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Both β-Ga2O3 and wurtzite AlN have wide bandgaps of 4.5–4.9 and 6.1 eV, respectively. We calculated the in-plane lattice mismatch between the (-201) plane of β-Ga2O3 and the (0002) plane of AlN, which was found to be 2.4%. This is the smallest mismatch between β-Ga2O3 and binary III-nitrides which is beneficial for the formation of a high quality β-Ga2O3/AlN heterojunction. However, the valence and conduction band offsets (VBO and CBO) at the β-Ga2O3/AlN heterojunction have not yet been identified. In this study, a very thin (less than 2 nm) β-Ga2O3 layer was deposited on an AlN/sapphire template to form the heterojunction by pulsed laser deposition. High-resolution X-ray photoelectron spectroscopy revealed the core-level (CL) binding energies of Ga 3d and Al 2p with respect to the valence band maximum in individual β-Ga2O3 and AlN layers, respectively. The separation between Ga 3d and Al 2p CLs at the β-Ga2O3/AlN interface was also measured. Eventually, the VBO was found to be -0.55±0.05 eV. Consequently, a staggered-gap (type II) heterojunction with a CBO of -1.75±0.05 eV was determined. The identification of the band alignment of the β-Ga2O3/AlN heterojunction could facilitate the design of optical and electronic devices based on these and related alloys. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the role of Bruton's tyrosine kinase (BTK) in the pathogenesis of lung injury induced by trauma-hemorrhagic shock (THS), and to examine the pulmonary protective effects of BTK inhibition. Male Sprague-Dawley rats were divided into four groups (n=12/group): i) A Sham group, which received surgery without induced trauma; ii) a THS-induced injury group; iii) a THS-induced injury group that also received treatment with the BTK inhibitor LFM-A13 prior to trauma induction; and iv) a Sham group that was pretreated with LFM-A13 prior to surgery but did not receive induced trauma. The expression of phosphorylated-BTK protein in the lungs was measured by immunohistochemistry and western blot analysis. The bronchoalveolar lavage fluid (BALF) protein concentration, total leukocyte and eosinophil numbers, and the expression levels of peripheral blood proinflammatory factors were measured. Morphological alterations in the lungs were detected by hematoxylin and eosin staining. Pulmonary nitric oxide (NO) concentration and inducible NO synthase (iNOS) expression were also assessed. Activities of the nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling pathways were determined by western blotting or electrophoretic mobility shift assay. BTK was notably activated in lungs of THS rats. BALF protein concentration, total leukocytes and eosinophils, peripheral blood expression levels of tumor necrosis factor-a, interleukin (IL)-1β, IL-6 and monocyte chemotactic protein 1 were significantly upregulated after THS induction, and each exhibited decreased expression upon LFM-A13 treatment. THS-induced interstitial hyperplasia, edema and neutrophilic infiltration in lungs were improved by the inhibition of BTK. In addition, THS-induced NO release, iNOS overexpression, and NF-κB and MAPK signaling were suppressed by BTK inhibition. Results from the present study demonstrate that BTK may serve a pivotal role in the pathogenesis of THS-related lung injury, and the inhibition of BTK may significantly alleviate THS-induced lung damage. These results provide a potential therapeutic application for the treatment of THS-induced lung injury. [ABSTRACT FROM AUTHOR]

The sodium leaching ratio (ηN) of ferric bauxite direct reduction process is much lower than that of ordinary bauxite; thus, the former consumes more sodium than the latter. ηN can be promoted by increasing the dosage of sodium or restricted by increasing the heating temperature and time. However, the restriction effect of heating temperature is 16.67 times larger than that of heating time, and the restriction effect decreases 47.03 times faster when heating temperature increases than that process of heating time. These imply that ηN improves with the increasing sodium carbonate dosage and the decreasing heating temperature. [ABSTRACT FROM AUTHOR]

Direct reduction is an emerging utilization technology of ferric bauxite. However, it requires much more sodium carbonate than ordinary bauxite does. The volatilization is one of the most significant parts of sodium carbonate consumption, as reported in previous studies. Based on the new direct reduction method for utilization of ferric bauxite, this paper has systematically investigated factors including heating temperature, heating time, and sodium carbonate dosage influencing sodium volatilization. For the purpose of reducing sodiumvolatilization, the Box--Benhken designwas employed, and the possibility of separating iron and sodium after direct reduction was also investigated. [ABSTRACT FROM AUTHOR]

Aim. To determine the anti-edema effects of melatonin on spinal cord injury (SCI) in rats. Methods. A total of 150 adult male Sprague-Dawley rats were randomly allocated to the following three groups (n=50): a sham group which underwent laminectomy without dural compression; an SCI group, which underwent laminectomy followed by SCI and received saline i.p. immediately after injury and then daily for 2 days; an MT group, which underwent laminectomy followed by SCI and received a 100 mg/kg dose of melatonin i.p. immediately after SCI and then daily for 2 days. The cords were removed at 12, 24, 48 and 72 h after surgery in every group. Spinal cord edema was evaluated by determining the spinal cord water content. Expressions of AQP4 and GFAP positive cells in injured spinal cord were detected by immunohistochemical staining, and protein expressions of AQP4 and GFAP were detected by Western blotting. Results. Spinal cord water content was obviously increased after SCI, which was maintained almost unchanged by melatonin treatment (100 mg/kg) at 12 h after injury but was significantly reduced from 24 h to 72 h. The expressions of AQP4 and GFAP increased in the injured spinal cord segments, which were decreased by melatonin treatment (100 mg/kg) between 24 h and 72 h after SCI. Conclusions. Melatonin (100 mg/kg) had anti-edema effects after acute SCI probably by down-regulating the expression level of AQP4 protein, and it may eliminate astrocytic swelling after SCI through down-regulating the expression level of GFAP protein. [ABSTRACT FROM AUTHOR]

Objective: To determine the association of SNP in FTO gene, rs9939609, with Metabolic Syndrome (MS) in type 2 diabetic subjects at a tertiary care unit of Karachi, Pakistan. Methods: We genotyped FTO rs9939609 SNP in 296 patients with type 2 diabetes from the Out Patient Department (OPD) of Baqai Institute of Diabetology and Endocrinology (BIDE). MS was defined on the basis of International Diabetes Federation (IDF) and National Cholesterol Education program (NCEP)criterion. Association between the rs9939609 SNP and MS was tested through chi-square and Z-tests by using odds ratio (OR) with 95% confidence intervals. Results:The frequency of MS as defined by IDF criterion was significantly higher in female subjects as compared to male subjects (p= 0.006). Carriers of = 1 copy of the rs9939609 A allele were significantly more likely to had MS (69.6%) than non-carriers (30.4%), corresponding to a carrier odds ratio (OR) of 0.52 (95% confidence interval [CI] (0.29-0.93), with a similar trend for the ATP III-defined MS."A" allele carriers under dominant model, carry all the criterion of MS more significantly as compared to non-carriers. Conclusion: The FTO rs9939609 SNP was associated with an increased risk for Metabolic Syndrome in type 2 diabetic populations at a tertiary care unit of Karachi, Pakistan. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) has been implicated in various human degenerative diseases. However, the role of mtDNA in Osteoarthritis (OA) is less known. To investigate whether mtDNA haplogroups contribute to the prevalence of knee OA, we have carried out a comprehensive case-control study on 187 knee OA patients and 420 geographically matched controls in southern China. OA patients were classified on the Kellgren/Lawrence scale from two to four for the disease severity study and the data were analyzed by adjusting for age and sex. We found that patients with haplogroup G (OR = 3.834; 95% CI 1.139, 12.908; p = 0.03) and T16362C (OR = 1.715; 95% CI 1.174, 2.506; p = 0.005) exhibited an increased risk of OA occurrence. Furthermore, patients carrying haplogroup G had a higher severity progression of knee OA (OR = 10.870; 95% CI 1.307, 90.909; p = 0.007). On the other hand, people with haplogroup B/B4 (OR = 0.503; 95% CI 0.283, 0.893; p = 0.019)/(OR = 0.483; 95% CI 0.245, 0.954; p = 0.036) were less susceptible for OA occurrence. Interestingly, we found OA patients also exhibited a general increase in mtDNA content. Our study indicates that the mtDNA haplogroup plays a role in modulating OA development. [ABSTRACT FROM AUTHOR]

Background: Nonunion of long bones in lower limbs is a common complication of orthopedic trauma that can be extremely debilitating. This retrospective study describes our experience using expandable intramedullary nails and autologous bone grafting in treating lower limb long bone nonunion with bone defects. Methods: Nineteen patients (mean age 38.9 years, range 18-61) with lower limb long bone nonunion and defects caused by femoral or tibial fracture types were as follows: A2 (3 femoral, 1 tibial), A3 (1 femoral, 2 tibial), B2 (3 femoral, 4 tibial), and B3 (1 femoral, 4 tibial). Expandable intramedullary nailing and autologous bone (iliac and/or fibular) grafting were used for the treatment. Postoperative bone healing as determined by analysis of standard anteroposterior and lateral X-ray films every 4 weeks. Complications were noted. Results: The average number of previous surgeries was 1.9 (range 1-4). The mean duration from original injury to treatment was 17.6 months (range 9-40 months). Femoral shaft nonunion healed on average of 26.5 weeks (range 16-60 weeks) after surgery, while tibial shaft nonunion healed on average of 23.6 weeks (range 12-40 weeks) after surgery. Class I healing occurred in all but two patients who experienced chronic postoperative osteomyelitis and delayed wound healing, respectively. Two patients complained of postoperative donor site pain. Conclusions: The use of expandable intramedullary nails and autologous bone grafts was an effective method for repair of nonunion of lower limb fractures combining with bone defects with minimal complications. [ABSTRACT FROM AUTHOR]

We present a null-space primal-dual interior-point algorithm for solving nonlinear optimization problems with general inequality and equality constraints. The algorithm approximately solves a sequence of equality constrained barrier subproblems by computing a range-space step and a null-space step in every iteration. The ℓ penalty function is taken as the merit function. Under very mild conditions on range-space steps and approximate Hessians, without assuming any regularity, it is proved that either every limit point of the iterate sequence is a Karush-Kuhn-Tucker point of the barrier subproblem and the penalty parameter remains bounded, or there exists a limit point that is either an infeasible stationary point of minimizing the ℓ norm of violations of constraints of the original problem, or a Fritz-John point of the original problem. In addition, we analyze the local convergence properties of the algorithm, and prove that by suitably controlling the exactness of range-space steps and selecting the barrier parameter and Hessian approximation, the algorithm generates a superlinearly or quadratically convergent step. The conditions on guaranteeing that all slack variables are still positive for a full step are presented. [ABSTRACT FROM AUTHOR]

The relationship between the mathematical program with linear complementarity constraints (MPLCC) and its inequality relaxation is studied. Based on this relationship, a new sequential quadratic programming (SQP) method is presented for solving the MPLCC. A certain SQP technique is introduced to deal with the possible infeasibility of quadratic programming subproblems. Global convergence results are derived without assuming the linear independence constraint qualification for MPEC, the nondegeneracy condition, and any feasibility condition of the quadratic programming subproblems. Preliminary numerical results are reported. [ABSTRACT FROM AUTHOR]

Generalized stationary points of the mathematical program with equilibrium constraints (MPEC) are studied to better describe the limit points produced by interior point methods for MPEC. A primal-dual interior-point method is then proposed, which solves a sequence of relaxed barrier problems derived from MPEC. Global convergence results are deduced under fairly general conditions other than strict complementarity or the linear independence constraint qualification for MPEC (MPEC-LICQ). It is shown that every limit point of the generated sequence is a strong stationary point of MPEC if the penalty parameter of the merit function is bounded. Otherwise, a point with certain stationarity can be obtained. Preliminary numerical results are reported, which include a case analyzed by Leyffer for which the penalty interior-point algorithm failed to find a stationary point. [ABSTRACT FROM AUTHOR]

We present a primal-dual interior-point algorithm for solving optimization problems with nonlinear inequality constraints. The algorithm has some of the theoretical properties of trust region methods, but works entirely by line search. Global convergence properties are derived without assuming regularity conditions. The penalty parameter ρ in the merit function is updated adaptively and plays two roles in the algorithm. First, it guarantees that the search directions are descent directions of the updated merit function. Second, it helps to determine a suitable search direction in a decomposed SQP step. It is shown that if ρ is bounded for each barrier parameter μ, then every limit point of the sequence generated by the algorithm is a Karush -- Kuhn -- Tucker point, whereas if ρ is unbounded for some μ, then the sequence has a limit point which is either a Fritz -- John point or a stationary point of a function measuring the violation of the constraints. Numerical results confirm that the algorithm produces the correct results for some hard problems, including the example provided by Wächter and Biegler, for which many of the existing line search--based interior-point methods have failed to find the right answers. [ABSTRACT FROM AUTHOR]

Multistage stochastic linear programming (MSLP) is a powerful tool for making decisions under uncertainty. A deterministic equivalent problem of MSLP is a large-scale linear program with nonanticipativity constraints. Recently developed infeasible interior point methods are used to solve the resulting linear program. Technical problems arising from this approach include rank reduction and computation of search directions. The sparsity of the nonanticipativity constraints and the special structure of the problem are exploited by the interior point method. Preliminary numerical results are reported. The study shows that, by combining the infeasible interior point methods and specific decomposition techniques, it is possible to greatly improve the computability of multistage stochastic linear programs. [ABSTRACT FROM AUTHOR]

Electronic synapses with both long-term and short-term plasticity are considered as significant components for constructing brain-inspired computing systems. Research progress on electrical synapses have proved that memristors possess huge similarities with biological synapses. Nevertheless, an effective mean of manipulating the biological properties of memristors is still unclear. In this letter, we propose a memristor and reveal that the compliance current of electroforming plays an active role in tuning short-term and long-term plasticity of the memristors. The results may provide a useful guideline for manipulating memristor as electronic synapses in the hardware implementation of artificial neural networks. [ABSTRACT FROM AUTHOR]

A novel structure design of a surface acoustic wave (SAW) micro-optic-electro-mechanical-system (MOEMS) strain sensor with a light readout unit is presented in this paper. By measuring the polarization intensity ratio of the TE/TM mode outputted from the waveguide, the strain produced from an object can be measured precisely. The basic working principle of the SAW MOEMS strain sensor is introduced and the mathematical model of the strain sensor system is established. The SAW characteristics effected by the strain sensor are mathematically deduced. The coupling coefficient between the SAW modes and light modes can be calculated based on the theory of coupling modes. The conversion coefficient of polarized light modes is obtained. Due to the restrictions of the specific parameters of the device, the level of technology and the material characteristics, the sensitivity of the strain sensor system is calculated through simulation as 0.1 με, with a dynamic range of 0 ~ ±50 με. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of baicalin on the proliferation of extranodal NK/T-cell lymphoma cells and the sensitivity of the cells to the drug. Methods: Cell-counting-kit (CCK) assay was used to determine cell activity, while the antagonistic, superimposed and synergistic effects of drug combinations were investigated by coefficient of drug interaction (CDI). Cell proliferation was assessed using 5-ethynyl-2’- deoxyuridine (EdU) test. Flow cytometry was carried out to determine the apoptosis of studied extranodal NK/T-cell lymphoma cells. Furthermore, western-blot was used to evaluate the expression levels of BCL2, BAX, cleaved-caspase3 and caspase3 of the cells. Results: Survival of SNK-6 and YTS cells decreased gradually in a concentration-dependent manner (r = -0.97 and -0.98). Cell viability at the same concentration diminished with time, but with increase in cisplatin concentration, cell viability at the same time point also decreased. At cisplatin concentrations of 5, 10, and 20 μmol/L, reduction in cell viability between the two groups were significantly different (p < 0.001). Furthermore, the proliferation of SNK-6 and YTS cells decreased with increasing baicalin concentrations while apoptosis of the cells increased with increasing baicalin concentration. Conclusion: Baicalin inhibits the proliferation but promotes the apoptosis of SNK-6 and YTS cells. Cisplatin plus baicalin lowers cell proliferation rate and increase the apoptosis rate of both SNK-6 and YTS cells compared with baicalin or cisplatin alone. This drug combination should be further explored for its apoptosis potential in animal models. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the efficacy of arthroscopic internal drainage (AID) and cyst wall resection (CWR) in children with popliteal cysts., Methods: This study included 16 pediatric patients with popliteal cysts and received arthroscopy using the double posteromedial (PM) portal system during June 2020 and June 2021 at The General Hospital of Northern Theater Command. Among these pediatric patients, 14 were males and two were females, with the mean age of nine years (range: 7-12 years). The left knee was affected in 12 cases, while the right knee was involved in the rest four cases. All patients underwent MR imaging before the procedure to assess whether there was intra-articular trauma and whether the popliteal cyst communicated with the knee-joint cavity. The MRI results showed that each patient had a simple popliteal cyst that involved a single knee joint without intra-articular trauma, which was classified as Grade-1 (n=3), Grade-2 (n =10) or Grade-3 (n =3) according to the Rauschning and Lindgren grading of knee joint symptoms. Arthroscopy was performed through anterolateral (AL) and PM portals to the knee joint for AID plus CWR, and the surgical outcomes were evaluated based on the Rauschning and Lindgren criteria., Results: No major vascular or nerve injury occurred during the operation. Postoperative complications such as wound infection and lower-extremity deep venous thrombosis were not recorded in these patients. Complications involving the saphenous nerve or the great saphenous vein or pseudocyst formation were not observed during the follow-up period. All patients completed the follow-up ranging from 3-12 months and were identified to have grade-0 (n=15) and grade-1 (n=1) popliteal cysts based on the Rauschning and Lindgren criteria, indicating significant improvement compared with the preoperative levels (all p<0.05). Moreover, no recurrence was recorded after operation., Conclusion: AID plus CWR is a minimally invasive and safe approach for pediatric patients with popliteal cysts to promote postoperative recovery and reduce the recurrence rate., Competing Interests: Conflicts of interest: None., (Copyright: © Pakistan Journal of Medical Sciences.)

Objectives: To investigate the clinical efficacy of exposure enhancement technique and femoral condyle pushing technique applying in the posterior horn of the medial meniscus of the knee., Methods: From January 2016 to June 2019, 52 patients with injury in the medial meniscus treated in our department were selected. The horizontal tear of the posterior horn of the medial meniscus was repaired by exposure enhancement technique and femoral condyle pushing technique using the meniscus suture system. Postoperatively, the efficacy was evaluated using the Lysholm scoring system., Results: These 52 patients were all followed up for 3~18 months, with an average of 12.5 ± 7.3 months. The pain and activity of all patients were significantly improved compared with those before surgery., Conclusion: Exposure enhancement technique and femoral condyle pushing technique in the repair of the posterior horn of the medial meniscus presents satisfactory efficacy. It can improve the pain and activity of the knee, and enhance the stability of residual meniscus. Therefore, it is worth promoting., Competing Interests: Conflicts of interest: None., (Copyright: © Pakistan Journal of Medical Sciences.)

Objective: To explore the clinical effects upon gap nonunion of antibiotic-loaded bone cement spacer combined with membrane induction on infected bone defects., Methods: The data of 16 patients with infected bone defects admitted in General Hospital of Shenyang Military Area Command from January 2009 to January 2011 were analyzed retrospectively. There were 12 males and 4 females aged between 24-63 years age (average 43.1 ± 9.7) who had received antibiotic laiden bone cement spacer treatment. Stage-1, debridement and anti-biotic treatment with intraoperative preparation of customized bone cement spacers (antibiotics and bone cement spacer) with or without internal or external fixation Stage-2, removal of spacer and repair of bone defects using membrane-induced technique and internal fixation at bone defects site., Results: Sixteen patients were followed up for 39-98 months, (67.2 ± 20.4) on average. All patients with infected bone defects were healed. X-ray showed that fractures had healed and the new bone formed at graft site was more radio opaque than that of adjacent bone segments. The healing time was 6 to 10 months, (7.4 ± 1.1) on average. There was no recurrence of infection or deformity., Conclusion: The antibiotic-loaded cement spacer can control the local infection while maintaining the limb length and increasing the stability, reducing the contracture of bone and soft tissue, creating conditions for subsequent repair and reducing the infection rate of bone defects., Competing Interests: Conflicts of interest: None.

Objective: This study aimed to evaluate the expressions and clinical significance of bone Gla-protein (BGP), bone alkaline phosphatase (B-ALP) and C-terminal telopeptide of type I collagen (CTX) in patients with osteoporosis (OP), and to provide evidence for developing individualized treatment plans., Methods: Seventy-two OP patients in our hospital were selected as an OP group, and another 72 healthy subjects were used as a control group. Their BGP, B-ALP and CTX levels as well as bone mineral density (BMD) values were measured. The correlations between BGP, B-ALP and CTX levels and BMD values were determined., Results: The BGP level of the OP group [(5.61±5.52) ng/ml] was significantly higher than that of the control group (P<0.05), but the levels of B-ALP and CTX did not differ significantly (P>0.05). The BMD values of femoral neck and Ward's triangle in the OP group were negatively correlated with the B-ALP levels (P<0.05). For women OP patients, the BMD values of femoral neck and Ward's triangle were also negatively correlated with the B-ALP levels (P<0.05). The BMD of femoral neck in the control group was negatively correlated with the CTX level (P<0.05)., Conclusion: Determining BGP, B-ALP and CTX levels can evaluate the bone metabolism degree, which provides evidence for clinical typing of OP and developing treatment strategies.