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1.
Article de Anglais | MEDLINE | ID: mdl-39102082

RÉSUMÉ

Water pollution with toxic hexavalent chromium, Cr(VI), is an environmental threat that has a direct impact on living organisms. The use of microorganisms from microbial mats to remove Cr(VI) has scarcely been investigated. Here, we isolated aerobic heterotrophic bacteria from a Cr-polluted microbial mat found in a mining site in Oman, and investigated their ability to remove Cr(VI), and the underlying mechanism(s) of removal. All isolates fell phylogenetically into the genera Enterobacter, Bacillus, and Cupriavidus, and could completely remove 1 mg L-1 Cr(VI) in 6 days. The strains could tolerate up to 2000 mg L-1 Cr(VI), and exhibited the highest Cr(VI) removal rate at 100 ± 9 mg L-1 d-1. Using scanning electron microscopy (SEM) coupled with elemental analysis, the strains were shown to adsorb Cr(VI) at their cell surfaces. The functional groups OH, NH2, Alkyl, Metal-O, and Cr(VI)-O were involved in the biosorption process. In addition, the strains were shown to reduce Cr(VI) to Cr(III) with the involvement of chromate reductase enzyme. We conclude that the aerobic heterotrophic bacteria isolated from Cr-polluted microbial mats use biosorption and bioreduction processes to remove Cr(VI) from wastewater.

2.
SAGE Open Med Case Rep ; 11: 2050313X231161440, 2023.
Article de Anglais | MEDLINE | ID: mdl-36968990

RÉSUMÉ

Eccrine angiomatous hamartoma is a rare, benign condition. Patients typically present with a solitary, sometimes enlarging nodule of the extremities usually appearing at birth or arising during childhood. Eccrine angiomatous hamartoma is usually sporadic, but one familial case of the multifocal variant has been reported. It is recognized histologically by increased numbers of eccrine elements as well as numerous vascular channels and proliferation of other dermal elements such as adipose tissue and hair follicles. When symptomatic, eccrine angiomatous hamartoma may be associated with hyperhidrosis or pain. We report a case of a 52-year-old woman with eccrine angiomatous hamartoma on the face and share our experience with botulinum toxins in the treatment of this condition.

3.
Sensors (Basel) ; 22(24)2022 Dec 08.
Article de Anglais | MEDLINE | ID: mdl-36559999

RÉSUMÉ

Design and implementation of an open-source-based supervisory control and data acquisition (SCADA) system for a community solar-powered reverse osmosis are presented in this paper. A typical SCADA system available on the market is proprietary and has a high initial and maintenance cost. Aside from that, there is no SCADA system with an alert system available to give users updates and status information concerning the system. The objective of this study is to develop a comprehensive SCADA design that takes advantage of open-source technology to address the world's most pressing problem, access to clean water. The designed reverse Osmosis system also uses renewable energy-based power sources. In this system, all data is stored and analyzed locally, which ensures the data is secure and allows the user to make data-driven decisions based on the collected data. Among the main components of this system are the field instrument devices (FIDs), the remote terminal unit (RTU), the main terminal units (MTUs), the web-based programming software, and the data analytics software. The Node-Red programming and dashboard tool, Grafana for data analytics, and InfluxDB for database management run on the main terminal unit having Debian operating system. Data is transmitted from the FIDs to the RTU, which then redirects it to the MTU via serial communication. Node-Red displays the data processed by the MTU on its dashboard as well, as the data is stored locally on the MTU and is displayed by means of Grafana, which is also installed on the same MTU. Through the Node-Red dashboard, the system is controlled, and notifications are sent to the community.


Sujet(s)
Logiciel , Énergie solaire , Eau , Technologie , Osmose
4.
J Cancer Allied Spec ; 8(2): 477, 2022.
Article de Anglais | MEDLINE | ID: mdl-37197568

RÉSUMÉ

Introduction: Asian developing countries share the burden of colorectal cancer (CRC) with rising mortality rates. This prospective study aims to apprehend the clinical relevance of age, gender, lifestyle choices (dietary habits and addiction) and body mass index (BMI) to the occurrence and progression of colon cancer (CC). Methods: A cohort of non-cancer (NC) and CC patients of South-Central Asian origin registered for screening colonoscopy or surgery at Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH and RC), Lahore, Pakistan, from 2015 to 2020 was identified. BMI (Kg/m2) was classified according to the World Health Organization criteria as underweight (<18.5 Kg/m2), normal weight (18.5-24.9 Kg/m2) and overweight (≥25 Kg/m2). Results: Among 236 participants, 99 (41.9%) belonged to the NC group, and 137 (58.1 %) participants had CC Overall, participants included 74 women and 162 men aged 20-85 years (mean ± SD; 49.9 ± 14.9). Notably, 46.0% of cancer patients had a family history of cancer. There was a direct relationship between CC with abnormal BMI (underweight and overweight), positive smoking history and positive family history of cancer. Conclusion: Being underweight or overweight is a potential risk factor for CC patients. The overall survival in patients with CC is clinically associated with lifestyle choices before CC diagnosis. A balanced diet, walking and other forms of exercise should be strongly recommended to the community and those undergoing screening colonoscopy.

5.
Cornea ; 41(2): 165-170, 2022 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-33859089

RÉSUMÉ

PURPOSE: To report the front corneal versus central and paracentral corneal changes after Bowman layer transplantation for keratoconus in a tertiary hospital in the United Kingdom. METHODS: Five eyes of 5 patients receiving Bowman layer transplant for advanced keratoconus in Royal Gwent Hospital (Newport, United Kingdom) were included. Preoperative and postoperative visual acuity; Kmax; Kmean, and corneal cylinder in the front cornea, 4.5 mm central, and 6 mm central; and corneal thickness were analyzed. RESULTS: Corneal flattening and reduction in corneal astigmatism was observed, more marked in the central and paracentral zone, allowing for improvement in best-corrected visual acuity with the aid of visual correction in 4 eyes. CONCLUSIONS: These results support previous data reporting Bowman layer transplantation as a useful strategy in the treatment of advanced keratoconus and suggest greater attention may be focused on central or paracentral corneal changes.


Sujet(s)
Cornée/imagerie diagnostique , Pachymétrie cornéenne/méthodes , Topographie cornéenne/méthodes , Transplantation de cornée/méthodes , Kératocône/chirurgie , Réfraction oculaire/physiologie , Adulte , Femelle , Études de suivi , Humains , Kératocône/diagnostic , Kératocône/physiopathologie , Mâle , Période postopératoire , Études rétrospectives , Résultat thérapeutique , Jeune adulte
6.
Explor Med ; 2: 146-166, 2021.
Article de Anglais | MEDLINE | ID: mdl-34723284

RÉSUMÉ

Nucleolin (NCL) is a multifunctional nucleolar phosphoprotein harboring critical roles in cells such as cell proliferation, survival, and growth. The dysregulation and overexpression of NCL are related to various pathologic and oncological indications. These characteristics of NCL make it an ideal target for the treatment of various cancers. AS1411 is a synthetic quadruplex-forming nuclease-resistant DNA oligonucleotide aptamer which shows a considerably high affinity for NCL, therefore, being capable of inducing growth inhibition in a variety of tumor cells. The high affinity and specificity of AS1411 towards NCL make it a suitable targeting tool, which can be used for the functionalization of therapeutic payloaddelivery nanosystems to selectively target tumor cells. This review explores the advances in NCL-targeting cancer therapy through AS1411-functionalized delivery nanosystems for the selective delivery of a broad spectrum of therapeutic agents.

7.
Ecancermedicalscience ; 15: 1197, 2021.
Article de Anglais | MEDLINE | ID: mdl-33889206

RÉSUMÉ

The aim of the study is to identify cornulin (CRNN) protein expression associated with advancement of tongue squamous cell carcinoma (TSCC). A comparison of addictive (containing potential carcinogens) versus non-addiction causative agents was expected to allow detection of differences in CRNN expression associated with TSCC. Bespoke tissue microarrays (TMAs) were prepared and immunohistochemistry (IHC) performed to determine the changes in CRNN expression in epithelial cells of node-negative (pN-), node-positive (pN+) TSCC and non-cancer patients' oral tissues. TMAs were validated by performing IHC on whole diagnostic tissues. Chi-square test or Fisher's-exact tests were used to establish significant expression differences. Analogous analyses were performed for biomarkers previously associated with TSCC, namely collagen I alpha 2 (COL1A2) and decorin (DCN) to compare the significance of CRNN. Keratinisation and its level (low, extensive) were studied in relation to CRNN so that the extent of squamous differentiation could better be assessed. IHC immunoreactive score (IRS) clustered the patients based on weak/moderate (Low (IRS ≤ +3)) or strong (High (IRS ≥ +4)) expression groups. A low expression was observed in a larger number of patients in control proteins COL1A2 (77.3%), DCN (87.5%) and target protein CRNN (52.3%), respectively. Low CRNN expression was observed in TSCC where nodes were involved (pN+: mean 1.4 ± 2.1) (p = 0.248). Keratinisation (%) was low (0% ≤ 50%) in 42.2% and extensive (1% ≥ 50.0%) in 57.8% patients. In conclusion, our study suggested that Low CRNN expression was associated with grade and lymph node metastasis in TSCC. CRNN expression is independent of addiction, however potentially carcinogenic addictive substances might be aiding in the disease progression.

8.
AIMS Microbiol ; 6(3): 183-203, 2020.
Article de Anglais | MEDLINE | ID: mdl-33134740

RÉSUMÉ

Emerging and re-emerging viral diseases poses a threat to living organisms, and led to serious concern to humankind and public health. The last two decades, viral epidemics such as the severe acute respiratory syndrome (SARS-CoV) reported in the years 2002-2003, and H1N1 influenza (Swine flu) in 2009, middle east respiratory syndrome (MERS-CoV) from Saudi Arabia in 2012, Ebola virus in 2014-2016, and Zika virus in 2015. The recent outbreak of 2019-CoV-2 or severe acute respiratory syndrome-2 (SARS-CoV-2), novel coronavirus (2019-nCoV, or 2019 disease, COVID-19) in Dec 2019, from, Wuhan city of China, has severe implications of health concerns to the whole world, due to global spread and high health risk. More than 423349 deaths had occurred globally and is still increasing every day. The whole world is under a health emergency, and people are advised to stay at their homes to avoid the spread of person-to-person infection, and advised to maintain social distancing. The advancement in clinical diagnosis techniques like Real-Time PCR (RT-PCR), immunological, microscopy, and geographic information system (GIS) mapping technology helped in tacking the rapid diagnosis and tracking viral infection in a short period. In the same way, artificial intelligence (AI), combinatorial chemistry, and deep learning approaches help to find novel therapeutics in less time and wide applicability in biomedical research. National Institute of Allergy and Infectious Diseases (NIAID) has started the clinical trials of investigation COVID-19 vaccine. Therefore, we can expect vaccines to be available for this deadly disease in the coming few months.

9.
J Immunol ; 204(10): 2840-2851, 2020 05 15.
Article de Anglais | MEDLINE | ID: mdl-32253240

RÉSUMÉ

Allogeneic islet transplantation is limited by adverse effects of chronic immunosuppression used to control rejection. The programmed cell death 1 pathway as an important immune checkpoint has the potential to obviate the need for chronic immunosuppression. We generated an oligomeric form of programmed cell death 1 ligand chimeric with core streptavidin (SA-PDL1) that inhibited the T effector cell response to alloantigens and converted T conventional cells into CD4+Foxp3+ T regulatory cells. The SA-PDL1 protein was effectively displayed on the surface of biotinylated mouse islets without a negative impact islet viability and insulin secretion. Transplantation of SA-PDL1-engineered islet grafts with a short course of rapamycin regimen resulted in sustained graft survival and function in >90% of allogeneic recipients over a 100-d observation period. Long-term survival was associated with increased levels of intragraft transcripts for innate and adaptive immune regulatory factors, including IDO-1, arginase-1, Foxp3, TGF-ß, IL-10, and decreased levels of proinflammatory T-bet, IL-1ß, TNF-α, and IFN-γ as assessed on day 3 posttransplantation. T cells of long-term graft recipients generated a proliferative response to donor Ags at a similar magnitude to T cells of naive animals, suggestive of the localized nature of tolerance. Immunohistochemical analyses showed intense peri-islet infiltration of T regulatory cells in long-term grafts and systemic depletion of this cell population resulted in prompt rejection. The transient display of SA-PDL1 protein on the surface of islets serves as a practical means of localized immunomodulation that accomplishes sustained graft survival in the absence of chronic immunosuppression with potential clinical implications.


Sujet(s)
Allogreffes/physiologie , Antigène CD274/métabolisme , Diabète de type 1/immunologie , Immunosuppression thérapeutique/méthodes , Ilots pancréatiques/physiologie , Streptavidine/métabolisme , Lymphocytes T régulateurs/immunologie , Animaux , Antigène CD274/génétique , Différenciation cellulaire , Survie cellulaire , Facteurs de transcription Forkhead/métabolisme , Humains , Tolérance immunitaire , Immunité/génétique , Immunomodulation , Transplantation d'ilots de Langerhans , Souris , Souris de lignée BALB C , Souris de lignée C3H , Souris de lignée C57BL , Protéines de fusion recombinantes/génétique , Streptavidine/génétique
10.
Cancers (Basel) ; 12(2)2020 Feb 13.
Article de Anglais | MEDLINE | ID: mdl-32069844

RÉSUMÉ

Melanoma is the most aggressive form of skin cancer. Hypoxia is a feature of the tumor microenvironment that reduces efficacy of immuno- and chemotherapies, resulting in poor clinical outcomes. Lactococcus lactis is a facultative anaerobic gram-positive lactic acid bacterium (LAB) that is Generally Recognized as Safe (GRAS). Recently, the use of LAB as a delivery vehicle has emerged as an alternative strategy to deliver therapeutic molecules; therefore, we investigated whether L. lactis can target and localize within melanoma hypoxic niches. To simulate hypoxic conditions in vitro, melanoma cells A2058, A375 and MeWo were cultured in a chamber with a gas mixture of 5% CO2, 94% N2 and 1% O2. Among the cell lines tested, MeWo cells displayed greater survival rates when compared to A2058 and A375 cells. Co-cultures of L. lactis expressing GFP or mCherry and MeWo cells revealed that L. lactis efficiently express the transgenes under hypoxic conditions. Moreover, multispectral optoacoustic tomography (MSOT), and near infrared (NIR) imaging of tumor-bearing BALB/c mice revealed that the intravenous injection of either L. lactis expressing ß-galactosidase (ß-gal) or infrared fluorescent protein (IRFP713) results in the establishment of the recombinant bacteria within tumor hypoxic niches. Overall, our data suggest that L. lactis represents an alternative strategy to target and deliver therapeutic molecules into the tumor hypoxic microenvironment.

11.
J Coll Physicians Surg Pak ; 30(2): 113-122, 2020 Feb.
Article de Anglais | MEDLINE | ID: mdl-32036815

RÉSUMÉ

OBJECTIVE: To study the cancer incidence rates in Lahore, which has an estimated annual population count of 10.3 million. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Data on new cancer cases diagnosed between 2010 and 2015, among the residents of Lahore district, Pakistan, was reviewed retrospectively in 2015-2017. METHODOLOGY: Nineteen collaborating centres of the population-based Punjab Cancer Registry (PCR), representing both the government and private sectors, reported their cases to the coordinating office located within the Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC). The age-standardised incidence rates (ASIR) per 100,000 population, over a six-year period, were computed. Sixteen 5-year age groups were created beginning from 0-4 to 70-74 years, followed by 75+ years. Graphs on the five-year age-specific incidence rates by gender, were also generated. RESULTS: Between 2010 and 2015, 33,028 new malignancies were recorded in Lahore, with the crude average annual incidence rate being 53.1. In adults, the highest ASIRs were noted for cancers of the breast (77.3) among females and of prostate (11.4) in men. Age-specific incidence rates for female breast cancer showed an upward trend at the age of 20 years, reaching a figure of 160 at the age of 55 years. Among males, the rates for prostate cancer started to increase at the age of 55 years and reached a peak of 93 at 75 years. CONCLUSION: These results warrant expanding cancer registration in the region and sharing statistics with policy-makers to establish hospitals accordingly to manage cancer, along with exploring various risk factors within the population.


Sujet(s)
Tumeurs/épidémiologie , Surveillance de la population , Enregistrements , Adolescent , Adulte , Répartition par âge , Sujet âgé , Études transversales , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Morbidité/tendances , Pakistan/épidémiologie , Études rétrospectives , Facteurs de risque , Répartition par sexe , Taux de survie/tendances , Jeune adulte
12.
Nanomaterials (Basel) ; 9(5)2019 May 07.
Article de Anglais | MEDLINE | ID: mdl-31067749

RÉSUMÉ

Gold nanoparticles (GNPs) have tremendous potential as cancer-targeted contrast agents for diagnostic imaging. The ability to modify the particle surface with both disease-targeting molecules (such as the cancer-specific aptamer AS1411) and contrast agents (such as the gadolinium chelate Gd(III)-DO3A-SH) enables tailoring the particles for specific cancer-imaging and diagnosis. While the amount of image contrast generated by nanoparticle contrast agents is often low, it can be augmented with the assistance of computer image analysis algorithms. In this work, the ability of cancer-targeted gold nanoparticle-oligonucleotide conjugates to distinguish between malignant (MDA-MB-231) and healthy cells (MCF-10A) is tested using a T1-weighted image analysis algorithm based on three-dimensional, deformable model-based segmentation to extract the Volume of Interest (VOI). The gold nanoparticle/algorithm tandem was tested using contrast agent GNP-Gd(III)-DO3A-SH-AS1411) and nontargeted c-rich oligonucleotide (CRO) analogs and control (CTR) counterparts (GNP-Gd(III)-DO3A-SH-CRO/CTR) via in vitro studies. Remarkably, the cancer cells were notably distinguished from the nonmalignant cells, especially at nanomolar contrast agent concentrations. The T1-weighted image analysis algorithm provided similar results to the industry standard Varian software interface (VNMRJ) analysis of T1 maps at micromolar contrast agent concentrations, in which the VNMRJ produced a 19.5% better MRI contrast enhancement. However, our algorithm provided more sensitive and consistent results at nanomolar contrast agent concentrations, where our algorithm produced ~500% better MRI contrast enhancement.

13.
Clin Case Rep ; 7(4): 797-800, 2019 Apr.
Article de Anglais | MEDLINE | ID: mdl-30997088

RÉSUMÉ

Subclavian artery aneurysms are uncommon and present a diagnostic dilemma. Our patient attended with life-threatening rupture, requiring prompt management. However, lack of on-site facilities and specialist input posed a logistical challenge. The patient was stable enough to allow an urgent transfer to a specialist unit for successful endovascular repair.

14.
J Pak Med Assoc ; 69(3): 389-398, 2019 Mar.
Article de Anglais | MEDLINE | ID: mdl-30890833

RÉSUMÉ

OBJECTIVE: The study aimed to evaluate literature on rheumatoid arthritis disease in Pakistani patients, to have an understanding about its epidemiology, clinical aspects and socio-economic determinants. METHODS: The review study was conducted from December 2017, to May 2018. An online search was conducted in international and local health databases using appropriate search keywords as well as scanning reference lists of related articles. Literature published after year 2000 that reported epidemiological, demographic, clinical and socioeconomic data of Pakistani rheumatoid arthritis patients was included. Meta-analysis was performed where possible. This systematic review was registered on the international prospective register of systematic reviews PROSPERO (CRD42018090582). RESULTS: Of the 334 research articles found, 29 (8.7%) were selected. Patients were mostly females, but no study explored impact of disease on household and family role functioning of rheumatoid arthritis-affected women in Pakistan. Most patients were uneducated (55%) and unemployed; had low disease knowledge (N = 149, 74.5%) and poor adherence to disease-modifying anti-rheumatic drugs (N = 23, 23%). Point prevalence of rheumatoid arthritis reported from Karachi was high at 26.9%. Moderate disease activity, i.e., 4.5}0.7 and mild functional disability (N = 66, 51.6%) were seen in RA patients. Almost half (N = 799, 46.9%) had comorbidities. Almost a fifth proportion of RA patients had dyslipidaemia as a comorbidity (N = 134, 16.77%) and higher cardiovascular risk score as modifiable risk factor. Undiagnosed depression (N = 134, 58.3%) and low bone mineral density (N = 93, 40.6%) were reported in RA patients. Direct monthly treatment cost of disease was significantly high considering patients' socio-economic status, i.e., USD 16.47 - 100.68. Most commonly used drug was methotrexate. CONCLUSIONS: There is a paucity of data on Pakistani rheumatoid arthritis patients' demographic and socio-economic parameters, especially the gender element.


Sujet(s)
Polyarthrite rhumatoïde/épidémiologie , Antirhumatismaux/économie , Antirhumatismaux/usage thérapeutique , Polyarthrite rhumatoïde/traitement médicamenteux , Polyarthrite rhumatoïde/économie , Maladies osseuses métaboliques/épidémiologie , Maladies cardiovasculaires/épidémiologie , Comorbidité , Coûts indirects de la maladie , Dépression/épidémiologie , Trouble dépressif/épidémiologie , Fibromyalgie/épidémiologie , Méthotrexate/économie , Méthotrexate/usage thérapeutique , Ostéoporose/épidémiologie , Pakistan/épidémiologie , Prévalence , Facteurs de risque , Classe sociale
15.
Biol Reprod ; 100(4): 917-938, 2019 04 01.
Article de Anglais | MEDLINE | ID: mdl-30423016

RÉSUMÉ

Endometriosis is a prevalent gynecological disorder that eventually gives rise to painful invasive lesions. Increased levels of transforming growth factor-beta 1 (TGF-B1) have been reported in endometriosis. However, details of the effects of high TGF-B1 on downstream signaling in ectopic endometrial tissue remain obscure. We induced endometriotic lesions in mice by surgical auto-transplantation of endometrial tissues to the peritoneal regions. We then treated endometriotic (ectopic and eutopic endometrial tissues) and nonendometriotic (only eutopic endometrial tissues) animal groups with either active TGF-B1 or PBS. Our results demonstrate that externally supplemented TGF-B1 increases the growth of ectopically implanted endometrial tissues in mice, possibly via SMAD2/3 activation and PTEN suppression. Adhesion molecules integrins (beta3 and beta8) and FAK were upregulated in the ectopic endometrial tissue when TGF-B1 was administered. Phosphorylated E-cadherin, N-cadherin, and vimentin were enhanced in the ectopic endometrial tissue in the presence of TGF-B1 in the mouse model, and correlated with epithelial-mesenchymal transition (EMT) in ovarian endometriotic cells of human origin. Furthermore, in response to TGF-B1, the expression of RHOGTPases (RAC1, RHOC, and RHOG) was increased in the human endometriotic cells (ovarian cyst derived cells from endometriosis patient) and tissues from the mouse model of endometriosis (ectopic endometrial tissue). TGF-B1 enhanced the migratory, invasive, and colonizing potential of human endometriotic cells. Therefore, we conclude that TGF-B1 potentiates the adhesion of ectopic endometrial cells/tissues in the peritoneal region by enhancing the integrin and FAK signaling axis, and also migration via cadherin-mediated EMT and RHOGTPase signaling cascades.


Sujet(s)
Adhérence cellulaire/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Endométriose/anatomopathologie , Maladies du péritoine/anatomopathologie , Facteur de croissance transformant bêta-1/pharmacologie , Adhésivité/effets des médicaments et des substances chimiques , Animaux , Études cas-témoins , Cellules cultivées , Modèles animaux de maladie humaine , Évolution de la maladie , Relation dose-effet des médicaments , Endométriose/sang , Transition épithélio-mésenchymateuse/effets des médicaments et des substances chimiques , Transition épithélio-mésenchymateuse/physiologie , Femelle , Humains , Souris , Maladies du péritoine/sang , Protéines recombinantes/pharmacologie , Facteur de croissance transformant bêta-1/sang
16.
Entropy (Basel) ; 20(2)2018 Jan 30.
Article de Anglais | MEDLINE | ID: mdl-33265183

RÉSUMÉ

Uplink and Downlink channel estimation in massive Multiple Input Multiple Output (MIMO) systems is an intricate issue because of the increasing channel matrix dimensions. The channel feedback overhead using traditional codebook schemes is very large, which consumes more bandwidth and decreases the overall system efficiency. The purpose of this paper is to decrease the channel estimation overhead by taking the advantage of sparse attributes and also to optimize the Energy Efficiency (EE) of the system. To cope with this issue, we propose a novel approach by using Compressed-Sensing (CS), Block Iterative-Support-Detection (Block-ISD), Angle-of-Departure (AoD) and Structured Compressive Sampling Matching Pursuit (S-CoSaMP) algorithms to reduce the channel estimation overhead and compare them with the traditional algorithms. The CS uses temporal-correlation of time-varying channels to produce Differential-Channel Impulse Response (DCIR) among two CIRs that are adjacent in time-slots. DCIR has greater sparsity than the conventional CIRs as it can be easily compressed. The Block-ISD uses spatial-correlation of the channels to obtain the block-sparsity which results in lower pilot-overhead. AoD quantizes the channels whose path-AoDs variation is slower than path-gains and such information is utilized for reducing the overhead. S-CoSaMP deploys structured-sparsity to obtain reliable Channel-State-Information (CSI). MATLAB simulation results show that the proposed CS based algorithms reduce the feedback and pilot-overhead by a significant percentage and also improve the system capacity as compared with the traditional algorithms. Moreover, the EE level increases with increasing Base Station (BS) density, UE density and lowering hardware impairments level.

17.
Sensors (Basel) ; 15(10): 25868-81, 2015 Oct 13.
Article de Anglais | MEDLINE | ID: mdl-26473870

RÉSUMÉ

We numerically and experimentally investigated the lateral coupling between photonic crystal (PhC) nanobeam (NB) cavities, pursuing high sensitivity and figure of merit (FOM) label-free biosensor. We numerically carried out 3D finite-difference time-domain (3D-FDTD) and the finite element method (FEM) simulations. We showed that when two PhC NB cavities separated by a small gap are evanescently coupled, the variation in the gap width significantly changes the coupling efficiency between the two coupled NB cavities and the resulting resonant frequencies split. Experimentally, we fabricated laterally-coupled PhC NB cavities using (InGaAsP) layer on the InP substrate. For sensing, we showed that the laterally coupled PhC NB cavities sensor exhibits higher sensitivity than the single PhC NB cavity. The higher sensitivity of laterally coupled PhC NB cavities is due to the strong evanescent coupling between nearby PhC NB cavities, which depends on the gap width and it is attributed to the large confinement of the electromagnetic field in the gap (air or liquid). As a result of the lateral coupling, both even (symmetric) and odd (asymmetric) modes exist. We show that even modes are more sensitive than odd modes. In addition, higher-order modes exhibit higher sensitivity. Hence, we characterized and examined the fabricated PhC NB cavity as a label-free biosensor, and it exhibits high figure of merit due to its high Q-factor. This illustrates a potentially useful method for optical sensing at nanoscale.


Sujet(s)
Techniques de biocapteur/instrumentation , Nanotechnologie/instrumentation , Nanotechnologie/méthodes , Optique et photonique/instrumentation , Simulation numérique , Réfractométrie
18.
Asia Pac J Ophthalmol (Phila) ; 4(5): 259-62, 2015.
Article de Anglais | MEDLINE | ID: mdl-26431208

RÉSUMÉ

PURPOSE: The aim of this study was to determine the efficacy and safety of scleral buckling surgery in retinal detachment due to retinal dialysis. DESIGN: This study was a prospective, interventional case series. METHODS: A total of 48 eyes of 48 consecutive patients were included after obtaining informed written consent. Besides taking a thorough history, all eyes were examined by a retinal surgeon. The macula status, site, and extent of retinal dialysis and rhegmatogenous retinal detachment (RRD) were particularly noted. Proliferative vitreoretinopathy grading was done. Buckling was performed by a single surgeon. At every follow-up, visual acuity, intraocular pressure, retina status, and buckle position were noted. Any complication found was recorded. Follow-up was done for at least 6 months. SPSS version 16 was used for data analysis. RESULTS: We included 48 cases of RRD due to retinal dialysis. The mean ± SD age of the patients was 26.85 ± 15.1 years. The macula was detached in 85.4% of the cases, and proliferative vitreoretinopathy grade C was found in 25% of the cases. A surgical reattachment rate of 95.8% was attained after a single primary buckling procedure. Final Snellen best-corrected visual acuity of 6/18 or better was attained in 12.5% of the cases. However, 62.5% of the cases had best-corrected visual acuity in the range of 6/24 to 6/60. Subretinal hemorrhage occurred in 8.3% of cases intraoperatively after subretinal fluid drainage. CONCLUSIONS: We conclude that scleral buckling has a definite role in the management of RRD due to retinal dialysis.


Sujet(s)
Décollement de la rétine/chirurgie , Perforations de la rétine/chirurgie , Indentation sclérale , Adolescent , Adulte , Tamponnement interne , Femelle , Humains , Mâle , Adulte d'âge moyen , Études prospectives , Décollement de la rétine/étiologie , Perforations de la rétine/complications , Acuité visuelle/physiologie , Vitrectomie , Jeune adulte
20.
Pharmacogn Mag ; 11(Suppl 1): S182-9, 2015 May.
Article de Anglais | MEDLINE | ID: mdl-26109765

RÉSUMÉ

BACKGROUND: Nigella sativa Linn. which has many acclaimed medicinal properties is an indigenous herbaceous plant and belongs to the Ranunculaceae family, which grows in countries bordering the Mediterranean Sea, Pakistan and India. OBJECTIVE: This study was designed to investigate the effects of N. sativa seed extracts of different germination phases on the central nervous system (CNS) responses in experimental animals. MATERIALS AND METHODS: Anxiolytic, locomotor activity of extracts (1 g/kg of body weight) was evaluated in both stressed and unstressed animal models and antiepileptic effect was evaluated by maximal electroshock seizure model keeping diazepam (20 mg/kg) as a positive control. Antidepressant effect was evaluated by forced swim test and tail suspension test keeping imipramine (15 mg/kg) as a positive control. RESULTS: All tested extracts of N. sativa during different phases of germination (especially 5(th) day germination phase) showed significant (P < 0.001) anxiolytic effect in comparison to control. Diazepam reduced locomotor activity in control (unstressed) rats but did not show affect in stressed rats while N. sativa extracts from germination phases significantly (P < 0.001) reduced locomotor activity in unstressed as well as stressed animals. All the extracts of N. sativa from different germination phases exhibited significant (P < 0.001) reduction in various phases of epileptic seizure on comparison with the reference standard (diazepam). During antidepressant test, N. sativa extracts exhibited a slight reduction in the immobility of rats. CONCLUSION: During germination, especially in 5(th) day germination extract, N. sativa showed significant CNS depressant activity as compared to whole seeds that possibly may be due higher content of secondary metabolites produced during germination.

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