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We first propose a new error bound for the linear complementarity problems when the involved matrices are generalized Nekrasov matrices, which generalizes the recent result obtained by Li et al. (Numer. Algorithms 74:997–1009, 2017). Then we present two new error bounds for the linear complementarity problems when the involved matrices are Nekrasov matrices. Numerical examples are given to illustrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative bone disease associated with aging. The rising global aging population has led to a surge in OA cases, thereby imposing a significant socioeconomic burden. Researchers have been keenly investigating the mechanisms underlying OA. Previous studies have suggested that the disease starts with synovial inflammation and hyperplasia, advancing toward cartilage degradation. Ultimately, subchondral-bone collapse, sclerosis, and osteophyte formation occur. This progression is deemed as "top to bottom." However, recent research is challenging this perspective by indicating that initial changes occur in subchondral bone, precipitating cartilage breakdown. In this review, we elucidate the epidemiology of OA and present an in-depth overview of the subchondral bone's physiological state, functions, and the varied pathological shifts during OA progression. We also introduce the role of multifunctional signal pathways (including osteoprotegerin (OPG)/receptor activator of nuclear factor-kappa B ligand (RANKL)/receptor activator of nuclear factor-kappa B (RANK), and chemokine (CXC motif) ligand 12 (CXCL12)/CXC motif chemokine receptor 4 (CXCR4)) in the pathology of subchondral bone and their role in the "bottom-up" progression of OA. Using vivid pattern maps and clinical images, this review highlights the crucial role of subchondral bone in driving OA progression, illuminating its interplay with the condition. [ABSTRACT FROM AUTHOR]

Purpose: Haptoglobin (Hp) is a hemoglobin-binding protein that functions as an antioxidant in human plasma. It is reported that glycemic variability (GV) plays a key role in diabetes-related complications associated with impaired glucose metabolism and oxidative stress. Here we aim to investigate whether the effect of GV on diabetic macroangiopathy depends on Hp genotype in type 2 diabetes. Methods: A number of 860 Chinese patients with type 2 diabetes was genotyped and assigned to two Hp subgroups (Hp 2-2 and Hp 1 carriers). Glycemic variability (GV) was assessed by using a retrospective continuous glucose monitoring system for three consecutive days, and it was measured using the glucose coefficient of variation (%CV), which is calculated as the ratio of glucose standard deviation to glucose mean. Clinical features, history of cardiac surgery, and vascular imaging tests were utilized to diagnose macroangiopathy. We evaluated the interaction between Hp genotypes and %CV on diabetic macroangiopathy. Furthermore, serum concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured using an enzyme-linked immunosorbent assay as a biomarker of oxidative stress. Results: Serum 8-OHdG levels were positively correlated with %CV in Hp 1 carriers (r = 0.117; p = 0.021). Patients in the highest %CV tertile were associated with a higher prevalence of diabetic macroangiopathy than those in the lowest %CV tertile in Hp 1 carriers (OR = 2.461 [95% CI, 1.183–5.121], p = 0.016), but not in those with Hp 2-2 genotype (OR = 0.540 [95% CI, 0.245–1.191], p = 0.127). A significant interactive effect of Hp genotypes and %CV on diabetic macroangiopathy was found (p interaction = 0.008). Conclusion: Hp genotype modifies the effect of GV on diabetic macroangiopathy among Chinese patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

The number of visible global navigation satellite system (GNSS) satellites is an important indicator for evaluating positioning accuracy. In urban areas, buildings and trees cause serious satellite signal obstruction and attenuation. Studies have used three-dimensional (3D) city models or 2D panoramic imagery to calculate the visibility of satellites in some areas at a certain time. However, the production of accurate 3D models involves heavy manual work and is expensive, while public panoramic imagery mainly spreads over roads and cannot support 3D analysis. Also, the existing studies seldom consider the impact of urban on satellite signals. We thus propose a method that considers the influence of both trees and buildings. A full-path propagation model for GNSS signals is established. Then, a fast visibility analysis of satellites using an airborne laser scanning point cloud is performed. Hence, the number of visible satellites at a specific time can be mapped. In addition, real-time and forecast visibility maps are generated according to the GNSS ephemeris. To verify the effectiveness of the proposed method, we collected field measurement data for qualitative and quantitative evaluation of experiments. The experiments demonstrated that the proposed method provides an easy-to-use and high-precision solution to map the spatio-temporal visibility of satellites in 3D urban space, which serves as an important reference for applications like unmanned aerial vehicles route planning. [ABSTRACT FROM AUTHOR]

Interdisciplinary research has attracted extensive attention from researchers and policymakers by its nature of integrating various types of knowledge from multiple disciplines to solve complex scientific problems. Besides the studies on citation-based interdisciplinary knowledge flow, recent efforts have been made to demystify the characteristics of knowledge integration in interdisciplinary research from a knowledge content perspective. To deeply understand the knowledge content integrated into interdisciplinary research, two tasks were formulated in this study. One was to identify the knowledge units integrated by an interdisciplinary field, which are defined as integrated knowledge phrases (IKPs) shared between citances and cited texts of the references. The other was to classify the identified IKPs into several knowledge categories, which could reflect their knowledge functions in the field. We proposed a methodology framework to automate the identification and classification of IKPs by using natural language processing techniques and deep learning models. This automatic methodology was tested on an eHealth dataset. The experiments showed that the baseline matching method and the word embedding based similarity matching method are effective for the identification task, and the Bidirectional Encoder Representation from Transformers (BERT) model using section titles and citances as input features achieved the best performance on the classification task, with an accuracy of 0.951. We further showcased the application of IKPs in the case study with expanded literature of eHealth. The two tasks were operated on the new dataset, then co-occurrence networks of IKPs were constructed and mapped to visualize the knowledge integration structure of the field. This study provides a feasible content-based methodology to foster the fine-grained understanding of the knowledge integration structure of an interdisciplinary field, which could become a general domain analysis method. [ABSTRACT FROM AUTHOR]

Geometric methods are important for researching the differential properties of metric projectors, sensitivity analysis, and the augmented Lagrangian algorithm. Sun [3] researched the relationship among the strong second-order sufficient condition, constraint nondegeneracy, B-subdifferential nonsingularity of the KKT system, and the strong regularity of KKT points in investigating nonlinear semidefinite programming problems. Geometric properties of cones are necessary in studying second-order sufficient condition and constraint nondegeneracy. In this paper, we study the geometric properties of a class of nonsymmetric cones, which is widely applied in optimization problems subjected to the epigraph of vector k-norm functions and low-rank-matrix approximations. We compute the polar, the tangent cone, the linear space of the tangent cone, the critical cone, and the affine hull of this critical cone. This paper will support future research into the sensitivity and algorithms of related optimization problems. [ABSTRACT FROM AUTHOR]

We aim to investigate the relationship between serum somatostatin (SST) levels and glucose-lipid metabolism at various stages of glucose tolerance in the Jino ethnic minority (n=111) and Han population (n=113) of Yunnan Province, southwest China. Anthropometric parameters and biochemical traits were measured. Serum SST and plasma glucagon levels were tested. Participants were divided into three subgroups: isolated fasting hyperglycemia (IFH), isolated post challenge hyperglycemia (IPH) and normal glucose tolerance (NGT). SST levels were found lower while glucagon levels were significantly higher in the Jino ethnic with IPH (P=0.0026 and P=0.0069, respectively). Fasting glucose and high density lipoprotein-cholesterol (HDL-C) levels were higher (P=0.0055 and P=0.0021, respectively) and fasting insulin levels and homeostasis model assessments β-cell function were lower (P=0.0479 and P=0.0007, respectively) in the Jino population. After adjusting for confounding factors, the serum SST level was associated with glucagon (P<0.0001) in both populations. The SST level was correlated with fasting Cpeptide (P=0.0267) in Jino and HDL-C levels in Han (P=0.0079). Our findings suggest that serum SST levels and plasma glucagon levels may vary in subjects with IPH between two ethnics. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: We aimed to evaluate the combined effects of type 2 diabetes risk variants on predicting deterioration of blood glucose and progression of beta cell function and insulin sensitivity in a 9 year prospective cohort from the Chinese population. Methods: We constructed a weighted genetic risk score (GRS) model based on 40 variants associated with type 2 diabetes validated in an established cross-sectional Chinese population ( n = 6,822). The weighted scores were categorised into tertiles to assess the predictive capacity for incidence of type 2 diabetes and impaired glucose regulation (IGR), as well as for changes in Stumvoll first- and second-phase insulin secretion indices and Gutt's insulin sensitivity index (ISI) in a community-based 9 year prospective cohort ( n = 2,495), including 2,192 individuals with normal glucose tolerance and 303 with IGR at baseline, through logistic, Cox and multiple linear regression tests. Results: Weighted GRS predicted the incidence of type 2 diabetes and IGR in logistic regression (OR 1.236, 95% CI 1.100, 1.389, p = 0.0004) as well as in the Cox model (HR 1.129, 95% CI 1.026, 1.242, p = 0.0128) after adjusting for age, sex, BMI, smoking and alcohol status at baseline. Moreover, we observed that weighted GRS was able to predict deterioration in beta cell function (β = −0.0480, p = 9.66 × 10 and β = −0.0303, p = 3.32 × 10 for first- and second-phase insulin secretion, respectively), but not insulin sensitivity ( p = 0.3815), during the 9 year follow-up period. Conclusions/interpretation: The weighted GRS predicted blood glucose deterioration arising from change in beta cell function in the Chinese population. Individuals in the intermediate- or high-weighted GRS group exhibited progressive deterioration of beta cell function. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: Three recent genome-wide association studies (GWAS) identified several single-nucleotide polymorphisms (SNPs) with modest effects on diabetic retinopathy in Mexican-American and white patients with diabetes. This study aimed to evaluate the effects of these variants on diabetic retinopathy in Chinese patients with type 2 diabetes. Methods: A total of 1,972 patients with type 2 diabetes were recruited to this study, including 819 patients with diabetic retinopathy and 1,153 patients with diabetes of ≥5 years duration but without retinopathy. Forty SNPs associated with diabetic retinopathy in three GWAS were genotyped. Fundus photography was performed to diagnose and classify diabetic retinopathy. Results: rs17684886 in ZNRF1 and rs599019 near COLEC12 were associated with diabetic retinopathy (OR 0.812, p = 0.0039 and OR 0.835, p = 0.0116, respectively) and with the severity of diabetic retinopathy ( p = 0.0365 and p = 0.0252, respectively, for trend analysis). Sub-analysis in patients with diabetic retinopathy revealed that rs6427247 near SCYL1BP1 (also known as GORAB) and rs899036 near API5 were associated with severe diabetic retinopathy (OR 1.368, p = 0.0333 and OR 0.340, p = 0.0005, respectively). The associations between rs6427247 and rs899036 and severe diabetic retinopathy became more evident after a meta-analysis of published GWAS data (OR 1.577, p = 2.01 × 10 for rs6427247; OR 0.330, p = 5.84 × 10 for rs899036). Conclusions/interpretation: We determined that rs17684886 and rs599019 are associated with diabetic retinopathy and that rs6427247 and rs899036 are associated with severe diabetic retinopathy in Chinese patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

The PSMD6 variant rs831571 has been identified as a susceptibility locus for type 2 diabetes mellitus (T2DM). This study aimed to investigate the association of this variant with therapeutic effects of oral antidiabetic drugs in Chinese T2DM patients. 209 newly diagnosed T2DM patients were randomly assigned to treatment with repaglinide or rosiglitazone for 48 weeks, and the therapeutic effects were compared. In the rosiglitazone cohort, rs831571 showed significant associations with fasting plasma glucose (FPG), 2-h glucose and decrement of glycated haemoglobin (HbA1c) levels after 24 weeks of treatment (P = 0.0368, 0.0468 and 0.0247, respectively). The C allele was significantly associated with a better attainment of FPG at 24 and 32 weeks (P = 0.0172 and 0.0257, respectively). Survival analyses showed CC homozygotes were more likely to attain a standard FPG level (P = 0.0654). In the repaglinide cohort, rs831571 was significantly associated with decreased HbA1c levels after 24 weeks of treatment, the homeostatic model assessment of insulin resistance and fasting insulin level after 48 weeks of treatment with repaglinide (P = 0.0096, 0235 and 0.0212, respectively). In conclusion, we observed that the PSMD6 variant rs831571 might be associated with the therapeutic effects of rosiglitazone and repaglinide in Chinese T2DM patients. However, these findings need to be confirmed in the future. [ABSTRACT FROM AUTHOR]