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Particulate reinforced aluminium matrix composites (AMCs) were prepared by stir cast method and their wear and corrosion properties were investigated. The structural and morphological properties of the AMCs were examined by XRD and SEM analysis. EPMA validates the dispersion of SiC and MoS2 particles in the metal matrix. The wear of the aluminium alloy Al6063-T6(AM-0), 3% nano SiC reinforced composite(AMC-1) and 3% nano SiC with 3% micro MoS2 reinforced composite (AMC-2) were studied using ASTM G99–95 standard. The wear rates of AMC- 1 and AMC-2 were relatively lesser than that of AM-0 at all applied loads of 10 N, 20 N and 30 N. However, the friction coefficients of the AMCs were found to be higher than that of AM-0. Particulates micro fracture is found to be the predominant wear mechanism associated with 3 body abrasive wear as indicated by the SEM micrographs of the worn out surfaces. ASTM-B117 has been used to find out the effect of micro-constituents on the corrosion behaviour of AMC-1 and AMC-2 composites. The significant improvements in the corrosion resistance was observed in AMC-2 due to SiC and MoS2 reinforcement. The SEM images of corroded surfaces of the composite illustrate formation of productive layer for reducing the corrosion rate of the composites. [ABSTRACT FROM AUTHOR]

Identifying plant sexual dimorphic traits is critical in advancing our knowledge on plant-pollinator interactions. For example, dimorphism in floral colors, or sexual dichromatism, is a crucial mediator of pollinator choice on foraging decisions. We studied Cylindropuntia wolfii, a model system, with diverse flower colors and a functionally dioecious sexual system. However, evidence suggests that sexual reproduction is limited in this species as it has a low seed set especially in naturally pollinated fruits. Thus, it is critical to this native species' conservation to investigate its relationship with pollinators. Our goals were to: (a) investigate the sexual dimorphism including the sexual dichromatism in the flowers of the cactus, and (b) determine whether sexually dimorphic traits affect the pollinator attraction of both the sexes. We measured several quantitative and qualitative traits and compared them between male and female flowers. Then we recorded the pollinator visitation rate in nature for both sexes and tracked pollinator color preference using fluorescent dyes as pollen analogues. Our study showed that male flowers of C. wolfii are bigger and brighter, and they attract more potential pollinators than females, supporting the hypothesis that sexual dimorphism influences pollinator visitation preference. Fluorescence dichromatism, in which female flowers' anthers fluoresce more than male flower anthers suggest this could be female flowers' strategy to compensate for their dark colors and small size. The results from this study showed that C. wolfii exhibits sexual dichromatism and fluorescence dichromatism, which is a novel finding in plant research., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: In certain unisexual flowers, non-functional sexual organs remain vestigial and unisexuality can be overlooked leading to the ambiguous description of the sexual systems. Therefore, to accurately describe the sexual system, detailed morphological and developmental analyses along with experimental crosses must be performed. Cylindropuntia wolfii is a rare cactus endemic to the Sonoran Desert in southern California and northern Baja California that was described as gynodioecious by morphological analysis. The aims of our project include accurately identifying the sexual system of C. wolfii using histological and functional studies and characterizing the developmental mechanisms that underlie its floral development., Methods: Histological analyses were carried out on different stages of C. wolfii flowers and controlled crosses were performed in the field., Result: Our results identified C. wolfii to be functionally dioecious. The ovule and anther development differed between staminate and pistillate flowers. In vivo pollen germination tests showed that the pollen of staminate and pistillate flowers were viable and the stigma and style of both staminate and pistillate flowers were receptive. This suggests that there are no genetic or developmental barriers in the earlier stages of pollen recognition and pollen germination., Conclusions: Despite being functionally dioecious, we observed that functionally pistillate individuals produced fruits with a large number of aborted seeds. This implies that not only does this species have low reproductive success, but its small population sizes may lead to low genetic diversity., (© 2022. The Author(s).)

Lyme disease is commonly diagnosed by serologic response to Borrelia burgdorferi and related species, but the relationship between serologic targets and clinical features is unknown. We developed a multiantigen Luminex-based panel and evaluated IgG responses in 527 children 1 to 21 years of age assessed for Lyme disease across 4 Pedi Lyme Net emergency departments, including 127 Lyme cases defined by either an erythema migrans (EM) lesion or positive C6 enzyme immunoassay followed by immunoblotting and 400 patients considered clinical mimics. Of 42 antigens tested, 26 elicited specific reactivity in Lyme patients without marked age-dependent variation. Children with single EM lesions typically lacked Borrelia -specific IgG. By principal-component analysis, children with early disseminated and late Lyme disease clustered separately from clinical mimics and also from each other. Neurological disease and arthritis exhibited distinct serologic responses, with OspC variants overrepresented in neurological disease and p100, BmpA, p58, and p45 overrepresented in arthritis. Machine learning identified a 3-antigen panel (VlsE_Bb, p41_Bb, and OspC_Bafz) that distinguished Lyme disease from clinical mimics with a sensitivity of 86.6% (95% confidence interval [CI], 80.3 to 92.1) and a specificity of 95.5% (95% CI, 93.4 to 97.4). Sensitivity was much lower in early Lyme disease (38.5%; 95% CI, 15.4 to 69.2). Interestingly, 17 children classified as Lyme mimics had a positive 3-antigen panel, suggesting that more comprehensive serologic analysis could help refine Lyme diagnosis. In conclusion, multiplex antigen panels provide a novel approach to understanding the immune response in Lyme disease, potentially helping to facilitate accurate diagnosis and to understand differences between clinical stages.

We have investigated the impact of recognized biogeographic barriers on genetic differentiation of grey box ( Eucalyptus moluccana ), a common and widespread tree species of the family Myrtaceae in eastern Australian woodlands, and its previously proposed four subspecies moluccana , pedicellata , queenslandica , and crassifolia . A range of phylogeographic analyses were conducted to examine the population genetic differentiation and subspecies genetic structure in E. moluccana in relation to biogeographic barriers. Slow evolving markers uncovering long term processes (chloroplast DNA) were used to generate a haplotype network and infer phylogeographic barriers. Additionally, fast evolving, hypervariable markers (microsatellites) were used to estimate demographic processes and genetic structure among five geographic regions (29 populations) across the entire distribution of E. moluccana . Morphological features of seedlings, such as leaf and stem traits, were assessed to evaluate population clusters and test differentiation of the putative subspecies. Haplotype network analysis revealed twenty chloroplast haplotypes with a main haplotype in a central position shared by individuals belonging to the regions containing the four putative subspecies. Microsatellite analysis detected the genetic structure between Queensland (QLD) and New South Wales (NSW) populations, consistent with the McPherson Range barrier, an east-west spur of the Great Dividing Range. The substructure was detected within QLD and NSW in line with other barriers in eastern Australia. The morphological analyses supported differentiation between QLD and NSW populations, with no difference within QLD, yet some differentiation within NSW populations. Our molecular and morphological analyses provide evidence that several geographic barriers in eastern Australia, including the Burdekin Gap and the McPherson Range have contributed to the genetic structure of E. moluccana . Genetic differentiation among E. moluccana populations supports the recognition of some but not all the four previously proposed subspecies, with crassifolia being the most differentiated., Competing Interests: None declared., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Background: During repair of tetralogy of fallot (TOF) we modified surgical strategies to preserve the valve and annulus if the pulmonary valve leaflets are pliable and not significantly dysplastic., Methods: Initially, the repair was done from the main pulmonary artery (Group-1, 215 patients) and later through an additional incision in the infundibulum of the right ventricle (Group-2, 73 patients). Recently, we changed the approach to commissurotomy of the fused leaflets by releasing the supra valvar tethering and delamination of the cuspal apparatus till the base to improve the mobility of the cusps and do a controlled commissurotomy (Group-3, 14 patients). With delamination, we could extend the limit of the repair to a z-score of -3.5., Results: There was no hospital mortality; two patients died at home after discharge. A mean follow-up of 42.01 months ± 19.25 is available for 198 patients (92%) for group 1, 16.03 ± 7.45 for group 2, and 4.07 ± 2.09 for group 3. The re-intervention-free survival is 94.4% in group 1. The z value improved from -3 (-3--2) to -1.2 (-3 - 0), P = 0.001 in Group 1, from -2.8 (-3--2.4) to -1 (-1.1--0.7), P = 0.001 in Group 2 and from -3 (-4--3) to -1, P = 0.001 in Group 3. In all the groups, there was trivial or mild pulmonary regurgitation., Conclusions: During repair of TOF, adequate valve/annulus sparing is possible if the repair is done from both the main pulmonary artery and infundibular incisions using the delamination technique., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Annals of Pediatric Cardiology.)

Although widely prevalent, Lyme disease is still under-diagnosed and misunderstood. Here we followed 73 acute Lyme disease patients and uninfected controls over a period of a year. At each visit, RNA-sequencing was applied to profile patients' peripheral blood mononuclear cells in addition to extensive clinical phenotyping. Based on the projection of the RNA-seq data into lower dimensions, we observe that the cases are separated from controls, and almost all cases never return to cluster with the controls over time. Enrichment analysis of the differentially expressed genes between clusters identifies up-regulation of immune response genes. This observation is also supported by deconvolution analysis to identify the changes in cell type composition due to Lyme disease infection. Importantly, we developed several machine learning classifiers that attempt to perform various Lyme disease classifications. We show that Lyme patients can be distinguished from the controls as well as from COVID-19 patients, but classification was not successful in distinguishing those patients with early Lyme disease cases that would advance to develop post-treatment persistent symptoms., Competing Interests: MWE and MJM were employees of Ibis Biosciences, an Abbott Company, which developed the PCR/ESI-MS assays and instrumentation used in these studies; assays described are for research use only. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Clarke, Rebman, Bailey, Wojciechowicz, Jenkins, Evangelista, Danieletto, Fan, Eshoo, Mosel, Robinson, Ramadoss, Bobe, Soloski, Aucott and Ma'ayan.)

Background: The optimal surgical management of patients with transposition of the great arteries (TGA), ventricular septal defect (VSD), and left ventricular outflow tract obstruction (LVOTO) is debatable. This is our initial experience with pulmonary root translocation (PRT), a technique that aims to preserve the pulmonary valve function., Methods: From July 2012 to October 2019, 16 patients underwent anatomical repair for TGA, VSD, and LVOTO. The median age was 12 months (range: 7 months to 13 years), and the median weight was 7.75 kg (range: 5.6-29.5 kg). Thirteen patients had a diagnosis of d-TGA and three had congenitally corrected transposition of the great arteries (cc-TGA). The surgical technique involved PRT from the left ventricle (LV) to the right ventricle and routing the LV to the aorta. The left ventricular outflow tract orifice resulting from the pulmonary root extraction was closed with a pericardial patch. In patients with cc-TGA, an atrial switch operation was added. A bidirectional Glenn was necessary in four patients with a long LV to aorta tunnel. One patient required a transannular patch to reconstruct the right ventricular outflow tract (RVOT)., Results: The median follow-up was 27 months. There was one hospital death due to residual mitral regurgitation. One patient died at home four months after hospital discharge. The remaining patients are doing well with adequate RVOT function and no valve regurgitation., Conclusions: Complete correction of TGA, VSD, and LVOTO using PRT was achieved with acceptable risk in patients with pliable and nondysplastic pulmonary valve. The translocated pulmonary root performed well in this short follow-up.

Deep hypothermic circulatory arrest (DHCA) technique has been an important armamentarium in the correction of congenital heart diseases. There have been many controversies and concerns associated with DHCA, particularly neurological damage. Selective ante grade cerebral perfusion (SACP) was introduced as an adjunct to DHCA with the objective of limiting the neurologic injury during aortic arch repairs. Over the past two decades, various aspects of cardiopulmonary bypass and DHCA have been studied and modified such as optimisation of flows, anti-inflammatory interventions, haematocrit, and temperature to improve neurologic outcomes. With the changes in practice of DHCA, outcomes have significantly improved but SACP intuitively appears attractive to offer better neuroprotection. The strategy of conduct of SACP is evolving and needs to be standardised for comparing outcomes. In this review we have discussed the various physiological and technical factors involved in conduct of SACP in paediatric cardiac surgery and outcomes with SACP., Competing Interests: Conflict of interestsThe authors declare that they have no conflicts of interests., (© Indian Association of Cardiovascular-Thoracic Surgeons 2020.)

Small cell lung cancer, a subtype of lung cancer is an extremely malignant disease due to its metastases and recurrence. Patients with SCLC develop resistance to chemotherapy and the disease relapses. This relapse and resistance are attributed to the heterogeneity of SCLC. Various factors such as recurrent mutations in key regulatory genes such as TP53, RB1, and myc, epigenetic changes, and cancer stem cells contribute to the observed heterogeneity. Cancer stem cell models predict neuroendocrine origin of SCLC. Though an unambiguous established CSC marker has not been assigned, markers CD133, CD44 have been found associated with SCLC. Genetically engineered mouse models (GEMMs) allow the validation of driver mutations and are necessary for design of targeted therapy. This chapter outlines the factors contributing to SCLC heterogeneity, detection methods, and the current therapy trials.

Ethylene is a phytohormone that has gained importance through its role in stress tolerance and fruit ripening. In our study we evaluated the functional potential of the enzyme involved in ethylene biosynthesis of plants called ACC (aminocyclopropane-1-carboxylic acid) oxidase which converts precursor ACC to ethylene. Studies on ethylene have proven that it is effective in improving the flood tolerance in plants. Thus our goal was to understand the potential of ACC oxidase gene overexpression in providing flood tolerance in transgenic plants. ACC oxidase gene was PCR amplified and inserted into the pBINmgfp5-er vector, under the control of a constitutive Cauliflower Mosaic Virus promoter. GV101 strain of Agrobacterium tumefaciens containing recombinant pBINmgfp5-er vector (referred herein as pBIN-ACC) was used for plant transformation by the 'floral dip' method. The transformants were identified through kanamycin selection and grown till T3 (third transgenic) generation. The flood tolerance was assessed by placing both control and transgenic plants on deep plastic trays filled with tap water that covered the soil surface. Our result shows that wild-type Arabidopsis could not survive more than 20 days under flooding while the transgenic lines survived 35 days, suggesting development of flood tolerance with overexpression of ACC oxidase. Further molecular studies should be done to elucidate the role and pathways of ACC oxidase and other phytohormones involved in the development of flood adaptation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: In coarctation of aorta associated with proximal arch hypoplasia, extended end-to-end anastomosis through a thoracotomy would result in a residual gradient between the origins of the innominate and the left common carotid arteries. To eliminate this, we modified the surgical technique., Patients and Methods: Between March 2012 and May 2017, 50 patients (14 neonates) underwent repair of coarctation of aorta through a thoracotomy. The age ranged from 6 days to 2 years (median 2 months) and the weight from 1.8 to 8.0 kg (median 4.3 kg). A total of 15 patients (Group A) underwent repair by the extended end-to-end anastomosis. Among them, two patients developed early restenosis at the proximal arch requiring surgical reintervention. Hence, in the second half of the study, 35 patients (Group B) who were identified to have significant hypoplasia of the proximal arch underwent a modified end-to-side anastomosis of the descending aorta to the proximal arch incorporating the distal ascending aorta in the anastomosis and leaving the left subclavian artery end of the isthmus as an end-on vessel., Results: One neonate in Group B died due to a cause not related to the repair. All the other patients in Group B are doing well without a residual gradient during a median follow-up of 23 months. There were no airway issues related to extensive mobilization of the aorta., Conclusion: End-to-side anastomosis of the descending aorta to the proximal arch and side of the ascending aorta is possible through a thoracotomy and can be achieved with good outcome in neonates and infants., Competing Interests: There are no conflicts of interest.

Isolation of pure RNA is the basic requisite for most molecular biology work. Plants contain polyphenols and polysaccharides, which can interfere with isolation of pure RNA from them. Especially hardwood tree species like Paulownia elongata have surplus amount of RNA-binding alkaloids, proteins and secondary metabolites that can further complicate the process of RNA extraction. Paulownia elongata is a fast-growing tree species which is known for its role in environmental adaptability and biofuel research. Here we describe an economical, efficient and time-saving method (2 h) to extract RNA from leaf tissues of the tree Paulownia elongata . Lack of DNA contamination and good RNA integrity were confirmed using RNA Gel electrophoresis. The purity of RNA was confirmed using Nanodrop spectrophotometer that revealed an A 260 :A 280 ratio of about 2.0. The purified RNA was successfully used in the downstream applications such as RT-PCR (Reverse Transcription PCR) and qPCR (quantitative PCR). This method could be used for RNA extraction from several other recalcitrant tree species., (Copyright © 2018 The Authors; exclusive licensee Bio-protocol LLC.)

Cancer stem cells (CSCs) have gained an increasing attention recently in cancer research. CSCs have ability to generate new tumor through their stem cell properties, essentially self-renewal potential and differentiation into multiple cell lineages. Extensive evidences report that CSCs are resistant to many conventional therapies and mediate tumor recurrence. CSCs of lung cancer are well recognized by their specific markers such as CD133, CD44, ABCG2 and ALDH1A1 together with the CSC characteristics including spheroid and colony formation. Targeting these surface proteins with blocking antibodies and inhibition of ABC transporters and aldehyde dehydrogenase (ALDH) enzymes with small molecules may prove useful in inhibiting tumor progression. The Hh, Notch and Wnt pathways are key signaling cascades that govern cell fate during development and have been shown to be involved in CSCs in various solid tumors. Therapeutic approaches also target these signaling pathways in repressing the tumor progression. This review will focus on stem cell origins, role of signaling pathways, stem cell markers and therapeutic approaches specific to lung cancer., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.

Background: During repair of tetralogy of Fallot (TOF), when a transannular patch is needed in case of a small annulus and dysplastic pulmonary valve, we chose to reconstruct the right ventricular outflow tract by augmenting the divided anterior leaflet with an extracellular matrix (ECM) patch to produce a competent valve. In this study, we present our preliminary experience and early outcomes., Methods: From March 2013 to December 2015, of the 206 patients who underwent primary repair of TOF, 52 required a transannular incision. The median age was 18 months and the median weight was 8.2 kg. The native hinge mechanism of the valve was preserved by dividing only the anterior leaflet at the time of the transannular incision and augmenting it with an ECM patch that was sutured to the endocardium and to the divided leaflet., Results: Two patients died due to reasons not related to the use of the patch. Intraoperative evaluation showed a competent pulmonary valve without significant outflow gradient. During early follow-up (median 20 months), all patients were doing well without any decongestive therapy. Valve regurgitation was assessed as severe in 2, moderate in 26, and mild in 22 patients. In the majority of patients, the valve appeared thin and pliable in spite of mild to moderate regurgitation., Conclusions: Early experience with the use of ECM in repair of TOF shows satisfactory outcomes. It does not show obvious growth of the material. Long-term follow-up will be required in order to assess whether the valve function is durable without acquisition of significant regurgitation.

The bidirectional Glenn shunt operation is conventionally performed under cardiopulmonary bypass. Between June 2007 and September 2009, 218 consecutive patients underwent off-pump bidirectional Glenn shunt institution for single ventricle with pulmonary stenosis complex. Their mean age was 4.72 ± 1.80 years (range, 4 months to 6 years) and median weight was 10.12 kg (range, 4.1-19 kg). A temporary shunt was created between the innominate vein and the right atrium, with a 3-way connector for de-airing. Fifty-five patients had bilateral cavae. The mean internal jugular venous pressure on clamping the superior vena cava was 24.69 ± 1.81 mm Hg. Continuous end-tidal CO₂ and O₂ saturation were monitored. Adequate oxygen saturation and blood pressure were maintained by optimizing inotropics, volume, and inspired oxygen. The mean duration of ventilation was 10.17 ± 8.96 h (range, 1-73 h). There were no gross neurological complications. Postoperative pleural effusion developed in 6 (2.75%) patients, and 4 (1.83%) had nodal rhythm. Four (1.83%) patients died in the immediate postoperative period due to low cardiac output syndrome. Venoatrial shunt-assisted bidirectional Glenn shunt surgery can be performed safely by optimizing intraoperative management strategies. It is economical and avoids the deleterious effects cardiopulmonary bypass.

Central aorta-pulmonary artery shunts have fallen into disfavor because of shunt thrombosis and congestive heart failure, and a modified Blalock-Taussig shunt via thoracotomy can lead to pulmonary artery hypoplasia and distortion. We reviewed the outcomes of a modified Blalock-Taussig shunt by a sternotomy approach in 20 infants from July 2007 to October 2009. Their mean age was 5.79 months, and median weight was 5.4 kg. A 4-mm graft was placed in 11 patients, a 5-mm graft in 8, and a 3.5-mm graft in 1. There was no incidence of sepsis, seroma, or phrenic nerve palsy. There was one hospital death. The mean hospital stay was 10.4 +/- 4.3 days (range, 8-15 days). The mean oxygen saturation at discharge was 89% (range, 81%-93%). The sternotomy approach is technically easier to perform, cosmetically preferable, and probably hemodynamically superior. Correction of branch pulmonary stenosis is easily incorporated into this procedure. The theoretical disadvantage of this method is a potential technical difficulty with sternal reentry for subsequent procedures.

Objective: The bidirectional Glenn shunt is commonly performed under cardiopulmonary bypass for conditions that lead to a single ventricle repair. We report our experience of bidirectional Glenn shunt done without cardiopulmonary bypass., Methods: Between June 2007 and May 2009, 186 consecutive patients underwent off-pump bidirectional Glenn shunt for a variety of complex cyanotic congenital heart defects. Age ranged from four months to six years and the median weight was 11.17 kg (range 4.3 - 18). After systemic heparinization, the procedure was done by creating a temporary shunt between the innominate vein and the right atrium connected across a three way connector for de-airing. Fifty one patients had bilateral cavae. All cases underwent complete clinical neurological examination., Results: No case required conversion onto cardiopulmonary bypass. Four patients (2.14%) died in the immediate postoperative period. The mean internal jugular venous pressure on clamping the decompressed superior vena cava was 24.69 +/- 1.81 mm Hg. There was no intra-operative hemodynamic instability and oxygen saturation was maintained at more than 70% throughout. Post Glenn shunt, the saturations improved to mid 80s. Seventy four cases had documented forward flow across the pulmonary valve. The mean duration of ventilation was 10.17 +/- 8.96 hours and there were no neurological complications. Six patients (3.22%) developed pleural effusions, 4 patients (2.15%) had nodal rhythm and 9 patients (4.83%) had superficial sternal wound infection., Conclusions: Our results show that off-pump bidirectional Glenn shunt can be done safely in patients not requiring associated intra-cardiac correction. It avoids cardiopulmonary bypass and its related complications, is economical and associated with excellent results. In our opinion, this is the largest series of off-pump bidirectional Glenn shunt in the literature.