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High-resolution petrographic and heavy-mineral analyses of Bengal Fan turbidites from six cores drilled during IODP Expeditions 353 and 354 elucidate factors controlling their intersample compositional variability as a key to understanding sedimentary processes and erosional evolution of the Himalayan belt since the Miocene. Bengal Fan turbidites are feldspatho-quartzose to litho-feldspatho-quartzose with plagioclase . K-feldspar; slow-settling micas increase in abundance in very fine sand and coarse silt. The feldspar/quartz ratio and higher-rank metamorphic rock fragments notably increase from uppermost Miocene to Pleistocene deposits, which is ascribed to the onset of rapid exhumation of the Eastern Himalayan syntaxis since ~ 5 Ma. The same trends are documented in Nicobar Fan turbidites, confirming that they belong to the same sedimentary system. Both Bengal and Nicobar fans record a pulse in mass accumulation rate at Tortonian times, when supply of sedimentary and very-low-grade metasedimentary detritus reflected accelerated exhumation of the Lesser Himalaya. In contrast to foreland-basin sediments, where ferromagnesian minerals have been completely dissolved in strata as young as Pliocene–Pleistocene, in both Bengal–Nicobar and Indus fans amphibole invariably represents about half of the moderately rich to rich transparent-heavy-mineral suite, demonstrating that amphibolite-facies Greater Himalaya metamorphic rocks were widely exposed in the Himalayan range well before the late Miocene and possibly since the late Oligocene, as indicated by a few sillimanite and kyanite grains in Bengal Fan sediments as old as 23 Ma and 28 Ma, respectively. Diagenetic dissolution strongly affected olivine and pyroxene in strata older than the middle and early Pleistocene, respectively, whereas amphibole decreases markedly through progressively older Miocene strata. Ferromagnesian minerals and sillimanite are almost completely dissolved in lower Miocene strata, where durable zir

Objective Baricitinib, an oral Janus kinase (JAK) 1-2 inhibitor, is currently used along biologic DMARDs (bDMARDs) after the failure of methotrexate (MTX) in rheumatoid arthritis (RA). We investigated the efficacy and safety of baricitinib in real life. Methods We prospectively enrolled 446 RA patients treated with baricitinib from 11 Italian centres. Patients were evaluated at baseline and after 3, 6, and 12 months. They were arrayed based on previous treatments as bDMARD-naïve and bDMARD-insufficient responders (IR) after the failure or intolerance to bDMARDs. A sub-analysis differentiated the effects of methotrexate (MTX) and the use of oral glucocorticoids (OGC). Results Our cohort included 150 (34%) bDMARD-naïve and 296 (66%) bDMARD-IR patients, with 217 (49%) using baricitinib as monotherapy. Considering DAS-28-CRP as the primary outcome, at 3 and 6 months, 114/314 (36%) and 149/289 (51.6%) patients achieved remission, while those in low disease activity (LDA) were 62/314 (20%) and 46/289 (15.9%), respectively; finally at 12 months 81/126 (64%) were in remission and 21/126 (17%) in LDA. At all-timepoints up to 12 months, bDMARDs-naïve patients demonstrated a better clinical response, independently of MTX. A significant reduction in the OGC dose was observed at 3 and 12 months in all groups. The serum positivity for both rheumatoid factors (RF) and anti-citrullinated protein antibodies (ACPA) conferred a lower risk of stopping baricitinib due to inefficacy. Fifty-eight (13%) patients discontinued baricitinib due to adverse events, including thrombotic events and herpes zoster reactivation. Conclusion Real-life data confirm the efficacy and safety profiles of baricitinib in patients with RA and provide evidence that drug survival is higher in bDMARDs-naïve and seropositive patients.

Central Argentina from the Pampean flat-slab segment to northern Patagonia (27°–41°S) represents a classic example of a broken retroarc basin with strong tectonic and climatic control on fluvial sediment transport. Combined with previous research focused on coastal sediments, this actualistic provenance study uses framework petrography and heavy-mineral data to trace multistep dispersal of volcaniclastic detritus first eastwards across central Argentina for up to ca. 1,500 km and next northwards for another 760 km along the Atlantic coast. Although detritus generated in the Andes is largely derived from mesosilicic volcanic rocks of the cordillera, its compositional signatures reflect different tectono-stratigraphic levels of the orogen uplifted along strike in response to varying subduction geometry as well as different character and crystallization condition of arc magmas through time and space. River sand, thus, changes from feldspatho-litho-quartzose or litho-feldspatho-quartzose in the north, where sedimentary detritus is more common, to mostly quartzo-feldspatho-lithic in the centre and to feldspatho-lithic in the south, where volcanic detritus is dominant. The transparent-heavy-mineral suite changes markedly from amphibole ≫ clinopyroxene > orthopyroxene in the north, to amphibole ≈ clinopyroxene ≈ orthopyroxene in the centre and to orthopyroxene ≥ clinopyroxene ≫ amphibole in the south. In the presently dry climate, fluvial discharge is drastically reduced to the point that even the Desaguadero trunk river has become endorheic and orogenic detritus is dumped in the retroarc basin, reworked by winds and temporarily accumulated in dune fields. During the Quaternary, instead, much larger amounts of water were released by melting of the Cordilleran ice sheet or during pluvial events. The sediment-laden waters of the Desaguadero and Colorado rivers then rushed from the tract of the Andes wit

Understanding the evolution of river systems in southern Africa is fundamental to constrain the evolution of landscape and sediment dispersal patterns. It is widely considered that the upper Zambezi River was connected with the Limpopo River during the Cretaceous, forming what was then the largest river in Africa. Crustal flexure during the Paleogene severed the upper Zambezi drainage from the Limpopo, setting the framework of the modern Zambezi and Limpopo River systems. We present first evidence—based on heavy-mineral assemblages from cores drilled offshore of the Limpopo River mouth and samples collected in different reaches of the modern Limpopo River, integrated with magnetic susceptibility, detrital-zircon geochronology, and geomorphological analysis—suggesting that the current Limpopo River formed recently in the Plio-Quaternary. Plio-Quaternary climate change is envisaged to have controlled the recent dynamics of river drainage and consequent distribution of sediment loads, as observed in many other transcontinental rivers worldwide.

Large sediment masses are transferred over many hundreds of kilometres along the coast of passive continental margins worldwide. The relevance of such a phenomenon for source-to-sink studies, environmental issues, and coastal management remains largely unperceived. This study traces the paths of volcaniclastic sand along ca 2170 km of the Argentine coast and documents a 760 km long cell of littoral transport extending from the formerly larger Río Colorado delta to the edge of the Río de la Plata mouth. During deglaciation stages and humid periods of the Pleistocene, a much greater sediment volume than today was transferred by the Desaguadero and Colorado rivers from the highest-relief tract of the Andean Cordillera to the Atlantic Ocean. Amphibole-rich sand originally supplied by the Río Desaguadero is being recycled today from Pampean lowlands to feed the beaches along Río de la Plata southern shores, whereas pure quartzose sand of Río Paraná is found only adjacent to its prograding delta. Augite-rich sand supplied by the Río Colorado is dominant along the coast of the Buenos Aires Province, where it mixes locally with coarser-grained quartz-rich detritus recycled in the urbanized Mar del Plata area. Hypersthene-rich sand of the Río Negro is dispersed both north and south of the mouth, where heavy-mineral-rich lag deposits are formed in areas of accelerated erosion and retreating sea cliffs. Changes of mineralogical signatures during long-distance littoral transport are largely ascribed to local supply from coastal erosion or hydrodynamic effects rather than to selective breakdown of labile grains. Whereas the relative abundance of amphibole and pyroxene is largely independent of transport distance, olivine is depleted both in the northern part of the Colorado littoral cell and south of the Río Negro mouth, which is chiefly ascribed to dilution by recycling of Neogene sediments that have undergone early intrastratal dissolution rather than to mec

Epidote group minerals are one of the three most abundant kinds of heavy minerals in orogenic sediments, the other two being amphibole and garnet. They resist diagenesis better than amphibole and resist weathering in soils better than garnet. Their chemical composition and optical properties vary markedly and systematically with temperature and pressure conditions during growth. Useful information on the metamorphic grade of source rocks can thus be obtained by provenance analysis. In this study, we combine optical, SEM–EDS, and Raman analyses of nine standard crystals of epidote group minerals collected from different rock units exposed in the European Alps and Apennines and develop a Raman library for efficient discrimination of epidote, clinozoisite, zoisite, and allanite by establishing clear user-oriented relationships among optical properties, chemical composition, and Raman fingerprint. This new library allows us to distinguish and reliably determine, directly from their Raman spectrum, the chemical compositions of epidote group minerals during routine heavy mineral analyses of sand/sandstone and silt/siltstone samples down to the size of a few microns. The validity of the approach is illustrated by its application to 41 Bengal Fan turbidites collected from five cores during IODP Expedition 354 and ranging in grain size from medium sand to fine silt.

We here review in terms of tectono-magmatic setting and Quaternary landscape dynamics what is known about the provenance of Argentine dune fields and their fluvial feeder systems draining the Andean Cordillera. The detrital signatures of these eolian sediments were previously investigated based on either framework petrography and heavy minerals or detrital-zircon geochronology, and their peculiar volcaniclastic nature was long recognized. Compositional variability, however, was only broadly evaluated, and quantitative provenance analysis based on a systematic multimethod approach across the entire region was not carried out so far. For this reason, here we integrate original and previously obtained petrographic, heavy-mineral, and detrital-zircon geochronology data to present the first comprehensive provenance study of dune fields stretching for 1000 km across central Argentina from the Andean piedmont to the Atlantic Ocean. In dune fields along the Andean retroarc basin, sediment composition defines a steady northward decrease in volcanic detritus. This reflects active magmatism in the Southern Volcanic Zone and Payenia province (38°-34°S), in contrast with the ~600-km-long Pliocene-Quaternary magmatic gap in the Pampean flat-slab segment (33°-27°S), where sediment is derived from deeper-seated tectono-stratigraphic levels of the continental arc and uplifted blocks of retroarc-basin basement. In distal Pampean lowlands extending across the bulge and backbulge depozones, instead, sand dunes display notably homogeneous compositional signatures, indicating that detritus was mostly generated north of 34°S and transported by a paleo-Desaguadero trunk river that formed during southward-progressing diachronous uplift of the Sierras Pampeanas since the late Miocene. In contrast with huge African and Arabian deserts that contain multiply recycled quartzose to pure quartzose sand, even very fragile volcanic clasts, plagioclase feldspar, and unstable ferromagnesian minerals a

The Nicobar Fan and Bengal fans can be considered as the eastern and western parts, respectively, of the largest submarine-fan system in the world. This study presents the integrated results of petrographic and provenance studies from the Nicobar Fan and evaluates these in the context of controls on sedimentation. Both fans were predominantly supplied by Himalaya-derived material from the main tectono-stratigraphic sequences as well as the Gangdese arc. A lack of volcanic material in the Nicobar Fan rules out sources from the Sumatra magmatic arc. Overall, the petrographic data shows a progressive decrease in sedimentary detritus and corresponding increase of higher-grade metamorphic detritus up-section. Changes in sediment provenance and exhumation rates in the Himalaya are seen to track changes in sediment accumulation rates. High sediment accumulation rates in the Bengal Fan occurred at ∼13.5–8.3 Ma, and in the Nicobar Fan from ∼9.5–5 Ma. Both fans show peak accumulation rates at 9.5–8.3 Ma (but with the Nicobar Fan being about twice as high), and both record a sharp drop from ∼5.5–5.2 Ma, that coincided with a change in river drainage associated with the Brahmaputra River diverting west of the uplifting Shillong Plateau. At ∼5 Ma, the Nicobar Fan was supplied by an eastern drainage route that finally closed at ∼2 Ma, when sediment accumulation rates in the Nicobar Fan significantly decreased. Sediment provenance record these changes in routing whereby Bengal Fan deposits include granitoid sources from the Namche Barwa massif in the eastern syntaxis that are not seen in the Nicobar Fan, likely due to a more localised eastern drainage that included material from the Indo-Burman wedge. Prior to ∼3 Ma, source exhumation rates were rapid and constant and the short lag-time rules out significant intermediate storage and mixing. In terms of climate versus tectonic controls, tectonically driven changes in the river network have had most influence on fan sedimentation.

The Bangladesh lowlands are traversed by the largest sediment flux on the planet. Detritus generated mostly in Himalayan highlands and conveyed through the Ganga–Brahmaputra rivers and Meghna estuary reaches the Bay of Bengal, where it forms a composite deltaic system. This study integrates the vast existing database on Ganga–Brahmaputra sediments of all grain sizes from clay to sand with new petrographic, mineralogical, and geochemical data on estuarine and shallow-marine sands. A large spectrum of compositional signatures was used to: (i) assess the relative supply of the Ganga and Brahmaputra rivers to estuarine and shelfal sediments; (ii) define the compositional variability of estuarine sediments and the impact exerted by hydraulic sorting and climate-related chemical weathering on provenance signals; (iii) define the compositional variability of shelf sediments and the potential hydrodynamic segregation of fast-settling heavy minerals in coastal environments and of slow-settling platy micas on low-energy outer-shelf floors; (iv) consider the potential additional mud supply from the western subaerial part of the delta formerly built by the Ganga River; and (v) draw a preliminary mineralogical comparison between fluvio-deltaic sediments and turbidites of the Bengal–Nicobar deep-sea fan, thus tracing sediment dispersal across the huge sedimentary system extending from Tibet to the equatorial Indian Ocean. All investigated mineralogical and geochemical parameters, as well as Sr and Nd isotope ratios and clay–mineral assemblages, showed a clear prevalence in sediment supply from the Brahmaputra (60–70%) over the Ganga (30–40%). Heavy-mineral suites and Sr and Nd isotope fingerprints of Bengal shelf sediments are nearly identical to those of the Brahmaputra River and Meghna estuary, also because the Brahmaputra carries almost twice as many Ca-plagioclase grains and heavy minerals including epidote than the Ganga, and these minerals control the large majority of the

The Indo-Burman Ranges (IBR) are a mountain range comprised of Mesozoic-Cenozoic rocks which run the length of Western Myanmar, extending into India and Bangladesh; to the west lies the Indian Ocean, and to the east lies the Central Myanmar Basin (CMB) along which the Irrawaddy River flows. The IBR are considered to be an accretionary prism, developed at the juncture of the Indian and Sunda plates, and a number of hypotheses have been proposed for their evolution. However, in order for these hypotheses to be evaluated, the timing of IBR evolution needs to be determined. We undertook a two-pronged approach to determining the timing of uplift of the IBR. (1) We present the first low-temperature thermochronological age elevation profiles of the IBR using ZFT, AFT and ZHe techniques. Our data show: a major period of exhumation occurred around the time of the Oligo-Miocene boundary; we tentatively suggest, subject to further verification, an additional period of exhumation at or before the late Eocene. (2) We carried out a detailed multi-technique provenance study of the sedimentary rocks of the IBR and Arakan Coastal region to their west, and compared data to coeval rocks of the CMB. We determined that during Eocene times, rocks of the CMB and IBR were derived from similar local provenance, that of the Myanmar arc to the east. Therefore at this time there was an open connection from arc to ocean. By contrast, by Miocene times, provenance diverged. Rocks of the CMB were deposited by a through-flowing Irrawaddy River, with detritus derived from its upland source region of the Mogok Metamorphic Belt and Cretaceous-Paleogene granites to the north. Such a provenance is not recorded in coeval rocks of the IBR, indicating that the IBR had uplifted by this time, providing a barrier to transport of material to the west. To the previously published list of viable proposals to explain the exhumation of the range, we add a new suggestion: the period of exhumation around the time of

Analysis of sedimentary materials using a portable luminescence reader (or portable optically stimulated luminescence reader POSL), is a useful, rapid (a few minutes per sample), cost-effective and safe (not requiring exposure to chemicals) way to establish relative sample age. Moving beyond information that guides initial field interpretations, or develops targeted sampling strategies for full laboratory-based dating protocols, toward rapid age assessment has been more challenging. This study is the first demonstration of a simple, elegant and practical calibration of POSL signals into sample age estimates. This involved measuring the POSL signals from 144 samples with established published ages from across southern Africa, and a regression analysis. The data show that a regional-specific approach to calibration is needed, with regional patterns in POSL signals that are supported by 148 further undated samples. Four broad regions are defined: the Namib Sand Sea (NSS), the northern Kalahari (barchan dunes on the floor of Makgadigadi) (Nnk-MBa), the western Kalahari (WK) and the southern Kalahari (SK). Sample composition data, such as quartz-to-feldspar ratios (Q/F) appears to account for the largest contrasts within the dataset, whilst inherent POSL signal brightness and grain coloured-coatings (iron and clay) may also influence signals. The strength of the regressions (R2 of 0.99, 0.93, 0.81 and one moderate at 0.52 for the NSS, SK, WK and NnK-MBa respectively) between POSL signals and sample age, (for ages back to 118, 104 74 and 5 ka for the NSS, SK, WK and NnK-MBa respectively), demonstrates the practicality and huge value of this simple approach. The implication is that region-specific calibrations must be built prior to using the POSL reader for rapid age assessments. This approach is a cost and time-effective method for inter-dunefield landscape-scale analyses, which will cast light on the key climatic variables driving landscape change in sand-rich drylands

Major deserts do not necessarily consist of eolian dunes as quartz-rich as those of the Great Nafud, Rub' al Khali, Sahara, and Mega-Kalahari sand seas accumulated in anorogenic settings of Arabia and Africa. The Karakum dune field of Turkmenistan is one of the several examples of central Asian deserts bound by recent or recently reactivated orogenic belts where eolian sand includes abundant sedimentary and subordinately metamorphic and volcanic lithic fragments. Feldspatho-litho-quartzose detrital modes and epidote-amphibole-garnet heavy-mineral suites of southern Karakum dune sand compare well with those in mountain branches of the Amu Darya, indicating provenance from the western Pamir mountains of Tajikistan in the east. Dunes closer to the Caspian Sea in the west contain additional carbonate or felsic volcanic grains which, together with decreasing heavy-mineral concentration and increasing ZTR indices, reveals local recycling of cover strata exposed in the Kopeh-Dagh and Balkhan zone. Our data suggest that the huge Amu Darya River, which in Plio-Pleistocene to historical times has repeatedly changed its course across Turkmenistan from westward toward the Caspian Sea to northward toward the Aral Sea, represents the major sediment source for the Karakum Desert. Together with the Taklamakan sand sea of the Tarim basin, the Ordos and adjacent deserts of northern China, and the Thal and Thar deserts of the western Himalayan foreland basin, the Karakum would thus represent another example of large dune field principally fed by one major fluvial feeder system.

A never solved problem in sedimentary petrology is the origin of sandstone consisting exclusively of quartz and most durable heavy minerals. The Congo River offers an excellent test case to investigate under which tectonic, geomorphological, climatic, and geochemical conditions pure quartzose sand is generated today. In both upper and lowermost parts of the catchment, tributaries contain significant amounts of feldspars, rock fragments, or moderately stable heavy minerals pointing at the central basin as the main location of the “quartz factory”. In Congo sand, quartz is enriched relatively to all other minerals including zircon, as indicated by Si/Zr ratios much higher than in the upper continental crust. Selective elimination of old zircons that accumulated radiation damage through time is suggested by low percentages of grains yielding Archean U–Pb ages despite the basin being surrounded by Archean cratonic blocks. Intense weathering is documented by the lack of carbonate grains in sand and by dominant kaolinite and geochemical signatures in mud. In sand, composed almost entirely of SiO2, the weathering effect is masked by massive addition of quartz grains recycled during multiple events of basin inversion since the Proterozoic. Changes in mineralogical, geochemical, and geochronological signatures across Bas-Congo concur to suggest that approximately 10% of the sand supplied to the Atlantic Ocean is generated by rapid fluvial incision into the recently uplifted Atlantic Rise. The Congo River connects with a huge canyon ~30 km upstream of the mouth, and pure quartzose sand is thus funnelled directly toward the deep-sea to feed a huge turbidite fan. Offshore sediments on both sides of the canyon are not derived from the Congo River. They reflect mixed provenance, including illite-rich dust wind-blown from the arid Sahel and augite, hypersthene, and smectite ejected from volcanic centres probably situated along the Cameroon Line in the north. Because mixing of detr

This Nile Delta case study provides quantitative information on a process that we must understand and consider in full before attempting provenance interpretation of ancient clastic wedges. Petrographic and heavy-mineral data on partly lithified sand, silt, and mud samples cored from the up to 8.5 km-thick post-Eocene succession of the offshore Nile Delta document systematic unidirectional trends. With increasing age and burial depth, quartz increases at the expense of feldspars and especially of mafic volcanic rock fragments. Heavy-mineral concentration decreases drastically, transparent heavy minerals represent progressively lower percentages of the heavy fraction, and zircon, tourmaline, rutile, apatite, monazite, and Cr-spinel relatively increase at the expense mainly of amphibole in Pliocene sediments and of epidote in Miocene sediments. Recent studies have shown that the entire succession of the Nile Delta was deposited by a long drainage system connected with the Ethiopian volcanic highlands similar to the modern Nile since the lower Oligocene. The original mineralogy should thus have resembled that of modern Delta sand much more closely than the present quartzose residue containing only chemically durable heavy minerals. Stratigraphic compositional trends, although controlled by a complex interplay of different factors, document a selective exponential decay of non-durable species through the cored succession that explains up to 95% of the observed mineralogical variability. Our calculations suggest that heavy minerals may not represent >20% of the original assemblage in sediments buried less than ~1.5 km, >5% in sediments buried between 1.5 and 2.5 km, and >1% for sediments buried >4.5 km. No remarkable difference is detected in the intensity of mineral dissolution in mud, silt, and sand samples, which argues against the widely held idea that unstable minerals are prone to be preserved better in finer-grained and therefore presumably less permea

High-resolution sand petrography and heavy mineral analyses help to frame U-Pb age and Hf isotope data from zircon grains, integrated in turn with geochemical data from detrital apatite, rutile, garnet, and monazite, and with Raman spectroscopy data from detrital amphibole, pyroxene, and epidote-group minerals. This multitechnique approach, including stream-profile analysis, was used to characterize components of the sediment flux and define erosion patterns across the Lhasa block, a complex continental-arc terrane caught in the Himalayan collision. Litho-feldspatho-quartzose detrital modes and hornblende-dominated heavy mineral assemblages suggest that the majority (four fifths) of the sand bed load in the Lhasa River catchment is derived from erosion of granitoid batholiths. Gravel composition, however, is markedly different and dominated by volcanic pebbles in the trunk river, as in all of its four major tributaries, testifying to an order-of-magnitude difference in apparent erosion rates between granitoid batholiths and arc lavas. This marked contrast, partly explained by wide exposures of granitoid rocks in the rugged Nyainqêntanglha Range characterized by active incision, is notably amplified by the high sand-generation potential of granitoid rocks, which, in contrast to dense joint blocks of andesitic lavas, tend to disintegrate to sandy grus upon weathering. Sedimentary strata, making up a good half of exposed rocks, are also underrepresented in sand bed load, suggesting selective mechanical breakdown of nondurable shale/slate grains. This exposes a serious bias affecting estimates based on sand only, and it highlights the necessity for taking into account the entire size spectrum from mud to gravel in order to improve the accuracy of sediment budgets. Provenance analysis should involve multiple methods applied to multiple minerals, rather than be based solely on a single rare mineral, even if it is exceptionally laden with potential provenance information

Heavy minerals are typically rare but important components of siliciclastic sediments and rocks. Their abundance, proportions, and variability carry valuable information on source rocks, climatic, environmental and transport conditions between source to sink, and diagenetic processes. They are important for practical purposes such as prospecting for mineral resources or the correlation and interpretation of geologic reservoirs. Despite the extensive use of heavy mineral analysis in sedimentary petrography and quite diverse methods for quantifying heavy mineral assemblages, there has never been a systematic comparison of results obtained by different methods and/or operators. This study provides the first interlaboratory test of heavy mineral analysis. Two synthetic heavy mineral samples were prepared with considerably contrasting compositions intended to resemble natural samples. The contributors were requested to provide (i) metadata describing methods, measurement conditions and experience of the operators and (ii) results tables with mineral species and grain counts. One hundred thirty analyses of the two samples were performed by 67 contributors, encompassing both classical microscopic analyses and data obtained by emerging automated techniques based on electron-beam chemical analysis or Raman spectroscopy. Because relatively low numbers of mineral counts (N) are typical for optical analyses while automated techniques allow for high N, the results vary considerably with respect to the Poisson uncertainty of the counting statistics. Therefore standard methods used in evaluation of round robin tests are not feasible. In our case the ‘true’ compositions of the test samples are not known. Three methods have been applied to determine possible reference values: (i) the initially measured weight percentages, (ii) calculation of grain percentages using estimates of grain volumes and densities, and (iii) the best-match average calculated from the most reliable analyses f

Background: Successful rehabilitation is associated with physical, psychological, environmental, social, and personal factors based on the International Classification of Functioning, Disability and Health (ICF) framework. The influence of age has been suggested as crucial personal factors that may affect rehabilitation needs in post-stroke survivors. The aim of this study was to investigate the qualifiers of the ICF core set for stroke to detect differences in rehabilitation needs and goals between older (O, >65 years old) and younger (Y, ≤65 years old,) post-stroke individuals. Materials and methods: In this observational study, the comprehensive core set for stroke was filled during the rehabilitation period. Patient information was obtained using disability scales was translated into certain ICF categories using linking rules. Frequency, similarity, and linear regression analyses were performed for ICF qualifier profiles among Y and O patients. Results: Forty-eight ICF variables were significantly different between Y (n = 35, 46.17 ± 11.27 years old) and O (n = 35, 76.43 ± 6.77 years old) patients. Frequency analysis showed that activity of daily living and basic needs were more prevalent in O patients, whereas regaining of social role and social life were more prevalent in Y patients. The average Jaccard Index result (similarity analysis) was more homogeneous in O than in Y patients. Conclusions: ICF qualifiers are useful to design patient-centered care. Y patients have more heterogeneous needs and require more personalized program than O patients.

Antisynthetase syndrome (ASSD) is a rare clinical condition that is characterized by the occurrence of a classic clinical triad, encompassing myositis, arthritis, and interstitial lung disease (ILD), along with specific autoantibodies that are addressed to different aminoacyl tRNA synthetases (ARS). Until now, it has been unknown whether the presence of a different ARS might affect the clinical presentation, evolution, and outcome of ASSD. In this study, we retrospectively recorded the time of onset, characteristics, clustering of triad findings, and survival of 828 ASSD patients (593 anti-Jo1, 95 anti-PL7, 84 anti-PL12, 38 anti-EJ, and 18 anti-OJ), referring to AENEAS (American and European NEtwork of Antisynthetase Syndrome) collaborative group's cohort. Comparisons were performed first between all ARS cases and then, in the case of significance, while using anti-Jo1 positive patients as the reference group. The characteristics of triad findings were similar and the onset mainly began with a single triad finding in all groups despite some differences in overall prevalence. The "ex-novo" occurrence of triad findings was only reduced in the anti-PL12-positive cohort, however, it occurred in a clinically relevant percentage of patients (30%). Moreover, survival was not influenced by the underlying anti-aminoacyl tRNA synthetase antibodies' positivity, which confirmed that antisynthetase syndrome is a heterogeneous condition and that antibody specificity only partially influences the clinical presentation and evolution of this condition.

The subequatorial Angolan continental margin offers excellent conditions to test textbook theories on the composition of passive-margin sediments generated in different climatic and tectonic regimes. We use here comprehensive petrographic, heavy-mineral, geochemical and zircon-geochronology datasets on modern fluvial, beach, shelfal, and deep-marine sands and muds collected from hyperarid northern Namibia to hyperhumid Congo to investigate and assess: a) how faithfully sand mineralogy reflects the lithological and time structures of source rocks in a tectonically active rifted margin; b) in what climatic and geomorphological conditions the mark of chemical weathering becomes strong and next overwhelming; and, c) to what extent the effect of weathering can be isolated from quartz dilution by recycling of older siliciclastic strata and other physical controls including hydraulic sorting and mechanical wear. A new refined classification of feldspatho-quartzose and quartzose sands and sandstones is proposed. First-cycle quartzo-feldspathic to feldspar-rich feldspatho-quartzose sand eroded from mid-crustal granitoid gneisses of the Angola Block exposed in the dynamically uplifted Bié-Huila dome is deposited in arid southern Angola, whereas quartz-rich feldspatho-quartzose to quartzose sand characterizes the lower-relief, less deeply dissected, and more intensely weathered rifted margin of humid northern Angola. Pure quartzose, largely recycled sand is generated in the vast, low-lying hyperhumid continental interiors drained by the Congo River. The progressive relative increase of durable minerals toward the Equator results from three distinct processes acting in accord: active tectonic uplift in the arid south, and progressively stronger weathering coupled with more extensive recycling in the humid north. The quartz/feldspar ratio increases and the plagioclase/feldspar ratio decreases rapidly in first-cycle sand generated farther inland in the Catumbela catchment, refle

The Chinese Loess Plateau, the world’s largest and oldest loess record, preserves evidence of Asia’s long-term dust source dynamics, but there is uncertainty over the source of the deposits. Recent single-grain detrital zircon U-Pb age analysis has progressed this issue, but debates remain about source changes, and the generation and interpretation of zircon data. To address this, we analyze different groupings of new and existing datasets from the Loess Plateau and potential sources. We also present the results of a first high resolution sampling, multi-proxy provenance analysis of Beiguoyuan loess using U-Pb dating of detrital zircons and detrital garnet geochemistry. The data shows that some small source differences seem to exist between different areas on the Loess Plateau. However, sediment source appears to be unchanging between loess and palaeosols, supporting a recent material recycling hypothesis. Our zircon and garnet data demonstrates, however, that Beiguoyuan experienced a temporary, abrupt source shift during the last glacial maximum, implying that local dust sources became periodically active during the Quaternary. Our results highlight that grouping data to achieve bigger datasets could cause identification of misleading trends. Additionally, we suggest that multi-proxy single-grain approaches are required to gain further insight into Chinese Loess Plateau dust sources

This study focuses on the causes, modalities and obstacles of sediment transfer in the longest cell of littoral sand drift documented on Earth so far. Sand derived from the Orange River is dragged by swell waves and persistent southerly winds to accumulate in four successive dunefields in coastal Namibia to Angola. All four dunefields are terminated by river valleys, where aeolian sand is flushed back to the ocean; and yet sediment transport continues at sea, tracing an 1800 km long submarine sand highway. Sand drift would extend northward to beyond the Congo if the shelf did not become progressively narrower in southern Angola, where drifting sand is funnelled towards oceanic depths via canyon heads connected to river mouths. Garnet–magnetite placers are widespread along this coastal stretch, indicating systematic loss of the low-density feldspatho-quartzose fraction to the deep ocean. More than half of Moçamedes Desert sand is derived from the Orange River, and the rest in similar proportions from the Cunene River and from the Swakop and other rivers draining the Damara Orogen in Namibia. The Orange fingerprint, characterized by basaltic rock fragments, clinopyroxene grains and bimodal zircon-age spectra with peaks at ca 0·5 Ga and ca 1·0 Ga, is lost abruptly at Namibe, and beach sands further north have abundant feldspar, amphibole-epidote suites and unimodal zircon-age spectra with a peak at ca 2·0 Ga, documenting local provenance from Palaeoproterozoic basement. Along with this oblique-rifted continental margin, beach placers are dominated by Fe–Ti–Cr oxides with more monazite than garnet and thus have a geochemical signature sharply different from beach placers found all the way along the Orange littoral cell. High-resolution mineralogical studies allow us to trace sediment dispersal over distances of thousands of kilometres, providing essential information for the correct reconstruction of ‘source to sink’ re

A practical classification of surface textures observed on detrital grains in sands and sandstones is proposed, in order to enhance data reproducibility among operators and to implement the use of high-resolution heavy-mineral data in studies of sediment-generation, provenance, and diagenesis. Five stages of progressive weathering (unweathered, corroded, etched, deeply etched, skeletal) are recognized for diverse detrital minerals. Archetypal grains displaying increasing degrees of corrosion are illustrated in numerous color tables for visual comparison. This catalog, specifically devised to systematically collect valuable information for paleoclimatic or diagenetic interpretation during routine grain-counting under the microscope, is here shown to represent a useful subsidiary tool to reveal the different degrees of weathering for diverse minerals in modern sands of equatorial Africa, and to identify post-depositional modifications of detrital assemblages in buried orogenic sediments of the Bengal Basin. The data thus obtained need to be interpreted by carefully considering the concentration of heavy minerals in each sample, which provides the fundamental clue to quantify the degree of heavy-mineral depletion caused by either pre-depositional or post-depositional processes. The scrutiny of dissolution effects has applications in the study of the chemical properties of minerals and of diagenetic evolution, helping us to understand the development of secondary porosity and to assess the potential of water and hydrocarbon reservoirs.

Interpretation of the origin of Oligocene Flysch exposed in the Andaman-Nicobar Islands has been the subject of debate. Previous work on the provenance of the Andaman Flysch based on samples from South Andaman has indicated major contributions from Myanmar affected by the India-Asia collision, mixed with subordinate detritus from the nascent Himalayas. This study examines the provenance of a larger suite of samples that extend to North and Middle Andaman islands as well as Great Nicobar Island. Rather monotonous petrographic and heavy-mineral assemblages testify to strong diagenetic imprint, leading to a poorly constrained identification of the sediment source. U-Pb zircon ages provide more robust and diagnostic provenance discrimination between the Myanmar Arc and the growing Himalayan range. Combining petrographic and min- eralogical data with detrital zircon U-Pb analyses, we find that most of the Andaman Flysch is dominated by a strong continental-crust signal with only a minor contribution from arc material. Statistical analyses of the data show that most of the samples have a provenance similar to Palaeogene Bengal Fan sediments, although the type section on South Andaman has a closer affinity to the provenance of the modern Irrawaddy.