Rastezljivost i električna svojstva legura Al–Si u ovisnosti o torziji i napetosti

The relation between tensile strain ∆L/L0 and the relative change in resistance ∆R/R0 caused by torsion-tension deformation for Al-Si samples pre-annealed at different temperatures (room temperature up to 773 K) was studied. The empirical relation ∆L/L0 = k∆R/R0 was found, where k is a constant depending on the silicon content and its distribution in the matrix.Razmotren je odnos rastezljivosti ∆L/L0 i relativne promjene električne otpornosti ∆R/R0 koja nastaje zbog torzije i napetosti u uzorcima Al–Si prethodno otpuštanim na različitim temperaturama (293 do 773 K). Postavljen je empirički izraz ∆L/L0 = k∆R/R0, gdje konstanta k ovisi o količini i raspodjeli silicija u matrici legure

Preparation and Characterization of Vanadium Pentoxide Using Spray Pyrolysis Technique

A chemical spray pyrolysis technique was used to deposit a vanadium pentoxide (V2O5) thin films on glass substrate with a deposition temperature ranged from 300°C to 500°C in step of 50°C. From ammonium meta vanadate aqua precursor solution molarity of (0.1 M) was used as a source of vanadium. The effect of deposition temperature on structure, morphological, electrical conductivity and optical properties wasanalyzedat constant preparation time, solution molarity and the distance between spray nozzle and substrate.X-ray diffraction patterns shown that an orthorhombic cubic structure withgrowth along (001) plane. With increasing the substrate temperature, the electrical conductivity was increased, and the scanning electron microscopy clarified that the crystallinity of V2O5 thin films was effectively modified. The optical results revealed that energy band gap of V2O5 films deposited at 400oC, 450oC and 500oC is 2.38 eV for direct allowed transition. Based on the observed results the V2O5 phase can be well controlled by altering the substrate temperature. All prepared thin films up to 400oC show transparency in both visible and near IR region

Methods of determination of oxygen to uranium ratios in uranium dioxide

Methods used for the determination of oxygen to uranium ratios has been collected and discussed. These methods are destructive and non destructive. The experimental procedures are written in form of manuals to help their easy use in nuclear fuel quality control laboratories. It is of special importance in nuclear fuel laboratories of the nuclear metallurgy department of ARE-AEA in connection with the R&D fuel programme conceived within the scope or German - Egyptian cooperation between the Jülich Nuclear Research Centre and the Nuclear Research Centre at Inchas, AEA - Egypt. The accuracy and place of use of each method has been tabulated

Does the revised cardiac risk index predict cardiac complications following elective lung resection?

Background: Revised Cardiac Risk Index (RCRI) score and Thoracic Revised Cardiac Risk Index (ThRCRI) score were developed to predict the risks of postoperative major cardiac complications in generic surgical population and thoracic surgery respectively. This study aims to determine the accuracy of these scores in predicting the risk of developing cardiac complications including atrial arrhythmias after lung resection surgery in adults. Methods: We studied 703 patients undergoing lung resection surgery in a tertiary thoracic surgery centre. Observed outcome measures of postoperative cardiac morbidity and mortality were compared against those predicted by risk. Results: Postoperative major cardiac complications and supraventricular arrhythmias occurred in 4.8% of patients. Both index scores had poor discriminative ability for predicting postoperative cardiac complications with an area under receiver operating characteristic (ROC) curve of 0.59 (95% CI 0.51-0.67) for the RCRI score and 0.57 (95% CI 0.49-0.66) for the ThRCRI score. Conclusions: In our cohort, RCRI and ThRCRI scores failed to accurately predict the risk of cardiac complications in patients undergoing elective resection of lung cancer. The British Thoracic Society (BTS) recommendation to seek a cardiology referral for all asymptomatic pre-operative lung resection patients with > 3 RCRI risk factors is thus unlikely to be of clinical benefit

Video-assisted thoracoscopic lobectomy: which patients require postoperative physiotherapy?

Objectives: Following major thoracic surgery physiotherapy is recommended to improve reduced lung volume, aid secretion clearance, and improve mobility, however, in many centres physiotherapy provision is variable following minimally invasive video-assisted thoracoscopic surgery (VATS). The objective of this study was to observe frequency of problems potentially amenable to physiotherapy following VATS lobectomy, and to identify associated baseline factors of patients in whom physiotherapy may be beneficial. Methods: A prospective observational study was performed including all consecutive cancer patients undergoing VATS lobectomy in a regional centre over 4 years (2012–2016). Standard postoperative care included early mobilisation by nursing staff from postoperative day one (POD1). Physiotherapy assessment of all patients on POD1 determined presence of issues potentially amenable to physiotherapy intervention, and treatment was commenced. Outcome measures included postoperative pulmonary complication (PPC) development, hospital and high dependency unit (HDU) length of stay (LOS). Results: Of 285 patients, 209 (73%) received physiotherapy to assist/improve reduced mobility, of these 23 (8%) also received sputum clearance therapies and 65 (23%) specific therapy for lung volume loss. The remaining 76 (27%) patients had significantly lower hospital/HDU LOS (P < 0.001) reflecting uncomplicated recovery. Chronic obstructive pulmonary disease (COPD), body mass index (BMI), preoperative mobility and age were independently associated with issues potentially amenable to physiotherapy (P = 0.013). Conclusion: Following VATS lobectomy a large proportion of patients demonstrated issues potentially amenable to physiotherapy. The authors recommend that patients receive routine physiotherapy assessment following this type of surgery to ensure that all issues are identified early. Screening of COPD, BMI, preoperative mobility and age will allow early identification of patients who may benefit most from postoperative physiotherapy and preoperative optimisation, however, these factors cannot predict the need for physiotherapy

Evolution of Fermi surface and normal-state gap in chemically substituted cuprates Bi2_{2}Sr2−x_{2-x}Bix_{x}CuO6+δ_{6+\delta}

We have performed a systematic angle-resolved photoemission study of chemically substituted cuprates Bi$_{2}$Sr$_{2-x}$Bi$_{x}$CuO$_{6+\delta}$. We observed that the Fermi surface area shrinks linearly with Bi substitution content $x$, reflecting the electron doping nature of this chemical substitution. In addition, the spectral linewidth broadens rapidly with increasing $x$, and becomes completely incoherent at the superconducting-insulating boundary. The d-wave-like normal-state gap observed in the lightly underdoped region gradually evolves into a large soft gap, which suppresses antinodal spectral weight linearly in both the excitation energy and temperature. Combining with the bulk resistivity data obtained on the same samples, we establish the emergence of the Coulomb gap behavior in the very underdoped regime. Our results reveal the dual roles, doping and disorder, of off-plane chemical substitutions in high-$T_c$ cuprates and elucidate the nature of the quantum electronic states due to strong correlation and disorder.Comment: 4 pages, 4 figure

Additive Antinociceptive Effects of a Combination of Vitamin C and Vitamin E after Peripheral Nerve Injury

Accumulating evidence indicates that increased generation of reactive oxygen species (ROS) contributes to the development of exaggerated pain hypersensitivity during persistent pain. In the present study, we investigated the antinociceptive efficacy of the antioxidants vitamin C and vitamin E in mouse models of inflammatory and neuropathic pain. We show that systemic administration of a combination of vitamins C and E inhibited the early behavioral responses to formalin injection and the neuropathic pain behavior after peripheral nerve injury, but not the inflammatory pain behavior induced by Complete Freund's Adjuvant. In contrast, vitamin C or vitamin E given alone failed to affect the nociceptive behavior in all tested models. The attenuated neuropathic pain behavior induced by the vitamin C and E combination was paralleled by a reduced p38 phosphorylation in the spinal cord and in dorsal root ganglia, and was also observed after intrathecal injection of the vitamins. Moreover, the vitamin C and E combination ameliorated the allodynia induced by an intrathecally delivered ROS donor. Our results suggest that administration of vitamins C and E in combination may exert synergistic antinociceptive effects, and further indicate that ROS essentially contribute to nociceptive processing in special pain states

UK pneumonectomy outcome study (UKPOS): a prospective observational study of pneumonectomy outcome

<p>Abstract</p> <p>Background</p> <p>In order to assess the short term risks of pneumonectomy for lung cancer in contemporary practice a one year prospective observational study of pneumonectomy outcome was made. Current UK practice for pneumonectomy was observed to note patient and treatment factors associated with major complications.</p> <p>Methods</p> <p>A multicentre, prospective, observational cohort study was performed. All 35 UK thoracic surgical centres were invited to submit data to the study. All adult patients undergoing pneumonectomy for lung cancer between 1 January and 31 December 2005 were included. Patients undergoing pleuropneumonectomy, extended pneumonectomy, completion pneumonectomy following previous lobectomy and pneumonectomy for benign disease, were excluded from the study.</p> <p>The main outcome measure was suffering a major complication. Major complications were defined as: death within 30 days of surgery; treated cardiac arrhythmia or hypotension; unplanned intensive care admission; further surgery or inotrope usage.</p> <p>Results</p> <p>312 pneumonectomies from 28 participating centres were entered. The major complication incidence was: 30-day mortality 5.4%; treated cardiac arrhythmia 19.9%; unplanned intensive care unit admission 9.3%; further surgery 4.8%; inotrope usage 3.5%. Age, American Society of Anesthesiologists physical status ≥ P3, pre-operative diffusing capacity for carbon monoxide (DLCO) and epidural analgesia were collectively the strongest risk factors for major complications. Major complications prolonged median hospital stay by 2 days.</p> <p>Conclusion</p> <p>The 30 day mortality rate was less than 8%, in agreement with the British Thoracic Society guidelines. Pneumonectomy was associated with a high rate of major complications. Age, ASA physical status, DLCO and epidural analgesia appeared collectively most associated with major complications.</p