Holistic Nanowire Laser Characterization as a Route to Optimal Design

Nanowire lasers are sought for near-field and on-chip photonic applications as they provide integrable, coherent, and monochromatic radiation: the functional performance (threshold and wavelength) is dependent on both the opto-electronic and crystallographic properties of each nanowire. However, scalable bottom-up manufacturing techniques often suffer from inter-nanowire variation, leading to differences in yield and performance between individual nanowires. Establishing the relationship between manufacturing controls, geometric and material properties, and the lasing performance is a crucial step toward optimisation; however, this is challenging to achieve due to the interdependance of such properties. Here, a high-throughput correlative approach is presented to characterise over 5000 individual GaAsP/GaAs multiple quantum well nanowire lasers. Fitting the spontaneous emission provides the threshold carrier density, while coherence length measurements determine the end-facet reflectivity. The performance is intrinsically related to the width of a single quantum well due to quantum confinement and bandfilling effects. Unexpectedly, there is no strong relationship between the properties of the lasing cavity and the threshold: instead the threshold is negatively correlated with the non-radiative recombination lifetime of the carriers. This approach therefore provides an optimisation strategy that is not accessible through small-scale studies

Clinical and Autoimmune Profiles of Omani Patients with True Versus False Positive Autoimmune Encephalitis Antibodies Panels

The incidence of autoimmune encephalitis (AE) is rising due to increased awareness of the condition and detection of new autoantibodies. Coinciding with this rise are false positive autoantibodies without clinical correlates. Objective: To explore the clinical profiles of Omani patients who are truly positive for AE autoantibodies and compare them with those with false-positive autoantibodies. Methods: We reviewed the medical records of all patients who tested positive for AE antibody from May 2016 to December 2022. Cases were verified by three neurologists based on the existing criteria for AE. Results: The participants comprised N = 67 patients, 19 (28%) of whom fulfilled the criteria for AE. True-positive AE patients were younger with mean age of 35.3 ± 4.7 years (p = 0.010). They were also more likely to present with subacute memory disturbances (6/19; 32%; p = 0.030), seizures (12; 63%; p = 0.028), abnormal electroencephalogram (EEG) findings (10; 65%; p = 0.040), and abnormal signals in limbic region on magnetic resonance imaging (MRI) (5; 26%; p = 0.010). Subacute memory disturbance was a significant predictor for true positivity (OR = 17.807, 95%CI = 1.608–197.202; p = 0.019). Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis was the most frequent type of AE (8; 42.1%), followed by anti-glutamic acid decarboxylase 65 (GAD65) (4; 21.1%). Conclusion: Of the 67 cases with positive AE autoantibody panel, 48 (72%) were false-positive. The presence of subacute memory impairment was a significant predictor of AE. Anti-NMDAR encephalitis was the most frequent AE encountered in our cohort

Frequency of Dimethyl Fumarate Induced Lymphopaenia Among Omani Patients with Multiple Sclerosis

Objectives: Dimethyl fumarate (DMF) is known to cause lymphopenia in treated multiple sclerosis (MS) patients. There is a dearth of research on DMF therapy in the Arab world, especially in Oman. This study aimed to analyse the prevalence of lymphopenia among Omani MS patients and the reasons for discontinuing DMF. Methods: In this retrospective study, we reviewed the medical records of Omani MS patients who were treated using DMF at two tertiary hospitals in Muscat from the period 2017 February to 2023 February. Their demographic, clinical, and laboratory data were retrieved and analysed. Absolute lymphocyte count (ALC) values at baseline and at the last follow up, as well as the reasons for discontinuing DMF were collected. Descriptive and inferential statistical techniques were used for data analysis. Binary-logistic regression analysis was used to identify the risk factors for DMF-induced lymphopenia. Results: The study included a total of 64 MS patients and the majority (40; 63%) were female. The DMF therapy was started at mean age of 33 7.7 years. After administration of DMF, 14 (21.9%) patients developed 1–3 grades lymphopenia with the following breakup: grade-1: 5/64 (7.81%) patients; grade-2: 8/64 (12.5%) patients; grade-3: 1/64 (1.6%) patient. DMF was discontinued in 23 (36.0%) patients, mainly in response to adverse events or confirmed pregnancy. Female sex was the only significant predictor of DMF-induced lymphopenia (p = 0.037). Conclusion: Most Omani MS patients had mild lymphopenia (grades 1–2), like other regional and international reports. Early adverse events and pregnancy were the main reasons provided for discontinuing DMF therapy. Keywords: Multiple Sclerosis; Dimethyl Fumarate; Absolute Lymphocyte Count; Lymphopenia; Oma

Generalized Super Efficiency Model for Ranking Efficient Decision Making Units in Data Envelopment Analysis

Abstract: In evaluating decision making units (DMU's) by using Data Envelopment Analysis (DEA) technique, we encounter the situation in which more than one unit takes efficiency score of one. In such a case, some criteria should be considered to rank the DMU's. Some efficient techniques such as AP, MAJ,etc may be used in this way. For some sets of data, with special structure in models that above mentioned, may be infeasible and unstable. In this paper, a new model is developed that all the existing drawbacks of previously applied models remove. Some numerical examples are put forward

Endophthalmitis caused by Acinetobacter spp. as the presenting manifestation of diabetes mellitus

Purpose We describe a patient with endogenous endophthalmitis caused by Acinetobacter spp. as the first clinical presentation of diabetes mellitus. Method A 48-year-old otherwise healthy woman was referred with signs and symptoms of acute endophthalmitis in the left eye. Systemic work-up, vitreous tap, and intravitreal antibiotic injection were performed followed by pars plana vitrectomy. Results The laboratory tests confirmed the diagnosis of diabetes mellitus. Vitreous culture was positive for Acinetobacter spp., and the organism was sensitive to colistin. One month after surgery, vision was no light perception, and the eye was phthisical. Conclusion Diagnostic work-up should be performed even in otherwise healthy patients with endogenous endophthalmitis. © 2016 Iranian Society of Ophthalmolog

Effect of Distributed Photovoltaic Generation on the Voltage Magnitude in a Self-Contained Power Supply System

A promising way to increase the technical and economic characteristics of standalone power supply systems is to incorporate renewable energy installations in their structure. This saves fuel and extends the operational life of diesel power stations. The most common option is a hybrid system with photovoltaic power stations incorporated into the local network of the diesel power station. This paper deals with the dependence of the deflection voltage and power losses in the electric power transmission line on the graphs of electrical loads, the parameters of elements of the power supply system, connection points and the capacity of distributed photovoltaic power stations. Research has been carried out on the common low-voltage power supply systems of the radial type (0.4 kV) with an installed capacity of up to 100 kW. The studies have been conducted by simulating the operating modes of hybrid power systems of various configurations. As a result of these studies recommendations to reduce losses and voltage variations in the network by selecting the power and photovoltaic power connection points have been put forward

Inconvenience due to travelers' diarrhea: a prospective follow-up study

<p>Abstract</p> <p>Background</p> <p>Limited data exist documenting the degree to which travelers are inconvenienced by travelers' diarrhea (TD). We performed a prospective follow-up study at the travel clinic of Leiden University Medical Center in The Netherlands to determine the degree of inconvenience and to determine how experiencing TD affects travelers' perception.</p> <p>Methods</p> <p>Healthy adults who intended to travel to the (sub)tropics for less than two months were invited to take part. Participants filled out a web-based questionnaire before departure and after returning home. TD was defined as three or more unformed stools during a 24-hour period.</p> <p>Results</p> <p>390 of 776 Eligible travelers completed both questionnaires. Participants' median age was 31 years and mean travel duration 23 days. Of 160 travelers who contracted TD (incidence proportion 41%, median duration of TD episode 2.5 days) the majority (107/160, 67%) could conduct their activity program as planned despite having diarrhea. However, 21% (33/160) were forced to alter their program and an additional 13% (20/160) were confined to their accommodation for one or more daylight days; 53 travelers (33%) used loperamide and 14 (9%) an antibiotic. Eight travelers (5%) consulted a physician for the diarrheal illness. When asked about the degree of inconvenience brought on by the diarrheal illness, 39% categorized it as minor or none at all, 34% as moderate and 27% as large or severe. In those who regarded the episode of TD a major inconvenience, severity of symptoms was greater and use of treatment and necessity to alter the activity program were more common. Travelers who contracted travelers' diarrhea considered it less of a problem in retrospect than they had thought it would be before departure.</p> <p>Conclusion</p> <p>Conventional definitions of TD encompass many mild cases of TD (in our study at least a third of all cases) for which treatment is unlikely to provide a significant health benefit. By measuring the degree of inconvenience brought on by TD, researchers and policy makers may be able to better distinguish 'significant TD' from mild TD, thus allowing for a more precise estimation of the size of the target population for vaccination or stand-by antibiotic prescription and of the benefit of such measures.</p