The interaction of OH-containing compounds with calcite, CaCO3, such as is required for the processes that control biomineralization, has been investigated in a low-water solution. We used ethanol ...(EtOH) as a simple, model, OH-containing organic compound, and observed the strength of its adsorption on calcite relative to OH from water and the consequences of the differences in interaction on crystal growth and dissolution. A combination of atomic force microscopy (AFM) and molecular dynamics (MD) simulations showed that EtOH attachment on calcite is stronger than HOH binding and that the first adsorbed layer of ethanol is highly ordered. The strong ordering of the ethanol molecules has important implications for mineral growth and dissolution because it produces a hydrophobic layer. Ethanol ordering is disturbed along steps and at defect sites, providing a bridge from the bulk solution to the surface. The strong influence of calcite in structuring ethanol extends further into the liquid than expected from electrical double-layer theory. This suggests that in fluids where water activity is low, such as in biological systems optimized for biomineralization, organic molecules can control ion transport to and from the mineral surface, confining it to specific locations, thus providing the organism with control for biomineral morphology.
ABSTRACT
We present the goals, design, and first results of the MUSE Ultra Deep Field (MUDF) survey, a large programme using the Multi Unit Spectroscopic Explorer (MUSE) instrument at the ESO Very ...Large Telescope. The MUDF survey is collecting ≈150 h on-source of integral field optical spectroscopy in a 1.5 × 1.2 arcmin2 region which hosts several astrophysical structures along the line of sight, including two bright z ≈ 3.2 quasars with close separation (≈500 kpc). Following the description of the data reduction procedures, we present the analysis of the galaxy environment and gaseous properties of seven groups detected at redshifts 0.5 < z < 1.5, spanning a large dynamic range in halo mass, $\log (M_h/\rm {M_\odot }) \approx 11 - 13.5$. For four of the groups, we find associated Mg ii absorbers tracing cool gas in high-resolution spectroscopy of the two quasars, including one case of correlated absorption in both sightlines at distance ≈480 kpc. The absorption strength associated with the groups is higher than what has been reported for more isolated galaxies of comparable mass and impact parameters. We do not find evidence for widespread cool gas giving rise to strong absorption within these groups. Combining these results with the distribution of neutral and ionized gas seen in emission in lower redshift groups, we conclude that gravitational interactions in the group environment strip gas from the galaxy haloes into the intragroup medium, boosting the cross-section of cool gas and leading to the high fraction of strong Mg ii absorbers that we detect.
Resistance to chemotherapy in ovarian cancer is poorly understood. Evolutionary models of cancer predict that, following treatment, resistance emerges either because of outgrowth of an intrinsically ...resistant sub-clone or evolves in residual disease under the selective pressure of treatment. To investigate genetic evolution in high-grade serous (HGS) ovarian cancers, we first analysed cell line series derived from three cases of HGS carcinoma before and after platinum resistance had developed (PEO1, PEO4 and PEO6; PEA1 and PEA2; and PEO14 and PEO23). Analysis with 24-colour fluorescence in situ hybridisation and single nucleotide polymorphism (SNP) array comparative genomic hybridisation (CGH) showed mutually exclusive endoreduplication and loss of heterozygosity events in clones present at different time points in the same individual. This implies that platinum-sensitive and -resistant disease was not linearly related, but shared a common ancestor at an early stage of tumour development. Array CGH analysis of six paired pre- and post-neoadjuvant treatment HGS samples from the CTCR-OV01 clinical study did not show extensive copy number differences, suggesting that one clone was strongly dominant at presentation. These data show that cisplatin resistance in HGS carcinoma develops from pre-existing minor clones but that enrichment for these clones is not apparent during short-term chemotherapy treatment.
Molecular dynamics simulations have been used to model the interaction between ethanol, water, and the {101̅4} surface of calcite. Our results demonstrate that a single ethanol molecule is able to ...form two interactions with the mineral surface (both Ca−O and O−H), resulting in a highly ordered, stable adsorption layer. In contrast, a single water molecule can only form one or other of these interactions and is thus less well bound, resulting in a more unstable adsorption layer. Consequently, when competitive adsorption is considered, ethanol dominates the adsorption layer that forms even when the starting configuration consists of a complete monolayer of water at the surface. The computational results are in good agreement with the results from atomic force microscopy experiments where it is observed that a layer of ethanol remains attached to the calcite surface, decreasing its ability to interact with water and for growth at the {101̅4} surface to occur. This observation, and its corresponding molecular explanation, may give some insight into the ability to control crystal form using mixtures of different organic solvents.
Previous studies have suggested that beliefs about voices mediate the relationship between actual voice experience and behavioural and affective response.
We investigated beliefs about voice power ...(omnipotence), voice intent (malevolence/benevolence) and emotional and behavioural response (resistance/engagement) using the Beliefs About Voices Questionnaire - Revised (BAVQ-R) in 46 voice hearers. Distress was assessed using a wide range of measures: voice-related distress, depression, anxiety, self-esteem and suicidal ideation. Voice topography was assessed using measures of voice severity, frequency and intensity. We predicted that beliefs about voices would show a stronger association with distress than voice topography.
Omnipotence had the strongest associations with all measures of distress included in the study whereas malevolence was related to resistance, and benevolence to engagement. As predicted, voice severity, frequency and intensity were not related to distress once beliefs were accounted for.
These results concur with previous findings that beliefs about voice power are key determinants of distress in voice hearers, and should be targeted specifically in psychological interventions.
Fisheries are highly complex social-ecological systems that often face ‘wicked’ problems from unsustainable resource management to climate change. Addressing these challenges requires ...transdisciplinary approaches that integrate perspectives across scientific disciplines and knowledge systems. Despite widespread calls for transdisciplinary fisheries research (TFR), there are still limitations in personal and institutional capacity to conduct and support this work to the highest potential. The viewpoints of early career researchers (ECRs) in this field can illuminate challenges and promote systemic change within fisheries research. This paper presents the perspectives of ECRs from across the globe, gathered through a virtual workshop held during the 2021 World Fisheries Congress, on goals, challenges, and future potential for TFR. Big picture goals for TFR were guided by principles of co-production and included (i) integrating transdisciplinary thinking at all stages of the research process, (ii) ensuring that research is inclusive and equitable, (iii) co-creating knowledge that is credible, relevant, actionable, and impactful, and (iv) consistently communicating with partners. Institutional inertia, lack of recognition of the extra time and labour required for TFR, and lack of skill development opportunities were identified as three key barriers in conducting TFR. Several critical actions were identified to help ECRs, established researchers, and institutions reach these goals. We encourage ECRs to form peer-mentorship networks to guide each other along the way. We suggest that established researchers ensure consistent mentorship while also giving space to ECR voices. Actions for institutions include retooling education programs, developing and implementing new metrics of impact, and critically examining individualism and privilege in academia. We suggest that the opportunities and actions identified here, if widely embraced now, can enable research that addresses complex challenges facing fishery systems contributing to a healthier future for fish and humans alike.
Induced pluripotent stem-cell derived endothelial cells (iPSC-ECs) can be generated from any somatic cell and their iPSC sources possess unlimited self-renewal. Previous demonstration of their ...proangiogenic activity makes them a promising cell type for treatment of ischemic injury. As with many other stem cell approaches, the low rate of in-vivo survival has been a major limitation to the efficacy of iPSC-ECs to date. In this study, we aimed to increase the in-vivo lifetime of iPSC-ECs by culturing them on electrospun polycaprolactone (PCL)/gelatin scaffolds, before quantifying the subsequent impact on their proangiogenic function.
iPSC-ECs were isolated and stably transfected with a luciferase reporter to facilitate quantification of cell numbers and non-invasive imaging in-vivo PCL/gelatin scaffolds were engineered using electrospinning to obtain woven meshes of nanofibers. iPSC-ECs were cultured on scaffolds for 7 days. Subsequently, cell growth and function were assessed in vitro followed by implantation in a mouseback subcutaneous model for 7 days.
Using a matrix of conditions, we found that scaffold blends with ratios of PCL:gelatin of 70:30 (PG73) spun at high flow rates supported the greatest levels of iPSC-EC growth, retention of phenotype, and function in vitro. Implanting iPSC-ECs seeded on PG73 scaffolds in vivo improved their survival up to 3 days, compared to cells directly injected into control wounds, which were no longer observable within 1 h. Enhanced engraftment improved blood perfusion, observed through non-invasive laser Doppler imaging. Immunohistochemistry revealed a corresponding increase in host angiogenic mechanisms characterized by the enhanced recruitment of macrophages and the elevated expression of proangiogenic cytokines vascular endothelial growth factor and placental growth factor.
Knowledge of these mechanisms combined with a deeper understanding of the scaffold parameters influencing this function provides the groundwork for optimizing future iPSC-EC therapies utilizing engraftment platforms. The development of combined scaffold and iPSC-EC therapies could ultimately improve therapeutic angiogenesis and the treatment of ischemic injury.
Intra-tumour genetic heterogeneity has been reported in both leukaemias and solid tumours and is implicated in the development of drug resistance in CML and AML. The role of genetic heterogeneity in ...drug response in solid tumours is unknown.
To investigate intra-tumour genetic heterogeneity and chemoradiation response in advanced cervical cancer, we analysed 10 cases treated on the CTCR-CE01 clinical study. Core biopsies for molecular profiling were taken from four quadrants of the cervix pre-treatment, and weeks 2 and 5 of treatment. Biopsies were scored for cellularity and profiled using Agilent 180k human whole genome CGH arrays. We compared genomic profiles from 69 cores from 10 patients to test for genetic heterogeneity and treatment effects at weeks 0, 2 and 5 of treatment.
Three patients had two or more distinct genetic subpopulations pre-treatment. Subpopulations within each tumour showed differential responses to chemoradiotherapy. In two cases, there was selection for a single intrinsically resistant subpopulation that persisted at detectable levels after 5 weeks of chemoradiotherapy. Phylogenetic analysis reconstructed the order in which genomic rearrangements occurred in the carcinogenesis of these tumours and confirmed gain of 3q and loss of 11q as early events in cervical cancer progression.
Selection effects from chemoradiotherapy cause dynamic changes in genetic subpopulations in advanced cervical cancers, which may explain disease persistence and subsequent relapse. Significant genetic heterogeneity in advanced cervical cancers may therefore be predictive of poor outcome.
•Nutritional strategies to optimize the health of high-risk cattle are warranted.•Trace minerals play vital roles in mechanisms affecting growth and health.•Organic trace minerals may have enhanced ...bioavailability compared to inorganic.•Performance was similar in steers receiving organic or inorganic Cu, Co, Mn, and Zn.•Stress responses were improved in steers receiving organic Cu, Co, Mn, and Zn.
Nutritional approaches to optimize cattle health and performance during the receiving period are warranted. This experiment evaluated the impacts of supplementing organic complexed Cu, Co, Mn, and Zn on productive and health responses of high-risk beef cattle during a 60-day backgrounding phase. Crossbred steers (120) were purchased at auction and transported to the experimental facility, where BW was recorded (day−1; initial shrunk BW = 227.7 ± 1.3 kg). On day 0, steers were ranked by BW and allocated to one of eight groups and housed in drylot pens equipped with GrowSafe automated feeding systems (Model 8000; two bunks/pen). Groups were randomly assigned to receive a total mixed ration containing: (1) sulfate sources of Cu, Co, Mn, and Zn (INR; n = 40); (2) organic complexed sources of the same minerals (AAC; Zinpro Availa 4 based on a metal:amino acid complex ratio of 1:1 for Zn, Cu, and Mn in addition to cobalt glucoheptonate; Zinpro Corp., Eden Prairie, MN; n = 40); or (3) AAC and an organic complexed trace mineral drench (APF; 30 mL/hd; Zinpro ProFusion, Zinpro Corp.) on day 0 and with morbidity treatment (n = 40). Diets provided the same daily amount of all nutrients and minerals based on 7 g/steer daily of Zinpro Availa 4. Steers were assessed for bovine respiratory disease (BRD) signs daily. Liver biopsies were performed on days 0, 28 and 60. Blood samples were collected on days 0, 2, 6, 10, 13, 21, 28 and 45. No treatment differences were detected (P ≥ 0.23) for feed intake, final BW, average daily gain, or BRD incidence. Mean liver Co concentrations were greater (P = 0.02) in AAC and APF compared to INR steers. Mean liver Cu was greater (P = 0.02) in APF compared to AAC steers. Liver Zn tended to be greater (P = 0.10) on day 28 but less (P = 0.05) on day 60 for INR compared to AAC and APF steers. Plasma cortisol was lowest (P = 0.05) for AAC steers on day 6, whereas AAC steers tended to have greater (P = 0.09) plasma cortisol on day 13 compared with APF. Plasma haptoglobin tended to be greater (P ≤ 0.10) for INR steers on days 28 and 45 compared to AAC and APF. While supplementing cattle with AAC or INR results in similar animal performance and clinical disease, AAC and APF reduce stress and acute phase protein responses.
The Air Force Research Laboratory's Demonstration and Science Experiments (DSX) mission investigated wave‐particle interactions and the particle and space environment in Medium Earth Orbit (MEO) from ...June 2019 to May 2021. Its Wave‐Particle Interactions Experiment conducted over 1,300 active high power very low frequency transmissions in the radiation belts providing observations of antenna performance and signal propagation from a controlled source. This included hundreds of transmissions while in magnetic conjunction with other satellites. The Loss Cone Imager and Space Weather Experiment suite observed electron and proton populations over a wide energy range, with several of these instruments providing pitch‐angle resolution. The Space Environmental Effects Experiment investigated effects of the MEO environment on electronics and materials. The Adaptive Controls Experiment demonstrated technology for on‐board identification and control of large structure vibrational modes. We describe the DSX instrument capabilities and on orbit performance, science planning and operations for carrying out an array of active and passive experiments, and some initial results in brief. We also describe plans for further work and data release.
Plain Language Summary
In this paper, we summarize the Air Force Research Laboratory's Demonstration and Science Experiments (DSX) satellite mission which recently concluded after nearly 2 yr in the radiation belts. We describe the DSX science instruments and how we planned and performed experiments during the mission. The mission had a primary goal of conducting high‐power transmissions in near‐Earth space using very low frequency (VLF) radio waves. Such active DSX experiments yielded information about how a high‐voltage antenna interacts with the low‐density charged particles, or plasma, near the spacecraft. DSX experimented with propagating signals along magnetic field lines to other satellites and “bouncing” them back to the spacecraft. DSX also studied interactions between VLF waves and radiation belt electrons, particularly how electrons may be lost from the radiation belts. High‐energy electrons and protons trapped in the Earth's magnetic field make up the radiation belts, and these particles as well as the lower‐energy plasma particles are hazards to spacecraft. The mission had further goals of measuring radiation belt and plasma particles and their effects on spacecraft parts. Collectively, the results of DSX research will improve spacecraft survivability in the harsh space environment.
Key Points
Demonstration and Science Experiments conducted over 1,300 high power very low frequency transmission experiments in the radiation belts, including 315 in coordination with other satellites
The 23‐month mission also collected comprehensive wave, particle, and plasma observations in its inclined medium Earth orbit
Instruments, planning and operations, some initial results, plans for further work, and release of data are described in brief
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