Bulletin of Computer Science and Electrical Engineering (BCSEE)
Not a member yet
26405 research outputs found
Sort by
Catalytic Activation of Nanoparticles Using Light
No full textIn recent years, catalytic activation of nanoparticles (NPs) using light has emerged as a promising strategy to elucidate some of the challenges faced in environmental remediation, energy conversion, and biomedicine. Among these strategies, metal oxide NPs have been extensively utilized. The work detailed in this dissertation are in two-folds. First, some heterogenous metal oxide photocatalysts were employed towards the degradation of toxic environmental pollutants. The photocatalytic activity of all these metal oxides were enhanced by (i) surface decorating with Pd cocatalyst, and (ii) designing heterojunctioned structures. Specifically, an ultrasound-assisted synthetic route was employed for the generation of different defined sizes of SrTiO3 NPs. These were subsequently coated with Pd NPs for the photocatalytic degradation of model organic pollutants. Taking it further, semiconductor-semiconductor heterostructures like BiVO4/BiOX, and SrTiO3/BiOBr materials were explored for environmental remediation applications. A ternary composite was achieved by the addition of Pd NPs. As a result, significant enhancement in reactivity was observed. The second part of the work presented here focused on the optical manipulation of peptide capped Au NPs via a photoswitchable molecule such as azobenzene for catalysis. The catalytic activity of the NPs changed based on the isomerization state of incorporated azobenzene unit in the peptide ligand. The catalytic activity was performed by placing the azobenzene ligand design at either the N- or C- terminus of the parent peptide (AuBP1). Using different wavelengths of light, the peptide-ligand unit can be switched to either trans or cis, where they were employed for the reduction of monosubstituted and disubstituted nitrophenols.These variations revealed different catalytic responses based on the photoswitch conformation, position, and substrate in use.Taken together, this work demonstrates the capabilities of different photo activated nanomaterials with applications in biomedicine and environmental remediation. </p
Relative frequency of avascular necrosis of the hip as indication for primary Total Hip Arthroplasty in the USA vs. India
No full textIntroduction: Background: Primary total hip arthroplasty (THA) is performed for a variety of pathologies. Oste-oarthritis (OA) is the most common indication for THA in the United States of America (USA). The study aims to establish the incidence of indications for THA in the USA as compared to India and to assess whether Avascular Necrosis (AVN) of the Hip is a more frequent indication for THA in India than in the USA. Methods: The National Inpatient Sample database (USA) and two Indian databases (one national and one regional) were analyzed to identify all patients who underwent primary THA within the databases. The relative frequencies of each indication for THA were determined. The patients' demographics and risk factors for AVN of the hip were recorded and assessed. The data were then compared across the patients in the USA and the patients in India. Results: 225,061 primary THA patients were identified in the USA database and 20,288 in the Indian database. The proportion of primary THA performed for AVN in the American database (5.97%) was significantly lower than the proportion of THA performed for AVN in the Indian database (51.8%). Conclusion: The relative frequency of AVN as an indication for THA is significantly higher in India than in the USA. It is important to recognize the differences in relative indications for THA between world populations, as outcomes after THA among Eastern populations of the world may not be equivalent to ones seen in their Western counterparts
Investigating sensitivity of ozone to emission reductions in the New York City (NYC) metropolitan and downwind areas
No full textOzone sensitivity to emission changes in urban environments were examined using WRF and CAMx simulations for the New York City metropolitan area (NYC) with data from the 2018 Long Island Sound Tropospheric Ozone Study measurements. The WRF simulation showed large positive biases of windspeed over entire domain, but those were significantly reduced with observational nudging. The base CAMx simulation showed large positive bias for NO2 concentrations in NYC, which was corrected after NOx emission adjustment (22% reduction) based on previous work. The improved modeling platform demonstrated reliable performance skills for regulatory applications. Pollution transport from NYC to the downwind region were well captured by the model. Simulated ozone concentration increases in response to NOx emission reductions within NYC proximity suggested this area to be a VOC-limited ozone formation regime. Reducing anthropogenic emissions by 50% for all pollutants reduced the number of simulated ozone exceedances from 18 to 9 days for NYC. Emission reductions were even more effective for air quality improvements in the downwind region with ozone exceedances decreasing from 20 to 7 days. Source apportionment showed mobile and industrial solvent emission sectors to be contributing more to ozone exceedances than the electrical generating units (EGU) sector in both NYC and the downwind region. The largest air quality improvement appeared to be associated with VOC emission reductions from the industrial solvent sector. All source sectors yielded higher ozone production efficiency when emissions were reduced by 50%, suggesting remaining emissions can be more potent in producing ozone per molecule of NOx.
•We examine ozone sensitivity to emission changes in NYC using WRF-CAMx.•Large positive wind biases were reduced using observational nudging.•NYC was shown to be VOC-limited ozone formation regime.•Reducing man-made emissions by 50% significantly improved ozone concentrations.•Ozone production efficiency increased when emissions decreased
Longitudinal impact of stressful life events on HIV-related risk and psychosocial problems among MSM in Chennai and Mumbai, India
No full textBackground Studies show that stressful life events (SLE) (e.g., discrimination, financial problems) can lead to psychosocial problems and exacerbate condomless anal sex (CAS) without protection via pre-exposure prophylaxis (PrEP) among men who have sex with men. However, few studies have examined this relationship among men who have sex with men in India, and none have examined this longitudinally. Methods As a part of an HIV-prevention intervention, 608 MSM from Chennai and Mumbai, India, completed behavioral surveys at baseline, 4, 8, and 12 months. We used longitudinal generalized estimating equations (GEE) modeling to examine the relationship between SLE and its severity and subsequent psychosocial problems, CAS, and history of diagnosed sexually transmitted infection (STI). All models are adjusted for age, sexual identity, intervention arm, human immunodeficiency virus status, and recruitment city. Results The number of SLE and their corresponding perceived impact score remained consistent at each time point. In multivariable GEE models, the number of SLE was predictive of CAS, depression, and harmful drinking. Similarly, the ratio of the impact of SLE was predictive of CAS, depression, and diagnosed STI. However, harmful drinking was not predictive in this model. Conclusions These findings provide evidence that can inform future interventions, which can be used to enhance self-acceptance, coping skills, and other forms of resiliency
How Transparent Internal Communication From CEO, Supervisors, and Peers Leads to Employee Advocacy
No full textThe purpose of this study is to examine the role of transparent internal communication from multiple communication entities within organizations-CEO, supervisors, and peers-in employees' internal and external advocacy, respectively, with a consideration of the two mediators: employee-organization relationship (EOR) and employee empowerment. Results of an online survey with 403 full-time employees in the United States suggested that transparent communication from direct supervisors was positively related to employee advocacy via heightened EOR and empowerment. In addition, positive associations between CEOs' transparent communication and employees' external and internal advocacy via a favorable EOR were found, while transparent peer communication was positively related to employee advocacy through empowerment. Theoretical and practical implications for strategic internal communication are discussed
Nasal Cavity Squamous Cell Carcinoma: Factors Associated With Treatment Outcomes and Potential Organ Preservation
No full textBackground Squamous cell carcinoma of the nasal cavity (NCSCC) is a rare, challenging malignancy. Surgical resection of this tumor can cause significant facial deformity, and indications for adjuvant or organ preservation therapies are not well-described. Objective To examine the impact of treatment regimen on survival outcomes in NCSCC and to compare surgical to non-surgical based therapies. Methods The National Cancer Database was queried for NCSCC from 2004 to 2014. Patient demographics, tumor characteristics, and treatment regimen were compared for the entire cohort. Multivariable Cox proportional hazards regression was performed for statistical analysis of treatment regimen and surgical margins on overall survival (OS) for early and late-stage disease. Results A total of 1883 NCSCC patients were identified. The OS for the cohort was 83 months, and median age at diagnosis was 65 years. NCSCC patients who underwent surgery followed by adjuvant radiation therapy (RT) had a better OS compared to definitive RT (HR: 0.58, P < .001). In early stage NCSCC (T1/T2, N0), there was no significant difference in OS between patients treated with surgery only or surgery with adjuvant RT compared to definitive RT. In advanced stage NCSCC, surgery with adjuvant RT had a better OS compared to definitive chemoradiation. Having positive margins was shown to predict a worse OS when compared to negative margins in surgical patients despite adjuvant RT or chemoradiation. Conclusions NCSCC appears to be best treated with surgery followed by adjuvant RT in advanced-stage disease whereas in early-stage disease, surgery does not improve OS compared to definitive RT
Phase 2, multicenter, randomized study of salvage radiation therapy +/- metformin for recurrent prostate cancer after radical prostatectomy (SAKK 08/15 – GETUG-AFU 34 PROMET trial)
No full text353 Background: Pre-clinical and retrospective clinical data support an interaction of metformin (MET) and radiotherapy. Thus, MET may represent a cost-effective means to improve radiotherapy outcomes. We sought to investigate whether MET increases time to progression (TTP) when combined with salvage radiation therapy (SRT) in men with recurrent prostate cancer after radical prostatectomy (RP). Methods: Non-diabetic men with biochemical recurrence after RP were enrolled into an open label, randomized, phase 2 study in 17 hospitals in Switzerland, France, and Germany. The randomization (1:1) was stratified by Gleason score ( 0.5 vs ≤ 0.5 ng/mL), ADT use, and evidence of local recurrence. Following randomization, patients received either prostate bed SRT (70Gy) or prostate bed SRT (70Gy) + MET. MET 850mg PO QD was given for 4 weeks before SRT, then 850mg PO QD for 48 weeks. The primary endpoint was TTP. Secondary endpoints were progression-free survival, undetectable PSA under normal testosterone levels, 50% PSA response, clinical progression-free survival, time to further systemic therapy, prostate cancer-specific survival, overall survival, and adverse events (AE). The trial design was powered for a HR 0.65 with planned enrollment of 170 patients. The trial was prematurely closed by the sponsor due to financial reasons. Data is reported after patients reached a minimum follow-up of 12 months after SRT and corresponds to the final analysis. Results: A total of 111 patients were randomized (106 evaluable) between 10/2017 and 11/2020. The median PSA at randomization was 0.3 ng/mL (range, 0.03-1.5 ng/mL), 19 patients (17.9%) had Gleason ≥8, 54 (50.9%) pT3 disease, and 50 (47.2%) positive surgical margins. Twenty-four patients (22.6%) used short-term ADT. Trial arms were well balanced. At a median follow-up of 27.1 months (95% CI: 26.7-27.8), a total of 16 progression events occurred. The median TTP was not reached in either treatment arm. The hazard ratio adjusted by stratification factors was 1.25 (95% CI: 0.40-3.94; one-sided 80% CI: 2.05; log-rank p=0.62). Two-year TTP was 89% (95% CI: 76%-96%) in the SRT arm vs 82% (95% CI: 67%-91%) in the SRT + MET arm. No statistically significant differences were found for the secondary endpoints. Most common AE during treatment was grade 1-2 diarrhea (24.1% SRT vs 54.6% SRT + MET). Grade 2 and 3 AE (gastrointestinal and/or urinary) were 25.9% and 3.7% with SRT vs 34.5% and 7.3% with SRT + MET (p=0.41 and p=0.68), respectively. Conclusions: Adding MET to SRT did not result in a significant improvement in TTP in non-diabetic men with recurrent prostate cancer post-RP. Because of early trial closure and fewer than expected events, the trial may have been underpowered for this endpoint. Additional correlative studies will be pursued. Clinical trial information: NCT02945813
Characteristics, Risk Factors, and Outcome of New-onset Systolic Heart Failure After Liver Transplantation: A Single-center Cohort
No full textNew-onset systolic heart failure (HF) after liver transplantation (LT) is a significant cause of morbidity and mortality; however, its characteristics are still insufficiently delineated. HF may involve the left ventricle (LV), right ventricle (RV), or both ventricles. We explored the incidence, characteristics, etiologies, risks, involved cardiac chambers, and outcomes of HF after LT
Comparison Between B-Scan and En Face Images for Incomplete and Complete Retinal Pigment Epithelium And Outer Retinal Atrophy
No full textPurpose: To evaluate and compare the detection of incomplete retinal pigment epithelium and outer retinal atrophy (iRORA) and complete retinal pigment epithelium and outer retinal atrophy (cRORA) assessed on OCT B-scans versus persistent choroidal hypertransmission defects (hyperTDs) assessed by en face choroidal OCT images.Design: Retrospective, cross-sectional study. Participants: Patients with late atrophic age-related macular degeneration imaged on the same day using both Spectralis OCT and Cirrus OCT.Main Outcome Measure: Agreement between the B-scan and en face OCT for the detection of hyperTDs, cRORA, and iRORA.Methods: Two independent graders examined en face OCT and structural OCT to determine the presence and location of hyperTDs, iRORA, and cRORA.Results: A total of 239 iRORA and cRORA lesions were detected on the B-scans, and 249 hyperTD lesions were identified on the en face OCT images. There was no significant difference (P = 0.88) in the number of lesions. There was no significant difference in the 134 cRORA lesions identified on B-scans and the 131 hyperTDs detected on en face OCT images (P = 0.13). A total of 105 iRORA lesions were identified by B-scan assessment; however, 50 of these iRORA lesions met the criteria for persistent hyperTDs on en face OCT images (P = 250 mm in a nonhorizontal en face dimension.(c) 2023 by the American Academy of Ophthalmology</p
