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A friction stir vibration processing (FSVP) with different vibration frequencies (20 Hz, 40 Hz, and 80 Hz) was employed for the fabrication of AZ70/ZrO2–CeO2 surface composite with the aim of improving mechanical and wear performance. Thus, the influence of vibration frequency as a vital parameter on the microstructure and reinforcement distribution, shear punch strength (SPT), and wear behavior of the composites was investigated. The results indicated that the material flow, agglomeration of particles, and dislocation density were influenced by the increasing vibration frequency that can be contributed to the successive mechanical stirring-assisted plastic deformation/strain and further grain refinement. It was also demonstrated that when vibration frequency was increased, the shear punch strength (by about 34%) and wear resistance (by about 44%) of the developed composites improved. [ABSTRACT FROM AUTHOR]

The present study was conducted to develop a green process that provides access to the development of Schiff base derivatives of chitosan with the heterocyclic moiety as a novel class of anti-gastric cancer agent. In the present study, we have synthesized these derivatives by reacting various pyrazoles with chitosan using CAN in PEG400. The compounds were synthesized in 20 min in excellent yield by using CAN at 5% in PEG400 at 80°C in the shortest reaction time of 20 min. The PEG400 could be efficiently recycled for the three consecutive runs. The developed compounds were tested for EGFR-TK inhibition using a Kinase-Glo Plus luminescence kinase assay kit where they exhibited significant activity revealing compound 2d as the most potent analog, while other compounds showed mild to moderate inhibitory activity. MTT assay was conducted to determine the effect of the three most potent EGFR inhibitors (2b, 2c, and 2d) on the proliferation of gastric cancer cells (SGC-7901). The results showed compound 2d as the most potent anticancer agent against SGC7901 cells. The effect of compound 2d was also quantified on the apoptosis and cell phase of SGC7901 cells using flow cytometry assay at various concentrations ranging from 0, 10, 20, and 30 µM. Results suggest that compound 2d showed significant inhibition of SGC-7901 by inducing apoptosis and arresting G0/G1 cell phase. The western blot analysis also revealed that compound 2d significantly inhibited the overexpression of EGFR in SGC-7901 cells. The study successfully demonstrated the development of N‑pyrazole amino chitosan as a novel class of agent against gastric cancer via inhibition of EGFR. [ABSTRACT FROM AUTHOR]

Sorption-based atmospheric water harvesting has the potential to realize water production anytime, anywhere, but reaching a hundred-gram high water yield in semi-arid climates is still challenging, although state-of-the-art sorbents have been used. Here, we report a portable and modularized water harvester with scalable, low-cost, and lightweight LiCl-based hygroscopic composite (Li-SHC) sorbents. Li-SHC achieves water uptake capacity of 1.18, 1.79, and 2.93 g g−1 at 15%, 30%, and 60% RH, respectively. Importantly, considering the large mismatch between water capture and release rates, a rationally designed batch processing mode is proposed to pursue maximum water yield in a single diurnal cycle. Together with the advanced thermal design, the water harvester shows an exceptional water yield of 311.69 g day−1 and 1.09 g gsorbent−1 day−1 in the semi-arid climate with the extremely low RH of ~15%, demonstrating the adaptability and possibility of achieving large-scale and reliable water production in real scenarios. Sorption-based atmospheric water harvesting has the potential to realize flexible water production but reaching high water yield in semi-arid climate is still challenging. Here, the authors report a portable and modularized water harvester with scalable, low-cost, and lightweight hygroscopic composite sorbent which shows an exceptional water production in semi-arid climate with low relative humidity of 15%. [ABSTRACT FROM AUTHOR]

Due to the high specific capacity and energy density, lithium-sulfur batteries have been recognized as the most promising energy storage devices for electric vehicles. However, they are also faced with some problems, such as poor electronic conductivity and severe polysulfide migration. In this work, hierarchical porous carbons (HPCs) are prepared and developed as sulfur host materials in the lithium-sulfur batteries. Due to the hierarchical porous structure, the element sulfur can be uniformly dispersed into the HPCs. Besides, the unique structure also can promote the electron transport and inhibit the polysulfide migration. Based on these advantages, the as-prepared HCPs/S cathode exhibits superior electrochemical performance, including high capacity, excellent rate capability, and stable long-term cycling performance. This work provides a facile way to prepare the sulfur host materials for high-performance lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

Rational design of host materials for element sulfur is critical in the lithium-sulfur batteries to stabilize the polysulfide, which could migrate from the cathode to the anode, leading to the so-called shuttle effect. Herein, we develop a method to prepare the suitable sulfur host materials for the lithium-sulfur batteries. The manganese dioxide nanospheres are successfully prepared and designed as sulfur host in the lithium-sulfur batteries. The as-prepared manganese dioxide/S composites could be formed flexible and self-supported electrode without the current collector. Due to the presence of the manganese dioxide/S composites, the lithium-sulfur batteries exhibit superior electrochemical performance, including high specific capacity, stable cycling performance, and excellent rate performance. [ABSTRACT FROM AUTHOR]

The rechargeable lithium-sulfur battery is an attractive energy storage device due to the high specific capacity and high energy density. The wide application of lithium-sulfur batteries, however, is hindered owing to the rapid capacity fading caused by the polysulfide dissolution and migration between the cathode and anode side. Herein, we demonstrate a new strategy to address the severe problem of polysulfide migration during the electrochemical cycles by designing titanium carbide nanosheets/S hybrid composites. In this unique hybrid structure, the titanium carbide nanosheets could provide fast lithium-ion and electron paths and keep structural stability during the cycles. Moreover, the space of the titanium carbide nanosheets acts as binding sites for trapping polysulfide. As a result, the hybrid titanium carbide nanosheets/S composites exhibit high performance with specific capacity, rate capability, and cycling stability. [ABSTRACT FROM AUTHOR]

The emergency use authorization of two mRNA vaccines in less than a year from the emergence of SARS-CoV-2 represents a landmark in vaccinology1,2. Yet, how mRNA vaccines stimulate the immune system to elicit protective immune responses is unknown. Here we used a systems vaccinology approach to comprehensively profile the innate and adaptive immune responses of 56 healthy volunteers who were vaccinated with the Pfizer–BioNTech mRNA vaccine (BNT162b2). Vaccination resulted in the robust production of neutralizing antibodies against the wild-type SARS-CoV-2 (derived from 2019-nCOV/USA_WA1/2020) and, to a lesser extent, the B.1.351 strain, as well as significant increases in antigen-specific polyfunctional CD4 and CD8 T cells after the second dose. Booster vaccination stimulated a notably enhanced innate immune response as compared to primary vaccination, evidenced by (1) a greater frequency of CD14+CD16+ inflammatory monocytes; (2) a higher concentration of plasma IFNγ; and (3) a transcriptional signature of innate antiviral immunity. Consistent with these observations, our single-cell transcriptomics analysis demonstrated an approximately 100-fold increase in the frequency of a myeloid cell cluster enriched in interferon-response transcription factors and reduced in AP-1 transcription factors, after secondary immunization. Finally, we identified distinct innate pathways associated with CD8 T cell and neutralizing antibody responses, and show that a monocyte-related signature correlates with the neutralizing antibody response against the B.1.351 variant. Collectively, these data provide insights into the immune responses induced by mRNA vaccination and demonstrate its capacity to prime the innate immune system to mount a more potent response after booster immunization.Profiling the immune responses of 56 volunteers vaccinated with BNT162b2 reveals how this mRNA vaccine primes the innate immune system to mount a potent response to SARS-CoV-2 after booster immunization. [ABSTRACT FROM AUTHOR]

The development of a portfolio of COVID-19 vaccines to vaccinate the global population remains an urgent public health imperative1. Here we demonstrate the capacity of a subunit vaccine, comprising the SARS-CoV-2 spike protein receptor-binding domain displayed on an I53-50 protein nanoparticle scaffold (hereafter designated RBD–NP), to stimulate robust and durable neutralizing-antibody responses and protection against SARS-CoV-2 in rhesus macaques. We evaluated five adjuvants including Essai O/W 1849101, a squalene-in-water emulsion; AS03, an α-tocopherol-containing oil-in-water emulsion; AS37, a Toll-like receptor 7 (TLR7) agonist adsorbed to alum; CpG1018-alum, a TLR9 agonist formulated in alum; and alum. RBD–NP immunization with AS03, CpG1018-alum, AS37 or alum induced substantial neutralizing-antibody and CD4 T cell responses, and conferred protection against SARS-CoV-2 infection in the pharynges, nares and bronchoalveolar lavage. The neutralizing-antibody response to live virus was maintained up to 180 days after vaccination with RBD–NP in AS03 (RBD–NP-AS03), and correlated with protection from infection. RBD–NP immunization cross-neutralized the B.1.1.7 SARS-CoV-2 variant efficiently but showed a reduced response against the B.1.351 variant. RBD–NP-AS03 produced a 4.5-fold reduction in neutralization of B.1.351 whereas the group immunized with RBD–NP-AS37 produced a 16-fold reduction in neutralization of B.1.351, suggesting differences in the breadth of the neutralizing-antibody response induced by these adjuvants. Furthermore, RBD–NP-AS03 was as immunogenic as a prefusion-stabilized spike immunogen (HexaPro) with AS03 adjuvant. These data highlight the efficacy of the adjuvanted RBD–NP vaccine in promoting protective immunity against SARS-CoV-2 and have led to phase I/II clinical trials of this vaccine (NCT04742738 and NCT04750343).Trials in rhesus macaques show that a subunit vaccine against SARS-CoV-2, comprising the spike protein receptor-binding domain displayed on a nanoparticle protein scaffold, produces a robust protective response against the virus. [ABSTRACT FROM AUTHOR]

Many works have been conducted in the field of lithium-sulfur batteries, which have high specific capacity and energy density. Besides, the element sulfur is environmental friendly, low cost, and abundant. During the past decades, great efforts have been paid to improve the electrochemical performance of lithium-sulfur batteries. However, there is still a long way to achieve the wide application of lithium-sulfur batteries. The main reasons are the poor electronic conductivity and severe shuttle effect of the soluble polysulfide in the lithium-sulfur batteries. Therefore, it is the efficient method to design the sulfur host materials, which could improve the electronic conductivity and inhibit the shuttle effect in the lithium-sulfur batteries. Herein, carbon nanofibers were prepared and designed as sulfur hosts in lithium-sulfur batteries. Due to the presence of the carbon nanofibers, the as-prepared carbon nanofibers/S (CNFs/S) composites exhibited excellent electrochemical performances. [ABSTRACT FROM AUTHOR]

In this work, the adiabatic shear band of TA1 titanium alloy subjected to electromagnetic impact loading was investigated. The formation of adiabatic shear band and microstructure evolution within it were revealed by microstructure characterizations. Deformation results showed an adiabatic shear band with the width of 10 μm located in shear deformation zone, and most deformations mainly concentrated in the narrow band. The compressive instability and the hardness difference contributed to the formation of adiabatic shear band. Severe shear deformations led to high location density within the adiabatic shear band. A large amount of dislocations distributed in the form of dislocation cells and random dislocations. The rotational dynamic recrystallization mechanism caused that many dynamic recrystallization grains with the size of 100–200 nm were found inside the adiabatic shear band. Adiabatic temperature rise and distortion energies stored by high dislocation densities provided sub-grain rotations with the driving forces. [ABSTRACT FROM AUTHOR]

In this work, an electromagnetic-mechanical-thermal coupling numerical model was proposed and electromagnetic riveting (EMR) experiments were performed using Φ6 mm TA1 titanium alloy rivets. Experimental verification showed that the proposed model could be suitable for predicting the EMR process, and the corresponding relationships among magnetic pressures, deformations of rivet tails and discharge voltages were revealed. In addition, simulation results presented that most deformations occurred in the locally upsetting stage of rivet tail. The maximum temperature rise reached up to 426 °C within the shear deformation zone of rivet tail. The rivet tails with high speed deformations could bear 9.9 kN shear loads and 12.5 kN pull-out loads, respectively. The EMR joining structures with multi-layered sheets had very high interference-fit qualities, and the average relative interferences were 2.5–3.0% for as-received multi-layered structures. Consequently, the EMR process can be used for difficult-to-deformation material rivets under the high efficiency, high quality and ambient temperature. [ABSTRACT FROM AUTHOR]

Purpose: Systemic Inflammation Response Index (SIRI), based on peripheral neutrophil, monocyte, and lymphocyte counts, was recently developed and used as a marker to predict the survival of patients with malignant tumours. Cancer stem cells (CSCs) can contribute to gastric cancer progression and recurrence. It is not clear whether SIRI is associated with CSCs during gastric cancer development. Methods: The SIRI was developed in a training cohort of 455 gastric cancer patients undergoing curative resection between 2007 and 2009, and validated in a validation cohort of 327 patients from 2010 to 2011. CD44 + CSCs were measured on tumour sections by immunohistochemical analysis. Results: An optimal cut-off point for the SIRI of 0.82 divided the gastric cancer patients into a low SIRI group (SIRI < 0.82) and a high SIRI group (SIRI ≥ 0.82) in the training cohort. Compared with patients who had a SIRI < 0.82, patients who had a SIRI ≥ 0.82 had a shorter disease-free survival (DFS) (HR 2.529; 95% CI 1.922-3.326; p < 0.001) and shorter disease-special survival (DSS) (HR 2.692; 95% CI 2.022-3.585; p < 0.001) in the training cohort, comparable DFS and DSS findings were observed in the validation cohort, even for patients in pathological TNM stage of I subgroup. A SIRI ≥ 0.82 was significantly associated with older age, larger tumour, higher pathological TNM stage, lymphovascular invasion, and perineural invasion. Additionally, patients in the low SIRI group were prone to DFS and DSS benefits from postoperative adjuvant chemotherapy. Univariate and multivariate analyses revealed that SIRI was an independent predictor for DFS and DSS. Furthermore, gastric cancer patients with CD44 + CSCs scores had higher SIRI level (mean 1.198 vs. 0.835; p < 0.001). In patients with CD44 + CSCs, those with SIRI ≥ 0.82 had higher recurrence rates and shorter survival time than patients with SIRI < 0. 82. Conclusions: SIRI was a useful prognostic indicator of poor outcomes in patients with gastric cancer and is a promising tool for gastric cancer treatment strategy decisions. The dismal outcomes in patients with high SIRI might be related to CSCs. [ABSTRACT FROM AUTHOR]

Electromagnetic forming (EMF) and electrohydraulic forming (EHF) are typical high speed forming technologies characterized with improved formability of sheet metal, single-sided die, and high precision deformation of parts. In this work, the bulging experiments of aluminum alloy tubes by EMF and EHF were performed to investigate the attaching-die capability, wall thickness, working hardness, and residual plasticity of deformed tubes. The results showed that the bulged tube by EMF is of low attaching-die capability, remarkable rebound, serious thinning of wall thickness, and prone to rupture in the outer corner. However, the parts by EHF process are of high attaching-die capability, almost no rebound, relatively uniform thickness, and remarkable fillet filling in the inner corner. The load mechanism contributes to the different deformation results of both processes. With the almost equivalent deformation, the tensile deformation ability of EHF part is better than that of EMF one, and the discharge energy efficiency of the former is higher than that of the latter. [ABSTRACT FROM AUTHOR]

During the late Miocene (~5.5 Ma), a large-scale submarine slide with an area of approximately 18000 km and a maximum thickness of 930 m formed in the deep-water region of the Qiongdongnan Basin. The large-scale submarine slide has obvious features in seismic profile, with normal faults in the proximal region, escarpments at the lateral boundary, and a pronounced shear surface at the base. The internal seismic reflections are chaotic and enclosed by parallel and sub-parallel seismic events. The main direction of sediment transport was from south to north and the main sediment source was the southern region of the Qiongdongnan Basin, which is located in the east of the Indo-China Peninsula and the north of the Guangle uplift. In this region, late Miocene strike-slip reversal of the Red River Fault, uplift and increased erosion of the Indo-China Peninsula, and an abrupt rise in the rate of deposition in the western part of the South China Sea provided the basic conditions and triggering mechanism for the large-scale submarine slide. The discovery of the large-scale submarine slide provides sedimentological evidence for the tectonic event of late Miocene strike-slip reversal of the Red River Fault. It can also be inferred that the greatest tectonic activity during the process of the Red River Fault reversal occurred at ~5.5 Ma from the age of top surface of the submarine slide. [ABSTRACT FROM AUTHOR]

Magnetic pulse cladding (MPC), a new technology, is proposed in this study to fabricate often utilized bi-metal tubing in engineering applications with an outer tubular component consisting of structurally strong material and an inner tubular layer of corrosion-resistant material. The MPC process includes an innovative feature that allows the outer and inner tubes to electromagnetically bond together by a sequential expansion process to form a mechanical bond between the tubes at the interface. The MPC process was experimentally arranged to produce an Al/Fe bi-metal tube with an outer carbon steel tube and an internal aluminum tube. A mechanical test was then applied to characterize bonding strength of the Al/Fe bi-metal tube. Significant process parameters including discharging voltage, radial gap, and feeding length were identified based on bonding strength influence. Overall feasibility was demonstrated for the MPC process in electromagnetic expansion pattern in the production of bi-metal tubing. [ABSTRACT FROM AUTHOR]

Otubains are a recently identified family of deubiquitinating enzymes (DUBs). They are involved in diverse biological processes including protein degradation, signal transduction, and cell immune response. Several microsporidian genomes have been published in the last decade; however, little is known about the otubain-like protease in these widely-spread obligate intracellular parasites. Here, we characterized a 25 kDa otubain-like protease (NbOTU1) from the microsporidian Nosema bombycis, the pathogen causing pebrine disease in the economically important insect Bombyx mori. Sequence analysis showed that this protein contained a conserved catalytic triad of otubains composed of aspartate, cysteine, and histidine residues. The expression of Nbotu1 began on day 3 postinfection as determined by the RT-PCR method. Immunofluorescence analysis indicated that NbOTU1 is localized on the spore wall of N. bombycis. The subcellular localization of the NbOTU1 was further detected with immunoelectron microscopy, which showed that NbOTU1 is localized at the regions around endospore wall and plasma membrane. Deubiquitination analysis confirmed that the recombinant NbOTU1 possessed deubiquitination activity in vitro. Taken together, a novel microsporidian otubain-like protease NbOTU1 was partially characterized in N. bombycis, demonstrating its subcellular location and deubiquitination activity. This study provided a basic reference for further dissecting the function of otubains in microsporidia. [ABSTRACT FROM AUTHOR]

P-selectin glycoprotein ligand-1 (PSGL-1) is involved in the initial step of lymphocyte homing by interacting with P- or E-selectins expressed on activated endothelium cells. Besides, it also functions as a receptor to induce signals that increase integrin affinity to ligands and mediate cell adhesion to endothelium. Integrin is required for the second step of lymphocyte homing, whose activation has been reported tightly regulated by inside-out signals triggered by chemokines or the shear-stress generated during lymphocyte rolling on endothelium. However, the relationship between PSGL-1-triggered signals and integrin activation is not clear. In this study, we demonstrated that PSGL-1 ligation induces β1 integrin-mediated adhesion to fibronectin via regulation of both β1 subunit clustering and conformation changes. Phosphoinositide 3-kinase (PI3K) is required for PSGL-1-induced β1 integrin clustering which ultimately regulates β1 integrin-mediated Jurkat cell adhesion to fibronectin. However, PI3K is not involved in the conformation changes or increases in the total expression of β1 integrin. Taken together, we found a novel signal pathway, PSGL-1-PI3K-β1 integrin, demonstrating the cooperation between initial adhesion and subsequent arrest and stable adhesion. [ABSTRACT FROM AUTHOR]

We review and discuss some of the recent scientific findings made on magnetic data in the South China Sea (SCS). Magnetic anomalies bear extremely rich information on Mesozoic and Cenozoic tectonic evolution. 3D analytical signal amplitudes computed from magnetic anomalies reveal very precisely relict distributions of Mesozoic sedimentary sequences on the two conjugate continental margins, and they are also found very effective in depicting later-stage magmatism and tectonic transitions and zonation within the SCS oceanic crust. Through integrated analyses of magnetic, gravity and reflection seismic data, we define the continent-ocean boundary (COB) around the South China Sea continental margin, and find that the COB coincides very well with a transition zone from mostly positive to negative free-air gravity anomalies. This accurate outlining of the COB is critical for better tracing magnetic anomalies induced by the oceanic crust. The geometrically complex COB and inner magnetic zonation require the introduction of an episodic opening model, as well as a transform fault (here coined as Zhongnan Fault) between the East and Southwest Sub-basins, while within the East and Southwest Sub-basins, magnetic anomalies are rather continuous laterally, indicating nonexistence of large transform faults within these sub-basins. We enhance magnetic anomalies caused by the shallow basaltic layer via a band-pass filter, and recognize that the likely oldest magnetic anomaly near the northern continental margin is C12 according to the magnetic time scale CK95. Near the southern continental margin, magnetic anomalies are less recognizable and the anomaly C12 appears to be missing. These differences show an asymmetrical opening style with respect to the relict spreading center, and the northern part appears to have slightly faster spreading rates than to the south. The magnetic anomalies C8 (M1 and M2, ∼26 Ma) represent important magnetic boundaries within the oceanic basin, and are possibly related to changes in spreading rates and magmatic intensities. The magnetic evidence for a previously proposed ridge jump after the anomaly C7 is not clear. The age of the Southwest Sub-basin has yet to be further examined, most favorably with deep-tow magnetic surveys and ocean drilling. Our magnetic spectral study shows that the shallowest Curie points are located around the eastern part of the Southwestern Sub-basin, whereas within the East Sub-basin Curie depths are smaller to the north of the relict spreading center than to the south. This pattern of Curie depths is consistent to regional heat flow measurements and later-stage volcanic seamount distributions, and we therefore reason that Curie-depth variations are closely associated with later-stage magmatism, rather than with crustal ages. Although magnetic anomalies located around the northern continent-ocean transition zone (COT) are relatively quiet, this area is not a typical magnetic quiet zone since conceptually it differs markedly from an oceanic magnetic quiet zone. The relatively quiet magnetic anomalies are seemingly associated with a shallowing in Curie isotherm and thinning in magnetic layer, but our comprehensive observations suggest that the well-preserved thick Mesozoic sedimentary rocks are major causes for the magnetically quiet zone. The high similarities between various low-pass filtered marine and air-borne magnetic anomalies and satellite magnetic anomalies clearly confirm that deeper magnetic sources (in the lower crust and the uppermost mantle) have contributions to long-wavelength surface magnetic anomalies in the area, as already inferred from magnetically inversed Curie depths. The offshore south China magnetic anomaly (SCMA) becomes more prominent on low-pass filtered marine and air-borne magnetic anomalies and satellite magnetic anomalies, indicating very deeply-buried magnetic sources beneath it. [ABSTRACT FROM AUTHOR]

As a successively and locally plastic deformation process, ball spinning is applied to manufacturing thin-walled Nickel-Titanium shape memory alloy (NiTi SMA) tube at high temperature. NiTi SMA tube blank belongs to the as-cast state which consists of a lot of dendritic grains and a few equiaxed grains. The compression tests of NiTi SMA were carried out at various strain rates at high temperature in order to obtain the constitutive model of NiTi SMA. Because NiTi SMA is sensitive to the strain rates at high temperature, rigid-viscoplastic finite element method (FEM) is used to simulate ball spinning of thin-walled NiTi SMA tube in order to analyze the deformation behavior of ball spinning of NiTi SMA tube. Stress fields, strain fields as well as velocity fields is obtained by means of rigid-viscoplastic FEM, which lays the profound foundations for studying the metal flow rule in ball spinning and forming perfect spun NiTi SMA tube. [ABSTRACT FROM AUTHOR]

To establish the efficacy of electromagnetically assisted sheet metal stamping (EMAS), a series of combined hydraulic bulging and electromagnetic forming (EMF) experiments are presented to evaluate the biaxial quasi-static-dynamic formability of an aluminum alloy (AA5052-O) sheet material. Data on formability are plotted in principal strain space and show an enhanced biaxial formability beyond the corresponding experimental results from conventional forming limit diagram. The plastic strains produced by the combined process are a little larger than or at least similar with those obtained in the fully dynamic EMF process. In addition, the biaxial forming limits of aluminum sheets undergoing both very low and high quasi-static prestraining are almost similar in quasi-static-dynamic bulging process. Limit formability seems to depend largely on the high-velocity loading condition as dictated by EMF. It appears that in quasi-static-dynamic forming, quasi-static loading is not of primary importance to the material's formability. Based on these observations, one may be able to develop forming operations that take advantage of this formability improvement of quasi-static-dynamic deformation. Also, this could enable the use of a quasi-static preform fairly close to the quasi-static material limits for the design of an EMAS process. [ABSTRACT FROM AUTHOR]

The effects of temperature (0–500°C) on the compressive strength, hardness, average relative density, and microstructure of Ti6Al4V powder green compacts prepared by magnetic pulse compaction were investigated. The results show that with increasing heating temperature, the compressive strength first increases and then decreases with the maximum value of 976.74 MPa at 400°C. The average relative density and hardness constantly increase, and their values reach 96.11% and HRA 69.8 at 500°C, respectively. The increase of partial welding is found among the junctions of particles inside the compacts; there is no obvious grain growth inside the compacts within the temperature range. [ABSTRACT FROM AUTHOR]

Through reduction to the North Pole and upward continuation of the total field magnetic anomalies, we analyze magnetic patterns and spatial distributions of different tectonic blocks and crustal faults in eastern China and adjacent seas. Depths to the Curie isotherms are further estimated from radially averaged amplitude spectra of magnetic data reduced to the pole. Data reductions effectively enhance boundaries of regional tectonic belts, such as the Dabie ultra-high metamorphic belt, the Tanlu Fault, and the Diaoyudao Uplift. Curie depths are estimated at between 19.6 and 48.9 km, with a mean of 31.7 km. The Subei Basin and the south Yellow Sea Basin in the lower Yangtze block show relatively deep Curie isotherms, up to about 35 km in depth, whereas in the surrounding areas Curie depths are averaged at about 25 km. This implies that the lower Yangtze Block has experienced a unique tectonic evolution and/or has unique basement lithology and structures. From a regional perspective, sedimentary basins, such as the Subei Basin, the south Yellow Sea Basin, and the East China Sea Basin, normally show deeper Curie isotherms than surrounding uplifts such as the Diaoyudao Uplift and the Zhemin Uplifts. Curie isotherms also upwell significantly in volcanically active areas such as the Ryukyu Arc and the Cheju Island, confirming strong magmatic and geothermal activities at depth. [ABSTRACT FROM AUTHOR]

Sponsored by the Chinese National Fundamental Research and Development Program in 2001, Guangzhou Marine Geological Survey launched out a long geophysical survey from the northeastern part of the South China Sea (SCS), through the Luzon Arc, to the Huatung Basin and the Gagua Ridge. Based on high-resolution seismic data from this survey, combined with gravimetric and magnetic modeling, a systematic effort is made to the study of the regional geodynamics offshore southern Taiwan. By focusing particularly on precollisional tectonic interactions between adjacent geological units and their tectonic affiliations, this study can help reveal early arc-continent collisional processes that formed the Taiwan orogen. The construction of the Manila accretionary prism and its eastward progressive deformation indicate that the subduction of SCS have experienced multiple phases of increased activity. Active precollisional crustal shortening within the Northern Luzon Trough resulted in tilting of sedimentary layers at angles between 6° and 13°. But the shortening induced by tilting accounts for only a tiny part of regional total crustal compression. The eastern flank of the Luzon Arc appears to be more active than the rest, evidenced by active faulting and folding in the intra-arc basins on the eastern flank. Magnetic modeling/inversion shows that the Luzon Arc may have experienced multiple phases of magmatic activities, causing lateral magnetic inhomogeneity. Bouguer gravity anomalies and gravity modeling indicate that the Huatung Basin has anomalously higher crustal and upper mantle densities than those of SCS and the Luzon Arc. In addition, there is a large bathymetric difference between the Huatung Basin and the northeastern part of SCS basin. These observations argue against early hypothesis that the Huatung Basin and the northeastern part of SCS basin may once have belonged to one single oceanic crust, in part or in whole. The Gagua Ridge, as a sliver of uplifted oceanic crust, may be related to a transient northwestward subduction of the western Philippine plate. All evidences point to the argument that the region offshore southern Taiwan is experiencing multiple terrain amalgamation, which is a classical model for continental growth. [ABSTRACT FROM AUTHOR]

Francisella tularensis is a potential biowarfare/bioterrorism agent and zoonotic pathogen that causes tularemia; thus, surveillance of F. tularensis and first-level emergency response using point-of-care testing (POCT) are essential. The UPT-LF POCT assay was established to quantitatively detect F. tularensis within 15 min, and the sensitivity of the assay was 104 CFU · mL−1 (100 CFU/test). The linear quantitative range covered five orders of magnitude, and the coefficients of variation were less than 10%. Except Shigella dysenteriae, UPT-LF showed excellent specificity to four strains that are also potential biowarfare/bioterrorism agents and 13 food-borne pathogenic strains. Samples with pH 2-13, high ion strengths (≥2 mol · L−1 solution of KCl and NaCl), high viscosities (≤50 mg · mL−1 PEG20000 or ≥20% glycerol), and high concentrations of biomacromolecules (≥400 mg · mL−1 bovine serum albumin or ≥80 mg · mL−1 casein) showed little influence on the assay. For practical utilization, the tolerance limits for seven powders and eight viscera were determined, and operation errors of liquid measurement demonstrated a minor influence on the strip. Ftu-UPT-LF is a candidate POCT method because of its excellent sensitivity, specificity, and stability in complex samples, as well as low operation error. [ABSTRACT FROM AUTHOR]