Academic literature on the topic 'Neurosciences, biological and chemical aspects, n.e.c'

Problems with weed infestation under cover were the reason to conduct research on the regulation of weed infestation in potato cultivation for early harvest. The field experiment was carried out in 2015–2017 at the Experimental Station for Cultivar Assessment in Uhnin (51°34′ N, 23°02′ E) using the method of random subblocks, in a dependent system (split-split-plot). The first order factor was edible potato cultivars ‘Denar’ and ‘Lord’. The second order factor was cultivation technologies: (A) traditional technology, (B) technology using polyethylene film cover, (C) technology using polypropylene agrotextile. The third order factor was weed management methods: (1) mechanical, (2) mechanical and chemical method using Afalon Dispersion 450 SC preparation, (3) mechanical and chemical methods using Racer 250 EC herbicide, and (4) mechanical and chemical methods using a mixture of herbicides Afalon Dispersion 450 SC and Command 480 EC. Mechanical and chemical methods proved to be more effective than the mechanical method. The best effectiveness in limiting both fresh and dry weed mass in potato cultivation under cover was achieved using the mechanical and chemical method using a mixture of herbicides, Afalon Dispersion 450 SC and Command 480 EC.

Determining biological parameters such as length to weight relationship, sex ratio and size at first maturity of threatened fishes give good information on their growth performance and help manage and conserve fish populations in their natural water bodies. In this study, some biological parameters were reported for Clarias gariepinus and Cyprinus carpio. Samples were taken at monthly intervals from October 2013 to September 2017 in Lake Lugo, South Wollo, Ethiopia. The objective of the study was to determine length to weight relationships, length class frequency, sex ratio and size at first maturity of the fishes. Total length (TL) of the species was measured to the nearest 0.1 cm and total body weight (TW) to the nearest 1 g. The physico-chemical parameters were also measured: transparency by using secchi disk, conductivity by Wagtach International conductivity meter and pH by pH meter. The results showed that the parameters were within the permissible limits except the pH level at Gedam Sefar sampling site. A total of 672 fish specimens were collected. Length (cm) to weight (g) relationship for C. gariepinus was sketched as: TW = 0.015TL2.8, n = 81, r2 = 0.901 and for C. carpio as: TW = 0.018TL2.85, n = 591, r2 = 0.926, which, in both cases, showed a curvilinear relationship, signifying the fishes followed negative allometric growth. The sex ratio between males to females showed significant difference (C. gariepinus: χ2 = 4.46, P<0.05; C. carpio: χ2 = 12.0, P<0.05). Size at first sexual maturity (L50) for C. gariepinus was 31.7 cm for females and 31.1 cm for males, while L50 for C. carpio was 19.2 cm for females and 19.3 cm for males.

The descriptive explored study was conducted in districts Bumi Nabung, Sari Bakti, Seputih Banyak and Rumbia, Central Lampung, Indonesia. The parameters observed consisted of chemical and biological aspects of soil, which directly affected plant growth. This activity was carried out as preliminary studies for the diagnosis of soybean extensification on acid dry land. The results showed that all locations observed were less suitable for soybean development, indicated by low pH values (4.35 – 6.00), nutrient contents (N < 0.1% and C-organic < 2.0%), and low soil microbial populations. Population of bacteria was 17 × 103 – 29 × 104 CFU g-1 soil and fungi was 21 × 101 – 63 ×102 CFU g-1 soil of soils. Beneficial microbe types included non-symbiotic nitrogen-fixing bacteria (with the capability to fix the Nitrogen around 0.16 – 1.53 mM 100 ml-1 medium h-1), phosphate solubilizing bacteria (with the value index 1.22 – 6.25) and arbuscular mycorrhizal fungi (with root colonization by 70.50 – 90.33% and the number of sporeswere 49 – 175 spores g-1 soil). This less suitable land can be improved to become suitable for developing soybean by using innovative technology. Soil biological and chemical improvement technology through liming and amelioration as well as organic and bio-fertilizers applications were required for soybeans extensification on acid dry land.[How to Cite: Prihastuti and Sudaryono. 2013. Soil Chemical and Biological Characteristics for Diagnostic the Potency of Acid Dry Land for Soybean Extensification. J Trop Soils, 18 (1) : 17-24. doi: 10.5400/jts.2013.18.1.17][Permalink/DOI: www.dx.doi.org/10.5400/jts.2013.18.1.17]

Abstract“Biomimetic” and “bioinspired” define different aspects of the impacts that biology exerts on science and engineering. Biomimicking improves the understanding of how living systems work, and builds tools for bioinspired endeavors. Biological inspiration takes ideas from biology and implements them in unorthodox manners, exceeding what nature offers. Molecular electrets, i.e. systems with ordered electric dipoles, are key for advancing charge-transfer (CT) science and engineering. Protein helices and their biomimetic analogues, based on synthetic polypeptides, are the best-known molecular electrets. The inability of native polypeptide backbones to efficiently mediate long-range CT, however, limits their utility. Bioinspired molecular electrets based on anthranilamides can overcome the limitations of their biological and biomimetic counterparts. Polypeptide helices are easy to synthesize using established automated protocols. These protocols, however, fail to produce even short anthranilamide oligomers. For making anthranilamides, the residues are introduced as their nitrobenzoic-acid derivatives, and the oligomers are built from their C- to their N-termini via amide-coupling and nitro-reduction steps. The stringent requirements for these reduction and coupling steps pose non-trivial challenges, such as high selectivity, quantitative yields, and fast completion under mild conditions. Addressing these challenges will provide access to bioinspired molecular electrets essential for organic electronics and energy conversion.

The purpose of this research is to know the characteristic 'water quality' river ancar Mataram city based on biological, chemical, and physics as bioremidiasi waters. The type of this research is descriptive explorative and research method used is survey, laboratory analysis, and case study, ie method of all aspects must be observed fully, while the data analysis is only valid for certain place and time period. The results showed that, overall observation and identification of 6 research sampling stations, 21 species were identified with four microlagae classes: Bacillariophyceae, Cyanopyceae, Chlorophyceae and Crysophyceae. Bacillariophyceae class is the class that has the most types, then Cyanophyceae, Chlorophyceae and Chrisophyceae. Factors supporting the growth of bologic components such as pH, temperature, light intensity, salinity with the range of each 7.2-8.3; 25-27 ° C; 1011-1800 lux; 3-3.2%, nutrients (N and P), according to the microalgae living conditions which are the most primitive plant organisms that are small in size, live in all waters, both rivers and seawater.

The biocompatibility of pNiPAM (Poly N-isopropylacrylamide) copolymers has been examined and they did not exert any cytotoxic effects. Their properties and vulnerable temperature characteristics make them candidates for use in medical applications. We synthesized a well-characterized nanoparticles-based cargo system that would effectively deliver a biological agent to human skeletal myogenic cells (SkMCs); among other aspects, a downregulating apoptotic pathway potentially responsible for poor regeneration of myocardium. We confirmed the size of the pNiPAM based spheres at around 100 nm and the nanomeric shape of nanoparticles (NP) obtained. We confirmed that 33 °C is the adequate temperature for phase transition. We performed the dynamics of cargo release. A small amount of examined protein was detected at 10 min after reaching LCTS (lower critical solution temperature). The presented results of the test with BSA (bovine serum albumin) and doxorubicin loaded into nanoparticles showed a similar release profile for both substances. SkMCs incubated with NP loaded with antiapoptotic agent, BCB (Bax channel blocker), significantly diminished cell apoptosis (p < 0.01). Moreover, the lowest apoptotic level was detected in SkMCs treated with camptothecin and simultaneously incubated with pNiPAMs loaded with BCB. Application of nanoparticles loaded with BCB or subjected to BCB alone did not, however, diminish the amount of apparently necrotic cells.

In spite of the achievements in the chemistry of triazoloquinazolines, the synthetic possibilities of this class of compounds are not exhausted, some problems remain unresolved and require further study. 2-R-[1,2,4]triazolo[1,5-с]quinazolines are among them due to insufficiently explored but at the same time interesting in both chemical and biological aspects. Undoubtedly «pharmacophore» has the crucial role in the response of a biological action. It is contained in this heterocycle namely the substitute position 2. In view of the above, we attempted to modify triazolo[1,5-с]quinazoline by introducing a methyl group or halogens (fluorine, chlorine, bromine) into a benzene moiety and a triazole moiety of a cycloalkyl or heterocyclic substituent molecule. The aim of this work is to develop simple and affordable methods of the synthesis of new 2-cycloalkyl-(hetaryl-)-[1,2,4]triazolo[1,5-с]quinazolines, quinazolines, to study their physical and chemical properties and to conduct primary screening for antibacterial activity The antimicrobial activity of the synthesized chemical compounds was performed by the method of two-fold serial dilutions in Mueller–Hinton broth (for strains of Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) and in Saburo broth (for Candida albicans ATCC 885–653). MIC (minimum inhibitory concentration), MBсC and MFсC (minimum bactericidal and fungicidal concentrations respectively) was determined. The optimal method of synthesis of 2-cycloalkyl-(hetaryl-)-[1,2,4]triazolo[1,5-с]quinazolines, which represent value as chemical reagents for further transformations and study of biological activity is substantiated and developed. The possibility of «one-pot» synthesis of the target compounds with 4-hydrazinoquinazolines and cycloalkylcarboxylic acids under conditions of activation of the carboxyl group N,N¢-carbonyldiimidazole is shown. Conducted microbiological screening of 2-cycloalkyl-(hetaryl-)-[1,2,4]triazolo[1,5-с]quinazolines revealed a number of promising compounds that inhibit the growth of St. aureus (МІС 25‒50 μg/ml) and C. albicans (25‒50 μg/ml). The optimal method of synthesis of 2-cycloalkyl-(hetaryl-)-[1,2,4]triazolo[1,5-с]quinazolin by cyclocondensation (3Н-quinazoline-4-ylidene)­hydrazides withcycloalkyl-(hetaryl)carboxylic acidsis substantiated and developed. The structure and individuality of the synthesized compounds were confirmed by elemental analysis, physicochemical methods (1H NMR-spectroscopy, HPLC/MS). The peculiarity of the 1H NMR spectra of this heterocycle is discussed, namely the significant paramagnetic shift of benzene protons and the characteristic weak-field single-proton singlet of the proton of position 5 of the heterocycle, which is a confirmation of recycling isomerization by Dimrot rearrangement. The structure-activity relationship is discussed and the study of the most active compounds for a wider range of strains and resistant strains of bacteria and fungi is recommended.

In the last few decades, the studies in second language acquisition have not answered the question what mechanisms a human’s brain uses to make acquisition of language(s) possible. A neurocognitive model which tries to address SLA from such a perspective was suggested by Ullman (2005; 2015), according to which, “both first and second languages are acquired and processed by well-studied brain systems that are known to subserve particular nonlanguage functions” (Ullman, 2005: 141). The brain systems in question have analogous roles in their language and nonlanguage functions. This article is meant to critically analyse the suggested DP model within the context of neurocognitive studies of L2; and evaluate its contribution to the field of SLA studies. References Aboitiz, F. (1995). Working memory networks and the origin of language areas in the human brain. Medical Hypothesis, 25, 504-506. Aboitiz, F. & Garcia, R. (1977). The anatomy of language revisited. 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<p>Abstrak. Penggenangan terus-menerus di lahan sawah akan berpengaruh terhadap keseimbangan kimia dan biologi tanah. Pergantian aerobik dan anaerobik di lahan sawah merupakan satu kontrol alami yang efektif mengendalikan keseimbangan biologi dan nonbiologi sehingga tanah sawah menjadi sehat dan tetap produktif. Penerapan rotasi tanamanantara tanaman padi dengan palawija maupun hortiklutura merupakan salah alternatif yang bijak untuk tetap mempertahankan produktivitas dan kesuburan lahan, dan perekonomian petani. Penerapan rotasi tanam memiliki peranan terhadap beberapa aspek antara lain agronomi, ekonomi dan lingkungan. Pengelolaan lahan pertanian tanah sawah secara terus-menerus pada berbagai rotasi tanam dapat meningkatkan berat jenis tanah, dan persentase fraksi lempung dalam tanah sawah. Rotasi tanaman padi-palawija/hortikultura dapat memperbaiki srtuktur tanah melalui peningkatan nilai MWD. Penerapan rotasi tanaman secara terus-menerus berpengaruh nyata terhadap perubahan sifat kimia tanah seperti pH, N-total, P dan K-tersedia, KPK tanah, dan C-organik. Penerapan rotasi tanaman padi-jagung pada 1 – 2 tahun pertama memberikan kadar N-total tanah, NO₃^- dan DOC yang sangat tinggi. Penanaman jagung di musim kemarau pada rotasi tanaman padi-jagung dapat menyimpan air dan menekan pencucian hara, daripada penanaman padi-padi dalam jangka panjang. Pengembalian nutrisi nitrogen dalam rotasi tanaman dapat dilakukan melalui penanaman tanaman legum setelah penanaman tumbuhan serealia dan sejenisnya.</p><p>Abstract. Continuous flooding in paddy fields will disrupt the biological and chemical balance of the soil. Substitution of aerobics and anaerobics in paddy fields is a natural control that effectively controls the biological and nonbiological balance so that the paddy fields become healthy and remain productive. Application of plant rotation between rice plants with crops and horticulture is a wise alternative to maintain the productivity and fertility of paddy field, and the economy of farmer. Application of rotation has a role to play on several aspects such as agronomy, economy and environment. Continuous management of paddy field on various rotations of cropping can increase bulk density, and the percentage of clay fraction in paddy soil. Rotation of rice-upland/horticulture can improve soil structure by increasing the value of MWD. Continuous application of crop rotation has a significant effect on changes in soil chemical properties such as pH, totalN, available P and K, CEC, and organic carbon. The application of rotation of rice-maize in the 1–2 years can give very high total N, NO₃^- and DOC levels. The planting of maize in the dry season on a rotation of rice-maize can store water and suppress nutrient leaching, rather than long-term rice-rice cultivation. Return of nitrogen nutrients in crop rotation can be done through planting legumes after planting cereals and the like.</p>

Glutathione (γ-L-glutamyl-L-cysteinyl-glycine, γ-Glu-Cys-Gly) is the most abundant intra-cellular dicarboxylic tripeptide with multiple physiological roles. In biological samples, glutathione exists in its reduced form GSH and in two stable oxidized forms, i.e., in its symmetric disulfide form GSSG and as S-glutathionyl residue in proteins. S-Glutathionylation is a post-translational modification, which is involved in several pathophysiological processes, including oxidative stress. The GSH-to-GSSG molar ratio is widely used as a measure of oxidative stress. γ-Glutamyl is the most characteristic structural moiety of GSH. We performed gas chromatography-mass spectrometry (GC-MS) studies for the development of a highly specific qualitative and quantitative method for γ-glutamyl peptides. We discovered intra-molecular conversion of GSH, GSSG, γ-Glu-Cys and of ophthalmic acid (OPH; γ-glutamyl-α-amino-n-butyryl-glycine) to pyroglutamate (pGlu; 5-oxo-proline, also known as pidolic acid) during their derivatization with 2 M HCl/CH3OH (60 min, 80 °C). For GC-MS analysis, the methyl esters (Me) were further derivatized with pentafluoropropionic (PFP) anhydride in ethyl acetate (1:4, v/v; 30 min, 65 °C) to their PFP derivatives. At longer reaction times, pGlu is hydrolyzed to Glu. Internal standards were prepared by derivatizing GSH, GSSG, γ-Glu-Cys and OPH in 2 M HCl/CD3OD. Quantification of the Me-PFP derivative of pGlu was performed in the electron-capture negative-ion chemical ionization (ECNICI) mode by selected-ion monitoring (SIM) of the mass-to-charge (m/z) ions 269 for unlabeled pGlu (d0Me-PFP-pGlu) and m/z 272 for the in situ prepared deuterium-labeled pGlu (d3Me-PFP-pGlu). Although not inherent to the analysis of small peptides, the present GC-MS method is useful to study several biochemical aspects of GSH. Using pentafluorobenzyl bromide (PFB-Br) as the derivatization reagent, we found that synthetic pGlu is converted in aqueous acetone (60 min, 50 °C) into its pentafluorobenzyl (PFB) ester (PFB-pGlu). This derivatization procedure is useful for the GC-MS analysis of free pGlu in the ECNICI mode. Quantitative analysis of PFB-pGlu by GC-MS requires the use of stable-isotope labeled analogs of pGlu as an internal standard.