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Objective To assess the long‐term clinical efficacy of TiRobot‐assisted percutaneous cannulated screw fixation in the treatment of femoral neck fractures. Methods This retrospective study included 50 patients with unilateral femoral neck fractures who were treated with TiRobot‐assisted percutaneous cannulated screw fixation from September 2017 to May 2018. After at least 2 years of follow‐up, the results of treatment, including operation duration, frequency of fluoroscopy use, intraoperative bleeding, hospital stay, medical expense, screw placement accuracy, rate of fracture healing and necrosis of the femoral head, and Harris hip scores at the last follow up, were recorded and compared with those of 83 matched patients who underwent conventional manual positioning surgery. Results The TiRobot group had longer operation duration (83.3 ± 31.2 min vs 44.1 ± 14.8 min) and higher medical expenses (28,407.1 ± 7498.0 yuan vs 22,672.3 ± 4130.3 yuan) than the conventional group. The TiRobot group had significantly less intraoperative bleeding (11.3 ± 7.3 mL vs 51.6 ± 40.4 mL) and shorter hospital stay (8.6 ± 2.8 days vs 11.1 ± 3.41 days) than the conventional group. Screw parallelism (1.32° ± 1.85° vs 2.54° ± 2.99° on anteroposterior radiograph; 1.42° ± 2.25° vs 3.09° ± 3.63° on lateral radiograph) and distance between screws (58.44 ± 10.52 mm vs 39.69 ± 12.17 mm) were significantly improved. No significant difference was found between the two groups in terms of the use of fluoroscopy (40.1 ± 28.5 times vs 38.6 ± 21.0 times) and Harris hip scores at the last follow‐up (93.2 ± 10.3 points vs 88.4 ± 11.9 points). Two cannulated screws penetrated the femoral head during manual insertion in the conventional group but not in the TiRobot group. The rate of nonunion and necrosis of the femoral head in the TiRobot group was reduced compared with that in the conventional group (0 vs 7.2%; 6.0% vs 24.1%). Conclusion TiRobot‐assisted percutaneous cannulated screw fixation of femoral neck fractures is accurate and minimally invasive and helps in reducing late complications, particularly necrosis of the femoral head and nonunion of fractures., TiRobot‐assisted percutaneous cannulated screw fixation of femoral neck fractures is accurate and minimally invasive, and helps in reducing late complications, particularly necrosis of the femoral head and nonunion of fracture.

Birds have a wide range of activities in the natural environment, and there are a lot of uncontrollable factors. Therefore, recording the neural signals and behavior data of birds in natural state transition is a major difficulty in the progress of neuroscience. At present, most neuroscience fields usually use wired EEG acquisition equipment, but due to its large size and heavy weight, it is not suitable for small animals, especially birds, to record neural and behavior data in natural state. In order to solve the above problems, we designed a wearable neuro-signal recording system in this study, which can synchronously record the neuro-signal and attitude data of birds in flight. The core processor of this system uses STM32 series high performance single-chip computer, and its peripheral components are described as follows: (1) 8-channel neural signal acquisition module based on AD1299; (2) GPS global positioning module; (3) Attitude measurement unit; (4) TF card storage module. The total weight of the system is about 20 g and the volume is about 27 mm x 25 mm x 15 mm. Finally, the neural signals and attitude data of the pigeons moving freely on the ground and in the sky were collected using the system we designed. The results showed that the system can not only stably record neural signals, attitude information and position information at the same time, but also does not affect their normal flight. The system has a good application prospect. Researchers can use it to record and analyze the neural signals of experimental animals, especially birds in free movement and even flight. Our work provides a portable and feasible experimental tool for further study of the neural mechanism of the brain in more complex environment.

By the end of 2017, a total of 110,872 people living with HIV (PLWH) had been diagnosed in Sichuan, including 42,496 AIDS patients, making Sichuan one of the provinces heavily affected by the HIV/AIDS epidemic. The male/female ratio was 2.8:1; the 20–49 age group accounted for 68.5% of infections; and the Han ethnic majority accounted for 68.1% and the Yi ethnic minority accounted for 30.3% of the total cases. PLWH have a wide range of occupations, with farmers, unemployed, and rural migrant workers taking up the majority. Transmission by injection drug use accounted for the majority of cases until 2010, with sexual transmission rapidly expanding in the last decade. By the end of 2017, nearly 79,000 PLWH were receiving antiretroviral treatment in Sichuan province. Mortality greatly declined in recent years among those who received treatment. The number of HIV-related deaths surpassed 5000 in 2017. A comprehensive surveillance network has been set up composed of routine screening, case reporting, sentinel surveillance, specific epidemiological investigation, estimation of the HIV epidemic, and analysis of the incidence rate in different risk groups. Education activities targeting different groups have been carried out from provincial level to prefecture level and communities. Free antiretroviral treatment during the past decade has reduced the mortality rate among PLWH and has improved the quality of their life. Tailored behavioral interventions were implemented to effectively change high-risk behaviors among key populations. Prevention of mother-to-child transmission (PMTCT) has covered all 21 prefectures and 181 counties. A comprehensive prevention and treatment system that takes the community as its basis, health departments its mainstay, and professional institutes its backbone, with the coordination of security, civil administration and education, and the general public have been established. Remarkable progress has been made, but a great challenge lies ahead to control HIV sexual transmission, particularly in minorities.

Antiretroviral therapy (ART) has been introduced recently and has significantly impacted morbidity and mortality, but can also engender drug resistance. To identify the prevalence of HIV-1 drug resistance (HIVDR) among patients with antiretroviral therapy failure in Sichuan during the period from 2010 to 2016, we carried out a longitudinal study in Sichuan, a province with the highest HIV/AIDS prevalence in China. The data and blood samples were collected from HIV/AIDS patients who received ART for more than half a year. Overall 5,512 sequences were completed from 7,059 ART-failure patients, and 2,499 individuals were identified as drug resistant. Among those with HIVDR mutations identified, 25.37% were against non-nucleoside reverse transcriptase inhibitors (NNRTIs), and 1.60% was against nucleoside reverse transcriptase inhibitors (NRTIs). NRTI-resistant drugs were mainly lamivudine (3TC) (57.77%) and emtricitabine (FTC), while NNRTI-resistant drugs were mainly nevirapine (NVP) (91.13%) and efavirenz (EFV) (72.81%). The most common recombination subtypes of HIV-1 in sequenced samples were CRF07_BC (circulating recombinant form, CRF) (41.42%), followed by CRF01_AE (40.77%). Moreover, drug resistance rate increased with the prolongation of treatment time (χ2 = 14.758, P < 0.05). The overall prevalence of acquired drug resistance in HIV-1 infected patients in Sichuan was 5.47%, which has remained relatively stable from 2010 to 2016. HIV-1 CRF01_AE and CRF07_BC subtypes were the main epidemic strains, and the possibility of resistance was higher in CRF01_AE subtypes. The current study highlights the importance of acquired drug resistance surveillance over a long period.

To evaluate the attitudes towards informing senile patients about the diagnosis among Chinese clinicians, patients and their relatives, and explore the factors restricting senior citizens from implementing their right of informed consent independently, a cross-sectional study was conducted in Beijing in June 2013. 100 clinicians, 250 competent inpatients and their closest relatives chosen by stratified random sampling method were measured by a questionnaire anonymously. There were 78 doctors, 203 patients and 218 relatives who responded, and 60.6% of the patients were over 65 years old. As with the young and middle-aged, almost all senile patients desired to learn about their condition. However, to avoid dispute or other troubles, 52.9% of medical staff tended to inform the family members first, and 9.5% of relatives were reluctant to disclose all the information to senile patients for fear of embarrassment or other undesirable negative effects. So increasing the communication skills training for clinicians, abandoning the rule of family members’ consent for competent patients and publicising the positive effects of informed consent are the key measures to safeguard senile patients’ rights in China.

This study describes the current situation and projects dynamic trends for HIV prevalence in a highly endemic area of China, Liangshan Prefecture, Sichuan Province. Epidemiological, behavioral, and population census data from multiple sources were analyzed to extract input for an Asian Epidemic Model (AEM). Fitting curves to historical trends in HIV prevalence were used as a baseline, and future intervention scenarios were explored using the AEM. For 2007, modeled data suggested approximately 0.5% adult HIV prevalence in Liangshan, with an estimated 17,450 people living with HIV/AIDS and 3,400 new infections. With current high risk behaviors, the model predicts that adult prevalence will rise to 1.5% by 2020. Increased condom use and clean needle exchange among injection drug users (IDUs) have slowed the epidemic. The source of new HIV infections will change from a preponderance of IDU-related infections in 2007 (65.9%) to a mixed epidemic in 2020 (general population heterosexuals 45.2%, IDU 38.6%, homosexual transmission between men 12.7%, female sex workers and their clients 3.5%). We anticipate rising prevalence, stable incidence, and higher representation of sexual transmission over time. Prevention investments should target specific interventions toward sub-groups at highest risk, given that both IDUs and men who have sex with men will likely represent a majority of cases and serve as a bridge population.

China's commitment to implementing established and emerging HIV/AIDS prevention and control strategies has led to substantial gains in terms of access to antiretroviral treatment and prevention services, but the evolving and multifaceted HIV/AIDS epidemic in China highlights the challenges of maintaining that response. This study presents modeling results exploring the potential impact of HIV vaccines in the Chinese context at varying efficacy and coverage rates, while further exploring the potential implications of vaccination programs aimed at reaching populations at highest risk of HIV infection. A preventive HIV vaccine would add a powerful tool to China's response, even if not 100% efficacious or available to the full population.

Three community-based surveys recruited 4,310 injection drug users (IDUs) in China from 2004 to 2006. Of the participants, 54.4% were ≤ 3-year new IDUs; 63.9% reported injecting more than two times daily; 31.5% shared needles in the last six months; 37.4% shared equipments in the last month; 30.2% reported their regular sex partners injected drugs; and 23.5% had commercial sex, with 52.2% reporting no condom use during last sex. The risky injection practices (sharing needles/equipments and high injection frequency) were less frequent among new IDUs, emphasizing that effective prevention needs to identify and intervene with IDUs early on. The study's limitations are noted.

This paper presents the theoretical development of a revised optimal control pilot model (ROCM) based the modified optimal control model (MOCM) of human operator developed by Davidson and Schmidt. An algorithm designed for easy implantation in current computer simulation and simulator fidelity analysis is presented. Example results based upon the analysis of a tracking task using a basic dynamics system is compared with the results of the ROCM and the results of the MOCM. The pilot frequency responses and root mean square obtained with the ROM are shown to more favorably to the measured experimental results than the MOCM in the pilot's frequency range of interest. The ROCM is not only consonant with the appropriate physical essence of the pilot, but also possess' the advantages of the MOCM.

The rare-earth doped strontium aluminate phosphors SrxCa4-xAl14O25:Eu2+,Dy3+（x＝0，0.8，1.6，2.4，3.2，4） were synthesized by a high temperature solid-state reaction method. The X-ray diffraction studies show that phase of the phosphors is orthorhombic Sr4Al14O25 for x4O7 for x > 2.4. The results indicate that the phase structure of the samples changes from Sr4Al14O25 to CaAl4O7 when the value of x changes from 0 to 4. In addition, a blue shift was found in the emission spectra due to the change in nature of the Eu2+ surroundings. The decay characteristics show that the phosphor samples with different Ca2+ contents have different afterglow time, and the afterglow time also changes with the value of x. The measurement of thermoluminescence reveals that the trap depth of the phosphor samples with different Ca2+ contents is different. The samples with deeper traps have longer afterglow time.

Photoactivating oxygen dangling bonds on tapered micro/nanofibers enhances monolayer photoluminescence quantum yields., Although monolayer transition metal dichalcogenides (TMDs) have direct bandgaps, the low room-temperature photoluminescence quantum yields (QYs), especially under high pump intensity, limit their practical applications. Here, we use a simple photoactivation method to enhance the room-temperature QYs of monolayer MoS2 grown on to silica micro/nanofibers by more than two orders of magnitude in a wide pump dynamic range. The high-density oxygen dangling bonds released from the tapered micro/nanofiber surface are the key to this strong enhancement of QYs. As the pump intensity increases from 10−1 to 104 W cm−2, our photoactivated monolayer MoS2 exhibits QYs from ~30 to 1% while maintaining high environmental stability, allowing direct lasing with greatly reduced thresholds down to 5 W cm−2. Our strategy can be extended to other TMDs and offers a solution to the most challenging problem toward the realization of efficient and stable light emitters at room temperature based on these atomically thin materials.