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Oral ascorbic acid 2-glucoside prevents coordination disorder induced via laser-induced shock waves in rat brain
摘要： Oxidative stress is considered to be involved in the pathogenesis of primary blast-related traumatic brain injury (bTBI). We evaluated the effects of ascorbic acid 2-glucoside (AA2G), a well-known antioxidant, to control oxidative stress in rat brain exposed to laser-induced shock waves (LISWs). The design consisted of a controlled animal study using male 10-week-old Sprague-Dawley rats. The study was conducted at the University research laboratory. Low-impulse (54 Pa?s) LISWs were transcranially applied to rat brain. Rats were randomized to control group (anesthesia and head shaving, n = 10), LISW group (anesthesia, head shaving and LISW application, n = 10) or LISW + post AA2G group (AA2G administration after LISW application, n = 10) in the first study. In another study, rats were randomized to control group (n = 10), LISW group (n = 10) or LISW + pre and post AA2G group (AA2G administration before and after LISW application, n = 10). The measured outcomes were as follows: (i) motor function assessed by accelerating rotarod test; (ii) levels of 8-hydroxy-2’-deoxyguanosine (8-OHdG), an oxidative stress marker; (iii) ascorbic acid in each group of rats. Ascorbic acid levels were significantly decreased and 8-OHdG levels were significantly increased in the cerebellum of the LISW group. Motor coordination disorder was also observed in the group. Prophylactic AA2G administration significantly increased the ascorbic acid levels, reduced oxidative stress and mitigated the motor dysfunction. In contrast, the effects of therapeutic AA2G administration alone were limited. The results suggest that the prophylactic administration of ascorbic acid can reduce shock wave-related oxidative stress and prevented motor dysfunction in rats.
关键词： ascorbic acid 2-glucoside,laser-induced shock waves,traumatic brain injury,Oxidative stress,motor dysfunction
更新于2025-09-23 15:21:01
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[IEEE 2020 11th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC) - Tehran, Iran (2020.2.4-2020.2.6)] 2020 11th Power Electronics, Drive Systems, and Technologies Conference (PEDSTC) - A New Non-isolated High Gain DC-DC Converter for Grid-Connected Photovoltaic Systems
摘要： a non-coupled high gain DC-DC converter is introduced in this article. It is based on ?uk converter, also consists of two inductors, which are charged in parallel by input source and discharged in series. The voltage gain of the proposed converter is improved, while it has no transformers and coupled inductors. Furthermore, the voltage stress across the switches is decreased. Hence, switches with lower voltage level can be used in the proposed converter. Fortunately, these switches have low ON-state resistance ((cid:1792)(cid:1804)(cid:1819).(cid:1815)(cid:1814) ), which causes decreasing in switch conduction losses. Furthermore, the proposed converter has high efficiency as well as simple control system. Finally, the principle operation and simulation results are presented.
关键词： high step-up gain,high efficiency,?uk-based converter,low voltage stress,non-isolated inductor
更新于2025-09-23 15:21:01
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Effect of supplementing blue/green LED to white LED light on broiler growth, stress and welfare
摘要： LED lighting provides an affordable lighting option for use in commercial poultry production. However, more information is needed to understand the effects of LED color on broiler welfare and growth. Five consecutive flocks (1 in summer, 1 in fall, 2 in winter, and 1 in spring) of straight run Ross 708 x Ross 708 broilers were reared in commercial type barns to 45 d. In treatment WO (white only), birds were reared under white LED only (Agrishift? MLB, Once Inc., Plymouth, MN). In treatment WS (white supplemented), birds were reared under white LED (Agrishift? MLB, Once Inc., Plymouth, MN) in the center aisle, with supplemental blue/green LED (Agrishift? MLBg, Once Inc., Plymouth, MN) above feed and water lines on either side of the barn. Each barn housed 26,200 chicks, and there were 2 barns in each treatment (n=52,400 per treatment). Treatments were rotated among barns between each flock. On d 45 blood samples were collected from 20 birds per barn (n=40/treatment) to assess plasma corticosterone (CORT) and heterophil/lymphocyte (H/L) ratio. On d 45, 100 birds/barn (n=200/treatment) were weighed individually and assigned scores for hock burn and foot pad dermatitis. All measures were affected by trial (P < 0.001). Plasma CORT and body weight were affected by the treatment*trial interaction (P ≤ 0.001). Overall, birds in the WS treatment had higher d 45 live body weight (P < 0.001) and lower hock burn scores (P = 0.032) than birds in the WO treatment. Birds in the WS treatment had higher d 45 body weight overall (P < 0.001) and in trials 1, 3 and 5, although overall body weight was lower in trials 1, 3 and 5 than in trials 2 and 4. Supplemental blue/green LED improved hock burn scores and increased d 45 body weight overall. However, trial differences suggest that more data is needed to determine whether supplementing blue/green LED to white LED improves body weight gain in mixed sex broiler chickens.
关键词： growth,stress,welfare,light emitting diode,broiler
更新于2025-09-23 15:21:01
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Evaluation of ion bombardment in DC magnetron sputtering DC
摘要： Momentum of ion bombardment in sputtering deposition process, which strongly depends on internal stress of thin film, has been evaluated regarding to a new parameter Pi we previously proposed for fine-tuning of mechanical, optical, electrical and magnetic properties. In this study, we demonstrate to estimate the Pi defined as (i/a) p, where i the ion flux, a the atom flux and p the ion’s momentum, by means of Langmuir probe and multi-grid analyzer in a function of negative bias voltage applied on substrates Vsub. As a result, it was found that the Pi was roughly proportional to Vsub except on lower voltage than 30 V. This indicates that the Pi should be measured plasma-diagnostically under incident ion energy as low as plasma potential.
关键词： Sputter,Thin film,Ion bombardment,Intrinsic stress,Plasma
更新于2025-09-23 15:21:01
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Connecting Diffraction-Based Strain with Macroscopic Stresses in Laser Powder Bed Fused Ti-6Al-4V
摘要： The laser powder bed fusion (LPBF) production process often results in large residual stress (RS) in the parts. Nondestructive techniques to determine RS are badly needed. However, a reliable quantification of macro-RS (i.e., stress at the component level) by means of diffraction-based techniques is still a great challenge, because the link between diffraction-based strain and macro-RS is not trivial. In this study, we experimentally determine (by means of in-situ synchrotron radiation diffraction) this link for LPBF Ti-6Al-4V. We compare our results with commonly used models to determine the so-called diffraction elastic constants (DECs). We show that LPBF materials possess different DECs than wrought alloys, simply because their microstructural and mechanical properties are different. We also show that the existing models can be used to calculate DECs only if high accuracy of the RS values is not required. If the peculiarities of the microstructure have to be taken into account (as is the case of additively manufactured materials), a radically new approach is desirable.
关键词： synchrotron radiation diffraction,Laser powder bed fusion,residual stress,Ti-6Al-4V,diffraction elastic constants
更新于2025-09-23 15:21:01
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Blue light-emitting diode irradiation promotes transcription factor EB-mediated lysosome biogenesis and lysosomal cell death in murine photoreceptor-derived cells
摘要： Exposure to blue light from light-emitting diodes (LEDs) is a source of damage for human eyes in today’s modern life. Although it is well known that blue light can cause cellular damage and death, the molecular mechanism underlying this is still not fully understood. Here, we demonstrated that exposure to blue LED light increased lysosome levels and perinuclear cluster formation in 661W murine photoreceptor-derived cells. Irradiation with blue LED light promoted the nuclear transport of transcription factor EB (TFEB) and a subsequent increase in lysosomal-related gene expression. Moreover, blue LED light induced morphological changes in lysosomal structure and lysosomal membrane permeabilization (LMP). These effects were suppressed by an antioxidant, N-acetylcysteine (NAC). Finally, a calcium ion chelator, BAPTA-AM, attenuated blue LED light-induced lysosomal biogenesis and cell death. Taken together, these findings suggest that oxidative stress under blue LED light increases lysosome levels via the TFEB pathway in a calcium-dependent manner, resulting in the accumulation of damaged lysosomes and subsequently lysosomal cell death. Our results imply that lysosomal homeostasis plays a key role in the maintenance of eye function and the progression of retinal diseases.
关键词： TFEB,Blue LED light,Calcium,Lysosome biogenesis,Oxidative stress,Lysosomal membrane permeabilization
更新于2025-09-23 15:21:01
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Application of infrared thermography to assess cassava physiology under water deficit condition
摘要： Water deficit stress is a major factor that inhibits the overall growth and development in cassava (Manihot esculenta), leading to decreased storage root yield. We conducted a study to investigate whether thermal sensing could be used to indicate water deficit stress and the health and yield of cassava crops in field. The objective of the study was to use thermal imaging to determine relationship between crop water stress index (CWSI) and physiological changes, and to identify the critical CWSI point in fields of cassava cv. Rayong 9 under well-irrigated and water-deficit conditions. At the time of storage root initiation (85 DAP [day after planting]), thermal imagery was collected and the physiological changes and growth characters were measured prior to storage root harvesting (162 DAP). Thermal infrared imager was used to measure the canopy temperature and CWSI of cassava plants. Net photosynthetic rate (Pn), stomatal conductance (gs) and transpiration rates (Tr) of cassava plants under water deficit conditions for 29 d (114 DAP) were significantly decreased, leading to delayed plant growth as compared to those under well-irrigated conditions. In contrast, air vapor pressure deficit (VPDair) and CWSI in drought-stressed plants were higher than well irrigated plants. High correlations between Tr/gs/Pn and CWSI were observed. The study concludes that CWSI is a sensitive indicator of water deficit stress caused due to stomatal function.
关键词： net photosynthetic rate,crop water stress index,thermal imagery,Cassava,stomatal conductance
更新于2025-09-23 15:21:01
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Stress Physiology of Tea in the Face of Climate Change || Molecular and Physiological Adaptations of Tea Plant in Response to Low Light and UV Stress
摘要： The sensory quality, economic value, and health functions of tea liquor depend on several metabolites in leaves of tea (Camellia sinensis L.), such as polyphenols (the most representative quality- and function-related compounds, especially catechins), caffeine, amino acids, aroma compounds, vitamins, and carbohydrates. The biosynthesis of these molecules is significantly affected by both management practices in the field and environmental factors, such as shading and ultraviolet (UV) stress. In this chapter, therefore, we review existing literature reporting the effects of shade and UV irradiances on tea plants with the aim to reappraise morphological, biochemical, physiological, and molecular responses found in this species. Cultivation of tea plants under shade can (i) induce anatomical and ultrastructural adaptations; (ii) influence leaf color, providing characteristic vivid greenness due to incremented chlorophyll content; (iii) decrease the risk of photoinhibition; and finally (iv) improve the quality of tea beverages by causing the reduction of the concentration of phenylpropanoids and caffeine (which contribute to astringency) while increasing the level of amino acids (the compounds that contribute to sweetness). However, the shade practice in tea is still subjected to controversy, and the correct managing of the shade practice is essential. Elevated UV irradiances, especially UV-B, can alter the plant morphology and affect several biochemical and physiological processes; most plant species respond to UV in a dose dependent manner. Protracted exposition to low UV-B doses (similar to UV peaks actually perceive by plants in the ambient) leads to an enhancement of phenylpropanoid metabolism and in particular stimulates the biosynthesis of UV-protecting flavonoids (mainly catechins). Conversely, UV-B doses much higher than those usually experienced in natural environment lead to the downregulation of the phenylpropanoid metabolism likely due to irreversible (to some extent) UV-triggered damages. The understandings of the reactions of tea plants to different light conditions, including situations of low light and high UV, are of pivotal importance to enhance both plant yield and tea quality by “driving” the accumulation of desired compounds in tea leaves.
关键词： Caffeine,UV stress,Amino acids,Low light,Catechins,Flavonoids,Tea plant
更新于2025-09-23 15:21:01
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[IEEE 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Shanghai (2018.8.8-2018.8.11)] 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Simulation research on wafer warpage and internal stress in the First Passivation process of eSiFO package
摘要： In the electronics packaging process, warpage and thermal stress are two important causes which lead to packaging failure. In this paper, ABAQUS is used to perform three-dimensional numerical simulation of eSiFo packaging products from the thermodynamic point of view. The effects of different structural parameters on wafer warpage and thermal stress in electronic packages are simulated. In the simulation part, single factor analysis, Taguchi orthogonal experiment design and finite element analysis are combined to obtain the optimized process parameters and perform simulation analysis. The result shows that the structural parameter that has the greatest influence on the von Mises stress value of the wafer is the window size. And the structural parameter that has the greatest influence on the wafer warpage is the Die thickness. The thickness of the adhesive layer and the thickness of the passivation layer have a relatively small effect on the von Mises stress and the warpage value of the wafer. Under the optimized process parameters, the maximum von Mises stress and the maximum warpage value are much smaller than the initial process.
关键词： Taguchi orthogonal experiment,optimization of process parameters,numerical simulation,Warpage,thermal stress
更新于2025-09-23 15:21:01
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The Influence of the EVA Film Aging on the Degradation Behavior of PV Modules Under High Voltage Bias in Wet Conditions Followed by Electroluminescence
摘要： The influence of the ethylene-vinyl acetate (EVA) film quality on potential induced degradation was studied on in-house developed mini modules with p-type monocrystalline silicon solar cells. The modules were assembled with EVA films of equivalent qualities, but different ages and exposed to an accelerated test (relative humidity = 85%, T = 60 °C, Vbias = +1000 V). The age of the EVA film was determined from the time we received the EVA film, and opened the sealed enclosure and the time of lamination. After the EVA film was removed from the sealed enclosure, it was kept in a dark place at room temperature. The storage times of the “fresh,” “aged,” and “expired” films were: less than 14 d, around 5 mo, and more than 5 years, respectively. While modules with a “fresh” EVA film exhibit almost no degradation, the modules with the “aged” EVA film degrade very rapidly and severely. Their degradation rate was around 0.2%/d during the 2000 h of damp heat test. We also observed a strong silver line corrosion, which occurs because of the peroxide leftovers in the “aged” EVA films.
关键词： photovoltaic (PV) modules,high voltage stress,EVA film,Degradation,potential induced degradation (PID),leakage current
更新于2025-09-23 15:21:01