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1.
Sci Total Environ ; 916: 169896, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38185160

RESUMO

Widespread shrubification across the Arctic has been generally attributed to increasing air temperatures, but responses vary across species and sites. Wood structures related to the plant hydraulic architecture may respond to local environmental conditions and potentially impact shrub growth, but these relationships remain understudied. Using methods of dendroanatomy, we analysed shrub ring width (RW) and xylem anatomical traits of 80 individuals of Salix glauca L. and Betula nana L. at a snow manipulation experiment in Western Greenland. We assessed how their responses differed between treatments (increased versus ambient snow depth) and soil moisture regimes (wet and dry). Despite an increase in snow depth due to snow fences (28-39 %), neither RW nor anatomical traits in either species showed significant responses to this increase. In contrast, irrespective of the snow treatment, the xylem specific hydraulic conductivity (Ks) and earlywood vessel size (LA95) for the study period were larger in S. glauca (p < 0.1, p < 0.01) and B. nana (p < 0.01, p < 0.001) at the wet than the dry site, while both species had larger vessel groups at the dry than the wet site (p < 0.01). RW of B. nana was higher at the wet site (p < 0.01), but no differences were observed for S. glauca. Additionally, B. nana Ks and LA95 showed different trends over the study period, with decreases observed at the dry site (p < 0.001), while for other responses no difference was observed. Our results indicate that, taking into account ontogenetic and allometric trends, hydraulic related xylem traits of both species, along with B. nana growth, were influenced by soil moisture. These findings suggest that soil moisture regime, but not snow cover, may determine xylem responses to future climate change and thus add to the heterogeneity of Arctic shrub dynamics, though more long-term species- and site- specific studies are needed.


Assuntos
Neve , Solo , Humanos , Groenlândia , Regiões Árticas , Xilema/fisiologia
2.
Glob Chang Biol ; 29(20): 5896-5907, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37526296

RESUMO

Current global change is inducing heterogeneous warming trends worldwide, with faster rates at higher latitudes in the Northern Hemisphere. Consequently, tundra vegetation is experiencing an increase in growth rate and uneven but expanding distribution. Yet, the drivers of this heterogeneity in woody species responses are still unclear. Here, applying a retrospective approach and focusing on long-term responses, we aim to get insight into growth trends and climate sensitivity of long-lived woody species belonging to different functional types with contrasting growth forms and leaf habits (shrub vs. tree and deciduous vs. evergreen). A total of 530 samples from 7 species (common juniper, dwarf birch, woolly willow, Norway spruce, lodgepole pine, rowan, and downy birch) were collected in 10 sites across Iceland. We modelled growth trends and contrasted yearly ring-width measurements, filtering in high- and low-frequency components, with precipitation, land- and sea-surface temperature records (1967-2018). Shrubs and trees showed divergent growth trends, with shrubs closely tracking the recent warming, whereas trees, especially broadleaved, showed strong fluctuations but no long-term growth trends. Secondary growth, particularly the high-frequency component, was positively correlated with summer temperatures for most of the species. On the contrary, growth responses to sea surface temperature, especially in the low frequency, were highly diverging between growth forms, with a strong positive association for shrubs and a negative for trees. Within comparable vegetation assemblage, long-lived woody species could show contrasting responses to similar climatic conditions. Given the predominant role of oceanic masses in shaping climate patterns in the Arctic and Low Arctic, further investigations are needed to deepen the knowledge on the complex interplay between coastal tundra ecosystems and land-sea surface temperature dynamics.


Assuntos
Ecossistema , Madeira , Estudos Retrospectivos , Regiões Árticas , Tundra , Árvores , Folhas de Planta , Mudança Climática
3.
J Exp Bot ; 74(17): 5072-5087, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37352139

RESUMO

The size-related xylem adjustments required to maintain a constant leaf-specific sapwood conductance (KLEAF) with increasing height (H) are still under discussion. Alternative hypotheses are that: (i) the conduit hydraulic diameter (Dh) at any position in the stem and/or (ii) the number of sapwood rings at stem base (NSWr) increase with H. In addition, (iii) reduced stem elongation (ΔH) increases the tip-to-base conductance through inner xylem rings, thus possibly the NSWr contributing to KLEAF. A detailed stem analysis showed that Dh increased with the distance from the ring apex (DCA) in all rings of a Picea abies and a Fagus sylvatica tree. Net of DCA effect, Dh did not increase with H. Using sapwood traits from a global dataset, NSWr increased with H, decreased with ΔH, and the mean sapwood ring width (SWrw) increased with ΔH. A numerical model based on anatomical patterns predicted the effects of H and ΔH on the conductance of inner xylem rings. Our results suggest that the sapwood/heartwood transition depends on both H and ΔH, and is set when the carbon allocation to maintenance respiration of living cells in inner sapwood rings produces a lower gain in total conductance than investing the same carbon in new vascular conduits.


Assuntos
Árvores , Xilema , Folhas de Planta , Água
4.
Transl Med UniSa ; 25(2): 38-49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38343418

RESUMO

Cases of dementia have increased significantly in recent years. The family represents the main cornerstone of assistance to the elderly suffering from dementia, in particular the caregiver. Family members who take on the role of caregiver are subjected to physical, psychological, emotional, social and financial stress, which can be conceptualised with the term "burden". The aim of this study was to investigate which tools are best suited to measure the type of burden based on the type of dementia for each caregiver. A literature search was undertaken in MEDLINE, CINHAL and The Cochrane Database in September 2022, including articles from the last 20 years and using a combination of keywords and defined inclusion criteria. This literature review has been performed according to the PRISMA statement. From a total of 116 articles regarding the use of burden rating scales for caregivers, 18 scales were selected. The review provides a useful overview of burden assessment scales, classified into three categories, one-dimensional, multidimensional, or distinct concept with a subjective and objective component, in order to adopt appropriate strategies to assess caregiver burden and improve the quality of their health, both in the community and in hospitals. Indeed, the domestic context is the most studied as there is a greater risk of developing the burden of the caregiver: for this reason, some scales include the assessment of both the caregiver and the patient receiving treatment.

5.
Sci Total Environ ; 851(Pt 2): 158008, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988628

RESUMO

Rapid climate change has been driving changes in Arctic vegetation in recent decades, with increased shrub dominance in many tundra ecosystems. Dendroecological observations of tundra shrubs can provide insight into current and past growth and recruitment patterns, both key components for understanding and predicting ongoing and future Arctic shrub dynamics. However, generalizing these dynamics is challenging as they are highly scale-dependent and vary among sites, species, and individuals. Here, we provide a perspective on how some of these challenges can be overcome. Based on a targeted literature search of dendrochronological studies from 2005 to 2022, we highlight five research gaps that currently limit dendro-based studies from revealing cross-scale ecological insight into shrub dynamics across the Arctic biome. We further discuss the related research priorities, suggesting that future studies could consider: 1) increasing focus on intra- and interspecific variation, 2) including demographic responses other than radial growth, 3) incorporating drivers, in addition to warming, at different spatial and temporal scales, 4) implementing systematic and unbiased sampling approaches, and 5) investigating the cellular mechanisms behind the observed responses. Focusing on these aspects in dendroecological studies could improve the value of the field for addressing cross-scale and plant community-framed ecological questions. We outline how this could be facilitated through the integration of community-based dendroecology and dendroanatomy with remote sensing approaches. Integrating new technologies and a more multidisciplinary approach in dendroecological research could provide key opportunities to close important knowledge gaps in our understanding of scale-dependencies, as well as intra- and inter-specific variation, in vegetation community dynamics across the Arctic tundra.


Assuntos
Ecossistema , Tundra , Humanos , Regiões Árticas , Mudança Climática
6.
Front Plant Sci ; 13: 855003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755705

RESUMO

High-elevation ecosystems are one of the most sensitive to climate change. The analysis of growth and xylem structure of trees from marginal populations, especially the ones growing at the treeline, could provide early-warning signs to better understand species-specific responses to future climate conditions. In this study, we combined classical dendrochronology with wood density and anatomical measurements to investigate the climate sensitivity of Pinus cembra L., a typical European high-elevation tree species distributed in isolated patches in the Carpathians. Samples were collected from the Retezat Mountains, South-Western Romania. We analyzed ring width (TRW), maximum density (MXD), xylem anatomical traits [cell number per ring (CNo), cell density (CD), conduit area (CA), and cell wall thickness (CWT)] time series, split into ring sectors and assessed the relationships with monthly and daily climate records over the last century (1901-2015). The analysis showed a strong dependency of TRW on CNo and MXD on CWT. Summer temperature positively correlated with MXD and CWT [monthly correlation (r) were 0.65 and 0.48 respectively] from the early to late wood but not TRW (r = 0.22). CA positively correlated with water availability (r = 0.37) and negatively correlated with temperature (r = -0.39). This study improves our general understanding of the climate-growth relationships of a European high-elevation tree species and the results could be considered for forecasting population dynamics on projected changes in climate.

7.
Front Plant Sci ; 13: 822901, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35481143

RESUMO

With the recent climate warming, tundra ecotones are facing a progressive acceleration of spring snowpack melting and extension of the growing season, with evident consequences to vegetation. Along with summer temperature, winter precipitation has been recently recognised as a crucial factor for tundra shrub growth and physiology. However, gaps of knowledge still exist on long-living plant responses to different snowpack duration, especially on how intra-specific and year-to-year variability together with multiple functional trait adjustments could influence the long-term responses. To fill this gap, we conducted a 3 years snow manipulation experiment above the Alpine treeline on the typical tundra species Juniperus communis, the conifer with the widest distributional range in the north emisphere. We tested shoot elongation, leaf area, stomatal density, leaf dry weight and leaf non-structural carbohydrate content of plants subjected to anticipated, natural and postponed snowpack duration. Anticipated snowpack melting enhanced new shoot elongation and increased stomatal density. However, plants under prolonged snow cover seemed to compensate for the shorter growing period, likely increasing carbon allocation to growth. In fact, these latter showed larger needles and low starch content at the beginning of the growing season. Variability between treatments slightly decreased over time, suggesting a progressive acclimation of juniper to new conditions. In the context of future warming scenarios, our results support the hypothesis of shrub biomass increase within the tundra biome. Yet, the picture is still far from being complete and further research should focus on transient and fading effects of changing conditions in the long term.

8.
Sci Rep ; 12(1): 3077, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35197470

RESUMO

The combined effects of climate change and nutrient availability on Arctic vegetation growth are poorly understood. Archaeological sites in the Arctic could represent unique nutrient hotspots for studying the long-term effect of nutrient enrichment. In this study, we analysed a time-series of ring widths of Salix glauca L. collected at nine archaeological sites and in their natural surroundings along a climate gradient in the Nuuk fjord region, Southwest Greenland, stretching from the edge of the Greenlandic Ice Sheet in the east to the open sea in the west. We assessed the temperature-growth relationship for the last four decades distinguishing between soils with past anthropogenic nutrient enrichment (PANE) and without (controls). Along the East-West gradient, the inner fjord sites showed a stronger temperature signal compared to the outermost ones. Individuals growing in PANE soils had wider ring widths than individuals growing in the control soils and a stronger climate-growth relation, especially in the inner fjord sites. Thereby, the individuals growing on the archaeological sites seem to have benefited more from the climate warming in recent decades. Our results suggest that higher nutrient availability due to past human activities plays a role in Arctic vegetation growth and should be considered when assessing both the future impact of plants on archaeological sites and the general greening in landscapes with contrasting nutrient availability.

9.
Nurs Rep ; 11(2): 430-443, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34968219

RESUMO

BACKGROUND: Falls are recognized globally as a major public health problem. Although the elderly are the most affected population, it should be noted that the pediatric population is also very susceptible to the risk of falling. The fall risk approach is the assessment tool. There are different types of tools used in both clinical and territorial settings. MATERIAL AND METHODS: In the month of January 2021, a literature search was undertaken of MEDLINE, CINHAL and The Cochrane Database, adopting as limits: last 10 years, abstract available, and English and Italian language. The search terms used were "Accidental Falls" AND "Risk Assessment" and "Fall Risk Assessment Tool" or "Fall Risk Assessment Tools". RESULTS: From the 115 selected articles, 38 different fall risk assessment tools were identified, divided into two groups: the first with the main tools present in the literature, and the second represented by tools of some specific areas, of lesser use and with less supporting literature. Most of these articles are prospective cohort or cross-sectional studies. All articles focus on presenting, creating or validating fall risk assessment tools. CONCLUSION: Due to the multidimensional nature of falling risk, there is no "ideal" tool that can be used in any context or that performs a perfect risk assessment. For this reason, a simultaneous application of multiple tools is recommended, and a direct and in-depth analysis by the healthcare professional is essential.

10.
Acta Biomed ; 92(4): e2021203, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34487083

RESUMO

BACKGROUND: Sternal wound infection is a severe complication of cardiac surgery in the pediatric population (0-18 years old) that can lead to increased morbidity, mortality, and prolonged hospitalization. Health professionals have the ability to perform some interventions during the pre, intra and post-surgery to correctly manage sternal wounds, with the goal of preventing infections. OBJECTIVES: To identify and discuss current best practice in the prevention, incidence, and treatment of infections of the cardiac surgery site in the pediatric population. METHODS: Between February 20th 2021 and February 28th 2021 we consulted the PubMed database adopting full text, 20 years, Humans, English, Child aged 0 to 18 years as criteria. Twenty articles out of sixty-six were considered relevant to this study. These were divided into four themes. RESULTS: All studies highlight the lack of standard guidelines for managing pediatric patients undergoing cardiac surgery. Some centers developed protocols for managing antibiotic prophylaxis supported by measurable interventions; others implemented infection surveillance systems involving families taking care of patients after hospital discharge. DISCUSSIONS: the identification of healthcare-associated infections in the pediatric population after cardiac surgery is useful in all peri-operative phases. The limited and restricted literature connected to single centers, with relatively small sample sizes, the use of a single database. CONCLUSION: There is a lack of standard guidelines. The prevention of site infection ought to the goal of reducing surgical site infections. Building a network between the multidisciplinary staff and the pediatric patient's family improves the infection surveillance system, reducing the incidence of infections.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Infecção Hospitalar , Adolescente , Antibioticoprofilaxia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Controle de Infecções , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle
11.
Healthcare (Basel) ; 9(7)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34356247

RESUMO

(1) Background: a review of the literature found a lack of standardized pediatric guidelines regarding wound management after cardiac surgery. (2) Objective: the aim of the study is to investigate the cardiac surgical wound management in Italian pediatric cardiac intensive care units. (3) Methods: we sent an online questionnaire to the 13 Italian pediatric cardiac intensive care units. (4) Results: ten pediatric cardiac intensive care units (77%) have a protocol for the management of the cardiac surgical wound. The staff members that mainly have the responsibility for the wound management after cardiac surgery are registered nurses and physicians together both in the pediatric cardiac intensive care units (69%), and when a patient is transferred to another ward (62%). Thirty-eight percent of the pediatric cardiac intensive care units have a protocol used to monitor wound infection, and the staff mostly uses a written shift report (54%) to monitor the infection. (5) Discussion: this is the first survey to investigate the management of the wound after cardiac surgery in Italian pediatric cardiac intensive care units. The small sample size and the fact that the centers involved are only Italian cardiac intensive care units are the limits of this study. (6) Conclusions: in the Italian pediatric cardiac intensive care units it emerged that there is a diversity in the treatments adopted and a lack of specific protocols in the management of the pediatric cardiac surgical wound.

12.
Clin Pract ; 11(3): 472-483, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34449571

RESUMO

BACKGROUND: The process to obtain valid informed consent in healthcare reflects many aspects. Healthcare professionals that take care of the patient must provide him all the necessary information and verify his understanding, considering individual characteristics. Nurses are one of the main participants in this process. OBJECTIVE: This study assesses nurses' perceptions of their role in the informed consent process. MATERIAL AND METHODS: An observational study involving 300 nurses operating in 13 wards of the Padua Hospital, through the submitting of a questionnaire in the period November-December 2018. RESULTS: The final sample is made up of 206 nurses-27 males (13.11%) and 179 females (86.89%). Work experience, on average 15 years, is significant in determining the answers to questions about opinions and experiences. Age is significant in determining how often nurses provide information to the patient's family members about the actions to be taken after discharge. The ward was decisive in the responses related to information provided to patients on the nursing care level and the actions to be taken after discharge, and the definition of the nurse's duties. CONCLUSIONS: The data collected show the need for interventions to reduce the causes of difficult that the nurse has in informing patients.

13.
Sci Total Environ ; 764: 144607, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33387770

RESUMO

Insect defoliations are a major natural disturbance in high-latitude ecosystems and are expected to increase in frequency and severity due to current climatic change. Defoliations cause severe reductions in biomass and carbon investments that affect the functioning and productivity of tundra ecosystems. Here we combined dendro-anatomical analysis with chemical imaging to investigate the direct and lagged effects of insect outbreaks on carbon investment. We analysed the content of lignin vs. holocellulose, i.e. unspecified carbohydrates in xylem samples of Salix glauca L. collected at Iffiartarfik, Nuuk fjord, Greenland, featuring two outbreak events of the moth Eurois occulta L. Cross sections of the growth rings corresponding to both outbreaks ±3 years were analysed using confocal Raman imaging to identify possible chemical signatures related to insect defoliation on fibres, vessels, and ray parenchyma cells and to get insight into species-specific defence responses. Outbreak years with narrower rings and thinner fibre cell walls are accompanied by a change in the content of cell-wall polymers but not their underlying chemistry. Indeed, during the outbreaks the ratio between lignin and carbohydrates significantly increased in fibre but not vessel cell walls due to an increase in lignin content coupled with a reduced content of carbohydrates. Parenchyma cell walls and cell corners did not show any significant changes in the cell-wall biopolymer content. The selective adjustment of the cell-wall composition of fibres but not vessels under stressful conditions could be related to the plants priority to maintain an efficient hydraulic system rather than mechanical support. However, the higher lignin content of fibre cell walls formed during the outbreak events could increase mechanical stiffness to the thin walls by optimizing the available resources. Chemical analysis of xylem traits with Raman imaging is a promising approach to highlight hidden effects of defoliation otherwise overlooked with classical dendroecological methods.


Assuntos
Mariposas , Salix , Animais , Parede Celular , Surtos de Doenças , Ecossistema , Groenlândia , Lignina , Xilema
14.
Nurs Crit Care ; 26(6): 510-516, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33283418

RESUMO

BACKGROUND: Children who develop Acute Kidney Injury may start renal replacement therapy (RRT) in Paediatric or Neonatal Intensive Care Units (hereafter PICU or NICU); RRT can be delivered either by paediatric dialysis nurses or by critical care nurses. In both case, nurses devoted to this task must have a high level of competence in providing care to children receiving haemodialytic treatment in a specific technological environment. AIM: The objective of this research was to investigate which models have been adopted to organize nursing care in RRT management in different Italian PICU and NICU, and to explore the training of ICU nurses on the management of RRT. METHODS: A multi-centre survey was conducted through an online questionnaire directed to the Italian PICU and NICU nurse coordinators. RESULTS: A total of 15 Intensive Care Units (12 PICU and 3 NICU) in 12 hospitals were involved. The mean nurse/patient ratio in these units is 1:3. In 72.7% of critical care units, dialysis treatment is delivered by critical care nurses belonging to the unit itself, while in 27.3% of units paediatric dialysis nurses are in charge of dialysis treatment in collaboration with critical care nurses. In 25% of surveyed units there is some structured form of collaboration between Paediatric Dialysis nurses and critical care nurses. However, 75% of units did not respond to this specific question. The different units adopt various forms of RRT training for nursing staff. CONCLUSION: The scenario resulting from this analysis showed how in our sample of Italian hospitals there is no standard practice for RRT nursing management. In addition, although various forms of training for nursing staff exist, a proper educational programme and/or a standardized specific training about RRT management for nursing staff is not in place in the surveyed hospitals. RELEVANCE TO CLINICAL PRACTICE: The lack of standardized protocols or guidelines for RRT delivery to critically ill children can compromise their safety. The structuring of these protocols and the production of best clinical practice guidelines would allow standardization of the nursing management of the RRT and of the corresponding training. This may help to provide the proper care and to guarantee the patients' safety.


Assuntos
Enfermagem de Cuidados Críticos , Criança , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Enfermagem Pediátrica , Diálise Renal , Terapia de Substituição Renal
15.
Acta Biomed ; 92(S2): e2021502, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-35037631

RESUMO

BACKGROUND: diabetes mellitus is a chronic disease of the endocrine system, characterized by an increase in the concentration of glucose in the blood. For patients with diabetes, it is possible to cover the need for insulin through the use of an insulin pump, a subcutaneous implantable device, which aims to simulate the action of the Langherans islets. Therapy with an insulin pump allows patients who use it to have a greater flexibility in the long-term management of diabetes. OBJECTIVE: to investigate in the literature the perceptions and experiences of patients subjected to the use of the insulin pump. METHODS: this review was carried out using the international databases Pubmed, CINAHL and COCHRANE. The mesh terms "Insulin infusion system, attitude to health, experiences, emotions, perceptions, activities of daily living" were used combined with the Boolean operator AND. Age limits  and language were set and literature was investigated from 2008 to 2018, respecting specific inclusion and exclusion criteria. RESULTS: 260 articles from the Pubmed database were analyzed, 26 articles from Cinhal, no articles by COCHRANE; of these 188 excluded based on the reading of the abstract and because they were duplicate articles, 7 because they did not meet the inclusion criteria. 15 articles were included in the review. DISCUSSION: four main themes emerged regarding the personal experience of patients with insulin pumps: perceptions deriving from the use of the insulin pump, behaviour deriving from therapy, obstacles to adequate glycemic control and discrepancy between education received and reality. CONCLUSIONS: different moods and behaviors have been reported in people who use the insulin pump: one above all the fear of hypoglycemia. There are different expectations from patients and nurses. In addition to adequate training with respect to direct patient care, training is also required for nursing staff in emotional support and in technological development.


Assuntos
Diabetes Mellitus Tipo 1 , Hipoglicemia , Atividades Cotidianas , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Sistemas de Infusão de Insulina
16.
Front Plant Sci ; 11: 1078, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32765561

RESUMO

Defoliator insects are a major disturbance agent in many forests worldwide. During outbreaks, they can strongly reduce photosynthetic carbon uptake and impact tree growth. In the Alps, larch budmoth (Zeiraphera diniana) outbreaks affect European larch (Larix decidua) radial growth over several years. However, immediate and legacy effects on xylem formation, structure, and functionality are still largely unknown. In this study, we aimed at assessing the impact of budmoth defoliations on larch xylem anatomical features and tree-ring structure. Analyses were performed in the Lötschental (Swiss Alps) within (1,900 m a.s.l.) and above (2,200 m a.s.l.) the optimum elevational range of larch budmoth. We investigated variability of xylem anatomical traits along century-long tree-ring series of larch (host) and Norway spruce (non-host) trees. We identified eight outbreaks affecting larch xylem anatomy during the 20th century, particularly at 1,900 m a.s.l. Tracheid number always showed a higher percent reduction than properties of individual cells. Cell lumen size was slightly reduced in the first 2-3 years of outbreaks, especially in the early part of the ring. The more carbon-demanding cell wall was thinned along the entire ring, but more evidently in the last part. Theoretical tree-ring hydraulic conductivity was reduced for several years (up to 6), mostly due to cell number decrease. Reduced cell wall area and cell number resulted in a strong reduction of the tree-ring biomass, especially in the first year of outbreak. Our study shows that, under carbon source limitations caused by natural defoliation, cell division is more impacted than wall thickening and cell enlargement (the least affected process). Consequences on both xylem hydraulic properties and tree-ring biomass should be considered when assessing long-term defoliator effects on xylem functioning, forest dynamics, and terrestrial carbon cycle.

17.
Tree Physiol ; 40(12): 1668-1679, 2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-32785622

RESUMO

The performance and distribution of woody species strongly depend on their adjustment to environmental conditions based on genotypic and phenotypic properties. Since more intense and frequent drought events are expected due to climate change, xylem hydraulic traits will play a key role under future conditions, and thus, knowledge of hydraulic variability is of key importance. In this study, we aimed to investigate the variability in hydraulic safety and efficiency of the conifer shrub Juniperus communis based on analyses along an elevational transect and a common garden approach. We studied (i) juniper plants growing between 700 and 2000 m a.s.l. Innsbruck, Austria, and (ii) plants grown in the Innsbruck botanical garden (Austria) from seeds collected at different sites across Europe (France, Austria, Ireland, Germany and Sweden). Due to contrasting environmental conditions at different elevation and provenance sites and the wide geographical study area, pronounced variation in xylem hydraulics was expected. Vulnerability to drought-induced embolisms (hydraulic safety) was assessed via the Cavitron and ultrasonic acoustic emission techniques, and the specific hydraulic conductivity (hydraulic efficiency) via flow measurements. Contrary to our hypothesis, relevant variability in hydraulic safety and efficiency was neither observed across elevations, indicating a low phenotypic variation, nor between provenances, despite expected genotypic differences. Interestingly, the provenance from the most humid and warmest site (Ireland) and the northernmost provenance (Sweden) showed the highest and the lowest embolism resistance, respectively. The hydraulic conductivity was correlated with plant height, which indicates that observed variation in hydraulic traits was mainly related to morphological differences between plants. We encourage future studies to underlie anatomical traits and the role of hydraulics for the broad ecological amplitude of J. communis.


Assuntos
Juniperus , Áustria , Secas , Europa (Continente) , França , Alemanha , Juniperus/genética , Água , Xilema
18.
Acta Biomed ; 91(6-S): 48-64, 2020 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-32573506

RESUMO

BACKGROUND: The transition of medical care from a pediatric to an adult environment is a psychological change, a new orientation that requires a self-redefinition of the individual, to understand that changes are taking place in his life. Up to 60 percent of pediatric patients who transition to adult services will experience one or more disease or treatment-related complication as they become adults. A nurse who knows how to recognize potential barriers at an early stage can play a pivotal role in the educational plan for the transition process. MATERIALS AND METHODS: A literature search was undertaken of PUBMED, CINAHL and The Cochrane Library, with specific inclusion and exclusion criteria, including articles published in the lasts ten years.This literature review has been performed according to the PRISMA statement. RESULTS: Using the keywords in different combination 38 articles were found in The Cochrane Library, 5877 in PUBMED, 274 in CINAHL. 88 articles were selected after the abstract screening. 31 after removing the duplicates and reading the full text. DISCUSSION: The main themes surrounding transition of care that emerged from the synthesis are the organization of care within common models of transition, innovative clinical approaches to transition, and the experience of patients and caregivers. The transition from pediatric to adult care of cancer or SCD survivors is an emerging topic in pediatric nursing. The organization of care is affected by the lack of clear and well-structured organizational models. Further research is needed to deepen the understanding of some aspects of the transition.


Assuntos
Neoplasias Hematológicas , Papel do Profissional de Enfermagem , Enfermagem Pediátrica , Transição para Assistência do Adulto , Adolescente , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Neoplasias Hematológicas/terapia , Humanos , Modelos Organizacionais , Transição para Assistência do Adulto/organização & administração
19.
Sci Total Environ ; 682: 171-179, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31112818

RESUMO

High latitude and altitude environments are universally recognized as particularly sensitive to environmental changes and the current climate warming is inducing remarkable transformations on vegetation assemblage in these temperature-limited regions. However, next to the wealth of studies describing the effect of rising growing season temperature on trees, much less is known about the concurrent effects of precipitation and snowpack dynamics on the other key component of alpine vegetation represented by prostrate life forms. Selecting the most widespread shrub species in the North Hemisphere, we assembled a monospecific (Juniperus communis L.) network of 7 sites overarching the European Alps, measured the annual growth on >330 individuals and assessed the climate-growth associations for the last century (1910-2010) adopting a new model estimating the solid fraction of precipitation from unique highly-resolved daily climate records. Despite the high space-time variability of the yearly precipitation amount and distribution across the region, our analysis found a prominent, consistent and negative role of winter precipitation for shrub growth. Moreover, this crucial role of snow is maintained even in recent years, despite the persistent and significant warming trend. The presence of this underrated key factor for Alpine long-lived vegetation will require a thorough consideration. For the prostrate life form, not only temperature but also the solid fraction of winter precipitation should be considered to improve the projections of future growth trajectories.


Assuntos
Juniperus/crescimento & desenvolvimento , Neve , Temperatura , Árvores/crescimento & desenvolvimento , Altitude , Clima , Mudança Climática , Itália , Estações do Ano
20.
Acta Biomed ; 90(4-S): 74-78, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30977751

RESUMO

BACKGROUND AND AIM OF THE WORK: There is evidence in adult literature that the enema in the preoperative of thoracic surgery can be dismissed without disadvantage. However, there is a gap of articles about enema in childhood for thoracic surgeries. The aim of the work is  to investigate whether the administration of enema in the preparation for cardiac surgery, the use of different analgosedation drugs and the Extracorporeal Circulation influence the children's intestinal motility in the post-operative period. METHODS: A retrospective study was carried out comparing the data between users subjected to saline solution enema, originating from the U.O.C. of Pediatric Cardiology and Pediatric Cardiac Surgery and Congenital Heart Disease and users not subjected to such procedure, coming from the U.O.S.D. Pediatric Intensive Care. The data collected will evaluate the intestinal motility in the post-operative cardiac surgery. RESULTS: The following three variables were analyzed: interval of post-operative evacuation days (mean 2.14, median 2.00, standard deviation 1.525 in non-enema children; mean 2.76, median 2.00, standard deviation 1.318 in enema children), administered analgosedation drugs and use of Extracorporeal Circulation - for which the Pearson Test was used. A sampling bias is also reported from the analysis of the data. The study did not show a statistical significance correlates the variables analyzed to intestinal motility in post-operative period. CONCLUSION: The sampling bias emerged could reflect the diversity of the catchment area in the two Wards. The study - in agreement with the literature concerning the adult user - proves that the practice of enema evacuation pre-operative cardiac surgery in the pediatric user is unnecessary and does not influence intestinal transit in the post-operative period.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Enema , Cuidados Pré-Operatórios/métodos , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos
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