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1.
Environ Pollut ; 338: 122689, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37804901

RESUMO

Abiogenic silicon (Si), though deemed a quasi-nutrient, remains largely inaccessible to plants due to its prevalence within mineral ores. Nevertheless, the influence of Si extends across a spectrum of pivotal plant processes. Si emerges as a versatile boon for plants, conferring a plethora of advantages. Notably, it engenders substantial enhancements in biomass, yield, and overall plant developmental attributes. Beyond these effects, Si augments the activities of vital antioxidant enzymes, encompassing glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), among others. It achieves through the augmentation of reactive oxygen species (ROS) scavenging gene expression, thus curbing the injurious impact of free radicals. In addition to its effects on plants, Si profoundly ameliorates soil health indicators. Si tangibly enhances soil vitality by elevating soil pH and fostering microbial community proliferation. Furthermore, it exerts inhibitory control over ions that could inflict harm upon delicate plant cells. During interactions within the soil matrix, Si readily forms complexes with potentially toxic metals (PTEs), encapsulating them through Si-PTEs interactions, precipitative mechanisms, and integration within colloidal Si and mineral strata. The amalgamation of Si with other soil amendments, such as biochar, nanoparticles, zeolites, and composts, extends its capacity to thwart PTEs. This synergistic approach enhances soil organic matter content and bolsters overall soil quality parameters. The utilization of Si-based fertilizers and nanomaterials holds promise for further increasing food production and fortifying global food security. Besides, gaps in our scientific discourse persist concerning Si speciation and fractionation within soils, as well as its intricate interplay with PTEs. Nonetheless, future investigations must delve into the precise functions of abiogenic Si within the physiological and biochemical realms of both soil and plants, especially at the critical juncture of the soil-plant interface. This review seeks to comprehensively address the multifaceted roles of Si in plant and soil systems during interactions with PTEs.


Assuntos
Silício , Poluentes do Solo , Silício/metabolismo , Solo/química , Antioxidantes/metabolismo , Plantas/metabolismo , Glutationa/metabolismo , Minerais/metabolismo , Poluentes do Solo/análise
2.
Environ Monit Assess ; 195(10): 1207, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37707632

RESUMO

There is a growing concern about inappropriate waste disposal and its negative impact on human health and the environment. The objective of this study is to understand household waste segregation intention considering psychological, institutional, and situational factors simultaneously. Insights into the motivations of household waste segregation drivers may assist in a better knowledge of how to pursue the most efficient and effective initiatives. For this purpose, data from a representative sample comprising 849 households is obtained from the twin cities of Islamabad and Rawalpindi (Pakistan). The empirical analysis employs a Structural Equation Modeling (SEM) approach, showing that policy instruments have significant direct and indirect impacts on households' segregation intentions. The results highlight that government policy instruments strengthen personal and perceived norms for waste segregation intentions, resulting in an external intervention that would encourage intrinsic motivation. Therefore, policy actions become the main entry point for initiating waste segregation behavior. Public policy must continue to emphasize waste segregation since it may help resource recovery. This is imperative because the environment is a shared resource, and its conservation increases social welfare.


Assuntos
Monitoramento Ambiental , Intenção , Humanos , Paquistão , Cidades , Análise de Classes Latentes , Política Pública
3.
Sensors (Basel) ; 22(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36365879

RESUMO

Smart home systems (SHSs) are a modern lifestyle trend, changing daily lives in the most intuitive way. To connect and operate various smart devices under one system, an accurate, convenient, and secure control method is of utmost significance. Nowadays, most smart home control systems are based on radio-frequency (RF) technologies such as Bluetooth, Wi-Fi, and Zigbee. They tend to suffer from poor location accuracy in high-density environments due to the interference and noise in RF signals as well as their penetration through walls, leading to security vulnerabilities and low-precision control. To address these issues, this paper presents a smart home control system based on visible light communication (VLC), with enhanced security and accurate localization for precise and convenient control. The system includes an AC lightbulb, a smartphone running the position and control applications, and a cloud server with location-based access and a database of smart home devices. The design of the AC lightbulb integrates VLC and Bluetooth connectivity in a standard form factor for easy installation and plug-n-play capability. A smartphone camera-based 3D indoor positioning and orientation algorithm that allows precise control by pointing the smartphone the device is also presented. We demonstrate the feasibility of this system through prototype implementation and experimental verification.

4.
Front Microbiol ; 13: 961794, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033855

RESUMO

Alfalfa plays a significant role in the pasture ecosystems of China's north, northeast, and northwest regions. It is an excellent forage for livestock, improves soil structure, prevents soil erosion, and has ecological benefits. Presently root rot is a significant threat to the alfalfa productivity because of the survival of the pathogens as soil-borne and because of lack of microbial competition in the impoverished nutrient-deficient soils and resistant cultivars. Furthermore, these regions' extreme ecological and environmental conditions predispose alfalfa to root rot. Moisture and temperature, in particular, have a considerable impact on the severity of root rot. Pathogens such as Fusarium spp. and Rhizoctonia solani are predominant, frequently isolated, and of major concern. These pathogens work together as disease complexes, so finding a host genotype resistant to disease complexes is challenging. Approaches to root rot control in these regions include mostly fungicides treatments and cultural practices and very few reports on the usage of biological control agents. As seed treatment, fungicides such as carbendazim are frequently used to combat root rot; however, resistance to fungicides has arisen. However, breeding and transgenic approaches could be more efficient and sustainable long-term control strategies, especially if resistance to disease complexes may be identified. Yet, research in China is mainly limited to field investigation of root rot and disease resistance evaluation. In this review, we describe climatic conditions of pastoral regions and the role of alfalfa therein and challenges of root rot, the distribution of root rot in the world and China, and the impact of root rot pathogens on alfalfa in particular R. solani and Fusarium spp., effects of environmental factors on root rot and summarize to date disease management approach.

5.
Ecotoxicol Environ Saf ; 242: 113952, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35999767

RESUMO

Environmental pollution of heavy metals (HMs), mainly due to anthropogenic activities, has received growing attention in recent decades. HMs, especially the non-essential carcinogenic ones, including chromium (Cr), cadmium (Cd), mercury (Hg), aluminum (Al), lead (Pb), and arsenic (As), have appeared as the most significant air, water, and soil pollutants, which adversely affect the quantity, quality, and security of plant-based food all over the world. Plants exposed to HMs could experience significant decline in growth and yield. To avoid or tolerate the toxic effects of HMs, plants have developed complicated defense mechanisms, including absorption and accumulation of HMs in cell organelles, immobilization by forming complexes with organic chelates, extraction by using numerous transporters, ion channels, signalling cascades, and transcription elements, among others. OMICS strategies have developed significantly to understand the mechanisms of plant transcriptomics, genomics, proteomics, metabolomics, and ionomics to counter HM-mediated stress stimuli. These strategies have been considered to be reliable and feasible for investigating the roles of genomics (genomes), transcriptomic (coding), mRNA transcripts (non-coding), metabolomics (metabolites), and ionomics (metal ions) to enhance stress resistance or tolerance in plants. The recent developments in the mechanistic understandings of the HMs-plant interaction in terms of their absorption, translocation, and toxicity invasions at the molecular and cellular levels, as well as plants' response and adaptation strategies against these stressors, are summarized in the present review. Transcriptomics, genomics, metabolomics, proteomics, and ionomics for plants against HMs toxicities are reviewed, while challenges and future recommendations are also discussed.


Assuntos
Arsênio , Mercúrio , Metais Pesados , Poluentes do Solo , Arsênio/análise , Mercúrio/análise , Metais Pesados/análise , Plantas/genética , Solo , Poluentes do Solo/análise
6.
Front Plant Sci ; 13: 851079, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860541

RESUMO

Recent technological advances in next-generation sequencing (NGS) technologies have dramatically reduced the cost of DNA sequencing, allowing species with large and complex genomes to be sequenced. Although bread wheat (Triticum aestivum L.) is one of the world's most important food crops, efficient exploitation of molecular marker-assisted breeding approaches has lagged behind that achieved in other crop species, due to its large polyploid genome. However, an international public-private effort spanning 9 years reported over 65% draft genome of bread wheat in 2014, and finally, after more than a decade culminated in the release of a gold-standard, fully annotated reference wheat-genome assembly in 2018. Shortly thereafter, in 2020, the genome of assemblies of additional 15 global wheat accessions was released. As a result, wheat has now entered into the pan-genomic era, where basic resources can be efficiently exploited. Wheat genotyping with a few hundred markers has been replaced by genotyping arrays, capable of characterizing hundreds of wheat lines, using thousands of markers, providing fast, relatively inexpensive, and reliable data for exploitation in wheat breeding. These advances have opened up new opportunities for marker-assisted selection (MAS) and genomic selection (GS) in wheat. Herein, we review the advances and perspectives in wheat genetics and genomics, with a focus on key traits, including grain yield, yield-related traits, end-use quality, and resistance to biotic and abiotic stresses. We also focus on reported candidate genes cloned and linked to traits of interest. Furthermore, we report on the improvement in the aforementioned quantitative traits, through the use of (i) clustered regularly interspaced short-palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated gene-editing and (ii) positional cloning methods, and of genomic selection. Finally, we examine the utilization of genomics for the next-generation wheat breeding, providing a practical example of using in silico bioinformatics tools that are based on the wheat reference-genome sequence.

7.
Sci Rep ; 12(1): 2384, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149746

RESUMO

Effective and efficient use of energy is key to sustainable industrial and economic growth in modern times. Demand-side management (DSM) is a relatively new concept for ensuring efficient energy use at the consumer level. It involves the active participation of consumers in load management through different incentives. To enable the consumers for efficient energy management, it is important to provide them information about the energy consumption patterns of their appliances. Appliance load monitoring (ALM) is a feedback system used for providing feedback to customers about their power consumption of individual appliances. For accessing appliance power consumption, the determination of the operating status of various appliances through feedback systems is necessary. Two major approaches used for ALM are intrusive load monitoring (ILM) and non-intrusive load monitoring (NILM). In this paper, a hybrid adaptive-neuro fuzzy inference system (ANFIS) is used as an application for NILM. ANFIS model being sophisticated was difficult to work with, but ANFIS model helps to achieve better results than other competent approaches. An ANFIS system is developed for extracting appliance features and then a fine tree classifier is used for classifying appliances having more than 1 kW power rating based on the extracted feature. Several case studies have been performed using ANFIS on a publicly available United Kingdom Domestic Appliance Level Electricity (UK-Dale dataset). The simulation results obtained from the ANFIS for NILM are compared with relevant literature to show the performance of the proposed technique. The results prove that the novel application of ANFIS gives better performance for solving the NILM problem as compared to the other existing techniques.

8.
Sci Rep ; 11(1): 17505, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471165

RESUMO

The tremendous increase in industrial development and urbanization has become a severe threat to the Chinese climate and food security. The Agricultural Production System Simulator model was used to simulate soil nitrogen in black soil in Yangling Jilin Province for 20 years. The observed values are consistent with the simulated values. The predicted values of total soil NO3--N and NH4+-N nitrogen are 10 kg ha-1 and 5 kg ha-1 higher than the observed values. The total soil NO3--N loss has the same trend as the rainfall, and it increases with the number of rainfall days over the years. The average 20 years losses of NO3--N and NH4+-N observed were 1375.91 kg ha-1, and 9.24 kg ha-1, while in the simulation increase was 1387.01 kg ha-1 and 9.28 kg ha-1, respectively. The difference between the observed and simulated values of NO3--N and NH4+-N of mean loss was 11.15 kg ha-1 and 0.04 kg ha-1 respectively. Moreover, our findings highlight the opportunity further to improve management policies (especially for nitrogen) to maintain crop yield.

9.
Sci Rep ; 11(1): 1958, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479268

RESUMO

Silicon (Si), as a quasi-essential element, has a vital role in alleviating the damaging effects of various environmental stresses on plants. Cadmium (Cd) stress is severe abiotic stress, especially in acidic ecological conditions, and Si can demolish the toxicity induced by Cd as well as acidic pH on plants. Based on these hypotheses, we demonstrated 2-repeated experiments to unfold the effects of Si as silica gel on the root morphology and physiology of wheat seedling under Cd as well as acidic stresses. For this purpose, we used nine treatments with three levels of Si nanoparticles (0, 1, and 3 mmol L-1) derived from sodium silicate (Na2SiO3) against three concentrations of Cd (0, 50, and 200 µmol L-1) in the form of cadmium chloride (CdCl2) with three replications were arranged in a complete randomized design. The pH of the nutrient solution was adjusted at 5. The averages of three random replications showed that the mutual impacts of Si and Cd in acidic pH on wheat roots depend on the concentrations of Si and Cd. The collective or particular influence of low or high levels of Si (1 or 3 mM) and acidic pH (5) improved the development of wheat roots, and the collective influence was more significant than that of a single parallel treatment. The combined effects of low or high concentrations of Cd (50 or 200 µM) and acidic pH significantly reduced root growth and biomass while increased antioxidants, and reactive oxygen species (ROS) contents. The incorporation of Si (1 or 3 mmol L-1) in Cd-contaminated acidic nutrient solution promoted the wheat root growth, decreased ROS contents, and further increased the antioxidants in the wheat roots compared with Cd single treatments in acidic pH. The demolishing effects were better with a high level of Si (3 mM) than the low level of Si (1 Mm). In conclusion, we could suggest Si as an effective beneficial nutrient that could participate actively in several morphological and physiological activities of roots in wheat plants grown under Cd and acidic pH stresses.

10.
Front Genet ; 12: 818880, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111207

RESUMO

MADS-box gene family members play multifarious roles in regulating the growth and development of crop plants and hold enormous promise for bolstering grain yield potential under changing global environments. Bread wheat (Triticum aestivum L.) is a key stable food crop around the globe. Until now, the available information concerning MADS-box genes in the wheat genome has been insufficient. Here, a comprehensive genome-wide analysis identified 300 high confidence MADS-box genes from the publicly available reference genome of wheat. Comparative phylogenetic analyses with Arabidopsis and rice MADS-box genes classified the wheat genes into 16 distinct subfamilies. Gene duplications were mainly identified in subfamilies containing unbalanced homeologs, pointing towards a potential mechanism for gene family expansion. Moreover, a more rapid evolution was inferred for M-type genes, as compared with MIKC-type genes, indicating their significance in understanding the evolutionary history of the wheat genome. We speculate that subfamily-specific distal telomeric duplications in unbalanced homeologs facilitate the rapid adaptation of wheat to changing environments. Furthermore, our in-silico expression data strongly proposed MADS-box genes as active guardians of plants against pathogen insurgency and harsh environmental conditions. In conclusion, we provide an entire complement of MADS-box genes identified in the wheat genome that could accelerate functional genomics efforts and possibly facilitate bridging gaps between genotype-to-phenotype relationships through fine-tuning of agronomically important traits.

11.
Sci Total Environ ; 754: 142188, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254942

RESUMO

Cadmium (Cd) toxicity in paddy soil and accumulation in rice plants and grains have got global concern due to its health effects. This review highlights the effects of soil factors including soil organic matter, soil pH, redox potential, and soil microbes which influencing Cd uptake by rice plant. Therefore, a comprehensive review of innovative and environmentally friendly management practices for managing Cd stress in rice is lacking. Thus, this review discusses the effect of Cd toxicity in rice and describes management strategies to offset its effects. Moreover, future research thrusts to reduce its uptake by rice has also been highlighted. Through phytoremediation, Cd may be extracted and stabilized in the soil while through microbes Cd can be sequestrated inside the microbial bodies. Increased Cd uptake in hyperaccumulator plants to remediate and convert the toxic form of Cd into non-toxic forms. While in chemical remediation, Cd can be washed out, immobilized and stabilized in the soil through chemical amendments. The organic amendments may help through an increase in soil pH, adsorption in its functional groups, the formation of complexations, and the conversion of exchangeable to residual forms. Developing rice genotypes with restricted Cd uptake and reduced accumulation in grain through conventional and marker-assisted breeding are fundamental keys for safe rice production. In this regard, the use of molecular techniques including identification of QTLs, CRISPR/Cas9, and functional genomics may be quite helpful.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Cádmio/toxicidade , Grão Comestível/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
12.
PLoS One ; 15(12): e0243174, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33301482

RESUMO

Iron (Fe) and manganese (Mn) are nutritional components of rice, plays an important role in its physiological processes and can minimize absorption of cadmium (Cd) in rice. Fe, Mn, and Cd transporters such as CAL1, OsNRAMP5, OsNRAMP1, OsIRT1, OsHMA3, and OsNAAT1 regulate uptake of Cd in rice. However, the effect of exogenous application of Fe, and Mn on the accumulation of Cd and relative expression (RE) of these transporters in rice has not been investigated. Therefore, a hydroponic culture experiment was conducted to investigate the impact of Fe and Mn on Cd uptake and RE of these transporters in rice. The results showed that the Fe and Mn application significantly decreased Cd in the roots and shoots of rice. Whereas, Cd concentration in the rice significantly increased with increasing Cd concentration in the solution. The addition of manganese in the culture medium can reduce the cadmium content of rice roots by 11.9-82.3% and shoots by 11.6-85.0%, while the addition of iron in the culture medium can reduce the cadmium content of rice roots and shoots by 26-65% and 9-683% respectively. Meanwhile, application of sufficient doses of Fe and Cd in solution culture increased RE of CAL1, OsNRAMP5, OsNRAMP1, OsIRT1, and OsNAAT1 in roots, whereas expression level of OsHMA3 was decreased. Similarly, expression level of CAL1, OsNRAMP5, and OsNRAMP1 significantly increased in roots in high Cd and Mn deficient treatments. This may be concluded that the Cd increases expression of CAL1, OsNRAMP5, OsNRAMP1, OsIRT1, and OsNAAT1 but decreases OsHMA3 expression in rice roots, which resulted in increased Cd uptake in hydroponically grown rice.


Assuntos
Cádmio/metabolismo , Ferro/farmacologia , Manganês/farmacologia , Oryza/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hidroponia , Oryza/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Reação em Cadeia da Polimerase
13.
Sci Rep ; 10(1): 18381, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33087828

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
Pharmaceutics ; 12(7)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659966

RESUMO

Aptamers are synthetic single-stranded DNA or RNA sequences selected from combinatorial oligonucleotide libraries through the well-known in vitro selection and iteration process, SELEX. The last three decades have witnessed a sudden boom in aptamer research, owing to their unique characteristics, like high specificity and binding affinity, low immunogenicity and toxicity, and ease in synthesis with negligible batch-to-batch variation. Aptamers can specifically bind to the targets ranging from small molecules to complex structures, making them suitable for a myriad of diagnostic and therapeutic applications. In analytical scenarios, aptamers are used as molecular probes instead of antibodies. They have the potential in the detection of biomarkers, microorganisms, viral agents, environmental pollutants, or pathogens. For therapeutic purposes, aptamers can be further engineered with chemical stabilization and modification techniques, thus expanding their serum half-life and shelf life. A vast number of antagonistic aptamers or aptamer-based conjugates have been discovered so far through the in vitro selection procedure. However, the aptamers face several challenges for its successful clinical translation, and only particular aptamers have reached the marketplace so far. Aptamer research is still in a growing stage, and a deeper understanding of nucleic acid chemistry, target interaction, tissue distribution, and pharmacokinetics is required. In this review, we discussed aptamers in the current diagnostics and theranostics applications, while addressing the challenges associated with them. The report also sheds light on the implementation of aptamer conjugates for diagnostic purposes and, finally, the therapeutic aptamers under clinical investigation, challenges therein, and their future directions.

15.
Brief Funct Genomics ; 17(5): 319-328, 2018 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-29912293

RESUMO

The clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system uses single-guide RNAs for genome editing, making it a simple, robust, powerful tool for targeted gene mutagenesis, knockout and knock-in/replacement, as well as transcriptional regulation. Here, we review the working principles, components and potential modifications of CRISPR/Cas9 for efficient single and multiplex gene editing in plants. We also describe recent work that has used CRISPR/Cas9 to improve economically important traits in crop plants. Although the apparent ease of CRISPR/Cas9-mediated editing may make it appear as though scientists are merely playing with plant genomes, the combined power of CRISPR/Cas9 has enabled vital research to be completed in the battle toward optimization and adaptation of crop species, permitting crucial advances to be achieved in crop improvement.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Produtos Agrícolas/genética , Genoma de Planta , Plantas/genética , Edição de Genes
16.
Sci Rep ; 7(1): 15662, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29142238

RESUMO

Soil salinization and degradation is one of the consequences of climate change. Identification of major salt tolerance genes and marker assisted selection (MAS) can accelerate wheat breeding for this trait. We genotyped 154 wheat F2 lines derived from a cross between salt tolerant and susceptible cultivars using the Axiom Wheat Breeder's Genotyping Array. A high-density linkage map of 988 single nucleotide polymorphisms (SNPs) was constructed and utilized for quantitative trait loci (QTL) mapping for salt tolerance traits and mineral concentrations under salinity. Of 49 mapped QTLs, six were for Na+ exclusion (NAX) and two QTLs (qSNAX.2 A.1, qSNAX.2 A.2) on chromosome 2 A coincided with a reported major NAX QTL (Nax1 or HKT1;4). Two other major NAX QTLs were mapped on 7 A, which contributed 11.23 and 18.79% of the salt tolerance respectively. In addition to Ca+2 and Mg+2 QTLs, twenty-seven QTLs for tissue Phosphorus, Zinc, Iron, Manganese, Copper, Sulphur and Boron concentrations under salinity were also mapped. The 1293 segregating SNPs were annotated/located within genes for various ion channels, signalling pathways, transcription factors (TFs), metabolic pathways and 258 of them showed differential expression in silico under salinity. These findings will create new opportunities for salt tolerance breeding programs.


Assuntos
Locos de Características Quantitativas/genética , Tolerância ao Sal/genética , Oligoelementos/metabolismo , Triticum/genética , Mapeamento Cromossômico , Ligação Genética/genética , Genótipo , Micronutrientes/genética , Polimorfismo de Nucleotídeo Único/genética , Salinidade , Plântula/genética , Plântula/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
17.
Rep Pract Oncol Radiother ; 22(3): 212-216, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28461785

RESUMO

BACKGROUND: Peripheral or scatter dose harms neighbouring normal tissues during administration of dose to cancerous tissues, therefore, knowledge of peripheral dose is an important consideration in radiotherapy. AIM: In present study, absorbed dose measurements in a water phantom were performed for three field sizes, 7 × 7 cm2, 10 × 10 cm2 and 15 × 15 cm2. MATERIALS AND METHODS: For each field size, dose was measured at six depths below the front surface of the water phantom; 2.5-15 cm with an interval of 2.5 cm. Measurements were made at equal transverse distances along the horizontal axis, from 1 cm to 6 cm, on both sides of the central beam axis and normalized with central axis dose of each field. All measurements were made at the source to surface distance of 100 cm. RESULTS: Variation of peripheral dose with lateral distance was analysed and an appropriate parametric equation for each field size and depth was constructed. CONCLUSIONS: The peripheral radiation dose showed a strong dependence on field size and distance from field boundary.

18.
Biosens Bioelectron ; 81: 280-286, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26971274

RESUMO

In this report, a dual-excitation sensing method was developed using aptamer-functionalized quantum dots and upconverting nanoparticles, exhibiting Stokes and anti-Stokes type excitation profiles, respectively. Conjugation of the aptamer-functionalized luminescent nanoparticles with the magnetic beads, comprising short DNA sequences that were partially complementary to the aptamer sequences, enabled facile separation of the analyte-free conjugates for fluorescent measurement. UV-Visible spectroscopy, Circular Dichroism spectroscopy, Dynamic Light Scattering and Polyacrylamide Gel Electrophoresis techniques were used to characterize the aptamer probes developed. The target-specific luminescent conjugates were applied for multiplex detection of model food pathogens, Salmonella typhimurium, and Staphylococcus aureus, in which the fluorescent emission spectra were obtained under UV excitation at 325nm for quantum dots and NIR excitation at 980nm for upconverting nanoparticles, respectively. The dual-excitation strategy was aimed to minimize cross-talk between the luminescent signals for multiplexed detection, and yielded limit of detection values of 16 and 28cfumL(-1) for Staphylococcus aureus, and Salmonella typhimurium, respectively. By employing a greater number of quantum dots and upconverting nanoparticles with non-overlapping fluorescent emissions, the proposed methodology might be exploited further to detect several analytes, simultaneously.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Microbiologia de Alimentos , Nanopartículas/química , Pontos Quânticos/química , Salmonella typhimurium/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Humanos , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Infecções por Salmonella/microbiologia , Infecções Estafilocócicas/microbiologia
19.
Data Brief ; 9: 1175, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28050586

RESUMO

[This corrects the article DOI: 10.1016/j.dib.2015.09.050.].

20.
Front Plant Sci ; 6: 1012, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26635838

RESUMO

Drought being a yield limiting factor has become a major threat to international food security. It is a complex trait and drought tolerance response is carried out by various genes, transcription factors (TFs), microRNAs (miRNAs), hormones, proteins, co-factors, ions, and metabolites. This complexity has limited the development of wheat cultivars for drought tolerance by classical breeding. However, attempts have been made to fill the lost genetic diversity by crossing wheat with wild wheat relatives. In recent years, several molecular markers including single nucleotide polymorphisms (SNPs) and quantitative trait loci (QTLs) associated with genes for drought signaling pathways have been reported. Screening of large wheat collections by marker assisted selection (MAS) and transformation of wheat with different genes/TFs has improved drought signaling pathways and tolerance. Several miRNAs also provide drought tolerance to wheat by regulating various TFs/genes. Emergence of OMICS techniques including transcriptomics, proteomics, metabolomics, and ionomics has helped to identify and characterize the genes, proteins, metabolites, and ions involved in drought signaling pathways. Together, all these efforts helped in understanding the complex drought tolerance mechanism. Here, we have reviewed the advances in wide hybridization, MAS, QTL mapping, miRNAs, transgenic technique, genome editing system, and above mentioned functional genomics tools for identification and utility of signaling molecules for improvement in wheat drought tolerance.

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