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Plants acquire multiple resources from the environment and may need to adjust and/or balance their respective resource-use efficiencies to maximize grow and survival, in a locally adaptive manner. In this study, tissue and whole-plant carbon isotopic composition (δ13C) and C/N ratios provided long-term measures of use efficiencies for water (WUE) and nitrogen (NUE), and a nitrogen isotopic composition (δ15N) based mass balance model was used to estimate traits related to N uptake and assimilation in heart-leaved willow (Salix eriocephala Michx.). In an initial common garden experiment consisting of 34 populations, we found population level variation in δ13C, C/N and δ15N, indicating different patterns in WUE, NUE and N uptake and assimilation. Although there was no relationship between foliar δ13C and C/N ratios among populations, there was a significant negative correlation between these measures across all individuals, implying a genetic and/or plastic trade-off between WUE and NUE not associated with local adaptation. To eliminate any environmental effect, we grew a subset of 21 genotypes hydroponically with nitrate as the sole N-source, and detected significant variation in δ13C, δ15N and C/N ratios. Variation in δ15N was mainly due to genotypic differences in the nitrate efflux/influx ratio (E/I) at the root. Both experiments suggested clinal variation in δ15N (and thus N uptake efficiency) with latitude of origin, which may relate to water availability and could contribute to global patterns in ecosystem δ15N. There was a tendency for genotypes with higher WUE to come from more water replete sites with shorter and cooler growing seasons. We found that δ13C, C/N, and E/I were not inter-correlated, suggesting that selection of growth, WUE, NUE and N uptake efficiency can occur without trade-off.

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Aim:This study aims to identify the role that spiritual climate has in reducing burnout and intentions to leave amongst clinical nurses.Background: Both shortages and the high turnover of nurses are challenging problems worldwide. Enhancing the spiritual climate amongst nurses can enhance teamwork, organisational commitment and job satisfaction and can play a role in reducing burnout and turnover intention. Methods:A total of 207 clinical nurses working at a tertiary university hospital were included in this cross-sectional, single-site study. Independent-samples t test and ANOVA, Pearson correlation analysis and hierarchical regression analysis were used to explore the relationships amongst related factors. Results:Most clinical departments showed a moderate spiritual climate (60.24 ± 0.82) with high job burnout (33.62 ± 0.28) and turnover intention (2.37 ± 0.57). A good spiritual climate was correlated with high job satisfaction (r = 0.412, p < 0.01), low burnout and turnover intention (r = −0.423, p < 0.01 and r = −0.292, p < 0.01, respectively). Spiritual climate could also indirectly influence nurses' job burnout and turnover intention (R 2 = 10.31%). Conclusions: Different departments have different spiritual climates. The findings from this study indicate that spiritual climate may impact nursing burnout and turnover. Implications for nursing management: Using a spiritual climate scale provides health care decision-makers with clear information about staff spirituality wellbeing. Interventions to improve spiritual climate can benefit teamwork in clinical departments. K E Y W O R D S burnout, job satisfaction, nurses, spiritual climate, spirituality, turnover intention

The study demonstrated significantly enhanced filling of the bone-implant gap and bone ingrowth in association with the porous tantalum implants coated with calcium phosphate and alendronate.

The inhibitive effects of chitosan on gray mold caused by Botrytis cinerea on cherry tomato fruit were evaluated. Decay incidence was tested on tomato stored at 22 °C. Hydrogen peroxide accumulation, malondialdehyde (MDA) production, peroxidase (POD) activity, and several related gene expressions (including MPK3, MPK6, PR1a1, and PR5) were determined. Results showed that 0.2% of chitosan solution significantly inhibited the tomato gray mold 3 days after inoculation. Hydrogen peroxide accumulated in the fruit epidermal peel along with chitosan treatment, while MDA production was not increased. POD activity was remarkably enhanced by the application of chitosan. The relative expressions of MPK3, MPK6, and PR1a1 were significantly induced in 10 min after chitosan treatment, while PR5 was induced in 20 min. These findings suggested that the effects of chitosan on inhibiting gray mold in cherry tomato fruit were probably associated with the mitogen-activated protein kinase (MAPK) signaling pathway.

After root uptake, nitrate is effluxed back to the medium, assimilated locally, or translocated to shoots. Rooted black cottonwood (Populus trichocarpa) scions were supplied with a NO 3 −-based (0.5 mM) nutrient medium of known isotopic composition (δ 15 N), and xylem sap was collected by pressure bombing. To establish a sampling protocol, sap was collected from lower and upper stem sections at 0.1-0.2 MPa above the balancing pressure, and after increasing the pressure by a further 0.5 MPa. Xylem sap from upper stem sections was partially diluted at higher pressure. Further analysis was restricted to sap obtained from intact shoots at low pressure. Total-, NO 3 −-N and, by difference, organic-N concentrations ranged from 6.1-11.0, 1.2-2.4, and 4.6-9.4 mM, while discrimination relative to the nutrient medium was −6.3 to 0.5‰, −23.3 to −11.5‰ and − 1.3 to 4.9‰, respectively. There was diurnal variation in δ 15 N of total-and organic-N, but not NO 3 −. The difference in δ 15 N between xylem NO 3 − and organic-N suggests that discrimination by nitrate reductase is near 25.1 ± 1.6‰. When this value was used in an isotope mass balance model, the predicted xylem sap NO 3 −-N to total-N ratio closely matched direct measurement. K E Y W O R D S black cottonwood, isotope discrimination, nitrate reductase, nitrogen isotopes, nitrogen uptake and assimilation 1 | INTRODUCTION Nitrogen is the primary limiting nutrient for most plants in terrestrial ecosystems (Glass et al., 2002). The various forms and pools of nitrogen in the environment, and in the plant, typically have differences in the relative abundance of 15 N (δ 15 N). These differences in isotopic composition are widely used in the study of nitrogen cycling in ecosystems and individual organisms (Dawson, Mambelli, Plamboeck, Templer, & Tu, 2002). However, interpretation of variation in δ 15 N at natural abundance levels can be problematic. For example, the δ 15 N of an individual plant or one of its parts is not only determined by the external nitrogen source, of which there is often more than one, but also by internal physiological factors, such as different nitrogen uptake mechanisms, different pathways of assimilation and transport, and the possibility of differential recycling of nitrogen within the plant, all of which may discriminate against 15 N (Robinson, 2001). A better understanding of isotope discrimination that may or may not be associated with these various factors is needed before variation in δ 15 N can be routinely used in ecological and/or physiological research. Nitrogen sources in soils include nitrate, ammonium and organic nitrogen. These are distributed unevenly in time and space, in varying proportions that depend on profile position, local vegetation, climate and many other edaphic factors (Amundson et al., 2003). For example, boreal forests generally have less inorganic nitrogen in soils than temperate forests because of colder temperatures and slower rates of mineralization (Näsholm et al., 1998). Also, because they are often acidic, boreal fo...

Porous calcium polyphosphate (CPP) is being investigated for fabrication of novel biodegradable bone substitutes. In this study, porous CPP implants formed by conventional CPP powder packing and using a two-step sinter/anneal process was used to form 20 and 30 vol % porous samples displaying relatively high strength. These were implanted in rabbit femoral condyle sites to study their ability for secure fixation in prepared sites through bone ingrowth. Porous implants of 20 and 30 vol % porosity and displaying compressive strengths ~80 and 35 MPa, respectively, were used. Bone ingrowth sufficient to allow secure implant fixation was observed by 6 weeks (~19% bone ingrowth per available pore space for the 30 vol % and 13% for the 20 vol % porous implants). The results of the in vivo study suggest the potential usefulness of porous CPP as biodegradable bone substitutes/augments in high load-bearing skeletal regions.