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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]

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.

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]

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]

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.

The article discusses the role of videoconferencing in the implementation of the Phase II Match in the National Resident Matching Program in the U.S. It identifies the responsibilities of residency program directors (RPDs) and preceptors in the program. Some of the benefits of videoconferencing to the program are identified, including reduced costs and the streamlined interview process.

Declines in leaf hydraulic conductance (Kleaf) with increasing water stress have been attributed to cavitation of the leaf xylem. However, in the leaves of conifers, the reversible collapse of transfusion tracheids may provide an alternative explanation. Using Taxus baccata, a conifer species without resin, we developed a modified rehydration technique that allows the separation of declines in Kleaf into two components: one reversible and one irreversible upon relaxation of water potential to -1 MPa. We surveyed leaves at a range of water potentials for evidence of cavitation using cryo-scanning electron microscopy and quantified dehydration-induced structural changes in transfusion tracheids by cryo-fluorescence microscopy. Irreversible declines in Kleaf did not occur until leaf water potentials were more negative than -3 MPa. Declines in Kleaf between -2 and -3 MPa were reversible and accompanied by the collapse of transfusion tracheids, as evidenced by cryo-fluorescence microscopy. Based on cryo-scanning electron microscopy, cavitation of either transfusion or xylem tracheids did not contribute to declines in Kleaf in the reversible range. Moreover, the deformation of transfusion tracheids was quickly reversible, thus acting as a circuit breaker regulating the flux of water through the leaf vasculature. As transfusion tissue is present in all gymnosperms, the reversible collapse of transfusion tracheids may be a general mechanism in this group for the protection of leaf xylem from excessive loads generated in the living leaf tissue. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this review is to (1) provide information concerning the opioid crisis including origins, trends, and some important related laws/policies; and (2) summarize the current involvement and impact of pharmacists in helping to address the crisis, as well as examine practices in other healthcare disciplines from which pharmacists might derive guidance and strategies. Summary Contributors to the opioid crisis included campaigns to treat pain as a fifth vital sign and to use opioids in treatment of non-cancer-related pain, as well as aggressive marketing of opioid analgesics by pharmaceutical companies. To address the crisis, numerous strategies have been implemented at the policy/legislative, health-system, and patient levels, such as prescription drug monitoring programs (PDMPs), increased regulation of pain clinics, and expanded use of naloxone. Pharmacists have a critical role to play in interventions to address opioid misuse and reduce harm resulting from misuse. Such interventions include patient screening and risk stratification, patient and community education and outreach concerning appropriate pain management, medication reviews/medication therapy management, education on safe storage and disposal, distribution of naloxone/opioid rescue kits and training on their proper use, and referral of patients to addiction treatment, among other strategies. Conclusion Pharmacists have multiple, complex roles in addressing the opioid crisis. Outcomes of several studies provide substantial evidence that pharmacists can make an impact through appropriate pain management, use of PDMPs, opioid overdose prevention training, and medication reviews and counseling, among other interventions. [ABSTRACT FROM AUTHOR]