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Endocan, a pro-inflammatory cytokine and pro-angiogenic factor, is a marker of endothelial dysfunction and has been proven to correlate with cardiovascular disease. In hemodialysis (HD) patients, cardiovascular disease is the major cause of mortality. Our study aimed to investigate the relationship between serum endocan and all causes of mortality in HD patients. A total of 103 patients, aged over 20 years old and undergoing HD for more than 3 months, were included and followed for 36 months. Mortality events, serum endocan, biochemical data, body mass index, systolic and diastolic blood pressure, baseline characteristics, and the use of antihypertensive and lipid-lowering drugs were recorded. In our study, a total of 26 deaths (25.2%) occurred. Hemodialysis patients with diabetes mellitus, older age, higher serum endocan, and lower creatinine and albumin levels had a higher risk of mortality. Adjusting for prognostic variables, HD patients with higher serum endocan (p = 0.010) and lower serum creatinine (p = 0.034) demonstrated significantly higher all-cause mortality. In our study, increased endocan and lower creatinine are associated with all-cause mortality in HD patients. Serum endocan levels could serve as a biomarker for a high mortality risk in HD patients. [ABSTRACT FROM AUTHOR]

Machinery can suffer from mechanical vibrations since resonance may be generated from time-varying external excitations under different operation conditions. These detrimental vibrations may significantly influence the device's performance, effectiveness and reliability in operation. In this paper, an innovative, simple and high-efficiency tuned vibration absorber (TVA) consisting of shape memory alloy (SMA) wires, which is referred to a wire-type tuned vibration absorber (WTVA), is proposed to reduce the induced vibration. Experiments are carried out using a six-degree-of-freedom platform which is designed to simulate the frame of precision machinery in practical applications. With the equivalent stiffness of SMA wires adjusted by the controlled electric current, the frequency tunability of WTVA can be achieved. When the natural frequency of WTVA tuned in with the disturbance frequency, the experimental results demonstrate that the efficiency in vibration reduction of the platform is drastically increased even with considerable weight difference between WTVA and the platform. Moreover, the tunable frequency span also increases greatly due to the new design of WTVA and the material characteristics of SMA wires.

In this study, the threshold voltage (VT) degradation mechanism for a hot electron stress (HES) under semi-ON state conditions in AlGaN/GaN high electron mobility transistors is analyzed. The drain current versus gate voltage (ID–VG) characteristic curves indicate that VT shifts in the positive direction after the stress. However, an abnormal phenomenon that VT continuously shifts in the positive direction even after recovery is observed. A result comparison of a negative bias stress (NBS) experiment indicates that a hole recombination in pre-existing buffer defects is crucial. Therefore, a complete model of VT degradation mechanism is proposed. Moreover, the proposed model is confirmed through an illumination experiment and a Silvaco simulation. [ABSTRACT FROM AUTHOR]

In the field of environmental education, it is crucial to obtain a profound understanding of students' learning about ecosystem concepts, particularly with regard to the intricate processes of material cycling. Material cycling involves the movement and transformation of elements and compounds within ecosystems and serves as a cornerstone for effective instructional techniques aimed at improving learning outcomes. This study examines the synergistic potential of merging inquiry-based instruction with information literacy within the context of the "mini ecosystem" theme to increase seventh-grade students' comprehension of ecosystem concepts, material cycling, modeling design, and visual literacy. Utilizing a quasiexperimental design, the student cohort was divided into an experimental group that was exposed to inquiry-based instruction and information literacy and a control group that utilized integrated audiovisual media. Assessment tools included standardized tests, open-ended inquiries, design drawings, and evaluations of visual literacy. This study sheds light on students' comprehension of concepts related to ecosystems and material cycling and highlights the effectiveness of integrating inquiry-based instruction and information literacy. Notably, the experimental group surpassed the control group in several aspects, including understanding and higher-order thinking of ecosystem concepts, overall model design with material selection, and overall visual literacy, including aesthetic techniques and creative imagination. However, no significant differences were found in conceptual design or material cycling of model design or in theme composition in visual literacy. In both groups, students with higher pretest scores did not exhibit improvement in the understanding of ecosystem concepts. Despite the identified limitations, the results underscore the potential benefits of each individual component (i.e., inquiry-based instruction and information literacy) as well as their combined synergistic effect in bolstering students' grasp of ecosystem concepts. The study concludes by discussing its limitations and providing suggestions for future research. • Examine impact of integrating 5E inquiry with information literacy into ecosystem understanding. • Analyze grasp of ecosystem and material cycling, modeling design, and visual literacy. • Experimental group outperformed control group in various ecosystem concepts. • Low-scoring students notably improve in the ecosystem and material cycling concepts. [ABSTRACT FROM AUTHOR]

The swine wastewater has the characteristics of high concentration of organic matter, suspended solids and more high ammonia nitrogen, odor, complex pollution ingredient and large emissions. Microbial fuel cells (MFC) is an electrochemical and biological systems related to chemical energy into electrical energy. A two-chambered cubic microbial fuel cell was used to evaluate the effect of a novel 3D electrode which made of iron and copper on the electricity generation. The swine wastewater containing total chemical oxygen demand (TCOD) 3300±300 mg/L was used as the feedstock in anode chamber, and the potassium ferricyanide was used as electron acceptor in cathode chamber. The MFC reactor was incubated with the initial pH 7.0 in a air-shaker with a temperature (ca. 35°C) and 100 rpm in fed-batch mode. A fixed external resistance (R) of 100 Ω was connected between the electrodes and the closed circuit potentials of the MFCs were recorded every 2 min. The results show that using iron 3D electrode has the peak electricity generation of 176 mV at the first two day and maintained the stable electricity voltage of 110 mV during the 5th to 15th days. The COD removal efficiency could reach 80%. Using copper 3D electrode only can generate the peak electricity of 33.1 mV and stable electricity of 27 mV with the COD removal efficiency of 70%.