Month: August 2024

Performance ranking of multiple CORDEX-SEA sensitivity experiments: towards an optimum choice of physical schemes for RegCM over Southeast Asia

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Abstract

This study conducted and evaluated 44 experiments using the non-hydrostatic version of the regional climate model RegCM4 (RegCM4-NH) and an additional three experiments with RegCM version 5 (RegCM5) over Southeast Asia for the period 2010–2015. The initiative was part of the coordinated regional climate downscaling experiment—Southeast Asia (CORDEX-SEA) project, in preparation for downscaling the latest coupled model intercomparison project Phase 6 (CMIP6) global climate models (GCMs). The RegCM4-NH experiments, forced by the ERA5 reanalysis, were configured using combinations of four cumulus, three planetary boundary layer (PBL), and three explicit moisture schemes. The spatiotemporal variability of simulated 2 m-temperature and rainfall for 2010–2015 was evaluated against observational datasets. The best experiments demonstrated reasonable reproduction of observed annual cycles and spatial distribution, while many exhibited unrealistic biases. A score ranking system was implemented to objectively compare the performance of experiments, enabling the identification of top-ranked experiments for Southeast Asia. The ensemble mean of the 44 RegCM4-NH experiments exhibited commendable performance, ranking 11th overall. Furthermore, the three additional RegCM5 experiments did not yield improved results compared to RegCM4-NH under the same physical configuration, suggesting that opting for RegCM4-NH would be a prudent choice for the CORDEX-SEA community in the forthcoming CMIP6 downscaling cycle for Southeast Asia.

Population genetics of caribou in the Alaska-Yukon border region: implications for designation of conservation units and small herd persistence

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Abstract

Better knowledge of genetic relationships between the Fortymile caribou herd and its neighbors is needed for conservation decision-making in Canada. Here, we contribute the first fine-scale analysis of genetic population structure in nine contiguous caribou herds at the geographic boundaries between Barren-ground and Northern Mountain caribou, and at the Alaska-Yukon border. Using pairwise differentiation metrics, STRUCTURE, and discriminant analysis of principal components (DAPC) to analyze 15 microsatellite loci in 379 caribou, we found complex patterns of genetic differentiation. The Fortymile was the only herd assigned to more than one genetic cluster, indicative of its history as a larger herd whose range expansions and gene flow to other herds were likely important to maintaining diversity across a functioning genetic metapopulation. Some small herds (Chisana, Klaza, and White Mountains) were genetically distinct, while others (Hart River, Clear Creek, Mentasta) exhibited little differentiation from herds they occasionally overlap, including herds assigned to different conservation units (DUs). This genetic connectivity does not result from demographic connectivity, as episodic contact during rut, rather than herd switching, is the likely mechanism. Unusually, one small herd (White Mountains) maintained genetic differentiation despite rut overlap with Fortymile. Our data reveal that some herds with different ecological and behavioral attributes are demographically independent but nonetheless genetically connected. Thus, we suggest that managing caribou for an appropriate level of genetic connectivity, while also supporting herd persistence, will be essential to conserve caribou genetic diversity in the region.

Hidden Histories of Captive and Enslaved Maya Women in the Indigenous Americas

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Abstract

Few archaeological studies of Pre-Columbian Maya peoples mention enslaved individuals. While ethnohistoric texts attest to the likelihood of Indigenous Maya enslavement practices before the arrival of Spanish conquistadores and friars, archaeologists are reluctant to consider such practices and peoples into interpretative frameworks because of their tremendous ambiguity in the archaeological record. This paper embraces and probes the ambiguity of the archaeological record to interrogate the possibility of hidden histories of captive and enslaved Maya individuals in general and captive and enslaved Maya women in particular during the Classic and Postclassic periods. It argues that such women cannot be found in particular types of artifacts or hieroglyphic texts but at the intersection of names and landscapes.

Tropical mobola plum (Parinari Curatellifolia): a full characterization of wood and bark within the scope of biorefineries

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Abstract

Parinari curatellifolia is the main species used to produce charcoal in Angola. Its chemical, anatomical, and thermal properties were analyzed. The bark is dark grey, rough, and corky, and the wood is brown to yellow-red. Compared to wood, bark fibers presented lower length, lumen, and wall thickness. There is not much difference between height and cell numbers of rays. Sieve tube elements appear solitary or in small groups (2–3 cells), and vessels were of two diameter classes but diffuse-porous. Bark basic density was lower than wood (505 kg.m− 3vs. 580 kg.m− 3). The mean chemical composition from bark vs. wood of P. curatellifolia was ash (3.2% vs. 1.6%), total extractives (12.2% vs. 10.0%), total lignin (42.4% vs. 28.4%), and suberin 5.4%. Families identified by GC-MS from DCM extracts were predominated by fatty acids in wood and triterpenoid contents in bark. Bark and wood had higher antioxidant activity in FRAP and DPPH methods. The bark had a monomeric lignin composition richer in guaiacyl-units (25.9% vs. 22.5%) and lower syringyl-units (5.7% vs. 8.5%). Potassium was the most abundant mineral, while the least was cadmium found in wood and bark. Regarding thermal properties, bark presented higher moisture content (9.0% vs. 8.0%), ash (3.33% vs. 1.61%), total volatiles (27.5% vs. 20.7%), lower fixed carbon (69.1% vs. 77.7%) and higher heating value (20.9 MJ/kg vs. 19.1 MJ/kg). According to these characteristics, both biomasses are interesting for developing more value-added products (e.g., charcoal, bio-chemicals with phytochemistry and pharmacology activities) besides burning under the context of biorefineries.

Complex background segmentation for noncontact cable vibration frequency estimation using semantic segmentation and complexity pursuit algorithm

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Abstract

This paper proposes a new complex background segmentation method based on the modified fully convolutional network semantic segmentation for noncontact cable vibration frequency estimation. The estimation of frequency from video data is challenged by the presence of background object motion, which directly impacts the accuracy of the video-based method. To address this issue, image tests were carried out among the existing model (U2-Net) to explore the effect of the efficient channel attention (ECA) and convolutional block attention module (CBAM) on cable segmentation performance. As a result, a relative optimal model was identified. This modified model was then used to remove the complex background, while retaining the vibration signals specific to the cable. Subsequently, phase matrices encoding cable vibration were calculated using a phase-based motion estimation algorithm at various cable locations. The modal response of the cable vibration was estimated using the complexity pursuit (CP) algorithm from the segmented video. Finally, the vibration frequency of the cable was estimated. The proposed method was validated on a small-scale cable model. The results are in good agreement with the values sampled by the accelerometer, with an average relative error of 4.50%. This estimation shows the significant potential of the proposed method in structural health monitoring.

A three-stage detection algorithm for automatic crack-width identification of fine concrete cracks

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Abstract

Semantic image segmentation is extensively used for automatic concrete crack detection. In previous studies on semantic image segmentation, concrete images were usually labeled as crack and noncrack zones, and recognition models were then trained using artificial neural networks. However, there is not enough edge information in concrete images for the trained model to identify effectively fine concrete cracks (widths < 0.1 mm). Furthermore, complex backgrounds in concrete images can cause false detections. To improve efficiency and reduce false detections, this study develops a three-stage automatic crack-width identification method for fine concrete cracks. First, a full crack skeleton information identification based on image segmentation is proposed. The performance of the mainstream image segmentation architectures, PSP-Net, Seg-Net, U-Net, and Res-Unet, are compared and analyzed, demonstrating that the Res-Unet-based crack skeleton segmentation is the most accurate at fine-crack detection and able to solve the information loss problem that occurs when learning the imbalanced data of fine concrete cracks. Second, a fractal dimension (FD)-based false detection removal process is applied to discriminate true cracks and false detections. The results show that false detections (line-like curves, shadows, and surface stains) can be removed, increasing the matching rate from 0.6476 to 0.8351. Finally, the FD features of the crack skeleton with maximum widths < 0.1 mm, crack widths in the range of 0.1–0.2 mm, and crack widths > 0.2 mm are calculated. Findings illustrate that the values of the FD feature for the three crack-width ranges are suitable for quantitative characterization of identified crack widths.

Symbiosexuality: A Review of Discourses of Attraction to the “Third Force” Created by People in Relationships

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Abstract

Symbiosexuality, the individual experience of attraction to people in relationships, has not been examined as a lived experience. Lack of recognition and examination of symbiosexuality is surprising when one considers studies of romantic and sexual desires and behaviors associated with more than two people. Also evident in the existence of the sexual identity label known as the unicorn and easily found in essays, memoirs, and dating apps, this attraction proves salient. Further, we find evidence of symbiosexuality outside Western discourses on desire and sexuality. Dominant conceptions and assumptions about sexuality and desire including mononormativity, respectability politics within polyamorous communities, and current conceptions of desire within western discourse contribute to symbiosexual invisibility. This invisibility harms several sexual minority groups, especially women and gender minorities within these groups. The purpose of this review is to describe and provide evidence of the phenomenon of symbiosexuality. Through a queer-feminist lens, I argue that recognition of symbiosexuality will fill a knowledge gap in the field of sexuality studies on the nature and shape of human sexual attractions and may be validating and/or empowering to those experiencing these types of attractions.

A Cross-Sectional Comparative Study Analyzing the Quality of YouTube Videos as a Source of Information for Treatment of Erectile Dysfunction in English and Hindi Language

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Abstract

This study aimed to evaluate and compare the quality of information in YouTube videos on erectile dysfunction (ED) treatment in English and Hindi language. The English and Hindi terms for erectile dysfunction treatment were searched on YouTube, and the first 100 videos were screened. Of them, 148 videos were eligible for analysis. Quality of health information was assessed using: a modified 5-item DISCERN tool; and the Patient Education Materials Assessment Tool (PEMAT) for Audio/Visual Materials. The analyzed videos had cumulative views of more than 70 million. Only 8.8% of videos had DISCERN score ≥ 4 indicating good content quality. About 46% and 40% of videos presented information in an easy-to-understand and actionable manner based on PEMAT sub-scale scores ≥ 70% respectively. The three most common treatments suggested for ED were lifestyle modification-based advice (41.2%), oral Phosphodiesterase type-5 inhibitors (37.8%), and penile prosthetic implantation (28.4%).Herbal/ over-the-counter medicines, and specific diet/ food item(s) were more frequently suggested in Hindi videos. Whereas, intra-cavernosal injections, MUSE suppositories, and shock wave therapy were more commonly suggested in English videos. A substantial number of videos suggested treatment strategies that were not concordant with the American Urological Association guidelines. Healthcare professionals need to be mindful of this while counseling patients and advocate for the creation of more reliable and accurate online sources of information in English and other vernacular languages like Hindi.

Estimation of industry-level productivity with cross-sectional dependence by using spatial analysis

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Abstract

In this paper, we incorporate spatial analysis to estimate industry-level productivity in the presence of inter-sectoral linkages. Since each industry plays a role in providing intermediate goods to other sectors, the interdependence of economic activities across industries is inevitable. We exploit the linkage patterns from the input-output relationship to define cross-industry dependencies in economic space. We propose a spatial stochastic frontier model, which extends the stochastic frontier model to a spatially dependent specification. The models are estimated using quasi-maximum likelihood methods. Applying the approach to U.S. industry-level data from 1947 to 2010, we find that sectoral dependencies are the consequences of indirect effects via the supply chain network of industries resulting in larger output elasticities as well as scale effects for the networked production processes. However, productivity growth is estimated comparably across different spatial and non-spatial model specifications.

Thermal and imaging subsurface structure of Farasan and Dahlak Islands, southern Red Sea, derived from the interpretation of marine geophysical data

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Abstract

The Red Sea had inimitable geological ancient times and is considered a new ocean basin model. It has many islands of numerous sizes in the southern sector and a widespread group of shoals, such as Farasan (Saudi Arabia) and Dahlak (Eretria), due to its geological setting differences. In this work, a group of applications was used to provide a wider vision of the potential field, as well as to image the thermal and subsurface structures of the study area (Farasan and Dahlak Islands) using available marine potential field datasets (marine gravity and magnetic) and topographic and bathymetric datasets. These datasets were downloaded from the GEOSOFT server (Data sources: http://dap.geosoft.com/). We applied different filters of the marine potential field datasets data (e.g., horizontal gradient filter) to create a subsurface structure image. The horizontal gradient technique was used to locate density edges/boundaries from gravity data. The basement depth was displayed, as it was required during the Curie depth estimation by means of mathematical formulas. The profile ~ 500 km in length was selected to cross the study area and its surroundings so as to perform the joint 2D inversion modeling process. The results showed that the Farasan Islands have a shallower Curie point depth and basement relief than Dahlak Islands, indicating that both island groups were not isolated from each other but molded and formed independently. The results revealed that the islands’ different thermal systems were based on heat flow values calculated for each group.

Graphical abstract