Miracle-dz/UniFAR-FTUs huggingface dataset:
River-Island Morphological Response to Basin Land-Use Change within the Jaguaribe River Estuary, NE Brazil

ABSTRACT Godoy, M.D.P. and de Lacerda, L.D. , 2014. River-island morphological response to basin land-use change within the Jaguaribe River estuary, NE Brazil. The Jaguaribe River drains the largest watershed of the Ceará state in northeastern Brazil, which, with a catchment of approximately 75,000 km2, comprises more than 50% of the total state area. Land use and global climate changes are altering the river morphology, making navigation in the estuary difficult. Mapping of fluvial islands using images from the Landsat 5 between 1988 and 2010 showed that the existing islands in the estuary suffered great changes during this period. Overall, there was an increase of 24.15 ha in the area of the islands, which are presently being colonized by mangrove vegetation. The period of largest growth occurred between 1992 and 2003, when there was an increase of 13 ha at a rate of 2.7 ha y−1. An estimate of the sediment loading from various land uses in the watershed showed that the main activity contributing to sediments to the estuary is agriculture (282,322 t y−1), with the main contributions stemming from plantations of beans, cassava, and corn; the second-most important source of sediments is urban runoff (115,076 t y−1), followed by shrimp farms (13,475 t y−1) and livestock (1374 t y−1). The increased rate of sedimentation in the estuary caused by land-use drivers is aggravated by the decrease in river flow caused by damming and the decrease in rainfall over the basin caused by global climate change.
Intrinsic and extrinsic controls of spatial and temporal variations in modern fluvial tufa sedimentation: A thirteen‐year record from a semi‐arid environment

Sedimentological and hydrochemical parameters of the River Piedra (north‐east Spain) were monitored every six months (from 1999 to 2012) at 24 sites, at which tablets were installed all along the river. The river water is of HCO3–SO4–Ca type and is notably influenced by inputs from upstream karstic springs. Tufa deposition was first detected 8 km downstream of these springs and greatly increased from there, primarily along the steeper stretch (i.e. within the Monasterio de Piedra Natural Park); then, deposition decreased through the most downstream stretch, with smaller ground water inputs. The spatial evolution of the tufa thickness, with parallel variations of PWP (Plummer, Wigley, Parkhurst) rates, was thus determined by the river water pCO2 which was controlled by ground water inputs and by the river bed slope. Five fluvial subenvironments and seven sedimentary facies were characterized. The water flow conditions are the primary factor responsible for the distinct deposition rates of facies, mainly through CO2‐outgassing. Stromatolites and moss‐tufa and alga‐tufa had the highest rates, whereas loose tufa formed in slow‐flowing water and tufa of spray areas had thinner deposition. A six‐month pattern in the deposition rate was detected through thickness measurements. That pattern was parallel to the seasonal PWP rates. The increased deposition during warm periods (spring and summer; mean: 5·08 mm) compared with cool periods (autumn and winter; mean: 2·77 mm) is linked chiefly to temperature, which controlled the seasonal changes in the physico‐chemical and biological processes; this finding is supported by a principal components analysis. Seasonal variations of insolation and day duration also contributed to such a deposition pattern. Large discharge events, which provoked erosion of tufa deposits and dilution of water, caused the reversal of the seasonal deposition rate pattern. Stromatolites are likely to preserve the most complete sedimentary record. Although tufas are a potentially sensitive record of climate‐related parameters, erosion is an intrinsic process that may overwhelm the effects of such parameters. This issue should be considered in palaeoclimatic studies based on the tufa record, particularly in semi‐arid conditions.
Quantifying Transient Soil Moisture Dynamics Using Multipoint Direct‐Current Resistivity in Homogeneous Sand

Direct measurements of soil moisture are extremely difficult to obtain between the spatial scales of point measurements and remote sensing. Nevertheless, the spatiotemporal distribution of soil moisture remains a key variable in hydrology. In this study, we explored the use of multipoint direct‐current resistivity to examine spatiotemporal changes in soil moisture following a rapid infiltration event into a large macropore. The methodology was selected because the time scale of flow processes in the homogeneous isotropic sand prevented the use of imaging techniques. Selection of an appropriate electrode array was critical for collecting the required high‐resolution spatiotemporal resistivity measurements in a 1.44‐m‐diameter tank. Direct placement of a dense array of electrodes in the sand allowed us to use geostatistical methods for spatial interpolation, thereby removing the inherent uncertainty resulting from inversion mechanics (i.e., smoothness constraints for underconstrained problems). Instead, conversion of resistivity to saturation was directly performed using Archie's law. We compared the observations to a two‐dimensional, axisymmetric, numerical solution of the system using the HYDRUS 2D/3D software, and to a semianalytical solution to estimate soil hydraulic properties. We found satisfactory comparisons among the observations and the numerical and semianalytical solutions of the system, which indicates that these techniques may be applicable to field‐scale estimates of effective hydraulic properties. Subject to limiting initial conditions, boundary conditions, and material properties, the results of the semianalytical solution are encouraging for capturing general hillslope‐scale dynamics at longer temporal scales toward a greater understanding of emergent patterns in dryland ecosystems.
Climatic conditions during marine oxygen isotope stage 6 in the eastern Mediterranean region from the isotopic composition of speleothems of Soreq Cave, Israel

At several times during marine oxygen isotope stage 6, the eastern Mediterranean region was influenced by two extreme climatic systems: the large ice sheet over northern Europe and the wet tropics associated with African monsoons. During this interval, two major climatic events occurred in the region; the sapropel S6 layer formed ca. 176 ka in the eastern Mediterranean basin owing to the increase in the African monsoon, and another event, although not large enough to form sapropel, occurred ca. 151 ka. The isotopic composition of Soreq Cave speleothems seems to record these events as very low δ 18 O-δ 13 C values dated as ca. 178 and 152 ka. The very low δ 18 O-δ 13 C values of −6‰ and −11‰ to −12‰, respectively, are typical of interglacial intervals, but here they were recorded during a glacial interval. Such low peaks indicate that in this part of the eastern Mediterranean region, i.e., Israel, the rainfall amount increased dramatically. Moreover, the isotopic record of the speleothems also shows that during the entire stage 6, although the climate was as cold as much of the last glacial, the conditions were never as dry.
SHALLOW BURIAL DOLOMITIZATION AND DEDOLOMITIZATION OF CENOZOIC COOL-WATER LIMESTONES, SOUTHERN AUSTRALIA: GEOCHEMISTRY AND ORIGIN

ABSTRACT The Gambier Limestone, a bryozoan-rich, cool-water carbonate of Late Eocene to Early Miocene age in the Otway basin of southeastern Australia, is about one-third variably dolomitized limestone and dolostone. Individual dolomite crystals range from 10 to 500 µm and are of three types: (1) silt-size crystals (4-64 µm diameters) having a brightly luminescent core (10-20 µm) of nearly stoichiometric dolomite with 1 mol% MnCO3 and SiO2 but no Fe, surrounded by a thin, dull or alternating dark and bright CL cortex that is nonstoichiometric with 44-46 mol % MgCO3 but sharp to diffuse zoning in Mn and Fe, (2) sand-size crystals, which also have a brightly luminescent and stoichiometric core and dark and bright non-stoichiometric thin inner cortex, but are mostly a thick outer cortex (at ca. > 50 µm diameter) that is nonluminescent and nonstoichiometric with some Fe but no Mn, and (3) identical sand-size crystals with a variably leached core and inner cortex that is either a void or a void filled with late calcite cement. These three crystal populations represent two distinct dolomites and their alteration product. The smallest of the silt-size crystals, which are rarely preserved, are also the cores of the larger crystals upon which grew an inner and outer cortex of somewhat different composition. The 18O values of dolomite rhombs (-1.6 to 2.9 ) correlate positively with 13C values (0.7 to 3.0), with the lowest values from silt-size or small sand-size crystals and the highest values from large sand-size crystals with leached, unfilled cores. Low and variable 18O and 13C values in conjunction with high and variable Mn and Fe contents in both the core and inner cortex of all crystals are consistent with formation from a mixture of brackish water and seawater. Higher values for the outer cortex in sand-size crystals are typical of those expected for precipitation from normal or near-normal seawater. Low Sr, Mn, and Fe contents in the largest crystals, in conjunction with fluid inclusions of seawater salinity in the outer cortex, are also consistent with the bulk of the large crystals having precipitated from seawater. Using the Sr-isotope evolution curve for Cenozoic seawater, Sr-isotope ratios of the dolomites can be divided into four distinct groups, which correspond to times of major transgressions. This Cenozoic example, in which dolomite petrography and crystal chemistry can be explained in terms of simple transgression-regression, offers a simple sedimentological explanation for many similar dolomites where processes of formation cannot be so easily constrained.
A quantitative model of grain size and sedimentary structures in lateral deposits

The secondary flow and transverse changes of water depth in curved stream channels are exploited to develop a quantitative, partly empirical model of the way lithology varies vertically in deposits accumulated through processes of lateral deposition. According to the model, grain size decreases upward in a lateral deposit and the sedimentary structures change from those denoting large stream powers upward to kinds indicative of small powers. The model also shows that the proportion of flat-bedded sand-grade material in a lateral deposit is essentially independent of stream power but controlled by channel curvature and hence general sinuosity. The predictions of the model compare satisfactorily with the characteristics of selected coarse members in fining-upwards cycles of fluviatile origin from Devonian strata in Britain and North America. The model is thought to have value as a tool for environmental interpretations.
Chute cutoff as a morphological response to stream reconstruction: The possible role of backwater

Stream restoration efforts often aim at creating new unconstrained meandering channels without weirs and bank revetments. In reconstructed streams, the initial morphological response of the new streams is often rapid, until a dynamic equilibrium is reached. Here we report on a chute cutoff that occurred within 3 months after realization of a stream restoration project, caused by a plug bar that formed in response to a backwater effect. The temporal evolution of the morphology of both the new and the old channels was monitored over a period of nearly 8 months, including precutoff conditions. The observations can be separated into three stages. Stage 1 is the initial period leading to cutoff vulnerability, stage 2 is the actual cutoff, and stage 3 is the morphological adjustment in response to the cutoff. In stage 1, a plug bar was deposited in one of the channel bends. Hydrodynamic model results show the location of the plug bar coincides with a region where bed shear stress decreased in downstream direction due to backwater. Longitudinal channel bed profiles show that the channel slope decreased soon after channel reconstruction. Hence, sediment from upstream was available to form the plug bar. After the plug bar was deposited, an embayment formed in the floodplain at a location where the former channel was located (stage 2). The former channel was filled with sediment prior to channel construction. It is likely that the sediment at this location was less consolidated, and therefore, prone to erosion. The chute channel continued to incise and widen into the floodplain and, after 6 months, acted as the main channel, conveying the discharge during the majority of time (stage 3). The cutoff channel gradually continued to fill with sediment, from the moment the plug bar formed until the chute channel incised into the floodplain. Sedimentary successions of the deposited material show upward fining, which is in agreement with observations of chute cutoffs in rivers. Although the artificial setting limits the degree in which the observed processes can be projected on natural rivers, the observations prompt to investigate the role of backwater effects in natural chute cutoff initiation.
Myocardial Characterization for Early Diagnosis, Treatment Response Monitoring, and Risk Assessment in Systemic Light-Chain Amyloidosis

Aims: In systemic light-chain (AL) amyloidosis, cardiac involvement portends poor prognosis. Using myocardial characteristics on magnetic resonance imaging (MRI), this study aimed to detect early myocardial alterations, to analyze temporal changes with plasma cell therapy, and to predict risk of major adverse cardiac events (MACE) in AL amyloidosis. Methods and Results: Participants with recently diagnosed AL amyloidosis were prospectively enrolled. Presence of AL cardiomyopathy (AL-CMP vs. AL-non-CMP) was determined by abnormal cardiac biomarkers. MRI was performed at baseline and 6 months, with 12-month imaging in AL-CMP cohort. MACE was defined as all-cause death, heart failure hospitalization, or cardiac transplantation. Mayo AL stage was based on troponin T, NT-proBNP, and difference in free light chains. The study cohort included 80 participants (median age 62 years, 58% males). Median left ventricular extracellular volume (ECV) was significantly higher in AL-CMP (53% vs. 30%, p<0.001). ECV was abnormal (>32%) in all AL-CMP and in 47% of AL-non-CMP. ECV tended to increase at 6 months and decreased significantly from 6 to 12 months in AL-CMP (median -3%, p=0.011). ECV was strongly associated with MACE (p<0.001), and improved MACE prediction when added to Mayo AL stage (p=0.002). ECV[≤]32% identified a cohort without MACE, while ECV>48% identified a cohort with 74% MACE. Conclusions: In AL amyloidosis, ECV detects subclinical cardiomyopathy. ECV tends to increase from baseline to 6 months and decreases significantly from 6 and 12 months of plasma cell therapy in AL-CMP. ECV provides excellent risk stratification and offers additional prognostic performance over Mayo AL stage.
A LAND-COVER DATA INFRASTRUCTURE FOR MEASUREMENT, MODELING, AND ANALYSIS OF LAND-COVER CHANGE DYNAMICS

This paper presents a land cover data infrastructure that integrates multiple data sources, analytical methods and land-cover data products to support basic and applied research on land-cover dynamics. The infrastructure is appropriate for description, management, analysis and modeling of land-cover change dynamics. The infrastructure design produces an integrated suite of databases and toolboxes that support the entire processing stream. The data needs of the applications of land-cover data are the primary focus rather than the representation of a cartographic land-cover product. The infrastructure integrates diverse data sources, including imagery, field data and existing land-cover maps with data processing operations; the goal is to provide data for modeling and analysis of land-cover dynamics relevant to application needs of different users. This infrastructure has been implemented using digital orthophotographs, Landsat images and a comprehensive geographic information system database.
Sensitivity of the African Neuropsychology Battery Memory Subtests and Learning Slopes in Discriminating APOE 4 and Amyloid Pathology in Adult Individuals in the Democratic Republic of Congo

Background: The current study examined the sensitivity of two memory subtests and their corresponding learning slope metrics derived from the African Neuropsychology Battery (ANB) to detect amyloid pathology and APOE4 status in adults from Kinshasa, the Democratic Republic of the Congo. Methods: 85 participants were classified for the presence of {beta}-amyloid pathology and based on allelic presence of APOE4. All participants were screened using CSID and AQ, underwent verbal and visuospatial memory testing from ANB, and provided blood samples for plasma A{beta}42, A{beta}40, and APOE proteotype. Pearson correlation, linear and logistic regression were conducted to compare amyloid pathology and APOE4 status with derived learning scores, including initial learning, raw learning score, learning over trials, and learning ratio. Results: Our sample included 35 amyloid positive and 44 amyloid negative individuals as well as 42 without and 39 with APOE4. All ROC AUC ranges for the prediction of amyloid pathology based on learning scores were low, ranging between 0.56-0.70 (95% CI ranging from 0.44-0.82). The sensitivity of all the scores ranged between 54.3-88.6, with some learning metrics demonstrating good sensitivity. Regarding APOE4 prediction, all AUC values ranged between 0.60-0.69, with all sensitivity measures ranging between 53.8-89.7. There were minimal differences in the AUC values across learning slope metrics, largely due to the lack of ceiling effects in this sample. Discussion: This study demonstrates that some ANB memory subtests and learning slope metrics can discriminate those that are normal from those with amyloid pathology and those with and without APOE4, consistent with findings reported in Western populations.
A Mathematical Model Simulating the Adaptive Immune Response in Various Vaccines and Vaccination Strategies

Vaccination is the most effective measure for preventing infectious diseases. Developing an appropriate mathematical model facilitates quantitative research into the activation of adaptive immune responses in the human body by vaccines, thereby providing better guidance for vaccine development. In this study, we have constructed a novel mathematical model to simulate the dynamics of antibody levels following vaccination. Based on principles from immunology, our model provides a concise and accurate representation of the kinetics of antibody response. We have compared the antibody dynamics within the body after administering several common vaccines, including traditional inactivated vaccines, mRNA vaccines, and future attenuated vaccines based on defective interfering viral particles (DVG). Our model explains the crucial role of booster shots in enhancing IgG antibody levels and provides a detailed discussion on the advantages and disadvantages of different vaccine types. From a mathematical standpoint, our model systematically proposes four essential approaches to guide vaccine design: enhancing antigenic T-cell immunogenicity, directing the production of high-affinity antibodies, reducing the rate of IgG decay, and lowering the peak level of vaccine antigen-antibody complexes. Our model contributes to the understanding of vaccine design and its application by explaining various phenomena and providing positive guidance in comprehending the interactions between antibodies and antigenic substances during the immune process.
Prognostic factors influencing HIV-free survival among infants enrolled for HIV early infant diagnosis services in selected hospitals in Nairobi County, Kenya

Background Despite being a preventable disease, pediatric HIV infection continues to be a public health concern due to the morbidity and mortality associated with the disease. Vertical transmission of HIV occurs when a mother living with HIV passes the virus to her baby during pregnancy, childbirth, or breastfeeding. Globally, the vertical transmission rate of HIV is 9% with sub-Saharan Africa accounting for 90% of these infections. In Kenya, the national vertical transmission rates of HIV stood at 11.5% by the end of 2018, with a target to reduce vertical transmission rates to below 5% and 2% in breastfeeding and non-breastfeeding infants respectively, by the end of 2021. Objective To determine the prognostic factors influencing HIV-free survival among infants enrolled for HIV early infant diagnosis (EID) services in selected hospitals in Nairobi County, Kenya. Methods A prospective cohort study design was adopted. HIV exposed infants were recruited at six weeks to determine HIV-free survival over 12 months follow up. Simple random sampling was used to select 166 infants and data were collected from the mothers using semi-structured interviewer-administered questionnaires. Log-rank tests were used to test for associations at the bi-variable level while Cox-proportional regression was used to analyze data at the multi-variable level, with the aid of STATA 14 software. Ethical approval was obtained from Kenya Medical Research Institute, Scientific Ethics Review Unit. Results The overall infant HIV incidence rate over one-year follow-up was 9 cases per 100 person-years (95% CI: 5.465–16.290). The failure event was defined as an infant with a positive PCR test during the study period with total failures being 13 (9.41%) over 12 months. Prognostic factors associated with poor infant HIV-free survival were young maternal age (18–24 years) and mothers with a recent HIV diagnosis of ≤ 2 years since a positive HIV diagnosis (HR 5.97 CI: 1.20, 29.58) and (HR 6.97 CI: 1.96, 24.76), respectively. Conclusion Maternal prognostic factors associated with poor infant HIV-free survival were young maternal age (18–24 years) and recent maternal HIV diagnosis of ≤ 2 years since positive HIV diagnosis. The study recommended the development of an intervention package with more rigorous adherence counseling and close monitoring for young mothers, and mothers with recent HIV diagnoses.
Early rifting of an oceanic island arc (Fiji) produced shoshonitic to tholeiitic basalts

Shoshonitic volcanism began in Fiji within 50 km of and 0.5 m.y. after formation of a transverse rift which broke the oceanic Vitiaz Arc across strike. Shoshonitic basalts erupted from 10 volcanoes along three lineaments for up to 225 km away from the rift along strike, from 5.5 to 3.0 Ma, during Fiji's “incipient rifting stage. ” Three shoshonitic suites are distinguished based on differentiation-normalized alkali contents, but K-Rb-Ba-Sr, P-rare earth element (REE), and Ti-Zr-Hf enrichments occur independent of each other. Enrichments are extremes of typical arc geochemical signatures, and are superimposed on high field strength elements and HREE concentrations and ratios like those of arc tholeiites. Medium- and high-K calcalkaline volcanics are interspersed with shoshonites. Still farther from the transverse rift, coeval tholeiitic basalts erupted along the volcanic front. Decreasing large ion lithophile element enrichments from shoshonitic through calcalkaline to tholeiitic are attributed to increased percent fusion away from the transverse rift. All three suites are basalt-dominated despite thickened crust, due to regional tension associated with fragmentation of the oceanic arc.