Petrology and geochemistry of Proterozoic olivine tholeiite intrusives from the Central Crystallines of the Western Arunachal Himalaya, India: evidence for a depleted mantle

A number of plugs and dykes of mafic rocks are encountered between Se La and Jung areas of the Central Crystalline rocks of western Arunanchal Himalaya. These mafic intrusives are emplaced within the Paleoproterozoic high to medium grade schists and gneisses of Se La Group. These mafic reeks are Dietamorphosed and composed of hornblende (~70%) and plagioclase showing granoblastic texture. Geo-chemically they show olivine tholeiitic characteristics. Appreciable amount of normative hypersthene and olivine is present in all samples. The geochemistry of high-field strength (+ rare-earth) elements suggests that these mafic rocks are co-genetic and derived from olivine tholeiite melt generated from a depleted lher-zolite mantle source. These mafic rocks show very close geochemical similarities with mafic rocks reported from the western Himalaya. The satellite imageries suggest that these mafic intrusive rocks are exposed at intersection of major lineaments. The asso­ciation of these mafic rocks with major lineaments, mostly fault planes, advocates that these originally deep seated intrusions have been upthrown and exposed along the fault planes

History, epidemiology and regional diversities of urolithiasis

Archeological findings give profound evidence that humans have suffered from kidney and bladder stones for centuries. Bladder stones were more prevalent during older ages, but kidney stones became more prevalent during the past 100 years, at least in the more developed countries. Also, treatment options and conservative measures, as well as ‘surgical’ interventions have also been known for a long time. Our current preventive measures are definitively comparable to those of our predecessors. Stone removal, first lithotomy for bladder stones, followed by transurethral methods, was definitively painful and had severe side effects. Then, as now, the incidence of urolithiasis in a given population was dependent on the geographic area, racial distribution, socio-economic status and dietary habits. Changes in the latter factors during the past decades have affected the incidence and also the site and chemical composition of calculi, with calcium oxalate stones being now the most prevalent. Major differences in frequency of other constituents, particularly uric acid and struvite, reflect eating habits and infection risk factors specific to certain populations. Extensive epidemiological observations have emphasized the importance of nutritional factors in the pathogenesis of urolithiasis, and specific dietary advice is, nowadays, often the most appropriate for prevention and treatment of urolithiasis

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Structural analyses of the crystalline rocks between Dirang and Tawang, West Kameng district, Arunachal Himalaya

In Kameng Valley of Arunachal Pradesh, the crystalline rocks of Se La Group of Higher Himalaya are thrust over the Lesser Himalayan rocks of Dirang Formation, Bomdila Group along the Main Central Thrust and exhibit well preserved structures on macro- to microscopic scales. Detailed analysis of structures reveals that the rocks of the area have suffered four phases of deformation D1, D2, D3 and D4. These structures have been grouped into (i) early structures (ii) structures related to progressive ductile thrusting and (iii) late structures. The early structures which developed before thrusting formed during D1 and D2 phases of deformation, synchronous to F1 and F2 phases of folding respectively. The structures related to progressive ductile shearing developed during D3 phase of deformation, when the emplacement of the crystalline rocks took place over the rocks of Dirang Formation along the Main Central Thrust. Different asymmetric structures/kinematic indicators developed during this ductile/brittle-ductile regime suggest top-to-SSW sense of movement of the crystalline rocks of the area. D4 is attributed to brittle deformation. Based on satellite data two new thrusts, i.e. Tawang and Se La thrusts have been identified parallel to Main Central Thrust, which are suggestive of imbricate thrusting. Strain analysis from the quartz grains of the gneissic rocks reveals constriction type of strain ellipsoid where k value is higher near the MCT, gradually decreases towards the north. Further, the dynamic analysis carried out on the mesoscopic ductile and brittle-ductile shear zones suggest a NNE-SSW horizontal compression corresponding to the direction of northward movement of Indian Plate

Palaeoproterozoic rift-related alkaline magmatism in Bari area, Son valley, Central India

Earlier studies on Palaeoproterozoic (∼1800 Ma) alkaline (shoshonitic) rocks comprised of limited petrochemical data on the Bari syenite and other contiguous felsic rocks emplaced in anorogenic rift setting along the Son-Narmada North Fault (SNNF). Using new major and trace element data-sets, this study offers means of study of origin, source of magma, tectonic settings and geodynamic implications. The major oxide chemistry grouped Bari rocks into high alkali, but low CaO bearing peraluminous alkaline rocks. These rocks represent high abundance of HREE, Zr, Nb, Ga, Y, Eu, Ba and Sr. Primitive mantle normalized REE and trace elemental patterns correspond to A-type suite, suggesting origin of the magma mainly from the mantle. Significantly, anomalous Th/U and Rb/Cs values revealed crustal contamination of the melt, derived from partial melting of the mantle. Moreover, binary data plots between La vs. La/Sm and La vs. La/Yb are pointing towards crustal assimilation which was concomitant with the fractional crystallization of the mantle derived melt. Thus, crustal contamination coupled with the fractional crystallization of the melt mainly contributed to the formation of syenite melt. But, a high degree of partial melting of the lower crust was primarily responsible for the formation of Bari granite. The enrichment of incompatible elements in the syenite rocks suggests involvement of mantle metasomatism in their genesis. The magmatic processes related to the formation of syenite, lamprophyre, ultramafics, mafic and granite bodies were operative in the diverse magmatic realm and initiated earlier at the waning stage of the Mahakoshal orogeny and continental rifting, but magma emplaced later during Post-Mahakoshal orogeny and Pre-Vindhyan sedimentation that also in a rifted basement of the Bundelkhand craton at ∼1800 Ma during the amalgamation of the Columbian Supercontinent

Not Available

Not AvailableThe relationship between length and weight of three fish species Johnius coitor (Family Sciaenidae), Osteobrama cotio (Family Cyprinidae) and Gonialosa manmina (Family Clupeidae) unknown to Fishbase were studied from the Allahabad waters of the river Ganga in India. Fishes were captured bi‐monthly from March 2017 to June 2018 using gill nets and cast nets of various mesh sizes. The b values determined from length weight relationships (LWRs) were 3.246, 3.373 and 3.024 for J. coitor, O. cotio and G. manmina, respectively.NMC