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In the study of evolution equations, the method of adiabatic approximation is an essential tool to reduce an infinite-dimensional dynamical system to a simpler, possibly finite-dimensional one. In this paper, we formulate a generic scheme of adiabatic approximation that is valid for an abstract nonlinear evolution under mild regularity assumptions. The key prerequisite for the scheme is the existence of what we call approximate solitons. These are some low energy but not necessarily stationary configurations. The approximate solitons are characterized by a number of parameters (possibly infinitely many) and have a manifold structure. The adiabatic scheme reduces the given abstract evolution equation to an effective equation on the manifold of approximate solitons. We give sufficient conditions for the approximate solitons so that the reduction scheme is valid up to a large time. The validity is determined by the energy property of the original evolution as well as the adiabaticity of the approximate solitons. [ABSTRACT FROM AUTHOR]

In this paper, we consider the concentration property of solutions to the dispersive Ginzburg-Landau (or Gross-Pitaevskii) equation in three dimensions. On a spatial domain, it has long been conjectured that such a solution concentrates near some curve evolving according to the binormal curvature flow, and conversely, that a curve moving this way can be realized in a suitable sense by some solution to the dispersive Ginzburg-Landau equation. Some partial results are known with rather strong symmetry assumptions. Our main theorems here provide affirmative answer to both conjectures under certain small curvature assumption. The results are valid for small but fixed material parameter in the equation, in contrast to the general practice to take this parameter to its zero limit. The advantage is that we can retain precise description of the vortex filament structure. The results hold on a long but finite time interval, depending on the curvature assumption. [ABSTRACT FROM AUTHOR]

Squeeze casting is a near net shaping technology which is advantageous to refining the microstructures and improving the mechanical properties. In the present work, in-situ Al3Ti/2024 Aluminum matrix composites with different amount of Al3Ti reinforcements were successfully fabricated by ultrasonic treatment and subsequent squeeze casting. The effects of specific pressure and the amount of reinforcements on microstructures and mechanical properties were studied. The results show that when the specific pressure is increased from 0 to 150 MPa, the average grain sizes of α-Al matrix are decreased by 39.8%, and the yield strength and compressive strength are increased by 16.8% and 22.9%, respectively. However, severe segregations of eutectic structures were generated under an excessive specific pressure of 200 MPa, which also results in deterioration in the mechanical strength. The mass fraction of Al3Ti phases has significant influence on morphology of eutectic structures. When the mass fraction of Al3Ti phases is increased from 4 to 16 wt%, the eutectic structures was changed from continuous network to dispersed structures gradually. The compressive strength was increased from 611.2 to 712.0 MPa (increased by 16.5%), as the Al3Ti content increasing from 0 to 16 wt%. However, as the mass fraction of Al3Ti phases increased, the variation in the yield strength is not monotonically increasing. [ABSTRACT FROM AUTHOR]

Objectives: To characterize a pyrazinamidase from non-pathogen Pseudonocardia carboxydivorans. Results: A pyrazinamidase gene pncA encoding a 23-kDa protein PncA-Pse from P. carboxydivorans was over-expressed in Escherichia coli and characterized. This PncA-Pse can convert both pyrazinamide and nicotinamide efficiently with the optimal pH and temperature of pH 8.5 and 45 °C, respectively. Although ferrous iron and manganese were detected in PncA-Pse, the enzymatic activity is not affected by EDTA with the final concentration of 10 mM. Moreover, the enzymatic activity was not significantly affected with the addition of several metal ions, respectively. Based on the structure modeling, the 61st histidine which is associated with the metal binding, was mutated into alanine to get mutant H61A. No activity, iron and manganese were detected for H61A, which implies that PncA-Pse is a metal enzyme with resistance of the metal ion chelator EDTA, which is different from the previous reports. Conclusion: This is the first characterized pyrazinamidase from the genus Pseudonocardia, a non-pathogen. [ABSTRACT FROM AUTHOR]

Conclusion: API directive is one of the most important knowledge in API specifications. Existing approach only relies on syntactic patterns to detect API directives and lacks a deep semantic understanding. In this study, we propose a deep learning approach DeepDir to automatically detect API directives. Experimental results show that DeepDir significantly improves the state-of-the-art approach by 20.78% on average in terms of F-measure. [ABSTRACT FROM AUTHOR]

Electrically assisted superplastic forming and diffusion bonding (EASPF/DB) is based on the electrically assisted technique in which the electric current is directly and simply introduced into metallic sheets during hot processing. Through the rapidly increasing heat by the Joule effect after several minutes, the advantages of the EASPF/DB process are further strengthened, and the limitations of commercial exploitation (e.g., long processing period) are partly overcome. In this study, an experimental setup of EASPF/DB was assembled for the experimental validation of this concept. The Ti2AlNb alloy sheet, which is regarded as a superior substitute for the nickel-based alloy, was diffusion-bonded and formed, and a double-layer structure was fabricated by means of the EASPF/DB process. The temperature distribution measured by an infrared imaging camera was apparently influenced by detour effects of the electric current. To examine the forming and bonding effects, the height and thickness were measured in different positions. The microstructures of the bonding interface were observed, and no microcavity and crack were found, which indicated the feasibility of the variant of the SPF/DB process. Meanwhile, the large-size grains of B2 phase compose the microstructure of forming zone with some fine needle–like precipitates. Finally, the hardness test showed higher values of Vickers hardness than that of the as-received sheet and the compression test showed three stages of the double-layer structure during continuous loading. The important values and significance for use of this variant are presented by markedly reducing the heating and cooling time and the targeted heating manner for metallic sheets. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the pathologic changes and pathogenesis of multikinase inhibitor (MKI)-induced skin lesions in an animal model.Methods: Tumor-bearing nude mice and BDF1 mice were treated with different doses (30-240 mg/kg, Bid) of sorafenib. The pathology and severity of the skin lesions was assessed and evaluated. The concentration of sorafenib in the skin was also determined.Results: Sorafenib transiently induced skin rash at high doses (120-240 mg/kg). The induced skin lesions had pathological manifestations resembling the observations in human patients. The skin of mice treated with sorafenib had significantly increased pathological scores and thickness of the stratum spinosum compared with the control, and induced more severe cutaneous lesions in nude mice than in BDF1 mice. The severity of skin lesions was correlated with the local concentration of sorafenib in the skin, which was significantly higher in nude mice than in BDF1 mice. Sorafenib treatment significantly increased the expression of F4-80, Ly6G, tumor growth factor (TGF)-1β, Smad2/3, α-smooth-muscle actin, and proliferating cell nuclear antigen.Conclusions: The severity of skin lesions was positively correlated with the concentration of sorafenib in the skin. Our results suggested the involvement of the TGF-β1/Smads signaling pathway in the skin reaction induced by MKIs. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is a promising antineoplastic modality in the oncology field. We assessed the safety of repeated intravenous administrations of sinoporphyrin, a porphyrin derivative, with and without illumination in rats. Toxicokinetic studies of single and multiple administrations of sinoporphyrin were also carried out. Sprague-Dawley rats were randomly assigned to the dark-toxicity and PDT groups. Animals in the dark toxicity group received an i.v. infusion of sinoporphyrin at 3 doses: 2 mg kg−1, 6 mg kg−1, and 18 mg kg−1. The PDT group included 2 doses of sinoporphyrin (2 mg kg−1 and 18 mg kg−1), and the rats received 60 J of 630 nm laser illumination 24 h after photosensitizer infusion. The treatments were repeated every 7 days for 5 cycles and were followed by a 14-day recovery period. Systematic analyses were conducted at the end of treatment and recovery periods. Blood samples were obtained 5 min, 30 min, 2 h, 8 h, 24 h, 48 h, 72 h, and 96 h after the first and fifth treatments for toxicokinetic studies. Sinoporphyrin-PDT led to the death of one out of 270 rats; the dead animal had been treated with 18 mg kg−1 sinoporphyrin and died at the end of the fifth PDT treatment. Liver injury, the primary toxicity observed in the study, was identified using biochemical tests, necropsy, and histopathology. Elevated white blood cell and neutrophil counts were found in the rats in both the dark toxicity and PDT groups. Skin lesions at the illumination site were obvious in the PDT group. Pigment deposits were detected in multiple organs such as the liver, spleen, lymph nodes, and ovaries in the 6 mg kg−1 and 18 mg kg−1 groups. No other abnormalities were observed. The toxicokinetic parameters of single and multiple sinoporphyrin administrations were calculated and compared. Repeated sinoporphyrin administrations both alone and in combination with laser illumination were tolerable, and all toxicities were transient. The no observed adverse effect level (NOAEL) for repeated sinoporphyrin administration and sinoporphyrin-PDT was 6 mg kg−1 and 2 mg kg−1, respectively. Further studies are warranted. [ABSTRACT FROM AUTHOR]

Purpose: While social integration among individuals with psychosis differs by social context, this has rarely been investigated across urban vs. rural settings. For individuals with psychosis, marriage may be a key component of social integration. This study aims to compare marriage outcomes for individuals with psychosis in urban vs. rural settings in China, where marriage has been almost universal among individuals without psychosis.Methods: In a large community-based study in four provinces representing 12% of China's population, we identified 393 individuals with psychosis (112 never treated). We used adjusted Poisson regression models to compare marriage status for those living in urban (n = 96) vs. rural (n = 297) contexts.Results: While urban and rural residents had similar impairments due to symptoms, urban female residents were 2.72 times more likely to be unmarried than their rural counterparts (95% CI 1.19-6.22, p < 0.0176). Stratified analyses indicated that this marital disadvantage occurred primarily among urban females with an earlier age of onset. No differences were found among males.Conclusions: Our findings indicate that urban contexts impeded opportunities for marriage for female individuals with psychosis. These data suggest that urban women with earlier age of onset have difficulty in marrying which may be related to economic expectations of women in urban areas. Research examining contextual mechanisms that affect marriage may further understanding of social integration in China and other contexts. [ABSTRACT FROM AUTHOR]

Sinoporphyrin sodium (DVDMS) is a novel hematoporphyrin-like photosensitizer developed for photodynamic therapy (PDT), an effective therapeutic modality for tumor treatment; however, the safety of photosensitizer-based PDT is always of great concern. The purpose of the current study was to investigate the potential repeated-dose toxicity and describe the toxicokinetic process of DVDMS-based PDT in Beagle dogs. The dogs were randomly allocated to six groups, and then were administrated a DVDMS preparation intravenously at dose levels of 0, 1, 3, 9, 1 and 9 mg per kg body weight, respectively; then, the latter two groups were illuminated 24 h later with a 630 nm laser for 10 min, once every seven days for 5 weeks. During the study period, clinical signs, mortality, body weight, food consumption, body temperature, ophthalmoscopy, hematology, serum biochemistry, urinalysis, electrocardiograms, toxicokinetics, organ weights, gross anatomy and histopathology were examined. After the administration, no deaths were observed; however, the dogs that received PDT showed skin swelling and ulceration, indicating that DVDMS-PDT induced a phototoxic effect. DVDMS led to an increase in blood coagulation in dogs in the 9 mg kg−1 group and in the two PDT groups on Day 35, whereas it induced a decrease in dogs in the 3 mg kg−1 group and in the two PDT groups on Day 49. The toxicokinetic study showed that the systematic exposure of DVDMS in dogs occurred in a dose-dependent manner, and DVDMS did not accumulate in blood plasma. The DVDMS-based PDT group showed no obvious treatment-related pathological changes; however, slight or mild brown-and-yellow pigmentation of DVDMS (or its metabolite) was observed to deposit in the liver, spleen, local lymph nodes and marrow of dogs in the mid- and high-dose groups, as well as the high-dose PDT group. In females, the absolute and relative spleen weights increased in dogs in the 9 mg kg−1 DVDMS groups with and without PDT during the treatment and recovery period, respectively. The target organs are presumed to be the liver and immune organs (spleen, bone marrow and lymph nodes), while all of the responses were slight. Based on the results above, the no-observed-adverse-effect level (NOAEL) was considered to be 1 mg kg−1, and DVDMS-PDT appeared to be a safe and promising anti-tumor therapy in the clinic. [ABSTRACT FROM AUTHOR]

Local search algorithms play an essential role in solving large-scale combinatorial optimization problems. Traditionally, the local search procedure is guided mainly by the objective function of the problem. Hence, the greedy improvement paradigm poses the potential threat of prematurely getting trapped in low quality attraction basins. In this study, we intend to utilize the information extracted from the relaxed problem, to enhance the performance of the local search process. Considering the Lin-Kernighan-based local search (LK-search) for the p-median problem as a case study, we propose the Lagrangian relaxation Assisted Neighborhood Search (LANS). In the proposed algorithm, two new mechanisms, namely the neighborhood reduction and the redundancy detection, are developed. The two mechanisms exploit the information gathered from the relaxed problem, to avoid the search from prematurely targeting low quality directions, and to cut off the non-promising searching procedure, respectively. Extensive numerical results over the benchmark instances demonstrate that LANS performs favorably to LK-search, which is among the state-of-the-art local search algorithms for the p-median problem. Furthermore, by embedding LANS into other heuristics, the best known upper bounds over several benchmark instances could be updated. Besides, run-time distribution analysis is also employed to investigate the reason why LANS works. The findings of this study confirm that the idea of improving local search by leveraging the information induced from relaxed problem is feasible and practical, and might be generalized to a broad class of combinatorial optimization problems. [ABSTRACT FROM AUTHOR]

A new method was developed for effective separation and simultaneous determination of estrogens, gestagens, and androgens, including estrone, 17β-estradiol, testosterone, progesterone, and estriol, in infant formula. The samples were enzymatically digested with β-glucuronidase/arylsulfatase prior to microwave-assisted extraction. After the extract was cleaned up by gel permeation chromatography the hormones were derivatived with 50 μL BSTFA containing 1 % TMCS. The derivatived hormones were measured with GC-MS/MS using electron impact ionization source in the positive multi-reaction monitoring mode. The calibration curves showed good linearity with correlation coefficient ( r) of >0.999. The limit of quantification of five hormones ranged from 0.094 to 0.265 μg kg, which is below the minimum required performance limits established by the European Community. The intra- and inter-day precision (as RSD) for six determinations of five analytes at 40 μg kg spiked level was in range of 3.4-5.4 % and 3.5-6.8 %, respectively. The recovery of five analytes was obtained to be 84.5-104 %, with relative standard deviations (RSD, n = 6) of 1.7-5.5 %. This method has been successfully used for the qualitatively and quantitatively determination of estrone, 17β-estradiol, testosterone, progesterone, and estriol in infant formula. [ABSTRACT FROM AUTHOR]

A novel ultrahigh performance liquid chromatographic method is developed for analysis of 21 synthetic colorants with different acid-base property, solubility, and polarity. The meat samples were extracted by microwave-assisted extraction followed by cleanup with solid-phase extraction. The effective separation of the colorants in meat matrixes was achieved, and no interfering peaks could be detected at the retention time of the analytes. The calibration curves showed good linearity with correlation coefficients of 0.9940-0.9999. The limits of quantification were 0.48-7.19 μg/kg. The average recovery of the 21 analytes from meat samples spiked with 25 and 75 μg kg was 61.29-116.1 % with relative standard deviation (RSD) of <11 %. For blank beef sausage spiked with 50 μg kg for each analyte, the intraday precision (as RSD) for 21 analytes was 1.45-9.21 % for six determinations within a day. This method has the advantages of being rapid, sensitive, accurate, and with high-throughput and can be applied for multiresidue analysis of meat samples, including six allowable azo food colorants, ten banned azo food colorants, four banned triphenylmethanes, and rhodamin B food colorant. [ABSTRACT FROM AUTHOR]

For convenience of both measurement and adjusting the clearance size and incidence, the current research is mainly conducted by experiments on an axial compressor linear cascade. The characteristics and the condition under which the unsteadiness of tip leakage flow would occur were investigated by dynamic measuring in different clearances, inlet velocities and incidences. From the experiment it is found that increasing tip clearance size or reducing rotor tip incidence can affect the strength of the tip clearance flow. Then the experimental results also indicate the tip leakage shows instability in certain conditions, and the frequency of unsteadiness is great influenced by inflow angle. The condition of occurrence of tip leakage flow unsteadiness is when the leakage flow is strong enough to reach the pressure side of the adjacent blade. The main cause of tip leakage flow unsteadiness is the tip blade loading. [ABSTRACT FROM AUTHOR]

A new method for multi-residue determination of five synthetic glucocorticoids (betamethasone, dexamethasone, prednisone, prednisolone, and hydrocortisone) in milk powder is developed. The glucocorticoids in the samples were extracted with tert-butyl methyl ether under ultrasonication incubation, and then cleaned up through gel permeation chromatography. After C18 LC gradient elution separation using acetonitrile with 0.1% formic acid as a mobile phase, the eluents were determined by liquid chromatography-tandem mass spectrometry with multiple reaction monitoring and positive ionization modes. The effective separation for the five glucocorticoids was achieved. The limit of quantification of the method for testing five glucocorticoids in milk powder was in the range from 0.2 to 0.5 μg kg, which was lower than the maximum residue limits established by European Union for glucocorticoids in foods. Experiments on spiked samples of milk powder showed that the mean recoveries at addition level of 1.0, 3.0, and 5.0 μg kg were in the range of 71.2% and 103%, and the relative standard deviation ranged from 4.7% to 16.8%. The calibration curves for these drugs between 1.0 and 100 μg l showed good linearity, with correlation coefficient ( r) more than 0.999. The real sample test showed that this method is sensitive and accurate. It can be used for qualitative and quantitative determination of studied glucocorticoid residues in milk powder samples. [ABSTRACT FROM AUTHOR]

n experimental investigation on the unsteady tip flow field of a transonic compressor rotor has been performed. The casing-mounted high frequency response pressure transducers were arranged along both the blade chord and the blade pitch. The chord-wise ones were used to indicate both the ensemble averaged and time varying flow structure of the tip region of the rotor at different operating points under 95% design speed and 60% design speed. The pitch-wise circumferential transducers were mainly used to analyze the unsteadiness frequency of the tip leakage flow in the rotor frame at the near stall condition. The contours of casing wall pressure show that there were two clear low pressure regions in blade passages, one along the chord direction, caused by the leakage flow and the other along the tangential direction, maybe caused by the forward swept leading edge. Both low pressure regions were originated from the leading edge and formed a scissor-like flow pattern. At 95% design speed condition, the shock wave interacted with the low pressure region and made the flow field unsteady. With the mass flow reduced, the two low pressure regions gradually contracted to the leading edge and then a spike disturbance emerged. [ABSTRACT FROM AUTHOR]

The benefits of programmed cell death by apoptosis are the safe and efficient clearance of damaged, infected, or surplus cells, primarily mediated by tissue-resident macrophages or tissue-infiltrating blood monocytes that differentiate into macrophages. Microglial cells are macrophages of the brain parenchyma, important immune surveillance cells that respond to various injuries and diseases of the brain. It is often stated that how a macrophage interacts with an apoptotic cell defines subsequent inflammatory responses, i.e., will engulfment be beneficial or detrimental for tissue repair, regeneration, and immunity. Our focus has been to better understand how macrophages discriminate between living and dying cells. Following our initial findings with platelet endothelial cell adhesion molecule (PECAM)-1, our studies have revealed a key role for potassium ion permeability in regulating integrin-dependent binding of apoptotic cells by macrophages and their subsequent response to proinflammatory stimuli. Specifically, apoptotic cells represent a depolarizing stimulus for macrophages where PECAM-1-mediated cell–cell interactions delay subsequent membrane repolarization. It is salient that potassium leak represents an early feature of cells destined to die by apoptosis that could trigger depolarization of macrophages that lie in close apposition. We speculate that how a tissue-resident macrophage responds to strong depolarizing stimuli has wider implications for inflammation and autoimmunity. [ABSTRACT FROM AUTHOR]

The stall behavior in a single-stage low-speed axial compressor under rotating inlet distortion (RID) is investigated in the first half of this paper. The tests demonstrate that the tip leakage flow (TLF) plays an important role in triggering rotating stall. The tracking of the spike-like disturbances caused by the spillage of TLV indicates that most of such spike-like disturbances will be smeared by non-distorted sector and the growth of the spike-like disturbances actually relate closely to how and how often the path of the propagating disturbances come across the path of the rotating distorted sector. In the second half of this paper, micro air injections are applied to test the effect behavior of TLF on stall inception. Contrasts to without micro air injections, the spike-like disturbances are much fewer, so the possibilities that spike-like disturbances may trigger rotating stall are fewer too. As a result, the compressor gets a lower mass flow rate at stall for both co-rotating inlet distortion and counter-rotating inlet distortion. [ABSTRACT FROM AUTHOR]

In multi-spool engines, the downstream compressor experiences a rotating inlet distortion if rotating stall occurs in upstream compressor, which may induce the instability of the whole compressor. In this paper, the compressor dynamic behavior is the major focus. The experiment was carried out on a single-stage low-speed axial-flow compressor. A rotating distortion generator equipped with different distortion sector(s) was designed to produce different rotating inlet distortion clockwise or counterclockwise with up to 100% of the compressor design speed. The distortion sector can be installed single or in some combination such as four sectors together. Three types of distortion sector/combination are used in the research work, which are single 30 degree sector, four 30 degree sectors and single 120 degree sector. It is found that the total pressure loss caused by rotating sector(s) increases when the distortion speed rises. For co-rotating distortions, all the three types of inlet distortion exhibited a peak in stall margin degradation when the distortion speed corresponded to roughly 50% of rotor speed. The two-dimensional numerical simulations of the compressor flow field clearly show the propagation of the disturbances trigged by the distortion sector(s). [ABSTRACT FROM AUTHOR]