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Rapid screening of foodborne pathogens is of great significance to ensure food safety. A microfluidic biosensor based on immunomagnetic separation, enzyme catalysis and electrochemical impedance analysis was developed for rapid and sensitive detection of Salmonella typhimurium. First, the bacterial sample, the magnetic nanoparticles (MNPs) modified with capture antibodies, and the enzymatic probes modified with detection antibodies and glucose oxidase (GOx) were simultaneously injected into the microfluidic chip, followed by mixing and incubation to form MNP-bacteria-probe sandwich complexes. Then, glucose with high impedance was injected into the chip and catalyzed by the GOx on the complexes into hydrogen peroxide with high impedance and gluconic acid with low impedance, which was finally measured using the low-cost interdigitated microelectrode and the electrochemical impedance analyzer to determine the target bacteria. Under the optimal conditions, this biosensor could quantitatively detect Salmonella typhimurium at the concentrations from 1.6 × 102 CFU/mL to 1.6 × 106 CFU/mL in 1 h with the low detection limit of 73 CFU/mL. Besides, this biosensor was demonstrated with good feasibility for practical applications by detecting the Salmonella typhimurium spiked chicken meat samples.

PDF file - 48K, Inhibiting IRAK-1/-4 abrogates the effects of TLR1-TLR2 agonist in melanoma cells

PDF file - 49K, Role of TLR-induced cytokines and NF-kB on cell survival

PDF file - 66K, Apoptosis-related gene transcription array of A375 melanoma cells following IRAK inhibition with or without vinblastine

PDF file - 77K, Overexpressing IRAK-1 in melanoma cells augments the expression of various cytokines and chemokines

PDF file - 144K, Effects of TLR stimulation and cytokines on IRAK phosphorylation in melanoma cells

Foodborne pathogenic bacteria have been considered as a major risk factor for food safety. It is of great significance to carry out in-field screening of pathogenic bacteria to prevent the outbreaks of foodborne diseases. In this study, a portable lab-on-a-disc platform with a microfluidic disc was developed for rapid and automatic detection of Salmonella typhimurium using a nickel nanowire (NiNW) net for effective separation of target bacteria, horseradish peroxidase nanoflowers (HRP NFs) for efficient amplification of biological signals, and a self-developed smartphone APP for accurate analysis of colorimetric images. First, the microfluidic disc was preloaded with reagents and samples and centrifuged to form one bacterial sample column, one immune NiNW column, one HRP NF column, two washing buffer columns and one tetramethylbenzidine (TMB) column, which were separated by air gaps. Then, a rotatable magnetic field was specifically developed to assemble the NiNWs into a net, which was automatically controlled by a stepped motor to successively pass through the sample column for specific capture of target bacteria, the HRP NF column for specific label of target bacteria, the washing columns for effective removal of sample background and non-specific binding NFs, and the TMB column for colorimetric determination of target bacteria. The color change of TMB from colorless to blue was finally analyzed using the smartphone APP to quantitatively determine the target bacteria. This lab-on-a-disc platform could detect Salmonella typhimurium from 5.6 × 101 CFU/20 μL to 5.6 × 105 CFU/20 μL in 1 h with a lower detection limit of 56 CFU/20 μL. The recovery of target bacteria in spiked chicken samples ranged from 97.5% to 101.8%. This portable platform integrating separation, labeling, washing, catalysis and detection onto a single disc is featured with automatic operation, fast reaction, and small size and has shown its potential for in-field detection of foodborne pathogens.

A catastrophic rockslide occurred on 7 February 2021 in Chamoli area in the high Himalaya. In the absence of field data, multiple satellites data of decade span have been used to investigate and understand the progressive destabilization of rockslide body. A 3D geometric model was developed using geospatial information about geology, terrain, and ice cover to understand the triggering mechanism. Several causes are uncovered as: the pronounced long-term change of land surface temperature facilitated local permafrost degradation and led to ice cover shrinking since 2010; the occurrence of ice avalanche nearby in 2016 accompanying with sidewall-to-bedrock fracturing enhanced the ice segregation beneath the rockslide body; and the development of side cracks in early February 2021 led to dropping of side support and percolating of surface water. Heavy precipitation several days before favoured the destabilization, top-corner cracks developing and top-side bergschrund breaking abruptly two days before, and ice strength reduction owing air temperature rising few hours before the event triggered finally the rockslide. The frequent disasters such as cloudburst, extreme precipitation, landslides, and snow avalanches responding to global warming and climate change in the Himalayan region needs immediate attention to the chain-like geohazards and collaborative observation with satellites and other platforms.

A novel colorimetric biosensor was explored for fast, sensitive, and on-site detection of Salmonella on a microfluidic chip employing immune gold@platinum nanoparticles (Au@Pt NPs) for specific bacterial labeling, a finger-driven mixer with two serial air chambers for efficient immunoreaction and a nuclear track membrane as specific-size microfilter for effective bacterial isolation from excessive immune Au@Pt NPs. First, the bacterial sample and immune Au@Pt NPs were pipetted into the mixing chamber and mixed sufficiently through repeated press-release actions on the small air chamber which could precisely control the air volume, leading to the formation of bacteria-immune Au@Pt NP conjugates. Then, the small and large air chambers were pressed simultaneously to push all the solution in the mixing chamber to flow through the microfilter for trap of the formed larger-size conjugates on the membrane and removal of the unbound smaller-size immune Au@Pt NPs. After the H

Earthquakes are one of the most threatening natural disasters to human beings, and pre- and post-earthquake microwave brightness temperature (MBT) anomalies have attracted increasing attention from geosciences as well as remote sensing communities. However, there is still a lack of systematic description about how to extract and then discriminate the authenticity of seismic MBT anomalies. In this research, the first strong earthquake occurring near the northern edge of eastern Bayan Har block in nearly 20 years, the recent Mw 7.3 Maduo earthquake in Qinghai province, China on 21 May 2021, was selected as a case study. Based on the monthly mean background of MBT, the spatiotemporal features of MBT residuals with 10.65 GHz before and after the earthquake was firstly revealed. Referring to the spatial patterns and abnormal amplitudes of the results, four typical types of evident MBT positive residuals were obtained, and the time series of intensity features of each category was also quantitatively analyzed. Then, as the most influential factor on surface microwave radiation, air temperature, soil moisture and precipitation were analyzed to discriminate their contributions to these residuals. The fourth one, which occurred north to the epicenter after the earthquake, was finally confirmed to be caused by soil moisture reduction and thus ruled out as being related to seismicity. Therefore, the three retained typical MBT residuals with 10.65 GHz could be identified as possible anomalies associated with the Maduo earthquake, and were further analyzed collaboratively with some other reported abnormal phenomena related to the seismogenic process. Furthermore, through time series analysis, the MBT positive residuals inside the Bayan Har block were found to be more significant than that outside, and the abnormal behaviors of MBT residuals in the elevation range of 4000–5000 m reflected the shielding effect on microwave radiation from thawing permafrost on the plateau in March and April, 2021. This research provides a detailed technique to extract and discriminate the seismic MBT anomaly, and the revealed results reflect well the joint effect of seismic activity and regional coversphere environment on satellite-observed MBT.

Thaumatin-like protein-1 (TLP-1), a protein displaying high polyphenol oxidase (PPO) action and a member of the pathogenesis-related (PR) protein family, has a considerable influence on the enzymatic browning of

The NASICON-type Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 electrolytes were synthesized by a facile aqueous-based sol-gel process with alcohols free. Compared with the samples prepared by solid-state reaction, the modified sol-gel derived Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 electrolyte exhibited a rhombohedral crystal symmetry without impurity phase and higher ionic conduction behavior. After sintered at 850 °C for 5 h, the sol-gel specimen showed a total ionic conductivity of 3.1 × 10 − 4 S/cm at 30 °C and 1.0 × 10 − 3 S/cm at 60 °C. In addition, the chemical and phase stability of the as-prepared Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 with three types of cathode materials (i.e. LiNi 0.8 Co 0.15 Al 0.05 O 2 , LiNi 0.5 Mn 1.5 O 4 and Li 3 V 2 (PO 4 ) 3 ) was investigated in the temperature range of 500 to 700 °C. This work proposes a synthesis choice for Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 , and also favors to the electrode identification for all-solid-state lithium secondary battery using NASICON-type electrolyte.

Objective. To observe the curative effect of VAWI on Xinjiang Uygur patients with silicosis fibrosis.Methods. After we diagnosed the 40 patients with the first phase of silicosis, we randomly divided them into two groups: the basic treatment group (group A,n=20) and the VAWI group (group B,n=20). At the same time, we selected the age-matched healthy patients (n=20). We applied the combined protein chip with SELDI-TOF-MS to carry out the serum analysis. The data were analyzed throughout data preprocessing, difference in PEAK screening, hierarchical cluster analysis, and Principal Component Analysis (PCA). We built decision tree model and predict the difference between the PEAK corresponding proteins.Results. The proteins peaks corresponding to name, predicted protein, and gene name were as follows: M2001_69, amyloid beta a4 protein, APP, and M2017_02, amyloid beta a4 protein, APP. The different expression of proteins in patients with silicosis was found before and after with VAWI treatment. The predicted proteins were as follows: M1982_50, amyloid beta a4 protein, APP; M3164_50, fibrinogen alpha chain frag, FGA; M3379_28, fibrinogen alpha chain frag, FGA; and so on.Conclusion. VAWI presented curative effect on patients with silicosis fibrosis via the alternation of proteins expression in serum.

Ordered porous cabon with a 2-D hexagonal structure, high specific surface area and large pore volume was synthesized through a two-step heating method using tri-block copolymer as template and phenolic resin as carbon precursor. The results indicated the electrochemical performance of the sulfur/carbon composites prepared with the ordered porous carbon was significantly affected by the pore structure of the carbon. Both the specific capacity and cycling stability of the sulfur/carbon composites were improved using the bimodal micro/meso-porous carbon frameworks with high surface area. Its initial discharge capacity can be as high as 1200 mAh·g−1 at a current density of 167.5 mA·g−1. The improved capacity retention was obtained during the cell cycling as well.

Generic Escherichia coli was isolated from surface water and groundwater samples from two dairies in Northern California and tested for susceptibility to antibiotics. Surface samples were collected from flush water, lagoon water, and manure solids, and groundwater samples were collected from monitoring wells. Although E. coli was ubiquitous in surface samples with concentrations ranging from several hundred thousand to over a million colony-forming units per 100 mL of surface water or per gram of surface solids, groundwater under the influence of these high surface microbial loadings had substantially fewer bacteria (3- to 7-log10 reduction). Among 80 isolates of E. coli tested, 34 (42.5 %) were resistant to one or more antibiotics and 22 (27.5 %) were multi-antibiotic resistant (resistant to ≥3 antibiotics), with resistance to tetracycline, cefoxitin, amoxicillin/clavulanic acid, and ampicillin being the most common. E. coli isolates from the calf hutch area exhibited the highest levels of multi-antibiotic resistance, much higher than isolates in surface soil solids from heifer and cow pens, flush alleys, manure storage lagoons, and irrigated fields. Among E. coli isolates from four groundwater samples, only one sample exhibited resistance to ceftriaxone, chloramphenicol, and tetracycline, indicating the potential of groundwater contamination with antibiotic-resistant bacteria from dairy operations.

As the oxidation and chromium volatilization of chromia-forming alloy interconnects can cause Solid oxide fuel cells (SOFC) cathode poisoning and cell degradation, spinel coatings like Mn1.5Co1.5O4 have been applied as a barrier to oxygen and chromium diffusion. To evaluate their long-term stability, the properties of the reaction layer between the Mn1.5Co1.5O4 coating and Cr2O3 scale formed on the alloy surface need to be characterized. Therefore, compositions of Mn1.5−0.5xCo1.5−0.5xCrxO4 (x = 0–2) were prepared to investigate their electrical properties, cation distributions, and thermal expansion behavior at high temperature. With increasing Cr content in manganese cobalt spinel oxides, the cubic crystal structure is stabilized and the electrical conductivity and coefficient of thermal expansion both decrease. The cation distributions determined from neutron diffraction show that Cr and Mn have stronger preference for octahedral sites in the spinel structure as compared with Co.

Spinel oxide ceramic coatings have been shown effective to reduce oxidation rate and chromium volatilization of ferritic stainless steels SOFC interconnect. In this work, the effects of transition metal (TM) doping in (Mn,Co)3O4 (TM=Fe) spinels on the reaction with chromia and electrical conductivity at high temperature were studied. Iron additions lead to a decrease in conductivity, but do not increase the extent of reaction except for the higher Fe content of 0.7 in MnCo2-xFexO4. Even at this highest Fe content, Fe was not present in the high-chromium reaction layer.

Erythropoiesis, the production of red blood cells, must be tightly controlled to ensure adequate oxygen delivery to tissues without causing thrombosis or stroke. Control of physiologic and pathologic erythropoiesis is dependent predominantly on erythropoietin (EPO), the expression of which is regulated by hypoxia-inducible factor (HIF) activity in response to low oxygen tension. Accumulating evidence indicates that oxygen-independent mediators, including inflammatory stimuli, cytokines, and growth factors, also upregulate HIF activity, but it is unclear whether these signals also result in EPO production and erythropoiesis in vivo. Here, we found that signaling through herpesvirus entry mediator (HVEM), a molecule of the TNF receptor superfamily, promoted HIF-1α activity in the kidney and subsequently facilitated renal Epo production and erythropoiesis in vivo under normoxic conditions. This Epo upregulation was mediated by increased production of NO by renal macrophages. Hvem-deficient mice displayed impaired Epo expression and aggravated anemia in response to erythropoietic stress. These data reveal that HVEM signaling functions to promote HIF-1α activity and Epo production, and thus to regulate erythropoiesis. Furthermore, our findings suggest that this molecular mechanism could represent a therapeutic target for Epo-responsive diseases, including anemia.

Manganese cobalt oxides are promising coating materials for reducing chromium volatilization, and thus the associated cathode poisoning, from interconnect alloys in solid oxide fuel cells (SOFCs). Interaction between this coating and the oxide scale formed on the alloy during fuel cell operation can lead to changes in the coating composition and thus its performance. In this study, the properties of manganese cobalt spinel oxides and the reaction between manganese cobalt spinel oxides and chromia were investigated. The reaction product consists of two layers: a layer in contact with chromia that grows by the diffusion of cobalt and manganese from (Mn,Co)3O4 toward the chromia and an intermediate layer that grows by the diffusion of chromium through the reaction layer. The effect of dopants on the coating performance was also investigated. With the addition of iron or titanium, the rate of reaction between the spinel coating and the chromia scale can be decreased significantly, which would reduce the risk of scale spallation and provide an increase in the lifetime of the interconnect and thus the fuel cell.

A challenge in the long term operation of solid oxide fuel cells (SOFCs) is minimizing degradation due to chromium poisoning of the cathode. One approach is to apply a ceramic coating to the interconnect to minimize chromium volatilization and the associated detrimental effect on fuel cell performance. In this work the long-term stability of spinel oxide coatings for use in SOFCs has been evaluated. In particular, results on the interaction between chromia and the coating materials will be presented. To evaluate the impact of the reaction layer on cell performance, bulk analogues of the relevant composition have been prepared to allow for measurement of the relevant properties, such as electrical conductivity and coefficient of thermal expansion. The effect of changing the coating composition, in particular with the addition of iron or titanium, on the interaction and properties has also been evaluated. The results indicate that the performance of manganese cobalt oxide coatings can be improved with the addition of iron or titanium.

B and T lymphocyte attenuator (BTLA) is a coinhibitory receptor that interacts with herpesvirus entry mediator (HVEM), and this interaction regulates pathogenesis in various immunologic diseases. In graft-versus-host disease (GVHD), BTLA unexpectedly mediates positive effects on donor T-cell survival, whereas immunologic mechanisms of this function have yet to be explored. In this study, we elucidated a role of BTLA in GVHD by applying the newly established agonistic anti-BTLA monoclonal antibody that stimulates BTLA signal without antagonizing BTLA-HVEM interaction. Our results revealed that provision of BTLA signal inhibited donor antihost T-cell responses and ameliorated GVHD with a successful engraftment of donor hematopoietic cells. These effects were dependent on BTLA signal into donor T cells but neither donor non-T cells nor recipient cells. On the other hand, expression of BTLA mutant lacking an intracellular signaling domain restored impaired survival of BTLA-deficient T cells, suggesting that BTLA also serves as a ligand that delivers HVEM prosurvival signal in donor T cells. Collectively, current study elucidated dichotomous functions of BTLA in GVHD to serve as a costimulatory ligand of HVEM and to transmit inhibitory signal as a receptor.

T-cell tolerance is the central program that prevents harmful immune responses against self-antigens, in which inhibitory PD-1 signal given by B7-H1 interaction plays an important role. Recent studies demonstrated that B7-H1 binds CD80 besides PD-1, and B7-H1/CD80 interaction also delivers inhibitory signals in T cells. However, a role of B7-H1/CD80 signals in regulation of T-cell tolerance has yet to be explored. We report here that attenuation of B7-H1/CD80 signals by treatment with anti–B7-H1 monoclonal antibody, which specifically blocks B7-H1/CD80 but not B7-H1/PD-1, enhanced T-cell expansion and prevented T-cell anergy induction. In addition, B7-H1/CD80 blockade restored Ag responsiveness in the previously anergized T cells. Experiments using B7-H1 or CD80-deficient T cells indicated that an inhibitory signal through CD80, but not B7-H1, on T cells is responsible in part for these effects. Consistently, CD80 expression was detected on anergic T cells and further up-regulated when they were re-exposed to the antigen (Ag). Finally, blockade of B7-H1/CD80 interaction prevented oral tolerance induction and restored T-cell responsiveness to Ag previously tolerized by oral administration. Taken together, our findings demonstrate that the B7-H1/CD80 pathway is a crucial regulator in the induction and maintenance of T-cell tolerance.

The La0.85Sr0.15Cr0.95Ni0.02Co0.02O3 (LSC) interconnect materials for solid oxide fuel cells (SOFCs) were synthesized by EDTA–citrate complexing method. Thermal decomposition behavior of the gel, phase formation and morphology of LSC powders were characterized by thermogravimetry/differential thermal (DSC/TG) analysis, X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. It appeared that lower pH value (pH 4.9) of the precursor solution resulted in a transient liquid phase, SrCrO4, in the calcined LSC powder. The sintering characteristics, electrical conductivity and thermal expansion properties of sintered bars were investigated. La0.85Sr0.15Cr0.95Ni0.02Co0.02O3 prepared in the condition of pH 4.9 showed an electrical conductivity of 15.6 S cm−1 at 800 °C and a thermal expansion coefficient (TEC) of 10.8 × 10−6 K−1 (20–900 °C), which is suitable for use as interconnect materials for SOFCs.

Alkaline earth metals (Ca, Sr, Ba) substituted lanthanum copper oxides were investigated to evaluate their potentials as cathode materials for intermediate temperature solid oxide fuel cell (IT-SOFC). The crystal structure, thermal expansion and electrochemical performance of La1−xAExCuO3−δ (x = 0.3, AE=Ca, Sr, Ba) were studied by X-ray diffraction, thermal dilatometer and impedance spectra, respectively. By lowering the size of the A-site cation in ABO3 perovskite, a lower thermal expansion and polarization resistance were obtained forCa-doped LaCuO3−δ cathode which showed an area specific resistance of 0.19 Ω cm−2 under open circuit potential conditions at 800°C, and a polarization overpotential of 52 mV at a current density of 0.1 A/cm2 at 700°C, being a potential candidate of cathode material for IT-SOFCs.

The effects of cation substitution on the sintering characteristics, thermal expansion and electrical conductivity properties of La(AE)Cr(M)O 3 (AE Mg, Ca, Sr, M Ni, Cu, Co) were investigated. The sinterability of alkaline metal earth (AE)-doped LaCrO 3 increased with AE contents in a sequence of Ca > Sr > Mg. Sr-doped LaCrO 3 sample had a TEC compatible with that of 8YSZ electrolyte. The transition metals of Ni, Co and Cu substituted in Cr-site further optimized the sinterability of La 0.85 Sr 0.15 CrO 3 in air. Ni and Co could effectively enhance the electrical conductivity from room temperature to 1123 K though the concomitant increase in TEC was distinctively large with Co doping. The TEC was controlled by co-doping Ni and Co in Cr-site, and La 0.85 Sr 0.15 Cr 0.95 Ni 0.02 Co 0.02 O 3 exhibited a TEC of 10.9 × 10 −6 /K, which was matched with that of 8YSZ, indicating that it could be suitable to be used as an SOFC interconnect material.

Toll-like receptors (TLR) are expressed by a variety of cancers, including melanoma, but their functional contributions in cancer cells are uncertain. To approach this question, we evaluated the effects of stimulating or inhibiting the TLR/IL-1 receptor-associated kinases IRAK-1 and IRAK-4 in melanoma cells where their functions are largely unexplored. TLRs and TLR-related proteins were variably expressed in melanoma cell lines, with 42% expressing activated phospho-IRAK-1 constitutively and 85% expressing high levels of phospho-IRAK-4 in the absence of TLR stimulation. Immunohistochemical evaluation of melanoma tumor biopsies (n = 242) revealed two distinct patient populations, one that expressed p-IRAK-4 levels similar to normal skin (55%) and one with significantly higher levels than normal skin (45%). Levels of p-IRAK-4 levels did not correlate with clinical stage, gender, or age, but attenuated IRAK-1,-4 signaling with pharmacologic inhibitors or siRNA-enhanced cell death in vitro in combination with vinblastine. Moreover, in a xenograft mouse model of melanoma, the combined pharmacologic treatment delayed tumor growth and prolonged survival compared with subjects receiving single agent therapy. We propose p-IRAK-4 as a novel inflammation and prosurvival marker in melanoma with the potential to serve as a therapeutic target to enhance chemotherapeutic responses. Cancer Res; 72(23); 6209–16. ©2012 AACR.

Reduction in the operating temperature of solid oxide fuel cells (SOFCs) allows for the use of ferritic stainless steels as the interconnect material. However, cathode poisoning due to volatilization of chromium from the oxide scale formed on these alloys requires the use of a ceramic coating on the alloy. The reaction layer formed between the coating and the alloy affects the performance of the fuel cell, so the composition and properties of this layer must be considered in selecting the alloy and coating compositions. In this paper, the factors relevant to selection of the alloy/coating materials and the effect of the alloy-coating interaction on these factors are discussed.

Author(s): Jay-Russell, Michele T.; Montfort, Jordi; Liu, Yingjia; Huang, Stephanie; Gorski, Lisa; Cooley, Michael; Mandrell, Robert; Wheeler, Jessica; Reis, Dawn; Li, Xunde; Atwill, Edward R. | Abstract: Captive amphibians and reptiles are well-documented sources of human salmonellosis through direct contact with contaminated feces or fomites. However, the relative significance of wild cold-blooded vertebrates as hosts/reservoirs of zoonotic enteric pathogens in their natural habitat is not known. Wild amphibian and reptile populations are present in the leafy green produce production environment in the central California coast, and there are reports from growers that frogs and other species sometimes intrude into produce fields. These intrusions may result in destruction of the crop and economic losses, due to food safety and quality concerns. Environmental groups have also noted potential conflicts between conservation efforts and food safety practices that result in removal or damage to aquatic habitat (e.g., farm ponds, adjacent wetland areas). To address these concerns, we conducted a survey of foodborne pathogen prevalence in common amphibian and reptile populations during the 2011 produce growing season in the central California coast. Preliminary results indicate that Salmonella prevalence was higher among wild-caught reptile (33%) compared with amphibian (4%) taxa. In contrast, all samples were negative for E. coli O157. Wildlife damage management in fresh produce production fields is challenging, due to the diversity of potential hosts/reservoirs of foodborne pathogens and a limited number of mitigation strategies. Professionals working in vertebrate pest control could play an important role in assisting fresh produce growers with implementation of co-management approaches that promote public health and conservation goals in the central coast agricultural landscape.

In the title compound, C15H12N4·H2O, the organic molecule displays approximate non-crystallographic twofold symmetry: the dihedral angle between the benzimidazole ring systems is 81.37 (12)°. In the crystal, the components are linked by O—H...N hydrogen bonds, forming chains propagating in [101]. Aromatic π–π stacking [centroid–centroid separation = 3.595 (2) Å] helps to consolidate the structure.