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We present a discrete event simulator, TSJSim (Truck-Shovel JaamSim Simulator), for evaluating the stochastic and dynamic operational variables in a truck-shovel system. TSJSim offers four truck allocation strategies: Fixed truck assignment (FTA), Minimizing shovel production requirement (MSPR), Minimizing truck waiting time (MTWT), and Minimizing truck semi-cycle time (MTSCT) including the genetic algorithm (GA) optimization and the frozen dispatching algorithm (FDA) optimization rules. Multiple decision points along the haul routes for all the trucks close to the decision points were included in the model. The simulation results indicate that the trends associated with production tons and queuing time utilizing the four truck allocation strategies (MSPR, MTWT, FDA, and GA) all demonstrated similar patterns as the fleet size varied. As the system fleet size increased, the system production tons under these strategies at first increased significantly and then remained relatively constant; the queuing time relating to these strategies showed a positive relationship with the system fleet size. The bunching time decreased when the truck allocation strategies were applied in the model. In the simulated truck-shovel network system with multiple traffic intersections, by assigning the trucks at the intersections, both productivity and fleet utilization increased.

Nickel-based complex oxides have served as a playground for decades in the quest for a copper-oxide analog of the high-temperature superconductivity. They may provide clues towards understanding the mechanism and an alternative route for high-temperature superconductors. The recent discovery of superconductivity in the infinite-layer nickelate thin films has fulfilled this pursuit. However, material synthesis remains challenging, direct demonstration of perfect diamagnetism is still missing, and understanding of the role of the interface and bulk to the superconducting properties is still lacking. Here, we show high-quality Nd0.8Sr0.2NiO2 thin films with different thicknesses and demonstrate the interface and strain effects on the electrical, magnetic and optical properties. Perfect diamagnetism is achieved, confirming the occurrence of superconductivity in the films. Unlike the thick films in which the normal-state Hall-coefficient changes signs as the temperature decreases, the Hall-coefficient of films thinner than 5.5 nm remains negative, suggesting a thickness-driven band structure modification. Moreover, X-ray absorption spectroscopy reveals the Ni-O hybridization nature in doped infinite-layer nickelates, and the hybridization is enhanced as the thickness decreases. Consistent with band structure calculations on the nickelate/SrTiO3 heterostructure, the interface and strain effect induce a dominating electron-like band in the ultrathin film, thus causing the sign-change of the Hall-coefficient.

Observation of high energy and very high emission from Gamma Ray Bursts (GRBs) is crucial to study the gigantic explosion and the underline processes. With a large field-of-view and almost full duty cycle, the Water Cherenkov Detector Array (WCDA), a sub-array of the Large High Altitude Air Shower Observatory (LHAASO), is appropriate to monitor the very high energy emission from unpredictable transients such as GRBs. Nevertheless, the main issue for an extensive air shower array is the high energy threshold which limits the horizon of the detector. To address this issue a new trigger method is developed in this article to lower the energy threshold of WCDA for GRB observation. The proposed method significantly improves the detection efficiency of WCDA for gamma-rays around the GRB direction at 10-300 GeV. The sensitivity of the WCDA for GRB detection with the new trigger method is estimated. The achieved sensitivity of the quarter WCDA array above 10 GeV is comparable with that of Fermi-LAT. The data analysis process and corresponding fluence upper limit for GRB 190719C is presented as an example.

The main scientific goal of LHAASO-WCDA is to survey gamma-ray sources with energy from 100 GeV to 30 TeV. To observe high-energy shower events, especially to measure the energy spectrum of cosmic rays from 100 TeV to 10 PeV, a dynamic range extension system (WCDA++) is designed to use a 1.5-inch PMT with a dynamic range of four orders of magnitude for each cell in WCDA-1. The dynamic range is extended by using these PMTs to measure the effective charge density in the core region of air shower events, which is an important parameter for identifying the composition of primary particles. The system has been running for more than one year. In this paper, the details of the design and performance of WCDA++ are presented.

OBJECTIVE: To explore the effect of thoracic paravertebral anesthesia (TPVB) on prognosis of patients undergoing resection of lung cancer. METHODS: This study was conducted among the patients undergoing surgical resection of primary lung cancer under general anesthesia or TPVB combined with general anesthesia (TPVB+GA) between January, 2017 and May, 2018.The patients were enrolled in TPVB+GA group and GA group (control group) using a propensity score matching (PSM) method at the ratio of 1:2 based on their baseline characteristics.The clinical parameters, 5-year overall survival (OS), progression-free survival (PFS) and intraoperative dosage of opioids were compared between the two groups to assess the impact of TPVB on prognosis of the patients. RESULTS: Forty-seven patients were enrolled in TPVB+GA group and 94 in the control group.Kaplan-Meier survival analysis showed a significantly prolonged PFS in the patients with TPVB+GA (log-rank P=0.034), with an odds ratio (OR) of 0.45(95%CI: 0.33-0.89).Consistently, univariate and multivariate Cox regression analyses identified TPVB as an independent protective prognostic factor for patients with lung cancer resection (P=0.002, OR=0.33, 95%CI: 0.16-0.66).Cox regression analyses indicated that a lower intraoperative dose of remifentanil was significantly correlated with a longer PFS of the patients following lung cancer resection (P=0.017, OR=0.47, 95%CI: 0.25-0.87).Chi-square test confirmed that TPVB, but not general anesthesia, significantly reduced intraoperative dose of remifentanil, indicating a possible synergistic effect of TPVB with opioids to affect the survival of the patients. CONCLUSION: TPVB can prolong the survival time and improve the prognosis of the patients undergoing surgical resection of lung cancer.

Leveraging on the provisions of the internet enhances the productivity of Micro and Small Enterprises (MSEs), increases industrial growth and their contributions to national prosperity. Every cyber-attack against their businesses should be reported to the requisite incident response body through the appropriate channels for quick recovery from attack. This research examines how the MSEs in Nigeria report cybersecurity incidents. This study surveyed 100 MSEs. The outcome of the research shows that 72% of the MSEs is unaware of the channel of reporting cyber incidents and does not report cyber incidents. Participants totaling 90% believe that the Sectoral Computer Security Incident Response Team (CSIRT) could improve on reporting of cybersecurity incidents through sensitisation. Amongst others, we recommended the Sectoral CSIRTs were to develop an Incident Report and Response Plan (IRRP) for managing cybersecurity incidents in MSEs.

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 105 and 109 GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

OBJECTIVE: To explore the changes in Yes-associated protein (YAP) activity at the early stage of nonalcoholic steatohepatitis (NASH) and the spatiotemporal relationship between YAP and ductular reaction (DR). METHODS: Male C57BL/6J mouse models of NASH were established by feeding with a methionine- and choline-deficient (MCD) diet or a thioacetamide (TAA) diet for 12 weeks. At different time points during the feeding, liver histology of the mice was observed with HE and Masson trichrome staining. The mRNA expressions of YAP and its target genes (Ctgf, Cyr61, Acta2) were determined by qPCR, and the total protein expression level of YAP was measured with immunoblotting. The expression and distribution of YAP and the markers of DR (K19 and Sox9) were observed with immunohistochemical staining. RESULTS: At the early stage of NASH induced by MCD diet (1 to 4 weeks), the mRNA expression of YAP and its target genes and the total protein expression of YAP increased significantly (P < 0.01). The number of YAP-positive hepatocytes reached the peak level of 90.8 (cells per ×400 field of view) at week 2 and then decreased to 30.8 at week 4 (P < 0.001); YAP-positive ductular cells appeared near the portal area, where DR began to occur. From 8 to 12 weeks, numerous K19/Sox9-positive DR cells were observed in the hepatic lobules around the central vein (P < 0.01), while only a few YAP-positive hepatocytes were present in the liver tissue (P > 0.05), and the number of YAP-positive ductular cells gradually increased with time (P < 0.001). At the early stage of NASH induced by TAA diet (3 days to 2 weeks), the mRNA expression of YAP and its target genes and the total protein expression of YAP increased significantly (P < 0.05), and the number of YAP-positive hepatocytes reached the peak of 69.2 at week 2 and then decreased to 55.2 at week 4 (P < 0.001); YAP-positive ductular cells first appeared at the initial location of DR near the central vein. From 6 to 12 weeks, numerous K19/Sox9-positive DR cells occurred in the hepatic lobules around the central vein (P < 0.01). While the number of YAP-positive hepatocytes decreased (P < 0.001), the number of YAP-positive ductular cells continued to increase (P < 0.001). CONCLUSION: During the development of NASH, YAP activation occurs earlier than DR but they are spatiotemporally correlated. YAP activation in hepatocytes may participate in DR by promoting hepatocyte dedifferentiation.

This article serves to highlight both the common nature and severity of postpartum hemorrhage (PPH). Identification of etiologies and management of each is reviewed. In addition, the evaluation and administration of proper blood component therapies and massive transfusion are also explained to help providers become comfortable with early administration and delivery of blood component therapies.

Water Cherenkov detector array (WCDA) is one of the key parts of the Large High Altitude Air Shower Observatory (LHAASO), the construction of which was completed by the end of 2020. The WCDA covers a 78 000-m2 area and there exist 3120 large size photomultiplier tubes (PMTs) in three ponds: 8-in PMTs are used in WCDA pond No. 1 and 20-in PMTs are used in ponds No. 2 and No. 3. The front-end electronics (FEE) system based on multigain measurement technique is designed to achieve both high-precision time and charge measurements over a large dynamic range from single photon electron (S.P.E.) to 4000 P.E. (for water pond No. 1)/1800 P.E. (for water ponds No. 2 and No. 3). To achieve a high-quality clock distribution and phase alignment as well as mixed transmission of data, clock, and commands in one fiber over a long distance, an enhanced white rabbit (WR) technique is used. Testing of all the 350 FEE modules for the WCDA is presented in this article. Test results indicate that the charge resolution is better than 20% at S.P.E. and 1% at 1800/4000 P.E. and the time resolution is better than 300 ps root mean square (rms), which successfully meets the application requirement. All the FEE modules have been fabricated and installed for the LHAASO WCDA from 2018 to 2020, and the initial commissioning operation indicates that the FEEs function well.

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons—cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3–6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators. Observations of γ-rays with energies up to 1.4 PeV find that 12 sources in the Galaxy are PeVatrons, one of which is the Crab Nebula.

Background Human skin, which is constantly exposed to solar ultraviolet radiation (UVR), has a unique ability to respond by increasing its pigmentation in a protective process driven by melanogenesis in human epidermal melanocytes (HEMs). However, the molecular mechanisms used by HEMs to detect and respond to UVR remain unclear. Objectives To investigate the function and potential mechanism of opsin 5 (OPN5), a photoreceptor responsive to UVR wavelengths, in melanogenesis in HEMs. Methods Melanin content in HEMs was determined using the NaOH method, and activity of tyrosinase (TYR) (a key enzyme in melanin synthesis) was determined by the l-DOPA method. OPN5 expression in UVR-treated vs. untreated HEMs and explant tissues was detected by reverse-transcription quantitative polymerase chain reaction (RT-qPCR), Western blotting and immunofluorescence. Short interfering RNA-mediated OPN5 knockdown and a lentivirus OPN5 overexpression model were used to examine their respective effects on TYR, tyrosinase-related protein 1 (TRP1), TRP2 and microphthalmia-associated transcription factor (MITF) expression, under UVR. Changes in expression of TYR, TRP1 and TRP2 caused by changes in OPN5 expression level were detected by RT-qPCR and Western blot. Furthermore, changes in signalling pathway proteins were assayed. Results We found that OPN5 is the key sensor in HEMs responsible for UVR-induced melanogenesis. OPN5-induced melanogenesis required Ca2+ -dependent G protein-coupled receptor- and protein kinase C signal transduction, thus contributing to the UVR-induced MITF response to mediate downstream cellular effects, and providing evidence of OPN5 function in mammalian phototransduction. Remarkably, OPN5 activation was necessary for UVR-induced increase in cellular melanin and has an inherent function in melanocyte melanogenesis. Conclusions Our results provide insight into the molecular mechanisms of UVR sensing and phototransduction in melanocytes, and may reveal molecular targets for preventing pigmentation or pigment diseases.

We theoretically study the Josephson effect in a superconductor/normal metal/superconductor junction based on Kekul\'e patterned graphene. For the Kekul\'e-O patterned junctions, a Fermi momentum-splitting Andreev reflection at the interface can be induced by the off-resonant circularly polarized light applied in the normal region, which results in the possible $\pi$-state. In contrast, for the Kekul\'e-Y patterned junctions, the Fermi momentum-splitting Andreev reflection is strongly suppressed due to the valley-momentum locking and the junction always exhibits the 0-state. The dependence of the critical current on the junction length and the illumination parameter of the light field is also presented in detail., Comment: 7 pages, 7 figures

This paper reported antibiotic resistance and PFGE genetic typing of Streptococcus thermophilus stains isolated from different yogurt brands in Chinese market. In total, 42 strains isolated from 43 yogurt samples were identified as S. thermophilus stains by 16S rDNA sequence analysis. The investigation of antibiotic-resistance profiles revealed that those isolates were resistant to erythromycin (69.05 %), clindamycin (73.81 %), chloramphenicol (61.90 %) and fosfomycin (19.05 %), and were susceptible to other 13 kinds of antibiotics. The genetic typing of S. thermophilus stains was examined by pulsed-field gel electrophoresis (PFGE) of chromosomal DNA digested with SmaI. The enzyme restriction profiles showed the 42 S. thermophilus isolates were divided into 14 PFGE types, and further analysis showed the PFGE profile did not completely match with antibiotic resistance profile. The antibiotic resistance and PFGE pattern database generated in this study suggest that the safety evaluation of S. thermophilus should be paid more attention and will provide basic for information of food safe assessment of yogurt.

The Macao Dementia Policy was recognized by Alzheimer Disease International as the 27th globally and one of the highest stage 5 to develop dementia friendly community and primary health professionals are in a pivotal position to enhance community-based dementia prevention and care quality. This study aimed to investigate the knowledge, attitude and preventive practice on dementia care among primary health professionals in Macao. A specially designed 30-item questionnaire was developed and validated for the study. The Content Validity Index (CVI) and Cronbach’s α of the questionnaire were 0.973 and 0.808. The questionnaires were distributed to all 375 primary health professionals from 8 Health Centers throughout Macao and 234 valid questionnaires (62.4%) were returned. The score for dementia care knowledge was 87.02+14.01; attitude was 69.52+5.83; preventive practice was 77.88+13.18, of which doctors (79.89+13.77) was significantly higher (t=2.29, p=0.023) than nurses (75.91+12.33). There were positive relationships between preventive practice and attitude (r=0.163, p=0.014), and age (r=0.212, p=0.002), and a negative relationship between knowledge and age (r=-0.139, p=0.040). These findings have significant implications that most primary health professionals in Macao had sufficient knowledge, a positive attitude and appropriate preventive practice on dementia care. However, enhanced dementia education to improve knowledge and preventive practice was a strong agenda for the training for senior staff and nurses.

本文报道1例发生于中年女性扁桃体的软斑病。患者女，43岁，因“右侧咽部异物感1个月余”就诊于福建医科大学附属第二医院。查体：右侧扁桃体Ⅱ度肿大，下极见一苍白乳头状肿物，表面凹凸不平，蒂部无法窥及。术前诊断扁桃体肿物，在全身麻醉下行低温等离子辅助下右侧扁桃体肿物切除术。术中见右侧扁桃体乳头状新生物，大小3.5 cm×2.1 cm×0.9 cm，下至扁桃体下极，部分累及舌根。术后病理诊断为软斑病。术后予盐酸莫西沙星片治疗，好转出院。1个月后：患者右侧咽部见一苍白乳头状肿物、颈部levelⅡ区可触及一肿物，大小3.5 cm×3 cm×2 cm。颈部CT平扫+增强：右颈部多发囊实性占位，考虑炎性改变可能。临床诊断：右侧咽部软斑病，右颈部肿物软斑病可能性大。予莫西沙星抗感染治疗后，右颈部肿痛好转，办理出院。出院1个月后随访，患者诉颈部肿痛复发，就诊外院（具体不详），之后患者失访。.

In this article the author name Ana Alastruey-Izquierdo was incorrectly written as Ana Alastruey-Izquerdo. © Mushroom Research Foundation 2022.

Background: It is hypothesised that simulation enhances progression along the initial phase of the surgical learning curve. Objective: To evaluate whether residents undergoing additional simulation, compared to conventional training, are able to achieve proficiency sooner with better patient outcomes. Design, setting, and participants: This international, multicentre, randomised controlled trial recruited 94 urology residents with experience of zero to ten procedures and no prior exposure to simulation in ureterorenoscopy, selected as an index procedure. Intervention: Participants were randomised to simulation or conventional operating room training, as is the current standard globally, and followed for 25 procedures or over 18 mo. Outcome measurements and statistical analysis: The number of procedures required to achieve proficiency, defined as achieving a score of ≥28 on the Objective Structured Assessment of Technical Skill (OSATS) scale over three consecutive operations, was measured. Surgical complications were evaluated as a key secondary outcome. This trial is registered at www.isrctn.com as ISCRTN 12260261. Results and limitations: A total of 1140 cases were performed by 65 participants, with proficiency achieved by 21 simulation and 18 conventional participants over a median of eight and nine procedures, respectively (hazard ratio [HR] 1.41, 95% confidence interval [CI] 0.72–2.75). More participants reached proficiency in the simulation arm in flexible ureterorenoscopy, requiring a lower number of procedures (HR 0.89, 95% CI 0.39–2.02). Significant differences were observed in overall comparison of OSATS scores between the groups (mean difference 1.42, 95% CI 0.91–1.92; p < 0.001), with fewer total complications (15 vs 37; p = 0.003) and ureteric injuries (3 vs 9; p < 0.001) in the simulation group. Conclusions: Although the number of procedures required to reach proficiency was similar, simulation-based training led to higher overall proficiency scores than for conventional training. Fewer procedures were required to achieve proficiency in the complex form of the index procedure, with fewer serious complications overall. Patient summary: This study investigated the effect of simulation training in junior surgeons and found that it may improve performance in real operating settings and reduce surgical complications for complex procedures. © 2021 European Association of Urology