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AbstractIntroductionMaterial and methodsResultsConclusionsThis study aims to assess the safety and clinical efficacy of percutaneous splenic embolization (PSE) and splenectomy as approaches to treating cases of traumatic splenic rupture (TSR).Eligible articles published throughout August 2023 were identified. Endpoints compared between PSE and splenectomy patient groups included operative time, intraoperative hemorrhage, duration of hospitalization, postoperative complication rates, and measures of immune function.Thirteen studies, involving 474 and 520 patients in the PSE and splenectomy groups respectively, were incorporated into this meta-analysis. As compared to the splenectomy group, individuals treated via PSE exhibited a significant reduction in pooled operative time (p < 0.00001) and hospitalization duration (p < 0.00001), with corresponding reductions in rates of intraoperative hemorrhage (p < 0.00001), total complications (p < 0.0001), incisional infection (p < 0.0001), ileus (p = 0.0004), and abdominal infection (p = 0.02). The immune status of these PSE group patients was also improved, as evidenced by significantly higher pooled CD4+ (30 days), CD4+/CD8+ (30 days), and CD3+ (30 days) values (p < 0.0001, 0.0001, and 0.0001, respectively).Compared to splenectomy, PSE-based TSR treatment can significantly reduce operative time, rate of postoperative complications, and incidence of intraoperative hemorrhage, while improving post-procedural immune functionality. [ABSTRACT FROM AUTHOR]

Background and aim: The latest Barcelona Clinic Liver Cancer (BCLC) staging system suggests considering surgery in patients with resectable BCLC stage 0/A hepatocellular carcinoma (HCC) and clinically significant portal hypertension (CSPH). This study aimed to evaluate the safety and short- and long-term outcomes of laparoscopic hepatectomy for BCLC stage 0/A HCC patients with CSPH. Methods: We retrospectively reviewed the medical records of 647 HCC patients in BCLC stage 0/A who were treated at five centers between January 2010 and January 2019. Among these patients, 434 underwent laparoscopic hepatectomy, and 213 underwent open hepatectomy. We used Kaplan–Meier analysis to compare the overall survival (OS) rate and recurrence-free survival (RFS) rate between patients with and without CSPH before and after propensity score matching (PSM). Multivariate Cox regression analysis was performed to identify prognostic factors for BCLC stage 0/A patients, and subgroup analyses were also conducted. Results: Among the 434 patients who underwent laparoscopic hepatectomy, 186 had CSPH and 248 did not. The Kaplan–Meier analysis showed that the OS and RFS rates were significantly worse in the CSPH group before and after PSM. Multivariate Cox regression analyses identified CSPH as a prognostic factor for poor OS and RFS after laparoscopic hepatectomy. However, CSPH patients treated laparoscopically had a better short- and long-term prognosis than those treated with open surgery. Conclusions: CSPH has a negative impact on the prognosis of BCLC stage 0/A HCC patients after laparoscopic hepatectomy. Laparoscopic hepatectomy is still recommended for treatment, but careful patient selection is essential. [ABSTRACT FROM AUTHOR]

To explore the clinical and molecular characteristics, diagnosis, and treatment of early-onset autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV) in Chinese patients. A retrospective, interventional case series was assembled from three ADNIV patients. The three ADNIV cases harbored de novo CAPN5 mutations (p.Arg289Trp and p.Leu73Val). The ages of onset ranged from 11 months to 2 years. All the cases presented with vitreous opacity and subretinal inflammatory exudations. During the postoperative follow-up, all the patients manifested with exaggerated postoperative inflammatory responses. An intravitreal Ozurdex injection could not effectively control ocular inflammation in ADNIV. Laser spots after panretinal photocoagulation were partly visible. Two de novo CAPN5 mutations (p.Leu73Val and p.Arg289Trp) could cause early-onset ADNIV. Panretinal photocoagulation during vitrectomy and an intravitreal Ozurdex injection could not significantly stop the progression of subretinal exudations and ocular inflammation in early-onset ADNIV patients. [ABSTRACT FROM AUTHOR]

Background and Aim: Clinical work has revealed that hepatectomy for resectable ruptured hepatocellular carcinoma (rHCC) has a relatively high percentage of positive resection margins found in postoperative pathology. It is necessary to evaluate the risk factors associated with R1 resection in patients undergoing hepatectomy for rHCC. Methods: A total of 408 patients with resectable rHCC originating from three centers undergoing surgery from January 2012 to January 2020 were consecutively enrolled in the study to study the prognostic impact of R1 resection using Kaplan–Meier plotting of survival curves. One center with 280 served as the training group, and the other two centers served as the validation group. Multivariate logistic regression analysis screened for variables affecting R1 and developed prediction models, and the models were tested in the validation cohort using the receiver operating characteristic curves (ROC) and calibration curves. Results: The prognosis of rHCC patients with positive cut margins was worse than that of patients with R0 resection. Risk factors for R1 resection were tumor max length (OR = 2.668 [1.161–6.131]), microvascular invasion (MVI) (OR = 3.655 [1.766–7.566]), times of hepatic inflow occlusion (1/0:OR = 2.213 [1.113–4.399]; 2/0:OR = 5.723 [2.010–8.289]) and timing of hepatectomy (OR = 5.284 [2.394–9.661]), using tumor max length, times of HIO, and timing of hepatectomy to construct the nomogram, the area under the curve of the model was 0.810 (0.781–0.842) and 0.782 (0.752–0.805) in the training and validation groups, respectively, and the calibration curve of the model was basically on the 45° line. Conclusions: This study constructs a clinical model to predict R1 resection after hepatectomy for resectable rHCC, which can be used to better plan perioperative strategies for the incidence of R1 resection during hepatectomy. [ABSTRACT FROM AUTHOR]

Background: Epidural clonidine improves analgesia but may induce adverse effects in labor. Objective: To evaluate the efficacy and safety of epidural clonidine as local anesthetics (LA) adjuvant by continuous infusion or patient‐controlled epidural analgesia (PCEA) in labor. Search Strategy: PubMed, Embase, Web of Science, and CENTRAL were searched from inception to May 10, 2022 without language restriction; references of the retrieved studies were hand searched. Selection Criteria: Randomized controlled trials (RCTs) comparing epidural LA with and without clonidine using continuous infusion or PCEA in labor were included. Data Collection and Analysis: A random effects model was used to pool the data on analgesia and adverse effects. Main Results: Eight RCTs were included. Clonidine did not reduce the incidence of parturients requiring additional epidural boluses but reduced LA consumption and pain scores without increasing adverse effects, except for a higher incidence of instrumental delivery when clonidine was combined with LA and opioid (risk ratio 2.38, 95% confidence interval 1.26–4.50). Clonidine offered similar analgesia to opioids but had reduced opioid‐related adverse effects. Trial sequential analysis showed that the evidence was insufficient. Conclusions: Epidural clonidine by continuous infusion or PCEA does not increase significant adverse effects and offers similar analgesia to opioids in labor. PROSPERO registration no. CRD42022306565. Synopsis: Epidural clonidine by continuous infusion or patient‐controlled analgesia provides analgesia similar to opioids without significantly increasing maternal and neonatal adverse effects in labor. [ABSTRACT FROM AUTHOR]

Warm-sector heavy rainfall (WR), shear-line heavy rainfall (SR), and frontal heavy rainfall (FR) are three types of rainfall that frequently occur during the pre-summer rainy season in south China. In this research, we investigated the differences in microphysical characteristics of heavy rainfall events during the period of 10-15 May 2022 based on the combined observations from 11 S-band polarimetric radars in south China. The conclusions are as follows: (1) WR has the highest radar echo top height, the strongest radar echo at all altitudes, the highest lightning density, and the most active ice-phase process, which suggests that the convection is the most vigorous in the WR, moderate in the FR, and the weakest in the SR. (2) Three types of rainfall are all marine-type precipitation, the massweighted mean diameter (Dm, mm) and the intercept parameter (Nw, mm-1m-3) of the raindrops in the WR are the largest. (3) The WR possesses the highest proportion of graupel compared with the FR and SR, and stronger updrafts and more abundant water vapor supply may lead to larger raindrops during the melting and collision-coalescence processes. (4) Over all the heights, liquid and ice water content in the WR are higher than those in the SR and FR, the ratio of ice to liquid water content in the WR is as high as 27% when ZH exceeds 50 dBZ, definitely higher than that in the SR and FR, indicating that the active ice-phase process existing in the WR is conducive to the formation of heavy rainfall. [ABSTRACT FROM AUTHOR]

A temperature sensor based on composite multicavity Fabry-Perot interferometers (FPIs) and a sensitivity-enhanced differential phase demodulation method is proposed and demonstrated. The structure was fabricated by partially filled polydimethylsiloxane (PDMS) into a segment of hollow-core fiber (HCF) which is spliced with a single-mode fiber (SMF). In this structure, composite multicavity FPIs are formed, including an air-cavity FPI, a PDMS-cavity FPI and an air-PDMS cavity FPI. The contribution of the different FPIs to the superimposed spectrum is analyzed from the simulated and experimental perspectives. The results demonstrate that the superimposed output spectrum is mainly produced by the air-cavity FPI and the air-PDMS cavity FPI. When the temperature increases, the lengths of the PDMS-cavity and the air-PDMS cavity are enhanced due to the volume expansion of PDMS, and the length of the air-cavity decreases because the air-cavity is compressed by the expanded PDMS. The cavity length variation causes the phase variation in the air-cavity FPI to be the opposite to that in the PDMS-cavity FPI or air-PDMS cavity FPI. Therefore, the phase demodulation sensitivity is enhanced by calculating the differential phase between the air-cavity FPI and the air-PDMS cavity FPI. The experimental results show that the sensitivity amplification factor of differential phase to the single phase of the air-cavity FPI or the air-PDMS cavity FPI is from approximately 1.44–3.25. This phase demodulation method is simpler, faster, more direct, and more convenient than wavelength demodulation from the perspective of demodulating composite interferometers. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has posed great challenges to public health services, government agencies, and policymakers, raising huge social conflicts between public health and economic resilience. Policies such as reopening or closure of business activities are formulated based on scientific projections of infection risks obtained from infection dynamics models. Though most parameters in epidemic prediction service models can be set with domain knowledge of COVID-19, a key parameter, namely, human mobility, is often challenging to estimate due to complex spatio-temporal correlations and social contexts under escalating COVID-19 facilities. Moreover, how to integrate the various implicit features to accurately predict infectious cases is still an open issue. To address this challenge, we formulate the problem as a spatio-temporal network representation problem and propose STEP, a Spatio-Temporal Epidemic Prediction framework, to estimate pandemic infection risk of a city by integrating various real-world conditions (e.g., City Risk Index, climate, and medical conditions) into graph-structured data. We also employ a multi-head attention mechanism in representation learning to extract implicit features for a given city. Extensive experiments have been conducted upon the real-world dataset for 51 states (50 states and Washington, D.C.) of the USA. Experimental results show that STEP can yield more accurate pandemic infection risk estimation than baseline methods. Moreover, STEP outperforms other methods in both short-term and long-term prediction. [ABSTRACT FROM AUTHOR]

Anomaly analytics is a popular and vital task in various research contexts that has been studied for several decades. At the same time, deep learning has shown its capacity in solving many graph-based tasks, like node classification, link prediction, and graph classification. Recently, many studies are extending graph learning models for solving anomaly analytics problems, resulting in beneficial advances in graph-based anomaly analytics techniques. In this survey, we provide a comprehensive overview of graph learning methods for anomaly analytics tasks. We classify them into four categories based on their model architectures, namely graph convolutional network, graph attention network, graph autoencoder, and other graph learning models. The differences between these methods are also compared in a systematic manner. Furthermore, we outline several graph-based anomaly analytics applications across various domains in the real world. Finally, we discuss five potential future research directions in this rapidly growing field. [ABSTRACT FROM AUTHOR]

This study was designed to assess the clinical efficiency and long-term outcomes of hepatic vein (HV) and accessory hepatic vein (AHV) recanalization in patients with HV-type Budd-Chiari syndrome (BCS). A total of 27 patients with HV-type BCS underwent AHV recanalization and 94 patients had HV recanalization at our center from January 2012 to December 2019. The treatment effectiveness and long-term outcomes were compared. Technical success was accomplished in all patients, without any procedure-related complications. The clinical success rates were 96.3% (26/27) and 95.7% (90/94) (p = 1.000). In the AHV and HV groups, re-obstruction was observed in 5 and 36 patients, respectively (p = 0.056). The median primary durations of AHV and HV patency were 64 and 49 months, respectively (p = 0.036), while the median secondary durations of AHV and HV patency were 70 and 64 months, respectively (p = 0.134). The median overall survival after AHV and HV recanalization was 73 and 78 months, respectively (p = 0.263). Our findings suggest that AHV could be employed as a replacement for HV, as a hepatic drainage vein, in HV-type BCS patients. [ABSTRACT FROM AUTHOR]

Background: At present, the choice of treatment modalities for ruptured hepatocellular carcinoma patients in BCLC stage A remains controversial, and this study compared the overall survival of ruptured HCC patients undergoing TACE or hepatectomy. Methods: A total of 283 ruptured HCC patients treated at our liver surgery center were included in our study, of which 175 were treated with hepatectomy and 108 were treated with TACE. To reduce selection bias, we used a propensity score matching (PSM) model, which yielded a total of 88 pairs of patients. We used the Kaplan–Meier method to compare the long-term prognosis, and the Landmark method was used to compare the short-term and long-term prognoses of patients after PSM. Finally, we performed subgroup analysis according to whether it met the Milan criteria. Results: After PSM, in the hepatectomy group, the 1-, 3-, and 5 year OS rates were 73.4%, 45.4%, and 33.9%, respectively. In the TACE group, the 1-, 3-, and 5 year OS rates were 58.5%, 40.6%, and 23.2%, respectively. Within one year, the hepatectomy group had a better prognosis than the TACE group (P = 0.022), but there was no difference in long-term survival(P = 0.936). In the subgroup analysis, in patients who met the Milan criteria, the survival curve indicated that there was no statistically significant difference in the survival prognosis between the two groups (P = 0.294) HR = 1.56(0.68–3.59); in the patients beyond the Milan criteria, the survival time was 28.0 months (20.0–34.0) in patients who underwent hepatectomy and 18 months (9.8–26.2) in patients who underwent TACE, and the survival curve indicated a statistically significant difference (P = 0.043) HR = 1.57(1.01–2.43). Conclusion: Our propensity score-matched study found that ruptured HCC patients treated by hepatectomy had a better short-term prognosis than those treated by TACE, but there was no difference in the long-term prognosis between the two treatment groups. [ABSTRACT FROM AUTHOR]

Background: Medial epicondyle fractures are one of the more common humerus fractures, but humeral medial condyle fracture (HMCF) is rare. Nonunion of medial humeral condyle fractures due to functional exercise is less common.Case Presentation: We report a 5-year-old patient with a nonunion HMCF due to excessive functional exercise, who bruised the elbow 1 year ago and had no positive findings on all imaging studies. On this physical examination, there was a snapping and palpable lump in the elbow joint during movement, but the patient did not feel any discomfort and the range of motion of the joint was normal. X rays and computed tomography (CT) showed that the left HMCF was discontinuous, the broken ends were dislocated, and the joint alignment was poor. Open reduction (OR) and screw fixation was used during the operation, and the patient recovered well at 3-month follow-up.Conclusions: The rarity and low radiographic appearance of displaced HMCF are easily overlooked and can eventually lead to nonunion HMCF, especially when radiographically difficult to visualize before age 5 years. Therefore, regardless of whether there are signs or imaging abnormalities in the growth process of adolescents, they should be vigilant, shorten the time interval for re-examination, and early detection and timely treatment can avoid some complications caused by this. [ABSTRACT FROM AUTHOR]

Federated learning (FL) is designed to protect privacy of participants by not allowing direct access to the participants’ local datasets and training processes. This limitation hinders the server’s ability to verify the authenticity of the model updates sent by participants, making FL vulnerable to poisoning attacks. In addition, gradients in FL process can reveal private information about the local dataset of the participants. However, there is a contradiction between improving robustness against poisoning attacks and preserving privacy of participants. Privacy-preserving techniques aim to make their data indistinguishable from each other, which hinders the detection of abnormal data based on similarity. It is challenging to enhance both aspects simultaneously. The growing concern for data security and privacy protection has inspired us to undertake this research and compile this survey. In this survey, we investigate existing privacy-preserving defense strategies against poisoning attacks in FL. First, we introduce two important classifications of poisoning attacks: data poisoning attack and model poisoning attack. Second, we study plaintext-based defense strategies and classify them into two categories: poisoning tolerance and poisoning detection. Third, we investigate how the combination of privacy techniques and traditional detection strategies can be achieved to defend against poisoning attacks while protecting the privacy of the participants. Finally, we also discuss the challenges faced in the area of security and privacy. [ABSTRACT FROM AUTHOR]

The difference of nutrient composition between organic eggs and conventional eggs has always been a concern of people. In this study, 1H nuclear magnetic resonance (NMR) technique combined with multivariate statistical analyses was conducted to identify the metabolite different in egg yolk and egg white in order to reveal the nutritional components information between organic and conventional eggs. The results showed that the nutrient content and composition characteristics were different between organic and conventional eggs, among which the content of glucose, putrescine, amino acids and their derivatives were found higher in the organic eggs yolk, while phospholipids were demonstrated higher in conventional eggs yolk. Organic acid, alcohol, amine, choline and amino acids were higher in conventional eggs white, but glucose and lactate in organic egg were higher. Our study demonstrated that there are more nutritive components and higher nutritional value in organic eggs than conventional eggs, especially for the growth and development of infants and young children, and conventional eggs have more advantages in promoting lipid metabolism, preventing fatty liver, and reducing serum cholesterol. Eggs have important nutritional value to human body, and these two kinds of eggs can be selected according to the actual nutrient needs. [ABSTRACT FROM AUTHOR]

Background. This research is aimed at establishing a scoring system alpha-fetoprotein+alkaline phosphatase (A-A score) based on preoperative serum alpha-fetoprotein (AFP) and alkaline phosphatase (ALP) levels and to investigate its clinical significance in patients with ruptured hepatocellular carcinoma (rHCC) after hepatectomy. Methods. 175 ruptured hepatocellular carcinoma (HCC) patients treated with hepatectomy were included. Survival analysis was assessed by the Kaplan-Meier method. Prognostic factors were analyzed in a multivariate model. Preoperative serum AFP and ALP values are assigned a score of 1 if they exceed the threshold value and 0 if they are below the threshold value, A-A score is obtained by summing the scores of two variables (AFP, ALP), and the predictive values of AFP, ALP, and A-A score were compared by receiver operating characteristic curve (ROC) analysis, and subgroup analyses were performed to further evaluate the power of A-A scores. Results. Of the 175 patients, 67 (38.3%) had an A-A score of 0, 72 (41.1%) had an A-A score of 1, and 36 (20.6%) had an A-A score of 2. In multivariate analysis, the A-A score, the BCLC stage, and the extent of resection were independent predictors of OS in patients with rHCC. The 1-, 3-, and 5-year OS and RFS in patients with an A-A score of 1 were better than those with an A-A score of 0 and worse than those with an A-A score of 1 (all p < 0.05). Based on the results of ROC analysis, the A-A score is superior to AFP or ALP alone in predicting the prognosis of patients with ruptured HCC. In subgroup analysis, A-A score could accurately predict the prognosis of patients with or without microvascular invasion (MVI) and with different Child-Pugh grades or gender. Conclusions. The A-A score can effectively predict the prognosis of patients after hepatectomy of ruptured hepatocellular carcinoma. At the same time, it also has good evaluation ability in different subgroups. [ABSTRACT FROM AUTHOR]

Background and Aims. Conflicting results are often observed in the prognosis of patients with ruptured hepatocellular carcinoma (rHCC), and there are currently very few studies on the long-term postoperative outcomes of ruptured hepatocellular carcinoma patients. This study aimed to distinguish between the postoperative prognosis of rHCC patients with cirrhosis (rHCC-C) and those without cirrhosis (rHCC-NC) using some serum markers. Methods. We collected the data of 151 rHCC patients treated at our centers from January 2010 to March 2021. 62 had no cirrhosis, and 89 had cirrhosis. The prognosis of rHCC-C and rHCC-NC groups was compared using the Kaplan-Meier method. We used multivariate Cox regression to analyze prognostic factors in rHCC patients, and subgroup analysis was performed on the two groups of patients. Results. The long-term prognosis of rHCC-NC patients was better than that of rHCC-C patients. Tumor diameter, Barcelona clinic liver cancer (BCLC) stage, HBsAg, positive Hepatitis C virus (HCV) antibodies, elevated creatinine, and elevated T-bilirubin were prognostic factors for overall survival (OS) in rHCC-C patients. However, only alpha-fetoprotein (AFP) > 92 ng/mL was a prognostic factor for OS in rHCC-NC patients. In noncirrhotic patients, HBsAg positivity was only associated with OS. Similarly, the presence or absence of microvascular invasion (MVI) also had different results in the two groups. Conclusions. There are differences in serum alpha-fetoprotein (AFP) levels, the presence of microvascular invasion (MVI), and HBsAg positivity between rHCC-C and rHCC-NC patients, indicating that the analysis of these prognostic factors may help improve the management of rHCC patients and provide a direction for future treatment options. [ABSTRACT FROM AUTHOR]

Drug–target interactions (DTIs) prediction research presents important significance for promoting the development of modern medicine and pharmacology. Traditional biochemical experiments for DTIs prediction confront the challenges including long time period, high cost and high failure rate, and finally leading to a low-drug productivity. Chemogenomic-based computational methods can realize high-throughput prediction. In this study, we develop a deep collaborative filtering prediction model with multiembeddings, named DCFME (deep collaborative filtering prediction model with multiembeddings), which can jointly utilize multiple feature information from multiembeddings. Two different representation learning algorithms are first employed to extract heterogeneous network features. DCFME uses the generated low-dimensional dense vectors as input, and then simulates the drug–target relationship from the perspective of both couplings and heterogeneity. In addition, the model employs focal loss that concentrates the loss on sparse and hard samples in the training process. Comparative experiments with five baseline methods show that DCFME achieves more significant performance improvement on sparse datasets. Moreover, the model has better robustness and generalization capacity under several harder prediction scenarios. [ABSTRACT FROM AUTHOR]

Edwardsiella piscicida is an acute marine pathogen that causes severe damage to the aquaculture industry worldwide. The pathogenesis of E. piscicida is dependent mainly on the type III secretion system (T3SS) and type VI secretion system (T6SS), both of which are critically regulated by EsrB and EsrC. In this study, we revealed that fatty acids influence T3SS expression. Unsaturated fatty acids (UFAs), but not saturated fatty acids (SFAs), directly interact with EsrC, which abolishes the function of EsrC and results in the turn-off of T3/T6SS. Moreover, during the in vivo colonization of E. piscicida , host fatty acids were observed to be transported into E. piscicida through FadL and to modulate the expression of T3/T6SS. Furthermore, the esrC R38G mutant blocked the interaction between EsrC and UFAs, leading to dramatic growth defects in DMEM and impaired colonization in HeLa cells and zebrafish. In conclusion, this study revealed that the interaction between UFAs and EsrC to turn off T3/T6SS expression is essential for E. piscicida infection. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer is the most prevalent tumor in Chinese men, and surgery is currently the most important treatment. Billroth II and Roux-en-Y are the anastomosis methods used for reconstruction after gastrectomy. Jejunal intussusception is a rare complication after gastric surgery. Main Body: Intussusception after gastric surgery occurs mostly at the gastrojejunostomy site for Billroth II reconstruction, and the Y-anastomosis site for Roux-en-Y reconstruction. Many studies have reported that postoperative intussusception appears at the anastomosis after bariatric surgery, while a few have reported intussusception at the anastomosis and its distal end after radical gastrectomy. Conclusion: A review was carried out to analyze intussusception after radical gastrectomy with roux-en-y anastomosis during the current situation. And the relevant mechanisms, diagnosis, treatment methods, etc. are described, hoping to provide better guidance for clinicians [ABSTRACT FROM AUTHOR]

Background: Gastric cancer is the most prevalent tumor in Chinese men, and surgery is currently the most important treatment. Billroth II and Roux-en-Y are the anastomosis methods used for reconstruction after gastrectomy. Jejunal intussusception is a rare complication after gastric surgery. Main Body: Intussusception after gastric surgery occurs mostly at the gastrojejunostomy site for Billroth II reconstruction, and the Y-anastomosis site for Roux-en-Y reconstruction. Many studies have reported that postoperative intussusception appears at the anastomosis after bariatric surgery, while a few have reported intussusception at the anastomosis and its distal end after radical gastrectomy. Conclusion: A review was carried out to analyze intussusception after radical gastrectomy with roux-en-y anastomosis during the current situation. And the relevant mechanisms, diagnosis, treatment methods, etc. are described, hoping to provide better guidance for clinicians [ABSTRACT FROM AUTHOR]

Background: A growing body of evidence suggests adverse health outcomes related to intimate partner violence (IPV), including traumatic brain injury (TBI). However, most research in this area has focused on reproductive-aged women. Objective: To examine relationships between IPV (with and without TBI), mental health, and aging-related health outcomes among men and women Veterans across the lifespan. Design: Cross-sectional analysis of Department of Veterans Affairs (VA) administrative data from fiscal years 2000–2019. Descriptive statistics and chi-square analyses were used to compare key comorbidities in matched samples of Veterans with and without IPV (gender-stratified and matched 1:3 based on demographics and index date). Comparisons between those with IPV and TBI relative to IPV alone were also examined. Subjects: Veterans aged 18 + with and without documented IPV in Department of Veterans Affairs (VA) electronic health records (n = 4108 men, 2824 women). Main Measures: ICD codes were used to identify IPV, TBI, and aging-related medical (sleep disorder, hypertension, diabetes, dementia) and common psychiatric (depression, posttraumatic stress disorder, alcohol use disorder, and substance use disorder) diagnoses. Key Results: Demographic characteristics were reflective of VA-enrolled Veterans (men: mean age 66, SD 16; 72% non-Hispanic White; women: mean age 47, SD 13; 64% non-Hispanic White). Relative to Veterans without IPV, both men and women with IPV had higher rates of all examined medical (e.g., sleep disorders, men: 33% vs. 52%; women: 45% vs. 63%) and psychiatric diagnoses (e.g., depression, men 32% vs. 74%; women 59% vs. 91%; all ps <.001), with evidence of an additive effect of TBI on some psychiatric outcomes. Conclusions: IPV is broadly associated with aging-related and mental health, and TBI is a common correlate that may further contribute to psychiatric outcomes. Findings highlight the importance of trauma-informed care and recognizing the potential role of these exposures on men and women Veterans' health across the lifespan. [ABSTRACT FROM AUTHOR]

The advisor-advisee relationship represents direct knowledge heritage, and such relationship may not be readily available from academic libraries and search engines. This work aims to discover advisor-advisee relationships hidden behind scientific collaboration networks. For this purpose, we propose a novel model based on Network Representation Learning (NRL), namely Shifu2, which takes the collaboration network as input and the identified advisor-advisee relationship as output. In contrast to existing NRL models, Shifu2 considers not only the network structure but also the semantic information of nodes and edges. Shifu2 encodes nodes and edges into low-dimensional vectors respectively, both of which are then utilized to identify advisor-advisee relationships. Experimental results illustrate improved stability and effectiveness of the proposed model over state-of-the-art methods. In addition, we generate a large-scale academic genealogy dataset by taking advantage of Shifu2. [ABSTRACT FROM AUTHOR]

• Sintered Ce magnets with various Pr-Nd-Al alloy additions is investigated. • The coercivity of Ce magnet changes from 12.7 to 14.93 kOe. • Sandwich-structure grain boundary phase is helpful to improve the thermal stability of Ce magnet. • Formation mechanism of sandwich-structure grain boundary phase is revealed. In this study, the formation mechanism of sandwich-structure grain boundary phase in sintered Ce magnets with various Pr-Nd-Al alloy additions is investigated in detail. The sandwich-structure grain boundary between the main phases is composed of RE 6 (Fe, TM) 11 Al 3 phase at the center and symmetrical Nd-rich phase at both sides. Based on the analysis of phase diagrams, the formation mechanism is revealed from the following aspects: i) The amorphous formation ability of Nd-rich liquid phase in Ce magnet during sintering can be enhanced by introducing Pr-Nd-Al alloy; ii) The RE 6 (Fe, TM) 11 Al 3 phase preferentially nucleates and grows during the process of cooling; iii) The interfacial tension among Nd-rich liquid phase, main phase and RE 6 (Fe, TM) 11 Al 3 phase contributes to the formation of the sandwich-structure grain boundary. With the addition of Pr-Nd-Al alloy, the activity of Al entering the main phase is inhibited, resulting in almost no reduction of remanence and Curie temperature. The structural stability and decoupling effect of the sandwich-structure grain boundary phase are more conducive to the improvement of the coercivity and thermal stability of the Ce magnets. The coercivity of Ce magnet changes from 12.7 to 14.93 kOe (the increase extent is 17.6%). In the temperature range 20–100 ℃, the coercivity temperature coefficient varies from -0.767 to -0.680 %/℃ and the temperature stability obviously ameliorates about 11.3%. [ABSTRACT FROM AUTHOR]

Background The objective of this study was to evaluate the feasibility, safety, and clinical effectiveness of preoperative computed tomography (CT)-guided transfissural coil localization (TFCL) of subfissural lung nodules. Methods Five patients with lung nodules who underwent CT-guided TFCL before video-assisted thoracoscopic surgery between November 2015 and December 2018 were included. Technical success rates of TFCL and wedge resection were assessed, as well complications and pathological results. Results The technical success rate of TFCL was 100%. Two patients experienced parenchymal hemorrhage around the needle path, and two patients experienced asymptomatic pneumothorax after TFCL. The technical success rate of the wedge resection of lung nodules was also 100%. The pathological diagnoses of the five nodules were minimally invasive adenocarcinoma (n = 3), adenocarcinoma in situ (n = 1), and inflammatory nodule (n = 1). Conclusion CT-guided TFCL is a safe and effective method for the preoperative localization of subfissural lung nodules. [ABSTRACT FROM AUTHOR]

Brassica yellows virus (BrYV) is an economically important virus on cruciferous species. In this study, a one-pot reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay coupled with the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system was developed for the detection of BrYV. The limit of detection of this method reached 32.8 copies of the BrYV ORF5, which is 100-fold more sensitive than the RT-LAMP method. Moreover, there was no cross-reactivity with other rapeseed-infecting RNA viruses or poleroviruses. We dried the CRISPR/Cas12a reagent in a trehalose and pullulan mixture to retain its efficacy at the RT-LAMP temperature of 63°C in order to allow portable BrYV detection in a water bath. The entire process can be performed in about 1 h, and a positive result can be rapidly and conveniently detected using a handheld UV lamp. In the field, the RT-LAMP-CRISPR/Cas12a assay was accurate and had higher sensitivity than RT-LAMP and reverse transcription-polymerase chain reaction assays. The novel RT-LAMP-CRISPR/Cas12a assay allows convenient, portable, rapid, low-cost, highly sensitive, and specific detection of BrYV and has great potential for on-site monitoring of BrYV. [ABSTRACT FROM AUTHOR]

This paper presents a 2-D vector microdisplacement sensor based on mode coupling between single-mode fiber (SMF) and two-mode fiber (TMF). The offset alignment between SMF and TMF along the radial direction of optical fibers can influence the mode coefficients of LP01 mode, LP11o mode, and LP11e mode in TMF, including mode power proportion coefficients and mode relative phase coefficients. Modal decomposition based on digital holography is used for obtaining these mode coefficients. The variations of mode coefficients of all modes in TMF with the change of the offset between SMF and TMF (i.e., microdisplacement) in two vertical directions are simulated. Experimental results are consistent with simulation results, displaying that the microdisplacement in the range from −5 to $5~\mu \text{m}$ along the positive or negative $x$ -axis or $y$ -axis direction can be judged by using the proposed scheme based on mode demodulation technology. [ABSTRACT FROM AUTHOR]

Taxis are one of the representative modes of traffic systems. However, with the emergence of shared cars led by DiDi and Uber in recent years, the traditional taxi companies are facing unprecedented competitions. Without personalized data collected from the mobile devices, passenger flow prediction based on vehicle GPS records presents a unique solution that can improve taxis' operating efficiency while preserving personal privacy. In this paper, we propose the Travel Behavioral Inertia (TBI) from taxi GPS records, which embodies Driver Inertia (DI) and Passenger Inertia (PI). Then we integrate TBI with other features to construct multi-dimensional features and predict taxi passenger flow based on a deep learning algorithm. We call the entire framework TBI2Flow. Extensive experiments demonstrate that TBI features has outstanding contribution to passenger flow prediction and TBI2Flow outperforms state-of-the-art methods including time series-based method and other deep learning-based methods on long-term taxi passenger flow prediction. [ABSTRACT FROM AUTHOR]

• We propose a highly-sensitive phase-interrogated RI sensor based on twin-core fiber with inherent noise suppression. • It is the first time that optical fiber sensing structure is combined with digital holography technology, which works as the phase interrogation method, for measuring environmental parameters. • The background signal is reduced to 1/25 of the original noise level by using phase subtraction method within a single measurement. • Experimental results show that a short response time of about 13 s and a high sensitivity of about 835 rad/refractive index unit (RIU) are obtained. • The achieved high sensitivity is about 47 times higher than the sensitivity of a refractive index plasmonic sensor realized by enabling its quadrupole resonance in phase interrogation (17.46 rad/RIU). In this work, we propose a highly-sensitive phase-interrogated RI sensor based on twin-core fiber with inherent noise suppression. This is the first time that optical fiber sensing structure is combined with digital holography technology, which works as the phase interrogation method, for measuring environmental parameters. The proposed system consists of a Mach–Zehnder interferometer formed by interference between the reference Gauss beam and the sensing dual-beam from the twin-core fiber (TCF). In the sensing optical path, a non-core fiber (NCF) and TCF offset splicing structure works as the differential fluid RI sensing element, which provides the capability of suppressing background signal by calculating the phase difference between the two cores of the TCF. This simple and practical phase subtraction method realizes direct background subtraction within a single measurement and reduces the background signal to 1/25 of the original noise level. The fluid is continuously introduced into a fluid tube in which the sensing fiber is installed to realize in-line measurement of fluid RI. Experimental results show that a short response time of about 13 s and a high sensitivity of about 835 rad/refractive index unit (RIU) are obtained. The high sensitivity benefits from direct interaction between light path and fluid, which is about 47 times higher than the sensitivity of a refractive index plasmonic sensor realized by enabling its quadrupole resonance in phase interrogation (17.46 rad/RIU). This scheme will find many applications in little sample consumption and high sensitivity required analytical measurement owing to its merits of high sensitivity, little sample consumption, fast response, and inherent background noise suppression. [ABSTRACT FROM AUTHOR]

• A self-assembled whispering gallery mode microbottle resonator was fabricated. • The proposed microbottle resonator can be used for acetone gas sensing. • The sensor has merits of small size, low cost, and simple manufacture using non-toxic materials. In this paper, an acetone gas sensor based on a polyvinyl alcohol (PVA) self-assembled whispering gallery mode (WGM) microbottle resonator coated with polydimethylsiloxane (PDMS) is proposed and demonstrated. The preparation of the PVA self-assembled microresonator and the coating of PDMS are all finished by employing a dip coater. Compared with the PVA microresonator and the PDMS microresonator, the PVA microresonator coated with PDMS shows the highest acetone gas sensitivity, which is up to −6.34 pm/ppm. Besides, it can effectively reduce the effects of humidity on the detection of acetone gas compared to the PVA microresonator. Since the concentration of acetone in breathing gas is an indicator of diabetes, the proposed sensor with the benefits of small size, low cost, and simple manufacture using non-toxic materials presents promising applications for painless and non-invasive diagnosis of diabetes. [ABSTRACT FROM AUTHOR]

In spin-cast films of poly(vinylidene fluoride-trifluoroethylene) on metalized silicon substrate, there exists a threshold thickness of crystallization d[sub th], below which the crystallinity drops precipitously. Due to the direct link between the crystallinity and functional properties in the polymer, there is a corresponding large change in the film ferroelectric properties, including the dielectric constant, the polarization level, and polarization switching speed, as the thickness is reduced to below d[sub th]. Detail microstructure studies show that this threshold thickness is controlled by the stable crystal lamellar size along the film thickness direction. By varying the film processing condition to reduce the crystal lamellar size in the thickness direction, d[sub th] can be reduced markedly. As a result, better ferroelectric responses were obtained in ultrathin films. [ABSTRACT FROM AUTHOR]

The effect of postsintering annealing on the dielectric and piezoelectric responses in lead-zincniobate (PZN)-based ferroelectric ceramics was systematically studied in this work. Sintered PZN ceramics with the same composition were annealed at temperatures from 700 to 900 °C from 30 min to 24 h in various atmospheres. As a result, significant improvements in the dielectric and piezoelectric responses were observed in this system. After annealing, there was a huge increase of up to 130% in the dielectric constants, especially near the temperature of maximum dielectric constant. While the dielectric peaks became sharper and less diffuse, there was almost no change in frequency dispersion. Similar large improvements in the piezoelectric properties such as the coupling factor and piezoelectric constant were also observed. Optimized parameters, such as d[sub 33] = 642 pC/N, d[sub 31] = - 256 pC/N, k[sub p] =48% and ∈[sub m] = 28 000, were achieved by annealing at 850 °C in an O[sub 2]-rich atmosphere for 4-8 h. The observed improvement in the electrical properties can be attributed to an extrinsic contribution induced by domain wall motion. After annealing, the pinning effects caused by oxygen vacancies and internal stress on domain wall motion were largely reduced or eliminated, therefore a significantly reduced coercive field, an increased polarization level, and a greatly increased dielectric constant were observed in the PZN-based ferroelectric ceramics. [ABSTRACT FROM AUTHOR]

Highlights • OAM modes are generated by a simple offset splicing and fiber rotating technology. • OAM modes are demonstrated in a broad wavelength range of 1530–1566 nm. • The complexity of the OAM generation system can be reduced by employing PM fibers. • PM fiber can avoid coupling of modes with orthogonal polarizations. Abstract We demonstrate a simple, compact, and cost-effective all-fiber structure to generate the first-order orbital angular momentum (OAM) modes over a broad wavelength range. The offset splicing between a polarization-maintaining single mode fiber (PM-SMF) and a two-mode fiber (TMF) is adopted to excite LP 11 mode in the TMF from LP 01 mode in SMF. Then the OAM ±1,1 modes are generated by rotating a customized fiber rotator, which can modulate the phase difference of the two degenerate LP 11 modes (OAM ±1,1 = LP 11a ± i × LP 11b). The interference phenomenon formed between OAM and Gaussian beams, which displays a fork-shape or spiral interference pattern, is used to confirm the generation of OAM modes. It should be noted that a PM fiber coupler and PM-SMFs are utilized in the experiment, which can avoid coupling of modes with orthogonal polarizations and then improves the OAM mode stability. Besides, the complexity of the OAM generation system is also reduced because the devices like polarization controller and half-wave plate are omitted by employing PM fibers. Based on this simple offset splicing and fiber rotating technology, the broadband generation of OAM ±1,1 modes are experimentally demonstrated in wavelength range of 1530–1566 nm. [ABSTRACT FROM AUTHOR]

A diode-pumped continuous-wave (CW) and passively Q-switched Nd:LuLiF 4 laser was investigated. Under an incident pump power of 11.2 W, an output power of up to 1.92 W was generated, corresponding to a slope efficiency of 17.4%. By using a Cr4+:YAG wafer as saturable absorber, stable Q-switched pulse trains with an average output power of 1.13 W and a pulse duration of 13.8 ns were captured at a repetition rate of 32.5 kHz, delivering a pulse energy of 36.4 μJ. A rate equation model was further introduced to theoretically analyze the dynamical mechanism, in which the Gaussian spatial distribution theory was taken into account. [ABSTRACT FROM AUTHOR]

In recent years, compact micro‐/nanofiber sensors with fast response and high resolution have become a hot field in sensing and nanotechnology. In addition to the unique properties of microfibers such as strong evanescent field, low optical loss, and easy integration, microfiber knot resonators further improve the sensing capability due to their resonance properties. The potential high‐quality factor allows higher sensing sensitivity and resolution, which is very attractive for optical sensing at the micro‐/nano scale. More application potential can be effectively stimulated by improving the structure shape or principle or combining with functional sensitive materials. This paper first introduces the preparation process and spectral characteristics of conventional microfiber knots and then focuses on three new types of devices for enhancing the sensing performance, namely material‐coated, shape‐improved, and principle‐extended, and briefly analyzes their spectral properties. In addition, the research progress and applications of these sensors are summarized. Finally, the existing problems in this field are analyzed, and the directions for further development are discussed and prospected. [ABSTRACT FROM AUTHOR]

Abstract Focusing by the designed negative Luneburg lens which is based on graded annular photonic crystals (GAPCs) are studied in this paper. The GAPCs are composed of ring-shaped silicon pillars in a hexagonal lattice. The gradient of refractive index is achieved by modifying the radii of inner holes. The effective negative refractive index is analyzed based on the photonic band structures and verified by the simulation of negative refraction in APCs flat lens. Numerical simulation results show that a 0.6λ focusing spot can be realized by our designed Luneburg lens and it has the potential to be utilized in photonic integrated circuits. Highlights • We designed a negative Luneburg lens based on the graded annular photonic crystals (GAPCs) by ring-shaped silicon pillars. • The gradient of refractive index is achieved by modifying radii of the inner hole that has been analyzed and verified. • A 0.6λ focusing and coupling by GAPCs Luneburg lens show the potential to be utilized in photonic integrated circuits. [ABSTRACT FROM AUTHOR]

The influence of TiB2 on the fatigue properties of Al-Si-Cu series alloys was discussed with the help of finite element simulation, and the feasibility of the spatial configuration distribution of the reinforcement to solve the problem of inversion of the strength and toughness of the particle reinforced metal matrix composites was verified, and the test efficiency was effectively improved. In this paper, the different content and distribution characteristics of TiB2 particles are introduced into the two-dimensional geometric model of Al-Si-Cu alloy materials through configuration design methods, and the influence of TiB2 particles on the stress amplitude and fatigue limit distribution of aluminum matrix composites under fatigue conditions is discussed with the help of computer finite element simulation technology. The results show that with the increase of TiB2 particle content, the stress amplitude first decreases and then increases. The minimum value at a particle content of 3% is reduced by 12% compared to no addition. The fatigue limit showed a trend of gradual increase, reaching a maximum at 5% TiB2 content, an increase of 55.9% year-on-year. With the increase of TiB2 agglomeration, the stress amplitude showed an overall trend of increase. The fatigue limit shows a trend of gradual reduction. Combined with the simulation results of fatigue stress amplitude and fatigue limit simulation, it is estimated that when the TiB2 particle content is 3%, the strength, toughness, fatigue strength, tensile strength and yield strength of the material reach the optimal state. This result provides some technical support for the design of TiB2 particle-reinforced aluminum matrix composites. [ABSTRACT FROM AUTHOR]

An optical fiber sensing and signal demodulation technology based on Mach-Zehnder interferometer (MZI) and orbital angular momentum (OAM) beam was proposed in this work. One path of the MZI containing only single mode fiber (SMF) emits Gaussian beam, and the other path which contains a segment of two-mode fiber (TMF) generates OAM beam. The OAM beam was generated by offset splicing a segment of TMF with SMF, and then rotating the TMF by using a customized fiber rotator. The interference between the Gaussian beam and the OAM beam generates spiral interference pattern, which can rotate with the change of phase difference between these two beams. A segment of SMF in the Gaussian beam path was used as a sensing fiber, which was placed on a thermostat. When the temperature changes, the phase difference between the Gaussian beam and the OAM beam was changed owing to the thermo-optic effect and thermal expansion effect of the sensing fiber, resulting in the rotation of spiral interference pattern. An optical phase difference demodulation method based on spiral interference pattern feature extraction technology was proposed to demodulate optical phase difference between these two beams. Experimental result shows that the sensing system has a linear temperature measurement sensitivity of 12.67 rad/°C. The temperature measurement resolution is 0.0000122 °C in theory and about 0.005 °C achieved in experiment. [ABSTRACT FROM AUTHOR]

Vehicular social networks (VSNs) have attracted the research community due to its diverse applications ranging from safety to entertainment. Social vehicles standing for private cars and floating cars standing for taxis are two important components of VSN. However, the lack of social vehicles data causes some factors are neglected including social aspects and macroscopic features, which blocks researching social attributes of vehicles in VSN. Generating a realistic mobility dataset for VSN validation has been a great challenge. In this paper, we present the detailed procedure to generate social vehicular mobility dataset from the view of floating car data, which has the advantage of wide universality. First, through the deep analysis and modeling of the dataset of floating cars and combining with the official data, we predict the origin–destination (OD) matrix of social vehicles with the gravity model, and then calibrate the OD matrix with the average growth factor method. Second, we construct network description after editing the road network. Third, we use simulation of urban mobility to reproduce the scenario in view of microsimulation by generating the mobility dataset of social vehicles based on floating car data and urban functional areas. At last, we prove the effectiveness of our method by comparing with real traffic situation in Beijing. The generated mobility model may not accurately represent the mobility of social vehicles in few spots, such as train station or airport, however, exploiting figures and facts of transportation in the city have been considered in the study to calibrate the model up to maximum possible realization. [ABSTRACT FROM PUBLISHER]

A novel and in-line fiber low-frequency vibration sensor based on Butterfly-Shape Mach-Zehnder Interferometer (BSMZI) is proposed and demonstrated experimentally. The sensing element is a tapered hollow-core fiber (HCF) sandwiched between two single-mode fibers (SMFs). The frequency measured by the Butterfly-Shape vibration sensor can well match with the applied frequency, and the presence of the higher harmonics can verify that the sensor does not distort the measured vibration signal. The maximum relative error of vibration frequency is 0.27%. The intensity of vibration signal (of the fiber sensor) is linearly proportional to the driving power of vibration platform. The vibration measurement sensitivity is 13.575 dB/w in the range of 0.1 w to 0.5 w under a constant vibration frequency of 50 Hz, and the linear fitting coefficient is 0.9556. The proposed sensor has a negligible temperature sensitivity in the range of 30.3 °C–69.5 °C. Because of its compact structure, easy preparation, low production cost, high frequency measurement accuracy of low-frequency vibration, and good linearity of vibration sensing, the proposed BSMZI sensor has potential application prospect in low-frequency vibration sensing field. [ABSTRACT FROM AUTHOR]

An optical fiber axial contact force sensor based on bubble-expanded Fabry–Pérot interferometer (FPI) is investigated in this paper. The FPI is packaged as a reflective sensing probe to measure the axial contact force which is applied on the end of sensing probe. To the best of the authors’ knowledge, this is the first time that intrinsic optical fiber FPI is used for axial contact force measurement, which has potential in application fields such as robotics. The sensing probe based on bubble-expanded FPI exhibits a high axial contact force measurement sensitivity of −750.17 pm/N, which is 3 times higher than that of the sensing probe based on traditional rectangular FPI fabricated in this work. This experimental results are well explained by the simulation analysis using Comsol software. The proposed optical fiber axial contact force sensor has advantages of compact size, simple structure and high sensitivity. [ABSTRACT FROM AUTHOR]

Fano resonances have been studied intensely in the last decade, since it is an important way to decrease the resonance line width and enhance local electric field. However, achieving a Fano line-shape with both narrow line width and high spectral contrast ratio is still a challenge. In this paper, we theoretically predict the Fano resonance induced by the extinction of normal plane wave in a ring-shaped hexamer cluster at near-infrared wavelength. In order to obtain the narrow Fano line width and high spectral contrast ratio, the relationships between the Fano line-shape and the parameters of the nanostructure are analyzed in detail. The nanostructure is simulated by using commercial software based on finite element method. The simulation results show that when the structural parameters are optimized, the Fano line width can be narrowed down 0.028 eV with a contrast ratio of 86%, and the local electric field enhancement factor at the Fano resonance wavelength can reach to 36. Furthermore, the effective mode volume of the structure is 3.9 × 10 − 23 m 3 which is lower than the available literature. These results indicate many potential applications of the Fano resonance in multiwavelength surface-enhanced Raman scattering and biosensing. [ABSTRACT FROM AUTHOR]

Smart cities have been recognized as a promising research focus around the world. To realize smart cities, computation and utilization of big data are key factors. More specifically, exploring the patterns of human mobility based on large amounts of multi-source data plays an important role in analyzing the formation of social-economic phenomena in smart cities. However, our acquired knowledge is still very limited for smart cities. In this article, we propose an integrated computing method to rescale heterogeneous traffic trajectory data, which leverages MLE and BIC. Our analysis is based on two real datasets generated by subway smart card transactions and taxi GPS trajectories from Shanghai, China, which contain more than 451 million trading records by 14 subway lines and 34 billion GPS records by 13,695 taxis. Specifically, we quantitatively explore the patterns of human mobility on weekends and weekdays. Through logarithmic binning and data fitness, we calculate the Bayesian weights to select the best fitting distributions. In addition, we leverage three metrics to analyze the patterns of human mobility in two datasets: trip displacement, trip duration, and trip interval. We obtain several important human mobility patterns and discover quite a few interesting phenomena, which lay a solid foundation for future research. [ABSTRACT FROM AUTHOR]

As the important chiral building block of levetiracetam, the synthesis of ( S )-2-aminobutanamide has attracted a great deal of attention. The d -aminopeptidase catalyzed kinetic resolution of 2-aminobutanamide was demonstrated as an effective strategy for ( S )-2-aminobutanamide production. In this study, a novel d -aminopeptidase from Brucella sp. ( Bs -Dap) was screened and systematically characterized. The enzyme exhibited maximum activity at 45 °C, pH 8.0 and it showed relatively low K m value toward 2-aminobutanamide, indicating its high affinity to the substrate. Kinetic resolution of 300 g/L 2-aminobutanamide by recombinant Escherichia coli whole cells (4 g/L wet cell weight) resulted in 50% conversion and >99% e.e. within 80 min. The catalytic properties of Bs -Dap demonstrated its great potential for industrial production of ( S )-2-aminobutanamide. [ABSTRACT FROM AUTHOR]

A compact and highly sensitive temperature sensor based on mode conversion in the ring-core fiber (RCF) incorporating an asymmetric long-period grating (aLPG) is proposed and theoretically simulated. The RCF is composed of a hollow core and a high refractive index ring. The aLPG inscribed in the upper half ring generates mode conversion between modes with different azimuthal orders within the ring. A composite resonant dip containing dual-resonant dips which are generated by mode conversion from HE 11x to \mathrmTE01 and HE 21x can be observed in the transmission spectrum. The hollow core is infiltrated with a refractive index liquid whose material refractive index can be modulated via temperature, so the wavelength of the resonant dip can be modulated by temperature, which displays a high sensitivity of 12.92 nm/°C ( 32.3~\mu \textm /RIU). Furthermore, the relationship between 3-dB bandwidth of the resonant dip and temperature is also obtained by polynomial fitting with a high fitting degree of 99.99%. [ABSTRACT FROM PUBLISHER]

A novel refractive index (RI) sensor based on photonic crystal fiber Mach–Zehnder interferometer (PCF-MZI) was proposed. It was realized by cascading a section of PCF with half-taper collapse regions (HTCRs) between two single mode fibers (SMFs). The relationship between RI sensitivity and interference length of the PCF-MZI was firstly investigated. Both simulation and experimental results showed that RI sensitivity increased with the increase of interference length. Afterwards, influence of HTCR parameters on RI sensitivity was experimentally investigated to further improve the sensitivity. With intensification of arc discharge intensity in HTCR fabrication process, HTCR with larger maximum taper diameter and longer collapsed region length was obtained, which enhanced evanescent field of the PCF-MZI and then generated higher RI sensitivity. Consequently, a high RI sensitivity of 181.96 nm/refractive index unit (RIU) was achieved in the RI range of 1.3333–1.3574. Increasing arc discharge intensity in HTCR fabrication process has the capacity to improve RI sensitivity of PCF-MZI and meanwhile provides higher mechanical strength and longer sensor life compared to the traditional method of tapering the fiber, which improves the RI sensitivity at the cost of reducing mechanical strength of the sensor. This PCF-MZI was characterized by high RI sensitivity, ease of fabrication, high mechanical strength, and robustness. [ABSTRACT FROM AUTHOR]

Mach–Zehnder interferometers have attracted attention due to their flexible structures and extensive applications. In this study, a simple and highly sensitive curvature sensor based on an asymmetrical Mach–Zehnder interferometer comprising an up-taper and a peanut-like section was theoretically and experimentally characterized. A simulation was conducted to investigate the influence of structural parameters on the interference spectrum. Experimental measurements show that a high curvature sensitivity of −35.3 nm/m−1from 1.35 to 2.20 m−1was obtained and high mechanical strength was demonstrated. The temperature–curvature cross-sensitivity of 4.44 × 10−4 m−1/°C was lower than the curvature resolution. The high curvature sensitivity and low temperature cross-sensitivity make this sensor a candidate for practical applications. [ABSTRACT FROM PUBLISHER]

Purpose: To determine the clinical efficiency and long-term outcomes between unilateral and bilateral stent insertion in patients with malignant hilar biliary obstruction. Methods: From August 2012 to February 2016, 63 consecutive patients with malignant hilar biliary obstruction were treated with unilateral or bilateral stent insertion at our center. The bilateral stents were inserted using the side-by-side technique. The clinical efficiency and long-term outcomes were compared between the two groups. Results: Unilateral and bilateral stent insertions were successfully performed in 31 of 33 and 27 of 30 patients, respectively ( P = 0.912). No procedure-related complication occurred. Clinical success was achieved in 29 of 31 patients in the unilateral stent group and in 26 of 27 patients in the bilateral stent group ( P = 0.637). During the follow-up, re-obstruction of stent occurred in five patients in the unilateral stent group and in three patients in the bilateral stent group ( P = 0.58). The significant differences were not observed in the stent patency time (368 vs. 387 days, P = 0.685) and survival (200 vs. 198 days, P = 0.751) between two groups. Based on the univariate and multivariate analyses, the independent risk factors for decreasing the survival time included higher Eastern Cooperative Oncology Group performance status ( P = 0.018), higher alanine aminotransferase level ( P = 0.009), and absence of anticancer treatment after stent insertion ( P = 0.002). Conclusion: Compared to bilateral stent insertion for malignant hilar biliary obstruction, unilateral stent insertion can provide comparable clinical efficiency and long-term outcomes. [ABSTRACT FROM AUTHOR]

A novel Mach–Zehnder Interferometer (MZI) formed by cascading two vase-shaped tapers in a single mode fiber (SMF) is proposed in this work. The vase-shaped taper is fabricated by fusion splicing a fiber sphere with a fiber tip by applying strong arc discharge. The curvature sensing characteristic of the proposed vase-shaped taper-based MZI is experimentally investigated, displaying that the interference spectrum has a blue shift with the increase of applied curvature. The sensor realizes a large range measurement of curvature from 0.9284 m −1 to 4.0470 m −1 with sensitivities of −8.41 nm/m −1 and −16.72 nm/ m −1 in the curvature range of 0.9284 m −1 to 2.4564 m −1 and 2.6025 m −1 to 4.0470 m −1 , respectively. Its temperature-curvature cross-sensitivities are −0.0021 m −1 / °C and −0.0011 m −1 / °C in the two measurement ranges, which are lower than the corresponding curvature resolutions which are 0.0024 m −1 and 0.0012 m −1 . The proposed sensor exhibits the advantages of low cost, negligible temperature cross-sensitivity, fine curvature sensitivity and large measurement scale. [ABSTRACT FROM AUTHOR]

All-fiber Mach-Zehnder interferometers (MZIs) working as curvature sensors have been attracting increasing attention. However, previously reported MZI-based curvature sensors with offset or abrupt-taper structures suffer from weak mechanical strength and low curvature sensitivity. In this letter, a robust and highly-sensitive MZI-based curvature sensor formed by cascading two up-tapers in a single mode fiber (SMF) is proposed and experimentally demonstrated. By optimizing structural parameters of the MZI both in simulation and in experiment, a high quality interference spectrum with a maximum extinction ratio (ER) of around 20 dB is obtained, which is crucial in curvature sensing with spectrum intensity variation and interference dip identifiability being considered. Experimental results show that a high curvature sensitivity of −35.41 nm/m −1 is obtained in the range of 0.6846 m −1 – 1.0606 m −1 , which is 2.4 times higher than that of the interferometer with single-mode-multimode-single-mode (SMS) structure. The two up-tapers, featured by great mechanical strength, are fabricated by only fusion pushing together a whole SMF without cleaving procedure, contributing to excellent repeatability and consistency in the sensor fabrication process. Such an all-fiber sensor exhibits advantages of simple configuration, ease of fabrication, excellent mechanical strength, low cost, and high curvature sensitivity. [ABSTRACT FROM AUTHOR]