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We prove new $$L^p$$ -estimates with $$1

Let M(2,1)(N) be the infimum of the largest sum-free subset of any set of N positive integers. An old conjecture in additive combinatorics asserts that there is a constant c = c(2, 1) and a function ω(N) → ∞ as N → ∞, such that cN + ω(N) < M(2,1)(N) < (c + o(1))N. The constant c(2, 1) is determined by Eberhard, Green, and Manners, while the existence of ω(N) is still wide open. In this paper, we study the analogous conjecture on (k,ℓ)-sum-free sets and restricted (k,ℓ)-sum-free sets. We determine the constant c(k,ℓ) for every (k,ℓ)-sum-free sets, and confirm the conjecture for infinitely many (k,ℓ).

We improve local smoothing estimates for fractional Schrödinger equations for $α\in (0,1) \cup (1,\infty)$., 28 pages, small corrections following referee report

In this paper, we present a tracking and control system used to auto-aiming and shooting some given targets. By combining the traditional computer vision method and the neutral network method, our detection for some specific objects achieves real-time (100fps+) and it is robust enough to work on most normal situations. To achieve better performance in shooting moving targets, we fuse the IMU data to do the motion prediction. This makes the system outperforms the human players in hit rate. This system is applied for the RoboMaster competition as an aim-support system and shows good results.

There are two parts for this paper. In the first part, we extend some results in a recent paper by Du, Guth, Li and Zhang to a more general class of phase functions. The main methods are Bourgain-Demeter's $l^2$ decoupling theorem and induction on scales. In the second part, we prove some positive results for the maximal extension operator for hypersurfaces with positive principal curvatures. The main methods are sharp $L^2$ estimates by Du and Zhang, and the bilinear method by Wolff and Tao., 24 pages, revised version incorporating referees' suggestions

Although cloud computing has some eminent advantages such as low cost, resource elasticity, yet the highly dynamic, distributed and opaque nature of cloud services makes it a meaningful challenge to establish and manage trust between cloud service providers and consumers. Based on this background, this paper first describes the common concepts and classifications of trust issues and trust models, then generalize trust issues in cloud computing based on the research of existing work, next enumerates typical trust evaluation models from several different perspectives in cloud computing. Finally, conclusions including several potential trends are proposed for the future work.

Background: Diabetic nephropathy (DN) is a major cause of chronic kidney disease around the world. Endoplasmic reticulum (ER) stress plays an important role in DN progression. Ligustrazine (Lig) is derived from the Chinese herb Ligusticum wallichii and is reported to exert anti-oxidant, anti-inflammation and anti-fibrosis effects. The aim of our study was to investigate the influence of Lig on the treatment of DN. Methods: Streptozotocin (STZ) was used to induce diabetes in Sprague–Dawley (SD) rats. Then, STZ-induced rats were treated with different concentrations of Lig (50 or 150 mg kg−1 day−1) for 8 weeks of treatment. Urinary albumin concentrations, blood urea nitrogen (BUN), serum creatinine (Scr) and creatinine clearance (Ccr) were determined. The levels of proinflammatory cytokines (IL-8, IL-6, IL-1β and TNF-α) were estimated by ELISA. TUNEL assay was used for apoptosis index measurement. Western blot was used for the detection of GRP78, CHOP, p-eIF2α, eIF2α, p-p38, p-38, p-ERK1/2 and ERK1/2. Results: Lig treatment significantly reduced urinary albumin excretion, BUN and Scr and increased Ccr in STZ-induced rats. Lig also suppressed the levels of IL-8, IL-6, IL-1β and TNF-α and inhibited apoptosis dose-dependently. In addition, Lig inhibited GRP78 and CHOP expression and prevented the phosphorylation of eIF2α, p-38 and ERK1/2. Conclusion: Our study indicated that Lig attenuated renal damage by inhibiting ER stress in DN by inactivating MAPK pathways.

Micro-EDM milling is an effective machining process for three-dimension micro-cavity of high hardness materials. Fix-length compensation method is an efficient compensation method for cavity milling by improving single layer thickness. A truncated cone shaped end is formed under fix-length compensation method by using tubular electrode. This paper presents the compensation steps with tubular electrodes. According to the start hole drilling process, the geometrical model of the tubular electrode at the start point was established, and the compensation algorithm was given. Geometrical model for the ending part of the closed milling path was presented and the compensation algorithm was deduced. Two typical closed milling paths, square and circular paths, were manufactured based on the proposed compensation algorithms. Experimental results show that these two algorithms work well. The relative dimensional error is within 1.2%, and surface fluctuation is within 2.5 μm.

The road edge detection method, proposed by us, highlights the morphological and color features of the road in the image. The method performs color space conversion and color feature screening on color images containing road information, and Canny operator is used for edge detection. Then the edge detection results are detected by straight lines, and the road edges are detected and marked based on the principle of Hough transform. The experiment of edge detection on road pictures with complex background proves that the detection method can better detect the road edge. The novelty of this method is to combine several principles such as color feature screening, Canny operator and Hough transform. Therefore, a new method of road edge detection is formed.

In this paper, binarization and closed operation are used to improve traditional sharpening algorithms. Aiming at the problem that traditional sharpening algorithm tends to sharpen noise when processing pictures. First of all, this paper eliminates noise through binarization, and then uses morphological closed operation to fill the cavities generated by noise. Finally, the Sobel operator is used to detect the edge of the image, which is superimposed with the original image and simulated on matlab. The simulation result shows that the improved sharpening algorithm based on binarization and closed operation can not only sharpen the edges of the image, but also not sharpen the noise. The innovation of this paper is to make the image sharpening effect better than traditional phase algorithm.

Aims: To analyze the relationship between oral active vitamin D treatment and mortality in maintenance hemodialysis (MHD) patients. Methods: We examined the association of oral calcitriol treatment with mortality in 156 MHD patients (80 men and 76 women; mean age: 59 w 15 years). The survival analysis of all-cause and cardiovascular mortality was performed using the Kaplan-Meier survival and Cox proportional-hazards analyses. Results: In all, 108 of the 156 patients received active vitamin D treatment. The intact parathyroid hormone level was obviously lower in the patients who received active vitamin D treatment than in those who did not. Throughout the whole follow-up, overall mortality was 16.7% (26 deaths, 13 in each group). The cardiovascular mortality rates were 14.6% (8/48) in the control group and 4.6% (5/108) in the calcitriol group. The crude analysis of all-cause and cardiovascular mortality using the Kaplan-Meier curve showed a significant reduction in mortality risk for patients who received oral active vitamin D compared with those who did not receive it (p = 0.015 and 0.026, respectively). Cox's regression analysis showed that active vitamin D treatment was associated with a significantly lower risk of all-cause mortality (RR = 0.399, 95% CI 0.185-0.862, p = 0.019) and cardiovascular mortality (RR = 0.295, 95% CI 0.094-0.93, p = 0.037). However, after adjusting for potential confounding variables, oral active vitamin D therapy was no longer clearly associated with a lower risk of either all-cause or cardiovascular mortality. Conclusion: Oral active vitamin D treatment was associated with improved survival in MHD patients. However, this survival benefit was smaller than previously reported, and a large cohort study should be performed. i 2014 S. Karger AG, Basel

Glucocorticoid treatment is the first choice therapy for adults with minimal change nephrotic syndrome; however, this therapy associates with many adverse effects. Tacrolimus may be an alternative to conventional glucocorticoid therapy. To investigate this possibility, we conducted a prospective, randomized, controlled trial (WHO International Clinical Trials Registry Platform: ChiCTR-TRC-11001454) in eight renal units across China. We randomized enrolled patients with adult-onset minimal change nephrotic syndrome (n=119) to receive glucocorticoid therapy or tacrolimus after intravenous methylprednisolone (0.8 mg/kg per day) for 10 days. Patients received a conventional glucocorticoid regimen or tacrolimus monotherapy, starting with 0.05 mg/kg per day (target trough whole-blood level of 4-8 ng/ml) for 16-20 weeks and subsequently tapering over approximately 18 weeks. Remission occurred in 51 of 53 (96.2%; all complete remission) glucocorticoid-treated patients and 55 of 56 (98.3%; 52 complete and three partial remission) tacrolimus-treated patients (P=0.61 for remission; P=0.68 for complete remission). The groups had similar mean time to remission (P=0.55). Relapse occurred in 49.0% and 45.5% of the glucocorticoid- and tacrolimus-treated patients, respectively (P=0.71), with similar time to relapse (P=0.86). Seven (13.7%) glucocorticoid-treated and four (7.3%) tacrolimus-treated patients suffered frequent relapse (P=0.28); five glucocorticoid-treated and two tacrolimus-treated patients became drug dependent (P=0.26). Adverse events occurred more frequently in the glucocorticoid group (128 versus 81 in the tacrolimus group). Seven adverse events in the glucocorticoid group and two adverse events in the tacrolimus group were serious. Consequently, tacrolimus monotherapy after short-term intravenous methylprednisolone is noninferior to conventional glucocorticoid treatment for adult-onset minimal change nephrotic syndrome in this cohort.

Is corporate governance effective during the early stages of transition from central planning to market? If so, is the effectiveness due to the newly instituted reforms, or the remnants of the previous institutional regime? This study addresses these questions by drawing on agency theory and neo-institutional theory to examine the effectiveness of corporate governance during transition in the largest of the transition economies, the People's Republic of China. We choose a period of institutional upheaval—1998–2003—and test competing hypotheses with a sample of 416 publicly listed firms. We find strong evidence that poor-performing CEOs are more likely to leave or be dismissed which suggests that China's corporate governance was effective during this time period. However, the results also suggest that the effectiveness was likely due more to the remnants of the previous institutional regime than to the newly implemented Anglo-American style governance structures.

This chapter examines empirically the effectiveness of the ownership structure, board structure, and compensation of a sample of Chinese firms over the period from 1997 to 1999. We find that ownership concentration and percentage of employees’ shareholding have positive impacts on firm performance, but the percentage of major officers ’ shareholding does not. The ratio of insider directors is not related to firm performance either. CEO duality has an impact on chairmen’s salaries. However, managerial compensation is, in general, not related to firm performance. Overall, there is only weak evidence supporting the effectiveness of Chinese firms’ internal governance mechanisms.