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The present study describes and illustrates six bivalve taxa from the Early Bathonian to Early Callovian Ferruginous Oolite Formation and 24 taxa from the Callovian to basal-most Cretaceous Spiti Shale Formation of the Spiti and Zanskar areas in the Indian Himalayas. The Spiti Shale Formation contains a low-diversity bivalve fauna that is concentrated in few horizons, particularly in the lower member of the formation. With few exceptions, the bivalves are poorly preserved. Bivalve taxa recorded by earlier studies are revised wherever possible. Several of the taxa, most of which are from mid- to outer shelf environments, are characteristic of the south-eastern margin of the Neotethys, but some are also closely related to forms occurring in Kachchh, a rift basin situated at the western margin of the Indian Craton.

A Hildoglochiceras-rich horizon is reported from a thin carbonate intercalation within the siliciclastic Upper Jurassic Jhuran Formation of the Jara Dome, western Kachchh Mainland. The Hildoglochiceras specimens have been used for the first population-level study of the genus based on a multivariate analysis. High phenotype instability in the large sample confirms the occurrence of transient forms between morphospecies. Key morphological traits for interpreting Hildoglochiceras are stated, and the morphospecies Hildoglochiceras kobelli (Oppel) and H. kobelliforme (Bonarelli) are interpreted as a dimorphic pair. The ammonite-rich level is interpreted as a Hildoglochiceras Horizon, which is related to a transgressive pulse and maximum flooding zone interrupting largely restrictive conditions for ammonites. The endemic character of Hildoglochiceras is confirmed and related to its environmental restriction to shelf areas on the palaeomargins of the Trans-Erythraean Trough. A comprehensive review of biostratigraphic interpretations of Hildoglochiceras shows the influence of natural and experimental forcing factors. The uppermost Kimmeridgian to lowermost Upper Tithonian interval is the widest biostratigraphic range assumable for Hildoglochiceras based on existing reports, but most probably it was restricted to, or at least better represented in, Lower Tithonian horizons. The Hildoglochiceras Horizon described here is correlated with a lower part of the Albertinum/Darwini Zone in the Secondary Standard Scale for ammonite-based bio-chronostratigraphy in European and West-Tethyan areas. According to the current state of knowledge, a local rather than wide regional significance is favoured for Hildoglochiceras records before its significance for precise correlation across the Trans-Erythraean Trough.

Recent preclinical trials have shown that alginate injections are a promising treatment for ischemic heart disease. Although improvements in heart function and global structure have been reported following alginate implants, the underlying structure is poorly understood. Using high resolution ex vivo MRI and DT-MRI of the hearts of normal control swine (n = 8), swine with induced heart failure (n = 5), and swine with heart failure and alginate injection treatment (n = 6), we visualized and quantified the fibre distribution and implant material geometry. Our findings show that the alginate injectates form solid ellipsoids with a retention rate of 68.7% ± 21.3% (mean ± SD) and a sphericity index of 0.37 ± 0.03. These ellipsoidal shapes solidified predominantly at the mid-wall position with an inclination of -4.9° ± 31.4° relative to the local circumferential direction. Overall, the change to left ventricular wall thickness and myofiber orientation was minor and was associated with heart failure and not the presence of injectates. These results show that alginate injectates conform to the pre-existing tissue structure, likely expanding along directions of least resistance as mass is added to the injection sites. The alginate displaces the myocardial tissue predominantly in the longitudinal direction, causing minimal disruption to the surrounding myofiber orientations.

Abstract The stable isotope (δ13C, δ18O) composition of a collection of Lower Jurassic brachiopods and oysters from the Andean Basin of northern Chile was analyzed. The results allow the first reconstruction of absolute water temperatures for several ammonite zones in the Lower Jurassic of South America. The temperature record starts with comparatively high values in the Late Sinemurian (average: 27.0 °C; Raricostatum Zone). Just before the Sinemurian–Pliensbachian transition, temperatures dropped to an average of 24.3 °C. The lowest temperature value in the dataset was recorded for a brachiopod shell of the latest Pliensbachian Spinatum Zone (19.6 °C). No data are available for the Early Toarcian, but results for the late Toarcian show again comparatively warm conditions (average: 24.4 °C; Thouarsense–Levesquei zones). Even though more material and analyses are necessary to corroborate the recorded temperatures, the present dataset seems to indicate the global nature of the Late Pliensbachian Cooling Event. In contrast, the global warming during the Toarcian Oceanic Anoxic Event has not been recorded due to a lack of Early Toarcian material. The δ13C record of brachiopods and oysters documents a gradual increase in values representing background conditions. Oyster shells were used for high-resolution stable isotope analyses and show seasonal temperature fluctuations over a period of around 3 years in the life time of the bivalves. If explained only by temperatures, the δ18O values point to a minimum estimate for the seasonality in the late Toarcian of slightly more than 3 °C.

Abstract A set of two to three prominent hardgrounds can be traced for more than 40 km from east to west within the Jurassic succession of the Jaisalmer Basin at the western margin of the Indian Craton. The hardgrounds started to form under subtidal conditions in a mixed carbonate–siliciclastic setting during the last phase of a transgressive systems tract, i.e. the maximum flooding zone. The age difference between the hardgrounds is very small, but they differ lithologically. Typically, the stratigraphically oldest hardground occurs at the top of a 1-m-thick calcareous sandstone. It is characterized by a spectacular megaripple surface encrusted with oysters and subsequently occasionally bored by bivalves. The hardground is overlain by 10–25 cm of biowackestone to biopackstone, at the top of which another hardground is developed. This second hardground is characterized by abundant bivalve (Gastrochaenolites isp.) and “worm” borings (Trypanites and Meandropolydora isp.) and occasional oyster encrustations. The third hardground can be found within the overlying 60-cm-thick, bioturbated, fossiliferous silty marly packstone. It shows common to abundant oyster encrustations and occasional borings together with reworked concretions. The individual hardground can be well recognized throughout the basin based on lithology and biotic components. The second hardground (biowackestone to biopackstone) with abundant bivalve and worm borings is most prominent and widespread. Lithostratigraphically, these three hardground surfaces belong to the uppermost part of the Bada Bag Member of the Jaisalmer Formation. Based on ammonites, such as Perisphinctes congener (Waagen), brachiopods, and corals, this interval of the Bada Bag Member has been assigned a late Bathonian age. The entire succession above the first hardground is bioturbated up to the overlying marly silt of the Kuldhar Member of the Jaisalmer Formation, which is already Callovian in age. The characteristic hardground lithologies, together with the ammonite record, allow long-distance correlations within the basin emphasizing their importance as valuable marker horizons. The biotic components associated with the hardgrounds and alternating sediments represent high diversity community relicts developed in shallow-water, open-marine environments.

Introduction: The high burden of cardiovascular morbidity and mortality in autosomal dominant polycystic kidney disease (ADPKD) is related to development of hypertension and left ventricular hypertrophy. Blood pressure reduction has been shown to reduce left ventricular mass in ADPKD; however, moderators and predictors of response to lower blood pressure are unknown. Methods: This was a post hoc cohort analysis of HALT PKD study A, a randomized placebo controlled trial examining the effect of low blood pressure and single versus dual renin−angiotensin blockade in early ADPKD. Participants were hypertensive ADPKD patients 15 to 49 years of age with estimated glomerular filtration rate (eGFR) > 60 ml/min per 1.73 m2 across 7 centers in the United States. Predictors included age, sex, baseline eGFR, systolic blood pressure, total kidney volume, serum potassium, and urine sodium, potassium, albumin, and aldosterone. Outcome was left ventricular mass index (LVMI) measured using 1.5-T magnetic resonance imaging at months 0, 24, 48, and 60. Results: Reduction in LVMI was associated with higher baseline systolic blood pressure and larger kidney volume regardless of blood pressure control group assignment (P < 0.001 for both). Male sex and baseline eGFR were associated with a positive annual slope in LVMI (P < 0.001 and P = 0.07, respectively). Conclusion: Characteristics associated with higher risk of progression in ADPKD, including higher systolic blood pressure, larger kidney volume, and lower eGFR are associated with improvement in LVMI with intensive blood pressure control, whereas male sex is associated with a smaller slope of reduction in LVMI. Keywords: autosomal dominant polycystic kidney disease, hypertension, left ventricular hypertrophy, left ventricular mass index

The uppermost part of the Upper Bathonian Sponge Limestone member, Patcham Formation, of the Jhura Dome of Kachchh Mainland is a thickening- and shallowing-upward succession topped by medium- to thick-bedded hummocky cross-stratified grainstones deposited by storm waves. Occasionally, thin, commonly lenticular, intraclastic–bioclastic silty marl intercalations between the grainstones are highly bioturbated, in contrast to the grainstones, in which, for the most part, trace fossils occur scattered. Large exposures of bedding planes of the grainstones allow the detailed investigation of ichnological features, whereas the high density of traces in the soft marls precludes the identification of any ichnotaxa. Eighteen ichnotaxa have been recorded including Ophiomorpha, Thalassinoides, Taenidium, Gyrophyllites, Chondrites, Dactyloidites, Teichichnus, Bolonia, and Ancorichnus. Except for Ophiomorpha nodosa and Thalassinoides, which generally indicate moderate to high energy conditions and are the dwelling burrows of suspension-feeding to omnivorous crustaceans, the ichnotaxa represent a deposit-feeding behaviour of their producers and thus are characteristic of low-energy environments. The trace fossils form three ichnoassemblages characterized by (1) Ophiomorpha nodosa and Thalassinoides suevicus, (2) ?Thalassinoides isp. A, Taenidium, and Bolonia lata, and (3) Ancorichnus. The dominance of traces of deposit-feeders in rocks indicative of high-energy events is counterintuitive and points to their non-contemporaneity. The sediments were deposited during brief high-energy events, whereas the trace fossils were produced when, after waning of storms low-energy conditions prevailed. This time-averaging is particularly pronounced in trace fossils that extend vertically downwards and may reach strata deposited under distinctly different conditions. Thus, environmental interpretations based on trace fossils should refer to colonisation surfaces rather than to the sediment surrounding the trace fossils. In the latter case, interpretations may be erroneous, especially when erosion subsequently destroyed sedimentary evidence of their original environment.

A high resolution study of sediments, microfaunas (ostracods and foraminifers), and stable isotopes of ostracod shells from core PRD05, sampled from the Da'ao plain of the Pearl River Delta, provides new data about palaeoenvironmental changes during the Late Quaternary. The basal fluvial gravelly sediments of the core, representing the lowest deposits of the Quaternary at the core site, were possibly formed prior to the transgression associated with the last interglacial stage. This fluvial setting changed into a marginal marine setting during the last interglacial stage, any record of calcareous fossils were destroyed by subsequent dissolution during the last glacial phase, when the upper part of the deltaic sediments experienced subaerial oxidation, indicated by a mottled clay layer in the core. The postglacial sea-level rise in the South China Sea began at ~16,700 cal yr B. P. During the first phase of sea-level rise (from ~16,700 to 10,100 cal yr B. P.), a swamp environment developed at the core site. At ~10,100 cal yr B. P., marine waters intruded onto the Da'ao plain and reached the core site through the Modaomen channel. This timing was earlier than in other parts of the Pearl River Delta. Since then, a semi-enclosed estuarine environment developed and was maintained until ~5560 cal yr B. P. During this transgressive interval, short-term environmental fluctuations can be recognized based on microfauna and shell geochemical data. From ~10,100 to 8630 cal yr B. P., the sea-level rose, which was followed by a fall from ~8630 to 8520 cal yr B. P. An expanded transgression occurred between ~8520 and 7900 cal yr B. P. The time intervals from ~8520 to 8200 cal yr B. P. and from ~8080 to 7900 cal yr B. P. were marked by peak transgression. From ~7900 to 5560 cal yr B. P., the core site generally showed a reduced marine influence and enhanced freshwater input. A fluvial environment developed from ~5560 to 3100 cal yr B. P., and was succeeded by an alluvial plain setting.

An articulated and partially preserved skeleton of an ichthyosaur was found in the Upper Jurassic (Upper Kimmeridgian) Katrol Formation exposed at a site south of the village Lodai in Kachchh district, Gujarat (western India). Here we present a detailed description and inferred taxonomic relationship of the specimen. The present study revealed that the articulated skeleton belongs to the family Ophthalmosauridae. The new discovery from India further improves the depauperate fossil record of ichthyosaurs from the former Gondwanan continents. Based on the preserved length of the axial skeleton and anterior part of the snout and taking into account the missing parts of the skull and postflexural region, it is suggested that the specimen may represent an adult possibly reaching a length of 5.0-5.5 m. The widespread occurrence of ophthalmosaurids in the Upper Jurassic deposits of western Tethys, Madagascar, South America and India points to possible faunal exchanges between the western Tethys and Gondwanan continents through a southern seaway.