Intermingling of two Pseudocalanus species on Georges Bank

Physical and biological controls on the springtime distributions of Pseudocalanus moultoni and P. newmani on Georges Bank are examined by assimilating observations into a coupled physical-biological model. Monthly snapshots of abundance are derived from U.S. GLOBEC Georges Bank broad-scale surveys during 1997. The forward problem is posed as an advection-diffusion-reaction equation for the copepod concentration. The adjoint method of data assimilation is used to invert for the biological sources and sinks implied by the observed changes in abundance between surveys and the flow during the intervening period. Based on this analysis, the two species appear to have distinct population centers in the late winter/early spring: P. moultoni on the northwest flank of the Bank and P. newmani on the Northeast Peak and the southern tip of Browns Bank. As the growing season progresses, the clockwise circulation around Georges Bank blends reproducing (but not interbreeding) animals from the two source regions, causing their distributions to overlap by early summer. The springtime evolution of Pseudocalanus distributions in this region is driven by a complex mixture of hydrodynamic transport and species-specific population dynamics, including both growth and mortality

Striatal cholinergic interneurons generate beta and gamma oscillations in the corticostriatal circuit and produce motor deficits

Cortico-basal ganglia-thalamic (CBT) neural circuits are critical modulators of cognitive and motor function. When compromised, these circuits contribute to neurological and psychiatric disorders, such as Parkinson's disease (PD). In PD, motor deficits correlate with the emergence of exaggerated beta frequency (15-30 Hz) oscillations throughout the CBT network. However, little is known about how specific cell types within individual CBT brain regions support the generation, propagation, and interaction of oscillatory dynamics throughout the CBT circuit or how specific oscillatory dynamics are related to motor function. Here, we investigated the role of striatal cholinergic interneurons (SChIs) in generating beta and gamma oscillations in cortical-striatal circuits and in influencing movement behavior. We found that selective stimulation of SChIs via optogenetics in normal mice robustly and reversibly amplified beta and gamma oscillations that are supported by distinct mechanisms within striatal-cortical circuits. Whereas beta oscillations are supported robustly in the striatum and all layers of primary motor cortex (M1) through a muscarinic-receptor mediated mechanism, gamma oscillations are largely restricted to the striatum and the deeper layers of M1. Finally, SChI activation led to parkinsonian-like motor deficits in otherwise normal mice. These results highlight the important role of striatal cholinergic interneurons in supporting oscillations in the CBT network that are closely related to movement and parkinsonian motor symptoms.DP2 NS082126 - NINDS NIH HHS; R01 NS081716 - NINDS NIH HHS; R21 NS078660 - NINDS NIH HHShttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC4896681/Published versio

Metabarcoding of marine zooplankton: prospects, progress and pitfalls

Metabarcoding (large-scale taxonomic identification of complex samples via analysis of one or few orthologous DNA regions, called barcodes) is revolutionizing analysis of biodiversity of marine zooplankton assemblages. Metabarcoding relies on high-throughput DNA sequencing (HTS) technologies, which yield millions of DNA sequences in parallel and allow large-scale analysis of environmental samples. Metabarcoding studies of marine zooplankton have used various regions of nuclear small- (18S) and large-subunit (28S) rRNA, which allow accurate classification of novel sequences and reliable amplification with consensus primers, but- due to their relatively conserved nature- may underestimate species diversity in a community. To discriminate species, more variable genes are needed. A limited number of metabarcoding studies have used mitochondrial cytochrome oxidase I (COI), which ensures detection of species-level diversity, but may require group-specific primers and thus result in inconsistent amplification success rates. Reference databases with sequences for accurately-identified species are critically needed to allow taxonomic designation of molecular operational taxonomic units (MOTU) and comparison with previous studies of zooplankton diversity. Potential and promising applications of metabarcoding include rapid detection of impacts of climate change, monitoring and assessment of ecosystem health, calculation of biotic indices, characterization of food webs and detection of introduced, non-indigenous species

Low Pressure Greenhouse Concepts for Mars

A project was initiated to begin testing some environmental limits for managing plant growth systems. These limits will help determine some of the concepts for building plant enclosures for use on Mars. In particular, this study focuses on the effects of reduced atmospheric pressures. Structural design is considered as it relates to the biological processes that would occur within that structure. The design must be closely tied to the functionality of the biological system and has a few primary concerns that need to be tested to resolve the question as to the path of the design. Early tests indicate that plants can survive and grow at low (greater than 76 mb) pressure

Preliminary Estimates of the Possibilities for Developing a Deployable Greenhouse for a Planetary Surface (Mars)

Two of the main conditions for plant growth and development on the Martian surface are irradiation (optimal range from 80 W/sq m to 180 W/sq m of photosynthetically active radiation) and temperature (optimal range from 20 C to 27 C). The only known natural source of energy on Mars is sunlight, with a general intensity of 589 +/- 142 W/sq m (Martian Solar Constant). Comparisons of plant growth requirements with conditions on the Martian surface are presented in Table 1, while some basic considerations for implementing plant growth in a Martian DG are presented in Table 2. The general scenario and approximate schedule of startup and development of operations in DG are shown in Table 3

Defining the role of dexmedetomidine in the prevention of delirium in the intensive care unit (ICU)

Dexmedetomidine is a highly selective α2 agonist used as a sedative agent. It also provides anxiolysis and sympatholysis without significant respiratory compromise or delirium. We conducted a systematic review to examine whether sedation of patients in the intensive care unit (ICU) with dexmedetomidine was associated with a lower incidence of delirium as compared to other nondexmedetomidine sedation strategies. A search of PUBMED, EMBASE, and the Cochrane Database of Systematic Reviews yielded only three trials from 1966 through April 2015 that met our predefined inclusion criteria and assessed dexmedetomidine and outcomes of delirium as their primary endpoint. The studies varied in regard to population, comparator sedation regimen, delirium outcome measure, and dexmedetomidine dosing. All trials are limited by design issues that limit our ability definitively to conclude that dexmedetomidine prevents delirium. Evidence does suggest that dexmedetomidine may allow for avoidance of deep sedation and use of benzodiazepines, factors both observed to increase the risk for developing delirium. Our assessment of currently published literature highlights the need for ongoing research to better delineate the role of dexmedetomidine for delirium prevention

ENVIRONMENTAL TEMPERATURES IN FLORIDA DAIRY HOUSING

Environmental conditions in all air-conditioned barn and in evaporatively cooled sprinkler and fall and tunnel-ventilated barns are compared and recommendations for dairy barn design for hot, humid climates arc, given. Temperature Humidity Indexes (THI) observed in the air-conditioned barn were always below 72. Average THIs ill the evaporatively cooled barns during afternoon hours were seldom less than 75. The environmental conditions observed in these studies are typical for many, areas adjacent to the Gulf Coast of the United States and for tropical regions throughout the world. Providing comfortable environmental conditions for cows housed in area with hot, humid climates is difficult using only evaporative cooling and ventilation. Air-conditioning dairy housing is a possible alternative method, particularly for high value cows.25572773