Genetic Algorithm-based Mapper to Support Multiple Concurrent Users on Wireless Testbeds

Communication and networking research introduces new protocols and standards with an increasing number of researchers relying on real experiments rather than simulations to evaluate the performance of their new protocols. A number of testbeds are currently available for this purpose and a growing number of users are requesting access to those testbeds. This motivates the need for better utilization of the testbeds by allowing concurrent experimentations. In this work, we introduce a novel mapping algorithm that aims to maximize wireless testbed utilization using frequency slicing of the spectrum resources. The mapper employs genetic algorithm to find the best combination of requests that can be served concurrently, after getting all possible mappings of each request via an induced sub-graph isomorphism stage. The proposed mapper is tested on grid testbeds and randomly generated topologies. The solution of our mapper is compared to the optimal one, obtained through a brute-force search, and was able to serve the same number of requests in 82.96% of testing scenarios. Furthermore, we show the effect of the careful design of testbed topology on enhancing the testbed utilization by applying our mapper on a carefully positioned 8-nodes testbed. In addition, our proposed approach for testbed slicing and requests mapping has shown an improved performance in terms of total served requests, about five folds, compared to the simple allocation policy with no slicing.Comment: IEEE Wireless Communications and Networking Conference (WCNC) 201

Effect of nitrate supplementation on skeletal muscle motor unit activity during isometric blood flow restriction exercise

Background Nitrate (NO3-) supplementation has been reported to lower motor unit (MU) firing rate (MUFR) during dynamic resistance exercise, however its impact on MU activity during isometric and ischemic exercise is unknown. Purpose To assess the effect of NO3- supplementation on knee extensor MU activities during brief isometric contractions and a 3-min sustained contraction with blood flow restriction (BFR). Methods Sixteen healthy active young adults (six females) completed two trials in a randomized, double-blind, crossover design. Trials were preceded by 5 days of either NO3- (NIT) or placebo (PLA) supplementation. Intramuscular electromyography was used to determine the m.vastus lateralis MU potential (MUP) size, MUFR and near fibre (NF) jiggle (a measure of neuromuscular stability) during brief (20 s) isometric contractions at 25% maximal strength and throughout a 3 min sustained BFR isometric contraction. Results Plasma nitrite (NO2-) concentration was elevated after NIT compared to PLA (475±93 vs.198±46 nmol·L-1, p0.05), MUP duration was shorter with NIT compared to PLA during brief isometric contractions and the sustained ischemic contraction (p<0.01). Additionally, mean MUP duration, MUP area and NF jiggle increased, and MUFR decreased over the 3 min sustained BFR isometric contraction for both conditions (all p<0.05). Conclusion These findings provide insight into the effect of NO3- supplementation on MUP properties and reveal shorter MUP duration after short-term NO3- supplementation which may have potential positive implications for skeletal muscle contractile performance

MicroRNA expression analysis in endometriotic serum treated mesenchymal stem cells

Endometriosis is defined by presence of endometrial-like-tissue outside the uterus. Recently, ectopic endometriotic lesions have been suggested to originate by abnormal differentiation of endometrial mesenchymal stem cells (eMSCs). MicroRNAs (miRNAs) play an important role in the pathophysiology of endometriosis. Through a PCR array approach, we aimed to assess the differential expression of microRNAs in human eMSC treated in culture with sera derived from women with severe endometriosis. Sera were collected from five patients with severe endometriosis and three control women and added individually in the culture medium to conduct experimental and control eMSC sets, respectively. Regular microscopic follow-up for cell morphology was performed. SYBR Green based real-time PCR array was used to assess the expression of 84 miRNAs. Bioinformatics analysis was done to predict the target genes of the significantly dysregulated miRNAs and their enriched biological processes and pathways. Thirty-two miRNAs were found significantly dysregulated in experimental cultures. Functional enrichment analysis revealed several endometriosis associated biological processes and pathways were enriched by target genes of these miRNAs. In conclusion, treatment of human eMSCs with sera of severe endometriosis cases affects the expression of certain miRNAs and their target genes. This may result in altering cell functions and consequently, endometriosis development

Two-dimensional axisymmetric formulation of high order spherical harmonics methods for radiative heat transfer

The spherical harmonics (PN) method is a radiative transfer equation solver, which approximates the radiative intensity as a truncated series of spherical harmonics. For general 3-D configurations, N(N+1)/2 intensity coefficients must be solved from a system of coupled second-order elliptic PDEs. In 2-D axisymmetric applications, the number of equations and intensity coefficients reduces to (N+1)2/4 if the geometric relations of the intensity coefficients are taken into account. This paper presents the mathematical details for the transformation and its implementation on the OpenFOAM finite volume based CFD software platform. The transformation and implementation are applicable to any arbitrary axisymmetric geometry, but the examples to test the new formulation are based on a wedge grid, which is the most common axisymmetric geometry in CFD simulations, because OpenFOAM and most other platforms do not have true axisymmetric solvers. Two example problems for the new axisymmetric PN formulation are presented, and the results are verified with that of the general 3-D PN solver, a Photon Monte Carlo solver and exact solutions

The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

Breast cancer management pathways during the COVID-19 pandemic: outcomes from the UK ‘Alert Level 4’ phase of the B-MaP-C study

Abstract: Background: The B-MaP-C study aimed to determine alterations to breast cancer (BC) management during the peak transmission period of the UK COVID-19 pandemic and the potential impact of these treatment decisions. Methods: This was a national cohort study of patients with early BC undergoing multidisciplinary team (MDT)-guided treatment recommendations during the pandemic, designated ‘standard’ or ‘COVID-altered’, in the preoperative, operative and post-operative setting. Findings: Of 3776 patients (from 64 UK units) in the study, 2246 (59%) had ‘COVID-altered’ management. ‘Bridging’ endocrine therapy was used (n = 951) where theatre capacity was reduced. There was increasing access to COVID-19 low-risk theatres during the study period (59%). In line with national guidance, immediate breast reconstruction was avoided (n = 299). Where adjuvant chemotherapy was omitted (n = 81), the median benefit was only 3% (IQR 2–9%) using ‘NHS Predict’. There was the rapid adoption of new evidence-based hypofractionated radiotherapy (n = 781, from 46 units). Only 14 patients (1%) tested positive for SARS-CoV-2 during their treatment journey. Conclusions: The majority of ‘COVID-altered’ management decisions were largely in line with pre-COVID evidence-based guidelines, implying that breast cancer survival outcomes are unlikely to be negatively impacted by the pandemic. However, in this study, the potential impact of delays to BC presentation or diagnosis remains unknown

Lithostratigraphic setting of diagenetic, isotopic, and geochemistry studies of Ibexian and Whiterockian carbonate rocks of the St. George and Table Head groups, western Newfoundland

Diagenetic, isotopic and geochemical studies of Ibexian and Whiterockian carbonate rocks of the St. George and Table Head groups in western Newfoundland, are ongoing. This article summarizes the lithostratigraphy that plays host to the succession of shallow-shelf carbonates examined in shoreline sections near Port au Choix, and drill cores from Port au Choix and the Port au Port peninsulas. Ibexian to Whiterockian carbonate rocks of the upper St. George Group form a disconformity-bounded, third-order onlapofflap sequence; this being the last sequence to be deposited on the passive margin of Laurentia (in Newfoundland). Rocks of the Table Head Group preserve Whiterockian carbonate shelf deposits of the succeeding Anticosti foreland basin. The transition between the sequences is marked by the St. George Unconformity, an erosional karst unconformity fashioned by the dynamic interplay of Taconic orogenesis and eustatic sea-level fluctuation upon the local paleo-geography. The dolomitization of significant parts of the sequence is described within the context of the regional lithostratigraphy, and some geochemical, petrographic and isotopic results are summarized and presented here

Effect of nitrate supplementation on skeletal muscle motor unit activity during isometric blood flow restriction exercise

Background Nitrate (NO3-) supplementation has been reported to lower motor unit (MU) firing rate (MUFR) during dynamic resistance exercise, however its impact on MU activity during isometric and ischemic exercise is unknown.Purpose To assess the effect of NO3- supplementation on knee extensor MU activities during brief isometric contractions and a 3-min sustained contraction with blood flow restriction (BFR).Methods Sixteen healthy active young adults (six females) completed two trials in a randomized, double-blind, crossover design. Trials were preceded by 5 days of either NO3- (NIT) or placebo (PLA) supplementation. Intramuscular electromyography was used to determine the m.vastus lateralis MU potential (MUP) size, MUFR and near fibre (NF) jiggle (a measure of neuromuscular stability) during brief (20 s) isometric contractions at 25% maximal strength and throughout a 3 min sustained BFR isometric contraction.Results Plasma nitrite (NO2-) concentration was elevated after NIT compared to PLA (475±93 vs.198±46 nmol·L-1, p0.05), MUP duration was shorter with NIT compared to PLA during brief isometric contractions and the sustained ischemic contraction (pConclusion These findings provide insight into the effect of NO3- supplementation on MUP properties and reveal shorter MUP duration after short-term NO3- supplementation which may have potential positive implications for skeletal muscle contractile performance.</div