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1.
PLoS Genet ; 18(6): e1009806, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35666722

RESUMEN

Mutation rates are of key importance for understanding evolutionary processes and predicting their outcomes. Empirical mutation rate estimates are available for a number of RNA viruses, but few are available for DNA viruses, which tend to have larger genomes. Whilst some viruses have very high mutation rates, lower mutation rates are expected for viruses with large genomes to ensure genome integrity. Alphabaculoviruses are insect viruses with large genomes and often have high levels of polymorphism, suggesting high mutation rates despite evidence of proofreading activity by the replication machinery. Here, we report an empirical estimate of the mutation rate per base per strand copying (s/n/r) of Autographa californica multiple nucleopolyhedrovirus (AcMNPV). To avoid biases due to selection, we analyzed mutations that occurred in a stable, non-functional genomic insert after five serial passages in Spodoptera exigua larvae. Our results highlight that viral demography and the stringency of mutation calling affect mutation rate estimates, and that using a population genetic simulation model to make inferences can mitigate the impact of these processes on estimates of mutation rate. We estimated a mutation rate of µ = 1×10-7 s/n/r when applying the most stringent criteria for mutation calling, and estimates of up to µ = 5×10-7 s/n/r when relaxing these criteria. The rates at which different classes of mutations accumulate provide good evidence for neutrality of mutations occurring within the inserted region. We therefore present a robust approach for mutation rate estimation for viruses with stable genomes, and strong evidence of a much lower alphabaculovirus mutation rate than supposed based on the high levels of polymorphism observed.


Asunto(s)
Nucleopoliedrovirus , Animales , Mutación , Tasa de Mutación , Nucleopoliedrovirus/genética , Spodoptera
2.
Biol Proced Online ; 26(1): 22, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969986

RESUMEN

Peste des petits ruminants (PPRV), a highly contagious viral disease, causes significant economic losses concerning sheep and goats. Recently, PPR viruses (PPRVs), have adopted new hosts and lineage IV of PPRVs represents genetic diversity within the same lineage. 350 samples, including blood, swabs, and tissues from sheep/goats, were collected during the 2020-2021 disease outbreaks in Pakistan. These samples were analysed through RT-PCR and three isolates of PPRV with accession numbers, MW600920, MW600921, and MW600922, were submitted to GenBank, based on the partial N-gene sequencing. This analysis provides a better understanding of genetic characterizations and a targeted RT-PCR approach for rapid PPRV diagnosis. An IELISA test was developed using the semi-purified antigen MW600922 isolate grown in Vero cells. The PPRV isolates currently present high divergence with the Turkish strain; conversely, similarities equivalent to 99.73% were observed for isolates collected from Pakistan. The developed indirect ELISA (IELISA) test demonstrated antibody detection rates at dilutions of 1:200 for antibodies (serum) and 1:32 for antigens. In comparison to cELISA, high specificity (85.23%) and sensitivity (90.60%) rates were observed. In contrast to the virus neutralization test (VNT), IELISA was observed to be 100% specific and 82.14% sensitive in its results. Based on these results, serological surveys conducted for PPR antibodies using IELISA can be a more effective strategy on a larger scale. Furthermore, our results demonstrate a significant breakthrough in the research in terms of cost-effectiveness and storage efficiency, and the developed IELISA test is highly recommended for use in developing countries.


Peste des petits ruminants (PPRV) is a transboundary, highly contagious, and economically significant viral disease affecting small ruminants and wildlife. PPRV, a disease that only targets animals, is the focus of the Global Eradication Programme (PPRV GEP), which aims to eradicate the disease by 2030. Following the completion of the first phase of the GEP (2017­2021), Pakistan has initiated the second phase: PPRV presence and the implementation of a control strategy. Rapid and accurate laboratory diagnosis is vital to the disease's effective control and eradication. In the present study, we have improved diagnosis by reverse transcriptase polymerase chain reaction (RT-PCR), which not only can detect low viral concentrations but also contributes to the genetic analysis of lineage-IV viruses. However, the development of cost-effective indirect ELISA (iELISA) may allow for the analysis of serum samples obtained from larger populations of small ruminants.

3.
Angew Chem Int Ed Engl ; 63(12): e202320060, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38285010

RESUMEN

Room-temperature sodium-sulfur (RT Na-S) batteries are promising for low-cost and large-scale energy storage applications. However, these batteries are plagued by safety concerns due to the highly flammable nature of conventional electrolytes. Although non-flammable electrolytes eliminate the risk of fire, they often result in compromised battery performance due to poor compatibility with sodium metal anode and sulfur cathode. Herein, we develop an additive of tin trifluoromethanesulfonate (Sn(OTf)2 ) in non-flammable phosphate electrolytes to improve the cycling stability of RT Na-S batteries via modulating the Na+ solvation environment and interface chemistry. The additive reduces the Na+ desolvation energy and enhances the electrolyte stability. Moreover, it facilitates the construction of Na-Sn alloy-based anode solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI). These interphases help to suppress the growth of Na dendrites and the dissolution/shuttling of sodium polysulfides (NaPSs), resulting in improved reversible capacity. Specifically, the Na-S battery with the designed electrolyte boosts the capacity from 322 to 906 mAh g-1 at 0.5 A g-1 . This study provides valuable insights for the development of safe and high-performance electrolytes in RT Na-S batteries.

4.
Funct Integr Genomics ; 23(1): 66, 2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36840774

RESUMEN

Mutations in Photoperiod-1 (Ppd-1) gene are known to modify flowering time and yield in wheat. We cloned TaPpd-1 from wheat and found high similarity among the three homoeologs of TaPpd-1. To clarify the characteristics of TaPpd-1 homoeologs in different photoperiod conditions for inflorescence architecture and yield, we used CRISPR/Cas9 system to generate Tappd-1 mutant plants by simultaneous modification of the three homoeologs of wheat Ppd-1. Tappd-1 mutant plants showed no off-target mutations. Four T0-edited lines under short-day length and three lines under long-day length conditions with the mutation frequency of 25% and 21%, respectively. These putative transgenic plants of all the lines were self-fertilized and generated T1 and T2 progenies and were evaluated by phenotypic and expression analysis. Results demonstrated that simultaneously edited TaPpd-1- A1, B1, and D1 homoeologs gene copies in T2_SDL-8-4, T2_SDL-4-5, T2_SDL-3-9, and T2_LDL-10-9 showed similar spike inflorescence, flowering time, and significantly increase in 1000-grain weight, grain area, grain width, grain length, plant height, and spikelets per spike due to mutation in both alleles of Ppd-B1 and Ppd-D1 homoeologs but only spike length was decreased in T2_SDL-8-4, T2_SDL-4-5, and T2_LDL-13-3 mutant lines due to mutation in both alleles of Ppd-A1 homoeolog under both conditions. Our results indicate that all TaPpd1 gene homoeologs influence wheat spike development by affecting both late flowering and earlier flowering but single mutant TaPpd-A1 homoeolog affect lowest as compared to the combination with double mutants of TaPpd-B1 and TaPpd-D1, TaPpd-A1 and TaPpd-B1, and TaPpd-A1 and TaPpd-D1 homoeologs for yield enhancement. Our findings further raised the idea that the relative expression of the various genomic copies of TaPpd-1 homoeologs may have an impact on the spike inflorescence architecture and grain morphometric features in wheat cultivars.


Asunto(s)
Fotoperiodo , Triticum , Triticum/genética , Sistemas CRISPR-Cas , Fenotipo , Grano Comestible/genética
5.
Mol Biol Rep ; 50(7): 5931-5940, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37253917

RESUMEN

BACKGROUND: Soil salinity has been affecting wheat production worldwide over past few decades. Evaluation of wheat genotypes for salinity tolerance at germination and vegetative growth level is crucial. Marker assisted selection is a technique used extensively for choosing salt-tolerant genotypes from breeding populations to introduce novel genes. METHODS AND MATERIALS: The current study's main goal was to discover salt-stress resistant genes; genetic divergence and genome-wide connection by using recently designed candidate gene-based simple-sequence-repeat markers (cg-SSRs). The phenotypic connection of morphological features during the germination growth stage i.e., germination period, root length/weight and shoot length/weight, and vegetative growth stages i.e., root length/weight and shoot length/weight were tested in a group of 50 wheat genotypes. Significant difference was observed in germination rate, root length and weight among control and saline treatments. CONCLUSION: Total 30 SSR markers were utilized to test salinity resistance genes in wheat genotypes. Three (10%) of which were monomorphic, one (3.34%) showed no result, and the other 26 (86%) were polymorphic. Using 30 polymorphic markers discovered total 37 alleles. The polymorphic information content (PIC), quantifies each SSR locus capacity to discriminate between wheat, varied from 0.00 to 0.38 with an average of 0.19. Association analysis revealed that 26 primers were associated with morphological features, 03 with root length and the remaining 23 with germination. Utilizing morphological data, stress tolerance index (STI) was designed concluding that Auqab-2000, Margala-99 and Ufaq showed better resistance against salinity among other wheat genotypes. Cluster analysis demonstrated that wheat genotypes have vast genetic variability.


Asunto(s)
Fitomejoramiento , Triticum , Triticum/genética , Pakistán , Genotipo , Tolerancia a la Sal/genética
6.
Mol Biol Rep ; 50(10): 7967-7979, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37535247

RESUMEN

BACKGROUND: Millions of people around the globe are affected by Alzheimer's disease (AD). This crippling condition has no treatment despite intensive studies. Some phytocompounds have been shown to protect against Alzheimer's in recent studies. METHODS: Thus, this work aimed to examine Bacopa monnieri phytocompounds' synergistic effects on neurodegeneration, antioxidant activity, and cognition in the scopolamine-induced AD mice model. The toxicity study of two phytocompounds: quercetin and bacopaside X revealed an LD50 of more than 2000 mg/kg since no deaths occurred. RESULTS: The neuroprotection experiment consists of 6 groups i.e., control (saline), scopolamine (1 mg/kg), donepezil (5 mg/kg), Q (25 mg/kg), BX (20 mg/kg), and Q + BX (25 mg/kg + 20 mg/kg). Visual behavioral assessment using the Morris water maze showed that animals in the diseased model group (scopolamine) moved more slowly toward the platform and exhibited greater thigmotaxis behavior than the treatment and control groups. Likewise, the concentration of biochemical NO, GSH, and MDA improved in treatment groups concerning the diseased group. mRNA levels of different marker genes including ChAT, IL-1α, IL-1 ß, TNF α, tau, and ß secretase (BACE1) improved in treatment groups with respect to the disease group. CONCLUSION: Both bacopaside X and quercetin synergistically have shown promising results in neuroprotection. Therefore, it is suggested that Q and BX may work synergistically due to their antioxidant and neuroprotective property.


Asunto(s)
Enfermedad de Alzheimer , Bacopa , Fármacos Neuroprotectores , Humanos , Ratones , Animales , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/tratamiento farmacológico , Escopolamina/farmacología , Escopolamina/uso terapéutico , Bacopa/química , Secretasas de la Proteína Precursora del Amiloide , Quercetina/farmacología , Quercetina/uso terapéutico , Neuroprotección , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Ácido Aspártico Endopeptidasas , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Aprendizaje por Laberinto
7.
Mol Biol Rep ; 51(1): 22, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110786

RESUMEN

BACKGROUND: Salinity is one of the main abiotic factors that restrict plant growth, physiology, and crop productivity is salt stress. About 33% of the total irrigated land suffers from severe salinity because of intensive underground water extraction and irrigation with brackish water. Thus, it is important to understand the genetic mechanism and identify the novel genes involved in salt tolerance for the development of climate-resilient rice cultivars. METHODS AND RESULTS: In this study, two rice genotypes with varying tolerance to salt stress were used to investigate the differential expressed genes and molecular pathways to adapt under saline soil by comparative RNA sequencing at 42 days of the seedling stage. Salt-susceptible (S3) and -tolerant (S13) genotypes revealed 3982 and 3463 differentially expressed genes in S3 and S13 genotypes. The up-regulated genes in both genotypes were substantially enriched in different metabolic processes and binding activities. Biosynthesis of secondary metabolites, phenylpropanoid biosynthesis, and plant signal transduction mechanisms were highly enriched. Salt-susceptible and -tolerant genotypes shared the same salt adaptability mechanism with no significant quantitative differences at the transcriptome level. Moreover, bHLH, ERF, NAC, WRKY, and MYB transcription factors were substantially up-regulated under salt stress. 391 out of 1806 identified novel genes involved in signal transduction mechanisms. Expression profiling of six novel genes further validated the findings from RNA-seq data. CONCLUSION: These findings suggest that the differentially expressed genes and molecular mechanisms involved in salt stress adaptation are conserved in both salt-susceptible and salt-tolerant rice genotypes. Further molecular characterization of novel genes will help to understand the genetic mechanism underlying salt tolerance in rice.


Asunto(s)
Oryza , Transcriptoma , Transcriptoma/genética , Oryza/metabolismo , Perfilación de la Expresión Génica , Estrés Salino , Genotipo , Regulación de la Expresión Génica de las Plantas/genética , Estrés Fisiológico/genética
8.
Skin Res Technol ; 29(11): e13519, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38009027

RESUMEN

Automatic classification of Lyme disease rashes on the skin helps clinicians and dermatologists' probe and investigate Lyme skin rashes effectively. This paper proposes a new in-depth features fusion system to classify Lyme disease rashes. The proposed method consists of two main steps. First, three different deep learning models, Densenet201, InceptionV3, and Exception, were trained independently to extract the deep features from the erythema migrans (EM) images. Second, a deep feature fusion mechanism (meta classifier) is developed to integrate the deep features before the final classification output layer. The meta classifier is a basic deep convolutional neural network trained on original images and features extracted from base level three deep learning models. In the feature fusion mechanism, the last three layers of base models are dropped out and connected to the meta classifier. The proposed deep feature fusion method significantly improved the classification process, where the classification accuracy was 98.97%, which is particularly impressive than the other state-of-the-art models.


Asunto(s)
Enfermedad de Lyme , Redes Neurales de la Computación , Humanos , Piel , Enfermedad de Lyme/diagnóstico
9.
Phys Chem Chem Phys ; 25(1): 428-438, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36477765

RESUMEN

Here, we introduce the synthesis and deposition of organic/inorganic composite ink on cellulose paper using a rapid ultrasonic spray deposition approach that can be incorporated as a counter electrode (CE) in flexible dye-sensitized solar cells (FDSSCs). The composite ink comprised a copper indium sulfide (CuInS2) nanostructure ink and dispersion of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) in water. Fabricated counter electrodes are biodegradable, environment-friendly, flexible, and economical and meet the requirements for sustainable green energy. To evaluate the catalytic activities and power conversion efficiencies of DSSCs, the produced CuInS2/PEDOT:PSS composite ink-based CEs were compared with PEDOT:PSS counter electrodes. Cyclic voltammetry studies found that CuInS2/PEDOT:PSS had a greater cathodic charge transfer current density (Jc) (-1.23 mA cm-2). Moreover, it was found that the potential separation values are small, which indicate a stronger catalytic activity than PEDOT:PSS counter electrodes. The observed exchange current density (J0) was 3.98 mA cm-2, while the limiting current density (Jlim) increased to 45.7 mA cm-2, indicating a fast redox diffusion rate of the CuInS2/PEDOT:PSS CE. The photovoltaic performances of CuInS2/PEDOT:PSS and PEDOT: PSS-based DSSC's were measured and determined to be 5.66% and 4.41%, respectively, while the performance of CuInS2/PEDOT:PSS FDSSC composed of cellulose paper was 1.06%.

10.
Sensors (Basel) ; 22(14)2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35890947

RESUMEN

High end-to-end delay is a significant challenge in the data collection process in the underwater environment. Autonomous Underwater Vehicles (AUVs) are a considerably reliable source of data collection if they have significant trajectory movement. Therefore, in this paper, a new routing algorithm known as Elliptical Shaped Efficient Data Gathering (ESEDG) is introduced for the AUV movement. ESEDG is divided into two phases: first, an elliptical trajectory has been designed for the horizontal movement of the AUV. In the second phase, the AUV gathers data from Gateway Nodes (GNs) which are associated with Member Nodes (MNs). For their association, an end-to-end delay model is also presented in ESEDG. The hierarchy of data collection is as follows: MNs send data to GNs, the AUV receives data from GNs, and forwards it to the sink node. Furthermore, the ESEDG was evaluated on the network simulator NS-3 version 3.35, and the results were compared to existing data collection routing protocols DSG-DGA, AEEDCO, AEEDCO-A, ALP, SEDG, and AEDG. In terms of network throughput, end-to-end delay, lifetime, path loss, and energy consumption, the results showed that ESEDG outperformed the baseline routing protocols.

11.
Molecules ; 27(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36234756

RESUMEN

Background: Type 2 diabetes mellitus (DM2) is a chronic and sometimes fatal condition which affects people all over the world. Nanotherapeutics have shown tremendous potential to combat chronic diseases­including DM2­as they enhance the overall impact of drugs on biological systems. Greenly synthesized silver nanoparticles (AgNPs) from Catharanthus roseus methanolic extract (C. AgNPs) were examined primarily for their cytotoxic and antidiabetic effects. Methods: Characterization of C. AgNPs was performed by UV−vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and atomic force microscopy (AFM). The C. AgNPs were trialed on Vero cell line and afterwards on an animal model (rats). Results: The C. AgNPs showed standard structural and functional characterization as revealed by FTIR and XRD analyses. The zetapotential analysis indicated stability while EDX analysis confirmed the formation of composite capping with Ag metal. The cytotoxic effect (IC50) of C. AgNPs on Vero cell lines was found to be 568 g/mL. The animal model analyses further revealed a significant difference in water intake, food intake, body weight, urine volume, and urine sugar of tested rats after treatment with aqueous extract of C. AgNPs. Moreover, five groups of rats including control and diabetic groups (NC1, PC2, DG1, DG2, and DG3) were investigated for their blood glucose and glycemic control analysis. Conclusions: The C. AgNPs exhibited positive potential on the Vero cell line as well as on experimental rats. The lipid profile in all the diabetic groups (DG1-3) were significantly increased compared with both of the control groups (p < 0.05). The present study revealed the significance of C. AgNPs in nanotherapeutics.


Asunto(s)
Catharanthus , Diabetes Mellitus Tipo 2 , Nanopartículas del Metal , Animales , Antibacterianos/farmacología , Glucemia , Catharanthus/química , Línea Celular , Hipoglucemiantes/farmacología , Lípidos , Nanopartículas del Metal/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Agua , Difracción de Rayos X
12.
Pak J Pharm Sci ; 35(3): 731-739, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35791470

RESUMEN

Melanoma is one of the most common skin infections, has triggered significant morbidity and mortality across the globe. Previous studies have reported that mutations in CDKN2A signalling network is associated with cutaneous malignant melanoma. In the present study, initially, the BioGrid database was utilized, and then hierarchical clustering was performed to identify the CDKN2A signature pathways. In addition, a GO Enrichment analysis was investigated using DAVID (n=187 genes) toolkit. Subsequently, the cBioPortal cancer genomic platform was exploited using alteration ranked frequency to determine the role of the CDKN2A signaling network in 363 samples of cutaneous malignant melanoma patients and we find that CDKN2A and its close interactors PTEN and HUWE1 show highest mutations. Further, we systematically employed molecular docking approach via MOE to target PTEN, CDKN2A and HUWE1 with chloroquine which is naturally occurring in medicinal plant Nigella sativa (NS) and observed virtuous interactions between all receptors and ligand molecules with a binding energy of -11.379, -10.324 and -9.06 Kcal/mol, respectively. The outcomes obtained stipulate a vigorous research resource for using chloroquine as a multitargeted anticancer drug. This novel evidence should help the development of effective therapeutic compounds for the treatment of cancer. Our results reveal that chloroquine is a relevant and novel potential therapeutic drug for the treatment of melanoma.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Cloroquina , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Simulación del Acoplamiento Molecular , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Melanoma Cutáneo Maligno
13.
Mol Biol Rep ; 48(3): 2411-2427, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33782785

RESUMEN

Pseudo-response regulator (PRR) gene family members play a significant role in plant circadian clocks, flowering time inflorescence architecture development during transition from vegetative growth phase to reproductive phase. In current study, we analyzed the expression profiling, phylogenetic relationship, and molecular characterization of PRR gene family members of common wheat by using IWGSC Ref seq v1.1 wheat genome database with a coverage rate of 90%. By using bioinformatic approach total 20 candidate gene sequences were identified and divided into six groups and four clades. It was found that mostly genes have same number of exons and introns showed similar features because they originated through duplication events during evolution processes. Although all the proteins have conserved PRR domains, but some are distinct in their sequences suggesting functional divergence. By comparative synteny analysis it was revealed that Group 1, 2, 3 and 11-D of group 4 have duplication events while group 5 and TaPRR9-B,10-D showed conservation with previously identified PRR members from rice. While expression variation of six groups from each analysis matches with each other. Five groups highly expressed in leaf, spike, and roots in pattern like leaf > spike > root at all three stages booting, heading and anthesis of spike development. This suggests that TaPRR genes play important roles in different photoperiod signaling pathways in different organs at different stages of spike development and flowering via unknown pathway. These findings will also provide comprehensive knowledge about future investigations on wheat PRR family members involved in complex network of circadian system for plant development.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genes Reguladores , Genoma de Planta , Familia de Multigenes , Triticum/genética , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Emparejamiento Base/genética , Cromosomas de las Plantas/genética , Secuencia Conservada , Exones/genética , Genes de Plantas , Intrones/genética , Especificidad de Órganos/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sintenía/genética
14.
Waste Manag Res ; 38(11): 1269-1277, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32077381

RESUMEN

The present work is focused on pyrolysis of polystyrene waste for production of combustible hydrocarbons. The experiments were performed in an indigenously made furnace in the presence of a laboratory synthesised copper oxide. The pyrolysis products were collected and characterised. The Fourier transform infrared spectra showed that the liquid fraction contains C-H, C-O, C-C, C=C and O-H bonds, which correspond to various aliphatic and aromatic compounds. Gas chromatography-mass spectrometry traced compounds ranging from C1 to C4 in the gaseous fraction, whereas in the liquid fraction 15 components ranging from C3 to C24 were detected. From the results it has been concluded that CuO as a catalyst not only increased the liquid yield but also reduced the degradation temperature to great extent. Fuel properties of the pyrolysis oil were determined and compared with standard values of commercial fuel oil. The comparison suggested potential application of pyrolysis oil for domestic and commercial use.


Asunto(s)
Poliestirenos , Pirólisis , Catálisis , Cobre , Calor , Hidrocarburos , Óxidos
15.
Waste Manag Res ; 38(2): 202-212, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31405341

RESUMEN

Due to a huge increase in polymer production, a tremendous increase in municipal solid waste is observed. Every year the existing landfills for disposal of waste polymers decrease and the effective recycling techniques for waste polymers are getting more and more important. In this work pyrolysis of waste polystyrene was performed in the presence of a laboratory synthesized copper oxide. The samples were pyrolyzed at different heating rates that is, 5°Cmin-1, 10°Cmin-1, 15°Cmin-1 and 20°Cmin-1 in a thermogravimetric analyzer in inert atmosphere using nitrogen. Thermogravimetric data were interpreted using various model fitting (Coats-Redfern) and model free methods (Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman). Thermodynamic parameters for the reaction were also determined. The activation energy calculated applying Coats-Redfern, Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman models were found in the ranges 105-148.48 kJmol-1, 99.41-140.52 kJmol-1, 103.67-149.15 kJmol-1 and 99.93-141.25 kJmol-1, respectively. The lowest activation energy for polystyrene degradation in the presence of copper oxide indicates the suitability of catalyst for the decomposition reaction to take place at lower temperature. Moreover, the obtained kinetics and thermodynamic parameters would be very helpful in determining the reaction mechanism of the solid waste in a real system.


Asunto(s)
Poliestirenos , Residuos Sólidos , Calefacción , Cinética , Termogravimetría
16.
J Invertebr Pathol ; 153: 20-29, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29425966

RESUMEN

The cotton leafworm Spodoptera litura is a polyphagous insect. It has recently made a comeback as a primary insect pest of cotton in Pakistan due to reductions in pesticide use on the advent of genetically modified cotton, resistant to Helicoverpa armigera. Spodoptera litura nucleopolyhedrovirus (SpltNPV) infects S. litura and is recognized as a potential candidate to control this insect. Twenty-two NPV isolates were collected from S. litura from different agro-ecological zones (with collection sites up to 600 km apart) and cropping systems in Pakistan to see whether there is spatial dispersal and adaptation of the virus and/or adaptation to crops. Therefore, the genetic make-up and biological activity of these isolates was measured. Among the SpltNPV isolates tested for speed of kill in 3rd instar larvae of S. litura, TAX1, SFD1, SFD2 and GRW1 were significantly faster killing isolates than other Pakistani isolates. Restriction fragment length analysis of the DNA showed that the Pakistan SpltNPV isolates are all variants of a single SpltNPV biotype. The isolates could be grouped into three genogroups (A-C). The speed of kill of genogroup A viruses was higher than in group C according to a Cox' proportional hazards analysis. Sequence analysis showed that the Pakistan SpltNPV isolates are more closely related to each other than to the SpltNPV type species G2 (Pang et al., 2001). This suggests a single introduction of SpltNPV into Pakistan. The SpltNPV-PAK isolates are distinct from Spodoptera littoralis nucleopolyhedrovirus. There was a strong correlation between geographic spread and the genetic variation of SpltNPV, and a marginally significant correlation between the latter and the cropping system. The faster killing isolates may be good candidates for biological control of S. litura in Pakistan.


Asunto(s)
Nucleopoliedrovirus/genética , Spodoptera/virología , Adaptación Fisiológica , Animales , Genes Virales , Genotipo , Control Biológico de Vectores/métodos
17.
Biotechnol Lett ; 39(10): 1441-1451, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28726080

RESUMEN

Seeds play essential roles in plant life cycle and germination is a complex process which is associated with different phases of water imbibition. Upon imbibition, seeds begin utilization of storage substances coupled with metabolic activity and biosynthesis of new proteins. Regeneration of organelles and emergence of radicals lead to the establishment of seedlings. All these activities are regulated in coordinated manners. Translation is the requirement of germination of seeds via involvements of several proteins like beta-amylase, starch phosphorylase. Some important proteins involved in seed germination are discussed in this review. In the past decade, several proteomic studies regarding seed germination of various species such as rice, Arabidopsis have been conducted. We face A paucity of proteomic data with respect to woody plants e.g. Fagus, Pheonix etc. With particular reference to Cyclobalnopsis gilva, a woody plant having low seed germination rate, no proteomic studies have been conducted. The review aims to reveal the complex seed germination mechanisms from woody and herbaceous plants that will help in understanding different seed germination phases and the involved proteins in C. gilva.


Asunto(s)
Proteínas de Plantas/metabolismo , Proteómica/métodos , Quercus/fisiología , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Germinación , Quercus/metabolismo
18.
Planta ; 241(5): 1173-87, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25630441

RESUMEN

MAIN CONCLUSION: WsMAGO2 a duplicated protein in Withania through interactions with MPF2-like proteins affects male fertility by producing fewer flowers and aborted non-viable pollens/seeds regulated by anther-specific GAATTTGTGA motif. The MAGO NASHIs are highly conserved genes that encode proteins known to be involved in RNA physiology and many other developmental processes including germ cell differentiation in animals. However, their structural and functional implications in plants as fertility function proteins remained fragmented. MAGO (shorter name of MAGO NASHI) proteins form heterodimers with MPF2-like MADS-box proteins which are recruited in calyx identity and male fertility in Solanaceous plants. Four MAGO genes namely WsMAGO1 and WsMAGO2 and TaMAGO1 and TaMAGO2 were isolated from Withania somnifera and Tubocapsicum anomalum, respectively. These genes have duplicated probably due to whole genome duplication event. Dysfunction of WsMAGO2 through double-stranded RNAi in Withania revealed suppression of RNA transcripts, non-viable pollens, fewer flowers and aborted non-viable seeds in the developing berry suggesting a role of this protein in many traits particularly male fertility. WsMAGO2 flaunted stronger yeast 2-hybrid interactions with MPF2-like proteins WSA206, WSB206 and TAB201 than other MAGO counterparts. The native transcripts of WsMAGO2 culminated in stamens and seed-bearing berries though other MAGO orthologs also exhibited expression albeit at lower level. Coding sequences of the two orthologs are highly conserved, but they differ substantially in their upstream promoter regions. Remarkably, WsMAGO2 promoter is enriched with many anther-specific cis-motifs common in fertility function genes promoters. Among them, disruption of GAATTTGTGA abolished YFP/GUS gene expression in anthers alluding towards its involvement in regulating expression of MAGO in anther. Our findings support a possible recruitment of WsMAGO2 in fertility trait in Withania. These genes have practical application in hybrid production through cytoplasmic male sterility maintenance for enhancement in crops yield.


Asunto(s)
Duplicación de Gen , Proteínas de Plantas/fisiología , Withania/metabolismo , Fertilidad , Técnicas de Silenciamiento del Gen , Genes de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Withania/genética
19.
Nano Lett ; 14(2): 416-22, 2014 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-24400876

RESUMEN

For the first time, we report the electrochemical activity of anatase TiO2 nanorods in a Na cell. The anatase TiO2 nanorods were synthesized by a hydrothermal method, and their surfaces were coated by carbon to improve the electric conductivity through carbonization of pitch at 700 °C for 2 h in Ar flow. The resulting structure does not change before and after the carbon coating, as confirmed by X-ray diffraction (XRD). Transmission electron microscopic images confirm the presence of a carbon coating on the anatase TiO2 nanorods. In cell tests, anodes of bare and carbon-coated anatase TiO2 nanorods exhibit stable cycling performance and attain a capacity of about 172 and 193 mAh g(-1) on the first charge, respectively, in the voltage range of 3-0 V. With the help of the conductive carbon layers, the carbon-coated anatase TiO2 delivers more capacity at high rates, 104 mAh g(-1) at the 10 C-rate (3.3 A g(-1)), 82 mAh g(-1) at the 30 C-rate (10 A g(-1)), and 53 mAh g(-1) at the 100 C-rate (33 A g(-1)). By contrast, the anode of bare anatase TiO2 nanorods delivers only about 38 mAh g(-1) at the 10 C-rate (3.3 A g(-1)). The excellent cyclability and high-rate capability are the result of a Na(+) insertion and extraction reaction into the host structure coupled with Ti(4+/3+) redox reaction, as revealed by X-ray absorption spectroscopy.

20.
Micromachines (Basel) ; 15(2)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38399011

RESUMEN

This paper reports on noise modeling of a piezoelectric charge accelerometer with a signal conditioning circuit. The charge output is converted into voltage and amplified using a JFET operational amplifier that has high input resistance and low noise. The noise sources in the whole system include electrical and mechanical thermal noises of the accelerometer, thermal noises of resistors, and voltage and current noises of the operational amplifier. Noise gain of each source is derived from small signal circuit analysis. It is found that the feedback resistor of the operational amplifier is a major source of noise in low frequencies, whereas electrical thermal noise of the accelerometer dominates the rest of spectrum. This method can be used to pair a highly sensitive sensor with a single JFET operational amplifier instead of a multi-stage signal conditioning circuit.

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