Heterologous expression of a plastid EF-Tu reduces protein thermal aggregation and enhances CO\u3csub\u3e2\u3c/sub\u3e fixation in wheat (\u3ci\u3eTriticum aestivum\u3c/i\u3e) following heat stress

Heat stress is a major constraint to wheat production and negatively impacts grain quality, causing tremendous economic losses, and may become a more troublesome factor due to global warming. At the cellular level, heat stress causes denaturation and aggregation of proteins and injury to membranes leading to alterations in metabolic fluxes. Protein aggregation is irreversible, and protection of proteins from thermal aggregation is a strategy a cell uses to tolerate heat stress. Here we report on the development of transgenic wheat (Triticum aestivum) events, expressing a maize gene coding for plastidal protein synthesis elongation factor (EF-Tu), which, compared to non-transgenic plants, display reduced thermal aggregation of leaf proteins, reduced heat injury to photosynthetic membranes (thylakoids), and enhanced rate of CO2 fixation after exposure to heat stress. The results support the concept that EF-Tu ameliorates negative effects of heat stress by acting as a molecular chaperone. This is the first demonstration of the introduction of a plastidal EF-Tu in plants that leads to protection against heat injury and enhanced photosynthesis after heat stress. This is also the first demonstration that a gene other than HSP gene can be used for improvement of heat tolerance and that the improvement is possible in a species that has a complex genome, hexaploid wheat. The results strongly suggest that heat tolerance of wheat, and possibly other crop plants, can be improved by modulating expression of plastidal EF-Tu and/or by selection of genotypes with increased endogenous levels of this protein

Molar-mass distribution of urea-formaldehyde resins of different degrees of polymerisation by MALDI-TOF mass spectrometry

This paper describes some results obtained in an investigation of urea-formaldehyde (UF) resins of different degrees of polymerisation by matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) mass spectrometry (MS). MALDI-TOF MS proved to be an appropriate technique for analyzing these types of polymers, bearing in mind that the results of the analysis correspond with previous physical and chemical measurements. This technique enables a relatively swift determination of the degree of polymerrisation through the monitoring of key changes in the structure of a polymer. Thus, in the analysis of UF resins, it may be possible to monitor a decrease in the intensity of the monohydroxymethyl urea (MMU) signal, which corresponds to an increase of the mass spectra values in the mass range of higher homologues, above 1000 g mol(-1). A noticeable difference concerns the signal intensities in the higher mass ranges (up to 1400 g mol(-1)), which corresponds to more branched and longer homologues of the polymers. Especially, a significantly more intensive signal of MMU was registered. The average molecular weight (MW) of the examined samples was between 936 and 1324 g mol(-1), with a maximal deviation of 20 %, depending on the ratios of the reactants

TRACE ELEMENTS CONCENTRATIONS ASSOCIATION WITH SCHIZOPHRENIA SYMPTOMS; A CROSS-SECTIONAL STUDY IN CROATIA

Background: Significant inconsistencies exist in findings on association of bio-elements (BE) concentrations and schizophrenia. Hypothesis of this research was that different concentrations of BE are associated with different psychopathological schizophrenia symptoms. Subjects and methods: This cross-sectional study was performed from 2014 to 2016 at Psychiatric Hospital “Sveti Ivan” and University Psychiatric Hospital “Vra

Comparative analyses of water soaking and thickness swelling of particleboard versus different test methods

In regard to its hygroscopic properties, particleboard is dimensionally unstable material when exposed to water or in the atmosphere of high level of humidity. Since today several different standardized methods for determination of thickness swelling exist, the aim of this study was focused on comparison of different testing methods. In this aim, three different methods for determination of water soaking and thickness swelling were compared, two of which were defined by national standard SRPS D.C8.104 and one was defined by European standard EN 317. The results of testing of both properties have shown no significant difference between the EN method based on 50×50 mm test pieces and the SRPS method based on test pieces of 100×100 mm format, suggesting that these two methods can be used alternatively. On the other hand, the results obtained by the SRPS method utilizing the 25×25 mm test pieces, differed significantly from both previous methods. The results were lower for both water soaking and thickness swelling regardless of panel thickness

Study on impact properties of creep-resistant steel thermally simulated heat affected zone

The steam pipe line and steam line material, along with its welded joints, subject to damage that accumulates during operation in coal power plants. As a result of thermal fatigue, dilatation of steam pipe line at an operating temperature may lead to cracks initiation at the critical zones within heat affected zone of steam pipe line welded joints. By registration of thermal cycle during welding and subsequent heat affected zone simulation is possible to obtain target microstructure. For the simulation is chosen heat resisting steel, 12H1MF (designation 13CrMo44 according to DIN standard). From the viewpoint of mechanical properties, special attention is on impact toughness mostly because very small number of available references. After simulation of single run and multi run welding test on instrumented Charpy pendulum. Metallographic and fractographic analysis is also performed, on simulated 12H1MF steel from service and new, unused steel. The results and correlation between microstructure and impact toughness is discussed, too

Determining the degree of fireretardancy of plywood with thermogravimetry, part II: Poplar plywood

In the aim to achieve fire-resistant plywood of different wood species, in this study, veneers have been impregnated with solutions of chosen fire retardants, which are diammonium phosphate, monoammonium phosphate, sodium acetate, water glass, sodium tetraborate and boric acid. To determine the preliminary level of fire retardancy achieved in veneers before manufacturing of finished plywood, thermogravimetric (TG) and derivative thermogravimetric (DTG) methods are used. TG and DTG analyses of treated and untreated wood, as well as of fire retardants alone, were performed on a Perkin-Elmer TGS-2 thermogravimetric equipment. Fire resistance of plywood was tested in accordance with standard test for resistance to the effects of fire and the most efficient fire retardants, sodium tetraborate and boric acid had the same results as TG/DTG analyses, which points out the validity of TG methods in predicting success of fire retardants in future products

Phenotypic and genetic heterogeneity of adult patients with hereditary spastic paraplegia from Serbia

Hereditary spastic paraplegia (HSP) is among the most genetically diverse of all monogenic diseases. The aim was to analyze the genetic causes of HSP among adult Serbian patients. The study comprised 74 patients from 65 families clinically diagnosed with HSP during a nine-year prospective period. A panel of thirteen genes was analyzed: L1CAM (SPG1), PLP1 (SPG2), ATL1 (SPG3A), SPAST (SPG4), CYP7B1 (SPG5A), SPG7 (SPG7), KIF5A (SPG10), SPG11 (SPG11), ZYFVE26 (SPG15), REEP1 (SPG31), ATP13A2 (SPG78), DYNC1H1, and BICD2 using a next generation sequencing-based technique. A copy number variation (CNV) test for SPAST, SPG7, and SPG11 was also performed. Twenty-three patients from 19 families (29.2%) had conclusive genetic findings, including 75.0% of families with autosomal dominant and 25.0% with autosomal recessive inheritance, and 15.7% of sporadic cases. Twelve families had mutations in the SPAST gene, usually with a pure HSP phenotype. Three sporadic patients had conclusive findings in the SPG11 gene. Two unrelated patients carried a homozygous pathogenic mutation c.233T>A (p.L78*) in SPG7 that is a founder Roma mutation. One patient had a heterozygous de novo variant in the KIF5A gene, and one had a compound heterozygous mutation in the ZYFVE26 gene. The combined genetic yield of our gene panel and CNV analysis for HSP was around 30%. Our findings broaden the knowledge on the genetic epidemiology of HSP, with implications for molecular diagnostics in this region