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In key areas of ecological protection, it is significant to consider the similarity of pollution sources among heavy metals and the interaction between different sources, especially the ecological risk areas caused by heavy metal pollution. We collected 51 soil samples from five land use types with different soil depths in an industrial area on the Qinghai-Tibet Plateau. Two and three major heavy metal combination types of Cd Cu Cr Pb and Zn in different soil layers were identified using absolute principal component score-multiple linear regression models, and the potential pollution sources corresponding to the different types were quantified using Geo-Detector models. Industrial activities, especially metallurgy and mining, are the most likely potential sources of Cd Cu and Pb pollution, while the enrichment effects caused by rivers and roads are also evident in the study area. Heavy metal levels were generally higher in watered and urban lands and lower in grasslands. The downward migration of heavy metals in the study area was inferred from the similar trends of several indicators between soil layers A and B. The new model Nemerow Integrated Risk Index (NIRI) was used to analyse the integrated ecological risk across the study area and under different land use types by comparing with the pollution load index and Nemerow Integrated Pollution Index, and it was found that the risk level was lower in grassland and forest land than under other land use types, while it was higher in urban land and irrigated land. NIRI was able to highlight the impact of high Cd toxicity factors on the overall risk level, and is more accurate and flexible in identifying risk areas.

While the gig economy provides flexible jobs for millions of workers globally, a lack of organization identity and coworker bonds contributes to their low engagement and high attrition rates. To test the impact of virtual teams on worker productivity and retention, we conduct a field experiment with 27,790 drivers on a ride-sharing platform. We organize drivers into teams that are randomly assigned to receiving their team ranking, or individual ranking within their team, or individual performance information (control). We find that treated drivers work longer hours and generate significantly higher revenue. Furthermore, drivers in the team-ranking treatment continue to be more engaged 3 mo after the end of the experiment. A machine-learning analysis of 149 team contests in 86 cities suggests that social comparison, driver experience, and within-team similarity are the key predictors of the virtual team efficacy.

Predicting the failure time of unstable slopes is one of the most pivotal issues. In this paper, the inverse square root acceleration (INSRA) method was proposed to estimate the time-of-failure (TOF) of landslides. Four collapsed slopes were presented in the three open-pit mines, two of them were probed by ground-based radar, and two of them were obtained from previous scientific papers. The inverse velocity (INV) method and INSRA method were adopted to analyze these four landslides and one slope which had great deformation but did not reach failure. Compared with the traditional INV method, the INSRA method can promote the forecasting effectiveness and has the advantage of higher accuracy.

Libman-Sacks endocarditis, characterized by verrucous vegetations formation, is a typical cardiac manifestation of autoimmune diseases such as systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS). Although typically mild and asymptomatic, Libman-Sacks endocarditis can lead to serious complications, including thromboembolic events, superimposed bacterial endocarditis, and severe valvular regurgitation and/or stenosis, and valve surgery may be required. Here, we report a case of mitral valve repair for a large Libman-Sacks vegetation in a 29-year-old woman with a history of APS with cerebral infarction. Transesophageal echocardiography (TEE) demonstrated an isolated large mobile vegetation on the atrial side of posterior mitral valve leaflet, with severe mitral regurgitation. Next, we organized a multidisciplinary team meeting to better evaluate the case before performing the surgery. To prevent further thromboembolic events, and due to the insufficiency of the mitral valve, the patient was accepted for mitral valve surgery, and she was discharged uneventfully 10 days after successful surgery. She was managed with long-term anticoagulation medicine after surgery and followed up for 2 years with no complications. The present case showed mitral repair is feasible and effective in young female patients of child-bearing age, and the lesion only localized mitral valve abnormalities caused by Libman-Sacks endocarditis.

Tendinopathy is a common musculoskeletal disorder which results in chronic pain and reduced performance. The therapeutic effect of stem cell derived-small extracellular vesicles (sEVs) for tendinopathy has been validated in recent years. However, whether large extracellular vesicles (lEVs), another subset of extracellular vesicles, possesses the ability for the improvement of tendinopathy remains unknown. Here, we showed that lEVs secreted from iPSC-derived MSCs (iMSC-lEVs) significantly mitigated pain derived from tendinopathy in rats. Immunohistochemical analysis showed that iMSC-lEVs regulated the heterogeneity of infiltrated macrophages and several inflammatory cytokines in rat tendon tissue. Meanwhile

The hydrolysis of formaldehyde (HCHO) assisted by bimolecular acidic catalysts of H2SO4●●●H2O and (H2SO4)2 under different concentrations of H2SO4 and H2O were performed by quantum chemical calculations and the Master Equation method. The calculated results show that H2SO4●●●H2O and (H2SO4)2 catalyzed hydrolysis reaction of HCHO can occur through both one-step route and stepwise process. Effective rate coefficients (kt′) within the temperature range of 280-320 K show that H2SO4●●●H2O assisted reaction via stepwise route exerts the strongest catalytic role in increasing the rate of the hydrolysis of HCHO among all the hydrolysis reactions with H2SO4●●●H2O and (H2SO4)2 with its effective rate coefficient larger by at least 1 order of magnitude. As compared with the naked hydrolysis of HCHO, the favorable route of the hydrolysis of HCHO with H2SO4●●●H2O can reduce the energy barrier by 32.0 kcal·mol-1. Meanwhile, this reaction is also lower by another 0.8-17.6 kcal·mol-1 than that with H2SO4, HCOOH, HNO3, CH3COOH, H2O and (H2O)2. The calculated kt′ also reveals that the hydrolysis of HCHO with H2SO4●●●H2O ([H2SO4] =108 molecules∙cm-3 and [H2O] at 20%-100% RH) is more effective than that with H2O and (H2O)2 within 280-320 K, and can compete well with the hydrolysis of HCHO in the presence of HCOOH (2-10 ppbv), HNO3 (1011 molecules●cm-3), CH3COOH (1-5 ppbv) within 280-320 K. So, this work predicts that H2SO4●●●H2O can play a significant role in the hydrolysis of HCHO in the condition of wet areas with relatively high H2SO4-polluted.

Aim: This study aimed to explore the effect of small extracellular vesicles from induced pluripotent stem cell-derived mesenchymal stem cells (iMSC-sEVs) on acute pain and investigate the underlying mechanisms. Materials & methods: The pathology of tendons was accessed by hematoxylin and eosin staining, immunohistochemical and immunofluorescent staining. The pain degree was measured by pain-related behaviors. In vitro, we performed β-hexosaminidase release assay, RT-qPCR, toluidine blue staining, ELISA and RNA sequencing. Results: iMSC-sEVs effectively alleviated acute pain in tendinopathy as well as inhibiting activated mast cell infiltration and interactions with nerve fibers in vivo. In vitro, iMSC-sEVs reduced the degranulation of mast cells and the expression of proinflammatory cytokines and genes involved in the HIF-1 signaling pathway. Conclusion: This study demonstrated that iMSC-sEVs relieved tendinopathy-related pain through inhibiting mast cell activation via the HIF-1 signaling pathway.

Background: Acute pain is the primary symptom of tendinopathy, and mast cells activation is a nonnegligible cause. Currently, safe and effective treatment for acute pain in tendinopathy is still lacking. This study was aimed to explore the analgesic effect of iPSC-derived mesenchymal stem cell-derived small extracellular vesicles (iMSC-sEVs) on acute pain and further investigate the underlying mechanisms in tendinopathy. Methods: A rat tendinopathy model was established and then treated with iMSC-sEVs or PBS for 4 weeks. The pathology of tendinopathy was accessed by H&E staining and immunohistochemical analysis 2 and 4 weeks after treatment. Then we measured pain-related behaviors 4 weeks after treatment. Double immunofluorescent staining on tendon sections for tryptase and PGP9.5 was conducted to assess whether iMSC-sEVs inhibit mast cells activation in tendinopathy. To further investigate the potential mechanism, RBL-2H3 cells were stimulated with substance P to mimic tendinopathy condition in vitro. The effect of iMSC-sEVs on inhibiting mast cells activation was measured by b-Hexosaminidase release assay, RT-qPCR, Toluidine blue staining and ELISA. RNA-seq was performed to analyze the related global changes and discover the underlying mechanism. Results: iMSC-sEVs effectively reduced inflammation, thereby alleviating acute pain in tendinopathy as reflected by histological analysis and pain-related behaviors. Moreover, iMSC-sEVs inhibited activated mast cell infiltration and interactions with nerve fibers in tendinopathy. In vitro study showed that the expression of proinflammatory cytokines and the degranulation of mast cells induced by substance P were reduced upon iMSC-sEVs treatment. Transcriptome analysis revealed that iMSC-sEVs treatment down-regulated the expression of genes involved in the HIF-1 signaling pathway.Conclusion: Overall, this study demonstrated that iMSC-sEVs relieved tendinopathy-related pain through inhibiting mast cells activation partly via the HIF-1 signaling pathway. These findings provide a novel treatment strategy for pain derived from tendinopathy and unravel the molecular mechanism underlying the application of iMSC-sEVs on mast cells.

Zhaochen Zhu,1,2,* Renzhi Gao,1,2,* Teng Ye,1,2 Kai Feng,1,2 Juntao Zhang,2 Yu Chen,2 Zongping Xie,1 Yang Wang2 1Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, 200233, People’s Republic of China; 2Institute of Microsurgery on Extremities, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, 200233, People’s Republic of China*These authors contributed equally to this workCorrespondence: Zongping Xie, Department of Orthopaedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, 600# Yishan Road, Shanghai, 200233, People’s Republic of China Email x91034@qq.comBackground: Tendinopathy is a common cause of tendon pain. However, there is a lack of effective therapies for managing tendinopathy pain, despite the pain being the most common complaint of patients. This study aimed to evaluate the therapeutic effect of small extracellular vesicles released from induced pluripotent stem cell-derived mesenchymal stem cells (iMSC-sEVs) on tendinopathy pain and explore the underlying mechanisms.Methods: Rat tendinopathy model was established and underwent the injection of iMSC-sEVs to the quadriceps tendon one week after modeling. Pain-related behaviors were measured for the following four weeks. Tendon histology was assessed four weeks after the injection. To further investigate the potential mechanism, tenocytes were stimulated with IL-1β to mimic tendinopathy in vitro. The effect of iMSC-sEVs on tenocyte proliferation and the expression of proinflammatory cytokines were measured by CCK-8, RT-qPCR, and ELISA. RNA-seq was further performed to systematically analyze the related global changes and underlying mechanisms.Results: Local injection of iMSC-sEVs was effective in alleviating pain in the tendinopathy rats compared with the vehicle group. Tendon histology showed ameliorated tendinopathy characteristics. Upon iMSC-sEVs treatment, significantly increased tenocyte proliferation and less expression of proinflammatory cytokines were observed. Transcriptome analysis revealed that iMSC-sEVs treatment upregulated the expression of genes involved in cell proliferation and downregulated the expression of genes involved in inflammation and collagen degeneration.Conclusion: Collectively, this study demonstrated iMSC-sEVs protect tenocytes from inflammatory stimulation and promote cell proliferation as well as collagen synthesis, thereby relieving pain derived from tendinopathy. As a cell-free regenerative treatment, iMSC-sEVs might be a promising therapeutic candidate for tendinopathy.Keywords: tendinopathy, pain relief, extracellular vesicles, iPSC derived MSC

Our aim was to examine whether the influence of apolipoprotein E4 (APOE4) genotype on cognitive decline differs in male and female across the Alzheimer's disease (AD) continuum. Among individuals with normal cognition (NC; n = 415), mild cognitive impairment (MCI; n = 870), and AD (n = 334), we investigated the longitudinal associations of APOE4 genotype and sex with cognitive decline over 13 years. Our cognitive outcomes were Rey Auditory Verbal Learning Test (RAVLT) total learning score and delayed recall and Mini-Mental State Examination (MMSE) score. There were significant effects of the APOE4×sex interaction on change in verbal memory in the MCI group, but not the NC or AD group. Specifically, among individuals with MCI, female APOE4 carriers had a steeper decline in RAVLT total learning score, but not delayed recall or MMSE score compared to all other groups (APOE4 + /Male, APOE4-/Female, APOE4-/Male). In conclusion, female APOE4 carriers have faster rates of memory decline than their male counterparts among MCI individuals.

Background: Left ventricular noncompaction with multiple left ventricular thrombi can be revealed by echocardiography, and early diagnosis seems to be imperative to prevent significant embolic events. Case Report: A 57-year-old woman presented with symptoms of heart failure. Two-dimensional transthoracic echocardiogram demonstrated a dilated and diffusely hypokinetic left ventricle with severe impaired left ventricular systolic function. Moreover, a markedly thickened endocardium at the left ventricular apex and middle segment with numerous, excessively prominent trabeculations and deep intertrabecular recesses were present. During systole, the ratio of the noncompacted to compacted myocardial layers at the site of the maximal wall thickness was above two, a characteristic finding in left ventricular non-compaction. Multiple mobile, homogeneous, echodense thrombi were identified in the left ventricle, with the largest one in the apical noncompacted segment (dimensions, 32 × 14 mm). Cardiac magnetic resonance imaging confirmed the diagnosis of noncompacted myocardium with the presence of multiple thrombi. After anticoagulant therapy, her symptoms improved and thrombi dissolved. Unexpectedly, she re-admitted to the cardiovascular unit with progressive dyspnea. Transthoracic echocardiogram showed new large right atrial thrombi, with the largest one was 43 × 38 mm compared to the echocardiogram done 11 months ago. The patient was anticoagulated with continuous heparin infusion for several days followed by oral Apixaban. After 4 weeks, the floating thrombi completely disappeared. After a 26-month follow-up, the patient’s condition was stable without embolic complications. Conclusion: Echocardiography was the cornerstone of diagnostic methods for early detecting left ventricular thrombi to eventually prevent embolic events.

ObjectiveThere is growing evidence that testosterone may be implicated in the pathogenesis of Alzheimer’s disease (AD). We aimed to examine the relationship between plasma total testosterone levels and change in brain glucose metabolism over time among non-demented older people.MethodsThe association of plasma total testosterone levels with change in brain glucose metabolism among non-demented older people was investigated cross-sectionally and longitudinally. Given a significant difference in levels of plasma total testosterone between gender, we performed our analysis in a sex-stratified way. At baseline, 228 non-demented older people were included: 152 males and 76 females.ResultsIn the cross-sectional analysis, no significant relationship between plasma total testosterone levels and brain glucose metabolism was found in males or females. In the longitudinal analysis, we found a significant association of plasma total testosterone levels with change in brain glucose metabolism over time in males, but not in females. More specifically, in males, higher levels of total testosterone in plasma at baseline were associated with slower decline in brain glucose metabolism.ConclusionWe found that higher levels of total testosterone in plasma at baseline were associated with slower decline in brain glucose metabolism in males without dementia, indicating that testosterone may have beneficial effects on brain function.

Objective Developmental dysplasia of the hip (DDH) is the most common skeletal development in children and could result in secondary osteoarthritis. This study aims to clarify the alternations of subchondral trabecular bone remodeling and microstructural properties during the development of DDH, and the potential influence of these alternations on the overlying cartilage degeneration and DDH progression. Design Traditional straight-leg swaddling method was adopted to establish DDH model in newborn Sprague Dawley rats. Hip joint specimens from normal or DDH rats were used. Typical features of DDH in radiological examination were observed by x-ray analysis. Micro–computed tomography analysis was applied to evaluate the microstructural properties of subchondral bone at postnatal weeks 2, 4, and 6. Histological and immunohistochemical analyses were adopted to appraise subchondral bone remodeling activity and cartilage degeneration. The associations among subchondral bone, articular cartilage, and DDH severity were analyzed via multiple linear regression analysis. Results Compared with control group, the subchondral bone in DDH group displayed a gradual trend of deteriorated microstructure and worsening biomechanical properties along with aberrant bone remodeling, which might be responsible for the inhibition of stress transmission from the articular cartilage to the subchondral bone and thus leading to the cartilage degeneration and accelerated DDH progression. Conclusions Our findings indicate that alternations of subchondral trabecular bone in a time-dependent manner could contribute to the DDH progression and the amelioration on subchondral bone might be a favorable therapeutic candidate for DDH.

Conventional histological analysis and cell culture systems are insufficient to simulate in vivo physiological and pathological dynamics completely. Multiphoton microscopy (MPM) has become one of the most popular imaging modalities for biomedical study at cellular levels in vivo, advantages include high resolution, deep tissue penetration and minimal phototoxicity. We have designed an MPM imaging platform with a customized mouse eye holder and a stereotaxic stage for imaging ocular surface in vivo. Dual fluorescent protein reporter mouse enables visualization of cell nuclei, cell membranes, nerve fibers, and capillaries within the ocular surface. In addition to multiphoton fluorescence signals, acquiring second harmonic generation (SHG) simultaneously allows for the characterization of collagenous stromal architecture. This platform can be employed for intravital imaging with accurate positioning across the entire ocular surface, including cornea and conjunctiva.

The heme oxygenase (HO) system is an important regulatory arm of the intrinsic cytoprotective and anti-inflammatory system. HO-2 plays an important role in regulating inflammation following injury. The aim of this study was to evaluate the effect of HO-2 overexpression on inflammatory responses. A skin transplantation model, involving the application of skin grafts from wild-type or HO-2 overexpressing mice to BALB/c mice, was used for investigation. HO-2 overexpression suppressed the production of pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6) in macrophages compared to that in macrophages obtained from control mice. HO-2 overexpression also significantly prolonged the survival of allografted skin. Our findings suggest that HO-2 attenuates inflammatory responses and effectively prolongs skin graft survival.

In typical application-like conditions, the inhomogeneous distribution and anisotropy of critical current density must be considered simultaneously in transport AC loss calculation. In this paper, we derive the analytical formulas of transport AC losses for high-temperature superconductors (HTSs) with linear and quadratic distribution of critical current density under applied DC magnetic field. The influence of the inhomogeneous distribution and anisotropy of critical current density has been analyzed. The results show that the impact of the distribution form on transport AC loss is more obvious under applied DC magnetic field. And the influence of applied DC magnetic field will increase as the distribution form becomes steeper.

This study systematically investigated the low cycle fatigue deformation of a high Nb-containing TiAl alloy with a nominal chemical composition of Ti-45Al-8.5Nb-0.2W-0.2B-0.02Y at 850 °C by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and synchrotron-based high-energy X-ray diffraction (HE-XRD) techniques. Cyclic stress-strain (CSS) behavior, lattice strain, and peak broadening of {100}α2, {201}γ, and {202}ωo planes, phase transformations, and crack propagation behavior were obtained for samples with three total strain amplitudes: Δet/2 = ±0.25%, Δet/2 = ±0.28%, and Δet/2 = ±0.30%. At early deformation stages, α2lamellae transformed into ωo phase with a distinct orientation relationship, and a certain orientation relationship (OR) between them was observed after the following cyclic deformation. Furthermore, γ particles precipitated within the single ωo area. In addition, according to the peak intensity and peak broadening results, the ωo → B2 phase transformation occurred, leading to the appearance of single B2-phase areas. The lattice strains in the ωo phase were always in tension during the cyclic deformation and large differences of the lattice strains were found in the γ phase and α2 phase, not only the values but also the directions, which resulted in crack nucleated at and propagated along the α2/γ lamellar interface. This study provides a better understanding of the low cycle fatigue deformation of TiAl alloys.

Creep rupture tests of the as-forged Ti-45Al-8.5Nb-(W,B,Y) alloy with a duplex microstructure were carried out at 750–850 °C and 130–300 MPa. An investigation was performed to study the effects of temperature and stress on the microstructure and texture evolution, as well as on the creep properties of the forged high Nb-containing TiAl alloy with a duplex microstructure. The results show that the stress exponent n = 2.8–3.3, and the creep activation energy values are in the range of 300–400 kJ/mol. After creep, a regular arrangement of ωo precipitations was observed in the βo region. The un-transformed βo phase, which remained in the ωo interval, was examined using high resolution transmission electron microscope (HRTEM). It is shown that the growth of ωo precipitations and the morphology of residual βo phases are related to the creep temperature and stress. Certain βo stabilizer elements, such as Nb, segregate into α2 plates and cause ωo precipitation during dissolution of α2 plates at high temperature. The interfacial structure between the ωo and α2 phases was studied in detail using HRTEM. Meanwhile, texture evolution and dynamic recrystallization of the γ phase were studied using electron backscatter diffraction (EBSD). Observations on the deformation structure also demonstrate that ωo precipitation acts as an obstacle inhibiting crack propagation and growth of the γ phase. The corresponding formation mechanism and possible effects on creep are discussed.

This paper mainly carries out researches on the small part samples of the spindles. Through the Weibull distribution and least squares,the mathematical analysis has made on the lifetime of ...

Phase equilibria in the Ti-Al-Nb ternary system at 1400 °C was established, using scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and electron probe micro-analysis (EPMA). No ternary compound was observed in this work. Compared with the calculated results, the α + β + γ three-phase region moves to higher Nb and Al contents and the σ + β + γ three-phase region moves to a lower Ti content in our experimental results. The tie-triangle of σ + δ + β moves to lower Ti and higher Nb contents. As a result, the homogeneity range of single α phase hugely expands to higher Nb and Al contents and the homogeneity range of single β phase region hugely expands to a higher Al content. The phase regions are also different with the previous reported experimental results.

Ordered omega (ω o ) phases are considered to be equilibrium phases in high Nb-TiAl alloys at intermediate temperatures. However, most studies have focused on the evolution behaviors of these phases during annealing, while the precipitation behavior has not been systematically studied. In the present work, the precipitation behavior of the ω o phase (B8 2 structure) in the Ti-45Al-8.5Nb-0.2W-0.2B-0.02Y (at.%) alloy during annealing at 850 °C was investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After annealing at 1150 °C for 2 h followed by water quenching, the ω o phase in the as-cast alloy transformed to the β o phase. At the initial stage of annealing processing at 850 °C, the ω o phase re-precipitated at the γ/β o boundaries and the size of the ω o phase increased with the annealing time. Moreover, the γ plates precipitated within the β o phase at this temperature became coarser and tended to globalize during annealing. In addition, the α 2 and D8 8 -ω phases were also observed at the γ/β o boundaries. Energy dispersive X-ray spectroscopy (EDS) and Scanning transmission electron microscopy (STEM) analysis showed that the D8 8 -ω phase is rich in W and Nb elements. The corresponding mechanisms of the transformation mentioned above were discussed.

Objective: To investigate whether APOE ε4 affects the association of verbal memory with neurodegeneration presented by the hippocampal volume/intracranial volume ratio (HpVR). Methods: The study sample included 371 individuals with normal cognition (NC), 725 subjects with amnestic mild cognitive impairment (aMCI), and 251 patients with mild Alzheimer's disease (AD) from the Alzheimer's Disease Neuroimaging Initiative (ADNI) who underwent the rey auditory verbal learning test (RAVLT). Multiple linear regression models were conducted to assess the effect of the APOE ε4∗HpVR interaction on RAVLT in all subjects and in each diagnostic group adjusting for age, gender and educational attainment, and global cognition. Results: In all subjects, there was no significant APOE ε4 × HpVR interaction for immediate recall or delayed recall (p > 0.05). However, in aMCI subjects, there was a significant APOE ε4 × HpVR interaction for delayed recall (p = 0.008), but not immediate recall (p = 0.15). More specifically, the detrimental effect of APOE ε4 on delayed recall altered by HpVR such that this effect was most evident among subjects with small to moderate HpVR, but this disadvantage was absent or even reversed among subjects with larger HpVR. No significant interaction was observed in the NC or AD group. Conclusion: These findings highlight a potential role of APOE ε4 status in affecting the association of hippocampus size with delayed recall memory in the early stage of AD.

The large scale ingot of Ti-45Al-8.5 Nb-(W, B, Y) alloy, which was manufactured by plasma arc cold hearth melting process, was successfully forged by a two-step canned forging process with a total deformation of 85%. The pancake is crack-free with smooth surface and presents recrystallized duplex microstructure. Additionally, the fraction of β/B2 phase in the as-forged microstructure has dropped. The high angle grain boundaries are dominant among recrystallized grains. After the heat treatments at different temperatures, the fine duplex, nearly lamellar and fully lamellar microstructures can be obtained respectively. Compared with the as-cast condition at room temperature, the ultimate tensile strength increases from 633 MPa to 897 MPa and the elongation improves from 0.23% to 2.2%. The strengths of as-forged TiAl alloy are relatively high at high temperatures. Moreover, superplastic behavior appears above 900 °C.

The microstructure and orientation relationship (OR) of the α2 and ωo phases in the Ti–34Al–13Nb (at. %) alloy were investigated. The α2 segments nucleated at the ωo boundaries after aging at 900 °C for 2 h. The ORs between the two phases were studied by selected area diffraction patterns using a transmission electron microscope and interpreted by the superimposed stereographic projections. Two ORs were defined as follows: $$ \left[ {1\bar{2}10} \right]\upalpha_{2} //\left[ {000\bar{1}} \right]\upomega_{o} $$ ; $$ (0002)\upalpha_{2} //\left[ {\bar{1}2\bar{1}0} \right]\upomega_{o} $$ and $$ \left[ {\bar{1}010} \right]\upalpha_{2} //\left[ {2\bar{4}2\bar{3}} \right]\upomega_{o} $$ ; $$ \left( {0002} \right)\upalpha_{2} //\left( {01\overline{12} } \right)\upomega_{o} $$ . Two α2 laths with parallel $$ \left\langle {\bar{1}102} \right\rangle $$ directions were observed in this alloy, which were explained by the different α2 variants nucleated at the ωo boundaries according to ORI and ORII.

Various behaviors of cancer cells are strongly influenced by their interaction with extracellular matrices (ECM). We investigate how this interaction may be influenced if the cancer cells’ ability of secreting matrix metalloproteinases (MMPs) to degrade ECM is inhibited by adding the MMP inhibitor. We use MDA-MB-231-GFP cells as model cells and use matrigel to mimic ECM. It is found that the added MMP inhibitor significantly reduces the migration speed of cancer cells covered by matrigel but has little influence on the migration persistence and shape factor of the cells and that with the MMP inhibitor added the presence of matrigel on the top has no influence on the migration speed of the cells but increases the cells’ shape factor and migration persistence.

As lower power requirements become more important and processes become more complex [1], the circuit is more and more affected by the process variation. The purpose of this paper is to research the optimization of low power circuits with high yield. We optimize a standard bandgap topology in 55 nm process technology in order to provide stable output voltage with minimal sensitivity to temperature, process variation and mismatch as the bandgap works in near-threshold field. Firstly, the priority of the circuit performance is determined. Then, the sensitivity of the performance to the device is analyzed. Lastly, the circuit parameters are adjusted by comprehensive consideration. After optimization, the average power of bandgap is only 300nA, with lower power requirements and higher yield. These findings are confirmed through Monte Carlo simulation and measured circuit data.

Individual panic behavior during an emergency is contagious. It often leads to collective panic behavior, which can be disruptive and even disastrous if handled incorrectly. In this paper, a novel kinetic model is developed to describe the dynamics of panic spreading in a real emergency. The global dynamics of the proposed model are analyzed by using the method of Lyapunov function and the Poincare–Bendixson property, and the obtained theoretical results are numerically validated. The Runge–Kutta method is used for numerical simulations, and these simulations are used to investigate the impact of corresponding management strategies on the containment of individual panic behavior. Meanwhile, the implications of these simulation results are discussed with the “2011 Xiangshui chemical explosion rumor” event. Finally, some recommendations for emergency management agencies are put forward by us to reduce individual panic behavior.

We compared the data reliability on a subjective task from two platforms: Amazon's Mechanical Turk (MTurk) and LabintheWild. MTurk incentivizes participants with financial compensation while LabintheWild provides participants with personalized feedback. LabintheWild was found to produce higher data reliability than MTurk. Our findings suggested that online experiment platforms providing feedback in exchange for study participation could produce more reliable data in subjective preference tasks than those offering financial compensation.

One particular problem CSCW and HCI scholars have sought to address through the design of collaborative systems is the issues associated with diversity and creativity. Diversity can promote creativity by exposing individuals to different perspectives and at the same time make it difficult for teams to leverage their differences to be more creative. This paper asserts that through the promotion of cooperation, collectivism will help ideation team members overcome the challenges associated with diversity and promote creativity. To examine this assertion, we conducted an experimental study involving 107 individuals in 33 idea-generation teams. Collectivism was promoted through priming. The results confirm our assertion: collectivism created conditions that facilitated creativity when teams were high in perceived diversity. Collectivism also facilitated more satisfaction among teammates by offsetting negative perceptions of diversity. These results offer new insights on collectivism, perceived diversity and creativity.

Hypodermin A (HA), a serine protease secreted by first-instar larvae of Hypoderma lineatum (Diptera: Oestridae) is associated with inflammatory and the specific immune responses in cattle hosts. In the present study, the cDNA sequence of HA was synthesized, and found to have fifteen amino acids which differed from the sequence available in GenBank. We then examined the association between recombinant HA and guinea-pig complement component 3 (C3) through a co-immunoprecipitation assay. Cos7 cells stably expressing HA were generated, and were found to be more resistant to lysis by guinea-pig C3 than the controls. HA was also able to degrade the C6 and C5b-9 of guinea-pig C3. The presumed DNA binding site of HA with guinea-pig C3 was detected by an electrophoretic mobility shift assay (EMSA). In contrast, after stable transfection, mHA was unable to reduce the amount of C3 or to inhibit its cytotoxicity, while HA could degrade guinea-pig C3 and inhibit the complement pathway. The findings suggest that recombinant HA could serve as an immunosuppressive agent against organ rejection after xenotransplantation.

The interaction between extracellular matrices and cancer cells plays an important role in regulating cancer cell behaviors. In this article, we use matrigel to mimic extracellular matrices and investigate experimentally how matrigel influences the shape and dynamics of breast cancer cells (MDA-MB-231-GFP cells). We find that matrigel facilitates cancer cells’ migration and shape deformation. The influences of the matrigel concentration are also reported.