Energy-Saving Design for Hydraulic Tube Bender

Generally speaking, hydraulic control systems can be divided into two different driving concepts. The first one is the well-known hydraulic valve-controlled system and the second one is the pump-controlled system. The former possesses the feature of fast dynamic response. However, the poor energy-saving performance is its major fault. On the contrary, the hydraulic pump-controlled system has the significant advantage of energy-saving which meets the current demand in modem machine design. In this paper, the simulation analysis using MatLab/SimuLink and DSHplus software for a newly developed energy-saving hydraulic tube bender is conducted. Instead of the conventional fixed displacement hydraulic pump, the new hydraulic tube bender utilizes an internal gear pump with AC servomotor as its driving power source. In the new energy-saving hydraulic circuit, the use of conventional pressure relief valve and unloading valve are no longer necessary since the demanded flow-rate and pressure output can be precisely obtained by continuously changing the speed of the AC servomotor. In addition, two closed-loop control schemes using fuzzy sliding-mode controller are adopted and compared. To compare the energy-saving control systems, such as load-sensing control system, constant supply pressure control scheme and conventional hydraulic control scheme. Furthermore, the simulation results also show that the newly developed hydraulic tube bender can save up to 43% of energy consumption in a working cycle as compared to the conventional hydraulic tube bender.     

Development of an unconventional electro-hydraulic proportional valve with fuzzy-logic controller for hydraulic presses

A micro slit die easily manufactured using a micro electrical discharge machining (MEDM) is proposed for micro heat sink fabrication. In the investigations described in this paper, processed concave and rectangular shaped copper foils were combined piece by piece to form an assembled electrode. This electrode was used to fabricate a micro slit die. This die included 15 micro fins in a small tungsten carbide plate. The micro heat sink was made by applying a pressing or scraping method when the micro slit die was used. The experiments showed that debris, produced by the MEDM, might cause a discharge concentration effect because of the narrow gaps between the workpiece and electrode. Parts of the micro fin were seriously melted during this process. Flushing dielectric could effectively remove the debris from the narrow gap, generating an appropriate discharge dispersing effect. However, the discharge effect was unstable when large flushing pressure was applied, thus reducing the machining precision. The micro fins were formed into a rectangular shape using kerosene as the MEDM dielectric. Using distilled water as the MEDM dielectric produced a higher material removal rate and serious assembled electrode wear. Therefore, the micro fins formed as triangle profiles. The micro heat sink was higher even when the pressing method was used. The heat sink deviated and was full of burrs on the fin edge when the scraping method was used.     

Effects of chitosan and whole raw soybeans on ruminal fermentation and bacterial populations,and milk fatty acid profile in dairy cows

The objective of this study was to evaluate whether providing chitosan (CHI) to cows fed diets supplemented with whole raw soybeans (WRS) would affect the nutrient intake and digestibility, ruminal fermentation and bacterial populations, microbial protein synthesis, N utilization, blood metabolites, and milk yield and composition of dairy cows. Twenty-four multiparous Holstein cows (141 ± 37.1 d in milk, 38.8 ± 6.42 kg/d of milk yield; mean ± SD) were enrolled to a 4 × 4 Latin square design experiment with 23-d periods. Cows were blocked within Latin squares according to milk yield, days in milk, body weight, and rumen cannula (n = 8). A 2 × 2 factorial treatment arrangement was randomly assigned to cows within blocks. Treatments were composed of diets with 2 inclusion rates of WRS (0 or 14% diet dry matter) and 2 doses of CHI (0 or 4 g/kg of dry matter, Polymar Ciência e Nutrição, Fortaleza, Brazil). In general, CHI+WRS negatively affected nutrient intake and digestibility of cows, decreasing milk yield and solids production. The CHI increased ruminal pH and decreased acetate to propionate ratio, and WRS reduced NH₃-N concentration and acetate to propionate in the rumen. The CHI reduced the relative bacterial population of Butyrivibrio group, whereas WRS decreased the relative bacterial population of Butyrivibrio group, and Fibrobacter succinogenes, and increased the relative bacterial population of Streptococcus bovis. No interaction effects between CHI and WRS were observed on ruminal fermentation and bacterial populations. The CHI+WRS decreased N intake, microbial N synthesis, and N secreted in milk of cows. The WRS increased N excreted in feces and consequently decreased the N excreted in urine. The CHI had no effects on blood metabolites, but WRS decreased blood concentrations of glucose and increased blood cholesterol concentration. The CHI and WRS improved efficiency of milk yield of cows in terms of fat-corrected milk, energy-corrected milk, and net energy of lactation. The CHI increased milk concentration [g/100 g of fatty acids (FA)] of 18:1 trans-11, 18:2 cis-9,cis-12, 18:3 cis-9,cis-12,cis-15, 18:1 cis-9,trans-11, total monounsaturated FA, and total polyunsaturated FA. The WRS increased total monounsaturated FA, polyunsaturated FA, and 18:0 to unsaturated FA ratio in milk of cows. Evidence indicates that supplementing diets with unsaturated fat sources along with CHI negatively affects nutrient intake and digestibility of cows, resulting in less milk production. Diet supplementation with CHI or WRS can improve feed efficiency and increases unsaturated FA concentration in milk of dairy cows.     

Design,Synthesis, and Characterization of a Photoactivatable Caged Prodrug of Imatinib

Imatinib is the first protein kinase inhibitor approved for clinical use and is a seminal drug for the concept of targeted therapy. Herein we report on the design, synthesis, photokinetic properties, and in vitro enzymatic evaluation of a photoactivatable caged prodrug of imatinib. This approach allows spatial and temporal control over the activation of imatinib triggered by ultraviolet light. The successful application of the photoactivation concept to this significant kinase inhibitor provides further evidence for the caging technique as a feasible approach in the kinase field. The presented photoactivatable imatinib prodrug will be highly useful as a pharmacological tool to study the impact of imatinib toward biological systems in greater detail.     

Modelling the surface circulation and thermal structure of a tropical reservoir using three‐dimensional hydrodynamic lake model and remote‐sensing data

Diurnal variations in surface circulation, heat budget and thermal structure were investigated in a tropical reservoir using a synergistic approach that combines in situ observations, remote‐sensing data and numerical modelling. The study area, the Itumbiara Reservoir (Brazil) at the beginning of the austral winter, is characterized by the presence of a weak thermal stratification and the passage of several cold fronts. Both in situ observations and numerical modelling showed that the surface circulation is wind‐driven. The strongest water current was observed at 13:00 h, which lagged behind the strongest wind. The daily heat budget was negative during the period and was controlled by short‐wave radiation and latent heat flux. The diurnal cycle of stratification was at its maximum at 17:00 h, and the surface mixed layer deepens at night. The colder waters of the Paranaíba River contribute to the stability of the water column near the river‐reservoir transition zone.     

Norketamine,the Main Metabolite of Ketamine,Induces Mitochondria-Dependent and ER Stress-Triggered Apoptotic Death in Urothelial Cells via a Ca2+-Regulated ERK1/2-Activating Pathway

Ketamine-associated cystitis is characterized by suburothelial inflammation and urothelial cell death. Norketamine (NK), the main metabolite of ketamine, is abundant in urine following ketamine exposure. NK has been speculated to exert toxic effects in urothelial cells, similarly to ketamine. However, the molecular mechanisms contributing to NK-induced urothelial cytotoxicity are almost unclear. Here, we aimed to investigate the toxic effects of NK and the potential mechanisms underlying NK-induced urothelial cell injury. In this study, NK exposure significantly reduced cell viability and induced apoptosis in human urinary bladder epithelial-derived RT4 cells that NK (0.01–0.5 mM) exhibited greater cytotoxicity than ketamine (0.1–3 mM). Signals of mitochondrial dysfunction, including mitochondrial membrane potential (MMP) loss and cytosolic cytochrome c release, were found to be involved in NK-induced cell apoptosis and death. NK exposure of cells also triggered the expression of endoplasmic reticulum (ER) stress-related proteins including GRP78, CHOP, XBP-1, ATF-4 and -6, caspase-12, PERK, eIF-2α, and IRE-1. Pretreatment with 4-phenylbutyric acid (an ER stress inhibitor) markedly prevented the expression of ER stress-related proteins and apoptotic events in NK-exposed cells. Additionally, NK exposure significantly activated JNK, ERK1/2, and p38 signaling and increased intracellular calcium concentrations ([Ca²⁺]_i). Pretreatment of cells with both PD98059 (an ERK1/2 inhibitor) and BAPTA/AM (a cell-permeable Ca²⁺ chelator), but not SP600125 (a JNK inhibitor) and SB203580 (a p38 inhibitor), effectively suppressed NK-induced mitochondrial dysfunction, ER stress-related signals, and apoptotic events. The elevation of [Ca²⁺]_i in NK-exposed cells could be obviously inhibited by BAPTA/AM, but not PD98059. Taken together, these findings suggest that NK exposure exerts urothelial cytotoxicity via a [Ca²⁺]_i-regulated ERK1/2 activation, which is involved in downstream mediation of the mitochondria-dependent and ER stress-triggered apoptotic pathway, consequently resulting in urothelial cell death. Our findings suggest that regulating [Ca²⁺]_i/ERK signaling pathways may be a promising strategy for treatment of NK-induced urothelial cystitis.     

Effect of hypoglycemia on beta-adrenergic sensitivity in normal and type 1 diabetic subjects

OBJECTIVE: The purpose of this study was to assess the potential role of reduced tissue sensitivity to catecholamines in the pathogenesis of hypoglycemia unawareness in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: The effect of a single episode of hypoglycemia on beta-adrenergic sensitivity was studied in 10 type 1 diabetic patients with apparently normal awareness of hypoglycemia (age 29 +/- 5 years, diabetes duration 13 +/- 8 years, HbA1c 7.3 +/- 0.9%) and 10 age-matched healthy control subjects. Beta-adrenergic sensitivity was measured with the isoproterenol test after a hyperinsulinemic euglycemic clamp and after a hyperinsulinemic hypoglycemic clamp. Beta-adrenergic sensitivity was expressed as the dose of intravenous isoproterenol that increased the heart rate by 25 beats/min (IC25). RESULTS: During hypoglycemia, diabetic subjects had an impaired plasma epinephrine response compared with that of the control subjects (16.7 +/- 5.0 vs. 40.1 +/- 6.8 ng/ml, P = 0.02). In control subjects, the IC25 was lower after hypoglycemia than after euglycemia (0.83 +/- 0.22 vs. 1.13 +/- 0.21 microg, P = 0.02) indicating an increase in beta-adrenergic sensitivity. In diabetic subjects, on the other hand, the IC25 was greater after hypoglycemia than after euglycemia (1.00 +/- 0.26 vs. 0.65 +/- 0.14 microg, P = 0.04), indicating a decrease in beta-adrenergic sensitivity. CONCLUSIONS: In normal subjects, a single episode of hypoglycemia increases beta-adrenergic sensitivity. In diabetic subjects, in contrast, hypoglycemia reduces beta-adrenergic sensitivity. These results provide evidence that in type 1 diabetic patients, some maladaptation of tissue sensitivity to catecholamines contributes to the development of hypoglycemia unawareness. A unifying hypothesis is presented for the pathogenesis of hypoglycemia unawareness in type 1 diabetic patients incorporating the concepts of both a reduced catecholamine response and reduced adrenergic sensitivity     

Reliability and validity of depressive personality disorder

OBJECTIVE: Depressive personality disorder was introduced into DSM-IV's appendix amid controversy. While that disorder appears to be a reliable and valid one, the authors offer new data about its relationship to major depression, dysthymic disorder, and other personality disorders. METHOD: The authors assessed 54 subjects with early-onset, long-standing mild depressive features for depressive personality disorder, axis I and axis II disorders, family history, and treatment history; they conducted follow-up interviews 1 year after the baseline assessment. Subjects with (N=30) and without (N=24) depressive personality disorder were characterized and compared in terms of those variables. RESULTS: Although depressive personality disorder and dysthymia co-occurred in some subjects, 63% of subjects with depressive personality disorder did not have dysthymia, and 60% did not have current major depression. Although subjects with depressive personality disorder were more likely than the mood disorder comparison group to have another personality disorder, 40% had no such disorder. Contrary to study hypotheses, mood disorder was not more common in first-degree relatives of subjects with depressive personality disorder than in relatives of the comparison group. Subjects with and without depressive personality disorder had similar rates of past treatment with medication and psychotherapy; however, the duration of psychotherapy was significantly longer for subjects with than for those without depressive personality. The depressive personality diagnosis was relatively stable over the 1-year follow-up period. CONCLUSIONS: Depressive personality disorder appears to be a relatively stable condition with incomplete overlap with axis I mood disorders and personality disorders. Further studies are needed to better characterize its treatment response and relationship to axis I mood disorders.     

Generation-recombination transient effects in partially depletedSOI transistors: systematic experiments and simulations

A synthesis of the most frequent transient phenomena due to floating-body effects in partially depleted SOI MOSFET's is presented. The dominant physical mechanisms are examined through a variety of experiments. Comprehensive models which predict the transient effects are included in SOISPICE. Simulated transients involving both generation and recombination are fully validated by the experiments and are shown to he useful for reliable carrier lifetime extraction as well as SOI circuit simulation