Preventing yellow fever epidemics in Asian megacities: how can cities control mosquito-transmitted diseases?

The COVID-19 pandemic has reminded us of the ever present threat from infectious diseases, this includes the ones we know about already and future unknowns. The mosquito-transmitted disease yellow fever has claimed thousands of lives over the centuries and it hasn’t gone away. It is still endemic in tropical areas of Africa and Latin America, where it is kept at bay through constant surveillance, mass vaccination campaigns and some natural immunity within local populations. Despite this there are serious outbreaks from time to time. The Aedes mosquitoes capable of transmitting the virus from person to person, are now widespread in warmer countries worldwide, moreover they thrive in urban areas. With increased international movement, the fear is that infected travellers could unwittingly introduce the virus into countries where people have little or no immunity. Densely populated Asian megacities are a major concern. There are simple measures citizens can take to protect themselves and their homes from the bite of infected mosquitoes, but city leaders must be at the forefront of a coordinated response bringing together diverse stakeholders to ensure a robust and sustainable defence

Community between Europe and Africa

'Die Studie untersucht den Typ von Gemeinschaft, der durch die verschiedenen Lome Konventionen etabliert wurde. Die Beziehung zwischen der EG/ EU und den AKP-Staaten ist einem tiefgreifenden Wandel unterworfen. Während am Anfang die Beziehung auf der (kontrafaktischen) Unterstellung der Gleichheit der Vertragspartner und fairem Austausch basierte, wurde das Ungleichgewicht zwischen den Partnern im weiteren Verlauf immer offensichtlicher. Wurden die AKP-Staaten anfänglich als Klienten betrachtet, so wurden sie immer mehr zu Bittstellern, weil sich die sozio-ökonomischen und politischen Grundlagen veränderten, auf der die Fiktion der Gleichheit basierte. Das spezielle, als 'post-kolonial' charakterisierte Verhältnis zwischen der EG/ EU und den AKP-Staaten geht aller Wahrscheinlichkeit seinem Ende entgegen, genau so wie die besondere Form der Gemeinschaft, die sich zwischen diesen Staatengruppen entwickelt hatte. Auch in der Vergangenheit war das Verhältnis durch politische und ökonomische Konditionalität gekennzeichnet, die auf interne politische Reformen, Konfliktprävention und Armutsbekämpfung ausgerichtet war. So lange die EG/ EU nicht bereit und willens ist, direkt in diesen Staaten zu intervenieren, wird sie weiterhin die Entwicklungshilfe als indirektes Mittel benützen, um ihren politischen Interessen Geltung zu verschaffen. Dazu zählen neuerdings die Flüchtlingsproblematik, der Kampf gegen die Verbreitung von epidemischen Seuchen und der Kampf gegen den wachsenden Drogenhandel.' (Autorenreferat)'The study analyses the kind of community which was established through the various Lome Conventions. The relationship between the EC/ EU and the ACP countries has undergone profound changes. While in the beginning the relationship was based on the (contrafactual) supposition of equality between the partners and fair exchange the situation turned into a more openly unbalanced one. The real status of the ACP countries turned from client to supplicant because the socio-economic and political rational for upholding the fiction of equality vanished. The special 'post-colonial' relationship between the EC/ EU and the ACP countries is likely to come to an end as is the particular form of community between these two groups of states. Even in the past the relationship was characterised by political and economic conditionality aimed at internal political reform, conflict prevention, and poverty alleviation. Nevertheless, as long as the EC/ EU is not ready and willing to directly intervene in these countries it will rely on development aid as an indirect means to address its political concerns which now include refugee flight, the spread of cross border epidemic disease, and the growth of narcotics trade.' (author's abstract)

Community in Europe: a historical lexicon

Eines der Hauptargumente für die EU ist die anhaltende hohe Arbeitslosigkeit in allen Ländern der Union. Das vorliegende Arbeitspapier zeigt, dass die EU bei Bekämpfung der Arbeitslosigkeit sich in fast allen ihren Statements und Forderungen zwischen mehr Wettbewerbsfähigkeit auf den Märkten einerseits und 'sozialem Schutz', 'sozialer Balance' und 'sozialer Verantwortung' andererseits bewegt. Die schwierige Frage ist dabei die nach der Vereinbarkeit zwischen individueller Eigenverantwortlichkeit und staatlichen Interventionen und Regulierungen, die häufig mit den Freiheitsrechten des Einzelnen in Konflikt geraten. Die Kollision zwischen Selbständigkeit und dem Anspruch auf wohlfahrtsstaatliche Hilfe ist nur zu lösen, wenn der Verlust an subsidiären Solidarleistungen durch eine sozial vertretbare Form der kollektiven Hilfeleistungen kompensiert werden kann. (ICAÜbers)'One of the main causes of flagging support for the EU has been the persistence of high levels of unemployment in virtually all member states of the Union. Our paper shows that in combating unemployment, present policy as set out in EU documents is forced to steer a course between 'competitiveness' of markets and what is variously referred to as 'social protection', 'social balance' or 'social responsibility'. The difficult question which then arises is how an injunction for individual responsibility can be enforced through rules and regulations which run against the principle of freedom to which responsibility is attached. When freedom is associated with social custom or convention, and that it is customary for individuals to have a state-provided social benefit, a 'community' of social responsibility and the like becomes so problematic. The task is finding the means of persuasion that makes the loss of local custom and individual dependence appear as a socially responsible but private gain of livelihood.' (author's abstract)

Stochastic models in population biology and their deterministic analogs

In this paper we introduce a class of stochastic population models based on "patch dynamics". The size of the patch may be varied, and this allows one to quantify the departures of these stochastic models from various mean field theories, which are generally valid as the patch size becomes very large. These models may be used to formulate a broad range of biological processes in both spatial and non-spatial contexts. Here, we concentrate on two-species competition. We present both a mathematical analysis of the patch model, in which we derive the precise form of the competition mean field equations (and their first order corrections in the non-spatial case), and simulation results. These mean field equations differ, in some important ways, from those which are normally written down on phenomenological grounds. Our general conclusion is that mean field theory is more robust for spatial models than for a single isolated patch. This is due to the dilution of stochastic effects in a spatial setting resulting from repeated rescue events mediated by inter-patch diffusion. However, discrete effects due to modest patch sizes lead to striking deviations from mean field theory even in a spatial setting.Comment: 47 pages, 9 figure

Thioredoxins function as deglutathionylase enzymes in the yeast Saccharomyces cerevisiae

<p>Abstract</p> <p>Background</p> <p>Protein-SH groups are amongst the most easily oxidized residues in proteins, but irreversible oxidation can be prevented by protein glutathionylation, in which protein-SH groups form mixed disulphides with glutathione. Glutaredoxins and thioredoxins are key oxidoreductases which have been implicated in regulating glutathionylation/deglutathionylation in diverse organisms. Glutaredoxins have been proposed to be the predominant deglutathionylase enzymes in many plant and mammalian species, whereas, thioredoxins have generally been thought to be relatively inefficient in deglutathionylation.</p> <p>Results</p> <p>We show here that the levels of glutathionylated proteins in yeast are regulated in parallel with the growth cycle, and are maximal during stationary phase growth. This increase in glutathionylation is not a response to increased reactive oxygen species generated from the shift to respiratory metabolism, but appears to be a general response to starvation conditions. Our data indicate that glutathionylation levels are constitutively high in all growth phases in thioredoxin mutants and are unaffected in glutaredoxin mutants. We have confirmed that thioredoxins, but not glutaredoxins, catalyse deglutathionylation of model glutathionylated substrates using purified thioredoxin and glutaredoxin proteins. Furthermore, we show that the deglutathionylase activity of thioredoxins is required to reduce the high levels of glutathionylation in stationary phase cells, which occurs as cells exit stationary phase and resume vegetative growth.</p> <p>Conclusions</p> <p>There is increasing evidence that the thioredoxin and glutathione redox systems have overlapping functions and these present data indicate that the thioredoxin system plays a key role in regulating the modification of proteins by the glutathione system.</p

Left auditory cortex gamma synchronization and auditory hallucination symptoms in schizophrenia

<p>Abstract</p> <p>Background</p> <p>Oscillatory electroencephalogram (EEG) abnormalities may reflect neural circuit dysfunction in neuropsychiatric disorders. Previously we have found positive correlations between the phase synchronization of beta and gamma oscillations and hallucination symptoms in schizophrenia patients. These findings suggest that the propensity for hallucinations is associated with an increased tendency for neural circuits in sensory cortex to enter states of oscillatory synchrony. Here we tested this hypothesis by examining whether the 40 Hz auditory steady-state response (ASSR) generated in the left primary auditory cortex is positively correlated with auditory hallucination symptoms in schizophrenia. We also examined whether the 40 Hz ASSR deficit in schizophrenia was associated with cross-frequency interactions.</p> <p>Sixteen healthy control subjects (HC) and 18 chronic schizophrenia patients (SZ) listened to 40 Hz binaural click trains. The EEG was recorded from 60 electrodes and average-referenced offline. A 5-dipole model was fit from the HC grand average ASSR, with 2 pairs of superior temporal dipoles and a deep midline dipole. Time-frequency decomposition was performed on the scalp EEG and source data.</p> <p>Results</p> <p>Phase locking factor (PLF) and evoked power were reduced in SZ at fronto-central electrodes, replicating prior findings. PLF was reduced in SZ for non-homologous right and left hemisphere sources. Left hemisphere source PLF in SZ was positively correlated with auditory hallucination symptoms, and was modulated by delta phase. Furthermore, the correlations between source evoked power and PLF found in HC was reduced in SZ for the LH sources.</p> <p>Conclusion</p> <p>These findings suggest that differential neural circuit abnormalities may be present in the left and right auditory cortices in schizophrenia. In addition, they provide further support for the hypothesis that hallucinations are related to cortical hyperexcitability, which is manifested by an increased propensity for high-frequency synchronization in modality-specific cortical areas.</p

Detection and analysis of statistical differences in anatomical shape

We present a computational framework for image-based analysis and interpretation of statistical differences in anatomical shape between populations. Applications of such analysis include understanding developmental and anatomical aspects of disorders when comparing patients vs. normal controls, studying morphological changes caused by aging, or even differences in normal anatomy, for example, differences between genders. Once a quantitative description of organ shape is extracted from input images, the problem of identifying differences between the two groups can be reduced to one of the classical questions in machine learning of constructing a classifier function for assigning new examples to one of the two groups while making as few misclassifications as possible. The resulting classifier must be interpreted in terms of shape differences between the two groups back in the image domain. We demonstrate a novel approach to such interpretation that allows us to argue about the identified shape differences in anatomically meaningful terms of organ deformation. Given a classifier function in the feature space, we derive a deformation that corresponds to the differences between the two classes while ignoring shape variability within each class. Based on this approach, we present a system for statistical shape analysis using distance transforms for shape representation and the Support Vector Machines learning algorithm for the optimal classifier estimation and demonstrate it on artificially generated data sets, as well as real medical studies