Increasing leaf hydraulic conductance with transpiration rate minimizes the water potential drawdown from stem to leaf.

Leaf hydraulic conductance (k leaf) is a central element in the regulation of leaf water balance but the properties of k leaf remain uncertain. Here, the evidence for the following two models for k leaf in well-hydrated plants is evaluated: (i) k leaf is constant or (ii) k leaf increases as transpiration rate (E) increases. The difference between stem and leaf water potential (ΔΨstem-leaf), stomatal conductance (g s), k leaf, and E over a diurnal cycle for three angiosperm and gymnosperm tree species growing in a common garden, and for Helianthus annuus plants grown under sub-ambient, ambient, and elevated atmospheric CO₂ concentration were evaluated. Results show that for well-watered plants k leaf is positively dependent on E. Here, this property is termed the dynamic conductance, k leaf(E), which incorporates the inherent k leaf at zero E, which is distinguished as the static conductance, k leaf(0). Growth under different CO₂ concentrations maintained the same relationship between k leaf and E, resulting in similar k leaf(0), while operating along different regions of the curve owing to the influence of CO₂ on g s. The positive relationship between k leaf and E minimized variation in ΔΨstem-leaf. This enables leaves to minimize variation in Ψleaf and maximize g s and CO₂ assimilation rate over the diurnal course of evaporative demand

Resource use and study habits in a first-year mathematics service unit

We analysed students’ actual and intended use of a variety of study resources in a first year mathematics service course. We combined online tracking with self-report via survey and interviews. Our major finding was that students desire and intend to use a variety of resources but in actuality focus on traditional modes of engagement. We also found evidence that these students adopted different study habits and a different learning approach in their service maths units as compared to their discipline units

Conflicting evidence for the role of JNK as a target in breast cancer cell proliferation: comparisons between pharmacological inhibition and selective shRNA knockdown approaches

As a target, the JNK pathway has been implicated in roles including cell death, proliferation, and inflammation in variety of contexts which span cardiovascular disease, neurodegenerative pathologies, and cancer. JNK1 and JNK2 have recently been demonstrated to function independently, highlighting a new parameter in the study of the JNK pathway. In order for JNK1 and JNK2-specific roles to be defined, better tools need to be employed. Previous studies have relied upon the broad spectrum JNK inhibitor, SP600125, to characterize the role of JNK signaling in a number of cell lines, including the breast cancer cell line MCF-7. In line with previous literature, our study has demonstrated that SP600125 treatment inhibited c-Jun and JNK phosphorylation and MCF-7 proliferation. However, in addition to targeting JNK1, JNK2, and JNK3, SP600125 has been previously demonstrated to suppress the activity of a number of other serine/threonine kinases, making SP600125 an inadequate tool for JNK isoform-specific roles to be determined. In this study, lentiviral shRNA was employed to selectively knockdown JNK1, JNK2, and JNK1/2 in MCF-7 cells. Using this approach, JNK phosphorylation was fully inhibited following stable knockdown of respective JNK isoforms. Interestingly, despite suppression of JNK phosphorylation, MCF-7 cell proliferation, cell cycle progression, or cell death remained unaffected. These findings raise the question of whether JNK phosphorylation really is pivotal in MCF-7 cell growth and death or if suppression of these events is a result of one of the many off-targets cited for SP600125

SITE Joint SIG Symposia: A Collaboration Between the K-12 Online Learning SIG and Distance Learning SIG: How Higher Education and K-12 Online Learning Research Can Impact Each Other

Facilitated by Rick Ferdig of Kent State University and editor of JTATE, this Symposia brings together the work of the K-12 Online Learning SIG and the Distance Learning SIG communities and focuses on presentations from scholars in the field whose work has implications for both higher education and K-12 online learning. This Symposia will have nine panelists who will each present their work and then talk specifically about how their work can inform both K-12 and HE. Included in the list of Higher Education-focused panelists are Trisha Litz of Regis University, Maggie Niess of Oregon State University, Antoinette Davis of Eastern Kentucky University, and David Marcovitz of Loyola University Maryland. Included in the list of K-12-focused panelists are Leanna Archambault of Arizona State University, Kerry Rice of Boise State University, Michael Barbour of Touro University, Amy Garrett Dikkers of the University of North Carolina at Charlotte, and Aimee Whiteside of the University of Tampa

SITE Joint SIG Symposia: A Collaboration Between the K-12 Online Learning SIG and Distance Learning SIG: How Higher Education and K-12 Online Learning Research Can Impact Each Other

Facilitated by Rick Ferdig of Kent State University and editor of JTATE, this Symposia brings together the work of the K-12 Online Learning SIG and the Distance Learning SIG communities and focuses on presentations from scholars in the field whose work has implications for both higher education and K-12 online learning. This Symposia will have nine panelists who will each present their work and then talk specifically about how their work can inform both K-12 and HE. Included in the list of Higher Education-focused panelists are Trisha Litz of Regis University, Maggie Niess of Oregon State University, Antoinette Davis of Eastern Kentucky University, and David Marcovitz of Loyola University Maryland. Included in the list of K-12-focused panelists are Leanna Archambault of Arizona State University, Kerry Rice of Boise State University, Michael Barbour of Touro University, Amy Garrett Dikkers of the University of North Carolina at Charlotte, and Aimee Whiteside of the University of Tampa

An international survey and modified Delphi process revealed editors' perceptions, training needs, and ratings of competency-related statements for the development of core competencies for scientific editors of biomedical journals

Background: Scientific editors (i.e., those who make decisions on the content and policies of a journal) have a central role in the editorial process at biomedical journals. However, very little is known about the training needs of these editors or what competencies are required to perform effectively in this role. Methods: We conducted a survey of perceptions and training needs among scientific editors from major editorial organizations around the world, followed by a modified Delphi process in which we invited the same scientific editors to rate the importance of competency-related statements obtained from a previous scoping review. Results: A total of 148 participants completed the survey of perceptions and training needs. At least 80% of participants agreed on six of the 38 skill and expertise-related statements presented to them as being important or very important to their role as scientific editors. At least 80% agreed on three of the 38 statements as necessary skills they perceived themselves as possessing (well or very well). The top five items on participants’ list of top training needs were training in statistics, research methods, publication ethics, recruiting and dealing with peer reviewers, and indexing of journals. The three rounds of the Delphi were completed by 83, 83, and 73 participants, respectively, which ultimately produced a list of 23 “highly rated” competency-related statements and another 86 “included” items. Conclusion: Both the survey and the modified Delphi process will be critical for understanding knowledge and training gaps among scientific editors when designing curriculum around core competencies in the future

A scoping review of competencies for scientific editors of biomedical journals

Background Biomedical journals are the main route for disseminating the results of health-related research. Despite this, their editors operate largely without formal training or certification. To our knowledge, no body of literature systematically identifying core competencies for scientific editors of biomedical journals exists. Therefore, we aimed to conduct a scoping review to determine what is known on the competency requirements for scientific editors of biomedical journals. Methods We searched the MEDLINE®, Cochrane Library, Embase®, CINAHL, PsycINFO, and ERIC databases (from inception to November 2014) and conducted a grey literature search for research and non-research articles with competency-related statements (i.e. competencies, knowledge, skills, behaviors, and tasks) pertaining to the role of scientific editors of peer-reviewed health-related journals. We also conducted an environmental scan, searched the results of a previous environmental scan, and searched the websites of existing networks, major biomedical journal publishers, and organizations that offer resources for editors. Results A total of 225 full-text publications were included, 25 of which were research articles. We extracted a total of 1,566 statements possibly related to core competencies for scientific editors of biomedical journals from these publications. We then collated overlapping or duplicate statements which produced a list of 203 unique statements. Finally, we grouped these statements into seven emergent themes: (1) dealing with authors, (2) dealing with peer reviewers, (3) journal publishing, (4) journal promotion, (5) editing, (6) ethics and integrity, and (7) qualities and characteristics of editors. Discussion To our knowledge, this scoping review is the first attempt to systematically identify possible competencies of editors. Limitations are that (1) we may not have captured all aspects of a biomedical editor’s work in our searches, (2) removing redundant and overlapping items may have led to the elimination of some nuances between items, (3) restricting to certain databases, and only French and English publications, may have excluded relevant publications, and (4) some statements may not necessarily be competencies. Conclusion This scoping review is the first step of a program to develop a minimum set of core competencies for scientific editors of biomedical journals which will be followed by a training needs assessment, a Delphi exercise, and a consensus meeting

Chlorhexidine hexametaphosphate as a wound care material coating: antimicrobial efficacy, toxicity and effect on healing.

AIM: In this study, chlorhexidine hexametaphosphate (CHX-HMP) is investigated as a persistent antimicrobial coating for wound care materials. MATERIALS & METHODS: CHX-HMP was used as a wound care material coating and compared with chlorhexidine digluconate materials with respect to antimicrobial efficacy, toxicity and wound closure. RESULTS: Antimicrobial efficacy at day 1, 3 and 7 was observed with experimental and commercial materials. CHX-HMP coated materials had less toxic effect on human placental cells than commercial chlorhexidine dressings. CHX-HMP in pluronic gel did not delay healing but reduced wound colonization by E. faecalis. CONCLUSION: CHX-HMP could become a useful component of wound care materials with sustained antimicrobial efficacy, lower toxicity than chlorhexidine digluconate materials, and reduction in wound colonization without affecting closure

Mesophyll diffusion conductance to CO 2: An unappreciated central player in photosynthesis

Mesophyll diffusion conductance to CO 2 is a key photosynthetic trait that has been studied intensively in the past years. The intention of the present review is to update knowledge of g m, and highlight the important unknown and controversial aspects that require future work. The photosynthetic limitation imposed by mesophyll conductance is large, and under certain conditions can be the most significant photosynthetic limitation. New evidence shows that anatomical traits, such as cell wall thickness and chloroplast distribution are amongst the stronger determinants of mesophyll conductance, although rapid variations in response to environmental changes might be regulated by other factors such as aquaporin conductance.Gaps in knowledge that should be research priorities for the near future include: how different is mesophyll conductance among phylogenetically distant groups and how has it evolved? Can mesophyll conductance be uncoupled from regulation of the water path? What are the main drivers of mesophyll conductance? The need for mechanistic and phenomenological models of mesophyll conductance and its incorporation in process-based photosynthesis models is also highlighted.The study was financially supported by the Estonian Ministry of Science and Education (grant SF1090065s07), the Spanish Ministry of Science and Innovation through projects BFU2008-01072 (MEFORE), AGL2009-11310/AGR, BFU2011-23294 (MECOME) and CGL2009-13079-C02-01 (PALEOISOTREE), and the European Commission through European Regional Fund (the Estonian Center of Excellence in Environmental Adaptation), and the Marie Curie project MC-ERG-246725 (FP7). J.P.F. is supported by the Ramón y Cajal program (RYC-2008-02050). A.G. had a Swiss National Science Fellowship (PA00P3_126259). M.M.B. and C.R.W are supported by Future Fellowships from the Australian Research Council (FT0992063 and FT100100024). C.D. was supported by a grant from the French government and by the cooperation project Tranzfor (Transferring Research between EU and Australia–New Zealand on Forestry and Climate Change, PIRSES-GA-2008-230793) funded by the European Union

Can hydraulic design explain patterns of leaf water isotopic enrichment in C3 plants?

H2 18 O enrichment develops when leaves transpire, but an accurate generalized mechanistic model has proven elusive. We hypothesized that leaf hydraulic architecture may affect the degree to which gradients in H2 18 O develop within leaves, influencing bulk leaf stable oxygen isotope enrichment (ΔL ) and the degree to which the Péclet effect is relevant in leaves. Leaf hydraulic design predicted the relevance of a Péclet effect to ΔL in 19 of the 21 species tested. Leaves with well-developed hydraulic connections between the vascular tissue and the epidermal cells through bundle sheath extensions and clear distinctions between palisade and spongy mesophyll layers (while the mesophyll is hydraulically disconnected) may have velocities of the transpiration stream such that gradients in H2 18 O develop and are expressed in the mesophyll. In contrast, in leaves where the vascular tissue is hydraulically disconnected from the epidermal layers, or where all mesophyll cells are well connected to the transpiration stream, velocities within the liquid transport pathways may be low enough that gradients in H2 18 O are very small. Prior knowledge of leaf hydraulic design allows informed selection of the appropriate ΔL modelling framework.K.E.L. was supported by an Australian Postgraduate Award and A.S. was supported by an Australian Postgraduate Award and International Postgraduate Research Support. Australian Research Council, Grant/Award Number: DP17010427