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The large-number hypothesis conjectures that fundamental constants may vary. Accordingly, the space-time variation of fundamental constants has been an active subject of research for decades. Recently, using data obtained with large telescopes a phenomenological model in which the fine structure constant might vary spatially has been proposed. We test whether this hypothetical spatial variation of alpha, which follows a dipole law, is compatible with the data of distant thermonuclear supernovae. Unlike previous works, in our calculations we consider not only the variation of the luminosity distance when a varying alpha is adopted, but we also take into account the variation of the peak luminosity of Type Ia supernovae resulting from a variation of alpha. This is done using an empirical relation for the peak bolometric magnitude of thermonuclear supernovae that correctly reproduces the results of detailed numerical simulations. We find that there is no significant difference between the several phenomenological models studied here and the standard one, in which alpha does not vary spatially. We conclude that the present set of data of Type Ia supernovae is not able to distinguish the standard model from the dipole models, and thus cannot be used to discard nor to confirm the proposed spatial variation of alpha., Peer Reviewed, Postprint (published version)

In the rodent forebrain GABAergic neurons are generated from progenitor cells that express the transcription factors Dlx1 and Dlx2. The Rap-1 guanine nucleotide exchange factor, MR-GEF, is turned on by many of these developing GABAergic neurons. Expression of both Dlx1/2 and MR-GEF is retained in both adult mouse and human forebrain where, in human, decreased Dlx1 expression has been associated with psychosis. Using in situ hybridization studies we show that MR-GEF expression is significantly down-regulated in the forebrain of Dlx1/2 double mutant mice suggesting that MR-GEF and Dlx1/2 form part of a common signalling pathway during GABAergic neuronal development. We therefore compared MR-GEF expression by in situ hybridization in individuals with major psychiatric disorders (schizophrenia, bipolar disorder, major depression) and control individuals. We observed a significant positive correlation between layers II and IV of the dorso-lateral prefrontal cortex (DLPFC) in the percentage of MR-GEF expressing neurons in individuals with bipolar disorder, but not in individuals with schizophrenia, major depressive disorder or in controls. Since MR-GEF encodes a Rap1 GEF able to activate G-protein signalling, we suggest that changes in MR-GEF expression could potentially influence neurotransmission.

BACKGROUND: There are multiple models of mental illness that inform professional and lay understanding. Few studies have formally investigated psychiatrists' attitudes. We aimed to measure how a group of trainee psychiatrists understand familiar mental illnesses in terms of propositions drawn from different models. METHOD: We used a questionnaire study of a sample of trainees from South London and Maudsley National Health Service (NHS) Foundation Trust designed to assess attitudes across eight models of mental illness (e.g. biological, psychodynamic) and four psychiatric disorders. Methods for analysing repeated measures and a principal components analysis (PCA) were used. RESULTS: No one model was endorsed by all respondents. Model endorsement varied with disorder. Attitudes to schizophrenia were expressed with the greatest conviction across models. Overall, the 'biological' model was the most strongly endorsed. The first three components of the PCA (interpreted as dimensions around which psychiatrists, as a group, understand mental illness) accounted for 56% of the variance. Each main component was classified in terms of its distinctive combination of statements from different models: PC1 33% biological versus non-biological; PC2 12% 'eclectic' (combining biological, behavioural, cognitive and spiritual models); and PC3 10% psychodynamic versus sociological. CONCLUSIONS: Trainee psychiatrists are most committed to the biological model for schizophrenia, but in general are not exclusively committed to any one model. As a group, they organize their attitudes towards mental illness in terms of a biological/non-biological contrast, an 'eclectic' view and a psychodynamic/sociological contrast. Better understanding of how professional group membership influences attitudes may facilitate better multidisciplinary working.

Water is a critical natural resource. It is used for drinking water, agriculture, wetlands services, and the production of hydroelectric energy, amongst others. Croatian fresh-water resources are abundant - indeed they are among the richest in Europe. Therefore, water resources are not considered a limiting factor for development in Croatia. However, while there is no shortage of water per se for use in Croatia, problems do exist. - First, a large amount of pumped water is wasted, which leads to lost revenue of up to EUR 286 million (0.9% of GDP) per year and increased GHG emissions resulting from the additional use of electricity for pumping. - Second, farmers often face water shortages at certain critical times of the year’s growing season and, in general, the soil lacks moisture. Croatia uses a small fraction of the water resources available (about 1%). However, climate change may stress some of the systems that depend upon freshwater. This may be especially important in terms of wetlands services and hydroelectric generation. Wetlands services include nutrient and pollutant removal from water, providing habitat for biodiversity, providing timber and providing hunting areas. During 2000-2007, 50% of all Croatian electricity production was from hydropower. The Croatian energy sector is potentially vulnerable if climate change results in reduced river flows – which is likely given the predictions of climate models simulating a drier Croatia. Reductions in hydroelectric generating capacity would thus reduce the nation’s level of energy security. For example, in 2003 and 2007, droughts caused significant losses in production compared to the average. This resulted in increased costs for electricity production of perhaps EUR 39-46 million in 2003 and EUR 102-120 million in 2007. Future decreases in hydroelectric production due to reduced runoff and river flows may require lost production to be offset by domestic or imported electricity. Both of these options are more c

The impact from climate change on agriculture is expected to be significant because of the vulnerability of agriculture to climate conditions in general. Precipitation, temperature, weather extremes and evaporation rates all impact production. Agriculture is important to the economy of Croatia due to its overall value and its impact on food security, vulnerable populations, and the employment it generates. In 2001, 92% of Croatia was classified as rural and 48% of the Croatian population lived in rural areas. Generally, rural households are more vulnerable due to poorer access to basic infrastructure and poorer housing conditions than households in urban areas. Existing climate variability already has a significant impact on agriculture. Extreme weather events have resulted in average losses of EUR 176 million per year during 2000-2007. This represents 0.6% of national GDP, or 9.3% of the GVA generated by the agricultural, forestry and fisheries sector. Looking at the future effect on maize alone, the lost revenue due to climate change would be EUR 6-16 million in 2050 and EUR 31-43 million in 2100. This corresponds to 0.8-5.7% of all revenue from arable crop sales in Croatia in 2005. Most of this damage is due to water shortage during critical times, as well as flooding and hail-storms which also cause damage. Particular years, such as 2003 and 2007, suffered huge economic damage that is difficult to recover. While some Government-supported insurance programmes and a new irrigation programme exist, current vulnerability to climate variability remains – particularly related to drought. However, little information is available to assess the consequences of farm practices and climate variables. There are few crop models or agricultural sector economic models that would help the sector understand current levels of vulnerability or future levels due to climate change. Furthermore, basic economic information about the sector and about the gross margins of crops is not av

In order to avoid dangerous climate change resulting from an increase in temperature of over 2oC, global GHG emissions must be cut by 50-85% by 2050. Croatia’s trajectory for emissions growth in the Business as Usual (BAU) case is estimated to result in 42 million tonnes of CO2e in 2020 – a significant increase from today. The EU has committed to reducing emissions by 20% by 2020. Croatia has committed to reducing emissions by an average of 5% for the period 2008-2012 from a baseline level of 36 million tonnes under the Kyoto Protocol. Croatia will also share at least part of the EU commitment for 2020, especially with respect to emissions from major point sources such as power plants and industrial sources. The energy sector is the largest source of GHG emissions in Croatia (73% in 2006). There are many potential measures to reduce emissions from the energy sector by 2020. It is estimated that by implementing the measures in the Energy Efficiency Master Plan, 1% of the national GDP could be saved. Emission reductions from households and the service industry could amount to almost 2 million tonnes by 2020 with a net economic benefit from energy cost savings. Industrial efficiency measures could also have a positive financial impact on companies. Producing electricity from renewable resources, increasing the efficiency of conversion and transmission, and – more controversially – moving to more nuclear power and electricity generated from burning waste, could yield significantly fewer emissions. Reducing fuel consumption in transportation through fuel-efficient vehicles, lower-carbon fuels, using biodiesel or other biofuels, or reducing car travel through better urban planning, public transportation, and traffic systems are also potential areas where emissions can be cut. The agricultural sector accounts for almost 11% of Croatian emission (2006). Agriculture can play a role in reducing direct emissions from agricultural soils and improved livestock and manure managem

BACKGROUND: Tricyclic antidepressants and serotonin reuptake inhibitors are considered to be equally effective, but differences may have been obscured by internally inconsistent measurement scales and inefficient statistical analyses. AIMS: To test the hypothesis that escitalopram and nortriptyline differ in their effects on observed mood, cognitive and neurovegetative symptoms of depression. METHOD: In a multicentre part-randomised open-label design (the Genome Based Therapeutic Drugs for Depression (GENDEP) study) 811 adults with moderate to severe unipolar depression were allocated to flexible dosage escitalopram or nortriptyline for 12 weeks. The weekly Montgomery-Asberg Depression Rating Scale, Hamilton Rating Scale for Depression, and Beck Depression Inventory were scored both conventionally and in a more novel way according to dimensions of observed mood, cognitive symptoms and neurovegetative symptoms. RESULTS: Mixed-effect linear regression showed no difference between escitalopram and nortriptyline on the three original scales, but symptom dimensions revealed drug-specific advantages. Observed mood and cognitive symptoms improved more with escitalopram than with nortriptyline. Neurovegetative symptoms improved more with nortriptyline than with escitalopram. CONCLUSIONS: The three symptom dimensions provided sensitive descriptors of differential antidepressant response and enabled identification of drug-specific effects.