Effect of Delaware River flow on oysters in the natural seed beds of Delaware Bay

The Delaware River and Estuary flow through or border four states, New York,11 New Jersey \u27 Pennsylvania and Delaware. The use of their waters is intimately connected with the economies of each State. The use, however, is varied and different for each State. Any major change in the conditions of the river and estuary, while it may benefit one or more States, may also create conditions detrimental to others. The river from headwaters to Marcus Hook furnishes water used mostly.for domestic and industrial purposes. In the lower part of the river and estuary is the environment that supports the oyster, a natural resource utilized in an important food industry. The Interstate Commission on the Delaware River Basin and the New York Board of Water Supply are proposing to increase the utilization of the Delaware River water supply. Their plans, which include diversions, impoundments and releases, will result in diminution of the volume of fresh water flowing into the estuary. To what extent is this diversion likely to affect the welfare of the oysters by altering their environment? This paper is a report on a study conducted to answer that question

Ecological and physiological studies of the effect of sulfate pulp mill wastes on oysters in the York River, Virginia

This study of the York River and issues impacting the oyster fishery provides historical information on the river\u27s physical and chemical conditions (temperature, salinity, dissolved oxygen, turbidity, currents, etc.) effluent observations, history and data of the oyster fishery, oyster condition, biological and pathological work and experimental studies. The project studies were responsible for the establishment of a fisheries laboratory in Yorktown, Va. p. 59 - Funds for the York River investigations were made available in 1935 by a special allotment from the Public Works Administration. Continuation of the project was made possible by regular allotments by the Bureau of Fisheries and appropriations from the Commonwealth of Virginia through its Commission of Fisheries. In October 1935 a laboratory was established at Yorktown, Va., where a satisfactory supply of sea water was available for physiological studies\u27 on oysters. A boat suitable for the field observations was supplied by the Virginia Commission of Fisheries. Studies of the chemical nature of the pulp-mill effluents were carried on from July 1938 to July 1940 at laboratories made available by the College of William and Mary

Age-related neurochemical changes in the rhesus macaque inferior colliculus

Age-related hearing loss (ARHL) is marked by audiometric hearing deficits that propagate along the auditory pathway. Neurochemical changes as a function of aging have also been identified in neurons along the auditory pathway in both rodents and carnivores, however, very little is known about how these neurochemicals change in the non-human primate. To examine how these compensatory neurochemical changes relate to normal aging and audiometric sensitivity along the auditory pathway, we collected auditory brainstem responses (ABRs) and brain specimens from seven rhesus monkeys spanning in age from 15 to 35 years old, and examined the relationship between click evoked ABR thresholds and the ABR evoked pure tone average (PTA) and changes in the number of parvalbumin and NADPH-diaphorase positive cells in the auditory midbrain. We found that the number of parvalbumin positive cells in the central nucleus and the surrounding cortex regions of the inferior colliculus were strongly correlated with advancing age and ABR PTA. We also found that the numbers of NADPHd positive cells in these same regions were not associated with normal aging or changes in the ABR thresholds. These findings suggest that the auditory midbrain undergoes an up-regulation of parvalbumin expressing neurons with aging that is related to changes in the processing of frequencies across the audiometric range

Gas emissions, minerals, and tars associated with three coal fires, Powder River Basin, USA.

Ground-based surveys of three coal fires and airborne surveys of two of the fires were conducted near Sheridan, Wyoming. The fires occur in natural outcrops and in abandoned mines, all containing Paleocene-age subbituminous coals. Diffuse (carbon dioxide (CO(2)) only) and vent (CO(2), carbon monoxide (CO), methane, hydrogen sulfide (H(2)S), and elemental mercury) emission estimates were made for each of the fires. Additionally, gas samples were collected for volatile organic compound (VOC) analysis and showed a large range in variation between vents. The fires produce locally dangerous levels of CO, CO(2), H(2)S, and benzene, among other gases. At one fire in an abandoned coal mine, trends in gas and tar composition followed a change in topography. Total CO(2) fluxes for the fires from airborne, ground-based, and rate of fire advancement estimates ranged from 0.9 to 780mg/s/m(2) and are comparable to other coal fires worldwide. Samples of tar and coal-fire minerals collected from the mouth of vents provided insight into the behavior and formation of the coal fires

Post-neonatal Mortality, Morbidity, and Developmental Outcome after Ultrasound-Dated Preterm Birth in Rural Malawi: A Community-Based Cohort Study

Using data collected as a follow-up to a randomized trial, Melissa Gladstone and colleagues show that during the first two years of life, infants born preterm in southern Malawi are disadvantaged in terms of mortality, growth, and development

Combined inactivation of the Clostridium cellulolyticum lactate and malate dehydrogenase genes substantially increases ethanol yield from cellulose and switchgrass fermentations

<p>Abstract</p> <p>Background</p> <p>The model bacterium <it>Clostridium cellulolyticum </it>efficiently degrades crystalline cellulose and hemicellulose, using cellulosomes to degrade lignocellulosic biomass. Although it imports and ferments both pentose and hexose sugars to produce a mixture of ethanol, acetate, lactate, H₂and CO₂, the proportion of ethanol is low, which impedes its use in consolidated bioprocessing for biofuels production. Therefore genetic engineering will likely be required to improve the ethanol yield. Plasmid transformation, random mutagenesis and heterologous expression systems have previously been developed for <it>C. cellulolyticum</it>, but targeted mutagenesis has not been reported for this organism, hindering genetic engineering.</p> <p>Results</p> <p>The first targeted gene inactivation system was developed for <it>C. cellulolyticum</it>, based on a mobile group II intron originating from the <it>Lactococcus lactis </it>L1.LtrB intron. This markerless mutagenesis system was used to disrupt both the paralogous <smcaps>L</smcaps>-lactate dehydrogenase (<it>Ccel_2485; ldh</it>) and <smcaps>L</smcaps>-malate dehydrogenase (<it>Ccel_0137; mdh</it>) genes, distinguishing the overlapping substrate specificities of these enzymes. Both mutations were then combined in a single strain, resulting in a substantial shift in fermentation toward ethanol production. This double mutant produced 8.5-times more ethanol than wild-type cells growing on crystalline cellulose. Ethanol constituted 93% of the major fermentation products, corresponding to a molar ratio of ethanol to organic acids of 15, versus 0.18 in wild-type cells. During growth on acid-pretreated switchgrass, the double mutant also produced four times as much ethanol as wild-type cells. Detailed metabolomic analyses identified increased flux through the oxidative branch of the mutant's tricarboxylic acid pathway.</p> <p>Conclusions</p> <p>The efficient intron-based gene inactivation system produced the first non-random, targeted mutations in <it>C. cellulolyticum</it>. As a key component of the genetic toolbox for this bacterium, markerless targeted mutagenesis enables functional genomic research in <it>C</it>. <it>cellulolyticum </it>and rapid genetic engineering to significantly alter the mixture of fermentation products. The initial application of this system successfully engineered a strain with high ethanol productivity from cellobiose, cellulose and switchgrass.</p