bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrogeology of a Portion of the Sand Hills and Ogallala Aquifer, South Dakota and Nebraska
Authors: Rahn Perry H. , Paul Howard A.
Published: July 2006

The Pliocene Ogallala Formation and the Quaternary Sand Hills Formation cover an extensive area in the north‐central prairie states. The area studied in this investigation includes only that portion between the Little White River, South Dakota, and the Niobrara River, Nebraska, where the saturated thickness is about 100 feet and a five‐day aquifer test showed that the coefficient of permeability is 439 gpd/ft2. The water has a total dissolved solids content of only 90 ppm. An average of 18 inches of precipitation falls on this arid country annually, and the average annual recharge to these permeable deposits is calculated at 2 to 3 inches.

Little ground‐water development has occurred in the area to date, but the aquifer has considerable potential. The aquifer is exceptionally permeable, close to the surface and easy to drill, and has exceptionally good recharge and good quality water. Data on recharge rates and theoretical distance‐drawdown curves support the conclusion that irrigation of more than 1 quarter‐section for every 2 sections of land would cause a depletion of the aquifer.
Water Monitoring – Jim Bridger Project – Sweetwater County, Wyominga
Authors: Florquist Bruce A. , Hilbelink Paul A.
Published: July 2006

Beginning in February of 1974 and continuing to and through the start‐up of the first generating unit at the Jim Bridger Power Plant on August 8, 1974, the authors were drilling monitoring holes, collecting water samples and evaluating water quality and ground‐water levels at the project. During the course of this evaluation, considerable data was developed. Some unique and unusual problems were encountered and some of the results are interesting.

As of this writing, there are over 25 water quality stations being monitored. Most of these stations are monitoring wells drilled into Tertiary or Cretaceous sedimentary rocks although some monitoring wells are drilled into recent stream alluvium. Also, there are surface‐water monitoring sites on two major streams, the freshwater surge pond and the evaporation ponds that receive the blow‐down water from the power plants' cooling towers.

These waters were analyzed for at least 21 minerals and/or ions as well as pH, dissolved oxygen, turbidity, temperature and such exotics as phenols, hydrazine and ammonia.

The indigenous water quality of the area is poor with total dissolved solids ranging to 15,000 mg/l and pH values from 7.3 to 12.3. pH values were found to vary as much as four points between two monitoring stations fifteen feet apart. This water quality is expected to be improved by the importation of relatively high‐quality water from the Green River via a 41‐mile pipeline.

Graphs have been prepared showing some of the concentrations of the more important minerals and their relationship to human, cattle, sheep, crop and boiler tolerances. A water suitability chart also shows how the water quality in the various geologic units as well as the surface water relates to various limitations of water use.

Seven of the nine toxic substances cited by the Public Health Service standards were analyzed. Of these, silver, arsenic, cadmium, hexavalent chromium and cyanide were not present in objectionable quantities. Lead, however, was excessive during some months at all well sites and two surface sites on a stream that parallels an interstate highway for more than 6 miles.

The water quality was found to have a definite relationship to the geology. Similarly, the geologic conditions are expected to be the governing factor in the rate and direction of flow of subsurface water. This factor will be of major significance when the blow‐down water in design concentrations of 30,500 mg/l TDS is discharged into the evaporation pond during the projected thirty‐five‐year life of the project.
Change in Drawdown Caused by Enlarging a Well in a Dolomite Aquifer
Authors: Norris Stanley E.
Published: July 2006

Step‐drawdown tests of a well in a dolomite aquifer in north‐central Ohio, before and after it was enlarged from 10 to 12 inches (250 to 300 millimetres) in diameter, indicate changes in the well‐loss constant, the exponent for turbulent flow, and the formation loss factor. The calculated difference in drawdown resulting from enlarging the well is of little practical importance at rates of 300 to 500 gallons per minute (19 to 31 litres per second), the range of rates at which the well is expected to be pumped, but for higher rates the decrease in drawdown and consequent reduction in power costs could be significant. For a pumping rate of 1,500 gallons per minute (95 litres per second), the decrease in drawdown would be 20.4 feet (6.2 metres).
Ground‐Water and Surface‐Water Relationships in the Glacial Province of Northern Wisconsin—Snake Lake
Authors: Jaquet Neil G.
Published: July 2006

Lake rejuvenation efforts in the Upper Midwest are important to the area's economic dependence on high‐quality lakes for tourism. In developing eutrophication studies for lakes in this area, it is essential to determine the thickness of aquifer communicating with the lake, as a preliminary to calculation of the lake flushing rate. The thickness of communicating aquifer is particularly critical for lakes fed primarily by ground‐water recharge, e.g. Snake Lake, Wisconsin. Through use of observation wells and chloride tracer analysis, effective aquifer thickness at Snake Lake is determined to be 30 to 50 feet. However, the local flow systems are additionally found to be highly variable through the progression of seasons. The possible effect of such dynamic seasonal fluctuations on the local flow system should be considered in eutrophication studies to avoid possible improper siting of underground chemical and/or petroleum storage facilities and septic tanks in glacial deposit environments.
Fibonacci Search for High‐Yield Well Sites
Authors: Helweg Otto J.
Published: July 2006

In areas where the bedrock is irregular, depressions in the bedrock formation can yield significantly higher amounts of water because the aquifer has a greater saturated thickness. Finding these areas by drilling test holes is a common practice but one that can be conducted more economically if an efficient search procedure is utilized. This paper describes such a technique called the Fibonacci Search and shows that it can save thousands of dollars in the cost of drilling test holes when compared to “brute‐force” methods.
The Lycoming County, Pennsylvania, Sanitary Landfill: State‐of‐the‐Art in Ground‐Water Protectiona
Authors: Giddings M. Todd
Published: July 2006

A 120‐acre sanitary landfill site is being developed in north‐central Pennsylvania to serve a six‐county area. The design of the site will prevent ground‐water contamination by leachate from the refuse through the use of a 20‐mil (.5 mm) PVC plastic liner which will lie between two protective layers of sand containing drainpipe networks.

Sampling of the composite ground‐water flow from the underdrainpipe network in the sand blanket under the liner will provide sensitive monitoring of the liner performance. In the unlikely event of a leak, the pipe draining that area would be diverted to the leachate treatment facility, thus providing a backup leachate collection system. A thick (15 to 75 feet, 4.6 to 22.9 metres) glacial till deposit is present at the site and confines ground‐water flow within the underlying shale bedrock. The low permeability of the till and the artesian head within the bedrock flow system provide additional protection against ground‐water contamination.

Operation of the site will be by the area‐fill method; the refuse will be deposited in 8‐foot (2.4‐metre) lifts up to a maximum height of 120 feet (36.6 metres). Based on an initial refuse deposit rate of 400 tons (363 metric tons) per day, the site is expected to have a 20‐year life at a disposal cost of approximately $5.00 per ton.

Local residents who felt this project posed a severe threat to their wells strenuously opposed the project and appealed the State permit. The Pennsylvania Environmental Hearing Board upheld the permit; the decision was appealed to Commonwealth Court and was upheld. Residents remain unconvinced the design and site conditions will provide adequate protection and have petitioned the Pennsylvania Supreme Court to consider another appeal.

A baseline water‐quality monitoring program has been undertaken to establish on‐site conditions and a private‐well sampling program will begin before the landfill is in operation. Till and bedrock monitoring wells at the site will be used to evaluate the performance of this landfill; analysis of the nearby private wells will be provided to the owners to demonstrate confidence in the design and the satisfactory operation of the ground‐water protection measures.
Quantifying the Natural Flushout of Alluvial Aquifersa
Authors: Fryberger John S. , Bellis William H.
Published: July 2006

A plume of contaminated water may extend downstream for several miles in an alluvial aquifer. Hydrologic forces acting on the aquifer generally tend to dilute the contaminant downstream from the source. After the pollution has been stopped, how rapidly will these hydrologic forces flush out the contaminant? The answer to this question may be calculated by using the mass‐balance equation herein developed.

This mass‐balance mathematical model incorporates all the hydrologic forces acting on the alluvial aquifer that affect the concentration of the contaminant. Methods are presented to define and quantify each of the hydrologic forces. These forces include (1) present quantity and quality (with respect to contaminant) of water in the alluvium and the change in the quality downstream, (2) quantity and quality of ground‐water inflow, (3) quantity and quality of flood inflow, (4) quantity and quality of base flow, (5) quantity of recharge from precipitation, and (6) quantity of loss from evapotranspiration.

The equation is first balanced to agree with past conditions and observed field data and is then used to predict future quality changes after the pollution is stopped.

The method is applicable primarily to situations in which the pollution has been taking place over a long period of time and the water quality in the alluvium has reached equilibrium at any given point. Modifications may be possible to permit use of the general approach to short‐term or slug‐type pollution events.
Land Disposal of Hazardous Wastes: An Example from Hopewell, Virginiaa
Authors: Walz D. H. , Chestnut K. T.
Published: July 2006

In early September 1975 a Technical Committee was established by the Virginia State Department of Health to clean up and dispose of a manufacturing plant which had produced the pesticide Kepone, in Hopewell, Virginia. The Committee recommended that the hazardous wastes be buried in a virgin section of the new City of Hopewell landfill. The disposal pit was designed to encapsulate the wastes in clay and plastic. The project was completed in early March 1976. The disposal site is monitored by the Virginia State Water Control Board via an observation well and an underdrain system.
Utilizing a Digital Model to Determine the Hydraulic Properties of a Layered Aquifer
Authors: Land Larry F.
Published: July 2006

The hydraulic characteristics of a layered ground‐water system are determined by a modified digital model. Its use provides information on the hydraulic conductivity and storage coefficient of a stratum and on the transmissivity and storage coefficient of the ground‐water system as a whole. These characteristics are determined by trial‐and‐error test runs until the calculated drawdowns reasonably match drawdown data from observation wells which are open to the artesian aquifer and to the confining beds above or below. An aquifer test of a layered ground‐water system in Palm Beach County, Florida shows that the transmissivity of the ground‐water system as a whole is 50 percent higher than just the transmissivity of the major water‐bearing zone in this system.
Toxic Metals in Ground Water of the Front Range, Colorado
Authors: Klusman Ronald W. , Edwards Kenneth W.
Published: July 2006

A study of toxic trace metal distribution in ground waters of the Front Range mineral belt, Colorado and adjacent areas was performed in order to determine the relationship of water quality to mineralization and the magnitude of potential health effects. A total of 149 samples were collected and analyzed for arsenic, cadmium, copper, iron, lead, manganese, mercury, silver and zinc. Field determinations of pH, Eh, and specific conductance were also made.

The trace element data exhibited a lognormal distribution and are described utilizing the geometric mean and geometric deviation. Four populations were recognized in the samples: (1) samples in the mineral belt with plumbing contamination; (2) samples in the mineral belt without plumbing contamination, (3) samples outside the mineral belt with plumbing contamination, and (4) samples outside the mineral belt without plumbing contamination. Differences in these populations for several elements are observed utilizing the t test.

Utilizing the observed data distributions, geochemical abundance estimates are made for the four recognized populations. The data distributions are corrected for analytical error, corrected for determinations below the detection limit and expressed as a predicted central 95% range for each element in each population. The corrected geometric mean, corrected geometric deviation, along with the U.S. Public Health Service limit for each element determined are used to determine the probability of ground water exceeding the specified limit for each constituent. Ground waters in the mineral belt are estimated to exceed the U.S. Public Health Service limit in 14% of the samples for Cd, 1% for Cu, 51% for Fe, 74% for Mn, 2% for Hg, and 9% for Zn. Ground waters outside the mineral belt have a similar probability of exceeding the limit for Hg and lesser probabilities for all other elements.
Two‐Dimensional Searches for High‐Yield Well Sites
Authors: Türk Göksel
Published: July 2006

In areas where bedrock is irregular, greater saturation thickness of aquifer will associate with the depression in the bedrock formation. Wells located upon these depressions can yield significantly higher amounts of water. Hence, finding the bottom of depression in the area will be of interest, and this can be facilitated by drilling test holes. These test holes can be drilled at the nodes of a regular grid; however, more efficient search techniques are available. Fibonacci search in one dimension has recently been proposed and potential saving in drilling cost demonstrated. But the problem is essentially two‐dimensional in nature. This paper describes some two‐dimensional search procedures for this purpose and shows that potential saving in drilling cost can be dramatic.
Disposal of Salt Water During Well Construction: Problems and Solutionsa
Authors: Pitt William A. J. , Meyer Frederick W. , Hull John E.
Published: July 2006

The recent interest in the disposal of treated sewage effluent by deep‐well injection into salt‐water‐filled aquifers has increased the need for proper disposal of salt water as more wells are drilled and tested each year.

The effects on an unconfined aquifer of the improper disposal of salt water associated with the construction of three wells in southeastern Florida emphasize this need. In two of the wells provisions to prevent and detect salt‐water contamination of the unconfined aquifer were practically nonexistent, and in one well extensive provisions were made. Of the three drilling sites the one with proper provision for detection presented no serious problem, as the ground water contaminated by the salt water was easily located and removed. The provisions consisted of drilling a brine‐injection well to dispose of salt water discharged in drilling and testing operations, using a closed drilling circulation system to reduce spillage, installing shallow observation wells to map the extent and depth of any salt‐water contamination of the shallow aquifer, and installing a dewatering system to remove contaminated ground water.
Storage of Treated Sewage Effluent and Storm Water in a Saline Aquifer, Pinellas Peninsula, Florida
Authors: Rosenshein J. S. , Hickey J. J.
Published: July 2006

The Pinellas Peninsula, an area of 750 square kilometres (290 square miles) in coastal west‐central Florida, is a small hydrogeologic replica of Florida. Most of the Peninsula's water supply is imported from well fields as much as 65 kilometres (40 miles) inland. Stresses on the hydrologic environment of the Peninsula and on adjacent water bodies, resulting from intensive water‐resources development and waste discharge, have resulted in marked interest in subsurface storage of waste water (treated effluent and untreated storm water) and in future retrieval of the stored water for nonpotable use. If subsurface storage is approved by regulatory agencies, as much as 265 megalitres per day (70 million gallons a day) of waste water could be stored underground within a few years, and more than 565 megalitres per day (150 million gallons a day) could be stored in about 25 years. This storage would constitute a large resource of nearly fresh water in the saline aquifers underlying about 520 square kilometres (200 square miles) of the Peninsula.

The upper 1,060 metres (3,480 feet) of the rock column underlying four test sites on the Pinellas Peninsula have been explored. The rocks consist chiefly of limestone and dolomite. Three moderately to highly transmissive zones, separated by leaky confining beds, (low permeability limestone) from about 225 to 380 metres (740 to 1,250 feet) below mean sea level, have been identified in the lower part of the Floridan aquifer in the Avon Park Limestone. Results of withdrawal and injection tests in Pinellas County indicate that the middle transmissive zone has the highest estimated transmissivity‐about 10 times other reported values. The chloride concentration of water in this zone, as well as in the two other transmissive zones in the Avon Park Limestone in Pinellas Peninsula, is about 19,000 milligrams per litre. If subsurface storage is approved and implemented, this middle zone probably would be used for storage of the waste water and the zone would become the most extensively used in Florida for this purpose.
Estimating Transmissivity and Storage Coefficient from Abstraction Well Data
Authors: Rushton K. R.
Published: July 2006

A numerical model for analyzing pumping tests is used to estimate the transmissivity and the storage coefficient from abstraction well‐water levels measured during both the abstraction and recovery phases. The technique is applied to a practical test. In addition, an ideal test is devised and the technique is used to give satisfactory estimates of the parameters.
Maine's Ground‐Water Situation
Authors: Caswell W. Bradford
Published: July 2006

Maine's population is highly dependent upon ground‐water supplies that are obtained from low‐yield, fractured, crystalline bedrock aquifers. Although most domestic bedrock wells yield less than 10 gallons per minute (gpm), there are a number of bedrock wells that yield 10 to 300 gpm. Many of these wells are drilled in the vicinity of major faults. Some bedrock wells intersect fractures that open directly to the land surface, which causes them to be particularly susceptible to contamination. The glacial cover is generally less than 20 feet thick and is not considered a significant aquifer in most places. Sand and gravel aquifers are scattered across the State, but in total cover only about 15% of the surface. Coastal residents commonly obtain water from the fractured rock aquifer. Salt‐water intrusion occurs, but in most places appears to be caused by the geometry of the rock fractures, rather than by excessive pumping. Ground‐water quality is generally good because of low solubility of the crystalline rocks, and because of dilution by plentiful rainfall.
Electric Analog Model Study of Aquifer in Krishni‐Hindon Interstream Region, U.P., India
Authors: Gupta C. P. , Thangarajan M. , Rao V.V.S. Gurunadha
Published: July 2006

Overexploitation of ground water in Krishni‐Hindon interstream region (Lat. 29°05′N‐29°29′N and Long. 77°19′E‐77°32′E) in Uttar Pradesh, India, prompted us to carry out aquifer modeling studies. The area lies in Gangetic alluvial plain. The interconnections in the phreatic aquifer and the lower semiconfined aquifer led to the assumption of a single‐story aquifer for which an R‐C analog model was constructed.

The input‐output quantities in the model have been simulated using current/voltage generators and current sinks which are appropriately programmed in time‐domain with the help of wave‐form synthesizers for a realistic representation of the field system.

The model study shows that the aquifer can sustain the present output rate of 200 mcm/year without much damage to the ground‐water regime. In another scheme, an annual increase of 5% in exploitation rate, shows deleterious effects on the aquifer. Decreased rainfall/ droughts would worsen the situation.

The influence of hydraulic connectivity between the aquifer and the Krishni‐Hindon river system is quite significant. If the present exploitation rate were to continue for 20 years, the annual inflow to the aquifer from rivers is estimated to increase by about 36.0 mem.

More hydrogeological data is required for further validation and refinement of the model.
MACROECONOMIC UNCERTAINTY AND AGGREGATE PRIVATE INVESTMENT IN SOUTH AFRICA
Authors: Kumo Wolassa L.
Published: July 2006

This paper investigates the effects of time varying uncertainty on aggregate private fixed investment in South Africa. The GARCH generated measures of volatility of selected macroeconomic variables indicating five measures of uncertainty are used in the analysis. These are output growth uncertainty, uncertainty about changes in the real effective exchange rate, uncertainty about changes in the real interest rate, producer inflation uncertainty, and terms of trade uncertainty. The results of the estimation by an empirical ECM model of conventional investment determinants controlling for the effects of uncertainty indicated that, over all, time varying macroeconomic uncertainty significantly reduces private fixed investment.
INTEREST RATE PASS‐THROUGH IN THE COMMON MONETARY AREA OF THE SACU COUNTRIES
Authors: Sander Harald , Kleimeier Stefanie
Published: July 2006

We investigate the interest rate pass‐through in the four Common Monetary Area (CMA) countries of the South African Customs Union (SACU). We employ an empirical pass‐through model that allows for thresholds, asymmetric adjustment, and structural changes. We show that CMA bank lending markets exhibit quite some degree of homogenization as the pass‐through is often fast and complete. Deposit markets are somewhat more heterogeneous by showing differing degrees of interest rate stickiness and asymmetric adjustment. Policy makers should therefore be concerned about imperfect competition which may be at the heart of the remaining cross‐country differences in monetary transmission in the CMA.
A New Wire-Driven Three Degree-of-Freedom Parallel Manipulator
Authors: Ning KeJun , Zhao MingYang , Liu Jie
Published: July 2006

This paper puts forward a new wire-driven parallel manipulator. The mechanism and implementation scheme are presented in detail. Some theoretical and simulation results are introduced briefly. A prototype system, named HN-4MX, has been completed. Some experiments testify to the feasibility of the new wire-driven system. This manipulator has some advantages, which can be useful in industrial field. We predict its industrial application in this paper.
Preform Design of Powder Metallurgy Turbine Disks Using Equi-Potential Line Method
Authors: Liu Yuhong , Li Fuguo , Wang Shuxin , Hu S. Jack
Published: July 2006

In a material hot forging process, rational preform design not only ensures that metal flows properly in die cavity and that final products have excellent quality, but also reduces tooling cost. In the present work, it is proved in theory that the differential equation of electric potential (∇2ϕ=0) in the electrostatic field is similar to the differential equations of velocity potential function (∇2φ=0) and velocity stream function (∇2ψ=0) in velocity field during the material forming process, with all three represented in the form of the Laplace equation. Moreover, the material flow in the plastic stage and the energy in electrostatic field all meet the least-energy principle. Therefore, according to the similarity criteria, an equi-potential line (EPL) method is proposed for the design of the preform shape in material hot forging. Different voltages are applied to the billet shape and the final product shape to generate a proper electrostatic field. One optimal equi-potential line is selected among the innumerable equi-potential lines as the basic shape of the preform shape and is processed into the preform shape following a three-step procedure. The preform design by the EPL method is compared with that by the traditional industrial method. The results show that the proposed method for preform design is feasible and reliable for practical applications.
The Interferon-Inducible GTPases
Authors: Martens Sascha , Howard Jonathan
Published: July 2006

Mammalian cells respond to interferons (IFNs) secreted during infection by the transcriptional upregulation of as many as a thousand genes. This remarkable transition prepares cells and organisms for resistance to infection, and many IFN-regulated gene products are players in well-understood resistance programs. Oddly, however, many of the most abundantly induced proteins are GTPases whose functions are not well understood. Here we review the progress that has been made toward understanding the roles of individual GTPase families in disease resistance and the hints of common mechanisms that are now available.
Glucose-dependent expansion of pancreatic β-cells by the protein p8 in vitro and in vivo
Authors: Päth Günter , Opel Anne , Gehlen Martin , Rothhammer Veit , Niu Xinjie , Limbert Catarina , Romfeld Lars , Hügl Sigrun , Knoll Anita , Brendel Mathias D. , Bretzel Reinhard G. , Seufert Jochen
Published: July 2006

p8 protein expression is known to be upregulated in the exocrine pancreas during acute pancreatitis. Own previous work revealed glucose-dependent p8 expression also in endocrine pancreatic β-cells. Here we demonstrate that glucose-induced INS-1 β-cell expansion is preceded by p8 protein expression. Moreover, isopropylthiogalactoside (IPTG)-induced p8 overexpression in INS-1 β-cells (p8-INS-1) enhances cell proliferation and expansion in the presence of glucose only. Although β-cell-related gene expression (PDX-1, proinsulin I, GLUT2, glucokinase, amylin) and function (insulin content and secretion) are slightly reduced during p8 overexpression, removal of IPTG reverses β-cell function within 24 h to normal levels. In addition, insulin secretion of p8-INS-1 β-cells in response to 0–25 mM glucose is not altered by preceding p8-induced β-cell expansion. Adenovirally transduced p8 overexpression in primary human pancreatic islets increases proliferation, expansion, and cumulative insulin secretion in vitro. Transplantation of mock-transduced control islets under the kidney capsule of immunosuppressed streptozotocin-diabetic mice reduces blood glucose and increases human C-peptide serum concentrations to stable levels after 3 days. In contrast, transplantation of equal numbers of p8-transduced islets results in a continuous decrease of blood glucose and increase of human C-peptide beyond 3 days, indicating p8-induced expansion of transplanted human β-cells in vivo. This is underlined by a doubling of insulin content in kidneys containing p8-transduced islet grafts explanted on day 9. These results establish p8 as a novel molecular mediator of glucose-induced pancreatic β-cell expansion in vitro and in vivo and support the notion of existing β-cell replication in the adult organism.
Long-term hypoxia increases leptin receptors and plasma leptin concentrations in the late-gestation ovine fetus
Authors: Ducsay Charles A. , Hyatt Kim , Mlynarczyk Malgorzata , Kaushal Kanchan M. , Myers Dean A.
Published: July 2006

This study was designed to test the hypothesis that long-term hypoxia (LTH) increases fetal plasma leptin and fetal adipose or placental leptin expression and alters hypothalamic and adrenocortical leptin receptor (OB-R) expression. Pregnant ewes were maintained at high altitude (3,820 m) from day 30 to ∼130 days of gestation. Reduced Po2 was maintained in the laboratory by nitrogen infusion through a maternal tracheal catheter. On day 132, normoxic control and LTH fetuses underwent surgical implantation of vascular catheters ( n = 6 for each group). Five days after surgery, maternal and fetal arterial blood samples were collected for leptin, insulin, and glucose analysis. Placental tissue, periadrenal fat, and fetal hypothalami and adrenal glands were collected from additional control ( n = 7) and LTH ( n = 8) fetuses for analysis of leptin mRNA by quantitative, real-time, RT-PCR (qRT-PCR). There was a significant ( P < 0.03) elevation in fetal plasma leptin in the LTH fetuses (3.5 ± 0.7 ng/ml) vs. control (1.1 ± 0.1 ng/ml). There were no differences in either glucose or insulin concentrations between the two groups. Periadrenal adipose leptin mRNA was significantly higher in the LTH group compared with control, as was placental leptin expression. The levels of leptin mRNA in adipose were ∼70 times higher vs. placenta. LTH significantly reduced expression of OB-Ra (short-isoform) in the hypothalamus ( P = 0.0156), while resulting in a significant increase in adrenal OB-Rb (long-form) expression ( P < 0.03). Our data suggest that leptin is a hypoxia-inducible gene in the ovine fetus and OB-R expression is altered by LTH. These changes may be responsible in part, for our previously observed alterations in fetal hypothalamic-pituitary-adrenal function following LTH.
Role of the p38 Mitogen-Activated Protein Kinase Pathway in the Generation of Arsenic Trioxide–Dependent Cellular Responses
Authors: Giafis Nick , Katsoulidis Efstratios , Sassano Antonella , Tallman Martin S. , Higgins Linda S. , Nebreda Angel R. , Davis Roger J. , Platanias Leonidas C.
Published: July 2006

Arsenic trioxide (As2O3) induces differentiation and apoptosis of leukemic cells in vitro and in vivo, but the precise mechanisms that mediate such effects are not known. In the present study, we provide evidence that the kinases MAPK kinase 3 (Mkk3) and Mkk6 are activated during treatment of leukemic cell lines with As2O3 to regulate downstream engagement of the p38 mitogen-activated protein kinase. Using cells with targeted disruption of both the Mkk3 and Mkk6 genes, we show that As2O3-dependent activation of p38 is defective in the absence of Mkk3 and Mkk6, establishing that these kinases are essential for As2O3-dependent engagement of the p38 pathway. Pharmacologic inhibition of p38 enhances As2O3-dependent activation of the c-jun NH2-terminal kinase (JNK) and subsequent induction of apoptosis of chronic myelogenous leukemia (CML)– or acute promyelocytic leukemia (APL)–derived cell lines. In addition, in APL blasts, inhibition of p38 enhances myeloid cell differentiation in response to As2O3, as well as suppression of Bcl-2 expression and loss of mitochondrial membrane potential. Similarly, induction of As2O3-dependent apoptosis is enhanced in mouse embryonic fibroblasts (MEF) with targeted disruption of both the Mkk3 and Mkk6 genes, establishing a key role for this pathway in the regulation of As2O3-induced apoptosis. In other studies, we show that the small-molecule p38 inhibitors SD-282 and SCIO-469 potentiate As2O3-mediated suppression of myeloid leukemic progenitor growth from CML patients, indicating a critical regulatory role for p38 in the induction of antileukemic responses. Altogether, our data indicate that the Mkk3/6-p38 signaling cascade is activated in a negative regulatory feedback manner to control induction of As2O3-mediated antileukemic effects. (Cancer Res 2006; 66(13): 6763-71)
Low Multiplicity of Infection ofHelicobacter pyloriSuppresses Apoptosis of B Lymphocytes
Authors: Bussiere Francoise I. , Chaturvedi Rupesh , Asim Mohammad , Hoek Kristen L. , Cheng Yulan , Gainor Justin , Scholz Adina , Khan Wasif N. , Wilson Keith T.
Published: July 2006

Helicobacter pylori infection of the human stomach causes chronic gastritis that can lead to gastric cancer. Because activated lymphocytes persist in the gastric mucosa, and because a high multiplicity of infection (MOI) of H. pylori is needed to induce apoptosis in vitro, we speculated that resistance of lymphocytes to apoptosis is an important feature of the immune response to H. pylori. Freshly isolated mouse splenocytes underwent substantial spontaneous apoptosis and displayed a biphasic response to H. pylori, in which low MOI (1-10) markedly inhibited apoptosis, whereas high MOI (≥75) potentiated apoptosis. Low MOI reduced mitochondrial membrane depolarization, caspase-3 and caspase-9 activation, and cytochrome c release and increased Bcl-2 levels. Low MOI also induced cellular proliferation. When cells were subjected to fluorescence-activated cell sorting after coculture with H. pylori, CD19+ B cells were found to be protected from apoptosis and undergoing proliferation at low MOI, whereas CD3+ T cells did not exhibit this pattern. The protective effect of low MOI on apoptosis persisted even when B cells were isolated before activation. Immunophenotyping showed that all B-cell subsets examined were protected from apoptosis at low MOI. Additionally, gastric infection with H. pylori resulted in protection of splenic B cells from spontaneous apoptosis. Our results suggest that the low levels of H. pylori infection that occur in vivo are associated with B-cell survival and proliferation, consistent with their potential to evolve into mucosa-associated lymphoid tissue lymphoma. (Cancer Res 2006; 66(13): 6834-42)
Gene Expression Differences in Normal Esophageal Mucosa Associated with Regression and Progression of Mild and Moderate Squamous Dysplasia in a High-Risk Chinese Population
Authors: Joshi Nina , Johnson Laura Lee , Wei Wen-Qiang , Abnet Christian C. , Dong Zhi-Wei , Taylor Philip R. , Limburg Paul J. , Dawsey Sanford M. , Hawk Ernest T. , Qiao You-Lin , Kirsch Ilan R.
Published: July 2006

A randomized, double-blinded, placebo-controlled 2 × 2 factorial chemoprevention trial was conducted in Linxian, China to assess the effects of selenomethionine and celecoxib on the natural history of esophageal squamous dysplasia. Results from this study indicated that asymptomatic adults with mild dysplasia were more likely to show an improvement when treated with selenomethionine compared with placebo (P = 0.02). Prompted by this finding, we examined the molecular profiles associated with regression and progression of dysplastic lesions in normal mucosa from 29 individuals, a subset of the Linxian cohort, using the Affymetrix U133A chip. Twenty differentially expressed genes were associated with regression and 129 were associated with progression when we compared the change in gene expression over time. Genes associated with immune response (n = 15), cell cycle (n = 15), metabolism (n = 15), calcium transport or calcium ion activity (n = 10), regulation of transcription (n = 9), signal transduction (n = 7), cytoskeleton and microtubules (n = 5), nucleotide processing and biosynthesis (n = 4), G-coupled signaling (n = 4), and apoptosis (n = 3) were present in the list of 149 genes. Using the Expression Analysis Systematic Explorer pathway analysis program, only the immune response pathway was significantly overrepresented among these 149 genes. Individuals whose lesions regressed seemed to have higher expression of genes associated with immune stimulation, such as antigen presentation, survival of T cells, and T-cell activation (HLA-DRA, HLA-DPA1, HLA-DBQ1, CD58, and FCER1A). In contrast, individuals whose lesions progressed had higher expression of genes involved in immune suppression and inflammation (CNR2, NFATC4, NFRKB, MBP, INHBB, CMKLR1, CRP, ORMS, SERPINA7, and SERPINA1). These data suggest that local and systemic immune responses may influence the natural history of esophageal squamous dysplasia. (Cancer Res 2006; 66(13): 6851-60)
Repression of Prostaglandin Dehydrogenase by Epidermal Growth Factor and Snail Increases Prostaglandin E2 and Promotes Cancer Progression
Authors: Mann Jason R. , Backlund Michael G. , Buchanan F. Gregory , Daikoku Taki , Holla Vijaykumar R. , Rosenberg Daniel W. , Dey Sudhansu K. , DuBois Raymond N.
Published: July 2006

Prostaglandin E2 (PGE2), a proinflammatory bioactive lipid, promotes cancer progression by modulating proliferation, apoptosis, and angiogenesis. PGE2 is a downstream product of cyclooxygenase (COX) and is biochemically inactivated by prostaglandin dehydrogenase (PGDH). In the present study, we investigated the mechanisms by which PGDH is down-regulated in cancer. We show that epidermal growth factor (EGF) represses PGDH expression in colorectal cancer cells. EGF receptor (EGFR) signaling induces Snail, which binds conserved E-box elements in the PGDH promoter to repress transcription. Induction of PGE2 catabolism through inhibition of EGFR signaling blocks cancer growth in vivo. In human colon cancers, elevated Snail expression correlates well with down-regulation of PGDH. These data indicate that PGDH may serve a tumor suppressor function in colorectal cancer and provide a possible COX-2–independent way to target PGE2 to inhibit cancer progression. (Cancer Res 2006; 66(13): 6649-56)
The Fantasy of Genesis 1-3
Authors: Boer Roland
Published: July 2006

In beginning the search for an adequate theory of literary production in biblical studies, this article seeks to bring together the theoretical sophistication of psychoanalytic studies of Genesis 1-3 and the historical concerns of other studies. The argument is that Genesis 1-3 may be understood in terms of fantasy, particularly in its five modes of narrative occlusion, the paradox of emergence and loss, intersubjective desire, the inherent transgression and the empty gesture. The schema of fantasy also offers the groundwork for a theory of literary production: it takes as its starting point the idea that the reality that lies 'behind' the text, that seems to inform it, is in fact highly unstable, subject to the unsettling presence of a much deeper, unknown fantasmatic kernel.
The Legacy of Bishop Frank Weston of Zanzibar 1871-1924 in the Global South Anglicanism
Authors: Byaruhanga Christopher
Published: July 2006

The idea of comprehensiveness, which I call 'facing-both-ways' in matters of faith, is unknown, at least for now, in the Global South Anglicanism where the Anglican Church is used to preaching the Gospel plainly and unmistakably. The story of homosexuality in the Anglican Communion came to the spotlight at the 1998 Lambeth Conference, at which the Anglican bishops of the Global South of the Anglican Communion emerged as the most prominent opponents of any form of approval of homosexual practice by the Anglican Church. By asking the hard question as Bishop Frank Weston of Zanzibar did in 1913: Anglican Communion: For What Should She Stand? Anglican bishops of the Global South of the Anglican Communion drew the Communion's attention to the place and role of Global South Anglicanism in the Communion and World Christianity.
The Impact of Spectral Nudging on Cloud Simulation with a Regional Atmospheric Model
Authors: Meinke Insa , Geyer Beate , Feser Frauke , von Storch Hans
Published: July 2006

The impact of spectral nudging on cloud simulation with a regional atmospheric model was examined. Simulated cloudiness of the Regional Model (REMO) and the Spectrally Nudged REMO (SN-REMO) were intercompared and evaluated with satellite-derived cloudiness from the International Satellite Cloud Climatology Project (ISCCP). In general, the additional spectral nudging does not affect the mean cloud simulation. However, for particular weather regimes the introduction of spectral nudging causes notable differences in cloud simulation. Two weather conditions for these large differences in cloud simulation were derived: 1) change of the general circulation patterns, or 2) strong anticyclonic circulation within the model domain. Case studies of these weather situations indicated a better agreement of simulated and satellite-derived cloudiness when spectral nudging has been applied to the regional model.
Accuracy of Measurements of Turbulent Phenomena in the Surface Layer with an Ultrasonic Anemometer
Authors: Contini D. , Donateo A. , Belosi F.
Published: July 2006

Ultrasonic anemometers are widely used to investigate turbulence in the surface layer. Some of their advantages are high-frequency sampling, the ability to work for long periods without a resident operator (even in adverse meteorological conditions), and their calibration related only to design parameters. In this paper an analysis of the random uncertainty associated with ultrasonic anemometer measurements is reported. The analysis is based on a statistical procedure that compares the simultaneous data taken with two identical anemometers operating in nominally identical conditions. Postprocessing of data has been carried out in different reference systems in order to evaluate how the random uncertainties change according to the postprocessing procedure used. Results show that uncertainty on wind velocity decreases with averaging time, and it can be as low as 1 cm s−1 for a typical averaging time of 30 min. The random uncertainty on average vertical wind velocity 〈w〉 could also be as low as 1 cm s−1, and it is very sensitive to the effects of vertical misalignment. The analysis is based on six different measurement sets in which the anemometers have been deployed on a single mast or in two separate masts with and without additional detectors placed near the anemometers themselves. Results indicate that the uncertainty of all the measured parameters increases when the anemometer is used in configurations in which they are placed on separate masts. Several parameters also show an additional increase of uncertainty if other detectors are placed nearby. The relative random uncertainty on momentum and sensible heat fluxes, for typical averaging time, can be as low as 6%–7% and it could increase to a factor of 2–3 when they are placed on separate masts. Only small effects due to the influence of flow distortions caused by the presence of additional sensors have been found on fluxes and are mainly related to sensible heat flux.
Effect of bladder volume on measured intravesical pressure: a prospective cohort study
Authors: Malbrain Manu LNG , Deeren Dries H
Published: July 2006

Introduction

Correct bedside measurement of intra-abdominal pressure (IAP) is important. The bladder method is considered as the gold standard for indirect IAP measurement, but the instillation volumes reported in the literature vary substantially. The aim of this study was to evaluate the effect of instillation volume on intra-bladder pressure (IBP) as an estimation for IAP in critically ill patients.

Methods

In this prospective cohort study in 13 sedated and mechanically ventilated patients, we used a revised closed system repeated measurement technique for measurement of IBP. After the system was flushed, IBP was measured with 25 ml increments up to 300 ml. The absolute bias for each volume was calculated as IBP at a given volume minus IBP at zero volume.

Results

In total, 30 measurement sets were performed (mean 2.3 per patient). The median IBP at 25 ml was already significantly higher than IBP at zero volume (7.5 versus 6 mmHg). There was no correlation between IBP at zero volume and absolute IBP bias at any bladder volume. Median absolute IBP bias was 1.5 mmHg at 50 ml; 2.5 mmHg at 100 ml; 5.5 mmHg at 150 ml; and up to 11 mmHg at 300 ml.

Conclusion

Larger instillation volumes than the usually recommended 50 ml to estimate IAP by bladder pressure may cause clinically relevant overestimation of IAP. Small volumes to a maximum of 25 ml, enough to create a fluid column and to remove air, may be sufficient.
Influence of Surgical Manipulation on Prostate Gene Expression: Implications for Molecular Correlates of Treatment Effects and Disease Prognosis
Authors: Lin Daniel W. , Coleman Ilsa M. , Hawley Sarah , Huang Chung Y. , Dumpit Ruth , Gifford David , Kezele Philip , Hung Hau , Knudsen Beatrice S. , Kristal Alan R. , Nelson Peter S.
Published: July 2006

Purpose

Measurements of tissue gene expression are increasingly used for disease stratification, clinical trial eligibility, and assessment of neoadjuvant therapy response. However, the method of tissue acquisition alone could significantly influence the expression of specific transcripts or proteins. This study examines whether there are transcript alterations associated with surgical resection of the prostate gland by radical retropubic prostatectomy.

Materials and Methods

Twelve patients with clinically localized prostate cancer underwent immediate in situ prostate biopsy after induction of anesthesia for radical prostatectomy. Ex vivo prostate biopsies were performed immediately after surgical removal. Prostate epithelium was acquired by laser-capture microdissection, and transcript abundance levels were quantitated by cDNA microarray hybridization and confirmed by quantitative polymerase chain reaction. Data were analyzed by paired, two-sample t test using Statistical Analysis of Microarray algorithms, and linear models were fit as a function of clinical characteristics.

Results

Of 5,753 cDNAs with measurable expression in prostate epithelium, 88 (1.5%) were altered as a result of surgery (false-discovery rate ≤ 10%), representing 62 unique genes. These included transcripts encoding acute phase response proteins, IER2 and JUNB, and regulators of cell proliferation, p21Cip1 and KLF6. Of the clinical characteristics examined, including patient age, prostate volume, serum prostate-specific antigen, blood loss, and operative time, only gland volume was significantly and negatively associated with the magnitude of gene expression difference between pre- and postsurgical specimens.

Conclusion

Surgical manipulation results in significant gene expression changes. Molecular analyses of surgical samples should recognize that transcript alterations occur rapidly, and these results are important when designing and analyzing molecular correlates of clinical studies.