Control of seagrass communities and sediment distribution by Callianassa (Crustacea, Thalassinidea) bioturbation

Shallow tropical lagoons at St. Croix, U.S. Virgin Islands were found to have high densities of the ghost shrimp Callianassa spp. The ecology of four species of Callianassa is discussed: C. acanthochirus, C. longiventris, C. rathbunae and C. quadracuta. The first two species capture and store in their burrows drifting detritus of seagrass and algae. The latter two species build volcano-shaped mounds of ejected sediment during feeding and burrowing. Massive quantities of sediment (up to 2.59 kg/m2/day) are funneled into subsurface galleries, gleaned for organic material and sorted. Fine grains (\u3c 1.4 mm diam.) are then pumped back up to the surface forming mounds. Coarse-grained material (≥ 1.4 mm) such as shell debris and coral fragments are not pumped back to the surface, but are stored in many deep chambers which extend \u3e 1.5 m below the sediment surface. In cross-section, cores from high Callianassa mound density regions show distinct alternating coarse and fine layers. This sedimentological evidence could be used as an indicator of Callianassa activity when interpreting the geological record from ancient tropical lagoonal environments.Maximum seagrass productivity and percent cover are negatively correlated (significant to p \u3c .01) with Callianassa mound density. Experimental and control transplants of the turtle grass Thalassia testudinum into regions of high (16/m2) and low (1/m2) Callianassa mound density produced a dramatic deterioration of Thalassia within 2-4 months in high density Callianassa areas. Ejected sediment either reduces available light for photosynthesis or physically smothers Thalassia, thereby eliminating it from regions of abundant Callianassa. Because seagrass communities have such intimate energetic ties to other nearby shallow-water and deep-sea communities, the negative influence of Callianassa on seagrass beds is suspected to have second and third order effects on other tropical communities as well

Women’s perceptions of pharmacist‐prescribed hormonal contraception

IntroductionUnintended pregnancy is a public health issue, with young women in their late teens and early 20s at highest risk. Multiple approaches to increasing contraception access have been implemented, including adoption of statewide pharmacist prescribing legislation in multiple states. Indiana does not currently have such legislation in place. The objective of this study was to identify how women at risk for unintended pregnancy in central Indiana perceive pharmacist prescribing of contraception.Study DesignQualitative, one‐on‐one semi‐structured interviews.MethodsPurposive, convenience sampling of eligible women 18 to 29‐years‐old who live in Indiana was used. Recruitment occurred via printed flyers placed in public locations that were not focused on health care, free classified online advertisements, and electronic flyers within Facebook social groups relevant to the study population. Interviews were conducted via telephone until thematic saturation was achieved. Participant demographics, baseline characteristics, current and past barriers to obtaining contraception, and perception of a pharmacist contraception prescribing model were collected. Interview transcripts were coded in an iterative manner with qualitative data analysis software (MAXQDA, Version 12) until consensus was achieved.ResultsFourteen women completed the study. Four primary themes emerged encompassing accessibility, communication, pharmacist attributes, and payment. Thirteen participants would personally utilize a pharmacist prescribing contraceptive service and all stated that this service would be beneficial for other women. Of those women expressing a preference (n = 7), a female pharmacist would be preferred for service delivery. Participants expressed concerns related to access by minors, skills and training of the pharmacist, and environment within the pharmacy.ConclusionsWomen in Indiana desire broader access to contraception. Efforts should be made at the individual pharmacist‐provider level and statewide to explore strategies to increase access. Resources should be allocated to the creation of protocols for pharmacist prescribing within Indiana and other states.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154257/1/jac51169.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154257/2/jac51169_am.pd

Recursive representation of the torus 1-point conformal block

The recursive relation for the 1-point conformal block on a torus is derived and used to prove the identities between conformal blocks recently conjectured by R. Poghossian. As an illustration of the efficiency of the recurrence method the modular invariance of the 1-point Liouville correlation function is numerically analyzed.Comment: 14 pages, 1 eps figure, misprints corrected and a reference adde

Peripheral, but not central, CB1 antagonism provides food intake-independent metabolic benefits in diet-induced obese rats.

OBJECTIVE Blockade of the CB1 receptor is one of the promising strategies for the treatment of obesity. Although antagonists suppress food intake and reduce body weight, the role of central versus peripheral CB1 activation on weight loss and related metabolic parameters remains to be elucidated. We therefore specifically assessed and compared the respective potential relevance of central nervous system (CNS) versus peripheral CB1 receptors in the regulation of energy homeostasis and lipid and glucose metabolism in diet-induced obese (DIO) rats. RESEARCH DESIGN AND METHODS Both lean and DIO rats were used for our experiments. The expression of key enzymes involved in lipid metabolism was measured by real-time PCR, and euglycemic-hyperinsulinemic clamps were used for insulin sensitivity and glucose metabolism studies. RESULTS Specific CNS-CB1 blockade decreased body weight and food intake but, independent of those effects, had no beneficial influence on peripheral lipid and glucose metabolism. Peripheral treatment with CB1 antagonist (Rimonabant) also reduced food intake and body weight but, in addition, independently triggered lipid mobilization pathways in white adipose tissue and cellular glucose uptake. Insulin sensitivity and skeletal muscle glucose uptake were enhanced, while hepatic glucose production was decreased during peripheral infusion of the CB1 antagonist. However, these effects depended on the antagonist-elicited reduction of food intake. CONCLUSIONS Several relevant metabolic processes appear to independently benefit from peripheral blockade of CB1, while CNS-CB1 blockade alone predominantly affects food intake and body weight

A mineralogical record of ocean change: decadal and centennial patterns in the California mussel

Ocean acidification, a product of increasing atmospheric carbon dioxide, may already have affected calcified organisms in the coastal zone, such as bivalves and other shellfish. Understanding species’ responses to climate change requires the context of long-term dynamics. This can be particularly difficult given the longevity of many important species in contrast with the relatively rapid onset of environmental changes. Here, we present a unique archival dataset of mussel shells from a locale with recent environmental monitoring and historical climate reconstructions. We compare shell structure and composition in modern mussels, mussels from the 1970s, and mussel shells dating back to 1000–2420 years BP. Shell mineralogy has changed dramatically over the past 15 years, despite evidence for consistent mineral structure in the California mussel, Mytilus californianus, over the prior 2500 years. We present evidence for increased disorder in the calcium carbonate shells of mussels and greater variability between individuals. These changes in the last decade contrast markedly from a background of consistent shell mineralogy for centuries. Our results use an archival record of natural specimens to provide centennial-scale context for altered minerology and variability in shell features as a response to acidification stress and illustrate the utility of long-term studies and archival records in global change ecology. Increased variability between individuals is an emerging pattern in climate change responses, which may equally expose the vulnerability of organisms and the potential of populations for resilience

THE CO LUM BIA RIVER GORGE THE STORY OF THE RIVER AND TH E ROCKS

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On "Dotsenko-Fateev" representation of the toric conformal blocks

We demonstrate that the recent ansatz of arXiv:1009.5553, inspired by the original remark due to R.Dijkgraaf and C.Vafa, reproduces the toric conformal blocks in the same sense that the spherical blocks are given by the integral representation of arXiv:1001.0563 with a peculiar choice of open integration contours for screening insertions. In other words, we provide some evidence that the toric conformal blocks are reproduced by appropriate beta-ensembles not only in the large-N limit, but also at finite N. The check is explicitly performed at the first two levels for the 1-point toric functions. Generalizations to higher genera are briefly discussed.Comment: 10 page

Clear Lake sediments: Anthropogenic changes in physical sedimentology and magnetic response

We analyzed the sedimentological characteristics and magnetic properties of cores from the three basins of Clear Lake, California, USA, to assess the depositional response to a series of land use changes that occurred in the watershed over the 20th century. Results indicate that distinct and abrupt shifts in particle size, magnetic concentration/mineralogy, and redox conditions occur concurrently with a variety of ecological and chemical changes in lake bed sediments. This coincidence of events occurred around 1927, a datum determined by an abrupt increase in total mercury (Hg) in Clear Lake cores and the known initiation of open-pit Hg mining at the Sulphur Bank Mercury Mine, confirmed by ²¹⁰Pb dating. Ages below the 1927 horizon were determined by accelerator mass spectrometry on ¹⁴C of coarse organic debris. Calculated sedimentation rates below the 1927 datum are ~1 mm/yr, whereas rates from 1927 to 2000 are up to an order of magnitude higher, with averages of ~3.5–19 mm/yr. In both the Oaks and Upper Arms, the post-1927 co-occurrence of abrupt shifts in magnetic signatures with color differences indicative of changing redox conditions is interpreted to reflect a more oxygenated diagenetic regime and rapid burial of sediment below the depth of sulfate diffusion. Post-1927 in the Oaks Arm, grain size exhibits a gradual coarsening-upward pattern that we attribute to the input of mechanically deposited waste rock related to open-pit mining activities at the mine. In contrast, grain size in the Upper Arm exhibits a gradational fining-upward after 1927 that we interpret as human-induced erosion of fine-grained soils and chemically weathered rocks of the Franciscan Assemblage by heavy earthmoving equipment associated with a road- and home-building boom, exacerbated by stream channel mining and wetlands destruction. The flux of fine-grained sediment into the Upper Arm increased the nutrient load to the lake, and that in turn catalyzed profuse cyanobacterial blooms through the 20th century. The resulting organic biomass, in combination with the increased inorganic sediment supply, contributed to the abrupt increase in sedimentation rate after 1927.KEYWORDS: Clear Lake, California, USA, particle size trends, ¹⁴C, paleolimnology, late Holocene, land use patterns, Sulphur Bank Mercury Mine, mercury, magnetic dissolutio