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1.
Front Res Metr Anal ; 9: 1336190, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694235

RESUMEN

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.

2.
BMC Cardiovasc Disord ; 22(1): 532, 2022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36476214

RESUMEN

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.


Asunto(s)
Índices de Eritrocitos , Insuficiencia Cardíaca , Anciano , Femenino , Humanos , Masculino , Eritrocitos , Insuficiencia Cardíaca/diagnóstico
3.
Caspian J Intern Med ; 12(1): 59-64, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33680399

RESUMEN

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.

4.
J Theor Biol ; 470: 76-89, 2019 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-30858064

RESUMEN

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.


Asunto(s)
Astrocitos/metabolismo , Comunicación Celular/fisiología , Modelos Neurológicos , Red Nerviosa/metabolismo , Neuronas/metabolismo , Animales , Teoría del Juego , Humanos
5.
Curr Hypertens Rev ; 15(1): 70-75, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30246644

RESUMEN

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.


Asunto(s)
Presión Arterial , Ritmo Circadiano , Hipertensión Inducida en el Embarazo/etiología , Preeclampsia/etiología , Segundo Trimestre del Embarazo , Adulto , Monitoreo Ambulatorio de la Presión Arterial , Femenino , Humanos , Hipertensión Inducida en el Embarazo/diagnóstico , Hipertensión Inducida en el Embarazo/fisiopatología , Irán , Preeclampsia/diagnóstico , Preeclampsia/fisiopatología , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Adulto Joven
6.
Nat Mater ; 16(1): 94-100, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27798622

RESUMEN

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.

7.
Int J Trichology ; 8(3): 130-4, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27625565

RESUMEN

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.

8.
Sci Rep ; 6: 23956, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-27050160

RESUMEN

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.

9.
Open Ophthalmol J ; 10: 17-21, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27014382

RESUMEN

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.

10.
Nat Nanotechnol ; 11(4): 352-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26727198

RESUMEN

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.

11.
Nat Commun ; 6: 8958, 2015 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-26643048

RESUMEN

Manipulating magnetism by electric current is of great interest for both fundamental and technological reasons. Much effort has been dedicated to spin-orbit torques (SOTs) in metallic structures, while quantitative investigation of analogous phenomena in magnetic insulators remains challenging due to their low electrical conductivity. Here we address this challenge by exploiting the interaction of light with magnetic order, to directly measure SOTs in both metallic and insulating structures. The equivalency of optical and transport measurements is established by investigating a heavy-metal/ferromagnetic-metal device (Ta/CoFeB/MgO). Subsequently, SOTs are measured optically in the contrasting case of a magnetic-insulator/heavy-metal (YIG/Pt) heterostructure, where analogous transport measurements are not viable. We observe a large anti-damping torque in the YIG/Pt system, revealing its promise for spintronic device applications. Moreover, our results demonstrate that SOT physics is directly accessible by optical means in a range of materials, where transport measurements may not be possible.

12.
Nano Lett ; 15(12): 7905-12, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26524388

RESUMEN

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 ∼ 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.

13.
Open Ophthalmol J ; 9: 149-55, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26535072

RESUMEN

PURPOSE: There is conflicting evidence whether components of metabolic syndrome (MetS) increase or decrease the risk of primary open-angle glaucoma (POAG). The aim of the present study was to determine the association between metabolic syndrome and primary open-angle glaucoma. METHODS: A total of 200 participants comprising 100 controls and 100 patients with POAG documented by clinical tests and examined by an experienced ophthalmologist using standard ophthalmologic equipment were included in the study. MetS was defined and based on ATP III criteria and POAG was defined by the criteria of the International Society of Geographic and Epidemiological Ophthalmology (ISGEO). The data were entered into the SPSS software and analyzed. RESULTS: The prevalence of MetS in the glaucoma group was 53% in comparison to 38% in the control group (p=0.037). MetS was associated with an increased odds ratio for an IOP higher than 21 mmHg (OR: 1.72; 95% CI 1.03-2.79; p=0.034). The mean IOP was 24.91±4.29 mmHg in the patients without MetS, and 27.23±4.81 mmHg in those with MetS (p=0.027). The mean values of CCT were 603.64±63.16 µm in MetS patients and 579.27±72.87 µm in controls (p=0.018). CONCLUSION: Data showed an increased prevalence of components of metabolic syndrome in patients with glaucoma. The mechanisms underlying these associations need to be established in future studies. Our results support the recommendation that patients with metabolic syndrome undergo regular ophthalmological exams to monitor for the onset or progression of glaucoma.

14.
J Res Med Sci ; 20(5): 465-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26487875

RESUMEN

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.

15.
J Pathog ; 2015: 540271, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26421191

RESUMEN

Background. Helicobacter pylori is highly adapted to the gastric environment where it lives within or beneath the gastric mucous layer. The aim of this study was to evaluate whether the addition of N-acetyl cysteine to the treatment regimen of H. pylori infection would affect eradication rates of the disease. Methods. A total of 79 H. pylori positive patients were randomized to two therapeutic groups. Both groups received a 14-day course of three-drug regimen including amoxicillin/clarithromycin/omeprazole. Experimental group (38 subjects) received NAC, and control group (41 subjects) received placebo, besides three-drug regimen. H. pylori eradication was evaluated by urea breath test at least 4 weeks after the cessation of therapy. Results. The rate of H. pylori eradication was 72.9% and 60.9% in experimental and control groups, respectively (P = 0.005). By logistic regression modeling, female gender (OR 3.68, 95% CI: 1.06-5.79; P = 0.040) and treatment including NAC (OR 1.88, 95% CI: 0.68-3.15; P = 0.021) were independent factors associated with H. pylori eradication. Conclusion. The results of the present study show that NAC has an additive effect on the eradication rates of H. pylori obtained with three-drug regimen and appears to be a promising means of eradicating H. pylori infection.

16.
Indian J Crit Care Med ; 19(7): 422-4, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26180437

RESUMEN

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.

17.
J Pathog ; 2015: 152767, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26770828

RESUMEN

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.

18.
Nano Lett ; 14(9): 5423-9, 2014 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-25158276

RESUMEN

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.

19.
Iran Red Crescent Med J ; 16(6): e18026, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25068054

RESUMEN

BACKGROUND: Revealing data on the role of vitamin D and calcium supplementation in bone health has led some to suggest that vitamin D and calcium treatment could also play a role in protecting bone against microgravity-induced mineral loss. OBJECTIVES: The aim of the present study was to investigate the effects of vitamin D and calcium administration on microscopic and densitometric changes of rat femur in a Microgravity Simulator Model. MATERIALS AND METHODS: After designing a Microgravity Simulator Model, 14 rats were placed in the cages as follows: seven rats as osteoporosis group and seven rats received oral supplement of calcium/vitamin D as the treatment group. Animals were sacrificed after eight weeks and then both femurs were removed. Bone mineral density was measured for one femur from each animal, and morphologic studies were evaluated for the contralateral femur. RESULTS: Bone mineral density of the whole femur in the treatment group was significantly higher than the osteoporosis group (0.168 ± 0.005 vs. 0.153 ± 0.006, P = 0.003). Also, bone mineral content of the whole femur was significantly higher in treatment group (0.415 ± 0.016 vs. 0.372 ± 0.019, P = 0.003). However, resorption eroded surface percentage was higher in the osteoporosis group (18.86 ± 3.71% vs. 9.71 ± 1.61%, P = 0.002). CONCLUSIONS: According to the results of this study, vitamin D and calcium administration might have protective effects against microgravity-induced mineral loss in a Rat Microgravity Simulator Model.

20.
Nano Lett ; 14(6): 3459-65, 2014 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-24844837

RESUMEN

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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