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We prove a logarithmic improvement of the Caffarelli-Kohn-Nirenberg partial regularity theorem for the Navier-Stokes equations. The key idea is to find a quantitative counterpart for the absolute continuity of the dissipation energy using a pigeonholing argument. Based on the same method, for any suitable weak solution, we show the existence of intervals of regularity in one spatial direction with length depending exponentially on the natural local energies. Then, we give two applications of the latter result in the axially symmetric case. The first one is a local regularity criterion for suitable weak solutions with small swirl. The second one is a slightly improved one-point CKN criterion which implies all known (slightly supercritical) Type I regularity results in the literature. [ABSTRACT FROM AUTHOR]

In the short article we study the ideal incompressible magnetohydrodynamic equations in three dimensions in which the Faraday law is inviscid. We prove the global well-posedness of classical solutions for a family of special axisymmetric initial data whose swirl components of the velocity field and magnetic vorticity field are trivial. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with the 1-D compressible Euler–Poisson equations with moving physical vacuum boundary condition. It is usually used to describe the motion of a self-gravitating inviscid gaseous star. The local well-posedness of classical solutions is established in the case of the adiabatic index . [Copyright &y& Elsevier]

Abstract: Let be a solution to the three-dimensional incompressible axially-symmetric Navier–Stokes equations. Denote by the radial-axial vector field. Under a general scaling invariant condition on b, we prove that the quantity is Hölder continuous at , . As an application, we prove that the ancient weak solutions of axi-symmetric Navier–Stokes equations must be zero (which was raised by Koch, Nadirashvili, Seregin and Sverak (2009) in and Seregin and Sverak (2009) in as a conjecture) under the condition that . As another application, we prove that if , then v is regular. [Copyright &y& Elsevier]

Abstract: We provide a new proof for the global well-posedness of systems coupling fluids and polymers in two space dimensions. Compared to the well-known existing method based on the losing a priori estimates, our method is more direct and much simpler. The co-rotational FENE dumbbell model and the coupling Smoluchowski and Navier–Stokes equations are studied as examples to illustrate our main ideas. [Copyright &y& Elsevier]

Abstract: We provide a new method to prove and improve the Chemin–Masmoudi criterion for viscoelastic systems of Oldroyd type in [J.Y. Chemin, N. Masmoudi, About lifespan of regular solutions of equations related to viscoelastic fluids, SIAM J. Math. Anal. 33 (1) (2001) 84–112] in two space dimensions. Our method is much easier than the one based on the well-known losing a priori estimate and is expected to be easily adopted to other problems involving the losing a priori estimate. [Copyright &y& Elsevier]

Abstract: We study the domain of existence of a solution to a Riemann problem for the pressure gradient equation in two space dimensions. The Riemann problem is the expansion of a quadrant of gas of constant state into the other three vacuum quadrants. The global existence of a smooth solution was established in Dai and Zhang [Z. Dai, T. Zhang, Existence of a global smooth solution for a degenerate Goursat problem of gas dynamics, Arch. Ration. Mech. Anal. 155 (2000) 277–298] up to the free boundary of vacuum. We prove that the vacuum boundary is the coordinate axes. [Copyright &y& Elsevier]

Many endocrine disruptors may interfere with sperm motility, hyperactivation, and capacitation, thereby leading to male infertility. In the current study, we screened 14 endocrine disruptors, including plant ingredients, cigarette ingredients, minerals, insecticides and fungicides, plastics, and plasticizers, to inhibit human sperm motility and forward motility. Only ziram, a dithiocarbamate fungicide, can effectively inhibit sperm motility, forward motility, hyperactivation, capacitation, and spontaneous acrosome reaction of normal human spermatozoa. Its half maximum inhibitory concentration (IC 50) values were less than 4 μM. Ziram also inhibited sperm motility and forward motility of asthenozoospermia spermatozoa and IC 50 values were about 6–8 μM. In addition, ziram inhibited normal sperm motility, calcium influx, reactive oxygen species, and mitochondrial membrane potential at 2.5 and/or 5 μM, with IC 50 values ​​exceeding 100 μM, although it did not affect sperm DNA fragmentation up to 5 μM. Ziram-mediated inhibition of sperm motility and forward motility was irreversible. Forskolin, 8Br-cAMP, pentoxifylline, progesterone, vitamin E, and A23187 cannot prevent ziram-mediated inhibition of sperm motility and forward motility. Further studies have shown that ziram inhibited the level of tyrosine protein kinase with an IC 50 value of about 10 μM, without affecting p21-activated kinase 4, and it caused damage to the mitochondrial structure of normal spermatozoa at 2.5 and 5 μM. In conclusion, ziram irreversibly inhibits human sperm motility, forward motility, and capacitation by reducing the level of tyrosine protein kinase and damaging the ultrastructure of mitochondria. Ziram inhibits tyrosine protein kinase, which results in the inhibition of protein tyrosine phosphorylation, thereby inhibiting sperm motility, positive motility, capacitation, and the acrosome reaction. [Display omitted] • Ziram inhibits human sperm motility, forward motility, capacitation, the acrosome reaction. • Ziram inhibits human sperm calcium influx, reactive oxygen species, and mitochondrial membrane potential. • The inhibition of ziram on human sperm activity is irreversible. • Ziram inhibits human sperm tyrosine protein kinase. [ABSTRACT FROM AUTHOR]

Effective multi-object tracking (MOT) methods have been developed in recent years for a wide range of applications including visual surveillance and behavior understanding. Existing performance evaluations of MOT methods usually separate the tracking step from the detection step by using one single predefined setting of object detection for comparisons. In this work, we propose a new University at Albany DEtection and TRACking (UA-DETRAC) dataset for comprehensive performance evaluation of MOT systems especially on detectors. The UA-DETRAC benchmark dataset consists of 100 challenging videos captured from real-world traffic scenes (over 140,000 frames with rich annotations, including illumination, vehicle type, occlusion, truncation ratio, and vehicle bounding boxes) for multi-object detection and tracking. We evaluate complete MOT systems constructed from combinations of state-of-the-art object detection and tracking methods. Our analysis shows the complex effects of detection accuracy on MOT system performance. Based on these observations, we propose effective and informative evaluation metrics for MOT systems that consider the effect of object detection for comprehensive performance analysis. • New large scale dataset for both detection and multi-object tracking evaluation. • New protocol and evaluation metrics for multi-object tracking. • Comprehensive evaluation of complete multi-object tracking systems. [ABSTRACT FROM AUTHOR]

This study estimates the causal effects of traffic congestion on air quality in local areas within a city, highlighting the spatial and temporal variation in local traffic, local air pollution, and health risks to residents due to local pollutant exposure. We employ a large-scale taxi driving trajectory data to construct measures of traffic congestion in local areas surrounding air quality monitoring stations in Beijing, on an hourly basis. The station-by-hour panel data enables the estimation of both contemporaneous and lagged marginal effects of local traffic on local air pollution. We find that local traffic congestion increases concentrations of NO 2 and CO contemporaneously, but concentrations of PM 2.5 and PM 10 in a 2-h lagged manner. The magnitude and significance of the estimates vary with local traffic and pollution conditions, implying heterogeneous marginal effects on local air pollution of local traffic across locations, hours of the day, months and seasons. These results stress the importance of designing traffic policies that are both spatially and temporally fine-grained to attain efficiency and equity. [ABSTRACT FROM AUTHOR]

Abstract: α-Thalassemia is an inherited autosomal recessive disorder. It is one of the most common monogenic abnormalities known in the world and is prevalent in tropical and subtropical regions. α-Thalassemia is more frequently caused by deletional type than non-deletional type. Recently, we identified a novel large deletional type of α-thalassemia named --FZ/αα from a family in South China. Multiplex ligation-dependent probe amplification was used for diagnosing the carrier and prenatal diagnosing for a fetus. Real-time PCR was employed for characterizing the deletion breakpoints and the deletional segment was determined as 300kb in length extending from the telomere to AXIN1 gene on the short arm of chromosome 16. The carriers in the family members were detected by real-time PCR using designed primers. [Copyright &y& Elsevier]

Stem cells are specialized cells that can renew themselves through cell division and can differentiate into multi-lineage cells. Mesenchymal stem cells are adult stem cells that exist in animal and human tissues. Mesenchymal stem cells have the ability to differentiate into mesodermal lineages, such as Leydig cells, adipocytes, osteocytes, and chondrocytes. Mesenchymal stem cells express cell surface markers, such as cluster of differentiation (CD) 29, CD44, CD73, CD90, CD105, and lack the expression of CD14, CD34, CD45 and HLA (human leukocyte antigen)-DR. Stem Leydig cells are one kind of mesenchymal stem cells, which are present in the interstitial compartment of testis. Stem Leydig cells are multipotent and can differentiate into Leydig cells, adipocytes, osteocytes, and chondrocytes. Stem Leydig cells have been isolated from rodent and human testes. Stem Leydig cells may have potential therapeutic values in several clinical applications, such as the treatment of male hypogonadism and infertility. In this review, we focus on the latest research on stem Leydig cells of both rodents and human, the expression of cell surface markers, culture, differentiation potential, and their applications. [Display omitted] • Leydig cells develop from perivascular and peritubular stem Leydig cells. • Stem Leydig cells have some common biomarkers such as nestin. • When stem Leydig cells commit into the Leydig cell lineage with the expression of steroidogenic enzymes. • Some factors secreted by Sertoli cells are critical for stem Leydig cell differentiation such as desert hedgehog. • Some growth factors stimulate stem Leydig cell proliferation such as platelet-derived growth factor. [ABSTRACT FROM AUTHOR]

Angiotensin II receptor blocker has exhibited their renal protective benefits in diabetic nephropathy. This meta-analysis aimed to evaluate the effects of adding atorvastatin to irbesartan in early diabetic nephropathy. A systematic literature search was performed in PubMed, Embase, Cochrane Library, CNKI, VIP, and Wanfang database until March 25, 2019. Randomized controlled trials evaluating the effects of adding atorvastatin to irbesartan in early diabetic nephropathy were eligible. Primary endpoint was urinary albumin excretion rate, serum creatinine, and blood urea nitrogen. Serum level of total cholesterol, triglyceride, fasting blood glucose, interleukin-6,and C-reactive protein (CRP) as well as blood pressure were secondary endpoints. Seventeen trials involving 1,390 patients were identified. Compared with irbesartan alone, co-administration of atorvastatin and irbesartan significantly reduced urinary albumin excretion rate (weighted mean differences [WMD] -21.22 μg/min; 95% confidence interval [CI] -26.95 to -15.50), serum creatinine (WMD -6.46 μmol/L; 95%CI -8.52 to 4.39),BUN (WMD -0.46 mmol/L; 95%CI -0.64 to -0.27), total cholesterol (WMD -1.79 mmol/L; 95%CI -2.34 to -1.23), triglyceride (WMD -0.93 mmol/L; 95%CI -1.20 to -0.67),and systolic blood pressure (WMD -2.27 mmHg; 95%CI -4.01 to -0.53), CRP (standard mean difference [SMD] 1.57; 95%CI -2.24 to -0.9), and Interleukin-6 (SMD 1.53; 95%CI -2.29 to -0.78). However, there was a significantly increased risk of nausea/vomiting (risk ratio 3.15; 95% CI 1.18–8.38) on the co-administration group. In conclusion, adding atorvastatin to irbesartan achieves additional renal protective benefits in early diabetic nephropathy patients. However, these findings should be interpreted with caution due to suboptimal methodological quality of the analyzed trials. [ABSTRACT FROM AUTHOR]

In this article, we performed the stereo-photogrammetric processing on over 5200 Rosetta/OSIRIS-NAC images to derive a global high-resolution 3D model of the bilobate comet 67P/Churyumov-Gerasimenko, which is visually richer and more convincing than the existing models (i.e., SPG-SHAP4S, SPC-SHAP5 and SPG-SHAP7). This shape model was used to generate new measurements of the volume (18.62 ± 0.02 km3), the mean density (536.1 ± 0.7 kg/m3), and the surface area (54.0 ± 0.1 km2) of the 67P/C-G comet. Moreover, we also analyzed the reasons for the differences between the three models, namely the coverage of the image set and shadows. • High-resolution shape modeling of 67PC-G's nucleus using over 5200 images. • Better image matching on the surface of 67P/C-G with SuperPoint+SuperGlue. • This shape model is more detailed for the shaded areas. [ABSTRACT FROM AUTHOR]

Promoting angiogenesis by targeting various angiogenic regulators has emerged as a new treatment strategy for myocardial ischemia (MI). MicroRNA-126 (miR-126) has been identified as the main regulator of compensatory angiogenesis; however, its role in MI is unclear. A rat MI model and an EA. hy926 endothelial cell hypoxia model were constructed and it was found that miR-126 was highly expressed in both models. The knockdown of HIF-1α expression in EA. hy926 cells in turn downregulated VEGF and CD34 expression and consequently inhibited angiogenesis. MiR-126 inhibitor inhibited EA. hy926 cell migration and tube formation as well as downregulated VEGF and CD34 expression, and these were reversed by transfection of miR-126 mimics. Rescue tests using miR-126 and HIF-1α demonstrated that miR-126-mediated regulation of angiogenesis was dependent on HIF-1α. In summary, miR-126 regulates the occurrence and progression of angiogenesis during MI via HIF-1α and may be a potential new therapeutic target. [ABSTRACT FROM AUTHOR]