Dynamics of Uniform Quantum Gases, II: Magnetic Susceptibility

A general expression for temperature-dependent magnetic susceptibility of quantum gases composed of particles possessing both charge and spin degrees of freedom has been obtained within the framework of the generalized random-phase approximation. The conditions for the existence of dia-, para-, and ferro-magnetism have been analyzed in terms of a parameter involving single-particle charge and spin. The zero-temperature limit retrieves the expressions for the Landau and the Pauli susceptibilities for an electron gas. It is found for a Bose gas that on decreasing the temperature, it passes either through a diamagnetic incomplete Meissner-effect regime or through a paramagnetic-ferromagnetic large magnetization fluctuation regime before going to the Meissner phase at BEC critical temperature

Possible potentials responsible for stable circular relativistic orbits

Bertrand's theorem in classical mechanics of the central force fields attracts us because of its predictive power. It categorically proves that there can only be two types of forces which can produce stable, circular orbits. In the present article an attempt has been made to generalize Bertrand's theorem to the central force problem of relativistic systems. The stability criterion for potentials which can produce stable, circular orbits in the relativistic central force problem has been deduced and a general solution of it is presented in the article. It is seen that the inverse square law passes the relativistic test but the kind of force required for simple harmonic motion does not. Special relativistic effects do not allow stable, circular orbits in presence of a force which is proportional to the negative of the displacement of the particle from the potential center.Comment: 11 pages, Latex fil

Time-and-motion tool for the assessment of working time in tuberculosis laboratories: a multicentre study

SETTING: Implementation of novel diagnostic assays in tuberculosis (TB) laboratory diagnosis requires effective management of time and resources. OBJECTIVE: To further develop and assess at multiple centres a time-and-motion (T&M) tool as an objective means for recording the actual time spent on running laboratory assays. DESIGN: Multicentre prospective study conducted in six European Union (EU) reference TB laboratories. RESULTS: A total of 1060 specimens were tested using four laboratory assays. The number of specimens per batch varied from one to 60; a total of 64 recordings were performed. Theoretical hands-on times per specimen (TTPS) in h:min:s for Xpert® MTB/RIF, mycobacterial interspersed repetitive unit-variable number of tandem repeats genotyping, Ziehl-Neelsen staining and manual fluorescence microscopy were respectively 00:33:02 ± 00:12:32, 00:13:34 ± 00:03:11, 00:09:54 ± 00:00:53 and 00:06:23 ± 00:01:36. Variations between laboratories were predominantly linked to the time spent on reporting and administrative procedures. Processing specimens in batches could help save time in highly automated assays (e.g., line-probe) (TTPS 00:14:00 vs. 00:09:45 for batches comprising 7 and 31 specimens, respectively). CONCLUSIONS: The T&M tool can be considered a universal and objective methodology contributing to workload assessment in TB diagnostic laboratories. Comparison of workload between laboratories could help laboratory managers justify their resource and personnel needs for the implementation of novel, time-saving, cost-effective technologies, as well as identify areas for improvement

Correlations Between Oxidative Stress Markers and Coronary Anatomy in Percutaneously Treated Patients With Acute ST-elevation Myocardial Infarction

Understanding biochemical mechanisms involved in acute myocardial infarction is crucial for future treatments. The current study analyzed the oxidative stress markers in patients with percutaneously treated acute ST-elevation myocardial infarction and correlated the findings to coronary anatomy and Syntax II score (SS-II). Blood samples were obtained before coronary re-perfusion, after one and 24 hours. The following markers of oxidative stress were determined: malondialdehyde (MDA), reduced glutathione to oxidized glutathione ratio (GSH/GSSG) and total antioxidant capacity (TAC). Thirty-seven consecutive patients were included. The patients were divided into groups according to the infarct-related artery: left anterior descending artery (LAD- group) vs non-LAD group, and according to the calculated SS-II, SS-II≤ 34 vs. SS-II>34. MDA concentration and GSH/GSSG ratio showed non-significant differences between LAD vs non-LAD groups at all time frames. Patients with LAD as the infarct-related artery had a significantly lower TAC 24 hours after re-perfusion: 30.22 ± 9.78 % inhibition in the LAD group vs. 35.7 ± 5.78 % inhibition in the non-LAD group, p=0.013. The oxidative stress markers were similar between patients regardless of the SS-II value, and neither the culprit vessel nor the SS-II significantly influenced the dynamics of oxidative stress markers

The Role of Ultrasound in Accessing the Distal Radial Artery at the Anatomical Snuffbox for Cardiovascular Interventions

In an effort to refine transcatheter vascular interventions, radial artery access has moved more distally at the anatomical snuffbox. Here, more challenges appear as the artery is smaller, more angulated, and more difficult to palpate. Including ultrasound guidance as a mandatory step during puncture may encourage more operators to switch to this approach. In the femoral approach, ultrasound guidance is strongly recommended because of bleeding complications, whereas in the proximal (conventional) radial approach, the role of ultrasound remains optional, and in current practice, almost all cases are performed by palpation of the pulse only. However, in distal radial access, the situation is different because the artery differs in caliber and position, and imaging can help the operator for a clean puncture, especially since repeated punctures are not only painful but also any hematoma formation leads to the complete compression of the artery and failure of access. The aim of this review is to investigate the rationale of vascular ultrasound during distal radial access and to establish some techniques and anatomical landmarks for the ultrasonographic exploration of the dorsal area of the hand

Approaches to Peripheral Artery Disease in Diabetes : Are There Any Differences?

Peripheral artery disease (PAD) increases the risk of diabetes, while diabetes increases the risk of PAD, and certain symptoms in each disease increase the risk of contracting the other. This review aims to shed light on this harmful interplay between the two disorders, with an emphasis on the phenotype of a patient with both diabetes and PAD, and whether treatment should be individualized in this high-risk population. In addition, current guideline recommendations for the treatment of PAD were analyzed, in an attempt to establish the differences and evidence gaps across a population suffering from these two interconnected disorders

HIGH-DOSE STATIN PRIOR TO PRIMARY PERCUTANEOUS CORONARY INTERVENTION REDUCES OXIDATIVE STRESS BURDEN IN PATIENTS WITH ACUTE ST-ELEVATION MYOCARDIAL INFARCTION

The current study analysed the effect of high-dose statin loading prior to primary percutaneous coronary intervention on oxidative stress markers, in patients with acute ST-elevation myocardial infarction (STEMI). Besides the lipid lowering effect, statins have antioxidant properties that might reduce myocardial ischemia-reperfusion injury. From a total of 37 patients, 18 patients received high-dose statin before coronarography and were included in the statin group, while 19 statin naive patients were included in the control group. Peripheral venous blood samples were obtained before coronary reperfusion, at 1 hour and 24 hours after that. The following markers of oxidative stress were determined from the serum: malondialdehyde (MDA), reduced glutathione to oxidized glutathione ratio (GSH/GSSG) and total antioxidant capacity (TAC). Values are shown as medians and interquartile ranges. MDA concentration and TAC had non-significant differences between the two groups, at all time frames. Before angioplasty, GSH/GSSG ratio was comparable between the two groups: 3.59 (2.13-5.37) in the statin group vs 2.69 (2.15-5.02) in the control group, p=0.49. At 1 hour after reperfusion, values were still similar: 2.26 (1.32-4.28) in the statin group vs 2.33 (1.88-2.50) in the control group, p=0.55. After 24 hours, there was a significant increase of GSH/GSSG ratio in the statin group 2.41 (1.58-3.28) vs 1.56 (1.12-2.03) in the control group, p=0.01. This finding suggest that, in STEMI patients, high-dose statin loading before primary percutaneous coronary intervention significantly reduces oxidative stress burden, early after administration