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More than half of the carbon pools in peatlands are stored in the soil layers below 30 cm, yet little is known about the carbon stabilizing factors at these depths. Although iron oxide minerals are considered to be important for stabilizing organic carbon (OC), their role in the preservation of OC in peatlands, especially in the deep layers, is poorly understood. Here, we collected 1 m soil profiles from six peatlands in Central and West China to quantitatively study the vertical distribution characteristics of iron-bound OC (Fe-bound OC), and the influencing physicochemical properties of the soil. The results showed that the content of reactive iron (FeR) was enriched in the top layer and decreased gradually with depth. While Fe-bound OC was positively correlated with FeR, its concentration did not decrease with depth in the peat profile. There were no obvious trends in the distributions of FeR and Fe-bound OC with water level fluctuations in the peat profile. In addition, the proportion of Fe-bound OC to soil organic carbon in the deep peat (31 to 100 cm) was equivalent to that in the surface peat (0 to 30 cm), indicating that iron oxide mineral provides comparable protection of OC in both layers. According to upper estimates of global peatland carbon storage (612 Pg), it could be predicted that 23.81 ± 11.75 Pg of OC is protected by association with FeR. These results indicated that iron oxide minerals are the effective "rusty sink" of OC sequestration in peatland, and a key factor for its long-term preservation. The results from this study make a valuable contribution to the carbon dynamics knowledgebase for peatlands, and provide a basis for improved predictive simulations. [ABSTRACT FROM AUTHOR]

The article discusses Transforming growth factor is well known to restrain cytotoxic T cell responses to maintain self-tolerance and to promote tumor immune evasion. In this study, we have investigated the role of SMAD4, a core component in the TGF signaling pathway, in CD8+ T cells. Unexpectedly, we found that SMAD4 was critical in promoting CD8+ T cell function in both tumor and infection models.

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. [ABSTRACT FROM AUTHOR]

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. [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]

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]

We present a sequential quadratic programming method without using a penalty function or a filter for solving nonlinear equality constrained optimization. Ill each iteration, the linearized constraints of the quadratic programming are relaxed to satisfy two mild conditions; the step-size is selected such that either the value of the objective function or the measure of the constraint violations is sufficiently reduced. As a result, our method has two nice properties. First, we do not need to assume the boundedness of the iterative sequence. Second, we do not need any restoration phase which is necessary for filter methods. We prove that the algorithm will terminate at either an approximate Karush-Kuhn-Tucker point, an approximate Fritz-John point, or an approximate infeasible stationary point which is an approximate stationary point for minimizing the l2 norm of the constraint violations. By controlling the exactness of the linearized constraints and introducing a second-order correction technique, without requiring linear independence constraint qualification, the algorithm is shown to be locally superlinearly convergent. The preliminary numerical results show that the algorithm is robust and efficient when solving some small- and medium-sized problems from the CUTE collection. [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]

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]

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]

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]

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. [ABSTRACT FROM AUTHOR]

Objectives: Pyroptosis has been found implicated in several diseases, however, whether it was involved in gouty arthritis remained unclear. Our study was performed to uncover the role of pyroptosis in gouty arthritis based on a mice model. Methods: Mouse gouty arthritis model was established by injections of potassium oxonate (PO), monosodium urate (MSU) and pyroptosis suppressor disulfiram. The diameter of the ankle joints was measured, and ankle joints morphology was observed with hematoxylin-eosin (H&E) staining. Uric acid, creatinine and blood urea nitrogen (BUN) concentrations were measured, while cytokines level and xanthine oxidase (XOD) activity were quantified. Relative pyroptosis markers expressions were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot as needed. Results: In mouse model, PO and MSU injections cause damage to right ankle, increase the root thickness ratio and uric acid, creatinine and BUN levels in serum and decrease the uric acid and creatinine levels in urine. Also, under PO and MSU treatment, up-regulated XOD activity, inflammatory cytokines levels and pyroptosis markers expressions are observed. Negative regulation of mice injury by disulfiram treatment is also observed. Conclusion: Pyroptosis inhibition might alleviate PO- and MSU-induced gouty arthritis, providing possible therapeutic strategies for gouty arthritis. [ABSTRACT FROM AUTHOR]

The spontaneous polarization (SP) and piezoelectric (PZ) constants of BxAl1-xN and BxGa1-xN (0≤x≤1) ternary alloys were calculated with the hexagonal structure as reference. The SP constants show moderate nonlinearity due to the volume deformation and the dipole moment difference between the hexagonal and wurtzite structures. The PZ constants exhibit significant bowing because of the large lattice difference between binary alloys. Furthermore, the PZ constants of BxAl1-xN and BxGa1-xN become zero at boron compositions of ~87% and ~74%, respectively, indicating nonpiezoelectricity. The large range of SP and PZ constants of BxAl1-xN (BAlN) and BxGa1-xN (BGaN) can be beneficial for the compound semiconductor device development. For instance, zero heterointerface polarization ΔP can be formed for BAlN and BGaN based heterojunctions with proper B compositions, potentially eliminating the quantum-confined Stark effect for c-plane optical devices and thus removing the need of non-polar layers and substrates. Besides, large heterointerface polarization ΔP is available that is desirable for electronic devices. [ABSTRACT FROM AUTHOR]

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]

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]

The article discusses a research study which aimed to evaluate the reliability and validity of the adapted simplified Chinese Functional Rating Index (SC-FRI) for patients with low back pain (LBP). An overview on the prevalence of low back pain is provided along with FRI. Methods are explained particularly the translation and cross-cultural adaptation of the original FRI into simplified Chinese. Results are presented in terms of cross-cultural adaptation, acceptability and internal consistency.

The article discusses the effect of tracheal/esophageal traction exercise (TTE) treatment on postoperative dysphagia after a cervical spine surgery. As defined, dysphagia is a postoperative complication of anterior cervical spine surgery. The study was conducted using TTE treatment prior to surgery in which the results were compared to that of the nontreated group. It was concluded that dysphagia may be reduced in patients by providing preoperative TTE treatment.

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]