We investigated the role of fire in controlling bush thickening in arid savannas. Three controlled fires were initiated to investigate the responses of planted seedlings, saplings and mature shrubs. ...The stem diameters of seedlings, saplings and mature shrubs prior to the fire were measured. Other dimensions of the saplings and mature shrubs such as leaf mass were also estimated. The intensity of each fire was estimated. Fire temperatures adjacent to seedlings saplings and mature shrubs were measured using fire paints on steel plates. All three fires were moderately hot. One year after each fire, the mortality of seedlings in the fire treatments was very high (97.1–99.3%) and significantly greater than in adjacent controls (16.1–51.6%). Mortality and topkill of saplings and mature shrubs were negatively related to stem diameter. Fire temperature did not significantly affect mortality and topkill in most cases. Surviving saplings showed a much greater resprout response, relative to pre fire size, than larger shrubs and trees. Our results suggest that fire is crucial in interrupting the transition from open grassy savanna to thicket in arid savannas. Managers who prevent fires at this stage are likely to experience bush thickening in the future.
► We studied the effects of fire on Acacia mellifera in an arid savanna. ► Almost all seedlings were killed by the fire. ► Survived saplings resprouted and regrew rapidly after the fire. ► Most mature shrubs resprouted and almost all survived. ► Fires coinciding with establishment events maintain arid savannas in an open state.
Background
Treatment of patients with hemophilia has advanced over the past decades, but it is unknown whether this has resulted in a normal life expectancy in the Netherlands.
Objective
This ...observational cohort study aimed to assess all‐cause and cause‐specific mortality in patients with hemophilia in the Netherlands between 2001 and 2018 and to compare mortality and life expectancy with previous survival assessments from 1973 onward.
Patients/methods
All 1066 patients with hemophilia who participated in a nationwide survey in 2001 were followed until July 2018.
Results
Information on 1031 individuals (97%) was available, of whom 142 (14%) deceased during follow‐up. Compared with the general Dutch male population, mortality of patients with hemophilia was still increased (standardized mortality ratio: 1.4, 95% confidence interval: 1.2–1.7). Intracranial bleeding and malignancies were the most common causes of death. Estimated median life expectancy of patients with hemophilia was 77 years, 6 years lower than the median life expectancy of the general Dutch male population (83 years). Over the past 45 years, death rates of patients with hemophilia have consistently decreased, approaching the survival experience of the general population. Over the past decades, mortality due to human immunodeficiency virus and hepatitis C virus infections has decreased, death due to intracranial hemorrhages has increased, and death due to ischemic heart disease has remained consistently low over time.
Conclusions
Survival in patients with hemophilia in the Netherlands has improved over time but is still lower than that of the general population.
Seed production and seedling survival are under-researched in savannas. We investigated these in a population of a major thickening species, Acacia mellifera, in an arid Namibian savanna over a nine ...year period (late 1998–early 2007) We asked the following questions: (i) How does viable seed production vary with rainfall and tree size, (ii) when does seed germination occur, (iii) is the seed bank of A. mellifera persistent, and (iv) how do competitive interactions with established trees influence recruitment of A. mellifera seedlings? Seed production was highly correlated with annual rainfall. In dry years, there was no viable seed production. En masse seed production only occurred in exceptionally high rainfall years, and was strongly correlated with size among trees >2 m tall. Seed predation was low. Seedlings only emerged directly after en masse seed production, suggesting ephemeral seed banks. Three times more seedlings emerged per m2, but seedling survival was five times less, under trees than away from trees, indicating strong competition for water with established trees. Seed production is a recruitment bottleneck in this species. Recruitment requires at least two consecutive seasons of favourable rainfall, and is highly episodic in arid savannas.
► We studied a population of Acacia mellifera shrubs in an arid savanna over 10 years. ► Seed production was highly correlated with rainfall and tree size. ► Trees only produced seeds en masse in exceptionally high rainfall years. ► Seeds germinate only in seasons when seeds are produced. ► Consequently establishment requires protracted periods of high rainfall events.
Internet-based interventions are seen as an important potential strategy to improve accessibility and affordability of high quality treatments in mental healthcare. A growing number of studies have ...demonstrated the clinical efficacy of internet-based treatment for mood disorders, but scientific evidence for the application in routine specialised mental healthcare settings is limited. Also, little is known about the clinical and health-economic benefits of blended treatment, where online interventions are integrated with face-to-face treatment of depression in one treatment protocol. The primary aim of this study is to investigate the clinical and cost-effectiveness of blended Cognitive Behavioural Therapy (bCBT) for depression, as compared to treatment as usual (TAU) in specialised routine mental healthcare in the Netherlands. This trial is part of the E-COMPARED project which has a broader perspective, focussing on primary and specialised care in eight European countries.
The study is a randomised controlled non-inferiority trial with two parallel conditions: bCBT and TAU. The blended treatment combines individual face-to-face CBT with CBT delivered through an Internet-based treatment platform (Moodbuster). This platform includes a mobile phone application, used for ecological momentary assessments, automated feedback and motivational messages. Weekly alternating face-to-face (10) and online (9) sessions will be delivered over a period of 19-20 weeks. TAU is defined as the routine care that subjects receive when they are diagnosed with depression in specialised mental healthcare. Adult patients ≥ 18 years old meeting DSM-IV diagnostic criteria for major depressive disorder will be recruited within participating outpatient specialised mental healthcare clinics in the Netherlands. Measurements will be taken at baseline and at 3, 6 and 12 months follow-up. The primary outcome will be depressive symptoms, measured with the PHQ-9 and QIDS. Secondary outcomes include health-related quality of life, mastery, treatment preference, working alliance, system usability, treatment satisfaction and possible negative side-effects. Moreover, a cost-effectiveness analysis will be conducted from a societal perspective and will include both direct and indirect healthcare costs.
The results of this study will provide insight into the health and economical outcomes of blended treatment for depression and give an indication of the value of implementing blended treatment in specialised clinical settings.
Netherlands Trial Register NTR4962 . Registered 05-01-2015.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pygmy Dipole Response in Samarium isotopes Jivan, H; Pellegri, L; Adsley, P. ...
Journal of physics. Conference series,
09/2023, Letnik:
2586, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract
The influence of nuclear shape deformation on the Pygmy Dipole Response (PDR) was investigated using (α,α′γ) scattering on
144
Sm and
154
Sm. Experiments were conducted at iThemba LABS, ...coupling for the first time the K600 magnetic spectrometer with the BaGeL (Ball of Germanium and LaBr detectors) array. Preliminary results showcasing the efficacy of the facility and set-up for performing these 0° scattering experiments to investigate the PDR region are presented.
Introduction
We conducted six cross‐sectional nationwide questionnaire studies among all patients with hemophilia in the Netherlands from 1972 until 2019 to assess how health outcomes have changed, ...with a special focus on patients >50 years of age.
Methods
Data were collected on patient characteristics, treatment, (joint) bleeding, joint impairment, hospitalizations, human immunodeficiency virus and hepatitis C infections, and general health status (RAND‐36).
Results
In 2019, 1009 patients participated, of whom 48% had mild, 15% moderate, and 37% severe hemophilia. From 1972 to 2019, the use of prophylaxis among patients with severe hemophilia increased from 30% to 89%. Their median annual bleeding rate decreased from 25 to 2 bleeds. Patients with severe hemophilia aged <16 years reported joint impairment less often over time, but in those aged >40 years joint status did not improve. In 2019, 5% of all 1009 patients were positive for the human immunodeficiency virus. The proportion of patients with an active hepatitis C infection drastically decreased from 45% in 2001 to 2% in 2019 due to new anti‐hepatitis C treatment options. Twenty‐five percent had significant liver fibrosis even after successful therapy. Compared to the general male population, patients aged >50 years reported much lower scores on the RAND‐36, especially on physical functioning.
Discussion/Conclusion
Our study shows that increased use of prophylactic treatment and effective hepatitis C treatment have improved joint health and nearly eradicated hepatitis C infection in patients with hemophilia in the Netherlands. However, patients still suffer from hemophilia‐related complications, especially patients aged >50 years.
Purpose
The surgical navigation system that provides guidance throughout the surgery can facilitate safer and more radical liver resections, but such a system should also be able to handle organ ...motion. This work investigates the accuracy of intraoperative surgical guidance during open liver resection, with a semi‐rigid organ approximation and electromagnetic tracking of the target area.
Methods
The suggested navigation technique incorporates a preoperative 3D liver model based on diagnostic 4D MRI scan, intraoperative contrast‐enhanced CBCT imaging and electromagnetic (EM) tracking of the liver surface, as well as surgical instruments, by means of six degrees‐of‐freedom micro‐EM sensors.
Results
The system was evaluated during surgeries with 35 patients and resulted in an accurate and intuitive real‐time visualization of liver anatomy and tumor's location, confirmed by intraoperative checks on visible anatomical landmarks. Based on accuracy measurements verified by intraoperative CBCT, the system’s average accuracy was 4.0 ± 3.0 mm, while the total surgical delay due to navigation stayed below 20 min.
Conclusions
The electromagnetic navigation system for open liver surgery developed in this work allows for accurate localization of liver lesions and critical anatomical structures surrounding the resection area, even when the liver was manipulated. However, further clinically integrating the method requires shortening the guidance‐related surgical delay, which can be achieved by shifting to faster intraoperative imaging like ultrasound. Our approach is adaptable to navigation on other mobile and deformable organs, and therefore may benefit various clinical applications.
Namibian rangelands are encroached with
Acacia mellifera, partially resulting from a poor understanding of vegetation dynamics. A conceptual state-and-transition model of vegetation dynamics in the ...semiarid Highland savanna in central Namibia, emphasising bush thickening by
A. mellifera, is described. Two main states, a grassy and a bushy state, are identified. These are further subdivided, and 11 transitions are identified. The key transition initiating a change from grassy to bushy state can be termed a “leap” (an occasional, infrequent mass recruitment event) following a long “sleep” (no or little change in
A. mellifera density). It is rare because it requires three consecutive years of above-average rainfall for seedling establishment. Fire, coinciding with seedling establishment, can interrupt it, while a low biomass grass sward facilitates it. The phenology and physiology of the encroaching species, seed predation and sapling herbivory influence this transition. The model proposes opportunistic management interventions, particularly the use of fire, to minimise the risk of further landscape-scale transitions to a bushy state. It highlights areas where understanding of vegetation dynamics is lacking and recommends crucial research foci. Conceptual models of bush-thickening processes need to account for differences in climate and phenological details of encroaching species.
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