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1.
Comput Methods Programs Biomed ; 226: 107156, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36265290

ABSTRACT

BACKGROUND AND OBJECTIVE: Due to the low toxicity, unique physiochemical properties, and appropriate surface modifications, Carbon Nanotubes (CNTs) are used as target carriers in drug delivery systems. In the present problem, we have considered both single-walled and multi-walled CNTs to study the impact of irreversibility on the micropolar nanofluid flow through a squeezing channel with the base fluid blood. The blood is considered a micropolar fluid in the presence of different blood cells and their rotational nature. Further, blood is influenced by the external magnetic field parallel to the microrotation along with viscous and Joule dissipations. METHOD: Highly coupled and nonlinear partial differential equations are solved with Homotopy Analysis Method (HAM) after simplified equations using similarity transformation. Further, we have concluded the minimum squared residual errors to show the method's accuracy. A comparison made with the existing literature and shows a good agreement. RESULTS: The angular velocity of the fluid particles is enhanced by increasing the squeezing number. In the case of the squeezing, volume fraction has improved the viscous drag and is found high for MWCNT embedded nanofluid. The heat transfer rate is higher for the MWCNT embedded nanofluid than the SWCNT embedded nanofluid. A descent found in entropy generation boosts up with the Brinkman parameter while opposite phenomena appear for radiation and Hartman number and vortex viscosity. Both Bejan number and entropy generation profiles are restricted with an increase in vortex viscosity. CONCLUSION: SWCNTs are showed to be more effective and efficient than the MWCNTs in elevating velocity, temperature and irreversibility of the system. Outcomes of this problem will help to understand the implementation of the drug carrier and irreversibility phenomena during drug delivery.


Subject(s)
Models, Theoretical , Nanotubes, Carbon , Algorithms , Entropy , Viscosity
2.
Article in English | MEDLINE | ID: mdl-24747848

ABSTRACT

Manganese doped ZnO/Zn2SiO4 (MZS) composite phosphors were successfully prepared by conventional solid state reaction method. The structural and optical properties of as-prepared samples were analysed by means of XRD, SEM, PLE and PL. The result shows that the samples consist of both ZnO and ZnSiO4 phases which confirms the composite phosphor. The strain acting on the phosphor is found to be in the range of 0.0040-0.0058 for different concentration of Mn(2+) doping. The doping of Mn(2+) significantly influences the optical properties of phosphor. Under 266 nm laser excitation samples show green emission (∼530 nm) and with 355 nm laser excitation blue emission (∼441 nm) is shown. The enhancement of luminescence intensity is achieved with Mn(2+) doping up to an optimum concentration (10 at.%) and then decreases. On 266 nm excitation, blue emission intensity decreases with Mn(2+) doping. This composite phosphor shows both blue and green emission under different excitations.


Subject(s)
Luminescent Agents/chemistry , Manganese/chemistry , Silicon Compounds/chemistry , Zinc Oxide/chemistry , Luminescence , Luminescent Agents/chemical synthesis , Silicon Compounds/chemical synthesis , X-Ray Diffraction , Zinc Oxide/chemical synthesis
3.
Article in English | MEDLINE | ID: mdl-24556132

ABSTRACT

Eu(3+) co-doped ZnO/Zn2SiO4:Mn(2+) composites were synthesized via conventional solid state reaction route and were characterized by X-ray diffraction (XRD) scanning electron microscopy (SEM) and Fourier transform infra-red (FTIR) techniques. XRD studies reveal the presence of both ZnO and Zn2SiO4 phases. Photoluminescence properties of the samples were studied using 266 Nd-YAG laser excitations. Emission bands observed at ~400 nm are ascribed to ZnO phosphor. The green emission bands at 530 nm is associated with the presence of Mn(2+) ion, while orange (~583) and red (615 nm) bands are supposed to be due to the presence of Eu(3+) doped Zn2SiO4 phosphor. Energy transfer from power dependence of the sample for electric dipole transition (615 nm) was studied under 532 nm excitation by varying the power from 0.1 to 4.5 W. The estimated colour correlated temperature (CCT) values are found to be ~4875 and 4458 K under 266 nm and 532 nm laser (0.5 W) excitations. These values are close to those of tubular fluorescent or cool white/daylight compact fluorescent (CFL) (~5000 K) lamps. The present composite phosphor may have potential application in display devices.


Subject(s)
Europium/chemistry , Luminescence , Manganese/chemistry , Silicates/chemistry , Zinc Compounds/chemistry , Zinc Oxide/chemistry , Zinc/chemistry , Microscopy, Electron, Scanning , Spectroscopy, Fourier Transform Infrared , Temperature , X-Ray Diffraction
4.
J Neurol Neurosurg Psychiatry ; 80(7): 805-7, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19531689

ABSTRACT

BACKGROUND: Previous prevalence studies of Parkinson's disease (PD) in the UK have spanned a 40 year period and have predominantly been in the North of the country. These have presented rates by current age but have not examined this by age at disease onset. METHODS: A community based prevalence study was undertaken which attempted to identify all clinically diagnosed cases of PD from primary and secondary care for the city of Cardiff, Wales, UK. A meta-analysis of all past studies in the UK, including our own, was also undertaken. RESULTS: Overall, 380 cases of PD were identified from a population of 292 637 residents, giving a crude prevalence rate of 130 per 100 000 (95% CI 117 to 144) and an age standardised rate of 142 per 100 000 (95% CI 128 156), standardised to the 1997 England and Wales population. Our prevalence rates were very similar to the weighted average of previous UK studies although there was evidence of between study heterogeneity (p = 0.0006). 5.4% and 31.2% of prevalent PD patients had their disease onset below the age of 50 or 65 years, respectively. CONCLUSIONS: The data suggest that there are no major geographical variations in the prevalence of PD in the UK and that the age adjusted prevalence rate has remained relatively stable over the past 40 years. Although PD risk is far greater in older subjects, patients with young onset are not that uncommon in the community, and health and social care provision should reflect their needs.


Subject(s)
Parkinson Disease/epidemiology , Age of Onset , Cross-Sectional Studies , England/epidemiology , Female , Humans , Male , Parkinson Disease/diagnosis , Prevalence
6.
Br J Urol ; 74(5): 646-51, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7530129

ABSTRACT

OBJECTIVE: To study the effectiveness of radiation therapy (RT) for the primary tumour and for groin node and distant metastases in patients with squamous cell carcinoma of the penis. SUBJECTS AND METHODS: Between January 1959 and June 1988, 156 patients with negative lymph nodes in the groin underwent RT of the primary tumour. RT was also administered to 120 patients with lymph node involvement in the groin and to nine with distant metastases. RESULTS: Local control of the primary tumour was achieved in 65% of patients with RT alone and in another 33% with salvage surgery. Lymph node recurrence in the groin was seen in 11% of patients and the corrected 5-year disease-free survival was 87%. Pre-operative inguinal RT was useful in patients with mobile lymph nodes > or = 4 cm in size in the groin, with only 8% of such lymphadenectomy specimens showing perinodal infiltration and only 3% of such patients having post-operative groin recurrences. Pelvic and/or para-aortic RT was ineffective in patients with pelvic node metastases. Palliative RT resulted in amelioration of symptoms in 56% of patients with fixed lymph nodes in the groin, all five patients with painful bony metastases and one of two patients with cord compression and paraplegia. CONCLUSION: Radiation therapy is ideal for patients with T1 and T2 primary cancers of the penis. Pre-operative RT is useful for patients with mobile lymph nodes > or = 4 cm in size in the groin. RT provides effective palliation in patients with advanced regional disease and/or distant metastases.


Subject(s)
Carcinoma, Squamous Cell/radiotherapy , Penile Neoplasms/radiotherapy , Brachytherapy , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/surgery , Disease-Free Survival , Follow-Up Studies , Groin , Humans , Lymphatic Metastasis , Male , Neoplasm Recurrence, Local , Palliative Care , Penile Neoplasms/mortality , Penile Neoplasms/surgery , Prognosis , Retrospective Studies , Salvage Therapy , Survival Analysis , Treatment Outcome
10.
J Surg Oncol ; 28(2): 134-6, 1985 Feb.
Article in English | MEDLINE | ID: mdl-3968897

ABSTRACT

One thousand thirty-seven female breast cancers were treated at the Cancer Institute (WIA), Madras, between 1965 and 1978. Five hundred twenty-one of them (ie, just over 50%) were in stage III, with extensive local disease, unsuitable for surgery ab initio. Four hundred twelve of them (group A) received radiation therapy (RT) initially and 109 (group B) a combination of radiation and chemotherapy (CT). In 68% of the former and 77% of the latter the tumours became resectable after this preliminary treatment. Radical mastectomy in group A and Patey's mastectomy in group B were performed. The material in these two groups was similar. The five-year survival NED in group A was 45%, and in group B 64.61%. Adequate surgery following RT and CT seemed essential to improve survival. The impact of added chemotherapy (CT) was mainly felt in the node-positive cases.


Subject(s)
Breast Neoplasms/therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Castration , Cobalt Radioisotopes/therapeutic use , Combined Modality Therapy , Female , Humans , Mastectomy , Neoplasm Staging , Prognosis
11.
Acta Genet Med Gemellol (Roma) ; 24(1-2): 163-4, 1975.
Article in English | MEDLINE | ID: mdl-1224919

ABSTRACT

The study of middle phalangeal hair on a sample of some 5000 nonrelated subjects of both sexes and different age groups, representing 11 South Indian populations, has shown very limited sex and age variability. The frequencies fall within the general range of Indian population groups. Most of the groups tested show genetic homogeneity.


Subject(s)
Fingers , Hair , Skin/anatomy & histology , Adolescent , Adult , Aged , Child , Female , Genetics, Medical , Humans , India , Male , Middle Aged
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