Generalized Methodology for Array Processor Design of Real-time Systems

Many techniques and design tools have been developed for mapping algorithms to array processors. Linear mapping is usually used for regular algorithms. Large and complex problems are not regular by nature and regularization may cause a computational overhead which prevents the ability to meet real-time deadlines. In this paper, a systematic design methodology for mapping partially-regular as well as regular Dependence Graphs is presented. In this approach the set of all optimal solutions is generated under the given constraints. Due to nature of the problem and the tight timing constraints of real-time systems the set of alternative solutions is limited. An image processing example is discusse

Two-level pipelined systolic array graphics engine

The authors report a VLSI design of an advanced systolic array graphics (SAG) engine built from pipelined functional units which can generate realistic images interactively for high-resolution displays. They introduce a structured frame store system as an environment for the advanced SAG engine and present the principles and architecture of the advanced SAG engine. They introduce pipelined functional units into this SAG engine to meet the performance requirements. This is done by a formal approach where the original systolic array is represented at bit level by a finite, vertex-weighted, edge-weighted, directed graph. Two architectures built from pipelined functional units are described. A prototype containing nine processing elements was fabricated in a 1.6-¿m CMOS technolog

Assessment of lacrimal glands in thyroid eye disease with diffusion-weighted magnetic resonance imaging

Purpose: To assess the lacrimal glands in patients with thyroid eye disease with diffusion-weighted magnetic resonance (MR) imaging. Material and methods: This study was carried out on 44 consecutive patients (17 males, 27 females, with mean age 36 years) with thyroid eye disease and 20 age- and sex-matched volunteers. They underwent diffusion-weighted MR imaging of the orbit. The apparent diffusion coefficient (ADC) values of the lacrimal glands were calculated and correlated with the clinical activity score (CAS). Results: The mean ADC of lacrimal glands in thyroid eye disease (1.73 × 10-3 mm2/s) was significantly higher (p = 0.001) than that of volunteers (1.52 × 10-3 mm2/s). The cutoff ADC value of lacrimal gland used for differentiation of thyroid eye disease from volunteers was 1.62 × 10–3 mm2/s with an area under the curve value of 0.95 and an accuracy of 96%. There was significant difference (p = 0.03) in the ADC of the lacrimal glands in patients with active (n = 24) and inactive (n = 20) disease. The cutoff ADC value of the lacrimal gland used to suspect active disease was 1.76 × 10-3 mm2/s with an area under the curve value of 0.80 and an accuracy of 82%. There was positive correlation between the ADC value of the lacrimal glands and CAS (r = 0.73, p = 0.001). Conclusions: The ADC of the lacrimal glands is a non-invasive imaging parameter that can be used for diagnosis of thyroid eye disease and to predict the active form of the disease

Taxonomic revision of the cultivated species of Mimusops (Sapotaceae) in Egypt, with new records

During the process of updating horticultural records of this genus in Egypt, five problems were identified: lack of publications, lack of clarity between species, numerous errors of identifications, loss of earlier documented records of identity, as well as, the introduction and cultivation of new plants during the 19th Century added to the complexity of the problem. In this study, the taxonomic aspects of genus Mimusops, were thoroughly studied to identify the most reliable characters for taxon delimitation. Our assessment was based on morphological characters representing habit, leaves, petioles, flowering pedicels, buds, floral parts, fruit and seed. Fieldwork have revealed the presence of four species, of which Mimusops kummel and M. zeyheri are new records. The latter species is represented in Egypt by M. zeyheri var. laurifolia. This variety has been neglected by many authors. Additionally, Mimusops elengi L. was believed to be cultivated in Egypt, but no materials have been encountered that could confirm it. The specimens earlier identified as M. elengi actually belong either to M. kummel or to M. laurifolia. A detailed description of the genus and species with photographs, an identification key, and synonymy for each taxon are provided

Neuroprotective effect of renin angiotensin system blockers on experimentally induced Alzheimer’s disease in rats

Background: Alzheimer’s disease (AD) is a major world-wide health problem. Much evidence points to a link between hypertension and AD. However, the exact effects of different antihypertensive drugs on AD need to be more assessed. The aim was to evaluate and compare the possible effects of perindopril, and candesartan on cognitive impairment, oxidative stress markers, and brain concentrations of amyloid beta-peptide (Aβ-P) in a rat model of induced dementia.Methods: Thirty-two adult male Wistar rats were distributed among 4 groups; (1) normal controls; (2) rats with dementia induced by intracerebroventricular administration of streptozotocin (ICV-STZ) and received no treatment; (3) ICV-STZ rats treated orally with perindopril for 3 weeks; and (4) ICV-STZ rats treated orally with candesartan for 3 weeks. The assessed parameters were spatial memory by Morris Water Maze test, brain tissue level of total antioxidant capacity (TAC), reduced glutathione (GSH), lipid peroxidation product (malondialdehyde [MDA]), and Aβ-P.Results: Both perindopril and candesartan attenuated STZ-induced memory impairment, caused a significant increase in TAC and GSH levels, reduced MDA levels, whereas only candesartan significantly reduced Aβ-P levels.Conclusions: This study reports that candesartan and perindopril can reverse the free radical induced damages and resultant memory defects, and may suggest candesartan as worthy drugs for prevention of Aβ-P deposition in this animal model of AD

Design of Integrated Microwave Frequency Synthesizer-Based Dielectric Sensor Systems

Dielectric sensors have several biomedical and industrial applications where they are used to characterize the permittivity of materials versus frequency. Characterization at RF/microwave frequencies is particularly useful since many chemicals/bio-materials show significant changes in this band. The potential system cost and size reduction possible motivates the development of fully integrated dielectric sensor systems on CMOS with high sensitivity for point-of-care medical diagnosis platforms and for lab-on-chip industrial sensors. Voltage-controlled oscillator (VCO)-based dielectric sensors embed the sensing capacitor within the excitation VCO to allow for self-sustained measurement of the material under test (MUT)-induced frequency shift with simple and precise readout circuits. Despite their advantages, VCO-based sensors have several design challenges. First, low frequency noise and environmental variations limit their sensitivity. Also, these systems usually place the VCO in a frequency synthesizer to control the sample excitation frequency which reduces the resolution of the read-out circuitry. Finally, conventional VCO-based systems utilizing LC oscillators have limited tuning range, and can only characterize the real part of the permittivity of the MUT. This dissertation proposes several ideas to: 1) improve the sensitivity of the system by filtering the low frequency noise and enhance the resolution of the read-out circuitry, 2) improve the tuning range, and 3) enable complex dielectric characterization in VCO/synthesizer-based dielectric spectroscopy systems. The first prototype proposes a highly-sensitive CMOS-based sensing system for permittivity detection and mixture characterization of organic chemicals at microwave frequencies. The system determines permittivity by measuring the frequency difference between two VCOs; a sensor oscillator with an operating frequency that shifts with the change in tank capacitance due to exposure to the MUT and a reference oscillator insensitive to the MUT. This relative measurement approach improves sensor accuracy by tracking frequency drifts due to environmental variations. Embedding the sensor and reference VCOs in a fractional-N phase-locked loop (PLL) frequency synthesizer enables material characterization at a precise frequency and provides an efficient material-induced frequency shift read-out mechanism with a low-complexity bang-bang control loop that adjusts a fractional frequency divider. The majority of the PLL-based sensor system, except for an external fractional frequency divider, is implemented with a 90 nm CMOS prototype that consumes 22 mW when characterizing material near 10 GHz. Material-induced frequency shifts are detected at an accuracy level of 15 ppmrms and binary mixture characterization of organic chemicals yield maximum errors in permittivity of <1.5%. The second prototype proposes a fully-integrated sensing system for wideband complex dielectric detection of MUT. The system utilizes a ring oscillator-based PLL for wide tuning range and precise control of the sensor's excitation frequency. Characterization of both real and imaginary MUT permittivity is achieved by measuring the frequency difference between two VCOs: a sensing oscillator, with a frequency that varies with MUT-induced changes in capacitance and conductance of a delay-cells' sensing capacitor loads, and a MUT-insensitive reference oscillator that is controlled by an amplitude-locked loop (ALL). The fully integrated system is fabricated in 0.18 μm CMOS, and occupies 6.25 mm2 area. When tested with common organic chemicals (ε`r < 30), the system operates between 0.7-6 GHz and achieves 3.7% maximum permittivity error. Characterization is also performed with higher ε`r water-methanol mixtures and phosphate buffered saline (PBS) solutions, with 5.4% maximum permittivity error achieved over a 0.7-4.77 GHz range

Removal of Enteric Viruses By Ultrafiltration Membranes

Application of low pressure membranes in drinking water treatment, including both microfiltration (MF) and ultrafiltration (UF), have witnessed a rapid increase in the past decades. Low pressure membranes are considered a good technology in retrofitting existing conventional drinking water treatment plants or in newly constructed plants to meet the stringent regulations for drinking water treatment that aim at preventing health risks of waterborne diseases. Enteric viruses are one of the major types of waterborne pathogens, and they can be commonly found and are persistent in the environment. Both the United States and Canada require a 99.99% (4-log) removal of viruses during the drinking water treatment train. Unlike MF membranes, UF membranes have a very good potential for removing enteric viruses from the water due to their smaller pores comparable to the size of viruses. Drinking water regulations/guidelines in both the United States and Canada do not grant UF membranes any removal credit for viruses by default; however they have the provision that, in certain cases, virus removal credit may be granted based on pilot scale challenge testing. A better understanding of the interaction between the UF membranes and virus rejection can help to establish a removal credit for UF membranes. An essential part of this will be the effect of the membrane operation on the rejection of viruses to determine if UF membranes can offer a consistent removal of viruses. Membrane fouling is one of the major problems in membrane operation and it can affect the rejection characteristics of the membrane and improve its performance. The aim of this study was to investigate the removal of virus surrogates (MS2 and φX174 bacteriophage) using a commercial UF membrane under different conditions, to obtain information about the removal mechanisms of viruses. The experimental filtration unit was designed to have similar conditions like the full scale membrane treatment plants. The UF membrane used in this study provided very good removal of both MS2 and φX174 bacteriophage. The obtained results were consistent and in agreement with the expected removals based on the membrane characterization results and types of virus surrogate. As part of this work, a detailed study to improve methods for characterizing the pore size distribution of membranes was conducted. In the second part of the study, two different types of surface waters were used to study the effect of membrane fouling on virus removal. It was found that mainly hydraulically irreversible fouling could significantly improve the virus removal by UF membranes. Different cleaning regimes that are used in treatment plants had varying effects on virus removal. After maintenance cleaning, virus removal remained higher than that of clean membranes, and only chemical cleaning was effective for completely removing membrane foulants and returning virus removal back to base levels. Advanced analytical techniques were used to define the nature of the fouling layer on the membrane surface and how the foulants affected the rejection of viruses. Finally, our study showed that UF membranes are a robust treatment technology for removing different types of enteric virus surrogates from water under different operational conditions. Close monitoring of the UF unit performance and direct integrity testing can possibly detect membrane problems that can affect the rejection of viruses. Based on the virus physical characteristics and a detailed study of the membrane surface characteristics, especially the pore size distribution of the membrane, the removal of the specific virus can be closely estimated

The Outcome of Diabetic Patients with Cardiomyopathy in Critical Care Unit: Hospital and Short-Term Outcome in a Period of Six Months to One Year

BACKGROUND: Diabetes mellitus (DM) is a major risk factor for heart failure (HF) and coronary artery disease (CAD). DM may cause structural changes involving the left ventricle (LV) systolic and diastolic function. AIM: To compare patients who have diabetes and ischemic cardiomyopathy (ICM) to those with diabetic cardiomyopathy (DMCMP) regarding LV systolic function, diastolic function, in hospital long term and short-term mortality. METHODS: Ninety diabetic patients with heart failure and left ventricular ejection fraction (LVEF) ≤ 35%, admitted to Critical Care Medicine department Cairo University were divided into two groups based on coronary angiography results; group I (ICM) n = 48 patients and group II (DMCMP) n = 42 patients. RESULTS: Group I patients had higher mean age (63 ± 7 years), (p = 0.004), Hypertension (p ˂ 0.001) and dyslipidemia (p = 0.008) were significantly more present in group I compared to group II. No significant differences were found regarding LVEF, global longitudinal strain (GLS), E/A and E/É ratio in both groups. A significant difference in the wall motion score index (WMSI) in group I; (1.4 ± 0.4) versus group II; (1.1 ± 0.2), (p = 0.005) was found. In the study, 6 patients had a cardiogenic shock with no documented in-hospital mortality. At 6 months, statistically, significantly higher mortality rates were found in group I, (p = 0.006), while at one year there was no significant difference in the mortality between the two groups, (p = 0.077). In comparison of the survived and non-survived patients at 6 months and one year in group I (ICM) there was a significant difference in LVEF (40 ± 6% vs 23 ± 6%, p ˂ 0.001), GLS (- 8.1 ± 2.4 vs - 4.6 ± 2.6, p = 0.007), E/A (1.25 ± 0.91 vs 1.8 ± 0.5, p = 0.038), E/É (11.68 ± 7.5 vs 21.3 ± 3.6, p = 0.001) respectively. In group ll (DMCMP) there was no documented mortality at 6 months follow up, however, at one year there was statistically significant difference in the mortality between survived and non-survived patients; the LVEF (35 ± 8% vs 25 ± 2%, p = 0.014), GLS (-7.9 ± 2.9% vs -5 ± 0.1%, p = 0.032), E/A (1.45 ± 0.8 vs 3.3 ± 0, p = 0.006) respectively. The E/É ratio in group ll was not significantly different between the groups (15.73 ± 5.3 vs 15 ± 1, p = 0.873). CONCLUSION: The combination of cardiomyopathy and diabetes affects LV systolic and diastolic function; however; ischemic cardiomyopathy and diabetic cardiomyopathy had a similar systolic and diastolic function. Ischemic cardiomyopathy is associated with worse prognosis compared to diabetic cardiomyopathy

Impact of body temperature and serum procalcitonin on the outcomes of critically ill neurological patients

AbstractIntroductionFever is common in patients with acute stroke, and mostly it is due to infectious complications. The neurologic effects of fever are significant, increased temperature in the post-injury period has been associated with increased cytokine activity and increased infarct size.AimTo test the hypothesis that fever and increased serum procalcitonin are associated with poor outcomes after neurological injury.MethodologyFifty patients (30 males (60%) and 20 females (40%) mean 43.8±11.7years) were divided into two groups: Group I: 25 traumatic patients (i.e., head injury) and Group II: 25 non-traumatic patients (i.e., stroke). Temperature was measured from admission until the patients were discharged or died, and PCT was measured on day 1 of admission and after 48h of admission.ResultsFever has been associated with poor outcome, as fever is linked to worse GCS scores (12.6±1.2 vs. 7.7±2.6 in patients with fever, P 0.001), longer MV durations (3.6±1.0 vs. 22.4±9.1days, in patients with fever, P 0.001), longer ICU length of stay (8.1±4.7 vs. 23.0±8.0days in patients with fever, P 0.001) and increased mortality (P=0.001). There were significantly higher PCT levels in the mortality group versus the survived group at day 1 (4.15±0.82 vs. 2.47±0.059ng/ml, respectively, P 0.0001) and after 48h of admission (5.20±1.14 vs. 3.19±0.092ng/ml, respectively, P 0.0001).ConclusionFever had a strong link to worse GCS, longer MV durations, increased length of ICU stay, higher mortality rates and worse overall outcomes in neurocritical patients. High PCT levels can predict mortality in those patients