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Purpose: To determine the clinical significance of choroidal thickness and evaluate changes in choroidal thickness over time in eyes affected by ocular ischemic syndrome (OIS).Methods: Medical records of 16 patients diagnosed with OIS between November 2017 and August 2019 were retrospectively reviewed. In every nine areas of the Early Treatment Diabetic Retinopathy Study grid, we compared the differences in choroidal thickness between the eyes with OIS and unaffected eyes, and its change in the OIS eyes during the follow-up period using swept-source optical coherence tomography. We analyzed the best-corrected visual acuity, intraocular pressure, fluorescein angiography (FAG) parameters, systemic diseases, and the duration of symptoms. Correlation between FAG parameters and the choroidal thickness value ratio in the OIS eyes and the unaffected eyes, and changes in the choroidal thickness in the OIS eyes during follow-up were investigated.Results: Median age of the subjects was 67.5 years. In the OIS eyes, all FAG parameters were delayed at the initial examination. Best-corrected visual acuity and intraocular pressure were significantly different between the OIS and unaffected eyes. While the choroidal thickness in every nine areas of Early Treatment Diabetic Retinopathy Study in the OIS eyes was lesser than the unaffected eyes, the choroidal thickness of inner temporal, outer nasal, and outer temporal area showed statistically significant difference. During follow-up, changes in choroidal thickness of OIS eyes as well as correlation between the FAG parameters and the choroidal thickness value ratio between the OIS eyes and the unaffected eyes were not found to be statistically significant.Conclusions: The choroidal thickness of the eyes with OIS was significantly less compared with the unaffected eyes. We inferred that choroidal thinning takes place in the early phase of the disease as the changes in choroidal thickness during the follow-up period were not significant.

Accumulated evidence suggests that peptides play diverse roles in various aspects of plant growth and development. Therefore, many research groups have developed and utilized new methods for the identification of peptides in different organisms. Nevertheless, the number and diversity of identified peptides remain lower than expected. In addition, the number of identified peptides is underestimated because of their low endogenous concentrations and, consequently, technical difficulties with their isolation. Additionally, while some types of peptides undergo functional maturation via proteolytic processing or post-translational modifications, which are important for their biological activity, most of the enzymes involved in the maturation of peptides have not yet been identified. Together, these factors indicate that the investigation of peptides is in its beginning stages in plants, as in other organisms. This review summarizes the biosynthesis mechanisms, identification tools, post-translational modifications, and biological functions of plant peptides, and the importance of post-translational modifications in peptide activity.

Arabidopsis PATATIN-RELATED PHOSPHOLIPASE 2A (pPLA-IIα) participates in the responses to various growth conditions. The factors affecting pPLA-IIα gene expression and pPLA-IIα protein activity for gycerolipids have been studied thoroughly, but the role of pPLA-IIα during the reproductive phase remains unclear. The effect of pPLA-IIα on flowering time was therefore investigated. ppla-iiα mutants flowered later than wild-type plants under long day conditions. Expression of the floral stimulators FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) was downregulated in ppla-iiα mutants compared with their expression in wild-type plants, but expression of the floral repressor FLOWERING LOCUS C (FLC) was upregulated. In addition, expression levels of COLDAIR, a long intronic noncoding RNA, decreased in ppla-iiα mutants. Taken together, these data indicate that pPLA-IIα acts as a positive regulator of flowering time through repression of FLC expression.

Small peptides and proteins play critical regulatory roles in plant development and environmental stress responses, however, only a few of these molecules have been identified and characterized to date because of their poor annotation and other experimental challenges. Here, we present that rice (Oryza sativa L.) OsS1Fa1, a small 76-amino acid protein, confers drought stress tolerance in Arabidopsis thaliana. OsS1Fa1 was highly expressed in leaf, culm, and root tissues of rice seedlings during vegetative growth and was significantly induced under drought stress. OsS1Fa1 overexpression in Arabidopsis induced the expression of selected drought-responsive genes and enhanced the survival rate of transgenic lines under drought. The proteasome inhibitor MG132 protected the OsS1Fa1 protein from degradation. Together, our data indicate that the small protein OsS1Fa1 is induced by drought and is post-translationally regulated, and the ectopic expression of OsS1Fa1 protects plants from drought stress.

Aim To determine vitamin D deficiency risk and other lifestyle factors in children aged 2–17 years presenting with an acute fracture to Sunshine Hospital. Methods A prospective observational study was undertaken using a convenience sample data collected from children aged 2–17 years of age presenting with an acute fracture. Recruitment was undertaken over a 3-month period from February to May 2014. Risk factors for vitamin D deficiency (skin pigmentation, hours spent outdoors, sunscreen use and obesity) were identified. Patients providing consent, had measurements of serum 25-hydroxyvitamin D (25-OHD). Vitamin D deficiency was defined as, Highlights • Prevalence of vitamin D deficiency is high in multiethnic children, presenting with fracture with risk factor(s) of vitamin D deficiency. • Reduced sun exposure or hyperpigmentation have a strong association with vitamin D deficiency. • Screening for vitamin D deficiency and assessment of dietary calcium adequacy are recommended when a child or teenager presents with an acute fracture.

In this paper, a bidirectional power supply charger is proposed. This system used a solar cell panel to generate electricity and used super capacitors to store these energies, which can be used for the robot cleaner or some other electronic products. This system include a phase-shift controlled bidirectional dual active bridge (DAB) converter, solar panel super capacitors and DSP controller. In the daytime it can charge to the super capacitors to store the energy generated by the solar cell panel and in the night it will release the energy stored in the super capacitors to loads. A prototype of the proposed bidirectional power supply charger system was designed which can achieve 18V to 30V input, 10V/20W output to super capacitors and 9V/6.5W output when it acts as a charger for the robot cleaner. The system is verified to be sTable and reliable by both the simulation and experimental results.

This paper describes Battery management Unit with cell balancing for micro-grid solar powered energy storage system. This system include MPPT (increase efficiency of solar cell), BMU (Control battery charge/discharge). Use power semiconductor switch, sense solar cell generate power, load consume power, SOC (State of Charge) Control power flow and battery charge/discharge. BMU also increases total battery capacity and prevent accident.

TiB2-43vol.%Cu nanocomposite powders with titanium diboride particle size 50-100 nm were cold and detonation sprayed in order to fabricate coatings on a copper substrate. The powders were produced by self-propagating high-temperature synthesis (SHS) followed by mechanical milling. The temperatures during spraying were calculated and the change in the nanostructure of the powders during spraying was studied: in cold sprayed coatings the size of TiB2 particles was well retained, in detonation sprayed coatings the growth of the particles was observed, the mode of spraying greatly affecting the microstructure and the size of the particles. The hardness of cold sprayed coatings was higher compared to detonation sprayed coatings. This research shows the future potential for development of coatings with submicron and nanostructure by cold and detonation spraying of powders produced by mechanical milling.

TiB2-Cu composites in a nanostructured state are candidates for high-strength conductive and erosion-resistant materials. In this work, we studied formation of nanostructured TiB2-Cu composites under shock wave conditions. We investigated the influence of preliminary mechanical activation (MA) of Ti-B-Cu powder mixtures on the peculiarities of the reaction between Ti and B under shock wave. In the MA-ed mixture the reaction proceeded completely while in the nonactivated mixture the reagents remained along with the product – titanium diboride. The size of titanium diboride particles in the central part of the compact was 100-300 nm. This research shows that shock wave synthesis in mechanically activated powder mixtures with simultaneous compaction of the composite is a promising way to materials with submicron and nanostructures.

In the present work, Cu-TiB2 nanocomposite powders were synthesized by combining high-energy ball-milling of Cu-Ti-B mixtures and subsequent self-propagating high temperature synthesis (SHS). Cu-40wt.%TiB2 powders were produced by SHS reaction and ball-milled. The milled SHS powder was mixed with Cu powders by ball milling to produce Cu-2.5wt.%TiB2 composites. TiB2 particles less than 250nm were formed in the copper matrix after SHS-reaction. The releative density, electrical conductivity and hardness of specimens sintered at 650-750°C were nearly 98%, 83%IACS and 71HRB, respectively. After heat treatment at 850 to 950°C for 2 hours under Ar atmosphere, hardness was descedned by 15%. Our Cu-TiB2 composite showed good thermal stability at eleveated temperature.

Dispersion-strengthened copper with TiB2 was produced by ball-milling and spark plasma sintering (SPS).Ball-milling was performed at a rotation speed of 300rpm for 30 and 60min in Ar atmosphere by using a planetary ball mill (AGO-2). Spark-plasma sintering was carried out at 650°C for 5min under vacuum after mechanical alloying. The hardness of the specimens sintered using powder ball milled for 60min at 300rpm increased from 16.0 to 61.8 HRB than that of specimen using powder mixed with a turbular mixer, while the electrical conductivity varied from 93.40% to 83.34%IACS. In the case of milled powder, hardness increased as milling time increased, while the electrical conductivity decreased. On the other hand, hardness decreased with increasing sintering temperature, but the electrical conductiviey increased slightly

Ti-Cu-Ni-Sn quaternary amorphous alloys of Ti50Cu32Ni15Sn3, Ti50Cu25Ni20Sn5, and Ti50Cu23Ni20Sn7 composition were prepared by mechanical alloying in a planetary high-energy ballmill (AGO-2). The amorphization of all three alloys was found to set in after milling at 300rpm speed for 2h. A complete amorphization was observed for Ti50Cu32Ni15Sn3 and Ti50Cu25Ni20Sn5 after 30h and 20h of milling, respectively. Differential scanning calorimetry analyses revealed that the thermal stability increased in the order of Ti50Cu32Ni15Sn3, Ti50Cu25Ni20Sn5, and Ti50Cu23Ni20Sn7.

Preparation of titanium diboride reinforced copper matrix composites with high conductivity and mechanical strength was developed based on in situ produced powders. The effect of the titanium diboride content on the mechanical properties of the bulk material produced from the powders by Spark Plasma Sintering technique was studied. Increasing titanium diboride content from 2.5 up to 7.5 wt.% resulted in a 1.5-fold increase in yield strength, tensile strength and hardness and 5-fold increase in wear resistance with only 10% decrease in conductivity.

This work reports on the production of Cu-Hf-Ti bulk glassy composites through a powder metallurgical route, i.e. by mechanical alloying and subsequent spark-plasma sintering. Powders of Cu60Hf30Cu10 and Cu60Hf25Ti15 composition were prepared using a high-energy planetary ball-mill. Both alloys nearly showed a fully amorphous structure with only a small fraction of residual HCP Hf grains left after 50 h of milling. Differential scanning calorimetry (DSC) analyses of the milled glassy powder revealed a two-stage crystallization process for both compositions. However, the released crystallization enthalpy was substantially larger for the Cu60Hf25Ti15 alloy than for the Cu60Hf30Ti10 alloy, suggesting that the former comprises a higher fraction of the amorphous phase than the latter. Both powders showed distinct glass-transition with a large super-cooled liquid region. Consolidation of Cu60Hf25Ti15 powder was carried out by means of spark-plasma sintering at applied pressures of 200 and 500 MPa, choosing a sintering temperature within the super-cooled liquid region (T = 753 K). The sintered compacts exhibited some pores and interparticle boundaries.

The microstructure and properties of Cu-TiB2 composites produced by high-energy ball-milling of TiB2 powders and spark-plasma sintering (SPS) were investigated. TiB2 powders were mechanically milled at a rotation speed of 1000rpm for short time in Ar atmosphere, using a planetary ball mill. To produce Cu-xTiB2 composites( x = 2.5, 5, 7.5 and 10wt.% ), the raw and milled TiB2 powders were mixed with Cu powders by means of a turbular mixer, respectively. Sintering of mixed powders was carried out in a SPS facility under vacuum. High-energy ball-milling resulted in refinement of TiB2 particles. XRD patterns of milled TiB2 powders indicated broader TiB2 peaks with decreased intensities. After sintering at 950 for 5min using the raw and milled TiB2 mixture powders, the sintered density decreased with increasing TiB2 content regardless of milling of TiB2. In the case of raw TiB2, hardness rapidly increased from 4 to 44 HRB with increasing TiB2 content. The electrical conductivity changed from 95.5 to 80.7 %IACS. For mixtures of Cu powders with milled TiB2 powders, hardness increased from 38 to 67 HRB as TiB2 content increased, while the electrical conductivity varied from 88% to 51 % IACS. When compared to compacts sintered with raw and milled TiB2 powders, the electrical conductivity of specimens with raw TiB2 powder was higher than that of specimens with milled TiB2 powder, while hardness was slightly lower.

The particle size effect on the peritectic melting of FeSn2 particles in FeSn-FeSn2 nanocomposites was studied using differential scanning calorimetry and X-ray diffraction. FeSn-10 wt.% FeSn2 compounds, mechanically milled for 30 min and slowly heated in a differential scanning calorimeter, showed incongruent melting at 680 K. Although FeSn2 grains grew from 10 to 40 nm upon heating before peritectic melting set in, the melting temperature was more than 100 K lower than the equilibrium value. A small latent heat during peritectic melting and a large amount of interfacial energy of FeSn-FeSn2 nanocomposites are held responsible for this large particle size effect. Grain growth is hardly possible in the case of rapid local heating during mechanical milling. Therefore, a decrease in the peritectic melting temperature is even expected to be substantially larger.

Nanosize nickel powders were successfully produced by electrical explosion of wire (EEW). In EEW, the nickel wire was discharged in a chamber filled with nitrogen or argon gas, and the produced powders were subsequently stabilized by air-passivation at room temperature for 2 h. X-ray diffraction only showed the nickel phase of FCC crystal structure, whereas TEM and XPS analyses showed the formation of a very thin oxide layer of NiO on the surface of particles. Particles were spherical in shape, and the mean particle size calculated by specific surface area was about 100 nm. The particle size decreased with increasing charging voltage and with increasing ambient gas pressure. Argon gas was more effective in producing finer particles than nitrogen gas.

Al-La-Ni-Fe alloys of three different compositions (Al82La10Ni4Fe4, Al85La9Ni3Fe3 and Al88La6Ni3Fe3) were prepared high-energy milling in a planetary ball-mill (AGO-2). Complete amorphization was observed for the Al82La10Ni4Fe4 alloy after milling for 350 h at a rotational speed of 300 rpm. In contrast, the Al85La9Ni3Fe3 and Al88La6Ni3Fe3 powders contained the FCC Al phase even for prolonged milling. The amorphization tendency was found to increase in the order of Al88La6Ni3Fe3 < Al85La9Ni3Fe3 < Al82La10Ni4Fe4, which may well be ascribed to the increasing atomic size mismatch of the constituent elements on La addition. DSC analyses of amorphous samples revealed two-stage crystallization processes for all three alloys, however, with strong variations in the thermal stability upon compositional changes. As observed by SEM, amorphous powders consisted of particles with nearly spherical shape and diameters ranging from 5 to 20 µm.

Cu-TiB2 nanocomposite powders were in situ synthesized by combining high-energy ball milling of Cu-Ti-B elemental powder mixtures as precursors and subsequent self-propagating high temperature synthesis (SHS). Cu-40wt.% TiB2 was produced after SHS reaction and then diluted by copper to obtain desired homogeneous composites with 2.5, 5 and 10wt.%TiB2. Spark plasma sintering (SPS) was used to inhibit grain growth and thereby obtain fully Cu-TiB2 sintered bodies with nanocomposite structure. After SHS reaction, only Cu and TiB2 phases were detected in the SHS-product. Spheroidal TiB2 particles smaller than 250nm were formed in the copper matrix after SHS-reaction. Mechanical and electrical properties were investigated after SPS at 650°C for 30min under 50MPa. The electrical conductivity decreased from 75 to 54% IACS with increasing of TiB2 contents from 2.5 to 10wt.%. However, hardness increased from 56 to 97HRB. In addition, the tensile strength increased with increasing the TiB2 content.

Ultrafine tantalum carbide (TaC)–5 wt.% Co composite powders were synthesized by a spray-carbothermal process, which includes (i) preparation of precursor powder by spray drying of a liquid solution of tantalum oxalate and cobalt nitrate hexahydrate, (ii) calcination to evaporate volatile components in the precursor powder and synthesis of nanostructured tantalum–cobalt composite oxides and (iii) ball milling with carbon, and subsequent carbothermal reaction in hydrogen. The formation temperature of TaC in this process (1050 °C) is significantly lower than that in the conventional method (1500 °C). The observed particle size of TaC–Co composite powders was smaller than 200 nm.

Ultrafine TaC powders were synthesized by mechano-chemical process (MCP). The synthesis procedures include (1) preparation of precursor powder by spray drying of liquid solution of tantalum oxalate, (2) calcinations to evaporate volatile components in the precursor powder and synthesis of nanostructured tantalum oxides, (3) ball milling with carbon homogeneously, and then carbothermal reaction in hydrogn. The formation temperature (1050 °C) of TaC in this process is significantly lower than that (1500 °C) in the conventional method. The observed size of TaC composite powders by TEM was smaller than 200 nm.

The TaC/VC inhibitor was added in nanophase WC/Co powders by either a mechanicalor chemicaldoping method. The microstructure and mechanical properties have been investigated for the WC/Co hard alloys which were sintered with these powders. After sintering, most of the WCs maintained their original round morphology and fine microstructure. In the mechanically doped alloy, exaggerated and abnormal local grain growth was observed which was supposed to be caused by the non-uniform distribution of the TaC/VC dopant. However, such an abnormal grain growth problem does not appear in the alloy when the inhibitors were chemically doped into the powders. Due to relatively fine and homogeneous microstructure, the nanophase WC/Co doped by the chemicalmethod showed a higher hardness and better transverse rupture strength than that doped by the mechanicalmethod.

Nanocomposite Cu-TiB/sub 2/ powder was in situ synthesized by means of self-propagating high-temperature synthesis (SHS) using high-energy ball milled Ti-B-Cu elemental mixtures as powder precursors. The effect of the preliminary mechanical treatment on the SHS reaction was studied. The size of TiB/sub 2/ particles produced by SHS was shown to decrease with increasing duration of the preliminary mechanical treatment. Subsequent mechanical treatment of the SHS products led to a reduction of TiB/sub 2/ particle sizes down to 30-50 nm. The microstructural evolution of the synthesized powder compacts during sintering was investigated. During spark plasma sintering a fine-grained skeleton of TiB/sub 2/ with well connected particles is formed. This interpenetrating phase composite of Cu-TiB/sub 2/ is produced by the simultaneous action of pressure, temperature and electrical current. TiB/sub 2/ nanoparticles distributed in the copper matrix agglomerate and form a fine-grained skeleton.

Cu-TiB/sub 2/ was fabricated by combination of mechanical treatment, SHS (self propagating high temperature synthesis) and SPS (spark plasma sintering). The feasibility of Cu-TiB/sub 2/ composites for welding electrodes and sliding contact material is investigated through the experiments on the mechanical properties, wear resistance and electric conductivity. Various tests are performed for the Cu-TiB/sub 2/ nanocomposites with the content of TiB/sub 2/ from 2.5 to 10 wt% pure copper specimens are also tested for comparison.

Ultrafine TaC powders were synthesised by spray drying using tantalum oxalate solution. The spray dried powders were spherical shape and less than 30 in size. The powders calcined at 500 and X showed amorphous structures and phase was obtained by calcining at . The particle size and shape remains constant after calcination. The calcined spherical powders were composed of an agglomerate of primary particles under 50 nm in size. The complete formation of TaC could be achieved by heat treatment at for 6 hrs. The observed size of TaC powders by TEM was less than 200 nm.