Real-time heating and power characterization of cells in standard cell designs

In today's digital electronic integrated circuits device heating is one of the most critical issues. Overheating can cause failures in functionality and device malfunction. In certain circumstances overheating of ICs can cause physical destruction of the device itself. This paper introduces a solution to determine cell and gate heating curves across the standard cell IC's surface. The presented methodology and toolset is tightly integrated into standardized logic simulator engines thus providing digital circuit designers a low-level, cell-resolution temperature distribution map during logic simulations. Actual temperatures of each consisting cell of the design can be monitored throughout the whole logic simulation. By being able to monitor temperatures of digital cells during initial simulations, it allows us to detect hot-spots and overheating caused malfunctions far before manufacture. By using the spatial location and temperature magnitude of hot-spots acquired from the presented methodology, place and route (P&R) tools can be driven to change cell placement and routing in order to avoid heating caused failures. Additionally, cooling solutions can be developed using the simulated temperature maps of the IC's surface. This paper also presents various aspects of power characterization methods which were used throughout the experiments.     

Temperature dependent timing in standard cell designs

This paper proposes a methodology to simulate temperature dependent timing in standard cell designs. Temperature dependent timing characteristics are derived from standard delay format (SDF) files that are created by synthesis tools automatically based on SPICE characterizations. In addition, a fast calculation of temperatures using the equivalent Foster RC network is presented. A case study is also presented in this paper where the temperature dependent frequency variation of a ring oscillator is simulated demonstrating the necessity of temperature dependent timing simulations. An adaptively refineable partitioning method for simulating standard cell designs logi-thermally is proposed as well. This paper also introduces recent enhancements in the CellTherm logi-thermal simulator developed in the Department of Electron Devices, BME, Hungary. Finally, the simulation results are compared and verified with the SPICE compatible ELDO analog simulator from Mentor Graphics.     

Cell-Permeable Succinate Rescues Mitochondrial Respiration in Cellular Models of Statin Toxicity

Statins are the cornerstone of lipid-lowering therapy. Although generally well tolerated, statin-associated muscle symptoms (SAMS) represent the main reason for treatment discontinuation. Mitochondrial dysfunction of complex I has been implicated in the pathophysiology of SAMS. The present study proposed to assess the concentration-dependent ex vivo effects of three statins on mitochondrial respiration in viable human platelets and to investigate whether a cell-permeable prodrug of succinate (complex II substrate) can compensate for statin-induced mitochondrial dysfunction. Mitochondrial respiration was assessed by high-resolution respirometry in human platelets, acutely exposed to statins in the presence/absence of the prodrug NV118. Statins concentration-dependently inhibited mitochondrial respiration in both intact and permeabilized cells. Further, statins caused an increase in non-ATP generating oxygen consumption (uncoupling), severely limiting the OXPHOS coupling efficiency, a measure of the ATP generating capacity. Cerivastatin (commercially withdrawn due to muscle toxicity) displayed a similar inhibitory capacity compared with the widely prescribed and tolerable atorvastatin, but did not elicit direct complex I inhibition. NV118 increased succinate-supported mitochondrial oxygen consumption in atorvastatin/cerivastatin-exposed platelets leading to normalization of coupled (ATP generating) respiration. The results acquired in isolated human platelets were validated in a limited set of experiments using atorvastatin in HepG2 cells, reinforcing the generalizability of the findings.     

Wood-plastic composites based on HDPE and ionic liquid additives

The improvement of wood-plastic composites properties by additives and compatibilizers is a critical issue to produce value-added materials. High-density polyethylene-wood composites have been obtained through compression molding at 140 °C, using two types of additives, namely methyltrioctylammonium bis (trifluoromethylsulfonyl)imide and trihexyltetradecylphosphonium bis (2,4,4-trimethylpentyl) phosphinate room temperature ionic liquids. The ionic liquids improve the interfacial adhesion between the wood and the polymer phases, contributing to an increased stability of the material to water action and to an improved impact resistance and tensile strength in comparison with the reference. Also, the FTIR spectroscopy tests have proven a higher resistance of the ionic liquid-containing composites to accelerated photooxidation. Preliminary screening tests have also proven the antifungal character of the ionic liquids used in this study against brown rot (Postia placenta). This study opens new insights in the domain of polymeric composite materials, through documenting the possibility of blending new types of chemically distinct materials, difficult to be achieved by traditional functionalization/derivatization routes.     

Noise Test on Rotating Electrical Motors Under Load

ABSTRACT

The noise of the rotating electrical motor can be strongly influenced by the change in the loading conditions. In extreme cases a noise component of electromagnetic origin may increase by 36 dB or decrease by 24 dB upon loading.Protection of a human being from the noise depends on the noise characteristics of the el. machine under operating conditions. The standards relevant to the noise qualification measurements permit the use of the sound power level determined under no–load conditions, if the noise of the machine does not vary with the change in the load. This is a concession that is made because it is difficult to separate the noise level of the loading machine from the noise of the electric motor being investigated. This paper presents several methods, and their analyses, where the sound power level emitted by a loaded electrical motor can be determined experimentally in an industrial environment.Wide ranging experimental work has been made in this field, which will be be presented at the end of the paper.     

Individualized Follow-up of Pregnant Women with Asymptomatic Autoimmune Thyroid Disease

Maternal hormones are essential for the normal fetal development during pregnancy. Autoimmune thyroid disease is a frequent pathology in our iodine replete region. The aim of this study is to evaluate the occurrence of subclinical hypothyroidism (SCH) in cases with known autoimmune thyroid disease, which were in a euthyroid state prior to pregnancy, and to assess the association between supplemental treatments administered and the outcome of the pregnancy. The study is a prospective interventional controlled study. The two cohorts comprise the interventional group, consisting of 109 pregnant women with known autoimmune asymptomatic thyroid disease, without any levothyroxine (LT4) treatment and an aged-matched control group, with an unknown thyroid disease. After the pregnancy, a monthly evaluation of TSH, FT3, and FT4 was performed. Offspring evaluation was made at birth time. 88.8% of the women developed SCH in the first four weeks of pregnancy. Average LT4 doses increased as the pregnancy progressed. The monthly adjustment was 12.5 or 25 μg. All SCH cases developed in the first trimester of pregnancy. There was no significant difference regarding the gestational week, weight, or length at birth between the interventional group and controls, when TSH values were in the optimal range, during the whole pregnancy. Premature birth was described in one case in the interventional group.     

Prognostic significance of 25‐hydroxivitamin D entirely explained by a higher comorbidity burden: Experience from a South‐Eastern European Dialysis Cohort

Vitamin D deficiency is still a common problem particularly in the elderly and in individuals with various degrees of renal impairment. The present study aimed to evaluate the association between plasma concentrations of 25(OH)D and death in a large cohort of prevalent patients on hemodialysis (HD) from south‐east Romania, a typical Balkan region. This is an observational prospective study that included a total of 570 patients on maintenance HD. Study patients were classified into three groups by baseline 25(OH)D levels: (1) sufficient 25(OH)D—i.e., >30 ng/mL; (2) insufficient 25(OH)D—i.e., between 10 and 29 ng/mL; and (3) deficient 25(OH)D—i.e., <10 ng/mL. During the follow‐up period of 14 months, 68 patients (11.9%) died, the Kaplan–Meier analysis showing significant differences in all‐cause mortality for chronic kidney disease patients in different 25(OH)D groups (P = 0.002). Unadjusted Cox regression analysis also showed significant differences in survival. The multivariate Cox regression model showed no significant differences in survival according to vitamin D levels. Hazard ratio for death in the “<10 ng/mL” group was 1.619 (P = 0.190) and in the “10–30 ng/mL” group was 0.837 (P = 0.609). In our dialysis population with a high comorbidity burden, low 25(OH)D concentration was not associated with mortality in the adjusted Cox model, suggesting that vitamin D deficiency could represent only a non‐specific marker for a poor health status, with less impact on mortality.