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1.
Small ; 20(20): e2307956, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38143295

RESUMEN

A cross-comparison of three stop-flow configurations-such as low-pressure (LSF), high-pressure open-circuit (OC-HSF), and high-pressure short-circuit (SC-HSF) stop-flow-is presented to rapidly bring a high velocity flow O(m s-1) within a microchannel to a standstill O(µm s-1). The performance of three stop-flow configurations is assessed by measuring residual flow velocities within microchannels having three orders of magnitude different flow resistances. The LSF configuration outperforms the OC-HSF and SC-HSF configurations within a high flow resistance microchannel and results in a residual velocity of <10 µm s-1. The OC-HSF configuration results in a residual velocity of <150 µm s-1 within a low flow resistance microchannel. The SC-HSF configuration results in a residual velocity of <200 µm s-1 across the three orders-of-magnitude different flow resistance microchannels, and <100 µm s-1 for the low flow resistance channel. It is hypothesized that residual velocity results from compliance in fluidic circuits, which is further investigated by varying the elasticity of microchannel walls and connecting tubing. A numerical model is developed to estimate the expanded volumes of the compliant microchannel and connecting tubings under a pressure gradient and to calculate the distance traveled by the sample fluid. A comparison of the numerically and experimentally obtained traveling distances confirms the hypothesis that the residual velocities are an outcome of the compliance in the fluidic circuit.

2.
Int J Phytoremediation ; 26(3): 349-368, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37559458

RESUMEN

Wastewater contamination with heavy metal(loids)s has become a worldwide environmental and public health problem due to their toxic and non-degradable nature. Different methods and technologies have been applied for water/wastewater treatment to mitigate heavy metal(loid)-induced toxicity threat to humans. Among various treatment methods, adsorption is considered the most attractive method because of its high ability and efficiency to remove contaminants from wastewater. Agricultural waste-based adsorbents have gained great attention because of high efficiency to heavy metal(loids)s removal from contaminated water. Chemically modified biosorbents can significantly enhance the stability and adsorption ability of the sorbents. The two mathematical models of sorption, Freundlich and Langmuir isotherm models, have mostly been studied. In kinetic modeling, pseudo-second-order model proved better in most of the studies compared to pseudo-first-order model. The ion exchange and electrostatic attraction are the main mechanisms for adsorption of heavy metal(loid)s on biosorbents. The regeneration has allowed various biosorbents to be recycled and reused up to 4-5 time. Most effective eluents used for regeneration are dilute acids. For practical perspective, biosorbent removal efficiency has been elucidated using various types of wastewater and economic analysis studies. Economic analysis of adsorption process using agricultural waste-based biosorbents proved this approach cheaper compared to traditional commercial adsorbents, such as chemically activated carbon. The review also highlights key research gaps to advance the scope and application of waste peels for the remediation of heavy metal(loid)s-contaminated wastewater.


This review provides new information and insights on the potential utilization of agriculture-based biosorbents for the removal of contaminants, especially heavy metal(loid)s from toxic water/wastewater, as well as their mechanisms, adsorption efficiency, and regeneration ability. For practical perspective, biosorbent adsorption efficiency was elucidated by using various types of wastewater and economic analysis studies.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Humanos , Aguas Residuales , Biodegradación Ambiental , Modelos Teóricos , Adsorción , Cinética , Agua
3.
Pak J Med Sci ; 40(2ICON Suppl): S97-S99, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38328648

RESUMEN

Primary Giant Cell Tumor of Soft Tissue (GCT-ST) is a rare disease, a neoplasm with low potential for malignancy. It belongs to the group of Fibrohistiocytic tumors with borderline malignancy. Most commonly it presents as a painless, slow-growing mass in a superficial location. It is associated with lower local recurrence rate as compared to GCT of bone but has a higher rate for metastasis and mortality. A case of rare GCT-ST with suspicion of lung metastasis is being reported here. The lesion per-operatively appeared to be growing from the periosteum of the bone (tibia in our case). After excisional biopsy it proved to be GCT-ST which has never been reported previously in literature.

4.
Nano Lett ; 22(12): 4848-4853, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35675212

RESUMEN

Heterostructures of optical cavities and quantum emitters have been highlighted for enhanced light-matter interactions. A silicon nanosphere, core, and MoS2, shell, structure is one such heterostructure referred to as the core@shell architecture. However, the complexity of the synthesis and inherent difficulties to locally probe this architecture have resulted in a lack of information about its localized features limiting its advances. Here, we utilize valence electron energy loss spectroscopy (VEELS) to extract spatially resolved dielectric functions of Si@MoS2 with nanoscale spatial resolution corroborated with simulations. A hybrid electronic critical point is identified ∼3.8 eV for Si@MoS2. The dielectric functions at the Si/MoS2 interface is further probed with a cross-sectioned core-shell to assess the contribution of each component. Various optical parameters can be defined via the dielectric function. Hence, the methodology and evolution of the dielectric function herein reported provide a platform for exploring other complex photonic nanostructures.


Asunto(s)
Molibdeno , Nanoestructuras , Electrónica , Nanoestructuras/química , Silicio/química
5.
Environ Monit Assess ; 195(11): 1326, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37845569

RESUMEN

During the green revolution in the mid-twentieth century, the consumption of inorganic phosphorous and phosphate-based fertilizers (P-fertilizers) in the developing world skyrocketed, resulting in a proliferation of P-fertilizer industries. Phosphate-based fertilizer industries are ranked among the most environment-polluting industries. The worldwide phosphorus market, which was 68.5 million metric tons in 2020, is expected to increase at a compound annual growth rate (CAGR) of 2.5% to 81 million metric tons by 2027. The release of untreated hazardous pollutants from these fertilizer industries into the soil, water, and atmosphere has resulted in severe environmental health issues. Excessive surface runoff of phosphorus from agricultural fields and its deposition in water promote the growth of algae and macrophytes and lower dissolved oxygen concentration through eutrophication, which is detrimental to aquatic life. Fluorides (F-) and sulfur dioxide (SO2) and/or heavy metals (potentially toxic elements, PTEs) are also detected in the emissions from these fertilizer industries. The main solid waste generated from the phospho-gypsum plant produced up to 5 tons of di-hydrogen phosphate (H2PO4), including PTEs and radioactive substances. Phosphates and fluorenes from these industries are usually disposed of as sludge in storage ponds or trash piles. Humans inhaling poisonous gases released from the P-fertilizer industries can develop hepatic failure, autoimmune diseases, pulmonary disorders, and other health problems. The objectives of this review are to provide guidelines for eliminating the bottleneck pollutions that occur from the phosphate-based fertilizer industries and explore the management practices for its green development.


Asunto(s)
Fertilizantes , Fosfatos , Humanos , Fosfatos/análisis , Residuos Industriales/análisis , Monitoreo del Ambiente , Fósforo/análisis , Suelo , Plantas , Agua
6.
Physiol Mol Biol Plants ; 29(8): 1205-1224, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37829703

RESUMEN

Cenchrus ciliaris L. is a perennial grass that can grow in a diverse range of habitats including challenging deserts. The purpose of the study was to investigate the impact of aridity on morpho-anatomical and physiological traits in C. ciliaris populations collected from arid and semi-arid areas of Punjab, Pakistan. The populations growing in extremely arid conditions displayed a range of structural and physiological adaptations. Under extremely dry conditions, root epidermal thickness (90.29 µm), cortical cell area (7677.78 µm2), and metaxylem cell area (11,884.79 µm2) increased while root pith cell area (2681.96 µm2) decreased in tolerant populations. The populations under extremely aridity maximized leaf lamina (184.21 µm) and midrib thickness (316.46 µm). Additionally, highly tolerant populations were characterized by the accumulation of organic osmolytes such as glycinebetaine (132.60 µmol g-1 FW) was increased in QN poulations, proline (118.01 µmol g-1 F.W) was maximum in DF populations, and total amino acids (69.90 mg g-1 FW) under extreme water deficit conditions. In arid conditions, abaxial stomatal density (2630.21 µm) and stomatal area (8 per mm2) were also reduced in DF populations to check water loss through transpiration. These findings suggest that various parameters are crucial for the survival of C. ciliaris in arid environments. The main strategies used by C. ciliaris was intensive sclerification, effective retention of ions, and osmotic adjustment through proline and glycinebetaine under arid conditions. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01351-3.

7.
J Digit Imaging ; 35(2): 281-301, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35013827

RESUMEN

Hypertensive retinopathy (HR) refers to changes in the morphological diameter of the retinal vessels due to persistent high blood pressure. Early detection of such changes helps in preventing blindness or even death due to stroke. These changes can be quantified by computing the arteriovenous ratio and the tortuosity severity in the retinal vasculature. This paper presents a decision support system for detecting and grading HR using morphometric analysis of retinal vasculature, particularly measuring the arteriovenous ratio (AVR) and retinal vessel tortuosity. In the first step, the retinal blood vessels are segmented and classified as arteries and veins. Then, the width of arteries and veins is measured within the region of interest around the optic disk. Next, a new iterative method is proposed to compute the AVR from the caliber measurements of arteries and veins using Parr-Hubbard and Knudtson methods. Moreover, the retinal vessel tortuosity severity index is computed for each image using 14 tortuosity severity metrics. In the end, a hybrid decision support system is proposed for the detection and grading of HR using AVR and tortuosity severity index. Furthermore, we present a new publicly available retinal vessel morphometry (RVM) dataset to evaluate the proposed methodology. The RVM dataset contains 504 retinal images with pixel-level annotations for vessel segmentation, artery/vein classification, and optic disk localization. The image-level labels for vessel tortuosity index and HR grade are also available. The proposed methods of iterative AVR measurement, tortuosity index, and HR grading are evaluated using the new RVM dataset. The results indicate that the proposed method gives superior performance than existing methods. The presented methodology is a novel advancement in automated detection and grading of HR, which can potentially be used as a clinical decision support system.


Asunto(s)
Retinopatía Hipertensiva , Disco Óptico , Humanos , Retinopatía Hipertensiva/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Vasos Retinianos/diagnóstico por imagen
8.
Environ Geochem Health ; 44(12): 4523-4538, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35129707

RESUMEN

Globally, sewage water is considered a cheap and effective alternative source of irrigation and nutrient supplement. For example, in Faisalabad, Pakistan untreated sewage water loaded with potentially toxic elements (PTEs) is being routinely used to grow fodder crops in the peri-urban areas, where PTEs accumulate at different trophic levels and contaminate the food chain. Trophic transfer, bioaccumulation, and biomagnification of hazardous metals in food chains had toxic implications for human health. Currently, the major concern is associated with the consumption of PTEs contaminated fodder by animals and the subsequent translocation into humans via consumption of milk and meat from these animals. This study thus analyzed the concentration of Cd, Cu, Pb and Zn in sewage water, sewage irrigated soil, fodder is grown on such soils and the milk of cows and buffalos to calculate the transfer through water and fodder to animal milk. Overall, concentrations and bioaccumulation factors of Cd and Cu in buffalo milk were higher than the cow milk, whereas it was inverse for the concentration of Zn. Non-significant difference in the bioaccumulation factor for Pb in both buffalo and cow milk was observed. Calculation of the estimated daily intake indicated that there was no health risk associated with the consumption of tested milk samples. However, given the widespread exposure of infants to milk, continuous monitoring of milk quality is recommended to preclude a child's exposure to elevated levels of PTEs.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Humanos , Niño , Animales , Aguas del Alcantarillado/análisis , Bioacumulación , Metales Pesados/toxicidad , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Cadmio/análisis , Monitoreo del Ambiente , Agua , Búfalos , Plomo , Suelo , Alimentación Animal
9.
Environ Monit Assess ; 194(5): 346, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35391637

RESUMEN

Arsenic (As), a class-A human carcinogen, is ubiquitously present in the earth's crust and soil and may enter the air, water, and surface environments through different natural and anthropogenic sources. In this experiment, soil, irrigation water, and rice grains were sampled from conventional rice-growing areas of Punjab, Pakistan. Soil samples were collected from 0 to 15 cm surface soil of rice growing fields, and rice grains were collected from the same field at crop maturity. Irrigation water samples were collected from the source used to irrigate the respective rice fields. Coordinates of sampling locations were noted using a global positioning system, and a locations map was made using ArcGIS. Soil samples were digested in a microwave digester using aqua regia, and plant samples were block digested using nitric acid. Arsenic concentration was determined using an inductively coupled plasma mass spectrometer coupled with an auto-sampler and integrated samples introduction system. The mean concentration of As in rice grains, soil, and water samples was found within the safe limit set by WHO except for a sample from Narowal (148.54 µg l-1) that exceeded the irrigation water standard limit, i.e., 100 µg l-1 for irrigation water. Principal component analysis was performed to reduce the multidimensional space of variables and samples. Through the calculations of estimated daily intake, it has been revealed that the As levels measured in this study would only contribute a small amount (less than 5%) of the total recommended daily intake allowance.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Contaminantes Químicos del Agua , Arsénico/análisis , Monitoreo del Ambiente , Contaminación de Alimentos/análisis , Humanos , Pakistán , Suelo , Contaminantes del Suelo/análisis , Agua/análisis , Contaminantes Químicos del Agua/análisis
10.
Inorg Chem ; 60(22): 17268-17275, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34699195

RESUMEN

Metal chalcophosphates, M2P2Q6 (M = transition metals; Q = chalcogen), are notable among the van der Waals materials family for their potential magnetic ordering that can be tuned with an appropriate choice of the metal or chalcogen. However, there has not been a systematic investigation of the basic structural evolution in these systems with alloying of the crystal subunits due to the challenge in the diffusion process of mixing different metal cations in the octahedral sites of M2P2Q6 materials. In this work, the P2S5 flux method was used to enable the synthesis of a multilayered mixed metal thiophosphate Fe2-xCoxP2S6 (x = 0, 0.25, 1, 1.75, and 2) system. Here, we studied the structural, vibrational, and electronic fingerprints of this mixed M2P2Q6 system. Structural and elemental analyses indicate a homogeneous stoichiometry averaged through the sample over multiple layers of Fe2-xCoxP2S6 compounds. It was observed that there is a correlation between the intensity of specific phonon modes and the alloying concentration. The increasing Co alloying concentration shows direct relations to the in-plane [P2S6]4- and out-of-plane P-P dimer vibrations. Interestingly, an unusual nonlinear electronic structure dependence on the metal alloying ratio is found and confirmed by two distinct work functions within the Fe2-xCoxP2S6 system. We believe this work provides a fundamental structural framework for mixed metal thiophosphate systems, which may assist in future studies on electronic and magnetic applications of this emerging class of binary cation materials.

11.
Bioorg Chem ; 115: 105164, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34314916

RESUMEN

The over expression of aldose reductase (ALR2) in the state of hyperglycemia causes the conversion of glucose into sorbitol and initiates polyol pathway. Accumulation of sorbitol in insulin insensitive tissue like peripheral nerves, glomerulus and eyes, induces diabetic complications like neuropathy, nephropathy and retinopathy. For the treatment of diabetic complications, the inhibition of aldose reductase (ALR2) is a promising approach. A series of coumarin-based thiosemicarbazone derivatives was synthesized as potential inhibitor of aldose reductase. Compound N-(2-fluorophenyl)-2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hydrazinecarbiothioamide (3n) was found to be the most promising inhibitor of ALR2 with an IC50 in micromolar range (2.07 µM) and high selectivity, relative to ALR1. The crystal structure of ALR2 complexed with 3n explored the types of interaction pattern which further demonstrated its high affinity. Compound 3n has excellent lead-likeness, underlined by its physicochemical parameters, and can be considered as a likely prospect for further structural optimization to get a drugable molecule.


Asunto(s)
Aldehído Reductasa/antagonistas & inhibidores , Cumarinas/química , Inhibidores Enzimáticos/química , Tiosemicarbazonas/química , Aldehído Reductasa/metabolismo , Sitios de Unión , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacocinética , Semivida , Humanos , Cinética , Simulación del Acoplamiento Molecular , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Estructura Terciaria de Proteína , Relación Estructura-Actividad
12.
Bioorg Chem ; 109: 104691, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33601138

RESUMEN

Urease enzyme plays a key role in pathogenesis of gastritis and peptic ulcers. Its inhibition averts our bodies from many disorders including formation of urinary calculi. In agriculture, the high urease content causes severe environmental and hence economic problems. Due to deficiency of effective and safer drugs to tackle the aforementioned disorders, the quest for new scaffolds becomes mandatory in the field of medicinal chemistry. In this regard, we herein report a new series of N4-substituted thiosemicarbazones 3a-v as potential candidates for urease inhibition. These new N4-substituted thiosemicarbazones 3a-v of distant chemical scaffolds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR, ESI-MS and in the case of compound 3g by single crystal X-ray analysis. The compounds were evaluated for their urease inhibitory potential. All newly synthesized compounds showed significant urease inhibitions with IC50 values in range of 2.7 ± 0.320-109.2 ± 3.217 µM. Molecular docking studies were used for interactions pattern and structure-activity relationship for all compounds, which demonstrated excellent binding interactions with the active site residues, such as hydrogen bonding, π-π interactions, π-H and nickel atom coordination.


Asunto(s)
Tiosemicarbazonas/química , Tiosemicarbazonas/farmacología , Ureasa/antagonistas & inhibidores , Sitios de Unión , Diseño de Fármacos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Conformación Proteica
13.
Physiol Mol Biol Plants ; 27(5): 1073-1087, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34092951

RESUMEN

The present study involved two pot experiments to investigate the response of mung bean to the individual or combined SO4 2- and selenate application under drought stress. A marked increment in biomass and NPK accumulation was recorded in mung bean seedlings fertilized with various SO4 2- sources, except for CuSO4. Compared to other SO4 2- fertilizers, ZnSO4 application resulted in the highest increase in growth attributes and shoot nutrient content. Further, the combined S and Se application (S + Se) significantly enhanced relative water content (16%), SPAD value (72%), photosynthetic rate (80%) and activities of catalase (79%), guaiacol peroxidase (53%) and superoxide dismutase (58%) in the leaves of water-stressed mung bean plants. Consequently, the grain yield of mung bean was markedly increased by 105% under water stress conditions. Furthermore, S + Se application considerably increased the concentrations of P (47%), K (75%), S (80%), Zn (160%), and Fe (15%) in mung bean seeds under drought stress conditions. These findings indicate that S + Se application potentially increases the nutritional quality of grain legumes by stimulating photosynthetic apparatus and antioxidative machinery under water deficit conditions. Our results could provide the basis for further experiments on cross-talk between S and Se regulatory pathways to improve the nutritional quality of food crops. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-00992-6.

14.
Int J Legal Med ; 134(4): 1311-1312, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31154496

RESUMEN

In this study, the Kashmiri population was genetically screened for fifteen autosomal STRs, seventeen Y-chromosomal STRs and mitochondrial DNA control region SNPs. Autosomal STRs exhibited that D2S1338 was the most discriminatory locus with value of 0.963 whereas combine power of discrimination was 0.999999999999999. On the other hand, analysis of Y-chromosomal STRs generated 59 distinct haplotypes of which 52 were unique with haplotype diversity value of 0.99752. Mitochondrial D-loop analysis resulted that haplogroups M and U were found most prevalent with 25% each. Haplotypic data of Y-STRs was submitted to YHRD under accession number YA004153 whereas mitochondrial DNA control region (CR) sequences were submitted to EMPOP with accession number EMP00683.


Asunto(s)
Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Frecuencia de los Genes , Haplotipos , Repeticiones de Microsatélite , Femenino , Genética de Población , Humanos , Masculino , Pakistán/etnología , Filogenia
15.
Nanotechnology ; 31(19): 195701, 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31940594

RESUMEN

The high transmittance and low reflectance of monolayer hexagonal boron nitride (hBN) lead to its invisibility under white-light, causing serious troubles in the search, transfer, and fabrication of 2D material devices. In this work, we demonstrate enhancing the contrast of hBN on a transparent substrate by simulation and experimental observation, where the highest contrast is obtained by using a polymer-based interfacial layer on a polydimethylsiloxane (PDMS) substrate. The simulation result reveals that the contrast under short wavelength light is higher than that under long wavelength. To confirm this, the red-green-blue components are extracted from the optical color image. The blue component image shows an hBN flake clearly on the substrate, while the hBN flake fades on the green and red components. Moreover, the contrast on transparent substrates have only positive value, while opaque substrates cause both negative and positive contrast depending on the thickness of the interfacial layer. Thus, the high contrast (∼4.5%) of hBN on the PDMS substrate enables us to observe mono- and few-layer hBN flakes under white-light illumination by an optical microscope.

16.
Bioorg Chem ; 94: 103404, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31699392

RESUMEN

A series of new hydrazonothiazolines (3a-v) was obtained in good to excellent yields (79-96%) via cyclization of the appropriate thiosemicarbazones with phenacyl bromide. The targeted compounds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR and ESI-MS. The structure of compounds 3n and 3v was unambiguously confirmed by single crystal X-ray analysis. All compounds displayed enhanced inhibitory activity against urease enzyme with IC50 values in range of 1.73 ±â€¯1.57-27.3 ±â€¯0.655 µM when compared to standard thiourea (IC50 = 20.8 ±â€¯0.75 µM). The structure-activity relationship studies demonstrated that the activity of this series is due the central thiazole ring that interacts with nickel atoms in the active site of urease enzyme. Moreover, molecular docking studies were carried out to investigate the binding mode of all active compounds and an inactive (3u) with the active site of the urease enzyme. The docking results are in complete agreement with the experimental finding.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Hidrazonas/farmacología , Simulación del Acoplamiento Molecular , Tiazoles/farmacología , Ureasa/antagonistas & inhibidores , Canavalia/enzimología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Hidrazonas/síntesis química , Hidrazonas/química , Estructura Molecular , Relación Estructura-Actividad , Tiazoles/síntesis química , Tiazoles/química , Ureasa/metabolismo
17.
Ecotoxicol Environ Saf ; 187: 109841, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31677566

RESUMEN

Drought stress is one of the extreme effects of climate change causing large losses in production of crop plants. The risk of recurrent droughts has increased in next decades hence, the development of shot-gun, inexpensive and effective approaches is essential to ensure high yield of crops in drought-prone areas of the world. Exogenous application of nutrients such as potassium (K) has been reported to increase abiotic resistance and improve yield in crops however, knowledge regarding interaction of K with osmoprotectants like chitosan (Ct) still remains elusive. Here, we report the effects of individual or combined K (using K2SO4 as a source) or Ct application on growth, physiological processes and antioxidative defense system of sunflower under drought stress. At first, various doses of K (0, 5, 10, 15, 20, 25 g/l) and Ct (0, 0.1, 0.2, 0.3, 0.4, 0.5 g/l) were foliar applied to evaluate their role in improving plant biomass, water status and total chlorophyll in drought-induced seedlings of sunflower. The optimized K (11.48 g/l) and Ct (0.28 g/l) doses were further tested in second experiment to understand the underlying mechanisms of drought tolerance. Foliar K + Ct spray markedly enhanced the leaf gas exchange characteristics, increased proline, soluble proteins, and free amino acids, upregulated antioxidant defense system and helped to maintain plant water status in sunflower exposed to drought stress. The impact of drought stress was more pronounced at vegetative than reproductive stage and positive effects of combined K and Ct application were related to improved physiological and metabolic processes to improve yield and quality of sunflower under drought stress.


Asunto(s)
Antioxidantes/metabolismo , Quitosano/farmacología , Sequías , Helianthus/efectos de los fármacos , Potasio/farmacología , Estrés Fisiológico/efectos de los fármacos , Biomasa , Clorofila/metabolismo , Cambio Climático , Productos Agrícolas/efectos de los fármacos , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Helianthus/crecimiento & desarrollo , Helianthus/metabolismo , Agua/metabolismo
18.
Waste Manag Res ; 38(11): 1284-1294, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32347191

RESUMEN

Biomass is considered as the largest renewable energy source in the world. However, some of its inherent properties such as hygroscopicity, lower energy content, low mass density and bio-degradation on storage hinder its extensive application in energy generation processes. Torrefaction, a thermochemical process carried out at 200-300°C in a non-oxidative environment, can address these inherent problems of the biomass. In this work, torrefaction of bagasse was performed in a bench-scale tubular reactor at 250°C and 275°C with residence times of 30, 60 and 90 mins. The effects of torrefaction conditions on the elemental composition, mass yield, energy yield, oxygen/carbon (O/C) and hydrogen/carbon (H/C) ratios, higher heating values and structural composition were investigated and compared with the commercially available 'Thar 6' and 'Tunnel C' coal. Based on the targeted mass and energy yields of 80% and 90% respectively, the optimal process conditions turned out to be 250°C and 30 mins. Torrefaction of the bagasse conducted at 275°C and 90 min raised the carbon content in bagasse to 58.14% and resulted in a high heating value of 23.84 MJ/kg. The structural and thermal analysis of the torrefied bagasse indicates that the moisture, non-structural carbohydrates and hemicellulose were reduced, which induced the hydrophobicity in the bagasse and enhanced its energy value. These findings showed that torrefaction can be a sustainable pre-treatment process to improve the fuel and structural properties of biomass as a feedstock for energy generation processes.


Asunto(s)
Carbono , Celulosa , Biomasa , Hidrógeno , Temperatura
19.
Pak J Pharm Sci ; 33(1(Supplementary)): 317-323, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32122864

RESUMEN

Since ancient times humans have relied on traditional medicine and herbal formulation for the cure of various diseases and disorders. Globally, interest in use of herbal medicine has increased; as drawbacks of modern medicine and have started getting more prominent. Most of the traditional system of medicine; all in their formulations depends on plants. Traditional herbal cough products have considered to be mild, nontoxic, non-sedative and even harmless. As Syrup is commonly taken for the relief of cough; we aimed to formulate a cough syrup (Graphirine) from some common indigenous herbs; Adhatoda vasica, Piper longum and Rosa Damasena and evaluate its physicochemical parameters along with the changes in accelerated stability testing. Preformulation studies, i.e. moisture content, ash, water and ethanol extractive values of all three herbs were defined. Physicochemical factors, quantitative spectral measurement, FTIR spectrum for identification of compounds; along with accelerated stability and possible microbial fungal growth; were also checked for the formulated syrup. Each and every parameter complied with the specifications.


Asunto(s)
Antitusígenos/síntesis química , Género Justicia , Piper , Extractos Vegetales/síntesis química , Rosa , Antitusígenos/aislamiento & purificación , Composición de Medicamentos , Evaluación de Medicamentos/métodos , Humanos , Pakistán , Fitoterapia/métodos , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales
20.
Ann Hum Genet ; 83(6): 426-433, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31069794

RESUMEN

Tuberculosis (TB) is a global issue as one-third of the population worldwide is considered to be infected. TB has become a critical public health problem as a result of increasing drug resistance, which poses a challenge to current control strategies. Similar to environmental factors, genetic makeup of the host equally contributes to disease onset. We performed genotypic analysis to examine the relationship between IFNG and TB onset and drug resistance in a Pakistani population comprising 689 subjects. Notable differences were observed in the IFNG polymorphism (+874T/A) between the case and control groups. The frequency of the wild-type genotype (TT) in the controls (43.2%) was significantly higher than in the cases (25.3%) (odds ratio [OR] = 0.77, p < 0.0001), while the mutant genotype frequency (AA) (38.57%) in the cases was significantly higher than in the controls (22.6%) (OR = 1.46, p < 0.0001). The heterozygous genotype frequency (TA) did not significantly differ between the control and case groups. Compared with the controls, the variant allele (A) was approximately twice as frequent in the cases. Females and older people have a higher chance of disease development. Finally, the IFNG (+874T/A) polymorphism was not associated with drug sensitivity or resistance. However, a genotypic polymorphism of IFNG (+874T/A) was significantly associated with susceptibility to TB, and the T allele conferred protection against TB. Additional studies involving larger cohorts are needed to further explore this relationship between genetics and disease vulnerability.


Asunto(s)
Predisposición Genética a la Enfermedad , Interferón gamma/genética , Polimorfismo de Nucleótido Simple , Tuberculosis/epidemiología , Tuberculosis/genética , Adolescente , Adulto , Anciano , Niño , Farmacorresistencia Bacteriana , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pakistán/epidemiología , Fenotipo , Vigilancia de la Población , Tuberculosis/diagnóstico , Adulto Joven
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