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We show that the matrix element of a local operator between hadronic states can be used to unambiguously define the associated spatial density. As an explicit example, we consider the charge density of a spinless particle and clarify its relationship to the electric form factor. Our results lead to an unconventional interpretation of the spatial densities of local operators and their moments.

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OBJECTIVES: To assess the outcomes of cavoatrial tumor thrombus removal using the liver transplantation technique for thrombectomy, a retrospective study was conducted. MATERIALS AND METHODS: Five patients with atrial tumor thrombi who underwent piggy-back mobilization of the liver, surgical access to the right atrium from the abdominal cavity, and external manual repositioning of the thrombus apex below the diaphragm (milking maneuver) were included into the study. Extracorporeal circulation was used in none of the cases. The average length of the atrial component of the tumor was 20.0 ± 11.7 mm (10 to 35 mm), and the width was 14.8 ± 8.5 mm (10 to 30 mm). In this work, the features of patients and surgical interventions as well as perioperative complications and mortality were analyzed. RESULTS: External manual repositioning of the tumor thrombus apex below the diaphragm was successfully performed in all patients. Tumor thrombi with the length of the atrial part up to 1.5 cm were removed through the extrapericardial approach. For evacuation of the thrombi with the large atrial part (3.0 cm or more), a transpericardial surgical approach was required. Specific complications associated with the access to the right atrium from the abdominal cavity (paresis of the right phrenic nerve, pneumothorax, and mediastinitis) were not detected in any case. The average clamping time of the supradiaphragmatic inferior vena cava (IVC) was 6.3 ± 4.6 min. The volume of intraoperative blood loss varied from 2500 to 5600 ml (an average of 3675 ± 1398.5 ml). CONCLUSION: Our work represents the initial experience in the liver transplantation technique for thrombectomy in distinct and well-selected patients with atrial tumor thrombi. The effectiveness of this approach needs further study. The video presentation of our research took place in March 2019 at the 34th Annual EAU Congress in Barcelona.

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In most cases RCC with venous extension is an indication for radical nephrectomy. However, in patients with imperative indications for nephron-sparing surgery a kidney resection with thrombectomy in rare situations is possible. We present a surgical technique for nephron-sparing surgery in patients with tumor spreading into the main renal vein. From 2007 to 2019 seven partial nephrectomies with removal of the tumor thrombus from the main renal vein were performed. Absolute imperative indications were recorded in 6 (85.7%) patients (4 with solitary kidney, 2 with bilateral tumors). Dimensions of renal tumor averaged 6.5±2.3 cm. Intravenous part of the tumor penetrated the initial portion of the renal vein in 3 cases, main trunk of the renal vein in 3 cases, and cavarenal portion of the IVC in 1 case. The average length of the tumor thrombus was 24.0±6.9 mm, and the width was 9.3±4.8 mm. Tumor thrombi were classified as intrarenal and extrarenal. In accordance with this principle surgical procedures were divided into partial nephrectomy with intrarenal (3/42.9%) and extrarenal thrombectomy (4/57.1%). Intrarenal thrombectomy was characterized by thrombus removal out of the vein lumen from the side of the kidney resection area, while extrarenal thrombectomy included additional opening the lumen of the main renal vein or inferior vena cava (IVC). In one patient hypothermic perfusion of the kidney in situ was used. In two cases the extracorporeal partial nephrectomy with kidney autotransplantation was performed. Warm ischemia time averaged 14.0 minutes. The time of ischemia during hypothermic perfusion in situ reached 76 minutes, the time of cold ischemia during extracorporeal surgery averaged 68.0 minutes. The volume of blood loss did not exceed an average of 621.4±146.8 ml. Early postoperative complications occurred in 4 (57.1%) cases (bleeding -1, ischemic stroke -1, deterioration of renal failure -2). Postoperative mortality was registered in 1 patient due to bleeding and heart failure. The follow-up period averaged 28.7±18.9 months. Distant metastases occurred in 1 (14.3%) patient after 16 months. Local tumor recurrence in the remnant kidney after nephron-sparing surgery was not detected in any case. Nephron-sparing surgery may be used to treat patients with kidney tumors and neoplastic venous thrombosis. However, this complex surgical approach requires further technical improvement.

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Recent conservation planning studies have presented approaches for integrating spatially referenced social (SRS) data with a view to improving the feasibility of conservation action. We reviewed the growing conservation literature on SRS data, focusing on elicited or stated preferences derived through social survey methods such as choice experiments and public participation geographic information systems. Elicited SRS data includes the spatial distribution of willingness to sell, willingness to pay, willingness to act, and assessments of social and cultural values. We developed a typology for assessing elicited SRS data uncertainty which describes how social survey uncertainty propagates when projected spatially and the importance of accounting for spatial uncertainty such as scale effects and data quality. These uncertainties will propagate when elicited SRS data is integrated with biophysical data for conservation planning and may have important consequences for assessing the feasibility of conservation actions. To explore this issue further, we conducted a systematic review of the elicited SRS data literature. We found that social survey uncertainty was commonly tested for, but that these uncertainties were ignored when projected spatially. Based on these results we developed a framework which will help researchers and practitioners estimate social survey uncertainty and use these quantitative estimates to systematically address uncertainty within an analysis. This is important when using SRS data in conservation applications because decisions need to be made irrespective of data quality and well characterized uncertainty can be incorporated into decision theoretic approaches.

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Detonation carbon materials (DCM) composed of non-equilibrium nano-structures show the low-threshold field emission (LTFE). These materials have forward-looking application especially due to high reproducibility of the LTFE-phenomenon on a surface of emitter, where the emitting centers are homogeneously distributed. In this paper we link the effect of LTFE to the nature of the corresponding wave functions based on the experiment results obtained for DCM by the field effect on electrolytes. As we had shown before DCM had been described by an ultra-relativistic dispersion function with extremely small effective mass of electrons and the size-quantization effect had been observed in DCM at even room temperature. Our results based on emission and electrolyte technics of the field-effect measurements in DCM along with modern observations of the field emission in strong electric fields allowed to propose a new resonance transmission model for LTFE-phenomenon, which is alternative to most widely discussed models based on the field-enhancing factors or barrier-lowering mechanisms.

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Interleukin-2 (IL-2) remains the mainstay of treatment for metastatic renal cell carcinoma (RCC), but minimally invasive surgical techniques have provided new options for the combined treatment of RCC. Two patients with metastatic RCC to the head and neck treated by combined laser-induced thermal therapy and IL-2 were described in this case report. Both patients had an extended survival compared to the historical survival of 10 months for metastatic RCC but eventually succumbed to progressive disease. The authors' initial experience with metastatic RCC suggests that laser thermoablation and immunotherapy in selected patients with metastatic RCC is warranted as a palliative treatment, but a larger study with long-term follow-up is necessary to determine the effectiveness of this approach.

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Nonmuscle myosin II plays fundamental roles in cell body translocation during migration and is typically depleted or absent from actin-based cell protrusions such as lamellipodia, but the mechanisms preventing myosin II assembly in such structures have not been identified [1-3]. In Dictyostelium discoideum, myosin II filament assembly is controlled primarily through myosin heavy chain (MHC) phosphorylation. The phosphorylation of sites in the myosin tail domain by myosin heavy chain kinase A (MHCK A) drives the disassembly of myosin II filaments in vitro and in vivo [4]. To better understand the cellular regulation of MHCK A activity, and thus the regulation of myosin II filament assembly, we studied the in vivo localization of native and green fluorescent protein (GFP)-tagged MHCK A. MHCK A redistributes from the cytosol to the cell cortex in response to stimulation of Dictyostelium cells with chemoattractant in an F-actin-dependent manner. During chemotaxis, random migration, and phagocytic/endocytic events, MHCK A is recruited preferentially to actin-rich leading-edge extensions. Given the ability of MHCK A to disassemble myosin II filaments, this localization may represent a fundamental mechanism for disassembling myosin II filaments and preventing localized filament assembly at sites of actin-based protrusion.

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We have constructed expression vectors for Dictyostelium discoideum which encode a green fluorescent protein (GFP) sequence upstream of a multicloning site for introduction of sequences of interest. Insertion of cDNAs into the multicloning site results in expression of fusion protein bearing an amino- or carboxyl-terminal GFP tag which can be used for fluorescent localization studies in Dictyostelium cells. A parallel construct fuses a FLAG epitope tag at the amino terminus of expressed protein. Each fusion cartridge was placed either in a G418-resistance vector allowing transactivated Ddp2-based extrachromosomal replication or in a vector allowing autonomous Ddp1-based replication. Distinct differences in expression stability were observed in the two vector types. When GFP-expressing cells were analyzed by fluorescence microscopy, significant cell-to-cell variability in expression level was observed when expression was based on the Ddp2 vector, while less cell-to-cell variation in expression level was observed when the Ddp1 backbone was used for expression.

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A novel method for subtotal gastric resection is described with the construction of an isoantiperistaltic artificial stomach formed from the small intestine and the duodenum at Treitz's ligament without any intestinal inserts, Brown's and Roux's anastomoses, and with an invaginated anastomosis between the stomach and the reservoir measuring 1.5-2 cm in length. Fifty-nine operations were performed. No incoherent sutures were observed in the gastric-reservoir anastomosis. In 1 patient, due to a technical fault, duodenal necrosis with fatal outcome was encountered. Two patients developed pancreatic necrosis of the horizontal part of the duodenum. The general condition of all of the followed-up patients is good. They had a weight gain ranging from 2 to 15 kg. When a broad anastomosis (exceeding 3 cm) was constructed, in 6 patients examined by endoscopy done in a horizontal position, small volumes of bile reflux into the gastric stub were found. In gastric resections performed according to Billroth II, a refluent gastritis was observed in 62.3% of the patients.

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