Droplet impact onto moving liquids

From rain drops landing on the ocean to inkjet printing, the impact of droplets onto moving liquid surfaces is a ubiquitous process in nature and in industry. A rich range of phenomena can arise. The behaviour depends on the inertia, the properties of the drops and the relative speeds in the impact zone. While the result ranges from tranquil coalescence to violent splashing, intermediate regimes also occur, including partial and complete bouncing and even 'surfing' of the droplet. These regimes are determined by the ratio of the drop and surface velocities and the liquid properties. A regime diagram can be constructed in which distinct dynamical regimes are clearly identified.This project was supported by the EPSRC (grant EP/H018913/1), the John Fell Oxford University Press Research Fund, and the Royal Society (through a University Research Fellowship and a Research Grant)

Manufacturing process of a brain aneurysm biomodel in PDMS using rapid prototyping

Cerebral aneurysm is an abnormal dilatation of the blood vessel into a saccular form. They can originate in congenital defects, weakening of the arterial wall with increasing age, atherosclerotic changes, trauma and infectious emboli. The in vivo experiments are an effective way of investigating the appearance, validating new practices and techniques, but beyond ethical issues, these types of experiments are expensive and have low reproducibility. Thus, to better understand the pathophysiological and geometric aspects of an aneurysm, it is important to fabricate in vitro models capable of improving existing endovascular treatments, developing and validating theoretical and computational models. Another difficulty is in the preoperative period of the non-ruptured cerebral aneurysm, known for the success of the skilled acts because there is an anatomical structure of the aneurysm as its current position. Although there are technologies that facilitate three-dimensional video visualization in the case of aneurysms with complex geometries the operative planning is still complicated, so the development of the real three-dimensional physical model becomes advantageous. In this work, the entire process of manufacturing an aneurysm biomodel using polydimethylsiloxane (PDMS) is disassembled by rapid prototyping technology. The manufactured biomodels are able to perform different hemodynamic studies, validate theoretical data, numerical simulations and assist in the preoperative planning.info:eu-repo/semantics/publishedVersio

Strategic approaches to restoring ecosystems can triple conservation gains and halve costs.

International commitments for ecosystem restoration add up to one-quarter of the world's arable land. Fulfilling them would ease global challenges such as climate change and biodiversity decline but could displace food production and impose financial costs on farmers. Here, we present a restoration prioritization approach capable of revealing these synergies and trade-offs, incorporating ecological and economic efficiencies of scale and modelling specific policy options. Using an actual large-scale restoration target of the Atlantic Forest hotspot, we show that our approach can deliver an eightfold increase in cost-effectiveness for biodiversity conservation compared with a baseline of non-systematic restoration. A compromise solution avoids 26% of the biome's current extinction debt of 2,864 plant and animal species (an increase of 257% compared with the baseline). Moreover, this solution sequesters 1 billion tonnes of CO2-equivalent (a 105% increase) while reducing costs by US$28 billion (a 57% decrease). Seizing similar opportunities elsewhere would offer substantial contributions to some of the greatest challenges for humankind

HIF-1 and c-Src Mediate Increased Glucose Uptake Induced by Endothelin-1 and Connexin43 in Astrocytes

In previous work we showed that endothelin-1 (ET-1) increases the rate of glucose uptake in astrocytes, an important aspect of brain function since glucose taken up by astrocytes is used to supply the neurons with metabolic substrates. In the present work we sought to identify the signalling pathway responsible for this process in primary culture of rat astrocytes. Our results show that ET-1 promoted an increase in the transcription factor hypoxia-inducible factor-1α (HIF-1α) in astrocytes, as shown in other cell types. Furthermore, HIF-1α-siRNA experiments revealed that HIF-1α participates in the effects of ET-1 on glucose uptake and on the expression of GLUT-1, GLUT-3, type I and type II hexokinase. We previously reported that these effects of ET-1 are mediated by connexin43 (Cx43), the major gap junction protein in astrocytes. Indeed, our results show that silencing Cx43 increased HIF-1α and reduced the effect of ET-1 on HIF-1α, indicating that the effect of ET-1 on HIF-1α is mediated by Cx43. The activity of oncogenes such as c-Src can up-regulate HIF-1α. Since Cx43 interacts with c-Src, we investigated the participation of c-Src in this pathway. Interestingly, both the treatment with ET-1 and with Cx43-siRNA increased c-Src activity. In addition, when c-Src activity was inhibited neither ET-1 nor silencing Cx43 were able to up-regulate HIF-1α. In conclusion, our results suggest that ET-1 by down-regulating Cx43 activates c-Src, which in turn increases HIF-1α leading to the up-regulation of the machinery required to take up glucose in astrocytes. Cx43 expression can be reduced in response not only to ET-1 but also to various physiological and pathological stimuli. This study contributes to the identification of the signalling pathway evoked after Cx43 down-regulation that results in increased glucose uptake in astrocytes. Interestingly, this is the first evidence linking Cx43 to HIF-1, which is a master regulator of glucose metabolism

The emotional movie database (EMDB): a self-report and psychophysiological study

Film clips are an important tool for evoking emotional responses in the laboratory. When compared with other emotionally potent visual stimuli (e.g., pictures), film clips seem to be more effective in eliciting emotions for longer periods of time at both the subjective and physiological levels. The main objective of the present study was to develop a new database of affective film clips without auditory content, based on a dimensional approach to emotional stimuli (valence, arousal and dominance). The study had three different phases: (1) the pre-selection and editing of 52 film clips (2) the self-report rating of these film clips by a sample of 113 participants and (3) psychophysiological assessment [skin conductance level (SCL) and the heart rate (HR)] on 32 volunteers. Film clips from different categories were selected to elicit emotional states from different quadrants of affective space. The results also showed that sustained exposure to the affective film clips resulted in a pattern of a SCL increase and HR deceleration in high arousal conditions (i.e., horror and erotic conditions). The resulting emotional movie database can reliably be used in research requiring the presentation of non-auditory film clips with different ratings of valence, arousal and dominance.Portuguese Foundation for Science and Technology with individual grants (SFRH/BD/41484/2007 and SFRH/BD/64355/2009

Suicidality in primary care patients who present with sadness and anhedonia: a prospective European study

Background: Sadness and anhedonia (loss of interest in activities) are central symptoms of major depression. However, not all people with these symptoms meet diagnostic criteria for major depression. We aimed to assess the importance of suicidality in the outcomes for primary care patients who present with sadness and anhedonia. Method: Cohort study of 2,599 unselected primary care attenders in six European countries followed up at 6 and 12 months. Results: 1) In patients with sadness and/or anhedonia who were not depressed at entry to the study, suicide plans (OR = 3.05; 95 % CI = 1.50–6.24; p = 0.0022) and suicide attempts (OR = 9.08; 95 % CI = 2.57–32.03; p = 0.0006) were significant predictors of developing new onset depression at 6 or 12 months. 2) In patients with sadness and/or anhedonia who met CIDI criteria for major depression at entry, suicidal ideation (OR = 2.93; 95 % CI = 1.70–5.07; p = 0.0001), suicide plans (OR = 3.70; 95 % CI = 2.08–6.57; p < 0.0001), and suicide attempts (OR = 3.33; 95 % CI = 1.47–7.54; p = 0.0040) were significant predictors of persistent depression at 6 or 12 months. Conclusions: Three questions on suicidality could help primary care professionals to assess such patients more closely without necessarily establishing whether they meet criteria for major depression.This research was funded by a grant from The European Commission, referencePREDICT-QL4-CT2002-00683. We are also grateful for part support in Europe from: the Estonian Scientific Foundation (grant number 5696); the Slovenian Ministry for Research (grant No.4369-1027); the Spanish Ministry of Health (grant FIS references: PI041980, PI041771, PI042450) and the Spanish Network of Primary Care Research, redIAPP (ISCIII-RETICS RD06/0018) and SAMSERAP group; and the UK NHS Research and Development office for providing service support costs in the UK. We are also grateful for the support from the University of Malaga (Spain) and to Carlos García from Loyola Andalucía University (Spain)