Narrowing the gap between theoretical and actual capacity in key Li-based battery systems can be achieved through improvements in both electronic and ionic conductivities of materials, via addition ...of conductive species. Additives do, however, penalize both volumetric and gravimetric properties, and also limit liquid transport and high rate performance. In this work, we developed a technique to design and optimize cathode system based directly on the relationships among ionic and electronic conductivities and specific energy, for a range of commercially viable cathode electrochemistries and additives. Our results quantify trade-offs among ionic and electronic conductivity, and conductivity and specific energy. We also provide quantitative relationships for improved utilization and specific power, with higher specific energy. Finally, we provide quantitative guidance for the design of high energy density Li(Ni
1/3Co
1/3Mn
1/3)O
2 cells using conductive additives, and also provide guidelines for the design of cathode systems, based directly on solid and liquid phase transport limitations. Future work will focus on higher rates of performance, and will be based on analyses here.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The optical design and performance of the recently opened 13A biological small‐angle X‐ray scattering (SAXS) beamline at the 3.0 GeV Taiwan Photon Source of the National Synchrotron Radiation ...Research Center are reported. The beamline is designed for studies of biological structures and kinetics in a wide range of length and time scales, from angstrom to micrometre and from microsecond to minutes. A 4 m IU24 undulator of the beamline provides high‐flux X‐rays in the energy range 4.0–23.0 keV. MoB4C double‐multilayer and Si(111) double‐crystal monochromators (DMM/DCM) are combined on the same rotating platform for a smooth rotation transition from a high‐flux beam of ∼4 × 1014 photons s−1 to a high‐energy‐resolution beam of ΔE/E ≃ 1.5 × 10−4; both modes share a constant beam exit. With a set of Kirkpatrick–Baez (KB) mirrors, the X‐ray beam is focused to the farthest SAXS detector position, 52 m from the source. A downstream four‐bounce crystal collimator, comprising two sets of Si(311) double crystals arranged in a dispersive configuration, optionally collimate the DCM (vertically diffracted) beam in the horizontal direction for ultra‐SAXS with a minimum scattering vector q down to 0.0004 Å−1, which allows resolving ordered d‐spacing up to 1 µm. A microbeam, of 10–50 µm beam size, is tailored by a combined set of high‐heat‐load slits followed by micrometre‐precision slits situated at the front‐end 15.5 m position. The second set of KB mirrors then focus the beam to the 40 m sample position, with a demagnification ratio of ∼1.5. A detecting system comprising two in‐vacuum X‐ray pixel detectors is installed to perform synchronized small‐ and wide‐angle X‐ray scattering data collections. The observed beamline performance proves the feasibility of having compound features of high flux, microbeam and ultra‐SAXS in one beamline.
The optical design and performance of the BioSAXS beamline at the Taiwan Photon Source are reported
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Aliment Pharmacol Ther 2011; 34: 994–1004
Summary
Background The diagnosis of gastro‐oesophageal reflux disease (GERD) is based on reflux symptoms. Although metabolic syndrome has been linked to ...erosive oesophagitis (EO), the impact of insulin resistance, the core of the metabolic syndrome, on reflux symptoms remains to be elucidated.
Aim To assess the effects of insulin resistance on GERD, including both endoscopic findings and symptoms.
Methods A total of 743 sonographic noncirrhotic adult subjects, who underwent an upper gastrointestinal endoscopic examination, completed a gastro‐oesophageal reflux questionnaire and had available fasting insulin data were included. Endoscopic findings were classified according to the Los Angeles classification. Homeostatic model assessment‐insulin resistance (HOMA‐IR) index was used to evaluate the status of insulin resistance. Univariate and multivariate approaches were used to evaluate the associations between insulin resistance and GERD.
Results Older age, male gender, smoking and alcohol consumption increased the prevalence of EO, but not GERD symptoms. A large waist circumference, high fasting blood glucose levels and high number of metabolic syndrome components were associated with increased prevalence of both EO and GERD symptoms, while high blood pressure was associated with increased prevalence of EO only. Moreover, higher scores in the gastro‐oesophageal reflux questionnaire were associated with higher HOMA‐IR index, and higher HOMA‐IR index was associated with increased prevalence of EO (adjusted odds ratio 1.14, 95% CI 1.03–1.26, P = 0.012).
Conclusions Our findings demonstrate clear associations between insulin resistance, metabolic syndrome and GERD. Whether reducing insulin resistance may improve GERD symptoms or EO deserves prospective study.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
With the aim of gathering temporal trends on bacterial epidemiology and resistance from multiple laboratories in China, the CHINET surveillance system was organized in 2005. Antimicrobial ...susceptibility testing was carried out according to a unified protocol using the Kirby-Bauer method or automated systems. Results were analyzed according to Clinical and Laboratory Standards Institute (CLSI) 2014 definitions. Between 2005 and 2014, the number of bacterial isolates ranged between 22 774 and 84 572 annually. Rates of extended-spectrum β-lactamase production among Escherichia coli isolates were stable, between 51.7 and 55.8%. Resistance of E. coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, piperacillin/tazobactam and cefoperazone/sulbactam decreased with time. Carbapenem resistance among K. pneumoniae isolates increased from 2.4 to 13.4%. Resistance of Pseudomonas aeruginosa strains against all of antimicrobial agents tested including imipenem and meropenem decreased with time. On the contrary, resistance of Acinetobacter baumannii strains to carbapenems increased from 31 to 66.7%. A marked decrease of methicillin resistance from 69% in 2005 to 44.6% in 2014 was observed for Staphylococcus aureus. Carbapenem resistance rates in K. pneumoniae and A. baumannii in China are high. Our results indicate the importance of bacterial surveillance studies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Flexible and stretchable physical sensors capable of both energy harvesting and self‐powered sensing are vital to the rapid advancements in wearable electronics. Even so, there exist few studies that ...can integrate energy harvesting and self‐powered sensing into a single electronic skin. Here, a stretchable and washable skin‐inspired triboelectric nanogenerator (SI‐TENG) is developed for both biomechanical energy harvesting and versatile pressure sensing. A planar and designable conductive yarn network constructed from a three‐ply‐twisted silver‐coated nylon yarn is embedded into flexible elastomer, endowing the SI‐TENG with desired stretchability, good sensitivity, high detection precision, fast responsivity, and excellent mechanical stability. With a maximum average power density of 230 mW m−2, the SI‐TENG is able to light up 170 light‐emitting diodes, charge various capacitors, and drive miniature electronic products. As a self‐powered multifunctional sensor, the SI‐TENG is adopted to monitor human physiological signals, such as arterial pulse and voice vibrations. Furthermore, an intelligent prosthetic hand, a self‐powered pedometer/speedometer, a flexible digital keyboard, and a proof‐of‐concept pressure‐sensor array with 8 × 8 sensing pixels are successively demonstrated to further confirm its versatile application prospects. Based on these merits, the developed SI‐TENG has promising applications in wearable powering technology, physiological monitoring, intelligent prostheses, and human–machine interfaces.
A flexible, stretchable, washable, and multifunctional triboelectric‐based electronic skin obtained by embedding a planar and designable yarn electrode network into transparent elastomer is presented for both biomechanical energy harvesting and self‐powered pressure sensing. An energy harvester, physiological monitor, prosthetic hand, real‐time pedometer/speedometer, flexible digital keyboard, and tactile sensing array are successively demonstrated in order to confirm its versatile application prospects.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
DNA topoisomerases are the magicians of the DNA world by allowing DNA strands or double helices to pass through each other, they can solve all of the topological problems of DNA in replication, ...transcription and other cellular transactions. Extensive biochemical and structural studies over the past three decades have provided molecular models of how the various subfamilies of DNA topoisomerase manipulate DNA. In this review, the cellular roles of these enzymes are examined from a molecular point of view.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
It is difficult for liquid water to erupt onto the surface of icy satellites, such as Europa and Enceladus, because liquid water is more dense than ice. If the ice shell thickens, the volume ...expansion of ice upon freezing increases pressure in the subsurface ocean. The excess pressure is determined by a balance between compression of ocean water and elastic expansion of the ice shell. We show that on Europa the freezing of ∼ 1–10 km of ice generates tangential stresses that exceed the tensile strength of ice. Excess pressure, however, is insufficient for liquid water to erupt to the surface. Within smaller icy satellites, such as Enceladus, ocean pressure can become large enough to cause an eruption of large amounts of liquid water.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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