Soil salinity is among the leading environmental stresses affecting global agriculture, causing billions of dollars in crop damages every year. Regardless of the cause, ion toxicity, water deficit, ...or nutritional imbalance, high salinity in the root zone severely impedes normal plant growth and development, resulting in reduced crop productivity or crop failure. Development of salt-tolerant cultivars is an attractive and economical approach to solving this problem. Although several salt-tolerant plant genotypes have been developed through transgenic approaches, often they have failed or exhibited limited success under field saline conditions. This is due to several reasons, including the fact that plant growth and development under saline conditions in the field is often influenced by cumulative effects of multiple environmental stresses and genetic factors, which may not have been considered during the development of salt-tolerant transgenic plants. Adoption of inappropriate screening techniques or selection criteria may also lead to selection of genotypes that may not be stress tolerant in a real sense. In most plant species, salt tolerance is a genetically complex trait, often modulated by multiple biosynthetic and signaling pathways. Cross-talks among various stress-controlling pathways have been observed under salt stress, many of which are regulated by transcription factors. Thus, a comprehensive knowledge of the up- and downregulating genes under salt-stress is necessary, which would provide a better understanding of the interactions among pathways in response to salt stress. Attaining such knowledge is a good step toward successful development of salt-tolerant crop cultivars. To this end, DNA microarray technology has been employed to study expression profiles in different plant species and at varying developmental stages in response to salt stress. As a result, large-scale gene expression profiles under salt stress are now available for many plant species, including Arabidopsis, rice, barley, and ice plant. Examinations of such gene expression profiles will help understand the complex regulatory pathways affecting plant salt tolerance and potentially functional characterization of unknown genes, which may be good candidates for developing plants with field salt tolerance. In this article, we review and discuss the current knowledge of plant salt tolerance and the extent to which expression profiling has helped, or will help, a better understanding of the genetic basis of plant salt tolerance. We also discuss possible approaches to improving plant salt tolerance using various tools of biotechnology.
•The stability of CoxFe(2-x)O3 nanoparticles enhances.•Energy losses increases.•Anisotropy of NP is high.
This paper is dedicated to investigate the effect of Co2+ ions in magnetite Fe3O4 ...nano-particles with stoichiometric formula CoxFe3-xO4 where (x=0, 0.05, 0.1 and 0.15) prepared by co-precipitation method. The structural, thermal, morphological, magnetic and optical properties of magnetite and Co2+ doped magnetite nanoparticles have been carried out using X-ray Diffractometer, Fourier Transform Infrared Spectroscopy, Themogravimetric Analysis, Scanning Electron Microscopy, Vibrating Sample Magnetometer (VSM) and UV–Vis Spectrometer (UV–Vis) respectively. Structural analysis verified the formation of single phase inverse spinel cubic structure with decrease in lattice parameters due to increase in cobalt content. FTIR analysis confirms the single phase of CoxFe3-xO4 nanoparticles with the major band at 887cm−1, which might be due to the stretching vibrations of metal-oxide bond. The DSC results corroborate the finding of an increase in the maghemite to hematite phase transition temperature with increase in Co2+ content. The decrease in enthalpy with increase in Co2+ concentration attributed to the fact that the degree of conversion from maghemite to hematite decrease which shows that the stability increases with increasing Co2+ content in B-site of Fe3O4 structure. SEM analysis demonstrated the formation of spherical shaped nanoparticles with least agglomeration. The magnetic measurements enlighten that the coercivity and anisotropy of CoxFe3-xO4 nanoparticles are significantly increased. From UV–Vis analysis it is revealed that band gap energy increases with decreasing particle size. This result has a great interest for magnetic fluid hyperthermia application (MPH).
Non-singular Kruskal-like coordinates of some black holes space-times in f (R) gravity are presented in this research paper, and are also removed by establishing Kruskal-Szekeres coordinates for ...Non-extremal case. Carter-like coordinates can also be built for its extreme case.
Abstract Environmental stress caused by pollution is often assessed by diversity of macro-invertebrate species in specific aquatic habitat. To find out seasonal fluctuations in various ...macro-invertebrates communities and different water quality parameters of River Zhob, a research trial was conducted on River Zhob, Balochistan. Samples of macro-invertebrates and water were taken from four different stations of River Zhob. A total 18 taxa of various macro-invertebrates were identified from the area. Phylum Arthropoda constitute 94.8% of the total population followed by Mollusca (3.6%) and Annelida (1.4%). A large number of arthropods were belonged to order Diptera (1148), while the order Trichoptera was stood second with respect to macro-invertebrate´s number (441). The maximum numbers of macro-invertebrates were observed in the month of January. All physico-chemical parameters of River Zhob such as air temperature, water temp, pH, dissolved oxygen (DO) and total dissolved solids (TDS) were within the range, suitable for the healthy growth of macro-invertebrates. Diversified populations of various macro-invertebrates confirm good ecological condition of environment and water in the studied site especially ample concentration of DO in River. The documented data on macro-invertebrates in studied site will provide a baseline for future research.
Resumo O estresse ambiental causado pela poluição é frequentemente avaliado pela diversidade de espécies de macroinvertebrados em habitats aquáticos específicos. Para descobrir as flutuações sazonais em várias comunidades de macroinvertebrados e diferentes parâmetros de qualidade da água do rio Zhob, foi realizado um teste de pesquisa no rio Zhob, Baluchistão. Amostras de macroinvertebrados e água foram retiradas de quatro estações diferentes do rio Zhob. Um total de 18 táxons de vários macroinvertebrados foram identificados na área. O filo Arthropoda constitui 94,8% da população total, seguido por Mollusca (3,6%) e Annelida (1,4%). Um grande número de artrópodes pertencia à ordem Diptera (1148), enquanto a ordem Trichoptera ocupava o segundo lugar em número de macroinvertebrados (441). Os números máximos de macroinvertebrados foram observados no mês de janeiro. Todos os parâmetros físico-químicos do rio Zhob, como temperatura do ar, temperatura da água, pH, oxigênio dissolvido (OD) e sólidos dissolvidos totais (TDS), estavam dentro da faixa, adequada para o crescimento saudável de macroinvertebrados. Populações diversificadas de vários macroinvertebrados confirmam boas condições ecológicas do ambiente e da água no local estudado, especialmente a ampla concentração de DO no rio. Os dados documentados sobre macroinvertebrados no local estudado fornecerão uma linha de base para pesquisas futuras.
This article deals with q-starlike functions associated with conic domains, defined by Janowski functions. It generalizes the recent study of q-starlike functions while associating it with the conic ...domains. Certain renowned coefficient inequalities in connection with the previously known ones have been included in this work.
The ever increasing interest in titanium oxide (titania) is motivated by its applications in solar cells, biomaterials and photo-catalytic activities. Nanocrystalline titania is preferred in these ...applications due to chemical stability, mechanical hardness, high refractive index and excellent transmission in the visible region. Titania exists in three different crystallographic phases i.e. anatase, rutile and brookite, amongst which brookite is the most difficult to synthesize. Anatase and rutile crystallize in tetragonal phase whereas brookite has orthorhombic phase. In the present work, titania nanoparticles are synthesized following sol–gel approach. TiCl
4
is used as precursor and ammonia as a gelation agent. pH of the sol is varied in the range of 1–11. Nanostructures and hollow core titania nanoparticles with mean diameter of 120 and 70 nm respectively have been synthesized without the use of any hard/soft template. At pH 1 the nanoparticles show amorphous behavior whereas increasing the pH induces crystallinity in nanoparticles. The presence of (020), (202) and (321) confirms the formation of pure brookite phase at a low temperature of 60 °C. The presence of absorption bands in fourier transform infrared spectroscopy in the range of 450–700 cm
−1
correspond to infrared active mode of Ti–O–Ti stretching indicating the formation of titania. Detailed Spectroscopic analyses indicate that these nanoparticles are highly transmitting in the visible and infrared region with band gap in the range of 2.96–3.03 eV. Cauchy Model used for fitting the experimental spectroscopic data gives a high value of refractive index with low extinction coefficient.
Around the globe, plastic has been entering the aquatic system and is ingested by organisms. Identification, optimal digestion method, and characterization of the polymers to trace sources are of ...growing importance. Hence, the present work investigated microplastics accumulation, digestion protocol efficiency, and characterization of polymers with FTIR analysis in the guts of five fishes (Lethrinus nebulosus, Rastrelliger kanagurta, Acanthopagrus arabicus, Otolithes ruber, and Euryglossa orientalis) from the Karachi coastal area, Arabian Sea. A total of 1154 microplastics (MPs) were ingested by 29 out of 33 fish species (87%). The highest average MP/fish was recorded in Otolithes ruber (54) and the lowest in Rastrelliger kanagurta (19.42). Microfibers were the most abundant shape with the highest numbers (35.52%) as compared to the rest of the MPs identified. Transparent microfibers were recorded as the highest in numbers followed by red, black, blue, and green. In this study, KOH with different concentrations and exposure times along with oxidizing agent hydrogen peroxide was tested (Protocols 3 and 4). Results showed these bases were highly efficient in obtaining optimal digestion of the samples. FTIR analysis confirmed that the majority of the polymers found in the fish guts were polyethylene and polypropylene. This study validated for the first time the presence of these polymers of plastic in marine fish from Pakistan.
Doping-induced tuning of host semiconductors properties offers an efficient way to realize the desired physical properties. In this study, we have synthesized pure and Co-doped SnS-diluted magnetic ...semiconductors with
x
Co
= 0.00–0.10, by employing a very simple and low-cost chemical co-precipitation technique. The structural properties, determined through X-ray diffraction, have confirmed single-phase orthorhombic structure and have depicted nano-crystallites. Near-edge X-ray absorption fine structure spectroscopy has revealed a Co-doping-induced shift in the absorption edge towards lower energy, indicating a change in the Co oxidation state. Surface morphology observed through scanning electron microscopy indicates nano-structured surface. Dielectric properties measured by impedance analyzer (LCR meter) in the frequency range 1 kHz–20 MHz depict that grown materials respond to the electromagnetic radiations suggesting potential device applications. Complex impedance spectroscopy illustrates the dominance of grain resistance. The magnetic properties observed by vibrating sample magnetometer reveal room temperature ferromagnetism, and Co ions inducing tuning of the ferromagnetism suggests potential applications in the data storage devices.
Among the various multiferroic materials bismuth iron oxide is a promising candidate due to its relatively high antiferromagnetic Neel temperature and high ferroelectric Curie temperature as compared ...to all other multiferroic materials. However, synthesis of phase pure BiFeO
3
is extremely difficult due to the volatile nature of Bi
2
O
3
that leads to bismuth-deficient phases and if excess of bismuth is employed it gives rise to bismuth rich phases. Moreover, the synthesis of phase pure BiFeO
3
requires high temperature annealing in the range of 400–700 °C. In order to overcome these difficulties, we here report microwave-assisted sol–gel synthesis of phase pure BiFeO
3
nanoparticles. In the present study, power of microwaves is varied as 136, 264, 440, 616 and 800 W. XRD results show formation of phase pure BiFeO
3
with rhombohedrally distorted perovskite structure at 264, 440 and 800 W. Crystallite size decreases to 21 nm with the increase in microwave power to 800 W. The presence of absorption bands at 470 and 580 cm
−1
in FTIR spectra, corresponding to FeO
6
and BiO
6
, indicate the formation of pure BiFeO
3
phase. BiFeO
3
nanoparticles show high dielectric constant (135 at 1 kHz) at 264 W. SEM images show the formation of spherical and cubic nanoparticles in the range of 100–150 nm with microwave powers of 136–440 W. Increasing the microwave power to 616 W gives spherical nanoparticles with sizes of 60 nm while further increasing the microwave power to 800 W results in nanoneedles with diameter of 30 nm. Ferromagnetic behavior, instead of antiferromagnetic nature of BiFeO
3
, is observed for the nanoparticles prepared at microwave power of 616 and 800 W. This demonstrates that microwave-assisted sol–gel technique gives phase pure BiFeO
3
nanoparticles using low power and less time, along with excellent ferromagnetic and dielectric properties as compared to conventional heating method.
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