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Diabetic striatopathy (DS) is a rare central nervous system complication of diabetes mellitus, characterized mainly by non-ketotic hyperglycemia and lateralized involuntary movements. Patients with diabetic striatopathy manifested solely by subacute cognitive decline were rarely reported. In this paper, we report a patient with DS who presented solely with subacute cognitive decline without involuntary movements, and cranial CT showed bilateral high density in the basal ganglia. In contrast, SWI showed microhemorrhages in the right caudate nucleus head. After one week of treatment, including glycemic control, the patient showed significant improvement in cognitive function, while a repeat cranial CT showed improved hyperdensity in the right basal ganglia region. 1 month later, at telephone follow-up, the patient's symptoms did not recur.
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Corea , Disfunción Cognitiva , Diabetes Mellitus , Discinesias , Humanos , Corea/etiología , Discinesias/etiología , Cuerpo Estriado , Disfunción Cognitiva/complicacionesRESUMEN
Monolayer phosphorene has outstanding spintronic properties including a nanosecond spin lifetime, and micrometer spin relaxation length, combined with excellent mechanical flexibility, making it rather attractive in low-dimensional flexible spintronic devices. However, knowledge on the spin-transport properties of phosphorene under mechanical strain is currently very limited. Here, we study the transport properties of the spin-polarized photocurrent in the flexible Ni-phosphorene-Ni photodetector, which is driven by the photogalvanic effect (PGE) under mechanical tension stress and bending. Broadband PGE photocurrent is generated at zero bias under the illumination of linearly polarized light due to the broken inversion symmetry of the photodetector. Remarkable spin-transport performances including the fully spin-polarized photocurrent, perfect spin-valve effect, and enhanced pure spin current are generated in a broad visible range by applying appropriate mechanical tension stress or bending. Our results indicate that the PGE-driven phosphorene-based photodetector has promising applications in flexible and low-power spintronic devices.
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Fully spin-polarized current and negative differential resistance (NDR) are two important electronic transport properties for spintronic nanodevices based on two-dimensional materials. Here, we describe both the electric and optical tuning of the spin-polarized electronic transport properties of the indium triphosphide (InP3) monolayer, which is doped with Ge atoms, by using quantum transport calculations. The spin degeneration of the InP3 monolayer is lifted due to the doping of Ge atoms. By applying a small bias voltage, a fully spin-polarized current can be obtained along both the armchair and zigzag directions. Moreover, a remarkable NDR is observed for the current along the zigzag direction, which shows a huge peak-to-valley ratio of 3.1 × 103, while in the armchair direction, a lower peak-to-valley ratio of 5.5 is obtained. Alternatively, a fully spin-polarized photocurrent can also be generated under the illumination of linearly-polarized light by tuning either the photon energy or the polarization angle.
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Understanding the electrical properties of defect-free nanowires with different structures and their responses under deformation are essential for design and applications of nanodevices and strain engineering. In this study, defect-free zinc-blende- and wurtzite-structured InAs nanowires were grown using molecular beam epitaxy, and individual nanowires with different structures and orientations were carefully selected and their electrical properties and electromechanical responses were investigated using an electrical probing system inside a transmission electron microscope. Through our careful experimental design and detailed analyses, we uncovered several extraordinary physical phenomena, such as the electromechanical characteristics are dominated by the nanowire orientation, rather than its crystal structure. Our results provide critical insights into different responses induced by deformation of InAs with different structures, which is important for nanowire-based devices.
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OBJECTIVE: To observe the clinical efficacy of lesion removal, bone grafting, fusion, and external fixation in the treatment of late-stage wrist tuberculosis. METHODS: From October 2015 to May 2019, 25 patients with late-stage wrist tuberculosis were treated using lesion removal, bone grafting, fusion, and external fixation. Among these patients, there were 14 males and 11 females, aged from 40 to 74 years old, with an average age of (60.72±8.45) years old. The duration of the disease ranged from 5 to 24 months, with an average of (11.52±7.61) months. There were 11 cases of left wrist tuberculosis and 14 cases of right wrist tuberculosis, with 5 cases accompanied by sinus formation. Postoperative regular anti-tuberculosis treatment was continued. Visual analogue score (VAS), inflammatory indicators, Gartland-Werley wrist function score, and upper limb function score were observed before and after treatment. RESULTS: All 25 patients were followed up for ranging from 12 to 36 months with an average of (19.7±6.3) months. At the latest follow-up, all wounds were healed satisfactorily, and there was no recurrence of tuberculosis or infection. VAS at one week before operation and three months after operation were (5.16±1.14) score and (1.68±0.80) score respectively. One week before operation and three months after operation, erythrocyte sedimentation rate (ESR) was (44.20±20.56) mm·h-1 and (14.44±1.14) mm·h-1, and C-reactive protein (CRP) was (12.37±7.95) mg·L-1 and (4.3±3.37) mg·L-1. The differences in all three data sets were statistically significant (P<0.01). According to Gartland-Werley wrist function scoring, the scores at one week before operation and one year after operation were (21.32±3.44) and (14.96±1.37) respectively, showed a statistically significant difference (P<0.01). According to the upper limb function score (disabilities of the arm, shoulder, and hand, DASH), the score was (70.52±7.95) at one week before operation and(28.84±2.30) at one year after operation. The difference was statistically significant (P<0.01). At the latest follow-up, no patient had a recurrence of tuberculosis. CONCLUSION: The short-term clinical efficacy of treating wrist tuberculosis with lesion removal, bone grafting, fusion, and external fixation is satisfactory.
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Fusión Vertebral , Tuberculosis de la Columna Vertebral , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Adulto , Tuberculosis de la Columna Vertebral/cirugía , Muñeca/cirugía , Trasplante Óseo , Vértebras Torácicas/cirugía , Vértebras Lumbares , Resultado del Tratamiento , Extremidad Superior , Estudios RetrospectivosRESUMEN
Atherosclerosis (AS) is a chronic inflammatory disease resulting from dysregulated lipid metabolism, constituting the pathophysiological foundation of cardiovascular and cerebrovascular diseases. AS has a high incidence rate and mortality rate worldwide. As such, traditional Chinese medicine (TCM) has been widely used recently due to its stable therapeutic effect and high safety. Ganoderma lucidum polysaccharides (GLP) are the main active ingredients of Ganoderma lucidum, a Chinese herbal medicine. Research has also shown that GLP has anti-inflammatory and antioxidant properties, regulates gut microbiota, improves blood glucose and lipid levels, and inhibits obesity. Most of the current research on GLP anti-AS is focused on animal models. Thus, its clinical application remains to be discovered. In this review, we combine relevant research results and start with the pathogenesis and risk factors of GLP on AS, proving that GLP can prevent and treat AS, providing a scientific basis and reference for the future prevention and treatment of AS with GLP.
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Intervertebral disc degeneration (IVDD) is a common degenerative disease which is closely related to low back pain (LBP) and brings huge economic and social burdens. In this study, we explored the therapeutic effects of Homoplantaginin (Hom) for IVDD due to its convincing anti-inflammatory and antioxidant functions. TNF-α was used to simulate the inflammatory environment for nucleus pulposus (NP) cells in vitro. We verified that Hom could alleviate the TNF-α-induced inflammation and disturbance of ECM homeostasis through blocking the NF-κB/MAPK signaling pathways. Subsequently, we screened the binding targets of Hom and confirmed that Hom could directly bind to TAK1 and inhibit its phosphorylation to down-regulate the inflammation-related pathways. The therapeutic effects of Hom on IVDD were further validated through a needle puncture rat model in vivo. Overall, Hom was a promising small molecule for IVDD early intervention, possessing huge clinical translational value.
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Degeneración del Disco Intervertebral , Quinasas Quinasa Quinasa PAM , FN-kappa B , Animales , Humanos , Masculino , Ratas , Células Cultivadas , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Quinasas Quinasa Quinasa PAM/antagonistas & inhibidores , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , FN-kappa B/metabolismo , FN-kappa B/antagonistas & inhibidores , Núcleo Pulposo/metabolismo , Núcleo Pulposo/efectos de los fármacos , Núcleo Pulposo/patología , Unión Proteica/fisiología , Unión Proteica/efectos de los fármacos , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Short-beak and dwarf syndrome (SBDS) is caused by infection with novel goose parvovirus (NGPV), which leads to intestinal dysbiosis, developmental delay, short beak, lameness, and paralysis in ducks and is the cause of skeletal health problems. NGPV infection can cause intestinal microbial disturbances, but it is still unclear whether the intestinal microbiota affects the pathogenicity of NGPV. Here, the effects of intestinal microbiota on NGPV-induced SBDS in Cherry Valley ducks were assessed by establishing a duck model for gut microflora depletion/reestablishment through antibiotics (ABX) treatment/fecal microbiota transplanted (FMT). By measuring body weight, beak length, beak width and tarsal length, we found that SBDS clinical symptoms were alleviated in ducks treated with ABX, but not in FMT ducks. Next, we conducted a comprehensive analysis of bone metabolism, gut barrier integrity, and inflammation levels using quantitative real-time PCR (qPCR), enzyme linked immunosorbent assay (ELISA), biochemical analysis and histological analysis. The results showed that ABX treatment improved bone quality reduced bone resorption, mitigated tissue lesions, protected intestinal barrier integrity, and inhibited systemic inflammation in NGPV-infected ducks. Moreover, cecal microflora composition and short-chain fatty acids (SCFAs) production were examined by bacterial 16S rRNA sequencing and gas chromatography. The results revealed that ABX treatment mitigated the decreased abundance of Firmicutes and Bacteroidota in NGPV-infected ducks, as well as increased SCFAs production. Furthermore, ABX treatment reduced the mucosa-associated lymphoid tissue lymphoma translocation protein 1 (Malt1) and nuclear factor κB (NF-κB) expression, which are correlated with systemic inflammation in SBDS ducks. These findings suggested that intestinal microflora depletion alleviated NGPV-induced SBDS by maintaining intestinal homeostasis, inhibiting inflammatory response and alleviating bone resorption. These results provide evidence for the pivotal role of intestinal microbiota in the process of SBDS and contribute a theoretical basis for the feasibility of microecological preparation as a method to control SBDS.
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Patos , Microbioma Gastrointestinal , Infecciones por Parvoviridae , Parvovirinae , Enfermedades de las Aves de Corral , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Enfermedades de las Aves de Corral/virología , Enfermedades de las Aves de Corral/microbiología , Infecciones por Parvoviridae/veterinaria , Infecciones por Parvoviridae/virología , Parvovirinae/genética , Parvovirinae/fisiología , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Trasplante de Microbiota Fecal/veterinariaRESUMEN
All-nitride Josephson junctions are being actively explored for applications in superconducting quantum chips because of their unique advantages including their antioxidant chemical stability and high crystal quality. However, the theoretical research on their microstructure mechanism that determines transport properties is still absent, especially on the defects. In this paper, we apply the first principles and non-equilibrium Green's function to calculate the electrical transport characteristics of the yellow preset model. It is first revealed that the N-vacancy defects play a crucial role in determining the conductivity of the NbN-based Josephson junctions, and demonstrate the importance for the uniformity of vacancy distribution. It is found that the uniform number of vacancies can effectively increase the conductance of Josephson junction, but the position distribution of vacancies has little effect on the conductance. The work clarifies the effect of the N-vacancy defects on the conductivity of the NbN-based Josephson junctions, which offers useful guidance for understanding the microscope mechanism of the NbN-based Josephson junction, thus showing a great prospect in the improvement of the yield of superconducting quantum chips in the future.
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Chemoresistance is the main obstacle in osteosarcoma (OS) treatment; however, the underlying mechanism remains unclear. In this study, it is discovered that DDRGK domain-containing protein 1 (DDRGK1) plays a fundamental role in chemoresistance induced in OS. Bioinformatic and tissue analyses indicate that higher expression of DDRGK1 correlates with advanced tumor stage and poor clinical prognosis of OS. Quantitative proteomic analyses suggest that DDRGK1 plays a critical role in mitochondrial oxidative phosphorylation. DDRGK1 knockout trigger the accumulation of reactive oxygen species (ROS) and attenuate the stability of nuclear factor erythroid-2-related factor 2 (NRF2), a major antioxidant response element. Furthermore, DDRGK1 inhibits ubiquitin-proteasome-mediated degradation of NRF2 via competitive binding to the Kelch-like ECH-associated protein 1 (KEAP1) protein, which recruits NRF2 to CULLIN(CUL3). DDRGK1 knockout attenuates NRF2 stability, contributing to ROS accumulation, which promotes apoptosis and enhanced chemosensitivity to doxorubicin (DOX) and etoposide in cancer cells. Indeed, DDRGK1 knockout significantly enhances osteosarcoma chemosensitivity to DOX in vivo. The combination of DDRGK1 knockdown and DOX treatment provides a promising new avenue for the effective treatment of OS.
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Factor 2 Relacionado con NF-E2 , Osteosarcoma , Humanos , Resistencia a Antineoplásicos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Osteosarcoma/tratamiento farmacológico , Proteómica , Especies Reactivas de Oxígeno/metabolismo , UbiquitinaciónRESUMEN
We report density functional theory analysis of the electronic and quantum transport properties of Bi(2)Se(3) topological insulator, focusing on the helical surface states at the Fermi level E(F). The calculated Dirac point and the tilt angle of the electron spin in the helical states are compared quantitatively with the experimental data. The calculated conductance near E(F) shows a V-shaped spectrum, consistent with STM measurements. The spins in the helical states at E(F) not only tilts out of the two-dimensional plane, they also oscillate with a 3-fold symmetry going around the two-dimensional Brillouin zone. The helical states penetrate into the material bulk, where the first quintuple layer contributes 70% of the helical wave functions.
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Microplastics (MPs) are ubiquitous in various environment compartments, including food. Here, we collected research reports of MPs in food published during 2010-2020, and summarized the analytical methods developed and utilized by researchers (e.g., digestion, separation and identification, as well as related QA/QC measures implemented), the occurrence, and the characteristics of MPs in six kinds of food. The potential effects on biota from exposure to MPs were also reviewed. The results showed that most researchers digested food samples using chemical solutions such as HNO3, H2O2, KOH, or NaOH. FT-IR and Raman spectroscopy were the main technique for identifying MPs, and microscopes were used to count MP particles. The abundances MPs were in the ranges of 0-5860, 2.00-1100, 0-698, 4.00-18.7, 0-5.68 × 104 and 900-3000 particles/kg in beverages, condiments, honey, meat, seafood and vegetables, respectively. The "maximum" annual human intake of MPs from these foods is approximately 1.42 × 105-1.54 × 105 particles/capita, equivalent to the consumption of 50 plastic bags (size: 0.04 mm × 250 mm × 400 mm, density: 0.98 g/cm3) each year. Blue-colored and fiber-shaped MP particles were the most commonly observed in food, predominated by PA, PE, PES, PET and PP types. Toxicity studies indicated that MPs, additives of MPs and adsorbents or microorganisms on the surfaces of MPs were all somewhat toxic to cells or biota. Exposure to MPs may induce oxidative stress, inflammation, neurotoxicity, and reproductive toxicity, and change the structure of intestinal microflora in cells or biota. Therefore, we call for more investigation into the residual, excretion and bioavailability of MPs or related absorbents/additives in biota and humans.
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Microplásticos , Contaminantes Químicos del Agua , Biota , Monitoreo del Ambiente , Humanos , Peróxido de Hidrógeno , Plásticos/toxicidad , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
BACKGROUND: Gunao-Yizhi decoction has the effects of supplementing intelligence, strengthening marrow, resolving phlegm, and reducing turbidity. It is clinically used for the treatment of vascular dementia (VaD). However, there is still a lack of systematic evaluation of its efficacy and safety. This review conducted a systematic review of the current evidence on the efficacy and safety of Gunao-Yizhi decoction combined with donepezil for VaD. METHODS: China National Knowledge Infrastructure (CNKI), Wanfang database (Wanfang), Chinese Science and Technology Periodical Database (VIP), China Biology Medicine disc (CBM), MEDLINE, EMBASE, and Cochrane Library were searched for randomized controlled trials on Gunao-Yizhi decoction combined with donepezil for VaD. RevMan 5.3 software was used for data analysis. RESULTS: Twelve studies were obtained, including 1036 patients. Compared with donepezil alone, meta-analysis showed that Gunao-Yizhi decoction combined with donepezil could improve clinical efficacy, mini-mental state examination (MMSE) score, Hasegawa dementia scale (HDS), increase the level of superoxide dismutase (SOD) in serum, and reduce the level of malonaldehyde dismutas (MDA) in serum. The GRADE system was adopted to evaluate the outcome index. Clinical efficiency and the MMSE score were evaluated as very-low-quality evidence. HDS score, serum SOD level, and serum MDA level were evaluated as low-quality evidence. CONCLUSION: Gunao-Yizhi decoction combined with donepezil has a significant prevalence in the treatment of vascular dementia, with no increase in adverse events. Gunao-Yizhi decoction can be recommended for routine use in the treatment of VaD.
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Demencia Vascular , Medicamentos Herbarios Chinos , Demencia Vascular/tratamiento farmacológico , Donepezilo/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Malondialdehído , Superóxido DismutasaRESUMEN
Numerous studies have demonstrated the ubiquitous of phthalates in materials of food and food packaging, and the effects of regular eating takeaway food for a long time on human health and phthalate exposure levels were not fully investigated. A total of 288 college students who love eating takeaway food were recruited to explore phthalate exposure and oxidative stress, by measuring metabolites of traditional or alternative phthalates and 8-hydroxydeoxyguanosine (8-OHdG, a biomarker of DNA oxidative damage) in their urine samples. Both traditional and alternative phthalates were highly detected. Based on weekly frequency of takeaway eating collecting from questionnaire, the students were divided into four groups including level 1 (L1, < 3 times), level 2 (L2, 3-7 times), level 3 (L3, 8-12 times) and level 4 (L4, > 12 times). The total concentrations of all phthalate metabolites were 42.5-893 ng/mL in all students, which were significantly different among four groups, with the lowest level in L1 (p < 0.05). Checking with the generalized linear model (L1 as the reference), the concentrations of most phthalate metabolites increased 12.0-144% in L2 and L3 compared with those in L1. For each group increase, the concentrations of total metabolites, and metabolites of high and low molecular weight phthalates will increase by 0.156%, 0.128%, and 0.142%, respectively. Besides, levels of 8-OHdG (0.639-33.7 ng/mL) were positively correlated with phthalate daily exposure doses. The each increase of a percentage unit of daily exposure of phthalates, the concentrations of 8-OHdG will increase by 0.258-0.405%. However, levels of 8-OHdG were not significantly different among the four groups. The alternative phthalates have already entered the body of Chinese young people. Our results indicated the regular consumption of takeaway food (e.g., more than three times per week) may increase the chance of exposure to certain phthalates, and may not significantly increase the levels of DNA oxidative damage, unless exposed to other pollutants such as phthalates.
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Contaminantes Ambientales , Ácidos Ftálicos , 8-Hidroxi-2'-Desoxicoguanosina , Adolescente , Biomarcadores/metabolismo , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/metabolismo , Humanos , Estrés Oxidativo , Ácidos Ftálicos/metabolismoRESUMEN
OBJECTIVE: There is no consensus on the optimal timing of postoperative radiotherapy (PORT) for locally advanced esophageal squamous cell carcinoma (ESCC). We aimed to determine whether the timing of PORT affects the long-term prognosis of ESCC, and plotted nomograms to predict survival. METHODS: We retrospectively analyzed 351 ESCC patients who underwent radical surgery and PORT. Receiver operating characteristic curves were used to estimate the optimal cutoff point of the time interval between surgery and PORT. Cox proportional hazards regression was used to identify prognostic predictors. Overall survival (OS) and progression-free survival (PFS) were predicted using nomograms. RESULTS: The median follow-up was 53 months (range: 3-179 months). Compared to early PORT, PORT at >48 days after surgery was associated with better OS (adjusted hazard ratio [HR]: 1.406, pâ¯=â¯0.037) and PFS (adjusted HR: 1.475, pâ¯=â¯0.018). In the chemotherapy subgroup, incorporation of chemotherapy timing into the analysis suggested that 2-4 chemotherapy cycles followed by PORT was the optimal treatment schedule as compared to 0-1 chemotherapy cycle followed by PORT and concurrent chemoradiotherapy (5-year PFS: 65.9% vs. 51.0% vs. 50.1%; pâ¯=â¯0.049). The nomograms for OS and PFS were superior to the TNM classification (concordance indices: 0.721â¯vs. 0.626 and 0.716â¯vs. 0.610, respectively). CONCLUSIONS: Delayed PORT (>48 days) provides better survival benefit than early PORT among ESCC patients. PORT following 2-4 chemotherapy cycles might lead to the best survival rate. The nomogram plotted in this study effectively predicted survival and may help guide treatment.
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Terahertz detection has been highly sought to open a range of cutting-edge applications in biomedical, high-speed communications, astronomy, security screening, and military surveillance. Nonetheless, these ideal prospects are hindered by the difficulties in photodetection featuring self-powered operation at room temperature. Here, this challenge is addressed for the first time by synthesizing the high-quality ZrGeSe with extraordinary quantum properties of Dirac nodal-line semimetal. Benefiting from its high mobility and gapless nature, a metal-ZrGeSe-metal photodetector with broken mirror symmetry allows for a high-efficiency photoelectric conversion assisted by the photo-thermoelectric effect. The designed architecture features ultrahigh sensitivity, excellent ambient stability, and an efficient rectified signal even above 0.26 THz. Maximum responsivity larger than 0.11 A W-1 , response time of 8.3 µs, noise equivalent power (NEP) less than 0.15 nW Hz-1/2 , and demonstrative imaging application are all achieved. The superb performances with a lower dark current and NEP less than 15 pW Hz-1/2 are validated through integrating the van der Waals heterostructure. These results open up an appealing perspective to explore the nontrivial topology of Dirac nodal-line semimetal by devising the peculiar device geometry that allows for a novel roadmap to address targeted terahertz application requirements.
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Emergent topological Dirac semimetals afford fresh pathways for optoelectronics, although device implementation has been elusive to date. Specifically, palladium ditelluride (PdTe2) combines the capabilities provided by its peculiar band structure, with topologically protected electronic states, with advantages related to the occurrence of high-mobility charge carriers and ambient stability. Here, we demonstrate large photogalvanic effects with high anisotropy at terahertz frequency in PdTe2-based devices. A responsivity of 10 A/W and a noise-equivalent power lower than 2 pW/Hz0.5 are achieved at room temperature, validating the suitability of PdTe2-based devices for applications in photosensing, polarization-sensitive detection, and large-area fast imaging. Our findings open opportunities for exploring uncooled and sensitive photoelectronic devices based on topological semimetals, especially in the highly pursuit terahertz band.
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Two-dimensional thermoelectric (TE) materials which have the figure of merit ZT that is greater than 1.5 at room temperature would be highly desirable in energy conversion since the efficiency is competitive to conventional energy conversion techniques. Here, we report that the indium triphosphide (InP3) monolayer shows a large ZT of 1.92 at 300 K, based on the quantum calculations within the ballistic thermal transport region. A remarkably low and isotropic phononic thermal conductivity is found due to the flat lattice vibration modes, which takes a major responsibility for the impressively high ZT at room temperature. Moreover, a large ZT of 1.67 can still be achieved even under a 1% mechanical tension on the lattice. These results suggest that the InP3 monolayer is a promising candidate for low dimensional TE applications.
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Controlling electronic transport through a single-molecule junction is crucial for molecular electronics or spintronics. In magnetic molecular devices, the spin degree-of-freedom can be used to this end since the magnetic properties of the magnetic ion centers fundamentally impact the transport through the molecules. Here we demonstrate that the electron pathway in a single-molecule device can be selected between two molecular orbitals by varying a magnetic field, giving rise to a tunable anisotropic magnetoresistance up to 93%. The unique tunability of the electron pathways is due to the magnetic reorientation of the transition metal center, resulting in a re-hybridization of molecular orbitals. We obtain the tunneling electron pathways by Kondo effect, which manifests either as a peak or a dip line shape. The energy changes of these spin-reorientations are remarkably low and less than one millielectronvolt. The large tunable anisotropic magnetoresistance could be used to control electronic transport in molecular spintronics.
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High polarization sensitivity, suppressed dark current and low energy consumption are all desirable device properties for photodetectors. In this work, we propose phosphorene-based photodetectors that are driven using photogalvanic effects (PGEs). The inversion symmetry of pristine phosphorene is broken using either application of an out-of-plane gate voltage or a heterostructure that is composed of the original phosphorene and blue phosphorene. The potential asymmetry enables PGEs under illumination by polarized light. Quantum transport calculations show that robust photocurrents are indeed generated by PGEs under a zero external bias voltage because of the broken inversion symmetry. These results indicate that the proposed photodetector is self-powered. In addition, the zero bias voltage eliminates the dark currents that are caused by application of an external bias voltage to traditional photodetectors. High polarization sensitivity to both linearly and circularly polarized light can also be realized, with extinction ratios ranging up to 102. The photoresponse of the proposed phosphorene/blue phosphorene heterostructure can be greatly enhanced by gating and is several orders of magnitude higher than that in gated phosphorene.