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Balanced clustering, which generates clusters of similar sizes, can be useful in a variety of applications. However, existing clustering algorithms either cannot guarantee balanced clustering results or require relatively high time complexities for balanced clustering. In this work, we propose a constrained balanced clustering method, which is referred to as τ-balanced clustering, to generate clusters with a controllable balance degree. The proposed method constrains the cluster sizes in the cluster assignment phase based on an established cluster bound size and an established bound for the number of largest clusters. Second, we optimize the basic τ-balanced clustering method by reducing some unnecessary calculations with two-level filtering. Third, we also design a parallel version for the basic τ-balanced clustering method and the optimized method on GPUs (Graphics Processing Units), to enhance the execution efficiency with high parallelism. Finally, we conduct a series of experiments on nine benchmark datasets to verify the proposed methods. The experimental results show that our methods successfully outperform the state-of-the-art methods.

Metabolic surgery is an effective treatment for type 2 diabetes mellitus (T2DM) in patients with obesity. However, the efficacy in patients with body mass index (BMI) < 32.5 kg/m2, especially in Asian populations, has not been widely reported, and there are few studies on the prediction of diabetes remission. We evaluated 112 patients with T2DM who underwent metabolic surgery between October 2008 and November 2019. The basic data of the patients were collected, and clinical variables were measured at 6 months, 1 year, and 2 years after metabolic surgery. Four independent predictors of surgical outcomes were identified to construct the prediction score. Diabetes remission occurred for 38 of the 112 patients. Ninety patients underwent Roux-en-Y gastric bypass, while the remaining 22 patients underwent sleeve gastrectomy. Weight, glucose, and lipid metabolism parameters were improved significantly after metabolic surgery. Age, BMI, insulin use, and duration were independent predictors of T2DM remission. The above four factors were defined with scores and developed ABID (age, BMI, insulin use, duration) scoring system. Patients with greater ABID scores had a greater probability of diabetes remission (from 0% at score 0 to 100% at score 4). The ABID score is a simple and easy-to-implement prediction score system of diabetes remission after metabolic surgery for T2DM patients with a BMI < 32.5 kg/m2.

A good combination of strength and fracture toughness is required for aerospace applications of laser additively manufactured (LAM) AerMet100 steel. To understand the role of microstructure in the combination of strength and fracture toughness of LAM AerMet100 steel, microstructures, fracture toughness properties and corresponding crack-tip fracture behaviors of the as-deposited specimen and five types of heat-treated specimens were mainly investigated. The results indicate the as-deposited microstructure of LAM AerMet100 steel with a high amount of retained austenite has a high KIC value of ~ 81.7 MPa m1/2. After a short process of cryogenic treatment and subsequent tempering treatment, the KIC value of the steel has the lowest value of ~ 60 MPa m1/2 due to the apparent decrease of austenite and weak cracking resistance, associating with intergranular cracking along the prior austenite columnar grain boundaries and transgranular cracking of intercellular regions. In contrast, the crack-tip fracture mode of the equiaxed-grain tempered martensite microstructure of LAM AerMet100 steel becomes completely transgranular cracking with the main mechanisms of micro-void nucleation and coalescence. Homogenization treatment can apparently decrease the amount and size of large-size alloy carbides and effectively improve the fracture toughness of the steel. Furthermore, proper microstructure modification (including control of large-size carbide, grain refinement and a decrease of retained austenite) by a longer treatment process can prompt tempered LAM AerMet100 steel to achieve a good combination of yield strength (~ 1827 MPa) and fracture toughness (~ 113 MPa m1/2) compared with the wrought one.

Information is scarce on the five-year effect of laparoscopic Roux-en-Y Gastric Bypass (LRYGB) on body composition for Type 2 diabetes mellitus (T2DM) patients with a low BMI. This study aimed to evaluate the five-year changes in body composition in a Chinese T2DM cohort with a BMI < 32.5 kg/m2 after LRYGB. Twenty-seven T2DM patients were assessed preoperatively (baseline) and 3 months, 6 months, 1 year, 3 years, and 5 years after LRYGB with dual-energy X-ray absorptiometry (DXA). DXA assessments were completed in 100%, 85%, 85%, 85%, 48%, and 37% at baseline and 3 months, 6 months, 1 year, 3 years, and 5 years, respectively. For the whole body, fat-free mass and muscle mass decreased from 6 months to 5 years after LRYGB (P < 0.05), while bone mineral content decreased at 5 years after LRYGB (P < 0.05). Fat mass of different regions decreased from 3 months to 1 year (P < 0.05), and a similar magnitude of variation was observed in body fat mass percentage. A fat redistribution characterized by the regional fat proportion of trunk and android decreasing and the regional fat proportion of limbs gaining (P < 0.05) occurred at 5 years after LRYGB. For low BMI patients with T2DM, LRYGB led to a short-term reduction in FM and a lasting reduction in FFM. A metabolically healthy fat redistribution occurring 5 years after LRYGB might be a promising mechanism to explain the lasting benefits of LRYGB for T2DM patients with a low BMI.

In our present study, we took advantage of the characteristics of RNA interference technology, which can efficiently, stably, and specifically silence target genes, and designed a small interfering RNA (siRNA) that could specifically target hTERT mRNA. We used a lentiviral vector (LV) to deliver the hTERT siRNA into telomerase-positive A549 lung cancer cells and investigated the effect of hTERT siRNA on the hTERT mRNA levels, hTERT protein levels, cell proliferation, and apoptosis in the lung cancer cells. The results from quantitative PCR, Western blotting, and the MTT assay showed that the expression levels of both hTERT mRNA and protein in the cells were significantly decreased and that the cell proliferation rate started to significantly slow down at 48 h after transfection with hTERT-LV. Our study demonstrated that siRNA sequences specifically targeting hTERT mRNA, which were packaged into lentivirus particles and then used to transfect the lung cancer cell line A549, can specifically silence the mRNA of the target gene, hTERT, and then reduce the hTERT protein expression level, which, in turn, reduces cell proliferation, inhibits cell growth, and induces apoptosis.