susceptibility to ETEC infection, we used the 1000 Genomes Project to identify three population related non-synonymous FUT2 single nucleotide polymorphisms (SNPs). We then assessed the genotypic frequency of these SNPs in Bangladeshi children who had been clinically monitored for ETEC infection. One novel missense FUT2 SNP, rs200157007-TT and the earlier established rs601338-AA SNP were shown to be causing non-secretor status, with these SNPs being associated with symptomatic but not asymptomatic ETEC infection. Moreover, rs200157007-TT and rs601338-AA were associated with symptomatic but not asymptomatic ETEC infection irrespective of the child’s Lewis secretor status, suggesting FUT2, the regulator of Lewis and ABO(H) antigens in the intestinal mucosa, could be a host genotypic feature affecting susceptibility to ETEC infection.
Effects of Intensive Blood Pressure Reduction on Acute Intracerebral Hemorrhage: A Systematic Review and Meta-analysis
Authors: Gong Shun , Lin Chao , Zhang Danfeng , Kong Xiangyi , Chen Jigang , Wang Chunhui , Li Zhenxing , Chen Rongbin , Sheng Ping , Dong Yan , Hou Lijun
Published: August 2017

Current opinions about the effect of intensive blood pressure (BP) reduction for acute intracerebral hemorrhage (ICH) are inconsistent. We performed a meta-analysis to evaluate the efficacy and safety of intensive BP reduction for acute ICH by analyzing data from several recent randomized controlled trials (RCTs). There were six eligible studies that met the inclusion criteria, for a total of 4,385 acute ICH patients in this meta-analysis. After analyzing these data, we found differences between intensive and standard BP lowering treatment groups in total mortality rates, unfavorable outcomes, hematoma expansion, neurologic deterioration, and severe hypotension were not significant. Moreover, compared with the standard treatment, the rate of renal adverse event in intensive treatment group was significantly higher. The intensive treatment approach was recommended in the following situations: (1) longer prehospital duration; (2) lower National Institute of Health stroke scale (NIHSS) score; (3) no hypertension history.
Two-dimensional photonic crystal Bragg lasers with triangular lattice for monolithic coherent beam combining
Authors: Zhu Yeyu , Zhao Yunsong , Zhu Lin
Published: August 2017

We demonstrate an electrically pumped, single-mode, large area, edge-emitting InGaAsP/InP two-dimensional photonic crystal (PC) Bragg laser with triangular lattice. The laser operates in the single transverse and longitudinal modes with a single lobe, near-diffraction-limited far field. We compare the performance of the triangular-lattice PC Bragg laser with the rectangular-lattice PC Bragg laser fabricated from the same wafer and find that their performances are comparable. Then, we combine two single triangular-lattice PC Bragg lasers that tilt to opposite directions by taking advantage of the symmetry of the single emitter cavity mode. The measurement results show that the combined PC Bragg lasers provide the near-diffraction-limited output beam, and the single wavelength operation is also maintained in the coherently combined broad-area PC Bragg lasers.
Calcium ion regulation by BAPTA-AM and ruthenium red improved the fertilisation capacity and developmental ability of vitrified bovine oocytes
Authors: Wang Na , Hao Hai-Sheng , Li Chong-Yang , Zhao Ya-Han , Wang Hao-Yu , Yan Chang-Liang , Du Wei-Hua , Wang Dong , Liu Yan , Pang Yun-Wei , Zhu Hua-Bin , Zhao Xue-Ming
Published: August 2017

Vitrification reduces the fertilisation capacity and developmental ability of mammalian oocytes; this effect is closely associated with an abnormal increase of cytoplasmic free calcium ions ([Ca2+]i). However, little information about the mechanism by which vitrification increases [Ca2+]i levels or a procedure to regulate [Ca2+]i levels in these oocytes is available. Vitrified bovine oocytes were used to analyse the effect of vitrification on [Ca2+]i, endoplasmic reticulum Ca2+ (ER Ca2+), and mitochondrial Ca2+ (mCa2+) levels. Our results showed that vitrification, especially with dimethyl sulfoxide (DMSO), can induce ER Ca2+ release into the cytoplasm, consequently increasing the [Ca2+]i and mCa2+ levels. Supplementing the cells with 10 μM 1,2-bis (o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid (BAPTA-AM or BAPTA) significantly decreased the [Ca2+]i level and maintained the normal distribution of cortical granules in the vitrified bovine oocytes, increasing their fertilisation ability and cleavage rate after in vitro fertilisation (IVF). Treating vitrified bovine oocytes with 1 μM ruthenium red (RR) significantly inhibited the Ca2+ flux from the cytoplasm into mitochondria; maintained normal mCa2+ levels, mitochondrial membrane potential, and ATP content; and inhibited apoptosis. Treating vitrified oocytes with a combination of BAPTA and RR significantly improved embryo development and quality after IVF.
Spectral control of elastic dynamics in metallic nano-cavities
Authors: Ulrichs Henning , Meyer Dennis , Döring Florian , Eberl Christian , Krebs Hans-Ulrich
Published: August 2017

We show how the elastic response of metallic nano-cavities can be tailored by tuning the interplay with an underlying phononic superlattice. In particular, we exploit ultrafast optical excitation in order to address a resonance mode in a tungsten thin film, grown on top of a periodic MgO/ZrO2 multilayer. Setting up a simple theoretical model, we can explain our findings by the coupling of the resonance in the tungsten to an evanescent surface mode of the superlattice. To demonstrate a second potential benefit of our findings besides characterization of elastic properties of multilayer samples, we show by micromagnetic simulation how a similar structure can be utilized for magneto-elastic excitation of exchange-dominated spin waves.
Limited locomotive ability relaxed selective constraints on molluscs mitochondrial genomes
Authors: Sun Shao’e , Li Qi , Kong Lingfeng , Yu Hong
Published: August 2017

Mollusca are the second largest phylum in the animal kingdom with different types of locomotion. Some molluscs are poor-migrating, while others are free-moving or fast-swimming. Most of the energy required for locomotion is provided by mitochondria via oxidative phosphorylation. Here, we conduct a comparative genomic analysis of 256 molluscs complete mitochondrial genomes and evaluate the role of energetic functional constraints on the protein-coding genes, providing a new insight into mitochondrial DNA (mtDNA) evolution. The weakly locomotive molluscs, compared to strongly locomotive molluscs, show significantly higher Ka/Ks ratio, which suggest they accumulated more nonsynonymous mutations in mtDNA and have experienced more relaxed evolutionary constraints. Eleven protein-coding genes (CoxI, CoxII, ATP6, Cytb, ND1-6, ND4L) show significant difference for Ka/Ks ratios between the strongly and weakly locomotive groups. The relaxation of selective constraints on Atp8 arise in the common ancestor of bivalves, and the further relaxation occurred in marine bivalves lineage. Our study thus demonstrates that selective constraints relevant to locomotive ability play an essential role in evolution of molluscs mtDNA.
High expression FUT1 and B3GALT5 is an independent predictor of postoperative recurrence and survival in hepatocellular carcinoma
Authors: Kuo Huan-Hsien , Lin Ruey-Jen , Hung Jung-Tung , Hsieh Chung-Bao , Hung Tsai-Hsien , Lo Fei-Yun , Ho Ming-Yi , Yeh Chau-Ting , Huang Yen-Lin , Yu John , Yu Alice L.
Published: August 2017

Cancer may arise from dedifferentiation of mature cells or maturation-arrested stem cells. Previously we reported that definitive endoderm from which liver was derived, expressed Globo H, SSEA-3 and SSEA-4. In this study, we examined the expression of their biosynthetic enzymes, FUT1, FUT2, B3GALT5 and ST3GAL2, in 135 hepatocellular carcinoma (HCC) tissues by qRT-PCR. High expression of either FUT1 or B3GALT5 was significantly associated with advanced stages and poor outcome. Kaplan Meier survival analysis showed significantly shorter relapse-free survival (RFS) for those with high expression of either FUT1 or B3GALT5 (P = 0.024 and 0.001, respectively) and shorter overall survival (OS) for those with high expression of B3GALT5 (P = 0.017). Combination of FUT1 and B3GALT5 revealed that high expression of both genes had poorer RFS and OS than the others (P < 0.001). Moreover, multivariable Cox regression analysis identified the combination of B3GALT5 and FUT1 as an independent predictor for RFS (HR: 2.370, 95% CI: 1.505–3.731, P < 0.001) and OS (HR: 2.153, 95% CI: 1.188–3.902, P = 0.012) in HCC. In addition, the presence of Globo H, SSEA-3 and SSEA-4 in some HCC tissues and their absence in normal liver was established by immunohistochemistry staining and mass spectrometric analysis.
The environmental impacts of one of the largest tailing dam failures worldwide
Authors: Hatje Vanessa , Pedreira Rodrigo M. A. , de Rezende Carlos Eduardo , Schettini Carlos Augusto França , de Souza Gabriel Cotrim , Marin Danieli Canaver , Hackspacher Peter Christian
Published: August 2017

The impacts of the SAMARCO iron tailing spill along more than 650 km, between the dam and the plume of the Doce River in the Atlantic, were assessed by the determination of toxic metals. The tailing spill caused a substantial increase in suspended sediment loads (up to 33,000 mg L−1), in addition to large depositions of waste along the Doce basin. The highest estimated transport of dissolved metals was observed for Fe (58.8 μg s−1), Ba (37.9 μg s−1) and Al (25.0 μg s−1). Sediments reached the highest enrichment factors (EFs) for Hg (4,234), Co (133), Fe (43), and Ni (16), whereas As (55), Ba (64), Cr (16), Cu (17), Mn (41), Pb (38) and Zn (82) highest EFs were observed for suspended particulate matter (SPM). Iron, As, Hg, Mn exceeded sediment quality guidelines. Therefore, the risk of occurrence of adverse effects is highly possible, not only due to the dam failure, but also due to the Fe mining and the artisan Au mining. Heavy rain episodes will likely cause enhanced erosion, remobilization, and transport of contaminated particles, sustaining high inputs of SPM and metals for the years to come and threatening the ecosystem services.
Simultaneous measurement of transverse load and temperature using hybrid structured fiber-optic Fabry–Perot interferometer
Authors: Wu Yongfeng , Zhang Yundong , Wu Jing , Yuan Ping
Published: August 2017

We experimentally demonstrated a novel fiber-optic hybrid structured Fabry–Perot interferometer with special air-cavity for simultaneous measurement of transverse load and temperature. By the linear phase finite impulse response filters, the transverse load sensitivities of the air-cavity and the silica-cavity are 1272.71 pm/N and −53.07 pm/N, respectively, and temperature sensitivities of the air-cavity and silica-cavity are 1.1 pm/°C and 14 pm/°C. Thus, the different sensitivities of silica-cavity and air-cavity to transverse load and temperature indicate that such a structure can be used to simultaneously measure transverse load and temperature.
Creation of a multi-segmented optical needle with prescribed length and spacing using the radiation pattern from a sectional-uniform line source
Authors: Yu Yanzhong , Huang Han , Zhou Mianmian , Zhan Qiwen
Published: August 2017

This paper presents a method to generate a multi-segmented optical needle with a strong longitudinally polarized field, uniform intensity along the optical axis, and a transverse size (~0.36λ). The length of each segment in the optical needle and the spacing between adjacent segments are controllable by reversing and focusing the radiation pattern from a sectional-uniform line source antenna to the focal volume of a 4Pi focusing system. By solving the inverse problem, we can obtain the required incident field distribution at the pupil plane to create the multi-segmented optical needle. Numerical examples demonstrate that a multi-segmented optical needle with variable focal depth, adjustable interval, narrow lateral width, homogeneous intensity, and high longitudinal polarization purity can be formed using the proposed approach. The length of each needle segment is approximately equal to the length of the corresponding sectional uniform line source. The multi-segmented optical needle may be employed in applications such as multi-particle acceleration, multi-particle trapping and manipulation, laser machining, and laser material processing.
Biosensing methods for the detection of highly pathogenic avian influenza H5N1 and H7N9 viruses
Authors: Li Zhanming , Fu Yingchun , Liao Ming , Li Yanbin
Published: August 2017

A review of the biosensing methods for the detection of highly pathogenic avian influenza H5N1 and H7N9 viruses.
Unraveling the mechanism and impact of oxide production in LA-ICP-MS by comprehensive analysis of REE-Th-U phosphates
Authors: Itano Keita , Iizuka Tsuyoshi
Published: August 2017

Oxide interference can be problematic for trace element and isotopic analyses using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).
X-Ray responsive nanoparticles with triggered release of nitrite, a precursor of reactive nitrogen species, for enhanced cancer radiosensitization
Authors: Liu Fang , Lou Junzhe , Hristov Dimitre
Published: August 2017

New strategy to enhance cancer radiotherapy: A novel gold nanosystem with surface-grafted nitroimidazole and cell nucleus-targeting peptide achieves the release of a RNS precursor, nitrite, by ionizing radiation. In vitro radiotherapy shows enhanced sensitivity of hypoxic cancer cells to X-ray radiation, presumably due to the generation of both reactive oxygen and nitrogen species.
Poly-cytosine-mediated nanotags for SERS detection of Hg2+
Authors: Qi Lin , Xiao Mingshu , Wang Fei , Wang Lihua , Ji Wei , Man Tiantian , Aldalbahi Ali , Naziruddin Khan M. , Periyasami Govindasami , Rahaman Mostafizur , Alrohaili Abdulaziz , Qu Xiangmeng , Pei Hao , Wang Cheng , Li Li
Published: August 2017

We demonstrate poly-cytosine-mediated nanotags for SERS detection of Hg2+, based on T–Hg2+–T coordination and poly-cytosine-mediated Raman activity.
Living cationic ring-opening polymerization of 2-ethyl-2-oxazoline following sustainable concepts: microwave-assisted and droplet-based millifluidic processes in an ionic liquid medium
Authors: Petit C. , Grassl B. , Mignard E. , Luef K. P. , Wiesbrock F. , Reynaud S.
Published: August 2017

The synthesis of poly(2-ethyl-2-oxazoline) has been developed in an ionic liquid and performed with microwave-assisted or droplet-based millifluidic processes.
Scaling behaviour and rate-determining steps in filamentous self-assembly
Authors: Meisl Georg , Rajah Luke , Cohen Samuel A. I. , Pfammatter Manuela , Šarić Anđela , Hellstrand Erik , Buell Alexander K. , Aguzzi Adriano , Linse Sara , Vendruscolo Michele , Dobson Christopher M. , Knowles Tuomas P. J.
Published: August 2017

A general reaction network for filamentous self-assembly unifies mechanistic descriptions and links the overall scaling behaviour to the underlying rate-determining steps.
Thermal optimisation of metal hydride reactors for thermal energy storage applications
Authors: Dong D. , Humphries T. D. , Sheppard D. A. , Stansby B. , Paskevicius M. , Sofianos M. V. , Chaudhary A.-L. , Dornheim M. , Buckley C. E.
Published: August 2017

A prototype metal hydride reactor using supercritical water as a heat transfer fluid for thermal energy storage applications.
Edge‐guided with gradient‐assisted depth up‐sampling
Authors: Ren Yannan , Liu Ju , Yuan Hui , Wan Wenbo
Published: August 2017

Most of depth up‐sampling algorithms are based on the consistent hypothesis, i.e. the object boundaries in the colour image are consistent with depth discontinuity regions in the depth map. However, the hypothesis is not always correct. Under the combined guidance of high‐resolution (HR) depth edge map and HR colour image gradient map, a simple and efficient depth up‐sampler is presented. Firstly, the consistent regions are distinguished from the other regions and more accurate depth edge points are found. Then, the initial up‐sampled depth map from traditional bilinear interpolation is refined by an effective depth‐assignment scheme. Extensive experiments demonstrate that the proposed method outperforms conventional interpolation algorithms and some other edge‐based depth up‐sampling methods.
Widening and narrowing of time interval due to single‐event transients in 45 nm vernier‐type TDC
Authors: Ramaniharan Pasupathy K. , Boby Bindu
Published: August 2017

Single‐event transients (SETs) due to heavy‐ion (HI) strikes adversely affect the electronic circuits in sub‐100 nm regime in radiation environment. Time‐to‐digital converter (TDC) is an important electronic component in many fields such as space applications and is used for measuring time precisely as a digital value. In this study, the effect of SET due to radiation strike on 45 nm vernier‐type TDC with a resolution of 7 ps is analysed using cadence spectre circuit simulator. When HI strikes the delay line of TDC close to the START/STOP pulse transition, it either widens or narrows the time interval to be measured, depending on whether it strikes the top/bottom voltage‐controlled delay line (VCDL). Results show that the TDC is sensitive if the SET occurs during the transition of START/STOP pulse. Moreover, the change in the time interval occurs in a regular staircase pattern, if the VCDL is struck at all instants near the pulse transition. These errors lead to erroneous digital output and cause abrupt deviations in the staircase transfer characteristics of TDC. SETs in other constituent components of TDC such as D‐flip‐flop and priority encoder produces glitches which can be mitigated using existing guard gate technique.
LED non‐linearity mitigation techniques for optical OFDM‐based visible light communications
Authors: Sheu Jeng‐Shin , Li Bing‐Jia , Lain Jenn‐Kaie
Published: August 2017

The visible light communication (VLC) utilising the light emitting diodes (LEDs) as transmitters has gained much interest for the indoor wireless access due to its abundance of unregulated spectrum. However, the LED non‐linearities cause a detrimental non‐linear distortion especially for the adoption of optical orthogonal frequency‐division multiplexing (O‐OFDM), which is known to suffer high peak‐to‐average power ratio (PAPR). Specifically, the authors consider the direct current biased O‐OFDM (DCO‐OFDM) to realise the O‐OFDM signals. This study aims to develop the mitigation techniques for LED non‐linearities at transmitter through the combined advantages of PAPR reduction and the technique of linearising the non‐linear LED characteristics. The orthogonal cover code sequence is exploited to design a transform precoding to reduce the PAPR. An uncomplicated pre‐distorter at transmitter is adopted to linearise the LED non‐linearity. In addition, the authors propose a dynamic DC biasing method to avoid the clipping noise in DCO‐OFDM. As a whole, the proposed techniques at VLC transmitter can improve the LED non‐linearities even for large input signals.
Highly Selective Approach to α-Iodoketones from Aminoalkynols with Iodine Monochloride
Authors: Bhargava Suresh , Likhar Pravin , Rao Vijay , Mirzadeh Nedaossadat
Published: August 2017

A protocol has been developed to achieve selective and direct synthesis of α-iodoketones under mild condition, from the reaction of aminoalkynols with iodine monochloride. The scope of the reaction was investigated using various aminoalkynols with iodine monochloride and the corresponding α-iodoketones were obtained selectively without forming iodocyclized and/or addition products.
Oral Desensitization to Penicillin for the Treatment of Pregnant Women with Syphilis: A Successful Program
Authors: Dallé Jéssica , Ramos Mauro Cunha , Jimenez Mirela Foresti , Escobar Fernanda Garcia , Antonello Vicente Sperb
Published: August 2017

Gestational syphilis is a prevalent disease in Brazil and other low and medium income countries. Desensitization to penicillin is recommended for pregnant women with syphilis who are allergic to β-lactams. This is a descriptive study utilizing outpatient medical records from 2011 to 2015 from a mother and child hospital that is part of the national healthcare system in the South of Brazil, which performs an average of 3,600 birth assistances per year. All cases of pregnant women with syphilis and presumptive diagnosis of β-lactam allergy during the study period were included. The patients referred for desensitization originated from the hospital prenatal care service, as well as from municipal/state antenatal care services. Oral desensitization was performed in the obstetric emergency room, and adult and pediatric intensive care units were available at all times. Ten patients underwent desensitization during the period of study. Personal history of urticaria was the most common reaction that demanded desensitization. All patients tolerated the procedure well, and showed no adverse reactions. We report a successful program of oral desensitization. None of the patients presented adverse reactions or complications, a fact that corroborates the feasibility and safety of the desensitization protocol. Oral administration of penicillin comes at a low cost, and optimizes the use of time and resources.
Intestinal Perforation during the Stabilization Period in a Preterm Infant with Congenital Diaphragmatic Hernia
Authors: Straňák Zbyněk , Pýcha Karel , Feyereislova Simona , Feyereisl Jaroslav , Rygl Michal
Published: August 2017

Background Delayed surgery after stabilization of infants with congenital diaphragmatic hernia (CDH) is an accepted strategy. However, the evidence favoring delayed versus immediate surgical repair is limited. We present an extremely rare case of a very low-birth-weight infant with prenatally diagnosed left-sided CDH and unexpected transmural bowel perforations developing within the postnatal stabilization period.

Case Report A neonate born at 31st week of gestation with a birth weight of 1,470 g with antenatally diagnosed left-sided CDH presented with bowel dilation leading to transmural bowel perforations on the 2nd day of life. Meconium pleuroperitonitis resulted in severe systemic inflammatory response syndrome, pulmonary hypertension, multiple organ failure, and death.

Conclusion In neonates with CDH deteriorating under standard postnatal management, intestinal perforation, and early surgical intervention should be considered.
Die Gesundheitssysteme im nachkolonialen Afrika als Spiegel der sozialpolitischen Situation
Authors: Bofinger F.
Published: August 2017

Die ärztliche Tätigkeit in Subsahara-Afrika ist eine tropenmedizinische Herausforderung und stellt erhöhte Ansprüche an die physischen und psychischen Fähigkeiten des Teams. Dazu gehören auch Kenntnisse über die politischen, ökonomischen und gesellschaftlichen Verhältnisse dieses Kontinents, besonders vor dem Hintergrund der kolonialen Vergangenheit der europäischen Mächte in Afrika.

Angesichts der Statistiken zu Krankheit, Tod und unzureichender Patientenversorgung in Afrika bekommen Fragen zum Gesundheitswesen zwangsläufig politische Dimensionen.

Ein kurzer Abriss über die Geschichte und die sozioökonomischen Zustände in Subsahara-Afrika soll diese Zusammenhänge erläutern.
Evaluating the Multitarget Effects of Combinations through Multistep Clustering of Pharmacological Data: the Example of the Commercial Preparation Iberogast
Authors: Abdel-Aziz Heba , Kelber Olaf , Lorkowski Gerhard , Storr Martin
Published: August 2017

Herbal combination preparations are widely used in traditional herbal medicine and are even established as modern evidence-based herbal medicinal products. The rationale behind such combinations is often questioned and assessing the contribution of each of the combination partners to overall activity is challenging. STW 5 (Iberogast) is such a combination with confirmed clinical efficacy in functional gastrointestinal disorders. It consists of nine plant extracts responsible for its multitarget function in these multifactorial diseases with their heterogeneous and overlapping pathomechanisms. This makes the combination an ideal candidate for the use of the newly described method of stepwise cluster analysis, a standardized procedure to transfer heterogeneous pharmacological data, from different models, into effect size categories. This allows for a stepwise cluster formation starting from the level of single tests up to the level of different pathomechanisms involved in the development of a certain disease, in this case functional dyspepsia subtypes and irritable bowel syndrome. In the current article, an overview on the pharmacological data on STW 5 and its single components is provided. The data are further analyzed using stepwise cluster formation, resulting in a summary of the different modes of action of STW 5 along with an evaluation of the contribution of the single constituents to the overall multitarget effects of the herbal combination preparation.
Acute Abdomen Syndrome Due To Spontaneous Intraperitoneal Bladder Rupture Following Vaginal Delivery
Authors: Habek Dubravko , Marton Ingrid , Luetic Ana , Prka Matija , Kuljak Zeljka , Živković Krešimir , Cenkovčan Mario , Mazuran Berislav
Published: August 2017

We report a rare case of spontaneous intraperitoneal bladder rupture following normal vaginal delivery without concomitant uterine rupture. Key diagnostic clinical features were acute renal failure, new-onset ascites and bowel ileus with urosepsis. Laparotomy and bladder repair with omentum patch were performed with no adverse outcome reported.
Microscopic origin of wall slip during flow of an entangled DNA solution in microfluidics: Flow induced chain stretching versus chain desorption
Authors: Hemminger Orin , Boukany Pouyan E.
Published: August 2017

Despite the relevance and importance of slip, a fundamental understanding of the underlying molecular mechanisms of wall slip in polymer flow is still missing. In this work, we investigate the slip behavior of an entangled DNA solution at a molecular scale using a confocal microscope coupled to a microfluidic device. From microscopic measurement, we obtain both the velocity profile and conformation of polymeric chains by visualizing DNA molecules during flow on various surfaces (ranging from weak to strong interactions with DNA molecules). In channel flow at a low Weissenberg number (Wi = 0.14), we observe a parabolic flow for an APTES-treated glass (with strong interaction with DNA) in the absence of slip, while a significant amount of slip has been observed for a regular glass (with a weak interaction with DNA). At higher flow rates (Wi > 1.0), strong slip appears during flow on APTES-treated surfaces. In this case, only immobile DNA molecules are stretched on the surface and other bulk chains remain coiled. This observation suggests that the flow induced chain stretching at the interface is the main mechanism of slip during flow on strong surfaces. Conversely, for slip flow on surfaces with weak interactions (such as unmodified or acrylate-modified glasses), polymeric chains are desorbed from the surface and a thin layer of water is present near the surface, which induces an effective slip during flow. By imaging DNA conformations during both channel and shear flows on different surfaces, we elucidate that either chain desorption or flow-induced stretching of adsorbed chains occurs depending on the surface condition. In general, we expect that these new insights into the slip phenomenon will be useful for studying the biological flow involving single DNA molecule experiments in micro/nanofluidic devices.
Enhanced switching stability in Ta2O5 resistive RAM by fluorine doping
Authors: Sedghi N. , Li H. , Brunell I. F. , Dawson K. , Guo Y. , Potter R. J. , Gibbon J. T. , Dhanak V. R. , Zhang W. D. , Zhang J. F. , Hall S. , Robertson J. , Chalker P. R.
Published: August 2017

The effect of fluorine doping on the switching stability of Ta2O5 resistive random access memory devices is investigated. It shows that the dopant serves to increase the memory window and improve the stability of the resistive states due to the neutralization of oxygen vacancies. The ability to alter the current in the low resistance state with set current compliance coupled with large memory window makes multilevel cell switching more favorable. The devices have set and reset voltages of <1 V with improved stability due to the fluorine doping. Density functional modeling shows that the incorporation of fluorine dopant atoms at the two-fold O vacancy site in the oxide network removes the defect state in the mid bandgap, lowering the overall density of defects capable of forming conductive filaments. This reduces the probability of forming alternative conducting paths and hence improves the current stability in the low resistance states. The doped devices exhibit more stable resistive states in both dc and pulsed set and reset cycles. The retention failure time is estimated to be a minimum of 2 years for F-doped devices measured by temperature accelerated and stress voltage accelerated retention failure methods.
Impact of tungsten doping on the dynamics of the photo-induced insulator-metal phase transition in VO2 thin film investigated by optical pump-terahertz probe spectroscopy
Authors: Émond Nicolas , Ibrahim Akram , Torriss Badr , Hendaoui Ali , Al-Naib Ibraheem , Ozaki Tsuneyuki , Chaker Mohamed
Published: August 2017

The influence of tungsten (W) doping on the ultrafast dynamics of the photo-induced insulator-metal phase transition (IMT) is investigated at room temperature in epitaxially grown vanadium dioxide (VO2) thin films by means of optical pump-terahertz (THz) probe spectroscopy. It is observed that the THz transmission variation of the films across the IMT follows a bi-exponential decrease characterized by two time constants, one corresponding to a fast process and the other to a slower process. W-doping (i) reduces the photo-excitation fluence threshold required for triggering the IMT, (ii) accelerates the slow process, and (iii) increases the THz transient transmission variation for corresponding fluences. From the Drude-Smith model, it is deduced that a strong carrier confinement and an enhancement of the transient conductivity occur across the IMT. The IMT is also accompanied by an increase in the carrier concentration in the films, which is enhanced by W-doping. Our results suggest that W-doped VO2 could be advantageously exploited in applications such as ultrafast THz optical switching and modulation devices.
Geometrical factors in propagation block and spiral wave initiation
Authors: Zykov Vladimir , Krekhov Alexei , Bodenschatz Eberhard
Published: August 2017

Many theoretical and experimental studies indicate that a propagation block represents an important factor in spiral wave initiation in excitable media. The analytical and numerical results we obtained for a generic two-component reaction-diffusion system demonstrate quantitative conditions for the propagation block in a one-dimensional and a two-dimensional medium due to a sharp spatial increase of the medium's excitability or the coupling strength above a certain critical value. Here, we prove that this critical value strongly depends on the medium parameters and the geometry of the inhomogeneity. For an exemplary two-dimensional medium, we show how the propagation block can be used to initiate spiral waves by a specific choice of the size and shape of the medium's inhomogeneity.
Theoretical investigation of intersystem crossing in the cyanonitrene molecule, 1NCN → 3NCN
Authors: Pfeifle Mark , Georgievskii Yuri , Jasper Ahren W. , Klippenstein Stephen J.
Published: August 2017

The NCN diradical is an important intermediate of prompt nitric oxide formation in flames. The mechanism of intersystem crossing (ISC) in the NCN molecule formed via pyrolysis or photolysis of NCN3 is of relevance to the interpretation of experiments that utilize NCN3 as a precursor for laboratory studies of NCN kinetics. This mechanism has been investigated by means of multi-reference configuration interaction calculations. From the potential energy surfaces for NCN3 dissociation, it was inferred that both thermal and photo-chemical decomposition initially lead to NCN in its lowest singlet state, ã1Δg, with a possible contribution from the b̃1Σg+ state at low photolysis wavelengths. Direct formation of the triplet ground state X̃ 3Σg− is also feasible for the photolytic pathway. An analysis of surface crossings between ã or b̃ and the triplet ground state X̃ 3Σg− in the absence and presence of a helium atom revealed an ISC channel NCN1(ã)→3NCN(X̃) via a strongly bent structure. However, its barrier of 38 kcal mol−1 relative to the singlet minimum turned out to be much too high to explain the fast ISC observed in experiments. A rigid-bender model including Renner-Teller interactions was used to examine the occurrence of mixed-multiplicity rovibrational states—so-called gateway states—that could enhance collision-induced ISC. The results of this study indicate that a gateway mechanism is probably not operative in the case of the ã/X̃ pair of states in NCN.
Terahertz induced optical birefringence in polar and nonpolar liquids
Authors: Bodrov Sergey , Sergeev Yury , Murzanev Aleksey , Stepanov Andrey
Published: August 2017

The terahertz induced optical birefringence in liquids with polar (acetone, chloroform) and nonpolar (benzene, carbon tetrachloride) molecules has been investigated. Fast and slow responses were extracted from the experimental data and compared with previous studies of the femtosecond optical Kerr effect. Terahertz Kerr constants were found and compared with known DC and optical constants. Analysis of the results obtained showed that, in contrast to the optical excitation, the interaction of a permanent dipole moment of molecules with a THz field makes a significant contribution to the transient birefringence and Kerr constants. This conclusion fully agrees with the direct comparison of the femtosecond optical and THz Kerr effects reported by Sajadi et al. [Nat. Commun. 8, 14963 (2017)].