Estimating Blue Carbon Stocks in Native and Non-Native Seagrass Beds of Jobos Bay, PR

Seagrasses are keystone species that support coastal biodiversity, but not all species of seagrasses provide the same ecosystem services. Although seagrasses occupy a small area of marine habitat, they provide many ecosystem services. They stabilize sediments, remove nutrients, provide habitat and food for diverse marine life, and promote carbon storage in sediments. Jobos Bay is the second largest estuary in Puerto Rico and contains salt marshes, mangroves, and seagrass beds. The native seagrass, Thalassia testudinum, is the most abundant seagrass in the bay; however, a seagrass species from the Indian Ocean, Halophila stipulacea, began invading in recent years. The impacts of H. stipulacea have not been well-studied, and it is not yet known if the invasive species is displacing the native species or growing only in areas that were previously non-vegetated. This study investigates the effect of the invasive species on carbon storage in Jobos Bay. If the native species contributes more detritus to the sediments but is being outcompeted by the invasive species, it will mean less organic matter is stored in the sediments as the invasion progresses. Between March 7-20, nine cores were extracted from four different habitat types: 1) a T. testudinum bed, 2) a H. stipulacea bed, 3) an unvegetated area, and 4) an area where an algal accumulation extirpated an H. stipulacea population. The cores were sliced in 1 cm increments. Slices were dried and combusted at 500 C to determine bulk density and organic carbon content. Patterns in the amount of carbon storage across the depths and habitat types will be compared. Estimates of carbon storage will help natural resource managers understand potential impacts of the invasive species on ecosystem services

Frequency-dependent seismic attenuation in shales: experimental results and theoretical analysis

Samples of shales from the Ordovician Bongabinni and Goldwyer source rock formations were recovered from the Canning Basin (Western Australia). Attenuation was experimentally measured on preserved plugs from these formations in the frequency range between 10−2 and 102 Hz. Samples cored with different orientations with respect to the sedimentary bedding were prepared and tested in their native saturated state and after drying in the oven at 105 °C for 24 hr to assess the effect of fluids and of the sediment anisotropy on attenuation. To aid the interpretation of the experimental results, the clay-rich samples were characterized in terms of mineralogy, water content, porosity, permeability and microstructure. The two shales have significantly different quality factors; and this is seen to be dependent on both the saturation state of the samples and the propagation direction of the oscillatory signal. The attenuation coefficient for compression/extension parallel to bedding is less than that vertical to bedding in both the preserved and partially dehydrated situations. No frequency dependency is observed in the preserved samples within the range of frequencies explored in this study. On the other hand partially saturated samples show peaks in attenuation at around 40 Hz when the stress perturbation is transmitted normal to the macroscopic bedding. The interpretation of the attenuation measurements in terms of well-established theoretical models is discussed in view of the physical characteristics and microstructure of the tested rock

Simon Says (Spring 2015)

In this issue: Library Instruction CSU Archives Launches Interactive Battle of Columbus Map A Student’s Perspective on Archival Processing Government Documents New Business Librarian and Government Documents Coordinator A First Look at the CSU ePress Library Forum Center of Online Learning Transformations Upcoming Library Events CSU Libraries Connectedhttps://csuepress.columbusstate.edu/library_newsletters/1016/thumbnail.jp

Non-breeding and nests without eggs in the Lesser Black-backed Gull.

Estimates of the number of breeding Lesser Black-backed Gulls Larus fuscus at the Tarnbrook Fell gullery, Lancashire, have been made from annual counts of nests since 1981. During all of these surveys, the mean percentage of nests which did not contain eggs has been remarkably constant from year to year (54%± 1.9%). A study of specific nests at the colony in 1992 showed that the great majority of these “empty” nests did not subsequently receive eggs. in 1993, a study of a sample of territory-holding gulls was made on a 0.41-ha study plot to investigate and to quantify the occurrence of empty nests. Of the 62 pairs that defended a territory and constructed a complete nest, 27% subsequently failed to produce eggs. These birds attended their territory as a pair significantly less frequently than pairs that produced clutches and achieved significantly fewer apparently successful mountings. Sixty percent of pairs constructed more than one nest, and 58% of all nests built received no eggs. The construction of empty nests was not found to be related to the density of nesting gulls. Since 1981, estimates of the number of gulls in the colony have been based on the assumption that one nest represents one pair of gulls. This has been shown not to be the case, and a correction multiplier of 0.61 must be applied to counts of nests at the colony to obtain an estimate of the number of breeding gulls

Atypical modulation of face-elicited saccades in autism spectrum disorder in a double-step saccade paradigm

Atypical development of face processing is a major characteristic in autism spectrum disorder (ASD), which could be due to atypical interactions between subcortical and cortical face processing. The current study investigated the saccade planning towards faces in ASD. Seventeen children with ASD and 17 typically developing (TD) children observed a pair of upright or inverted face configurations flashed sequentially in two different spatial positions. The reactive saccades of participants were recorded by eye-tracking. The results did not provide evidence of overall impairment of subcortical route in ASD, However, the upright, but not the inverted, face configuration modulated the frequency of vector sum saccades (an index of subcortical control) in TD, but not in ASD. The current results suggest that children with ASD do not have overall impairment of the subcortical route, but the subcortical route may not be specialized to face processing

Algae as nutritional and functional food sources: revisiting our understanding.

Global demand for macroalgal and microalgal foods is growing, and algae are increasingly being consumed for functional benefits beyond the traditional considerations of nutrition and health. There is substantial evidence for the health benefits of algal-derived food products, but there remain considerable challenges in quantifying these benefits, as well as possible adverse effects. First, there is a limited understanding of nutritional composition across algal species, geographical regions, and seasons, all of which can substantially affect their dietary value. The second issue is quantifying which fractions of algal foods are bioavailable to humans, and which factors influence how food constituents are released, ranging from food preparation through genetic differentiation in the gut microbiome. Third is understanding how algal nutritional and functional constituents interact in human metabolism. Superimposed considerations are the effects of harvesting, storage, and food processing techniques that can dramatically influence the potential nutritive value of algal-derived foods. We highlight this rapidly advancing area of algal science with a particular focus on the key research required to assess better the health benefits of an alga or algal product. There are rich opportunities for phycologists in this emerging field, requiring exciting new experimental and collaborative approaches.AGS & KEH thank the Biotechnology and Biological Sciences Research Council (BBSRC BB/1013164/1) of the UK for funding. The University of Dundee is a registered Scottish charity, No. SC015096. PP is supported by IDEALG in the frame of the stimuli program entitled “Investissements d’avenir, Biotechnologies-Bioressources” (ANR-10-BTBR-04-02). The open access fee was supported by NSF-OCE-1435021 (MLW), DIC project 1823-06 (MEC), Maine Sea Grant (NOAA) 5405971 (SHB), NSF #11A-1355457 to Maine EPSCoR at the University of Maine (SHB), and the listed funding to AGS and PP

Algae as nutritional and functional food sources: revisiting our understanding.

Global demand for macroalgal and microalgal foods is growing, and algae are increasingly being consumed for functional benefits beyond the traditional considerations of nutrition and health. There is substantial evidence for the health benefits of algal-derived food products, but there remain considerable challenges in quantifying these benefits, as well as possible adverse effects. First, there is a limited understanding of nutritional composition across algal species, geographical regions, and seasons, all of which can substantially affect their dietary value. The second issue is quantifying which fractions of algal foods are bioavailable to humans, and which factors influence how food constituents are released, ranging from food preparation through genetic differentiation in the gut microbiome. Third is understanding how algal nutritional and functional constituents interact in human metabolism. Superimposed considerations are the effects of harvesting, storage, and food processing techniques that can dramatically influence the potential nutritive value of algal-derived foods. We highlight this rapidly advancing area of algal science with a particular focus on the key research required to assess better the health benefits of an alga or algal product. There are rich opportunities for phycologists in this emerging field, requiring exciting new experimental and collaborative approaches.AGS & KEH thank the Biotechnology and Biological Sciences Research Council (BBSRC BB/1013164/1) of the UK for funding. The University of Dundee is a registered Scottish charity, No. SC015096. PP is supported by IDEALG in the frame of the stimuli program entitled “Investissements d’avenir, Biotechnologies-Bioressources” (ANR-10-BTBR-04-02). The open access fee was supported by NSF-OCE-1435021 (MLW), DIC project 1823-06 (MEC), Maine Sea Grant (NOAA) 5405971 (SHB), NSF #11A-1355457 to Maine EPSCoR at the University of Maine (SHB), and the listed funding to AGS and PP

Scientific evidence for the identification of an Aboriginal massacre at the Sturt Creek sites on the Kimberley frontier of north-western Australia

© 2017 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (Sept 2017) in accordance with the publisher’s archiving policyArchival research into episodes of frontier violence in the Kimberley region of Western Australia indicate that the bodies of Aboriginal victims of massacres were frequently incinerated following the event. This paper presents the results of a scientific investigation of a reported massacre at Sturt Creek where burnt bone fragments were identified in two adjacent sites and documents the archaeological signatures associated with the sites. The methodology used to undertake the project brought together three systems of knowledge: the oral testimonies of the descent group originating from a sole adult survivor of the massacre; archival, historical and scientific research. An archaeological survey defined the two distinct sites containing hundreds of fragile bone fragments; a third site was found to be highly disturbed. Scientific investigations included macroscopic and microscopic examination of selected bone fragments by an anatomical pathologist and a zooarchaeologist and X-ray diffraction analysis of sixteen bone fragments. The anatomical pathologist and zooarchaeologist undertook macroscopic and microscopic examinations of selected bone samples to identify morphological evidence for human origin. It was concluded that three bone fragments examined may have been human, and two of the fragments may have been from the vault of a skull. It was concluded that the likelihood of them being human would be strengthened if it was found that the three samples had been subjected to high temperatures. X-ray diffraction analysis of 16 bone fragments provided this evidence. All fragments showed sharp hydroxylapatite peaks (crystallite sizes 9882 nm and 597 nm respectively) and all had been subjected to extreme temperatures of either 600 °C for more than 80 h, 650 °C for more than 20 h, 700 °C for more than 4 h or 800 °C for more than 1 h. XRD analyses were also done on bone samples collected from three cooking hearths at three different archaeological sites. It was found that two of the three samples had been exposed to substantially lower temperatures for a short time period. It was concluded that there was strong pathological and archaeological evidence that the bone fragments were human in origin, but that the evidence was not conclusive. This research also identified archaeological signatures for the identification of massacre sites in similar Australian environments and circumstances

Novel insights into axon diameter and myelin content in late childhood and adolescence

White matter microstructural development in late childhood and adolescence is driven predominantly by increasing axon density and myelin thickness. Ex vivo studies suggest that the increase in axon diameter drives developmental increases in axon density observed with pubertal onset. In this cross-sectional study, 50 typically developing participants aged 8–18 years were scanned using an ultra-strong gradient magnetic resonance imaging scanner. Microstructural properties, including apparent axon diameter (da) ⁠, myelin content, and g-ratio, were estimated in regions of the corpus callosum. We observed age-related differences in da ⁠, myelin content, and g-ratio. In early puberty, males had larger da in the splenium and lower myelin content in the genu and body of the corpus callosum, compared with females. Overall, this work provides novel insights into developmental, pubertal, and cognitive correlates of individual differences in apparent axon diameter and myelin content in the developing human brain