Report on the radiometric analysis of the Ghar Dalam fossil specimens prepared for the Ghar Dalam Museum

Uranium is a radioactive element emitting mainly alpha rays, but its daughter elements Th and Ra are gamma ray emitters. A high resolution gamma ray spectrometry system can be used to determine gamma-emitting radionuclides with energies ranging from 1 keV to 10 MeV depending on the type of detector in a large variety of sample matrices. The simultaneous detection of several gamma radionuclide emitters in the sample material was carried out with a coaxial germanium detector of high resolution connected to a multichannel analyser. Automatic processing of the collected spectral data was controlled by a computer system with selected software. Sources of error in the technique may be caused by improper spectral identities, changes in background, errors in calibration and/or geometry, and lack of homogeneity in samples. Since the samples tested were not in a standardised geometry, some variation in the readings could be expected due to the difference in sample homogeneity. The results obtained for the various samples were standardised as a ratio of 40K, on the assumption that the high solubility of potassium salts would result in a steady equilibrium in all samples. Several fossil specimens kept in the Ghar Dalam Museum were borrowed by courtesy of Dr. G. Zammit Maempel. The specimens had unfortunately no information as to the level they were excavated from, and their providence could not be reliably confirmed.peer-reviewe

Acute stress enhances heterodimerization and binding of corticosteroid receptors at glucocorticoid target genes in the hippocampus

A stressful event results in secretion of glucocorticoid hormones, which bind to mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) in the hippocampus to regulate cognitive and affective responses to the challenge. MRs are already highly occupied by low glucocorticoid levels under baseline conditions, whereas GRs only become substantially occupied by stress- or circadian-driven glucocorticoid levels. Currently, however, the binding of MRs and GRs to glucocorticoid-responsive elements (GREs) within hippocampal glucocorticoid target genes under such physiological conditions in vivo is unknown. We found that forced swim (FS) stress evoked increased hippocampal RNA expression levels of the glucocorticoid-responsive genes FK506-binding protein 5 (Fkbp5), Period 1 (Per1), and serum- and glucocorticoid-inducible kinase 1 (Sgk1). Chromatin immunoprecipitation (ChIP) analysis showed that this stressor caused substantial gene-dependent increases in GR binding and surprisingly, also MR binding to GREs within these genes. Different acute challenges, including novelty, restraint, and FS stress, produced distinct glucocorticoid responses but resulted in largely similar MR and GR binding to GREs. Sequential and tandem ChIP analyses showed that, after FS stress, MRs and GRs bind concomitantly to the same GRE sites within Fkbp5 and Per1 but not Sgk1. Thus, after stress, MRs and GRs seem to bind to GREs as homo- and/or heterodimers in a gene-dependent manner. MR binding to GREs at baseline seems to be restricted, whereas after stress, GR binding may facilitate cobinding of MR. This study reveals that the interaction of MRs and GRs with GREs within the genome constitutes an additional level of complexity in hippocampal glucocorticoid action beyond expectancies based on ligand–receptor interactions

On the introduction of Paranthrene tabaniformis (Rottemburg, 1775) in Malta (Insecta : Lepidoptera : Sesiidae)

The introduction of Paranthrene tabaniformis (Rottemburg) in· the Maltese Islands, an insect that is mainly associated with poplar trees (Populus sp.), is documented. Brief information is provided on the moth family Sesiidae with particular reference to the biology of P. tabaniformis. A brief overview of Maltese Sesiidae is included; previous records of Bembecia scopigera (Scopoli) were found to be incorrect as this material is B. albanensis tunetana (Le Cerf).peer-reviewe

Distinct epigenetic and gene expression changes in rat hippocampal neurons after Morris water maze training

Gene transcription and translation in the hippocampus is of critical importance in hippocampus-dependent memory formation, including during Morris water maze (MWM) learning. Previous work using gene deletion models has shown that the immediate-early genes (IEGs) c-Fos, Egr-1 and Arc are crucial for such learning. Recently, we reported that induction of IEGs in sparse dentate gyrus neurons requires ERK MAPK signaling and downstream formation of a distinct epigenetic histone mark (i.e. phospho-acetylated histone H3). Until now, this signaling, epigenetic and gene transcriptional pathway has not been comprehensively studied in the MWM model. Therefore, we conducted a detailed study of the phosphorylation of ERK1/2 and serine10 in histone H3 (H3S10p) and induction of IEGs in the hippocampus of MWM trained rats and matched controls. MWM training evoked consecutive waves of ERK1/2 phosphorylation and H3S10 phosphorylation, as well as c-Fos, Egr-1 and Arc induction in sparse hippocampal neurons. The observed effects were most pronounced in the dentate gyrus. A positive correlation was found between the average latency to find the platform and the number of H3S10p-positive dentate gyrus neurons. Furthermore, chromatin immuno-precipitation (ChIP) revealed a significantly increased association of phospho-acetylated histone H3 (H3K9ac-S10p) with the gene promoters of c-Fos and Egr-1, but not Arc, after MWM exposure compared with controls. Surprisingly, however, we found very little difference between IEG responses (regarding both protein and mRNA) in MWM-trained rats compared with matched swim controls. We conclude that exposure to the water maze evokes ERK MAPK activation, distinct epigenetic changes and IEG induction predominantly in sparse dentate gyrus neurons. It appears, however, that a specific role for IEGs in the learning aspect of MWM training may become apparent in downstream AP-1- and Egr-1-regulated (second wave) genes and Arc-dependent effector mechanisms

Using antiepileptic drugs in children : recent developments and recommendations

Epilepsy is one of the most common neurological disorders, with approximately 45 per 100,000 children developing new-onset epilepsy every year. Children are a vulnerable population with unique health needs and a correct diagnosis and thus correct treatment of epilepsy in children, particularly a diagnosis of early onset epilepsy, is important in order to ensure better quality of life, neurodevelopmental outcomes, cognition, education, improved level of function and future employment. Therapy with antiepileptic drugs (AEDs) aims to minimize the frequency of epileptic seizures with minimal side effects. The first generation AEDs (such as phenytoin, carbamazepine and valproic acid) are still widely used, although they are associated with serious side effects and pharmacokinetic problems (narrow therapeutic indices, nonlinear kinetics, and drug-drug interactions due to enzyme inhibition and enzyme induction properties). The novel AEDs (such as lamotrigine, levetiracetam, rufinamide, and zonisamide) have expanded the treatment options of epilepsy, however they are also associated with severe pharmacokinetic shortcomings, especially for paediatric populations. This educational article will discuss how the correct use of these drugs can lead to improved quality of life measures. This paper also provides an overview of ongoing research on the use of population pharmacokinetics in addressing the challenges paediatric populations offer to drug and dose individualisation.peer-reviewe

Climate change education for universities: a conceptual framework from an international study

The role of universities in climate change education (CCE) is of great importance if the scientific, social, environmental and political challenges the world faces are to be met. Future leaders must make decisions from an informed position and the public will need to embed climate change mitigation tools into their work and private life. It is therefore essential to understand the range of CCE strategies being taken globally by Higher Education Institutions (HEIs) and to explore and analyse the ways that HEIs could better address this challenge. Consistent with this research need, this paper offers an analysis of the extent to which HEIs in 45 countries approach CCE and provides a conceptual framework for exploring how HEIs are embedding CCE into their curricula. In addition to the specialist approach (where students choose to study a degree to become experts in climate change adaptation and mitigation tools), the CCE framework developed identifies and highlights three other approaches HEIs can deploy to embed CCE: Piggybacking, mainstreaming and connecting (transdisciplinary). Using data gathered in an explorative international survey involving participants working across academic and senior management, this paper illustrates the different approaches taken and analyses practical examples of current CCE practice from across the world. Responses from 212 university staff from 45 countries indicated that CCE was highly variable – no clear pattern was identified at the country level, with CCE approaches varying significantly, even within individual HEIs. This plurality highlights the wide range of ideas and examples being shared and used by institutions in very different countries and contexts, and underlines the importance of the independence and autonomy of HEIs so that they can choose the right CCE approaches for them. To highlight the breadth and variety of approaches that were uncovered by our survey, the paper offers a range of examples illustrating how climate change education may be embedded in a higher education context, some of which could be replicated in HEIs across the world. The conceptualisation of CCE and the examples given in this paper are valuable for anyone who is thinking about strategies for embedding more climate education in the higher education curriculum

Investigative study on the angiotensin converting enzyme (ACE) inhibiting properties of the terpenoid extract of Crataegus monogyna using in silico models

Crataegus monogyna is mainly used in the treatment of cardiac and circulatory system disorders. In vitro and clinical studies are indicative of the fact that the hydroethanolic extract of C. monogyna has angiotensin converting enzyme (ACE) inhibitory activity. This study sought to support these claims through the use of in silico modelling techniques. Possible binding conformations for β-amyrin, oleanolic acid and ursolic acid were generated using captopril, as well as enalaprilat and lisinopril, as template ligands. The ligand binding affinity (LBA) of each was calculated and the best binding conformation of each triterpene was established. Results indicate that these naturally occuring terpenes possess in silico predicted ligand binding affinities that are superior to both the small molecule captopril and the larger molecules enalaprilat and lisinopril.peer-reviewe

The macrobenthic species of the infralittoral to circalittoral transition zone off the northeastern coast of Malta (Central Mediterranean)

The macrobenthic assemblages of the sedimentary bottoms off the northeastern coast of Malta were studied during the summer of 1993. Crab and dredge samples were collected from depths of 21-75tn from an area of approximately 48 km2 off Comino, Mellieha Bay and St. Paul's Bay. Below ctr. 40m the bottorn was predominantly sandy with meadows of Posidonia oceanica, giving way to bare sand it1 the lower infralittoral. Between 45rn and 75r11, the bottom consisted of organogenic gravel with abundunt free-living culcureous rhodophytes, predominantly the corallines Phymatolithon calcareum and Lithothamnion corallioides. Such bot~oms, known as maerl, have not been reported previously from the Maltese Islands. 19 species of macroalgae, I phanerogam, and 108 species of macrofaunu were recorded, the bulk of these from the maerl bottom. An additional 122 species of molluscs occurred as etnpty shells. Maerl bottoms support a high species richness, even if abundance is low. There is evidence to suggest that maerl is the predominant bottom type all along the northeastern coast of the Maltese Islands in the tramition between the lower infralittoral and the circalittoral, which occurs at depths of 45-75m.peer-reviewe

GOTHiC, a probabilistic model to resolve complex biases and to identify real interactions in Hi-C data.

Hi-C is one of the main methods for investigating spatial co-localisation of DNA in the nucleus. However, the raw sequencing data obtained from Hi-C experiments suffer from large biases and spurious contacts, making it difficult to identify true interactions. Existing methods use complex models to account for biases and do not provide a significance threshold for detecting interactions. Here we introduce a simple binomial probabilistic model that resolves complex biases and distinguishes between true and false interactions. The model corrects biases of known and unknown origin and yields a p-value for each interaction, providing a reliable threshold based on significance. We demonstrate this experimentally by testing the method against a random ligation dataset. Our method outperforms previous methods and provides a statistical framework for further data analysis, such as comparisons of Hi-C interactions between different conditions. GOTHiC is available as a BioConductor package (http://www.bioconductor.org/packages/release/bioc/html/GOTHiC.html)