The generation of electricity by dissociating water into H3O+ and OH– ions through a hydroelectric cell (HEC) without liberating any toxic waste has achieved a groundbreaking feat. Nanoporous ...magnesium-doped SnO2 and cobalt-doped SnO2 materials have been prepared via a novel sol–gel method. The X-ray diffraction patterns of Mg-doped SnO2 and Co-doped SnO2 completely match with those of pure SnO2, which confirms the interstitial substitution of Mg and Co in the pristine SnO2. The results shown by Brunauer–Emmett–Teller theory curves illustrate the surface area of Mg-doped SnO2 and Co-doped SnO2 to be 46.22 and 46.81 m2/g, respectively, with their pore radii being ∼3 nm. The synthesized nanoparticles were pressed into square pellets of area 4.08 cm2. A zinc electrode was pasted on one side of each pellet and silver was painted on the other side to develop the HECs. The fabricated HECs of Mg-doped SnO2 and Co-doped SnO2 with 4.08 cm2 area deliver short-circuit current, open-circuit voltage, and off-load output power of 41.69 mA, 0.787 V, and 32.81 mW and 77.52 mA, 0.454 V, and 35.19 mW, respectively. Cyclic voltammetry of both materials exhibited cathodic and anodic peaks in relation to the redox reactions taking place at Zn and silver electrodes. Nyquist curves of both HECs in the wet state confirm the ionic diffusion of split H3O+ and OH– ions as compared to the dry state. An off-load output power of 35.19 mW delivered by the HEC of Co-doped SnO2 with 4.08 cm2 area is quite promising and has great potential to replace other green energy sources.
Objective: The present study aims to evaluate aims to assess the knowledge, attitude, and practice of primiparous mothers in the immediate postpartum period regarding breastfeeding techniques which ...will be helpful in forming awareness and training programs. Materials and Methods: A cross-sectional survey was used. A total of 120 primiparous mothers with a mean age of 24.92 years participated in the survey and filled the questionnaire related to the knowledge, attitude, and practice of techniques of breastfeeding. Results: Results revealed that 48.3% of new mothers were not aware of the correct techniques to initiate breastfeeding, whereas 68.3% of subjects reported that during latching, the baby's upper and lower lip should be everted. The majority of new mothers were aware of breastfeeding techniques with some misconceptions as in our culture, most of the breastfeeding information passed from generation to generation. Conclusion: The level of awareness about feeding skills among primiparous mothers can be further improved by antenatal counseling or training from health-care workers during the gestational period. This will further help new mothers to educate and will provide adequate information which will decrease the myths.
Aphids constitute a large group of Hemipterans that use their slender stylets to tap into the sieve elements of plants from which they consume copious amounts of phloem sap, thus depriving the plant ...of photoassimilates. Some aphids also transmit viral diseases of plants.
Sülzer, commonly known as the green peach aphid (GPA), which is a polyphagous insect with a host range that covers 50 plant families, is considered amongst the top 3 insect pest of plants. The interaction between
and the GPA is utilized as a model pathosystem to study plant-aphid interaction. Here we describe the protocol used in our laboratories for rearing the GPA, and no-choice and fecundity bioassays to study GPA performance on
. In addition, we describe the procedure for the electrical penetration graph (EPG) technique to monitor feeding behavior of the GPA on
.
Lead-free magnetoelectric composites (1−
x
)K
0.5
Na
0.5
NbO
3
—(
x
)BaFe
12
O
19
(
x
= 30, 40, and 50 wt%) are synthesized using solid state reaction method. X-ray diffraction (XRD) patterns confirm ...formation of diphase composites. Field emission scanning electron microscopy (FE-SEM) gives information about grain size, connectivity, and microstructure of constituent phases. Dielectric parameters of composite samples are studied as a function of temperature and the transition temperatures corresponding to both the constituent phases are observed in the composite samples. Dielectric constant has been found to decrease with addition of ferrite. Room temperature multiferroic behaviour has been confirmed using
P
-
E
and
M
-
H
hysteresis loops and magnetoelectric measurement. Polarization is found to decrease; however, magnetization increases with ferrite weight percentage. The highest
α
ME
of 4.08 mV/(cm·Oe) is obtained for
x
= 30 wt% composite and it is realized that ferrite content significantly affects magnetoelectric behaviour.
In response to elevated temperatures, plants alter the activities of enzymes that affect lipid composition. While it has long been known that plant leaf membrane lipids become less unsaturated in ...response to heat, other changes, including polygalactosylation of galactolipids, head group acylation of galactolipids, increases in phosphatidic acid and triacylglycerols, and formation of sterol glucosides and acyl sterol glucosides, have been observed more recently. In this work, by measuring lipid levels with mass spectrometry, we confirm the previously observed changes in Arabidopsis thaliana leaf lipids under three heat stress regimens. Additionally, in response to heat, increased oxidation of the fatty acyl chains of leaf galactolipids, sulfoquinovosyldiacylglycerols, and phosphatidylglycerols, and incorporation of oxidized acyl chains into acylated monogalactosyldiacylglycerols are shown. We also observed increased levels of digalactosylmonoacylglycerols and monogalactosylmonoacylglycerols. The hypothesis that a defect in sterol glycosylation would adversely affect regrowth of plants after a severe heat stress regimen was tested, but differences between wild-type and sterol glycosylation-defective plants were not detected.
Systemic acquired resistance (SAR) is an inducible defense mechanism that is activated throughout the plant, subsequent to localized inoculation with a pathogen. The establishment of SAR requires ...translocation of an unknown signal from the pathogen-inoculated leaf to the distal organs, where salicylic acid-dependent defenses are activated. We demonstrate here that petiole exudates (PeXs) collected from Arabidopsis leaves inoculated with an avirulent (Avr) Pseudomonas syringae strain promote resistance when applied to Arabidopsis, tomato (Lycopersicum esculentum) and wheat (Triticum aestivum). Arabidopsis FATTY ACID DESATURASE7 (FAD7), SUPPRESSOR OF FATTY ACID DESATURASE DEFICIENCY1 (SFD1) and SFD2 genes are required for accumulation of the SAR-inducing activity. In contrast to Avr PeX from wild-type plants, Avr PeXs from fad7, sfd1 and sfd2 mutants were unable to activate SAR when applied to wild-type plants. However, the SAR-inducing activity was reconstituted by mixing Avr PeXs collected from fad7 and sfd1 with Avr PeX from the SAR-deficient dir1 mutant. Since FAD7, SFD1 and SFD2 are involved in plastid glycerolipid biosynthesis and SAR is also compromised in the Arabidopsis monogalactosyldiacylglycerol synthase1 mutant we suggest that a plastid glycerolipid-dependent factor is required in Avr PeX along with the DIR1-encoded lipid transfer protein for long-distance signaling in SAR. FAD7-synthesized lipids provide fatty acids for synthesis of jasmonic acid (JA). However, co-infiltration of JA and methylJA with Avr PeX from fad7 and sfd1 did not reconstitute the SAR-inducing activity. In addition, JA did not co-purify with the SAR-inducing activity confirming that JA is not the mobile signal in SAR.
Myzus persicae, commonly known as green peach aphid (GPA), is a sap-sucking insect with a broad host range. Arabidopsis thaliana responds to GPA infestation with elevated expression of the ...PHYTOALEXIN DEFICIENT4 (PAD4) gene. Previously, we had demonstrated that the loss of PAD4 gene function compromises Arabidopsis resistance to GPA. In contrast, a mutation in the Arabidopsis SUPPRESSOR OF SALICYLIC ACID INSENSITIVITY2 (SSI2) gene, which encodes a desaturase involved in lipid metabolism, resulted in hyper-resistance to GPA. We demonstrate here that PAD4 is required for the ssi2-dependent heightened resistance to GPA. Based on electrical monitoring of insect behavior and bioassays in which the insect was given a choice between the wild type and the ssi2 mutant, it is concluded that the ssi2-conferred resistance is not due to deterrence of insect settling or feeding from the phloem of the mutant. Instead, hyper-resistance in the ssi2 mutant results from heightened antibiosis that curtails insect reproduction. Petiole exudates collected from uninfested ssi2 plants contain elevated levels of an activity that interferes with aphid reproduction in synthetic diets. PAD4 was required for the accumulation of this antibiotic activity in petiole exudates, supporting the role of PAD4 in phloem-based resistance. Because PAD4 expression is not elevated in the ssi2 mutant, we suggest that basal PAD4 expression contributes to this antibiosis.
In a screen for suppressors of npr1-5-based salicylic acid (SA) insensitivity, we isolated a semidominant gain-of-function mutation, designated ssi4, that confers constitutive expression of several ...PR (pathogenesis-related) genes, induces SA accumulation, triggers programmed cell death, and enhances resistance to bacterial and oomycete pathogens. Through map-based cloning, ssi4 was identified and found to encode a putative protein belonging to the TIR-NBS-LRR (Toll Interleukin1 Receptor-Nucleotide Binding Site-Leu-Rich Repeat) class of R (resistance) proteins. Comparison between ssi4 and the corresponding wild-type sequence revealed a single amino acid substitution in the NBS. Epistasis analysis indicated that SA and EDS1 are required for ssi4-induced PR-1 expression and enhanced disease resistance; they also are required for the increased accumulation of SSI4 and EDS1 transcripts detected in the ssi4 mutant. Although high levels of ssi4 transcripts correlate with the appearance of the mutant phenotype, overexpression of the wild-type SSI4 gene failed to induce stunting, spontaneous lesion formation, or increased PR-1 expression associated with the ssi4 mutation. Thus, the ssi4 phenotype does not appear to be caused by overexpression of this R gene; rather, we propose that the NBS substitution generates a constitutively activated R protein. Furthermore, because SA treatment induced the expression of SSI4 and the closely related TIR-NBS-LRR genes RPP1 and RPS4 but had little effect on the expression of the coiled-coil NBS-LRR genes RPM1 and RPS2, we suggest that SA not only functions as a critical signal for downstream resistance events but also upregulates the expression of certain R genes.
Fusarium graminearum causes Fusarium head blight (FHB) disease in wheat and other cereals. F. graminearum also causes disease in Arabidopsis thaliana. In both Arabidopsis and wheat, F. graminearum ...infection is limited by salicylic acid (SA) signaling. Here, we show that, in Arabidopsis, the defense regulator EDS1 (ENHANCED DISEASE SUSCEPTIBILITY1) and its interacting partners, PAD4 (PHYTOALEXIN-DEFICIENT4) and SAG101 (SENESCENCE-ASSOCIATED GENE101), promote SA accumulation to curtail F. graminearum infection. Characterization of plants expressing the PAD4 noninteracting eds1(L262P) indicated that interaction between EDS1 and PAD4 is critical for limiting F. graminearum infection. A conserved serine in the predicted acyl hydrolase catalytic triad of PAD4, which is not required for defense against bacterial and oomycete pathogens, is necessary for limiting F. graminearum infection. These results suggest a molecular configuration of PAD4 in Arabidopsis defense against F. graminearum that is different from its defense contribution against other pathogens. We further show that constitutive expression of Arabidopsis PAD4 can enhance FHB resistance in Arabidopsis and wheat. Taken together with previous studies of wheat and Arabidopsis expressing salicylate hydroxylase or the SA-response regulator NPR1 (NON-EXPRESSER OF PR GENES1), our results show that exploring fundamental processes in a model plant provides important leads to manipulating crops for improved disease resistance.
RNA interference has revolutionized our ability to study the effects of altering the expression of single genes in mammalian (and other) cells through targeted knockdown of gene expression. In this ...report we describe a web-based computational tool, siRNA Information Resource (sIR), which consists of a new open source database that contains validation information about published siRNA sequences and also provides a user-friendly interface to design and analyze siRNA sequences against a chosen target sequence.
The siRNA design tool described in this paper employs empirically determined rules derived from a meta-analysis of the published data; it uses a weighted scoring system that determines the optimal sequence within a target mRNA and thus aids in the rational selection of siRNA sequences. This scoring system shows a non-linear correlation with the knockdown efficiency of siRNAs. sIR provides a fast, customized BLAST output for all selected siRNA sequences against a variety of databases so that the user can verify the uniqueness of the design. We have pre-designed siRNAs for all the known human genes (24,502) in the Refseq database. These siRNAs were pre-BLASTed against the human Unigene database to estimate the target specificity and all results are available online.
Although most of the rules for this scoring system were influenced by previously published rules, the weighted scoring system provides better flexibility in designing an appropriate siRNA when compared to the un-weighted scoring system. sIR is not only a comprehensive tool used to design siRNA sequences and lookup pre-designed siRNAs, but it is also a platform where researchers can share information on siRNA design and use.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK