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Understanding the impact forces exerted by debris flows is limited by a lack of direct field measurements and validated numerical models. In this study, we use real-time impact-force measurements and field observations of debris flows recorded by a sensor network in Jiangjia Ravine, China, to quantify the impact-force distribution of natural debris flows. We observed one debris flow event during and after a storm on August 25, 2004, including 42 short-duration surges and seven long-duration surges, and impact-force signals were successfully recorded for 38 surges. Our observed debris flows comprise high-viscosity laminar flows with high sediment concentration and frequent solid-to-solid interactions. We identified a large magnitude (up to 1 kN), high-frequency (greater than 1 Hz) fluctuating component of the impact force that we interpret as solid particle impact on the sensors. The variability of particle impact forces increases with the mean impact force. Our results show that a log-logistic distribution can describe the probability density distribution of impact forces. Solid-dominated surges and fluid-dominated intersurge flows have similar impact-force distributions, but surges usually have heavy tails. We created a dimensionless number to describe the impact force and correlated it against existing dimensionless parameters. Finally, we develop a simple particle impact model to understand the relationship between flow dynamics and the impact force inside debris flows that could be applied to improve debris-flow flume experiments and design debris-flow hazard mitigation measures.

This is a pilot study to assess the utility of applying 5G-assisted remote guidance in laparoscopic simulation training. A single trainee of a junior surgeon was recruited to complete three steps of tasks including basic task 1, basic task 2, and model task, and the performance was recorded and evaluated. The operator completed each task three times. Except for basic task 1, all tasks were remotely guided by a more experienced surgeon using 5G technology. Tasks completion time and a 30-point objective structured assessment of technical skills (OSATS) score were utilized to assess the results of simulation training. All remote guidance processes were successfully completed without significant network latency. Through basic task 1, the operator quickly became familiar with the trained laparoscopic instruments. For basic task 2, OSATS scores increased from 16 to 24 points, and completion time decreased from 1500 to 986 s after training under 5G-assisted remote guidance. For model tasks, OSATS scores increased from 15 to 26 points, and completion time decreased from 1734 to 1142 s. This is a novel mode of laparoscopic simulation training to increase the convenience of training. Perhaps in the near future, surgeons can simulate difficult operations at home or in the office, and accurately grasp the possible situations that may occur in actual operations in advance.The online version contains supplementary material available at 10.1007/s12262-022-03590-2.

Shilin He,1,* Tunan Yu,1,* Parikshit Asutosh Khadaroo,2,3 Liuxin Cai,1 Yeyuan Chu,4 Fangqiang Wei,5 Xiao Liang1 1Department of General Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People’s Republic of China; 2Monash University, School of Medicine, Nursing and Health Sciences, Melbourne, Australia; 3School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, People’s Republic of China; 4School of Nursing, Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, People’s Republic of China; 5Department of Hepatobiliary and Pancreatic Surgery, Zhejiang Provincial People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xiao LiangDepartment of General Surgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, Zhejiang Province, People’s Republic of ChinaTel/Fax +86-571-8600-6605Email srrshlx@zju.edu.cnPurpose: Incidental gallbladder cancer (IGBC) is defined as gallbladder cancer (GBC) that is accidentally discovered during cholecystectomy to treat benign lesions. We aimed to compare the prognosis of IGBC patients who underwent simultaneous radical resection (SIR) vs salvage radical resection (SAR).Patients and Methods: We retrospectively reviewed data for IGBC patients admitted to Sir Run Run Shaw Hospital from January 2000 to May 2016. Survival analysis was performed using Kaplan–Meier (univariate) and COX regression (multivariate) analyses.Results: Eighty-four patients with IGBC underwent radical resection; 43/84 underwent SIR, and 41/84 underwent SAR. Compared with SIR, the SAR group was more likely to receive comprehensive preoperative radiographic evaluation, port-site excision, and have more lymph nodes excised (all P < 0.05). Kaplan–Meier analysis indicated that the prognosis in the SAR group was better than that in SIR (overall survival: P = 0.050, recurrence-free survival: P = 0.028). Regression analysis indicated that the type of radical resection (SIR/SAR) was not an independent prognostic factor (overall survival: P = 0.737, recurrence-free survival: P = 0.957).Conclusion: Patients undergoing SAR had non-inferior survival compared with SIR. It is possible that patients in SAR underwent preoperative radiographical evaluations more comprehensively and the surgical operations were more well performed.Keywords: incidental gallbladder carcinoma, simultaneous surgery, salvage surgery, prognosis

The protein, tripartite motif containing 24 (TRIM24) is a member of the TRIM protein family, and acts as a critical co‐regulator of multiple nuclear receptors. TRIM24 is dysregulated in many cancers, including colorectal carcinoma. However, its biological functions and molecular mechanisms with respect to colorectal carcinoma are still largely unknown. In the current study, we found that TRIM24 promotes YAP signaling for driving cell proliferation in colorectal cancer. TRIM24 was significantly upregulated in colorectal carcinoma, and its expression was negatively correlated with the survival of patients. Depletion of TRIM24 impaired the ability of the cancer cells to proliferate and form colonies. Furthermore, this study also revealed the mechanism underlying the recruitment of TRIM24 by the DANCR/KAT6A complex, which is bound to acetylated lysine 23 of histone H3 (H3K23), resulting in binding to the YAP promoter and activation of YAP transcription that ultimately enhances the proliferation of colorectal cancer cells. Our results revealed a novel mechanism involving TRIM24‐YAP signaling for the regulation of colorectal cancer. We also identified TRIM24 as a potential therapeutic molecule for targeting colorectal cancer., Here, we evaluated TRIM24 expression in colorectal cancer, and revealed a positive correlation between TRIM24 expression level and survival prognosis. TRIM24 promotes cell proliferation via YAP signaling. Finally, potential mechanism of DANCR/KAT6A complex on TRIM24 response was explored.

To help health workers and the public recognize and deal with the 2019 novel coronavirus (2019‐nCoV) quickly, effectively, and calmly with an updated understanding. A comprehensive search from Chinese and worldwide official websites and announcements was performed between 1 December 2019 and 9:30 am 26 January 2020 (Beijing time). A latest summary of 2019‐nCoV and the current outbreak was drawn. Up to 24 pm, 25 January 2020, a total of 1975 cases of 2019‐nCoV infection were confirmed in mainland China with a total of 56 deaths having occurred. The latest mortality was approximately 2.84% with a total of 2684 cases still suspected. The China National Health Commission reported the details of the first 17 deaths up to 24 pm, 22 January 2020. The deaths included 13 males and 4 females. The median age of the people who died was 75 (range 48‐89) years. Fever (64.7%) and cough (52.9%) were the most common first symptoms among those who died. The median number of days from the occurence of the first symptom to death was 14.0 (range 6‐41) days, and it tended to be shorter among people aged 70 years or more (11.5 [range 6‐19] days) than those aged less than 70 years (20 [range 10‐41] days; P = .033). The 2019‐nCoV infection is spreading and its incidence is increasing nationwide. The first deaths occurred mostly in elderly people, among whom the disease might progress faster. The public should still be cautious in dealing with the virus and pay more attention to protecting the elderly people from the virus., Highlights The 2019‐nCoV infection is spreading and its incidence is increasing nationwide.The first occurred deaths were majorly elderly people who might have faster disease progression.Although the current mortality is lower than that of the SARS‐CoV and the MERS‐CoV, it seems that the 2019‐nCoV is very contagious.The public should still be cautious in dealing with the virus and pay more attention to protecting the elderly people from the virus.

A disastrous landslide occurred at the Hong’ao Waste Disposal Site in Shenzhen, China on December 20, 2015, involving a volume of 2.7 × 106 m3 of municipal solid waste (MSW) that travelled a distance of 700 to 800 m, covering an area of 3.8 × 105 m2 and caused 90 casualties. The geomorphological and geological characteristics of the waste disposal site were carefully examined and the landslide was classified as an extremely rapid flowslide. The major feature of the waste site was the basin-like structure with the bottom composed of low-permeable granite bedrock. Therefore, surface runoff could easily accumulate in the MSW due to the lack of drainage system, resulting in an increasing groundwater level. Laboratory tests, including physical characterization, Consolidation Isotropic Undrained (CIU) test and direct shear test were conducted to characterize the material properties of the MSW. Physical characterization indicated the MSW belongs to sandy silt, CIU tests indicated that static liquefaction was conducive to high-speed sliding. The direct shear test data were used to carry out numerical analysis of slope stability, in which the continuous rise in the groundwater level was taken into account. Numerical simulation showed that the pore water pressure induced by underground water seepage and gradual loading from the upper MSW placement aggravate the failure. Consequently, the main reason of the landslide could be concluded as follows: 1) the perched groundwater level due to a large upstream catchment area and the lack of drainage system; 2) the excess pore water pressure induced by static liquefaction played a significant role in its mobility.

Studies have shown that the antecedent effect precipitation (AEP) is closely related to rainfall intensity-duration (ID) threshold of debris flow. However, the quantitative relationship between the AEP and ID threshold is still undetermined. In this study, a hydrological process based numerical model (Dens-ID) that can derive the ID threshold curve is adopted to address this issue. Jiangjia Gully (JJG) in Dongchuan District of Yunnan Province was chosen as the study area, Dens-ID was used to derive a series of ID threshold curves corresponding to different AEP. Based on calculated data sets including AEP, ID curves, parameters of ID curve equation (α and β), and debris flow density, the influence of AEP on the ID threshold curve is deeply explored. We found that although solid materials and runoff are the two necessary conditions for the formation of debris flow, the specific roles played in which are different: the volume of loose solid sources provides a basal condition for debris flow and determines the scale of debris flow, while the runoff volume will have a sudden change during the rainfall process, which is a key factor promoting the formation of debris flow. In the condition of AEP ranging from 20 mm to 90 mm, AEP and α can be described by the equation α = −0.0078AEP2 + 0.68AEP + 6.43, and β shows a linear change law with AEP. The error of the two equations were evaluated using 45 historical rainfall data that triggered debris flows, which is equal to 37.85 % and 11.1 %. Due to the two functions, the ID threshold curve can regularly move in the I-D coordinate system rather than a conventional threshold curve stay the same regardless of AEP variation, it is beneficial to improve the prediction capacity of the ID threshold.

ObjectivesUntil now, there have been few tools to evaluate whether a surgeon was technically ready to perform a safe pancreaticojejunostomy (PJ). In the current study, we aimed to evaluate whether a three-dimensional model could mimic a real surgical situation and distinguish between surgeons of different levels of experiences.DesignA three-dimensional PJ dry laboratory model was printed. Eight experienced pancreatic surgeons were tasked to evaluate the appearance and tactile sensation of the model. Proficiency was scored based on 15 surgeons with various levels of pancreatic experience performing a PJ on the three-dimensional model. Additionally, the time of manipulation and NASA Task Load Index (NASA-TLX) scores were recorded for each operation.SettingOur study was conducted in multimedical centre in China.ResultsCompared with real surgical situations, this model had similar appearance (3.96±0.55 out of five points) and tactile sensation (3.85±0.46 out of five points) according to the expert evaluation. Additionally, the chief surgeon group scored the best in proficiency (based on NASA-TLX scores and operative time), and there were statistical differences for performances among surgeons of various levels (p<0.05).ConclusionThe three-dimensional PJ model could mimic a real surgical situation and can distinguish between surgeons of different levels of experiences.

BACKGROUND Most of previous researches on anatomic resection (AR) in early hepatocellular carcinoma (HCC) were conducted in high-volume centres with controversial results. This study aims to provide evidence of the utilization of AR in early HCC at population level. METHODS The Surveillance, Epidemiology, and End Results 18 registries database (2004-2015) of the USA was utilized to identify early HCC cases ≤5 cm. Overall survival and cancer-specific survival were both analysed. RESULTS A total of 976 AR and 409 wedge resection (WR) cases were identified. For the post-operative (death within 1 month) and middle-term (death within 3 years) survival, effect of AR was found to be similar to that of WR after adjusting other covariates. However, for the long-term (death within 5 years) survival, the therapeutic effect of AR proved to be superior to that of WR (relative risk (RR) 0.655 for overall survival; RR 0.658 for cancer-specific survival, both P

Background This pioneering study is aimed to design training models for robotic pancreaticojejunostomy (PJ) and to assess their usefulness using quality improvement exercise in the dry lab. Methods Three dry lab models were developed including the anastomosis model of a transected silicon pancreatic stent (model 1), a rough model (model 2) simulating PJ, and an advanced three-dimensional printed model (model 3) more vividly simulating PJ. Three surgeons (A, B, C) with same specialty and levels of expertise in surgery were enrolled in the training which was divided into three rounds of tasks. In the first round, all three surgeons (A, B, C) participated in the training on basic technical tasks before moved on to the next rounds. While surgeons A, B participated in the second round on model 1, only surgeon A worked on model 2 in the third round. Their proficiency of performance was evaluated on model 3. Results The results of the first and second rounds between surgeons are similar. Surgeon A practiced with model 2 for 6 h, completing 10 cases. In model 3, the times of attempts before achieving a consecutively three times of satisfactory anastomosis procedures were compared, for surgeon A, six cases, 20 for B and 25 for C. Conclusions The specifically designed series of dry lab training models may be a potential training tool for advancing the robotic PJ through quality improvement exercise in dry lab. Further larger and well-designed studies are warranted to validate this issue.

The role of laparoscopic hepatectomy (LH) for intrahepatic cholangiocarcinoma (ICC) remains indefinite, though the utilization of this minimally invasive approach has been increasing for ICC. We herein performed a meta-analysis to investigate this issue.Six retrospective studies including 384 patients who had undergone LH and 2147 patients who had undergone open hepatectomy (OH) for ICC were included. The fixed-effects or random-effects models were utilized for data analysis.Compared with patients who had undergone OH for ICC, patients who had undergone LH for ICC experienced more R0 resections (81.6 versus 73.8%, risk ratio (RR) = 1.08, 95% confidence interval (CI) 1.02-1.14; P = 0.008) but less major hepatectomies (37.7 versus 54.2%, RR = 0.69, 95% CI 0.60-0.79; P 0.0001), less lymph node dissections (38.0 versus 61.5%, RR = 0.62, 95% CI 0.54-0.70; P 0.0001), and smaller tumor size resected (4.14 versus 4.94 cm, weighted mean difference = - 0.80 cm, 95% CI - 1.38 to - 0.22 cm; P = 0.007). No significant difference was observed in other perioperative results (all P 0.05) or overall survival (hazard ratio (HR) = 1.38, 95% CI 0.63-3.02; P = 0.43).LH has comparable safety, feasibility, and oncological efficacy to that of OH for ICC and has superiority in R0 resection over OH. It may be time to consider LH for ICC only if a more thorough effort on lymph node dissection is undertaken in selective patients at experienced centers.

Dazhou is one of the landslide-prone areas in southwest China. Since rainfall is the primary factor responsible for slope instability in this region, empirical rainfall thresholds may be effective for landslide warning. Thresholds using the intraday rainfall and the effective antecedent rainfall up to 7 days prior to landslide occurrence have been defined for this area. The study region was divided into 6 alert zones. For each zone, the daily rainfall and landslide data in the monsoon season during the period of 2003–2010 were analyzed, and the logistic regression method was employed to fit the dataset and provide diverse probability thresholds. Subsequently, the optimal threshold was identified by receiver operating characteristic (ROC) analysis. Furthermore, two classes of criteria and the associated indicators were used to determine the three rainfall thresholds for the warning model with four classes of alert (i.e., no warning, moderate warning, high warning, and very high warning). Finally, these thresholds were validated with dataset for the period 2011–2015. It suggests that the optimal threshold derived from ROC analysis, with the probability ranging from 4 to 10%, is suitable for issuing moderate warning, while the probability corresponding to the thresholds for high warning and very high warning varies in the ranges 30–55% and 75–95%, respectively. Performance of these thresholds in the period 2011–2015 is comparable to that in the period 2003–2010, indicating the robustness of them and the potential for practical use.

Laparoscopic approach for gallbladder cancer (GBC) has long been contraindicated, but few recent studies have demonstrated the oncologic outcomes of this treatment. The purpose of this study was to compare the perioperative outcomes and long-term survival for laparoscopic surgery versus traditional open surgery of GBC. Between January 2014 and December 2018, 63 GBC patients who received radical resection were enrolled in this study, with 32 patients in laparoscopic group and 31 cases in laparotomy group. Perioperative data and postoperative survival were retrospectively evaluated. Laparoscopic approach was associated with less intraoperative bleeding (267.20 ± 47.07 vs. 502.60 ± 69.70, P = 0.007), fewer postoperative days of oral diet recovery (2.34 ± 0.31 vs. 3.32 ± 0.35, P = 0.041), and hospital stay (11.03 ± 0.99 vs. 14.35 ± 1.11, P = 0.028). There were no significant differences between two groups regarding other perioperative outcomes. Patients in laparoscopic group showed better 1-year overall survival than those in laparotomy group (72.91% vs. 47.82%, P = 0.086). Subgroup analysis for GBC patients in T3 stages revealed that laparoscopic approach was associated with less intraoperative bleeding (268.00 ± 57.19 vs. 541.50 ± 101.30, P = 0.009), fewer postoperative days of hospital stay (9.87 ± 1.10 vs. 14.90 ± 1.53, P = 0.017), and improved 1-year overall survival (P = 0.023). Subgroup analysis for GBCs in TNM III and TNM IV stages showed comparable intraoperative parameters and postoperative survival between two groups. Laparoscopic surgery for GBCs may offer the comparable perioperative outcomes as conventional laparotomy procedure, and tend to be associated with less intraoperative bleeding, faster oral diet recovery, shorter hospital stay, and improved 1-year overall survival.

Long noncoding RNAs (lncRNAs) play important roles in regulating the development and progression of many cancers. However, the clinical significance of specific lncRNAs in the context of nasopharyngeal carcinoma (NPC) and the molecular mechanisms by which they regulate this form of cancer remain largely unclear. In this study we found that the lncRNA PVT1 was upregulated in NPC, and that in patients this upregulation was associated with reduced survival. RNA sequencing revealed that PVT1 was responsible for regulating NPC cell proliferation and for controlling a hypoxia-related phenotype in these cells. PVT1 knockdown reduced NPC cell proliferation, colony formation, and tumorigenesis in a subcutaneous mouse xenograft model systems. We further found that PVT1 serves as a scaffold for the chromatin modification factor KAT2A, which mediates histone 3 lysine 9 acetylation (H3K9), recruiting the nuclear receptor binding protein TIF1β to activate NF90 transcription, thereby increasing HIF-1α stability and promoting a malignant phenotype in NPC cells. Overexpression of NF90 or HIF-1α restored the proliferation in cells that had ceased proliferating due to PVT1 or KAT2A depletion. Conversely, overexpression of active KAT2A or TIF1β, but not of KAT2A acetyltransferase activity-deficient mutants or TIF1β isoforms lacking H3K9ac binding sites, promoted a PVT1-mediated increase in NF90 transcription, as well as increased HIF-1α stability and cell proliferation. PVT1 knockdown enhanced the radiosensitization effect in NPC cells via inhibiting binding between H3K9ac and TIF1β in a manner. Taken together, our results demonstrate that PVT1 serves an oncogenic role and plays an important role in radiosensitivity in malignant NPC via activating the KAT2A acetyltransferase and stabilizing HIF-1α.

The herringbone water-sediment separation structure (HWSSS) was developed to prevent debris flows. This paper mainly focuses on evaluating the sediment separation efficiency of HWSSS in debris flow prevention and determining the grid opening width D, a crucial structure parameter for HWSSS design. Theoretical analysis on the total sediment separation rate Pt reveals that the efficiency of sediment separation is much related with sediment grain size distribution (GSD) and grid opening width. The lower limit of Pt is deduced from the perspective of safety consideration by transforming debris flow into sediment-laden flow. Hydraulic model tests were carried out. Based on the regression analysis of the experimental data, the quantitative relationships between Pt and D and GSD characteristic values were finally established. A procedure for determining optimal grid opening width is proposed based on these analyses. These results are of significance in evaluating sediment separation effect by HWSSS in debris flow prevention and contribute to a more explicit methodology for design of HWSSS.

The role of single-incision laparoscopic cholecystectomy (SILC) and single-incision robotic cholecystectomy (SIRC) is still unclear. We update the summarization of the feasibility and safety of SILC and SIRC. A comprehensive search of SILC and SIRC of English literature published on PubMed database between January 2015 and November 2020 was performed. A total of 70 articles were included: 41 covering SILC alone, 21 showing SIRC alone, 7 reporting both, and 1 study not specified. In total, 7828 cases were recorded (SILC/SIRC/not specified, 6234/1544/50); and the gender of 7423 cases was definitively reported: the female rate was 64.0% (SILC/SIRC/not specified, 62.1%/71.5%/74.0%). The weighted mean for body mass index (BMI), operative time, blood loss and post-operative hospital stay was 25.5 kg/m2 (SILC/SIRC, 25.0/27.0 kg/m2), 73.8 min (SILC/SIRC, 68.2/88.8 min), 12.6 mL (SILC/SIRC, 12.1/14.8 mL) and 2.5 days (SILC/SIRC, 2.8/1.9 days), respectively. The pooled prevalence of an additional port, conversion to open surgery, post-operative complications, intraoperative biliary injury, and incisional hernia was 4.1% (SILC/SIRC, 4.7%/1.9%), 0.9% (SILC/SIRC, 0.7%/1.5%), 5.9% (SILC/SIRC, 6.2%/4.1%), 0.1% (SILC/SIRC, 0.2%/0.09%), and 2.1% (SILC/SIRC, 1.4%/4.8%), respectively. Compared with conventional laparoscopic cholecystectomy, SIRC has experienced more postoperative incisional hernias (risk difference = 0.05, 95% confidence interval 0.02–0.07; P

Background: Gallbladder neuroendocrine carcinomas (GB-NECs) are a group of rare and heterogeneous neoplasms. There are few reports regarding laparoscopic surgery for GB-NEC cases diagnosed at advanced stage.Case presentation: Three patients, two females and one male, were admitted to our hospital. Two patients had the chief complaint of upper quadrant pain and one patient was found to have gallbladder occupation during a routine health checkup. No patient complained jaundice, weight loss, or carcinoid syndrome-related symptoms including diarrhea, edema, flushing and wheezing. Contrast-enhanced computed tomography (CT) examination showed local wall thickening of the gallbladder. In addition, one patient showed focal liver parenchymal invasion, and none of the three patients' preoperative imaging examination revealed lymph nodes (LNs) metastases. All three patients underwent laparoscopic radical cholecystectomy according to intraoperative frozen pathological examination, and they were diagnosed as GB-NEC based on postoperative pathology and immunohistochemistry. TNM stages of these patients were ⅢA (T3N0M0), ⅢB (T3N1M0) and ⅣB (T3N2M0), respectively. Chromogranin A (CgA) and synaptophysin (Syn) were positive in all cases. No patient encountered postoperative bleeding, bile leakage, abdominal abscess, gastrointestinal fistulas or pulmonary complication. Two patients underwent postoperative chemotherapy with two cycles and seven cycles of etoposide plus cisplatin, respectively. Another patient did not receive postoperative chemotherapy due to his poor general condition. The overall survival time of three patients was 4.6 months, 16.8 months and 8.5 months, respectively. All three patients presented with liver and/or bile duct recurrence after surgery with the tumor-free survival time of 2.3 months, 3.3 months and 3.0 months, respectively.Conclusion: Laparoscopic surgery may be considered as a potential treatment for advanced GB-NEC in selected patients. However, further studies are needed to investigate the tumor-free survival benefit of laparoscopic surgery, and whether expanding the resection scope could reduce postoperative recurrence.

A slope unit is commonly used as calculation unit for regional landslide analysis. However, the capacity of the slope unit to reflect the geomorphological features of actual landslides still needs to be verified. This is because such accurate representation is critical to ensure the physical meaning of results from subsequent landslide stability analysis. This paper presents work conducted on landslides and slope extraction in two areas in China: The Jiangjia Gully area (Yunnan Province) and Fengjie County (Chongqing Municipality). Ground-based light detection and ranging (LiDAR) data are combined with field landslide terrace measurements to allow for the comparison of slope unit extraction methods (conventional vs. MIA-HSU) in terms of their ability to reflect the geomorphological features of shallow and deep-seated landslides. The results indicate that slope unit boundaries extracted by the conventional method do not match the geomorphological variations of actual landslides, and the method is therefore deficient in meaningfully extracting slope units for further landslide analysis. By contrast, slope units obtained using the MIA-HSU method accurately reflects the geomorphological features of both shallow and deep-seated landslides, and thus provides clearer geomorphological meaning and more reasonable calculation units for regional landslide assessment and prediction.

Background The role of laparoscopic surgery (Lap) and robotic surgery (Rob) for radical resection of hilar cholangiocarcinoma (HC) is not clear. We summarized the safety and feasibility of Lap and Rob for HC. Methods A search of all HC studies in English published on PubMed up to April 2020 was conducted. References from retrieved articles were reviewed to broaden the search. Results In total, 23 reports were enrolled: 15 involving Lap, seven using Rob and one study reporting a minimally invasive approach (Lap or Rob, not specified). A total of 205 cases of HC were documented (Lap/Rob/not specified, 99/101/5): 37 cases of Bismuth type-I (Lap/Rob, 17/20), 22 cases of Bismuth type-II (Lap/Rob, 15/7), 68 cases of type-III (Lap/Rob, 39/29) and 13 cases of type-IV (Lap/Rob, 9/4). The pooled prevalence of R0 resection was 80.1% (Lap/Rob, 85.9%/71.0%). The weighted mean for operative time, blood loss and post-operative hospital stay was 458.4 min (Lap/Rob, 423.3/660.8 min), 615.3 mL (Lap/Rob, 521.0/1188.5 mL) and 14.0 days (Lap/Rob, 14.0/13.7 days), respectively. The pooled prevalence of conversion to open surgery, post-operative complications, and perioperative mortality was 9.1% (Lap/Rob, 12.2%/3.8%), 47.2% (Lap/Rob, 38.4%/61.3%) and 3.0% (Lap/Rob, 4.0%/2.0%), respectively. Conclusion With innovations in technology and gradual accumulation of surgical experience, the feasibility and safety of performing Lap and Rob for HC will improve.