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Objective: The aim of this study was to compare the clinical efficacy of the full-endoscopic posterior cervical foraminotomy (FE-PCF) and the unilateral biportal endoscopic posterior cervical foraminotomy (UBE-PCF) in the treatment of cervical spondylotic radiculopathy (CSR). Methods: Patients who underwent posterior cervical spine surgery in our hospital from January 2020 to December 2022 were retrospectively analyzed. According to the surgical method, the patients were divided into two groups: FE-PCF group and UBE-PCF group. Perioperative data included operation time, Intraoperative blood loss and postoperative hospital stay were collected. The Visual Analog Scale (VAS)-arm, VAS-neck, and Neck Diability Index (NDI) was used to evaluate the clinical outcomes at preoperative, postoperative 1 week and Last follow-up. Serum creatine phosphokinase (CPK) and C-reactive protein (CRP) levels were recorded to evaluate surgical invasiveness. Results: A total of 160 patients were included, including 89 cases of FE-PCF and 71 cases of UBE-PCF. The demographic and preoperative data showed no significant differences between the two groups (P > 0.05). The mean operating time was significantly shorter in the UBE-PCF group compared to FE-PCF group (P < 0.05). Serum CRP and CPK levels of the two groups both exhibited a pattern of rising and then falling, peaking one day following surgery and decreasing to near normal values three days after the operation. Compared with preoperative, both groups showed significant improvement in postoperative VAS and NDI scores, with a statistically significant difference (P < 0.05). However, the differences in results between the groups were not significant. Conclusions: Both UBE-PCF and FE-PCF are secure and efficient methods for treating CSR by continuous visualization. UBE-PCF offers predictable and adequate decompression within a reduced surgical duration, facilitated by its separate observation and operation channels. [ABSTRACT FROM AUTHOR]

Purpose: To compare the clinical efficacy of mini-open (air/water medium) endoscopy-assisted anterior cervical discectomy and fusion (MOEA-ACDF) and anterior cervical decompression and fusion (ACDF) for cervical spondylotic myelopathy (CSM). Methods: This study retrospectively analysed the clinical data of CSM patients who received surgical treatment from January 1, 2020, to December 31, 2022. Patients were divided into two groups according to the surgical method: the MOEA-ACDF group and the ACDF group. The preoperative and postoperative imaging results at one week and the last follow-up examination were compared between the two groups. The Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) score and neck disability index (NDI) score were used to evaluate the clinical outcomes preoperatively, one week postoperatively and at the last follow-up examination. The minimum follow-up duration was 12 months. Results: A total of 131 CSM patients who underwent surgery at our institution were included, including 61 patients in the MOEA-ACDF group and 70 patients in the ACDF group. In the MOEA-ACDF group, the postoperative C2-C7 Cobb angle and HAVB were significantly greater than the preoperative values (P < 0.05). In the ACDF group, the postoperative C2-C7 Cobb angle was also significantly greater than the preoperative value, and the C2-C7 ROM and HAVB significantly decreased (P < 0.05). The postoperative neurological function of the patients in both groups improved, and the postoperative VAS score and NDI score significantly decreased. Compared with ACDF, MOEA-ACDF is associated with a significantly larger postoperative C2-C7 Cobb angle and significantly better C2-C7 ROM and HAVB, as well as better clinical efficacy (P < 0.05). Conclusions: MOEA-ACDF combines endoscopic systems with ACDF technology to treat CSM, but its clinical efficacy is not inferior to that of ACDF in the short- to intermediate-term. It can effectively and safely restore the cervical intervertebral height, physiological curvature, and range of motion. [ABSTRACT FROM AUTHOR]

This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment castings. The findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower temperature. The optimal conditions for solution treatment are determined as a solution temperature of 1,125 °C and a holding time of 5.0 min. Under these parameters, the size and volume fraction of precipitated phases in the investment castings are measured as 6.2 µm and 1.1vol.%. The yield strength, ultimate tensile strength, and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa, 760 MPa, and 12.6%, respectively. These values exceed those obtained with the conventional solution treatment at 1,200 °C for 4.0 h. The findings suggest a phase transformation of M23C6s+C following the current solution treatment at 1,125 °C for 5.0 min. In comparison, the traditional solution treatment at 1,200 °C for 4.0 h leads to the formation of M23C6 and M6C carbides. It is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation phase. This modification lowers the phase transition temperature of the M23C6s+C reaction, thereby facilitating the dissolution of carbides. As a result, the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods. [ABSTRACT FROM AUTHOR]

Behçet's syndrome (BS) is a variant vasculitis that can involve multiple organs with inflammatory manifestations. This study aimed to provide a more comprehensive analysis of the clinical phenotypes and characteristics of BS patients. We enrolled 2792 BS patients referred from China nationwide to Huadong Hospital Affiliated to Fudan University from October 2012 to December 2022. Detailed assessments of demographic information, clinical manifestations, laboratory results, gastroscopy, and medical imaging were conducted. Cluster analysis was performed based on 13 variables to determine the clinical phenotypes, and each phenotype was characterized according to the features of BS patients. A total of 1834 BS patients were included, while 958 invalid patients were excluded. The median age at onset was 31 years (IQR, 24–40 years), and the median disease duration was 10 years (IQR, 5–15 years). Eight clusters were identified, including mucocutaneous (n = 655, 35.7%), gastrointestinal (n = 363, 19.8%), articular (n = 184, 10%), ocular (n = 223, 12.2%), cardiovascular (n = 119, 6.5%), neurological (n = 118, 6.4%), vascular (n = 114, 6.2%), and hematological phenotype (n = 58, 3.2%). Ocular (RR = 1.672 (95% CI, 1.327–2.106); P < 0.001), gastrointestinal (RR = = 1.194 (95% CI, 1.031–1.383); P = 0.018), cardiovascular (RR = = 2.582 (95% CI, 1.842–3.620); P < 0.001), and vascular (RR = = 2.288 (95% CI, 1.600–3.272); P < 0.001) involvement were more prevalent in male BS patients, while the hematological (RR = 0.528 (95% CI, 0.360–0.776); P = 0.001) involvement was more common among female patients. BS presents significant heterogeneity and gender differences. The eight phenotypes of BS patients we propose hold the potential to assist clinicians in devising more personalized treatment and follow-up strategies. Key Points • This cluster analysis divided adult-onset BS into eight clinical phenotypes. • BS demonstrates a high level of clinical heterogeneity and gender differences. • Hematologic phenotypes of BS present distinctive clinical characteristics. [ABSTRACT FROM AUTHOR]

Objectives: Intimal hyperplasia is a serious clinical problem associated with the failure of therapeutic methods in multiple atherosclerosis-related coronary heart diseases, which are initiated and aggravated by the polarization of infiltrating macrophages. The present study aimed to determine the effect and underlying mechanism by which tumor necrosis factor receptor-associated factor 5 (TRAF5) regulates macrophage polarization during intimal hyperplasia. Methods: TRAF5 expression was detected in mouse carotid arteries subjected to wire injury. Bone marrow-derived macrophages, mouse peritoneal macrophages and human myeloid leukemia mononuclear cells were also used to test the expression of TRAF5 in vitro. Bone marrow-derived macrophages upon to LPS or IL-4 stimulation were performed to examine the effect of TRAF5 on macrophage polarization. TRAF5-knockout mice were used to evaluate the effect of TRAF5 on intimal hyperplasia. Results: TRAF5 expression gradually decreased during neointima formation in carotid arteries in a time-dependent manner. In addition, the results showed that TRAF5 expression was reduced in classically polarized macrophages (M1) subjected to LPS stimulation but was increased in alternatively polarized macrophages (M2) in response to IL-4 administration, and these changes were demonstrated in three different types of macrophages. An in vitro loss-of-function study with TRAF5 knockdown plasmids or TRAF5-knockout mice revealed high expression of markers associated with M1 macrophages and reduced expression of genes related to M2 macrophages. Subsequently, we incubated vascular smooth muscle cells with conditioned medium of polarized macrophages in which TRAF5 expression had been downregulated or ablated, which promoted the proliferation, migration and dedifferentiation of VSMCs. Mechanistically, TRAF5 knockdown inhibited the activation of anti-inflammatory M2 macrophages by directly inhibiting PPARγ expression. More importantly, TRAF5-deficient mice showed significantly aggressive intimal hyperplasia. Conclusions: Collectively, this evidence reveals an important role of TRAF5 in the development of intimal hyperplasia through the regulation of macrophage polarization, which provides a promising target for arterial restenosis-related disease management. [ABSTRACT FROM AUTHOR]

Brachial plexus avulsion (BPA) is a combined injury involving the central and peripheral nervous systems. Patients with BPA often experience severe neuropathic pain (NP) in the affected limb. NP is insensitive to the existing treatments, which makes it a challenge to researchers and clinicians. Accumulated evidence shows that a BPA-induced pain state is often accompanied by sympathetic nervous dysfunction, which suggests that the excitation state of the sympathetic nervous system is correlated with the existence of NP. However, the mechanism of how somatosensory neural crosstalk with the sympathetic nerve at the peripheral level remains unclear. In this study, through using a novel BPA C7 root avulsion mouse model, we found that the expression of BDNF and its receptor TrκB in the DRGs of the BPA mice increased, and the markers of sympathetic nervous system activity including α1 and α2 adrenergic receptors (α1-AR and α2-AR) also increased after BPA. The phenomenon of superexcitation of the sympathetic nervous system, including hypothermia and edema of the affected extremity, was also observed in BPA mice by using CatWalk gait analysis, an infrared thermometer, and an edema evaluation. Genetic knockdown of BDNF in DRGs not only reversed the mechanical allodynia but also alleviated the hypothermia and edema of the affected extremity in BPA mice. Further, intraperitoneal injection of adrenergic receptor inhibitors decreased neuronal excitability in patch clamp recording and reversed the mechanical allodynia of BPA mice. In another branch experiment, we also found the elevated expression of BDNF, TrκB, TH, α1-AR, and α2-AR in DRG tissues from BPA patients compared with normal human DRGs through western blot and immunohistochemistry. Our results revealed that peripheral BDNF is a key molecule in the regulation of somatosensory-sympathetic coupling in BPA-induced NP. This study also opens a novel analgesic target (BDNF) in the treatment of this pain with fewer complications, which has great potential for clinical transformation. [ABSTRACT FROM AUTHOR]

An aging method assisted by electric current was applied to a Fe-18Mn-9Al-1C (wt.%) low-density steel. It improves the microstructure and therefore significantly increases both the yield strength and ductility of the steel. This current-assisted aging method can increase the yield strength by 178 MPa and elongation by 1.16 times in only 0.5 min at 450 °C. However, the yield strength is increased only 90 MPa by the traditional aging method (heat conduction) at 450 °C for 180 min, and the elongation is even decreased from 42.0% to 31.6%. The obvious improvement in yield strength by the current-assisted aging for a short time is resulted from the fact that the current-assisted aging promotes a rapid precipitation of nano-scale κ-carbides in γ-austenite by reducing the thermodynamic barrier and accelerating the atomic diffusion. This work demonstrates that this current-assisted aging method is significantly time saving and cost-effective for low-density steels, with potential for various industrial applications. [ABSTRACT FROM AUTHOR]

Main conclusion: NB-LRR genes in the three Solanum species showed specific constitution characteristics and evolved multiple clusters and duplicates. Some genes could respond to biotic stresses such as tomato bacterial wilt. Nucleotide-binding and leucine-rich repeat (NB-LRR, NLR) is a largest resistance gene family in plants, which plays a key role in response to biotic stresses. In this study, NB-LRR genes in cultivated tomato Solanum lycopersicum (Sl) and its wild relatives S. pennellii (Spe) and S. pimpinellifolium (Spi) were analyzed using bioinformatics approaches. In total, 238, 202 and 217 NB-LRR genes of 8 different types were found in Sl, Spe and Spi, respectively. The three species showed similar genomic characteristics. The NB-LRR genes were mainly distributed on chromosomes 4, 5 and 11 and located at the distal zones, forming multiple clusters and tandem duplicates. A large number of homologs appeared through gene expansion, with most Ka/Ks values being less than 1, indicating that purifying selection had occurred in evolution. These genes were mainly expressed in root and could respond to different biotic stresses. RT-qPCR analysis revealed that SlNLR genes could respond to tomato bacterial wilt, with SlNLR1 probably involved in the resistance response, whereas others being the opposite. The transcription factors (TFs) and interaction proteins that regulate target genes were mainly Dof, NAC and MYB families and kinases. The results provide a basis for the isolation and application of related genes in plant disease resistance breeding. [ABSTRACT FROM AUTHOR]

Wood-based panels containing urea-formaldehyde resin result in the long-term release of formaldehyde and threaten human health. In this study, inorganic aluminosilicate coatings prepared by combining metakaolin, silica fume, NaOH, and H2O were applied to the surfaces of wood-based panels to obstruct formaldehyde release. The Si/Al, Na/Al, and H2O/Na2O molar ratios of the coatings were regulated to investigate their effects on the structure and formaldehyde-resistant barrier properties of coatings. Results showed that the cracks in the coatings gradually disappeared and the formaldehyde resistance rates of the barrier increased as the Si/Al molar ratio was increased from 1.6 to 2.2. This value also increased as the Na/Al molar ratio was increased from 0.9 to 1.2 because of the improvement of the degree of polymerization. As the H2O/Na2O molar ratio was increased from 12 to 15, the thickness of the dry film decreased gradually and led to the reduction in the formaldehyde resistance rate. When the Si/Al, Na/Al, and H2O/Na2O molar ratios were 2.2, 1.2, and 12, respectively, the inorganic aluminosilicate coating showed good performance as a formaldehyde-resistant barrier and its formaldehyde resistance rate could reach up to 83.2%. [ABSTRACT FROM AUTHOR]

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Reservoir evaluation of tight sandstone involves the determination of reservoir properties from samples and logs. In the calculation of water saturation, Archie formula is an important fundamental and connection between log evaluation and petrophysics. Highly accurate parameters of Archie formula are the key to the log evaluation of gas-bearing tight sandstone. At present, there are two methods of the rock-electric experiment to measure parameters of Archie formula: water increment (imbibition) and water decrement (centrifugation). In this paper the experimental measurement of a group of tight sandstone has been designed and the results of the two experimental ways are quite different. In the experiment, the distribution of brine is a main factor affecting the electrical properties of rocks. Fluid distribution model during imbibition and drainage is used to explain the results of rock electrical experiments, and the results are verified by nuclear magnetic resonance measurement. In the end, the Pickett chart method of actual data is used to compute the ranges of the saturation exponent n approximately, then to verify the correctness of the theoretical analysis. The results demonstrate that the centrifugal method is more applicable. In the log evaluation of tight sandstone, the appropriate choice of the method which can get accurate rock electrical parameters is important. Reliable evaluation will provide support for future development of gas-bearing tight sandstone. [ABSTRACT FROM AUTHOR]

The visibility of the underwater image is reduced due to the backscattering and signal attenuation, especially in highly turbid media. In this paper, we propose a polarization-based underwater image restoration method using logarithmic transformation and dark channel. Logarithmic transformation is first performed while maintaining the degree of polarization of the scene to increase the details of the images. Then we calculate the backscatter value through dark channel to estimate the degree of polarization of backscatter. The restored image can be obtained by the polarimetric recovery method. The experimental results illustrate the capabilities of the proposed method. Document code: A Article ID: 1673-1905(2020)02-0149-5 [ABSTRACT FROM AUTHOR]

Polymer films composed of thermoplastic polyurethane (TPU), poly (methyl methacrylate) (PMMA), and titania were developed by solution-casting method. Accordingly, gel polymer electrolytes (GPEs) were prepared by soaking the films in commercial liquid electrolytes for 8 h. The prepared GPEs could fix the liquid electrolytes inside and kept the shape stable. The hybrid GPEs exhibited a maximum ionic conductivity of 3.9 × 10−3 S‌‌‍ cm−1 at room temperature, with an electrochemical stability of up to 4.8 V versus Li+/Li. The compatibility test demonstrated that the introduction of PMMA and TiO2 improved the interfacial compatibility between lithium and GPEs. In battery test, the Li/GPE/LiFePO4 cell delivered the first discharge capacity of 169.2 mAh g−1 at 0.1 C and stable cycle performance (the retention of capacity is nearly 92% after 60 cycles) with high coulombic efficiency. All results demonstrated that the hybrid GPE was promising to satisfy the application in the future. [ABSTRACT FROM AUTHOR]

The effect of structural parameters such as contact width, low-angle, high-angle, interference and waist depth on the sealing performance of rotary lip seal was analyzed by finite element method. Based on the macroscopic pumping effect model of the rotary shaft lip seal and the pumping rate equation, the influence of structural parameters on pumping rate was calculated and analyzed. The structural and operational parameters of lip seal were optimized by the response surface method. 32 kinds of the model were made by compounding levels on each factor, and the response surface regression characteristics of each model are analyzed. The results show that low-angle, high-angle and interference are the main factors that influence significantly the seal performance of rotary shaft lip seal, and contact width, low-angle and high-angle are major influential factors for pumping effect. Therefore, these factors are considered as the most important factors for an optimum design of the rotary shaft lip seal. The optimal conditions are obtained, and the results are also verified by analytical methods. [ABSTRACT FROM AUTHOR]

Background and Objective: Lysophosphatidic acid (LPA) has widely been reported to participate in the numerous biological behaviors of tumors through its receptors. LPA receptor 6 (LPAR6) is a newly identified G protein-coupled receptor of LPA, and few studies have explored the role of LPAR6 in cancer. In breast cancer (BC), LPAR6 has not, as yet, been studied. This study aimed to evaluate LPAR6 expression in BC patients and to explore its possible role in BC.Methods: A total of 98 pairs of clinical BC and para-cancer tissues were collected, and LPAR6 expression was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Kaplan-Meier plots were employed for survival analysis. Human BC cell lines were cultured to study decitabine (5-aza-2ʹ-deoxycytidine [5-Aza]) intervention. Bioinformatic analyses were carried out to support the study conclusions and predictions.Results: LPAR6 expression was significantly reduced in BC tissues (p < 0.001). In the analysis of clinical parameters, LPAR6 expression was related to BC molecular classification (p < 0.05). Furthermore, patients with higher LPAR6 expression had better prognoses (p < 0.001). The CpG islands of LPAR6 were hypermethylated in BC tissues relative to those in para-cancer tissues (p < 0.01). 5-Aza significantly upregulated LPAR6 expression in BC cell lines. Additionally, LPAR6 knockdown significantly promoted cell migration and proliferation in the ZR-75-1 cell line (p < 0.001). Finally, through Gene Set Enrichment Analysis (GSEA), LPAR6 was found to be negatively correlated with cancer-promoting factors and positively correlated with tumor-suppressing factors.Conclusion: LPAR6 was downregulated in BC, and low LPAR6 expression was related to poor prognosis. The anti-tumor drug 5-Aza significantly upregulated LPAR6 expression in vitro, and LPAR6 might act as a tumor suppressor in BC. [ABSTRACT FROM AUTHOR]

Thanks to the emerging 3D integration technology, The multiprocessor system on chips (MPSoCs) can now integrate more IP cores on chip with improved energy efficiency. However, several severe challenges also rise up for 3D ICs due to the die-stacking architecture. Among them, power supply noise becomes a big concern. In the paper, we investigate power supply noise (PSN) interactions among different cores and tiers and show that PSN variations largely depend on task assignments. On the other hand, high integration density incurs a severe thermal issue on 3D ICs. In the paper, we propose a novel task scheduling framework considering both the PSN and the thermal issue. It mainly consists of three parts. First, we extract current stimuli of running tasks by analyzing their power traces derived from architecture level simulations. Second, we develop an efficient power delivery network (PDN) solver to evaluate PSN magnitudes efficiently. Third, we propose a heuristic algorithm to solve the formulated task scheduling problem. Compared with the state-of-the-art task assignment algorithm, the proposed method can reduce PSN by 12% on a 2 × 2 × 2 3D MPSoCs and by 14% on a 3 × 3 × 3 3D MPSoCs. The end-to-end task execution time also improves as much as 5.5% and 7.8% respectively due to the suppressed PSN. [ABSTRACT FROM AUTHOR]

Excessive forces may cause root resorption and insufficient forces would introduce no effect in orthodontics. The objective of this study was to investigate the optimal orthodontic forces on a maxillary canine, using hydrostatic stress and logarithmic strain of the periodontal ligament (PDL) as indicators. Finite element models of a maxillary canine and surrounding tissues were developed. Distal translation/tipping forces, labial translation/tipping forces, and extrusion forces ranging from 0 to 300 g (100 g=0.98 N) were applied to the canine, as well as the force moment around the canine long axis ranging from 0 to 300 g·mm. The stress/strain of the PDL was quantified by nonlinear finite element analysis, and an absolute stress range between 0.47 kPa (capillary pressure) and 12.8 kPa (80% of human systolic blood pressure) was considered to be optimal, whereas an absolute strain exceeding 0.24% (80% of peak strain during canine maximal moving velocity) was considered optimal strain. The stress/strain distributions within the PDL were acquired for various canine movements, and the optimal orthodontic forces were calculated. As a result the optimal tipping forces (40-44 g for distal-direction and 28-32 g for labial-direction) were smaller than the translation forces (130-137 g for distal-direction and 110-124 g for labial-direction). In addition, the optimal forces for labialdirection motion (110-124 g for translation and 28-32 g for tipping) were smaller than those for distal-direction motion (130-137 g for translation and 40-44 g for tipping). Compared with previous results, the force interval was smaller than before and was therefore more conducive to the guidance of clinical treatment. The finite element analysis results provide new insights into orthodontic biomechanics and could help to optimize orthodontic treatment plans. [ABSTRACT FROM AUTHOR]

Brownmillerite-type oxides BaInMnAlO (0 ≤ x ≤ 0.6, 0 ≤ y ≤ 0.5) were prepared at 1300°C through solid-state reaction. X-ray diffraction (XRD) analysis showed that the structure symmetry evolved from orthorhombic to cubic with increasing Mn and Al contents. When y was greater than 0.3, peaks associated with small amounts of BaAlO and BaInAlO impurities were observed in the XRD patterns. When substituted with a small amount of Mn ( x ≤ 0.3), the BaInMnAlO samples exhibited an intense turquoise color. The color changed to green and dark-green with increasing Mn concentration. UV-vis absorbance spectra revealed that the color changed only slightly upon Al doping. The valence state of Mn ions in BaInMnAlO was confirmed to be +5 on the basis of X-ray photoelectron spectroscopic analysis. According to this analysis, the intense turquoise color of the BaInMnAlO samples is rooted in the existence of Mn; thus, the introduction of Al does not affect the optical properties of the compounds. [ABSTRACT FROM AUTHOR]

For a high-speed railway bridge built in soft soil, excessive settlement can seriously affect the railway safety of operation. So, how to strictly control the settlement has become a common concern in this filed. As a new type of bridge foundation, Lattice Shaped Diaphragm Wall (hereinafter for LSDW) provides a potential new solution to this problem. In order to investigate the applicability of LSDW as bridge foundations in soft soil, three models (pile group, LSDWs with single chamber and two chambers) under similar material quantity are studied by small-scale model tests and numerical analysis based on FLAC3D. The settlement, skin friction, soil resistance under cap and load sharing ratio of three models are studied thoroughly, and special attention is given to the investigation of the settlement difference of three models under similar material quantity. It turns out to be that the bearing capacity will be improved and the settlement will be reduced for a practical bridge foundation if it can adopt LSDWs instead of pile group in soft soil. [ABSTRACT FROM AUTHOR]

In view of the fact that large scale vortices play the substantial role of momentum transport in turbulent flows, large eddy simulation (LES) is considered as a better simulation model. However, the sub-grid scale (SGS) models reported so far have not ascertained under what flow conditions the LES can lapse into the direct numerical simulation. To overcome this discrepancy, this paper develops a swirling strength based the SGS model to properly model the turbulence intermittency, with the primary characteristics that when the local swirling strength is zero, the local sub-grid viscosity will be vanished. In this paper, the model is used to investigate the flow characteristics of zero-incident incompressible turbulent flows around a single square cylinder (SC) at a low Reynolds number range Re ∈ [10, 10]. The flow characteristics investigated include the Reynolds number dependence of lift and drag coefficients, the distributions of time-spanwise averaged variables such as the sub-grid viscosity and the logarithm of Kolmogorov micro-scale to the base of 10 at Re = 2 500 and 10, the contours of spanwise and streamwise vorticity components at t = 170. It is revealed that the peak value of sub-grid viscosity ratio and its root mean square (RMS) values grow with the Reynolds number. The dissipation rate of turbulent kinetic energy is larger near the SC solid walls. The instantaneous factor of swirling strength intermittency (FSI) exhibits some laminated structure involved with vortex shedding. [ABSTRACT FROM AUTHOR]

The combined T junctions used for the oil-water separation have the advantages of compactness in structure, consistency in effects and economy in cost. The mixture k?? turbulence model and the Eulerian multi-fluid model are used to simulate the flow and phase distribution in the combined T junctions. The effects of structural parameters such as the branched pipe interval and height on the flow distribution and the separation behaviors are studied. The results show that the combined T junctions under fixed inlet and outlet boundary conditions form a single hydraulic equilibrium system in which the fluid energy distributes freely till a balance is achieved. The split-flow promotes the separation of the immiscible oil and the water. The separation efficiency increases with the increase of the branched pipe interval and changes slightly with the increase of the branched pipe height. The structural change of the combined T junctions may change the flow direction in the branched pipes. Simulation results can provide some guidance for the design of the combined T junctions as one kind of oil-water separator. [ABSTRACT FROM AUTHOR]

Existed evidences show that airborne transmission of human respiratory droplets may be related with the spread of some infectious disease, such as severe acute respiratory syndrome (SARS) and H1N1 pandemic. Non-pharmaceutical approaches, including ventilation system and personal protection, are believed to have certain positive effects on the reduction of co-occupant's inhalation. This work then aims to numerically study the performances of mouth covering on co-occupant's exposure under mixing ventilation (MV), under-floor air distribution (UFAD) and displacement ventilation (DV) system, using drift-flux model. Desk partition, as one generally employed arrangement in plan office, is also investigated under MV. The dispersion of 1, 5 and 10 μm droplet residuals are numerically calculated and CO is used to represent tracer gas. The results show that using mouth covering by the infected person can reduce the co-occupant's inhalation greatly by interrupting direct spread of the expelled droplets, and best performance can be achieved under DV since the coughed air is mainly confined in the microenvironment of the infected person. The researches under MV show that the two interventions, mouth covering and desk partition, achieve almost the same inhalation for fine droplets while the inhalation of the co-occupant is lower when using mouth covering for large droplets. [ABSTRACT FROM AUTHOR]

The main objectives were to (1) calculate the total volatile organic compounds (TVOCs) inhalation dose, (2) analyze the proportions of human’s inhaled contaminant dose from different sources, and (3) present a newly defined ratio of relative inhalation dose level (RIDL) to assess indoor air quality (IAQ). A user defined function based on CFD (computational fluid dynamics) was developed, which integrated human motion model with TVOCs emission model in a high sidewall air supply ventilation mode. Based on simulation results of 10 cases, it is shown that the spatial concentration distribution of TVOCs is affected by human motion. TVOCs diffusion characteristic of building material is the most effective way to impact the TVOCs inhalation dose. From the RIDL index, case A-2 has the most serious IAQ problem, while case D-1 is of the best IAQ. [ABSTRACT FROM AUTHOR]

Abstract  Seedlings with four true leaves of cucumbers (Cucumis sativus L.), Guonong No.25 (a cold-tolerant cultivar) and Guonong No.41 (a cold sensitive cultivar), were grown under normal or low temperature conditions: 25°C/18°C or 15°C/8°C (day/night). The seedlings of Guonong No.25 under low temperature were also treated with or without exogenous ABA. The purpose of our study was to find out the effects of low temperature and exogenous ABA application on the carbohydrate metabolism in the cucumber plants. Time course changes of carbohydrate contents and activities of stachyose synthase and alkaline α-galactosidase in the seedling leaves were investigated after the treatment. Our results show that compared to the seedlings under temperatures of 25°C/18°C, the seedlings of the both tested genotypes under 15°C/8°C (day/night) have significantly higher contents of all measured soluble carbohydrates. Significant difference in stachyose synthase activity is observed between the two genotypes under normal temperature or low temperature. Under normal temperature, leaf stachyose synthase activity in Guonong No.41 is higher than that in Guonong No.25. The stachyose synthase activity of Guonong No.41 decreases sharply under low temperature, but that of Guonong No.25 increases 3 days after treatment and then decreases to the original level. In contrast, there is no significant genotypic difference in alkaline α-galactosidase activity. Additionally, compared to the control seedlings treated with 0 μM ABA, the seedlings treated with 50 and 150 μM ABA accumulate substantial amounts of all tested soluble carbohydrates except galactose whereas 250 μM ABA treated seedlings show decreased levels of all these soluble carbohydrates. Stachyose synthase activity increases significantly upon 50 and 150 μM ABA treatments. [ABSTRACT FROM AUTHOR]

The recent sequencing of the DNA region of the geldanamycin post-polyketide synthase (PKS) modification gene clusters revealed the presence of two regulatory genes: gdmRI (2,907 bp) and gdmRII (2,766 bp). The deduced products of gdmRI and gdmRII (968 and 921 amino acid residues, respectively) were identified as homologues of the LuxR transcriptional regulatory proteins. Inactivation by gene replacement of gdmRI or gdmRII in the Streptomyces hygroscopicus 17997 genome resulted in a complete loss of geldanamycin production. Complementation by a plasmid carrying gdmRI or gdmRII restored geldanamycin production, suggesting that the products of these two regulatory genes are positive regulators that are required for geldanamycin biosynthesis. The gdmRI transcript was detected in the Δ gdmRII mutant, and the gdmRII was detected in the Δ gdmRI mutant, indicating that the two genes are transcribed independently and do not regulate each other. Time course of gene expression analysis by RT-PCR of the geldanamycin biosynthetic genes showed that the transcription of gdmRI and gdmRII correlates with that of genes involved in polyketide biosynthesis, but not with the post-PKS modification gene gdmN, whose transcription is initiated earlier. gdmRI or gdmRII gene disruptants did not transcribe the polyketide biosynthetic related genes pks, gdmF, and gdnA-O-P, but did trancribe gdmN. These results demonstrated that gdmRI and gdmRII are pathway-specific positive regulators that control the polyketide biosynthetic genes in geldanamycin biosynthsis, but not the post-PKS modification gene, gdmN. [ABSTRACT FROM AUTHOR]

To the most of velocity fields, the traveltimes of the first break that seismic waves propagate along rays can be computed on a 2-D or 3-D numerical grid by finite-difference extrapolation. Under ensuring accuracy, to improve calculating efficiency and adaptability, the calculation method of first-arrival traveltime of finite-difference is derived based on any rectangular grid and a local plane wavefront approximation. In addition, head waves and scattering waves are properly treated and shadow and caustic zones cannot be encountered, which appear in traditional ray-tracing. The testes of two simple models and the complex Marmousi model show that the method has higher accuracy and adaptability to complex structure with strong vertical and lateral velocity variation, and Kirchhoff prestack depth migration based on this method can basically achieve the position imaging effects of wave equation prestack depth migration in major structures and targets. Because of not taking account of the later arrivals energy, the effect of its amplitude preservation is worse than that by wave equation method, but its computing efficiency is higher than that by total Green’s function method and wave equation method. [ABSTRACT FROM AUTHOR]

Background: Global environmental pollution caused by human activities has become a threat to public health. Children are especially susceptible to adverse environmental conditions owing to their unique physiological and behavioral characteristics. A number of studies have demonstrated associations between the incidence of some childhood diseases and adverse environmental conditions. Shanghai is the largest and most important economic center in China. After rapid population expansion in recent decades, the shortage of pediatric medical resources is becoming a serious public health problem. This study aimed to identify and characterize the social and environmental effect of adverse environmental conditions on overall pediatric admissions at hospitals in Shanghai, China.Methods: This was a multi-center study spanning from January, 2013 to November, 2014. Daily pediatric admission data (~ 12,000 overall pediatric admissions/day) of three tertiary pediatric hospitals were collected from the large-scale health information exchange network of Shanghai. We linked the admission data with local environmental data. A seasonal decomposition method was applied to a time-trend analysis of the admission data; a generalized additive model was applied to model the association between environmental measurements and admissions data.Results: Admissions to outpatient and emergency departments were highly influenced by calendar factors; however, these same factors showed opposite effects on different clinical departments. The effect of nitrogen dioxide was a 0.27% increase (95% confidence interval (CI) 0.23% to 0.32%) in outpatient admissions and 0.78% (95% CI 0.68% to 0.88%) increase in emergency admissions. Concentrations of fine particles ≤ 2.5 micrometers in diameter (PM2.5) and carbon monoxide (CO) showed multi-faceted effects on pediatric admissions. PM2.5 and CO concentrations were significantly associated with decreased current-day outpatient admissions but also significantly associated with increased current-day emergency admissions at all three hospitals.Conclusions: Based on the health information exchange network of Shanghai, we conducted a large-scale, multi-center retrospective study of the association between adverse environmental conditions and pediatric admissions. Our study contributes to environmental health research in children and may guide decision-making regarding pediatric resource planning and policies. [ABSTRACT FROM AUTHOR]

Objectives: Glass fiber reinforced shape memory polyurethane (GFRSMPU) has great potential to be an alternative kind of material for orthodontic archwires for overcoming the disadvantages of metal wires in terms of esthetic and allergy and deficiency of pure shape memory polyurethane (SMPU) wires in mechanical properties. The objective of this study was to investigate the thermo-mechanical properties and shape recovery functions of GFRSMPU and evaluate the feasibility of using this composite for orthodontic archwires. Material and methods: GFRSMPU were made from short cut glass fibers and SMPU by mixing extrusion. Scanning electron microscope (SEM) and differential scanning calorimetry (DSC) were performed to investigate the distribution of glass fibers in the mixture and glass transition temperature (Tg). Then the thermo-mechanical properties, including tensile modulus, flexural modulus and stress relaxation effects, were measured. Furthermore, shape recovery functions of GFRSMPU characterized by the shape recovery ratio and force were investigated through shape recovery tests, typodont models and finite element analysis (FEA). Results: SEM images indicated that an excellent dispersity of glass fibers was obtained after double-extrusion. DSC experiments showed Tg was not enormously affected with the existence of glass fibers, but the mechanical properties of GFRSMPU were greatly improved. Shape recovery tests showed reduction of shape recovery ratio of the GFRSMPU material with the addition of glass fibers, but dentition aligning time was reduced by 50% in the simulation performed on identical typodont models with GFRSMPU archwires filled with 30 wt.% glass fibers. The FEA results illustrated that the reacting forces of GFRSMPU archwires with 30 wt.% glass fiber was increased by 96.36% compared with pure SMPU archwires. Conclusions: The mechanical properties of GFRSMPU can be considerably improved by adding glass fibers, and the shape memory function would be well preserved too. Enhanced SMPU owns a good application prospect in orthodontics for dentation aligning on the preliminary stage, as well as other medical fields. [ABSTRACT FROM AUTHOR]