Thick Interval Research Articles

Basin-scale exhumed Cretaceous fluvial systems (Chubut Group, Cañadón Asfalto basin), central Patagonia, Argentina

This contribution describes basin-scale, Cretaceous (Late Aptian to Cenomanian-Early Turonian) fluvial systems outcropped over ∼30,000 km2 that contain more than 7000 exhumed paleochannels in the Chubut Group, Cañadón Asfalto basin (central Patagonia), Argentina. Paleochannels are encased within a ∼350 m thick stratigraphic interval (∼20 My) including volcaniclastic and epiclastic fluvial units (Cerro Barcino and Puesto Manuel Arce formations). Geomorphologically, the exhumed paleochannels conform to isolated sandstones/conglomeratic ridges, a swarm of paleochannels, and elongated/equidimensional mesas (plateaus), characterizing much of the “mesetiform” landscape in central Chubut. The plan-view analysis of exhumed paleochannels mainly shows a mean WNW-ESE orientation (112°–292°) and predominance of narrow (83.1%) and very narrow (14.4%), low-sinuosity channels (96%). A plan-view multi-scale architectural analysis of sandbodies allows us to recognize different fluvial hierarchies: a) 3rd-order lithosomes (macroform growth increments), b) 4th-order lithosomes (point bars and crevasse-channels), b) 5th-order lithosomes (main channels), and c) 6th-order lithosomes (channel belts). Two main types of channel arrangements in the exhumed fluvial systems were recognized: fixed-channel and mobile channel belts. We observed a broad relationship between geomorphologic configurations and fluvial architectural units. Some macro spatiotemporal variation in the fluvial architecture was observed towards the youngest positions, including wider channels and a greater relative abundance of high-sinuosity channels with point bars. The basin-scale distribution of exhumed paleochannels would allow us to infer the predominance of shallow lacustrine or lagoon deposits in the western basin region, probably controlled by the inherited topography of the Jurassic- Early Cretaceous depocenters.

Aflibercept for central retinal vein occlusions: long-term outcomes of a ‘Treat-and-Extend’ regimen

Background/aimsThis study reports on the long-term functional and anatomical outcomes of patients with central retinal vein occlusion (CRVO) treated under the Bern treat-and-extend (T&E) protocol.MethodsObservational study. Treatment-naive patients with CRVO...

Paleoenvironmental factors controlling organic-rich formations deposition in the Babouri-Figuil Basin (Northern Cameroon)

The Babouri-Figuil Basin is an intracratonic basin (half-graben) in northern Cameroon that is genetically connected to the Benue Trough from Nigeria, and is an area of interest in terms of petroleum prospectivity. Recent studies highlighted the presence of organic-rich formations in the basin. However, none of these works have identified factors that governed the accumulation of organic matter (OM) in the sediments. The main objective of this work is the characterization of these formations through palynofacies and organic geochemical techniques (total organic carbon - TOC, total sulfur, insoluble residue and biomarkers), in order to determine the organic facies, their depositional environments and the main drivers for organic enrichment in the basin. The current study reveals that black shale and massive claystone lithologies constitute the main organic-rich formations in the basin, with TOC reaching up to 26.08 wt%, being characterized by a dominance of bacterially-derived amorphous OM. Palynofacies and biomarker data revealed that these formations are positively associated with anoxic conditions and a partly highly saline and stratified lake water column. The deposition of organic-rich formations in the Babouri-Figuil Basin was mainly controlled by restriction conditions which developed in connection with the regional tectonic framework. The Lower Cretaceous rifting episode in the West and Central African Rift System (WCARS) basins led to the formation of accommodation space, a reduction in water levels, and the development of anoxic conditions within the basin, facilitating the deposition of organic-rich formations. Therefore, the organic enrichment of the Babouri-Figuil Basin has been predominantly controlled by its tectonic evolution, particularly during the syn-rift phase. This phase created favorable conditions for the deposition and preservation of OM, including the establishment of anoxic conditions. Additionally, the paleoclimate (arid conditions), the development of bacterial biomass, and the basin's paleogeography all played a significant role in this process. The organic-rich formations of the Babouri-Figuil Basin show characteristics of prospective petroleum source rocks (high organic content, high proportion of oil-prone kerogen, significant thickness and lateral extension). The combination of organic-rich formations with sandstone deposits above and extensive claystone/shale deposits on top can indicate the presence of an oil play in the basin. A detailed study with broader sampling is needed to investigate thoroughly the variation of organic facies and the influence of paleoenvironmental factors that control the deposition of thick source rock intervals.

Repeatability and reproducibility of deep learning features for lung adenocarcinoma subtypes with nodules less than 10 mm in size: a multicenter thin-slice computed tomography phantom and clinical validation study.

Deep learning features (DLFs) derived from radiomics features (RFs) fused with deep learning have shown potential in enhancing diagnostic capability. However, the limited repeatability and reproducibility of DLFs across multiple centers represents a challenge in the clinically validation of these features. This study thus aimed to evaluate the repeatability and reproducibility of DLFs and their potential efficiency in differentiating subtypes of lung adenocarcinoma less than 10 mm in size and manifesting as ground-glass nodules (GGNs). A chest phantom with nodules was scanned repeatedly using different thin-slice computed tomography (TSCT) scanners with varying acquisition and reconstruction parameters. The robustness of the DLFs was measured using the concordance correlation coefficient (CCC) and intraclass correlation coefficient (ICC). A deep learning approach was used for visualizing the DLFs. To assess the clinical effectiveness and generalizability of the stable and informative DLFs, three hospitals were used to source 275 patients, in whom 405 nodules were pathologically differentially diagnosed as GGN lung adenocarcinoma less than 10 mm in size and were retrospectively reviewed for clinical validation. A total of 64 DLFs were analyzed, which revealed that the variables of slice thickness and slice interval (ICC, 0.79±0.18) and reconstruction kernel (ICC, 0.82±0.07) were significantly associated with the robustness of DLFs. Feature visualization showed that the DLFs were mainly focused around the nodule areas. In the external validation, a subset of 28 robust DLFs identified as stable under all sources of variability achieved the highest area under curve [AUC =0.65, 95% confidence interval (CI): 0.53-0.76] compared to other DLF models and the radiomics model. Although different manufacturers and scanning schemes affect the reproducibility of DLFs, certain DLFs demonstrated excellent stability and effectively improved diagnostic the efficacy for identifying subtypes of lung adenocarcinoma. Therefore, as the first step, screening stable DLFs in multicenter DLFs research may improve diagnostic efficacy and promote the application of these features.

Dolomite occurrence within drift deposits, Maldives archipelago

Considerable attention has been dedicated to the sedimentological processes associated with carbonate drift and contourite deposits, but a noticeable gap exists in the understanding of the diagenetic aspects of those deposits, especially dolomitization. This study presents an examination of dolomites from Middle to Late Miocene drift deposits collected during IODP Expedition 359 to the Maldives archipelago. Multiple geochemical parameters and petrographic analysis are used to explore the potential role of closed versus open system dolomitization in the two oldest drift sequences, which are overlain by a multimillion year-long hiatus. Overall, dolomite abundance is variable, but 50 % to nearly 100 % in a 30 m thick interval below the unconformity surface at one of the examined sites. The dolomite in the study interval consists of very fine-to-fine-sized crystalline dolomite cements and mimetically replaced dolomite grains. All dolomite is non-stoichiometric (mean 42.7 ± 2.0 mol% MgCO3) and mostly poorly ordered. Geochemical attributes include relatively invariant δ13C (+1.3 ‰ to +1.7 ‰ VPDB) and relatively high Sr concentrations in dolomite cements (mean 505 ppm) and dolomitized grains (mean 784 ppm). δ18O values and the constraints of burial histories indicate dolomitization in normal marine seawater at burial depths of 0 to 300 m and temperatures of ∼10 °C–14 °C below an ocean water column 100 to 400 m deep. Sr-isotope ages suggest dolomitization of the most extensively dolomitized interval below the unconformity occurred between 12.3 Ma and 6.7 Ma. Overall, the geochemical data and previously published δ34SCAS data suggest a closed, diffusion-dominated system created most of the dolomite. However, the youngest dolomite's age and bulk rock Sr isotope ages of calcitic rocks at the base of the drift deposits can only be explained by the advective flux of seawater through all the drift deposits. Furthermore, the geological context, including permeable facies, ocean current patterns, and other indicators, such as the absence of hardground or permeability barriers, suggests that some open system dolomitization may have also occurred.

The Miocene lacustrine carbonate factory of the Ñirihuau Formation, Ñirihuau Basin, North Patagonian Andes, Argentina

AbstractFacies, microfacies and stable isotope analyses of limestone beds in the northernmost Ñirihuau Basin, North Patagonian Andes, Argentina, document and constrain the past hydrological, sedimentological and climate conditions that prevailed during the deposition of a lacustrine system between ca 15 and 13 Ma. This palaeoenvironment is recorded in the middle section of the Ñirihuau Formation, which holds significance because: (1) It was deposited during a transition from an extensional to a compressional tectonic regime; (2) it spans the Middle Miocene Climatic Optimum and the beginning of the Middle Miocene Climatic Transition; and (3) it contains limestone beds interbedded within a 600 m thick interval of mudstones and siltstones, along with intercalated sandstone and volcaniclastic bodies. Two detailed sedimentary logs were surveyed along the Arroyo Las Bayas, at the western and eastern flank of the David Syncline. Limestones from both stratigraphic sections were sampled as well as isolated limestone beds from two other sites. One facies association was defined and interpreted as a perennial lake associated with a deltaic system and dominated by detrital clastic material. It comprises Facies 1 (Marginal lacustrine) and Facies 2 (Lower delta plain); in both, the presence of grainstones and calcimudstones stands out. Through petrography and cathodoluminescence studies of these continental carbonates, nine microfacies were identified: (a) Intraclastic grainstone, (b) Homogeneous calcimudstone, (c) Silty grainstone, (d) Disrupted micrite, (e) Birds eye micrite, (f) Bioclastic mudstone, (g) Calcimudstone with sparse detrital grains, (h) Fenestral micrite, (i) Stromatolitic boundstone. These indicate mainly bio‐induced subaqueous carbonate precipitation and subordinate deposition by tractive flows with short‐distance transport on a littoral lacustrine environment. Most of these microfacies exhibit very early diagenesis (eogenesis) effects. These features, and the geochemistry results, indicate that they were deposited in a palaeolake system under temperate to warm and humid conditions.

Research on failure characteristics and mechanism of ZK61m magnesium alloy plate under the impact of ogival projectile

To study the influence of the thickness effect on the impact performance of ZK61m magnesium alloy plate, the influence of ogival projectile on the impact performance of magnesium alloy plate of different thicknesses is analyzed through experiments and numerical simulations, the ballistic limits and failure modes of different thicknesses of the punch target plate are obtained. The velocity of the plug is analyzed by introducing the extruded chisel block velocity model. The experimental results show that the ballistic limit value of the target plate in a specific thickness interval (7 ∼ 11 mm) increases slowly with the increase of its thickness, and the failure mode is dominated by the shear punching failure and accompanied by the tensile failure. The plugs formed in the experimental process are consistent with the extruded chisel block velocity model. Numerical simulation results show that the MJC fracture criterion predictions deviate from the experimental results due to the overestimation of the material ductility, while the Lode parameter dependent MMC fracture criterion, which can better predict the ballistic behavior and failure modes of the target plate.

Supplementing Monosodium Glutamate in Sow Diets Enhances Reproductive Performance in Lactating Sows and Improves the Growth of Suckling Piglets.

In most current farm operations, lactating sows need to overcome reproductive and environmental stresses that have resulted in poor sow production performance and piglet growth. Therefore, this study aimed to investigate the effects of in-feed supplementation of monosodium glutamate (MSG) in sows during late gestation lactation in regard to litter performance. The study subjects were 12 multi-parity sows (Landrace × Large White), farrowing sows with an average parity of four (three with three parities, seven with four parities, and two with five parities). They were randomly divided into the following two diet groups: the basal diet as a control (CON) group based on corn and soybean meal; and the basal diet + 2% MSG group. The experimental time ranged from 109 days before delivery to 21 days after delivery. There were six sows in each group, and each sow served as the experimental unit. There were no significant differences (p > 0.05) in body weight (BW), back fat (BF) thickness and estrus interval between sows supplemented with 2% MSG in their diets before and after farrowing and during weaning (p > 0.05). However, MSG-treated sows tended to increase BW loss at farrowing more than the CON group (p = 0.093) but lost less weight during lactation than the CON group (p = 0.019). There were no significant differences in the body condition scores (BCSs) and BF loss of the two groups of sows before and after farrowing and at weaning (p > 0.05). There was no significant difference in the weight of newborn piglets between the two groups of sows (p > 0.05). The weaning weight (p = 0.020) and average daily gain (ADG) (p = 0.045) of suckling piglets were higher in the MSG treated group compared to the CON group. The daily milk production of sows in the MSG treatment group was higher compared to the CON group (p = 0.045). The protein concentration of milk at week 3 (p = 0.060) and fat concentration of milk at week 5 (p = 0.095) of the MSG-supplemented sows tended to increase more than the CON group. In summary, the dietary inclusion of MSG supplementation had a beneficial effect on the late gestating sows and their piglet's growth and milk production. Our research has shown that the addition of 2% MSG in late gestation and lactation diet would be beneficial for both sow and piglet production.

#2647 Assessing atherosclerosis using epicardial adipose tissue in hemodialysis patients: a meta-analysis

Abstract Background and Aims Hemodialysis (HD) patients had higher cardiovascular mortality due to accelerated atherosclerosis in such patients. Epicardial adipose tissue (EAT) thickness is a marker of atherosclerosis and independent predictor of coronary artery disease. The potential use of EAT as an imaging biomarker for cardiovascular disease risk stratification has attracted attention in the recent times. EAT's value in cases of HD hasn't been thoroughly analyzed, though. A meta-analysis of the literature assessing the mean differences in EAT value between HD patients and healthy controls was conducted. Method Pubmed, Google Scholar and Embase databases were searched from inception till 15 January 2024 for studies that measured EAT thickness of adult patients with HD and matched healthy controls. Outcomes included mean difference (MD) and 95% confidence interval (CI) of EAT thickness between the HD patients and the healthy controls. The results were combined using a fixed or random effect model as per heterogeneity among the included studies in Revman 5.4 software. The between-study heterogeneity of effect size was quantified using the Q statistic and I2. The results were represented in forest plots. Statistical significance was determined as P value of less than 0.05. Results Eight studies comprising 757 patients were included in this analysis. EAT thickness were significantly higher in HD patients as compared to healthy controls [MD: 1.88, Confidence Interval (CI): 0.74-3.02, I2 = 98%, P value = 0.001] (Fig. 1). Conclusion This meta-analysis concluded that HD patients are independently associated with higher EAT as compared to healthy controls. The utility of EAT as an imaging biomarker for predicting atherosclerosis in HD patients is promising. EAT represent readily available clinical markers useful in estimating risk of cardiovascular mortality in HD patients.

An integrated stratigraphic re-evaluation of key Central Atlantic DSDP sites

Re-sampling and new analysis of DSDP core from key Central Atlantic sites, drilled over 30 years ago, has allowed an updated stratigraphic framework to be developed. This study refines the timing and nature of key unconformities that have previously been documented to occur elsewhere in the oceanic domain of the Central Atlantic during the drilling of many DSDP legs. Biostratigraphic dating using calcareous nannofossils and palynology has been performed on 168 samples. This higher biostratigraphic resolution improves regional correlation and has allowed identification of major hiati previously unrecognised within the oceanic domain stratigraphy.This work builds on the pioneering work of the DSDP cruises, and utilises the valuable data collected for new age dating, supplemented with new organic geochemistry analysis and sedimentological characterisation to improve documentation of the Mesozoic strata. Results are extrapolated along the continental margin of northwest Africa and the conjugate in South America, using regional two-dimensional seismic sections, providing a correlation between the oceanic domain stratigraphy and shelfal depositional systems penetrated by hydrocarbon exploration wells.At DSDP Site 367, a middle Berriasian unconformity is recognised for the first time in Core 33, where middle Berriasian white pelagic limestones (Blake-Bahama Formation) sit unconformably on Early Tithonian red argillaceous limestones (Cat Gap Formation). Faunal dating indicates a ca. 5 Myr hiatus at the Jurassic-Cretaceous boundary. Marl interbeds within the pelagic limestones increase in occurrence through the Barremian, reflecting increased terrigenous input, with associated total organic content (TOC) averaging 5%.A second major lithological break is identified at DSDP Site 367, interpreted as a base Albian unconformity, between the Blake-Bahama and overlying Hatteras Formations. Sediments above are intra late Albian variegated claystones with abundant terrestrial detritus and distal turbidites. Seismic data that intersects the well location show onlapping reflections of early-middle Albian strata landward of DSDP Site 367, indicating paleo-topography prior to Albian deposition. These sediments are contemporaneous with a major progradational phase on the shelf and a sedimentary wedge observed at the base of the carbonate escarpment. Early Albian sediments sit above the interpreted base Albian unconformity at DSDP Site 534 A on the conjugate US Atlantic margin, suggesting the super-regional nature of this event. The refined dating provides age calibration of a basin-wide unconformity, previously known from seismo-stratigraphic studies as Reflector β.In addition to the revised stratigraphic framework, evidence is presented for the occurrence of seaward dipping reflectors (SDRs) northwest of the Guinea Plateau. SDRs have not been reported along this section of the African margin, demonstrating volcanic addition during early seafloor spreading and extending the occurrence of volcanics associated with the African Blake Spur magnetic anomaly further south beyond the Cap Vert fracture zone previously mapped. At DSDP Site 368 we also note that the late Albian to late Cenomanian strata (Hatteras Formation) is composed of a 164 m thick organic-rich interval, containing up to 37% TOC, with facies and organic geochemical heterogeneity. This transgressive sequence is associated with a flooding of the shelf.This revised stratigraphic framework provides a solid foundation for future Central Atlantic studies intending to use these sites as calibration of the oceanic domain stratigraphy.

Geochemical Modeling and Hydrocarbon Generation Potentiality of Source Rocks of the Oligocene to Miocene Succession in the Temsah Area, Eastern Nile Delta, Egypt

Geochemical investigation of the Temsah-4 well (T-4) in Temsah gas fields at the eastern offshore Nile Delta differentiate into two categories of OM (organic matter) which are kerogen types II and III within the boreholes penetrated Oligocene-Miocene source rocks. The geochemical and lithological characteristics of the OM-bearing formations in the investigated borehole recognized four thick organic matter-rich intervals (OMRI) in well T-4. The OMRI considers a part of formations that are believed to be considered a real source rock that comprises approximately 66.68% of the Wakar, 65.17% of Sidi-Salem, and 100% of Qantara Fms in the T-4 well. They comprised intervals depths of 3120m-3150m and 3300m-3559.4m belonging to Wakar Fm, from 3580m- 3870m belonging to Sidi-Salem Fm and from 3977m- 4170m belonging to Qantara Fm. The geochemical data reveals that Wakar Fm in the T-4 well considers immature source rock. While mature OMRI within Sidi-Salem and Qantara Fms in the T-4 well represented as effective mature source rocks. Construction of a TOC map in two dimensions throughout the studied areas shows a trend of increasing the quantity of OM eastward during the deposition of Sidi-Salem and Wakar Fms. The improvements of the richness (relatively high TOC) toward the eastward suggested a favorable condition for preservation and accumulation of OM toward the east than the west drilled boreholes. Based on the relative hydrocarbon potential (RHP) the suggested expulsion threshold depths appear to be shallower at 3700m in T-4. Burial history diagrams of studied T-4 wells based on geochemical results postulate that Tineh Fm enters the early mature stage at 2.8Ma. The maturity continues till the recent periods to enter the Qantara and most of Sidi-Salem Fms the same main-oil window at the T-4 area.

Untangling the biotic stress in the late Maastrichtian Deccan-benchmark interval of Bidart (France)

The late Maastrichtian witnessed substantial surges in Deccan volcanism, prompting the hypothesis that these voluminous pulses may have instigated repeated episodes of ocean acidification during this period. The Cretaceous-Palaeogene (K/Pg) boundary at Bidart (France) is preceded by a ∼0.5 m thick interval with geochemical and taphonomic vestiges of an ocean acidification event linked with Deccan volcanism. New planktic foraminifera census and morphometric data now confirm biotic stress conditions related to acidification in the Deccan benchmark interval. The absolute abundance data of larger (>150 μm) heavily calcified planktic morphogroups show fluctuating populations throughout zone CF1 (spanning the final ∼225 ky), lowest peaks within the Deccan benchmark, and a demographic collapse (>90%) at the K/Pg boundary. The analyzed species are generally reduced in size, with thinner test walls in this ∼0.5 m interval, indicating the likelihood of calcification stress as a contributor to the overall biotic stress. At the K/Pg boundary, maximum biotic stress is recorded in all the tested faunal proxies. A preliminary graphic correlation of zone CF1 at Bidart with the auxiliary GSSP at Elles (Tunisia) constrains the Deccan benchmark interval of high biotic stress to the final ∼58 ky of the late Maastrichtian, culminating in the K/Pg mass extinction. The volcanogenic Hg peaks coincident with faunal and taphonomic evidence of ocean acidification strengthen the Deccan-related ocean acidification hypothesis.

Crater radius analysis after dual droplets successive oblique impact on liquid film

Droplet impact is a common occurrence in nature, agriculture, and industry. The research on the multi‐droplet impact is fundamental to understanding the tangled nature of reality. This paper numerically studies the successive oblique impact of dual droplets on the liquid film by building an effective three‐dimensional model. The leading and trailing droplets are set to pass a certain impact point with the same velocity. The main contribution of this paper is the investigation of the effects of Weber number, liquid film thickness, impact angle, and impact time interval on the interface morphology evolution after the droplet impact. Results show that splash pattern conversion of the primary or secondary crown occurs with the change of these factors. Besides, the variations of the maximum crater radius in upstream, lateral, and downstream directions with time are quantitatively analyzed. The crater radius analysis is carried out from three perspectives, the variation during the single droplet impact, the change during the dual droplets impact, and the comparison between them. It is found that the crater of dual droplets impact exhibits shape distortion in the deformation period and appears a marked dimensional increase in the secondary expansion period.

Five-year changes in macular thickness in the elderly population: A cohort study.

The aim of this study is to determine the 5-year changes in macular thickness and related factors. Data were from the second (2014) and third (2019) phases of the Shahroud Eye Cohort Study. Examinations included measurement of uncorrected and best-corrected visual acuity, non-cycloplegic autorefraction, slit-lamp biomicroscopy, and funduscopy. Participants underwent Cirrus HD-OCT 4000 (Carl Zeiss Meditec, Dublin, CA). The 5-year changes (95% confidence interval) of central and overall macular thicknesses were - 3.48 ± 8.16 μ (-3.92, -3.03) and - 0.79 ± 4.06 μ (-1.03, -0.54), respectively. The median and IQR of 5-year changes in the central subfield thickness were -3 and 10, although they were 0 and 5 in the overall macular thickness, respectively. Multiple regression model showed the central macular thickness (CMT) decreased with a U-shape pattern with increasing age. The 5-year changes in CMT were significantly lower in females compared to males β = -1.55; (-2.78, -0.32) and in smokers compared to non-smokers β = -1.92; (-3.55, -0.28). Moreover, higher body mass index β = -0.12; (-0.22, -0.02) and CMT at baseline β = -0.08; (-0.10, -0.06) were significantly associated with lower CMT changes. The average 5-year changes in overall macular thickness showed a non-linear decrease with age and was significantly higher in females β = 0.93; (0.4, 1.43). These changes were directly related to the anterior chamber depth β = 0.87; (0.10, 1.64) in the baseline. The macular thickness decreased slightly after 5 years; however, this change is not clinically significant. Demographic factors such as age and sex and refractive errors were significantly related to macular thickness changes.

Hydrostratigraphic decomposition of fluvio-deltaic sediments inferred from seismic geomorphology and geophysical well logs in the Pannonian Basin, Hungary

Heterogeneity and anisotropy of lithological units influences hydraulic conductivity on several scales. The purpose of this study is to develop a novel method supporting hydrostratigraphic classification by considering horizontal and vertical variations of sand content in relation with the paleo-depositional environment. The workflow was applied for the uppermost ca. 1800 m thick fluvio-deltaic deposits (Great Plain Aquifer) of late Neogene to Quaternary age basin-fill succession in the eastern part of the Pannonian basin in Hungary. Five combined 3D seismic volumes, seven master horizons, and 30 well logs were analyzed. First, RMS amplitude maps were extracted to interpret the seismic geomorphological features and depositional architectures. Their associated lithology was inferred from wireline logs (GR and SP) by calculating the shale volume and the net-to-gross sand ratio for 30 m thick intervals. These were used to calibrate the seismic facies as a proxy for the horizontal distribution of sand versus shale. This method allowed the identification of sand bodies, i.e.: deltaic lobes, complex channel belts, simple fluvial channels behaving as aquifers, and the dominantly muddy delta plain to flood plain suits as aquitard. The vertical pattern of sand distribution was also evaluated. Three major stratiform and some corridor-like minor hydrostratigraphic units were defined instead of the former regional (basin) scale aquifer unit. 1) Laterally extended interval of stacked deltaic lobes of high sand ratios and high rate of connectedness, at the bottom of the studied interval. 2) General presence of extended muddy floodplains with anastomosing river systems, characterized by 100–200 m wide channels, low sand ratio, and limited connectedness: 3) widespread meandering and/or braided river systems with high sand ratios and high connectedness in the Quaternary. Within unit 2) spatially and temporally variable appearance of major 500–3600 m wide meandering channel belts produce locally high sand-ratio corridors in the NE-SW direction. A workflow adapted from the oil-and-gas industry was successfully applied to distinguish units of varying sand content and hydraulic conductivity. This approach can be used on basin to local scale to build a spatially complex facies-based model of hydrostratigraphy. Thus, a robust heterogeneous geological model serves as a base for investigating fluid flow on the required scale.

The effect of electrical parameters of eddy current sensor on metal film thickness measurement performance and the optimization method.

Eddy current sensors have been widely used in the field of micro- and nano-measurements. The detection circuit is a key part of eddy current sensors. In particular, the electrical parameters in the signal conversion circuit have an important effect on the measurement performance. It is necessary to study the effect of the electrical parameters on the measurement performance and propose an optimization method. In this study, a simulation model of the eddy current sensor is established by coupling a magnetic field and a circuit field. The circuits include the LC parallel resonance, the AC bridge, and three combination circuits of the LC resonant and AC bridge. The output voltage variation with the thickness of copper film is calculated, and the effect of the electrical parameters on sensitivity Ki is obtained. In the LC parallel resonant circuit, it' is revealed that K1 is maximum when the parallel capacitance CP is equal to the resonant capacitance C0. An optimization method of adjusting resistance RS in different thickness intervals is proposed. In the AC bridge circuit, it' is revealed that there exists an optimal RS, which makes K2 maximum. In three combination circuits, K3, K4, and K5 are the maximum when the capacitances (C1, C2, and C3) reach the resonant capacitance C0. In addition, the sensitivity of each combination circuit is improved compared with that of the AC bridge. The relevant analysis results are further verified by a series of experiments. According to the calculation results and the experimental analysis, the optimization method for electrical parameters is further proposed.

Macular Thickness and Volume by Spectral-Domain Optical Coherence Tomography and their Related Factors in the Elderly Population.

To determine the distribution of macular thickness and macular volume in an elderly healthy population 60 years of age and above and their determinants. The sampling was performed using a multistage stratified random cluster sampling method on the geriatric population 60 years of age and above in Tehran, Iran. All participants underwent optometric examinations, slit-lamp examination, and optical biometry. Retinal imaging was performed by spectral-domain optical coherence tomography. The means ± standard deviation and 95% confidence interval of central macular thickness (CMT), average macular thickness (AMT), and macular volume were 221 ± 33 (218-223) μm, 267 ± 29 (265-269) μm, and 8.36 ± 0.44 (8.33-8.39) mm3, respectively. The CMT was significantly lower in females than males (β: -5.77; P = 0.002). The AMT was significantly lower in females than males (β = -10.32; P < 0.001) and was significantly directly related to intraocular pressure (β = 0.63; P = 0.038). The macular volume was significantly lower in females than males (β = -0.13; P < 0.001) and decreased with age (β = -0.01; P < 0.001). In addition, the macular volume had a significant inverse and direct relationship with axial length (β = -0.04; P = 0.011) and keratometry (β = 0.03; P < 0.001). Macular thickness in the Iranian geriatric population was slightly less than the populations studied in other countries. The role of sex should also be taken into account in the interpretation of macular thickness findings.

FIRST RESULTS OF STRATIGRAPHIC DRILLING IN THE EAST SIBERIAN SEA FOCUSED ON THE GEOLOGICAL STUDIES OF THE SUTURE ZONE OF THE CONTINENTAL SHELF’S MARGINAL STRUCTURES A ND DEEP-WATER AREAS OF THE ARCTIC OCEAN

At the initiative of the Federal Agency on Mineral Resources (Rosnedra), in August 2022, a shallow well was drilled in the East Siberian Sea for the first time with a purpose of geological studying the suture zone of deep waters of the Arctic Ocean and marginal structures of the continental shelf. The well was drilled by VSEGEI and Rosgeologia with the assistance of NK Rosneft and linked to the Rosneft’s long-term stratigraphic drilling program. Drilling was accompanied by continuous seismoacoustic profiling and well thermometry. The maximum well depth was 472 m from the bottom surface; in it, 147.5 m of core was taken to a depth of 268 m. Two sedimentary sequences were identified in the section: the lower Jurassic-Lower Cretaceous gently deformed sequence and the upper Neogene-Quaternary horizontally lying sequence. The sequences are separated by a thick unsampled interval with horizons of ascending thermal water. The Jurassic-Lower Cretaceous sequence occurs as a northwestern-dipping monocline, broken by faults and probably belongs to the complex filling the Zhokhov marginal trough of the Verkhoyansk -Chukotka orogen on the Eastern Arctic shelf.

Pathogenesis of the Hallux Valgus: Enthesopathy of the Metatarsosesamoid Ligament

Category: Bunion; Basic Sciences/Biologics Introduction/Purpose: It is generally accepted that failure of the medial supporting soft tissue structure of the metatarsophalangeal joint plays an important role in the development of hallux valgus. The metatarsosesamoid ligament (MSL), a component of the medial soft tissue, is an important structure that connects the metatarsal head and the sesamoid complex. The sesamoid complex works as a dynamic stabilizer of the metatarsal head. We hypothesized that the failure of the medial MSL causes instability of the first metatarsal bone, which leads to hallux valgus deformities. Therefore, the present study aimed to describe the detailed structure and degenerative findings of MSL and to clarify the mechanical stress of the MSL enthesis, considering the mechanism of failure of the medial supporting soft tissue structure. Methods: The first metatarsal heads and sesamoid bones with soft tissue were collected from twelve cadavers. Serial 4-μm thick section4-μm intervals and stained with toluidine blue (Fig. 1a). We described the detailed histological structures and degenerative findings of MSL. In addition, morphometric comparisons were made between the medial and lateral MSL entheses at the metatarsal head to evaluate the mechanical stress they. First, we measured the thickness of the uncalcified fibrocartilage (UF thickness) following a protocol adopted previously (Fig. 1b). Second, the degree of irregularity of the interface between the zones of calcified fibrocartilage and bone (CFB) at each enthesis was assessed as the ratio between the lengths of the CFB and the enthesis (CFB/ E ratio) (Fig. 1c). The differences in these parameters were evaluated using the paired T test and Wilcoxon signed-rank test (P &lt; 0.05). Results: We identified that the MSL entheses were fibrocartilaginous entheses, which consisted of four tissue zones. The region in which the MSL wraps around the articular surface of the metatarsal head contains a metachromatic area accompanied by fibrocartilage cells at the deep surface of the MSL, called the sesamoid fibrocartilage. At the MSL enthesis, pathological findings indicating enthesopathy were observed. One specimen showed the tear of the MSL at the wrap around region. The MSL enthesis tear was observed in two specimens with hallux valgus. Both UF thickness (P = 0.12, effect size r = 0.89) and CFB/E ratio (P = 0.17, effect size d = 0.35) were significantly greater in the medial MSL enthesis than those in the lateral MSL enthesis. Conclusion: In the present study, the MSL showed enthesis protecting structures such as enthesis fibrocartilage which contributes to dissipating bending forces during insertional angle change, complexed CFB interface which guards an enthesis against shearing forces and wrap around region which contributes to dissipating the shearing force to the enthesis. However, the medial MSL subject to the greater forces and the degenerative findings of enthesopathy were observed. On top of that, all four hallux valgus specimens with sesamoid complex dislocation showed MSL enthesis tear. Enthesopathy, particularly at the medial MSL, may be the cause of hallux valgus.

Paleoenvironmental reconstruction of Late Cretaceous rivers, Dinosaur Park Formation, Alberta, Canada

Dinosaur Provincial Park is a UNESCO World Heritage Site with one of the richest vertebrate fossil accumulations globally. The “badlands”-style topography exposes Upper Cretaceous (Campanian) meander-belt deposits of the Dinosaur Park Formation, providing an excellent opportunity for sedimentological and three-dimensional stratigraphic analysis. One of the main unknowns regarding the depositional environments of the Dinosaur Park Formation, specifically the proximity to the fluvial-to-marine transition zone, has been the subject of extensive debate. Our study aims to refine paleoenvironmental reconstructions of Late Cretaceous rivers through facies and facies associations analysis, meander-belt architecture characterization, and paleohydraulic parameter calculations.We investigate a ~7 m thick single-story meander-belt interval of the Dinosaur Park Formation. Six facies, four facies associations, and two architectural elements (both point bars) were identified from 20 stratigraphic sections. In addition, paleohydraulic reconstruction of the formative river channel was completed by estimating bankfull channel depth and width, paleoslope, and backwater length.Contrasting with previous interpretations of deposition (partially or wholly) influenced by tides, these data allow us to demonstrate that the meander-belt deposits of the Dinosaur Park Formation were deposited in a fluvial environment upstream of the fluvial–marine transition zone. Inclined heterolithic strata (IHS) present in the area are of fluvial origin, adding to the growing body of evidence for heterolithic bedding in fluvial point-bar environments. The newly inferred depositional setting for the studied portion of the Dinosaur Park Formation changes our understanding of the paleogeography of the Western Interior Seaway in western Canada and will allow paleontologists to revise the reconstructions of dinosaur habitats and better constrain the taphonomy of these globally significant fossil accumulations. Additionally, this study contributes to the validation and development of a systematic approach to the paleoenvironmental reconstruction of ancient river systems based on paleohydraulic analysis.