Multi-year passive acoustic monitoring of coastal dolphins along the Israeli Mediterranean shallow shelf reveals the impact of marine fish farms and trawling patterns on their habitat utilization.

Dolphin preference and usage of various habitats along the Israeli shallow coastal shelf were investigated between 2019 and 2021 with passive acoustic monitoring devices. A hurdle model was used to examine the dolphins' visiting probability (chance of detection) and visit duration (length of stay once detected) across habitats, with diel cycle and season as explanatory variables. The influence of spatiotemporal prohibitions placed on trawler activity was also examined. It was found that dolphins exhibited higher presence in the vicinity of fish farms, up to three orders of magnitude, and even more so during periods when trawler activity was halted. The study also found a higher presence during the winter season and nighttime. Modeling did not find significant differences in the visiting probability or the visit duration between any non-farm-associated sites, including areas where trawling is prohibited. Further restrictions on the fishing industry may induce recovery of the benthic ecosystem and lower competition for resources, thus promoting higher dolphin presence in natural habitats along the shelf.

Gender differences in risk attitudes.

PURPOSE: A rich literature has documented gender-based differences in health care utilization and outcomes. The role of risk attitude in explaining the variations is limited at best. This study examines gender differences in health utilities and risk attitudes. METHODOLOGY: Data on 13 health states were collected from 629 students via questionnaires at the Ben-Gurion University of the Negev in 2005. From each respondent, we assessed utilities for a subset of health states, using Time Trade-Off and Standard Gamble. A risk attitude coefficient was calculated for each respondent as a function of their utilities for all outcomes assessed. The risk coefficient derived from a closed-form utility model for men was compared to that of women using the t-statistic. FINDINGS: There was a statistically significant difference in the risk attitudes of men and women. Men had a concave utility function, representing risk aversion, while women had a near linear utility function, suggesting that women are risk neutral. PRACTICAL/SOCIAL IMPLICATIONS: Differences in risk attitude may be an important contributor to gender-based disparities in health services utilization. More research is needed to assess its full impact on decision-making in health care.

OAK-based cochleates as a novel approach to overcome multidrug resistance in bacteria.

Antibiotic resistance has become a worldwide medical problem. To find new ways of overcoming this phenomenon, we investigated the role of the membrane-active oligo-acyl-lysyl (OAK) sequence C(12)K-7α(8), in combination with essentially ineffective antibiotics. Determination of minimal inhibitory concentration (MIC) against gram-negative multidrug-resistant strains of Escherichia coli revealed combinations with sub-MIC OAK levels that acted synergistically with several antibiotics, thus lowering their MICs by several orders of magnitude. To shed light into the molecular basis for this synergism, we used both mutant strains and biochemical assays. Our results suggest that bacterial sensitization to antibiotics was derived mainly from the OAK's capacity to overcome the efflux-enhanced resistance mechanism, by promoting backdoor entry of otherwise excluded antibiotics. To facilitate simultaneous delivery of the pooled drugs to an infection site, we developed a novel OAK-based cochleate system with demonstrable stability in whole blood. To assess the potential therapeutic use of such cochleates, we performed preliminary experiments that imitate systemic treatment of neutropenic mice infected with lethal inoculums of multidrug resistance E. coli. Single-dose administration of erythromycin coencapsulated in OAK-based cochleates has decreased drug toxicity and increased therapeutic efficacy in a dose-dependent manner. Collectively, our findings suggest a potentially useful approach for fighting efflux-enhanced resistance mechanisms.