Miracle-dz/UniFAR-FTUs huggingface dataset:
Precise control law of MMC and its application in reducing capacitor voltage ripple by injecting circulating current

Modular multilevel converter (MMC) has been a research hotspot in the past decade in the high-voltage high-power applications. The basic working principle is analyzed in depth in this paper firstly. A precise control law is deduced to control the output voltage and the circulating current directly and precisely. Different from the conventional control law, arm inductor voltages are considered in the proposed method. It is proved that in terms of eliminating the circulating current, the effect of this control law is approximately equivalent to the conventional closed loop control with circulating current suppressing controller (CCSC). Based on this control law, the operation of MMC is further analyzed and the modulation index limitation is offered when the circulating current is eliminated. Furthermore, this paper deals with reducing the capacitor voltage ripple. After comparison, the paper gives an optimized form for single-phase MMC when only second-order circulating current is injected. The analysis can be extended to three-phase MMC. Theoretical analysis and simulations verify all the conclusions.
Design of a fully integrated RF transceiver using noise modulation

The aim of this project is to build the radio for sensor networks in low throughput applications. Robust communication and low power consumption are the main challenges in building such networks. Wideband modulation provides this robustness by spreading the spectrum of an information signal over a wide frequency spectrum using a broadband reference signal. Broadband spreading is hampered by long acquisition times, because synchronization takes place under very low SNR conditions. By sending the reference signal with the information signal, this problem is resolved. Since the reference signal does not have to be regenerated at the receiver, pure noise can be used. Noise Modulation techniques do not require coordination between the transmitter and the receiver. At the receiver just a correlation is needed between the received information signal and the received reference signal to reconstruct the information data. This attractive property of the Noise Modulation concept may allow building really low power receivers with a current consumption of less than 100 μA, compatible with energy harvesting (no batteries). In this thesis, a brief description of the Noise Modulation in both the frequency as well as in the time domain is presented. Especially the time analysis appears useful to make various design choices on the system level like the choice of frequencies, type of multiplier and type of baseband filtering. After that the focus is moved to the low power receiver in CMOS, with focus on the design of the correlater. Since the noise contribution of this correlater is very large, because it depends on the square value of its input signal, the receiver will consume high current if a long distance radio-link is needed. Therefore we had to review important parameters in our system, namely the transmitted power, the radio range, the overdrive voltage of the correlater transistors and the current consumption of the Front End, to make some rough decisions in order to meet the goal of designing a low power receiver.
Desulfurization of Iron Ores: Processes and Challenges

Various studies have been increasingly performed on the reduction of sulfur content of iron ores and concentrates. The presence of sulfur in these materials causes technical problems in steel and alloys and environmental issues in the sintering of iron ore process. The achievement of higher sulfur removal rates has been an important goal since the development of sulfur removal techniques. In this research, an effort is made to separately introduce the various processes, industrial practices, and fundamental research activities to remove sulfur from iron ores, concentrates, or roasted iron ores. In this way, the optimized condition and latest innovations in sulfur removal using flotation are reviewed and the development of leaching and bioleaching techniques for sulfur reduction is introduced; following the development of thermal decomposition, physical separation methods, and magnetic separation technique are discussed. In each section, a brief introduction of fundamentals for the sulfur removal techniques and their potential advantages for sulfur removal are described and challenges for each technique are presented. Finally, the techniques are compared from technical, economic and environmental viewpoints, and future trends in desulfurization of iron ores are presented.
Gestational and lactational exposure of rats to xenoestrogens results in reduced testicular size and sperm production.

This study assessed whether exposure of male rats to two estrogenic, environmental chemicals, 4-octylphenol (OP) and butyl benzyl phthalate (BBP) during gestation or during the first 21 days of postnatal life, affected testicular size or spermatogenesis in adulthood (90-95 days of age). Chemicals were administered via the drinking water or concentrations of 10-1000 micrograms/l (OP) or 1000 micrograms/l (BBP), diethylstilbestrol (DES; 100 micrograms/l) and an octylphenol polyethoxylate (OPP; 1000 micrograms/l), which is a weak estrogen or nonestrogenic in vitro, were administered as presumptive positive and negative controls, respectively. Controls received the vehicle (ethanol) in tap water. In study 1, rats were treated from days 1-22 after births in studies 2 and 3, the mothers were treated for approximately 8-9 weeks, spanning a 2-week period before mating throughout gestation and 22 days after giving birth. With the exception of DES, treatment generally had no major adverse effect or body weight: in most instances, treated animals were heavier than controls at day 22 and at days 90-95. Exposure to OP, OPP, or BBP at a concentration of 1000 micrograms/1 resulted in a small (5-13%) but significant (p < 0.01 or p < 0.0001) reduction in mean testicular size in studies 2 and 3, an effect that was still evident when testicular weight was expressed relative to body, weight or kidney weight. The effect of OPP is attributed to its metabolism in vivo to OP. DES exposure caused similar reductions in testicular size but also caused reductions in body weight, kidney weight, and litter size. Ventral prostate weight was reduced significantly in DES-treated rats and to minor extent in OP-treated rats. Comparable but more minor effects of treatment with DES or OP on testicular size were observed in study 1. None of the treatments had any adverse effect on testicular morphology or on the cross-sectional area of the lumen or seminiferous epithelium at stages VII-VIII of the spermatogenic cycle, but DES, OP, and BBP caused reductions of 10-21% (p < 0.05 to p < 0.001) in daily sperm production. Humans are exposed to phthalates, such as BBP, and to alkylphenol polyethoxylates, such as OP, but to what extent is unknown. More detailed studies are warranted to assess the possible risk to the development of the human testis from exposure to these and other environmental estrogens. ImagesFigure 1.Figure 2.Figure 3. AFigure 3. BFigure 3. CFigure 3. DFigure 4.
Late effects of early nutritional manipulations.

Effects of early neonatal interventions on metabolic parameters later in life (s.c. late effects) were studied in rats using two models; namely, (a) the effects of premature weaning and (b) the effects of "dietary" manipulations during the suckling period (s.c. small vs. large litters). (a) Premature weaning of rats caused an earlier degeneration of spermiogenesis and elevated plasma cholesterol levels in adult animals when compared to levels found in animals weaned 12 days later (on day 30 after birth). In adult rats, radioiodine uptake in thyroid glands was lower in the group weaned prematurely. Premature weaning was followed by a decrease of corticosterone production in adrenal glands in adult animals; in female adult prematurely weaned rats, an elevated response of adrenal cortex to stressors was observed. Several other studies explored the "immediate" effects of early, premature weaning. (b) Early exposure to high fat diet evoked a hypercholesterolaemic response in adulthood following brief exposure to HF diet. Rats from litters reduced to 3 or 4 pups per mother on postnatal day 3 exhibited 2 days later plasma levels of cholesterol higher than in rats raised in large litters of 8 or 14. The difference between small and large litters was preserved for the whole lifespan of the animals. In adulthood, rats from small litters were fatter and had higher levels of plasma cholesterol and insulin. Other studies suggester that early dietary experience may regulate the pattern of drug metabolism in adult life. An inhibition of diurnal plasma corticosterone variation was found in rats overfed during the neonatal period and an increased stimulation of lipolysis by norepinephrine and lipogenesis by insulin was demonstrated in neonatally underfed rats. Interesting studies were reported in longitudinally studies in children: at the age of 9-12 year breast-fed children (for more than 6 months) had the highest cholesterol levels; on the other hand significantly increased levels of APO B, Apo A1, ATH index and Apo/B Apo A1 quotient (p < 0.05) were found in the nonbreast-fed group (27 references).
Density Dependence and Cooperation: Theory and a Test with Bacteria

Although cooperative systems can persist in nature despite the potential for exploitation by noncooperators, it is often observed that small changes in population demography can tip the balance of selective forces for or against cooperation. Here we consider the role of population density in the context of microbial cooperation. First, we account for conflicting results from recent studies by demonstrating theoretically that: (1) for public goods cooperation, higher densities are relatively unfavorable for cooperation; (2) in contrast, for self-restraint—type cooperation, higher densities can be either favorable or unfavorable for cooperation, depending on the details of the system. We then test our predictions concerning public goods cooperation using strains of the pathogenic bacterium Pseudomonas aeruginosa that produce variable levels of a public good—iron-scavenging siderophore molecules. As predicted, we found that the relative fitness of cheats (under-producers) was greatest at higher population densities. Furthermore, as assumed by theory, we show that this occurs because cheats are better able to exploit the cooperative siderophore production of other cells when they are physically closer to them.
Computational Prediction Models for Early Detection of Risk of Cardiovascular Events Using Mass Spectrometry Data

Early prediction of the risk of cardiovascular events in patients with chest pain is critical in order to provide appropriate medical care for those with positive diagnosis. This paper introduces a computational methodology for predicting such events in the context of robust computerized classification using mass spectrometry data of blood samples collected from patients in emergency departments. We applied the computational theories of statistical and geostatistical linear prediction models to extract effective features of the mass spectra and a simple decision logic to classify disease and control samples for the purpose of early detection. While the statistical and geostatistical techniques provide better results than those obtained from some other methods, the geostatistical approach yields superior results in terms of sensitivity and specificity in various designs of the data set for validation, training, and testing. The proposed computational strategies are very promising for predicting major adverse cardiac events within six months.
Responses to Microbial Challenges by SLAMF Receptors

The SLAMF family (SLAMF) of cell surface glycoproteins is comprised of nine glycoproteins and while SLAMF1, 3, 5, 6, 7, 8, and 9 are self-ligand receptors, SLAMF2 and SLAMF4 interact with each other. Their interactions induce signal transduction networks in trans, thereby shaping immune cell–cell communications. Collectively, these receptors modulate a wide range of functions, such as myeloid cell and lymphocyte development, and T and B cell responses to microbes and parasites. In addition, several SLAMF receptors serve as microbial sensors, which either positively or negatively modulate the function of macrophages, dendritic cells, neutrophils, and NK cells in response to microbial challenges. The SLAMF receptor–microbe interactions contribute both to intracellular microbicidal activity as well as to migration of phagocytes to the site of inflammation. In this review, we describe the current knowledge on how the SLAMF receptors and their specific adapters SLAM-associated protein and EAT-2 regulate innate and adaptive immune responses to microbes.
On the Throughput of Large MIMO Beamforming Systems With Channel Aging

We study the problem of throughput optimization in large multiple-input multiple-output (MIMO) beamforming systems with channel aging, as the number of transmit and receive antennas is increased. We quantify the effective channel coherence time in terms of the intertraining interval, which is the time after which the channel state information needs to be reestimated to avoid loss in performance due to outdated channel estimates. Conventional wisdom suggests that the coherence time of large MIMO systems should decrease with increasing number of antennas, because the system has a large number of independently varying channel coefficients. On the contrary, we show that the effective channel coherence time increases with the number of antennas. We optimize the throughput with respect to the symbol and pilot energies, the number of antennas, frame duration, and target SNR. This analysis brings out the important fact that the effective channel coherence time critically depends on the underlying signaling scheme, and not only on the temporal correlation coefficient of the wireless channel.
Antibacterial and Antifungal Activities of Ethanol Extracts of Halimium halimifolium , Cistus salviifolius and Cistus monspeliensis

The objective of this study was to evaluate antimicrobial and antifungal activities of crude extracts from leaves and flower of Halimium halimifolium, and compared with those of Cistus salviifolius and Cistus monspeliensis. The tested plants (leaves and flowers) were extracted with ethanol, the activities were screened against three Gram-positive (Listeria monocytogenes, Bacillus subtilis and staphylococcus aureus), three Gram-negative bacteria (Salmonella enteric, Pseudomonas aeruginosa and Escherichia coli), and two pathogenic fungi (Candida albicans and Aspergillus niger). The efficacy of these extracts was tested against those microorganisms through a disc-diffusion method employing 15 μL of each sample per paper discs (6 mm in diameter). Comparable results were carried out using Gentamicin and Amphotericin as standard antibiotics. Ethanol extracts of different parts of plant exhibited good activity against all microorganisms tested. The inhibition zone measured ranged from 10 to 26 mm against all the bacteria and 8 to 20 mm against fungal strains. The minimum inhibitory and bactericidal concentrations (MIC and MBC) values against Staphylococcus aureus ranged from 1.562 to 12.5 mg. mL and 3.125 to 25 mg. mL respectively. The Cistus salviifolius leaves had the most potent bactericidal activity. On the other hand, Candida albicans and Aspergillus Niger were the least susceptible microorganisms to all Cistus extracts. In the present work, the antimicrobial potential of ethanol extracts of leaves and flower of Halimium halimifolium, Cistus salviifolius and Cistus monspeliensis is demonstrated. The high levels of antibacterial activities of have been detected, indicating that this plant may serve as an excellent source of natural antibacterial for disease prevention.
[2D and 3D speckle tracking echocardiography: clinical application].

WSTĘP Wizualna ocena zaburzeń kurczliwości to jedno z trudniejszych zagadnień echokardiograficznych, wymagające dużego doświadczenia. Półilościowa ocena kurczliwości związana bywa z różnicami w interpretacji między ekspertami oraz ze zmiennością interpretacji nawet przez tego samego echokardiografistę. Krokiem ku obiektywizacji oceny regionalnej funkcji skurczowej jest wprowadzenie technik ilościowych, pozwalających na analizę odkształcenia (strain) i tempa odkształcenia (strain rate). Parametry te można oceniać za pomocą echokardiografii [tkankowa echokardiografia doplerowska (TDE), technika śledzenia markerów akustycznych (STE)], sonomikrometrii, tomografii komputerowej i rezonansu magnetycznego (MRI) z opcją znakowania [1]. Odkształcenie wyrażane jest w procentach i określa zmianę odległości między dwoma stałymi punktami tkanki mięśniowej w różnych okresach cyklu pracy serca w stosunku do ich położenia wyjściowego. Odkształcenie podłużne i okrężne przyjmują wartości ujemne, gdy dwa punkty zbliżają się do siebie, lub dodatnie, gdy oddalają się od siebie. Natomiast odkształcenie poprzeczne przyjmuje wartości dodatnie, gdy dwa punkty zbliżają się do siebie, lub ujemne, gdy oddalają się od siebie (ryc. 1). Tempo odkształcenia jest wyrażane natomiast jako odwrotność sekundy (s–1) i stanowi różnicę prędkości dwóch punktów w badanym obszarze zainteresowania podzieloną przez odległość między tymi punktami (ryc. 2).
Good intentions and received wisdom are not good enough: the need for controlled trials in public health

In the 1970s Archie Cochrane noted that many healthcare procedures and forms of organisation lacked evidence of effectiveness and efficiency, and argued for improved methods of evaluation, moving from clinical opinion and observation to randomised controlled trials (RCTs). His arguments gradually became accepted in medicine, but there has been considerable resistance among policymakers and researchers to their application to social and public health interventions. This essay argues that opposition to RCTs in public health is often based on a false distinction between healthcare and community settings, and sometimes on a misunderstanding of the principles of RCTs in health care. It suggests that just as in medicine, good intentions and received wisdom are not a sufficient basis for making public policy and allocating public funds for social or health improvement.
Long-term survival following bacteremia or fungemia.

OBJECTIVE To delineate long-term survival after an episode of bacteremia or fungemia and risk factors for mortality. DESIGN Cohort study. SETTING A 900-bed university hospital in Israel. PATIENTS Study group comprising 1991 patients 18 years of age or older in whom bacteremia or fungemia were detected between March 1988 and October 1992, and a control group comprising 1991 inpatients without any infectious diseases, matched for age, sex, department, date of admission, and underlying disorders. INTERVENTIONS None. MEASUREMENTS Interval from the date of the first positive blood culture (study group) or from date of the identical hospital day (in the matched control patient) to the date of death as recorded in the Israeli National Population registry or, if alive, to June 1, 1994. RESULTS The median age of patients was 72 years. In the study group, the mortality rate was 26% at 1 month, 43% at 6 months, 48% at 1 year, and 63% at 4 years, and the median survival was 16.2 months. In the control group, the mortality rate was 7% at 1 month, 27% at 1 year, and 42% at 4 years, and the median survival was greater than 75 months (P < .001). Factors significantly and independently associated with mortality in bacteremic patients were functional class (median survival, 0.5 month in bedridden patients), septic shock (median survival, 0.2 month), serum albumin (median survival, 1.1 months in the lowest quartile), serum creatinine (median survival, 2.9 months in the highest quartile), age (median survival, 2.9 months in the highest quartile [age > 80 years]), inappropriate empirical antibiotic treatment (median survival, 4.9 months), nosocomial infection (median survival, 9.6 months), and malignancy (median survival, 2.4 months). CONCLUSIONS Bacteremia is associated with high short-term mortality, but also a sign of severely curtailed long-term prognosis, especially in patients with low functional capacity, low serum albumin, high serum creatinine, nosocomial infections, malignancy, inappropriate antimicrobial treatment, and septic shock and in elderly patients.
Intra-Operative Tissue Oxygen Tension Is Increased by Local Insufflation of Humidified-Warm CO2 during Open Abdominal Surgery in a Rat Model

Introduction Maintenance of high tissue oxygenation (PtO2) is recommended during surgery because PtO2 is highly predictive of surgical site infection and colonic anastomotic leakage. However, surgical site perfusion is often sub-optimal, creating an obstructive hurdle for traditional, systemically applied therapies to maintain or increase surgical site PtO2. This research tested the hypothesis that insufflation of humidified-warm CO2 into the abdominal cavity would increase sub-peritoneal PtO2 during open abdominal surgery. Materials and Methods 15 Wistar rats underwent laparotomy under general anesthesia. Three sets of randomized cross-over experiments were conducted in which the abdominal cavity was subjected to alternating exposure to 1) humidified-warm CO2 & ambient air; 2) humidified-warm CO2 & dry-cold CO2; and 3) dry-cold CO2 & ambient air. Sub-peritoneal PtO2 and tissue temperature were measured with a polarographic oxygen probe. Results Upon insufflation of humidified-warm CO2, PtO2 increased by 29.8 mmHg (SD 13.3; p<0.001), or 96.6% (SD 51.9), and tissue temperature by 3.0°C (SD 1.7 p<0.001), in comparison with exposure to ambient air. Smaller, but significant, increases in PtO2 were seen in experiments 2 and 3. Tissue temperature decreased upon exposure to dry-cold CO2 compared with ambient air (-1.4°C, SD 0.5, p = 0.001). Conclusions In a rat model, insufflation of humidified-warm CO2 into the abdominal cavity during open abdominal surgery causes an immediate and potentially clinically significant increase in PtO2. The effect is an additive result of the delivery of CO2 and avoidance of evaporative cooling via the delivery of the CO2 gas humidified at body temperature.
An approach based on the concept of use case to produce dynamic object-oriented specifications

Presents an approach based on the concept of "use case" to support the requirements engineering process. The proposed approach assists the analyst in producing dynamic object-oriented requirements specifications. The approach is "domain expert-oriented" in the sense that the domain expert can actively participate during the requirements acquisition activity by identifying and by describing the use cases. A formal technique using Petri nets is also proposed during the requirements acquisition activity in order to make the domain expert's requirements as complete and as unambiguous as possible. During the requirements conceptualization activity, the explanation of how some parts of dynamic requirements specifications can be produced from the formalized use cases is presented.