MINERAL PARAGENESIS OF A PARTIALLY SERPENTINIZED DUNITE IN EAST DOVER, VERMONT

Ultramafic rocks exposed on the Earth’s surface offer a rare opportunity to directly study the petrology of the upper mantle. The Appalachian Mountains of Vermont contain variably serpentinized ultramafic rocks that mark the suture zone for the Ordovician Taconic Orogeny. In southern Vermont, the serpentinized ultramafic rocks were subsequently metamorphosed to amphibolite facies during the Devonian Acadian Orogeny. Key localities of partially serpentinized ultramafic rocks and their surrounding lithologies in East Dover, Vermont were sampled to better understand the mineral petrogenesis and metamorphic history of the East Dover meta-dunite. This thesis documents the first occurrence of podiform chromitite, platinum group minerals, arsenic minerals, and metamorphic olivine in ultramafic rocks from the Vermont Appalachian Mountains. Rare chromitite occurs as pods within the dunite and is highly brecciated. Cr# (Cr/Cr+Al) is extremely high in podiform chromitite (0.7 - 0.9) suggesting that it formed via fluid/melt-rock interaction during partial melting of upper mantle peridotite in a supra-subduction zone setting. Rare inclusions of platinum group mineral alloys were found as inclusions in podiform chromitite. Many of these platinum group minerals contained arsenic. Small nickel arsenide minerals are common in serpentinized ultramafic rocks. Whole rock geochemical analyses (XRF) indicate much higher concentrations of arsenic in the more serpentinized samples, suggesting that arsenic was introduced into the ultramafic rocks during serpentinization. In the meta-dunite, the composition of olivine ranges from Fo92 in spinel inclusions to Fo96 in neoblastic olivine. Olivine neoblasts likely formed from serpentine dehydration during peak metamorphic temperatures associated with regional metamorphism during the Devonian Acadian Orogeny. Decussate amphibolite and late stage coarse acicular serpentine likely formed as the region slowly cooled following Devonian orogenesis. Recent near-surface lateritic weathering produced local areas of nickel mineralization. Chromite, platinum group minerals, and nickel minerals do not appear to occur in quantities sufficient for exploitation from the East Dover area. Our findings illustrate the need for an investigation into the mineralogy of other ultramafic bodies in Vermont to better understand the relative timing of mineral petrogenesis and the societal implications of the presence of arsenic bearing minerals in ultramafic rocks

Chapter 9: Aquatic Macroinvertebrates, Section A: Aquatic Macroinvertebrates (Exclusive of Mosquitoes)

Final Report. Excerpt (Chapter 9, Section A) from The Des Plaines River Wetlands Demonstration Project, Volume II, Baseline Survey, edited by Donald L. Hey and Nancy S. PhilippiReport issued on: October 1985INHS Technical Report prepared for Wetlands Research, Inc

Testing Transparency

In modern democracies, governmental transparency is thought to have great value. When it comes to addressing administrative corruption and mismanagement, many would agree with Justice Brandeis’s observation that sunlight is the best disinfectant. Beyond this, many credit transparency with enabling meaningful citizen participation. But even though transparency appears highly correlated with successful governance in developed democracies, assumptions about administrative transparency have remained empirically untested. Testing effects of transparency would prove particularly helpful in developing democracies where transparency norms have not taken hold or only have done so slowly. In these contexts, does administrative transparency really create the sorts of benefits attributed to it? Transparency might grease the gears of developed democracies, but what good is grease when many of the gears seem to be broken or missing entirely? This Article presents empirical results from a first-of-its-kind field study that tested two major promises of administrative transparency in a developing democracy: that transparency increases public participation in government affairs and that it increases government accountability. To test these hypotheses, we used two randomized controlled trials. Surprisingly, we found transparency had no significant effect in almost any of our quantitative measurements, although our qualitative results suggested that when transparency interventions exposed corruption, some limited oversight could result. Our findings are particularly significant for developing democracies and show, at least in this context, that Justice Brandeis may have oversold the cleansing effects of transparency. A few rays of transparency shining light on government action do not disinfect the system and cure government corruption and mismanagement. Once corruption and mismanagement are identified, it takes effective government institutions and action from civil society to successfully act as a disinfectant

New Records of the Eastern Red Bat, Lasiurus borealis, from Cypress Hills Provincial Park, Saskatchewan: A Response to Climate Change?

During the summer of 2001 we captured two Eastern Red Bats (Lasiurus borealis) in Cypress Hills Provincial Park, Saskatchewan. A possible explanation for this range extension is a warming trend since 1965 documented for the area

Optical control of mammalian endogenous transcription and epigenetic states

The dynamic nature of gene expression enables cellular programming, homeostasis and environmental adaptation in living systems. Dissection of causal gene functions in cellular and organismal processes therefore necessitates approaches that enable spatially and temporally precise modulation of gene expression. Recently, a variety of microbial and plant-derived light-sensitive proteins have been engineered as optogenetic actuators, enabling high-precision spatiotemporal control of many cellular functions. However, versatile and robust technologies that enable optical modulation of transcription in the mammalian endogenous genome remain elusive. Here we describe the development of light-inducible transcriptional effectors (LITEs), an optogenetic two-hybrid system integrating the customizable TALE DNA-binding domain with the light-sensitive cryptochrome 2 protein and its interacting partner CIB1 from Arabidopsis thaliana. LITEs do not require additional exogenous chemical cofactors, are easily customized to target many endogenous genomic loci, and can be activated within minutes with reversibility. LITEs can be packaged into viral vectors and genetically targeted to probe specific cell populations. We have applied this system in primary mouse neurons, as well as in the brain of freely behaving mice in vivo to mediate reversible modulation of mammalian endogenous gene expression as well as targeted epigenetic chromatin modifications. We explore the modularity of the LITE approach through the development of CRISPR/Cas9 transcriptional effectors in either constitutively active or light-inducible contexts. The LITE system establishes a novel mode of optogenetic control of endogenous cellular processes and enables direct testing of the causal roles of genetic and epigenetic regulation in normal biological processes and disease states.Engineering and Applied Science

Using New Selection Tools

The goal of most beef production systems is to increase or at least maintain profitability. Producers can attempt to increase profitability in a variety of ways that might include reducing feed costs, changing their marketing program, or perhaps by changing the performance of their herd through genetic improvement. Focusing on this latter option, there are two primary genetic tools available: selection and mating where selection refers to the selection of breeding animals and mating includes which females are mated to which bulls, for example, crossbreeding systems. This paper focuses on the former, the selection of the appropriate animals for a production system with the goal to improve profitability. The best tool available for making selection decisions is expected progeny differences (EPD). Over the years the number of EPD available to guide producers in making selection decisions has grown from 5 to over 15 in most cases. Simply put, the amount of information that the breeder must sift through to try to make a good selection decision has become overwhelming. The producer must determine which EPD have the greatest influence on their income and their expenses, and by how much—a daunting task. Historically this task has depended on the “intuition” and experience of the breeder. For instance, they know that selection for heavier weaning weight will increase the weight of calves sold at weaning, but that blind selection for weaning weight will also increase calving difficulty and if replacements are kept, likely increase cow size and feed costs. Breeders have been performing a balancing act with little concrete information on how important each of those traits is to their profitability. Fortunately, there are several tools that have recently become available to ease the process of combining the costs and the revenues of beef production with EPD to make selection decisions that will produce progeny which are more profitable

Flexibility in Animal Signals Facilitates Adaptation to Rapidly Changing Environments

Charles Darwin posited that secondary sexual characteristics result from competition to attract mates. In male songbirds, specialized vocalizations represent secondary sexual characteristics of particular importance because females prefer songs at specific frequencies, amplitudes, and duration. For birds living in human-dominated landscapes, historic selection for song characteristics that convey fitness may compete with novel selective pressures from anthropogenic noise. Here we show that black-capped chickadees (Poecile atricapillus) use shorter, higher-frequency songs when traffic noise is high, and longer, lower-frequency songs when noise abates. We suggest that chickadees balance opposing selective pressures by use low-frequency songs to preserve vocal characteristics of dominance that repel competitors and attract females, and high frequency songs to increase song transmission when their environment is noisy. The remarkable vocal flexibility exhibited by chickadees may be one reason that they thrive in urban environments, and such flexibility may also support subsequent genetic adaptation to an increasingly urbanized world

Behavioural ecology and thermal physiology of Australian Owlet-Nightjars ('Aegotheles cristatus')

The Australian owlet-nightjar ('Aegothelidae cristatus') is a sedentary, nocturnal, avian insectivore that uses a variety of adaptations to balance its energy budget. This has enabled this species to successfully inhabit diverse habitats throughout Australia. Owlet-nightjars are Caprimulgiformes, a group that typically have low metabolic rates and are capable of entering torpor to conserve energy. However, unlike many species of Caprimulgiformes, owlet-nightjars do not migrate and therefore must cope metabolically and behaviourally with seasonal variations in ambient temperature (Ta) and food resources. They are also unique amongst the Caprimulgiformes in that they are obligate cavity users year-round. I studied the behavioural and physiological qualities that enable this species to subsist in two dissimilar habitats, the semi-arid desert of central Australia and the comparatively cold, mesic, eucalypt woodlands atop the Northern Tablelands of NSW. I used radiotelemetry to locate diurnal roost sites, to track birds to determine home range, and to quantify body temperature (Tb) fluctuations in relation to roost and ambient thermal conditions. I compared characteristics of cavity roosts with randomly selected unoccupied cavities and used an information theoretic approach to assess variables which may be important for roost selection. Faecal samples collected from birds and cavity roosts at both locations were used to compare the diet and inferred foraging tactics between the two habitats in relation to arthropod availability. Finally, I measured the metabolic rate and thermal conductance of individual birds in the laboratory during both summer and winter using open-flow respirometry in the laboratory