Maintainability of electronic instruments for meteorological applications

The concept of Maintainability (M) of electronic instruments. though of recent origin, has Important application for meteorological equipments, which have special requirements. M is defined quantitatively in terms of mean time to repair and is Influenced by the failure behaviour of an equipment. An equipment goes through teething trouble, useful and terminal phase. Much of maintainability can be incorporated during design and production phase. This reduces the effective overall cost of the equipment during its life time. Special maintenance support system is necessary for meteorological Instruments. Some recent tools for trouble shooting in digital systems have been discussed.

Limited allele-specific gene expression in highly polyploid sugarcane

Polyploidy is widespread in plants allowing the different copies of genes to be expressed differently in a tissue specific or developmental specific way. This allele-specific expression (ASE) has been widely reported but the proportion and nature of genes showing this characteristic have not been well defined. We now report an analysis of the frequency and patterns of ASE at the whole genome level in the highly polyploid sugarcane genome. Very high-depth whole genome sequencing and RNA sequencing revealed strong correlations between allelic proportions in the genome and in expressed sequences. This level of sequencing allowed discrimination of each of the possible allele doses in this 12-ploid genome. Most genes were expressed in direct proportion to the frequency of the allele in the genome with examples of polymorphisms being found with every possible discrete level of dose from 1:11 for single copy alleles to 12:0 for monomorphic sites. The rarer cases of ASE were more frequent in the expression of defense-response genes, as well as in some processes related to the biosynthesis of cell walls. ASE was more common in genes with variants that resulted in significant disruption of function. The low level of ASE may reflect the recent origin of polyploid hybrid sugarcane. Much of the ASE present can be attributed to strong selection for resistance to diseases in both nature and domestication.

Emergence and radiation of distemper viruses in terrestrial and marine mammals

Canine distemper virus (CDV) and phocine distemper virus (PDV) are major pathogens to terrestrial and marine mammals. Yet little is known about the timing and geographical origin of distemper viruses and to what extent it was influenced by environmental change and human activities. To address this, we (i) performed the first comprehensive time-calibrated phylogenetic analysis of the two distemper viruses, (ii) mapped distemper antibody and virus detection data from marine mammals collected between 1972 and 2018, and (iii) compiled historical reports on distemper dating back to the eighteenth century. We find that CDV and PDV diverged in the early seventeenth century. Modern CDV strains last shared a common ancestor in the nineteenth century with a marked radiation during the 1930s–1950s. Modern PDV strains are of more recent origin, diverging in the 1970s–1980s. Based on the compiled information on distemper distribution, the diverse host range of CDV and basal phylogenetic placement of terrestrial morbilliviruses, we hypothesize a terrestrial CDV-like ancestor giving rise to PDV in the North Atlantic. Moreover, given the estimated timing of distemper origin and radiation, we hypothesize a prominent role of environmental change such as the Little Ice Age, and human activities like globalization and war in distemper virus evolution.

A bipartite chromatophore transit peptide and N-terminal processing of protein in the Paulinella chromatophore

The cercozoan amoeba Paulinella chromatophora contains photosynthetic organelles - termed chromatophores - that evolved from a cyanobacterium ~100 million years ago, independently from plastids in plants and algae. Despite its more recent origin, at least one third of the chromatophore proteome consists of nucleus-encoded proteins that are imported by an unknown mechanism across the chromatophore double envelope membranes. Chromatophore-targeted proteins fall into two classes. Proteins exceeding 250 amino acids carry a conserved N-terminal sequence extension, termed the 'chromatophore transit peptide' (crTP), that is presumably involved in guiding these proteins into the chromatophore. Short imported proteins do not carry discernable targeting signals. To explore whether the import of protein is accompanied by their N-terminal processing, here we used a mass spectrometry-based approach to determine protein N-termini in Paulinella chromatophora and identified N-termini of 208 chromatophore-localized proteins. Our study revealed extensive N-terminal modifications by acetylation and proteolytic processing in both, the nucleus and chromatophore-encoded fraction of the chromatophore proteome. Mature N-termini of 37 crTP-carrying proteins were identified, of which 30 were cleaved in a common processing region. Our results imply that the crTP mediates trafficking through the Golgi, is bipartite and surprisingly only the N-terminal third ('part 1') becomes cleaved upon import, whereas the rest ('part 2') remains at the mature proteins. In contrast, short imported proteins remain largely unprocessed. Finally, this work sheds light on N-terminal processing of proteins encoded in an evolutionary-early-stage photosynthetic organelle and suggests host-derived post-translationally acting factors involved in dynamic regulation of the chromatophore-encoded chromatophore proteome.

Saturn’s Rings

Saturn’s rings are not only a beautiful and enduring symbol of space, but astronomers’ best local laboratory for studying phenomena in thin cosmic disks like those where planets formed. All the giant planets have ring systems. Saturn’s are the biggest and brightest. Saturn’s rings are made of innumerable icy particles, ranging from the size of dust to that of football stadiums. Galileo discovered Saturn’s rings with his newly invented telescope, but they were not explained until Huygens described them as thin, flat disks surrounding the planet. In the space age, rings were found around the other giant planets in our solar system. Rings have been seen around asteroids and likely exist around exoplanets. Many of the ring structures seen are created by gravity from Saturn’s moons. Rings show both ongoing aggregation and disaggregation. After decades of study from space and by theoretical analysis, some puzzles still remain unexplained. There is evidence for youthful rings from Cassini results, but no good theory to explain their recent origin. A future Saturn Ring Observer mission would be able to determine the direct connections between the individual ring physical properties and the origin and evolution of larger structures.

Evolution of Root Morphology in Table Beet: Historical and Iconographic

The Beta vulgaris complex includes sugar beet, mangel wurzel, Swiss chard, fodder beet, and table beet. Mangel wurzel and fodder beet are considered to be the same general crop type, with the former possessing lower dry matter content (<13%) than the latter. Mangel is likely derived from crosses between table beet and chard, while fodder beet may have a more recent origin, arising from crosses between mangel and sugarbeet. The table beet was derived from the wild sea beet, B. vulgaris (L.) subsp. maritima (L.) Arcang, with small non-spherical roots. Table beet is presently a popular vegetable cultivated for its pigmented roots, typically red but also yellow and other colors. Wild forms were consumed in antiquity mainly for their leaves with roots used medicinally. Beet is referred to in the Septuagint, a Greek translation of the first five books of the Hebrew bible, made in Ptolomeic Egypt in the third century BCE. A beet identified as Beta maritima is included in De Material Medicus of Pedanius Dioscorides written in the first century CE, and the first illustrated version of 512, known as the Juliana Anicia Codex, includes an image with non-spherical root. Beet is mentioned in several tractates of the Talmud, a sixth century collection of history and civil law written in Babylonia. Beta maritima possesses supernumerary root cambia, which facilitated selection of swollen rooted forms. The first colored illustration of swollen rooted table beet, B. vulgaris, can be found in the 1515–1517 frescos of Raphael Sanzio and Giovanni Martina da Udine in the Villa Farnesina in Rome. Swollen roots in Roman beet are illustrated and described in the 1587 French herbal Historia Generalis Plantarum of Jacques Dalechamps. Conically shaped beet roots are found in the market painting of Franz Snijders in the 17th century. Various spherical forms of beet root are found in the work of American painter James Peale in 1826. A complete array of beet root types is found in the Benary catalog of 1876. Modern, spherical beet roots were depicted in 1936 by the Russian painter Zinaida Serebriankov, 1936. Artistic and historical representations of table beet suggest that swollen rooted forms have existed during the past five centuries, but conically shaped roots were gradually replaced by spherically shaped roots during this period.

Exploring the Origins of Bhutan’s Gross National Happiness

Bhutan’s Gross National Happiness (GNH) is often dismissed by its critics as being an instrument for policy elites to address ‘national security concerns’ that started to threaten their grasp on the state around the turn of the millennium. This study problematizes this line of criticism that relegates GNH to an ‘invented tradition’ of recent origin. For this purpose, this study draws on Roy Wagner’s notion of ‘invention’ that draws attention to how various sets of meanings are brought together. A historical analysis of the country’s development plans points to several origins of GNH, including ‘Buddhism and Bhutan’s traditional socio-economic system’ and ‘outside concepts’ holding sway in international debates on development. GNH has undergone a long and gradual process of elaboration in view of Buddhist mores and development discourses, while also taking into account national security concerns. This study concludes by warning against the reductionistic stance of GNH critics, in favour of a more balanced perspective that captures the multiplicity of the origins of GNH.

Telomere-to-telomere assembly of a fish Y chromosome reveals the origin of a young sex chromosome pair

Background The origin of sex chromosomes requires the establishment of recombination suppression between the proto-sex chromosomes. In many fish species, the sex chromosome pair is homomorphic with a recent origin, providing species for studying how and why recombination suppression evolved in the initial stages of sex chromosome differentiation, but this requires accurate sequence assembly of the X and Y (or Z and W) chromosomes, which may be difficult if they are recently diverged. Results Here we produce a haplotype-resolved genome assembly of zig-zag eel (Mastacembelus armatus), an aquaculture fish, at the chromosomal scale. The diploid assembly is nearly gap-free, and in most chromosomes, we resolve the centromeric and subtelomeric heterochromatic sequences. In particular, the Y chromosome, including its highly repetitive short arm, has zero gaps. Using resequencing data, we identify a ~7 Mb fully sex-linked region (SLR), spanning the sex chromosome centromere and almost entirely embedded in the pericentromeric heterochromatin. The SLRs on the X and Y chromosomes are almost identical in sequence and gene content, but both are repetitive and heterochromatic, consistent with zero or low recombination. We further identify an HMG-domain containing gene HMGN6 in the SLR as a candidate sex-determining gene that is expressed at the onset of testis development. Conclusions Our study supports the idea that preexisting regions of low recombination, such as pericentromeric regions, can give rise to SLR in the absence of structural variations between the proto-sex chromosomes.

Phylogeny of Anisepyris Kieffer (Hymenoptera: Bethylidae: E pyrinae), with investigation of diagnostic features

A cladistic analysis based on 120 morphological characters and 72 OTUs was conducted for the flat wasp genus Anisepyris Kieffer. The genus is mainly Neotropical region with few Nearctic species. The analysis retrieved well-supported relationships among the Anisepyris species and exposed the distribution of synapomorphies among the lineages, particularly concerning the mandible shape, dorsal pronotal area sulcus, and mesopleural foveae. The main diagnostic characters, described by Barbosa and Azevedo (2018) for the 13 species-groups of Anisepyris, were scrutinized. Transformation series and evolutionary hypotheses were also discussed. This discussion elucidates the importance of each character in the evolution and diversification along the different lineages. A discussion on the species-groups distribution is proposed, in relation to their diagnostic features. A hypothesis about the original distribution and the subsequent diversifications was also discussed. In conclusion, due to a possible recent origin for Anisepyris species, the dispersion could be related primarily to dense forest areas; and the retrieved synapomorphies could be related to posterior distributions of the species in disparate areas from their original environment.

Limited allele-specific gene expression in highly polyploid sugarcane

Polyploidy is widespread in plants allowing the different copies of genes to be expressed differently in a tissue specific or developmental specific way. This allele specific expression (ASE) has been widely reported but the proportion and nature of genes showing this characteristic has not been well defined. We now report an analysis of the frequency and patterns of ASE at the whole genome level in the highly polyploid sugarcane genome. Very high-depth whole genome sequencing and RNA-sequencing revealed strong correlations between allelic proportions in the genome and in expressed sequences. This level of sequencing allowed discrimination of each of the possible allele doses in this 12-ploid genome. Most genes were expressed in direct proportion to the frequency of the allele in the genome with examples of polymorphisms being found with every possible discrete level of dose from 1:11 for single copy alleles to 12:0 for monomorphic sites. The rarer departures from allelic balance were more frequent in the expression of defence-response genes, as well as in some processes related to the biosynthesis of cell walls. ASE was more common in genes with variants that resulted in significant disruption of function. The low level of ASE may reflect the recent origin of polyploid hybrid sugarcane. Much of the ASE present can be attributed to strong selection in nature and domestication for resistance to diseases.