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PREMISE: Reconstructing the light environment and architecture of the plant canopy from the fossil record requires the use of proxies, such as those derived from cell wall undulation, cell size, and carbon isotopes. All approaches assume that plant taxa will respond predictably to changes in light environments. However, most species-level studies looking at cell wall undulation only consider sun or shade leaves; therefore, we need a fully quantitative taxon-specific method. METHODS: We quantified the response of cell wall undulation, cell size, and carbon isotopes of Platanus occidentalis using two experimental setups: (1) two growth chambers at low and high light and (2) a series of outdoor growth experiments using green and black shade cloth at different densities. We then developed and applied a proxy for daily light integral (DLI) to fossil Platanites leaves from two early Paleocene floras from the San Juan Basin in New Mexico. RESULTS: All traits responded to light environment. Cell wall undulation was the most useful trait for reconstructing DLI in the geological record. Median reconstructed DLI from early Paleocene leaves was ~44 mol m-2  d-1 , with values from 28 to 54 mol m-2  d-1 . CONCLUSIONS: Cell wall undulation of P. occidentalis is a robust, quantifiable measurement of light environment that can be used to reconstruct the paleo-light environment from fossil leaves. The distribution of high DLI values from fossil leaves may provide information on canopy architecture; indicating that either (1) most of the canopy mass is within the upper portion of the crown or (2) leaves exposed to more sunlight are preferentially preserved.

Perceived lack of tools, and fears of the sensitivity of DNA data, should not be obstacles

Consumer uptake of direct-to-consumer (DTC) DNA ancestry testing is accelerating, yet few empirical studies have examined test impacts on recipients despite the DTC ancestry industry being two decades old. Participants in a longitudinal cohort study of response to health-related DTC genomic testing also received personal DNA ancestry testing at no additional cost. Baseline survey data from the primary study were analyzed together with responses to an additional follow-up survey focused on the response to ancestry results. Ancestry results were generated for 3466 individuals. Of those, 1317 accessed their results, and 322 individuals completed an ancestry response survey, in other words, approximately one in ten who received ancestry testing responded to the survey. Self-reported race/ethnicity was predictive of those most likely to view their results. While 46% of survey responders (N = 147) reported their ancestry results as surprising or unexpected, less than 1% (N = 3) were distressed by them. Importantly, however, 21% (N = 67) reported that their results reshaped their personal identity. Most (81%; N = 260) planned to share results with family, and 12% (N = 39) intended to share results with a healthcare provider. Many (61%; N = 196) reported test benefits (e.g., health insights), while 12% (N = 38) reported negative aspects (e.g., lack of utility). Over half (N = 162) reported being more likely to have other genetic tests in the future. DNA ancestry testing affected individuals with respect to personal identity, intentions to share genetic information with family and healthcare providers, and the likelihood to engage with other genetic tests in the future. These findings have implications for medical care and research, specifically, provider readiness to engage with genetic ancestry information.

Stanley asked whether a tree is determined up to isomorphism by its chromatic symmetric function. We approach Stanley's problem by studying the relationship between the chromatic symmetric function and other invariants. First, we prove Crew's conjecture that the chromatic symmetric function of a tree determines its generalized degree sequence, which enumerates vertex subsets by cardinality and the numbers of internal and external edges. Second, we prove that the restriction of the generalized degree sequence to subtrees contains exactly the same information as the subtree polynomial, which enumerates subtrees by cardinality and number of leaves. Third, we construct arbitrarily large families of trees sharing the same subtree polynomial, proving and generalizing a conjecture of Eisenstat and Gordon. [ABSTRACT FROM AUTHOR]

Researchers and practitioners are increasingly using machine‐generated synthetic data as a tool for advancing health science and practice, by expanding access to health data while—potentially—mitigating privacy and related ethical concerns around data sharing. While using synthetic data in this way holds promise, we argue that it also raises significant ethical, legal, and policy concerns, including persistent privacy and security problems, accuracy and reliability issues, worries about fairness and bias, and new regulatory challenges. The virtue of synthetic data is often understood to be its detachment from the data subjects whose measurement data is used to generate it. However, we argue that addressing the ethical issues synthetic data raises might require bringing data subjects back into the picture, finding ways that researchers and data subjects can be more meaningfully engaged in the construction and evaluation of datasets and in the creation of institutional safeguards that promote responsible use. [ABSTRACT FROM AUTHOR]

This study investigated improving the usability of a mainstream cell phone for use by individuals with low vision by providing a means to display the text of the keys in large print on the phone's screen. Two enlarging techniques (suspend and display and delay and display) were developed, and the programs were loaded into the cell phone. The experiment was divided into four stages. In each stage, the participants used a different dialing mode: (1) Control mode, in which dialing tasks were done as they would be if the phone had no special features, (2) Suspend-and-display training mode, (3) Delay-and-display training mode, initially set at two seconds and (4) Composite mode, in which the user had the option of using either enlargement technique or a combination of the techniques.

During July-September 2023, an outbreak of Shiga toxin-producing Escherichia coli O157:H7 illness among children in city A, Utah, caused 13 confirmed illnesses; seven patients were hospitalized, including two with hemolytic uremic syndrome. Local, state, and federal public health partners investigating the outbreak linked the illnesses to untreated, pressurized, municipal irrigation water (UPMIW) exposure in city A; 12 of 13 ill children reported playing in or drinking UPMIW. Clinical isolates were genetically highly related to one another and to environmental isolates from multiple locations within city A's UPMIW system. Microbial source tracking, a method to indicate possible contamination sources, identified birds and ruminants as potential sources of fecal contamination of UPMIW. Public health and city A officials issued multiple press releases regarding the outbreak reminding residents that UPMIW is not intended for drinking or recreation. Public education and UPMIW management and operations interventions, including assessing and mitigating potential contamination sources, covering UPMIW sources and reservoirs, indicating UPMIW lines and spigots with a designated color, and providing conspicuous signage to communicate risk and intended use might help prevent future UPMIW-associated illnesses. [ABSTRACT FROM AUTHOR]