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We develop the methods used by Rudnev and Wheeler (2022) to prove an incidence theorem between arbitrary sets of Möbius transformations and point sets in F p 2 . We also note some asymmetric incidence results, and give applications of these results to various problems in additive combinatorics and discrete geometry. For instance, we give an improvement to a result of Shkredov concerning the number of representations of a non-zero product defined by a set with small sum-set, and a version of Beck's theorem for Möbius transformations. [ABSTRACT FROM AUTHOR]

We study sources for torsion in Poincarè gauge theory in any dimension, signature, and spin. We find that symmetric kinetic terms for non-Yang–Mills bosonic fields of arbitrary rank drive torsion. Our detailed discussion of spin-3/2 Rarita–Schwinger fields shows that they source all independent parts of the torsion. We develop systematic notation for spin-(2k+1)/2 fields and find the spin tensor for arbitrary k in n ≥ 2k+1 dimensions. For k > 0 there is a novel direct coupling between torsion and spinor fields. We also cast the well-known gauge relation between the canonical and Belinfante–Rosenfield energy tensors in terms of different choices of independent variables. [ABSTRACT FROM AUTHOR]

We investigate the occurrence of naked singularities, local and global, in the incoming Vaidya spacetimes with zero initial mass. While it is well-known that these spacetimes admit locally and globally naked singularities, we demonstrate that globally naked singularities are significantly more common than is stressed in the literature, being generic in a natural topology on this collection of spacetimes. A heuristic consequence of the results is that the slow accumulation of mass is both necessary and sufficient for both types of naked singularity in these spacetimes. We demonstrate that the naked singularity, as long as it exists, always has divergent curvature (Kretschmann scalar) associated to it along emerging null curves, regardless of the form of the mass function. In particular, a consequence is that the curvature strength of the singularity cannot be smoothed away. [ABSTRACT FROM AUTHOR]

We find a large internal symmetry within 4-dimensional Poincarè gauge theory. In the Riemann-Cartan geometry of Poincaré gauge theory the field equation and geodesics are invariant under projective transformation, just as in affine geometry. However, in the Riemann-Cartan case the torsion and nonmetricity tensors change. By generalizing the Riemann-Cartan geometry to allow both torsion and nonmetricity while maintaining local Lorentz symmetry the difference of the antisymmetric part of the nonmetricity Q and the torsion T is a projectively invariant linear combination S = T - Q with the same symmetry as torsion. The structure equations may be written entirely in terms of S and the corresponding Riemann-Cartan curvature. The new description of the geometry has manifest projective and Lorentz symmetries, and vanishing nonmetricity. Torsion, S and Q lie in the vector space of vector-valued 2-forms. Within the extended geometry we define rotations with axis in the direction of S. These rotate both torsion and nonmetricity while leaving S invariant. In n dimensions and (p, q) signature this gives a large internal symmetry. The four dimensional case acquires SO(11,9) or Spin(11,9) internal symmetry, sufficient for the Standard Model. The most general action up to linearity in second derivatives of the solder form includes combinations quadratic in torsion and nonmetricity, torsion-nonmetricity couplings, and the Einstein-Hilbert action. Imposing projective invariance reduces this to dependence on S and curvature alone. The new internal symmetry decouples from gravity in agreement with the Coleman-Mandula theorem. [ABSTRACT FROM AUTHOR]

Predictive toxicity models, including interspecies correlation estimation (ICE) models, are reliable alternatives to animal toxicity testing. The ICE models describe mathematical relationships facilitating toxicity prediction from one surrogate test species to a species of unknown sensitivity. The ICE models were developed from curated aquatic toxicity data for 19 nonionic alcohol ethoxylate (AE) surfactants manufactured through the same process. Comparison of AE–ICE predictions with observed values from external validation datasets indicates a reasonable predictive accuracy. Model predictions were also closer to observed values than predictions from previously published ICE models for other substance groups. Comparison of acute fifth percentile hazard concentrations (HC5s) from species sensitivity distributions enhanced with AE–ICE predictions with chronic HC5s published elsewhere produced an acute‐to‐chronic ratio of 5, which was used to estimate chronic HC5s. With both acute and chronic HC5s for 14 AE substances, regressions were made relative to their respective liposome–water partitioning coefficients (log Klipw), resulting in HC5–log Klipw relationships useful in estimating HC5s for AE substances with known composition but with limited or unavailable toxicity data. The findings from this case study further demonstrate that ICE models are viable alternatives to toxicity testing and could be used as weight of evidence in hazard assessment evaluations. Environ Toxicol Chem 2021;40:2073–2082. © 2021 SETAC [ABSTRACT FROM AUTHOR]

We study the growth of product sets in some finite three-dimensional matrix groups. In particular, we prove two results about the group of 2 × 2 upper triangular matrices over arbitrary finite fields: a product set estimate using techniques from multiplicative combinatorics and an energy estimate using incidence geometry. The energy method gives better quantitative results but only applies to small sets. We also prove an energy result for the Heisenberg group. [ABSTRACT FROM AUTHOR]

Background and Aims The success of invasive plants can be attributed to many traits including the ability to adapt to variable environmental conditions. Whether by adaptation, acclimation or phenotypic plasticity, these plants often increase their resource-use efficiency and, consequently, their fitness. The goal of this study was to examine the hydraulic and eco-physiological attributes of sun and shade populations of Pteridium aquilinum , a weedy fern, to determine whether the presence of vessels and other hydraulic attributes affects its success under a variety of light conditions. Methods Hydraulic traits such as cavitation resistance, hydraulic conductivity, photosynthesis and water potential at turgor loss point were measured on fronds from sun and shade populations. Anatomical and structural traits such as conduit diameter and length, stomatal density and vein density were also recorded. Diurnal measures of leaf water potential and stomatal conductance complement these data. Key Results Gas exchange was nearly double in the sun plants, as was water-use efficiency, leaf-specific conductivity, and stomatal and vein density. This was largely achieved by a decrease in leaf area, coupled with higher xylem content. There was no significant difference in petiole cavitation resistance between the sun and shade leaves, nor in xylem-specific conductivity. Hydraulic conduit diameters were nearly equivalent in the two leaf types. Conclusions Shifts in leaf area and xylem content allow P. aquilinum to occupy habitats with full sun, and to adjust its physiology accordingly. High rates of photosynthesis explain in part the success of this fern in disturbed habitats, although no change was observed in intrinsic xylem qualities such as cavitation resistance or conduit length. This suggests that P. aquilinum is constrained by its fundamental body plan, in contrast to seed plants, which show greater capacity for hydraulic adjustment. [ABSTRACT FROM AUTHOR]

Objectives: (1) To develop an adaptation framework for MTM delivery for pharmacists (the MTM Adaptability Framework), (2) to examine the impact of an educational intervention informed by the MTM Adaptability Framework on MTM completion rates over a 2-year period, and (3) to explore pharmacists' perceptions regarding knowledge and beliefs about MTM and MTM implementation self-efficacy pre- and post-intervention.Methods: This study is a prospective, mixed-methods research study including a quasi-experimental, one-group pretest-posttest quantitative study with a sequential explanatory qualitative study arm featuring semi-structured key informant interviews. US supermarket pharmacy chain setting included 93 community pharmacy sites located in Tennessee, Kentucky, and Alabama. MTM completion rates are reported as percentage of completed comprehensive medication reviews (CMRs) and targeted medication reviews (TMRs) and pharmacist perceptions.Results: An 11.4% absolute increase in MTM completion rates was seen after the educational intervention targeting adaptation of MTM in the community pharmacy setting. This was found to be significant (46.92% vs. 58.3%; p < 0.001). Responses to the semi-structured interviews were mapped against CFIR and included themes: "knowledge and beliefs about MTM (pre-intervention)," "self-efficacy for MTM implementation (pre-intervention)," "knowledge and beliefs about MTM (post-intervention)," and "self-efficacy for MTM implementation (post-intervention)." Data convergence was found across these methodologies and suggested that targeting adaptability of MTM delivery increases MTM completion rates (quantitative data) and positively changes perceptions of MTM feasibility and self-efficacy (interviews).Conclusion: The use of an educational intervention about adaptation of MTM to influence adaptation of MTM to a chain community pharmacy setting part of an implementation strategy improved MTM completion rates significantly. Future research should investigate combined implementation strategies and their impact on MTM implementation success. [ABSTRACT FROM AUTHOR]

A novel perspective on defining black holes designed to be more broadly applicable outside of asymptotically flat spacetimes, in the context of classical general relativity, is presented, discussed, and characterized. The construction formalizes the heuristic idea that black holes are the "past Cauchy development of the set of singularities". As such, the formulation depends in a critical way on the identification of singularities, which has been treated in the literature through various boundary constructions. While many of the known boundary constructions (e.g.Schmidt's b-boundary or Geroch's g-boundary) could in principal be cited as underlying one's notion of a black hole, well-known topological concerns leads us to take the perspective that Scott and Szekeres' abstract boundary provides the most natural choice. The framework is utilized to put forward a general, non-IVP formulation of the Weak Cosmic Censorship Conjecture. • Intuitively developed a novel, general, and global definition of classical black holes. • Captures global nature of a black hole without any asymptotic requirement. • Demonstrated definitions in several classic black hole spacetimes. • Rigorously affirmed several key intuitive features of the definitions. • Used this to pose a general non-IVP formulation of weak cosmic censorship. [ABSTRACT FROM AUTHOR]

Although frequently examined as a target organ for non-endocrine toxicity, histopathological evaluation of the liver is becoming a routine component of endocrine disruption studies that utilize various fish species as test subjects. However, the interpretation of microscopic liver findings can be challenging, especially when attempting to distinguish adverse changes associated with endocrine disrupting substances from those caused by systemic or direct hepatic toxicity. The purpose of this project was to conduct a critical assessment of the available peer-reviewed and grey literature concerning the histopathologic effects of reproductive endocrine active substances (EAS) and non-endocrine acting substances in the livers of fish models, and to determine if liver histopathology can be used to reliably distinguish endocrine from non-endocrine etiologies. The results of this review suggest that few compound-specific histopathologic liver effects have been identified, among which are estrogen agonist-induced increases in hepatocyte basophilia and proteinaceous intravascular fluid in adult male teleosts, and potentially, decreased hepatocyte basophilia in female fish exposed to substances that possess androgenic, anti-estrogenic, or aromatase inhibitory activity. This review also used published standardized methodology to assess the credibility of the histopathology data in each of the 117 articles that reported liver effects of treatment, and consequently it was determined that in only 37% of those papers were the data considered either highly credible or credible. The outcome of this work highlights the value of histopathologic liver evaluation as an investigative tool for EAS studies, and provides information that may have implications for EAS hazard assessment. [ABSTRACT FROM AUTHOR]

This review critically examines the data on claimed endocrine-mediated adverse effects of chemicals on wildlife populations. It focuses on the effects of current-use chemicals, and compares their apparent scale and severity with those of legacy chemicals which have been withdrawn from sale or use, although they may still be present in the environment. The review concludes that the effects on wildlife of many legacy chemicals with endocrine activity are generally greater than those caused by current-use chemicals, with the exception of ethinylestradiol and other estrogens found in sewage effluents, which are causing widespread effects on fish populations. It is considered that current chemical testing regimes and risk assessment procedures, at least those to which pesticides and biocides are subjected, are in part responsible for this improvement. This is noteworthy as most ecotoxicological testing for regulatory purposes is currently focused on characterizing apical adverse effect endpoints rather than identifying the mechanism(s) responsible for any observed effects. Furthermore, a suite of internationally standardized ecotoxicity tests sensitive for potential endocrine-mediated effects is now in place, or under development, which should ensure further characterization of substances with these properties so that they can be adequately regulated. [ABSTRACT FROM AUTHOR]

Considerable uncertainty surrounds the impacts of anthropogenic climate change on the composition and structure of Amazon forests. Building upon results from two large-scale ecosystem drought experiments in the eastern Brazilian Amazon that observed increases in mortality rates among some tree species but not others, in this study we investigate the physiological traits underpinning these differential demographic responses. Xylem pressure at 50% conductivity (xylem-P50), leaf turgor loss point ( TLP), cellular osmotic potential (π o), and cellular bulk modulus of elasticity (ε), all traits mechanistically linked to drought tolerance, were measured on upper canopy branches and leaves of mature trees from selected species growing at the two drought experiment sites. Each species was placed a priori into one of four plant functional type ( PFT) categories: drought-tolerant versus drought-intolerant based on observed mortality rates, and subdivided into early- versus late-successional based on wood density. We tested the hypotheses that the measured traits would be significantly different between the four PFTs and that they would be spatially conserved across the two experimental sites. Xylem-P50, TLP, and π o, but not ε, occurred at significantly higher water potentials for the drought-intolerant PFT compared to the drought-tolerant PFT; however, there were no significant differences between the early- and late-successional PFTs. These results suggest that these three traits are important for determining drought tolerance, and are largely independent of wood density-a trait commonly associated with successional status. Differences in these physiological traits that occurred between the drought-tolerant and drought-intolerant PFTs were conserved between the two research sites, even though they had different soil types and dry-season lengths. This more detailed understanding of how xylem and leaf hydraulic traits vary between co-occuring drought-tolerant and drought-intolerant tropical tree species promises to facilitate a much-needed improvement in the representation of plant hydraulics within terrestrial ecosystem and biosphere models, which will enhance our ability to make robust predictions of how future changes in climate will affect tropical forests. [ABSTRACT FROM AUTHOR]

The authors reflect on the significant considerations in the establishment of a successful clinical practice. Topics discussed include the search for the unmet needs in clinical facilities, the establishment of the clinical practice, pitching of clinical practice ideas, the communication between parties in faculty positions, and the promotion of these practices.

The understory of the redwood forests of California's coast harbors perennial ferns, including Polystichum munitum and Dryopteris arguta. Unusual for ferns, these species are adapted to the characteristic Mediterranean-type dry season, but the mechanisms of tolerance have not been studied., The water relations of P. munitum and D. arguta were surveyed for over a year, including measures of water potential (Ψ), stomatal conductance ( gs) and frond stipe hydraulic conductivity ( K). A dehydration and re-watering experiment on potted P. munitum plants corroborated the field data., The seasonal Ψ varied from 0 to below −3 MPa in both species, with gs and K generally tracking Ψ; the loss of K rarely exceeded 80%. Quantile regression analysis showed that, at the 0.1 quantile, 50% of K was lost at −2.58 and −3.84 MPa in P. munitum and D. arguta, respectively. The hydraulic recovery of re-watered plants was attributed to capillarity., The seasonal water relations of P. munitum and D. arguta are variable, but consistent with laboratory-based estimates of drought tolerance. Hydraulic and Ψ recovery following rain allows perennial ferns to survive severe drought, but prolonged water deficit, coupled with insect damage, may hamper frond survival. The legacy effects of drought on reproductive capacity and community dynamics are unknown. [ABSTRACT FROM AUTHOR]

The article focuses on the development and implementation of an interdisciplinary pulmonary care clinic at the University of Tennessee (UT) family medicine residency clinic in response to the prevalence of asthma and chronic obstructive pulmonary disorder (COPD) in the U.S. It mentions a brief background on the family medicine residency clinic, the processes for patient referrals and types of return visits to the clinic ranging from asthma care to smoking cessation visits.

In this article the author discusses role of adverse outcome pathway (AOP) framework in chemical safety assessment. Topics discussed include use of biomarkers in environmental monitoring, toxicity testing guidelines proposed by the Organization for Economic Co-operation and Development (OECD) and, need to understand internal dose for molecular initiating events.

The chronic toxicity of chemicals to fish is routinely assessed by using fish early life stage (ELS) test results. Fish full life cycle (FLC) tests are generally required only when toxicity, bioaccumulation, and persistence triggers are met or when there is a suspicion of potential endocrine-disrupting properties. This regulatory approach is based on a relationship between the results of fish ELS and FLC studies first established more than 35 yrs ago. Recently, this relationship has been challenged by some regulatory authorities, and it has been recommended that more substances should undergo FLC testing. In addition, a project proposal has been submitted to the Organisation for Economic Cooperation and Development (OECD) to develop a fish partial life cycle (PLC) test including a reproductive assessment. Both FLC and PLC tests are animal- and resource-intensive and technically challenging and should therefore be undertaken only if there is clear evidence that they are necessary for coming to a regulatory decision. The present study reports on an analysis of a database of paired fish ELS and FLC endpoints for plant protection product active substances from European Union draft assessment reports and the US Environmental Protection Agency Office of Pesticide Programs Pesticide Ecotoxicity Database. Analysis of this database shows a clear relationship between ELS and FLC responses, with similar median sensitivity across substances when no-observed-effect concentrations (NOECs) are compared. There was also no indication that classification of a substance as a mammalian reproductive toxicant leads to more sensitive effects in fish FLC tests than in ELS tests. Indeed, the response of the ELS tests was generally more sensitive than the most sensitive reproduction NOEC from a FLC test. This analysis indicates that current testing strategies and guidelines are fit for purpose and that there is no need for fish full or partial life cycle tests for most plant protection product active substances. Environ Toxicol Chem 2014;33:1874-1878. © 2014 SETAC [ABSTRACT FROM AUTHOR]

Endocrine screening assays not only provide mechanistic information on the potential of a substance to interact with the endocrine system, but also data potentially relevant for risk assessment. However, these screening assays have a number of limitations that should be considered before the direct use of such data for risk assessment purposes. This paper discusses the limitations that should be considered for both human and environmental risk assessment. A proposal is made to provide an objective and transparent process in order to consider which endpoint(s) might be incorporated into a risk assessment, and when more definitive studies may be of value. The proposal is complemented with an easy-to-follow flowchart to aid industry scientists and regulators when evaluating the relevance of these data. Such an approach is necessary to ensure the appropriate use of screening data to further our understanding of the eco/toxicological profile of substances undergoing screening. [ABSTRACT FROM AUTHOR]

We prove new incidence bounds between a plane point set, which is a Cartesian product, and a set of translates H of the hyperbola x y = λ ≠ 0 , over a field of asymptotically large positive characteristic p. They improve recent bounds by Shkredov, which are based on using explicit incidence estimates in the early terminated procedure of repeated applications of the Cauchy-Schwarz inequality, underlying many qualitative results related to growth and expansion in groups. The improvement – both quantitative, plus we are able to deal with a general H , rather than a Cartesian product – is mostly due to a non-trivial "intermediate" bound on the number of k -rich Möbius hyperbolae in positive characteristic. In addition, we make an observation that a certain energy-type quantity in the context of H can be bounded via the L 2 -moment of the Minkowski distance in H and can therefore fetch the corresponding estimates apropos of the Erdős distinct distance problem. [ABSTRACT FROM AUTHOR]

Cavitation has long been recognized as a key constraint on the structure and functional integrity of the xylem. Yet, recent results call into question how well we understand cavitation in plants. Here, we consider embolism formation in angiosperms at two scales. The first focuses on how air-seeding occurs at the level of pit membranes, raising the question of whether capillary failure is an appropriate physical model. The second addresses methodological uncertainties that affect our ability to infer the formation of embolism and its reversal in plant stems. Overall, our goal is to open up fresh perspectives on the structure-function relationships of xylem. [ABSTRACT FROM AUTHOR]

The acute and chronic toxicity of chemicals to fish is routinely assessed using fish acute and early life stage (ELS) test results, usually with freshwater species. Under some regulations with certain substances, however, data on saltwater species may also be required. Evidence from earlier studies suggests that saltwater fish species are generally no more sensitive than freshwater species and that when they are more sensitive to a substance the difference in sensitivity is usually less than a factor of 10. However, most of these studies concentrated on acute lethal toxicity results for a wide range of substances and across a range of taxonomic groups. In the present study, the authors compare freshwater and saltwater acute median lethal concentration (LC50) and chronic ELS no-observed-effect concentration (NOEC) results from standardized regulatory studies specifically for fish species exposed to the same plant protection or biocidal product active substances to determine the value of testing in both freshwater and saltwater fish. The results suggest that, in most cases, use of a freshwater fish 96-h LC50 or longer-term ELS NOEC should be sufficient to protect saltwater species. In a small number of cases (12%), saltwater ELS NOECs were more sensitive by a factor >10, although differences in sensitivity were not consistent for this small number of substances when 96-h LC50 and longer-term ELS NOECs were compared. It is debatable whether such a low probability merits the additional animal use required to run saltwater fish tests, especially when onshore contaminants released to estuaries and coastal environments are likely to be diluted many-fold when compared with concentrations found in freshwaters. Environ Toxicol Chem 2014;33:703-707. © 2013 SETAC [ABSTRACT FROM AUTHOR]

We tested the hypothesis that an age-dependent reduction in leaf hydraulic conductance (K[sub leaf]) influences the timing of leaf senescence via limitation of the stomatal aperture on xylem compound delivery to leaves of tomato (Solanum lycopersicum L.), the tropical trees Anacardium excelsum Kunth,Pittoniotis trichantha Griseb, and the temperate trees Acer saccharum Marsh. and Quercus rubra L. The onset of leaf senescence was preceded by a decline in K[sub leaf] in tomato and the tropical trees, but not in the temperate trees. Age-dependent changes in K[sub leaf] in tomato were driven by a reduction in leaf vein density without a proportional increase in the xylem hydraulic supply. A decline in stomatal conductance accompanied K[sub leaf] reduction with age in tomato but not in tropical and temperate tree species. Experimental manipulations that reduce the flow of xylem-transported compounds into leaves with open stomata induced early leaf senescence in tomato and A. excelsum, but not in P. trichantha, A. saccharum and Q. rubra leaves. We propose that in tomato, a reduction in K[sub leaf] limits the delivery of xylem-transported compounds into the leaves, thus making them vulnerable to senescence. In the tropical evergreen tree A. excelsum, xylem-transported compounds may play a role in signalling the timing of senescence but are not under leaf hydraulic regulation; leaf senescence in the deciduous trees A. trichanta, A. saccharum and Q. rubrais not influenced by leaf vascular transport. [ABSTRACT FROM AUTHOR]

Abstract: To use and implement an assessment scheme for the evaluation of endocrine disrupting properties of chemicals in ecotoxicology, the types of effect need to be agreed. Effects that merit further consideration in this context should fulfil the following three criteria: caused by an endocrine mode of action, be adverse, and be relevant at the population level to reflect the protection goal of ecotoxicological assessments. Thereafter, a comparison of effect values, regardless of the causative mechanisms, should be made, firstly to determine if endocrine toxicity generates the lowest endpoint within a taxon, and secondly if it is the lowest endpoint compared to that of other taxa living in the same compartment. These comparisons inform on two levels of specificity and determine if endocrine-mediated side-effects determine the ecotoxicological profile of a chemical. Various quantitative measures for the assessment of potency are also presented, which could assist in determining how to handle substances in the risk assessment when a regulatory concern is identified. Finally, derogation criteria should be defined for compounds that were designed as endocrine disruptors for non-vertebrates and those for which there is ‘negligible exposure’. This paper discusses and provides proposals on how to apply these concepts for assessment of substances. [Copyright &y& Elsevier]

Highlights: [•] Solvent carriers are discussed in terms of the practical, statistical and regulatory considerations. [•] Analysis using a database of 141 responses (endpoints) from 73 experiments. [•] Conditional strategy to control choice is recommended. [•] Wherever possible a solvent should not be employed or at least the concentration minimized. [Copyright &y& Elsevier]

We investigated the common assumption that severing stems and petioles under water preserves the hydraulic continuity in the xylem conduits opened by the cut when the xylem is under tension. In red maple and white ash, higher percent loss of conductivity ( PLC) in the afternoon occurred when the measurement segment was excised under water at native xylem tensions, but not when xylem tensions were relaxed prior to sample excision. Bench drying vulnerability curves in which measurement samples were excised at native versus relaxed tensions showed a dramatic effect of cutting under tension in red maple, a moderate effect in sugar maple, and no effect in paper birch. We also found that air injection of cut branches (red and sugar maple) at pressures of 0.1 and 1.0 MPa resulted in PLC greater than predicted from vulnerability curves for samples cut 2 min after depressurization, with PLC returning to expected levels for samples cut after 75 min. These results suggest that sampling methods can generate PLC patterns indicative of repair under tension by inducing a degree of embolism that is itself a function of xylem tensions or supersaturation of dissolved gases (air injection) at the moment of sample excision. Implications for assessing vulnerability to cavitation and levels of embolism under field conditions are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Fish in vivo screening methods to detect endocrine active substances, specifically interacting with the hypothalamic–pituitary–gonadal axis, have been developed by both the Organization for Economic Co-operation and Development (OECD) and United States Environmental Protection Agency (US-EPA). In application of these methods, i.e. regulatory testing, this paper provides a proposal on the setting of test concentrations using all available acute and chronic data and also discusses the importance of avoiding the confounding effects of systemic toxicity on endocrine endpoints. This guidance is aimed at reducing the number of false positives and subsequently the number of inappropriate definitive vertebrate studies potentially triggered by effects consequent to systemic, rather than endocrine, toxicity. At the same time it provides a pragmatic approach that maximizes the probability of detecting an effect, if it exists, thus limiting the potential for false negative outcomes. [Copyright &y& Elsevier]

Trunks of large trees play an important role in whole-plant water balance but technical difficulties have limited most hydraulic research to small stems, leaves, and roots. To investigate the dynamics of water-related processes in tree trunks, such as winter embolism refilling, xylem hydraulic vulnerability, and water storage, volumetric water content (VWC) in the main stem was monitored continuously using frequency domain moisture sensors in adult Betula papyrifera trees from early spring through the beginning of winter. An air injection technique was developed to estimate hydraulic vulnerability of the trunk xylem. Trunk VWC increased in early spring and again in autumn, concurrently with root pressure during both seasons. Diurnal fluctuations and a gradual decrease in trunk VWC through the growing season were observed, which, in combination with VWC increase after significant rainfall events and depletion during periods of high water demand, indicate the importance of stem water storage in both short- and long-term water balance. Comparisons between the trunk air injection results and conventional branch hydraulic vulnerability curves showed no evidence of ‘vulnerability segmentation’ between the main stem and small branches in B. papyrifera. Measurements of VWC following air injection, together with evidence from air injection and xylem dye perfusion, indicate that embolized vessels can be refilled by active root pressure but not in the absence of root pressure. The precise, continuous, and non-destructive measurement of wood water content using frequency domain sensors provides an ideal way to probe many hydraulic processes in large tree trunks that are otherwise difficult to investigate. [ABSTRACT FROM AUTHOR]

Tactical wireless and mobile networks are the primary networking infrastructure in the Global Information Grid (GIG) to provide end-to-end connectivity to the warfighters at the tactical edge. The highly dynamic nature of tactical edge networks raise a number of challenging issues related to data transport and service delivery in the tactical environment. To address some of these issues, DoD waveforms have increasingly leveraged layer 2 link information to make smart cross-layer multihop routing decisions. Although there has been some measure of success in providing higher end-to-end data delivery, the lack of standard interfaces between the radio and router have led to interoperability issues in environments with a heterogeneous mix of radio systems. As a result, there has been increased desire to standardize radio-to-router interfaces (R2RIs) as a means to separate radio and router functionality and to allow greater interoperability between systems. In this article, we examine three R2RI protocols currently being vetted through the Internet Engineering Task Force and currently integrated or under consideration in DoD radio systems (RFC 5578, R2CP, and DLEP), and identify their current use and applicability in the tactical edge. Furthermore, we identify some challenges in implementing any R2RI scheme into emerging systems. [ABSTRACT FROM PUBLISHER]

Of those gauge theories of gravity known to be equivalent to general relativity, only the biconformal gauging introduces new structures - the quotient of the conformal group of any pseudo-Euclidean space by its Weyl subgroup always has natural symplectic and metric structures. Using this metric and symplectic form, we show that there exist canonically conjugate, orthogonal, metric submanifolds if and only if the original gauged space is Euclidean or signature 0. In the Euclidean cases, the resultant configuration space must be Lorentzian. Therefore, in this context, time may be viewed as a derived property of general relativity. [ABSTRACT FROM AUTHOR]

Fish toxicity testing has been conducted since the 1860's in order to help define safe levels of chemical contaminants in lakes, rivers and coastal waters. The historical emphasis on acute lethality testing of chemicals has more recently focussed on long term sublethal effects of chemicals on fish and their prey species. Fish toxicity testing is now embedded in much environment legislation on chemical safety while it is recognized that animal use should be Replaced, Reduced and Refined (the 3Rs) where possible. The OECD Fish Toxicity Testing Framework provides a useful structure with which to address the needs of environmental safety assessment whilst implementing the 3Rs. This commentary aims to promote the implementation of the recommendations of the OECD Fish Toxicity Testing Framework. [ABSTRACT FROM AUTHOR]

Background: Pancreatic cancer remains a disease with a poor prognosis. Historically, response rates to chemotherapy alone remain low, and response duration lasts only months, with no clear improvement in survival. This study compiled the data from a pilot phase II trial and a retrospective review of cases with a treatment protocol involving combined use of selective internal radiation therapy (SIRT) using yttrium 90 (90Y) resin microspheres directed to hepatic metastases, selective external radiation treatment (SERT) using TomoTherapy (TomoTherapy Inc., Madison, WI) directed to pancreatic bed disease, and 5-fluorouracil infusional chemotherapy adminstered to patients with metastatic pancreatic cancer. Methods: The study population consisted of patients with pancreatic cancer metastatic to the liver, with or without pancreatic bed disease. Those with liver and pancreatic bed disease were offered the chemotherapy-SIRT-SERT complete protocol, whereas those with liver-only disease were eligible for the chemotherapy-SIRT combination. Patients underwent visceral angiography, technetium 99m macroaggregated albumin scanning, and pancreatic protocol fluorine 18 fluorodeoxyglucose- positron emission-computed tomography (PET-CT) scan. Determinations of the administered activity resulting from 90Y microsphere SIRT were made based on dosimetric calculations using medical internal radiation dosimetry. In the delivery of SERT, the target volume was composed of the pancreatic tumor and any positive lymph nodes and specifically excluded the liver metastasis. Objective response measures included the CA 19.9 level for the evaluation of overall disease status and PETCT- based determinations of standard uptake volume (SUV), functional tumor volume (FTV), total lesion glycolysis (TLG), and anatomic tumor volume. Results: Seven patients had both liver and pancreatic bed disease and received the complete chemotherapy-SIRT-SERT protocol and four patients received chemotherapy-SIRT for liver-only disease. In the chemotherapy-SIRT-treated field, seven of the nine patients demonstrated a decrease in SUV avg and six patients showed a decrease in FTV and TLG. In the chemotherapy- SERT-treated field, six of the seven patients who received TomoTherapy demonstrated a decrease in SUV avg , five patients showed a decrease in FTV, and six patients demonstrated a decrease in TLG. Disease progression was observed in four patients with extrapancreaticohepatic lesions not covered with SIRT or SERT. [ABSTRACT FROM AUTHOR]

In addition to the widely recognized increases in population and jobs, the South has also expanded greatly in the number of major corporations, based on Fortune magazine data. Most of these big corporations are concentrated in the major metropolitan areas of Houston, Dallas-Fort Worth, Atlanta, and Washington. In addition, several second-tiered centers (Charlotte, Memphis, Richmond, Birmingham, and Miami) have also developed a notable corporate presence, as have certain nonmetropolitan areas (in particular, Bentonville, Arkansas, and Wilkesboro, North Carolina, headquarters of Wal-Mart and Lowe's respectively). Corporate headquarters have become more concentrated in the largest metropolitan areas from 1995 to 2003. Some large southern corporations gained in rank between 1995 and 2003, such as Home Depot, while others, declined in rank, especially BellSouth and DuPont. Agglomeration economies, the importance of face-to-face communications, and the clustering of telecommunications infrastructure are related to the growth and aggregation of Fortune corporate headquarters in the large and fast-growth metropolitan areas in the U.S. South. [ABSTRACT FROM AUTHOR]

We derive both Lagrangian and Hamiltonian mechanics as gauge theories of Newtonian mechanics. Systematic development of the distinct symmetries of dynamics and measurement suggest that gauge theory may be motivated as a reconciliation of dynamics with measurement. Applying this principle to Newton's law with the simplest measurement theory leads to Lagrangian mechanics, while use of conformal measurement theory leads to Hamiltonian mechanics.PACS Nos.: 45.20.Jj, 11.25.Hf, 45.10.–b [ABSTRACT FROM AUTHOR]

Biconformal spaces contain the essential elements of quantum mechanics, making the independent imposition of quantization unnecessary. Based on three postulates characterizing motion and measurement in biconformal geometry, we derive standard quantum mechanics, and show how the need for probability amplitudes arises from the use of a standard of measurement. Additionally, we show that a postulate for unique, classical motion yields Hamiltonian dynamics with no measurable size changes, while a postulate for probabilistic evolution leads to physical dilatations manifested as measurable phase changes. Our results lead to the Feynman path integral formulation, from which follows the Schrödinger equation. We discuss the Heisenberg uncertainty relation and fundamental canonical commutation relations. [ABSTRACT FROM AUTHOR]

The article discusses whether the new standards for pharmacy technician education as of July 2019 are effective in reforming pharmacy practice. Other topics include the partnership between the American Society of Health-System Pharmacists (ASHP) and the Accreditation Council for Pharmacy Education (ACPE) to issue accreditation standards for pharmacy technician education and training programs, as well as the potential benefits like improved patient safety.

Vitellogenin, the fish egg yolk precursor protein, is the most common biochemical endpoint in general use for the detection of (anti) estrogen active substances in fish and other oviparous species. This review aims to cover the major methods (both protein and nucleic acid) for vitellogenin determination. Comparisons are drawn between vitellogenin and other endpoint effect levels. This review highlights strengths and weaknesses of the various techniques, concentrating on practical considerations and problems in evaluating the data they generate. [ABSTRACT FROM AUTHOR]

The hypothesis that greater safety from cavitation by air-seeding through inter-vessel pits comes at the cost of less porous pit membranes with greater flow resistance was tested . Sixteen vessel-bearing species were compared: 11 from the Rosaceae, four from other angiosperm families, and one fern. Unexpectedly, there was no relationship between pit resistance (and hence the prevailing membrane porosity) and cavitation pressure. There was, however, an inverse relationship between pit area per vessel and vulnerability to cavitation ( r2 = 0.75). This suggests that cavitation is caused by the rare largest membrane pore per vessel, the average size of which increases with total pit area per vessel. If safety from cavitation constrains pit membrane surface area, it also limits vessel surface area and the minimum vessel resistivity. This trade-off was consistent with an approximately three-fold increase in vessel resistivity with cavitation pressure dropping from −0.8 to −6.6 MPa. The trade-off was compensated for by a reduction in the percentage of vessel wall pitted: from 10–16% in vulnerable species to 2–4% in resistant species. Across species, end-wall pitting accounted for 53 ± 3% of the total xylem resistivity. This corresponded to vessels achieving on average 94 ± 2% of their maximum possible conductivity if vessel surface area is constrained. [ABSTRACT FROM AUTHOR]

A survey of topics of recent interest in Hamiltonian and Lagrangian dynamical systems, including accessible discussions of regularization of the central-force problem; inequivalent Lagrangians and Hamiltonians; constants of central-force motion; a general discussion of higher order Lagrangians and Hamiltonians, with examples from Bohmian quantum mechanics, the Korteweg–de Vries equation, and the logistic equation; gauge theories of Newtonian mechanics; and classical spin, Grassmann numbers, and pseudomechanics. PACS No.: 45.25.Jj [ABSTRACT FROM AUTHOR]

Presents the author's account of his experiences as a foreigner working as an electronics engineer in a hospital in Ethiopia. Reasons for working in the country; Problems with faulty equipment; Job challenges; Observations on the level of engineering skills in the country.

Biconformal supergravity models provide a new gauging of the superconformal group relevant to the Maldacena conjecture. Using the group quotient method to biconformally gauge SU(2,2&z.sfnc;N), we generate a 16-dim superspace. We write the most general even- and odd-parity actions linear in the curvatures, the bosonic sector of which is known to descend to general relativity on a 4-dim manifold. [Copyright &y& Elsevier]

: BackgroundSpermicides containing nonoxynol-9 (N-9) may increase HIV transmission. In women, intravaginal N-9 is found in the uterus shortly after its insertion. Exposure of the female upper reproductive tract to N-9 may alter epithelial integrity, thereby increasing HIV transmission risk. Our goal was to characterize the histological effects of N-9 on uterine epithelium in an animal model.: MethodsFemale mice were exposed to intravaginal or intrauterine Advantage-S™ (N-9), Replens™, K-Y® jelly or water. After various exposure times, mice were sacrificed and stained uterine tissue sections were analyzed by a pathologist blinded to treatment.: ResultsIntravaginal and intrauterine N-9 administration resulted in disruption of uterine epithelium compared to Replens, K-Y jelly or water. N-9 caused rapid (within 10 min), focal, uterine epithelial sloughing and complete epithelial loss within 24 h. Epithelial regeneration began 48 h after exposure N-9 and was completely restored within 72 h; the new epithelial layer, however, was composed of cuboidal cells instead of normally present columnar cells. In addition, hemorrhage and necrosis were present are all time points examined.: ConclusionsOur results demonstrate for the first time that N-9 has a deleterious effect on uterine epithelium. Although these results were observed in a mouse model, similar disruption of the upper reproductive tract epithelium in women by N-9 may facilitate HIV infection and serve as an unrecognized portal of human HIV transmission. [Copyright &y& Elsevier]

Our groups have had a long-term interest in utilizing bacterial systems in the characterization of bioactivation and detoxication reactions catalyzed by cytochrome P450 (P450) and glutathione transferase (GST) enzymes. Bacterial systems remain the first choice for initial screens with new chemicals and have advantages, including high-throughput capability. Most human P450s of interest in toxicology have been readily expressed in Escherichia coli with only minor sequence modification. These enzymes can be readily purified and used in assays of activation of chemicals. Bicistronic systems have been developed in order to provide the auxiliary NADPH-P450 reductase. Alternative systems involve these enzymes expressed together within bacteria. In one approach, a lac selection system is used with E. coli and has been applied to the characterization of inhibitors of P450s 1A2 and 1B1, as well as in basic studies involving random mutagenesis. Another approach utilizes induction of the SOS (umu) response in Salmonella typhimurium, and systems have now been developed with human P450s 1A1, 1A2, 1B1, 2C9, 2D6, 2E1, and 3A4, which have been used to report responses from heterocyclic amines. S. typhimurium his reporter systems have also been used with GSTs, first to demonstrate the role of rat GST 5-5 in the activation of dihalomethanes. These systems have been used to compare these GSTs with regard to activation of dihaloalkanes and potential toxicity. [Copyright &y& Elsevier]

There is generally a lack of saltwater ecotoxicity data for risk assessment purposes, leaving an unknown margin of uncertainty in saltwater assessments that utilize surrogate freshwater data. Consequently, a need for sound scientific advice on the suitability of using freshwater data to extrapolate to saltwater effects exists. Here we use species sensitivity distributions to determine if freshwater datasets are adequately protective of saltwater species assemblages for 21 chemical substances. For ammonia and the metal compounds among these data, freshwater data were generally protective because freshwater organisms tended to be more sensitive. In contrast, for pesticide and narcotic compounds, saltwater species tended to be more sensitive and a suitable uncertainty factor would need to be applied to surrogate freshwater data. Biological and physicochemical factors contribute to such differences in freshwater and saltwater species sensitivities, but the species compositions of datasets used are also important. [ABSTRACT FROM AUTHOR]

In 1930, a time when human geography was not considered to be among the emerging analytic social sciences and when urban geography barely existed as an identifiable subfield, C. Warren Thornthwaite, later a gargantuan figure in American climatology, was awarded a doctorate under Carl O. Sauer at the University of California, Berkeley. In his dissertation, 'Louisville, Kentucky: a study in urban geography', Thornthwaite analysed land-use zonation, commercial strip development, daytime-night-time populations, community formation, elevation and land values, functional regions and cultural areas, spatial competition and optimal location, buying power and residential distribution. Thornthwaite's urban geography was centered unmistakably in the spatial tradition, and his innovative research - based on aerial photographs, intensive field observations, city directories and detailed mapping - treated concepts that were to become central to urban geography as it developed in the late 1950s and the 1960s. Urban geography, however, evolved independently of Thornthwaite's contributions. Thornthwaite directed no graduate students, and his unpublished dissertation was not cited until a perfunctory reference in 1954. A second citation, not appearing until almost 30 years later, described it as 'a major synthesis'. Thornthwaite's dissertation was not only an anomaly in the career of its author but also an anachronism in the history of urban geography. [ABSTRACT FROM AUTHOR]

Despite an increase of 200,000 jobs in business and professional services in the Atlanta metropolitan area between 1982 and 1997, the central city saw employment as a percentage of these services drop by approximately 20 percent. Most growth occurred in the northern suburbs, resulting in a dispersed distribution of business and professional services in Atlanta. To understand the spatial distribution and suburbanization of business and professional services in Atlanta, regression analysis was carried out for 1982 and 1992. Flexible female workers, corporate headquarters, well –educated professionals, and highway access turned out to be important location determinants, with the latter two being increasingly responsible for the suburbanization of business and professional services. [ABSTRACT FROM AUTHOR]

There are a number of methods of estimating dermal contamination. "Potential exposure" methods, such as patch and whole-body oversuit sampling, intercept the contaminant before it reaches the skin. "Actual exposure" measurements recover the contaminant from the skin by wiping, stripping, or rinsing, or, in the case of fluorescent tracer dye monitoring, assess it in-situ on the skin. These different methods can give rise to very different results. Comparison of methods is difficult, because they usually interfere within-subject. This presentation is a comparison of two compatible 'actual dermal contamination' measurement techniques. They are: (1) fluorescence monitoring of a tracer dye in-situ on the skin, using ultraviolet light and a video camera linked to an image processor; (2) rinsing of the skin to recover a metal tracer salt for later assay in solution. Several painting and spraying application tasks were carried out by a panel of volunteers who wore T-shirts, shorts, and open sandals. The exercises simulated domestic or non-occupational tasks. Results showed excellent agreement, with discrepancies identified and explained. The good agreement of the two completely different, independent tracer methods for measuring skin contamination contributes to their mutual validation. [ABSTRACT FROM AUTHOR]

Biconformal gravity, based on gauging of the conformal group to 2 n dimensions, reproduces n -dim scale-covariant general relativity on the co-tangent bundle in any dimension. We generalize this result to include Yang-Mills matter sources formulated as S U (N) gauge theories with a twisted action on the full 2 n -dimensional biconformal space. We show that the coupling of the sources to gravity does not stop the reduction of effective dimension 2 n → n of the gravity theory, and instead forces the Yang-Mills source to reduce to ordinary n -dimensional Yang-Mills theory on the gravitating cotangent bundle, with the usual Yang-Mills energy tensor as gravitational source. The results apply as well to gravity with sources on Kähler manifolds and in double field theories. [ABSTRACT FROM AUTHOR]