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Equatorial Kelvin waves (KWs) are associated with a variety of equatorial atmospheric phenomena. They are related to tropical convection, cloud and precipitation variability, tropical cyclogenisis, the onset of monsoon season over Africa and India, and even equatorial oscillation patterns, namely the quasi-biennial oscillation (QBO) and the Madden-Julian oscillation (MJO). As such, if operational forecasts are to improve near the tropics, it is important that they correctly represent KWs. This paper aims at developing a novel methodology for identifying KWs in real-time operational forecasts at specific longitudes using only the meridional structures of the solutions to the free Laplace tidal equations, known as Hough vector functions. The main advantages of this newly proposed methodology are that 1) it can univocally identify Kelvin waves at given longitudes and 2) very low computational cost is needed to apply it to real-time operational forecasts. The application of the method to 2015-2017 ECMWF analysis and operational forecast data reveals a topography related bias in the representation of the amplitude and phase of the Kelvin waves by the ECMWF operational forecast model.

Contains fulltext : 307395.pdf (Publisher’s version ) (Open Access), PURPOSE: The aim of this study was to investigate the biodistribution of (super-)selective trans-arterial radioembolization (TARE) with holmium-166 microspheres ((166)Ho-MS), when administered as adjuvant therapy after RFA of HCC 2-5 cm. The objective was to establish a treatment volume absorbed dose that results in an absorbed dose of ≥ 120 Gy on the hyperemic zone around the ablation necrosis (i.e., target volume). METHODS: In this multicenter, prospective dose-escalation study in BCLC early stage HCC patients with lesions 2-5 cm, RFA was followed by (super-)selective infusion of (166)Ho-MS on day 5-10 after RFA. Dose distribution within the treatment volume was based on SPECT-CT. Cohorts of up to 10 patients were treated with an incremental dose (60 Gy, 90 Gy, 120 Gy) of (166)Ho-MS to the treatment volume. The primary endpoint was to obtain a target volume dose of ≥ 120 Gy in 9/10 patients within a cohort. RESULTS: Twelve patients were treated (male 10; median age, 66.5 years (IQR, [64.3-71.7])) with a median tumor diameter of 2.7 cm (IQR, [2.1-4.0]). At a treatment volume absorbed dose of 90 Gy, the primary endpoint was met with a median absorbed target volume dose of 138 Gy (IQR, [127-145]). No local recurrences were found within 1-year follow-up. CONCLUSION: Adjuvant (super-)selective infusion of (166)Ho-MS after RFA for the treatment of HCC can be administered safely at a dose of 90 Gy to the treatment volume while reaching a dose of ≥ 120 Gy to the target volume and may be a favorable adjuvant therapy for HCC lesions 2-5 cm. TRIAL REGISTRATION: Clinicaltrials.gov NCT03437382 . (registered: 19-02-2018)., 01 juni 2024

Contains fulltext : 296077.pdf (Publisher’s version ) (Open Access), PURPOSE: To compare transarterial chemoembolization delivered with drug eluting beads (TACE-DEB) with stereotactioc body radiation therapy (SBRT) in patients with hepatocellular carcinoma (HCC) in a multicenter randomized trial. METHODS AND MATERIALS: Patients were included if they were eligible for TACE. They could also be recruited if they required treatment prior to liver transplantation. A maximum of four TACE-DEB procedures and ablation after incomplete TACE-DEB were both allowed. SBRT was delivered in six fractions of 8-9Gy. Primary end point was time to progression (TTP). Secondary endpoints were local control (LC), overall survival (OS), response rate (RR), toxicity, and quality of life (QoL). The calculated sample size was 100 patients. RESULTS: Between May 2015 and April 2020, 30 patients were randomized to the study. Due to slow accrual the trial was closed prematurely. Two patients in the SBRT arm were considered ineligible leaving 16 patients in the TACE-DEB arm and 12 in the SBRT arm. Median follow-up was 28.1 months. Median TTP was 12 months for TACEDEB and 19 months for SBRT (p=0.15). Median LC was 12 months for TACE-DEB and >40 months (not reached) for SBRT (p=0.075). Median OS was 36.8 months for TACEDEB and 44.1 months for SBRT (p=0.36). A post-hoc analysis showed 100% for SBRT 1- and 2-year LC, and 54.4% and 43.6% for TACE-DEB (p=0.019). Both treatments resulted in RR>80%. Three episodes of possibly related toxicity grade ≥3 were observed after TACE-DEB. No episodes were observed after SBRT. QoL remained stable after both treatment arms. CONCLUSIONS: In this trial, TTP after TACE-DEB was not significantly improved by SBRT, while SBRT showed higher local antitumoral activity than TACE-DEB, without detrimental effects on OS, toxicity and QoL. To overcome poor accrual in randomized trials that include SBRT, and to generate evidence for including SBRT in treatment guidelines, international cooperation is needed.

Contains fulltext : 295976.pdf (Publisher’s version ) (Open Access), BACKGROUND: This study compares a comprehensive range of psychosocial outcomes of adult childhood cancer survivors (CCS) to general population-based references and identifies sociodemographic and medical risk factors. METHODS: CCS from the Dutch Childhood Cancer Survivor Study (DCCSS)-LATER cohort (diagnosed 1963-2001) part 2 (attained age ≥18 years, diagnosed <18 years, ≥5 years since diagnosis) completed the Rosenberg Self-Esteem Scale, Hospital Anxiety and Depression Scale, Distress Thermometer, Self-Rating Scale for Post-Traumatic Stress Disorder, and the Short Form-36 (Health Related Quality of Life). CCS' scores were compared with references using analysis of variances and logistic regression analysis, controlling for age and sex (p < .05). Risk factors for worse psychosocial outcomes were assessed with regression analyses (p < .05). RESULTS: CCS, N = 1797, mean age 35.4 years, 49.0% female, all ≥15 years since diagnosis, participated. Three percent reported posttraumatic stress disorder because of childhood cancer and 36.6% experienced clinical distress. CCS did not differ from references on self-esteem and anxiety but were less depressed (d = -.25), and scored poorer on all health-related quality of life scales, except for bodily pain (.01 ≤ d ≥ -.36). Female sex, lower educational attainment, not being in a relationship, and being unemployed were negatively associated with almost all psychosocial outcomes. Except for a central nervous system tumor diagnosis, few medical characteristics were associated with psychosocial outcomes. CONCLUSION: CCS appear resilient regarding mental health but have slightly poorer health-related quality of life than references. Sociodemographic characteristics and central nervous system tumors were related to most psychosocial outcomes, but no clear pattern was observed for other medical factors. Future studies should address additional factors in explaining CCS' psychosocial functioning, such as coping, social support, and ph

Background: Goal-setting is an approach that encourages the use of self-defined goals of care in the process of decision-making. It is already a commonly known concept in rehabilitation and end-of life care. Several positive effects have been listed in previous research. At University Medical Center Utrecht it appears that only few doctors document goals of care in patient records. This study aims to identify stakeholders’ experiences with goal-setting and the barriers and facilitators to discussing, documenting and using goals of care in individual health care. Methods: A qualitative study design was used. In-depth topic-interviews were held with 19 healthcare professionals (HCPs) and 7 patients. Results: Although the majority of HCPs and patients share a positive attitude towards goal-setting, it appears hard to accomplish. This study identified that that most HCPs are not consistent in discussing values, preferences and goals with their patients. Many different barriers to goalsetting are identified, including the ambiguity concerning the interpretation of goals, organisational barriers, patient-related barriers and the uncertainty about the usefulness and feasibility of goal-setting in every setting or situation. Most stakeholders agree that the current methods of goal-setting are not adequate. Conclusion: Based on our findings, the formulation of purely medical goals might be useful to improve communication between HCPs and provide clarity to patients. However, purely medical goals attribute less to performing care that is person-centered. Further research is recommended to identify ways to overcome the barriers and to develop a strategy for meaningful goal-setting in different care settings.

This thesis provides an epistemological and ethical analysis of the use of the concepts ‘experience’, ‘experiential knowledge’ and ‘experiential expertise’ within patient participation in The Netherlands. It shows how the use of these concepts can provoke epistemic injustice being done to patients by creating hierarchies of epistemic positions and by exclusion of marginalised groups. It is argued that instead of experiential knowledge, we should start using the term ‘patient knowledge’. In order to do this it is examined whether a capabilities approach could be a suitable theoretical framework to involve patient knowledge into care in a morally just way. Therefore, three arguments in favour of– and against– a capabilities approach are introduced, exploring if it can provide an equitable design for reshaping patient participation policies within The Netherlands. It was concluded that an essentialist capabilities approach can provide an equitable framework for patient participation on an institutional (macro) level. At an individual (micro) level, it can provide a starting point for the conversation between physicians and patients, but leaves the freedom to interpret the framework to the patient and the physician. The task of the physicians is to create the space for good communication, by, for instance, using tools as a prelude for the conversation or by the acquisition of both moral and epistemic virtues.

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Contains fulltext : 252031.pdf (Publisher’s version ) (Open Access), PURPOSE: The primary objective is to determine the minimal ablation margin required to achieve a local recurrence rate of < 10% in patients with hepatocellular carcinoma undergoing thermal ablation. Secondary objectives are to analyze the correlation between ablation margins and local recurrence and to assess efficacy. MATERIALS AND METHODS: This study is a prospective, multicenter, non-experimental, non-comparative, open-label study. Patients > 18 years with Barcelona Clinic Liver Cancer stage 0/A hepatocellular carcinoma (or B with a maximum of two lesions < 5 cm each) are eligible. Patients will undergo dual-phase contrast-enhanced computed tomography directly before and after ablation. Ablation margins will be quantitatively assessed using co-registration software, blinding assessors (i.e. two experienced radiologists) for outcome. Presence and location of recurrence are evaluated independently on follow-up scans by two other experienced radiologists, blinded for the quantitative margin analysis. A sample size of 189 tumors (~ 145 patients) is required to show with 80% power that the risk of local recurrence is confidently below 10%. A two-sided binomial z-test will be used to test the null hypothesis that the local recurrence rate is >/= 10% for patients with a minimal ablation margin >/= 2 mm. Logistic regression will be used to find the relationship between minimal ablation margins and local recurrence. Kaplan-Meier estimates are used to assess local and overall recurrence, disease-free and overall survival. DISCUSSION: It is expected that this study will result in a clear understanding of the correlation between ablation margins and local recurrence. Using co-registration software in future patients undergoing ablation for hepatocellular carcinoma may improve intraprocedural evaluation of technical success. Trial registration The Netherlands Trial Register (NL9713), https://www.trialregister.nl/trial/9713 .

Background: To investigate whole-body contrast-enhanced CT and hepatobiliary contrast liver MRI for the detection of extrahepatic disease (EHD) in hepatocellular carcinoma (HCC) and to quantify the impact of EHD on therapy decision. Methods: In this post-hoc analysis of the prospective phase II open-label, multicenter, randomized controlled SORAMIC trial, two blinded readers independently analyzed the whole-body contrast-enhanced CT and gadoxetic acid-enhanced liver MRI data sets of 538 HCC patients. EHD (defined as tumor manifestation outside the liver) detection rates of the two imaging modalities were compared using multiparametric statistical tests. In addition, the most appropriate treatment recommendation was determined by a truth panel. Results: EHD was detected significantly more frequently in patients with portal vein infiltration (21% vs. 10%, p < 0.001), macrovascular infiltration (22% vs. 9%, p < 0.001), and bilobar liver involvement (18% vs. 9%, p = 0.006). Further on, the maximum lesion diameter in patients with EHD was significantly higher (8.2 cm vs. 5.8 cm, p = 0.002). CT detected EHD in significantly more patients compared to MRI in both reader groups (p < 0.001). Higher detection rates of EHD in CT led to a change in management only in one patient since EHD was predominantly present in patients with locally advanced HCC, in whom palliative treatment is the standard of care. Conclusions: Whole-body contrast-enhanced CT shows significantly higher EHD detection rates compared to hepatobiliary contrast liver MRI. However, the higher detection rate did not yield a significant impact on patient management in advanced HCC.

Crises worden gekenmerkt door dreiging, urgentie en onzekerheid. Ze kunnen voor komen in acute of in sluipende vorm. De sluipende crisis, waarbij de temporele factor anders ligt dan bij een acute crisis, wordt vaak minder urgent geacht, waardoor een treffende aanpak uitblijft. Over het treffend aanpakken van een sluipende crisis is relatief weinig bekend binnen de literatuur. Het is interessant om te onderzoeken of het creëren van langetermijnbeleid kan helpen bij de aanpak van een sluipende crisis, vanwege het vergelijkbare temporele aspect: gericht op een ruime tijdshorizon. Het ontwikkelen van langetermijnbeleid is geen gemakkelijke opgave, maar niet onmogelijk. Vier factoren die het ontwikkelen van dergelijk beleid bevorderen worden besproken in dit onderzoek: electorale zekerheid, zicht op winsten van het beleid, institutionele capaciteit en framing. Mogelijk kan er bij de aanpak van een sluipende crisis worden geleerd van de ontwikkeling van langetermijnbeleid. Dit vraagstuk staat centraal in dit onderzoek. Door middel van een kwalitatieve casestudy is gekeken in hoeverre inzichten over het creëren van langetermijnbeleid kunnen helpen bij de aanpak van een sluipende crisis. Deze vraag is onderzocht aan de hand van de casus ‘droogte in de Achterhoek’. Droogte in de Achterhoek kan worden beschouwd als een sluipende crisis. De aanpak krijgt vorm via een samenwerking tussen 19 partijen, bestaande uit onder andere provincie, gemeenten, waterschap en verschillende belangenorganisaties. Uit het onderzoek blijkt dat twee van de factoren die van invloed zijn op het creëren van langetermijnbeleid zeer relevant zijn (of minstens kunnen zijn) voor de aanpak van droogte in de Achterhoek: framing en capaciteit. Framing wordt niet bewust ingezet, maar er wordt bewust gewerkt aan beeldvorming en bepaalde woorden worden bewust gekozen of weggelaten. Bij capaciteit speelt in de Achterhoek voornamelijk het tekort aan goed personeel. De andere twee factoren bleken (op dit moment)

Introduction: Person-centred care is considered to be the core of healthcare, drawing attention to values and preferences of patients regarding their healthcare. Person-centred care plays an equally important role in paediatric healthcare, particularly in potential additional communicative difficulties for paediatric patients to convey their wishes. Implementation of the questionnaire ‘’We would like to know you!’’ aims to support person-centred care for paediatric patients. This study investigates the user experience of the questionnaire and the extent to which it supports person-centred care from the perspective of the healthcare professional. Method: A retrospective interview content analysis was conducted, using a qualitative narrative research method. Healthcare professionals were interviewed according to a topic list. Results: Eleven healthcare professionals were interviewed, including doctors, nurses and educational workers. The questionnaire’s overall use indicated a low level of application, partly due to its’ early stage of implementation and the choice to approach only new patients. However, the majority of those utilizing the questionnaire found it practical in use, providing additional information in either getting to know their patient, facilitate contact or as a way of being alerted of children or topics in need of additional attention during consultation. Conclusion: Based on these findings, the questionnaire could contribute to supporting more person-centred care. However, when primarily approached as a tool to improve efficiency in healthcare, person-centred care could be diminished. Future research is recommended on a larger group of participants, further identifying the various ways the questionnaire is utilized to support its’ aim of more person-centred care.

Regreening initiatives are being undertaken as climate change mitigation strategies, to improve water and food security, and to increase biodiversity. Because of positive feedback loops between vegetation and precipitation, regreening has the potential to lead to the restoration of local and regional water cycles. However, in arid and hyper-arid regions, the amount of available rainwater is not sufficient to sustain the initial stages of regreening. A technology that uses solar energy to evaporate seawater may be able to enhance convective rainfall. The main research question is: Can evaporation through technology potentially be used for water cycle restoration in arid and hyper-arid regions? Using atmospheric boundary layer theories as described by Stull (1988), a simple atmospheric column model was developed and coupled to a surface model with a dynamic vegetation component. Results of sensitivity analyses with this numerical model show the importance of atmospheric conditions and it is found that evaporation through technology has the potential to be effective in regions with a relatively moist and cold atmosphere. Regions that satisfy these conditions and also have a dry soil are mostly found 25-35°N near coasts and/or in mountainous areas. One such area is the Sinai Peninsula. Numerical simulations using ERA5 reanalysis data as boundary conditions show that the evaporation technology can increase precipitation locally, but this increase is small. However, because of the wind directed southward and up the mountain range of South Sinai, the technology has the potential to cause precipitation non-locally as well as is shown by simulations where the atmospheric column is moved along a streamline. In conclusion, enhanced evaporation through technology has the potential to be used for regreening projects if atmospheric conditions are favorable. However, more research is needed and the potential adverse effects, such as warming, need to be taken into consideration.

01 december 2021, Contains fulltext : 244864.pdf (Publisher’s version ) (Open Access), BACKGROUND: A uniform treatment strategy for patients suffering from early recurrence after local treatment of CRLM is currently lacking. The aim of this observational cohort study was to assess the potential survival benefit of repeat local treatment compared to systemic therapy in patients suffering from early recurrence of CRLM. PATIENTS AND METHODS: Patients who developed recurrent CRLM within 12 months after initial local treatment with curative intent were retrospectively identified in Amsterdam University Medical Centers between 2009-2019. Differences in overall and progression-free survival among treatment strategies were assessed using multivariable Cox regression analyses. RESULTS: A total of 135 patients were included. Median overall survival of 41 months [range 4-135] was observed in patients who received repeat local treatment, consisting of upfront or repeat local treatment after neoadjuvant systemic therapy, compared to 24 months [range 1-55] in patients subjected to systemic therapy alone (adjusted HR = 0.42 [95%-CI: 0.25-0.72]; P = .002). Prolonged progression-free survival was observed after neoadjuvant systemic therapy followed by repeat local treatment, as compared to upfront repeat local treatment in patients with recurrent CRLM within 4 months following initial local treatment of CRLM (adjusted HR = 0.36 [95%-CI: 0.15-0.86]; P = .021). CONCLUSION: Patients with early recurrence of CRLM should be considered for repeat local treatment strategies. A multimodality approach, consisting of neoadjuvant systemic therapy followed by repeat local treatment, appeared favorable in patients with recurrence within 4 months following initial local treatment of CRLM.

Contains fulltext : 245168.pdf (Publisher’s version ) (Open Access)

Contains fulltext : 239066.pdf (Publisher’s version ) (Open Access), BACKGROUND: Approximately 80% of patients with locally advanced pancreatic cancer (LAPC) are treated with chemotherapy, of whom approximately 10% undergo a resection. Cohort studies investigating local tumor ablation with radiofrequency ablation (RFA) have reported a promising overall survival of 26-34 months when given in a multimodal setting. However, randomized controlled trials (RCTs) investigating the effect of RFA in combination with chemotherapy in patients with LAPC are lacking. METHODS: The "Pancreatic Locally Advanced Unresectable Cancer Ablation" (PELICAN) trial is an international multicenter superiority RCT, initiated by the Dutch Pancreatic Cancer Group (DPCG). All patients with LAPC according to DPCG criteria, who start with FOLFIRINOX or (nab-paclitaxel/)gemcitabine, are screened for eligibility. Restaging is performed after completion of four cycles of FOLFIRINOX or two cycles of (nab-paclitaxel/)gemcitabine (i.e., 2 months of treatment), and the results are assessed within a nationwide online expert panel. Eligible patients with RECIST stable disease or objective response, in whom resection is not feasible, are randomized to RFA followed by chemotherapy or chemotherapy alone. In total, 228 patients will be included in 16 centers in The Netherlands and four other European centers. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, RECIST response, CA 19.9 and CEA response, toxicity, quality of life, pain, costs, and immunomodulatory effects of RFA. DISCUSSION: The PELICAN RCT aims to assess whether the combination of chemotherapy and RFA improves the overall survival when compared to chemotherapy alone, in patients with LAPC with no progression of disease following 2 months of systemic treatment. TRIAL REGISTRATION: Dutch Trial Registry NL4997 . Registered on December 29, 2015. ClinicalTrials.gov NCT03690323 . Retrospectively registered on October 1, 2018.

De temperatuur in West-Europa stijgt in april sneller dan jaargemiddeld. Bovendien warmt West-Europa in april sneller op dan andere gebieden op dezelfde breedtegraad, zoals Oost-Canada. In dit verslag bespreek ik of een toename van zuidelijke wind door versterking of oostelijke verschuiving van de trog van planetaire golven rond West-Europa als consequentie van veranderde sneeuwbedekking een oorzaak of gevolg is van de zonaal asymmetrische opwarming en de versterkte opwarming in april van West-Europa. Met behulp van hoofdcomponentanalyse blijkt er een zwak statistisch verband te zijn tussen (i) de temperatuur in West-Europa en de sneeuwbedekking op Eurazië en (ii) de temperatuur in Oost-Canada en sneeuwbedekking op Noord-Amerika. Door het weergeven van de zonaal gemiddelde v-component van de wind in april als functie van de lengtegraad, volgt dat er sprake is van een oostelijke verschuiving van het de trog boven de Atlantische oceaan. Er is geen tot weinig verschuiving van de trog in Oost-Canada. Daardoor is er sprake van meer zuidelijke wind in april in West-Europa. Door het bepalen van de lokale tijdafgeleide van de temperatuur blijkt echter dat de term afhankelijk van de meridionale snelheid juist afneemt met de tijd voor West-Europa. Zo volgt dat er sprake is van een longitudinaal homogenere temperatuurverdeling met de jaren waardoor de zuidelijke wind als gevolg van oostelijke verplaatsing van de trog niet de oorzaak kan zijn van de versterkte temperatuurtoename in West-Europa in april. Wel is er in april een toename gemeten van de verticale windsnelheid in De Bilt en Goose, welke wel een bijdrage levert aan de toegenomen temperaturen in april ten opzichte van het jaargemiddelde.

This study investigates how the loss in power production of offshore wind farms, caused by the wake effect, depends on the stability of the atmospheric boundary layer. A windfarm parameterization is used in HARMONIE-AROME, an operational numerical weather prediction model. Three experiments are performed — a control run without turbines, a default wind farm run with turbines installed until January 1 2019 and a future run that consist of a possible scenario for 2050 — in the German Bight for a selection of hours in2019, where wind direction ranges between 78.75-101.25°, wind speed from 8 to 16 m s-1 and the atmospheric boundary layer is considered unstable when RIB, the Bulk Richardson number, < 0, neutral when 0 ≤ RIB ≤ 0.2 or stable when RIB > 0.2. First the performance of the wind farm parameterization is evaluated with measurement of wind speed at FINO1, a research platform 45 km north of Borkum. We find that the default run performs better than the control run, as for all stabilities the bias and mean absolute error at 91 m and 34 m height are reduced. Then, the dependency of the wind farm wake on atmospheric stability is examined. We conclude that our method to define the wake area performs good and the wake area is larger in stable atmospheres where turbulent mixing is suppressed. Finally, the dependency of the power production loss on atmospheric stability is investigated. The median relative production loss for all wind farms under investigation combined is 31.5% for stable hours, 25.5% for neutral hours and 17% for unstable hours.

Although the density of observation sites is low on the East Antarctic Plateau, there are several locations at which meteorological observations are conducted. These observations provide insights into the local climate, and are invaluable for evaluating climate models and satellite observations. Additionally, the ERA5 reanalysis dataset from the European Centre for Medium-range Weather Forecasts (ECMWF) may enable these records to be extended with longer time series and far more complete spatial coverage, providing further insights into local climate conditions. The main purpose of this study is to obtain a better understanding of the variability and trends in local climate on the East Antarctic Plateau, and therefore better understand how conditions on the East Antarctic Plateau react to changes in climate. The first step toward this goal is to assess the agreement between observational records and ERA5 data for the parameters of interest – air temperature, surface pressure, and wind speed – in order to determine whether the ERA5 data are suitable for extending these records. The next step is to analyze the available data by examining climatological averages, comparing conditions at different sites, and investigating variability and trends. In the final step, local variables are examined in relation to indices representing two large-scale atmospheric flow patterns that are known to impact the Antarctic climate: the Southern Annular Mode (SAM) index and the Southern Oscillation Index (SOI). Despite the fact that comparisons between observations and ERA5 data are imperfect, there is often fairly good agreement between them, particularly for air temperature and surface pressure. While no statistically significant temporal trends are found in monthly mean (potential) temperature at any site for either observations or ERA5, some significant temporal trends are found for wind speed in both datasets at some sites, which could be connected to an upward trend in the SAM in