Area Ratio Research Articles

Generalized Beer-Lambert Law for Evaluating the Absorption of Heterogeneous Sunscreen Films.

In this study, we first examined the morphology of a sunscreen product deposited on PMMA plates with an increasing developed interfacial area ratio (Sdr) to better understand the origin and impact of film heterogeneities on in vitro sun protection factor (SPF) measurements. This was achieved using a simple yet innovative UV photography setup combined with wetting measurements. By revisiting the fundamentals of absorption spectroscopy, we generalized and extended Beer-Lambert's law to nonuniform samples, modeling thickness distributions with a Gamma law. This enabled us to develop an analytical relationship between absorbance, thickness, and homogeneity of spread sunscreen films using the concept of linear attenuation coefficients. This model, which differentiates between spreading quality and absorption potential, was experimentally validated on three different sunscreens coated on smooth PMMA plates. It also helps explain the low correlation often observed between in vivo and in vitro tests, especially for high SPF values. We believe this approach will pave the way for more reproducible and consistent in vitro SPF measurements, leading to the development of more effective sunscreen products.

Numerical investigation of heat transfer enhancement in a double pipe heat exchanger using tangential perforated ring turbulators

This research investigates the heat transfer and fluid flow characteristics of a double pipe heat exchanger enhanced with perforated turbulators. The study focuses on the effects of varying Reynolds numbers and geometric configurations, par-ticularly the number of perforations in the inserts, on thermal performance. Using the finite volume method and Ansys Fluent simulations, the heat exchanger was analysed under different conditions, comparing the results with a smooth tube configuration. The findings reveal that the pitch ratio of 2.5 has shown the highest heat transfer capacity followed by pitch ratios of 4.5 and 6.5. Further, irrespective of relative pitch ratio, the ring with no perforations has shown the highest value of average Nusselt number and in the case of perforation, the open area ratio of 0.068 has yielded the best thermal perfor-mance.

Implementing Sustainable Cryo-MQL Grinding Practices for Improvement of Tribological Characterizes of Inconel 625

Abstract Cryo-MQL is an impactful, sustainable cooling/lubrication approach that addresses constraints such as wheel loading and thermal damage of ground Inconel 625 caused by its low thermal conductivity and work hardening tendency. The present investigation explores the eco-friendly Cryo-MQL approach, i.e., LN2 with groundnut oil-based sustainable grinding, to enhance the grindability and surface integrity of Inconel 625. For confirmation, cryo-MQL outcomes, including grinding forces, roughness parameters, bearing area analysis, grinding temperature, surface morphology, and microhardness, have been compared with dry and MQL outcomes. The results indicate that cryo-MQL exhibits excellent surface tribological performance in lower skewness and kurtosis parameters with a higher bearing area ratio, i.e., 78.84%, and free-from grinding burn and redeposition layer formation. Besides, lower grinding forces and temperature with no significant microhardness change highlighted a better grindability of high-strength alloy. Finally, chip morphology investigations under various conditions have been performed to gain further insights into the grindability of Inconel 625 in terms of negligible wear tracks with long C-type microchips. Therefore, it can be concluded that cryo-MQL grinding safeguards the surface qualities of the ground surfaces and provides clean grinding conditions.

Age-specific gender differences in morphological parameters of intracranial aneurysms.

Gender differences are shown to exist in the incidence and outcome of subarachnoid hemorrhage as well as in the formation and progression of intracranial aneurysms. However, few studies investigated the gender difference in the morphology of intracranial aneurysms. A total of 308 consecutive patients with 346 intracranial aneurysms from 2014 to 2020 were retrospectively analyzed. Differences in 10 morphological parameters of intracranial aneurysms between males and females were compared. Continuous variables were expressed as the median [interquartile range (IQR)] and the differences were analyzed using the Mann-Whitney test. Categorical variables were expressed as numbers (frequencies) and the differences were analyzed using χ2 test. Moreover, subgroup analyses were performed according to age stratifications: ≥60 years, 50-59 years, and <50 years. The median aspect ratio maximum [1.38, IQR (1.17-1.83) vs. 1.27, IQR (1.00-1.57)], median aspect ratio [1.29, IQR (1.00-1.76) vs. 1.18, IQR (0.93-1.54)], median bottleneck factor [1.17, IQR (1.00-1.47) vs. 1.03, IQR (0.86-1.27)], and median volume-to-ostium area ratio [5.67, IQR (2.85-9.03) vs. 3.86, IQR (1.94-7.48)] in males were significantly higher than those in females (all P < 0.01). Particularly, the differences in the above morphological parameters between genders were most prominent in patients aged ≥ 60 years, whereas no differences were found in patients aged < 50 years. There were no significant differences in other morphological parameters between males and females, including neck width, transverse, height, maximum, aneurysm volume, and height-width ratio. Gender difference existed in the morphology of intracranial aneurysms and was affected by age. The difference was prominent in patients aged ≥ 60 years, whereas no difference was found in patients aged < 50 years.

Looking at or beyond the tumor - a systematic review and meta-analysis of quantitative imaging biomarkers predicting pancreatic cancer prognosis.

To evaluate the prognostic value of quantitative imaging biomarkers derived from computed tomography (CT) and magnetic resonance imaging (MRI) for pancreatic cancer (PC), with a particular focus on body composition parameters beyond the traditional intrinsic features of the tumor. PubMed, EMBASE, and Cochrane Library databases were searched for articles on quantitative imaging biomarkers obtained from CT or MRI in predicting PC prognosis published between January 2014 and August 2024. The Newcastle-Ottawa scale was used to assess the quality of the included studies. Survival outcomes, such as overall survival (OS) and recurrence-free survival (RFS), were evaluated. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. In case of high heterogeneity, subgroup analyses and sensitivity analyses were performed to identify potential sources of heterogeneity among the studies. We performed a meta-analysis of ten imaging biomarkers investigated in 43 included studies. Larger tumor size, lower skeletal muscle radiodensity, lower skeletal muscle index (SMI), presence of sarcopenic obesity, lower psoas muscle index (PMI), higher visceral to subcutaneous adipose tissue area ratio, and lower visceral adipose tissue index were associated with significantly worse OS. In particular, lower SMI and lower PMI had relatively high HRs (1.65 for SMI, 95% CI 1.39-1.96, and 2.20 for PMI, 95% CI 1.74-2.78). Patients with lower SMI exhibited poorer RFS (HR 1.78, 95% CI 1.46-2.18). Subgroup analyses identified the origin region of the study and intervention type as potential factors of heterogeneity for SMI in predicting OS. Imaging biomarkers indicating body composition at PC diagnosis may play an important role in predicting patient prognosis. Further prospective multi-center studies with large sample sizes are needed for validation and translation into clinical practice.

Spatio-temporal Characteristics and Obstacle Factors of the Coupling Synergy Between New-type Urbanization and Low-carbonization of the Living Energy Consumption of Urban Residents

Clarifying the dynamics and mechanism of the coupling and coordination relationship between new-type urbanization and the low-carbonization of the living energy consumption of urban residents can provide basic data and theoretical support for the national low-carbon economy and other high-quality development strategies from the perspective of urbanization. The entropy method, coupling coordination model, kernel density estimation, and obstacle model were used to investigate the spatial and temporal characteristics, coupling coordination, and obstacle factors of the two systems of China's new-type urbanization and the low-carbonization of the living energy consumption of urban residents from 2005 to 2021. The results showed that： ① The overall level of new-type urbanization and low-carbonization of the living energy consumption of urban residents showed an upward trend, and both had obvious spatial differentiation characteristics. ② The coupling coordination degree of new-type urbanization and the low-carbonization of the living energy consumption of urban residents showed a clear upward trend, increasing from 0.553 in 2005 to 0.714 in 2021. The overall spatial pattern of the coupling coordination degree exhibited a strong positive correlation, spatial correlation was enhanced, local spatial structure and dependence of the direction of the fluctuation were weak, and certain path dependent characteristics were observed. ③ Economic urbanization was the dimension with the biggest obstacle in the guideline layer of the new-type urbanization system, with an average obstacle degree of 34.77%； the built-up area ratio was the indicator with the biggest obstacle degree in the system, with an average obstacle degree of 23.48%. In the system of low-carbonization of the living energy consumption of urban residents, the indicator of carbon emission per unit of energy consumption had the strongest barrier effect, with an average barrier degree of 29.13%, whereas the indicator of carbon emission density had the weakest barrier effect, with an average barrier degree of 3.34%. Therefore, each province is recommended to construct development plans according to local conditions, establish a cross-regional and multi-dimensional synergy and cooperation mechanism, and promote the construction of new-type urbanization in an orderly manner, to facilitate the realization of the "dual-carbon" goal.

Investigation of cracking behavior in asphalt pavement using digital image processing technology

IntroductionRoad hazards and some traffic accidents are often caused by damage of the performance of the pavement due to cracking of asphalt concrete.MethodsA simulation test was designed to investigate asphalt pavement cracking under different temperature conditions (15°C, 0°C, −5°C, −15°C) with a fixed traffic load strip. Using Gaussian filtering to eliminate texture noise (5 × 5 convolution kernels), extracting continuous crack contours through Canny operator (dual threshold 0.7/0.3), and combining with improved Otsu algorithm (32 × 32 block dynamic threshold) to achieve accurate segmentation under complex lighting conditions; Innovatively introducing a dual parameter system of fractal dimension (box dimension method) and crack rate (crack area ratio) to quantitatively characterize the complexity of crack morphology and degree of damage.ResultsAnd proposed using two crack characteristic parameters, fractal dimension and crack rate, to describe the extension characteristics of cracks. The results indicate that the road surface is more prone to cracking in negative zero temperature environments, with the number and rate of cracks generated at −15°C being much higher than the other three low-temperature environments. Compared to the 15°C environment, the crack rate increased by 18.26%.DiscussionIt has been confirmed that the occurrence and propagation of cracks will be exacerbated in low-temperature environments. The research results provide a theoretical basis and reference significance for the study of pavement crack resistance in cold regions.

Determinants of Cropping Intensity in Drought Prone Areas of Bogura

This study assessed cropping intensity and its influencing factors in the drought-prone areas of Bogura district, Bangladesh. Data were collected from 105 randomly selected farmers across four villages using a structured interview schedule. Cropping intensity, calculated as the ratio of gross cropped area to net sown area, ranged from 200% to 300%, with an average of 277.9%. The majority (84.7%) of farmers achieved more than 268% cropping intensity. Key factors positively influencing cropping intensity included the use of machinery for tilling, water management through underground water extraction, and the cultivation of short-duration crops. However, challenges such as surface water scarcity, poor drainage, inadequate infrastructure, low soil organic matter, and limited natural water bodies hindered intensification. Additionally, farmer’s education levels, annual income, and access to communication media significantly impacted cropping intensity. The study highlights the need for improved irrigation facilities, enhanced extension services, and better infrastructure to sustain high cropping intensity in drought-prone regions.

Fetal Body Composition in Twins and Singletons

ImportanceAn emerging paradigm attributes third-trimester fetal growth deceleration in uncomplicated twin pregnancies to an evolutionary adaptive process. Evaluating longitudinal fetal soft-tissue development may provide important insights into differential fetal growth trajectories between twins and singletons.ObjectiveTo compare twin vs singleton lean and fat tissue growth across pregnancy.Design, Setting, and ParticipantsProspective cohort study of dichorionic twins and singletons with serial ultrasound scans to chart fetal growth (2009-2013) and collect fetal volume data to measure fat and lean tissue (2015-2019) in 12 US clinical centers. Participants were individuals with singleton (n = 2802 enrolled) and twin (n = 171 pairs enrolled) pregnancies who generally had no chronic disease. Data analysis was performed from September 2023 to June 2024.ExposureTwin status.Main Outcomes and MeasuresAbdominal area, maximum abdominal subcutaneous tissue thickness, fractional thigh volume, fractional lean thigh volume, fractional fat thigh volume, midthigh area (including lean and fat components), ratio of fractional fat thigh volume to fractional thigh volume, and ratio of midthigh fat area to midthigh area, measured up to 6 times between 15 and 37 weeks’ gestation.ResultsAnalyses included 315 twin and 2604 singleton fetuses. The mean (SD) maternal age at delivery was 31.3 (6.1) years for twins and 28.2 (5.5) years for singletons, with a mean (SD) gestational age at delivery of 35.2 (4.2) weeks for twins and 39.2 (1.7) weeks for singletons. Mean twin abdominal measurements were significantly smaller than those of singletons between 25 and 37 weeks’ gestation for area (difference at 25 weeks, −48.6 [95% CI, −102.2 to −5.1] mm2; difference at 37 weeks, −480.5 [95% CI, −677.2 to −283.5] mm2) and between 27 and 37 weeks for maximum abdominal subcutaneous tissue thickness (difference at 27 weeks, −0.13 [95% CI, −0.24 to −0.02] mm; difference at 37 weeks, −0.40 [95% CI, −0.68 to −0.13] mm). Beginning at 15 weeks, fractional thigh volumes were significantly smaller for twins (mean fractional thigh volume difference, −0.11 [95% CI, −0.16 to −0.07] cm3; mean fractional fat thigh volume difference, −0.08 [95% CI,−0.12 to −0.05] cm3) relative to singletons, persisting through 37 weeks (mean fractional thigh volume difference, −7.55 [95% CI, −11.76 to −3.34] cm3; mean fractional fat thigh volume difference, −5.60 [95% CI, −8.37 to −2.82] cm3). Mean fractional lean thigh volume was significantly smaller for twins at 15 to 16 and 23 to 36 weeks. For the ratio of fractional fat thigh volume to fractional thigh volume, twins had a 2.7% to 4.2% smaller fat percentage between 15 and 37 weeks compared with singletons.Conclusions and RelevanceTwins had proportionally less fat tissue accumulation in utero compared with singletons as early as 15 weeks’ gestation, when competition for nutritional resources was low. Persistent findings of smaller twin sizes and less fat accumulation across pregnancy support the concept of an early evolutionary adaptive process in otherwise uncomplicated dichorionic twin growth.

An innovative underdriven multi-degree-of-freedom sea turtle hydrofoil design

This study presents a new design for a multi-degree-of-freedom underdriven mechanism. The aim is to achieve efficient bionic motion of a sea turtle hydrofoil with multi-degrees-of-freedom using a single drive source. The design focuses on the kinematic characteristics of the hydrofoil. The design and modeling of the bionic hydrofoil are completed by accurately extracting and fitting the contours of the leading and trailing edges of the sea turtle hydrofoil. The article presents a detailed data analysis of the motion performance of the bionic hydrofoil through pool experiments combined with CCD camera shots. The experimental results reveal that the underdriven bionic hydrofoil moves at a frequency of 0.5 Hz. The correlation coefficients of the waving and rotation angles between the sea turtle hydrofoil and the bionic hydrofoil in the underwater experiments exceed 0.95. The total integral area ratio of the waving angle change curve and rotation angle change curve is more than 0.9. It is demonstrated that the new drive scheme proposed in this paper can realize a single actuator to control the motion of a sea turtle in three degrees of freedom. Breaking away from the traditional paradigm of independent multi-motor drives, the realization of 'input-output' motion mapping through mechanical design is of great significance for the complexity reduction of robot control systems.

Plasma Immersion Ion Implantation Increases Adhesive Bond Strength of PEK and PEEK to Dental Composites and Enables Hydrolysis Resistance

AbstractThe additive manufacturing technology known as selective‐laser‐sintering is available for the poly‐aryl‐ether‐ketone (PAEK) family of high‐strength polymers, enabling the rapid production of personalized dental and mandibular reconstructions at or near the point‐of‐care. PAEK mandibular segmental replacements, bridges, and abutments are transitioning to clinical use. There remains a need for improved adhesion between PAEK polymers and dental adhesives including dental composite resin cements. Without surface modification, there is a weak bond to PAEK polymers, especially when the surface of the polymer is smooth. Plasma‐immersion‐ion‐implantation (PIII) is applied to demonstrate a significant increase in the bond strength between Polyether–ether–ketone (PEEK) and Poly–ether–ketone (PEK) polymers and a commonly used dental composite resin cement, for multiple levels of interface roughness. A validated predictive model for the bond strength as a function of surface roughness expressed as a surface area ratio is presented that demonstrates the relative effect of PIII and mechanical interlocking. The results show that the bond strength achieved using PIII is retained even when the primer step is omitted, an important advance as the primer has been associated with hydrolysis‐induced weakening. A long‐term water immersion test shows that the PIII‐assisted primer‐free bond retains its strength while all primer‐assisted bonds are weakened.

Automated terrain roughness assessment using remotely sensed data

ABSTRACT In forestry, assessing and navigating terrain is crucial for operational efficiency. Terrain trafficability, the capacity to support vehicle passage, affects machinery movement and soil health. While soil’s weight-bearing ability is crucial, terrain classification is equally important for defining an area’s characteristics. This study automates terrain roughness estimation using UAV imagery to generate high-resolution roughness maps. We used deep learning for object segmentation, followed by point cloud classification and ground roughness quantification. Manual field measurements validated the segmentation results while manipulating the obstacle dataset tested the roughness algorithm’s sensitivity. Additionally, drone-derived Digital Surface Models (DSM) were used to calculate the Terrain Roughness Index (TRI), Vector Roughness Measure (VRM), and Area Ratio (AR) for comparison. Obstacle segmentation achieved 95.6% accuracy, while height estimation had an RMSE of 2.62 cm and an MRE of 11.4%. Manipulating the dataset demonstrated the method’s responsiveness to changes in obstacle density and height. The trend in TRI and AR values (ρ = 0.63, p < 0.05); (ρ = 0.67, p < 0.05) showed that the method classifies areas similarly to TRI and AR. Contrarily, VRM (ρ = 0.24, p = 0.13) did not align well with the roughness method used. This study highlights the potential to automate and improve roughness assessment, thereby improving operational efficiency and enabling better adjustments in performance expectations and cost estimation in forest operations.

Quantitative electroencephalography in children with attention deficit hyperactivity disorder and healthy children: Behavioral and age correlates

This pilot study aimed to identify quantitative electroencephalographic (qEEG) biomarkers for children and adolescents with attention deficit hyperactivity disorder (ADHD). We examined whether qEEG power correlates with the behavioral symptoms. We included 89 children with ADHD and 77 healthy children as a control group. We conducted EEG spectral analysis in the eyes-closed and eyes-opened conditions and compared the findings with a normative database (Human Brain Index). We measured behavioral parameters by using scales proposed by Barkley. The findings revealed an age-dependent decrease in qEEG power in children with ADHD. We found significant discrimination between children with ADHD and healthy children in the theta/beta ratio and theta activity in the frontal area. We found a notable increasing trend in beta activity across two age groups (6–10 years and > 10 years). Correlation analysis showed an association between qEEG power and hyperactivity in younger children with ADHD, while theta activity in the frontal region correlated positively with hyperactivity. The qEEG power of children with ADHD decreased gradually as age increased, and these changes were related to their symptoms. This pilot study suggests that qEEG differences between children with ADHD and healthy children may serve as a sensitive diagnostic tool, depending on the child’s age. Further research building upon these findings could deepen our understanding of ADHD and its neural correlates.

Contribution of GIS to the Characterization of Urban Green Spaces: Case of Cocody Municipality, Abidjan, Southeastern Côte d'Ivoire

In the municipality of Cocody (Abidjan), public green spaces are increasingly threatened by demographic pressure and urban expansion, reducing their availability and accessibility in favor of other priorities. To date, the lack of studies incorporating georeferenced data prevents the assessment of whether the remaining areas are sufficient to ensure residents' well-being. This raises a key question: How can Geographic Information Systems (GIS) contribute to the characterization of Cocody's green spaces? This study aims to answer this question by evaluating whether the available green space per capita aligns with urban planning and well-being standards. Specifically, the study describes the spatial distribution of green spaces in Cocody, assesses the ratio of green space area to population, determines their diversity, and identifies their uses. The methodology involved a field inventory, digitization of green space boundaries using recorded coordinates, and user surveys. The results indicate that Cocody has 42 public green spaces distributed across 16 of its 26 neighborhoods. The floristic diversity includes 169 plant species from 146 genera and 63 families. In terms of available green space per capita, the analysis reveals a very limited surface area, with a ratio of 0.14 m² of public green space per inhabitant. The city center (older neighborhoods) has a ratio of 0.44 m² per inhabitant, while the outskirts (newer neighborhoods) show only 0.06 m² per inhabitant. These figures remain significantly below WHO recommendations. Residents mainly use these green spaces for rest, benefiting from the shade they provide. These findings will help guide the development policy for green spaces in Cocody.

Field Guide: Morphometric Visualization and Characterization of Selected Foodborne Pathogens Using Advanced Imaging Techniques

This paper aims to present the phenotypic characteristics, such as length, width, circular diameter, volume, surface area to cross-sectional area ratio, surface uniformity, and surface texture, of the foodborne pathogens Salmonella enterica serovar Agona, Salmonella enterica serovar Enteritidis, Listeria monocytogenes, and Campylobacter jejuni. It is a novel “field-guide” presentation of the observable morphological characteristics of these four species in the form of a Dichotomous Key. Phenotypic values of the pathogens were measured using a high-accuracy, nano-level-resolution 3D laser confocal scanning microscope. All samples were fixed with glutaraldehyde and stained with methylene blue, ensuring morphological preservation. The images of the pathogens were captured under various imaging modes, including 3D, laser, and transmission electron microscopy resolutions. Results show that these pathogens exhibit distinct morphological and surface properties, with Campylobacter jejuni showing unique features. The dichotomous key shows a simplified way of classifying selected foodborne pathogens from their morphometric properties. The morphometric measurements, in many instances first reported in the literature, and images provide a readily observable way to identify and classify microorganisms, allowing researchers to potentially study evolutionary relationships, assess species diversity, and understand how organisms interact with their environment, especially when genetic information is limited or difficult to obtain.

Does Multidimensional Urban Morphology Affect Thermal Sensation? Evidence from Shanghai

The inappropriate thermal conditions resulting from increasingly severe climate issues have led to numerous complications for urban residents, decreased urban settlement comfort, and increased average and peak energy demands in built environments. Existing studies have demonstrated the significant influence of urban morphology (UM) on the urban thermal environment (UTE); however, at the meso-scale and macro-scale, UTE is often simplified to land surface temperature (LST) and building surface temperatures. To investigate the impact of UM on UTE, we developed an evaluation framework consisting of thermal sensing feedback (TSF) and LST. We employed the seven-level TSF scale to evaluate TSF data obtained from the Internet, emphasizing individualized thermal perceptions of urban spaces and reorienting UTE research towards a human-centric perspective. Using a regression model, we examined the relationships between two-dimensional and three-dimensional UM variables and UTE at the meso-scale in the central urban area of Shanghai, China, during August and December 2024. The results indicated the following: (1) The normalized difference vegetation index (NDVI), building density (BD), floor area ratio (FAR), impervious surface index (ISI), building height (BH), average building volume (ABV), sky view fraction (SVF), and building shape (BSsh) effectively explained TSF. However, area weighted mean shape index (SHAPEAM), aggregation index (AI), edge density (ED), elevation, building spacing (BSsp), and spatial congestion degree (SCD) showed no significant correlation with TSF. (2) Significant variables, including NDVI, FAR, ISI, UM, BD, and BH, exhibited opposite effects on cold perception in winter compared to heat perception in summer, indicating a consistent influence on thermal perception across seasons. (3) In summer, the significant variables SVF, BSsh, and ISI showed opposite effects on TSF and LST, while in winter, FAR demonstrated contrasting impacts on TSF and LST. The results of this study advance understanding of the mechanisms through which UM influences UTE, providing valuable insights for the development of sustainable, thermally comfortable urban environments.

Urban Spatial Management and Planning Based on the Interactions Between Ecosystem Services: A Case Study of the Beijing–Tianjin–Hebei Urban Agglomeration

Understanding the intricate relationships among ecosystem services (ESs) and clarifying their driving factors are essential prerequisites for establishing effective ecosystem management strategies. Therefore, we plotted the spatial-temporal distribution of five ESs in the Beijing-Tianjin-Hebei (BTH) urban agglomeration and analyzed their interactions in terms of trade-offs, synergies, and bundles. We identified the primary drivers impacting ESs and proposed recommendations for urban spatial management and planning. The result revealed that (1) between 2000 and 2020, the supply of soil conservation increased the most, by 52.56%, and habitat quality decreased the most, by 6.92%; (2) four ES pairs were synergies and six ES pairs exhibited trade-offs, with three ES pairs showing decreased synergies and two ES pairs showing increased trade-offs; (3) the main factors influencing the driving forces of ESs were precipitation, cropland area ratio, and forest area ratio; and (4) the spatial-temporal analysis of ES interactions determined that ESs exhibiting decreasing synergies should be prioritized in ecosystem management, suggesting that the spatial planning of ecosystems should be based on ES bundles. Thus, this study provides guidance for regional ecosystem spatial planning and management.

Molecular mechanisms underlying the testicular developmental variations among different lines of Tianfu Nonghua duck.

Molecular mechanisms underlying the testicular developmental variations among different lines of Tianfu Nonghua duck.

In vitro development of a radicular cyst: A morphological investigation of a spheroid cyst-like model associated with fibroblasts.

In vitro development of a radicular cyst: A morphological investigation of a spheroid cyst-like model associated with fibroblasts.

Effects of Botulinum Toxin A on Condylar Subchondral Bone Mass.

The management of temporomandibular disorders (TMD) remains challenging, with its underlying pathological mechanisms requiring further investigation. This study aimed to explore the effects of Botulinum Toxin A (Botox A) on the lateral pterygoid (LP) muscle and its impact on condylar subchondral bone mass. Rats were randomly assigned to either an experimental group (injected with Botox A) or a control group (injected with an equal volume of 0.9% normal saline). All rats were sacrificed at 2-, 4-, 8-, or 12-weeks post-injection. The right condyles were harvested and analyzed using Micro-computed tomography (CT) scanning and hematoxylin-eosin staining to evaluate changes in the condylar subchondral bone. Osteoclast activity in the subchondral bone was assessed via tartrate-resistant acid phosphatase (TRAP) staining. The activities of osteoclasts and osteoblasts in subchondral bone were detected by western blotting. At 2-weeks post-Botox A injection, the trabecular number (Tb.N) was significantly lower (p < 0.01). At 2- and 4-weeks, bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) were significantly lower (p < 0.05), while trabecular space (Tb.SP) and the ratio of bone surface area to bone volume (BS/BV) were significantly increased in the experimental group compared to control group (p < 0.05). At 8-weeks, BS/BV remained significantly elevated (p < 0.05), but no significant differences were observed in Tb.N, Tb.Th, BV/TV, or Tb.Sp at 8- and 12- weeks. Osteoclast numbers in the condylar subchondral bone were significantly higher in the Botox A group at 2-, 4-, and 8-weeks compared to the control group (p < 0.05). Additionally, protein expression levels of osteocalcin (OCN) and type I collagen (COL1A1) were markedly increased in the experimental group at 8- and 12-weeks (p < 0.05). Botox A induces a significant reduction in condylar subchondral bone mass in rats during the early post-injection period, with subsequent time-dependent recovery.