Small RNAs in Plant Response to Abiotic Stress

Small noncoding (nc) RNAs (sRNAs) are the important posttranscriptional regulatory factors in gene regulatory networks. They are involved in many important processes of plant development and stress responses. Increasingly research data reveal that microRNAs (miRNAs), heterochromatic small interfering RNAs (hc-siRNAs), trans-acting small interfering RNAs (ta-siRNAs), natural antisense small interfering RNAs (nat-siRNAs), repeat-associated small interfering RNAs (ra-siRNAs), and the piwi-interacting RNAs (piRNAs) are involved in heat stress, salt stress, cold stress, and drought stress, which are found in metazoans. Some small RNAs are required for plant thermotolerance and salt tolerance. These findings facilitate our investigation of the genetic basis of plant adaptability to various environmental stresses and the genetic manipulation of plant tolerance to many abiotic stresses. This chapter highlights the recent advances in understanding the crucial roles of sRNAs in plant responses to heat, drought, salinity, and cold and proposes the potential technologies and strategies used to identify abiotic-stress-regulated sRNAs in addition to the recent advances and methods for validation and analysis of their target genes

<em>Kelussiaodoratissima</em> Mozaff.as a rich source of essential fatty acids andphthalides

Abstract Introduction: The present study is the first assessment of the fatty acids of leaf and essential oil compositions of new three habitats of aerial parts of K. odoratissima. Methods: The aerial parts of K. odoratissima from the three habitats were dried. The essential oils were obtained by hydrodistillation for 3 h in a Clevenger-type apparatus, then the analysis of the components was carried out using gas chromatography&ndash;mass spectrometry. To study the oil yield and fatty acids, the dried leaves subjected to extraction in hexane by using Soxhlet Apparatus. To analyze fatty acids from the oil fractions by gas chromatography technique, the oil was subjected to transesterification to obtain the fatty acid methyl esters, which, were dissolved in hexane and subjected to GC analysis. Results: According to the results, a total of 43 components, the major constitutes of essential oil compositions were (Z)-Ligustilide (76.45), Unknown-A (4.47), (E)-Ligustilide (2.57), (Z)-Butylidene phthalide (2.37), 5-pentyl cyclohexa-1,3-diene (1.57) and Kessane (0.77) in K. odoratissima. The sixteen fatty acids were separated &nbsp;from the oil (5 yield per 100 g dry matter). Linoleic acid (25.46), &alpha;-Linolenic acid (16.66), Palmitic acid (11.92), Oleic acid (9.33), Stearic acid (4.72), Petroselinic acid (2.53), Arachidonic acid (2.51) and Erucic acid (1.76) were major fatty acids. Conclusion: Generally, K. odoratissima is a rich source of essential fatty acids and phthalide derivatives, specially (Z)-ligustilide. This study was presented valuable information about the phytochemical properties, which can be useful for the future researches on the pharmacological effects of K. odoratissima

In vitro Culture of Several Rice Cultivars

Tissue culture methods have been established to regenerate certain rice (Oryza sativa L) cultivars, but regeneration of the rice cultivars widely grown in Arkansas has not been reported. This study has established an in vitroculture for the rice cultivars \u27Nortai\u27, \u27Starbonnet\u27, \u27Mars\u27, Tebonnet\u27, \u27Newbonnet\u27, and \u27Lemont\u27. Callus was induced in the dark at either 20 or 28 C from dehusked seeds cultured on Murashige and Skoog (MS) medium (Murashige and Skoog, 1962) containing 40 g L^-1 sucrose, 10 g L^1 agar, 0.5, 1.0, or 2.0 mg L^-1 1 2,4-dichlorophenoxyacetic acid (2,4-D) and adjusted to pH 5.7. After four weeks the calli were weighed, transferred onto MS medium containing no 2,4-D, and maintained in a 1 2-h photoperiod (65 uE m^-2 s^-1) at 25 ± 2 C to induce plant regeneration. Callus production was best when cultured on a medium containing 1.0 mg L^-1 2,4-D and incubated at 28 C. Plant regeneration was observed two to four weeks later. The percentage of calli regenerating platlets varied with the cultivar and the callus induction treatment. Callus induction at 20 C on a medium with a 2,4-D level less than 2.0 mg L^-1 enhanced the regenerability of most cultivars. Regenerates were transplanted to soil and grow normally to maturity. This system can be helpful in improving rice cultivars with tissue culture techniques such as somaclonal variant selection and somatic hybridization

Potential of Iranian wild barley (Hordeum vulgare ssp. spontaneum) in breeding for drought tolerance

The vast genetic resources of wild barley (Hordeum vulgare ssp. spontaneum, hereafter WB) may hold unique assets for improving barley (H. vulgare ssp. vulgare) cultivars for drought stress. To evaluate genetic potential and characterization of variation among a diverse collection of barley and WB genotypes, mostly originated from Iran, a field experiment was performed under three moisture environments (control, mild and intense drought stress) during two years (2012–2014). Considerable variation was observed among the wild and cultivated genotypes for drought tolerance and agronomic traits. Principal component analysis (PCA) grouped genotypes studied into three groups (WB, two-row barley and sixrow barley groups). However, Iranian and foreign WB genotypes were not completely separated, showing a high variation within both gene pools. The high significance of genotype by environment interaction, confirms importance of using accurate target environments for drought stress breeding. A number of WB genotypes with the highest values of the number of tillers, number of seed per spike, seed weight, grain yield and yield stability index under stressed environments were identified as superior genotypes. Most of these genotypes originate from Iran, highlighting the importance of this germplasm in barley breeding

Golpayegan metamorphic complex (Sanandaj–Sirjan Zone, Iran) as evidence for Cadomian back-arc magmatism: structure, geochemistry and isotopic data

The Golpayegan metamorphic complex is located in the Sanandaj-Sirjan Zone, Iran. This complex consists of various metamorphic rocks including schists, marbles, slates, gneisses, and amphibolites, most of them have Neoproterozoic age. The presence of structures such as sigma fabrics, boudinage, folded boudinage and interfering fold patterns indicates the occurrence of more than two deformation phases in the Golpayegan metamorphic complex. The measurement of strain intensity in the folds indicated deep immersion of structures and old Precambrian settings that had been influenced by orogenic events in the Neoproterozoic. These deformed rocks were exposed during extensional movements and, subsequently, sheared. The results based on field works shown geochemical relations and initial εNd(600 Ma) values of amphibolites in three sampling points located in Golpayegan region manifested that the protolith of the first (a') and second (b') sampling points had mantle origin (ortho-amphibolite), whilst protolith of the third (c') sampling point had sedimentary origin (para-amphibolite). Geochemically, the Golpayegan ortho-amphibolites showed subalkaline basalt-basaltic andesite compositions of tholeiitic affinity. The negative anomalies of Nb and Ti relative to Pb, La, and Ce in the primitive mantle-normalized spider-diagram and εNd(600 Ma) values revealed the subduction environment for ortho-amphibolites. The ortho-amphibolites exhibited the intermediate chemistry between the normal mid-ocean ridge basalt and island-arc tholeiitic basalt. Enrichment in large ion lithophile elements (LILE), light rare earth elements (LREE), and relative depletion in high field strength elements (HFSE) suggest the back-arc basin setting for the Golpayegan ortho-amphibolites. The primitive magma of the ortho-amphibolites was produced by 8–20% melting of spinel lherzolite. According to the Neoproterozoic age of the Golpayegan ortho-amphibolites and their relationship with the Golpayegan granitic gneiss (596‒578 Ma), it shows that they can be related to the Cadomian back-arc basin in the north of Peri-Gondwana at the Neoproterozoic. The high values of 87Sr/86Sr (0.708450‒0.714986) interpreted as result of seawater hydrothermal alteration.publishe

Social Alignment Contagion in Online Social Networks

Researchers have already observed social contagion effects in both in-person and online interactions. However, such studies have primarily focused on users’ beliefs, mental states, and interests. In this article, we expand the state of the art by exploring the impact of social contagion on social alignment, i.e., whether the decision to socially align oneself with the general opinion of the users on the social network is contagious to one’s connections on the network or not. The novelty of our work in this article includes: 1) unlike earlier work, this article is among the first to explore the contagiousness of the concept of social alignment on social networks; 2) our work adopts an instrumental variable approach to determine reliable causal relations between observed social contagion effects on the social network; and 3) our work expands beyond the mere presence of contagion in social alignment and also explores the role of population heterogeneity on social alignment contagion. Based on the systematic collection and analysis of data from two large social network platforms, namely, Twitter and Foursquare, we find that a user’s decision to socially align or distance from social topics and sentiments influences the social alignment decisions of their connections on the social network. We further find that such social alignment decisions are significantly impacted by population heterogeneity

Investigation on tourmaline occurrence in the metamorphic complex in the north of Golpayegan, Sanandaj-Sirjan Zone

The occurrence of tourmaline in the metamorphic complex of the north of Golpayegan is observed within the granitoid mass and schists in contact with granitoid and marbles.Speaking of abundance, tourmaline is less frequently a minor mineral found in granites and granitic pegmatites as well as in low- to high-grade metamorphic rocks (Krmícek et al., 2020). The minerals of the tourmaline group can adjust their composition to adapt to varied settings, and therefore show a remarkable stability range in terms of pressure, temperature, fluid composition, and host rock composition (Van Hinsberg et al., 2011). Since tourmaline displays a negligible intra-crystalline diffusion, it can record the physical and chemical conditions of its setting and preserve this information in geological chronicles. Therefore, tourmaline accurately presents the composition of fluids and the melts from which it crystallized (Marks et al., 2013). Although tourmaline is common in many rocks, it is not common in metamorphosed carbonates (Krmícek et al., 2020).A petrographical and geochemical investigation of tourmalines in the north of Golpayegan was undertaken to know the formation mechanism of this mineral and to determine the differences between tourmalines crystallized at the contact, in granitoid and tourmaline in marbles.Regional GeologyThe Golpayegan Metamorphic Complex is located in the Sanandaj-Sirjan Zone and the occurrence of tourmaline in this complex is observed in two locations. The first location is on the west side of Ochestan farm where tourmaline is found in three forms:1) In the granitoid mass (Gt); 2) In the amphibole schists (At) in contact with the granitoid mass, and 3) In the mica schists (Mt) in contact with the granitoid mass. The second area is in the north of Esfajerd where tourmaline occurs inside the marbles (Ct).MethodologyWith the completion of field reconnaissance and preparation of thin sections, a petrographic study was fulfilled to determine the texture and mineralogy of the minerals, and then, some samples were selected for electron microprobe analysis.PetrographyThe tourmaline in granitoid mass (Gt), appears as idiomorphic and coarse-grained without any inclusions. Micaschists (Mt) in contact with the granitoid mass are sieve-shaped or spongy. Inside the amphibole schists (At) in contact with the granitoid mass, it is idiomorphic without any inclusions.Tourmaline in marbles (Ct) is fine-grained and blue, which can be observed around biotites with corrosion marks, indicating its reaction with fluid.Tourmaline chemistryThe tourmalines in Ochestan granite-pegmatite (Gt) are of alkali tourmaline variety with schorl composition, enriched in aluminum, and points to the replacement of Al in the Y (R2) position. The substitution type of these tourmalines is Al(NaFe+2)-1 owing to the high amount of Fe versus Mg,The tourmalines in amphibole schist (At) are alkali tourmaline with schorl-dravite composition and the tourmalines in mica schist (Mt) are alkali tourmaline with dravite composition, and both types are characterized by insignificant amounts of aluminum. This demonstrates the replacement of Al in the position of Y (R2) has not occurred. Due to the change in Mg and Fe content, the At-type tourmalines benefit from both Al(NaFe+2)-1 and Al(NaMg)-1 substitution varieties. However, the substitutions of Mt-type tourmalines are mainly Al(NaMg)-1 due to the high content of Mg versus Fe. Indeed, Fe+3Al-1 substitution can be observed in both types of tourmaline.Tourmalines in marble (Ct) are of the alkaline type of dravite composition and rich in aluminum, which indicates the replacement of Al in the Y (R2) position. Their substitution is Al(NaMg)-1 due to the high content of Mg versus Fe.DiscussionThe composition of tourmaline in Gt is of schorl type (Fe/Fe+Mg= 0.89-0.91) and has an aluminum replacement in the Y position. The composition of tourmaline in Mt type is of dravite type (Fe/Fe+Mg= 0.45-0.47) and the composition of tourmaline in At type is of schorl-dravite type (Fe/Fe+Mg= 0.49-0.51), which, replacement of aluminum in the Y position does not occur in both types of tourmaline in schists. Consequently, hydrothermal tourmalines have less aluminum (i.e. At and Mt-type tourmalines), and tourmalines in the granite-pegmatite mass have much more aluminum (i.e. Gt-type tourmalines). Based on the values of Fe# (FeO/FeO+MgO), it is possible to determine the formation site of tourmalines. If the amount of Fe# in tourmaline is >0.8, it indicates the closed magmatic system, lack of fluids interference, and their contamination with Al-rich sediments. Meanwhile, if the ratio is 566°C biotite, and lower temperatures, Ct-type tourmaline is composed of biotites.AcknowledgmentThe authors are sincerely grateful to the Geology Department of Isfahan University for all their support

Sustainable Agriculture Reviews

 The Epichloë fungal endophytes that inhabit grasses have potentially large-scale consequences for macro- and micro-organisms and food chains in agriculture. Over 40 years of study on the benefits of symbiotic Epichloë fungal endophytes for host grasses, investigations have focused on the major agricultural species, tall fescue and perennial ryegrass. However, many other grass species remain to be evaluated for the effects of Epichloë endophytes. Animal toxicity due to accumulation of nitrogenous compounds, e.g. endophyte-dervived alkaloids, particularly in areas and periods under abiotic stress, still prevent widespread application of endophyte-infected grasses in agroecosystems. Here we review Epichloë endophyte-ecosystem relationships. The major points are: (1) Epichloë endophytes protect their host plants from vertebrate and invertebrate herbivory and allow plants to persist under water shortage, salinity, low light, mineral deficiencies and metal toxicity. Data suggests that the concentration of endophyte-derived anti-herbviore compounds increases with rising temperatures. This trend thus suggests that the strength of mutualistic interactions may increase in future climates with possible consequences for animal toxicity. (2) The benefits of endophyte infection for the host grass are context-dependent, varying with  environmental conditions, grass species and cultivar, and are also highly influenced by interactions between both host and endophyte genetic combinations. (3) The benefits of fungal endophytes extend to neighboring grass species with respect to their protection from diseases and herbivores. (4) Novel grass-endophyte associations that produce alkaloids reducing herbivory insects, but do not produce alkaloids that are toxic to grazing vertebrates have been found. Such associations are therefore useful to control plant pests and diseases.</p

Comparison of outcome following dacryocystorhinostomy with or without silicon stent appliance; a randomized clinical trial

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Evaluation of Vitamin D3 and D2 Stability in Fortified Flat Bread Samples During Dough Fermentation, Baking and Storage

Purpose: Vitamin D, a fat-soluble secosteroid, has a significant role in bone metabolism and helps calcium absorption in the body. Since vitamin D concentration is altered in fortified foods and dietary supplements, the actual amount of vitamin D may differ from the label value. Methods: In this study, the concentrations of vitamin D2 and D3 of fortified bread sample were analytically determined. For this purpose, dough or homogenized bread sample was saponified using potassium hydroxide solution (30%, w/v) at 80°C, and the saponified analytes were extracted into n-heptane followed by liquid-liquid extraction. Then n-heptane fraction was evaporated to dryness and the sample was reconstituted in methanol. The effect of different parameters was evaluated by one variable at one-time strategy. Results: The analytes concentrations were evaluated in dough fermentation, baking and storage steps. The effect of temperature in dough fermentation and baking was evaluated at the range of 5-30 and 200-250°C, respectively. Also, the fermentation time was studied in the range of 0-120 min. The analytes concentrations were followed for 1 to 5 days after baking. The results indicated that dough fermentation temperature has no significant effect on the concentration of the analytes. On the other hand, when the dough fermentation time and baking temperature are increased, the analytes concentrations are decreased. Also, the storage duration of the spiked bread samples decreased the analytes concentrations after one day. Conclusion: Based on the obtained results, baking the dough at high temperatures lead to decrease in vitamin levels