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1.
BMC Plant Biol ; 24(1): 572, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890574

RESUMEN

BACKGROUND: Nitrogen (N) availability is crucial in regulating plants' abiotic stress resistance, particularly at the seedling stage. Nevertheless, plant responses to N under salinity conditions may vary depending on the soil's NH4+ to NO3- ratio. METHODS: In this study, we investigated the effects of different NH4+:NO3- ratios (100/0, 0/100, 25/75, 50/50, and 75/25) on the growth and physio-biochemical responses of soybean seedlings grown under controlled and saline stress conditions (0-, 50-, and 100-mM L- 1 NaCl and Na2SO4, at a 1:1 molar ratio). RESULTS: We observed that shoot length, root length, and leaf-stem-root dry weight decreased significantly with increased saline stress levels compared to control. Moreover, there was a significant accumulation of Na+, Cl-, hydrogen peroxide (H2O2), and malondialdehyde (MDA) but impaired ascorbate-glutathione pools (AsA-GSH). They also displayed lower photosynthetic pigments (chlorophyll-a and chlorophyll-b), K+ ion, K+/Na+ ratio, and weakened O2•--H2O2-scavenging enzymes such as superoxide dismutase, catalase, peroxidase, monodehydroascorbate reductase, glutathione reductase under both saline stress levels, while reduced ascorbate peroxidase, and dehydroascorbate reductase under 100-mM stress, demonstrating their sensitivity to a saline environment. Moreover, the concentrations of proline, glycine betaine, total phenolic, flavonoids, and abscisic acid increased under both stresses compared to the control. They also exhibited lower indole acetic acid, gibberellic acid, cytokinins, and zeatine riboside, which may account for their reduced biomass. However, NH4+:NO3- ratios caused a differential response to alleviate saline stress toxicity. Soybean seedlings supplemented with optimal ratios of NH4+:NO3- (T3 = 25:75 and T = 4 50:50) displayed lower Na+ and Cl- and ABA but improved K+ and K+/Na+, pigments, growth hormones, and biomass compared to higher NH4+:NO3- ratios. They also exhibited higher O2•--H2O2-scavenging enzymes and optimized H2O2, MDA, and AsA-GSH pools status in favor of the higher biomass of seedlings. CONCLUSIONS: In summary, the NH4+ and NO3- ratios followed the order of 50:50 > 25:75 > 0:100 > 75:25 > 100:0 for regulating the morpho-physio-biochemical responses in seedlings under SS conditions. Accordingly, we suggest that applying optimal ratios of NH4+ and NO3- (25/75 and 50:50) can improve the resistance of soybean seedlings grown in saline conditions.


Asunto(s)
Antioxidantes , Glycine max , Nitratos , Reguladores del Crecimiento de las Plantas , Tolerancia a la Sal , Plantones , Glycine max/fisiología , Glycine max/efectos de los fármacos , Glycine max/metabolismo , Glycine max/crecimiento & desarrollo , Plantones/fisiología , Plantones/efectos de los fármacos , Plantones/metabolismo , Plantones/crecimiento & desarrollo , Antioxidantes/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Nitratos/metabolismo , Compuestos de Amonio/metabolismo , Estrés Salino , Iones/metabolismo
2.
BMC Cancer ; 17(1): 694, 2017 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-29061136

RESUMEN

BACKGROUND: The emergence of chemoresistant cancers and toxicity related to existing chemotherapeutic agents, demand the search for new pharmacophore with enhanced anti-cancer activity and least toxicity. For this purpose, three new sesquiterpenes were isolated from ethyl acetate fraction of the aerial parts of the plant Polygonum barbatum and evaluated for their anti-cancer potential. METHODS: The structural elucidation and characterization of the isolated compounds 1-3 were performed using various spectroscopic techniques such as mass, UV, IR, and extensive 1D/2D-NMR spectroscopy. Furthermore, the compounds 1-3 were subjected to screening of anti-cancer activity against different cell lines followed by brief analysis of apoptotic and anti-angiogenic potentials of the potent hit against non-small cell lung carcinoma cell line. RESULTS: All the compounds 1-3 were subjected to anti-proliferative potential against non-small cell lung carcinoma (NCI-H460), breast cancer (MCF-7), cervical cancer (HeLa) and normal mouse fibroblast (NIH-3 T3) cell lines. Among these, compound 3 was found to be more cytotoxic against NCI-H460 and MCF-7 cells (IC50 = 17.86 ± 0.72 and 11.86 ± 0.46 µM respectively). When compared with the standard drug cisplatin compound 3 was found to have more potent activity against NCI-H460 (IC50 = 19 ± 1.24 µM) as compared to MCF-7 cell lines (IC50 = 9.62 ± 0.5 µM). Compound 3 induced apoptosis in NCI-H460 cells in a dose dependent manner. It significantly downregulated, the expression of anti-apoptotic (BCL-2 L1 and p53) and increased the expression of pro-apoptotic (BAK and BAX) genes. Besides apoptosis, it also significantly reduced the cell migration and downregulated the angiogenic genes (i.e. VEGF and COX-2), thereby, inhibiting angiogenesis in NCI-H460 cells. CONCLUSION: Compound 3 possesses potent anti-proliferative potential as well as induced apoptosis and inhibited the cell migration of the cancerous cells by altering the gene expression, responsible for it.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Polygonum/química , Sesquiterpenos/farmacología , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Células HeLa , Humanos , Células MCF-7 , Ratones , Células 3T3 NIH , Neoplasias/fisiopatología
3.
New Phytol ; 209(3): 1040-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26474307

RESUMEN

Potassium (K(+) ) is the most important cationic nutrient for all living organisms. Vacuolar two-pore K(+) (TPK) channels are important players in the regulation of cellular levels of K(+) but have not been characterised in rice. In order to assess the role of OsTPKb, a K(+) selective ion channel predominantly expressed in the tonoplast of small vacuoles, we generated overexpressing (OX) lines using a constitutive promoter and compared their phenotypes with control plants. Relative to control plants, OX lines showed better growth when exposed to low-K(+) or water stress conditions. K(+) uptake was greater in OX lines which may be driven by increased AKT1 and HAK1 activity. The enhanced K(+) uptake led to tissue K(+) levels that were raised in roots and shoots. Furthermore, energy dispersive X-ray (EDX) analyses showed a higher cytoplasm: vacuole K(+) ratio which is likely to contribute to the increased stress tolerance. In all, the data suggest that TPKb can alter the K(+) status of small vacuoles, which is important for general cellular K(+) homeostasis which, in turn, affects stress tolerance.


Asunto(s)
Adaptación Fisiológica , Sequías , Oryza/metabolismo , Ósmosis , Proteínas de Plantas/metabolismo , Canales de Potasio/metabolismo , Vacuolas/metabolismo , Adaptación Fisiológica/genética , Regulación de la Expresión Génica de las Plantas , Hidroponía , Oryza/genética , Oryza/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Potasio/metabolismo , Canales de Potasio/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría por Rayos X , Estrés Fisiológico/genética , Agua
4.
J Exp Bot ; 67(9): 2689-98, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-26969743

RESUMEN

Potassium (K(+)) is the most important cationic nutrient for all living organisms and has roles in most aspects of plant physiology. To assess the impact of one of the main K(+) uptake components, the K(+) inward rectifying channel AKT1, we characterized both loss of function and overexpression of OsAKT1 in rice. In many conditions, AKT1 expression correlated with K(+) uptake and tissue K(+) levels. No salinity-related growth phenotype was observed for either loss or gain of function mutants. However, a correlation between AKT1 expression and root Na(+) when the external Na/K ratio was high suggests that there may be a role for AKT1 in Na(+) uptake in such conditions. In contrast to findings with Arabidopsis thaliana, we did not detect any change in growth of AKT1 loss of function mutants in the presence of NH4 (+) Nevertheless, NH4 (+)-dependent inhibition was detected during K(+) uptake assays in loss of function and wild type plants, depending on pre-growth conditions. The most prominent result of OsAKT1 overexpression was a reduction in sensitivity to osmotic/drought stress in transgenic plants: the data suggest that AKT1 overexpression improved rice osmotic and drought stress tolerance by increasing tissue levels of K(+), especially in the root.


Asunto(s)
Oryza/fisiología , Proteínas de Plantas/metabolismo , Canales de Potasio/metabolismo , Deshidratación , Oryza/metabolismo , Proteínas de Plantas/fisiología , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Plantas Modificadas Genéticamente , Potasio/metabolismo , Canales de Potasio/fisiología
5.
Pak J Pharm Sci ; 29(5 Suppl): 1787-1794, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28476703

RESUMEN

The present study aimed to quantify the total phenolic content in Paeonia emodi rhizome methanol extract and its fractions and then evaluate the in vitro antioxidant and hepatoprotective activities of fractions rich in phenolic compounds. Maximum quantity of total phenolic content was observed in butanol (112.08±5.5 mg GAE/g dw) and chloroform fraction (107.0±3.5 mg GAE/g dw) followed by methanol extract (94.2±4.4 mg GAE/g dw), aqueous fraction (92.9±2.5 mg GAE/g dw), ethyl acetate (62.3±8.3 mg GAE/g dw) and n-hexane fraction (51.6±7.2 mg GAE/g dw). The fractions rich in total phenolic content were evaluated for in vitro antioxidant activity based on 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) scavenging assay. The butanol and chloroform fraction showed significantly (P<0.05) higher radical scavenging activity with IC50 values of 6.5 and 7.05±2.5 ppm respectively. Positive correlation (R square=0.95) was observed between total phenolic content and in vitro antioxidant activity. The fractions rich in phenolic compounds were also evaluated for their hepatoprotective activity in paracetamol intoxicated mice. Five days oral administration of these fractions at a dose of 300 mg/kg body weight restored the serum ALT, AST and ALP levels of paracetamol intoxicated mice to normal level. From the results of the present research it was concluded that the butanol and chloroform fractions of P. emodi rhizome methanol extract are rich in phenolic compounds and strong antioxidant and effective in attenuation of hepatotoxicity.


Asunto(s)
Antioxidantes/farmacología , Hígado/efectos de los fármacos , Paeonia/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Rizoma/química , Animales , Concentración 50 Inhibidora , Masculino , Metanol/química , Ratones , Fenoles/análisis
6.
Ecotoxicology ; 24(6): 1259-68, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26070715

RESUMEN

The roles of different concentrations of arsenite (As(III)) and cadmium (Cd) (0, 25 and 50 µM) in the absence and presence (1.7 mM) of phosphate (P) in tolerance and antioxidant genes expression in Oryza sativa L. were investigated. The growth parameters, metal accumulation, lipid peroxidation and soluble protein and 17 genes involved in metal accumulation and oxidative stress were measured. In our results, Lsi6 (OsNIP2;2) could play an important role in As(III) accumulation of shoots and roots in P supply (+P) and deficiency (-P) plant, while OsNRAMP5 was attributed to the part of As(III) uptake though roots under -P condition. Both of Lsi6 and OsNRAMP5 could involve Cd uptake of roots in +P plant. OsNRAMP1 was a main transporter for As(III) and Cd uptake in roots of -P plant. However, +P increased the soluble protein contents and reduced the lipid peroxidation under As(III) or Cd exposures. In As(III) exposed rice seedlings, SOD, CAT, POD, GPX, AsA-GSH cycle and GSH metabolism process were provoked to eliminate ROS induced by As(III), especially under -P condition. In Cd exposed rice seedlings, AsA-GSH cycle and GSH metabolism process played a main role in the detoxification process of plant cells, and +P could promote enzyme system activity. Furthermore, +P improve the tolerance ability of plants to tolerant 50 µM As(III) and Cd exposures compared to P deficiency.


Asunto(s)
Arsenitos/toxicidad , Cadmio/toxicidad , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Oryza/genética , Fosfatos/metabolismo , Antioxidantes/metabolismo , Oryza/efectos de los fármacos , Oryza/metabolismo , Estrés Oxidativo/efectos de los fármacos , Plantones/efectos de los fármacos , Plantones/genética , Plantones/metabolismo
7.
Chemosphere ; 351: 141272, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38262491

RESUMEN

Herein, a coordination polymer gel is proposed for the determination of As(III) in real samples through multispectroscopic techniques viz. spectrophotometry, spectrofluorimetry, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Taguchi L32 (46 21) design and adaptive neuro fuzzy inference system (ANFIS) optimized the controllable factors affecting the extraction yielding an experimental S/N ratio of 39.94 dB. The fluorescence quenching (KSV = 2.63 × 106 L mol-1) was static with photoelectron transfer being the main mechanism confirmed by the density functional theory calculations. The limits of detection (LODs), limits of quantification (LOQs) and linear ranges were 0.038 µg L-1, 0.13 µg L-1 and 1.67-116.67 µg L-1, 0.40 µg L-1, 1.21 µg L-1 and 1.67-33.33 µg L-1, 1.07 µg L-1, 3.24 µg L-1 and 3.32-35.37 µg L-1 for the developed enrichment coupled ICP-AES, spectrophotometry and fluorescence sensing methods. Among these methods, the enrichment - ICP-AES method has the lowest LOD, LOQ and the widest linear range followed by the enrichment - spectrophotometry and fluorescene sensing methods. Spectrofluorimetry offers high sensitivity, selectivity, and possible real time monitoring, spectrophotometry provides a cost-effective and versatile option, while ICP-AES manifests multi-element analysis with high sensitivity and low interference. The developed methods were validated and employed for the successful determination of trace As(III) in real samples. The employment of these methods enhances the overall analytical capability for a wide range of sample types and concentrations.


Asunto(s)
Oligoelementos , Espectrofotometría Atómica/métodos , Oligoelementos/análisis , Agua , Espectrometría de Fluorescencia , Límite de Detección
8.
Cureus ; 16(5): e60747, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38903296

RESUMEN

Background Surgical excision is the primary treatment for juvenile nasopharyngeal angiofibroma (JNA), but this procedure is challenging due to its high vascularity and local aggressiveness. Moreover, preoperative embolization is a subject of debate. Objective The objective of this study is to assess the efficacy, safety, and feasibility of endoscope-assisted excision as a surgical intervention for non-embolized advanced JNA. Materials and methods This case series involved six male patients (mean age: 16 years) with JNA, classified as stages Ⅱc to Ⅲb according to the Radkowski classification. None underwent preoperative embolization. Results Two stage Ⅱc cases underwent total endoscopic endonasal excision. One patient with stage Ⅲa and another with stage Ⅲb underwent surgery via an endoscope-assisted sublabial approach. Two patients, one with stage Ⅱc JNA and another with Ⅲb, underwent a two-stage procedure. Postoperative CT scans showed no residual disease at the six-month mark. On average, each procedure required 1.5 units of blood transfusion. One patient experienced intraoperative bleeding, whereas the remaining patients were free of any major complications. The mean operation duration was 175 minutes per procedure. The mean length of stay at the hospital was 3.75 days per procedure. Conclusion Endoscope-assisted or purely endoscopic approaches can be safely and effectively employed for the complete excision of non-embolized advanced JNAs.

9.
Pak J Pharm Sci ; 26(5): 949-52, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24035951

RESUMEN

The present research investigation was aimed at the evaluation of antioxidant activities of methanolic (70%) extracts of whole plant of Pentanema vestitum and fruits of Pistacia integerrima, Withiana somniferra and Withiana coagulans on scavenging of 2, 2-diphenyl-2-picrylhydrazyl (DPPH) free radical. The rank of order of free antioxidant activity of the selected plants was; P. integerrima > P. vestitum > W. somniferra > W. coagulans as compared to standard Ascorbic acid. P. integerrima showed significantly higher activity at all concentrations as compared to Ascorbic acid at P<0.05. The percent inhibition caused by P. integerrima at lowest concentration (40 ppm) was 68.16±0.5 and that of Ascorbic acid was 62.00±0.5. The IC50 value of P. integerrima was 5.75ppm as compared to ascorbic acid having 15.09 ppm. The percent inhibition at all concentrations caused by P. vestitum was not significantly different from Ascorbic acid at P<0.05. The IC50 value of P. vestitum was 13.00ppm and that of Ascorbic acid was 15.09 ppm. The percent inhibitions caused by W. somniferra (IC50=46.85 ppm) and W. coagulans (IC50=84.40 ppm) were most significantly lower than Ascorbic acid at P<0.05. It is inferred from the current study that the methanolic (70%) extracts of the P. integerrima and P. vestitum could be used in preparation of potent antioxidant drugs.


Asunto(s)
Asteraceae , Compuestos de Bifenilo/química , Depuradores de Radicales Libres/química , Picratos/química , Pistacia , Preparaciones de Plantas/química , Solanaceae , Asteraceae/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Frutas , Metanol/química , Fitoterapia , Pistacia/química , Preparaciones de Plantas/aislamiento & purificación , Preparaciones de Plantas/farmacología , Plantas Medicinales , Solanaceae/química , Solventes/química
10.
J Hazard Mater ; 457: 131783, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37327609

RESUMEN

A novel coordination polymer gel based on zirconium(IV) and 2-thiobarbituric (ZrTBA) was synthesized and explored its potential to remediate As(III) from water. Box-Behnken design with desirability function and genetic algorithm yielded the optimized conditions (initial concentration=194 mg L-1, dosage = 42.2 mg, time= 95 min and pH = 4.9) for maximum removal efficiency (99.19 %). The experimental saturation capacity for As(III) was 178.30 mg g-1. The steric parameter n > 1 of the best fitted statistical physics model: monolayer with two energies (R2 = 0.987-0.992) suggested multimolecular mechanism with vertical orientation of As(III) molecules onto the two active sites. XPS and FTIR confirmed the two active sites being zirconium and oxygen. The adsorption energies (E1 = 35.81-37.63 kJ/mol; E2 = 29.50-36.49 kJ/mol) and isosteric heat of adsorption indicated that physical forces governed the As(III) uptake. DFT calculations implied that the weak electrostatic interaction and hydrogen bonding were involved. The best fitted (R2>0.99) fractal like pseudo first order model established energetic heterogeneity. ZrTBA showed excellent removal efficiency in the presence of potential interfering ions and could be used up to 5 cycles of adsorption-desorption with < 8 % loss in the efficiency. ZrTBA removed ≥96.06 % As(III) from real water samples spiked at different levels of As(III).

11.
Opt Express ; 20(4): 3443-55, 2012 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-22418103

RESUMEN

In an optically synchronized short-pulse optical-parametric chirped-pulse amplification (OPCPA) system, we observe a few-100 fs-scale timing jitter. With an active timing stabilization system slow fluctuations are removed and the timing jitter can be reduced to 100 fs standard deviation (Std). As the main source for the timing fluctuations we could identify air turbulence in the stretcher-compressor setup inside the chirped pulse amplification (CPA) pump chain. This observation is supported by theoretical investigation of group delay changes for angular deviations occurring between the parallel gratings of a compressor or stretcher, as they can be introduced by air turbulence.

12.
Opt Express ; 20(4): 4619-29, 2012 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-22418219

RESUMEN

On the quest towards reaching petawatt-scale peak power light pulses with few-cycle duration, optical parametric chirped pulse amplification (OPCPA) pumped on a time scale of a few picoseconds represents a very promising route. Here we present an experimental demonstration of few-ps OPCPA in DKDP, in order to experimentally verify the feasibility of the scheme. Broadband amplification was observed in the wavelength range of 830-1310 nm. The amplified spectrum supports two optical cycle pulses, at a central wavelength of ~920 nm, with a pulse duration of 6.1 fs (FWHM). The comparison of the experimental results with our numerical calculations of the OPCPA process showed good agreement. These findings confirm the reliability of our theoretical modelling, in particular with respect to the design for further amplification stages, scaling the output peak powers to the petawatt scale.

13.
Ann Oper Res ; : 1-24, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36091932

RESUMEN

The thought to put forward a queuing model proposed in this work was its pertinence in everyday life wherever we can see the uses of computing and networking systems. Industrial software developers and system managers can consider the results of the model to evolve their system for better results. Here we present a novel queueing model having erratic server with delayed repair and balking. Two distinct breakdowns i.e. active and passive breakdown for the system are also considered with their respective amendments. This model is closely related with the smooth functioning of the system during some internal faults (virus attack, electricity failures etc.). The performance indicators which are utilized in enhancing the service standards are obtained using supplementary variable technique. Using ANFIS soft computing technique we have compared the analytical results with those of neuro fuzzy results. Furthermore single and bi-objective minimization problems are considered and minima is obtained using particle swarm optimization and multi objective genetic algorithm respectively. Also, the minimization problems are shown as a convex programming problem to ensure the global optimality of the result. The proposed approach makes it conceivable to accomplish a relevant harmony between operational expenses and administration quality.

14.
Plants (Basel) ; 11(5)2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35270123

RESUMEN

Jasmonates (JAs) are lipid-derived compounds that function in plants as key signaling compounds during stressful conditions. This study aimed to examine the effects of exogenous fo-liar-JA application (100 µmol L-1) on the morpho-physiological response of two soybean varieties (parachinar-local and swat-84) grown under different NaCl regimes (0, 40, 80, and 120 mM). Results show that exogenous JA application alone and in combination with salt stress altered the growth and metabolism of both soybeans. For instance, they accumulated significant amounts of Na+ and Cl-, while their K+, Mg2+, Fe2+, Mn2+, B3+, and P3+ contents were low. Further, photosynthetic pigments Chl a and Chl b increased at low concentrations of salt and exogenous JA. Car decreased under both salt and exogenous JA as compared with untreated control. In addition, sugar, phenol, and protein content increased under both salt and exogenous JA application. In contrast, the exogenous JA application alleviated the negative impact of salt stress on the growth and metabolism of both soybeans. Further, the high concentrations of soluble protein and phenol in the leaves of both soybeans may contribute to their ability to adapt to salinity. However, molecular studies are necessary to understand the ameliorative role of exogenous JA in the growth and metabolism of salt-treated young seedlings in both soybean varieties.

15.
Rev Sci Instrum ; 93(11): 113311, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36461536

RESUMEN

The absolute response of a real-time proton detector, composed of a microchannel plate (MCP) assembly, an imaging lens, and a charge-coupled device (CCD) camera, is calibrated for the spectral characterization of laser-accelerated protons, using a Thomson parabola spectrometer (TPS). A slotted CR-39 plate was used as an absolute particle-counting detector in the TPS, simultaneously with the MCP-CCD detector to obtain a calibration factor (count/proton). In order to obtain the calibration factor as a function of proton energy for a wide range of proton numbers, the absolute response was investigated for different operation parameters of the MCP-CCD detector, such as MCP voltage, phosphor voltage, and CCD gain. A theoretical calculation for the net response of the MCP was in good agreement with the calibrated response of the MCP-CCD detector, and allows us to extend the response to higher proton energies. The response varies in two orders of magnitude, showing an exponential increase with the MCP voltage and almost linear increase with the phosphor voltage and the CCD gain. The calibrated detector enabled characterization of a proton energy spectrum in a wide dynamic range of proton numbers. Moreover, two MCP assemblies having different structures of MCP, phosphor screen, and optical output window have been calibrated, and the difference in the absolute response was highlighted. The highly-sensitive detector operated with maximum values of the parameters enables measuring a single proton particle and evaluating an absolute spectrum at high proton energies in a single laser shot. The absolute calibrations can be applied for the spectral measurement of protons using different operating voltages and gains for optimized response in a large range of proton energy and number.

16.
Opt Express ; 19(6): 5357-63, 2011 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-21445174

RESUMEN

We present a chirped pulse amplification (CPA) system based on diode-pumped Yb:YAG. The stretched ns-pulses are amplified and have been compressed to less than 900 fs with an energy of 200 mJ and a repetition rate of 10 Hz. This system is optically synchronized with a broadband seed laser and therefore ideally suited for pumping optical parametric chirped pulse amplification (OPCPA) stages on a ps-timescale.

17.
Drug Metab Pers Ther ; 36(3): 247-250, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33770821

RESUMEN

OBJECTIVES: Pain in joints is a major clinical problem since ancient times. Waja-uz-Zahr stands for low back pain which may arise from internal or external structures of lumbosacral region due to Su-e-Mizaj sada or maddi due to the surplus of Burudat or accumulation of Kham Balgham in lower back. Imala (diversion) and Taqiya-e-Mavad (Evacuation) are inevitable in case of maddi amraz. Hijama (cupping therapy) is a simple, safe, tolerable, and effective regimenal modality, helpful in the treatment of aches and pains. Gruner mentioned a special kind of cupping method in the canon of medicine of Avicenna where cupping glasses are glided over a specified area of body intending the diversion of morbid material under the name of Bier's treatment. The purpose of present case series was to provide the insight into the effect of gliding cupping in low back ache. CASE PRESENTATION: Three patients of Waja-uz-Zahr, aged between 29 and 64 years, were given gliding cupping treatment after the application of Roghan-e-Surkh on lumbosacral region alternatively for 14 days. Oswestry disability index (ODI) and visual analogue scale (VAS) were used for the assessment of efficacy. Improvement, in case 1, case 2, and case 3 in ODI score was 42.42, 68.18, and 62.50%, respectively while in VAS score, it was 50, 62.5, and 50%, respectively, was observed without any adverse effect. CONCLUSIONS: On the basis of the above results, it can be concluded that the gliding cupping therapy may be used as an effective modality of treatment for low back ache.


Asunto(s)
Dolor de la Región Lumbar , Adulto , Humanos , Dolor de la Región Lumbar/terapia , Persona de Mediana Edad , Dimensión del Dolor , Proyectos de Investigación
18.
Artículo en Inglés | MEDLINE | ID: mdl-32727342

RESUMEN

Nature has the potential to reduce metal salts to their relative nanoparticles. Traditionally, physical and chemical methods were used for the synthesis of nanoparticles but due to the use of toxic chemicals, non-ecofriendly methods and other harmful effects, green chemistry approaches are now employed for synthesizing nanoparticles which are basically the most cost effective, ecofriendly and non-hazardous methods. In this review, we aimed to evaluate and study the details of various mechanisms used for green synthesis of silver nanoparticles from plants, their size, shape and potential applications. A total of 150 articles comprising both research and review articles from 2009 to 2019 were selected and studied in detail to get in-depth knowledge about the synthesis of silver nanoparticles specifically through green chemistry approaches. Silver ions and their salts are well known for their antimicrobial properties and have been used in various medical and non-medical applications since the emergence of human civilization. Miscellaneous attempts have been made to synthesize nanoparticles using plants and such nanoparticles are more efficient and beneficial in terms of their antibacterial, antifungal, antioxidant, anti-biofilm and cytotoxic activities than nanoparticles synthesized through physical and chemical processes. Silver nanoparticles have been studied as an important research area due to their specific and tunable properties and their application in the field of biomedicine such as tissue and tumor imaging and drug delivery. These nanoparticles can be further investigated to find out their antimicrobial potential in cell lines and animal models.


Asunto(s)
Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Extractos Vegetales/síntesis química , Estructuras de las Plantas/química , Plata/química , Animales , Antibacterianos/síntesis química , Antioxidantes/síntesis química , Tecnología Química Verde/tendencias , Humanos , Extractos Vegetales/aislamiento & purificación
19.
Food Chem ; 334: 127563, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32791433

RESUMEN

A new magnetic Cu(II) IIP (Fe3O4@IIP-IDC) is synthesized by polymerization of Imidazole-4,5-dicarboxylic acid functionalized Allyl chloride, and significant improvement of its performance has been compared. SPE parameters were optimized using Box-Behnken design to achieve the twin objectives of quantitative determination and removal of Cu(II). FLPSO kinetic model and BS isotherm model fits well with the capacity of 175 mg g-1. Analytical figures of merit includes a linearity range of 10-5,000 µg L-1 (R2 = 0.9986), preconcentration factor of 50 after eluting with 5 mL of 1 M HNO3, LOD of 1.03 µg L-1 and LOQ of 4.5 µg L-1. Accuracy was assessed by analysis of SRM (Standard Reference Material) and recovery experiments after spiking in food samples (Tea, coffee, chocolate, spinach, infant milk substitute) and battery wastewater. Ease of use, reusability (15 cycles), rapid adsorption and high selectivity makes it a promising candidate for efficient and selective removal and trace determination.


Asunto(s)
Cobre/análisis , Análisis de los Alimentos/métodos , Impresión Molecular/métodos , Polímeros/química , Contaminantes Químicos del Agua/análisis , Adsorción , Compuestos Alílicos/química , Cobre/aislamiento & purificación , Ácidos Dicarboxílicos/química , Análisis de los Alimentos/instrumentación , Contaminación de Alimentos/análisis , Imidazoles/química , Límite de Detección , Fenómenos Magnéticos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
20.
Rev Sci Instrum ; 92(2): 023302, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33648087

RESUMEN

We present a proof of principle for onsite calibration of a radiochromic film (EBT3) using CR-39 as an absolute proton-counting detector and laser-accelerated protons as a calibration source. A special detector assembly composed of aluminum range filters, an EBT3 film, and a CR-39 detector is used to expose the EBT3 film with protons in an energy range of 3.65 MeV-5.85 MeV. In our design, the proton beam is divided into small beamlets and their projection images are taken on the EBT3 film and the CR-39 detector by maintaining a certain distance between the two detectors. Owing to the geometrical factor of the configuration and scattering inside the EBT3, the areal number density of protons was kept below the saturation level of the CR-39 detector. We also present a method to relate the number of protons detected on the CR-39 in a narrow energy range to protons with a broad energy spectrum that contribute to the dose deposited in the EBT3 film. The energy spectrum of protons emitted along the target normal direction is simultaneously measured using another CR-39 detector installed in a Thomson parabola spectrometer. The calibration curves for the EBT3 film were obtained in the optical density range of 0.01-0.25 for low dose values of 0.1 Gy-3.0 Gy. Our results are in good agreement with the calibrations of the EBT3 film that are traditionally carried out using conventional accelerators. The method presented here can be further extended for onsite calibration of radiochromic films of other types and for a higher range of dose values.

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