bluuebunny/crossref_metadata_2025_split huggingface dataset:
Realizing high figure of merit in heavy-band p-type half-Heusler thermoelectric materials
Authors: Fu Chenguang , Bai Shengqiang , Liu Yintu , Tang Yunshan , Chen Lidong , Zhao Xinbing , Zhu Tiejun 
Published: September 2015

AbstractSolid-state thermoelectric technology offers a promising solution for converting waste heat to useful electrical power. Both high operating temperature and high figure of merit zT are desirable for high-efficiency thermoelectric power generation. Here we report a high zT of ∼1.5 at 1,200 K for the p-type FeNbSb heavy-band half-Heusler alloys. High content of heavier Hf dopant simultaneously optimizes the electrical power factor and suppresses thermal conductivity. Both the enhanced point-defect and electron–phonon scatterings contribute to a significant reduction in the lattice thermal conductivity. An eight couple prototype thermoelectric module exhibits a high conversion efficiency of 6.2% and a high power density of 2.2 W cm−2 at a temperature difference of 655 K. These findings highlight the optimization strategy for heavy-band thermoelectric materials and demonstrate a realistic prospect of high-temperature thermoelectric modules based on half-Heusler alloys with low cost, excellent mechanical robustness and stability.
The links between ecosystem multifunctionality and above- and belowground biodiversity are mediated by climate
Authors: Jing Xin , Sanders Nathan J. , Shi Yu , Chu Haiyan , Classen Aimée T. , Zhao Ke , Chen Litong , Shi Yue , Jiang Youxu , He Jin-Sheng 
Published: September 2015

AbstractPlant biodiversity is often correlated with ecosystem functioning in terrestrial ecosystems. However, we know little about the relative and combined effects of above- and belowground biodiversity on multiple ecosystem functions (for example, ecosystem multifunctionality, EMF) or how climate might mediate those relationships. Here we tease apart the effects of biotic and abiotic factors, both above- and belowground, on EMF on the Tibetan Plateau, China. We found that a suite of biotic and abiotic variables account for up to 86% of the variation in EMF, with the combined effects of above- and belowground biodiversity accounting for 45% of the variation in EMF. Our results have two important implications: first, including belowground biodiversity in models can improve the ability to explain and predict EMF. Second, regional-scale variation in climate, and perhaps climate change, can determine, or at least modify, the effects of biodiversity on EMF in natural ecosystems.
SC06, a novel small molecule compound, displays preclinical activity against multiple myeloma by disrupting the mTOR signaling pathway
Authors: Han Kunkun , Xu Xin , Xu Zhuan , Chen Guodong , Zeng Yuanying , Zhang Zubin , Cao Biyin , Kong Yan , Tang Xiaowen , Mao Xinliang 
Published: September 2015

AbstractThe mammalian target of rapamycin (mTOR) is extensively involved in multiple myeloma (MM) pathophysiology. In the present study, we reported a novel small molecule SC06 that induced MM cell apoptosis and delayed MM xenograft growth in vivo. Oral administration of SC06 to mice bearing human MM xenografts resulted in significant inhibition of tumor growth at doses that were well tolerated. Mechanistic studies revealed that SC06 selectively inhibited the mTOR signaling pathway but had no effects on other associated kinases, such as AKT, ERK, p38, c-Src and JNK. Further studies showed that SC06-decreased mTOR activation was associated with the downregulation of Raptor, a key component of the mTORC1 complex. SC06 also suppressed the phosphorylation of 4E-BP1 and P70S6K, two typical substrates in the mTORC1 signaling pathway. Notably, expression of Raptor, phosphorylation of mTOR and phosphorylated 4E-BP1 was also decreased in the tumor tissues from SC06-treated mice, which was consistent with the cellular studies. Therefore, given the potency and low toxicity, SC06 could be developed as a potential anti-MM drug candidate by disrupting the mTOR signaling.
Wide-Angle Viewing System versus Conventional Indirect Ophthalmoscopy for Scleral Buckling
Authors: Tomita Yohei , Kurihara Toshihide , Uchida Atsuro , Nagai Norihiro , Shinoda Hajime , Tsubota Kazuo , Ozawa Yoko 
Published: September 2015

AbstractWide-angle viewing systems (WAVSs) were originally established for pars plana vitrectomy. However, their application to scleral buckling surgery was recently reported. In this study, we compared the outcomes of scleral buckling using a noncontact WAVS with that of scleral buckling using conventional indirect ophthalmoscopy for rhegmatogenous retinal detachment. The clinical records of 39 eyes (39 patients) with rhegmatogenous retinal detachment primarily treated between November 2012 and June 2014 at the Vitreo-Retina Surgical Division Clinic at the Department of Ophthalmology, Keio University Hospital were retrospectively reviewed. Scleral bucking was performed using WAVS with surgical placement of an endoilluminator in 16 eyes and indirect ophthalmoscopy in 23 eyes. The patients in these groups were consecutive over different intervals. The preoperative demographics, success rate of retinal reattachment, intraoperative findings and postoperative complications were evaluated. There were no significant differences in pre- or postoperative conditions between groups and similar surgical outcomes were achieved with the WAVS and conventional procedures. However, compared with the conventional procedure, the WAVS procedure resulted in fewer intraoperative corneal epithelial disorders (p = 0.049) and decreased the surgical duration of segmental buckling (p = 0.02); therefore, it may be suggested as an effective alternative procedure.
The generalized Shockley-Queisser limit for nanostructured solar cells
Authors: Xu Yunlu , Gong Tao , Munday Jeremy N. 
Published: September 2015

AbstractThe Shockley-Queisser limit describes the maximum solar energy conversion efficiency achievable for a particular material and is the standard by which new photovoltaic technologies are compared. This limit is based on the principle of detailed balance, which equates the photon flux into a device to the particle flux (photons or electrons) out of that device. Nanostructured solar cells represent a novel class of photovoltaic devices and questions have been raised about whether or not they can exceed the Shockley-Queisser limit. Here we show that single-junction nanostructured solar cells have a theoretical maximum efficiency of ∼42% under AM 1.5 solar illumination. While this exceeds the efficiency of a non-concentrating planar device, it does not exceed the Shockley-Queisser limit for a planar device with optical concentration. We consider the effect of diffuse illumination and find that with optical concentration from the nanostructures of only × 1,000, an efficiency of 35.5% is achievable even with 25% diffuse illumination. We conclude that nanostructured solar cells offer an important route towards higher efficiency photovoltaic devices through a built-in optical concentration.
Reconfigurable multi-scale colloidal assembly on excluded volume patterns
Authors: Edwards Tara D. , Yang Yuguang , Everett W. Neil , Bevan Michael A. 
Published: September 2015

AbstractThe ability to create multi-scale, periodic colloidal assemblies with unique properties is important to emerging applications. Dynamically manipulating colloidal structures via tunable kT-scale attraction can provide the opportunity to create particle-based nano- and microstructured materials that are reconfigurable. Here, we report a novel tactic to obtain reconfigurable, multi-scale, periodic colloidal assemblies by combining thermoresponsive depletant particles and patterned topographical features that, together, reversibly mediate local kT-scale depletion interactions. This method is demonstrated in optical microscopy experiments to produce colloidal microstructures that reconfigure between well-defined ordered structures and disordered fluid states as a function of temperature and pattern feature depth. These results are well described by Monte Carlo simulations using theoretical depletion potentials that include patterned excluded volume. Ultimately, the approach reported here can be extended to control the size, shape, orientation and microstructure of colloidal assemblies on multiple lengths scales and on arbitrary pre-defined pattern templates.
Mimicking a natural pathway for de novo biosynthesis: natural vanillin production from accessible carbon sources
Authors: Ni Jun , Tao Fei , Du Huaiqing , Xu Ping 
Published: September 2015

AbstractPlant secondary metabolites have been attracting people’s attention for centuries, due to their potentials; however, their production is still difficult and costly. The rich diversity of microbes and microbial genome sequence data provide unprecedented gene resources that enable to develop efficient artificial pathways in microorganisms. Here, by mimicking a natural pathway of plants using microbial genes, a new metabolic route was developed in E. coli for the synthesis of vanillin, the most widely used flavoring agent. A series of factors were systematically investigated for raising production, including efficiency and suitability of genes, gene dosage and culture media. The metabolically engineered strain produced 97.2 mg/L vanillin from l-tyrosine, 19.3 mg/L from glucose, 13.3 mg/L from xylose and 24.7 mg/L from glycerol. These results show that the metabolic route enables production of natural vanillin from low-cost substrates, suggesting that it is a good strategy to mimick natural pathways for artificial pathway design.
Tet-mediated imprinting erasure in H19 locus following reprogramming of spermatogonial stem cells to induced pluripotent stem cells
Authors: Bermejo-Álvarez P. , Ramos-Ibeas P. , Park K.E. , Powell A. P. , Vansandt L. , Derek Bickhart , Ramirez M. A. , Gutiérrez-Adán A. , Telugu B. P. 
Published: September 2015

AbstractSelective methylation of CpG islands at imprinting control regions (ICR) determines the monoparental expression of a subset of genes. Currently, it is unclear whether artificial reprogramming induced by the expression of Yamanaka factors disrupts these marks and whether cell type of origin affects the dynamics of reprogramming. In this study, spermatogonial stem cells (SSC) that harbor paternalized imprinting marks and fibroblasts were reprogrammed to iPSC (SSCiPSC and fiPSC). The SSCiPSC were able to form teratomas and generated chimeras with a higher skin chimerism than those derived from fiPSC. RNA-seq revealed extensive reprogramming at the transcriptional level with 8124 genes differentially expressed between SSC and SSCiPSC and only 490 between SSCiPSC and fiPSC. Likewise, reprogramming of SSC affected 26 of 41 imprinting gene clusters known in the mouse genome. A closer look at H19 ICR revealed complete erasure in SSCiPSC in contrast to fiPSC. Imprinting erasure in SSCiPSC was maintained even after in vivo differentiation into teratomas. Reprogramming of SSC from Tet1 and Tet2 double knockout mice however lacked demethylation of H19 ICR. These results suggest that imprinting erasure during reprogramming depends on the epigenetic landscape of the precursor cell and is mediated by TETs at the H19 locus.
Europium Luminescence: Electronic Densities and Superdelocalizabilities for a Unique Adjustment of Theoretical Intensity Parameters
Authors: Dutra José Diogo L. , Lima Nathalia B. D. , Freire Ricardo O. , Simas Alfredo M. 
Published: September 2015

AbstractWe advance the concept that the charge factors of the simple overlap model and the polarizabilities of Judd-Ofelt theory for the luminescence of europium complexes can be effectively and uniquely modeled by perturbation theory on the semiempirical electronic wave function of the complex. With only three adjustable constants, we introduce expressions that relate: (i) the charge factors to electronic densities and (ii) the polarizabilities to superdelocalizabilities that we derived specifically for this purpose. The three constants are then adjusted iteratively until the calculated intensity parameters, corresponding to the 5D0→7F2 and 5D0→7F4 transitions, converge to the experimentally determined ones. This adjustment yields a single unique set of only three constants per complex and semiempirical model used. From these constants, we then define a binary outcome acceptance attribute for the adjustment and show that when the adjustment is acceptable, the predicted geometry is, in average, closer to the experimental one. An important consequence is that the terms of the intensity parameters related to dynamic coupling and electric dipole mechanisms will be unique. Hence, the important energy transfer rates will also be unique, leading to a single predicted intensity parameter for the 5D0→7F6 transition.
Does the climate warming hiatus exist over the Tibetan Plateau?
Authors: Duan Anmin , Xiao Zhixiang 
Published: September 2015

AbstractThe surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998–2013 (0.25 °C decade−1), compared with that during 1980–1997 (0.21 °C decade−1). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud–radiation feedback. The increased nocturnal cloud over the northern Tibetan Plateau would warm the nighttime temperature via enhanced atmospheric back-radiation, while the decreased daytime cloud over the southern Tibetan Plateau would induce the daytime sunshine duration to increase, resulting in surface air temperature warming. Meanwhile, the in situ surface wind speed has recovered gradually since 1998 and thus the energy concentration cannot explain the accelerated warming trend over the Tibetan Plateau after the 1990s. It is suggested that cloud–radiation feedback may play an important role in modulating the recent accelerated warming trend over the Tibetan Plateau.
Fibroblast growth factor 21 in breast milk controls neonatal intestine function
Authors: Gavaldà-Navarro Aleix , Hondares Elayne , Giralt Marta , Mampel Teresa , Iglesias Roser , Villarroya Francesc 
Published: September 2015

AbstractFGF21 is a hormonal factor with important functions in the control of metabolism. FGF21 is found in rodent and human milk. Radiolabeled FGF21 administered to lactating dams accumulates in milk and is transferred to neonatal gut. The small intestine of neonatal (but not adult) mice highly expresses β-Klotho in the luminal area. FGF21-KO pups fed by FGF21-KO dams showed decreased expression and circulating levels of incretins (GIP and GLP-1), reduced gene expression of intestinal lactase and maltase-glucoamylase and low levels of galactose in plasma, all associated with a mild decrease in body weight. When FGF21-KO pups were nursed by wild-type dams (expressing FGF21 in milk), intestinal peptides and digestive enzymes were up-regulated, lactase enzymatic activity was induced and galactose levels and body weight were normalized. Neonatal intestine explants were sensitive to FGF21, as evidenced by enhanced ERK1/2 phosphorylation. Oral infusion of FGF21 into neonatal pups induced expression of intestinal hormone factors and digestive enzymes, lactase activity and lactose absorption. These findings reveal a novel role of FGF21 as a hormonal factor contributing to neonatal intestinal function via its presence in maternal milk. Appropriate signaling of FGF21 to neonate is necessary to ensure optimal digestive and endocrine function in developing intestine.
Effect of miR-34a in regulating steatosis by targeting PPARα expression in nonalcoholic fatty liver disease
Authors: Ding Jiexia , Li Meng , Wan Xingyong , Jin Xi , Chen Shaohua , Yu Chaohui , Li Youming 
Published: September 2015

AbstractMicroRNA-34a (miR-34a) is thought to be involved in nonalcoholic fatty liver disease (NAFLD). However, the association between altered expression of miR-34a and the pathophysiological features of NAFLD remains unclear. Here, we investigated the mechanisms by which miR-34a influences NAFLD through the PPARα-related pathway. Real-time quantitative PCR, western blotting and other assays kit were used to investigate the expression and function of miR-34a in an NAFLD model. Cultured cells transfected with miR-34a inhibitor and C57BL/6 mice injected with the miR-34a inhibitor through vein tail were conducted for the effects of miR-34a on its target. MiR-34a levels were significantly upregulated in steatosis-induced hepatocytes and in liver tissues of high-fat diet-fed mice. The upregulation of miR-34a resulted in the downregulation of hepatic PPARα and SIRT1 that are the direct targets of miR-34a. Silencing miR-34a led to an initially increased expression of PPARα, SIRT1 and PPARα’s downstream genes. Activation of the central metabolic sensor AMPK was also increased. The miR-34a inhibitor suppressed lipid accumulation and improved the degree of steatosis. Taken together, our data indicated that decreased expression of miR-34a potentially contributes to altered lipid metabolism in NAFLD. Downregulation of miR-34a may be a therapeutic strategy against NAFLD by regulating its target PPARα and SIRT1.
Micro-concentration Lipopolysaccharide as a Novel Stimulator of Megakaryocytopoiesis that Synergizes with IL-6 for Platelet Production
Authors: Wu Di , Xie Jun , Wang Xuejun , Zou Bingcheng , Yu Yin , Jing Tao , Zhang Songmei , Zhang Qing 
Published: September 2015

AbstractLipopolysaccharide (LPS) induces platelet activation and enhances platelet sensitivity to aggregation, which might alter platelet counts. We found that serial doses of micro-concentration LPS significantly increased the platelet count in mice treated with kanamycin, along with increased expression of IL-6 compared with IL-3 and TPO in megakaryocytes obtained from the mouse bone morrow following LPS administration. Furthermore, LPS at lower levels ranging plus IL-6 effectively stimulated CFU-MK formation and increased CD41 expression and megakaryocyte polyploidization. Meanwhile, there was a sustained rise in the percentage of reticulated platelets in the whole blood in response to low-dosage LPS combined with IL-6. In vivo experiments also demonstrated that the administration of LPS combined with IL-6 substantially enhanced the number of circulating platelets in normal and thrombocytopenic mice. Notably, the optimal LPS concentration in combination with IL-6 might be a novel stimulator of TLR4 and IL-6R expression in Dami cell lines, which initially occurs through TLR4-IL-6R crosstalk and then involves the activation of NF-κB and phosphorylation of p38 MAPK. These data suggest a new paradigm for the regulation of megakaryocytopoiesis and platelet production via a synergistic effect of LPS and IL-6, which has the potential to be used for the design of new therapies.
Cellular and molecular effects of the mTOR inhibitor everolimus
Authors: Saran Uttara , Foti Michelangelo , Dufour Jean-François 
Published: September 2015

mTOR (mechanistic target of rapamycin) functions as the central regulator for cell proliferation, growth and survival. Up-regulation of proteins regulating mTOR, as well as its downstream targets, has been reported in various cancers. This has promoted the development of anti-cancer therapies targeting mTOR, namely fungal macrolide rapamycin, a naturally occurring mTOR inhibitor, and its analogues (rapalogues). One such rapalogue, everolimus, has been approved in the clinical treatment of renal and breast cancers. Although results have demonstrated that these mTOR inhibitors are effective in attenuating cell growth of cancer cells under in vitro and in vivo conditions, subsequent sporadic response to rapalogues therapy in clinical trials has promoted researchers to look further into the complex understanding of the dynamics of mTOR regulation in the tumour environment. Limitations of these rapalogues include the sensitivity of tumour subsets to mTOR inhibition. Additionally, it is well known that rapamycin and its rapalogues mediate their effects by inhibiting mTORC (mTOR complex) 1, with limited or no effect on mTORC2 activity. The present review summarizes the pre-clinical, clinical and recent discoveries, with emphasis on the cellular and molecular effects of everolimus in cancer therapy.
Tunable microstrip lowpass filter with compact size and ultra‐wide stopband
Authors: Cai Chuantao , Wang Jianpeng , Zhang Gang 
Published: September 2015

A compact varactor‐tuned microstrip lowpass filter (LPF) with a large cutoff frequency tuning range and an ultra‐wide stopband is presented. By employing a pair of parallel coupled‐lines and a low‐impedance stub loaded with a varactor diode, the introduced filter can successfully realise the tunable cutoff frequency function. Besides, both radial patch resonators and stepped‐impedance resonators are introduced to achieve an ultra‐wide stopband in all the states in this design. A varactor‐tuned microstrip LPF is designed, fabricated and measured. The measured results show that the proposed LPF provides not only a large cutoff frequency tuning range of 91.3% from 0.85 to 2.28 GHz, but also an ultra‐wide stopband which extends to 20 GHz.
4.3 μW 10 fA‐sensitivity dual‐mode current converter for implantable glucose monitoring
Authors: Tan Xi , Chen Xianliang , Zhang Yiwu , Wang Junyu , Min Hao , Huang Yue , Mason Andrew J. 
Published: September 2015

A low‐power, high‐sensitive current converter for implantable electrochemical glucose sensor tags based on radio frequency identification is presented. The current converter can work in the incremental sigma delta (ΣΔ) converter mode or the dual‐slope converter mode. The two modes can be switched automatically according to the input current value for the target measuring range from 10 fA to 1 nA. The dual‐mode converter offers a 10 fA‐input current sensitivity, 100 dB dynamic range and consumes 4.26 μW of power from a 1.5 V supply.