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BACKGROUND: Various investigations have specified the role of each RBC indices separately [including hemoglobin (Hb), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and red blood cell distribution width (RDW)] to predict the prognosis of acute heart failure (AHF) patients. However, in the current study, these variables were compared based on accuracy, sensitivity, and specificity to determine the best prognostic factor. METHODS: Of 734 heart failure patients referred to the emergency department, 400 cases were enrolled based on the inclusion and exclusion criteria. Data of them were documented, and patients were followed for one year. Eventually, the association of clinical variables and RBC indices with one-year mortality was explored. RESULTS: The study included 226 (56%) men and 174 (44%) women with a median age of 66 years. Body Mass Index (HR 1.098, p = 0.016), Hb (HR 0.728, p = 0.024), HTC (HR 0.875, p = 0.066), MCHC (HR 0.795, p = 0.037), and RDW-CV (HR 1.174, p = 0.006) were confirmed as predictors of long-term mortality. Despite confirming the predictive role of these variables by ROC curves, their sensitivity and specificity were reported as follows: [72% and 50% for Hb], [75% and 52% for HCT], [88% and 27% for MCHC], and [49% and 81% for RDW]. In addition, stratified groups of patients, based on normal cut-off values obtained from scientific literature, had significantly different survival in Kaplan-Meier analyses. CONCLUSION: Whilst proving the predictive role of Hb, HCT, MCHC, and RDW in AHF patients, the most sensitive measurement was MCHC and the most specific one was RDW; therefore, these variables should be considered for risk stratification purposes of AHF patients in daily clinical practice.
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Índices de Eritrócitos , Insuficiência Cardíaca , Idoso , Feminino , Humanos , Masculino , Eritrócitos , Insuficiência Cardíaca/diagnósticoRESUMO
A neuron is the fundamental unit of the nervous system and the brain, crucial for transducing information in form of trains of electrical pulses known as action potentials. The connection between neurons is through synapses, enabling communication between neurons. This communication link is one of the key elements in processing of information from a neuron to another neuron. The strength of the synapses may vary over time, a phenomenon known as synaptic plasticity. This is the process by which it is believed memory and learning is governed. Recent studies revealed environmental factors affect the strength of synapses, and the way neurons communicate to each other. This poses the question as to what extent the pre- and post- synaptic neurons sense the environmental changes, and in turn adjust their synaptic link. Here, we model the behavior of an interconnected neuronal network in various environmental conditions as a multi-agent system in a game theoretic framework. We focus on a CA1 lattice subfield as an example plastic neuronal network. Our analysis revealed the neuronal network converges to different equilibria depending on the environmental changes. The model well-predicts the behavior of the network compared to a well-known theoretical model of individual neurons.
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Astrócitos/metabolismo , Comunicação Celular/fisiologia , Modelos Neurológicos , Rede Nervosa/metabolismo , Neurônios/metabolismo , Animais , Teoria dos Jogos , HumanosRESUMO
Magnetic topological insulators such as Cr-doped (Bi,Sb)2Te3 provide a platform for the realization of versatile time-reversal symmetry-breaking physics. By constructing heterostructures exhibiting Néel order in an antiferromagnetic CrSb and ferromagnetic order in Cr-doped (Bi,Sb)2Te3, we realize emergent interfacial magnetic phenomena which can be tailored through artificial structural engineering. Through deliberate geometrical design of heterostructures and superlattices, we demonstrate the use of antiferromagnetic exchange coupling in manipulating the magnetic properties of magnetic topological insulators. Proximity effects are shown to induce an interfacial spin texture modulation and establish an effective long-range exchange coupling mediated by antiferromagnetism, which significantly enhances the magnetic ordering temperature in the superlattice. This work provides a new framework on integrating topological insulators with antiferromagnetic materials and unveils new avenues towards dissipationless topological antiferromagnetic spintronics.
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The vertical transport of nonequilibrium charge carriers through semiconductor heterostructures has led to milestones in electronics with the development of the hot-electron transistor. Recently, significant advances have been made with atomically sharp heterostructures implementing various two-dimensional materials. Although graphene-base hot-electron transistors show great promise for electronic switching at high frequencies, they are limited by their low current gain. Here we show that, by choosing MoS2 and HfO2 for the filter barrier interface and using a noncrystalline semiconductor such as ITO for the collector, we can achieve an unprecedentedly high-current gain (α â¼ 0.95) in our hot-electron transistors operating at room temperature. Furthermore, the current gain can be tuned over 2 orders of magnitude with the collector-base voltage albeit this feature currently presents a drawback in the transistor performance metrics such as poor output resistance and poor intrinsic voltage gain. We anticipate our transistors will pave the way toward the realization of novel flexible 2D material-based high-density, low-energy, and high-frequency hot-carrier electronic applications.
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Recent demonstrations of magnetization switching induced by in-plane current in heavy metal/ferromagnetic heterostructures (HMFHs) have drawn great attention to spin torques arising from large spin-orbit coupling (SOC). Given the intrinsic strong SOC, topological insulators (TIs) are expected to be promising candidates for exploring spin-orbit torque (SOT)-related physics. Here we demonstrate experimentally the magnetization switching through giant SOT induced by an in-plane current in a chromium-doped TI bilayer heterostructure. The critical current density required for switching is below 8.9 × 10(4) A cm(-2) at 1.9 K. Moreover, the SOT is calibrated by measuring the effective spin-orbit field using second-harmonic methods. The effective field to current ratio and the spin-Hall angle tangent are almost three orders of magnitude larger than those reported for HMFHs. The giant SOT and efficient current-induced magnetization switching exhibited by the bilayer heterostructure may lead to innovative spintronics applications such as ultralow power dissipation memory and logic devices.
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Strong spin-orbit interaction and time-reversal symmetry in topological insulators enable the spin-momentum locking for the helical surface states. To date, however, there has been little report of direct electrical spin injection/detection in topological insulator. In this Letter, we report the electrical detection of spin-polarized surface states conduction using a Co/Al2O3 ferromagnetic tunneling contact in which the compound topological insulator (Bi0.53Sb0.47)2Te3 was used to achieve low bulk carrier density. Resistance (voltage) hysteresis with the amplitude up to about 10 Ω was observed when sweeping the magnetic field to change the relative orientation between the Co electrode magnetization and the spin polarization of surface states. The two resistance states were reversible by changing the electric current direction, affirming the spin-momentum locking in the topological surface states. Angle-dependent measurement was also performed to further confirm that the abrupt change in the voltage (resistance) was associated with the magnetization switching of the Co electrode. The spin voltage amplitude was quantitatively analyzed to yield an effective spin polarization of 1.02% for the surface states conduction in (Bi0.53Sb0.47)2Te3. Our results show a direct evidence of spin polarization in the topological surface states conduction. It might open up great opportunities to explore energy-efficient spintronic devices based on topological insulators.
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Introducing magnetic order in a topological insulator (TI) breaks time-reversal symmetry of the surface states and can thus yield a variety of interesting physics and promises for novel spintronic devices. To date, however, magnetic effects in TIs have been demonstrated only at temperatures far below those needed for practical applications. In this work, we study the magnetic properties of Bi2Se3 surface states (SS) in the proximity of a high Tc ferrimagnetic insulator (FMI), yttrium iron garnet (YIG or Y3Fe5O12). Proximity-induced butterfly and square-shaped magnetoresistance loops are observed by magneto-transport measurements with out-of-plane and in-plane fields, respectively, and can be correlated with the magnetization of the YIG substrate. More importantly, a magnetic signal from the Bi2Se3 up to 130 K is clearly observed by magneto-optical Kerr effect measurements. Our results demonstrate the proximity-induced TI magnetism at higher temperatures, an important step toward room-temperature application of TI-based spintronic devices.
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It was reported that in some individuals who received postexposure rabies vaccine, clinical features of rabies developed at the shorter time compared to individuals who were exposed, but not received the vaccine, which called "early death" phenomenon. We reported an early death phenomenon in a 67-year-old woman who was bitten by a jackal, although receiving three dose of rabies vaccine. Results show that the immune response to rabies has a dual role, sometimes has a favorable effect on survival but sometimes amplification the disease.
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BACKGROUND: There is limited information on the relationship between metabolic syndrome (MetS) and chronic kidney disease (CKD) in the Iranian population, a group that has a high prevalence of CKD and obesity. The aim of present study was to determine the relationship between MetS and CKD in West of Iran. MATERIALS AND METHODS: A total of 800 subjects aged more than 35 years admitted from 2011 to 2013 were enrolled in the study. MetS was defined based on the Adult Treatment Panel III criteria, and CKD was defined from the Kidney Disease Outcomes Quality Initiative practice guidelines. Waist circumference and body mass index were calculated, as well, blood samples were taken and lipid profile, plasma glucose levels, and serum creatinine were measured. Data were analyzed with SPSS version 17 (SPSS Inc., Chicago, IL, USA). RESULTS: CKD was seen in 14.8% patients with MetS and 8.3% individuals without MetS. MetS was associated with an increased odds ratio (OR) for a glomerular filtration rate <60 ml/min/1.73 m(2) (OR: 1.91; 95% confidence interval [CI]: 1.22-2.99; P = 0.004). Individuals with 2, 3, 4, and 5 components of the MetS had an increased OR for CKD: 2.19 (95% CI: 0.95-3.62), 2.65 (95% CI: 1.03-4.71), 2.86 (95% CI: 1.08-5.53), and 5.03 (95% CI: 1.80-8.57), respectively, compared with individuals with none of the components. CONCLUSION: We found a high prevalence of CKD in patients with MetS compared with the subject without MetS. Our observations raised major clinical and public health concerns in Iran, where both the MetS and kidney diseases are becoming common.
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Although previous preconceived notions discourage authors from asserting their presence in research articles (RAs), recent studies have substantiated that the use of self-mention markers offer a means to establish authorial identity and recognition in a given discipline. Few studies, however, explored specific sections of research articles to uncover how self-mentions function within each section's conventions. Exploring the use of self-mention markers, the present study aimed at comparing the method sections written by native English writers and L-1 Persian writers in the field of psychology. The corpus contained 120 RAs, with each sub-corpora including 60 RAs. The RAs were then examined structurally and functionally. The data were analyzed both quantitatively, using frequency counts and chi-square analyses, and qualitatively through content analysis. The findings indicated a significant difference between English and Persian authors concerning the frequency of self-mentions and the dimension of rhetorical functions; however, the differences in the dimensions of grammatical forms and hedging and boosting were found insignificant. Native English authors were inclined to make more use of self-mentions in their research articles. The findings of the current study can assist EAP and ESP novice researchers in taking cognizance of the conventions of authorial identity in each genre.
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Using a new technique, transient Rayleigh scattering, we show that measurements from a single GaAs/AlGaAs core-shell semiconductor nanowire provide sensitive and detailed information on the time evolution of the density and temperature of the electrons and holes after photoexcitation by an intense laser pulse. Through band filling, band gap renormalization, and plasma screening, the presence of a dense and hot electron-hole plasma directly influences the real and imaginary parts of the complex index of refraction that in turn affects the spectral dependence of the Rayleigh scattering cross-section in well-defined ways. By measuring this spectral dependence as a function of time, we directly determine the thermodynamically independent density and temperature of the electrons and holes as a function of time after pulsed excitation as the carriers thermalize to the lattice temperature. We successfully model the results by including ambipolar transport, recombination, and cooling through optic and acoustic phonon emission that quantify the hole mobility at â¼68,000 cm(2)/V·s, linear decay constant at 380 ps, bimolecular recombination rate at 4.8 × 10(-9) cm(3)/s and the energy-loss rate of plasma due to optical and acoustic phonon emission.
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The internal electronic structures of single semiconductor nanowires can be resolved using photomodulated Rayleigh scattering spectroscopy. The Rayleigh scattering from semiconductor nanowires is strongly polarization sensitive which allows a nearly background-free method for detecting only the light that is scattered from a single nanowire. While the Rayleigh scattering efficiency from a semiconductor nanowire depends on the dielectric contrast, it is relatively featureless as a function of energy. However, if the nanowire is photomodulated using a second pump laser beam, the internal electronic structure can be resolved with extremely high signal-to-noise and spectral resolution. The photomodulated Rayleigh scattering spectra can be understood theoretically as a first derivative of the scattering efficiency that results from a modulation of the band gap and depends sensitively on the nanowire diameter. Fits to spectral lineshapes provide both the band structure and the diameter of individual GaAs and InP nanowires under investigation.
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Highly strained GaAs/GaP nanowires of excellent optical quality were grown with 50 nm diameter GaAs cores and 25 nm GaP shells. Photoluminescence from these nanowires is observed at energies dramatically shifted from the unstrained GaAs free exciton emission energy by 260 meV. Using Raman scattering, we show that it is possible to separately measure the degree of compressive and shear strain of the GaAs core and show that the Raman response of the GaP shell is consistent with tensile strain. The Raman and photoluminescence measurement are both on good agreement with 8 band k.p calculations. This result opens up new possibilities for engineering the electronic properties of the nanowires for optimal design of one-dimensional nanodevices by controlling the strain of the core and shell by varying the nanowire geometry.
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Arsenicais/química , Gálio/química , Teste de Materiais/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Fosfinas/química , Análise Espectral Raman/métodos , Módulo de Elasticidade , Elétrons , Conformação Molecular , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Estresse Mecânico , Resistência à TraçãoRESUMO
BACKGROUND: White blood cell count (WBC) is one of the objective parameters of systemic inflammation. The aim of present study was to evaluate the relationship between WBC count and metabolic syndrome. METHODS: In this study on Lor population in Borujerd province (West of Iran), from 2011 to 2013, 800 persons were enrolled. MetS was defined based on ATP III criteria. Differences among the quartiles of WBC were examined by one-way analysis of variance. RESULTS: Only 14.7% did not have any of the five components and 43% of all subjects had metabolic syndrome. The means of WBC count in MetS group were significantly higher than the control group (p<0.0001). In subjects without any MetS components, the means of WBC was 5.321 /µL, and it was 5.664, 5.714, 5.961, 6.302, and 6.572 /µL in subjects with 1, 2, 3, 4, and 5 components, respectively. These differences show a significant increasing trend (p<0.0001). CONCLUSION: WBC count was associated with clustered components of metabolic syndrome. It seems that WBC counts could be considered as a predictive factor for metabolic syndrome in preventive medicine.
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BACKGROUND: Preeclampsia is a global burden with 10 million incidences annually and 210 daily deaths worldwide. Diagnosis is mainly based on the features following full presentation. OBJECTIVE: This study explored whether early pregnancy circadian changes of ambulatory blood pressure monitoring (ABPM) could predict preeclampsia and hypertension. METHODS: In a prospective study, 294 pregnant women who were referred to Sarem Women's Hospital, Iran were recruited. Systolic, diastolic and mean arterial pressures (MAP) were recorded (diurnally and nocturnally) in each trimester. Dipping was defined as a minimum 10% decrease in blood pressure. RESULTS: Of the 251 women who completed the study, 25 percent (n=63) experienced blunted MAP dipping during sleep phases in the second trimester. Eighty-nine percent (n=56) experienced hypertensive disorder in the third trimester, one-third of which experienced preeclampsia. Of the women with normal MAP dipping (n=188), 5 percent (n=10) had gestational hypertension and 1 percent (n=2) became preeclamptic. (P<0.0001). CONCLUSION: This study clearly demonstrated blunted blood pressure dipping overnight during the second trimester which is a strong predictor of forthcoming pregnancy-induced hypertension and preeclampsia. A scoring system was developed to predict hypertensive disorder and it was significantly correlated with preeclampsia occurrence.
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Pressão Arterial , Ritmo Circadiano , Hipertensão Induzida pela Gravidez/etiologia , Pré-Eclâmpsia/etiologia , Segundo Trimestre da Gravidez , Adulto , Monitorização Ambulatorial da Pressão Arterial , Feminino , Humanos , Hipertensão Induzida pela Gravidez/diagnóstico , Hipertensão Induzida pela Gravidez/fisiopatologia , Irã (Geográfico) , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/fisiopatologia , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Adulto JovemRESUMO
PURPOSE: An important cause of avoidable childhood blindness is retinopathy of prematurity (ROP) in countries with high human development index and also in some emerging economies countries. To date, no research have been conducted on analyzing data of ROP prevalence in Babol, and this is the first research performed on ROP in this area. METHODS: All VLBW babies who referred to Babol ophthalmology center over the seven years, from February 2007 to December 2013 were enrolled in this descriptive cross-sectional research. A team of researchers recorded patients' information completely in check lists. A single experienced ophthalmologist performed ophthalmologic examination of patients. RESULT: The incidence of ROP of any stage in Babol was determined to be 306 (45%) of all babies enrolled in this study. In present study, key risk factors of ROP were low gestational age, oxygen therapy more than five days and low birth weight. CONCLUSION: The findings of current study demonstrate that the main risk factors of developing ROP in newborns are multiple gestation, low birth weight, oxygen therapy for more than five day. Therefore, the progression of ROP to blindness will be prevented by a high index of suspicion, suitable screening, prompt diagnosis, and early treatment.
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BACKGROUND: Hirsutism is one of the most important diseases that lead women to refer to dermatology clinic. Hyperprolactinemia is one of the causes of hirsutism. The aim of this study was to determine prolactin (PRL) levels in hirsute women. MATERIALS AND METHODS: In this cross-sectional study, hirsute patients were evaluated. For all of the patients, 2 or 3 days after mense starting, hormone level tests were performed, and 200 patients that had not polycystic ovary syndrome enrolled to the study. A questionnaire of history and physical examination were performed. Data have been analyzed with SPSS version 21. RESULTS: Hyperprolactinemia were seen in 25 patients (12.5%). There was no significant relation between marital statuses, galactorrhoea, positive family history, and infertility with hyperprolactinemia. But significant relation was seen between irregular mense and hyperprolactinemia. CONCLUSION: Although hyperprolactinemia is the rare cause of hirsutism, the prevalence of hyperprolactinemia was high in our study. Thus, PRL level in hirsute patients should be evaluate.
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Current-induced spin-orbit torques (SOTs) in structurally asymmetric multilayers have been used to efficiently manipulate magnetization. In a structure with vertical symmetry breaking, a damping-like SOT can deterministically switch a perpendicular magnet, provided an in-plane magnetic field is applied. Recently, it has been further demonstrated that the in-plane magnetic field can be eliminated by introducing a new type of perpendicular field-like SOT via incorporating a lateral structural asymmetry into the device. Typically, however, when a current is applied to such devices with combined vertical and lateral asymmetries, both the perpendicular field-like torque and the damping-like torque coexist, hence jointly affecting the magnetization switching behavior. Here, we study perpendicular magnetization switching driven by the combination of the perpendicular field-like and the damping-like SOTs, which exhibits deterministic switching mediated through domain wall propagation. It is demonstrated that the role of the damping-like SOT in the deterministic switching is highly dependent on the magnetization direction in the domain wall. By contrast, the perpendicular field-like SOT is solely determined by the relative orientation between the lateral structural asymmetry and the current direction, regardless of the magnetization direction in the domain wall. The experimental results further the understanding of SOTs-induced switching, with implications for spintronic devices.
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Electric-field manipulation of magnetic order has proved of both fundamental and technological importance in spintronic devices. So far, electric-field control of ferromagnetism, magnetization and magnetic anisotropy has been explored in various magnetic materials, but the efficient electric-field control of spin-orbit torque (SOT) still remains elusive. Here, we report the effective electric-field control of a giant SOT in a Cr-doped topological insulator (TI) thin film using a top-gate field-effect transistor structure. The SOT strength can be modulated by a factor of four within the accessible gate voltage range, and it shows strong correlation with the spin-polarized surface current in the film. Furthermore, we demonstrate the magnetization switching by scanning gate voltage with constant current and in-plane magnetic field applied in the film. The effective electric-field control of SOT and the giant spin-torque efficiency in Cr-doped TI may lead to the development of energy-efficient gate-controlled spin-torque devices compatible with modern field-effect semiconductor technologies.
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Introduction. In recent years, the number of contact lens wearers has dramatically increased in Iran, particularly in youngsters. The purpose of current study was to assess the clinical presentation and antibiotic susceptibility of contact lens related microbial keratitis in Ahvaz, southwest of Iran. Methodology. A cross-sectional investigation of 26 patients (33 eyes) with contact lens induced corneal ulcers who were admitted to Imam Khomeini Hospital, Ahwaz City, from June 2012 to June 2013 was done. In order to study microbial culture and susceptibility of corneal ulcers, all of them were scraped. Results. Eight samples were reported as sterile. Pseudomonas aeruginosa (80%) in positive cultures was the most widely recognized causative organism isolated. This is followed by Staphylococcus aureus 12% and Enterobacter 8%. The results showed that 84% of the microorganism cases were sensitive to ciprofloxacin, while imipenem, meropenem, and ceftazidime were the second most effective antibiotics (76%). Conclusion. Results of current study show the importance of referring all contact lens wearers with suspected corneal infection to ophthalmologists for more cure. The corneal scraping culture and contact lens solution should be performed to guide antibiotic therapy.