Extended X-ray absorption fine structure of dynamically-compressed copper up to 1 terapascal.

Large laser facilities have recently enabled material characterization at the pressures of Earth and Super-Earth cores. However, the temperature of the compressed materials has been largely unknown, or solely relied on models and simulations, due to lack of diagnostics under these challenging conditions. Here, we report on temperature, density, pressure, and local structure of copper determined from extended x-ray absorption fine structure and velocimetry up to 1 Terapascal. These results nearly double the highest pressure at which extended x-ray absorption fine structure has been reported in any material. In this work, the copper temperature is unexpectedly found to be much higher than predicted when adjacent to diamond layer(s), demonstrating the important influence of the sample environment on the thermal state of materials; this effect may introduce additional temperature uncertainties in some previous experiments using diamond and provides new guidance for future experimental design.

Energetics of polymeric carbon monoxide.

The transformation of carbon monoxide (CO) from a molecular liquid to a polymeric solid under isothermal compression at room temperature is investigated using first principles theory. We report structural and thermodynamic properties from ambient density up to 2.45 g/cc obtained using density functional theory molecular dynamics simulations, including hybrid exchange corrections. The theoretical results are compared with newly obtained polymeric CO samples, synthesized in a large volume press. The explosive performance of polymeric CO is predicted and discussed. Under most favorable assumptions, it is found to be comparable to trinitrotoluene.

Doppler-guided transanal hemorrhoidal dearterilization versus conventional hemorrhoidectomy for treatment of hemorrhoids - early and long-term postoperative results.

BACKGROUND: A variety of effective methods for treatment of hemorrhoids has been proposed. In recent years, there has been an increasing number of studies comparing transanal hemorrhoidal dearterilization (THD) and conventional hemorrhoidectomy (CH), but the focus of most studies has been about the early postoperative results. The data about long-term outcomes is still limited. We aimed to compare Doppler-guided THD and CH with regard to early and long-term postoperative results. METHODS: The conducted prospective research included 287 patients who underwent CH (167 cases) or Doppler-guided THD with mycopexy (120 patients) between November 2010 and December 2015. Information on hemorrhoidal stage, demographic data, presenting symptoms, complications, duration of hospital stay, postoperative pain, patients' satisfaction and follow-up were obtained. Statistical tests were performed by SPSS 19.0. RESULTS: There was no significant difference between the studied groups according to gender, mean age, preoperative prolapse, pain and pruritus, hemorrhoidal stage and postoperative complications. Preoperative bleeding was more frequent in THD group (p = 0,002). The mean visual analog scale (VAS) pain scores in CH and THD groups on days 1, 2 and 7 were 7.01 vs 5.03, 5.07 vs 2.98, 2.39 vs 0,57 (p = 0,000). Practically, there was no difference in VAS on day 30 and patients' satisfaction at the 18th month. Mean hospital stay was 5,13 (CH) and 3,38 days (THD), p = 0,000. The postoperative follow-up was between 18 and 78 months (mean 46 ± 16 months). During this stage, 5 patients (2,99%) in CH group required surgery for recurrence. In THD group, 3 patients (2,5%), all with 4th-degree hemorrhoids underwent additional procedures (p 0,802). CONCLUSIONS: Doppler-guided THD seems to be an efficient and safe option for treatment of hemorrhoids, related to lower postoperative pain and excellent, similar long-term outcomes compared to CH. For advanced grades of hemorrhoids, Doppler-guided THD could be a valuable alternative, but there is a need for patients' selection. TRIAL REGISTRATION: (retrospectively registered) researchregistry 3090 .

Liver hemangiomas--surgical point of view.

UNLABELLED: Most of the liver hemangiomas do not change substantially their size for years. In some of the cases they grow, which may correlate to complaints and a risk of complications. Due to the rarity and the benign nature of the pathology, the surgical tactics and the technical methods have not been fully clarified. The goal of the present study is to present the experience of the Department of General and Liver-pancreatic Surgery in the surgical treatment of liver hemangiomas against data of the specialized literature. MATERIALS AND METHODS: In the January 1995-March 2013 period, 101 patients were subjected to liver hemangioma surgery at the Department of General and Liver-pancreatic Surgery, UH "Alexandrovska" Sofia. Main demographic, clinical, diagnostic and surgical procedures have been analyzed. RESULTS: Of 101 operated patients, 27 (26.7%) were male and 74 (73.3%)--female, aged 25- 77, mean age--50.7. The focal lesion was successfully diagnosed with diagnostic imaging methods: 96.9% with US, 98.3% with CT and 100 % with MRI. We established diagnostic specificity of 60.3%, 55.0% and 85.7%, respectively. The following interventions were performed: 14 large liver resections of three and more segments, 35 left-side lobectomies, 35 enucleations and enucleoresections and 30 mono- and bisegmentectomies. Post-operative complications were observed with 6 (5.9%) patients. None of the patients died. CONCLUSION: The combination of modern non-invasive imaging methods reaches diagnostic sensitivity and specificity sufficient to identify the liver hemangioma and take a decision on the therapeutic conduct. The possibilities for surgical treatment is limited and is applied upon strict indications. Liver resections in different volume and enucleations should be applied after correct selection of patients, so as to ensure minimum risk of morbidity and mortality.

Clinical case of neuroendocrine malignant tumor with unusual localization in the adrenal cortex.

The authors present unusual clinical case with atypical diagnostic work-up and histological result of adrenal neuroendocrine carcinoma.

Lattice dynamics of dense lithium.

We report low-frequency high-resolution Raman spectroscopy and ab-initio calculations on dense lithium from 40 to 200 GPa at low temperatures. Our experimental results reveal rich first-order Raman activity in the metallic and semiconducting phases of lithium. The computed Raman frequencies are in excellent agreement with the measurements. Free energy calculations provide a quantitative description and physical explanation of the experimental phase diagram only when vibrational effect are correctly treated. The study underlines the importance of zero-point energy in determining the phase stability of compressed lithium.

Structural and optical properties of liquid CO2 for pressures up to 1 TPa.

We report on the use of first-principles molecular dynamics calculations to examine properties of liquid carbon dioxide in the pressure-temperature range of 0-1 TPa and 200-100 000 K. The computed equations of state points are used to predict a series of shock Hugoniots with initial starting conditions that are relevant to existing and ongoing shock-wave experiments. A comparison with published measurements up to 70 GPa shows excellent agreement. We find that the liquid undergoes a gradual phase transition along the Hugoniot and have characterized this transition based on changes in bonding and structural properties as well as the conductivity and reflectivity of the fluid.

High-pressure phases of calcium: density-functional theory and diffusion quantum Monte Carlo approach.

The phase diagram of Ca is examined using a combination of density-functional theory (DFT) and diffusion quantum Monte Carlo (DMC) calculations. Gibbs free energies of several competing structures are computed at pressures near 50 GPa. Existing disagreements for the stability of Ca both at low and room temperature are resolved with input from DMC. Furthermore, DMC calculations are performed on 0 K crystalline structures up to 150 GPa and it is demonstrated that the widely used generalized gradient approximation of DFT is insufficient to accurately account for the relative stability of the high-pressure phases of Ca. The results indicate that the theoretical phase diagram of Ca needs a revision.

[Sepsis--current aspects].

Sepsis is defined as a clinical syndrome of systemic response to infections. With progression of the disease develop organ failure (i.e. severe sepsis) and hypotension (i.e. septic shock) and mortality increases significantly. Sepsis is an interdisciplinary problem, cause significant morbidity and mortality and higher hospital costs. Deepening ofinflammation, immunity distortions, coagulation and oxygen perfusion have a major role in organ dysfunction and death. Proper diagnosis of sepsis requires an understanding of risk factors, a high index of suspicion and anatomic approach to the localization of the infectious focus. Early detection of septic patients is crucial for the outcome of disease in the application of reasoned therapy. Future treatment of sepsis associated with a better understanding of the molecular bases of pathological process.

[Contemporary surgical treatment for unresectable periampullary tumors. Double or tripple by-pass surgery].

BACKGROUND/AIM: Pancreatic neoplasms continues to be a highly lethal disease with poor prognosis. This single-institution experience reviews the palliative surgical techniques used in a group of patients with periampullary tumors accenting to a technique of pancreato-wirsungo-jejunostomy, protesed with "perdue"-drain and combined with gastroenterostomy. MATERIALS AND METHODS: For the period of 01.01.2006-31.12.2007 in the Clinic of General and Liver-Pancreatic Surgery of University Hospital "Alexandrovska" are operated 162 patients with pancreatic cancer. 113 of them are with periampullary localization of the tumor, 49 are with localization at the body or at the tail of pancreatic gland. In 97 of the cases a different palliative procedures was performed. In two cases the technique of pancreato-wirsungo-jejunostomy, protesed with "perdue"-drain and combined with gastroenterostomy was performed. RESULTS: The levels of the postoperative mortality and morbidity in patients with palliative surgical procedures are 6.2%, respectively 39.2%. The level of early pastoperative morbidity and mortality in cases with pancreato-wirsungo-jejunostomy, protesed with "perdue"-drain and combined with gastroenterostomy is 0%. CONCLUSION: For patients with advanced periampullary malignacies, the prevention and alleviation of suffering due to obstructive jaundice, gastric outlet obstruction, cancer-related pain and pancreatic exocrine insufficiency is of primary importance. We think that the operative technique is represented by us useful often at patients with chronic pancreatitits, but the tehnique will be useful in given conditions for patients with unresectable periampullar pancreatic neoplasms.

[Improved technique for internal biliary-digestive drainage during conventional palliative procedure of nonresectable tumors of periampullary region].

AIM: We represent variation of bilio-digestive stomy with "lost" protecting drainage during conventional palliative procedure of nonresectable tumors of periampullary region. MATERIALS AND METHODS: During the period 01.01.2008 -31.05.2008 in the Clinic of general and liver-pancreatic surgery-"Aleksandrovska" Hospital, Sofia, we applied modified technique for internal bilio-digestive prosthetic drain with "lost" drainage, protecting choledocho-duodenostomy in 12 patients with nonresectable tumors of periampullary region. Eight of them are males and 4--females, with age between 60-82 (average 64,5). In 8 patients we found nonresectable malignancy of the head of pancreas and in 4 nonresectable malignancy of distal part of the common bile duct. RESULTS: We follow the early postoperative results and postoperative period during tree months. We did not have insufficiency of the choledocho-duodenostomy and that afford early discharge of the patients. At the end of third month we haven't observed jaundice or other complications cause of obstruction of protecting drainage. CONCLUSION: We consider that the technique is useful and appropriate when doing choledocho-duodenostomy cause of nonresectable periampullary neoplasms. The using of this technique don't increase the postoperative morbidity and improve early postoperative results.

[Large primary liver cancer (> 10 cm)- diagnosis and surgical treatment].

BACKGROUND: Primary liver cancer (PLC) over 10 cm. in diameter at the time of diagnosis continues to account for a number of patients undergoing hepatic resection. This study evaluated the clinicopathological features and outcome following surgery for large PLC. METHODS: Between January 1991 and December 2002 , 105 patients were operated, 68 of them (64.7%) the size of tumor was > 10 cm. Forty-five patients (66.2%) with a large PLC(greater than 10 cm) were resected and studied retrospectively. They were compared with 27 patients who had tumor less than 10 cm. They were 31 men and 14 women of mean age 53,8 (from 1 to 78 years). Cirrhosis had 13 patients (28,9%) - Child A- 10, Child B - 3. RESULTS: Surgical procedures were: major resections in 33 patients and minor resections in 12. Eight patients (17,7%) died by the 30-th day. 16 patients had postoperative complications - 6 patients developed liver failure. The 1-, 2-, 3- and 5-year overall survival rates were 68%, 43%, 22% , 2,2% respectively. CONCLUSION: Large primary liver cancer can be safely resected when cirrhosis is absent. Liver cirrhosis is contraindication for major hepatic resection. The lack of cirrhosis increases resectability and decreases morbidity and mortality.

[Cystopericystectomy for the treatment of hepatic hydatid disease].

UNLABELLED: Hepatic hydatid disease is current problem in Bulgaria as the country in endemic region. The treatment include PAIR, various type surgical procedures and medical therapy. Surgical treatment is conductive. Cystopericystectomy is one of radical procedures. AIM: The aim of this study is to present the experience of Department of General and Liver-Pancreatic Surgery in Uiversity Hospital "Alexandrovska", Sofia with cystopericystectomy. MATERIAL AND METHODS: During the period of 18-years (1988-2005) done 90 cystopericystectomies on the 79 patients--57 (72.15%) female and 22 (27.85%) male. Diagnosis has become easier with advances in ultrasonic imaging, immunological tests and CT scanning. The cysts ware localised in left lobe--56 (62.2%) and right lobe--34 (37.8%). RESULTS: There was complication in 4 (5.0%) of patients. Median postoperative stay is 10.3 days. There wasn't reoperacions and lethal outcome. CONCLUSION: Cystopericystectomy is difficult operative procedure, but it followed with better results. It's necessary strictly abidance of the evidences.

New method for evaluation of in vivo scattering and refractive index properties obtained with optical coherence tomography.

Optical coherence tomography (OCT) provides more parameters than pure morphology does. In a recent paper [A. Knuettel and M. Boehlau-Godau, J. Biomed. Opt. 5(1) 83-92 (2000)] we have shown that the refractive index (RI) can be evaluated in a localized manner in skin tissue under in vivo conditions. Based on a theory, originally developed for light detecting and ranging applications [L. Thrane et al., J. Opt. Soc. Am. A 17(3) 484-490 (2000)], the parameter mean scattering angle (MSA) could be derived in addition to RI. The effects of hydration on MSA and RI have been evaluated in vitro in pigskin and in vivo in human skin with our OCT scanner SkinDex 300. These parameters may have a viable impact in (cosmetic) skin research and clinical diagnoses. To the best of our knowledge, this is the first time that (multiple) scattering of light has been quantified through the observation of a new scattering parameter under in vivo conditions.

High-pressure molecular phases of solid carbon dioxide.

We present a theoretical study of solid CO2 up to 50 GPa and 1500 K using first-principles calculations. In this pressure-temperature range, interpretations of recent experiments have suggested the existence of CO2 phases which are intermediate between molecular and covalent-bonded solids. We reexamine the concept of intermediate phases in the CO2 phase diagram and propose instead molecular structures, which provide an excellent agreement with measurements.

Enhanced Friedel structure and proton pairing in dense solid hydrogen.

The mechanism of proton pairing in dense solid hydrogen, and its progression with density, are both studied using effective potentials between protons which include electronic response up to quadratic terms. For high pressures nonlinear effects originating with different pairs are crucial in establishing the net attraction within a given pair, and in this picture Friedel oscillations are considerably enhanced by quadratic response, subsequently playing a very important role in the overall pairing. Calculated vibron frequencies also show substantial agreement with experiment, reflecting at the same time significant changes in the physical character of the pairing itself.

[A variant of hepatico-jejunostomy in Klatskin tumors]. / Variant na khepatiko (khepatitse-) ieiunostomiia pri Tu Klatskin.

The authors present their own variant of performing anastomoses between the common hepatic duct/right and left hepatic ducts and the jejunum in radical treatment of Klatskin tumors. The procedure is indicated in cases of proximal (hilar) resection of both hepatic ducts, in technical difficulties for performing the standard drainage protected end-to-side anastomosis between the right and left hepatic ducts on the one hand and the jejunum on the other as well as a method for double biliary derivation. The advantages of the procedure include decreased incidence rate of bile leakage in the subhepatic region, low risk of diffuse biliary peritonitis respectively and restricted possibility of intestinal reflux into the biliary tract.