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1.
Int J Biol Macromol ; 275(Pt 1): 133586, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38960242

RESUMO

In the face of agricultural challenges posed by both abiotic and biotic stressors, phytopathogens emerge as formidable threats to crop productivity. Conventional methods, involving the use of pesticides and microbes, often lead to unintended consequences. In addressing this issue, ICAR -Indian Institute of Oilseeds Research (ICAR-IIOR) has developed a chitosan-based double-layer seed coating. Emphasizing crop input compatibility, entrapment, and characterization, the study has yielded promising results. The double-layer coating on groundnut seeds enhanced germination and seedling vigor. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed the structural changes and entrapment of crop inputs. The persistence of T. harzianum (Th4d) and Bradyrhizobium sp. in chitosan blended film in studied soils revealed that viable propogules of Th4d were recorded in double layer treatment combination with 3.54 and 3.50 Log CFUs/g of soil (colony forming units) and Bradyrhizobium sp. with 5.34 and 5.27 Log CFUs/g of soil at 90 days after application (DAA). Root colonization efficacy studies of Th4d and Bradyrhizobium sp. in groundnut crop in studied soils revealed that, maximum viable colonies were observed at 45 days after sowing (DAS). This comprehensive study highlights the potential of chitosan-based double-layer seed coating providing a promising and sustainable strategy for stress management in agriculture.

2.
Luminescence ; 31(8): 1519-1523, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27073058

RESUMO

The speciation of a particular element in any given matrix is a prerequisite to understanding its solubility and leaching properties. In this context, speciation of uranium in lanthanum zirconate pyrochlore (La2 Zr2 O7 = LZO), prepared by a low-temperature combustion route, was carried out using a simple photoluminescence lifetime technique. The LZO matrix is considered to be a potential ceramic host for fixing nuclear and actinide waste products generated during the nuclear fuel cycle. Special emphasis has been given to understanding the dynamics of the uranium species in the host as a function of annealing temperature and concentration. It was found that, in the LZO host, uranium is stabilized as the commonly encountered uranyl species (UO22+ ) up to a heat treatment of 500 °C at the surface. Above 500 °C, the uranyl ion is diffused into the matrix as the more symmetric octahedral uranate species (UO66- ). The uranate ions thus formed replace the six-coordinated 'Zr' atoms at regular lattice positions. Further, it was observed that concentration quenching takes place beyond 5 mol% of uranium doping. The mechanism of the quenching was found to be a multipolar interaction. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Lantânio/química , Luminescência , Nióbio/química , Oxigênio/química , Temperatura , Urânio/química , Zircônio/química
3.
Indian J Cancer ; 53(2): 292-295, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28071630

RESUMO

BACKGROUND: Ovarian tumors are uncommon in childhood and constitute around 1% of childhood malignancies. Two thirds of pediatric ovarian tumors are germ cell tumors. Epithelial ovarian tumors and stromal tumors are less frequent. We share our experience in childhood ovarian cancers, analyzing a series of cases with respect to the clinical profile, treatment and survival. METHODS: All newly diagnosed ovarian tumors in children up to 14 years of age, registered in our Pediatric Oncology Division between January 2000 and December 2009 were retrospectively reviewed. OBSERVATIONS: There were 47 patients with newly diagnosed ovarian tumors. The mean age at presentation was 10.0 ± 3.4 years. The most common symptoms at presentation were acute abdominal pain (48.9%) and abdominal mass (40.4%). Precocious puberty was uncommon (6.3%). Histology was germ cell tumors in 44 cases and nongerm cell tumors in three cases. The benign teratomas (mature and immature grade 1 and 2; n=9) underwent complete surgical resection alone; none had recurrence on follow up. Of the remaining 35 GCTs, 31 patients were given chemotherapy and 4 refused treatment.26 out of the 31 patients completed chemotherapy with BEP (bleomycin, etoposide, cisplatin) regimen with acceptable toxicities. 5 children i.e.; (19.2%) developed recurrence. At a median follow up of 80 months, 10 year disease free survival was 80.8 ± 7.7% and 10 year overall survival was 92.7 ± 4.9%. CONCLUSION: Germ cell tumors are the most common ovarian malignancy in children. With surgery and chemotherapy using BEP, good outcome can be expected in these patients.


Assuntos
Neoplasias Ovarianas , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Neoplasias Ovarianas/patologia , Centros de Atenção Terciária , Fatores de Tempo
4.
Luminescence ; 31(2): 551-556, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26278621

RESUMO

Incorporating the Gd(3+) rare earth ion in the LiCaBO3 host lattice resulted in narrow-band UV-B emission peaking at 315 nm, with excitation at 274 nm. The LiCaBO3:Gd(3+) phosphor was synthesized via the solid-state diffusion method. The structural, morphological and luminescence properties of this phosphor were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and photoluminescence (PL) spectroscopy. Electron paramagnetic resonance (EPR) characterization of the as-prepared phosphors is also reported here. XRD studies confirmed the crystal formation and phase purity of the prepared phosphors. A series of different dopant concentrations was synthesized and the concentration-quenching effect was studied. Critical energy transfer distance between activator ions was determined and the mechanism governing the concentration quenching is also reported in this paper.


Assuntos
Boro/química , Cálcio/química , Gadolínio/química , Lítio/química , Oxigênio/química , Raios Ultravioleta , Luminescência , Difração de Raios X
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 363-70, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25233027

RESUMO

A titania mineral (obtained from East coast, Orissa, India) was investigated by X-ray diffraction (XRD), photoacoustic spectroscopy (PAS), Raman and Electron Paramagnetic Resonance (EPR) studies. XRD studies indicated the presence of rutile (91%) and anatase (9%) phases in the mineral. Raman investigation supported this information. Both rutile and anatase phases have tetragonal structure (rutile: space group P4(2)/mnm, a=4.5946(1) Å, c=2.9597(1) Å, V=62.48(1) (Å)(3), Z=2; anatase: space group I4(1)/amd, 3.7848(2) Å, 9.5098(11) Å, V=136.22(2) (Å)(3), Z=4). The deconvoluted PAS spectrum showed nine peaks around 335, 370, 415,485, 555, 605, 659, 690,730 and 785 nm and according to the ligand field theory, these peaks were attributed to the presence of V(4+), Cr(3+), Mn(4+) and Fe(3+) species. EPR studies revealed the presence of transition metal ions V(4+)(d(1)), Cr(3+)(d(3)), Mn(4+)(d(3)) and Fe(3+)(d(5)) at Ti(4+) sites. The EPR spectra are characterized by very large crystal filed splitting (D term) and orthorhombic distortion term (E term) for multiple electron system (s>1) suggesting that the transition metal ions substitute the Ti(4+) in the lattice which is situated in distorted octahedral coordination of oxygen. The possible reasons for observation of unusually large D and E term in the EPR spectra of transition metal ions (S=3/2 and 5/2) are discussed.


Assuntos
Análise Espectral/métodos , Titânio/química , Cromo/química , Espectroscopia de Ressonância de Spin Eletrônica , Índia , Ferro/química , Manganês/química , Minerais/química , Análise Espectral Raman , Vanádio/química , Difração de Raios X
6.
Dalton Trans ; 41(39): 12023-30, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22903181

RESUMO

The present study describes the structural and luminescent properties of SrSnO(3) nanorods containing Eu(3+) ions. Based on Rietveld refinement of XRD patterns corresponding to both undoped and europium doped SrSnO(3) nanorods, it is inferred that the average bond lengths of Sr-O1 linkages, which have a square planar geometry around Sr(2+) in the SrO(12) polyhedra present in SrSnO(3), remained unaffected with Eu(3+) incorporation into the lattice. However, the average bond lengths of shorter Sr-O2 linkages increase and longer Sr-O2 linkages decrease with Eu(3+) doping into the SrSnO(3) lattice. A lack of variation in the lattice parameters of SrSnO(3) with doped Eu(3+) ions is explained based on mutually compensating changes in the average bond lengths of the Sr-O2 linkages in the unit cell. Luminescence studies have confirmed that Eu(3+) ions occupy the centrosymmetric Sr(2+) site only up to 2 at%, beyond which Eu(3+) ions exist in a significantly distorted environment (grain boundaries). Beyond 3%, incorporation of Eu(3+) ions into the SrSnO(3) lattice leads to the formation of a Eu(2)Sn(2)O(7) phase. From the EPR studies it is confirmed that around 5% of the incorporated Eu(3+) ions get converted to Eu(2+) ions and they occupy Sr(2+) sites in the lattice.

7.
J Microbiol Biotechnol ; 22(8): 1084-91, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22713984

RESUMO

Xylooligosaccharides are functional foods mainly produced during the hydrolysis of xylan by physical, chemical, or enzymatic methods. In this study, production of xylobiose was investigated using oil palm empty fruit bunch fiber (OPEFB) as a source material, by chemical and enzymatic methods. Xylanase-specific xylan hydrolysis followed by xylobiose production was observed. Among different xylanases, xylanase from FXY-1 released maximum xylobiose from pretreated OPEFB fiber, and this fungal strain was identified as Aspergillus terreus and subsequently deposited under the accession Number MTCC- 8661. The imperative role of lignin on xylooligosaccharides enzymatic synthesis was exemplified with the notice of xylobiose production only with delignified material. A maximum 262 mg of xylobiose was produced from 1.0 g of pretreated OPEFB fiber using FXY-1 xylanase (6,200 U/ml) at pH 6.0 and 45° C. At optimized environment, the yield of xylobiose was improved to 78.67 g/100 g (based on xylan in the pretreated OPEFB fiber).


Assuntos
Aspergillus/enzimologia , Aspergillus/metabolismo , Dissacarídeos/biossíntese , Xilosidases/metabolismo , Biomassa , Frutas/metabolismo , Plantas/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-21524936

RESUMO

Electron paramagnetic resonance (EPR) studies were conducted on gamma irradiated polycrystalline sample of thorium nitrate pentahydrate, Th(NO(3))(4)·5H(2)O, in the temperature range of 100-300 K. The most prominent species with triplet hyperfine structure in the EPR spectrum was identified as NO(2). The EPR spectrum gave evidence for the stabilization of NO(2) in at least three different sites slightly differing in spin Hamiltonian parameters (Site(1): g(x)=2.0042, g(y)=1.9911, g(z)=2.0020, A(x)=54.20 G, A(y)=48.50 G and A(z)=65.25 G; Site(2): g(x)=2.0042, g(y)=1.9911, g(z)=2.0020, A(x)=54.20 G, A(y)=48.50 G and A(z)=67.85 G; Site(3): g(x)=2.0045, g(y)=1.9911, g(z)=2.0015, A(x)=54.20 G, A(y)=49.05 G and A(z)=72.45 G). The EPR spectra for Site(1) revealed molecular dynamics of NO(2) from a slow motion region to fast motion region as the sample temperature was varied from 100 to 300 K. This led to a change in EPR spectrum from orthorhombic to axial, indicating preferred rotation of NO(2) molecule about the O-O bond direction. However, the NO(2) molecule at Site(2) was found to be rigid throughout the entire temperature range. The differences in the mobility of NO(2) molecules occupying the two sites could be attributed to the fact that in one case NO(2) was bonded to thorium or water and in the other case it was weakly bound. The NO(2) bound to thorium through two oxygen atoms or bound to thorium on one side through one oxygen atom and hydrogen bonded to water on the other side remains rigid throughout the entire temperature range, while NO(2) situated at interstitial sites or adsorbed on the surface exhibits mobility with increase in temperature above 100K.


Assuntos
Dióxido de Nitrogênio/química , Compostos de Tório/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Raios gama , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Temperatura
9.
Appl Radiat Isot ; 68(6): 1128-31, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20080415

RESUMO

Energy dispersive X-ray fluorescence (EDXRF) methods have been developed for the direct determination of 14 trace metallic impurities in graphite powder without any need for sample dissolution. Using synthetic standards, calibration curves were established for different elements after optimizing the spectrometer parameters. Two synthetic samples were analyzed to evaluate the performance of the developed analytical methods. The estimates for most of the analytes were in good agreement with the added amounts. Three graphite powder samples were analyzed by the present method as well as by D.C. arc emission spectrometric technique for comparison and the agreement between the analyte values determined, using both methods was good. Samples in pellet form were analyzed using a separate calibration with standards in pellet form. The present method is rapid, as it alleviates the need for any chemical treatment and gives good precision.

10.
Artigo em Inglês | MEDLINE | ID: mdl-7777913

RESUMO

Blastocystis hominis has long been described as a non pathogenic protozoan parasite until recently when claims have been made that it can result in pathogenic conditions. Of the 729 stool samples (614 from survey and 115 from pediatric wards) examined, 18.1% of them were found to be positive for one or more intestinal protozoan cyst. The commonest was Giardia intestinalis (8.4%) Followed by Entamoeba coli (7.1%) and Entamoeba histolytica (5.1%) in the normal children without symptoms of diarrhea. When diarrheic stools were examined, the commonest parasite encountered was Giardia (20.4%), followed by E. coli (15.9%) and E. histolytica (9.7%). Blastocystis was observed in 4.4% of the children who had diarrhea and 1.1% among the children taken from the normal population in the rural areas.


Assuntos
Infecções por Blastocystis/epidemiologia , Blastocystis hominis , Enteropatias Parasitárias/epidemiologia , Adolescente , Animais , Criança , Pré-Escolar , Diarreia/parasitologia , Feminino , Humanos , Lactente , Malásia/epidemiologia , Masculino , Prevalência
12.
Asia Pac J Public Health ; 7(1): 21-5, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8074940

RESUMO

Fecal specimens collected from 456 school children in Gombak, Malaysia, revealed an overall prevalence rate of 62.9%. The most common parasite found was Trichuris trichiura (47.1%) followed by Giardia intestinalis (14.7%), Entamoeba coli (11.4%), Entamoeba histolytica (9.9%) and Ascaris lumbricoides (7.9%). Infection rates were high among the Indonesian immigrant workers' children (90%) followed by the Orang Asli (79.5%), Malay (59.4%) and Indians (36.4%). Females (66.3%) had a higher prevalence rate than the males (58.5%). The prevalence of infection was found to be associated with the socio-economic status, water supply, sanitary disposal of feces and family size. Albendazole administered as a single dose (400 mg) was found to be effective against Ascaris (100%) and hookworm (92.3%) but was not effective against Trichuris (39.2%).


Assuntos
Helmintíase/epidemiologia , Infecções por Protozoários/epidemiologia , Adolescente , Albendazol/uso terapêutico , Ascaríase/tratamento farmacológico , Criança , Feminino , Helmintíase/economia , Infecções por Uncinaria/tratamento farmacológico , Humanos , Malásia/epidemiologia , Masculino , Prevalência , Infecções por Protozoários/economia , Fatores Socioeconômicos , Tricuríase/tratamento farmacológico
13.
World Health Forum ; 15(3): 236-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7945748

RESUMO

An outline is given of a simple cost-effective strategy aimed at the immunization of all children and pregnant women residing in the plantation sector of Malaysia. It is based on a partnership between government, nongovernmental organizations and the private sector, and is supported by UNICEF.


PIP: A cost-effective strategy aimed at the immunization of all children and pregnant women residing in the plantation sector of Malaysia is outlined. It is based on a partnership between government, nongovernmental organizations and the private sector, and is supported by UNICEF. Over a million people reside on the Malaysian plantation estates: only 17% of the estates have their own hospitals; immunization services exist on only 1.5%; 40% of the estates are at least 5 kilometers from the nearest government health facility; and 64% lack transport for workers and their dependents to seek care away from the plantations. Two nongovernmental organizations, the Malaysian Paediatric Association and the Malaysian Society of Health, initiated discussions with the United Planting Association of Malaysia. A pilot study was undertaken by the groups on 6 estates in Selangor State, which included all the children at their first birthday. Tuberculosis, diphtheria/pertussis/tetanus, poliomyelitis, and measles immunization coverages were 88%, 44%, 59%, and 66%, respectively. The association of plantations accepted the organizations' proposals for all estates to: register all births; provide free transportation to government health clinics for the immunization of all eligible children and pregnant women; and enforce immunization schedules and record-keeping. The Ministry of Health agreed to provide free immunization of children and pregnant women; send mobile teams to estates that could assemble 20 or more eligible people for immunization; provide the estates with educational materials dealing with immunization; arrange that the maintenance of the cold chain be supervised by local medical officers of health; consider the training of estate hospital assistants with the help of the nongovernmental organizations. The total immunization plan was launched in September 1990. A manual was distributed to the estate managers, hospital assistants on the estates, and the medical officers who would implement and monitor the program. It is expected that total child immunization will be achieved in the foreseeable future in the estate sector.


Assuntos
Diretrizes para o Planejamento em Saúde , Imunização , Relações Interinstitucionais , Administração em Saúde Pública , Sociedades Médicas/organização & administração , Pré-Escolar , Análise Custo-Benefício , Feminino , Humanos , Imunização/economia , Imunização/métodos , Malásia , Projetos Piloto , Gravidez , População Rural
19.
Trop Geogr Med ; 35(4): 337-42, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6670116

RESUMO

A survey of 4.112 primary school children living in and around Kuala Lumpur, Malaysia, revealed that 12.9% of the children were infested with Pediculus humanus capitis. Indians (28.3%) and Malays (18.9%) have a higher prevalence than Chinese (4.6%). The higher prevalence among Indians and Malays correlates well with their lower socio-economic status in the community; long hair also contributes to the higher rates of pediculosis among them. The prevalence rate was found to be related to socio-economic status, length of hair, family size, age, crowding and personal hygiene. Treatment with 0.2% and 0.5% malathion in coconut oil gave cure rates of 93% and 100%. Treatment with gammexane and actellic at 0.5% concentration gave a cure rate of 100% against adults and nymphs of Pediculus humanus capitis.


Assuntos
Infestações por Piolhos/epidemiologia , Fatores Etários , Criança , Etnicidade , Características da Família , Feminino , Humanos , Infestações por Piolhos/tratamento farmacológico , Infestações por Piolhos/prevenção & controle , Infestações por Piolhos/transmissão , Malation/uso terapêutico , Malásia , Masculino , Couro Cabeludo , Fatores Sexuais , Fatores Socioeconômicos
20.
Am J Trop Med Hyg ; 30(3): 734-8, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7258487

RESUMO

A survey of 308,101 primary school children in Peninsular Malaysia conducted in 1979 by the School Health Services, Ministry of Health, Malaysia, revealed that 10.7% of children were infested with Pediculus humanus capitis. The prevalence rate was higher in the economically less advanced states of Terenganu (34%), Kelantan (23%), and Perlis (21%) than in the other states (4-13%). Of 14,233 school children examined in the State of Melaka, 26% of Indians, 18.7% of Malays, 6.1% of Europeans, and 0.7% of Chinese had pediculosis. The prevalence rate, which has remained unchanged over the past 5 years, does not appear to vary with age but is higher in children with long hair and those from the lower socioeconomic groups. Boys have a lower infestation rate than do girls. The higher incidence in Indians and Malays correlates well with their lower socioeconomic status in the community, and their cultural habit of maintaining longer hair than do the Chinese. The difference become less apparent in the higher socioeconomic groups.


Assuntos
Infestações por Piolhos/epidemiologia , Fatores Etários , Criança , Etnicidade , Feminino , Cabelo/parasitologia , Humanos , Malásia , Masculino , Fatores Sexuais , Fatores Socioeconômicos
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