352 research outputs found
Persistent gender bias in marine science and conservation calls for action to achieve equity
The increasing consideration of gender balance in conservation science and practice has been reflected in the setting of global commitments. Yet, women remain under-represented in science and conservation decision-making. We compiled and analyzed data on the representation of women in hiring, publishing, funding, and leadership positions in European Union marine sciences and conservation. To explore scientists' perceptions of gender imbalance in marine sciences and conservation more broadly, we conducted a global survey and analyzed 764 questionnaires from 42 countries. Participants were also asked to identify measures that promote gender equity. We found a consistent pattern of women being under-representated across institutions and nations characterized by a relatively balanced representation of men and women in early career stages and a growing gap in later stages, with women occupying only 13% to 24% of senior positions. The same pattern was found in publishing, funding, and leadership of research institutes. Survey results demonstrate that most marine scientists are aware of the general and persistent gender bias, and perceive that it may compromise our ability to effectively solve conservation problems. Measures that increase fairness in evaluations (e.g. for hiring) and that support work-life balance ranked high, whereas gender-oriented measures, such as gender-specific scholarships, received less support. Our findings suggest that mechanisms promoting a fairer share of family responsibilities and transparent processes in hiring and evaluation are the most promising path to a more balanced participation of women in scientific leadership and conservation decision-making. Such measures may benefit not only women but diversity more generally
Embedding a Native State into a Random Heteropolymer Model: The Dynamic Approach
We study a random heteropolymer model with Langevin dynamics, in the
supersymmetric formulation. Employing a procedure similar to one that has been
used in static calculations, we construct an ensemble in which the affinity of
the system for a native state is controlled by a "selection temperature" T0. In
the limit of high T0, the model reduces to a random heteropolymer, while for
T0-->0 the system is forced into the native state. Within the Gaussian
variational approach that we employed previously for the random heteropolymer,
we explore the phases of the system for large and small T0. For large T0, the
system exhibits a (dynamical) spin glass phase, like that found for the random
heteropolymer, below a temperature Tg. For small T0, we find an ordered phase,
characterized by a nonzero overlap with the native state, below a temperature
Tn \propto 1/T0 > Tg. However, the random-globule phase remains locally stable
below Tn, down to the dynamical glass transition at Tg. Thus, in this model,
folding is rapid for temperatures between Tg and Tn, but below Tg the system
can get trapped in conformations uncorrelated with the native state. At a lower
temperature, the ordered phase can also undergo a dynamical glass transition,
splitting into substates separated by large barriers.Comment: 19 pages, revtex, 6 figure
Evaluation of the Antimicrobial Activity of Cationic Polymers against Mycobacteria: Toward Antitubercular Macromolecules.
Antimicrobial resistance is a global healthcare problem with a dwindling arsenal of usable drugs. Tuberculosis, caused by Mycobacterium tuberculosis, requires long-term combination therapy and multi- and totally drug resistant strains have emerged. This study reports the antibacterial activity of cationic polymers against mycobacteria, which are distinguished from other Gram-positive bacteria by their unique cell wall comprising a covalently linked mycolic acid-arabinogalactan-peptidoglycan complex (mAGP), interspersed with additional complex lipids which helps them persist in their host. The present study finds that poly(dimethylaminoethyl methacrylate) has particularly potent antimycobacterial activity and high selectivity over two Gram-negative strains. Removal of the backbone methyl group (poly(dimethylaminoethyl acrylate)) decreased antimycobacterial activity, and poly(aminoethyl methacrylate) also had no activity against mycobacteria. Hemolysis assays revealed poly(dimethylaminoethyl methacrylate) did not disrupt red blood cell membranes. Interestingly, poly(dimethylaminoethyl methacrylate) was not found to permeabilize mycobacterial membranes, as judged by dye exclusion assays, suggesting the mode of action is not simple membrane disruption, supported by electron microscopy analysis. These results demonstrate that synthetic polycations, with the correctly tuned structure are useful tools against mycobacterial infections, for which new drugs are urgently required
Pitfalls in the diagnosis of acoustic neuroma
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71894/1/j.1365-2273.1984.tb01490.x.pd
Organometallic iridium(III) anticancer complexes with new mechanisms of action: NCI-60 screening, mitochondrial targeting, and apoptosis
Platinum complexes related to cisplatin, cis-[PtCl2(NH3)2], are successful anticancer drugs; however, other transition metal complexes offer potential for combating cisplatin resistance, decreasing side effects, and widening the spectrum of activity. Organometallic half-sandwich iridium (IrIII) complexes [Ir(Cpx)(XY)Cl]+/0 (Cpx = biphenyltetramethylcyclopentadienyl and XY = phenanthroline (1), bipyridine (2), or phenylpyridine (3)) all hydrolyze rapidly, forming monofunctional G adducts on DNA with additional intercalation of the phenyl substituents on the Cpx ring. In comparison, highly potent complex 4 (Cpx = phenyltetramethylcyclopentadienyl and XY = N,N-dimethylphenylazopyridine) does not hydrolyze. All show higher potency toward A2780 human ovarian cancer cells compared to cisplatin, with 1, 3, and 4 also demonstrating higher potency in the National Cancer Institute (NCI) NCI-60 cell-line screen. Use of the NCI COMPARE algorithm (which predicts mechanisms of action (MoAs) for emerging anticancer compounds by correlating NCI-60 patterns of sensitivity) shows that the MoA of these IrIII complexes has no correlation to cisplatin (or oxaliplatin), with 3 and 4 emerging as particularly novel compounds. Those findings by COMPARE were experimentally probed by transmission electron microscopy (TEM) of A2780 cells exposed to 1, showing mitochondrial swelling and activation of apoptosis after 24 h. Significant changes in mitochondrial membrane polarization were detected by flow cytometry, and the potency of the complexes was enhanced ca. 5× by co-administration with a low concentration (5 μM) of the γ-glutamyl cysteine synthetase inhibitor L-buthionine sulfoximine (L-BSO). These studies reveal potential polypharmacology of organometallic IrIII complexes, with MoA and cell selectivity governed by structural changes in the chelating ligands
Learning from the challenges of undertaking an evaluation of a multi-partner housing support initiative delivered within a hospital setting
Objectives
We present learning from a mixed-methods evaluation of a housing support initiative for hospital inpatients.
Study design
A mixed-methods process evaluation.
Methods
A social housing provider delivered a housing support service in two hospitals (mental health unit and general hospital). Healthcare providers, the social housing provider and academic researchers designed and undertook a co-produced, mixed-methods process evaluation of the intervention. The evaluation included questionnaires, semi-structured interviews, analysis of routinely collected data and economic analysis. Despite commitment from the partners, the evaluation faced challenges. We reflect on the lessons learnt within our discussion paper.
Results
Despite the commitment of the partners, we faced several challenges.
We took an iterative approach to the design and processes of the evaluation to respond to arising challenges. Recruitment of service-users was more difficult than anticipated, requiring additional staff resources. Given the small-scale nature of the intervention, and the quality of data recorded in hospital records, the planned economic analysis was not feasible. Positive factors facilitating evaluation included involvement of staff delivering the intervention, as well as managers. Being able to offer payment to partner organisations for staff time also facilitated ongoing engagement.
Conclusions
Multi-partner evaluations are useful, however, researchers and partners need to be prepared to take an iterative, resource intensive approach. Both availability and quality of routine data, and the resources required to support data collection, may limit feasibility of specific methods when evaluating small-scale cross-sector initiatives. Thus, this necessitates a flexible approach to design and analysis
DNA methylation is required to maintain both DNA replication timing precision and 3D genome organization integrity
DNA replication timing and three-dimensional (3D) genome organization are associated with distinct epigenome patterns across large domains. However, whether alterations in the epigenome, in particular cancer-related DNA hypomethylation, affects higher-order levels of genome architecture is still unclear. Here, using Repli-Seq, single-cell Repli-Seq, and Hi-C, we show that genome-wide methylation loss is associated with both concordant loss of replication timing precision and deregulation of 3D genome organization. Notably, we find distinct disruption in 3D genome compartmentalization, striking gains in cell-to-cell replication timing heterogeneity and loss of allelic replication timing in cancer hypomethylation models, potentially through the gene deregulation of DNA replication and genome organization pathways. Finally, we identify ectopic H3K4me3-H3K9me3 domains from across large hypomethylated domains, where late replication is maintained, which we purport serves to protect against catastrophic genome reorganization and aberrant gene transcription. Our results highlight a potential role for the methylome in the maintenance of 3D genome regulation
Temporal clustering of Kawasaki disease cases around the world
In a single-site study (San Diego, CA, USA), we previously showed that Kawasaki Disease (KD) cases cluster temporally in bursts of approximately 7 days. These clusters occurred more often than would be expected at random even after accounting for long-term trends and seasonality. This finding raised the question of whether other locations around the world experience similar temporal clusters of KD that might offer clues to disease etiology. Here we combine data from San Diego and nine additional sites around the world with hospitals that care for large numbers of KD patients, as well as two multi-hospital catchment regions. We found that across these sites, KD cases clustered at short time scales and there were anomalously long quiet periods with no cases. Both of these phenomena occurred more often than would be expected given local trends and seasonality. Additionally, we found unusually frequent temporal overlaps of KD clusters and quiet periods between pairs of sites. These findings suggest that regional and planetary range environmental influences create periods of higher or lower exposure to KD triggers that may offer clues to the etiology of KD
A Protein-Protein Interaction Map of the Trypanosoma brucei Paraflagellar Rod
We have conducted a protein interaction study of components within a specific sub-compartment of a eukaryotic flagellum. The trypanosome flagellum contains a para-crystalline extra-axonemal structure termed the paraflagellar rod (PFR) with around forty identified components. We have used a Gateway cloning approach coupled with yeast two-hybrid, RNAi and 2D DiGE to define a protein-protein interaction network taking place in this structure. We define two clusters of interactions; the first being characterised by two proteins with a shared domain which is not sufficient for maintaining the interaction. The other cohort is populated by eight proteins, a number of which possess a PFR domain and sub-populations of this network exhibit dependency relationships. Finally, we provide clues as to the structural organisation of the PFR at the molecular level. This multi-strand approach shows that protein interactome data can be generated for insoluble protein complexes
Managing future risks and building socio-ecological resilience
The Mediterranean Basin is experiencing major changes in environmental conditions, which can introduce new challenges to the resilience of its natural and human systems. This situation is combined with rapid and spatially diverse socio-economic development in the region, mainly in terms of demographic trends and settlement patterns, thus leading to higher exposure to environmental hazards. Furthermore, new risks are expected to emerge from interactions between drivers and impacts across sectors, thus increasing the vulnerability of natural systems and human populations
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