Responses of an alpine plant to warming temperatures: from plasticity to molecular pathways

Rapid changes to climatic parameters, including temperature, pose substantial threat to species persistence and biodiversity. Climate warming has been more rapid in alpine systems than lowland environments, however studies of responses to high temperature stress in alpine plants are lacking; particularly transcriptomic and genomic studies are nearly absent. Being sessile, plants must respond and adapt to changing environmental conditions in situ. In this regard, phenotypic plasticity is described as a rapid and adaptive mechanism to respond to climate change, however many fundamental questions about plasticity are yet unsolved, including its genetic and molecular underpinnings. Answering said fundamental questions, such as whether plasticity is adaptive, will help us better understand which species can be resilient to climate change. The overall objectives of this thesis were to (1) characterize the plastic phenotypic response of the alpine herb Wahlenbergia ceracea to warming and heatwaves using a whole-of-life cycle approach to address fundamental questions about plasticity; and (2) to examine changes in gene expression in response to warmer temperatures as an intermediate component of the molecular basis of plasticity. To determine whether the alpine plant W. ceracea will be able to tolerate projected, future warmer temperatures and heatwaves I examine plasticity in a range of relevant traits in lineages (the group of half-siblings obtained with targeted crosses) from low and high elevation (Chapter 2). When grown under warmer temperatures, W. ceracea plants showed signs of acclimation by means of higher thermal tolerance (Tcrit) but this did not confer resilience to heatwaves. High- and low-elevation lines exhibited limited genetic variation in plasticity, suggesting canalisation of the plastic response. To assess the effect of warming on the seed size vs number trade-off and on germination responses, I conduct germination assays under relatively cool and warm temperatures using seeds produced by parental individuals grown under cool and warm temperatures (Chapter 3). The reductions in seed size and number in parents grown under warm temperatures resulted in the breakdown of the seed size vs number trade-off, but this did not affect germination, despite correlations of these seed traits with germination traits. Warming increased germination, particularly of larger seeds, but overall resulted in more than fourfold reduction in parental fitness. To investigate the molecular pathways regulated in response to temperature and involved in physiological acclimation, I examine the differential gene expression of tolerant and sensitive lines grown under cool and warm temperatures using RNA-seq (Chapter 4). Under warm growth temperatures, plants upregulated post-translational processes and downregulated processes related to photosynthesis. Interestingly, tolerant lines showed stronger downregulation of genes involved in photosynthesis light harvesting, electron transport chain and photosystem II repair/assembly. In Chapter 5 I bring together the previous chapters by linking gene expression to mean trait values and plastic changes therein. I found that co-expressed genes involved in photosynthetic processes were correlated with the physiological parameter Fv/Fm. Genes involved in cell wall and cytoskeleton organisation were correlated with the number of reproductive stems. My thesis represents one of the few works in plant ecology addressing intraspecific variation in plasticity and its relationship with fitness and transcriptomic regulation in a native plant. Overall, the results showed that significant plasticity in many traits did not confer resilience to warmer conditions, as fitness was substantially reduced. The transcriptomic analyses highlighted candidate genes potentially involved in photosynthetic acclimation as measured by chlorophyll fluorescence, opening avenues for future research

Prevalence of methicillin-resistant staphylococci isolated from different biological samples at Policlinico Umberto I of Rome: correlation with vancomycin susceptibility

The methicillin-resistance is increasing all over the world in the last decade. It is more frequent among coagulase-negative staphylococci (MRCoNS); infact the 52% of S. epidermidis strains results to be resistant to methicillin.The methicillin-resistant strains also show a reduced sensitivity towards the first-line agents such as glycopeptides and other antibiotics commonly used in therapy such as trimethoprim-sulphamethoxazole, imipenem, gentamycin, fosfomycin and chlarytromicin. Unlike MRSA (Methicillin-resistant S. aureus), MRCoNS resistance to glycopeptides generally concerns teicoplanin. Although vancomycin resistance is rare in Staphylococcus isolates, the detected shift towards higher values of MICs might affect patient's clinical outcome

Tolerance of warmer temperatures does not confer resilience to heatwaves in an Alpine herb

Climate change is generating both sustained trends in average temperatures and higher frequency and intensity of extreme events. This poses a serious threat to biodiversity, especially in vulnerable environments, like alpine systems. Phenotypic plasticity is considered to be an adaptive mechanism to cope with climate change in situ, yet studies of the plastic responses of alpine plants to high temperature stress are scarce. Future weather extremes will occur against a background of warmer temperatures, but we do not know whether acclimation to warmer average temperatures confers tolerance to extreme heatwaves. Nor do we know whether populations on an elevational gradient differ in their tolerance or plasticity in response to warming and heatwave events. We investigated the responses of a suite of functional traits of an endemic Australian alpine herb, Wahlenbergia ceracea, to combinations of predicted future (warmer) temperatures and (relative) heatwaves. We also tested whether responses differed between high- vs. low-elevation populations. When grown under warmer temperatures, W. ceracea plants showed signs of acclimation by means of higher thermal tolerance (Tcrit, T50, and Tmax). They also invested more in flower production, despite showing a concurrent reduction in photosynthetic efficiency (Fv/Fm) and suppression of seed production. Heatwaves reduced both photosynthetic efficiency and longevity. However, we found no evidence that acclimation to warmer temperatures conferred tolerance of the photosynthetic machinery to heatwaves. Instead, when exposed to heatwaves following warmer growth temperatures, plants had lower photosynthetic efficiency and underwent a severe reduction in seed production. High- and low-elevation populations and families exhibited limited genetic variation in trait means and plasticity in response to temperature. We conclude that W. ceracea shows some capacity to acclimate to warming conditions but there is no evidence that tolerance of warmer temperatures confers any resilience to heatwaves.This research was supported by the Australian Research Council (DP170101681), an International Ph.D. Scholarship to RN and an ARC Future Fellowship FT110100453 to LK. Research grants funded all research related costs (such as renting growth chambers or buying equipment), while the scholarship paid a stipend to RN

Effects of warming temperatures on germination responses and trade-offs between seed traits in an alpine plant

1. Climate warming may affect multiple aspects of plant life history, including important factors such as germination responses and the key trade-off between offspring size and number. As a case study to address these concepts, we used an alpine plant (waxy bluebell, Wahlenbergia ceracea; Campanulaceae) that shows plasticity to warming in seed traits and in which seed dormancy status regulates germination. We chose an alpine species because alpine environments are ecosystems particularly under threat by climate change. 2. We conducted germination assays under cool and warm temperatures using seeds produced by individuals that were grown under historical (cooler) and future (warmer) temperature scenarios. We assessed the presence of a seed size vs number trade-off, and then examined the effects of seed number and size on germination percentage, the fractions of dormant and viable seeds, and germination velocity. Further, we examined whether warming during parental growth and during germination affected these relationships. 3. We found evidence for a seed size vs number trade-off only under historical parental temperatures. Indeed, under future growth temperatures, parental plants produced fewer and smaller seeds and there was no evidence of a trade-off. However, the reductions in both seed traits under warming did not affect germination, despite correlations of seed size and number with germination traits. Warming increased germination, particularly of larger seeds, but overall it resulted in more than fourfold reductions in parental fitness. 4. Synthesis. Our study shows the importance of growth conditions when evaluating the seed size vs number trade-off. Stressful conditions, such as warmer temperatures, can restrain the ability of plants to reach optimal investment in reproduction, masking the trade-off. By analysing responses across the whole life cycle, we show here an overall detrimental effect of warming, highlighting the potential risk of climate change for W. ceracea, and, potentially, for alpine plant communities more widely.Files can be opened using Excel and analysed using R.Funding provided by: Australian Research CouncilCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100000923Award Number: DP170101681Experiments were conducted using the plant species Wahlnebrgia ceracea (waxy bluebells). Two datasets were used in this manuscript. 1) Seed size vs number trade-off: Parental individuals from a total of 30 lines ('Line') were grown in growth chambers for 191 days under temperature conditions of a historical/cooler (1960–1970) or a projected future/warmer (2090–2100) climate ('Parental_Temperature'). The parental individuals were randomly assigned to one of three blocks, which corresponded to positions inside the chambers, and each block was equivalent in all chambers ('Block'). Day and night temperatures during the experiment were changed every 15 days to mimic seasonality, with the maximum day temperatures during the peak of summer being 24°C and 29°C for the historical and future parental temperatures, respectively. After 100 days since the imposition of the temperature treatments (during the peak of the summer), half of the plants were moved for 5 days to new chambers, where the temperature was 5°C above the respective treatments, i.e., 29°C and 34°C ('Heatwave'). After this time, the parental individuals were moved back to their respective historical or future temperature treatments. We collected the seeds throughout the 191 days of parental growth, and we stored them in desiccators for at least 11 weeks. After this time, we calculated seed size ('Seed_Size') as the average mass of three lots of 50 seeds divided by 50. We calculated seed number ('Seed_Number') as the ratio between the cumulative mass of the seeds produced by each parental individual and seed size. The 30 lines of the parental individuals were obtained by crossing plants that originated from seeds that were collected at the same elevation, either high or low elevation ('Elevation') in sites within Kosciuszko National Park, NSW, Australia. Therefore, 14 lines originated from high elevations and 14 lines from low elevations. 2) Germination responses - seed traits correlations: The seeds were harvested from the parental individuals grown under historical/cooler or projected future/warmer temperatures ('Parental_Temperature') (see above) from a subset of 14 lines ('Line'). These seeds were used in germination assays in the glasshouse under cool (25°C) or warm temperatures (30°C) ('Germination_Temperature'). We measured seed size ('Seed_Size') as the average mass of three lots of 50 seeds; then these seeds were sowed in agar dishes (25 seeds per dish, 2 dishes per temperature treatment from each parental individual). Seed number ('Seed_Number') was the same as above. Dishes were left under temperature treatments for 4 weeks to allow germination of the non-dormant fraction of the seeds ('Not_Dormant_Seeds') and germination was checked once per week. Then, all the dishes were moved to a cold room at 4–5°C in the dark for 4 weeks to allow cold stratification. After this time, dishes were moved back to the glasshouse under the same temperature treatments as before to allow germination of the dormant seeds. We considered seeds to be dormant ('Dormant_seeds') if they germinated during or after cold stratification or if they did not germinate at all but were still determined to be viable at the end of the experiment. We considered seed to be viable ('Viable_Seeds') if they germinated ('Germinated_Seeds') as well as the seeds that contained an endosperm but still did not germinate ('Not_Germinated_Seeds'), while we considered empty seeds as non-viable ('Not_Viable_Seeds'). Germinated and not germinated seeds (as above) were used to calculate the germination percentage. We calculated germination velocity ('Germination_Velocity') as the reciprocal of the mean germination time (germination velocity (germination (%) week-1) GV = (G1 + G2 +…+ Gn) / (G1 x T1 + G2 x T2 +…+ Gn x Tn), where Gn is the number of new germinating seeds at each sampling point, and Tn is the time between each sampling point (= one week). The files provided present the datasets in their first sheet and keys with the definitions of each term in the second sheet

Psychometric Characteristics of the Self-Care of Chronic Illness Inventory in Older Adults Living in a Middle-Income Country

: Chronic illness requires numerous treatments and self-care is essential in the care process. Evaluation of self-care behaviors facilitates the identification of patients' needs and optimizes education and care processes. This study aimed to test the psychometric characteristics (validity, reliability, and measurement error) of the Albanian version of the Self-Care of Chronic Illness Inventory (SC-CII). Patients with multiple chronic conditions and caregivers were recruited in outpatient clinics in Albania. The patients completed the SC-CII, which includes three scales: self-care maintenance, self-care monitoring, and self-care management. Factorial validity was tested for each scale, with confirmatory factor analysis. Reliability was evaluated with the composite coefficient, Cronbach's alpha, and the global reliability index for multidimensional scales. The construct validity was tested using hypothesis testing and known differences between groups. The measurement error was tested to assess responsiveness to changes. The self-care maintenance and self-care monitoring scales showed a unidimensional factorial structure, while the self-care management scale showed a bidimensional structure. Reliability estimates were adequate for all reliability coefficients. Construct validity was supported. The measurement error was adequate. The Albanian version of the SC-CII shows good psychometric properties in the Albanian sample

Factors Influencing Generation Z Bachelor of Nursing Students’ Decision to Choose Nursing as a Career: A Pilot Study

bachelor in nursingundergraduate nursing educationchoice behaviou

Psychometric Properties of the Italian Version of the Leader Member Exchange Scale (LMX-7): A Validation Study

For decades, scholars have studied leader–member exchange (LMX) relationships to understand and explain the effects of leadership on follower attitudes and performance outcomes within work settings. One available instrument to measure these aspects is the LMX-7 scale. This measurement has been widely used in empirical studies, but its psychometric properties have been poorly explored. The aim of this study was to test the psychometric characteristics (content, structural and construct validity, and reliability) of the Italian version of the LMX-7 scale and to support its cultural adaptation. We used a cross-sectional multi-center design. The forward–backward translation process was used to develop the Italian version of the scale. The scale was administered through an online survey to 837 nurses and nurse managers working in different settings. The factorial structure was tested using both exploratory and confirmatory factor analyses (EFA and CFA), and reliability was evaluated using Cronbach’s alpha. For the construct validity, we used hypothesis testing and differentiation by known groups. The Italian version of the LMX-7 scale presented one dimension. All the psychometric tests performed confirmed its validity and suggested its usefulness for future research

Appraisal and Evaluation of the Learning Environment Instruments of the Student Nurse: A Systematic Review Using COSMIN Methodology

Background: Nursing education consists of theory and practice, and student nurses’ perception of the learning environment, both educational and clinical, is one of the elements that determines the success or failure of their university study path. This study aimed to identify the currently available tools for measuring the clinical and educational learning environments of student nurses and to evaluate their measurement properties in order to provide solid evidence for researchers, educators, and clinical tutors to use in the selection of tools. Methods: We conducted a systematic review to evaluate the psychometric properties of self-reported learning environment tools in accordance with the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) Guidelines of 2018. The research was conducted on the following databases: PubMed, CINAHL, APA PsycInfo, and ERIC. Results: In the literature, 14 instruments were found that evaluate both the traditional and simulated clinical learning environments and the educational learning environments of student nurses. These tools can be ideally divided into first-generation tools developed from different learning theories and second-generation tools developed by mixing, reviewing, and integrating different already-validated tools. Conclusion: Not all the relevant psychometric properties of the instruments were evaluated, and the methodological approaches used were often doubtful or inadequate, thus threatening the instruments’ external validity. Further research is needed to complete the validation processes undertaken for both new and already developed instruments, using higher-quality methods and evaluating all psychometric propertie

Assessment of the Psychometric Characteristics of the Italian Version of the Nurse Manager Actions Scale

Nurse managers play a vital role in healthcare organizations, wielding the ability to substantially enhance work environments, foster nurses’ autonomy, and bolster retention within workplaces. In this context, this study focuses on the Nurse Manager Actions scale, aiming to evaluate its items’ scalability as well as the scale’s validity and reliability among nurses and nurse managers operating within the Italian healthcare context. The study protocol was not registered. To ensure linguistic and cultural alignment, an iterative and collaborative translation process was undertaken. Subsequently, a multi-center cross-sectional design was adopted. Using a web-survey approach, data were collected among 683 nurses and 188 nurse managers between August 2022 and January 2023. The Nurse Manager Actions scale was found to be a valid and reliable instrument in Italian after a Mokken Scale Analysis. For nurses (HT = 0.630, Molenaar–Sijtsma rho = 0.890), the scale included 6 items, while 11 items were confirmed for nurse managers (HT = 0.620, Molenaar–Sijtsma rho = 0.830). Nurse Manager Actions scale scores were correlated with increased satisfaction and decreased intention to leave for both nurses and nurse managers. The employed validation process enhanced the scale validity for use in Italy and provided a model for other researchers to follow when assessing similar measures in different populations. Measuring and empowering nurse manager actions in work contexts is essential to improve the general well-being and retention of nurses, especially in the current nursing shortage

Self-Perceived Clinical Competence of Nurses in Different Working Experiences: A Cross-Sectional Study

Background: Competence is an essential concept for measuring nurses’ performance in terms of effectiveness and quality. To this end, our analysis highlighted the process of acquiring competencies, their self-evaluation into clinical practice, and how their proficiency levels change throughout the nursing career. In detail, this research explored nurses’ perceived level of competence and the factors that influence it in different contexts. Methods: A cross-sectional survey using a structured questionnaire to assess the nursing participants’ perception of their competencies in different clinical settings was accomplished. Results: A descriptive and bivariate analysis was performed on 431 nurses. Most respondents assessed their level of competence to be higher than their roles required. The Kruskal–Wallis test confirmed that nursing experience was a relevant factor influencing nursing competencies. Conclusions: We suggest improving the competence of practicing nurses, using experience as a measurable effect of their development