Recent advances in malaria genomics and epigenomics

Malaria continues to impose a significant disease burden on low- and middle-income countries in the tropics. However, revolutionary progress over the last 3 years in nucleic acid sequencing, reverse genetics, and post-genome analyses has generated step changes in our understanding of malaria parasite (Plasmodium spp.) biology and its interactions with its host and vector. Driven by the availability of vast amounts of genome sequence data from Plasmodium species strains, relevant human populations of different ethnicities, and mosquito vectors, researchers can consider any biological component of the malarial process in isolation or in the interactive setting that is infection. In particular, considerable progress has been made in the area of population genomics, with Plasmodium falciparum serving as a highly relevant model. Such studies have demonstrated that genome evolution under strong selective pressure can be detected. These data, combined with reverse genetics, have enabled the identification of the region of the P. falciparum genome that is under selective pressure and the confirmation of the functionality of the mutations in the kelch13 gene that accompany resistance to the major frontline antimalarial, artemisinin. Furthermore, the central role of epigenetic regulation of gene expression and antigenic variation and developmental fate in P. falciparum is becoming ever clearer. This review summarizes recent exciting discoveries that genome technologies have enabled in malaria research and highlights some of their applications to healthcare. The knowledge gained will help to develop surveillance approaches for the emergence or spread of drug resistance and to identify new targets for the development of antimalarial drugs and perhaps vaccines

Brazilian WHOQOL-OLD module version: a Rasch analysis of a new instrument

OBJECTIVE: To evaluate the Brazilian version of WHOQOL-OLD Module and to test potential changes to the instrument to increase its psychometric adequacy. METHODS: A total of 424 older adults living in a city in Southern Brazil completed the WHOQOL-OLD instrument, in 2005. Rasch analysis was used to explore the psychometric performance of the scale, as implemented by the RUMM2020 software. Item-trait interaction, threshold disorders, presence of differential item functioning and item fit, were analyzed. RESULTS: Two ("death and dying" and "sensory abilities") out of six domains showed inadequate item-trait interactions. Rescoring the response scale and deleting the most misperforming items led to scale improvement. The evaluation of domains and items individually showed that the "intimacy" domain does perform well in contrast to the findings using the classical approach. In addition, the "sensory abilities" domain does not derive an interval measure in its current format. CONCLUSIONS: Unidimensionality and local independence were seen in all domains. Changes in the response scale and deletion of problematic items improved the scale's performance

Using the HEXACO to Capture Psychopathy: Development and Initial Validation of the Power Proxies of Psychopathic Traits

Psychopathy, though often considered an abnormal personality construct, has been repeatedly found to be related to “normal” personality traits, and the HEXACO model of personality is particularly capable of capturing the “dark” personality variance integral to the construct. Additionally, while previous research indicates that psychopathy can be applied to both sexes, it has been suggested that psychopathic traits are expressed somewhat differently between men and women. In Study 1, we examined the relations between the Self-Report Psychopathy Scale (SRP) and the HEXACO-60 in a student sample (n = 1,346) in order to create proxy measures for Hare’s two-factor/four-facet model of psychopathy and to investigate sex differences in the associations between the SRP and the HEXACO. We created “general” proxies for use with samples of men and women in addition to male- and female-specific proxies for potential use with samples of exclusively men or women, respectively. The proxies had good psychometric properties and had stronger correlations with several psychopathy-relevant variables than did a previous attempt to measure the SRP facets using HEXACO items. In Study 2, we investigated how the proxies would function in a youth community sample (n = 396). The proxies related to many external variables in a similar manner as that of a previously validated measure of psychopathic traits in youth, suggesting that the proxy scales can be used with younger populations. In Study 3, we used a MTurk sample (n = 471) to update the proxy scales with HEXACO-100 items and to investigate sex differences in the relations between the SRP and the new HEXACO items. Several items were added to each version of the proxy scales and, compared to the original proxies, the updated proxies displayed better psychometric properties and stronger correlations with psychopathy-relevant variables. Overall, this program of research demonstrates considerable overlap between Hare’s model of psychopathy and the HEXACO model of personality. Honesty-Humility and altruism seem to underlie all of the psychopathy scales, whereas aspects of the other HEXACO domains tend to differentiate the psychopathy scales from one another. Further, several sex differences in how psychopathic traits relate to basic personality were identified

Fresh Water to Arabia by VLCC-Fact or Folly?

Population growth, industrial development and the esoteric goals of national self-sufficiency in water and food propels the arid nations of Arabia in a voracious scavenge for alternative resources of fresh water as depletion and contamination of the natural aquifers have reached critical proportions. Desalination of sea water is currently the preferred alternative source of fresh water. Recent misgivings concerning the antroprogenic discharge of desalination effluent (i.e. high temperature and high saline water) into the semi-enclosed, epicontinental waters of the Arabian Gulf question the sustainability of this process. Demonstrable deleterious affects of such a process on the marine ecosystem of the Gulf imparts new impetus into the concept of fresh water backhaul by VLCC, a practical alternative source of fresh water. Although suggested over a decade ago, this maritime option was never pursued. Recent innovations in VLCC design and the legislative environment in which it operates indicate that conventional VLCCs substantially augment the prospects of such a proposal. By eliciting and combining the deleterious affects of desalination and the virtues of the modern VLCC, this paper attempts to justify the commercial and sustainable viability of the VLCC backhaul of European fresh water to the Middle East