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Exploiting low-cost and bifunctional electrodes for the hydrogen evolution reaction (HER) and hydrazine hydrate oxidation (HzOR) is significant for the efficient generation of H 2 , but still some challenges remain. In this work, the in-situ growth of the Co-modified bimetallic hydroxysulfide (NiFeSOH) nanosheet arrays is realized by a simple aging method. The NiFe foam (NFF) is used as self-sacrificing Ni and Fe sources and happens coupling reaction with the surface-modified Co2+, resulting in the self-reconstruction of hydroxysulfide on NFF. Remarkably, the catalytic active sites and reaction kinetics are optimized by the introduction of Co centers, which endows the catalyst with greatly improved catalytic activity for both HER and HzOR. As a consequence, the Co–FeNiSOH/NFF sample shows low potentials toward HER (−0.266 V) and HzOR (0.355 V) at 100 mA cm−2 in an alkaline medium. In addition, the Co–FeNiSOH/NFF-based electrolyzer realizes small cell voltages of 0.26 V and 0.64 V at the current density of 10 mA cm−2 and 100 mA cm−2, respectively, that outperforms most reported hydroxide materials. Our work develops efficient bifunctional HER/HzOR electrodes, which may provide a promising way for the preparation of the other catalysts in H 2 generation. A novel type of Co-modified bimetallic hydroxysulfide (NiFeSOH) nanosheet arrays are developed by a rapid two-step oxidation approach. Benefiting from multiple synergistic advantages, the Co–FeNiSOH/NFF shows the excellent bifunctional activity and high stability for HzOR-assisted water splitting. [Display omitted] • The Co–FeNiSOH nanosheet arrays are first synthesized on NiFe foam. • NiFe foam used as supporter and Ni/Fe sources for the reconstruction of catalyst. • Superior bifunctional catalytic activity of HER/HzOR are demonstrated. • The multiple synergistic advantages improve the catalytic performance. • The constructed electrolyzer realizes small cell voltage of 0.26 V at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Large-scale generation of high-purity hydrogen (H 2) from simple hydrolysis strategy is vital, but the traditional technologies remain problems of economy and efficiency. Herein, a new and low-cost technical route is highlighted to realize the litre-level and efficient production of high-purity H 2 from sodium hypophosphite (NaH 2 PO 2) hydrolysis at room temperature. The formation and stabilization of CuH species on the designed Cu–Cu 2 O/CuH catalyst plays a key role in stimulating a continuous reversible NaH 2 PO 2 hydrolysis cycle for H 2. Impressively, this new technology achieves the high generated rate of 3.3 L h−1•cm−2 for H 2 in alkaline media, which outperforms the other existing hydrolysis technologies. The proposed catalytic mechanism involves renewable CuH active species catalyzing the spontaneous reaction of NaH 2 PO 2 and H 2 O to form H 2 gas and phosphate. From the view of practical application, the developed coupling catalytic system also operates efficiently in deionized water, seawater and tap water solutions, shows unique interference immunity and high stability of convenient H 2 generation. A new strategy of H 2 production is developed by using Cu–Cu 2 O/CuH and NaH 2 PO 2 as synergistic catalytic system, which shows high generated rates and superior stability of high purity H 2 fuel at room temperature. The developed H 2 generation pathway has huge potential advantages over the traditional H 2 storage materials and water electrolysis. [Display omitted] • New and low-cost technical route of NaH 2 PO 2 hydrolysis for H 2 generation. • Litre-level and efficient production of high-purity H 2 (3.3 L•h-1•cm−2) at room temperature. • Renewable CuH active species catalyzing the NaH 2 PO 2 and H 2 O to H 2 gas and phosphate. • The developed technology shows high stability and applicability under different conditions. [ABSTRACT FROM AUTHOR]

The electrocatalytic CO 2 reduction reaction (CO 2 RR) is an effective and sustainable route to achieve carbon neutrality by generating valuable fuels and feedstocks from renewable electricity. CO as one of the most economically valuable products, has been used for a wide range of applications in the synthesis of commodity and specialty chemicals. Single atom catalysts (SACs) are emerging as highly-active electrocatalysts for CO product from CO 2 RR due to high atomic utilization, adjustable coordination environment and strong metal-support interactions. Thus, the significant progresses force a comprehensive and critical summary reporting the microenvironment regulation strategies of SACs for CO 2 to CO, however, has been rarely reported. In this review, we focus on the current developed various design of microenvironment regulation strategies, including the design of metal catalytic center, the regulation of coordination environment (unsaturated coordination, oversaturated coordination, and heteroatom doping), support effect, and defect effect, to conduct the summary. It is generally believed that the change of microenvironment has an important effect on the electron distribution of the active site and the adsorption energy of the reaction intermediates. Here, we attempt to reveal the essential source of single-atom catalytic activity through in-depth understanding of microenvironment regulation. And we hope to provide help for large-scale application of advanced SACs. [Display omitted] • The microenvironment regulation strategies of SACs for CO 2 to CO was summarized. • The underlying structure-activity relationship between SACs catalysts and CO 2 RR performance was elaborated. • The catalytic mechanism caused by optimizing the geometrical and electronic structure of the active site are discussed. • The rational design of SACs catalysts with unique physicochemical properties are fully discussed. [ABSTRACT FROM AUTHOR]

Given increased international travel, immigration, and climate change, bacterial and viral infections that were once unrecognized or uncommon are being seen more frequently in the Western Hemisphere. A delay in diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. We review the epidemiology, cutaneous manifestations, diagnosis, and management of these emerging bacterial and viral diseases. [ABSTRACT FROM AUTHOR]

Given increased international travel, immigration, changing climate conditions, and the increased incidence of iatrogenic immunosuppression, fungal, protozoan, helminthic, and ectoparasitic infections that were once uncommon are being seeing more frequently in the Western hemisphere. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. In addition, delays in the diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. We review the epidemiology, cutaneous manifestations, diagnostic modalities, and treatment options for emerging fungal, protozoan, helminthic, and ectoparasitic infections. It should be noted, however, that throughout this review we cite statistics documenting their increased incidence to back-up these infections as emerging, and although some of the diagnoses are clinical, others rely on newer laboratory tests, and the possibility exists that the increased incidence could be caused by better detection methods. [ABSTRACT FROM AUTHOR]

Ethanol oxidation reaction (EOR) is a promising substituent to the conventional oxygen evolution reaction (OER) for highly active and energy-saving hydrogen production. The rational design of bifunctional electrocatalysts to achieve ethanol-assisted water splitting is important, but still maintains challenge. Herein, we successfully synthesize a tungsten (W) doped cobalt molybdate nanosheet arrays on porous copper foam by one-step hydrothermal method (W–CoMoO 4 /CF). The synthesized W–CoMoO 4 /CF shows the morphology of neatly stacked cobblestone nanosheets with high surface area and improved reaction kinetics, leading to substantial bifunctional catalytic activity for EOR/hydrogen evolution reactions (HER). To reach a current density of 100 mA cm−2, only an overpotential of 102 mV is demanded when using W–CoMoO 4 /CF as an electrode for HER, while a potential of 1.40 V is required for EOR. Moreover, the ethanol-assisted water electrolyzer is constructed by using W–CoMoO 4 /CF as both anode/cathode, which requires a small total voltage of 1.54 V to achieve 100 mA cm−2 and could run steadily for 12 h, revealing its excellent application prospects. This study provides a promising guidance for the development of high-valence metal modified bimetallic oxides for hydrogen generation. A tungsten (W) doped cobalt molybdate nanosheet arrays is designed as bifunctional electrocatalyst for EOR and HER. The ethanol-assisted water electrolyzer delivers a small voltage of 1.54 V at 100 mA cm−2 and high stability for the generation of hydrogen fuel. [Display omitted] • The W element is successfully doped into the CoMoO 4 material by a simple one-step strategy. • The high surface area and improved reaction kinetics endow excellent bifunctional activity. • The ethanol-assisted water electrolyzer based on W–CoMoO 4 /CF exhibits small cell voltage and high stability. • The coupling effect of HER/EOR improved the generation rate of hydrogen fuel. [ABSTRACT FROM AUTHOR]

Abstract: Two new cyclic peptides, dianthins G–H (1 and 2), together with the known dianthin E (3), were isolated from the traditional Chinese medicinal plant Dianthus superbus. The sequences of cyclic peptides 1 and 2 were elucidated as cyclo (-Gly1-Pro2-Leu3-Thr4-Leu5-Phe6-) and cyclo (-Gly1-Pro2-Val3-Thr4-Ile5-Phe6-), on the basis of ESI tandem mass fragmentation analysis, extensive 2D NMR methods and X-ray diffraction. The isolated three compounds all increase proliferation of MC3T3-E1 cells in vitro using MTT method. [Copyright &y& Elsevier]

Abstract: Using the reference sequences of pgip genes in GenBank, a fragment of 930 bp covering the open reading frame (ORF) of rice Ospgip1 (Oryza sativa polygalacturonase-inhibiting protein 1) was amplified. The prokaryotic expression product of the gene inhibited the growth of Rhizoctonia solani, the causal agent of rice sheath blight, and reduced its polygalacturonase activity. Bioinformatic analysis showed that OsPGIP1 is a hydrophobic protein with a molecular weight of 32.8 kDa and an isoelectric point (pI) of 7.26. The protein is mainly located in the cell wall of rice, and its signal peptide cleavage site is located between the 17th and 18th amino acids. There are four cysteines in both the N- and C-termini of the deduced protein, which can form three disulfide bonds (between the 56th and 63rd, the 278th and 298th, and the 300th and 308th amino acids). The protein has a typical leucine-rich repeat (LRR) domain, and its secondary structure comprises α-helices, β-sheets and irregular coils. Compared with polygalacturonase-inhibiting proteins (PGIPs) from other plants, the 7th LRR is absent in OsPGIP1. The nine LRRs could form a cleft that might associate with proteins from pathogenic fungi, such as polygalacturonase. [Copyright &y& Elsevier]

We have studied the demagnetization behavior for melt-spun nanocomposite Pr8Fe87B5 ribbons in this paper. We have defined Hex which reflects the magnetic hardening of α-Fe and Hirr which expresses the irreversible reversal of magnetic hard phase. It is found that magnetization behavior can be well described using Hex and Hirr. A magnetic single-phase behavior is observed as Hirr approximately equals to Hex. Remanence enhancement is not only determined by the intergrain exchange coupling but also dominated by the anisotropy of Pr2Fe14B phase. To achieve a high energy product (BH)max, the ideal microstructure is discussed. The magnetic reversal in the ribbons is mainly controlled by inhomogeneous pinning of nucleated type. [Copyright &y& Elsevier]

• An evaluation method was used to assess eco-efficiency scores of 284 Chinese cities. • Spatio-temporal variations of the eco-efficiency scores of 284 cities were analyzed. • Transition effects of foreign direct investment (FDI) on eco-efficiency was examined. • FDI exhibits a pollution halo effect in the later stage of economic development. Foreign direct investment (FDI) has not only been considered to be an important economic engine to promote economic growth in China, but also has played a pivotal role in the ecological environment. Empirically, it may exhibit two conflicting effects, namely, pollution haven effect and pollution halo effect. Hence, it is of great significance of re-examine the effects of FDI on the ecological environment. To this end, we emphasize and identify the transition effects of FDI in the different stages of economic development. In this first step, we employed an extended data envelopment analysis (DEA) method to evaluate the eco-efficiency scores of 284 Chinese cities from 2005 to 2016, based on multi-source data including remote sensing image data and statistical data. In the second step, a panel smooth transition regression (PSTR) model was applied to explore the transition effects of FDI on eco-efficiency. The main findings are as follows. (1) The average eco-efficiency scores presented a U-shaped curve during the sample period. Specifically, it firstly declined from 2005 to 2013, and then the decreasing trend was reversed after 2013. (2) The results of spatial heterogeneity test showed that recently the Low-Low spatial clustering was mainly concentrated on the Central Plain urban agglomeration and the northwestern region while the High-High spatial clustering could be found in three regions, namely the Yangtze River urban agglomeration, the Pearl River Delta urban agglomeration, and the Chengdu-Chongqing urban agglomeration. (3) The results of the PSTR models revealed that FDI exhibited different effects on eco-efficiency in the different stages of economic development. Specifically, in the lower stage of economic level, FDI has a negative effect on eco-efficiency. The main reason could be the pollution haven effect. The rapid economic growth causes the increase in environmental awareness. Hence, when the economic level passed a certain threshold (about 79, 000 RMB), FDI contributed to the improvements of eco-efficiency scores, indicating that it became to exhibit the positive pollution halo effect. To conclude, the transition effects of FDI on eco-efficiency have been confirmed. Besides, we also observed that innovation capacity and education level were the foremost contributors to the enhancement of the eco-efficiency of Chinese cities. [ABSTRACT FROM AUTHOR]

• The new asymmetric nanochannel including two sections of the annulated channel and cylindrical channel is fabricated. • The highly positive charged molecules NAD+ transportation into membrane controlled by the redox reaction are explained. • The light-controlled ion current transportation property is discussed. In nature, ion transportation across cell membranes promotes the conduction of biological signals. Inspired by these gorgeous phenomena of nature, we construct a new artificial nanochannel membrane can well recurrence the ion transportation character of the biological ion pump by varying surface properties and present similar regulation mechanism by direct precisely controllable ion transportation. What counts is two separate channels including annulated and cylindrical channel, where the controllable translocation of ion influx across the membrane due to the change of surface charges and asymmetric structure. Notably, the mechanism of this system is that the highly positive charged molecules Nicotinamide adenine dinucleotide oxidized form cations (NAD+) are driven to into nanochannels membrane due to the redox reaction, which is carried out by an energy-transducing oxidoreduction from its reduced form (NADH) to product its oxidized form (NAD+) by O 2. As a light-controlled ion pump, this SiO 2 membrane system can selectively restrict NADH flux. Such a new ion pump could not only provide the emergence of an in-depth mechanistic understanding on smart ion pump behavior in living organism but also promotes the development of artificial ion pump devices in power source, seawater desalination and biosensor. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Revealing the mechanisms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry and cell-to-cell spread might provide insights for understanding the underlying mechanisms of viral pathogenesis, tropism, and virulence. The signaling pathways involved in SARS-CoV-2 entry and viral spike-mediated cell-to-cell fusion remain elusive. In the current study, we found that macropinocytosis inhibitors significantly suppressed SARS-CoV-2 infection at both the entry and viral spike-mediated cell-to-cell fusion steps. We demonstrated that SARS-CoV-2 entry required the small GTPase Rac1 and its effector kinase p21-activated kinase 1 by dominant-negative and RNAi assays in human embryonic kidney 293T-angiotensin-converting enzyme 2 cells and that the serine protease transmembrane serine protease 2 reversed the decrease in SARS-CoV-2 entry caused by the macropinocytosis inhibitors. Moreover, in the cell-to-cell fusion assay, we confirmed that macropinocytosis inhibitors significantly decreased viral spike-mediated cell-to-cell fusion. Overall, we provided evidence that SARS-CoV-2 utilizes a macropinocytosis pathway to enter target cells and to efficiently promote viral spike-mediated cell-to-cell fusion. [ABSTRACT FROM AUTHOR]

Nonviral vectors present considerable advantages over viral counterparts in gene transfer. However, the poor expression efficiency of the transfected genes poses a challenge for their use in gene therapy, primarily due to the inability of these vectors to overcome various barriers, including the biological barriers. Here, we report that ZNF511-PRAP1 may be involved in the recognition and inactivation of transfected plasmids. ZNF511-PRAP1 is induced by transfection of plasmid DNA and suppresses the transcription of transfected plasmids. It binds directly to the p21 promoter in transfected plasmids but not the endogenous counterpart. Similarly, ZNF511-PRAP1 suppresses the expression of the green fluorescent protein reporter gene on transiently transfected plasmids but not an integrated red fluorescence reporter gene with the same cytomegalovirus (CMV) promoter. Therefore, ZNF511-PRAP1 is able to differentiate between exogenous/nonintegrated and endogenous/integrated DNA. The suppression by ZNF511-PRAP1 is independent of DNA methylation and can be abolished by trichostatin A (TSA) treatment and knockdown of HDAC2 and/or ZNF511-PRAP1. Furthermore, ZNF511-PRAP1 interacts directly with HDAC2. Our results revealed that transfected plasmids are recognized by ZNF511-PRAP1 and suppressed by a repressor complex comprising ZNF511-PRAP1 and HDAC2 and suggest that ZNF511-PRAP1 could play a role as a potential molecular barrier in nonviral transgene expression. [ABSTRACT FROM AUTHOR]

Abstract: Nanostructured Pr8Fe86− x V x B6− y C y (x=0, 1; y=0, 1) ribbons composed of Pr2Fe14B and α-Fe phases with a high coercivity are fabricated by direct melt spinning. The effects of a single addition of V and a combined addition of V and C on the structures and magnetic properties of melt-spun Pr8Fe86VB6− x C x (x=0 and 1) ribbons have been investigated. Compared with addition-free ribbons, 1 at% V addition is found to reduce the grain sizes of the samples and improve their magnetic properties due to a strong exchange coupling between the hard and the soft phase. A remanence ratio of 0.82, a coercive field of 6.2kOe and a maximum energy product of 23.4MGOe in melt-spun Pr8Fe85VB6 ribbons are obtained at room temperature. The combined addition of V and C is found to lead to the formation of an intermediate phase of VC at grain boundaries, which appears as a pinning barrier during magnetization and results in an increase of the coercivity value to 6.9kOe for melt-spun Pr8Fe85VB5C ribbons. [Copyright &y& Elsevier]

Abstract: The influence of Cu and Mn substitution on the structure and magnetic properties of melt-spun Pr8Fe87−x B5M x ribbons with 0≤ x ≤1.2 was studied. The experimental results show that the Cu substitution of appropriate quantity leads to the c-axis alignment of Pr2Fe14B phase in melt-spun ribbons. The substitution of Mn improves magnetic properties of melt-spun Pr8Fe87−x B5Mn x ribbons, but does not show the same influences on the alignment of Pr2Fe14B phase as Cu substitution does. A remanence of 1.33T, a coercive field of 462kA/m and a maximum energy product of 185kJ/m3 in Pr8Fe86.4B5Mn0.6 ribbons are obtained at room temperature. [Copyright &y& Elsevier]

Smelting slags must be classified as a typical hazardous solid, which represents the most important point sources of potentially harmful elements. In addition, it can be known that particle sizes have been considered as an important indicator of human exposure risks. In this context, the present work mainly concerned about the potential leachability, bioavailability, bioaccessibility and mobility of toxic heavy metals in four zinc smelting slag fractions under the strong influences of mineralogical and morphological factors. The results indicated that heavy metals were mostly enriched in the smallest particles, with the higher metal concentrations of 3558.19 g/t for As, 123.49 g/t for Cd, 6757.57 g/t for Cu, 1.76% for Pb and 1.78% for Zn. Geochemical evaluation revealed that Cd, Cu, Mn, Pb and Zn was the most worrying elements, due to their unstable geochemical properties. Moreover, XRD and SEM-EDS results confirmed the formation of gypsum (CaSO 4 .2H 2 O) phase in 0.075–0.15 mm (SS3) and <0.075 mm (SS4) of the zinc smelting slags. The combined results of various characterization clearly showed the particle size distribution, surface morphological structure and mineral weathered state had a profound impact on the geochemical stability of heavy metals in the zinc smelting slags. These combined results of geochemical analysis and technical characterization could update our fundamental knowledge to better understand the mineralogical and morphological controls influencing the geochemical behaviors of heavy metals. Meanwhile, these study results would be of great scientific and realistic significance to develop effective targeted strategies for the subsequent pollution control and risk reduction of smelting wastes. [Display omitted] • Hazardous, microstructure and mineralogical characteristics were explored in depth. • Most metal concentrations increased with the size of smelting slag particles decreased. • Cd, Cu, Mn, Pb and Zn were at more risks based on the geochemical assessment results. • Geochemical behavior of smelting slag is mainly controlled by mineralogical and morphological factors. [ABSTRACT FROM AUTHOR]

Lepiota brunneoincarnata is a highly toxic mushroom species known to cause acute liver failure. However, there are limited reports investigating L. brunneoincarnata causing acute hepatic and renal damage. The present article reports 2 cases of L. brunneoincarnata poisoning in a mother and son from Chuxiong City, Yunnan Province, China. Both patients presented with gastrointestinal symptoms approximately 8–9 h after ingesting the suspect mushrooms and sought medical attention 27–28 h post-ingestion, both exhibiting acute hepatic and kidney injuries. Morphological and molecular biology studies confirmed the species of the mushrooms as L. brunneoincarnata. Liquid chromatography-tandem mass spectrometry analysis revealed mean fresh-weight concentrations of 123.5 μg/g α-amanitin and 45.7 μg/g β-amanitin in the mushrooms. The patients underwent standard treatments, including multiple-dose activated charcoal, oral silibinin capsules, N-acetylcysteine, penicillin G, hemoperfusion, and plasma exchange. One patient recovered completely and was discharged after 16 days of hospitalization. The other patient exhibited gradual improvement in liver and renal function; however, renal function deteriorated 9 days after ingestion, and the patient declined renal replacement therapy and returned home 14 days post-ingestion. The patient was then re-hospitalized due to oliguria and edema in both lower extremities. Renal biopsy revealed acute tubular necrosis, inflammatory cell infiltration, minor glomerular capsular fibrosis, loss of microvilli in the renal tubular epithelial cells, and interstitial edema. The patient underwent 2 rounds of continuous renal replacement therapy, which eventually resulted in improvement, and was discharged 31 days after mushroom consumption. It is noteworthy that this patient had already progressed to chronic kidney insufficiency 11 months after intoxication. [Display omitted] • Acute kidney injury without recovery following the ingestion of Lepiota brunneoincarnata has been rarely reported. • A renal biopsy was conducted in order to elucidate the features of kidney damage. • Mushrooms were identified as Lepiota brunneoincarnata by using morphology and molecular phylogeny. • Amanitins were detected from Lepiota brunneoincarnata by liquid chromatography-tandem mass spectrometry. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) pandemic represents a global threat, and the interaction between the virus and angiotensin-converting enzyme 2 (ACE2), the primary entry receptor for SARS-CoV-2, is a key determinant of the range of hosts that can be infected by the virus. However, themechanisms underpinning ACE2-mediated viral entry across species remains unclear. Using infection assay, we evaluated SARS-CoV-2 entry mediated by ACE2 of 11 different animal species. We discovered that ACE2 of Rhinolophus sinicus (Chinese rufous horseshoe bat), Felis catus (domestic cat), Canis lupus familiaris (dog), Sus scrofa (wild pig), Capra hircus (goat), and Manis javanica(Malayan pangolin) facilitatedSARS-CoV-2 entry into nonsusceptible cells. Moreover, ACE2 of the pangolin also mediated SARS-CoV-2 entry, adding credence to the hypothesis that SARS-CoV-2 may have originated frompangolins. However, the ACE2 proteins of Rhinolophus ferrumequinum (greater horseshoe bat), Gallus gallus (red junglefowl), Notechis scutatus (mainland tiger snake), or Mus musculus (house mouse) did not facilitate SARS-CoV-2 entry. In addition, a natural isoform of the ACE2 protein of Macaca mulatta (rhesus monkey) with the Y217N mutation was resistant to SARS-CoV-2 infection, highlighting the possible impact of this ACE2 mutation on SARSCoV-2 studies in rhesus monkeys. We further demonstrated that the Y217 residue of ACE2 is a critical determinant for the ability of ACE2 to mediate SARS-CoV-2 entry. Overall, these results clarify that SARS-CoV-2 can use the ACE2 receptors of multiple animal species and show that tracking the natural reservoirs and intermediate hosts of SARS-CoV-2 is complex. [ABSTRACT FROM AUTHOR]

Materials with Invar effect, i.e. zero thermal expansion (ZTE), have important applications in precision manufacturing. Here we report the emergence of Invar effect with excellent mechanical property by modulating electronic structure in LaFe 11.6-x Co x Si 1.4 , a family known for magnetocaloric effect. The observed linear thermal expansion coefficient (α l ∼ 1.5 × 10−8 K−1, 5–250 K, by XRD; α l ∼ 2.7 × 10−7 K−1, 109–250 K, by dilatometer) is superior to most other ZTE materials including the famous Invar alloy Fe 0.65 Ni 0.35. By taking advantage of distinct resolution ability of neutrons and X-rays to Fe/Co adjacent elements, the site occupancy of Co atoms was determined by joint refinements of neutron powder diffraction (NPD) and X-ray diffraction (XRD). On the basis, ab initio calculations were performed on the atomically resolved electronic band structure. The incorporation of Co atoms alters the electron transfer properties by increasing 3d bonding electrons at Co sub-lattice, as a result, spontaneous magnetostriction is inhibited and Invar effect prevails in the ferromagnetic region of LaFe 10.6 Co 1.0 Si 1.4. The electron local function (ELF) evidences the enhanced bonding strength and origin of excellent mechanical properties. The measured compressive strength can be up to ∼340 MPa, which endows the LaFe 10.6 Co 1.0 Si 1.4 good machining ability. Further, the mode-mode coupling coefficient b calculated from density of states (DOS) explains the evolution of phase transition order with Co doping, which gives LaFe 10.6 Co 1.0 Si 1.4 a significant advantage in its effective cooling capacity under low magnetic fields. The present study provides a solid foundation for exploiting multifunctional application of La(Fe,Si) 13 alloys with Co incorporation from the perspective of electronic structure modulation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Dihydroartemisinin (DHA), one of the main metabolites of artemisinin and its derivatives, presents anti-cancer potential in vitro and in vivo. To explore the mechanisms of resistance toward DHA, a DHA-resistant cell line, HeLa/DHA, was established with a resistance factor of 7.26 in vitro. Upon DHA treatment, apoptotic cells were significantly elicited in parental HeLa cells but minimally induced in HeLa/DHA cells. HeLa/DHA cells also displayed much less sensitivity to DHA-induced tumor suppression in cancer xenograft models than HeLa cells. Intriguingly, DHA-resistant cells did not display a multidrug-resistant phenotype. Based on a proteomic study employing LC–ESI–MS/MS together with pathway analysis, DJ-1 (PARK7) was found to be highly expressed in HeLa/DHA cells. Western blot and immunofluorescence assays confirmed the higher expression of DJ-1 in HeLa/DHA cells than in parental cells in both cell line and xenograft models. DJ-1 is translocated to the mitochondria of HeLa/DHA cells and oxidized, providing DJ-1 with stronger cytoprotection activity. Further study revealed that DJ-1 knockdown in HeLa/DHA cells abolished the observed resistance, whereas overexpression of DJ-1 endowed the parental HeLa cells with resistance toward DHA. Reactive oxygen species (ROS) were also significantly induced by either DHA or hydrogen peroxide in HeLa cells but not in resistant HeLa/DHA cells. When the cells were pretreated with N-acetyl-l-cysteine, the effect of DJ-1 knockdown on sensitizing HeLa/DHA cells to DHA was significantly attenuated. In summary, our study suggests that overexpression and mitochondrial translocation of DJ-1 provides HeLa/DHA cells with resistance to DHA-induced ROS and apoptosis. [Copyright &y& Elsevier]

Abstract: LaFe11.83Si1.17 compound shows a first-order transition from paramagnetic to ferromagnetic state. When measurement is carried out from low to high temperature in an increasing field, there is a spike of 51J/kgK at 174.8K, followed by a plateau of 20J/kgK in the curve of entropy change versus temperature determined by the Maxwell relation. However, the nature of the spike is fictitious, which is caused by an obvious superheat of the ferromagnetic state when the Maxwell relation or the Clausius–Clapeyron equation is used to evaluate the entropy change. [Copyright &y& Elsevier]

Quercetin, a dietary-derived flavonoid, suppresses tumor growth in vitro and in vivo, and inhibits the activity of tyrosine kinase. The effects of quercetin on the angiogenic process were examined in this study. Quercetin was found to inhibit several important steps of angiogenesis including proliferation, migration, and tube formation of human microvascular dermal endothelial cells in a dose-dependent manner. Additionally, the effect of quercetin on endothelial cell proliferation was confirmed using human umbilical vein endothelial cells. The activity of quercetin on the proliferation of endothelial cells was stronger than that on A549, BEL-7402, MKN-45 tumor cells and NIH-3T3 fibroblast cells. The chicken chorioallantoic membrane assay revealed that addition of quercetin displayed an antiangiogenic effect in vivo. After exposure to quercetin, a decrease in the expression and activity of matrix metalloproteinase-2, which is involved in the angiogenic process of migration, invasion, and tube formation, was observed by reverse transcription-polymerase chain reaction (RT-PCR) and gelatin zymography. These findings suggest that quercetin has antiangiogenic potential and that this effect may be related to an influence on the expression and activity of matrix metalloproteinase-2. [Copyright &y& Elsevier]