Are Ecosystem Engineering Traits Fixed or Flexible : A Study on Clonal Expansion Strategies in Co-occurring Dune Grasses

Many vegetated coastal ecosystems are formed through ecosystem engineering by clonal vegetation. Recent work highlights that the spatial shoot organization of the vegetation determines local sediment accretion and subsequently emerging landscape morphology. While this key engineering trait has been found to differ between species and prevailing environmental conditions, it remains unknown how the interplay of both factors drive shoot organization and therefore landscape morphology. Here, we compared the spatial shoot organization of young, clonally expanding plants of the two dominant European dune grass species: sand couch (Elytrigia juncea) and marram grass (Ammophila arenaria) across a range of coastal dune environments (from Denmark to France). Our results reveal that, on average, sand couch deployed a more dispersed shoot organization than marram grass, which has a patchy (Lévy-like) organization. Whereas sand couch exhibited the same expansion strategy independent of environmental conditions, marram grass demonstrated a large intraspecific variation which correlated to soil organic matter, temperature and grain size. Shoot patterns ranged from a clumped organization correlating to relatively high soil organic matter contents, temperature and small grain sizes, to a patchy configuration with intermediate conditions, and a dispersed organization with low soil organic matter, temperature and large grain size. We conclude that marram grass is flexible in adjusting its engineering capacity in response to environmental conditions, while sand couch instead follows a fixed expansion strategy, illustrating that shoot organization results from the interaction of both species-specific and environmental-specific trait expression

The effectiveness of a nurse-led intervention to support family caregivers in end-of-life care

__Aim:__ To evaluate the feasibility of a structured nurse-led supportive intervention and its effects on family caregivers in end-of-life care at home. __Background:__ Family caregivers are crucial in end-of-life care. They may experience burden due to the responsibilities associated with caregiving. Some family caregivers feel insufficiently prepared for their caregiver role. Nurses have a unique position to provide supportive interventions at home to reduce caregivers’ burden and improve preparedness. However, few nurse-led interventions are available to support family caregivers in end-of-life care at home. __Design:__ We will perform a cluster randomized controlled trial. The clusters consist of twelve home care services, randomly assigned to the intervention group or the control group. __Methods:__ The study population consists of family caregivers of patients in the last phase of life. In the intervention group, nurses will systematically assess the supportive needs of family caregivers, using an assessment tool and the method of clinical reasoning. Family members of the control group receive care as usual. Primary outcome is burden measured by the Self-Rated Burden Scale. Secondary outcomes are preparedness for caregiving, caregiving reactions and acute (hospital) admissions of the patient. In addition, the feasibility of the intervention will be evaluated. The study was funded in October 2016 and was ethically approved in April 2019. __Impact:__ Findings from this study will contribute to the scientific and practical knowledge of nursing interventions to support family caregivers in end-of-life care. Trial registration: The Netherlands Trial Register (NL7702)

The impact of comorbid chronic conditions on quality of life in type 2 diabetes patients

OBJECTIVE: To study the prevalence, impact and dose-response relationship of comorbid chronic conditions on quality of life of type 2 diabetes patients. RESEARCH DESIGN AND METHODS: Cross-sectional data of 1676 type 2 diabetes patients, aged 31-96 years, and treated in primary care, were analyzed. Quality of life (QoL) was measured using the mental component summary (MCS) and the physical component summary (PCS) scores of the Short Form-12. Diagnosis of type 2 diabetes was obtained from medical records and comorbidities from self-reports. RESULTS: Only 361 (21.5%) of the patients reported no comorbidities. Diabetes patients with comorbidities showed significantly lower mean difference in PCS [-8.5; 95% confidence interval (CI) -9.8 to -7.3] and MCS scores (-1.9; 95% CI -3.0 to -0.9), compared to diabetes patients without. Additional adjustments did not substantially change these associations. Both MCS and PCS scores decrease significantly with the number of comorbid conditions, yet most pronounced regarding physical QoL. Comorbidities that reduced physical QoL most significantly were retinopathy, heart diseases, atherosclerosis in abdomen or legs, lung diseases, incontinence, back, neck and shoulder disorder, osteoarthritis and chronic rheumatoid arthritis, using the backwards stepwise regression procedure. CONCLUSION: Comorbidities are highly prevalent among type 2 diabetes patients and have a negative impact on the patient's QoL. A strong dose-response relationship between comorbidities and physical QoL was found. Reduced physical QoL is mainly determined by musculoskeletal and cardiovascular disorders

Establishing cordgrass plants cluster their shoots to avoid ecosystem engineering

Vegetated coastal ecosystems such as salt marshes, dunes and seagrass meadows occur at the land–sea interface—a dynamic environment typified by harsh growing conditions. These ecosystems are known as biogeomorphic landscapes because their functioning depends on biophysical interactions by which organisms engineer landforms to their own benefit. The strength of such biogeomorphic feedbacks depends on plant traits, such as stem flexibility and shoot density. Recent work demonstrated that dune grasses with similar morphological traits can build contrasting landscapes due to differences in their spatial shoot organization. However, in contrast to dune grasses that trap and stabilize sand particles in aeolian landscapes, flow attenuation in aquatic environments can generate scouring around plant stems and cause uprooting, leading to establishment thresholds for young plants. Yet, it remains unknown how findings from aeolian landscapes translate to aquatic systems and how young clonally expanding plants in hydrodynamically exposed conditions overcome these establishment thresholds by optimizing shoot placement. Here, we measured shoot patterns of 90 establishing cordgrass patches Spartina anglica at 18 European field sites that cover a broad range of hydrodynamic conditions. Next, we carried out a field experiment to investigate how observed spatial shoot patterns affect plant–sediment feedbacks. Surprisingly, field survey analyses reveal highly consistent clustered shoot patterns, regardless of environmental conditions. Experimental results demonstrate that this clustered pattern minimizes scouring compared to densely clumped organizations typically observed in established patches. Synthesis. In contrast to earlier findings highlighting that establishing dune grasses optimize their landscape engineering capacity via a flexible shoot placement strategy, we find that cordgrass instead follows a fixed strategy that minimizes engineering effects in its early life stages. We suggest that marsh grasses avoid physical stress and associated establishment thresholds in their early life stage, and switch to an ecosystem engineering strategy once established. These findings shed new light on how plant traits interact with their environment to shape the landscape and pave the way for improved restoration designs by mimicking the natural shoot organization of establishing vegetation. Read the free Plain Language Summary for this article on the Journal blog.</p

Інноваційна конкурентоспроможність в умовах глобалізації

BACKGROUND Associations between acute respiratory inflammatory responses, changes in bronchial hyperresponsiveness, serum pneumoprotein levels, and exposure to fire smoke were studied. METHODS The study comprised 51 firefighters. Blood samples were taken within 24 hr following exposure to fire smoke, and after a week and 3 months. Sputum was induced within 5 days post-exposure and subjects underwent spirometry and methacholine provocation one week post-exposure. Exposure was registered by a questionnaire. RESULTS No changes were observed following smoke exposure in bronchial hyperresponsiveness and serum pneumoprotein levels. Nevertheless, in a sizable proportion of the firefighters (44%) elevated sputum neutrophil levels (≥60%) were found. Serum IL-8 concentrations were higher 24 hr post-exposure compared to pre-exposure. Elevated neutrophil levels in sputum were associated with elevated serum IL-8 (β = 0.010, P = 0.004) and TNFα (β = 0.005, P = 0.034) levels within 24 hr post-exposure and IL-8 elevation lasted up to 3 months. CONCLUSIONS Acute exposure to fire smoke induces acute neutrophilic airway and long-lasting systemic inflammation in healthy firefighters in the absence of bronchial hyperresponsiveness. Am. J. Ind. Med. 55:54-62, 2012. © 2011 Wiley Periodicals, Inc

Improving predictive performance on survival in dairy cattle using an ensemble learning approach

Cow survival is a complex trait that combines traits like milk production, fertility, health and environmental factors such as farm management. This complexity makes survival difficult to predict accurately. This is probably the reason why few studies attempted to address this problem and no studies are published that use ensemble methods for this purpose. We explored if we could improve prediction of cow survival to second lactation, when predicted at five different moments in a cow's life, by combining the predictions of multiple (weak) methods in an ensemble method. We tested four ensemble methods: majority voting rule, multiple logistic regression, random forest and naive Bayes. Precision, recall, balanced accuracy, area under the curve (AUC) and gains in proportion of surviving cows in a scenario where the best 50% were selected were used to evaluate the ensemble model performance. We also calculated correlations between the ensemble models and obtained McNemar's test statistics. We compared the performance of the ensemble methods against those of the individual methods. We also tested if there was a difference in performance metrics when continuous (from 0 to 1) and binary (0 or 1) prediction outcomes were used. In general, using continuous prediction output resulted in higher performance metrics than binary ones. AUCs for models ranged from 0.561 to 0.731, with generally increasing performance at moments later in life. Precision, AUC and balanced accuracy values improved significantly for the naive Bayes and multiple logistic regression ensembles in at least one data set, although performance metrics did remain low overall. The multiple logistic regression ensemble method resulted in equal or better precision, AUC, balanced accuracy and proportion of animals surviving on all datasets and was significantly different from the other ensembles in three out of five moments. The random forest ensemble method resulted in the least significant improvement over the individual methods

A 5-year follow-up study of Alfredson's heel-drop exercise programme in chronic midportion Achilles tendinopathy

Background: Eccentric exercises have the most evidence in conservative treatment of midportion Achilles tendinopathy. Although short-term studies show significant improvement, little is known of the long-term (>3 years) results. Aim: To evaluate the 5-year outcome of patients with chronic midportion Achilles tendinopathy treated with the classical Alfredson's heel-drop exercise programme. Study design: Part of a 5-year follow-up of a previously conducted randomised controlled trial. Methods: 58 patients (70 tendons) were approached 5 years after the start of the heel-drop exercise programme according to Alfredson. At baseline and at 5-year follow-up, the validated Victorian Institute of Sports Assessment-Achilles (VISA-A) questionnaire score, pain status, alternative treatments received and ultrasonographic neovascularisation score were recorded. Results: In 46 patients (58 tendons), the VISA-A score significantly increased from 49.2 at baseline to 83.6 after 5 years (p<0.001) and from the 1-year to 5-year follow-up from 75.0 to 83.4 (p<0.01). 39.7% of the patients were completely pain-free at follow-up and 48.3% had received one or more alternative treatments. The sagittal tendon thickness decreased from 8.05 mm (SD 2.1) at baseline to 7.50 mm (SD 1.6) at the 5-year follow-up (p=0.051). Conclusion: At 5-year follow-up, a significant increase of VISA-A score can be expected. After the 3-month Alfredson's heel-drop exercise programme, almost half of the patients had received other therapies. Although improvement of symptoms can be expected at long term, mild pain may remain