Nitroaromatic compounds (NACs) are components of munitions commonly found as soil contaminants at military training sites and elsewhere. These compounds pose possible threats to human health and ecological systems. Recent studies indicate that these compounds are strongly retained by smectite clays. The adsorption mechanisms are not fully reconciled, but it is known that the type of exchangeable cation strongly affects NAC affinity for smectites. This study examined the sorption of 1,3-dinitrobenzene, 2,4-dinitrotoluene and naphthalene from water by a smectite clay (SWy-2) saturated with ammonium, tetramethylammonium (TMA), trimethylphenylammonium (TMPA) and hexadecyltrimethylammonium (HDTMA). In all cases, we observed greater sorption of 2,4-dinitrotoluene compared with 1,3-dinitrobenzene. The sorption isotherms for 2,4-dinitrotoluene and 1,3-dinitrobenzene displayed a concave-downward curve for NH4-SWy-2 and TMA-SWy-2, whereas the isotherms for sorption of HDTMA-SWy-2 and TMPA-SWy-2 were essentially linear. The magnitude of sorption followed the order: NH4-SWy-2 > TMA-SWy-2 > TMPA-SWy-2 > HDTMA-SWy-2 for both compounds. The greater affinity of NACs for NH4- and TMA-SWy-2 is due in part to complex formation between the exchangeable cation and −NO2 groups. These clays also provide near optimal interlayer distances that approximate the molecular thickness of NACs hence promoting the simultaneous interaction of the planar aromatic rings with opposing siloxane surfaces and solute dehydration. Both processes are energetically favorable. In HDTMA-SWy-2, sorption of all solutes is via a partition-dominated process. Solute competition (diminished uptake of one solute in the presence of a second) was observed for TMA-SWy-2 but not HDTMA-SWy-2. This is consistent with an adsorptive mechanism for TMA-SWy-2 and a partitioning mechanism for HDTMA-SWy-2. This study demonstrates that the dominant molecular mechanism of NAC sorption by smectite changes fundamentally from complexation between −NO2 groups and the exchangeable cation (viz. NH4 and TMA) to partitioning for a systematic series of ammonium and quaternary ammonium cations in which the locus of positive charge (the central N atom) is progressively shielded by organic moieties of increasing size.

The U.S. Department of Agriculture–Agricultural Research Service (USDA-ARS) has been a leader in weed science research covering topics ranging from the development and use of integrated weed management (IWM) tactics to basic mechanistic studies, including biotic resistance of desirable plant communities and herbicide resistance. ARS weed scientists have worked in agricultural and natural ecosystems, including agronomic and horticultural crops, pastures, forests, wild lands, aquatic habitats, wetlands, and riparian areas. Through strong partnerships with academia, state agencies, private industry, and numerous federal programs, ARS weed scientists have made contributions to discoveries in the newest fields of robotics and genetics, as well as the traditional and fundamental subjects of weed–crop competition and physiology and integration of weed control tactics and practices. Weed science at ARS is often overshadowed by other research topics; thus, few are aware of the long history of ARS weed science and its important contributions. This review is the result of a symposium held at the Weed Science Society of America’s 62nd Annual Meeting in 2022 that included 10 separate presentations in a virtual Weed Science Webinar Series. The overarching themes of management tactics (IWM, biological control, and automation), basic mechanisms (competition, invasive plant genetics, and herbicide resistance), and ecosystem impacts (invasive plant spread, climate change, conservation, and restoration) represent core ARS weed science research that is dynamic and efficacious and has been a significant component of the agency’s national and international efforts. This review highlights current studies and future directions that exemplify the science and collaborative relationships both within and outside ARS. Given the constraints of weeds and invasive plants on all aspects of food, feed, and fiber systems, there is an acknowledged need to face new challenges, including agriculture and natural resources sustainability, economic resilience and reliability, and societal health and well-being.

Herbicide resistance has been studied extensively in agronomic crops across North America but is rarely examined in vegetables. It is widely assumed that the limited number of registered herbicides combined with the adoption of diverse weed management strategies in most vegetable crops effectively inhibits the development of resistance. It is difficult to determine whether resistance is truly less common in vegetable crops or whether the lack of reported cases is due to the lack of resources focused on detection. This review highlights incidences of resistance that are thought to have arisen within vegetable crops. It also includes situations in which herbicide-resistant weeds were likely selected for within agronomic crops but became a problem when vegetables were grown in sequence or in adjacent fields. Occurrence of herbicide resistance can have severe consequences for vegetable growers, and resistance management plans should be adopted to limit selection pressure. This review also highlights resistance management techniques that should slow the development and spread of herbicide resistance in vegetable crops.

In March 2020, at the onset of the coronavirus disease 2019 (COVID-19) pandemic in the United States, the Southern California Extracorporeal Membrane Oxygenation (ECMO) Consortium was formed. The consortium included physicians and coordinators from the 4 ECMO centers in San Diego County. Guidelines were created to ensure that ECMO was delivered equitably and in a resource effective manner across the county during the pandemic. A biomedical ethicist reviewed the guidelines to ensure ECMO use would provide maximal community benefit of this limited resource. The San Diego County Health and Human Services Agency further incorporated the guidelines into its plans for the allocation of scarce resources. The consortium held weekly video conferences to review countywide ECMO capacity (including census and staffing), share data, and discuss clinical practices and difficult cases. Equipment exchanges between ECMO centers maximized regional capacity. From March 1 to November 30, 2020, consortium participants placed 97 patients on ECMO. No eligible patients were denied ECMO due to lack of resources or capacity. The Southern California ECMO Consortium may serve as a model for other communities seeking to optimize ECMO resources during the current COVID-19 or future pandemics.

Although we see much utility in Osiurak and Reynaud's in-depth discussion on the role of what they term technical reasoning in cumulative culture, we argue that they neglect the time and energy costs that individuals would have to face to acquire skills in the absence of specific socio-cognitive abilities.

What promised to be a refreshing addition to cumulative cultural evolution, by moving the focus from cultural transmission to technological innovation, falls flat through a lack of thoroughness, explanatory power, and data. A comprehensive theory of cumulative cultural change must carefully integrate all existing evidence in a cohesive multi-level account. We argue that the manuscript fails to do so convincingly.

Five marsupial species are recognized from the Brule Formation at two localities in southwestern North Dakota: Fitterer Ranch and Obritsch Ranch (middle Oligocene; Whitneyan North American Land Mammal Age [NALMA]). The herpetotheriids Herpetotherium fugax Cope, 1873a, Copedelphys superstes new species, and the peradectid Nanodelphys hunti (Cope, 1873b) are represented at both localities. A fourth species is H. sp., cf. H. merriami (Stock and Furlong, 1922), represented by a single specimen from Fitterer Ranch, being limited elsewhere to the later Arikareean NALMA. A fifth species is represented by two isolated lower cheek teeth, interpreted as m1s, from Fitterer Ranch that are unique in lacking a trigonid (only two cusps present) while having a well-developed talonid. These specimens are referred to an indeterminate herpetotheriine species. The new species of Copedelphys is distinct from other species of the genus in that the anterior two lower molars are enlarged relative to the posterior molars. Overall, this new species is more similar in proportions to the latest Eocene (Chadronian) C. titanelix (Matthew, 1903) than the Oligocene (Orellan and Whitneyan) C. stevensoni (Cope, 1873b). This study adds a third and fourth Whitneyan marsupial fauna from the Great Plains region of North America, increases the known diversity of Whitneyan marsupials, and provides further evidence that marsupial diversity during the late Paleogene in North America was relatively stable until the late early Arikareean NALMA.

UUID: http://zoobank.org/b8534802-b9ed-4120-baca-fc72917f7d6a

Engagement of frontline staff, along with senior leadership, in competition-style healthcare-associated infection reduction efforts, combined with electronic clinical decision support tools, appeared to reduce antibiotic regimen initiations for urinary tract infections (P = .01). Mean monthly standardized infection and device utilization ratios also decreased (P < .003 and P < .0001, respectively).