Texas A&M University – Corpus Christi
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Direct observation and identification of nanoplastics in ocean water
No full textMillions of tons of plastics enter the oceans yearly, and they can be fragmented by ultraviolet and mechanical means into nanoplastics. Here, we report the direct observation of nanoplastics in global ocean water leveraging a unique shrinking surface bubble deposition (SSBD) technique. SSBD involves optically heating plasmonic nanoparticles to form a surface bubble and leveraging the Marangoni flow to concentrate suspended nanoplastics onto the surface, allowing direct visualization using electron microscopy. With the plasmonic nanoparticles co-deposited in SSBD, the surface-enhanced Raman spectroscopy effect is enabled for direct chemical identification of trace amounts of nanoplastics. In the water samples from two oceans, we observed nanoplastics made of nylon, polystyrene, and polyethylene terephthalate—all common in daily consumables. The plastic particles have diverse morphologies, such as nanofibers, nanoflakes, and ball-stick nanostructures. These nanoplastics may profoundly affect marine organisms, and our results can provide critical information for appropriately designing their toxicity studies.T.L., S.M., Q.Z., and R.Z. would like to thank the support from the U.S. National Science Foundation (1931850, 2040565, and 2001079) and the Center for the Advancement of Science in Space (GA-2018-268). W.X. is supported by NSF (1903719 and 1943431) and NIH (R15ES030955). The research vessel (R/V) Pelican was used for deep ocean water collection from the Gulf of Mexico. The usage of R/V Pelican was supported by X. Hu’s (TAMU-Corpus Christi) research grant from the National Oceanic and Atmospheric Administration (NA19OAR0170354). We thank N. Gan, M. Merrill, M. Brzezinski, C. Haley, S. Marbach, Y. Pang, F. Li, X. Jia, H. Moon, and S. Park (UNIST) for assistance in collecting water samples, and K. Hendricks for reading the manuscript. We also appreciate the partial support from the Notre Dame Integrated Imaging Facility and Materials Characterization Facility. We would also like to thank the support from the Open Access Publication Fund from the library and College of Science at TAMU-CC
Vulnerability of Wetlands due to Projected Sea-Level Rise in the Coastal Plains of the South and Southeast United States
No full textCoastal wetlands are vulnerable to accelerated sea-level rise, yet knowledge about their extent and distribution is often limited. We developed a land cover classification of wetlands in the coastal plains of the southern United States along the Gulf of Mexico (Texas, Louisiana, Mississippi, Alabama, and Florida) using 6161 very-high (2 m per pixel) resolution WorldView-2 and WorldView-3 satellite images from 2012 to 2015. Area extent estimations were obtained for the following vegetated classes: marsh, scrub, grass, forested upland, and forested wetland, located in elevation brackets between 0 and 10 m above sea level at 0.1 m intervals. Sea-level trends were estimated for each coastal state using tide gauge data collected over the period 1983–2021 and projected for 2100 using the trend estimated over that period. These trends were considered conservative, as sea level rise in the region accelerated between 2010 and 2021. Estimated losses in vegetation area due to sea level rise by 2100 are projected to be at least 12,587 km2, of which 3224 km2 would be coastal wetlands. Louisiana is expected to suffer the largest losses in vegetation (80%) and coastal wetlands (75%) by 2100. Such high-resolution coastal mapping products help to guide adaptation plans in the region, including planning for wetland conservation and coastal development
Advanced computer architecture
No full textIntroduction: What is Computer Architecture? The science and art of designing, structuring, and optimizing the core components of a computer system. Defines how instructions are processed, data is accessed, and system components communicate. Acts as the bridge between the software (instructions) and hardware (physical components). Provides a foundation for understanding the trade-offs between performance, power consumption, and cost in advanced systems. Enables an in-depth analysis of advanced techniques like pipelining, superscalar execution, and memory hierarchies. Forms the basis for optimizing software for specific architectures and exploiting their capabilities. Helps in appreciating the challenges and opportunities presented by emerging technologies like multicore processors and GPUs
Fundamentals of computer design: Advanced computer architecture
No full textIntroduction: In this topic, we will explore: What is Computer Design, Historical Context, Key considerations that go into creating efficient & powerful computer system
The impact of digitalized community-based squarestepping exercise program on cognitive and balance functions among older adults living in senior facilities: A pilot study
No full textObjectives: Older adults exhibit a high desire for active and healthy aging without physical or mental dysfunction, particularly those living independently in senior facilities. Preserving or improving cognitive function and minimizing fall risks are essential for older adults to live a happy and active lifestyle. The purpose of this pilot study was to examine the feasibility, safety, and preliminary effectiveness of the innovative digitalized community-based square-stepping exercise program (DC-SSEP) in improving cognitive and physical function among older adults residing in senior facilities.
Methods: Guided by the Health Promotion Model and Social Cognitive Theory, this pilot study used a quasi-experiment design with one intervention group. A total of 17 older adults recruited from a senior facility in Southern Texas participated in 40 sessions of DC-SSEP over 20 weeks. Cognitive function was measured using the latest version (8.1) of Montreal Cognitive Assessment and the balance function focusing on balance and functional mobility was measured using Berg Balance Scale and Time to Up and Go.
Results: Most participants were non-Hispanic white women. The DC-SSEP was a feasible and safe exercise program for older adults living in senior facilities; and the results showed the preliminary effectiveness of the DC-SSEP in improving cognitive and balance function (P < 0.01) among older adults.
Conclusion: This pilot study is distinctive as it is among the first to evaluate the multi-layered impacts of DC-SSEP using Internet of Things (IoT) technology and integrated operating software in the United States. Despite the small sample size and homogeneity of participants, this pilot study suggests multiple valuable directions for future research using DC-SSEP.This study was supported by the Texas Comprehensive Research Fund from Texas A&M University, Corpus Christi (TCRF-09/2022; grant number # 143403-00140)
Cellular response of keratinocytes to the entry and accumulation of nanoplastic particles
No full textPlastic accumulation in the environment is rapidly increasing, and nanoplastics (NP), byproducts of environmental weathering of bulk plastic waste, pose a significant public health risk. Particles may enter the human body through many possible routes such as ingestion, inhalation, and skin absorption. However, studies on NP penetration and accumulation in human skin are limited. Loss or reduction of the keratinized skin barrier may enhance the skin penetration of NPs. The present study investigated the entry of NPs into a human skin system modeling skin with compromised barrier functions and cellular responses to the intracellular accumulations of NPs. Two in vitro models were employed to simulate human skin lacking keratinized barriers. The first model was an ex vivo human skin culture with the keratinized dermal layer (stratum corneum) removed. The second model was a 3D keratinocyte/ dermal fibroblast cell co-culture model with stratified keratinocytes on the top and a monolayer of skin fibroblast cells co-cultured at the bottom. The penetration and accumulation of the NPs in different cell types were observed
using fluorescent microscopy, confocal microscopy, and cryogenic electron microscopy (cryo-EM). The cellular responses of keratinocytes and dermal fibroblast cells to stress induced by NPs stress were measured. The genetic regulatory pathway of keratinocytes to the intracellular NPs was identified using transcript analyses and KEGG pathway analysis. The cellular uptake of NPs by skin cells was confirmed by imaging analyses. Transepidermal transport and penetration of NPs through the skin epidermis were observed. According to the gene expression and pathway analyses, an IL-17 signaling pathway was identified as the trigger for cellular responses to internal NP accumulation in the keratinocytes. The transepidermal NPs were also found in co-cultured dermal fibroblast cells and resulted in a large-scale transition from fibroblast cells to myofibroblast cells with enhanced production of α-smooth muscle actin and pro-Collagen Ia. The upregulation of inflammatory factors and cell activation may result in skin inflammation and ultimately trigger immune responses.The study was supported by NIH (R15ES030955) and Harte Research Institute Fellowship
Interpreting biogeochemical processes through the relationship between total alkalinity and dissolved inorganic carbon: Theoretical basis and limitations
No full textThe marine carbonate system is influenced by anthropogenic CO2 uptake, biogeochemical processes, and physical changes that involve freshwater input and removal. Two frequently used parameters to quantify seawater carbonate system are total alkalinity (TA) and total dissolved inorganic carbon (DIC). To account for the physical changes, both TA and DIC are usually normalized to a reference salinity (i.e., nTA and nDIC), and then the relationship between nTA and nDIC is used to identify major biogeochemical processes that regulate the carbonate system, based on process-specific reaction stoichiometry. However, the theoretical basis of this interpretation has not been holistically examined. In this study, we validated this method under idealized conditions and discussed the associated assumptions and limitations. Furthermore, we applied this method to interpret field TA and DIC data from a lagoonal estuary in the northwestern Gulf of Mexico. Our results demonstrated that evaluating field data that encompass multiple stations and time periods could be problematic. In addition, various combinations of biogeochemical processes can lead to the same nTA–nDIC relationship, even though the relative importance of each individual process may vary significantly. Therefore, the stoichiometric relationship relying solely on TA and DIC data is not a definitive approach for uncovering dominant biogeochemical processes. Instead, measurements of process-specific parameters are necessary
Senator Truan and governor of Massachusetts, Michael Dukakis
No full textSenator Carlos Truan and Michael Dukakis pose for a photograph
Size matters? Penis dissatisfaction and gun ownership in America
No full textIn this study, we formally examine the association between penis size dissatisfaction and gun ownership in America. The primary hypothesis, derived from the psychosexual theory of gun ownership, asserts that men who are more dissatisfied with the size of their penises will be more likely to personally own guns. To test this hypothesis, we used data collected from the 2023 Masculinity, Sexual Health, and Politics (MSHAP) survey, a national probability sample of 1,840 men, and regression analyses to model personal gun ownership as a function of penis size dissatisfaction, experiences with penis enlargement, social desirability, masculinity, body mass, mental health, and a range of sociodemographic characteristics. We find that men who are more dissatisfied with the size of their penises are less likely to personally own guns across outcomes, including any gun ownership, military-style rifle ownership, and total number of guns owned. The inverse association between penis size dissatisfaction and gun ownership is linear; however, the association is weakest among men ages 60 and older. With these findings in mind, we failed to observe any differences in personal gun ownership between men who have and have not attempted penis enlargement. To our knowledge, this is the first study to formally examine the association between penis size and personal gun ownership in America. Our findings fail to support the psychosexual theory of gun ownership. Alternative theories are posited for the apparent inverse association between penis size dissatisfaction and personal gun ownership, including higher levels of testosterone and constructionist explanations.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The data collection for this study was supported by funding from Change The Ref, an organization that ‘‘uses urban art and nonviolent creative confrontation to expose the disastrous effects of the mass shooting pandemic.’’ Although Change The Ref holds a clear political stance with respect to the role of guns in society, this organization played no part in the planning or implementation of the study
Enhanced removal of ultratrace levels of gold from wastewater using sulfur-rich covalent organic frameworks
No full textIn view of the increasing global demand and consumption of gold, there is a growing need and effort to extract gold from alternative sources besides conventional mining, e.g., from water. This drive is mainly due to the potential benefits for the economy and the environment as these sources contain large quantities of the precious metal that can be utilized. Wastewater is one of these valuable sources in which the gold concentration can be in the ppb range. However, the effective selective recovery and recycling of ultratrace amounts of this metal remain a challenge. In this article, we describe the development of a covalent imine based organic framework with pores containing thioanisole functional groups (TTASDFPs) formed by the condensation of a triazine-based triamine and an aromatic dialdehyde. The sulfur-functionalized pores served as effective chelating agents to bind Au3+ ions, as evidenced by the uptake of more than 99% of the 9 ppm Au3+ solution within 2 min. This is relatively fast kinetics compared with other adsorbents reported for gold adsorption. TTASDFP also showed a high removal capacity of 245 mg·g−1 and a clear selectivity toward gold ions. More importantly, the material can capture gold at concentrations as low as 1 ppb.This work was supported by New York University Abu Dhabi and the NYUAD Water Research Center, funded by Tamkeen under the NYUAD Research Institute Award (Project CG007). We thank NYUAD for their generous support for the research program. We also thank Sandooq Al Watan (Grant No. SWARD-S22-014; Project ID, PRJ-SWARD-628) for their generous support. The research work was carried out by using the Core Technology Platform resources at NYUAD. We acknowledge Graphic Designer Aisha Jrad, who made the abstract and Table of Contents (TOC) artwork of the manuscript ([email protected])