STRATIGRAPHIC AND PALEOGEOGRAPHIC EVOLUTION OF A CARBONATE PLATFORM IN AN EXTENSIONAL TECTONIC REGIME: THE EXAMPLE OF THE DOLOMIA PRINCIPALE IN LOMBARDY (ITALY)

Stratigraphic and sedimentologic studies of the norian succession outcropping in rhe Lombardy Basin allowed the reconstruction of the paleogeographic and strucural evolution oi this area, 1) restricted lagoon and tidal flat are the most common deposits ar the Carnian-Norian boundary (Lower Member of the Dolomia Principale); 2) these are overlain by a thick inner platform succession organized in shallowing upwards cycles (lower Dolomia Principale), with the exception of Idro Lake area where intraplatform basin already generated; 3) the overlying middle-upper Dolomia Principale is dissected by synsedimentary faults with subsequent widespread development of intraplatform basin, margin, and slope facies with marked asymmetric distribution; the inner platform was locally emerged; 4) in the uppermost Dolomia Principale buildup margins become more abundant and the platform partially prograded on the basins; 5) at last the platform drowns and terrigenous sedimentation becomes prevalent (Riva di Solto Shales). The drowning of the platform is favoured by the lack of carbonate production, due to clay pollution and climatic changes in an area with high subsidence rates. The observed asymmetric distribution of buildup margins and fault-scarp related breccias, which outcrop on the western side of the basins west of Iseo Lake and bounding the eastern side of the basins east of Iseo Lake, allows us to propose a model of norian ensialic asymmetric rifting for the Lombardy Basin. This asymmetric rifting could be explained by interpreting the Lombardy Basin as a pull-apart basin, linked to transtension with E-W trending faults

SEDIMENTAZIONE CICLICA NEL TRIAS LOMBARDO: OSSERVAZIONI E PROSPETTIVE

High-frequency cycles are widespread in the whole Triassic succession of Lombardy (Southern Alps). These cycles characterize depositional environments ranging from continental to shallow marine to basinal, with carbonate or mixed sedimentation; their thickness is from several metres to a few millimetres. They are inferred to be the result of cyclic phenomena such as eustatic and/or tectonically controlled sea level oscillations and long term to seasonal climatic changes. The time interval covered by each of these cycles spans from the "Milankovian band" to annual. The examined Triassic succession has been arranged in depositional sequences, tentatively correlated with the third order cycles of Haq et al. (1988)

ANATOMY OF A SEMIARID COASTAL SYSTEM: THE UPPER CARNIAN OF LOMBARDY (ITALY)

The mixed terrigenous-carbonate-evaporitic  S.Giovanni Bianco  Formation  and dolomitic Campolungo  Tongue  (upper part of the Breno Formation),  generally 2OO  to  3OO  m thick, are assigned  to the Late Carnian.  They  respectively  overlie lagoonal limestones  (Gorno  Fm.)  and peritidal  carbonates  (Annunciata Member of the Breno Fm.), and underlie  intraformational  breccias  and recrystallized  limestones  (Castro Fm.). Recognition of an unconformity,  ascribed  to a relative  fall of sea-level (sequence  boundary), allowed  us to subdivide the Upper  Carnian  succession  into two parts. ln the lower part (SGBL),  six lithosomes  were recognized. Red  to green  alluvial  clastics in the south-east  and south-west  pass northward  to mixed terrigenous-carbonate  coastal sediments  and finally to dolostones  deposited  in carbonate tidal flats. In the proximal sections  of the Brescia  Prealps,  renewed  north-westward  progradation  of alluvial redbeds  with  intercalated  calclithite conglomerates  points to a stage of teconic uplift. A distinct  increase  in quartz, representing a regional  petrographic  marker  followed  all  across Lombardy, indicates  deepening  of erosion  into the metamorphic wallrocks  of the volcanic  belt. A major hiatus  at the top of the SGB1  is best documented  in the northern  Presolana  area by a silcrete crust directly overlying  the Julian Annunciata Member of the Breno Formation.  In the Brembana  Valley area, the discontinuity occurs within  a greenish  siliciclastic  coastal  plain  succession, and may be traced at the top of a marker  interval of interbedded  reddish siltstones  and sandstones. The upper part (SGB2) consists  of four lithosomes. Greenish sandstones  and siltstones,  accumulating  in coastal  plains in  the south-west,  passed  northward  to mudrocks and dolostones.  In the southernmost  Camonica Valley  area,  mudrocks  are locally interbedded  with  calcarenites  containing  bored or pedogenized  lithoclasts ripped from the underlying sequence and varied  bioclasts,  restifiying to relatively  open shallow-marine conditions  during transgression. Next, thick gypsum  accumulated in coasral  salinas  barred  by locally oolitic  platform carbonates to the north. Rare sandstone lenses  occurring  in the Brembana Valley at the top of the unit conrain  exclusive rhyolitic  detritus,  indicating either  a terminal phase of explosive  volcanism  or erosion of older  felsic volcanic products

CALCAREOUS NANNOFOSSILS AT THE TRIASSIC/JURASSIC BOUNDARY: STRATIGRAPHIC AND PALEOCEANOGRAPHIC CHARACTERIZATION

In this work, calcareous nannofossils are identified for the first time in the uppermost Triassic sequence of the Lombardy Basin (Southern Calcareous Alps, Italy). Two zones are recognized, namely the NT2b (latest Triassic) and the NJT1 (earliest Jurassic). Two species resulted to be good markers to constrain the TJB interval: Prinsiosphaera triassica and Schizosphaerella punctulata. Nannofossil data are calibrated with C isotopic chemostratigraphy obtained for carbonate and organic matter. Size reduction of P. triassica and a decline in the abundance of Triassic nannofossils are detected soon after the “precursor Carbon Isotope Excursion (CIE) and culminated during the “initial negative CIE” characterized by lowest nannofossil abundances and small-sized P. triassica. The extinction of Triassic nannofossils occurred in distinctive steps within the “initial negative CIE”, while the Jurassic S. punctulata is first observed at the base of the “main negative CIE”. The latest Triassic nannofossil decline in abundance, size reduction and extinctions, represent a progressive deterioration associated to the Central Atlantic Magmatic Province (CAMP) volcanism. Our findings are consistent with nannofossil changes at supraregional scale and indicate that the massive CAMP flood basalts were preceded by initial volcanic pulses. We speculate that a combination of climate change, fertilization and ocean acidification started to influence the calcification process prior to the “initial negative CIE”. Nannoplankton extinctions were not simultaneous and might imply limited capacity for adaptation in the early stages of evolutionary history. However, originations of new taxa soon after the disappearance of Triassic forms suggest the ability to rapidly overcame extreme stressing conditions

PERMIAN STRATIGRAPHY IN THE NORTHERN KARAKORUM, PAKISTAN

The stratigraphical data collected during four geological expeditions to the Northern Karakorum (1996,1991,1992a,1992b) are discussed. The sedimentary succession has been classified by 9 formations, here formalised, and subdivided into members and lithozones. The biochronology has been established on fusulinids, brachiopods, and conodonts. Several plates illustrate the most significant fossil species as well as the litho- and microfacies. The sedimentary succession may be roughly subdivided into three parts. The lower part consists of terrigenous rocks, mostly pelitic and less frequently arenaceous(quartzarenites with thick arkose intervals during the latest  Asselian-early Sakmarian). They are evidence of a continental to coxtal environment, with short term marine  ingressions. The second part begins with the Sakmarian, when the marine environment spread over most of the studied area. Bioclastic sand bars with brachiopods and crinoids at the base are followed by huge fusulinid packages. In Hunza oolitic bars and dolostone peritidal cycles also follow. The carbonate ramp is often polluted by terrigenous sediments, especially westwards. Temporary arenaceous spillovers (quartzarenites), often linked to minor  sedimentation gaps, occur both westwards in the Baroghil area, and eastwards in the Hunza-Shimshal area. In the centre, in the Upper  Karambar valley, a large gap most probably occurs, with reappearance of the sedimentation only with the dolostones of the Upper Permian. These erosional episodes with arenaceous spillovers are interpreted as being linked to rifting events of the Neotethys opening, active  southwards. The third part of rhe succession concerns the Late Permian. Towards the end at the Murgabian or at the beginning of the Midian, the Northern  Karakorum is subdivided into two major areas. To the west, after a transgressive episode with ironstone deposition, a wide peritidal carbonate platform spread over from Baroghil to Chillinji in Karambar and the Pasu area in Hunza. This palaeogeographic pattern extends up to the Triassic. However, biostratigraphic control is poor. Instead to the north-east, a progressive sinking of the slope is observed,  with spreading of deeper environments and cherty limestone deposition. The down-warping is activated by block-faulting resulting in huge megabreccia bodies interbedded with the cherty limestones. During the Dzhulfian, significant clay inputs dilute the carbonate mud accumulation and shales are dominant around the Permian-Triassic boundary. Pelagic carbonate sedimentation gradually recovers from the Smithian onward. The Permian of the Karakorum is the sedimentary evidence of the passive margin of a lithospheric block, detached from the Gondwana continent during the Permian, that will later migrate towards the centre  of the Paleo-Tethys, along with other lithospheric blocks of the Mega Lhasa plate

Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c

Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c

Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose diabetes, but may identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardised proportion of diabetes that was previously undiagnosed, and detected in survey screening, ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the agestandardised proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and surveillance.peer-reviewe

STRATIGRAFIA E PALEOGEOGRAFIA DEL NORICO NELLE PREALPI BERGAMASCHE OCCIDENTALI

The stratigraphy of the thick and well—bedded Norian carbonate sequence cropping out in the Southern Calcareous Alps NW of Bergamo is reviewed. The formal name Aralalta Group is introduced to include the Zorzino Limestone, the Dolomie Zonate formations and the "Brecce sommitali della Dolomia Principale" member. Five regional (A—E) and four local (Al, El, E2, E 3) facies have been distinguished in the Aralalta Group: chaotic massive breccias (A), locally bounded by encrusting organism (Al); debris flow breccias and proximal torbidites (B); torbiditic dolomitic arenites (C); thin bedded laminites— microtorbidites (D); micritic limestones, distal torbidites (E), locally thin bedded with black clay (El), bioclastic limestones with slumpings (E2) and patch reefs (E3). The Aralalta Group is time—equivalent with the upper part of the Dolomia Principale, a classic example of inner platform. The detailed study of sedimentary structures and microfacies demonstrates that the evolution of the Dolomia Principale platform margin was in Artavaggio—Val Taleggio area structurally controlled

STRATIGRAFIA E PALEOGEOGRAFIA DEL CARNICO LOMBARDO (SONDAGGIO S. GALLO, VALLE BREMBANA)

Studies on the most southern and complete Carnian sequence of the Bergamasc Alps (S. Gallo well) and of several exposed stratigraphic sections throw new light on the paleogeographic evolution and the metallogenesis of the Pb—Zn—Fluorite—Barite Gorno district. In the Early Carnian (Calcare Metallifero Bergamasco and Basal Tongue of the Gorno Fm.) , an open lagoon with mixed calcareous—terrigenous sedimentation passed northward to carbonate tidal flats and was fringed by karstified carbonate paleo—highs. Next, the great supply of terrigenous detritus from a southern volcanic belt brought about the progradation of a fluviodeltaic body (Val Sabbia Sandstone) and confined carbonate sedimentation to an outer zone