The pleiotropic functions of Intracellular hydrophobins in aerial hyphae and fungal spores

Higher fungi can rapidly produce large numbers of spores suitable for aerial dispersal. The efficiency of the dispersal and spore resilience to abiotic stresses correlate with their hydrophobicity provided by the unique amphiphilic and superior surface-active proteins–hydrophobins (HFBs)–that self-assemble at hydrophobic/hydrophilic interfaces and thus modulate surface properties. Using the HFB-enriched mold Trichoderma (Hypocreales, Ascomycota) and the HFB-free yeast Pichia pastoris (Saccharomycetales, Ascomycota), we revealed that the rapid release of HFBs by aerial hyphae shortly prior to conidiation is associated with their intracellular accumulation in vacuoles and/or lipid-enriched organelles. The occasional internalization of the latter organelles in vacuoles can provide the hydrophobic/hydrophilic interface for the assembly of HFB layers and thus result in the formation of HFB-enriched vesicles and vacuolar multicisternal structures (VMSs) putatively lined up by HFBs. These HFB-enriched vesicles and VMSs can become fused in large tonoplast-like organelles or move to the periplasm for secretion. The tonoplast-like structures can contribute to the maintenance of turgor pressure in aerial hyphae supporting the erection of sporogenic structures (e.g., conidiophores) and provide intracellular force to squeeze out HFB-enriched vesicles and VMSs from the periplasm through the cell wall. We also show that the secretion of HFBs occurs prior to the conidiation and reveal that the even spore coating of HFBs deposited in the extracellular matrix requires microscopic water droplets that can be either guttated by the hyphae or obtained from the environment. Furthermore, we demonstrate that at least one HFB, HFB4 in T. guizhouense, is produced and secreted by wetted spores. We show that this protein possibly controls spore dormancy and contributes to the water sensing mechanism required for the detection of germination conditions. Thus, intracellular HFBs have a range of pleiotropic functions in aerial hyphae and spores and are essential for fungal development and fitness.

Study On Cutting Force and Tool Vibration For Optimization of Depth of Cut in Ultra-Precision Planing Process of the Master Mold For Retro-Reflection Film

The micro-triangular pyramid patterns are widely used in advanced optical components with retro-reflection characteristic. The performance of the retro-reflection is affected by an effective area, and it can be maximized by machined surface without defects such as edge blunt, burr, surface roughen. The ultra-precision planing process is well-known that can fabricate superior surface when the depth of cut (DOC) is applied to minimum depth above the critical value to prevent the size effect. However, it was very difficult to determine a DOC without comparing of quality of machined surfaces through the ultra-high magnification measuring instrument such as SEM. In this study, the critical DOC which is key parameter was analyzed using cutting force and tool vibration signals. These signals were converted to specific cutting resistance and frequency spectrum, respectively. As a result, spectrum frequency signal was more effective and accurate than specific cutting energy, and critical DOC was determined to 1µm. This proposed process was validated by comparing the quality variation of the machined surfaces with analysis result based on cutting signals. Finally, a master mold with area of 250mm2 for fabrication of the retro-reflection film was manufactured by applying optimized DOC, and the retro-reflection film was fabricated by press molding process. This retro-reflection film was clearly recognized at a distance of 100m from light source with low power.

Superior mediastinal tumour excision through upper partial sternotomy and chamberlain incision

Superior mediastinal mass excision can be performed by various approaches such as partial sternotomy, mini trapdoor incision, anterior cervical transsternal approach and lateral thoracotomies. However, adequate exposure especially of superior surface seems to be difficult. Total four patients of superior mediastinal mass were admitted in the department of cardiothoracic and vascular surgery, Safdarjung hospital, New Delhi between June 2019 to May 2021. All of them were operated by upper partial sternotomy with right or left chamberlain extension of incision. It is safe and effective in terms of exposure with early recovery as well as cosmesis. Hence, we advocate the use of upper partial sternotomy with left or right chamberlain incision which provides good exposure in addition to ease of patient position, vascular control and emergency institution of cardiopulmonary bypass.

Progress in the Application of Carbon Dots-Based Nanozymes

As functional nanomaterials with simulating enzyme-like properties, nanozymes can not only overcome the inherent limitations of natural enzymes in terms of stability and preparation cost but also possess design, versatility, maneuverability, and applicability of nanomaterials. Therefore, they can be combined with other materials to form composite nanomaterials with superior performance, which has garnered considerable attention. Carbon dots (CDs) are an ideal choice for these composite materials due to their unique physical and chemical properties, such as excellent water dispersion, stable chemical inertness, high photobleaching resistance, and superior surface engineering. With the continuous emergence of various CDs-based nanozymes, it is vital to thoroughly understand their working principle, performance evaluation, and application scope. This review comprehensively discusses the recent advantages and disadvantages of CDs-based nanozymes in biomedicine, catalysis, sensing, detection aspects. It is expected to provide valuable insights into developing novel CDs-based nanozymes.

Development of PosMAC® Steel and Its Application Properties

PosMAC® is a hot dipping Zn-Mg-Al coated steel sheet developed by POSCO. PosMAC®3.0 shows excellent anti-corrosion performance and is suitable for construction and solar energy systems in severe corrosive environments. PosMAC®1.5 has a superior surface quality and is preferred for automotive and home appliances. The advanced anti-corrosion properties of PosMAC® comes from a dense corroded layer which forms on coated surfaces, compared with traditional Zn coatings such as GI, GA and EG. PosMAC® steels show superior corrosion protection compared to GI coatings in cyclic corrosion tests, despite an approximate 30% reduction in coating weight. The PosMAC® has excellent application properties for the arc welding of automotive chassis. It has a heat resistance that is more robust than the GI coating, and maintains excellent corrosion protection near the welds of the chassis. Zn-Mg-Al coatings, whose chemical compositions are similar to PosMAC® coatings, have very low surface friction properties compared to the GI coating. The friction coefficient of PosMAC® is stabilized to 0.09~0.11. In contrast, the GI coating showed higher friction coefficients of 0.2~0.3 in the repeated friction test. PosMAC® would be appropriate for complex forming parts with less galling, given these low friction resistance properties. It is expected that the industrial demand for PosMAC® steel will increase in the near future, thanks to its Zn saving and high anti-corrosion performance.

Immobilization of Camel Liver Catalase on Nanosilver-Coated Cotton Fabric

Nanoparticles have the advantage of a superior surface area to volume ratio, and thus such materials are useful for enzyme immobilization. A silver nanoparticle coated cotton fabric (AgNp-CF) is used to immobilize camel liver catalase in the present work. The effect of loading levels of AgNp inside cotton fabrics on the immobilization of catalase was investigated. The results revealed that a 6 mL loading level of AgNp precursor (silver nitrate, 2 mM) at pH 8 showed the maximum immobilization efficiency (76%). The morphological properties of the cotton fabric (CF), AgNp-CF and AgNp-CF-catalase were characterized by SEM. The reusability of the immobilized enzyme was tested over ten reuses to show a 67% retained function of its initial activity. Compared with the soluble enzyme’s working pH (6.5), a rather broader working pH (6.5–7.0) was observed for the immobilized catalase. Additionally, the optimum working temperature increased from 30 for the soluble enzyme to 40 °C for the immobilized one, indicating thermal stability. The free and immobilized catalase enzyme’s Km values were 22.5 and 25 mM H2O2, respectively, reflecting the enzyme’s effective properties. The inhibitory effect of metal ions on the enzyme activity was higher toward soluble catalase than the immobilized catalase. This work has developed a method for immobilizing catalase to be useful for several applications.

Calcaneal Fracture Maps And Their Determinants

Background: Calcaneal fractures are associated with numerous complications and a poor prognosis with significant long-term quality-of-life issues, regardless of treatment. Therefore, in-depth research into the underlying mechanism of calcaneal fracture is still of great interest, with the goal of improving treatment for patients suffering from this condition. This study aimed to investigate the relationship between the distribution of calcaneal fracture lines and their determinants, especially those related to the internal structure of the calcaneus. This goal was achieved by fracture maps created by copying and stacking fracture lines as viewed from six surfaces of the calcaneus.Methods: A total of 210 consecutive patients with 226 calcaneal fractures were retrospectively analyzed. Fracture lines were copied from a reduced 3D calcaneal fracture model and stacked on calcaneal templates to generate fracture maps. The stacked images of six calcaneus surfaces were also converted into spectrograms with MATLAB to highlight the fracture frequency at specific locations.Results: There were four concentrated bands of fracture lines and two fracture hot spots on the superior surface. Three dense bands of fractures were observed on the medial surface, and four fracture bands were observed lateral to the calcaneus. Vertical fracture lines dominated the anterior calcaneal fracture map. On the posterior surface, the fracture lines appeared to be centered superiorly. All fracture locations coincided with the interfaces between the trabecular groups.Conclusions: The fracture maps showed fracture patterns and recurrent fracture zones on all calcaneal surfaces. The shape of the talus and calcaneus and the architecture within the calcaneus, especially the arrangement of the trabeculae, are essential factors for calcaneal fractures.

Study of Pattern of the Talar Articular Facets in 150 Dried Adult Human Calcanei of North Karnataka Population

Introduction: Calcaneus and talus are bones of the hind foot. Calcaneus being the largest of tarsal bones has three facets on its superior surface for articulation with the talus namely anterior, middle and posterior talar facets. Proper alignment of these two bones is essential for maintenance of the arches of foot. Variations in the talar facets of calcanei are important because they influence subtalar joint stability. In many diseases of foot such as the talocalcaneal arthritis and coalition, intra-articular fracture etc, the size, shape and relation of talus and calcaneus with each other and other bones of the foot must be considered for the external and internal fixation and for other surgical procedures. Objectives: The present work is intended to study different patterns of talar articular facets on the calcaneum to have a better understanding of anatomical elements contributing to subtalar joint stability and to correlate findings of the present study with existing literature. Materials and Methods: 150 dry adult undamaged and non-pathological human calcanei of unknown sex were obtained from museum section of department of Anatomy of various medical colleges in North Karnataka. The pattern of talar articular facets with reference to their shape and number was studied and interfacet distance between anterior and middle talar facets was measured using sliding vernier callipers. The data was subjected for statistical analysis. Results: Based on notable characteristic features, calcanei were grouped into five types:73.3% of calcanei belonged to Type I, 22% to Type II, 2% to Type III, 2% to Type IV and 0.7% to type V. Conclusion: Unique feature of the present study was that all the five types of calcanei were found. Type I being the commonest(73.3%) and Type V which is the rarest type and has been scarcely reported in the literature was also seen in one calcaneum. Pattern of talar articular facets on calcaneum exhibits racial differentiation which could be probably genetically determined. KEY WORD: Articular, Calcaneus, Facets, Talus.