bluuebunny/crossref_metadata_2025 huggingface dataset:
Localized Spoof Surface Plasmons based on Closed Subwavelength High Contrast Gratings: Concept and Microwave-Regime Realizations
Authors: Li Zhuo , Xu Bingzheng , Liu Liangliang , Xu Jia , Chen Chen , Gu Changqing , Zhou Yongjin
Published: June 2016

In this work, we report the existence of spoof localized surface plasmons (spoof-LSPs) arising with closed high contrast gratings (HCGs) at deep subwavelength scales, another platform for field localization at microwave frequencies. The HCGs are in the form of a periodic array of radial dielectric blocks with high permittivity around a metal core supporting spoof-LSPs of transverse magnetic (TM) form. Simulation results validate the phenomenon and a metamaterial approach is also given to capture all the resonant features of this kind of spoof-LSPs. In addition, experimental verification of the existence of spoof-LSPs supported by a three dimensional (3D) HCGs resonance structure in the microwave regime is presented. This work expands the original spoof-LSPs theory and opens up a new avenue for obtaining resonance devices in the microwave frequencies.
Functional analysis of thioredoxin from the desert lichen-forming fungus, Endocarpon pusillum Hedwig, reveals its role in stress tolerance
Authors: Li Hui , Wei Jiang-Chun
Published: June 2016

Endocarpon pusillum is a lichen-forming fungus with an outstanding stress resistance property closely related to its antioxidant system. In this study, thioredoxin (Trx), one of the main components of antioxidant defense systems in E. pusillum (EpTrx), was characterized and analyzed both in transgenic yeasts and in vitro. Our analyses identified that the heterologous expression of EpTrx in the yeast Pichia pastoris significantly enhanced its resistance to osmotic and oxidative stresses. Assays in vitro showed EpTrx acted as a disulfide reductase as well as a molecular chaperone by assembling into various polymeric structures. Upon exposure to heat-shock stress, EpTrx exhibited weaker disulfide reductase activity but stronger chaperone activity, which coincided with the switching of the protein complexes from low molecular weight forms to high molecular weight complexes. Specifically, we found that Cys31 near but not at the active site was crucial in promoting the structural and functional transitions, most likely by accelerating the formation of intermolecular disulfide bond. Transgenic Saccharomyces cerevisiae harboring the native EpTrx exhibited stronger tolerance to oxidative, osmotic and high temperature stresses than the corresponding yeast strain containing the mutant EpTrx (C31S). Our results provide the first molecular evidence on how Trx influences stress response in lichen-forming fungi.
Gomafu lncRNA knockout mice exhibit mild hyperactivity with enhanced responsiveness to the psychostimulant methamphetamine
Authors: Ip Joanna Y. , Sone Masamitsu , Nashiki Chieko , Pan Qun , Kitaichi Kiyoyuki , Yanaka Kaori , Abe Takaya , Takao Keizo , Miyakawa Tsuyoshi , Blencowe Benjamin J. , Nakagawa Shinichi
Published: June 2016

The long noncoding RNA Gomafu/MIAT/Rncr2 is thought to function in retinal cell specification, stem cell differentiation and the control of alternative splicing. To further investigate physiological functions of Gomafu, we created mouse knockout (KO) model that completely lacks the Gomafu gene. The KO mice did not exhibit any developmental deficits. However, behavioral tests revealed that the KO mice are hyperactive. This hyperactive behavior was enhanced when the KO mice were treated with the psychostimulant methamphetamine, which was associated with an increase in dopamine release in the nucleus accumbens. RNA sequencing analyses identified a small number of genes affected by the deficiency of Gomafu, a subset of which are known to have important neurobiological functions. These observations suggest that Gomafu modifies mouse behavior thorough a mild modulation of gene expression and/or alternative splicing of target genes.
A Lipid Based Antigen Delivery System Efficiently Facilitates MHC Class-I Antigen Presentation in Dendritic Cells to Stimulate CD8+ T Cells
Authors: Maji Mithun , Mazumder Saumyabrata , Bhattacharya Souparno , Choudhury Somsubhra Thakur , Sabur Abdus , Shadab Md. , Bhattacharya Pradyot , Ali Nahid
Published: June 2016

The most effective strategy for protection against intracellular infections such as Leishmania is vaccination with live parasites. Use of recombinant proteins avoids the risks associated with live vaccines. However, due to low immunogenicity, they fail to trigger T cell responses particularly of CD8+ cells requisite for persistent immunity. Previously we showed the importance of protein entrapment in cationic liposomes and MPL as adjuvant for elicitation of CD4+ and CD8+ T cell responses for long-term protection. In this study we investigated the role of cationic liposomes on maturation and antigen presentation capacity of dendritic cells (DCs). We observed that cationic liposomes were taken up very efficiently by DCs and transported to different cellular sites. DCs activated with liposomal rgp63 led to efficient presentation of antigen to specific CD4+ and CD8+ T cells. Furthermore, lymphoid CD8+ T cells from liposomal rgp63 immunized mice demonstrated better proliferative ability when co-cultured ex vivo with stimulated DCs. Addition of MPL to vaccine enhanced the antigen presentation by DCs and induced more efficient antigen specific CD8+ T cell responses when compared to free and liposomal antigen. These liposomal formulations presented to CD8+ T cells through TAP-dependent MHC-I pathway offer new possibilities for a safe subunit vaccine.
Annexin A5 is the Most Abundant Membrane-Associated Protein in Stereocilia but is Dispensable for Hair-Bundle Development and Function
Authors: Krey Jocelyn F. , Drummond Meghan , Foster Sarah , Porsov Edward , Vijayakumar Sarath , Choi Dongseok , Friderici Karen , Jones Sherri M. , Nuttall Alfred L. , Barr-Gillespie Peter G.
Published: June 2016

The phospholipid- and Ca2+-binding protein annexin A5 (ANXA5) is the most abundant membrane-associated protein of ~P23 mouse vestibular hair bundles, the inner ear’s sensory organelle. Using quantitative mass spectrometry, we estimated that ANXA5 accounts for ~15,000 copies per stereocilium, or ~2% of the total protein there. Although seven other annexin genes are expressed in mouse utricles, mass spectrometry showed that none were present at levels near ANXA5 in bundles and none were upregulated in stereocilia ofAnxa5−/−mice. Annexins have been proposed to mediate Ca2+-dependent repair of membrane lesions, which could be part of the repair mechanism in hair cells after noise damage. Nevertheless, matureAnxa5−/−mice not only have normal hearing and balance function, but following noise exposure, they are identical to wild-type mice in their temporary or permanent changes in hearing sensitivity. We suggest that despite the unusually high levels of ANXA5 in bundles, it does not play a role in the bundle’s key function, mechanotransduction, at least until after two months of age in the cochlea and six months of age in the vestibular system. These results reinforce the lack of correlation between abundance of a protein in a specific compartment or cellular structure and its functional significance.
Interface induce growth of intermediate layer for bandgap engineering insights into photoelectrochemical water splitting
Authors: Zhang Jian , Zhang Qiaoxia , Wang Lianhui , Li Xing’ao , Huang Wei
Published: June 2016

A model of interface induction for interlayer growing is proposed for bandgap engineering insights into photocatalysis. In the interface of CdS/ZnS core/shell nanorods, a lamellar solid solution intermediate with uniform thickness and high crystallinity was formed under interface induction process. Merged the novel charge carrier transfer layer, the photocurrent of the core/shell/shell nanorod (css-NR) array was significantly improved to 14.0 mA cm−2 at 0.0 V vs. SCE, nearly 8 times higher than that of the perfect CdS counterpart and incident photon to electron conversion efficiency (IPCE) values above 50% under AM 1.5G irradiation. In addition, this array photoelectrode showed excellent photocatalytic stability over 6000 s. These results suggest that the CdS/Zn1−xCdxS/ZnS css-NR array photoelectrode provides a scalable charge carrier transfer channel, as well as durability and therefore is promising to be a large-area nanostructured CdS-based photoanodes in photoelectrochemical (PEC) water splitting system.
Prevalence and correlates of valvular heart diseases in the elderly population in Hubei, China
Authors: Shu Chang , Chen Si , Qin Tingting , Fu Zhen , Sun Tucheng , Xie Mingxing , Zhang Li , Dong Nianguo , Yin Ping
Published: June 2016

We sought to determine the prevalence and correlates of valvular heart diseases (VHD) in the elderly population. The participants’ personal information, medical history, behavioral habits and clinical status were assessed by questionnaire, while the left ventricular dimensions, function and the presence and severity of VHD were evaluated by transthoracic echocardiography. This study analyzed the data of 3948 participants who were older than 60 years. Significant VHD was present in 1.93% of participants; the standardized prevalence of VHD among the elderly population in Hubei was 2.05% (95% CI: 1.61–2.49). The most frequent VHD was aortic regurgitation, followed by tricuspid regurgitation, mitral regurgitation and multiple valve diseases. Univariate analysis results indicated that compared with participants without VHD, those with VHD were older (p < 0.001), with a higher body mass index (BMI) (p < 0.001), were more likely to smoke (p = 0.04) and had higher rates of coronary artery disease (CAD) (p < 0.001) and arrhythmia (p < 0.001). The results of multinomial regression analysis of complex sampling indicated that combined mitral and aortic valve diseases were related to older age, male sex and smoking; CAD was associated with single left-sided VHD.
The rise of angiosperm-dominated herbaceous floras: Insights from Ranunculaceae
Authors: Wang Wei , Lin Li , Xiang Xiao-Guo , Ortiz Rosa del C. , Liu Yang , Xiang Kun-Li , Yu Sheng-Xiang , Xing Yao-Wu , Chen Zhi-Duan
Published: June 2016

The rise of angiosperms has been regarded as a trigger for the Cretaceous revolution of terrestrial ecosystems. However, the timeframe of the rise angiosperm-dominated herbaceous floras (ADHFs) is lacking. Here, we used the buttercup family (Ranunculaceae) as a proxy to provide insights into the rise of ADHFs. An integration of phylogenetic, molecular dating, ancestral state inferring and diversification analytical methods was used to infer the early evolutionary history of Ranunculaceae. We found that Ranunculaceae became differentiated in forests between about 108–90 Ma. Diversification rates markedly elevated during the Campanian, mainly resulted from the rapid divergence of the non-forest lineages, but did not change across the Cretaceous-Paleogene boundary. Our data for Ranunculaceae indicate that forest-dwelling ADHFs may have appeared almost simultaneously with angiosperm-dominated forests during the mid-Cretaceous, whereas non-forest ADHFs arose later, by the end of the Cretaceous terrestrial revolution. Furthermore, ADHFs were relatively unaffected by the Cretaceous-Paleogene mass extinction.
Hormetic Effect of Chronic Hypergravity in a Mouse Model of Allergic Asthma and Rhinitis
Authors: Jang Tae Young , Jung Ah-Yeoun , Kim Young Hyo
Published: June 2016

We aimed to evaluate the effect of chronic hypergravity in a mouse model of allergic asthma and rhinitis. Forty BALB/c mice were divided as: group A (n = 10, control) sensitized and challenged with saline, group B (n = 10, asthma) challenged by intraperitoneal and intranasal ovalbumin (OVA) to induce allergic asthma and rhinitis, and groups C (n = 10, asthma/rotatory control) and D (n = 10, asthma/hypergravity) exposed to 4 weeks of rotation with normogravity (1G) or hypergravity (5G) during induction of asthma/rhinitis. Group D showed significantly decreased eosinophils, neutrophils, and lymphocytes in their BAL fluid compared with groups B and C (p < 0.05). In real-time polymerase chain reaction using lung homogenate, the expression of IL-1β was significantly upregulated (p < 0.001) and IL-4 and IL-10 significantly downregulated (p < 0.05) in group D. Infiltration of inflammatory cells into lung parenchyma and turbinate, and the thickness of respiratory epithelium was significantly reduced in group D (p < 0.05). The expression of Bcl-2 and heme oxygenase-1 were significantly downregulated, Bax and extracellular dismutase significantly upregulated in Group D. Therefore, chronic hypergravity could have a hormetic effect for allergic asthma and rhinitis via regulation of genes involved in antioxidative and proapoptotic pathways. It is possible that we could use hypergravity machinery for treating allergic respiratory disorders.
A Schisandra-Derived Compound Schizandronic Acid Inhibits Entry of Pan-HCV Genotypes into Human Hepatocytes
Authors: Qian Xi-Jing , Zhang Xiao-Lian , Zhao Ping , Jin Yong-Sheng , Chen Hai-Sheng , Xu Qing-Qiang , Ren Hao , Zhu Shi-Ying , Tang Hai-Lin , Zhu Yong-Zhe , Qi Zhong-Tian
Published: June 2016

Despite recent progress in the development of hepatitis C virus (HCV) inhibitors, cost-effective antiviral drugs, especially among the patients receiving liver transplantations, are still awaited. Schisandra is a traditional medicinal herb used to treat a range of liver disorders including hepatitis for thousands of years in China. To isolate the bioactive compounds of schisandra for the treatment of HCV infection, we screened a schisandra-extracts library and identified a tetracyclic triterpenoid, schizandronic acid (SZA), as a novel HCV entry inhibitor. Our findings suggested that SZA potently inhibited pan-HCV genotype entry into hepatoma cells and primary human hepatocytes without interfering virus binding on cell surface or internalization. However, virion-cell fusion process was impaired in the presence of SZA, along with the increased host membrane fluidity. We also found that SZA inhibited the spread of HCV to the neighboring cells, and combinations of SZA with interferon or telaprevir resulted in additive synergistic effect against HCV. Additionally, SZA diminished the establishment of HCV infection in vivo. The SZA target is different from conventional direct-acting antiviral agents, therefore, SZA is a potential therapeutic compound for the development of effective HCV entry inhibitors, especially for patients who need to prevent HCV reinfection during the course of liver transplantations.
Size-confined fixed-composition and composition-dependent engineered band gap alloying induces different internal structures in L-cysteine-capped alloyed quaternary CdZnTeS quantum dots
Authors: Adegoke Oluwasesan , Park Enoch Y.
Published: June 2016

The development of alloyed quantum dot (QD) nanocrystals with attractive optical properties for a wide array of chemical and biological applications is a growing research field. In this work, size-tunable engineered band gap composition-dependent alloying and fixed-composition alloying were employed to fabricate new L-cysteine-capped alloyed quaternary CdZnTeS QDs exhibiting different internal structures. Lattice parameters simulated based on powder X-ray diffraction (PXRD) revealed the internal structure of the composition-dependent alloyed CdxZnyTeS QDs to have a gradient nature, whereas the fixed-composition alloyed QDs exhibited a homogenous internal structure. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis confirmed the size-confined nature and monodispersity of the alloyed nanocrystals. The zeta potential values were within the accepted range of colloidal stability. Circular dichroism (CD) analysis showed that the surface-capped L-cysteine ligand induced electronic and conformational chiroptical changes in the alloyed nanocrystals. The photoluminescence (PL) quantum yield (QY) values of the gradient alloyed QDs were 27–61%, whereas for the homogenous alloyed QDs, the PL QY values were spectacularly high (72–93%). Our work demonstrates that engineered fixed alloying produces homogenous QD nanocrystals with higher PL QY than composition-dependent alloying.
Dengue Specific Immunoglobulin A Antibody is Present in Urine and Associated with Disease Severity
Authors: Zhao Hui , Qiu Shuang , Hong Wen-Xin , Song Ke-Yu , Wang Jian , Yang Hui-Qin , Deng Yong-Qiang , Zhu Shun-Ya , Zhang Fu-Chun , Qin Cheng-Feng
Published: June 2016

The kinetics of dengue virus (DENV)-specific IgA antibody in urine and the potential correlation with disease severity remain elusive. In this study, 262 serial urine samples from 78 laboratory-confirmed patients were assayed by a commercial immunoglobulin A (IgA) kit against DENV. All cases were classified into dengue fever (DF) and severe dengue (SD) according to the 2009 WHO/TDR guideline. The total positive rate of IgA in urine was 59%. DENV-specific IgA was detected in urine from day 2 to day 13 after the onset of illness in DF patients; While for SD patients, anti-DENV IgA could be detected till day 14. The positive rate of IgA in patients with secondary infection was higher than that in patients with primary infection. Importantly, during 4–7 days after the onset of illness, the IgA positive rate of SD patients was significantly higher than that of DF patients. Especially, the intensity of IgA signal in SD patients was obviously stronger than that in DF patient at the recovery stage. Overall, our results suggested that the existence of DENV-specific IgA antibodies in urine might be a warning sign for the severity of disease and its measurement might provide valuable guidance for proper patient management.
Role of freeze-thaw cycles and chlorpyrifos insecticide use on diffuse Cd loss and sediment accumulation
Authors: Wang Fangli , Ouyang Wei , Hao Fanghua , Jiao Wei , Shan Yushu , Lin Chunye
Published: June 2016

Freeze-thaw cycles are predicted to increase in cold temperate regions. The potential influence of the interactions of freeze-thaw cycles and agrochemicals on the release of Cd into river water is unknown. In this study, the interactions of freeze-thaw cycles and chlorpyrifos (FC) on Cd mobility in soils were analysed. The spatial variability of soil Cd under long-term intensive tillage in a freeze-thaw agro-system was also identified. The temporal variation of sediment Cd was detected based on analysis of the sediment geochemistry. The results showed that FC increased soil Cd mobility, with an increase of approximately 10% in CaCl2-extractable Cd. The increased mobile fractions of water-soluble and exchangeable Cd originated from the decreased fraction of Fe-Mn-oxide-associated Cd and organic matter-bound Cd. The total Cd content in the surface soil followed the zonally decreasing trend of dry land > paddy land > natural land. The Cd concentrations and sedimentation rates of the sediment core generally increased from 1943 to 2013 due to agricultural exploration and farmland irrigation system construction, indicating an increase of the Cd input flux into water. The results provide valuable information about the soil Cd transport response to the influence of climatic and anthropogenic factors in cold intensive agro-systems.
Role of Histidine 547 of Human Dopamine Transporter in Molecular Interaction with HIV-1 Tat and Dopamine Uptake
Authors: Yuan Yaxia , Quizon Pamela M. , Sun Wei-Lun , Yao Jianzhuang , Zhu Jun , Zhan Chang-Guo
Published: June 2016

HIV-1 Tat plays an important role in HIV-associated neurocognitive disorders (HAND) by disrupting neurotransmission including dopamine uptake by human dopamine transporter (hDAT). Previous studies have demonstrated that HIV-1 Tat directly binds to hDAT and some amino-acid mutations that attenuate the hDAT-Tat binding also significantly decreased dopamine uptake activity of hDAT. This combined computational-experimental study demonstrates that histidine-547 (H547) of hDAT plays a crucial role in the hDAT-Tat binding and dopamine uptake by hDAT, and that the H547A mutation can not only considerably attenuate Tat-induced inhibition of dopamine uptake, but also significantly increase the Vmax of hDAT for dopamine uptake. The finding of such an unusual hDAT mutant capable of both increasing the Vmax of hDAT for dopamine uptake and disrupting the hDAT-Tat binding may provide an exciting knowledge basis for development of novel concepts for therapeutic treatment of the HAND.
Radiographic, antibacterial and bond-strength effects of radiopaque caries tagging
Authors: Umwali Aurore , Askar Haitham , Paris Sebastian , Schwendicke Falk
Published: June 2016

Selectively excavated carious lesions remain radiographically detectable. Radiopaque tagging could resolve the resulting diagnostic uncertainty. We aimed to evaluate if tagging depends on lesions depths, is antibacterial, or affects dentin bond-strengths. Artificial lesions (depth-range: 152–682 μm, n = 34/group) were induced in human dentin samples, evaluated using wavelength-independent microradiography, treated with one of two tagging materials (70% SnCl2, 30% SnF2) and re-evaluated. To evaluate antimicrobial effects, 40 dentin samples were submitted to a Lactobacillus rhamnosus invasion-model. Infected samples were treated with placebo, 0.2% chlorhexidine, SnCl2, SnF2 (n = 10/group). Dentin was sampled and colony-forming units/mg determined. Micro-tensile bond-strengths of adhesive restorations (OptiBond FL, Filtek Z250) to tagged or untagged, sound and carious dentin were assessed (n = 12/group). Tagged surfaces were evaluated microscopically and via energy-dispersive X-ray-spectroscopy (EDS). Tagging effects of both materials decreased with increasing lesion depths (p < 0.001). Un-/chlorhexidine-treated dentin contained significantly more viable bacteria (median 7.3/3.7 × 105 CFU/mg) than tagged dentin (no CFU detectable, p < 0.001). Tagging decreased bond strengths (p < 0.001) on sound (−22%/−33% for SnCl2/SnF2) and carious dentin (−50%/−54%). This might be due to widespread tin chloride or fluoride precipitation, as detected via microscopy and EDS. While radiopaque tagging seems beneficial, an optimized application protocol needs to be developed prior clinical use.
Transition dipole moment orientation in films of solution processed fluorescent oligomers: investigating the influence of molecular anisotropy
Authors: Senes Alessia , Meskers Stefan C. J. , Dijkstra Wijnand M. , van Franeker Jacobus J. , Altazin Stéphane , Wilson Joanne S. , Janssen René. A. J.
Published: June 2016

The transition dipole moments of long fluorescent oligomers in a solution processed host align with the plane of the film when aggregated.
Secondary electrospray ionization coupled to high-resolution mass spectrometry reveals tryptophan pathway metabolites in exhaled human breath
Authors: García-Gómez Diego , Gaisl Thomas , Bregy Lukas , Martínez-Lozano Sinues Pablo , Kohler Malcolm , Zenobi Renato
Published: June 2016

A real-time non-invasive breath analysis technique (secondary ESI-HRMS) reveals the hitherto unknown occurrence of tryptophan pathway metabolites in breath.
High-pressure synthesis of L10 MnAl with near-stoichiometric composition
Authors: Kinemuchi Y. , Fujita A. , Ozaki K.
Published: June 2016

L10 MnAl, which is a nonequilibrium ferromagnetic phase, is fabricated successfully with various compositions via high-pressure synthesis.
Tris(pentafluorophenyl)borane as an efficient catalyst in the guanylation reaction of amines
Authors: Antiñolo Antonio , Carrillo-Hermosilla Fernando , Fernández-Galán Rafael , Martínez-Ferrer Jaime , Alonso-Moreno Carlos , Bravo Iván , Moreno-Blázquez Sonia , Salgado Manuel , Villaseñor Elena , Albaladejo José
Published: June 2016

Tris(pentafluorophenyl)borane catalyzes the reaction of guanylation of amines. Guanidine–borane adducts with FLP behavior have been described.
Ammonium and phosphate enrichment across the dry–wet transition and their ecological relevance in a subtropical reservoir, China
Authors: Mo Qiongli , Chen Nengwang , Zhou Xingpeng , Chen Jixin , Duan Shuiwang
Published: June 2016

Small river reservoirs are widespread and can be ecologically sensitive across the dry–wet transition under monsoon climate with respect to nutrient loading and phenology.
Chronic exposure to triclosan sustains microbial community shifts and alters antibiotic resistance gene levels in anaerobic digesters
Authors: Carey Daniel E. , Zitomer Daniel H. , Kappell Anthony D. , Choi Melinda J. , Hristova Krassimira R. , McNamara Patrick J.
Published: June 2016

At environmentally relevant levels triclosan caused an increase inmexB, but had no impact onintI1.
The impact of carbon nanotubes on bioaccumulation and translocation of phenanthrene, 3-CH3-phenanthrene and 9-NO2-phenanthrene in maize (Zea mays) seedlings
Authors: Wang Xilong , Liu Ye , Zhang Haiyun , Shen Xiaofang , Cai Fei , Zhang Meng , Gao Qian , Chen Weixiao , Wang Bin , Tao Shu
Published: June 2016

Carbon nanotubes greatly influence bioaccumulation and translocation of organic chemicals in maize seedlings in both single- and multiple compound systems.
High yield 5-(hydroxymethyl)furfural production from biomass sugars under facile reaction conditions: a hybrid enzyme- and chemo-catalytic technology
Authors: Alipour Siamak
Published: June 2016

An enzyme-catalytic process is introduced for high yield 5-(hydroxymethyl)furfural production from glucose in biomass hydrolysates.
Portable visual quantitative detection of aflatoxin B1using a target-responsive hydrogel and a distance-readout microfluidic chip
Authors: Ma Yanli , Mao Yu , Huang Di , He Zhe , Yan Jinmao , Tian Tian , Shi Yuanzhi , Song Yanling , Li Xingrui , Zhu Zhi , Zhou Leiji , Yang Chaoyong James
Published: June 2016

A distance-readout microfluidic chip was combined with an AFB1-responsive hydrogel for rapid, portable, selective, and quantitative detection of AFB1in real samples.
Mechanochemical functionalization of disulfide linked hydrogels
Authors: Lee Junmin , Silberstein Meredith N. , Abdeen Amr A. , Kim Sang Yup , Kilian Kristopher A.
Published: June 2016

Poly(ethylene glycol) hydrogels with disulfide linkages are functionalized through applied force.
Insight into the SEA amide thioester equilibrium. Application to the synthesis of thioesters at neutral pH
Authors: Pira S. L. , El Mahdi O. , Raibaut L. , Drobecq H. , Dheur J. , Boll E. , Melnyk O.
Published: June 2016

Peptide alkylthioesters can be prepared at neutral pH by bis(2-sulfanylethyl)amide-thiol exchange.
Design of PNIPAAM covalently grafted on halloysite nanotubes as a support for metal-based catalysts
Authors: Massaro M. , Schembri V. , Campisciano V. , Cavallaro G. , Lazzara G. , Milioto S. , Noto R. , Parisi F. , Riela S.
Published: June 2016

A thermo-responsive polymer (PNIPAAM) was covalently grafted on the external surface of halloysite nanotubes and used as support for palladium nanoparticles for application as catalyst in Suzuki cross coupling in water under microwave irradiation.
Facile and eco-friendly synthesis of chromeno[4,3-b]pyrrol-4(1H)-one derivatives applying magnetically recoverable nano crystalline CuFe2O4involving a domino three-component reaction in aqueous media
Authors: Saha Moumita , Pradhan Koyel , Das Asish R.
Published: June 2016

Nanocrystalline CuFe2O4catalyzed one pot three component synthesis of chromeno[4,3-b]pyrrol-4(1H)-one derivatives has been achieved in aqueous media.
Nanoformulations of anticancer thiosemicarbazones to reduce methemoglobin formation and improve anticancer activity
Authors: Fischer Britta , Kryeziu Kushtrim , Kallus Sebastian , Heffeter Petra , Berger Walter , Kowol Christian R. , Keppler Bernhard K.
Published: June 2016

Triapine and two derivatives were encapsulated into polymeric nanoparticles as well as liposomes. The most stable formulation showed strongly reduced methemoglobin formation and improved anticancer activity.
An alumina-coated, egg-shell Pd/α-Al2O3@SiC catalyst with enhanced ethylene selectivity in the selective hydrogenation of acetylene
Authors: Zhang Huoli , Cao Jianliang , Wu Baojun , Dai Wei , Chen Zehua , Ma Mingjie
Published: June 2016

The Pd–Ag/α-Al2O3@SiC catalyst showed higher ethylene selectivity than a Pd–Ag/α-Al2O3 catalyst when achieving complete removal of acetylene in an ethylene-rich stream.
Thermoelectric properties and high-temperature stability of the Ti1−xVxCoSb1−xSnx half-Heusler alloys
Authors: Asaad M. , Buckman J. , Smith R. I. , Bos J. W. G.
Published: June 2016

The thermoelectric properties and high-temperature stability of the Ti1−xVxCoSb1−xSnx solid solution have been investigated.
Water soluble poly(styrene sulfonate)-b-poly(vinylidene fluoride)-b-poly(styrene sulfonate) triblock copolymer nanoparticles
Authors: Černoch Peter , Černochová Zulfiya , Petrova Svetlana , Kaňková Dana , Kim Joon-Sung , Vasu Vignesh , Asandei Alexandru D.
Published: June 2016

Water-soluble PNaSS-b-PVDF-b-PNaSS triblock copolymer.
Robust 3D nanowebs assembled from interconnected and sandwich-like C@Fe3O4@C coaxial nanocables for enhanced Li-ion storage
Authors: Wang Yan , Qu Qunting , Han Yuyao , Gao Tian , Shao Jie , Zuo Zhichen , Liu Weijie , Shi Qiang , Zheng Honghe
Published: June 2016

Robust 3D nanowebs assembled from interlinked and sandwich-like carbon@Fe3O4@carbon coaxial nanocables are fabricated and exhibit impressive Li-storage properties.
Correction: Ultrathin porous NiO nanoflake arrays on nickel foam as an advanced electrode for high performance asymmetric supercapacitors
Authors: Wu Shuxing , Hui K. S. , Hui K. N. , Kim Kwang Ho
Published: June 2016

Correction for ‘Ultrathin porous NiO nanoflake arrays on nickel foam as an advanced electrode for high performance asymmetric supercapacitors’ by Shuxing Wu et al., J. Mater. Chem. A, 2016, DOI: 10.1039/c6ta02005d.
Substrate specificity and mapping of residues critical for transport in the high-affinity glutathione transporter Hgt1p
Authors: Zulkifli Mohammad , Yadav Shambhu , Thakur Anil , Singla Shiffalli , Sharma Monika , Bachhawat Anand Kumar
Published: June 2016

The high-affinity glutathione transporter Hgt1p of Saccharomyces cerevisiae belongs to a relatively new and structurally uncharacterized oligopeptide transporter (OPT) family. To understand the structural features required for interaction with Hgt1p, a quantitative investigation of substrate specificity of Hgt1p was carried out. Hgt1p showed a higher affinity for reduced glutathione (GSH), whereas it transported oxidized glutathione (GSSG) and other glutathione conjugates with lower affinity. To identify the residues of Hgt1p critical for substrate binding and translocation, all amino acid residues of the 13 predicted transmembrane domains (TMDs) have been subjected to mutagenesis. Functional evaluation of these 269 mutants by growth and biochemical assay followed by kinetic analysis of the severely defective mutants including previous mutagenic studies on this transporter have led to the identification of N124 (TMD1), V185 (TMD3), Q222, G225 and Y226 (TMD4), P292 (TMD5), Y374 (TMD6), L429 (TMD7) and F523 and Q526 (TMD9) as critical for substrate binding with at least 3-fold increase in Km upon mutagenesis to alanine. In addition residues Y226 and Y374 appeared to be important for differential substrate specificity. An ab initio model of Hgt1p was built and refined using these mutagenic data that yielded a helical arrangement that includes TMD3, TMD4, TMD5, TMD6, TMD7, TMD9 and TMD13 as pore-lining helices with the functionally important residues in a channel-facing orientation. Taken together the results of this study provides the first mechanistic insights into glutathione transport by a eukaryotic high-affinity glutathione transporter.
Bacterial pathogen gene regulation: a DNA-structure-centred view of a protein-dominated domain
Authors: Dorman Charles J. , Colgan Aoife , Dorman Matthew J.
Published: June 2016

The mechanisms used by bacterial pathogens to regulate the expression of their genes, especially their virulence genes, have been the subject of intense investigation for several decades. Whole genome sequencing projects, together with more targeted studies, have identified hundreds of DNA-binding proteins that contribute to the patterns of gene expression observed during infection as well as providing important insights into the nature of the gene products whose expression is being controlled by these proteins. Themes that have emerged include the importance of horizontal gene transfer to the evolution of pathogens, the need to impose regulatory discipline upon these imported genes and the important roles played by factors normally associated with the organization of genome architecture as regulatory principles in the control of virulence gene expression. Among these architectural elements is the structure of DNA itself, its variable nature at a topological rather than just at a base-sequence level and its ability to play an active (as well as a passive) part in the gene regulation process.
Immune dysfunction in patients with obstructive jaundice before and after endoscopic retrograde cholangiopancreatography
Authors: Chowdhury Abeed H. , Camara Miguel , Martinez-Pomares Luisa , Zaitoun Abed M. , Eremin Oleg , Aithal Guruprasad P. , Lobo Dileep N.
Published: June 2016

This prospective observational study investigated monocyte cytokine responses to lipopolysaccharide (LPS) in patients with obstructive jaundice (OJ) before and after endoscopic biliary drainage. Dendritic cell (DC) subsets and their expression of co-stimulatory molecules were also studied. Forty patients with OJ and ten non-jaundiced patients with normal gastroscopy findings were recruited. Ten healthy volunteers provided control blood samples for immunological assays. Patients with OJ had blood and duodenal mucosa sampled at the time of endoscopic retrograde cholangiopancreatography (ERCP) and further blood sampled during the recovery phase. Monocyte cytokine responses to LPS, DC subsets and co-stimulatory molecule expression were compared with controls. Duodenal morphology and occludin expression were also assessed. Monocytes obtained before ERCP from jaundiced patients demonstrated reduced cytokine responses to endotoxin compared with controls (IL-1β: 2678 compared with 4631 pg/ml, P=0.04 and IL-6: 3442 compared with 6157 pg/ml, P=0.002). Monocytes from patients with malignancy had poorer responses to endotoxin than from those with benign OJ (IL-1β: 2025 compared with 3332 pg/ml, P=0.001). After ERCP, the secretion of inflammatory cytokines by monocytes obtained from jaundiced patients increased (IL-1β: 2150 compared with 2520 pg/ml, P=0.03 and IL-6: 2488 compared with 3250 pg/ml, P=0.01). Occludin expression (85 compared with 95%, P=0.004) and mean duodenal villus height (334 compared with 404 μm, P=0.03) were lower in jaundiced patients. Before biliary drainage, patients with OJ had a higher percentage of myeloid dendritic cells (mDCs) and greater mDC expression of CD40 (P=0.04) and CD86 (P=0.04). Monocytes from patients with OJ had lower proinflammatory cytokine secretion in response to LPS, an effect reversed following biliary drainage.
An Application of Item Response Theory and the Rasch Model in Speech Recognition Test Materials
Authors: Ng Iris H.-Y. , Lee Kathy Y. S. , Lam Joffee H. S. , van Hasselt C. Andrew , Tong Michael C. F.
Published: June 2016

Purpose

The purpose of this study was to describe an attempt to apply item-response theory (IRT) and the Rasch model to construction of speech-recognition tests. A set of word-recognition test items applicable to children as young as 3 years old—with any level of hearing sensitivity, with or without using hearing devices—was developed.

Method

Test items were constructed through expert consultation and by reference to some established language corpora, validated with 121 participants with various degrees of hearing loss and 255 with typical hearing. IRT and the Rasch model were applied to evaluate item quality.

Results

Eighty disyllabic word items were selected in accordance with IRT. The speech-recognition abilities of the 376 young participants are reported. The IRT analyses on this set of data are also discussed.

Conclusions

A new set of speech-recognition test materials in Cantonese Chinese has been developed. Construction of short equivalent lists may be performed in accordance with IRT item qualities. Clinical applications of this test tool in the particular language population are discussed.
Metamodelling technique for the efficient design optimisation of metasurfaces
Authors: Ferranti F. , De Marcellis A. , Janneh M. , Palange E. , Antonini G.
Published: June 2016

A metamodelling technique for the efficient design optimisation of the electromagnetic response of metasurfaces is proposed. Metamodels are built starting from data samples of design performance parameters properly extracted from a few electromagnetic simulations using a system identification approach. The metamodels are then used to optimise the metasurface electromagnetic response with respect to some design specifications. Numerical results validate the efficiency and accuracy of the proposed metamodelling technique.
Model predictive control strategy for NPC grid‐connected inverters in unbalanced grids
Authors: Jin Tao , Wei Haibin , Nzongo Daniel Legrand Mon , Zhang Yizhen
Published: June 2016

A model predictive control (MPC) strategy for a three‐phase three‐level neutral point clamped (NPC) grid‐connected inverter is discussed. Conventional two‐level inverters are effective when a symmetric fault occurs. But when a three‐phase unbalanced fault occurs, they will generate errors and introduce delay in the power system because of the complex design or the neglected negative‐sequence component of the grid. To solve this problem, a new method to control a NPC grid‐connected inverter is proposed, which combines an MPC strategy with a decoupling double synchronous reference frame phase‐locked loop technique. The proposed method reduces the use of PI controllers and enhances the system's response speed. Using simulations and experiments, the proposed MPC strategy for a three‐level NPC grid‐connected inverter is proven to be accurate and reliable.
Design of dual‐band −3 dB couplers with a wide range of dual‐band frequency ratios
Authors: Chang Chih‐Chun , Chin Kuo‐Sheng , Zheng Yu‐Feng
Published: June 2016

A novel topology for designing dual‐band couplers with −3 dB coupling and a wide range of dual‐band frequency ratios is presented. The proposed structure consists of two coupled‐line sections connected by two uncoupled lines and four tapped stubs. This coupler can achieve a high frequency ratio of up to 5 by adjusting the impedance of tapped stubs. An experiment coupler operating at 0.7/2.6 GHz with a frequency ratio of 3.71 and −3 dB coupling was fabricated for demonstration.
Highly‐selective pseudoelliptic filters based on dual‐mode substrate integrated waveguide resonators
Authors: Liu Qing , Zhou Dongfang , Wang Shuxing , Zhang Yi
Published: June 2016

A non‐degenerate dual‐mode resonator derived from circular substrate integrated waveguide is proposed, and two pseudoelliptic bandpass filters with non‐resonant mode based on the dual‐mode resonators are presented. Two resonant modes (higher order modes) are employed to degenerate a passband, while a non‐resonant mode (fundamental mode) is designed to provide a direct input‐to‐output coupling. Owning to an additional path provided by non‐resonant mode, the filters have good selectivity and very compact size. The presented simulation and measurement results are in good agreement.
Path loss variation of on‐body UWB channel in the frequency bands of IEEE 802.15.6 standard
Authors: Goswami Dayananda , Sarma Kanak C. , Mahanta Anil
Published: June 2016

The wireless body area network (WBAN) has gaining tremendous attention among researchers and academicians for its envisioned applications in healthcare service. Ultra wideband (UWB) radio technology is considered as excellent air interface for communication among body area network devices. Characterisation and modelling of channel parameters are utmost prerequisite for the development of reliable communication system. The path loss of on‐body UWB channel for each frequency band defined in IEEE 802.15.6 standard is experimentally determined. The parameters of path loss model are statistically determined by analysing measurement data. Both the line‐of‐sight and non‐line‐of‐sight channel conditions are considered in the measurement. Variations of parameter values with the size of human body are analysed along with the variation of parameter values with the surrounding environments. It is observed that the parameters of the path loss model vary with the frequency band as well as with the body size and surrounding environment. The derived parameter values are specific to the particular frequency bands of IEEE 802.15.6 standard, which will be useful for the development of efficient UWB WBAN system.
Cryptography of medical images based on a combination between chaotic and neural network
Authors: Dridi Manel , Hajjaji Mohamed Ali , Bouallegue Belgacem , Mtibaa Abdellatif
Published: June 2016

This study presents a novel chaotic–neural network of image encryption and decryption image applied to the domain of medical. The main objective behind the proposed technique is to ensure the safety of medical images with a less complex algorithm compared with the existing methods. In order to improve the robustness, the totality of the pixels related to the host image is XORed with a generation key. After that, with a chaotic system (logistic map), the binary sequence is generated in order to set the weights wij and bias bi of neuron network with the goal of encrypting the pixels issued from the previous step. Simulation and experiments were carried out on medical images coded on 8 and 12 bits/pixel. The obtained results confirmed the performance and the efficiency of the proposed method, which is compliant with Digital Imaging and Communications in Medicine standards.
Cross-bifix-free sets generation via Motzkin paths
Authors: Barcucci Elena , Bilotta Stefano , Pergola Elisa , Pinzani Renzo , Succi Jonathan
Published: June 2016

Cross-bifix-free sets are sets of words such that no proper prefix of any word is a
proper suffix of any other word. In this paper, we introduce a general constructive method
for the sets of cross-bifix-free q-ary words of fixed length. It enables us to
determine a cross-bifix-free words subset which has the property to be non-expandable.
Bosonic lasers: The state of the art (Review Article)
Authors: Kavokin Alexey , Liew Timothy C. H. , Schneider Christian , Höfling Sven
Published: June 2016

Bosonic lasers represent a new generation of coherent light sources. In contrast to conventional, fermionic, lasers they do not require inversion of electronic population and do not rely on the stimulated emission of radiation. Bosonic lasers are based on the spontaneous emission of light by condensates of bosonic quasiparticles. The first realization of bosonic lasers has been reported in semiconductor microcavities where bosonic condensates of exciton-polaritons first studied several decades ago by K. B. Tolpygo can be formed under optical or electronic pumping. In this paper we overview the recent progress in the research area of polaritonics, address the perspective of realization of polariton devices: from bosonic cascade lasers to spin transistors and switches.
Polaritons in a nonideal array of ultracold quantum dots
Authors: Rumyantsev V. V. , Fedorov S. A. , Gumennyk K. V.
Published: June 2016

We develop a numerical model for a defect-containing square lattice of microcavities with embedded ultracold atomic clusters (quantum dots). It is assumed that certain fractions of quantum dots and cavities are absent, which leads to transformation of polariton spectrum of the overall structure. The dispersion relations for polaritonic modes are derived as functions of defect concentrations and on this basis the band gap, the effective masses of lower and upper dispersion branch polaritons as well as their densities of states are evaluated.
Rayleigh and Wood anomalies in the diffraction of acoustic waves from the periodically corrugated surface of an elastic medium
Authors: Maradudin A. A. , Simonsen I.
Published: June 2016

By the use of the Rayleigh method we have calculated the angular dependence of the reflectivity and the efficiencies of several other diffracted orders when the periodically corrugated surface of an isotropic elastic medium is illuminated by a volume acoustic wave of shear horizontal polarization. These dependencies display the signatures of Rayleigh and Wood anomalies, usually associated with the diffraction of light from a metallic grating. The Rayleigh anomalies occur at angles of incidence at which a diffracted order appears or disappears; the Wood anomalies here are caused by the excitation of the shear horizontal surface acoustic waves supported by the periodically corrugated surface of an isotropic elastic medium. The dispersion curves of these waves in both the nonradiative and radiative regions of the frequency-wavenumber plane are calculated, and used in predicting the angles of incidence at which the Wood anomalies are expected to occur.
Tunneling through localized barrier states in superconducting heterostructures
Authors: Shaternik V. E. , Shapovalov A. P. , Suvorov A. V. , Skoryk N. A. , Belogolovskii M. A.
Published: June 2016

Thin film heterostructures composed of superconducting electrodes (molybdenum rhenium alloy) and a nanoscale silicon layer doped with tungsten, have been designed and experimentally studied. The current-voltage characteristics of junctions exhibiting local maxima of the current against the background of abrupt current increases for the first time, were measured in the voltage range of −800 to 800 mV, at temperatures of 4.2–8 K. The positions of these singularities, which are symmetrical with respect to zero voltage, varied from sample to sample within the range of 40–300 mV. With increasing temperature, they became blurred and completely vanished with the disappearance of superconductivity in the electrodes. The nature of the observed singularities is associated with the properties of electron tunneling through the impurity states localized in the semiconducting barrier. The use of a superconducting electrode enhances the interaction of the localized electron with the conduction electrons thanks to the root divergence in the density of electron states of a superconductor.
Role of acoustic phonons in the negative thermal expansion of layered structures and nanotubes based on them
Authors: Eremenko V. V. , Sirenko A. F. , Sirenko V. A. , Dolbin A. V. , Gospodarev I. A. , Syrkin E. S. , Feodosyev S. B. , Bondar I. S. , Minakova K. A.
Published: June 2016

Calculations on a microscopic level are used to explain the experimentally observed negative linear thermal expansion along some directions in a number of crystalline compounds with complicated lattices and anisotropic interactions between atoms. Anomalies in the temperature dependence of the coefficient of linear thermal expansion are analyzed in layered crystals made up of monatomic layers (graphite and graphene nanofilms) and multilayer “sandwiches” (transition metal dichalcogenides), in multilayered crystal structures such as high-temperature superconductors where the anisotropy of the interatomic interactions is not conserved in the long-range order, and in graphene nanotubes. The theoretical calculations are compared with data from x-ray, neutron diffraction, and dilatometric measurements.
Canonical quantization of lattice Higgs-Yang-Mills fields: Krein essential selfadjointness of the Hamiltonian
Authors: Challifour John L. , Timko Edward J.
Published: June 2016

Using a Krein indefinite metric in Fock space, the Hamiltonian for cut-off models of canonically quantized Higgs-Yang-Mills fields interpolating between the Gupta-Bleuler-Feynman and Landau gauges is shown to be essentially maximal accretive and essentially Krein selfadjoint.