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Simple Summary: Radical pancreatectomies with superior mesenteric vein (SMV) resection without portal-to-superior mesenteric vein (PV/SMV) reconstruction are scarcely discussed in the literature. The existing data contain around 15 cases published with unclear oncological results and algorithms of patients' selection. In the present report, we analyzed the short- and long-term results of 19 consecutive pancreatectomies with SMV resection without PV/SMV reconstruction for locally advanced pancreatic ductal adenocarcinoma, and discussed the role of CT-based preoperative reconstructions and selection criteria for radical and safe surgery in this highly specific group of patients. The "vein definition" for locally advanced pancreatic ductal adenocarcinoma (LA PDAC) assumes portal-to-superior mesenteric vein (PV/SMV) unreconstructability due to tumor involvement or occlusion. Radical pancreatectomies with SMV resection without PV/SMV reconstruction are scarcely discussed in the literature. Retrospective analysis of 19 radical pancreatectomies for "low" LA PDAC with SMV and all its tributaries resection without PV/SMV reconstruction has shown zero mortality; overall morbidity—56%; Dindo–Clavien—3–10.5%; R0—rate—82%; mean operative procedure time—355 ± 154 min; mean blood loss—330 ± 170 mL; delayed gastric emptying—25%; and clinically relevant postoperative pancreatic fistula—8%. In three cases, surgery was associated with superior mesenteric (n2) and common hepatic artery (n1) resection. Surgery was completed without vein reconstruction (n13) and with inferior mesenteric-to-splenic anastomosis (n6). There were no cases of liver, gastric, or intestinal ischemia. A specific complication of the SMV resection without reconstruction was 2–3 days-long intestinal edema (48%). Median overall survival was 25 months, and median progression-free survival was 18 months. All the relapses, except two, were distant. The possibility of successful SMV resection without PV/SMV reconstruction can be predicted before surgery by CT-based reconstructions. The mandatory anatomical conditions for the procedure were as follows: (1) preserved SMV-SV confluence; (2) occluded SMV for any reason (tumor or thrombus); (3) well-developed inferior mesenteric vein collaterals with dilated intestinal veins; (4) no right-sided vein collaterals; and (5) no varices in the upper abdomen. Conclusion: "Low" LA PDACs involving SMV with all its tributaries can be radically and safely resected in highly and specifically selected cases without PV/SMV reconstruction with an acceptable survival rate. [ABSTRACT FROM AUTHOR]

The key challenge of cell-free tumor DNA (cftDNA) analysis in pancreatic ductal adenocarcinoma (PDAC) is overcoming its low detection rate, which is mainly explained by the overall scarcity of this biomarker in plasma. Obstructive jaundice is a frequent event in PDAC, which enables bile collection as a part of routine treatment. The aim of this study was to evaluate the performance of KRAS-mutated cftDNA detection-based liquid biopsy of plasma and bile in patients with pancreatic neoplasms using digital droplet PCR. The study included healthy volunteers (n = 38), patients with PDAC (n = 95, of which 20 had obstructive jaundice) and other pancreatic neoplasms (OPN) (n = 18). The sensitivity and specificity compared to the control group were 61% and 100% (AUC-ROC—0.805), and compared to the OPN group, they were 61% and 94% (AUC-ROC—0.794), respectively. Bile exhibited higher cftDNA levels than plasma (248.6 [6.743; 1068] vs. 3.26 [0; 19.225] copies/mL) and a two-fold higher detection rate (p < 0.01). Plasma cftDNA levels were associated with distant metastases, tumor size, and CA 19-9 (p < 0.05). The probability of survival was worse in patients with higher levels of cftDNA in plasma (hazard ratio—2.4; 95% CI: 1.3–4.6; p = 0.005) but not in bile (p > 0.05). Bile is a promising alternative to plasma in patients with obstructive jaundice, at least for the diagnostic purposes of liquid biopsy. [ABSTRACT FROM AUTHOR]

A two stage real-time hand gesture recognition system is presented. It combines a machine learning trained detection step with a colour processing contour shape validation step. The detection step is done with either Adaboost Cascades or Support Vector Machines using HOG features. The system achieves a low false positive rate and a sufficient true positive rate necessary for robust real-time performance. It performs well compared to MobileNets a state of the art Neural Network for mobile real-time applications. [ABSTRACT FROM AUTHOR]

In the Internet of things, many data transfer protocols are used for various tasks. In this article, we consider the application layer protocols that are the main ones for transmitting messages in the IoT. The main problems are unpredictability, lack of stability of data transmission delays, and non-determinism, which are also important for real-time systems. The purpose of this study is to determine the most appropriate middleware and data transfer protocol for systems with high data transfer requirements, including real-time systems. Therefore, MQTT, RTPS, JMS, and AMQP protocols were analyzed in order to find out what tasks these protocols should be used for and whether they can be used in robotic and autonomous systems where high data transmission requirements are imposed. To evaluate the protocols, the standards were analyzed to determine the pros and cons, and the software implementations of each of them were selected. To assess the characteristics of data transmission, we have developed our own test scenarios that simulate complex situations. The behavior of software solutions is analyzed and a comparative analysis is made based on the obtained data. Together, the theoretical analysis of protocols and the study of software solutions allow us to conclude on the applicability of a particular protocol in real-time systems. As a result of the study, we can conclude that RTPS is the best solution for real-time systems with different traffic and MQTT performs well when transmitting short messages. But none of the protocols under consideration guarantees the determinism of data transmission, so it is better to use specialized link-layer protocols to obtain guarantees. [ABSTRACT FROM AUTHOR]

This study looked at the thermal conductivity of translucent (Y1−xGdx)2O3 (where 0 ≤ x ≤ 1) solid solution ceramics in the temperature range from 50 K to 300 K. The samples were obtained by hot pressing from high-purity nanopowders at 1600 °C, no sintering additives were used. Compositions with cubic syngony (x ≤ 0.7) and a monoclinic one (x ≥ 0.9) were investigated. Furthermore, a dense sample of cubic Gd2O3 with a LiF sintering additive was obtained and its thermal conductivity was determined (k = 11.7 W/(m K) at 300 K). It was shown that in the range of solid solution ceramic compositions 0.2 ≤ x ≤ 0.7, the thermal conductivity was practically unchanged and close to the value k ≈ 5 W/(m K) at 300 K. [ABSTRACT FROM AUTHOR]

This work addresses a shortcoming of the beta distribution when applied to assumed probability density function (PDF) methods for reactive flow, such as the flamelet-progress variable method. Regardless of parameter values, the beta distribution contains the entire sample space of a conserved scalar, which can be shown to violate the strong maximum principle of partial differential equations. To remedy this, a new class of probability distributions is introduced and tested on several conserved scalar mixing problems. The new distributions do not violate the strong maximum principle, and are in better quantitative agreement with transported PDF and DNS solutions than the beta distribution. The effects of filter width and residence time are examined, and extensions to multiple mixture fractions are outlined. [ABSTRACT FROM AUTHOR]

The combustion stability of a liquid-propellant rocket engine experiencing a random, finite perturbation from steady-state conditions is examined. The probability is estimated for a nonlinear resonant limit-cycle oscillation to be triggered by a random disturbance. Transverse pressure waves are considered by using a previously published two-dimensional nonlinear pressure wave equation coupled with Euler equations governing the velocity components. The cylindrical combustion chamber is a complex system containing multiple co-axial methane–oxygen injectors; each co-axial jet is analysed for mixing and burning on its own local grid scheme, with the energy release rate coupled to the wave oscillation on the more global grid. Two types of stochastic forcing for the random disturbance are explored: a travelling Gaussian pressure pulse and an oscillating pressure dipole source. The random variables describing the pulse are magnitude, location, duration and orientation of the disturbances. The polynomial chaos expansion (PCE) method is used to determine the long-time behaviour and infer the asymptote of the solution to the governing partial differential equations. Depending on the random disturbance, the asymptote could be the steady-state solution or a limit-cycle oscillation, e.g. a first tangential travelling wave mode. The asymptotic outcome is cast as a stochastic variable which is determined as a function of input random variables. The accuracy of the PCE application is compared with a Monte Carlo calculation and is shown to be significantly less costly for similar accuracy. [ABSTRACT FROM PUBLISHER]

This chapter offers the first full translation from Russian to English of the Balance of the National Economy of the USSR, 1924-26's first chapter. Involving 12 authors and composed of 21 chapters, the Balance is a collective work published in June 1926 in Moscow by the Soviet Central Statistical Administration under the scientific supervision of its former director, Pavel Illich Popov (1872-1950). In this first chapter, titled 'Studying the Balance of the National Economy: An Introduction', Popov set the theoretical foundations of what might be considered as the first modern national accounting system and paved the way to multi-sector macroeconometric modelling. [ABSTRACT FROM AUTHOR]

Simple Summary: Distal pancreatectomy with the celiac artery resection (DPCAR) is an oncologically justified procedure for locally advanced pancreatic ductal adenocarcinoma (PDAC). The results of its use in our selective group of 40 consecutive patients demonstrated a high rate of R0-resections, acceptable morbidity, and survival better than that for resectable PDAC. The unsolved problems of this procedure are the liver and stomach ischemic complications, which can be lethal or lead to prolonged hospital stay and deterioration in survival. The existing clinical data do not explain the mechanisms of these specific complications in sufficient detail and can't be used for their prognosis and prevention. We have studied the correlation of clinical data and hemodynamic changes of the collateral arteries in a series of technically homogeneous procedures. The geometrical changes of the pancreatoduodenal arcade elements after DPCAR could explain the causes of ischemic complications after surgery and determine the directions for their prevention. DPCAR's short- and long-term outcomes are highly diverse, while the causes and prevention of ischemic complications are unclear. To assess oncological, surgical, and hemodynamic outcomes of 40 consecutive DPCARs for pancreatic (n37) and gastric tumors (n3) (2009–2021), retrospective analyses of mortality, morbidity, survival, and hemodynamic consequences after DPCAR were undertaken using case history data, IOUS, and pre- and postoperative CT measurements. In postoperative complications (42.5%), the pancreatic fistula was the most frequent event (27%), 90-day mortality was 7.5. With 27 months median follow-up, median overall (OS) and progression-free survival (PFS) for PDAC were 29 and 18 months, respectively; with 1-, 3-, and 5-years, the OS were 90, 60, and 28%, with an R0-resection rate of 92.5%. Liver and gastric ischemia developed in 0 and 5 (12.5%) cases. Comparison of clinical and vascular geometry data revealed fast adaptation of collateral circulation, insignificant changes in proper hepatic artery diameter, and high risk of ischemic gastropathy if the preoperative diameter of pancreaticoduodenal artery was <2 mm. DP CAR can be performed with acceptable morbidity and survival. OS and RFS in this super-selective cohort were compared to those for resectable cancer. The changes in the postoperative arterial geometry could explain the causes of ischemic complications and determine directions for their prevention. [ABSTRACT FROM AUTHOR]

A variety of Er3+-, Tm3+-, and Yb3+-activated CaF2-, SrF2-, (Ca, Sr)F2- and (Sr, Ba)F2-based fluoride laser ceramics have been prepared by the hot-forming technique. Lasing of the SrF2:Yb3+, (Ca, Sr)F2:Er3+, (Ca, Sr)F2:Tm3+, (Ba, Sr)F2:Tm3+ and (Ba, Sr)F2:Yb3+ specimens with diode pumping has been observed for the first time. Thermal conductivity data for the above fluorite-type laser materials are also presented and discussed. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We describe a new family of weak pth order accurate SDE time integration schemes, called the direct Richardson pth order accurate (DRp) schemes. The DRp schemes use the idea of Richardson extrapolation on Euler time steps, performed by way of an acceptance-rejection algorithm. Previous applications of Richardson extrapolation to the Euler scheme are applicable only when the objective is to estimate a functional of the final distribution of the process. In contrast, provided that the diffusion matrix is strictly positive definite, the DRp class of schemes can be used in all applications which require a weak SDE time integration scheme. Numerical results have been obtained, and a comparison is made between the second- and third-order accurate DRp schemes and other modern SDE time integration schemes, indicating that the DRp schemes incur less error than standard algorithms based on Ito-Taylor expansions, and have similar computational efficiency. Finally, we provide a proof of the convergence properties of the DRp schemes. [ABSTRACT FROM AUTHOR]

Due to the fact that the application of AW and EP additives in low-temperature greases may lead to worse high-temperature and anti-corrosion characteristics as well as additional burden on the environment due to the content of aggressive components, in this paper, the possibility of replacing these additives with NFA, which do not have these disadvantages, was investigated. The analysis of nanosized particles being used as functional additives in greases was carried out. The morphology of the following nanoparticles was studied: montmorillonite K 10, silica, calcium car-bonate and borate, halloysite, and molybdenum disulfide incorporated in halloysite tubes. The effect of nanostructured components on the physicochemical characteristics and anti-wear and anti-scuffing properties of complex lithium, polyurea, and polymer greases were studied. Maximal improvement of anti-wear and anti-scuffing characteristics of cLi-greases was reached when using silica and calcium borate. Maximal improvement of anti-scuffing properties of PU-lubricant was reached when using calcium carbonate and the two-component NFA based on halloysite, for anti-wear properties when adding silicon dioxide and halloysite. When the concentrations of silicon dioxide and calcium carbonate was increased from 1 to 3 wt.%, there was a decrease in yield stress of the structural frame of the PU-lubricant and its colloidal stability was worse. The increase of the concentration of calcium carbonate and borate nanoparticles in the studied range led to a significant improvement of the anti-wear and anti-scuffing characteristics of the PU grease, respectively. The greases properties' dependence from the nanostructured functional additives' introduction method and their concentration were investigated. Nanoparticles were added into the test lubricants before and after the thermo-mechanical dispersion stage. The addition of silicon dioxide and calcium carbonate NFA after the heat treatment stage led to worsening of the characteristics of the plastic material, and the increase of their concentration from 1 to 3 wt.% formed a harder structure of Li-grease. On the contrary, the addition of calcium borate NFA is recommended after the thermomechanical dispersion. The choice of nanoparticles and the method of their addition to the lubricants of various types was carried out according to the results of the previous stage of the research. Along with the analysis of the physicochemical characteristics and anti-wear and anti-scuffing properties of the lubricants, the structure of the dispersion phase of nanomodified lubricants were studied. [ABSTRACT FROM AUTHOR]

The chaotic synchronization of two electron-wave media with interacting backward waves and cubic phase nonlinearity is investigated in the paper. To detect the chaotic synchronization regime we use a new approach, the so-called time scale synchronization [Chaos 14, 603–610 (2004)]. This approach is based on the consideration of the infinite set of chaotic signals’ phases introduced by means of continuous wavelet transform. The complex space–time dynamics of the active media and mechanisms of the time scale synchronization appearance are considered. [ABSTRACT FROM AUTHOR]

Bulk c-oriented CeF3 single crystals (sp. gr. P 3 ¯ c 1 ) were grown successfully by the vertical Bridgman technique in a fluorinating atmosphere. A description of the crystal growth procedure and the solution of the difficulties during the growth process are presented in detail. The anisotropy of the mechanical, thermal and electrophysical properties were studied for the first time. The maximum values of the thermal conductivity coefficient (α = 2.51 ± 0.12 W·m−1·K−1) and the ionic conductivity (σdc = 2.7 × 10−6 S/cm) at room temperature are observed in the [0001] direction for the CeF3 crystals. The Vickers (HV) and Berkovich (HB) microhardnesses for the (0001) , (10 1 ¯ 0) and (11 2 ¯ 0) crystallographic planes were investigated. The HB values were higher than the HV ones and decreased from 3.8 to 2.9 GPa with an increase in the load in the range of 0.5–0.98 N for the hardest (0001) plane. The { 11 2 ¯ 0 } , { 10 1 ¯ 0 } and { 0001 } cleavage planes were observed during the indentation process of the CeF3 crystals. The variability of Young's, the shear modules and Poisson's ratio were analyzed. A significant correlation between the shapes of the Vickers indentation patterns with Young's modulus anisotropy was found. The relationship between the anisotropy of the studied properties and the features of the CeF3 trigonal crystal structure is discussed. [ABSTRACT FROM AUTHOR]

Cubic KR3F10 (R = Y, Tb) single crystals have been successfully grown using the Bridgman technique. Growth of crystals of this type is complicated due to the hygroscopicity of potassium fluoride and melt overheating. The solution to the problem of oxygen-incorporated impurities has been demonstrated through the utilization of potassium hydrofluoride as a precursor. In this study, the crystal quality, structure features, and optical, thermal and electrophysical properties of KR3F10 were examined. Data on the temperature dependences of conductivity properties of KTb3F10 crystals were obtained for the first time. These crystals indicated thermal conductivity equal to 1.54 ± 0.05 Wm−1K−1 at room temperature caused by strong phonon scattering in the Tb-based crystal lattice. Ionic conductivities of KY3F10 and KTb3F10 single crystals were 4.9 × 10−8 and 1.2 × 10−10 S/cm at 500 K, respectively, and the observed difference was determined by the activation enthalpy of F− ion migration. Comparison of the physical properties of the grown KR3F10 crystals with the closest crystalline analog from the family of Na0.5−xR0.5+xF2+2x (R = Tb, Y) cubic solid solutions is reported. [ABSTRACT FROM AUTHOR]

ScF3 optical quality bulk crystals of the ReO3 structure type (space group P m 3 ¯ m , a = 4.01401(3) Å) have been grown from the melt by Bridgman technique, in fluorinating atmosphere for the first time. Aiming to substantially reduce vaporization losses during the growth process graphite crucibles were designed. The crystal quality, optical, mechanical, thermal and electrophysical properties were studied. Novel ScF3 crystals refer to the low-refractive-index (nD = 1.400(1)) optical materials with high transparency in the visible and IR spectral region up to 8.7 µm. The Vickers hardness of ScF3 (HV ~ 2.6 GPa) is substantially higher than that of CaF2 and LaF3 crystals. ScF3 crystals possess unique high thermal conductivity (k = 9.6 Wm−1К−1 at 300 K) and low ionic conductivity (σ = 4 × 10−8 Scm−1 at 673 К) cause to the structural defects in the fluorine sublattice. [ABSTRACT FROM AUTHOR]