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71.

Background  

Mutations in the Shaker-like voltage-gated potassium channel Kv1.1 are known to cause episodic ataxia type 1 and temporal lobe epilepsy. Mice that express a malfunctional, truncated Kv1.1 (BALB/cByJ-Kv1.1 mceph/mceph ) show a markedly enlarged hippocampus and ventral cortex in adulthood.  相似文献   
72.
Biofortification of pulse crops with Zn and Fe is a viable approach to combat their widespread deficiencies in humans. Lentil (Lens culinaris Medik.) is a widely consumed edible crop possessing a high level of Zn and Fe micronutrients. Thus, the present study was conducted to examine the influence of foliar application of Zn and Fe on productivity, concentration, uptake and the economics of lentil cultivation (LL 931). For this, different treatment combinations of ZnSO4·7H2O (0.5%) and FeSO4·7H2O (0.5%), along with the recommended dose of fertilizer (RDF), were applied to the lentil. The results of study reported that the combined foliar application of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at pre-flowering (S1) and pod formation (S2) stages was most effective in enhancing grain and straw yield, Zn and Fe concentration, and uptake. However, the outcome of this treatment was statistically on par with the results obtained under the treatment ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage. A single spray of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage enhanced the grain and straw yield up to 39.6% and 51.8%, respectively. Similarly, Zn and Fe concentrations showed enhancement in grain (10.9% and 20.4%, respectively) and straw (27.5% and 27.6% respectively) of the lentil. The increase in Zn and Fe uptake by grain was 54.8% and 68.0%, respectively, whereas uptake by straw was 93.6% and 93.7%, respectively. Also the benefit:cost was the highest (1.96) with application of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage. Conclusively, the combined use of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage can contribute significantly towards yield, Zn and Fe concentration, as well as uptake and the economic returns of lentil to remediate the Zn and Fe deficiency.  相似文献   
73.
We explored some unique defects in a batch of cadmium zinc telluride (CdZnTe) crystals, along with dislocations and Te-rich decorated features, revealed by chemical etching. We extensively investigated these distinctive imperfections in the crystals to identify their origin, dimensions, and distribution in the bulk material. We estimated that these features ranged from 50 to 500 μm in diameter, and their depth was about ∼300 μm. The density of these features ranged between 2×102 and 1×103 per cm3. We elaborated a model of them and projected their effect on charge collection and spectral response. In addition, we fabricated detectors with these defective crystals and acquired fine details of charge-transport phenomena over the detectors’ volume using a high-spatial resolution (25 μm) X-ray response mapping technique. We related the results to better understand the defects and their influence on the charge-transport properties of the devices. The role of the defects was identified by correlating their signatures with the findings from our theoretical model and our experimental data.  相似文献   
74.
Vibrationally-resolved photoelectron spectra of AlMoO(y)(-) (y = 1-4) are presented and analyzed in conjunction with density functional theory computational results. The structures determined for the AlMoO(y) anion and neutral clusters suggest ionic bonding between Al(+) and a MoO(y)(-) or MoO(y)(-2) moiety, and point to the relative stability of Mo=O versus Al=O bonds. The highest occupied and partially occupied orbitals in the anions and neutrals can be described as Mo atomic-like orbitals, so while the Mo is in a higher oxidation state than Al, the most energetically accessible electrons are localized on the molybdenum center.  相似文献   
75.
In recent years, indole derivatives have acquired conspicuous significance due to their wide spectrum of biological activities—antibacterial, antiviral, and anticonvulsant. This compound is derived from naturally grown plants. Therefore, synthesis of a novel “3-(Naphthalen-1-ylimino)indolin-2-one” compound (2) and its analysis using UPLC systems along with antimicrobial assessment was the aim of the current study. Isatin was used as a parent drug for synthesizing compound (2). Liquid Chromatographic analysis was performed using a C18 BEH column (1.7 μm 2.1 × 50 mm) by UPLC systems. Degradation studies were carried out to see whether acid, base, thermal, and oxidizing agents had any impact on the synthesized molecule in stress conditions (100 °C). A lipid-based self-nanoemulsifying formulation was developed and selectivity, specificity, recovery, accuracy, and precision were measured as part of the UPLC system’s validation process. Antimicrobial studies were conducted using gram-positive and gram-negative bacteria. The standard samples were run with a concentration range of 5.0–100.0 μg/mL using the isocratic mobile phase comprising of methanol/water (70/30 %v/v) at 234 nm; good linearity (R2 = 0.9998) was found. The lower limits of detection (LOD) and quantitation (LOQ) of the method were found to be 0.81 μg/mL and 2.5 μg/mL, respectively. The coefficients of variation were found to be less than 2%. The antimicrobial study suggests that compound (2) has a substantial growth effect against gram-negative bacteria. It was successfully synthesized and applied to measure the concentrations in lipid-based dosage form, along with potent antimicrobial activities.  相似文献   
76.
The mechanism of interaction between a model antimicrobial peptide and phospholipid unilamellar vesicle membranes was studied using fluorescence spectroscopy, fluorescence lifetime measurements, and light scattering. The peptide, a mellitin mutant, was labeled at position K14 with the polarity-sensitive probe AlexaFluor 430. The kinetics of the interaction of this derivative with various concentrations of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) vesicles was examined. Our work unveiled two novel aspects of peptide-lipid interactions. First, the AB plot or phasor analysis of the fluorescence lifetime studies revealed at least three different peptide states, the population of which depended on the lipid to peptide (L:P) concentration ratio. Second, complex fluorescence kinetics were observed over extended time-scales from 30 s to 2 h. The extended kinetics was only observed at particular lipid concentrations (L:P ratios 20:1 and 10:1) and not at others (30, 40, 50 and 100:1 L:P ratio). Analysis of the complex kinetics revealed several intermediates. We assign these to distinct states of the peptide formed during helix insertion into the vesicle membrane that are intermediate to lytic pore formation.  相似文献   
77.
An efficient and mild method for catalytic transfer hydrogenation of CC and CN double bonds with the aid of resin-supported formate (PSF) as the hydrogen donor and palladium acetate as the catalyst is reported.  相似文献   
78.
A new end-off type acyclic ligand with four hydroxyethyl arms, 2,6-bis[bis(2-hydroxyethyl)aminomethyl]-4-methylphenol [H(bhmp)], formed dinuclear cobalt(II) complexes [Co(2)(bhmp)(OAc)(2)]BPh(4) (1) and [Co(2)(bhmp)(OBz)(2)]BPh(4) (2). The complex 1.2.5CH(3)CN (C(50)H(62.5)BCo(2)N(4.5)O(9)) crystallizes in the monoclinic space group C2/c with dimensions a = 25.424(5) A, b = 13.376(2) A, c = 29.913(6) A, beta = 105.930(3) degrees, and V = 9781(3) A(3) and with Z = 8. X-ray diffraction analysis revealed a mu-phenoxo-bis(mu-acetato)dicobalt(II) core structure containing two octahedral cobalt(II) ions. Electronic spectra were investigated for 1 and 2 in the range 400-1800 nm, and the data were typical for the octahedral high-spin cobalt(II) complexes. Magnetic susceptibility was measured for 1 and 2 over the temperature range 4.5-300 K, and the data were analyzed well using our theoretical method. The best fitting parameters were kappa = 0.77, lambda = -116 cm(-1), Delta = 572 cm(-1), and J = -0.44 cm(-1) for complex 1 and kappa = 0.96, lambda = -93 cm(-1), Delta = 616 cm(-1), and J = -0.33 cm(-1) for complex 2.  相似文献   
79.
80.
The complexation of three isoquinoline alkaloids berberine, palmatine and coralyne with α-, β-, and γ-CDs were studied by absorption, fluorescence, circular dichroism, NMR spectroscopy and microcalorimetric assay techniques. Their binding constant (K BH) values were determined by Benesi–Hildebrand equation. All the alkaloids formed 1:1 stoichiometry complexes with the cyclodextrins (CDs). The binding affinity is largest in β-CD followed by γ-, and α-CD for coralyne, followed by berberine and then palmatine. The thermodynamic parameters of the complexation were determined by calorimetry. The stoichiometry of complex formation and the variation of the apparent binding constant from spectroscopic studies were confirmed by calorimetry. The formation of the inclusion complexes was entropy driven in almost all the systems. Coralyne formed the strongest complex with all the CDs, followed by berberine and palmatine in that order. Coralyne-β-CD complex was studied through NMR, indicating more than one interaction mode.  相似文献   
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