Branching out: Feasibility of examining the effects of greenspace on mental health after traumatic brain injury.

Aim: This pilot study's aim was to determine the feasibility of examining the effects of an environmental variable (i.e., tree canopy coverage) on mental health after sustaining a brain injury. Methods: A secondary data analysis was conducted leveraging existing information on mental health after moderate to severe traumatic brain injury (TBI) from the TBI Model System. Mental health was measured using PHQ-9 (depression) and GAD-7 (anxiety) scores. The data were compared with data on tree canopy coverage in the state of Texas that was obtained from the Multi-Resolution Land Characteristics (MRLC) Consortium using GIS analysis. Tree canopy coverage as an indicator of neighborhood socioeconomic status was also examined using the Neighborhood SES Index. Results: Tree canopy coverage had weak and non-significant correlations with anxiety and depression scores, as well as neighborhood socioeconomic status. Data analysis was limited by small sample size. However, there is a higher percentage (18.8%) of participants who reported moderate to severe depression symptoms in areas with less than 30% tree canopy coverage, compared with 6.6% of participants who endorsed moderate to severe depression symptoms and live in areas with more than 30% tree canopy coverage (there was no difference in anxiety scores). Conclusion: Our work confirms the feasibility of measuring the effects of tree canopy coverage on mental health after brain injury and warrants further investigation into examining tree canopy coverage and depression after TBI. Future work will include nationwide analyses to potentially detect significant relationships, as well as examine differences in geographic location.

South African Lagerstätte reveals middle Permian Gondwanan lakeshore ecosystem in exquisite detail.

Continental ecosystems of the middle Permian Period (273-259 million years ago) are poorly understood. In South Africa, the vertebrate fossil record is well documented for this time interval, but the plants and insects are virtually unknown, and are rare globally. This scarcity of data has hampered studies of the evolution and diversification of life, and has precluded detailed reconstructions and analyses of ecosystems of this critical period in Earth's history. Here we introduce a new locality in the southern Karoo Basin that is producing exceptionally well-preserved and abundant fossils of novel freshwater and terrestrial insects, arachnids, and plants. Within a robust regional geochronological, geological and biostratigraphic context, this Konservat- and Konzentrat-Lagerstätte offers a unique opportunity for the study and reconstruction of a southern Gondwanan deltaic ecosystem that thrived 266-268 million years ago, and will serve as a high-resolution ecological baseline towards a better understanding of Permian extinction events.

Development of the multidimensional health perceptions questionnaire in English and Spanish.

PURPOSE: To develop the novel multidimensional health perceptions questionnaire (MHPQ), a self-reported assessment of health perceptions inclusive of (1) individuals beliefs about the causes and consequences of health conditions, benefits and barriers to maintaining and improving health, ability to accomplish health-related goals and control health circumstances, and the role of God and/or spirituality in health and healthcare, (2) anticipated discrimination in the healthcare systems, and (3) trust in healthcare providers and medicine, illustrated in our newly proposed Multidimensional Health Perceptions Conceptual Model. METHODS: We developed an initial MHPQß item set, corresponding to domains of our conceptual model, using a patient-centered outcomes development approach. This include literature review, expert and end-user feedback, translation and language validation (specifically to Latin American Spanish), and cognitive interviewing. RESULTS: The initial 104 items of MHPQß had excellent content validity, with a Content Validity Index of 98.1%. After expert (n = 13) feedback, translation and language validation, and cognitive interviewing among community-dwelling English-speakers (n = 5) and Spanish-speakers (n = 4), the final MHPQß comprised 93 items rated on a five-point agreement scale (1 = Strongly disagree to 5 = Strongly agree), with a reading grade level of 6th grade in English and 8th grade in Spanish. CONCLUSION: The MHPQß is a promising tool to assess individuals' health perceptions. It has excellent content validity and good reading accessibility. Future work will establish the factor structure and final item set of the MHPQ.

Over Winter Microbial Processes in a Svalbard Snow Pack: An Experimental Approach.

Snow packs cover large expanses of Earth's land surface, making them integral components of the cryosphere in terms of past climate and atmospheric proxies, surface albedo regulators, insulators for other Arctic environments and habitats for diverse microbial communities such as algae, bacteria and fungi. Yet, most of our current understanding of snow pack environments, specifically microbial activity and community interaction, is limited to the main microbial growing season during spring ablation. At present, little is known about microbial activity and its influence on nutrient cycling during the subfreezing temperatures and 24-h darkness of the polar winter. Here, we examined microbial dynamics in a simulated cold (-5°C), dark snow pack to determine polar winter season microbial activity and its dependence on critical nutrients. Snow collected from Ny-Ålesund, Svalbard was incubated in the dark over a 5-week period with four different nutrient additions, including glacial mineral particles, dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) and a combined treatment of DIN plus DIP. Data indicate a consumption of dissolved inorganic nutrients, particularly DIN, by heterotrophic communities, suggesting a potential nitrogen limitation, contradictory to phosphorus limitations found in most aquatic environments. 16S amplicon sequencing also reveal a clear difference in microbial community composition in the particulate mineral treatment compared to dissolved nutrient treatments and controls, suggesting that certain species of heterotrophs living within the snow pack are more likely to associate with particulates. Particulate phosphorus analyses indicate a potential ability of heterotrophic communities to access particulate sources of phosphorous, possibly explaining the lack of phosphorus limitation. These findings have importance for understanding microbial activity during the polar winter season and its potential influences on the abundance and bioavailability of nutrients released to surface ice and downstream environments during the ablation season.

Bacterial Dynamics in Supraglacial Habitats of the Greenland Ice Sheet.

Current research into bacterial dynamics on the Greenland Ice Sheet (GrIS) is biased toward cryoconite holes, despite this habitat covering less than 8% of the ablation (melt) zone surface. In contrast, the expansive surface ice, which supports wide-spread Streptophyte micro-algal blooms thought to enhance surface melt, has been relatively neglected. This study aims to understand variability in bacterial abundance and production across an ablation season on the GrIS, in relation to micro-algal bloom dynamics. Bacterial abundance reached 3.3 ± 0.3 × 105 cells ml-1 in surface ice and was significantly linearly related to algal abundances during the middle and late ablation periods (R 2 = 0.62, p < 0.05; R 2 = 0.78, p < 0.001). Bacterial production (BP) of 0.03-0.6 µg C L-1 h-1 was observed in surface ice and increased in concert with glacier algal abundances, indicating that heterotrophic bacteria consume algal-derived dissolved organic carbon. However, BP remained at least 28 times lower than net primary production, indicating inefficient carbon cycling by heterotrophic bacteria and net accumulation of carbon in surface ice throughout the ablation season. Across the supraglacial environment, cryoconite sediment BP was at least four times greater than surface ice, confirming that cryoconite holes are the true "hot spots" of heterotrophic bacterial activity.

A step beyond BRET: Fluorescence by Unbound Excitation from Luminescence (FUEL).

Fluorescence by Unbound Excitation from Luminescence (FUEL) is a radiative excitation-emission process that produces increased signal and contrast enhancement in vitro and in vivo. FUEL shares many of the same underlying principles as Bioluminescence Resonance Energy Transfer (BRET), yet greatly differs in the acceptable working distances between the luminescent source and the fluorescent entity. While BRET is effectively limited to a maximum of 2 times the Förster radius, commonly less than 14 nm, FUEL can occur at distances up to µm or even cm in the absence of an optical absorber. Here we expand upon the foundation and applicability of FUEL by reviewing the relevant principles behind the phenomenon and demonstrate its compatibility with a wide variety of fluorophores and fluorescent nanoparticles. Further, the utility of antibody-targeted FUEL is explored. The examples shown here provide evidence that FUEL can be utilized for applications where BRET is not possible, filling the spatial void that exists between BRET and traditional whole animal imaging.

In vitro characterization of Fluorescence by Unbound Excitation from Luminescence: broadening the scope of energy transfer.

Energy transfer mechanisms represent the basis for an array of valuable tools to infer interactions in vitro and in vivo, enhance detection or resolve interspecies distances such as with resonance. Based upon our own previously published studies and new results shown here we present a novel framework describing for the first time a model giving a view of the biophysical relationship between Fluorescence by Unbound Excitation from Luminescence (FUEL), a conventional radiative excitation-emission process, and bioluminescence resonance energy transfer. We show here that in homogeneous solutions and in fluorophore-targeted bacteria, FUEL is the dominant mechanism responsible for the production of red-shifted photons. The minor resonance contribution was ascertained by comparing the intensity of the experimental signal to its theoretical resonance counterpart. Distinctive features of the in vitro FUEL signal include a macroscopic depth dependency, a lack of enhancement upon targeting at a constant fluorophore concentration cf and a non-square dependency on cf. Significantly, FUEL is an important, so far overlooked, component of all resonance phenomena which should guide the design of appropriate controls when elucidating interactions. Last, our results highlight the potential for FUEL as a means to enhance in vivo and in vitro detection through complex media while alleviating the need for targeting.

Intrinsic autotrophic biomass yield and productivity in algae: experimental methods for strain selection.

Using an analogy with fed-batch heterotrophic growth, the algal photoautotrophic yield Φ(DW) (in grams of dry weight biomass synthesized per micromole of absorbed photons) was derived from the algae batch growth behavior in nutrient-replete medium. At known levels of incident light, the yield Φ(DW) enables the estimate of a maximum productivity, and is therefore critical to compare and select algal cultures and growth conditions for large-scale production. The algal culture maximum growth rate was shown to be an unreliable indicator of autotrophic biomass yield. The developed carbonate addition method (carbonate addition, neutralization, and sealing) alleviated carbon limitations otherwise seen in aerated batch cultures, leading to two to five fold higher yield estimates. The fully defined FLX growth medium with variable ionic strengths (FLX1-100) supported excellent growth in most cultures tested. The chosen experimental methods and versatile FLX medium proved well-suited for small sample volumes and a high number of samples.

Intrinsic autotrophic biomass yield and productivity in algae: modeling spectral and mixing-rate dependence.

For non-inhibitory irradiances, the rate of algal biomass synthesis was modeled as the product of the algal autotrophic yield Φ(DW) and the flux of photons absorbed by the culture, as described using Beer-Lambert law. As a contrast to earlier attempts, the use of scatter-corrected extinction coefficients enabled the validation of such approach, which bypasses determination of photosynthesis-irradiance (PI) kinetic parameters. The broad misconception that PI curves, or the equivalent use of specific growth rate expressions independent of the biomass concentration, can be extended to adequately model biomass production under light-limitation is addressed. For inhibitory irradiances, a proposed mechanistic model, based on the photosynthetic units (PSU) concept, allows one to estimate a target speed νT across the photic zone in order to limit the flux of photons per cell to levels averting significant reductions in Φ(DW) . These modeled target speeds, on the order of 5-20 m s(-1) for high outdoor irradiances, call for fundamental changes in reactor design to optimize biomass productivity. The presented analysis enables a straightforward bioreactor parameterization, which, in-turn, guides the establishment of conditions ensuring maximum productivity and complete nutrients consumption. Additionally, solar and fluorescent lighting spectra were used to calculate energy to photon-counts conversion factors.

Development of a defined medium supporting rapid growth for Deinococcus radiodurans and analysis of metabolic capacities.

A morpholinepropanesulfonic acid (MOPS)-buffered rich defined medium (RDM) was optimized to support a reproducible 2.6-h doubling time at 35 degrees C for Deinococcus radiodurans R1 and used to gain insight into vitamin and carbon metabolism. D. radiodurans was shown to require biotin and niacin for growth in this medium. A glutamine-serine simple defined medium (SDM) was developed that supported a 4-h doubling time, and this medium was used to probe sulfur and methionine metabolism. Vitamin B(12) was shown to alleviate methionine auxotrophy, and under these conditions, sulfate was used as the sole sulfur source. Phenotypic characterization of a methionine synthase deletion mutant demonstrated that the B(12) alleviation of methionine auxotrophy was due to the necessity of the B(12)-dependent methionine synthase in methionine biosynthesis. Growth on ammonium as the sole nitrogen source in the presence of vitamin B(12) was demonstrated, but it was not possible to achieve reproducibly good growth in the absence of at least one amino acid as a nitrogen source. Growth on sulfate, cysteine, and methionine as sulfur sources demonstrated the function of a complete sulfur recycling pathway in this strain. These studies have demonstrated that rapid growth of D. radiodurans R1 can be achieved in a MOPS-based medium solely containing a carbon source, salts, four vitamins, and two amino acids.