Lip Formation Research Articles

Sasa veitchii extract alleviates phenobarbital‐induced cell proliferation inhibition by upregulating transforming growth factor‐beta 1

AbstractAimCleft lip is a common congenital disease, accompanied by a complicated etiology. Medical exposure in women is one of the reasons leading to cleft lip. Phenobarbital is a major drug used for the treatment of epilepsy and has been reported to induce cleft lip, with or without cleft palate. This study aimed to explore the protective effects of Sasa veitchii extract (SE) against phenobarbital‐induced inhibition of human lip fibroblast (JCRB9103) cell proliferation.MethodsWe evaluated the cell viability of JCRB9103 cells after 48 h of phenobarbital treatment. We examined the rescue experiment using SE, sodium copper chlorophyllin, or recombinant transforming growth factor‐beta 1. Western blotting was performed to identify key proteins involved in lip formation in JCRB9103 cells.ResultsPhenobarbital treatment decreased the cell viability of JCRB9103 cells in a dose‐dependent manner. Cotreatment with SE or sodium copper chlorophyllin alleviated phenobarbital‐induced inhibition of cell viability in JCRB9103 cells. SE treatment upregulated the transforming growth factor‐beta 1 level, and transforming growth factor‐beta 1 protected against phenobarbital‐induced inhibition of cell proliferation.ConclusionsThese results suggest that phenobarbital‐induced inhibition of cell proliferation was restored by sodium copper chlorophyllin present in SE via the regulation of transforming growth factor‐beta 1.

Experimental study on slurry erosion wear behaviour of 2205 duplex stainless steel through integrated Taguchi approach and artificial neural network

Slurry erosion due to particle entrainment poses a significant threat to slurry handling components, leading to reduced performance and shorter service life. The ferritic-austenitic microstructure of 2205 duplex stainless steel (DSS) offers resistance to erosion and corrosion in harsh environments. This study investigated the slurry erosion wear response of 2205 DSS, focusing on parameters, such as: angle of impingement, impact velocity, slurry concentration, erodent size, and stand-off distance. A Taguchi experimental design approach, along with analysis of variance (ANOVA), was employed to design the experiments and identify the most significant factors. ANOVA results revealed that impact velocity and slurry concentration were the most influential parameters affecting mass loss, while erodent size and impact velocity significantly influenced surface roughness. Additionally, an artificial neural network model was used to estimate output responses, and the model's predictions were compared with experimental results. The surface and sub-surface characteristics of the eroded samples were analysed using X-ray diffraction, microhardness testing, and optical profilometry. The material removal mechanisms were studied using scanning electron microscopy, revealing ductile erosion behaviour in 2205 DSS. Micro-cutting, ploughing, lip formation, and indentation were identified as the primary methods of material removal in 2205 DSS.

Effect of V-shaped Side Groove on Shear Lips Formation of Aluminium Alloy 6061 by Charpy Impact Test

This study investigates the effect of V-shaped side grooves on shear lip formation in aluminium alloy 6061 through Charpy impact testing. Aluminium is used in machines and industry as a structural component due to its mechanical properties, lightweight characteristics, easy fabrication, and high specific strength. The presence of a V-shaped side groove alters the stress distribution during impact, potentially influencing the deformation behaviour and fracture characteristics of the material. In this work, the impact tests were conducted on specimens with and without a V-shaped side groove, and the resulting shear lips formation was analysed. The findings reveal that the V-shaped side groove minimises shear lip formation compared to specimens without side grooves. This can be attributed to the surface morphology, which shows a lesser shear lip area with an increasing side groove depth ratio. A smaller shear lips area in Charpy impact tests signifies reduced plastic deformation near the groove or notch region. It indicates the material’s fracture characteristic has lower ductility and limited ability to deform plastically before a fracture occurs. This implies decreased energy absorption capacity, equated to impact energy, and an increased likelihood of brittle fracture behaviour as the side groove depth ratio increases. The micrograph of the fracture surface shows dimples, shear, and cleavage patterns.

Slurry and liquid impingement erosion behavior of low-temperature plasma carburized AISI 420 martensitic stainless steel

The impact of plasma carburizing treatment on the erosion wear resistance of AISI 420 martensitic stainless steel (MSS) was studied. Experiments were carried out varying a broad spectrum of erosion parameters, including impact velocity, impact angle, and exposure duration. Both slurry and liquid impingement erosion were employed in the experiments, with testing conducted using both distilled water and saline solutions to assess the combined effects of corrosion and erosion wear. Compared to untreated samples, a significant improvement in the erosion wear resistance of AISI 420 MSS due to low-temperature plasma carburizing treatment was observed for all tested conditions. The observed performance enhancement can be attributed to the formation of the carburized layer, constituted of the α'C and Fe3C phases. Results also highlighted that the severity of the tribosystem was significantly influenced by the test solution characteristics. A marginal increase in severity was observed upon introducing the saline solution, while a more substantial severity increase occurred with the addition of solid particles in the test fluid. The specimens' mass loss was increased by increasing impact velocity, following a simple potential relationship, and with impact angle, following a first-degree linear equation. In the case of the exposure time, the mass loss curves depended on the test environment. For solutions containing quartz particles, an additional final stabilization stage was observed in addition to the acceleration stage observed in the absence of abrasive component. This phenomenon was attributed to surface work hardening induced by the impact of solid particles. Regarding wear mechanisms, samples tested only with distilled water displayed erosion flow marks. Those containing distilled water and NaCl exhibited not only flow marks but also pits. Lastly, solutions containing solid particles additionally presented features of plastic deformation, lip formation, craters, indentations, and extruded material.

Investigation of aqueous slurry erosion-corrosion behaviour of Tantalum in different pH solutions

Erosion-corrosion behaviour of pure Tantalum (Ta) was investigated using corrosive slurry solutions (pH 4, 7, and 10) containing 7 wt% SiC as erodent particles. Tests were carried out using an impinging jet erosion-corrosion apparatus with a jet velocity of 5 ms−1 and at two impact angles (30° and 90°). Under particle bombardment conditions, a marked reduction in corrosion resistance offered by Ta was observed amid a significant cathodic shift in the ECorr values for all pH values investigated. Results showed that interaction between erosion and corrosion was higher under 30° impact leading to a higher rate of material removal. On the contrary, negative synergism was observed for experimental conditions of normal impact for pH 7 and pH 10. Scanning electron microscopy studies revealed typical ductile erosion mechanisms of material removal which consisted of dominating micro-cutting for 30° and plastic deformation resulting in lip formation for normal impact angle. These appeared to be assisted by dissolution of weakened areas and passive layer removal as corrosion mechanisms. Potentiostatic erosion-corrosion experiments were utilised for calculation of synergistic and antagonistic effects and have been presented in the paper.

Improving erosion resistance through solution treatment of nitronic and martensitic steels for slurry erosive applications

Erosive wear is a general phenomenon in moving underwater parts of various types of equipment and slurry transportation. Materials with high erosion resistance are recommended for such applications. Currently used martensitic steel can be replaced with nitrogen containing austenitic stainless-steel grades 21-4 N and 23-8 N due to higher erosion resistance. This paper investigates the pathway to enhance the slurry erosion resistance of nitronic steels and evaluates its feasibility to replace currently used martensitic steel for heavy slurry erosive applications. Solution treatment was observed as a potential pathway to improve slurry erosion resistance and mechanical properties of the selected steels where specimens were subjected to solution treatment at 950 °C and 1150 °C. After the solution treatment, reduced carbide volume and fine distribution in the nitrogen alloyed austenitic microstructure resulted in higher erosion resistance. Nitronic steel grades resulted in low cumulative weight loss or high erosion resistance than martensitic steel for as-received and solution-treated samples. Solution treatment resulted in a maximum reduction in cumulative weight loss for martensitic steel, 21-4 N and 23-8 N was 10 wt%, 14.2 wt%, and 18.18 wt%, respectively, at 90° impingement angle. The erosion mechanisms observed at different impingement angles were different for both nitrogen alloyed and martensitic steels. The erosion mechanism was primarily deformation at 90° impingement angle, whereas at 30° impingement angle, the mechanism was lip formation, detachment, and ploughing.

Investigations on erosion performance of carbon fiber–epoxy-based composite adhesion on 16Cr5Ni steel

This work presents a novel insight into slurry erosion behavior of thin layer of carbon fiber–epoxy-based composite adhered on 16Cr5Ni steel (adhesive coating) to evaluate its viability as a feasible candidate for slurry erosion applications. Experiments were conducted on a laboratory-developed slurry erosion test rig under accelerated conditions to study the effect erosion parameters namely slurry concentration, impact angle, and impact velocity. Under all the experimental conditions, adhesive coating showed better slurry erosion resistance in comparison with bare 16Cr5Ni steel specimens. Scanning electron microscopy analysis revealed that in the case of bare 16Cr5Ni steel; ploughing, micro-cutting, crater, plastic deformation, and lip formation were identified as main mechanism responsible for slurry erosion, whereas in the case of adhesive coating; pitting, cracking, fracturing, and shearing-off were found to be mainly responsible for material loss. It implies that adhesive coating showed a brittle mode of failure under slurry erosion conditions, whereas 16Cr5Ni steel exhibited a ductile mode of erosion.

Orchid NAC Transcription Factors: A Focused Analysis of CUPULIFORMIS Genes

Plant transcription factors are involved in different developmental pathways. NAC transcription factors (No Apical Meristem, Arabidopsis thaliana Activating Factor, Cup-shaped Cotyledon) act in various processes, e.g., plant organ formation, response to stress, and defense mechanisms. In Antirrhinum majus, the NAC transcription factor CUPULIFORMIS (CUP) plays a role in determining organ boundaries and lip formation, and the CUP homologs of Arabidopsis and Petunia are involved in flower organ formation. Orchidaceae is one of the most species-rich families of angiosperms, known for its extraordinary diversification of flower morphology. We conducted a transcriptome and genome-wide analysis of orchid NACs, focusing on the No Apical Meristem (NAM) subfamily and CUP genes. To check whether the CUP homologs could be involved in the perianth formation of orchids, we performed an expression analysis on the flower organs of the orchid Phalaenopsis aphrodite at different developmental stages. The expression patterns of the CUP genes of P. aphrodite suggest their possible role in flower development and symmetry establishment. In addition, as observed in other species, the orchid CUP1 and CUP2 genes seem to be regulated by the microRNA, miR164. Our results represent a preliminary study of NAC transcription factors in orchids to understand the role of these genes during orchid flower formation.

A comprehensive parametric study on abrasive waterjet trepanning of Al-6061 alloy

ABSTRACT Abrasive waterjet (AWJ) can be used to realize holes of any size and shape in difficult-to-machine ductile materials with negligible heat-affected zone by simply changing the jet path. In this study, the influence of various process parameters, such as waterjet pressure (P), jet traverse speed (), abrasive mass flow rate (m a ) on the AWJ-trepanned hole’s geometrical features (diameter, taper angle, profile), form characteristics (circularity error, cylindricity error), quality measures (damage region, edge radius, burr formation, uncut material, surface morphology), and material removal mechanism in Al-6061 alloy is studied. The results show that higher P and m a at lower are desirable for achieving nominal geometrical features, minimal form error, burr length, and uncut material. Damage region reduces with the decrease in P and m a at higher . Edge radius reduces with the increase in P at lower and m a . The micrographs showed that the initial damage region is uniform at higher P and lower . Better surface quality is obtained at higher P and m a as lip formation and material pile-up are minimum. Material fracture and cracks in the vicinity of the burr are observed. Based on the mean response analysis, near-optimal parameters are suggested for efficient trepanning.

Effect of build orientation on wear and erosion behavior of maraging steel processed by powder bed fusion using laser beam (PBF-LB)

The wear and erosion behavior of additively manufactured maraging steel with built orientations of 0°, 45° and 90° were investigated and compared with conventional (cast and hot rolled) samples. To investigate the effect of heat treatment, processed samples were subjected to solution treatment and ageing. As-built (AB) and heat-treated (HT) samples were wear-tested at various loads of 20N, 40N and 80N, at constant disc speed and specific sliding distance. Erosion tests were performed at 90° impingement angle for 40 min with erosion discharge rate of 4.5 g min−1, wear rate was found increasing with the increase in load from 20N to 80 N, and was found affected by build orientation, mainly in the as-built additive samples. In both, as built as well heat-treated conditions, 90° oriented samples were found more wear-resistant. However, wear resistance of the heat-treated samples was observed to be relatively higher as compared to that of as-built samples. Coefficient of friction (COF) decreased with increase in load, in both as built as well heat-treated conditions. Erosion resistance of the as-built (AB) and heat-treated (HT) samples in 0° orientation was higher than that of other build orientations. Prior to heat treatment, erosion resistance of the conventional samples was inferior to that of additive samples, due to comparatively coarser microstructure; however, after the heat treatment, erosion resistance was increased. Worn and eroded samples were examined under SEM and AFM. At low load of 20 N, abrasive wear by ploughing and at high load of 80N, adhesive wear was noticed. Erosion occurred mainly by lip formation and plastic deformation.

Slurry Erosion Behavior of Thermally Sprayed Nano YSZ Reinforced WC-10Co-4Cr Ceramic Nanocomposite Coatings

The presence of nanoparticles in the conventional coatings improves their strength by increasing the microhardness and reducing the porosity. The nanocomposite coatings play a significant role in increasing the erosion resistance. The purpose of this study is to observe the erosion behavior of nano yttria stabilized zirconia (Y2O3/ZrO2; YSZ) reinforced WC-10Co-4Cr ceramic nanocomposite coatings. The WC-10Co-4Cr conventional coating powder, and 95% and 90% of WC-10Co-4Cr reinforced with 5% and 10% of nano YSZ powders, coated on CA6NM steel using a high-velocity oxygen fuel (HVOF) spraying process. The Taguchi method using an L9 orthogonal array was applied for experimental design. Erosion test rig was used to perform erosion experiments at various levels of selected parameters. The results of erosion experiments and analysis of variance (ANOVA) for the conventional and nanocomposite coatings revealed that impact velocity performs a significant role in the material loss, followed by slurry concentration, average particle size, and impingement angle. Scanning electron microscopy (SEM) analysis of eroded samples revealed that cracks, protuberances, deep craters, spalling, ploughing, micropores, microcutting, lip formation, chip formation and microcracks are mainly responsible for the erosion of substrate material and different types of coatings. Inclusion of nanoparticles of YSZ into the WC-10Co-4Cr microparticles increased the microhardness and decreased the porosity of the nanocomposite coatings. Thus, the silt particles cannot penetrate more deeply into the metal surface and provided high resistance to erosion. It was observed that 95% (WC-10Co-4Cr) + 5% YSZ and 90% (WC-10Co-4Cr) + 10% YSZ ceramic nanocomposite coatings exhibits higher resistance to erosion in comparison with WC-10Co-4Cr coating and substrate material, due to better mechanical properties.

Kinematic Analyses of Metallic Plate Perforation by Penetrators with Various Nose Geometries

This study analyses kinematics of a metallic plate perforation by a penetrator with truncated ogive nose geometry to find solutions also to blunt, conical, ogive, and hemi-spherical nosed penetrators. Plugging, ductile hole enlargement, dishing, and petal forming failure modes are used in the analyses. Acceleration throughout perforation is calculated by using the related failure mode, analytical model, and the target-penetrator interaction geometry. Depending on the failure model; back lip and front lip formation during ductile hole enlargement, plug formation during plugging, and deflection of target plate during dishing is also analysed. Analyses are based on projectile’s equation of motion, momentum and energy equations, and projectile-target plate interactions. The analyses results for selected cases, with the impact velocity range 215-863 m/s, are compared with the test data. The residual velocity estimation for a strike velocity is close to the related test data with an error of 0.3-2.2 %, except for conical nosed penetrators at impact velocities approaching the ballistic limit velocity

A Systematic Review of the Role of Mitochondria in Cleft Pathology: A Forgotten General?

Orofacial clefts (OFC) are one of the most common birth defects that affects the lip, palate, or lip and palate of an infant. The deterioration of clefts is multifactorial involving multiple genes, various interactions from environmental factor and most forgotten, mitochondrial abnormality. The aim of this review is to highlight the importance of mitochondrial activity related to non-syndromic OFC deformity. Despite its important role in cells, the study on mitochondrial activity in cleft pathology was scarce and almost forgotten compared to other genetic investigations. This systematic review was completed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. The literature search was done via the following databases: Google Scholar, Pubmed and Scopus with a total of nine studies of mitochondrial abnormalities were included. We hypothesise that mitochondria play an important role in early craniofacial development. A decreased in its function or activity may result in cleft lip formation. Hence, we would like to shed light on the remarkable role of mitochondria activity in the pathogenesis of non-syndromic OFC.

High-Temperature Solid Particle Erosion Behavior of Laser Powder Bed Fused Inconel 718

Abstract The failure of turbine blades due to solid particle erosion is a serious concern in aviation applications. This research investigates the solid particle erosion behavior of laser powder bed fused IN718 alloy for the effect of temperature (400 °C, 500 °C, and 600 °C) and impact angle (45 deg and 90 deg) in a gas-jet erosion setup. The erosion rate progressively increased with the test temperature and it is significantly higher in the 45 deg eroded samples. The eroded samples were characterized for residual stress distribution, surface topography, and surface roughness using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and 3D optical profilometer. Compressive residual stress is evident in all eroded samples, and higher residual stress is measured in the 90 deg eroded samples. Ploughing, crater lip formation, and cracking are the erosion features observed in the 45 deg eroded samples. In comparison, localized plastic deformation, platelet mechanisms, and cracked ridges are observed in the 90 deg eroded samples. Crack formation at 600 °C test condition is attributed to severe erosion degradation in both the impact conditions (45 deg and 90 deg). The as-printed and solution-double aged samples were thoroughly investigated for microstructure and microhardness distribution at the region parallel and perpendicular to the build direction.

Downregulation of WNT8A, LRP5, LRP6 and FGF8 in Malay Non-Syndromic Cleft Lip and/or Palate Patients

Non-syndromic cleft lip and/or palate (NSCL/P) is a one of the most common birth defects occurs as a result of multi-factorial determinants such as genetic and environmental factors. Genetic factor has been studying widely across different population in identifying genes causing cleft defects. This study aims to validate the role of fibroblast growth factors (FGFs) and signalling molecules Wingless-type (Wnt) to the occurrence of cleft lip and/or palate among Malay population. Tissue skin was obtained from consented NSCL/P patients who underwent the cleft lip repair operation at the upper lip skin area and non NSCL/P individual was obtained from patient having traumatic injury at the lip area as a control. Expression pattern of FGF8, FGF10, Wnt8a, and LRP5/6 were tested and validated using Western Blot (WB) and quantitative Reverse Transcriptase-PCR (qRT-PCR). The fold change difference of FGF8 (0.614 ± 0.1012-fold), FGF10 (0.7188 ± 0.1017-fold) and Wnt8a protein (0.9051 ± 0.0142-fold) was downregulated by 1-fold in cleft lip (CL) tissues compared to the normal meanwhile LRP5/6 protein (1.2201 ± 0.1404-fold) was found upregulated by 1-fold. Validation testing confirmed that expression of FGF8 (p=0.014), Wnt8a (0.0762 ± 0.0227), LRP5 (0.3577 ± 0.1362) and LRP6 (0.3093 ± 0.2541) were significantly reduced in CL tissues compared to normal. This is the first study identified defective regulation of Wnt8a, LRP5, LRP6 and FGF8 in NSCL/P among Malays. These novel findings clearly explained the important role of growth factors FGF and Wnt signalling pathway in lip and palate formation during craniofacial development.

Wear performance analysis and characterization of HVOF deposited Ni–20Cr2O3, Ni–30Al2O3, and Al2O3–13TiO2 coatings

The present study was aimed to analyze a slurry erosion failure of SS316L steel coated with high-velocity oxygen-fuel coatings using Ni–20Cr2O3, Ni–30Al2O3, and Al2O3–13TiO2. Slurry erosion experiments were performed using a pot erosion tester for the time duration of 90–180 min at different velocities. The sand particles were used as an erodent to study the erosion wear phenomenon. The concentration of the two-phase slurry was kept in the range of 30–60 wt%. It was seen from the results that speed of rotation, concentration (wt%), and time duration play a vital role in the erosion wear rate of the coated and uncoated AISI 316L. Except for the impingement angle, an increase in the value of all parameters increases the deterioration of parent material with and without coatings. The deterioration rate of the parent material was improved by using coatings. Erosion performance of the AISI 316L was improved by an average of 43.06%, 23.55%, and 13.73% respectively with the deposition of Ni–20Cr2O3, Ni–30Al2O3, and Al2O3–13TiO2 HVOF coatings while all the parameters were varied from lowest to the highest value. Microscopically, the microcutting, smear regions, debonding, lip formation, fracturing, and cracks wear mechanisms occur in Ni–20Cr2O3 HVOF coating. The Ni–30Al2O3 HVOF coating underwent debonding, crater, microcutting, fracturing, ploughing, and lip formation. The major wear mechanisms in Al2O3–13TiO2 coatings are identified as smear, crater, pitting, microcutting, debonding, fracturing, cracks, ploughing, and lip formation.

Erosion behaviour of HVOF sprayed Alloy718-nano Al2O3 composite coatings on grey cast iron at elevated temperature conditions

The current study investigates the erosion performance of high-velocity oxy-fuel (HVOF) sprayed Alloy718-nanoAl2O3 composite coatings on cast iron. The effect of the addition of nano-Al2O3 reinforcement in the Alloy718(AL718) matrix was studied by varying the nano-Al2O3 content from 10wt% to 30wt%. Initially, the microstructural and phase analysis of the developed coatings was conducted. The as-deposited coating in the AL718matrix showed the well-scattered nano-Al2O3particles in the AL718 matrix. The highest micro-hardness was found to be1296 ± 40 HV0.2 for Alloy718%-30%nanoAl2O3 (30N) coating, which is around 3.56 times higher than the grey cast iron (GCI) substrate. The air-jet erosion test was conducted at 900 °C at both low and high degrees impact angles (30° and 90°). The 30N coating showed the maximum erosion resistance due to the higher micro-hardness and fracture toughness amongst all the deposited coatings. The increased nano-Al2O3 content enhanced the erosion resistance of the coatings by providing dispersion strengthening to the matrix. The formation of cavities, ploughing, lip formation and micro-cutting were observed in all deposited coatings at 30° impact angle as wear mechanism. The formation of cracks, craters and pullout was the responsible wear mechanism at 90° impact angle for all deposited coatings. The developed coatings showed mixed behaviour of ductile and brittle mode of failure at 30° impact angle and brittle mode of failure at 90° impact angle for 30N coating.

Transcriptomics unravels molecular players shaping dorsal lip hypertrophy in the vacuum cleaner cichlid, Gnathochromis permaxillaris

BackgroundTeleosts display a spectacular diversity of craniofacial adaptations that often mediates ecological specializations. A considerable amount of research has revealed molecular players underlying skeletal craniofacial morphologies, but less is known about soft craniofacial phenotypes. Here we focus on an example of lip hypertrophy in the benthivorous Lake Tangnayika cichlid, Gnathochromis permaxillaris, considered to be a morphological adaptation to extract invertebrates out of the uppermost layer of mud bottom. We investigate the molecular and regulatory basis of lip hypertrophy in G. permaxillaris using a comparative transcriptomic approach.ResultsWe identified a gene regulatory network involved in tissue overgrowth and cellular hypertrophy, potentially associated with the formation of a locally restricted hypertrophic lip in a teleost fish species. Of particular interest were the increased expression level of apoda and fhl2, as well as reduced expression of cyp1a, gimap8, lama5 and rasal3, in the hypertrophic lip region which have been implicated in lip formation in other vertebrates. Among the predicted upstream transcription factors, we found reduced expression of foxp1 in the hypertrophic lip region, which is known to act as repressor of cell growth and proliferation, and its function has been associated with hypertrophy of upper lip in human.ConclusionOur results provide a genetic foundation for future studies of molecular players shaping soft and exaggerated, but locally restricted, craniofacial morphological changes in fish and perhaps across vertebrates. In the future, we advocate integrating gene regulatory networks of various craniofacial phenotypes to understand how they collectively govern trophic and behavioural adaptations.

Erosion behavior of laser cladded Colmonoy-6 + 50%WC on SS410 steel under accelerated slurry erosion testing

Erosion due to slurry has an indispensable effect on the lifespan and operating efficiency of hydro machine components. To mitigate this effect, laser cladding may prove as a cost-effective choice to improve the surface properties of various hydro machine components. In this research work, a laser cladding of Colmonoy-6 + 50%WC powder on the surface of SS410 steel was deposited using high-power diode laser at optimized levels of operating parameters. The deposited coating was characterized with regard to different mechanical and metallurgical properties. The effect of various factors such as slurry concentration, erodent particle size, impact velocity, and impact angle on slurry erosion behavior of uncoated and laser cladded substrate was analyzed. The Colmonoy-6 + 50%WC cladded specimens exhibited significantly better slurry erosion resistance in comparison with uncoated SS410 steel specimens under all slurry erosion conditions. Impact velocity was observed to be a maximum contributor to slurry erosion, followed by impact angle, average particle size and slurry concentration. The SEM micrographs of eroded cladded surfaces showed signatures of lip formation & fracture sites, micro-cutting, ploughing, and wear marks at a shallow impact angle in Colmonoy-6 pool, however, for normal impact, the existence of cracks in WC particles were observed.

Four DEF-like and two AGL6-like MADS-box genes display possible roles in perianth formation in Rhynchostylis retusa

Rhynchostylis retusa (L.) Blume is a popular and scarce orchid species with attractive flowers arranged in a racemose cluster. To study this flower’s complex floral perianth formation, MADS-box genes that play an important role in flower morphogenesis were investigated. Four B-class DEF-like MADS-box genes, RrDEF1, RrDEF2, RrDEF3, and RrDEF4, and two E-class AGL6-like MADS-box genes, RrAGL6-1 and RrAGL6-2, were identified, and their expression was characterized by qRT-PCR. These genes were expressed in every developmental stage of reproductive organs but not in the vegetative leaves, except for RrDEF2. Most of these genes revealed similar expression patterns in stage 3 and mature flowers. Higher RrDEF1 and RrAGL6-1 expression was detected in the sepals and petals rather than the lips, while RrDEF3, RrDEF4, and RrAGL6-2 were highly expressed in the lips but exhibited low expression in the sepals. RrDEF3 was also strongly expressed in petals. These gene expression patterns supported current profiles involving sepal/petal/lip determination, with RrDEF1 and RrAGL6-1 promoting sepal/petal formation, while RrDEF3, RrDEF4, and RrAGL6-2 promoted lip formation. Our findings support revised ‘orchid code’ and ‘perianth code’ hypotheses in which floral organs are regulated by combined levels of expression from each clade of DEF-like genes and AGL6-like genes. These four RrDEF and two RrAGL6 genes promote and enrich our knowledge and understanding concerning the floral development of orchids.