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Supersonic intakes, under adverse operating conditions, can have unwanted oscillations of shock system internal and external to its duct, known as intake buzz. These buzz instabilities degrade intake performance by causing violent pressure fluctuations, reducing mass flow, decreasing thrust, and leading to combustion instabilities as well. This study examines the onset of this buzz in an axisymmetric intake with various throttles and investigates the effects of dynamic angular deflection of a portion of the cowl on the resulting buzz phenomena. Computations and experiments were conducted at Mach number of 2.0 to obtain the buzz in an axisymmetric intake and investigate its behaviour under various throttle conditions. Dailey-type buzz is observed to be predominant for the present axisymmetric intake, and it has been also quantified that the time period of oscillations for higher throttling ratios is not constant. A technique of dynamically varying the portion of the cowl tip about a pivot point was attempted here to eliminate the intake buzz during onset as well as during a complete buzz cycle. It has been found that the current technique is useful in seizing the buzz shock expulsion from the intake duct, hence restricting unstart and further adversities.
Rice crop is affected by different types of floods at different stages of the crop cycle. Constant efforts of researchers resulted in the development of rice varieties for anaerobic germination, flash floods and stagnant flooding by both conventional and molecular breeding approaches. Detection of QTLs for different types of floods in new genetic source (AC39416A) is needed to combat adverse effects of climate change. Present investigation was carried out to identify QTLs for flood tolerance using recombinant inbred lines derived from Indra and AC39416A. QTL mapping resulted in identification of QTLs, qAG3.1 on chromosome 3 for anaerobic germination and qSF10.1 on chromosome 10 for plant survival % under stagnant flooding. These QTLs explain 59.08 and 13.21% of phenotypic variance respectively. Two candidate genes were identified in qAG3.1 region, LOC_Os03g42130 gibberellin 20 oxidase2 and LOC_Os03g44170 glutathione S-transferase. The underlying mechanism might be the inhibition of gibberellic acid synthesis and thereby protecting seedlings from oxidative stress under anoxia condition. Genomic region of qSF10.1 revealed LOC_Os10g35020 glycosyltransferase and LOC_Os10g35050 aquaporin protein loci, which might be responsible for adaptive mechanism for plant survival % under stagnant flooding. This indicates that the new genetic resource AC39416A has an ability to adopt to different types of flood tolerance in response to environmental stress. Unveiling physiological and molecular mechanisms for flood tolerance in AC39416A using advanced omics studies would help in precise genomic selections for sustained production in flood-prone areas.
Beachpea (Vigna marina) is a halophytic wild leguminous plant which occurs throughout tropical and subtropical beaches of world. As quantitative trait loci (QTLs) for salt tolerance in V. marina and its crossability with other Vigna species are known, the current study was undertaken to know the presence of these QTLs in the V. marina accessions along with check varieties of pulses. Accordingly, 20 Vigna genotypes (15 accessions of V. marina collected from sea-shore areas of Andaman and Nicobar Islands along with five check varieties of green gram and black gram) were subjected to molecular characterization using seven simple sequence repeat (SSR) markers associated with salt tolerance. Of the markers used, only four SSR markers amplified in the studied germplasm. Number of alleles detected per primer and size of alleles ranged from 1 to 3 and 100 to 325 bp, respectively. Polymorphism information content and heterozygosity values ranged from 0.305 to 0.537 and 0.375 to 0.612, respectively. Three major clusters, cluster I, II and III were obtained at Jaccard's similarity coefficient value of 0.48 through the un-weighted paired group method with arithmetic means method of cluster analysis. It grouped green gram and black gram genotypes in clusters I (04) and II (01), whereas all V. marina genotypes were grouped in cluster III (15). Principal co-ordinate analysis explained 85.9% of genetic variation among genotypes which was further confirmed by cluster analysis. This study indicated the effectiveness of SSR markers in separating cultivated Vigna species from wild V. marina. The findings will be useful for transferring trait of robust salt tolerance of V. marina in cultivated Vigna species using marker-assisted breeding.
Case fatality rate (CFR) and doubling time are important characteristics of any epidemic. For coronavirus disease 2019 (COVID-19), wide variations in the CFR and doubling time have been noted among various countries. Early in the epidemic, CFR calculations involving all patients as denominator do not account for the hospitalised patients who are ill and will die in the future. Hence, we calculated cumulative CFR (cCFR) using only patients whose final clinical outcomes were known at a certain time point. We also estimated the daily average doubling time. Calculating CFR using this method leads to temporal stability in the fatality rates, the cCFR stabilises at different values for different countries. The possible reasons for this are an improved outcome rate by the end of the epidemic and a wider testing strategy. The United States, France, Turkey and China had high cCFR at the start due to low outcome rate. By 22 April, Germany, China and South Korea had a low cCFR. China and South Korea controlled the epidemic and achieved high doubling times. The doubling time in Russia did not cross 10 days during the study period.
Surgery for CHD has been slow to develop in parts of the former Soviet Union. The impact of an 8-year surgical assistance programme between an emerging centre and a multi-disciplinary international team that comprised healthcare professionals from developed cardiac programmes is analysed and presented.
Material and methods
The international paediatric assistance programme included five main components – intermittent clinical visits to the site annually, medical education, biomedical engineering support, nurse empowerment, and team-based practice development. Data were analysed from visiting teams and local databases before and since commencement of assistance in 2007 (era A: 2000–2007; era B: 2008–2015). The following variables were compared between periods: annual case volume, operative mortality, case complexity based on Risk Adjustment for Congenital Heart Surgery (RACHS-1), and RACHS-adjusted standardised mortality ratio.
Results
A total of 154 RACHS-classifiable operations were performed during era A, with a mean annual case volume by local surgeons of 19.3 at 95% confidence interval 14.3–24.2, with an operative mortality of 4.6% and a standardised mortality ratio of 2.1. In era B, surgical volume increased to a mean of 103.1 annual cases (95% confidence interval 69.1–137.2, p<0.0001). There was a non-significant (p=0.84) increase in operative mortality (5.7%), but a decrease in standardised mortality ratio (1.2) owing to an increase in case complexity. In era B, the proportion of local surgeon-led surgeries during visits from the international team increased from 0% (0/27) in 2008 to 98% (58/59) in the final year of analysis.
Conclusions
The model of assistance described in this report led to improved adjusted mortality, increased case volume, complexity, and independent operating skills.
TiO2 has been widely studied as a photocatalytic material due to its non-toxicity, chemical inertness, and high photocatalytic activity. Here, we explore the operational behavior of a novel TiO2 micropillars array being developed to use solar radiation to treat recycled wastewater in long-duration space missions. A Light Capture model was developed to model light absorption. The Lattice Boltzmann method was used to simulate water flow, and the finite element method was used to model waste mass transfer.
Association mapping (AM), an alternative method of quantitative trait loci (QTL) discovery, exploits historic linkage disequilibrium (LD) present in natural populations. AM is effective in self-pollinated crops such as Dolichos bean as LD extends over longer genomic distance driven-by low rate of recombination and thereby requiring fewer markers for exploring marker-traits associations. A core set of Dolichos bean germplasm consisting of 64 accessions was evaluated for nine quantitative traits (QTs) during 2014 and 2015 rainy seasons and genotyped using 234 simple sequence repeats (SSR) markers. Substantial diversity was observed among the core set accessions at loci controlling QTs and 95 of the 234 SSR markers were found polymorphic. The structure analysis and low magnitude of fixation indices suggested weak population structure, which in-turn indicated the low possibility of false discovery rates in the marker-QTs association. The marker allele's scores were regressed onto phenotypes at nine QTs following general linear model and mixed linear model for exploring marker-QTs associations. Significantly higher number of SSR markers was found associated with genomic regions controlling nine QTs. A few of the markers such as KT Dolichos (KTD) 200 for days to 50% flowering, KTD 273 for fresh pod yield per plant and KTD 130 for fresh pods per plant explained ≥10% of the trait variations. The study could also identify a few SSR markers such as KTD 273, KTD 271 and KTD 130 linked to multiple traits. These linked SSR markers are suggested for validation for their use in marker-assisted Dolichos bean improvement programmes.
Olivines from igneous rocks generally have low calcium contents. However, olivines crystallized from strongly silica-undersaturated magmas occasionally contain large amounts of kirschsteinite (Ki" CaFeSiO4) and monticellite (Mo: CaMgSiO4) components. The purpose of this note is to report the first natural occurrence of kirschsteinite crystals that have lamite (La: CazSiO4) in the mineralogical norm.
This study was conducted to characterize new plant type (NPT) traits among 650 genetically diverse rice genotypes of tropical japonica and indica and to establish an initial core set for NPT traits. Analysis of variance revealed highly significant differences among the genotypes for all the traits assessed except flag length and width and leaf angles. Dendrogram categorized the genotypes into five distinct duration groups. Genotypes viz., Pumphamah, IRGC5097, IRGC37015, IRGC43741, IRGC50448, IRGC53089, IRGC39111, IRGC18021, Haorei Machang, IRGC44069, IRGC8269, Thangmoi, IRGC33130 and IRGC29772 were identified as possessing strong culm. Long panicles with a length of more than 35 cm were found in IRGC8269, IRGC9147, IRGC14694, IRGC19642, IRGC27435, IRGC39111, IRGC31051, IRGC26011and IRGC25892. Ideal leaf angle of NPT genotypes of 5°, 10° and 20° of flag leaf, 1st and 2nd leaves was not found in any genotype but with a combination of 5°, 10° and 10° was observed in IRGC63102 and IRGC66644. NPT flag leaf length and width of 50 and 2 cm, respectively, was seen in ‘Kemenya Kepeu’ and ‘IRGC29772’. High grain number of more than 350 was observed in IRGC53089, IRGC31063 and Azhoghi. A total of 72 genotypes were found with a combination of one or more ideal plant type traits of which, hierarchical cluster analysis based on genetic distances selected 32 as NPT core set. This core set will serve as an ideal genetic resource for breeding programs aimed at NPT development.
The theory of non-stationary motion around aerofoils has many important applications in the field of aeronautics and turbomachines. The most significant problems are flutter, fluctuating loads experienced by blades of a typical turbomachine which move through a non-uniform field of flow, disturbed by the induced effects of other stationary and moving blade rows. It is important to predict the fluctuating lift force on a blade or aerofoil due to a flow disturbance, because both the blade vibration and noise generation are related to fluctuating lift and moment.
This paper discusses the evolution of airpower and the ever-increasing component of stealth technology in dictating warfare, based on the need felt in the literature to integrate and place them in the right perspective. Hence, the role of stealth aircraft and the dominance of all aspects of stealth technology, especially in recent conflicts, are reviewed. The integration of the fundamental aspects of stealth technology, through its classification, types of aircraft signatures: especially radar, infrared, and visual signatures, their sources of origin, modelling techniques, and methods of signature reduction are discussed. Due to the increasing importance of infrared signatures relative to radar signatures, infrared signatures are also closely examined and analysed. Hence, the lock-on and surveillance ranges of infrared detectors are compared. Future projections in stealth technology, especially based on the role of anti-stealth technologies, are also elaborated.
This study reports a novel class of biodegradable polyurethane biomaterials and three-dimensional scaffolds for tissue engineering. Solvent casted polyurethane films were studied for biocompatibility by seeding with human bone marrow derived stromal cells. In order to develop a three-dimensional and porous structure, a dynamic solvent sintering method was applied to the polyurethanes for the first time. Microstructural studies on the sintered scaffolds reveal porous structure formation with bonding between the adjacent microspheres. In conclusion, this study establishes new polyurethane biomaterials that are fully absorbable for tissue engineering applications.
Fruit flies (Diptera: Tephritidae) are major pests worldwide. The sterile insect technique, where millions of flies are reared, sterilized by irradiation and then released, is one of the most successful and ecologically friendly methods of controlling populations of these pests. The mating behaviour of irradiated and non-irradiated flies has been compared in earlier studies, but there has been little attention paid to the anti-predator behaviour of mass-reared flies, especially with respect to wild flies. Tephritid flies perform a supination display to their jumping spider predators in order to deter attacks. In this study, we evaluated the possibility of using this display to determine the anti-predator capabilities of mass-reared irradiated, non-irradiated flies, and wild flies. We used an arena setup and observed bouts between jumping spiders (Phidippus audax Hentz) and male Mexican fruit flies (Anastrepha ludens Loew). We show that although all flies performed a supination display to their predator, wild flies were more likely to perform a display and were significantly more successful in avoiding attack than mass-reared flies. We suggest that this interaction can be used to develop a rapid realistic method of quality control in evaluating anti-predator abilities of mass-reared fruit flies.
The protein-rich non-conventional detoxified karanja cake (dKC) can be used in place of conventional protein supplements like soybean meal (SBM), groundnut meal, etc. in livestock feed. The present study was conducted to assess the effect of two levels of dKC by replacing SBM on testicular architecture, semen quality and expressions of mRNAs encoding luteinizing hormone receptor (LHR) and insulin-like growth factor (IGF-I) in testes of ram lambs. Eighteen ram lambs were randomly divided into three groups (n = 6) and fed different levels (%) of karanja cake (0% replacement – control; 50% replacement – dKC-50 and 75% replacement – dKC-75) for 140 days. After 120 days of feeding, the semen from the animals was collected and analysed. The testes samples were collected on day 140 of feeding for transcripts expression studies. The dKC-50 group had no change in BW, whereas dKC-75 group showed decreased (P < 0.05) BW as compared with control. The number of animals ejaculated semen in dKC-75 group was lower (P < 0.05) than the control group. A reduction (P < 0.05) in LHR expression in dKC-75 was observed, whereas a reduction in IGF-I expression (P < 0.05) was observed in dKC-50 and dKC-75 as compared with control group. The study reveals that in ram lambs, long-term feeding of dKC at 50% replacement of SBM may not affect BW. However, long-term feeding of dKC as a replacement of SBM may affect testicular function.
The cultivar Ajaya (IET 8585) exhibits durable broad-spectrum resistance to bacterial blight (BB) disease of rice and is widely used as a resistance donor. The present study was carried out to decipher the genetics of BB resistance in Ajaya and map the gene(s) conferring resistance. Genetic analysis in the F2 indicated a quantitative/additive nature of resistance governed by two loci with equal effects. Linked marker analysis and allelic tests revealed that one of the resistance genes is xa5. Sequence analysis of a 244 bp region of the second exon of the gene-encoding Transcription factor IIAγ (the candidate gene for xa5) confirmed the presence of xa5. Bulked-segregant analysis (BSA) revealed the putative location of the two quantitative trait loci (QTLs)/genes associated with resistance on chromosomes 5 and 8. Composite interval mapping located the first locus on Chr. 5S exactly in the genomic region spanned by xa5 and the second locus (qtl BBR 8.1) on Chr. 8L. Owing to its differential disease reaction with a set of seven hyper-virulent isolates of Xanthomonas oryzae, a map location on Chr. 8L, which was distinct from xa13 and data from allelism tests, the second resistance locus in Ajaya was determined to be novel and was designated as xaAj. A contig map spanning xaAj was constructed in silico and the genomic region was delimited to a 13·5 kb physical interval. In silico analysis of the genomic region spanning xaAj identified four putatively expressed candidate genes, one of which could be involved in imparting BB resistance in Ajaya along with xa5.