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1.
Bioinformation ; 20(6): 630-633, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39131532

RESUMO

Orthodontists should know variation in thickness of infrazygomatic crest region according to maturation status of patients. Therefore, it is of interest to evaluate the thickness of bone at infrazygomatic crest region and to correlate the thickness of bone with cervical vertebrae maturation index (CVMI) incorporating CBCT.A retrospective analysis of 120 patients' CBCT scans60 of them male and 60 female-was carried out. The thickness of the bone was determined at five locations. Using CBCT, the cervical vertebral maturation was created and the Hassel-Farmann index was used for analysis. A lone researcher conducted all of the measurements. Bone thickness of infrazygomatic arch at all five locations was found to increase as the maturation stage progressed from initiation stage to maturation stage. Then there was decrease in the bone thickness in completion stages compared to maturation stage. The thickness of bone at infrazygomatic arch is significantly correlated with CVM stages as determined by CBCT.

2.
Bioinformation ; 20(4): 349-352, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38854772

RESUMO

The differences in the effects of orthodontic treatment on airway and craniocervical posture in patients with OSA (obstructive sleep apnea) having skeletal class II high-angle malocclusion is of interest. Hence, 48 individuals with OSA and skeletal class II high-angle malocclusion were chosen from among all patients in need of orthodontic therapy. Every patients had CBCT (cone beam computed tomography) taken both before and after receiving orthodontic therapy. All parameters were assessed on the lateral cephalogram from CBCT in order to assess the indices of craniocervical posture, hyoid position, skeletal and dental conditions. Parameters of upper airway (position of hyoid) showed statistically significant increase in values after orthodontic treatments. Thus, there was increase in values of dimensions of upper airway, post orthodontic treatment. Hence, orthodontic therapy help improve the upper airway morphology and craniocervical posture in patients of OSA with hyperdivergent skeletal class II malocclusion.

3.
J Wound Care ; 32(Sup3): S4-S8, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36930280

RESUMO

Surgical site infections (SSIs) are treated using topical antiseptics and systemic antibiotics, but some cases are unresponsive to such regimens. This case study reports the effective healing of an SSI by a chitosan wound dressing (MaxioCel; Axio Biosolutions Private Limited, India) in a 63-year-old female patient. The patient presented with an infected, hard-to-heal wound in the abdominal region, developed after a hernia surgery, and was initially treated with standard procedures. However, due to the continuous progression of infection, a highly absorbent, bioactive microfibre dressing was selected for the treatment and was continued for two months with alternate-day dressing changes. After 60 days of treatment, wound healing was observed, along with remission from the infection, as well as reduction in exudate level and pain. The use of chitosan wound dressing in management of hard-to-heal infected wounds provides efficient remission of SSI and a faster healing rate.


Assuntos
Anti-Infecciosos Locais , Quitosana , Feminino , Humanos , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/tratamento farmacológico , Quitosana/uso terapêutico , Bandagens , Antibacterianos/uso terapêutico , Anti-Infecciosos Locais/uso terapêutico
4.
Bioinformation ; 19(13): 1394-1398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38415035

RESUMO

Three aesthetic indices namely aesthetic component of index of orthodontic treatment needs (IOTN -AC), dental aesthetic index (DAI) and dental aesthetics screening index (DESI) were compared in orthodontic treatment. 242 participants (160 female and 82 male) who were interested in orthodontic treatment participated. The individuals' ages ranged from 16-25 years. Three aesthetic indices namely IOTN -AC, DAI and DESI were evaluated for each participant. The overall accuracy of DAI, AC-IOTN and DESI in assessment of dental aesthetics in orthodontic treatment was 62%, 68% and 64% respectively. The Negative predictive value (NPV) was higher than Positive predictive value (PPV) for all indices. The sensitivity was greater than specificity for all indices. It was observed that values of sensitivity, specificity, PPV and NPV were high for AC-IOTN. The findings were significant statistically (p<0.05).

5.
Front Nutr ; 8: 747956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621776

RESUMO

An entirely unknown species of coronavirus (COVID-19) outbreak occurred in December 2019. COVID-19 has already affected more than 180 million people causing ~3.91 million deaths globally till the end of June 2021. During this emergency, the food nutraceuticals can be a potential therapeutic candidate. Curcumin is the natural and safe bioactive compound of the turmeric (Curcuma longa L.) plant and is known to possess potent anti-microbial and immuno-modulatory properties. This review paper covers the various extraction and quantification techniques of curcumin and its usage to produce functional food. The potential of curcumin in boosting the immune system has also been explored. The review will help develop insight and new knowledge about curcumin's role as an immune-booster and therapeutic agent against COVID-19. The manuscript will also encourage and assist the scientists and researchers who have an association with drug development, pharmacology, functional foods, and nutraceuticals to develop curcumin-based formulations.

6.
Rev Sci Instrum ; 92(3): 034704, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820068

RESUMO

A horizontal test facility is set up at the Raja Ramanna Centre for Advanced Technology to test the superconducting radio frequency dressed cavities. Along with the cryomodule, control instrumentation, and the power coupler, this facility incorporates a high-power solid-state amplifier for establishing the desired cavity voltage gradient during the testing. This article describes the design, construction, rigorous testing, and measured results of this high-power solid-state radio frequency amplifier and its constituent components. Its maximum output power is 36 kW (average) at the operating frequency of 650 MHz. Its main features are its modular and scalable design with in-house developed constituent components. These components include 500 W, 20 dB gain modules, novel two-tier radial dividers, combiners, power sensors, and aperture-coupled directional couplers. Their excellent reprise performance for the multiple quantities confirms the design methodology presented here. The measured wall plug efficiency of this 36 kW amplifier is 43.6%, and its power gain is 86 dB. The designed radial combiner is highly efficient (power-combining efficiency of 98.4%), and the directional coupler exhibits a very low loss (insertion loss of 0.05 dB).

7.
Int J Appl Basic Med Res ; 11(2): 90-94, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912428

RESUMO

CONTEXT: The adverse effects associated with traditional adjunctive chemical agents in the management of gingivitis has stimulated research into search for alternate molecules including herbal products. Aims-To compare the effects of oral curcumin gel as an adjunct to scaling and root planing (SRP) with the effects achieved by SRP alone by assessing their effects on plaque, gingival inflammation and gingival bleeding. MATERIALS AND METHODS: Sixty patients in the age group of 20-60 years were recruited employing inclusion and exclusion criteria. Study population was randomly divided into two groups. Group A-test group was instructed to use twice daily the experimental curcumin gel after initial SRP. Group B-control group received only SRP. Parameters recorded were plaque index (PI), gingival index (GI) and sulcus bleeding index (SBI) on day 0 (baseline), days 7, 14, and 21 along with subjective assessment of any reported untoward side effect. Data was analyzed statistically. RESULTS: The PI, GI and SBI decreased in both the test group and control group from day 0 to day 21 consecutively. Intergroup comparison shows that all the parameters were statistically significant in Group A (P < 0.001) as compared to Group B. CONCLUSION: Curcumin gel has significant antiplaque and anti-inflammatory effect in the treatment of gingivitis and can be effectively employed as an adjunct to SRP.

8.
ACS Omega ; 5(17): 10077-10088, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32391495

RESUMO

Aspergillus fumigatus causes several nosocomial pulmonary infections and accounts for high morbidity and mortality rate globally. Among various virulence factors, 1,8-dihydroxynaphthalene-melanin plays an important role in the survival during unfavorable conditions both in vivo and in vitro, masks various molecular patterns associated with A. fumigatus, and protects it from the host immune system. In the present study, we aim to understand the potential of cis-9-hexadecenal as an antimelanogenic compound and its role in modulating other associated virulence factors in A. fumigatus. cis-9-Hexadecenal is a bioactive compound that belongs to C16 mono-unsaturated fatty-aldehyde groups. Minimum effective concentration of cis-9-hexadecenal affecting A. fumigatus melanin biosynthesis was determined using broth microdilution method. The spectrophotometric analysis revealed reduced melanin content (91%) and hydrophobicity (59%) at 0.293 mM of cis-9-hexadecenal. Cell surface organizational changes using electron microscopy showed altered demelanized smooth A. fumigatus conidial surface without any protrusions after cis-9-hexadecenal treatment. The transcript analysis of polyketide synthase (PKS) pksP/alb1 gene was quantified through qRT-PCR which revealed an upregulated expression. Total proteome profiling conducted through LC-MS-MS showed upregulated PKS enzyme but other downstream proteins involved in the 1,8-dihydroxynaphthalene-melanin biosynthesis pathway were absent. The homology modeling of PKS using Expasy's web server predicted that PKS is stable at varied conditions and is hydrophilic in nature. The Ramachandran plot by PROCHECK confirmed the 3-D structure of PKS to be reliable. Docking analysis using AutoDock-4.2.6 predicted the binding of cis-9-hexadecenal and PKS at Thr-264 and Ser-171 residue via hydrogen bonding at a low binding energy of -4.95 kcal/mol.

9.
Ann Bot ; 123(4): 691-705, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30535180

RESUMO

BACKGROUND AND AIMS: Nitrogen (N) levels vary between ecosystems, while the form of available N has a substantial impact on growth, development and perception of stress. Plants have the capacity to assimilate N in the form of either nitrate (NO3-) or ammonium (NH4+). Recent studies revealed that NO3- nutrition increases nitric oxide (NO) levels under hypoxia. When oxygen availability changes, plants need to generate energy to protect themselves against hypoxia-induced damage. As the effects of NO3- or NH4+ nutrition on energy production remain unresolved, this study was conducted to investigate the role of N source on group VII transcription factors, fermentative genes, energy metabolism and respiration under normoxic and hypoxic conditions. METHODS: We used Arabidopsis plants grown on Hoagland medium with either NO3- or NH4+ as a source of N and exposed to 0.8 % oxygen environment. In both roots and seedlings, we investigated the phytoglobin-nitric oxide cycle and the pathways of fermentation and respiration; furthermore, NO levels were tested using a combination of techniques including diaminofluorescein fluorescence, the gas phase Griess reagent assay, respiration by using an oxygen sensor and gene expression analysis by real-time quantitative reverse transcription-PCR methods. KEY RESULTS: Under NO3- nutrition, hypoxic stress leads to increases in nitrate reductase activity, NO production, class 1 phytoglobin transcript abundance and metphytoglobin reductase activity. In contrast, none of these processes responded to hypoxia under NH4+ nutrition. Under NO3- nutrition, a decreased total respiratory rate and increased alternative oxidase capacity and expression were observed during hypoxia. Data correlated with decreased reactive oxygen species and lipid peroxidation levels. Moreover, increased fermentation and NAD+ recycling as well as increased ATP production concomitant with the increased expression of transcription factor genes HRE1, HRE2, RAP2.2 and RAP2.12 were observed during hypoxia under NO3- nutrition. CONCLUSIONS: The results of this study collectively indicate that nitrate nutrition influences multiple factors in order to increase energy efficiency under hypoxia.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Metabolismo Energético , Nitratos/metabolismo , Fatores de Transcrição/genética , Anaerobiose , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Nutrientes/metabolismo , Oxigênio/análise , Fatores de Transcrição/metabolismo
10.
Bioinformation ; 14(7): 393-397, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30262977

RESUMO

Finger millet is a calcium-rich cereal crop of the grass family. The transcriptome data for finger millet is available at NCBI. It is of interest to annotate and characterize starch synthase enzyme from finger millet transcriptome data. Starch synthase plays an important role in the elongation of glucan chains during the formation of starch. The starch synthase enzyme is characterized using three domains (Glyco_transf_5, Glycos_transf_1 and Glyco_trans_1_4). Binding sites for GLC (alpha-d-glucose), PLP (Pyridoxal-5'- phosphate), AMP (Adenosine monophosphate) and GOL (Glycerol) are found. The phylogenetic analysis showed that the finger millet starch synthase is similar to the granule-bound starch synthase of Oryza sativa and Concrete amaricanus. We report the sequence (GenBank accession number KY648917) and the structural model of finger millet starch synthase (PMDB ID: PM0081600).

11.
Ann Bot ; 119(5): 703-709, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27594647

RESUMO

BACKGROUND: Plants require nitrogen (N) for growth, development and defence against abiotic and biotic stresses. The extensive use of artificial N fertilizers has played an important role in the Green Revolution. N assimilation can involve a reductase series ( NO3- → NO2- → NH4+ ) followed by transamination to form amino acids. Given its widespread use, the agricultural impact of N nutrition on disease development has been extensively examined. SCOPE: When a pathogen first comes into contact with a host, it is usually nutrient starved such that rapid assimilation of host nutrients is essential for successful pathogenesis. Equally, the host may reallocate its nutrients to defence responses or away from the site of attempted infection. Exogenous application of N fertilizer can, therefore, shift the balance in favour of the host or pathogen. In line with this, increasing N has been reported either to increase or to decrease plant resistance to pathogens, which reflects differences in the infection strategies of discrete pathogens. Beyond considering only N content, the use of NO3- or NH4+ fertilizers affects the outcome of plant-pathogen interactions. NO3- feeding augments hypersensitive response- (HR) mediated resistance, while ammonium nutrition can compromise defence. Metabolically, NO3- enhances production of polyamines such as spermine and spermidine, which are established defence signals, with NH4+ nutrition leading to increased γ-aminobutyric acid (GABA) levels which may be a nutrient source for the pathogen. Within the defensive N economy, the roles of nitric oxide must also be considered. This is mostly generated from NO2- by nitrate reductase and is elicited by both pathogen-associated microbial patterns and gene-for-gene-mediated defences. Nitric oxide (NO) production and associated defences are therefore NO3- dependent and are compromised by NH4+ . CONCLUSION: This review demonstrates how N content and form plays an essential role in defensive primary and secondary metabolism and NO-mediated events.


Assuntos
Fertilizantes , Interações Hospedeiro-Patógeno , Compostos de Nitrogênio/metabolismo , Nitrogênio/análise , Nitrogênio/metabolismo , Doenças das Plantas/microbiologia , Plantas/metabolismo , Nitrogênio/administração & dosagem , Compostos de Nitrogênio/administração & dosagem
12.
Methods Mol Biol ; 1424: 15-29, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27094407

RESUMO

NO is a free radical with short half-life and high reactivity; due to its physiochemical properties it is very difficult to detect the concentrations precisely. Chemiluminescence is one of the robust methods to quantify NO. Detection of NO by this method is based on reaction of nitric oxide with ozone which leads to emission of light and amount of light is proportional to NO. By this method NO can be measured in the range of pico moles to nano moles range. Using direct chemiluminescence method, NO emitted into the gas stream can be detected whereas using indirect chemiluminescence oxidized forms of NO can also be detected. We detected NO using purified nitrate reductase, mitochondria, cell suspensions, and roots; detail measurement method is described here.


Assuntos
Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Luminescência , Nicotiana/metabolismo
13.
Methods Mol Biol ; 1424: 31-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27094408

RESUMO

In plants, nitrate reductase (NR) is a key enzyme that produces nitric oxide (NO) using nitrite as a substrate. Lower plants such as algae are shown to have nitric oxide synthase enzyme and higher plants contain NOS activity but enzyme responsible for NO production in higher plants is subjected to debate. In plant nitric oxide research, it is very important to measure NO very precisely in order to determine its functional role. A significant amount of NO is being scavenged by various cell components. The net NO production depends in production minus scavenging. Here, we describe methods to measure NO from purified NR and inducible nitric oxide synthase from mouse (iNOS), we also describe a method of measure NO scavenging by tobacco cell suspensions and mitochondria from roots.


Assuntos
Enzimas/metabolismo , Óxido Nítrico/metabolismo , Gases , Luminescência
14.
Gene ; 546(2): 327-35, 2014 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-24875415

RESUMO

In order to gain insights into the mechanism of high nitrogen use efficiency (NUE) of finger millet (FM) the role of Dof2 transcription factor (TF), which is a repressor of genes involved in C/N metabolism was investigated. The partial cDNA fragment of EcDof2 (912-bp; GenBank acc. no. KF261117) was isolated and characterized from finger millet (FM) that showed 63% and 58% homology with Dof2 of Zea mays at nucleotide and protein level, respectively. Its expression studies were carried out along with the activator EcDof1 in two genotypes (GE3885, high protein genotype (HPG); GE1437, low protein genotype (LPG)) of FM differing in grain protein contents (13.8% and 6.2%) showed that EcDof2 is expressed in both shoot and root tissues with significantly (p≤0.05) higher expression in the roots. The diurnal expression of both EcDof1 and EcDof2 in shoots was differential having different time of peak expression indicating a differential response to diurnal condition. Under continuous dark conditions, expression of EcDof1 and EcDof2 oscillated in both the genotypes whereas on illumination, the fold expression of EcDof1 was higher as compared to EcDof2. Under increasing nitrate concentration, EcDof2 expression increases in roots and shoots of LPG while it remains unchanged in HPG. However, the EcDof1 expression was found to increase in both genotypes. Further, time kinetics studies under single nitrate concentration revealed that EcDof2 was repressed in the roots of both genotypes whereas EcDof1 oscillated with time. The EcDof1/EcDof2 ratio measured showed differential response under different light and nitrogen conditions. It was higher in the roots of HPG indicating higher activation of genes involved in N uptake and assimilation resulting in high grain protein accumulation. The results indicate that both light and nitrogen concentration influence Dof1 and Dof2 expression and suggests a complex pattern of regulation of genes influenced by these plant specific TFs. In nutshell, the Dof1/Dof2 ratio can serve as an index for measuring the N responsiveness and NUE of crops and can be further validated by Dof2 knock down approach.


Assuntos
Eleusine/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Genótipo , Luz , Nitrogênio/metabolismo , Fatores de Transcrição/biossíntese , Eleusine/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Proteínas de Armazenamento de Sementes/biossíntese , Proteínas de Armazenamento de Sementes/genética , Sementes/genética , Sementes/metabolismo , Fatores de Transcrição/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-24730937

RESUMO

Electro-osmosis phenomena are studied in a two-dimensional (2D) model disordered porous medium. The flow passages are represented by a network of spatially distributed rectangular channels with random orientations. The channels may represent microfractures in fractured porous media or in a network of interconnected microfractures, pores in a porous medium, or fibers in a fibrous porous material. The linearized equations of electrokinetics are solved numerically in a single channel, and in the 2D network of the channels. The macroscopic electrical conductivity σ and electro-osmotic coupling coefficient ß are computed as functions of the electrical surface potential ζ and such geometrical parameters of the network as the channels' number density and widths, as well as the porosity of the medium. Despite the complexity of the phenomena and the model of porous media that is used, both σ and ß appear to depend on the characteristics of the phenomena and porous media through very simple relations.

16.
Funct Integr Genomics ; 13(2): 179-90, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23435937

RESUMO

In order to understand the molecular basis of high nitrogen use efficiency of finger millet, five genes (EcHNRT2, EcLNRT1, EcNADH-NR, EcGS, and EcFd-GOGAT) involved in nitrate uptake and assimilation were isolated using conserved primer approaches. Expression profiles of these five genes along with the previously isolated EcDof1 was studied under increased KNO3 concentrations (0.15 to 1,500 µM) for 2 h as well as at 1.5 µM for 24 h in the roots and shoots of 25 days old nitrogen deprived two contrasting finger millet genotypes (GE-3885 and GE-1437) differing in grain protein content (13.76 and 6.15 %, respectively). Time kinetics experiment revealed that, all the five genes except EcHNRT2 in the leaves of GE-3885 were induced within 30 min of nitrate exposure indicating that there might be a greater nitrogen deficit in leaves and therefore quick transportation of nitrate signals to the leaves. Exposing the plants to increasing nitrate concentrations for 2 h showed that in roots of GE-3885, NR was strongly induced while GS was repressed; however, the pattern was found to be reversed in leaves of GE-1437 indicating that in GE-3885, most of the nitrate might be reduced in the roots but assimilated in leaves and vice-versa. Furthermore, compared with the low-protein genotype, expression of HNRT2 was strongly induced in both roots and shoots of high-protein genotype at the least nitrate concentration supplied. This further indicates that GE-3885 is a quick sensor of nitrogen compared with the low-protein genotype. Furthermore, expression of EcDof1 was also found to overlap the expression of NR, GS, and GOGAT indicating that Dof1 probably regulates the expression of these genes under different conditions by sensing the nitrogen fluctuations around the root zone.


Assuntos
Eleusine/genética , Eleusine/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Nitratos/metabolismo , Nitrogênio/metabolismo , Transdução de Sinais/genética , Mapeamento Cromossômico , Eleusine/efeitos dos fármacos , Eleusine/enzimologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Genótipo , Glutamato Sintase/genética , Glutamato Sintase/metabolismo , Anotação de Sequência Molecular , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Nitrogênio/farmacologia , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Mol Biol Rep ; 39(8): 8035-44, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22531935

RESUMO

Two aromatic rice genotypes, Pusa Basmati 1 (PB1) and Kalanamak 3119 (KN3119) having 120 and 30 kg/ha optimum nitrogen requirement respectively, to produce optimal yield, were chosen to understand their differential nitrogen responsiveness. Both the genotypes grown under increasing nitrogen inputs showed differences in seed/panicle, 1,000 seed weight, %nitrogen in the biomass and protein content in the seeds. All these parameters in PB1 were found to be in the increasing order in contrast to KN3119 which showed declined response on increasing nitrogen dose exceeding the normal dose indicating that both the genotypes respond differentially to the nitrogen inputs. Gene expression analysis of members of ammonium transporter gene family in flag leaves during active grain filling stage revealed that all the three members of OsAMT3 family genes (OsAMT1;1-3), only one member of OsAMT2 family i.e., OsAMT2;3 and the high affinity OsAMT1;1 were differentially expressed and were affected by different doses of nitrogen. In both the genotypes, both increase and decline in seed protein contents matched with the expressions levels of OsAMT1;1, OsGS1;1 and OsGS1;2 in the flag leaves during grain filling stage indicating that high nitrogen nutrition in KN3119 probably causes the repression of these genes which might be important during grain filling.


Assuntos
Proteínas de Transporte de Cátions/genética , Genótipo , Glutamato-Amônia Ligase/genética , Nitrogênio/farmacologia , Oryza/efeitos dos fármacos , Oryza/genética , Proteínas de Plantas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glutamato-Amônia Ligase/metabolismo , Nitrogênio/metabolismo , Oryza/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Sementes/efeitos dos fármacos , Sementes/metabolismo
18.
NDT Plus ; 3(3): 326-327, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28657054
19.
Rev Sci Instrum ; 80(1): 016106, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19191467

RESUMO

A simplified design method has been proposed for systematic design of novel radio frequency (rf) power combiner and divider, incorporating radial slab-line structure, without using isolation resistor and external tuning mechanism. Due to low insertion loss, high power capability, and rigid mechanical configuration, this structure is advantageous for modern solid state rf power source used for feeding rf energy to superconducting accelerating structures. Analysis, based on equivalent circuit and radial transmission line approximation, provides simple design formula for calculating combiner parameters. Based on this method, novel 8-way and 16-way power combiners, with power handling capability of 4 kW, have been designed, as part of high power solid state rf amplifier development. Detailed experiments showed good performance in accordance with theory.

20.
Rev Sci Instrum ; 79(1): 014702, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18248055

RESUMO

A 1.5 kW solid state rf amplifier at 352 MHz has been developed and tested at RRCAT. This rf source for cw operation will be used as a part of rf system of 100 MeV proton linear accelerator. A rf power of 1.5 kW has been achieved by combining output power from eight 220 W rf amplifier modules. Amplifier modules, eight-way power combiner and divider, and directional coupler were designed indigenously for this development. High efficiency, ease of fabrication, and low cost are the main features of this design.

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