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Introduction: Transforaminal lumbar interbody fusion (TLIF) is commonly used in patients with lumbar degenerative disease (LDD). The most commonly used techniques include minimally invasive TLIF (MIS-TLIF) and percutaneous endoscopic TLIF (PE-TLIF). Aim: To compare the safety and clinical effectiveness of PE-TLIF and MIS-TLIF in treating LDD. Material and methods: We screened for related articles in multiple scientific databases, namely, PubMed, Embase, Cochrane Library, Wanfang, VIP, and CINK, and analyzed the relative outcomes. Results: Based on our inclusion criteria, we selected 8 studies for meta-analysis. There are a total of 229 patients who underwent PE-TLIF and 258 patients who underwent MIS-TLIF. MIS-TLIF and PE-TLIF have similar effectiveness in relieving leg pain and improving the Oswestry Disability Index. However, PE-TLIF is superior in relieving back pain. The pooled data of fusion rates, postoperative analgesic, and complication rates are comparable between the 2 groups. The pooled operation and intra-operative fluoroscopic time are both significantly higher in the PE-TLIF group than the MIS-TLIF group. The pooled intra-operative blood loss, incision length, duration from surgery to ambulation, and hospital stay are significantly lower in the PE-TLIF group than the MIS-TLIF group. Most of the endpoints reveal significant heterogeneity. The endpoints of operation time and intra-operative blood loss reveal significant publication bias. Conclusions: Both PE-TLIF and MIS-TLIF are safe and effective interventions for patients with LDD. When compared, although MIS-TLIF results in reduced operative time, less intra-operative blood loss and enhanced post-operative recovery can be achieved by PE-TLIF. [ABSTRACT FROM AUTHOR]

We present a modulation transfer spectroscopy (MTS) configuration based on an acousto-optic modulator by using a variant of the typical double pass structure. One beam is modulated by using an acousto-optic modulator in opposite diffraction order to cancel the carrier frequency shift and produce a modulated pump beam. The line shape performance is investigated theoretically and experimentally. Laser frequency stabilization of the proposed configuration is demonstrated for the 133Cs |62S1/2, F = 4⟩ → |62P3/2, F′ = 5⟩ transition. The Allan deviations, which are measured by using beat note signals and the three-cornered hat method, are 3.6 × 10−11 in an integration time of 100 s and approximately 4 × 10−11 in a longer integration time. [ABSTRACT FROM AUTHOR]

We establish a novel method of controlling the transverse modes of vertical cavity surface emitting lasers (VCSELs) to achieve 1 mW single-fundamental-mode lasing. A dielectric mode filter is installed on top of the VCSEL. The dielectric layer (SiO2) is deposited and patterned to modify the mirror reflectivity across the oxide aperture via antiphase reflections. This mode selection is nondestructive and universally applicable for other structures under single transverse mode. Destructive etching techniques (dry/wet) or epitaxial regrowth are also not required. This method simplifies the preparation process and improves the repeatability of the device. Measurements show that under continuous-wave current injection, the side-mode suppression ratio exceeds 30 dB. [ABSTRACT FROM AUTHOR]

For most pulsed atomic clocks, the Dick effect is one of the main limits to reach its frequency stability limitation due to quantum projection noise. In this paper, we measure the phase noise of the local oscillator in the Ramsey-CPT atomic clock and calculate the Dick effect induced Allan deviation based on a three-level atomic model, which is quite different from typical atomic clocks. We further present a detailed analysis of optimizing the sensitivity function and minimizing the Dick effect by interleaving lock. By optimizing the duty circle of laser pulses, average time during detection and optical intensity of laser beam, the Dick effect induced Allan deviation can be reduced to the level of . [ABSTRACT FROM AUTHOR]

In this paper, stable single-mode operation at high temperatures is produced by the surface-relief-integrated vertical cavity surface emitting laser (VCSEL). The gain-cavity mode detuning technique is employed to realize high operating temperatures for the VCSEL. The surface relief is etched in the centre of the top side as a mode discriminator for the fundamental mode output, and the threshold current minimum is 1.94 mA at high temperatures by the gain-cavity mode detuning technique. Maximum single-fundamental-mode output power of 0.45 mW at 80 °C is obtained, and the side mode suppression ratios (SMSRs) are more than 30 dB with increasing temperature and current, respectively. [ABSTRACT FROM AUTHOR]

We report our studies on an intense source of cold cesium atoms based on a two-dimensional (2D) magneto–optical trap (MOT) with independent axial cooling and pushing. The new-designed source, proposed as 2D-HP MOT, uses hollow laser beams for axial cooling and a thin pushing laser beam to extract a cold atomic beam. With the independent pushing beam, the atomic flux can be substantially optimized. The total atomic flux maximum obtained in the 2D-HP MOT is 4.02 × 1010 atoms/s, increased by 60 percent compared to the traditional 2D+ MOT in our experiment. Moreover, with the pushing power 10 μW and detuning 0Γ, the 2D-HP MOT can generate a rather intense atomic beam with the concomitant light shift suppressed by a factor of 20. The axial velocity distribution of the cold cesium beams centers at 6.8 m/s with an FMHW of about 2.8 m/s. The dependences of the atomic flux on the pushing power and detuning are studied in detail. The experimental results are in good agreement with the theoretical model. [ABSTRACT FROM AUTHOR]

The article presents a study which reported a small molecule-catalyzed asymmetric rearrangement of cyclopropylcarbinyl cations, leading to a series of chiral homoallylic sulfide products with good to excellent yields and enantioselectivities. Topics discussed include reaction development and optimization, screening of substrate scopes, and mechanistic consideration.

Drawing on the job demands-resources (JD-R) model and event system theory (EST), this study constructed a moderated mediating model to investigate the direct effect of career calling on work fatigue, the mediating effect of role overload, and the moderating effect of COVID-19 event disruption in the above relationships. We administered an online questionnaire to 488 Chinese police officers who participated in frontline work to prevent and control the COVID-19 pandemic. The results showed a U-shaped curvilinear relationship of career calling with physical fatigue, mental fatigue, emotional fatigue, and role overload. Moreover, role overload partially mediated these curvilinear relationships. In addition, COVID-19 event disruption positively moderated the direct curvilinear effect of career calling on role overload, physical fatigue, and emotional fatigue, as well as the first stage of the mediating effect in the relationship between career calling and physical, mental, and emotional fatigue through role overload. Furthermore, the direct U-shaped curvilinear effects and the indirect effects were more significant when COVID-19 event disruption was high.

Introduction Preliminary evidence from clinical observations suggests that Tai Chi exercise may offer potential benefits for patients with chronic coronary syndrom (CCS). However, the advantages for CCS patients to practice Tai Chi exercise as rehabilitation have not been rigorously tested and there is a lack of consensus on its benefits. This study aims to develop an innovative Tai Chi Cardiac Rehabilitation Program (TCCRP) for CCS patients and to assess the efficacy, safety and acceptability of the programme.Methods and analysis We propose to conduct a multicentre randomised controlled clinical trial comprising of 150 participants with CCS. The patients will be randomly assigned in a 1:1 ratio into two groups. The intervention group will participate in a supervised TCCRP held three times a week for 3 months. The control group will receive supervised conventional exercise rehabilitation held three times a week for 3 months. The primary and secondary outcomes will be assessed at baseline, 1 month, 3 months after intervention and after an additional 3-month follow-up period. Primary outcome measures will include a score of 36-Item Short Form Survey and Chinese Perceived Stress Scale. The secondary outcome measures will include body composition, cardiopulmonary exercise test, respiratory muscle function, locomotor skills, echocardiogram, New York Heart Association classification, heart rate recovery time and laboratory examination. Other measures also include Seattle Angina Scale, Pittsburgh Sleep Quality Index, Patient Health Questionnaire-9, Generalized Anxiety Disorder-7 and Berg Balance Scale. All adverse events will be recorded and analysed.Ethics and dissemination This study conforms to the principles of the Declaration of Helsinki and relevant ethical guidelines. Ethical approval has been obtained from the Ethics Committee of Chinese People’s Libration Army General Hospital (approval number: S2019-060-02). Findings from this study will be published and presented at conferences for widespread dissemination of the results.Trial registration number NCT03936504.

In-hand manipulation is a fundamental ability for multi-fingered robotic hands that interact with their environments. Owing to the high dimensionality of robotic hands and intermittent contact dynamics, effectively programming a robotic hand for in-hand manipulations is still a challenging problem. To address this challenge, this work employs deep reinforcement learning (DRL) algorithm to learn in-hand manipulations for multi-fingered robotic hands. A reward-shaping method is proposed to assist the learning of in-hand manipulation. The synergy of robotic hand postures is analysed to build a low-dimensional hand posture space. Two additional rewards are designed based on both the analysis of hand synergies and its learning history. The two additional rewards cooperating with an extrinsic reward are used to assist the in-hand manipulation learning. Three value functions are trained jointly with respect to their reward functions. Then they cooperate to optimise a control policy for in-hand manipulation. The reward shaping not only improves the exploration efficiency of the DRL algorithm but also provides a way to incorporate domain knowledge. The performance of the proposed learning method is evaluated with object rotation tasks. Experimental results demonstrated that the proposed learning method enables multi-fingered robotic hands to learn in-hand manipulation effectively.

Purpose: To develop a simple, precise and rapid high-performance liquid chromatographic technique coupled with photodiode array detection (DAD) method for the simultaneous determination of rutin, quercetin, luteolin, genistein, galangin and curcumin in propolis. Ultrasound-assisted extraction was applied to isolate six antioxidant phenolic compounds from propolis samples. Chromatographic separation was performed using an Eclipse XDB-C18 column (150 mm×4.6 mm, 5 μ) bu isocratic elution at 25 °C. The mobile phase consisted of phosphate buffered saline (pH = 4.5) and methanol (40/60, v/v). The flow rate was set at 0.8 ml/min and the effluent was monitored using a DAD set at 260 nm. Results: Excellent linear correlation coefficient was observed in the range of 0.9977 to 0.9997. The reproducibility of the method was 1.58 % (RSD) and accuracy was confirmed with average recovery ranging from 95.71 to 104.26 %. Six antioxidant phenolic compounds in propolis samples were successfully determined within 50 min. Conclusion: The proposed isocratic LC method gave good separation and accurate determination of rutin, quercetin, luteolin, genistein, galangin and curcumin in propolis. The proposed method showed good sensitivity, linearity, repeatability and accuracy. [ABSTRACT FROM AUTHOR]

Pancreatic tumors, with peri-pancreatic main vascular invasion, especially the superior mesenteric vein (SMV) or the portal vein, are very common. In some cases, vascular resection and reconstruction are required for complete resection of pancreatic tumors. However, the optimum surgical method for venous management is controversial. Resection of the SMV without reconstruction during surgery for pancreatic tumors is rarely reported. Here we present the case of a 58-year-old woman with a giant pancreatic mucinous cystadenoma adhering to the SMV, who underwent an en bloc tumor resection, including the main trunk of the SMV and the spleen. No venous reconstruction was performed during surgery. No ischemic changes occurred in the bowel. The presence of several well-developed collateral vessels was shown by 3-dimensional computed tomography examination. The patient had an uneventful postoperative period and was discharged. This case indicated that the main trunk of the SMV can be resected without venous reconstruction if adequate collateralization has formed.

Aim: To examine the impact of body mass index (BMI) on outcomes following pancreatic resection in the Chinese population., Methods: A retrospective cohort study using prospectively collected data was conducted at the Cancer Hospital of the Chinese Academy of Medical Sciences, China National Cancer Center. Individuals who underwent pancreatic resection between January 2004 and December 2013 were identified and included in the study. Persons were classified as having a normal weight if their BMI was < 24 kg/m(2) and overweight/obese if their BMI was ≥ 24 kg/m(2) as defined by the International Life Sciences Institute Focal Point in China. A χ(2) test (for categorical variables) or a t test (for continuous variables) was used to examine the differences in patients' characteristics between normal weight and overweight/obese groups. Multiple logistic regression models were used to assess the associations of postoperative complications, operative difficulty, length of hospital stay, and cost with BMI, adjusting for age, sex, and type of surgery procedures., Results: A total of 362 consecutive patients with data available for BMI calculation underwent pancreatic resection for benign or malignant disease from January 1, 2004 to December 31, 2013. Of the 362 patients, 156 were overweight or obese and 206 were of normal weight. One or more postoperative complications occurred in 35.4% of the patients following pancreatic resection. Among patients who were overweight or obese, 42.9% experienced one or more complications, significantly higher than normal weight (29.6%) individuals (P = 0.0086). Compared with individuals who had normal weight, those with a BMI ≥ 24.0 kg/m(2) had higher delayed gastric emptying (19.9% vs 5.8%, P < 0.0001) and bile leak (7.7% vs 1.9%, P = 0.0068). There were no significant differences seen in pancreatic fistula, gastrointestinal hemorrhage, reoperation, readmission, or other complications. BMI did not show a significant association with intraoperative blood loss, operative time, length of hospital stay, or cost., Conclusion: Higher BMI increases the risk for postoperative complications after pancreatectomy in the Chinese population. The findings require replication in future studies with larger sample sizes.

Aim: To investigate the prognostic value of metastatic lymph node ratio (MLNR) in extrahepatic cholangiocarcinoma (ECC) patients undergoing radical resection., Methods: Seventy-eight patients with ECC were enrolled. Associations between various clinicopathologic factors and prognosis were investigated by Kaplan-Meier analyses. The Cox proportional-hazards model was used for multivariate survival analysis., Results: The overall three- and five-year survival rates were 47.26% and 23.99%, respectively. MLNR of 0, 0-0.2, 0.2-0.5, and > 0.5 corresponded to five-year survival rates of 28.59%, 21.60%, 18.84%, and 10.03%, respectively. Univariate analysis showed that degree of tumor differentiation, lymph node metastasis, MLNR, tumor-node-metastasis (TNM) stage, and margin status were closely associated with postoperative survival in ECC patients (P < 0.05). Multivariate analysis showed that MLNR and TNM stage were independent prognostic factors after pancreaticoduodenectomy (HR = 2.13, 95%CI: 1.45-3.11; P < 0.01; and HR = 1.97, 95%CI: 1.17-3.31; P = 0.01, respectively). The median survival time for MLNR > 0.5, 0.2-0.5, 0-0.2, and 0 was 15 mo, 24 mo, 23 mo, and 35.5 mo, respectively. There were statistical differences in survival time between patients with different MLNR (χ(2) = 15.38; P < 0.01)., Conclusion: MLNR is an independent prognostic factor for ECC patients after radical resection and is useful for predicting postoperative survival.

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that arise from the gastrointestinal tract. In rare cases, these tumors are found in intra-abdominal sites unrelated to the gastrointestinal tract, such as the mesentery, omentum and retroperitoneum. However, pancreatic extra-gastrointestinal stromal tumors are extremely rare, with only 14 previous cases reported. A 61-year-old man with no clinical symptoms had a routine check-up, during which an abdominal mass located in the pancreas tail was detected. Abdominal surgery was performed with resection of the pancreas tail and the spleen, and he was diagnosed with low-risk GISTs. Another 60-year-old man with no clinical symptoms underwent Computed tomography which revealed a well-demarcated tumor, 6 cm in diameter, in the head of the pancreas. He was diagnosed with pancreatic GISTs. Here, we describe two rare cases of pancreatic GISTs and review the cases previously reported in the literature.