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A family of wide-band-gap ternary oxide ferromagnetic semiconductor films with high transition metal concentration was prepared. The resistivity of these films can be changed up to four orders of magnitude by varying the composition or the concentration of the oxygen vacancies. Moreover, all these films show common features in electrical transport, i.e., Mott variable range hopping (VRH) in the lower resistivity range, Efros VRH in the middle resistivity range, and “hard gap” resistance in the higher resistivity range. The above phenomena are well understood by considering the relative magnitude of three characterization lengths, i.e., Coulomb screening length, localization length of the carriers, and optimal hopping distance. Furthermore, spin polarization ratio of these magnetic semiconductors was obtained by fitting the experimental results of electrical transport. Therefore, the wide gap oxide ferromagnetic semiconductors with controllable spin-polarized electrical transport are expected to have application in spintronics devices as a spin injection source. [ABSTRACT FROM AUTHOR]

Ge1-xMnx/Ge single-crystal heterojunction diodes with p-type Ge1-xMnx ferromagnetic semiconductor were grown, respectively on Ge substrates of p-type, n-type, and intrinsic semiconductors by molecular beam epitaxy. The I-V curve of the p-Ge0.95Mn0.05/intrinsic-Ge diode can be greatly tuned by a magnetic field, which was indicated by a large positive magnetoresistance. The magnetoresistance shows a peak value of 700% under a +2 V bias voltage around the Curie temperature of 225 K of the Ge0.95Mn0.05 magnetic semiconductor, and it remains as high as 440% at room temperature. The origin of the positive magnetoresistance is discussed. [ABSTRACT FROM AUTHOR]

Transformation of the electrical transport from the Efros and Shklovskii [J. Phys. C 8, L49 (1975)] variable range hopping to the “hard gap” resistance was experimentally observed in a low temperature range as the Fe compositions in Zn1-xFexO1-v ferromagnetic semiconductor films increase. A universal form of the resistance versus temperature, i.e., ρ∝exp[TH/T+(TES/T)1/2], was theoretically established to describe the experimental transport phenomena by taking into account the electron-electron Coulomb interaction, spin-spin exchange interaction, and hard gap energy. The spin polarization ratio, hard gap energy, and ratio of exchange interaction to Coulomb interaction were obtained by fitting the theoretical model to the experimental results. Moreover, the experimental magnetoresistance was also explained by the electrical transport model. [ABSTRACT FROM AUTHOR]

We report the growth and magnetic properties of all-manganite superlattices composed of ultrathin double-exchange ferromagnetic La0.7Sr0.3MnO3 and noncollinear multiferroic TbMnO3 layers. Spontaneous magnetization and hysteresis loops are observed in such superlattices with individual La0.7Sr0.3MnO3 layers as thin as two unit cells, which are accompanied by pronounced exchange bias and enhanced coercivity. Our results indicate substantial interfacial magnetic coupling between spin sublattices in such superlattices, providing a powerful approach towards tailoring the properties of artificial magnetic heterostructures. [ABSTRACT FROM AUTHOR]

An innovative step-feed Anaerobic-(Oxic/Anoxic)"-Membrane Bioreactor [An-(O/A)"-MBR] process was developed to treat synthetic domestic wastewater. Performance of the lab-scale system was investigated at different dissolved oxygen (DO) concentration (0.4-2.4mg/L) in the aerobic tank of the multiple A/O zone. The results showed that, under the conditions imposed, the DO level has little influence on chemical oxygen demand removal and the removal efficiency was more than 94% throughout the operation. However, DO levels have great influence on nitrogen and phosphorus removal. Better nitrification efficiency could be obtained when DO was in the range of 0.8-2.4mg/L; the ammonia removal efficiency was more than 99%. High total nitrogen (TN) and total phosphorus (TP) removal performance can be obtained when DO was in the range of 0.8-1.2mg/L; the average removal efficiency was 74.8 and 71.4%, respectively. In this condition, DO can meet the demand of nitrification and phosphorus uptake simultaneously, and the simultaneous nitrification and denitrification occurred in the aerobic tanks under lower DO concentration. Meanwhile, since the DO circulated from the aerobic tank to the anoxic tank decreased, denitrification was enhanced and the nitrate quantities in the sludge recycle system decreased, resulting in the decrease of carbon substrate competition between denitrification and phosphorus release in the anaerobic zone. Ultimately, the performance of TN and TP removal was enhanced. [ABSTRACT FROM AUTHOR]

Epitaxial single-crystal Ge1-xMnx ferromagnetic-semiconductor films were fabricated on Ge(001) substrates by molecular beam epitaxy. All the samples are ferromagnetic and have strong magnetic anisotropy indicated by different magnetization in plane and out of plane. The electrical transport of the films obeys Efros variable range hopping law in the low temperature range. Interestingly, a negative coefficient of the ordinary Hall effect of p-type carriers was found in the variable range hopping at low temperature. Anomalous Hall effect in Ge0.949Mn0.051 film was observed below the Curie temperature, indicating the carrier-mediated intrinsic ferromagnetism. [ABSTRACT FROM AUTHOR]

(CoxAl1-x)2O3-v oxide magnetic semiconductor films were synthesized by introducing an impurity band in the insulating Al2O3 band gap, and the corresponding granular films were obtained by annealing. For both kinds of films, their electrical transport properties are well described by spin dependent variable range hopping mechanism instead of the usually expected intergrain tunnelling. The magnetoresistance was also discussed. [ABSTRACT FROM AUTHOR]

Co-doped wurtzite ZnO [Zn(1-x)CoxO] thin films have been grown on Al2O3(0001) substrates by using oxygen plasma-assisted molecular beam epitaxy at the low growth temperature of 450 °C. The epitaxial films of Co concentration at 0≤=x≤=0.12 are single crystalline, which were examined by reflection high energy electron diffraction and x-ray diffraction. Both of optical transmission spectrum and in situ. x-ray photoelectron spectroscopy studies confirmed the incorporation of Co2+ cations into wurtzite ZnO lattice. Magnetic measurements revealed that the Zn(1-x)CoxO thin films are ferromagnetic with Curie temperature TC above room temperature, and the ferromagnetism shows intrinsic characteristic [ABSTRACT FROM AUTHOR]

Homogeneous MnxGe1-x ferromagnetic semiconductor films with high Mn concentration were prepared, contrasting with dilute inhomogeneous MnxGe1-x magnetic semiconductors. The saturation magnetization of Mn0.57Ge0.43 films is high, up to 327 emu/cm3 (1.04μB/Mn) at 5 K, and the Curie temperature is about 213 K. The Mn0.57Ge0.43 films show semiconducting resistance, but the magnetoresistance is negligibly small. The anomalous Hall effect was observed below the Curie temperature, which is consistent with the magnetic measurements. The global ferromagnetism was discussed based on s,p-d exchange coupling between the weakly localized s,p hole carriers and the strongly localized d electrons of the Mn atoms. [ABSTRACT FROM AUTHOR]

Patients with deep burns are prone to suffer cicatrix hyperplasia or contracture, leading to problems including dysfunction in limbs, which impacts patients' life quality and makes it difficult for them to return to society. Thereby, the rehabilitation treatment after deep burns is particularly important. Currently, exercise therapy plays an important role in burn rehabilitation, which is mainly based on therapies such as continuous manual assistance training and manual stretching practice to provide patients with physical exercise to limbs and to correct the functional dysfunction of limbs in patients. With the continuous progress in technology, functional training robots have been developed to meet the needs. The emergence of functional training robots saves manpower and provides patients refined and standardized functional exercise treatment. From the aspects of production technology and multi-technology integration, this paper mainly introduces the recent innovation and development of functional training robots and the advantages of the application of functional training robots in the field of burn rehabilitation.

Objective: To understand the epidemiological characteristics of COVID-19 epidemic in Ejina banner, Inner Mongolia, in October 2021 and provide evidence for the improvement of COVID-19 prevention and control. Methods: The information about the time, area and population distributions of COVID-19 cases in Ejina before November 13, 2021 and the gene sequencing result of the isolates were collected for a statistical descriptive analysis. Results: The first COVID-19 case in Ejina occurred on 7 October, 2021. A total of 164 COVID-19 cases were reported from October 19 to November 12. Most cases were distributed in 6 communities in Darahub (156 cases, 95.12%). The result of full gene sequencing of the isolates indicted that the pathogen was Delta variant (B.1.617.2). The male to female ratio of the cases was 1.3∶1. The age of cases ranged from 1 to 85 years, and the cases aged 20-59 years accounted for 78.66%. The main clinical symptoms were sore throat (91 cases, 91.92%), cough (49 cases, 49.49%) and fever (23 cases, 23.23%). Most cases were ordinary ones (81 cases, 49.39%) and mild ones (68 cases, 41.46%). The cases were mainly detected at the isolation points (84 cases, 51.22%) and through population based nucleic acid testing (62 cases, 37.80%). The basic reproduction number ( R 0 ) of COVID-19 was 5.3, the average incubation period was 3.9 days. The local government rapidly started Ⅳ level emergency response and conducted 10 rounds of nucleic acid tests. The transferring of travelers reduced the risk for the further spread of COVID-19 in Ejina. Conclusions: The epidemic of COVID-19 in Ejina characterized by strong transmission, short incubation period, herd susceptibility and case clustering. Delta variant (B.1.617.2) was the pathogen, which might be imported from Zeke port. Comprehensive prevention and control measures, such as closed-loop management and vaccination, should be continued. The successful transferring of the patients and travelers provided evidence for the effective and precise prevention and control of COVID-19 in a routine manner.

Objective: To evaluate the postoperatively hidden blood loss of elderly intertrochanteric fracture patients fixed with combined external fixator, and to explore the correlation between hidden blood loss and age. Methods: A retrospective analysis was conducted on 60 elderly intertrochanteric fracture patients who were admitted to the Department of Orthopedics of Hebei Provincial Hospital from January 2016 to May 2019. All the fractures were fixed with combined external fixators. The patients were divided into two groups according to the age: there were 31 cases in group A (60-80 years old) and 29 cases in group B (≥80 years old). The Gross equation and the Nandler formula were used to evaluate the amount of hidden blood loss based on changes in hematocrit (Hct) at the day preoperatively, 3 days postoperatively and the weight. The data were compared between the two groups by independent-sample t test. Results: The decreased Hct, hemoglobin(Hb) and the dominant blood loss and hidden blood loss in group A and B was 3.4%±1.7%, (13±7) g/L, (25±6) ml, (186±7) ml and 3.8%±1.2%, (13±3) g/L, (24±8) ml, (194±7) ml, respectively. There was no significant differences in the dominant and hidden blood loss between the groups ( t= 0.309, 0.883, both P> 0.05). Conclusion: The age doesn't affect the hidden blood loss in elderly intertrochanteric fracture patients fixed with combined external fixator, which indicated that the operation is safe and reliable for such patients.