Anthropogenically-induced oil spills release large amounts of organic pollutants into the marine environment. To date, little is known about the response of microbial populations (biomass, activity ...and diversity) to crude oil pollution in Low Nutrients Low Chlorophyll and warm systems. Here, we investigated the daily dynamics of phytoplankton and heterotrophic bacteria in response to an oil spill (500 μm thick layer) in the coastal waters of the SE Mediterranean Sea (SEMS), using mesocosms during winter and summer. Crude oil addition caused a marked decrease in phytoplankton biomass (40–76%) and production rates (22–96%), whereas heterotrophic bacterial abundance and production increased (4–68% and 17–165%, respectively). Concurrently, amplicon sequencing of the 16S rRNA gene revealed that oil-degrading bacteria became abundant 48–96 h post-oil addition, while the cosmopolitan Synechococcus and SAR11 lineages were significantly reduced (by 78–98% and 59–98%, respectively). Fertilization with inorganic nutrients (NO3 and PO4) reduced the deleterious effects of the oil, resulting in a less distinct reduction in phytoplankton biomass/abundance. Our results highlight the potential of intrinsic microbial communities to degrade oil-derived pollutants in oligotrophic coastal waters.
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•Ramifications of oil spills were studied in the SE Mediterranean Sea coastal water.•Crude-oil addition resulted in decreased abundances of Synechococcus and SAR11.•Hydrocarbon degraders became abundant following crude oil amendment.•N+P addition reduced the inhibitory effects of oil pollution to phytoplankton.
Anthropogenically-induced oil spills release large amounts of organic pollutants into the marine environment. To date, little is known about the response of microbial populations (biomass, activity ...and diversity) to crude oil pollution in Low Nutrients Low Chlorophyll and warm systems. Here, I investigated the temporal daily dynamics of phytoplankton and heterotrophic bacteria in response to an oil spill (500 µm thick layer, representing a severe event) in the coastal water of the Southeastern Mediterranean Sea, and the corresponding oil degradation using mesocosms held during winter and summer. Crude oil addition usually caused a marked decrease in phytoplankton biomass (40-76%) and production rates (22-96%), whereas heterotrophic bacterial abundance and bacterial production increased (4-68% and 17-165%, respectively). The increased heterotrophic activity was coupled with elevated short-chain n-alkans and other oil derivates (49-1100% relative to the unamended controls), suggesting oil-degrading bacterial potential in the eastern Mediterranean coastal water. Concurrently, amplicon sequencing of the 16S rRNA gene revealed that oil-degrading bacteria became abundant 48-96 h post-oil addition, while the cosmopolitan Synechococcus and SAR11 lineages were significantly reduced (by 78-98% and 59-98%, respectively). Additional fertilization with inorganic nutrients (NO3 and PO4) reduced the deleterious effects of the crude oil, resulting in a less distinct reduction in phytoplankton biomass/abundance (~40-50%) and an increase oil derivates. My results highlight the potential of intrinsic microbial communities to degrade oil-derived pollutants in oligotrophic coastal water. To the best of my knowledge, this is the first time that such study was carried out in the Israeli water. Results from this study will enable decision makers (e.g., Ministry of Energy, Ministry of Environmental Protection) to apply a better science-based environmental policy in the case of marine oil pollution on the Israeli shore, specificly simulated of in situ remediation treatment with the addition of nutrients.
Studying the military and other security organizations is challenging for both methodological and ethical reasons. Studying these domains “at home,” literally in the researcher’s own country, ...complicates things even further. This article discusses these intricacies by proposing a dynamic conceptualization of the subject-object relationship in the study of the military and security in Israel. This conceptualization illuminates the effects of the dynamic positioning of the researcher in four social fields: the academic, the military-security, gender, and the ethno-national. The actual influence of these fields and their interrelations changes throughout the phases of research. We argue that when researchers and their respondents have similar ethno-national affiliation and military experiences, the dichotomous relations between them break down and give way to a dense web of expectations. This brings the researcher to maneuver between two, ostensibly contradictory, research strategies:
studying-up
and
studying-across
. The paper unpacks the complexities encapsulated in these strategies by discussing methodological and ethical dilemmas in two field studies on the Israeli-Palestinian conflict conducted by the authors.
In attempting to explain Israel's retaliatory policies toward Palestinian violence, new institutionalist and rational choice theories vie for dominance. This article argues that both approaches can ...contribute to understanding the severity of Israel's response if they are viewed as nested explanations appropriate to different threat levels. The article makes its case using data from 74 interviews with senior Israeli counterterrorist experts (2006-07), counts of Israeli and Palestinian fatalities due to state and collective violence (1987-2007), and a database of collective violence events during the Second Intifada (2000-05). Institutional effects are evident at low threat levels, as new institutionalists predict, but these effects are overwhelmed at high threat levels, as rational choice theorists assert.
Immune responses generally decline with age. However, the dynamics of this process at the individual level have not been characterized, hindering quantification of an individual's immune age. Here, ...we use multiple 'omics' technologies to capture population- and individual-level changes in the human immune system of 135 healthy adult individuals of different ages sampled longitudinally over a nine-year period. We observed high inter-individual variability in the rates of change of cellular frequencies that was dictated by their baseline values, allowing identification of steady-state levels toward which a cell subset converged and the ordered convergence of multiple cell subsets toward an older adult homeostasis. These data form a high-dimensional trajectory of immune aging (IMM-AGE) that describes a person's immune status better than chronological age. We show that the IMM-AGE score predicted all-cause mortality beyond well-established risk factors in the Framingham Heart Study, establishing its potential use in clinics for identification of patients at risk.
Crowdfunding campaigns, where entrepreneurs seek consumer funding to develop new products, foster dynamics that go beyond traditional seller–buyer transactions. This research studies how consumers ...increase their participation when they believe their contribution is pivotal to product creation. Utilizing controlled experiments we find that making-the-product-happen motivates participation above and beyond the desire to help the entrepreneurs. Moreover, we show how this motivation, which increases when an all-or-nothing campaign is drawing to a close and its financing target is within reach, is driven by future product availability. Furthermore, we identify conditions where making-it-happen dominates herding and an increase in the backing actions of others decreases one's willingness to back. Lastly, consistent with the notion that individual backers can determine campaign success, an analysis of over 200,000 Kickstarter projects shows that 33% of all successful campaigns hinge on the marginal support of no more than three average backers.
•Crowdfunding engages consumers for financing of yet to be developed products.•We examine the effect of pivotal consideration in such a crowdfunding context.•We identify a novel “making-the-product-happen” crowdfunding motivation.•This motivation is driven by future product availability and may dominate herding.•Identifying such motivations carry implications for platforms and entrepreneurs.
Contemporary understanding of combat trauma’s psychological effects emphasizes the interpersonal ways survivors process their experiences. Yet cases of incongruence between survivors who want to ...share their traumatic experience and close others who are not ready to take part in this challenging task are common. Hence, many trauma survivors are compelled to cope with the posttraumatic consequences mostly alone. The present study followed the interpretive phenomenological approach to examine the experience of loneliness, as described by 15 male combat veterans dealing with posttraumatic stress. Participants completed semistructured qualitative interviews in which they shared their knowledge regarding postservice distress, loneliness, coping, and growth. Two main themes emerged: “The Loneliness Complex,” highlighting this phenomenon’s multifaceted, layered, and cyclical nature; and “Emotional Growth after Loneliness,” presenting the positive potential of loneliness. These findings emphasize the importance of interpersonal relations in trauma survivors’ recovery process. Participants described how experiences with peers can serve as a pivotal point for coping with postservice distress and how internalization of positive interpersonal interactions seems to be a crucial psychological resource for further rehabilitation and growth. Being a multilayered and cyclical condition, loneliness might serve trauma survivors in their search of safety, while also bearing the potential to motivate them to act upon their condition and promote emotional growth. Clinicians should acknowledge the risks trauma survivors take by leaving their lonely yet safe place, as they are encouraged to process their traumatic experiences and share their inner world with others.
Abstract
Hybrid photonic structures of plasmonic metasurfaces coupled to atomically thin semiconductors have emerged as a versatile platform for strong light–matter interaction, supporting both ...strong coupling and parametric nonlinearities. However, designing optimized nonlinear hybrid metasurfaces is a complex task, as the multiple parameters’ contribution to the nonlinear response is elusive. Here we present a simple yet powerful strategy for maximizing the nonlinear response of the hybrid structures based on evolutionary inverse design of the metasurface’s near-field enhancement around the excitonic frequency. We show that the strong coupling greatly enhances the nonlinear signal, and that its magnitude is mainly determined by the Rabi splitting, making it robust to geometrical variations of the metasurface. Furthermore, the large Rabi splitting attained by these hybrid structures enables broadband operation over the frequencies of the hybridized modes. Our results constitute a significant step toward achieving flexible nonlinear control, which can benefit applications in nonlinear frequency conversion, all-optical switching, and phase-controlled nonlinear metasurfaces.
Despite much research, our understanding of the architecture and
-regulatory elements of human promoters is still lacking. Here, we devised a high-throughput assay to quantify the activity of ...approximately 15,000 fully designed sequences that we integrated and expressed from a fixed location within the human genome. We used this method to investigate thousands of native promoters and preinitiation complex (PIC) binding regions followed by in-depth characterization of the sequence motifs underlying promoter activity, including core promoter elements and TF binding sites. We find that core promoters drive transcription mostly unidirectionally and that sequences originating from promoters exhibit stronger activity than those originating from enhancers. By testing multiple synthetic configurations of core promoter elements, we dissect the motifs that positively and negatively regulate transcription as well as the effect of their combinations and distances, including a 10-bp periodicity in the optimal distance between the TATA and the initiator. By comprehensively screening 133 TF binding sites, we find that in contrast to core promoters, TF binding sites maintain similar activity levels in both orientations, supporting a model by which divergent transcription is driven by two distinct unidirectional core promoters sharing bidirectional TF binding sites. Finally, we find a striking agreement between the effect of binding site multiplicity of individual TFs in our assay and their tendency to appear in homotypic clusters throughout the genome. Overall, our study systematically assays the elements that drive expression in core and proximal promoter regions and sheds light on organization principles of regulatory regions in the human genome.
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