Pregnancy is associated with physiological changes, resulting in altered pharmacokinetics, which may impact antiretroviral drug exposure. To assure health and prevent vertical transmission of HIV, it is imperative to reach adequate drug exposure. This study aims to determine the impact of pregnancy on bictegravir pharmacokinetics, examine mechanisms responsible for lower exposure, report on placental transfer, safety, and efficacy. This open-label pharmacokinetic study, included women living with HIV who used bictegravir, emtricitabine with tenofovir alafenamide. Plasma samples were obtained in third trimester, as well as 4-6 weeks postpartum. If feasible, cord blood and maternal plasma at delivery were obtained. Sixteen participants were included. Geometric mean area under the curve for total bictegravir was 48.8 mg*h/L (coefficient of variation (CV) 25.9%) in third trimester and 99.2 mg*L/h (CV 32.9%) postpartum, with a geometric mean ratio (90% CI) of 0.49 (0.44-0.55); 24 h post-dosing, median (IQR) unbound fractions were 0.15 (0.13-0.18)% and 0.11 (0.10-0.13) during pregnancy and postpartum, respectively. Median (IQR) ratio between pregnancy and postpartum was 173.7% (127.8-305.7) for glucuronidation-metabolite (M15) and 200.7% (150.0-224.9) for sulfation-metabolite (M20). Low-level viraemia was noted in several participants, but no vertical transmission occurred. Cord blood maternal plasma ratio (IQR) was 1.3 (1.0-1.4). No congenital anomalies were reported. Although bictegravir exposure is decreased during pregnancy, mainly due to altered protein binding and increased glucuronidation and sulfation, trough levels remained above the PA-IC95. No vertical transmission occurred and no congenital anomalities were observed. Bictegravir was shown to have profound placental transfer.

Keratoconus (KC) is a progressive corneal disorder caused by impaired biomechanical integrity, leading to geometric deformation. Although corneal changes are well characterized, iris structural alterations across KC stages remain poorly studied. Accordingly, this study aims to compare quantitative iris characteristics among healthy controls and patients with different stages of KC. This retrospective cross-sectional study included 547 eyes: 497 from 264 keratoconus subjects classified according to the Topographic Keratoconus Classification (TKC) system as subclinical (n = 102), early stage (n = 219, TKC 1-2), and late-stage (n = 176, TKC 3-4), and single eyes from 50 healthy emmetropic controls. Anterior segment imaging was performed using Pentacam Scheimpflug tomography. Iris segmentation was achieved using a semi-automated Python-based pipeline incorporating the Segment Anything Model, followed by extraction of the anterior iris boundary. The iris was subdivided into basal, mid-iris, and pupil-edge regions. Region-specific geometric parameters, including curvature, arc length, and area under the curve (AUC), were computed using spline-based fitting and numerical integration. Group comparisons were conducted using one-way analysis of variance with false discovery rate correction, followed by age-adjusted analysis of covariance. Mean basal and mid-iris curvature showed significant overall differences across TKC stages, with a progressive reduction from healthy controls to late-stage KC (p = 0.01 and p < 0.001, respectively). In contrast, pupil-edge curvature showed an opposite trend, with the highest values in late-stage KC (p = 0.02). Iris arc length did not differ significantly between groups, whereas AUC exhibited a region-specific difference limited to the pupil-edge iris (p = 0.02). These findings remained statistically significant after age adjustment. Increased pupil-edge curvature in KC represents a geometric alteration that may be clinically relevant in eyes undergoing intraocular surgery, particularly in relation to anterior chamber dynamics and potential susceptibility to postoperative pupillary block. Conversely, mid-iris straightening may reflect structural variation within the iris in late-stage disease. Together, these findings suggest that corneal geometric changes in KC may be associated with subtle alterations in anterior chamber mechanical environment, potentially contributing to secondary changes in iris configuration.

Electrocatalysis offers a potential sustainable route toward plastic monomers, as exemplified by the electrooxidation of biomass derived 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). However, the scale-up of this process is largely limited by the availability of suitable anodic electrocatalysts. Here we developed a facile approach to fabricate self-supported Ni(OH)2 nanoarray through the corrosion of nickel foam under moist O2 atmosphere, resulting in an efficient and stable anode for HMF electrooxidation toward FDCA with 99% of Faradaic efficiency for 79 cycles. This method enables the scalable manufacture of a large-area, uniform nickel anode up to 8050cm2. The obtained electrodes enable continuous HMF electrooxidation coupled with hydrogen production in a membrane-free electrolyzer with a geometric electrode area of 80cm2 at 10A for 174h with high single-pass conversion (∼98%) and FDCA selectivity (∼93%). Finally, this system was showcased for solar powered FDCA electrosynthesis and its application in manufacturing polyethylene furandicarboxylate plastic for 3D printing. This work provides a promising strategy for scalable electrocatalytic biomass valorization.

Entanglement entropy in loop quantum gravity and geometrical area law

Abstract In earlier papers (McKee et al. in J Biomech Eng 143(8):081006, 2021; Rebolledo et al. in J Biomech Eng 145(1):014501, 2023), a mathematical representation of the Wheatley heart valve was developed dependent on two related parameters. In this article, we introduce a mathematical representation based on two related, but arguably more natural parameters, namely, the radius of a large circle and the radius of a smaller circle lying within the larger circle. In the previous design it was found (Oliveira et al. in Int J Numer Meth Biomed Eng 40(2):e3792, 2024) that under severe back pressure central bending of the leaflets was observed. In order to counter this, the idea of a structural support in the form of stays embedded within the leaflets is introduced. Each leaflet consists of two concatenated surfaces. In this paper, all the stays associated with the “first” surface will be shown to lie on that surface, i.e., can be embedded within the surface. Furthermore, they can be shown to meet at a common point when they are extended. This is also true of all stays for the “second” surface, although the common point will be different in this case. The proposed analytical expressions are used to perform computational simulations of reinforced Wheatley valves. The results show that both the number and position of the stays contribute to reducing local buckling, but may decrease the geometric orifice area. This observation shows that the proposed geometric parametrisation is appropriate for correctly designing of S-shaped leaflet reinforcements.

Accurate determination of the lithium‐ion diffusion coefficient ( ) is essential for understanding mass‐transport limitations in graphite anodes and for improving the performance of lithium‐ion batteries. However, the calculation of obtained from pulsed electrochemical techniques critically depends on the assumed active surface area, for which no standardized definition currently exists. In this work, we quantitatively assess how different surface area approximations—geometrical area, scanning electron microscopy‐derived area, and Brunauer–Emmett–Teller surface area—affect the diffusion coefficient extracted from galvanostatic intermittent titration technique and intermittent current interruption analyses. Both methods were applied to a commercial graphite electrode using an identical dataset, enabling a direct and unbiased comparison of diffusion trends. We show that the choice of surface area leads to variations in spanning several orders of magnitude, due to the squared dependence of the area term in the diffusion equation. Overall, our results demonstrate that careful and consistent surface area selection is crucial for reliable diffusion measurements and for ensuring comparability across studies.

Various designs are proposed for pulmonary expanded polytetrafluoroethylene (ePTFE) conduits and have been applied in clinical practice. However, experimental data to support them are limited. We conducted an in vitro experiment using a circulatory simulator to evaluate their haemodynamic performance and hydrodynamic characteristics. Three root models with a 24-mm basal ring (A, straight; B, with small sinuses; C, with large sinuses) were 3D-printed. Cusps were uniformly cut out from a 0.1-mm-thick ePTFE membrane and sewn to the inter wall of the models. Model A had a single suture on the free margins near the commissures. Each model was tested with a pump size of 70 mL, 70 beats/min, and arterial pressure of 30/10 mmHg. The valve behaviour was recorded by a high-speed camera, and particle image velocimetry (PIV) was performed in the region behind the model housing section. Peak transvalvular pressure gradients were 4.0, 4.8, and 4.3 mmHg (P = .95), and geometric orifice areas were 2.34, 2.38, and 2.46 cm2 (P = .96) in models A, B, and C, respectively. Particle image velocimetry revealed peak instantaneous velocity was 1.69, 1.69, and 1.65 m/s (P = .74) and peak Reynolds shear stress in the midsystolic phase was 56.8, 49.5, and 25.5 Pa (P = .05) in models A, B, and C, respectively. Model C tended to have a lower distribution of turbulent flow than the other models. All models exhibited sufficient opening and acceptable Reynolds shear stress values. The sinus contributed to the suppression of turbulent flow, which may lead to an improvement of conduit durability, but its effect was dependent on the sinus size.

Transcatheter mitral valve replacement (TMVR) is a preferred interventional option for high-risk patients with severe mitral regurgitation who are ineligible for transcatheter edge-to-edge repair. However, the role of annular dimensions in risk stratification has been marginally explored in this distinct anatomical setting with preserved native leaflets in patients with varying degree of myocardial damage. This subanalysis of the multicenter TENDER registry (NCT04898335) included 145 TMVR patients. Preprocedural 4D-computed tomography-derived annular dimensions were evaluated for associations with cardiac and all-cause mortality. At 1 year, all-cause mortality was 24.8% (n = 36 of 145) and cardiac mortality was 5.5% (n = 8 of 145). Cardiac deaths were associated with significantly larger annular parameters, including systolic and diastolic anteroposterior diameter (32.8 ± 2.3 mm vs 29.9 ± 3.5 mm, P = .023; 33.2 ± 2.5 mm vs 30.3 ± 3.4 mm, P = .018), systolic and diastolic annular perimeter (126.1 ± 9.5 mm vs 115.8 ± 10.5 mm, P = .008; 125.6 ± 10.4 mm vs 115.8 ± 12.7 mm, P = .034), and annular area (1271.7 ± 193.2 mm2 vs 1076.2 ± 193.6 mm2, P = .006; 1262.7 ± 209.9 mm2 vs 1087.2 ± 194.7 mm2, P = .015). Annular area loss, calculated as the difference between native diastolic mitral annular area and the geometric effective orifice area of the implanted valve, was significantly greater in patients who died for cardiac reasons (999.72 ± 225.72 mm2) compared with survivors (826.68 ± 189.45 mm2; P = .022; odds ratio, 1.005, P = .030). Larger annular dimensions and greater annular area loss may predict 1-year cardiac death. Possible mechanisms include impaired left ventricle filling, artificial inflow-related outflow tract obstruction, and limited reverse remodeling. Comprehensive annular assessment may also enhance patient selection for future transseptal TMVR systems.

This paper investigates the physical significance of ear-canal wave quantities-such as absorbance-that are commonly measured in wideband-acoustic-immittance tests and evaluates whether these quantities uniquely characterize middle-ear function. This is explored using simulations of lumped-element and transmission-line ear canals, along with measurements in three-dimensional-printed uniform and anatomical ear canals of varying geometry, terminated by the same middle-ear simulator. The results demonstrate the following points: (1) Wave quantities computed using estimated or geometrical cross-sectional areas do not uniquely characterize the middle ear because they describe the wave interaction between ear canal and middle ear and are therefore confounded by variations in ear-canal geometry. (2) At low frequencies, the reflection of sound waves in the ear canal plays a negligible role in the middle-ear transduction mechanism because of the long sound wavelength relative to ear-canal length, and wave quantities therefore do not provide a meaningful physical characterization of middle-ear function. (3) Wave quantities computed using an invariant cross-sectional area are likely most appropriate for clinical diagnostics, as they reduce the influence of ear-canal geometry up to approximately 3 kHz. However, this simplification means that wave quantities no longer characterize the reflection of sound waves in the ear canal at any frequency.

It is generally acknowledged that computer-aided drafting (CAD) has rendered traditional construction and descriptive geometry methods obsolete. This two-part study experimented with SolidWorks in these two geometric areas by investigating assignments submitted by first-year engineering students at the Botswana International University of Science and Technology. The first part, conducted in 2017, used a simple geometric shape to train a cohort of 178 students on how SolidWorks could be used to mimic traditional construction geometry methods to model the shape. Participants were then assigned more complex geometries to apply appropriate SolidWorks methods to mimic the construction geometry methods of the assigned shapes. The students worked in groups of at least five members and completed the assignments in a three-hour lab session. The second part, conducted in 2024, addressed the visualization dilemma associated with the passive, teacher-centered methods used in demonstrating the descriptive geometry rabatment process. Another cohort of 557 students, working in groups of at least six members, developed SolidWorks models to demonstrate the process. This cohort was given over 12-hour lab sessions to complete the task. The results from the construction geometry experiments show that participants struggled to mimic traditional drawing techniques in SolidWorks, while the descriptive geometry cohort developed meaningful SolidWorks rabatment process models. These two CAD-based approaches are pedagogically important because, in the first part, traditional construction geometry was extended into platforms that support e-learning, while in the second part, a flipped learning approach to descriptive geometry was introduced.

ABSTRACT Coal and graphite are both carbon-based materials with comparable aromatic carbon frameworks, therefore, flat graphite slit pores are widely used as simplified adsorbent models in adsorption studies. However, coal surfaces are often intrinsically curved at the nanoscale. In this work, we constructed a curved graphite slit-pore model and carried out grand canonical Monte Carlo (GCMC) simulations to investigate the adsorption of three representative coalbed methane (CBM)-related gases (CH₄, CO₂, and N₂), with the results systematically compared against those from a conventional flat graphite slit-pore model and available experimental adsorption data. The results show that curved graphite pores can serve as a useful surrogate for curved carbonaceous surfaces in coal, but curvature does not automatically lead to higher adsorption solely due to a larger geometric surface area. Instead, the relative adsorption performance of curved versus flat pores depends on both the adsorbate species and pressure regime. Microscopic analyses further reveal that the adsorbed molecules form clustered/aggregated distributions in both pore types, and the characteristic cluster size increases with the molecular size of the adsorbate. These findings highlight the importance of incorporating surface curvature when using graphite-based slit pores to rationalise gas adsorption in coal-like carbon frameworks.

A simple mechanical polishing treatment of commercial solid-gold electrodes (SGEs) can renew the active gold surface, reduce manufacturing-related grooves, and markedly improve the repeatability of geometric-area estimation and the analytical performance in stripping voltammetry. The work focuses on the accurate determination of the geometric area of a SGE by two voltammetric techniques. Cyclic voltammetry (CV) at different scan rates, referred to as the Randles–Ševčik equation, and voltage scans at different electrode rotation rates, based on the Levich equation, were performed. The geometric area of the SGE was also evaluated by scanning electron microscopy (SEM). Commercial SGEs show grooves on their surface, derived from the fabrication processes. The effects of these grooves on the voltammetric response were investigated. The measurements were carried out on the SGE both as received from the manufacturer and after a reduction in the grooves height by a drastic mechanical treatment. After the treatment, the estimated area values were lower and more precise (3.05 ± 0.02 mm2). Moreover, the reduction in the grooves’ height affected the area estimations in contrast with the meaning of the geometric area, as intended by the Randles–Ševčik and Levich equations. Furthermore, the gold exposed surface was measured by CV in sulphuric acid. Finally, the SGE was tested for the detection of Hg in a NaCl solution by anodic stripping voltammetry: the repeatability of the response improved after the mechanical treatment, confirming the usefulness of this step before electrode usage.

A modified attachment energy model combined with classical molecular dynamics simulations is employed to study the solvent-dependent crystal growth of α-CL-20 in six solvent systems commonly used for the preparation of CL-20: maleic acid, pentaerythritol, glycine, citric acid, polyvinyl alcohol, and butyl carbamate. Surface roughness is quantified via the ratio of solvent-accessible area to geometric cross-sectional area, and electrostatic potential maps and radial distribution functions are used to characterize the polarity and non-bonded interactions at the interfaces. The results show that the interactions between α-CL-20 and solvent are dominated by hydrogen bonding, with some contributions from van der Waals contacts. The calculation results based on modified attachment energy theory show that in all six solvent systems, the growth of the (021) face is substantially inhibited, while the (020), (102), (111), and (002) faces tend to remain as persistent, moderately growing facets. The predicted morphologies in solutions evolve from the prismatic vacuum habit toward nearly polyhedral, spheroidal crystals, which suggest that strong, face-selective hydrogen bonding on rough, polar faces can serve as an effective microscopic mechanism for solvent-based morphology engineering of CL-20. METHODS: The Materials Studio software was used to calculate crystal growth, electrostatic potential, and radial distribution functions of α-CL-20. The VISTA software was used to predict morphologies of α-CL-20 in six solutions.

Contrastive learning unlocks geometric insights for dataset pruning.

Consumption of vegetables is associated with numerous health benefits as they enrich the diet with vital minerals and vitamins, besides providing other nutritionally important components including fibre. Prevalence of the fast foods and eating-outs have somehow affected the pattern of vegetable consumption. Realizing the importance of vegetables in the diet and for pushing forward the case of its increased consumption the United Nation General Assembly has declared 2021 as the &ldquo;International Year of Fruits and Vegetables&rdquo;. Among the seasonal vegetables cucurbitaceous crops viz bitter gourd spine gourd, and sweet potato have high medicinal and nutritional value. The summary of measured and calculated geometrical characteristics of bitter gourd, spine gourd and sweet potato in Table1. The average values of major, median and minor diameters of bitter gourd, spine gourd and sweet potato were 16.54, 3.35, 2.83cm, 3.34, 2.18, 1.87 cm, 8.42, 3.02 and 2.77 cm respectively (Table1). The average Geometric mean, Sphericity and Surface area of bitter gourd, spine gourd and sweet potato were 5.383 mm, 165.58, 90.87 cm2 2.410 mm, 270.43, 14.34 cm2 4.121 mm, 212.09 and 53.31 cm2 respectively (Table1). The shape of bitter gourd spine gourd and sweet potato compared with the standard chart (Mohsenin, 1986) [20] and can be consider as spindle-shaped, oval and circular. The average weight, length, diameter and volume were determined. The required fruits were taken randomly for examination of physical parameters (Kusat et al., 2021) [18]. Biochemical properties of bitter gourd, spine gourd and sweet potato were determined. The biochemical properties are proximate and chemical analysis of bitter gourd, spine gourd and sweet potato. In a study of bitter gourd the average nutritional value per 100g edible vegetable was found to contain 90.2 per cent moisture, 4.2g carbohydrate, 1.46g protein, 0.26g fat, 2.34g fibre and 1.36g total sugars (Table 2). In spine gourd the average nutritional value per 100g edible vegetable was found to contain 86.5 per cent moisture, 4.4g carbohydrate, 2.1g protein, 0.3g fat, 2.8g fiber and 0.89g total sugars (Table 2). In sweet potato the average nutritional value per 100g edible vegetable was found to contain 67.2 per cent moisture, 20.4g carbohydrate, 1.47g protein, 0.11g fat, 1.67g fiber and 1.12g total sugars (Table 2). &nbsp;

Limited comparative evidence exists on how polyamine-based edible coatings, in combination with various packaging systems, simultaneously influence the physical stability and biochemical quality of "Red Delicious" apples during storage. In this study, the effects of edible coatings (spermidine, putrescine, and chitosan) and packaging methods (unpacked, plastic film, and zipper bags) on physical properties (length, thickness, geometric mean diameter, weight, and surface area) and chemical attributes (pH, total soluble solids, total phenolics, flavonoids, and antioxidant activity) were evaluated. ANOVA results indicated that both coatings and packaging significantly influenced apple quality during storage, whereas their interaction effects were generally negligible. Packaging played a more critical role in maintaining dimensional stability, while coatings-particularly spermidine-were more effective at reducing weight loss and geometric alterations. Conversely, coatings significantly preserved phenolic compounds and antioxidant activity, whereas packaging exerted a stronger influence on pH and total soluble solids. Among the packaging treatments, zipper bags demonstrated the best performance in minimizing moisture loss and preserving dimensional integrity. Spermidine coating, on the other hand, showed the greatest efficacy in maintaining both chemical and physical quality attributes. Overall, the combination of spermidine coating and zipper bag packaging is recommended as an efficient and cost-effective postharvest strategy. This approach not only reduces postharvest losses and extends shelf life but also preserves the nutritional and market value of apples, offering substantial economic and export benefits for the horticultural industry. These findings provide actionable guidance for postharvest management and highlight the potential of integrated coating-packaging interventions to reduce losses and enhance value in fruit supply chains.

The Brunauer-Emmett-Teller (BET) technique, despite its widespread use, often yields overestimated specific surface area (SSA) values because it neglects surface curvature. The recently developed Alinaghipour-Falamaki (AF) theory [Alinaghipour and Falamaki, PCCP 2023, 25, 8424-8438] introduces curvature correction and achieves realistic SSA predictions for monosized dense particles and mesoporous materials with narrow pore size distributions. However, its applicability to materials with distributed or complex pore structures remained limited. In this work, we extend the AF theory by integrating it with a modified Barrett-Joyner-Halenda model and propose a new approach for directly determining the surface energy parameter from the desorption isotherm. The resulting algorithm, implemented in an open-source code named HAF-BET, enables accurate SSA and surface energy parameter calculations for mesoporous materials with arbitrary pore size distributions and geometries. When applied to reference materials with known geometrical surface areas, the HAF-BET algorithm achieved average errors of 13% for cylindrical and 22% for spherical pores, significantly outperforming the conventional BET and Shimizu-Matubayasi methods (errors exceeding 45%) [Shimizu and Matubayasi, Langmuir 2022, 38, 7989-8002]. Across 51 additional mesoporous samples, HAF-BET consistently produced SSA and surface energy values that were 34 and 56% lower, respectively, than those predicted by the BET method, confirming its reliability. Developed primarily for cylindrical mesopores, the algorithm also proves effective for other curved mesoporous materials, producing SSA values approximately 28% lower than those obtained by the BET method and thus serving as a reliable, curvature-aware alternative for surface area estimation of all mesoporous materials with curved surfaces.

This work explores late-time gravitational collapse using timelike thin-shell methods in classical general relativity. A junction surface separates a regular de Sitter interior from a Schwarzschild or Schwarzschild-de Sitter exterior in a post-transient regime with fixed exterior mass M (ADM for Λ+=0), modelling a vacuum-energy core surrounded by an asymptotically classical spacetime. The configuration admits a natural thermodynamic interpretation based on a geometric area functional Sshell∝R2 and Tolman redshift, both derived from classical junction conditions and used as an entropy-like coarse-grained quantity rather than a fundamental statistical entropy. Key results include (i) identification of a deceleration mechanism at the balance radius Rthr=(3M/Λ-)1/3 for linear surface equations of state p=wσ; (ii) classification of the allowable radial domain V(R)≤0 for outward evolution; (iii) bounded curvature invariants throughout the shell-supported spacetime region; and (iv) a mass-scaled frequency bound fcRS≤ξ/(33π) for persistent near-shell spectral modes. All predictions follow from standard Israel junction techniques and provide concrete observational tests. The framework offers an analytically tractable example of regular thin-shell collapse dynamics within classical general relativity, with implications for alternative compact object scenarios.

Transcatheter aortic valve-in-valve is frequently performed in degenerated surgical valves. Notably, in small-sized surgical valves, bioprosthetic valve fracturing can improve the functional results of the transcatheter heart valve (THV). Therefore, this study aimed to investigate the impact of an expandable surgical valve on the functional improvement of 2 THV models. An Inspiris Resilia (21 mm) and 2 different THV models-the self-expanding Evolut-PRO and the balloon-expandable SAPIEN 3 (each 23 and 26 mm)-were used for hydrodynamic testing at 4 different circulatory conditions in a pulse duplicator. Mean pressure gradient (MPG), effective orifice area (EOA), geometric orifice area (GOA), minimal internal diameter (MID), and pin-wheeling index (PWI) of the THVs were analysed before and after expansion of the Inspiris Resilia with a non-compliant balloon (6 atm). Leaflet kinematics were evaluated by high-speed video recording. The internal and external diameters of Inspiris Resilia were measured with a calliper gauge. Fluoroscopic images were recorded. The Inspiris Resilia showed 2 mm enlarged internal and external stent diameters after expansion, which are fluoroscopically visible. EOA and MPG of the THVs as valve-in-valve did not change significantly after the expansion of the Inspiris Resilia. However, the Inspiris Resilia expansion improved leaflet kinematics, resulting in an increased GOA and a decreased PWI of the THVs as valve-in-valve. The expansion of the Inspiris Resilia enlarged the stent diameter, resulting in improved leaflet kinematics of the THVs as valve-in-valve. These findings may be helpful for valve-in-valve interventions, especially in small-sized surgical valves.

Navigating the complexities of electrocatalytic water splitting: a critical examination of pitfalls and considerations in performance evaluation