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1.
J Ayurveda Integr Med ; 13(3): 100605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35868134

RESUMO

Fatty Liver, one of the most common liver diseases worldwide, usually emerges due to lipid accumulation, mostly triglycerides in hepatocytes. Fat exists in the liver naturally, but if it surpasses 5-10% of the liver's total weight, it can result in fatty liver. In this case, report effect of Ayurveda intervention in grade II fatty liver is reported. Thirty-five-year-old obese male with grade II fatty liver presented with fatigue, abdominal pain, heaviness, and incomplete bowel evacuation to the National Institute of Ayurveda hospital, Jaipur, Rajasthan, India. On examination, there was no significant clinical abnormality except a high body mass index (BMI = 30.2). Hematological examinations revealed altered Alanine transaminase, fasting blood glucose, total cholesterol, low-density lipoprotein, and triglycerides. The patient was diagnosed sonologically with a grade II fatty liver. The patient was given Ayurveda treatment for two months with three treatment regimens. The patient was assessed for improvement in signs and symptoms, hematological parameters, and quality of life using a chronic liver disease questionnaire (CLDQ). After two months, significant improvement was observed in signs and symptoms, BMI (24.7), and CLDQ. No fatty tissue was reported sonologically, and all altered biochemical parameters were within normal limits. Present case highlights the potential of Ayurveda interventions in managing non-alcoholic fatty liver disease and obesity.

2.
Water Sci Technol ; 84(10-11): 2760-2779, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34850692

RESUMO

This study aims to identify the water flux in an earth dam using heat flux due to convection. Sixteen earth dam models were constructed in a hydraulic flume by varying geometrical and flow input parameters to identify heat and water flux. Homogeneous as well as earth dams with clay cores were built in a hydraulic flume. Temperature measurements were done to calculate heat flux in the experimental model. A finite element model of the earth dam using Seep/w was developed to obtain water flux, while temp/w was used to obtain heat flux. These results were used as input in Temp/w and Seep/w in Geostudio 2020. Significant reduction of the heat and water flux was seen while comparing the homogeneous models with central impervious core models. An increase in the heat and water flux was observed on increasing the downstream filter's length, longitudinal slope, and vice versa with the upstream slope and the thickness of the clay core. Comparing fluxes in a homogeneous dam model (model 1) with the clay core model (model 9) with top width 2.4 m and bottom width 18 m in model 9, both water flux and heat flux were reduced by 78.46%. While comparing it with model 10, with bottom core width of 18 m and top core width of 1.9 m, both water flux and heat flux reduced by 77.72%. Heat flux measurements were found to be a valuable alternative to detecting water flux and seepage in an earth dam at a reduced cost.


Assuntos
Temperatura Alta , Água , Convecção , Modelos Teóricos , Movimentos da Água
3.
QJM ; 114(7): 455-463, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34347106

RESUMO

BACKGROUND: Corticosteroids have become the mainstay treatment in severe COVID-19. However, its role is mild disease is controversial due to lack of robust scientific evidence. This systematic review and meta-analysis were conducted to assess effect of steroids in mild COVID-19 patients. METHODS: PubMed, EMBASE, Web of Science and medRxiv were searched from 31 December 2019 to 14 May 2021 for studies that reported effectiveness of steroids in non-oxygen requiring COVID-19 patients in terms of progressing to severe disease, mortality, duration of fever, duration of viral clearance and length of hospital stay (LOHS). Studies on inhalational steroids, case reports and reviews were excluded. Risk of bias (ROB) was assessed by the Cochrane's ROB tool and ROBANS tool. Quantitative data synthesis was done using the generic inverse variance method. RESULTS: A total of 6411 studies were identified, 2990 articles were screened after exclusion. Seven studies which fit the criteria (involving 2214 non-oxygen requiring COVID-19 patients) were included and analysed. Overall odds of progression to severe disease among the non-oxygen requiring COVID-19 patients receiving steroids was 5.97 [95% confidence interval (CI): 1.27-27.99, I2 = 0%] and odds of death (OR: 1.35, 95% CI: 1.01-1.79; I2 = 0%) as compared to the patients not receiving steroids. Mean duration of fever (7.4 days), duration to viral clearance (18.9 days) and LOHS (20.8 days) were significantly higher in the steroid arm, as compared to that in no-steroid arm (6.7, 16.5 and 15.2 days, respectively). CONCLUSION: Steroids in non-oxygen requiring COVID-19 patients can be more detrimental than beneficial. PROTOCOL REGISTRATION: The study was prospectively registered in PROSPERO (CRD 42021254951).


Assuntos
COVID-19 , Corticosteroides/uso terapêutico , Humanos , Tempo de Internação , SARS-CoV-2 , Esteroides
4.
QJM ; 114(7): 464-470, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34254132

RESUMO

BACKGROUND: Mucormycosis (MM) is a deadly opportunistic fungal infection and a large surge in COVID-19-associated mucormycosis (CAM) is occurring in India. AIM: Our aim was to delineate the clinico-epidemiological profile and identify risk factors of CAM patients presenting to the Emergency Department (ED). DESIGN: This was a retrospective, single-centre, observational study. METHODS: We included patients who presented with clinical features or diagnosed MM and who were previously treated for COVID-19 in last 3 months of presentation (recent COVID-19) or currently being treated for COVID-19 (active COVID-19). Information regarding clinical features of CAM, possible risk factors, examination findings, diagnostic workup including imaging and treatment details were collected. RESULTS: Seventy CAM patients (median age: 44.5 years, 60% males) with active (75.7%) or recent COVID-19 (24.3%) who presented to the ED in between 6 May 2021 and 1 June 2021, were included. A median duration of 20 days (interquartile range: 13.5-25) was present between the onset of COVID-19 symptoms and the onset of CAM symptoms. Ninety-three percent patients had at least one risk factor. Most common risk factors were diabetes mellitus (70%) and steroid use for COVID-19 disease (70%). After clinical, microbiological and radiological workup, final diagnosis of rhino-orbital CAM was made in most patients (68.6%). Systemic antifungals were started in the ED and urgent surgical debridement was planned. CONCLUSION: COVID-19 infection along with its medical management have increased patient susceptibility to MM.


Assuntos
COVID-19 , Mucormicose , Adulto , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Mucormicose/diagnóstico , Mucormicose/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
5.
J Colloid Interface Sci ; 572: 198-206, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244080

RESUMO

In the present work, the three-dimensional ultra-fine platinum nanoflowers are directly deposited on carbon-coated gas diffusion layer electrode (C-GDL) by a single-step electrodeposition method towards the application of polymer electrolyte fuel cells. The surface morphology, particle size distribution, crystallinity, and chemical oxidation state of platinum nanoflowers are examined using various techniques. The morphological features of the Pt nanostructures are highly influenced by the difference in current density. Notabely, the Pt nanospheres converts into three-dimensional nanoflower with an increase in current density from -1.6 to -32 mA cm-2. Electrodeposited Pt catalyst on C-GDL as the cathode catalyst was fabricated and steady-state polarization studies were carried out. Mainly, the fuel cell performance is analysed considering the electrodeposited Pt morphology. Among the prepared electrocatalysts, the nanoflower shaped Pt catalyst exhibit a high peak power density of 660 mW cm-2 at 0.6 V in PEFC.

6.
Water Sci Technol ; 79(3): 458-465, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30924800

RESUMO

The goal of this study was to investigate what kind of impact the removal of particulate organic matter with 33µm rotating belt filter (RBF) (as a primary treatment) will have on the membrane bioreactor (MBR) performance. Two small MBR pilot plants were operated in parallel, where one train treated 2mm screened municipal wastewater (Train A) and the other train treated wastewater that had passed through a RBF with a 33µm filter cloth (Train B). The RBF was operated without a filter mat on the belt. About one third of the organic matter was removed by the fine mesh filter. The assessment of the overall performance showed that the two pilot plants achieved approximately the same removal efficiencies with regard to total suspended solids (TSS), chemical oxygen demand (COD), total phosphorus and total nitrogen. It was also observed that the system with 33µm RBF as a primary treatment produced more sludge, which could be used for biogas production, and required about 30% less aeration downstream. Transmembrane pressure was significantly lower for the train receiving 33µm primary treated wastewater compared to the control receiving 2mm screened wastewater.


Assuntos
Reatores Biológicos , Membranas Artificiais , Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/análise , Desnitrificação , Águas Residuárias
7.
Nanoscale Adv ; 1(12): 4926-4937, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36133132

RESUMO

Herein, fluorine enrichment in mesoporous carbon (F-MC) was explored to introduce maximum charge polarization in the porous matrix, which is beneficial for the preferential orientation of O2 molecules and their subsequent reduction. Ex situ doping of F to porous carbon derived from phloroglucinol-formaldehyde resin using Pluronic F-127 as a structure-directing agent is standardized. The optimized F-MC catalyst exhibited excellent electrocatalytic activity towards the oxygen reduction reaction (ORR) in alkaline media (0.1 M KOH) with an onset potential of -0.10 V vs. SCE and diffusion-limiting current of 4.87 mA cm-2, while displaying only about 50 mV overpotential in the half-wave region compared to Pt-C (40 wt%). In the stability test, the catalyst showed only 10 mV negative shift in its half-wave potential after 10 000 potential cycles. The rotating ring disk electrode (RRDE) experiments revealed that F-MC follows the most preferable 4e - pathway (n = 3.61) with a moderate peroxide (HO2 -) yield. This was further supported by density functional theory calculations and also deeply explains the existence of defects being beneficial for the ORR. The F-MC catalyst owing to its promising ORR activity and long-term electrochemical stability can be viewed as a potential alternative ORR catalyst for anion exchange membrane fuel cell applications.

8.
R Soc Open Sci ; 4(9): 170368, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28989744

RESUMO

Mixed-matrix membranes (MMMs) were developed by impregnating organofunctionalized nanoadditives within fouling-susceptible polysulfone matrix following the non-solvent induced phase separation (NIPS) method. The facile functionalization of nanoparticles of anatase TiO2 (nano-TiO2) by using two different organoligands, viz. Tiron and chromotropic acid, was carried out to obtain organofunctionalized nanoadditives, FT-nano-TiO2 and FC-nano-TiO2, respectively. The structural features of nanoadditives were evaluated by X-ray diffraction, X-ray photoelectron spectroscopy, Raman and Fourier transform infrared spectroscopy, which established that Tiron leads to the blending of chelating and bridging bidentate geometries for FT-nano-TiO2, whereas chromotropic acid produces bridging bidentate as well as monodentate geometries for FC-nano-TiO2. The surface chemistry of the studied membranes, polysulfone (Psf): FT-nano-TiO2 UF and Psf: FC-nano-TiO2 UF, was profoundly influenced by the benign distributions of the nanoadditives enriched with distinctly charged sites ([Formula: see text]), as evidenced by superior morphology, improved topography, enhanced surface hydrophilicity and altered electrokinetic features. The membranes exhibited enhanced solvent throughputs, viz. 3500-4000 and 3400-4300 LMD at 1 bar of transmembrane pressure, without significant compromise in their rejection attributes. The flux recovery ratios and fouling resistive behaviours of MMMs towards bovine serum albumin indicated that the nanoadditives could impart stable and appreciable antifouling activity, potentially aiding in a sustainable ultrafiltration performance.

9.
Water Sci Technol ; 75(11-12): 2598-2606, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28617279

RESUMO

Fine mesh rotating belt sieves (RBS) offer a very compact solution for removal of particles from wastewater. This paper shows examples from pilot-scale testing of primary treatment, chemically enhanced primary treatment (CEPT) and secondary solids separation of biofilm solids from moving bed biofilm reactors (MBBRs). Primary treatment using a 350 microns belt showed more than 40% removal of total suspended solids (TSS) and 30% removal of chemical oxygen demand (COD) at sieve rates as high as 160 m³/m²-h. Maximum sieve rate tested was 288 m³/m²-h and maximum particle load was 80 kg TSS/m²-h. When the filter mat on the belt increased from 10 to 55 g TSS/m², the removal efficiency for TSS increased from about 35 to 60%. CEPT is a simple and effective way of increasing the removal efficiency of RBS. Adding about 1 mg/L of cationic polymer and about 2 min of flocculation time, the removal of TSS typically increased from 40-50% without polymer to 60-70% with polymer. Using coagulation and flocculation ahead of the RBS, separation of biofilm solids was successful. Removal efficiencies of 90% TSS, 83% total P and 84% total COD were achieved with a 90 microns belt at a sieve rate of 41 m³/m²-h.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Biofilmes , Análise da Demanda Biológica de Oxigênio , Noruega , Projetos Piloto , Eliminação de Resíduos Líquidos/instrumentação
10.
Luminescence ; 32(2): 159-170, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27323703

RESUMO

This article reports on the luminescence properties of rare earth (Dy3+ and Tm3+ )ions doped SrGa2 Si2 O8 phosphor were studied. SrGa2 Si2 O8 phosphors weresynthesizedby employing solid state reaction method.From the measured X-ray diffraction (XRD) pattern of the samplemonoclinic phase structure has been observed. Thermoluminescenceand Mechanoluminescence properties of the γ-ray irradiated samples have been studied. Photoluminescence spectra of Dy3+ activated SrGa2 Si2 O8 phosphor has been measured with an excitation wavelength at 348 nm,and it shows two emission bands at 483 and 574 nm due to 4 F9/2  â†’ 6 H15/2 and 4 F9/2  â†’ 6 H13/2 transitions respectively. Whereas the photoluminescence spectra of Tm3+ activated SrGa2 Si2 O8 phosphor has been measured with an excitation wavelength at 359 nm and it exhibits two emission bands at 454 and 472 nm due to 1 D2  â†’ 3 F4 and1 G4  â†’ 3 H6 transitions respectively. In thermoluminescence study, γ-irradiatedthermoluminescence glow curve of SrGa2 Si2 O8 :Dy3+ phosphor shows two well defined peaks at 293 °C (peak1)and 170 °C (peak2) whereas thermoluminescence glow curve of SrGa2 Si2 O8 :Tm3+ phosphor shows peaks at 292 °C (peak1) and 184 °C (peak2) indicating that two sets of traps are being activated within the particular temperature range and the trapping parameters associated with the prominent glow peaks of SrGa2 Si2 O8 :Dy3+ and SrGa2 Si2 O8 :Tm3+ are calculated using Chen's peak shape and initial rise method.From the Mechanoluminescence study, only one glow peak has been observed. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Disprósio/análise , Gálio/análise , Luminescência , Oxigênio/análise , Estrôncio/análise , Túlio/análise
11.
J Fluoresc ; 27(1): 251-261, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27815786

RESUMO

LaBO3:xDy3+ (x = 0.05 mol%, 0.1 mol%, 0.2 mol%, 0.5 mol%, 1 mol% and 2 mol%) phosphors were synthesized by solid-state reaction method. X-ray diffraction technique was used to confirm the formation of compound. Photoluminescence emission spectra shows two emission peaks at 470 nm and 575 nm when excitation wavelength is set at 352 nm. Photoluminescence intensity increases upto 1 mol % of Dy3+ and then starts decreasing. Dipole-dipole interaction is found to be responsible for concentration quenching of photoluminescence intensity. Commission Internationale de I'Eclairage (CIE) chromaticity diagram demonstrates that the phosphor emits in bluish white region of the visible spectrum. Critical energy transfer distance between dopant ions was determined. The mechanoluminescence characteristics were studied by the impact method. The peaks of both the mechanoluminescence (ML) intensity and the total ML intensity of the UV exposed phosphors increases with increasing impact velocity for 1 mol % concentration of Dy3+. The ML sensitivity of the LaBO3:Dy3+ (Dy3+ = 1 mol %) phosphor is comparable with the reported ML of various inorganic phosphors. The thermoluminescence characteristics of the samples were also investigated. Thermoluminescence glow peaks were recorded with 480 Gy, 80 Gy and 20 Gy dose of γ-irradiation from Co60 Source. TL trapping parameters were determined by Chen's peak shape method and glow curve deconvolution method. LaBO3:Dy3+ phosphors were found to be good mechanoluminescent materials and can be used in stress sensing application.

12.
Nanoscale ; 8(30): 14650-64, 2016 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-27439022

RESUMO

Nitrogen and fluorine co-doped graphite nanofibers (N/F-GNF) and their cumulative effect with Fe and Co have been developed as an alternative non-precious metal catalyst for efficient oxygen reduction reaction (ORR) in acidic media. The synergistic effect between the doped hetero atoms and the co-ordinated Fe and Co towards ORR activity and durability of the catalyst is deeply investigated. A high ORR onset potential comparable with commercial Pt/C catalyst is observed with the Fe-Co/NF-GNF catalyst, which indicates that this catalyst is a potential alternative to Pt/C. A fivefold increase in mass activity is achieved by the Fe-Co/NF-GNF catalyst compared to the simple N/F-GNF catalyst, which endorses the significant role of transition metal atoms in enhancing ORR activity. The advanced Fe-Co/NF-GNF catalyst also exhibits complete tolerance to CH3OH and CO. The Fe-Co/NF-GNF catalyst also exhibits excellent durability towards the ORR with only a 10 mV negative shift in its half wave potential after a 10 000 repeated potential cycling test, whereas in the case of a commercial Pt/C catalyst there was an ∼110 mV negative shift under similar environmental conditions. More stringent corrosive test cycles were also performed by maintaining the cell as high as 1.4 V with a later decrease to 0.6 V vs. RHE for 300 cycles, which showed the excellent durability of the Fe-Co/NF-GNF catalyst in comparison with the Pt/C catalyst. XPS analysis of the Fe-Co/NF-GNF catalyst presents the ORR active chemical states of N (pyridinic-N and graphitic-N) and F (semi-ionic-F) and the co-ordinated sites of Fe and Co species with the dopants. The excellent performance and durability of the Fe-Co/NF-GNF catalyst is due to the synergistic effect between the hetero atoms dopants (N and F) and strong co-ordinating bonds of M-N-C, which protect the graphene layers around the metallic species and greatly mitigates the leaching of Co and Fe during the long term cycling test. The high activity and long term durability of the Fe-Co/NF-GNF catalyst make it a promising ORR electrocatalyst for the fuel cell cathode reaction.

13.
Water Sci Technol ; 73(2): 337-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26819389

RESUMO

The purpose of this project was to investigate the effect of selective particle removal during primary treatment on nitrogen removal in moving bed biofilm reactors (MBBRs). Two small MBBR pilot plants were operated in parallel, where one train treated 2 mm screened municipal wastewater and the other train treated wastewater that had passed through a Salsnes Filter SF1000 rotating belt sieve (RBS) with a 33 µs sieve cloth. The SF1000 was operated without a filter mat on the belt. The tests confirmed that, for the wastewater characteristics at the test plant, Salsnes Filter primary treatment with a 33 µs RBS and no filter mat produced a primary effluent that was close to optimum. Removal of organic matter with the 33 µs sieve had no negative effect on the denitrification process. Nitrification rates improved by 10-15% in the train with 33 µs RBS primary treatment. Mass balance calculations showed that without RBS primary treatment, the oxygen demand in the biological system was 36% higher. Other studies have shown that the sludge produced by RBS primary treatment is beneficial for biogas production and will also significantly improve sludge dewatering of the combined primary and biological sludge.


Assuntos
Reatores Biológicos , Filtração , Nitrogênio/isolamento & purificação , Purificação da Água/métodos , Biofilmes , Desnitrificação , Nitrificação , Esgotos , Águas Residuárias
14.
Ann R Coll Surg Engl ; 97(5): 364-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26264088

RESUMO

INTRODUCTION: Postoperative pain after breast surgery is one of the major factors contributing to delay in mobilisation and prolonged hospital stay. A retrospective analysis was performed of patients undergoing skin sparing mastectomy and insertion of a subpectoral implant. The aim was to determine whether the use of an elastomeric local anaesthetic pump improved pain control and length of stay. METHODS: Twenty-five consecutive patients undergoing the above procedure were sited with an elastomeric local anaesthetic infusion pump intraoperatively, in addition to standard regular and pro re nata analgesia. The control group comprised 25 patients undergoing the same procedure in the same year who received standard analgesia alone. Visual analogue scale scores were recorded for the duration of inpatient stay, as was any further analgesic requirement. RESULTS: The median age was 51 years (range: 26-75 years) in the intervention group and 50 years (range: 28-70 years) in the control group. The mean visual analogue scale score was 0.28 (standard deviation [SD]: 0.61) at 24 hours for the intervention group and 1.84 (SD: 0.37) for the control group (p<0.0001). The mean length of stay was 1.8 days (SD: 0.71 days) for the intervention group and 2.28 days (SD: 0.94 days) for the control group (p=0.15). There were no complications involving catheter placement, leakage or toxicity relating to use of the local anaesthetic. CONCLUSIONS: There was significantly reduced pain with the use of the local anaesthetic infusion pump. The elastomeric pump is a step towards enhanced patient recovery after breast surgery in the case of skin sparing mastectomy and subpectoral tissue expander reconstruction.


Assuntos
Mama/cirurgia , Mamoplastia/métodos , Mastectomia/efeitos adversos , Dor Pós-Operatória/terapia , Dispositivos para Expansão de Tecidos , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Estudos Retrospectivos
15.
Rev Sci Instrum ; 85(11): 113504, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430113

RESUMO

The neutral beam injector of steady state superconducting tokamak (SST1-NBI) at IPR is designed for injecting upto 1.7 MW of neutral beam (Hº, 30-55 keV) power to the tokamak plasma for heating and current drive. Operations of the positive ion source (PINI or Plug-In-Neutral-Injector) of SST1-NBI were carried out on the NBI test stand. The PINI was operated at reduced gas feed rate of 2-3 Torr l/s, without using the high speed cryo pumps. Experiments were conducted to achieve a stable beam extraction by optimizing operational parameters namely, the arc current (120-300 A), acceleration voltage (16-40 kV), and a suitable control sequence. The beam divergence, power density profiles, and species fractions (H(+):H2(+):H3(+)) were measured by using the diagnostics such as thermal calorimetry, infrared thermography, and Doppler shift spectroscopy. The maximum extracted beam current was about 18 A. A further increase of beam current was found to be limited by the amount of gas feed rate to the ion source.

17.
Water Sci Technol ; 69(9): 1942-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24804671

RESUMO

The purpose of this project was to investigate the effect of selective particle removal during primary treatment on downstream biological nutrient removal processes. Bench-scale Salsnes Filter fine mesh sieves were used as a primary treatment to obtain different organic fractions to test the effect on denitrification. Activated sludge and moving bed biofilm reactor anoxic tests were performed on municipal wastewater collected from two full-scale wastewater treatment plants located around the Oslo region (Norway). About 43% of the suspended solids in the wastewater was less than 18 µm, and 14% was between 18 and 150 µm. The effect of particulate chemical oxygen demand (COD) removal on denitrification rates was very minor.


Assuntos
Filtração/instrumentação , Nitrogênio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Biomassa , Desnitrificação , Filtração/métodos , Temperatura
18.
Luminescence ; 29(8): 1082-94, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24760580

RESUMO

Li3 PO4 phosphors prepared by solid-state diffusion technique and lyoluminescence (LL) as well as mechanoluminescence (ML) studies are reported. Dy- and Tb-activated phosphors show dosimetric characteristics using LL and ML techniques. The energy levels and hence trapping and detrapping of charge carriers in the material can be studied using ML. Li3 PO4 phosphor can be used in the dosimetric applications for ionizing radiation. By using the LL technique, the LL characteristics of Li3 PO4 may be useful for high radiation doses. We also report a more detailed theoretical understanding of the mechanism of LL and ML.


Assuntos
Disprósio/química , Luminescência , Modelos Teóricos , Térbio/química , Cristalização , Difusão , Relação Dose-Resposta à Radiação , Raios gama , Compostos de Lítio/química , Medições Luminescentes/métodos , Solventes/química , Dosimetria Termoluminescente
19.
Luminescence ; 29(1): 58-64, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23554212

RESUMO

Li3 PO4 phosphor was prepared using a modified solid-state diffusion technique. In this work, photoluminescence, lyoluminescence and mechanoluminescence studies were carried out in a Li3 PO4 microcrystalline powder doped with different rare earths. In photoluminescence studies, characteristic emission of Ce and Eu was observed. The lyoluminescence glow curves of Li3 PO4 microcrystals show that lyoluminescence intensity initially increases with time and then decreases exponentially. The decay time consists of two components for all masses. The dependence of decay time, especially the longer component, on mass has been investigated. Experiments on γ-irradiated crystals have proved that the light emission originates from the recombination of released F-centres with trapped holes (V2-centres) at the sulfuric acid-solid interface. Incorporation of bivalent alkali in solid lithium phosphate leads to an enhancement of lyoluminescence. A possible explanation for the experimental results has been attempted. The phosphor has a mechanoluminescence single glow peak. Mechanoluminescence intensity under various loading conditions was investigated. It is observed that mechanoluminescence intensity increases with increasing impurity concentration and increasing piston impact velocity. The results may be considered as only being of academic interest in solid-state materials.


Assuntos
Cério/química , Európio/química , Compostos de Lítio/química , Luminescência , Fosfatos/química
20.
Surgeon ; 9(5): 255-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21843819

RESUMO

BACKGROUND: Gynaecomastia is the most common benign condition of the male breast and accounts for up to 80% of male breast referrals. We sought to identify any changes in the number of patients referred with the condition and assess its impact on clinical practice. METHODS: Patients were identified from two prospectively maintained databases. Diagnosis of gynaecomastia was based on clinical findings, ultrasound scan (USS) assessment and/or histology. RESULTS: There was a significant increase in the number of men referred to a specialist unit and diagnosed with gynaecomastia. Gynaecomastia was more prevalent in the under twenties age group. Core biopsy (CB) became the histological investigation of choice for men with unilateral disease and there was no change in the percentage of men undergoing surgery. CONCLUSION: Most men are looking for reassurance that their condition is benign and that no intervention is required. Thus it is important to offer these men psychological support as part of their treatment.


Assuntos
Ginecomastia/epidemiologia , Encaminhamento e Consulta/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Ginecomastia/psicologia , Ginecomastia/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta/tendências , Adulto Jovem
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