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In this work, the dual effect of Na in the copper indium gallium diselenide (CIGS) absorber is studied. Na doping exhibits a drastic improvement of the cell efficiency mainly by an increase in the open‐circuit current and fill factor. However, when the Na content is too high, it can deteriorate the cell properties and performance. Nonetheless, it is still beneficial when compared with a cell without Na inside. Here, we therefore use electron backscatter diffraction, atom probe tomography, and admittance spectroscopy to understand why Na starts to deteriorate the properties when inserted excessively. More exactly, it is shown that a moderate addition of Na strongly decreases the open‐circuit voltage (VOC) deficit, whereas the opposite happens when the Na content is too high. Interestingly, this cell with deteriorated VOC value and characterized by a very high Na content exhibits a high density of not only grain boundaries and dislocations but also of Na‐rich clusters. These clusters may host a high concentration of deep defects and trap the electrons within the CIGS bulk. At this stage, Na still has its beneficial effects, but the cell properties start to deteriorate compared to the cell with a moderate content of Na, especially when found as clusters in the bulk. In conclusion, this work clearly demonstrates the dual effect of Na in the CIGS absorber. [ABSTRACT FROM AUTHOR]

Unmanned underwater vehicles which use biomimetic mechanisms are becoming increasingly useful in the realisation of tasks requiring silent and efficient propulsion. Complex fish kinematics are simplified to some extent and implemented in such vehicles. One of the essential fish behaviours is their ability to adjust their buoyancy using a swim bladder. This paper covers the issues concerning the implementation of artificial swim bladders as well as depth regulators in two underwater vehicles: biomimetic and hybrid. The control of vehicle depth through buoyancy change was examined in the computer simulation and in the experiment. Two types of artificial swim bladder were tested – a rigid cylinder with a piston and an elastic container with a water pump.

In liver transplantation, a side-to-side anastomosis is one of the commonly performed techniques of the inferior vena cava reconstruction. The authors report a case of an application of an endoscopic vascular linear stapler for a side-to-side caval anastomosis during deceased-donor liver transplantation. The back table procedure was performed in a standard fashion for a side-to-side anastomosis. The linear vascular stapler was introduced during the temporary clamping of the recipient's inferior vena cava and the anastomosis was created without problems. Suturing of the resulting defect completed the anastomosis. The use of the stapler resulted in a shortening of the anastomosis time. The staple line after the reperfusion of the graft was completely sealed. The patient's postoperative course was uncomplicated and post-operative ultrasound and computed tomography confirmed the patency of the anastomosis. This case demonstrates a novel approach to a side-to-side caval reconstruction during liver transplantation that enables a shortening of the implantation time and may improve the quality of anastomoses. [ABSTRACT FROM AUTHOR]

Skin autofluorescence (SAF) can detect advanced glycation end products (AGEs) that accumulate in tissues over time. AGEs reflect patients' general health, and their pathological accumulation has been associated with various diseases. This study aimed to determine whether its measurements can correlate with the liver parenchyma quality. This prospective study included 186 patients who underwent liver resections. Liver fibrosis and/or steatosis > 10% were found in almost 30% of the patients. ROC analysis for SAF revealed the optimal cutoff point of 2.4 AU as an independent predictor for macrovesicular steatosis ≥ 10% with an AUC of 0.629 (95% CI 0.538–0.721, p = 0.006), 59.9% sensitivity, 62.4% specificity, and positive (PPV) and negative (NPV) predictive values of 45.7% and 74.1%, respectively. The optimal cutoff point for liver fibrosis was 2.3 AU with an AUC of 0.613 (95% CI 0.519–0.708, p = 0.018), 67.3% sensitivity, 55.2% specificity, and PPV and NPV of 37.1% and 81.2%, respectively. In the multivariable logistic regression model, SAF ≥ 2.4 AU (OR 2.16; 95% CI 1.05–4.43; p = 0.036) and BMI (OR 1.21; 95% CI 1.10–1.33, p < 0.001) were independent predictors of macrovesicular steatosis ≥ 10%. SAF may enhance the available non-invasive methods of detecting hepatic steatosis and fibrosis in patients prior to liver resection. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text Objective: To compare the early results of mass and layered closure of upper abdominal transverse incisions. Summary of Background Data: Contrary to midline incisions, data on closure of transverse abdominal incisions are lacking. Methods: This is the first analysis of a randomized controlled trial primarily designed to compare mass with layered closure of transverse incisions with respect to incisional hernias. Patients undergoing laparotomy through upper abdominal transverse incisions were randomized to either mass or layered closure with continuous sutures. Incisional surgical site infection (incisional-SSI) was the primary end-point. Secondary end-points comprised suture-to-wound length ratio (SWLR), closure duration, and fascial dehiscence (clinicatrials.gov NCT03561727). Results: A total of 268 patients were randomized to either mass (n=134) or layered (n=134) closure. Incisional-SSIs occurred in 24 (17.9%) and 8 (6.0%) patients after mass and layered closure, respectively (P =0.004), with crude odds ratio (OR) of 0.29 [95% confidence interval (95% CI) 0.13–0.67; P =0.004]. Layered technique was independently associated with fewer incisional-SSIs (OR: 0.29; 95% CI 0.12–0.69; P =0.005). The number needed to treat, absolute, and relative risk reduction for layered technique in reducing incisional-SSIs were 8.4 patients, 11.9%, and 66.5%, respectively. Dehiscence occurred in one (0.8%) patient after layered closure and in two (1.5%) patients after mass closure (P >0.999). Median SWLR were 8.1 and 5.6 (P <0.001) with median closure times of 27.5 and 25.0 minutes (P =0.044) for layered and mass closures, respectively. Conclusions: Layered closure of upper abdominal transverse incisions should be preferred due to lower risk of incisional-SSIs and higher SWLR, despite clinically irrelevant longer duration. [ABSTRACT FROM AUTHOR]

This paper conveys some of the results of a research project involving the design and tests of biomimetic underwater vehicle which is intended for implementation of intelligence, surveillance and reconnaissance tasks. The research presented in this paper is based on the theoretical and practical study. All major subsystems of the robot are specified and briefly described. The mechanical design is based on modular structure. Two types of modules, dry and wet, are specified. The major parts of the tail module were checked with the use of the finite element method. Moreover, hardware and software parts of robot's control subsystem and Simulink model of static depth regulator are briefly presented. The final part presents main parameters and basic functionality of the built biomimetic underwater vehicle. [ABSTRACT FROM AUTHOR]

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This paper presents a mathematical model of the heat and mass transfer processes for a rotary-spray honey dehydrator with a heat pump and a closed air circuit. An analytical calculation model, based on the energy balance equations of the dehydrator and heat pump, was used to model the transient dehydration process of honey in a dehydrator. The presented article includes a different approach to modelling both the dryer and the heat pump assisting the drying process. The novel quality of this study lies in the use of original equations to determine the heat and mass transfer coefficients between honey and air and using an actual model of a cooling unit to model the honey dehydration process. The experimentally verified calculation algorithm enables an analysis of the effects of air flow rate, mixer rotation speed, and cooling unit power on the efficiency of the drying process. The dehydrator calculation model was used to minimize the drying time by selecting the optimal evaporative temperature values of the cooling unit. For fixed mixer speed and air flow rates, optimal values of evaporation temperatures allow for 8–13% reduction in honey drying time and an increase in the specific moisture extraction rate (SMER) by 4–32%. [ABSTRACT FROM AUTHOR]

The use of the Pringle maneuver (PM) varies widely among surgical departments. Its use depends on the operator and type of liver resection. The aim of this study was to determine the impact of the PM on patient outcomes when undergoing major liver resections. This retrospective study comprised 179 colorectal liver metastasis patients from two liver centers from Leeds and Warsaw. Only right or right extended hepatectomies with negative oncological margins were included. The primary outcome measure was the 5-year overall survival (OS). The PM was applied during 60 (33.5%) major hepatectomies included in the study and was associated with a higher peak 3-day postoperative bilirubin concentration (p = 0.002), yet not with the peak 3-day alanine aminotransferase activity (p = 0.415). The 5-year OS after liver resections with the PM and without the PM were 55.0% and 33.4%, respectively (p = 0.019). Following stratification by the Tumor Burden Score, after resections with the use of the PM, superior survival was particularly found in the subgroup of patients at intermediate risk of recurrence (p = 0.004). However, the use of the PM had no significant effect on the 5-year overall survival following adjustment for the confounding effect of the carcinoembryonic antigen concentration (p = 0.265). The use of the PM had no negative effects on the long-term outcomes in patients undergoing major, oncologically radical liver resections for colorectal metastases. [ABSTRACT FROM AUTHOR]

Thin‐film solar cells based on Cu(In,Ga)Se2 (CIGSe) absorber layers reach conversion efficiencies of above 20%. One key to this success is the incorporation of alkali metals, such as Na and K, into the surface and the volume of the CIGSe thin film. The present work discusses the impact of Na and K on the grain‐boundary (GB) properties in CIGSe thin films, i.e., on the barriers for charge carriers, Φb, and on the recombination velocities at the GBs, sGB. First, the physics connected with these two quantities as well as their impact on the device performance are revised, and then the values for the barrier heights and recombination velocities are provided from the literature. The sGB values are measured by means of a cathodoluminescence analysis of Na‐/K‐free CIGSe layers as well as on CIGSe layers on Mo/sapphire substrates, which are submitted to only NaF or only KF postdeposition treatments. Overall, passivating effects on GBs by neither Na nor K can be confirmed. The GB recombination velocities seem to remain on the same order of magnitude, in average about 103–104 cm s−1, irrespective of whether CIGSe thin films are Na‐/K‐free or Na‐/K‐containing. [ABSTRACT FROM AUTHOR]

The aim of this retrospective observational study was to evaluate outcomes of patients with extremely advanced hepatocellular carcinoma (HCC) after liver transplantation. A total of 285 HCC patients after liver transplantation were screened for eligibility based on either intrahepatic dissemination (≥10 tumors) or macrovascular invasion. Tumor recurrence was the primary end-point. The study cohort comprised 26 patients. Median recurrence-free survival was 23.2 months with hepatitis B virus (HBV) infection (p = 0.038), higher AFP model score (p = 0.001), prolonged graft ischemia (p = 0.004), and younger donor age (p = 0.016) being significant risk factors. Median recurrence-free survival of HBV-negative and HBV-positive patients was 29.8 and 9.3 months, respectively (p = 0.053). In patients with macrovascular invasion, recurrence-free survival at 3 years was 46.3% with no specific predictors. Tumor size (p = 0.044), higher AFP model score (p = 0.019), prolonged graft ischemia (p = 0.016), and younger donor age (p = 0.041) were significant risk factors in patients with intrahepatic dissemination. Superior 3-year outcomes were observed in patients with intrahepatic dissemination and tumor size <3.5 cm (83.3%, p = 0.027) and HBV-negative patients with ischemia <9.7 h (85.7%, p = 0.028). In conclusion, patients with extremely advanced HCCs are remarkably heterogeneous with respect to their profile of tumor recurrence risk. This heterogeneity is largely driven by factors other than standard predictors of post-transplant HCC recurrence. [ABSTRACT FROM AUTHOR]

Hepatic epithelioid hemangioendothelioma (HEHE) is a rare vascular tumor with indolent behavior in terms of malignancy. The treatment of choice is either resection in the case of resectable lesions or liver transplantation (LT) for the disseminated intrahepatic form. The aim of this study was to investigate the outcomes of patients with HEHE treated by LT. There were 18 patients with HEHE who underwent LT between 2002 and 2018 included in this retrospective study. The study group was comprised of young recipients (median age of 39 years) and mainly women (15 of 18; 83.3%). Two recipients had concomitant tumors of epithelioid hemangioendothelioma in the liver and lungs prior to LT. The survival probability was calculated using the Kaplan-Meier estimator. According to histopathological data, none of the patients had a macrovascular invasion. In 4 patients (22.2%), the disease had spread to the hilar lymph nodes. The maximum diameter of the tumor in the studied group was 18 cm. The survival probability after 1, 5, and 15 years was 94.0%, 82.6%, and 41.3%, respectively. No disease recurrence was observed during a median follow-up of 65.9 months. Liver transplantation provides favorable outcomes for selected patients with a hepatic form of epithelioid hemangioendothelioma. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma is the primary liver tumor forming from the biliary epithelium. Two major subtypes of this disease are distinguished because of the initial location: the extra- and intrahepatic form. The latter disease is currently a controversial indication for liver transplant (LT). The aim of this study was to evaluate the outcomes of LT of patients with intrahepatic cholangiocarcinoma. Based on postoperative histopathologic examination of the explanted liver, 8 patients with intrahepatic cholangiocarcinoma were identified from all LT recipients in the period between 1994 and 2019 and included in this retrospective cohort study. Four of the patients received transplants with a preoperative diagnosis of hepatocellular carcinoma; the remaining tumors were incidental findings. Patient survival was the primary outcome measure. Six recipients had solitary lesion with a maximum tumor diameter of 6 cm. The median carbohydrate antigen 19-9 concentration prior to LT was 52.3 U/mL. The overall survival was 75.0%, 37.5%, and 25% after the first, third, and fifth year, respectively, with a median survival of 18 months. Age (P =.758), carbohydrate antigen 19-9 (P =.282), largest tumor size (P =.862), and the sum of the number of lesions and diameter of the largest tumor (P =.530) were not significantly associated with overall survival. Recurrence-free survival was 71.4% after 1 year and 28.6% after 3 and 5 years. Correspondingly, no significant predictors of worse recurrence-free survival were found. Intrahepatic cholangiocarcinoma remains associated with a very high risk of recurrence and dismal survival after LT irrespective of macroscopic disease burden. • Intrahepatic cholangiocarcinoma (iCCA) can occasionally be found in explanted livers either incidentally or as tumors suspected as hepatocellular carcinoma. • Without adjunctive therapies patients after liver transplant with iCCA are characterized by dismal survival. • Poor prognosis of patients with iCCA after liver transplant was irrespective of macroscopic disease burden in our study. [ABSTRACT FROM AUTHOR]

Selected patients with unresectable perihilar cholangiocarcinoma (p-CCA) are now considered as candidates for liver transplant, provided they fulfill a strict perioperative treatment and staging protocol. The aim of this study was to examine the outcomes of patients after liver transplant with incidental p-CCA found in the liver explants. A cohort of 10 patients with incidental p-CCA after liver transplant in the period between 1994 and 2019 was included in this retrospective analysis. All patients with this diagnosis were scheduled for transplant because of primary sclerosing cholangitis. The primary and secondary endpoints comprised patient's death and tumor recurrence, respectively, assessed over a 5-year postoperative period. Patient median age was 35 years (range, 32-42 years). Median size of the tumor was 3.0 cm (range, 2.5-4.0 cm). Five patients (50%) had metastases to local lymph nodes. Overall survival was 100%, 37.5%, and 18.8% after the first, third, and fifth postoperative year, respectively, with median survival of 21 months. Patient age (P =.827), R1 resection status (P =.144), tumor diameter (P =.432), and presence of lymph node metastases (P =.663) were not significantly associated with overall survival. Recurrence-free survival was 60.0% after the first postoperative year and 22.5% after the third and fifth postoperative years, with median recurrence-free survival of 13.6 months. No significant predictors of tumor recurrence were found. Incidental p-CCA in patients with primary sclerosing cholangitis undergoing liver transplant is associated with universally very high risk of postoperative tumor recurrence and short expected survival. • Incidental perihilar cholangiocarcinoma (p-CCA) in patients undergoing liver transplant is rare. • Patients with incidental p-CCA with primary sclerosing cholangitis undergoing liver transplant have very high risk of postoperative tumor recurrence and short expected survival. • Patients with primary sclerosing cholangitis undergoing liver transplant have 4.3% risk for incidental p-CCA. [ABSTRACT FROM AUTHOR]

Background: Data on routine hypothermic machine perfusion of livers procured from donors after brain death (DBD) are scarce, and the benefits of the method have only been demonstrated in extended criteria grafts. The aim of this study was to assess if end-ischemic dual hypothermic oxygenated machine perfusion (dHOPE) is superior to static cold storage (SCS) in preservation of livers procured from DBD donors with respect to long-term outcomes. Existing data on short-term outcomes favours dHOPE in patients receiving high-risk grafts., Methods: This prospective randomized controlled trial included 104 recipients of DBD livers randomly assigned to static cold storage arm (78 patients) and dHOPE arm (26 patients). Endpoints of interest were occurrence of biliary complications (biliary fistula, anastomotic, and nonanastomotic strictures) and overall patient (OS) and graft survival (GS) during two-year follow-up., Results: A total of 36 patients developed biliary complications (at least one event) - 6 events in dHOPE arm and 30 in SCS arm. There was no significant difference in biliary complications between groups (23.7% vs. 43.4% [P=0.11]). No differences were found significant with respect to anastomotic (19.9% vs. 33.7% [P=0.20]) and non-anastomotic strictures (0% vs. 11.1% [P=0.10]) as well as biliary fistulas (11.7% vs. 12.2% [P=0.93]). Survival analysis did not show significantly different result in the study population - OS: 92.3% in dHOPE and 83.9% in SCS (P=0.35), and GS: 92.3% and 81.4% (P=0.23), respectively. However, significant difference in GS was noted in recipients of high-risk grafts - 100% in dHOPE and 73.1% in SCS, respectively (P=0.038)., Conclusions: The long-term outcome data suggest that the routine use of dHOPE may be beneficial for recipients of high-risk grafts from DBD donors. The present study does not provide any evidence for benefits of dHOPE in low-risk grafts., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)