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The three-dimensional flow field past an I-shaped dual-step cylinder has been obtained by numerical integration of the Navier–Stokes equations at Reynolds number ($Re_D$) 150. The I-shaped cylinder consisted of two large-diameter (D) cylinders with a small-diameter (d) cylinder in between. With a view to exploring the vortex dynamics and structural loads, simulations were performed for eight different lengths $l$ of the small cylinder, varied from $l/D=10$ to 0.2 for a fixed diameter ratio $D/d=2$. When the length of the small cylinder is sufficiently large, the wake behind the I-shaped cylinder is similar to the wake behind the single-step cylinder (Tian et al., J. Fluid Mech., vol. 891, 2020, A24). As the small cylinder length decreases, the enhanced interactions between the two steps make the present wake deviate from the wake of the single-step cylinder, leading to four different wake modes distinguished by different combinations of vortex cells. The physical formation mechanisms were analysed in terms of the vortex dynamics. Besides the wake flow, the streamwise vortices around the I-shaped step cylinder were also investigated. A pair of edge vortices and a junction vortex were identified for $l/D \geq ~1$. When the gap between the two steps becomes too small, $l/D \leq ~0.2$, the junction vortex disappears, and only a pair of edge vortices exists. Varying the distance between the two steps strongly affects the structural loads (drag and lift) along the I-shaped cylinder. The dependence of the loads on $l/D$ was readily explained by the different wake modes.
Mainstream cognitive behavioural theory stipulates that clinically significant health anxiety persists over time at least partially due to negatively reinforced health-related behaviours, but there exists no broad and psychometrically valid measure of such behaviours.
Aims:
To draft and evaluate a new self-report scale – the Health Anxiety Behavior Inventory (HABI) – for the measurement of negatively reinforced health anxiety behaviours.
Method:
We drafted the HABI from a pool of 20 candidate items administered in a clinical trial at screening, and before and after cognitive behaviour therapy (n=204). A psychometric evaluation focused on factor structure, internal consistency, convergent and discriminant validity, test–retest reliability, and sensitivity to change.
Results:
Based on factor analysis, the HABI was completed as a 12-item instrument with a four-dimensional factor structure corresponding to the following scales: (i) bodily preoccupation and checking, (ii) information- and reassurance-seeking, (iii) prevention and planning, and (iv) overt avoidance. Factor inter-correlations were modest. The internal consistency (α=.73–.87) and 2-week test–retest reliability (r=.75–.90) of the scales was adequate. The bodily preoccupation and checking, and information- and reassurance-seeking scales were most strongly correlated with the cognitive and emotional components of health anxiety (r=0.41, 0.48), and to a lower extent correlated to depressive symptoms and disability. Change scores in all HABI scales correlated with improvement in the cognitive and emotional components of health anxiety during cognitive behaviour therapy.
Conclusions:
The HABI appears to reliably measure negatively reinforced behaviours commonly seen in clinically significant health anxiety, and might be clinically useful in the treatment of health anxiety.
Online treatments are increasing in number and are currently available for a wide range of clinical problems. To date little is known about the role of treatment expectations and other placebo-like mechanisms in online settings compared to traditional face-to-face treatment. To address this knowledge gap, we analyzed individual participant data from randomized clinical trials that compared online and face-to-face psychological interventions.
Methods
MEDLINE (Ovid) and PsycINFO (Ovid) were last searched on 2 February 2021. Randomized clinical trials of therapist guided online v. face-to-face psychological interventions for psychiatric or somatic conditions using a randomized controlled design were included. Titles, abstracts, and full texts of studies were independently screened by multiple observers. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was followed. Authors of the matching trials were contacted for individual participant data. Ratings from the Credibility and Expectancy Questionnaire and the primary outcome measure from each trial were used to estimate the association between expectation ratings and treatment outcomes in online v. face-to-face interventions, using a mixed-effects model.
Results
Of 7045 screened studies, 62 full-text articles were retrieved whereof six studies fulfilled the criteria and provided individual participant data (n = 491). Overall, CEQ ratings predicted clinical outcomes (β = 0.27) at end of treatment with no moderating effect of treatment modality (online v. face-to-face).
Conclusions
Online treatment appears to be equally susceptible to expectancy effects as face-to-face therapy. This furthers our understanding of the importance of placebo-like factors in online treatment and may aid the improvement of healthcare in online settings.
Bleeding control measures performed by members of the public can prevent trauma deaths. Equipping public spaces with bleeding control kits facilitates these actions. We modeled a mass casualty incident to investigate the effects of public bleeding control kit location strategies.
Methods:
We developed a computer simulation of a bomb exploding in a shopping mall. We used evidence and expert opinion to populate the model with parameters such as the number of casualties, the public’s willingness to aid, and injury characteristics. Four alternative placement strategies of public bleeding control kits in the shopping mall were tested: co-located with automated external defibrillators (AEDs) separated by 90-second walking intervals, dispersed throughout the mall at 10 locations, located adjacent to 1 exit, located adjacent to 2 exits.
Results:
Placing bleeding control kits at 2 locations co-located with AEDs resulted in the most victims surviving (18.2), followed by 10 kits dispersed evenly throughout the mall (18.0). One or 2 kit locations placed at the mall’s main exits resulted in the fewest surviving victims (15.9 and 16.1, respectively).
Conclusions:
Co-locating bleeding control kits with AEDs at 90-second walking intervals results in the best casualty outcomes in a modeled mass casualty incident in a shopping mall.
The vortex dynamics and the structural load in a step cylinder (consisting of a small, d, and a large, D, cylinder) flow are investigated numerically at Reynolds number ($Re_D$) 150 for diameter ratios $D/d=2.0, 2.4$ and 2.8. First, the formation mechanism of a non-uniform oblique vortex shedding (the vortex shedding frequency remains unchanged as the oblique shedding angle varies) behind the small cylinder is explained: an increase in the production rate of the vortex strength and a farther downstream movement of the vortex formation position occur simultaneously as the vicinity of the step is approached along the small cylinder. Second, the structural load (the drag and lift) along the step cylinder is investigated, where four local extremes (two local minima and two local maxima) are observed. An in-depth investigation of the vortex dislocation effects on the structural load is provided, showing that the decreased circulation in the near wake and the weakened staggered Kármán vortex shedding pattern cause a major reduction (90 %) of the sectional lift amplitude and a relatively modest reduction (5.7 %) of the sectional drag amplitude, compared with the corresponding sectional force when no vortex dislocation occurs. This new knowledge combined with the three-dimensional effect of the step cylinder wake (caused by the blending of the small and larger cylinder wakes around the step) explain the formation of the four local extremes and the distribution of the structural load between them. Finally, it is found that the increasing $D/d$ amplifies the structural load variation along the step cylinder.
Exposure to trauma is common and can have a profoundly negative impact on mental health. Interventions based on trauma-focused cognitive behavioural therapy have shown promising results to facilitate recovery. The current trial evaluated whether a novel, scalable and digital early version of the intervention, Condensed Internet-Delivered Prolonged Exposure (CIPE), is effective in reducing post-traumatic stress symptoms.
Method
A single-site randomised controlled trial with self-referred adults (N = 102) exposed to trauma within the last 2 months. The participants were randomised to 3 weeks of CIPE or a waiting list (WL) for 7 weeks. Assessments were conducted at baseline, week 1–3 (primary endpoint), week 4–7 (secondary endpoint) and at 6-month follow-up. The primary outcome measure was PTSD Checklist for DSM-5 (PCL-5).
Results
The main analysis according to the intention-to-treat principle indicated statistically significant reductions in symptoms of post-traumatic stress in the CIPE group as compared to the WL group. The between-group effect size was moderate at week 3 (bootstrapped d = 0.70; 95% CI 0.33–1.06) and large at week 7 (bootstrapped d = 0.83; 95% CI 0.46–1.19). Results in the intervention group were maintained at the 6-month follow-up. No severe adverse events were found.
Conclusions
CIPE is a scalable intervention that may confer early benefits on post-traumatic stress symptoms in survivors of trauma. The next step is to compare this intervention to an active control group and also investigate its effects when implemented in regular care.
Excessive worry is a common phenomenon. Our research group has previously developed an online intervention for excessive worry based on operant principles of extinction (IbET; internet-based extinction therapy) and tested it against a waiting-list. The aim of this study was to evaluate IbET against an active control comparator (CTRL).
Methods
A 10-week parallel participant blind randomised controlled trial with health-economical evaluation and mediation analyses. Participants (N = 311) were randomised (ratio 4.5:4.5:1) to IbET, to CTRL (an internet-based stress-management training program) or to waiting-list. The nation-wide trial included self-referred adults with excessive worry. The primary outcome was change in worry assessed with the Penn State Worry Questionnaire from baseline to 10 weeks.
Results
IbET had greater reductions in worry compared to CTRL [−3.6 point difference, (95% CI −2.4 to −4.9)] and also a significantly larger degree of treatment responders [63% v. 51%; risk ratio = 1.24 (95% CI 1.01–1.53)]. Both IbET and CTRL made large reductions in worry compared to waiting-list and effects were sustained up to 1 year. Treatment credibility, therapist attention, compliance and working alliance were equal between IbET and CTRL. Data attrition was 4% at the primary endpoint. The effects of IbET were mediated by the hypothesized causal mechanism (reduced thought suppression) but not by competing mediators. Health-economical evaluation indicated that IbET had a 99% chance of being cost-effective compared to CTRL given societal willingness to pay of 1000€.
Conclusions
IbET is more effective than active comparator to treat excessive worry. Replication and extensions to real-world setting are warranted.
The Stop the Bleed campaign in the United States aims to teach bleeding control techniques, such as tourniquets, to the public. Educational consortium guidelines advocate using brief web- or video-based material. Another option is posters or flyers distributed at, for example, workplaces or public spaces.
Aim:
The aim of the current study was to evaluate the relative efficacy between a flyer and a video to teach tourniquet application skills to members of the public in Sweden.
Methods:
A total of 38 participants (27 male, 11 female) from the general public completed the study. Their ages ranged from 19 to 73 (M=32, SD=14). None had prior experience with tourniquet applications. One group (n=18) received tourniquet instructions on a flyer and one (n=20) received a 5-minute video instruction. Both groups completed pre- and post-questionnaires and a practical tourniquet application test.
Results:
Independent samples t-tests showed that the video-based instructions resulted in fewer application errors (M=1.40 out of 10, SD=1.19) compared to the flyer group (M=3.61, SD=2.40), t(36)=3.651, p=0.001, and higher post-task satisfaction (M=3.89 out of 5, SD=0.74 compared to M=3.39, SD=1.15). However, the flyer-group was faster (M=86.22 seconds, SD=27.28) compared to the video group (M=112.25, SD=42.22), t(36)=2.229, p=0.032.
Discussion:
Video instructions appear superior to flyers in terms of teaching correct tourniquet application to the general public. The longer total application time includes steps taken after bleeding control has been achieved (e.g. securing tourniquet straps and time notation), which may have contributed to the application time difference. The results support the educational guidelines that suggest video-based instructions for teaching basic tourniquet skills to laypeople are more effective.
Internet-delivered cognitive behavioural therapy (ICBT) is a promising approach for increasing access to evidence-based treatments.
Aims
To develop and evaluate the feasibility and preliminary efficacy of an ICBT programme for young children with obsessive–compulsive disorder (OCD), named BIP OCD Junior.
Method
Eleven children aged 7–11 years were enrolled in a 12-week open trial of parent- and therapist-guided ICBT for OCD. The primary outcome measure was the Children's Yale–Brown Obsessive–Compulsive Scale (CY-BOCS).
Results
There was a significant improvement in OCD symptoms post-treatment, with a large within-group effect size on the CY-BOCS (Cohen's d = 1.86, 95% CI 0.83 to 2.86). Results were maintained at 3-month follow-up. Both children and parents rated the treatment as credible and were highly satisfied with the intervention.
Conclusions
BIP OCD Junior is a feasible and credible treatment option for young children with OCD. Randomised controlled trials are needed to further establish its efficacy and cost-effectiveness relative to gold standard face-to-face CBT.
Urban landscapes are highly heterogeneous and densely populated, and resources, responsibilities, rights and management capacities are distributed unequally among actors. People who want to engage in management of nearby spaces as stewards may not have the right to access those parts of the landscape, and they may lack the knowledge and skills needed to engage actively in hands-on management activities. Against this background, this chapter discusses a developing understanding of stewardship in urban landscapes grounded in literature and case studies on collaborations and civic mobilisation, their organisation and how they shape participation. Based on these explorations we argue that stewardship of urban landscapes needs to be understood as emerging from combinations of three components: i) The care, creativity and stewardship values connected to and present in local experiences and initiatives; 2) The combined knowledge and know-how held by different actors to steer activities towards a desire outcome; and 3) The agency, power and resources needed to negotiate and effect change. We suggest that landscape stewardship in cities often requires a collective effort in mobilising engagement, knowledge and funding in ways that generate legitimacy and political mandate and influence, without compromising the capacity to (co-) manage urban green and blue infrastructure.
Comparative models suggest that effects of dietary tryptophan (Trp) on brain serotonin (5-hydroxytryptamine; 5-HT) neurochemistry and stress responsiveness are present throughout the vertebrate lineage. Moreover, hypothalamic 5-HT seems to play a central role in control of the neuroendocrine stress axis in all vertebrates. Still, recent fish studies suggest long-term effects of dietary Trp on stress responsiveness, which are independent of hypothalamic 5-HT. Here, we investigated if dietary Trp treatment may result in long-lasting effects on stress responsiveness, including changes in plasma cortisol levels and 5-HT neurochemistry in the telencephalon and hypothalamus of Atlantic salmon. Fish were fed diets containing one, two or three times the Trp content in normal feed for 1 week. Subsequently, fish were reintroduced to control feed and were exposed to acute crowding stress for 1 h, 8 and 21 d post Trp treatment. Generally, acute crowding resulted in lower plasma cortisol levels in fish treated with 3×Trp compared with 1×Trp- and 2×Trp-treated fish. The same general pattern was reflected in telencephalic 5-HTergic turnover, for which 3×Trp-treated fish showed decreased values compared with 2×Trp-treated fish. These long-term effects on post-stress plasma cortisol levels and concomitant 5-HT turnover in the telencephalon lends further support to the fact that the extrahypothalamic control of the neuroendocrine stress response is conserved within the vertebrate lineage. Moreover, they indicate that trophic/structural effects in the brain underlie the effects of dietary Trp treatment on stress reactivity.
The use of Emergency Medical Services (EMS) is increasing. A number of patients call repeatedly for EMS. Early studies of frequent callers show that they form a heterogenous group.
Problem
There is a lack of research on frequent EMS callers. There is furthermore a lack of knowledge about characteristics and the prehospital assessment of the patients who call for EMS on several occasions. Finally, there is a general lack of knowledge with regard to the association between the prehospital assessment by health care providers and the final diagnosis.
Method
Patients in Skaraborg in Western Sweden, who used the EMS at least four times in 2014, were included, excluding transport between hospitals. Information on the prehospital assessment on-scene and the final diagnosis was collected from the EMS and hospital case records.
Results
In all, 339 individual patients who used the EMS on 1,855 occasions were included, accounting for five percent of all missions. Fifty percent were women. The age range was 10-98 years, but more than 50.0% were in the age range of 70-89 years.
The most common emergency signs and symptoms (ESS) codes on the scene were dyspnea, chest pain, and abdominal pain. The most common final diagnosis was chronic obstructive pulmonary disease (eight percent).
Thirteen percent of all cases had a final diagnosis defined as a potentially life-threatening condition. Among these, 22.0% of prehospital assessments were retrospectively judged as potentially inappropriate.
Forty-nine percent had a defined final diagnosis not fulfilling the criteria for a potentially life-threatening condition. Among these cases, 30.0% of prehospital assessments were retrospectively judged as potentially inappropriate.
Conclusion:
Among patients who used EMS on multiple occasions, the most common symptoms on-scene were dyspnea, chest pain, and abdominal pain. The most common final diagnosis was chronic obstructive pulmonary disease. In 13.0%, the final diagnosis of a potentially life-threatening condition was indicated. In a minority of these cases, the assessment on-scene was judged as potentially inappropriate.
TärnqvistJ, DahlénE, NorbergG, MagnussonC, HerlitzJ, StrömsöeA, AxelssonC, Andersson HagiwaraM. On-Scene and Final Assessments and Their Interrelationship Among Patients Who Use the EMS on Multiple Occasions. Prehosp Disaster Med. 2017;32(5):528–535.
By
Ronny Berndtsson, Center for Middle Eastern Studies, Lund University, Lund, Sweden, and Department of Water Resources Engineering, Lund University, Lund, Sweden,
Kaveh Madani, Centre for Environmental Policy, Imperial College London, London, UK,
Karin Aggestam, Peace & Conflict Studies, Lund University, Lund, Sweden,
Dan-Erik Andersson, Center for Middle Eastern Studies, Lund University, Lund, Sweden
The soon- to- be completed Grand Ethiopian Renaissance Dam (GERD) is abruptly modifying the hydropolitical map of the Nile Basin. Egypt, the historical hydro- hegemon that has preserved a strong position in the basin is challenged by Ethiopia, which seems to have decided to become a major African hydropower producer. Theoretical analysis indicates the risk for Egypt if it retaliates against Ethiopian intentions. However, it is obvious that retaliation does not lead to a sustainable future. Long- term sustainability includes collaboration between all riparians in the Nile Basin. Eventually, this will lead to greater prosperity for all involved countries and a more efficient use of the water but also a decrease in the flow of the Nile. Increasing the efficiency of water use means a larger volume of water for food production, better health of the population and sustainable economic development.
Introduction
In October 2014, the Ethiopian government announced that the Grand Ethiopian Renaissance Dam (GERD) was 40 percent complete. The dam will be the largest hydroelectric power plant and one of the largest reservoirs in Africa. The GERD will store a maximum of 74 km3 of water corresponding to a bit less than the average annual inflow of the Nile to the Aswan high dam (a total storage of about 84 km3). The dam surface area will be 1,680 km2 at full supply level. The project has foreseen a power plant capacity of 6,000 MW and 15,692 GWh annual energy amount. The GERD is vital for energy production and a key factor for food production, economic development and poverty reduction in Ethiopia and the Nile Basin. However, the GERD is also a political statement that has already largely rewritten the hydropolitical map of the Nile Basin. The GERD has become a symbol of Ethiopian nationalism, or “renaissance” (hidase in Amharic). Historically, the Nile Basin has witnessed a rivalry between Egypt and Ethiopia, on the one hand, but also uniting and cultural elements such as the relationships between the Coptic Church and the Orthodox Ethiopian Church on the other (e.g., Rubenson 2009). The Nile has also been the connecting link between Egypt and Ethiopia for thousands of years. Starting in the 3rd century, the Nile connected early Ethiopian Christianity with the Alexandrian Coptic Church, a link that continued uninterrupted for 1600 years (Ayele 1988, Erlich 2002).
In DSM-5 two new diagnoses, somatic symptom disorder (SSD) and illness anxiety disorder (IAD), have replaced DSM-IV hypochondriasis. There are no previous treatment studies for these disorders. Cognitive–behavioural therapy (CBT) delivered as therapist-guided or unguided internet treatment or as unguided bibliotherapy could be used to increase treatment accessibility.
Aims
To investigate the effect of CBT delivered as guided internet treatment (ICBT), unguided internet treatment (U-ICBT) and as unguided bibliotherapy.
Method
A randomised controlled trial (RCT) where participants (n = 132) with a diagnosis of SSD or IAD were randomised to ICBT, U-ICBT, bibliotherapy or to a control condition on a waiting list (trial registration: Clinicaltrials.gov identifier NCT01966705).
Results
Compared with the control condition, all three treatment groups made large and significant improvements on the primary outcome Health Anxiety Inventory (between-group d at post-treatment was 0.80–1.27).
Conclusions
ICBT, U-ICBT and bibliotherapy can be highly effective in the treatment of SSD and IAD. This is the first study showing that these new DSM-5 disorders can be effectively treated.
Exposure-based cognitive–behavioural therapy (CBT) delivered via the internet has been shown to be effective for severe health anxiety (hypochondriasis) but has not been compared with an active, effective and credible psychological treatment, such as behavioural stress management (BSM).
Aims
To investigate two internet-delivered treatments – exposure-based CBT v. BSM – for severe health anxiety in a randomised controlled trial (trial registration: NCT01673035).
Method
Participants (n = 158) with a principal diagnosis of severe health anxiety were allocated to 12 weeks of exposure-based CBT (n = 79) or BSM (n = 79) delivered via the internet. The Health Anxiety Inventory (HAI) was the primary outcome.
Results
Internet-delivered exposure-based CBT led to a significantly greater improvement on the HAI compared with BSM. However, both treatment groups made large improvements on the HAI (pre-to-post-treatment Cohen's d: exposure-based CBT, 1.78; BSM, 1.22).
Conclusions
Exposure-based CBT delivered via the internet is an efficacious treatment for severe health anxiety.