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1.
Cureus ; 15(10): e48035, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38034210

RESUMO

Introduction The under-five age group is crucial because the health profile of this age group will have a huge effect on the future development of the nation. Early infancy is marked by several distinct developmental characteristics. Progress in each domain of childhood development is used to track a child's development. Objectives The objectives of the present study were to assess and compare the growth of under-five children of employed and unemployed mothers in the Etawah District of Uttar Pradesh, India. Material and methods A community-based cross-sectional survey was carried out in Etawah district's urban and rural areas between January 2021 and June 2022. A total of 200 mothers with children under the age of five were recruited using the purposive sampling method. To gather pertinent information, a semi-structured, pre-tested, interviewer-administered questionnaire was used. Results In the present study on the comparison of the growth of children among employed and unemployed mothers, it shows that 48 children (50.5%) with a weight between 10.5 and 15 kg were of employed mothers, while 52 children weighing less than 10.5kg were of unemployed mothers (p<0.001). Forty-four children (57.1%) with a chest circumference of more than 48 cm were of employed mothers, while 26 children (78.8%) with a chest circumference of less than 45 cm were of unemployed mothers (p = 0.001). Conclusion The present study indicates that statistically significant differences were found in age-appropriate gain in weight and chest circumference, which was higher among the children of employed mothers in comparison to children of unemployed mothers. There was no statistically significant difference in age-appropriate gain in height, head circumference, or mid-upper arm circumference among the children of employed mothers and unemployed mothers.

2.
RSC Adv ; 13(29): 20164-20178, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37416910

RESUMO

The Eu3+ doped and Mg2+/Ca2+ co-doped ZnGa2O4 phosphor samples were synthesized by solid-state reaction method and their structural and optical properties studied. The phase, crystallinity and particles size of the phosphor samples were studied by XRD and SEM measurements. EDS analyses were used to identify the elements present in the phosphor materials. The vibrational groups present in the phosphor samples were examined by Fourier transform infrared (FTIR) measurements. Pure ZnGa2O4 emits intense blue light under 260 nm excitation. However, Eu3+ doped and Mg2+/Ca2+ co-doped ZnGa2O4 phosphor samples exhibit intense red emission under 393 nm excitation. A bluish white color is observed in these samples under 290 nm excitation. The maximum PL emission intensity is found at 0.1 mol% Eu3+ doping concentration. For higher concentrations, concentration quenching was observed due to dipole-dipole interaction. The emission intensity is enhanced upto 1.20 and 2.91 times on co-doping of Mg2+ and Ca2+via induced crystal field due to charge imbalance. The emission intensity of the phosphor is found to enhance further on annealing the samples at 873 K. Under various excitation wavelengths, color tunability was seen from blue to bluish-white to red regions. The lifetime of the 5D0 level of the Eu3+ ion improves via doping of Mg2+/Ca2+ ions and it increases appreciably on annealing. The temperature dependent photoluminescence study (TDPL) reveals a thermal quenching behavior of the sample with thermal stability ∼65% and activation energy ∼0.223 eV in the Eu3+/Ca2+ co-doped ZnGa2O4 phosphor sample.

3.
RSC Adv ; 13(6): 3592-3601, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36756577

RESUMO

The Ho3+-doped YVO4 phosphors were successfully prepared via a sol-gel process in which citric acid was used as a chelating agent. X-ray diffraction (XRD) confirmed the effective inclusion of Ho3+ ions into the host matrix with the formation of single phase YVO4. The surface morphology was observed using SEM, the results of which showed a grain growth propensity and the agglomeration of prepared phosphors. The V-O (VO4 3-) vibration mode was analyzed through Fourier transform infrared (FTIR) spectra. The spectroscopic properties were reported through UV-vis-NIR diffuse reflectance and photoluminescence (PL) spectra. The Judd-Ofelt (J-O) intensity parameters Ω 2 = 0.03 × 10-20 cm2, Ω 4 = 0.22 × 10-20 cm2, and Ω 6 = 0.23 × 10-20 cm2 obtained for the Y0.97VO4:0.03Ho3+ phosphors were used to obtain the total transition probabilities (A T), radiative lifetimes (τ rad) and branching ratios (ß) for the certain transitions of Ho3+ ions. Under 310 nm UV excitation, the visible emission spectra were measured, and an intense emission was observed around 541 nm (green region) for all the samples. The emission cross-section σ P(λ) was 3.22 × 10-21 cm2 and the branching ratio (ß) was 0.816; these were investigated to capture the optimal concentration of the Y0.97VO4:0.03Ho3+ phosphor. The estimated color coordinates were observed in the green region of CIE diagram. Ultimately, the superior properties (σ P(λ), ß, and color purity) of Y0.97VO4:0.03Ho3+ phosphor may make it suitable for green emitting devices.

4.
J Obstet Gynaecol ; 42(7): 2588-2591, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35983664

RESUMO

Stromal cells possess unique properties to regenerate themselves and cure various chronic illnesses. An easily available and ethical source for procurement of stromal cells is umbilical cord blood which is now being stored for future use. Vedic texts also describe the cord blood as a source of life. However, Indian traditions seem to preserve one more alternative for storage and procurement of stromal cells. Traditionally, in many parts of India, the umbilical cord stump is dried and stored for future use. It is used as a medicine for some illness and to treat infertility. Since Indian traditions are an excerpt of Vedic science, it points towards the possible emergence of dried stump as an easy and cost-effective means for stromal cell procurement and storage. The present review compiles the literature available on these traditional practices and stresses upon the need of rigorous experimental and theoretical research in the area.


Assuntos
Células Estromais , Cordão Umbilical , Humanos , Índia
5.
J Vector Borne Dis ; 58(3): 219-227, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35170459

RESUMO

BACKGROUND & OBJECTIVES: Universal coverage of population with long-lasting insecticidal nets (LLINs) living in endemic areas inhabited by ethnic tribal communities or in difficult to reach areas was found effective for disease control where other interventions such as indoor residual spraying have limited success because of operational issues. Evaluation of different LLINs with varied insecticides and fabrics are being evaluated to meet the demand of new products. This study was undertaken on two brands of LLINs, DuraNet© and Interceptor® that varied in fabric and manufacturing technologies to assess the usability in field conditions for atleast three years. METHODS: In large-scale field trials DuraNet©, alpha cypermethrin incorporated polyethylene net, was evaluated in Odisha state while, Interceptor® net, alpha cypermethrin coated polyester net was evaluated in Chhattisgarh and Gujarat states for a period of three years following WHO guidelines. Durability, usage pattern and washing behavior were monitored through periodic surveys and physical examination of nets. RESULTS: Survivorship of both the nets was 84-100% and every night usage rate was >62% in all seasons. Washing frequency was largely within the prescribed limits. The proportion of DuraNet© with holes was 26.7% in year one 74% in year three. In Gujarat, proportion of Interceptor® nets with holes at six months was 33.3% increased to 87% in year three and in Chhattisgarh, 6.7% after six months to 93.3% after three years of use respectively. INTERPRETATION & CONCLUSION: Both the nets revealed a useful life of three years under the field condition.


Assuntos
Mosquiteiros Tratados com Inseticida , Inseticidas , Malária , Humanos , Índia , Inseticidas/farmacologia , Macrolídeos , Malária/prevenção & controle , Controle de Mosquitos
6.
J Assoc Physicians India ; 67(4): 29-32, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31309792

RESUMO

BACKGROUND: Hyperhomocystienemia is a plausible common link between psoriasis and associated co-morbidities. AIM: To assess and compare serum homocystiene levels in 160(M:F 94:66) patients aged 18-70 years with chronic plaque psoriasis of varying severity with or without metabolic syndrome, cardiovascular and thyroid disorders and controls. The 155 controls (M:F 97:58) were healthy volunteers aged between 18 and 66 years. RESULTS: Overall, 123 (76.9%) psoriasis patients with or without co-morbidities and 87 (56.1%) controls had elevated serum homocystiene levels; 23.48±14.37 and 18.74±12.59 (mean±SD) µmol/L, respectively. Eighty-one (58%) patients had associated co-morbidities with mean serum homocystiene levels of 22.65±13.70 µmol/L.The difference between psoriasis patients with or without comorbidities and controls was statistically significant. CONCLUSIONS: Hyperhomocystienemia in psoriasis patients with or without comorbidities versus healthy controls suggests its possible dysregulation in psoriasis. The significance of hyperhomocystienemia as an independent risk factor for cardiovascular or other comorbidities in psoriasis patients remains tenuous at best. Well-designed studies will perhaps resolve this issue.


Assuntos
Hiper-Homocisteinemia/epidemiologia , Psoríase/complicações , Psoríase/epidemiologia , Adolescente , Adulto , Idoso , Doenças Cardiovasculares , Comorbidade , Humanos , Síndrome Metabólica , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
8.
J Assoc Physicians India ; 66(1): 14-8, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-30341839

RESUMO

Background: Association between hyperuricemia and hypertension has been recognized for many years. Whether hyperuricemia is the cause or the effect is debatable. Materials and methods: This case control study was conducted to assess serum uric acid (SUA) levels in fifty newly diagnosed essential hypertensive patients and fifty normotensive controls which were matched for age and sex. Detailed anthropometric characteristics including height, weight, body mass index and waist hip ratio were measured. Hypertension was classified according to Joint National Committee (JNC) 7 criteria. Hyperuricemia was defined as SUA level of 6.8mg/dl or more in both men and women. SUA was measured by uricase method. Before collecting the blood samples, patients were advised to proceed on overnight fast of minimum eight hrs. Student's t­test for mean of continuous variables and Chi­square test for proportions were used for statistical significance. Results: Present study included 50 newly diagnosed cases of essential hypertension and 50 age and sex matched normotensive healthy volunteer. Prevalence of hyperuricemia was 24% among the cases and 6% among the controls (P < 0 .05). Odds ratio was 4.9 (Cl=1.3 to 18.8). The mean SUA was significantly higher in the cases (5.5±1.7 mg/dl) than in the controls (4.9±1.1 mg/dl; P< 0.05). Odds ratio in male hyperuricemic hypertensive versus hyperuricemic normotensive was 6(CI=1.0 to 33.2) and 4.46(CI=0.4 to 42.5) among female hyperuricemic hypertensive versus hyperuricemic normotensives. Conclusion: Strong positive association was observed between hypertension and hyperuricemia in both male and female patients in this study.


Assuntos
Hipertensão Essencial/epidemiologia , Hiperuricemia/epidemiologia , Estudos de Casos e Controles , Hipertensão Essencial/diagnóstico , Feminino , Humanos , Hiperuricemia/diagnóstico , Índia/epidemiologia , Masculino , Fatores Sexuais , Ácido Úrico/sangue
9.
RSC Adv ; 8(60): 34699-34711, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35548605

RESUMO

The upconversion-based optical heating and temperature sensing characteristics are investigated in the Er3+/Yb3+/Bi3+ tri-doped La2O3 nano-phosphor synthesized through a solution combustion method. The structural measurements reveal an increase in lattice parameters and particles size of the phosphor on increasing the concentrations of Bi3+ ions. The energy dispersive spectroscopic (EDS) measurements confirm the presence of La, Er, Yb, Bi and O elements in the tri-doped phosphor. The absorption spectra show the large number of bands due to Er3+, Yb3+ and Bi3+ ions. The Er3+/Yb3+ co-doped phosphor gives strong green emission bands at 523 and 548 nm upon 976 nm excitation due to 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions of Er3+ ion, respectively. The emission intensity of these bands is enhanced upto 15 times in the presence of Bi3+ ions. The emission intensities of the 523 and 548 nm bands vary non-linearly with the pump power. The fluorescence intensity ratio (FIR) of the thermally coupled 523 and 548 nm emission bands shows efficient optical heating in the tri-doped phosphor. The FIR of the 523 and 548 nm emission bands further varies with the increase in temperature of the phosphor. The relative temperature sensing sensitivity has been calculated to be 71 × 10-4 K-1 at 450 K for the tri-doped phosphor. Thus, the Er3+/Yb3+/Bi3+ tri-doped La2O3 nano-phosphor may provide a platform to use it in the photonic devices, as an optical heater and temperature sensor.

10.
J Helminthol ; 91(5): 539-548, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27667321

RESUMO

Epidemiological and experimental evidence has supported the concept of using helminths as alternative bio-therapeutic agents in the treatment of type 1 diabetes (T1D). In the current study, two filarial proteins, recombinant Wuchereria bancrofti L2 (rWbL2) and Brugia malayi abundant larval transcript 2 (rBmALT-2) have been investigated, individually and in combination, for their therapeutic potential in streptozotocin (STZ)-induced T1D. The rWbL2 and rBmALT-2 proteins, when administered individually or in combination, have resulted in lowering of the blood glucose levels and reducing the incidence of T1D in mice. In addition, these proteins have led to reduced lymphocytic infiltration and decreased islet damage and inflammation. The curative effect was found to be associated with the suppression of release of tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), and increased production of interleukin (IL)-4, IL-5 and IL-10 cytokines by the splenocytes of the diabetic mice. Insulin-specific IgG1 and antigen-specific IgE antibodies were found to be elevated in the sera of mice treated with rWbL2 and rBmALT-2 proteins. From the findings in this study, it can be envisaged that both of these filarial immunomodulatory proteins have the potential to ameliorate T1D by altering the regulatory immune responses.


Assuntos
Brugia Malayi/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Proteínas de Helminto/administração & dosagem , Fatores Imunológicos/administração & dosagem , Wuchereria bancrofti/química , Animais , Autoanticorpos/sangue , Proteínas de Helminto/isolamento & purificação , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Fatores Imunológicos/isolamento & purificação , Ilhotas Pancreáticas/patologia , Camundongos , Resultado do Tratamento
11.
Hum Exp Toxicol ; 36(3): 276-286, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27164925

RESUMO

Modulation of myometrial spontaneity by cadmium (Cd) and its regulatory pathways was studied in rat uterus in the absence and presence of blockers of different signaling pathways. Isometric tension in myometrial strips, under a resting tension of 1 g, mounted in organ bath containing Ringer-Locke solution (RLS) continuously aerated with carbogen, was measured using data acquisition system-based physiograph and Lab Chart Pro V7.3.7 software. Mean integral tension was measured for 8 min. Cd (1 nM-0.1 mM) not only produced concentration-dependent inhibitory effect on rat myometrium but it (10 µM) also significantly ( p < 0.05) inhibited calcium chloride and BAY K-8644-induced myometrial contraction. Glybenclamide (10 µM), 4-aminopyridine (1 mM), and propranolol (10 µM) failed to significantly attenuate Cd-induced inhibitory responses, while L-NAME (0.1 mM), 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 25 µM), and 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ 22536; 1 µM) significantly ( p < 0.05) produced inhibitory effects on Cd-induced myometrial relaxation. Phenylephrine (1 nM-10 µM) and salbutamol (0.01 nM-0.1 µM)-induced relaxant effects on rat myometrium were significantly potentiated by 10 µM Cd. Thus based on the results of present functional study, it may be inferred that inhibitory effects of Cd on rat myometrium are mediated through blockade of L-type calcium channels and activation of NOS-NO-sGC and/or AC-cAMP pathways.


Assuntos
Cádmio/toxicidade , Canais de Cálcio Tipo L/fisiologia , GMP Cíclico/metabolismo , Miométrio/efeitos dos fármacos , 4-Aminopiridina/farmacologia , Animais , Feminino , Glibureto/farmacologia , Técnicas In Vitro , Relaxamento Muscular/efeitos dos fármacos , Miométrio/metabolismo , Miométrio/fisiologia , Fenilefrina/farmacologia , Propranolol/farmacologia , Ratos , Ratos Wistar
12.
Parasite Immunol ; 37(12): 624-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26434489

RESUMO

Understanding the modulation of the host-immune system by pathogens-like filarial parasites offers an alternate approach to prevent autoimmune diseases. In this study, we have shown that treatment with filarial proteins prior to or after the clinical onset of streptozotocin-induced type-1 diabetes (T1D) can ameliorate the severity of disease in BALB/c mice. Pre-treatment with Brugia malayi adult soluble (Bm A S) or microfilarial excretory-secretory (Bm mf ES) or microfilarial soluble (Bm mf S) antigens followed by induction of diabetes led to lowering of fasting blood glucose levels with as many as 57.5-62.5% of mice remaining nondiabetic. These proteins were more effective when they were used to treat the mice with established T1D as 62.5-71.5% of the mice turned to be nondiabetic. Histopathological examination of pancreas of treated mice showed minor inflammatory changes in pancreatic islet cell architecture. The therapeutic effect was found to be associated with the decreased production of cytokines TNF-α & IFN-γ and increased production of IL-10 in the culture supernatants of splenocytes of treated mice. A switch in the production of anti-insulin antibodies from IgG2a to IgG1 isotype was also seen. Together these results provide a proof towards utilizing the filarial derived proteins as novel anti-diabetic therapeutics.


Assuntos
Brugia Malayi/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Proteínas de Helminto/uso terapêutico , Animais , Antígenos de Helmintos/uso terapêutico , Brugia Malayi/imunologia , Feminino , Proteínas de Helminto/metabolismo , Interações Hospedeiro-Parasita , Sistema Imunitário , Imunoglobulina G/metabolismo , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Microfilárias , Estreptozocina
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 142: 324-30, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25706603

RESUMO

The Pr(3+)/Yb(3+) co-doped La2O3 and La(OH)3 nano-phosphors have been synthesized through solution combustion method. The structure and morphology of the samples have been studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The physical and optical properties of the samples have been measured and compared. A broad intense infrared emission centered at 850nm due to (1)I6→(1)G4 transition along with sharp green emission centerd at 513nm due to (3)P0→(3)H4 transition are observed on excitation with 976nm laser. The emission intensity of Pr(3+) is optimized with concentration and it is maximum at 0.08mol%. The annealed samples are found to be more crystalline and emit larger photoluminescence due to removal of quenching centers. The power dependent study of green upconversion emission indicates the involvement of two photons. The phosphor in La(OH)3 phase is more stable though the photoluminescence emission is slightly weak. La(OH)3 is less toxic compared to La2O3 and is biocompatible. It generates more heat and can be used in biothermal treatment.


Assuntos
Lantânio/química , Substâncias Luminescentes/química , Óxidos/química , Praseodímio/química , Itérbio/química , Raios Infravermelhos , Luminescência , Modelos Moleculares , Nanoestruturas/química , Difração de Raios X
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 357-62, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25233026

RESUMO

We report the structural and optical properties of Yb(3+), Pr(3+) co-doped Y2O3 nano-phosphor synthesized through solution combustion method. The structural studies reveal the nano-crystalline structure of the sample. The energy dispersive spectroscopy (EDS) measurements confirm the presence of Y, O, Pr and Yb elements in the sample. Fourier transform infrared studies show the vibrational features of the samples. The fluorescence spectra of the samples have been monitored on excitation with 976 nm and the intense green upconversion emission observed at 552 nm is due to (3)P0→(3)H5 electronic transition. The concentration of Pr(3+) ion in the sample is optimized and the fluorescence intensity is maximum at 0.08 mol% of Pr(3+). The power dependence studies reveal the involvement of two photons in the emission process. The possible mechanism of upconversion has been discussed on the basis of schematic energy level diagram. The sample annealed at higher temperature enhances the fluorescence intensity up to 8 times and this enhancement is discussed in terms of the removal of optical quenching centers. The nano-phosphor can be applicable in the field of display devices and green laser.


Assuntos
Nanoestruturas/química , Praseodímio/química , Itérbio/química , Técnicas de Química Sintética , Medições Luminescentes , Microscopia Eletrônica de Transmissão , Óptica e Fotônica , Oxigênio/química , Fótons , Análise Espectral/métodos , Temperatura , Difração de Raios X , Ítrio/química
15.
J Med Entomol ; 51(4): 785-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25118410

RESUMO

Five types of long-lasting insecticidal nets (LNs), namely, Olyset, Netprotect, PermaNet, DuraNet, and Interceptor, were tested after 20 washes for efficacy in terms of mortality, deterrence effect, blood-feeding inhibition, and induced exophily of the malaria vector Anopheles fluviatilis in experimental huts in Malkangiri district of Odisha State, India. Efficacy of the three synthetic pyrethroids (SPs) used in the LNs was also analyzed. Use of LNs reduced the entry of An. fluviatilis into the huts by 73.3-83.2%, and the five LNs were comparable in terms of deterrence. The exit rate of An. fluviatilis from the huts with untreated net was 56.3%, and relative to this, Olyset followed by DuraNet induced significantly a higher exophily. In contrast, the exit rate was significantly lower with Interceptor. Among the three SPs, permethrin induced significantly greater exophily relative to the untreated control, and as a result of this, permethrin-treated Olyset produced a lower mortality. Blood-feeding rate of An. fluviatilis was significantly lower with all the five LNs than the control. Similarly, all the three SPs significantly inhibited blood feeding compared with the control. Interceptor and DuraNet, both alphacypermethrin-treated LNs, caused relatively a higher mortality of An. fluviatilis than the other LNs. The five brands of LNs and three SPs tested in the current study were equally effective in terms of deterrence and blood-feeding inhibition; only exiting and killing effect differed among them. Permethrin-treated LNs induced greater exophily, while, overall, alphacypermethrin-treated LNs killed more An. fluviatilis that entered the huts. Advantage of deterrence, excito-repellent, and killing effects of LNs and appropriate selection of SP for net treatment are discussed in this paper.


Assuntos
Anopheles , Insetos Vetores , Inseticidas/administração & dosagem , Mosquiteiros , Animais , Comportamento Alimentar , Feminino , Índia , Malária/prevenção & controle , Malária/transmissão
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 132: 599-603, 2014 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24892540

RESUMO

We report Eu3+, Sm3+ co-doped La(OH)3 nano-crystalline red emitting phosphor prepared following combustion synthesis protocol. The structural and morphological information about the synthesized samples have been explored using X-ray diffraction (XRD) and transmission electron microscopic (TEM) techniques. The optical properties of the samples have been investigated under 355 nm laser excitations. The sample emits intense red emissions at 625 and 707 nm due to 5D0→7F2 and 5D0→7F4 transitions in Eu3+ ion, respectively. The concentrations of both, Eu3+ and Sm3+ in the samples were optimized at 1 mol% to get maximum fluorescence. The presence of Sm3+ in the Eu3+ doped sample enhances the emission intensity up to two times. The samples annealed at higher temperature show significant enhancement in the emission intensity. The life time studies show an efficient energy transfer from Sm3+ to Eu3+ ions and have been discussed with the help of schematic energy level diagram. This enhancement in the emission intensity is discussed in terms of the rare earth ion concentration, annealing temperature and energy transfer.


Assuntos
Európio/química , Lantânio/química , Luminescência , Fenômenos Ópticos , Samário/química , Lasers , Nanopartículas/ultraestrutura , Espectrometria por Raios X , Termodinâmica , Difração de Raios X
17.
Artigo em Inglês | MEDLINE | ID: mdl-22659282

RESUMO

In the present work, Sm(3+) doped La(OH)(3) nano-phosphor (~40 nm) has been synthesized using combustion synthesis method and detailed structural and spectroscopic characterizations are carried out. On excitation with 532 nm, several photoluminescence peaks extending over green to NIR regions have been observed and assigned to be due to 4f-4f transitions of Sm(3+) ions. A bright orange-red perception is observed in annealed sample, which is 10 times higher than as synthesized sample. Time resolved emission spectroscopy reveals pronounced effect of heating, which induce good crystalline in the host.


Assuntos
Lantânio/química , Luminescência , Nanopartículas/química , Tamanho da Partícula , Temperatura Alta , Nanopartículas/ultraestrutura , Samário/química , Espectrometria de Fluorescência , Difração de Raios X
18.
East Mediterr Health J ; 18(1): 70-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22360014

RESUMO

The Eastern Mediterranean Region of the World Health Organization is facing an increasing burden of vector-borne diseases. Progress in controlling these diseases is compromised by the limited number of vector control interventions, most of which rely on the use of pesticides. Seventeen countries of the Region participated in a global survey that aimed to map and document registration and management practices for public health pesticides. This paper aims to draw the attention of policy- and decision-makers to the challenges the Region is facing in managing public health pesticides properly to control disease vectors and, based on the outcome of the survey, recommends a set of actions to guide national policy and to strengthen national capacity for the sound management and judicious use of public health pesticides.


Assuntos
Vetores de Doenças , Exposição Ambiental/prevenção & controle , Política de Saúde , Controle de Pragas , Praguicidas/efeitos adversos , Animais , Regulamentação Governamental , Humanos , Região do Mediterrâneo , Controle de Qualidade
19.
Appl Biochem Biotechnol ; 166(3): 563-75, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22081331

RESUMO

A laccase has been purified from the liquid culture growth medium containing bagasse particles of Fomes durissimus. The method involved concentration of the culture filtrate by ultrafiltration and anion exchange chromatography on diethyl aminoethyl cellulose. The sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis both gave single protein band indicating that the enzyme preparation was pure. The molecular mass of the purified laccase determined from SDS-PAGE analysis was 75 kDa. Using 2,6-dimethoxyphenol as the substrate, the determined K (m) and k (cat) values of the laccase are 182 µM and 0.35 s(-1), respectively, giving a k (cat)/K (m) value of 1.92 × 10(3) M(-1) s(-1). The pH and temperature optimum were 4.0 and 35 °C, respectively. The purified laccase has yellow colour and does not show absorption band around 610 nm found in blue laccases. Moreover, it transformed methylbenzene to benzaldehyde in the absence of mediator molecules, property exhibited by yellow laccases.


Assuntos
Benzaldeídos/química , Celulose/química , Coriolaceae/enzimologia , Proteínas Fúngicas/química , Lacase/química , Tolueno/química , Cromatografia DEAE-Celulose , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Lacase/isolamento & purificação , Peso Molecular , Pirogalol/análogos & derivados , Pirogalol/química , Especificidade por Substrato , Temperatura , Ultrafiltração
20.
Med Phys ; 39(6Part11): 3736, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28517136

RESUMO

PURPOSE: To study the effect of the virtual wedge and physical wedge filters on the surface and build-up region doses for 6 and 15MV high-energy photon beams for different field sizes and various source to surface distance(SSD). METHODS: The measurements were made in water equivalent (PMMA) solid phantom in the build-up region at various SSD for various field sizes using virtual and physical wedge filters having different angles. A parallel-plate ion chamber (Markus) was used to measure the percent depth doses at surface and buildup region. Plane parallel ion chamber with fixed plate separation on the surface and buildup region would perturbate the dose measured, to get the proper dose over response correction factor was used. RESULTS: The percentage depth dose at surface (PDD0) increased as the field size increased for open, virtual, and physical wedged beams. For open, 30 degree physical, and virtual wedged beams, the surface doses were found to be 15.4%, 11.2%, and 15.2% with 6-MV photons and 11.2%, 9.4%, 11.2% with 15-MV photons, respectively, at 10 × 10 cm2 field size at 100cm SSD.As SSD increases percentage depth dose at surface (PDD0) decreases for open,physical and virtual wedge field. CONCLUSIONS: Percentage depth dose at surface (PDD0) of virtual wedged beams were similar to those of open beams. PDD0 of physical wedged beams were lower than those of open and virtual wedged beams. Surface doses for both PW and VW increases with field size and small increase in surface dose for both PW and VW fields as wedge angle increases especially for large fields.

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