Brane world models need low string scale

Models with large extra dimensions offer the possibility of the Planck scale being of order the electroweak scale, thus alleviating the gauge hierarchy problem. We show that these models suffer from a breakdown of unitarity at around three quarters of the low effective Planck scale. An obvious candidate to fix the unitarity problem is string theory. We therefore argue that it is necessary for the string scale to appear below the effective Planck scale and that the first signature of such models would be string resonances. We further translate experimental bounds on the string scale into bounds on the effective Planck scale

Electrochemical reduction of carbamazepine in ethanol and water solutions using a glassy carbon electrode

The electrochemical reduction of carbamazepine in ethanol and water using a glassy carbon electrode has been studied. In all experimental conditions of scan rate and concentration of carbamazepine an irreversible cathodic wave was observed by cyclic voltammetry (CV). Electrochemical parameters and a plausible EqC mechanism have been reported from the electrochemical measurements and digital simulation. The values of thermodynamic E1/2 were correlated with solvent polarity parameters that it can be interesting for biological, pharmaceutical and forensic purposes. Limits of Detection (LOD) for DPV are 1.1 and 9.0 g/mL (4.65x10-6 and 3.81x10-5 M) in ethanol and water, respectively. The precision and recoveries obtained for tablets and plasma samples showed that the method could be successfully used for analysis

Exploring Differences Among Student Populations During Climate Graph Reading Tasks: An Eye Tracking Study

Communicating climate information is challenging due to the interdisciplinary nature of the topic along with compounding cognitive and affective learning challenges. Graphs are a common representation used by scientists to communicate evidence of climate change. However, it is important to identify how and why individuals on the continuum of expertise navigate graphical data differently as this has implications for effective communication of this information. We collected and analyzed eye-tracking metrics of geoscience graduate students and novice undergraduate students while viewing graphs displaying climate information. Our findings indicate that during fact-extraction tasks, novice undergraduates focus proportionally more attention on the question, title and axes graph elements, whereas geoscience graduate students spend proportionally more time viewing and interpreting data. This same finding was enhanced during extrapolation tasks. Undergraduate novices were also more likely to describe general trends, while graduate students identified more specific patterns. Undergraduates who performed high on the pre-test measuring graphing skill, viewed graphs more similar to graduate students than their peers who performed lower on the pre-test

Denosumab-associated osteonecrosis of the jaw; A case series and literature review

Introduction: Medication-related osteonecrosis of the jaw (MRONJ) is a severely debilitating condition of multifactorial pathogenesis. It primarily involves patients receiving intravenous bisphosphonates (BPs) and most recently the new antiresorptive drug, denosumab, for the treatment of skeletal-related malignancies. There is no curative treatment and no consensus exists regarding the clinical management of such patients. This review aims to share our current clinical experience at Sheffield Teaching Hospitals’ Trust and raise awareness of the increase in severity of ONJ in patients receiving denosumab. Patients and Methods: Four new cases with clinical diagnosis of MRONJ were presented to Sheffield Teaching Hospitals’ Trust. MRONJ was attributed to denosumab therapy, as all patients were treated solely with denosumab for skeletal-related malignancies. Results: All cases appear to have a more aggressive mode of ONJ compared to that seen with IV and/or oral BPs so far. The cause of MRONJ was observed in the presence of periodontal disease alone and following dental extractions. Progression of the disease occurred considerably faster with the development of widespread suppuration and tooth mobility within weeks. Imaging revealed rather extensive areas of bony destruction, sometimes with associated periosteal reaction in keeping with a chronic bony infection. Conclusion: It is imperative for all dental and medical teams involved in treating these patients to understand the side effects of RANKL inhibitors on bone metabolism and how it affects treatment. Helping patients to understand the chronicity and potential progression of the disease is essential to a satisfactory outcome

Lemons to Lemonade: Educational Modifications During the COVID-19 Pandemic and their Utility Moving Forward

The COVID-19 pandemic necessitated changes across social institutions, including education. This case study outlines specific innovations using five cases of pedagogical developments made by social science faculty members at a public university, and their utility for undergraduate students in a post-pandemic world. These innovations relate specifically to office hour scheduling, class assignment reminders, building informal class support groups, experiential learning, and virtual paper submission and evaluation. For each case, we outline the implementation procedure, evaluate its effectiveness, and discuss the benefits. We argue that these methods, forged during “challenging times”, will help improve students’ experiences and success during their time in college, and benefit instructors in higher education in a variety of ways

Entanglement of distant optomechanical systems

We theoretically investigate the possibility to generate non-classical states of optical and mechanical modes of optical cavities, distant from each other. A setup comprised of two identical cavities, each with one fixed and one movable mirror and coupled by an optical fiber, is studied in detail. We show that with such a setup there is potential to generate entanglement between the distant cavities, involving both optical and mechanical modes. The scheme is robust with respect to dissipation, and nonlocal correlations are found to exist in the steady state at finite temperatures.Comment: 12 pages (published with minor modifications

Computational Design of Chemical Nanosensors: Metal Doped Carbon Nanotubes

We use computational screening to systematically investigate the use of transition metal doped carbon nanotubes for chemical gas sensing. For a set of relevant target molecules (CO, NH3, H2S) and the main components of air (N2, O2, H2O), we calculate the binding energy and change in conductance upon adsorption on a metal atom occupying a vacancy of a (6,6) carbon nanotube. Based on these descriptors, we identify the most promising dopant candidates for detection of a given target molecule. From the fractional coverage of the metal sites in thermal equilibrium with air, we estimate the change in the nanotube resistance per doping site as a function of the target molecule concentration assuming charge transport in the diffusive regime. Our analysis points to Ni-doped nanotubes as candidates for CO sensors working under typical atmospheric conditions

Rotational Feshbach Resonances in Ultracold Molecular Collisions

In collisions at ultralow temperatures, molecules will possess Feshbach resonances, foreign to ultracold atoms, whose virtual excited states consist of rotations of the molecules. We estimate the mean spacing and mean widths of these resonant states, exploiting the fact the molecular collisions at low energy display chaotic motion. As examples, we consider the experimentally relevant molecules O_2, OH, and PbO. The density of s-wave resonant states for these species is quite high, implying that a large number of narrow resonant states will exist.Comment: 4 pages, 2 figure

ATP-Binding Cassette Systems of Brucella

Brucellosis is a prevalent zoonotic disease and is endemic in the Middle East, South America, and other areas of the world. In this study, complete inventories of putative functional ABC systems of five Brucella species have been compiled and compared. ABC systems of Brucella melitensis 16M, Brucella abortus 9-941, Brucella canis RM6/66, Brucella suis 1330, and Brucella ovis 63/290 were identified and aligned. High numbers of ABC systems, particularly nutrient importers, were found in all Brucella species. However, differences in the total numbers of ABC systems were identified (B. melitensis, 79; B. suis, 72; B. abortus 64; B. canis, 74; B. ovis, 59) as well as specific differences in the functional ABC systems of the Brucella species. Since B. ovis is not known to cause human brucellosis, functional ABC systems absent in the B. ovis genome may represent virulence factors in human brucellosis