bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thrombocytopenia alters early but not late repair in a mouse model of Achilles tendon injury
Authors: Godbout Charles , Bilodeau Rosalie , Bouchard Patrice , Frenette Jérôme 
Published: March 2009

ABSTRACTBesides their hemostatic function, platelets can express key factors involved in tissue healing. However, the role of platelets in tendon healing following acute injury is poorly understood. We investigated this role by injecting male C57BL/6 mice with an antiplatelet antibody to induce thrombocytopenia. Placebo animals received serum only. The right Achilles tendon was sectioned and sutured using the 8‐strand technique that allows immediate weight bearing. Platelet depletion did not alter the accumulation of neutrophils and macrophages or cell proliferation. A slight increase in vascularization was observed 7 days postinjury in tendons from thrombocytopenic mice relative to placebo animals, but the effect had disappeared by day 14. Furthermore, collagen content had a tendency to decrease in Achilles tendons under thrombocytopenia when compared with placebo treatment at 7 days posttrauma. This was correlated with a decline in maximal stress sustained by tendons at day 14 but not after 28 days. The impact of thrombocytopenia was otherwise negligible, as force relaxation and stiffness were similar in the two groups. Our findings demonstrate that platelets modulate early tendon repair following rupture, although the effect is limited over time. Nevertheless, platelets are not essential for the recruitment of inflammatory cells, proliferation, angiogenesis, and tendon maturation.
Ethanol‐Sensitive Brain Regions in Rat and Mouse: A Cartographic Review, Using Immediate Early Gene Expression
Authors: Vilpoux Catherine , Warnault Vincent , Pierrefiche Olivier , Daoust Martine , Naassila Mickael 
Published: March 2009

Background: Ethanol addiction has been conceptualized as a progression from occasional, impulsive use to compulsive behavior. Ethanol‐dependence is a chronic pathology with repeated cycles of withdrawal, craving, and relapse. Specific molecular and cellular mechanisms underlie these transition stages.Methods: This review aimed at elucidating whether there are also adaptations in the pattern of brain regions responding to ethanol. This paper reviews the evidence in rodents for activation of specific brain regions, assessed by induction of IEG expression, following acute and chronic ethanol exposure.Results: The review sheds light on the specific patterns of response in regions of the brain to different types of ethanol exposure and shows that activation of specific brain regions may occur in particular phases of the development of ethanol addiction. Some brain regions respond consistently following acute or chronic treatments or withdrawal: the prefrontal cortex; nucleus accumbens; lateral septum; hippocampus; perioculomotor urocortin‐containing cells population (pIIIu), also known as Edinger‐Westphal nucleus; central nucleus of the amygdale; and the paraventricular nucleus of hypothalamus. The two last brain areas are particularly activated by relapse‐inducing stressors. It is of interest that the amygdala, hippocampus, and prefrontal cortex, which belong to the reward system, are activated by cue‐induced relapse to ethanol self‐administration in rodents and humans, while activation of these regions is reversed with anticraving compounds. Following chronic exposure, IEG induction desensitizes while withdrawal reactivates these regions.Discussion: Some responding regions are implicated in reward related processes (VTA, extended amygdala, hypothalamus, hippocampus, prelimbic cortex, ventral part of lateral septum) and some others in aversive‐related processes (area postrema, nucleus of solitary tract).Conclusion: A better understanding of the neural circuits affected by ethanol and their adaptations during the development of ethanol addiction will provide new opportunities for developing appropriate therapies.
Ethanol‐Induced Social Facilitation in Adolescent Rats: Role of Endogenous Activity at Mu Opioid Receptors
Authors: Varlinskaya Elena I. , Spear Linda P. 
Published: March 2009

Background: Ethanol consumption is considerably elevated during adolescence. Attractiveness of alcohol for humans during the adolescent developmental period is based, in part, on its ability to induce social facilitation—a facilitation of social interactions not only evident in human adolescents but also in adolescent rats. Endogenous opioid systems are among the multiple neural systems implicated in the behavioral and reinforcing effects of ethanol and may play a substantial role in modulating stimulatory effects of low doses of ethanol on social behavior during adolescence. This possibility was explored in the present study through the use of an animal model of peer‐directed social behavior.Methods: Sprague–Dawley rats were challenged early in adolescence with saline or ethanol intraperitoneally (i.p.), placed into an individual holding cage for 30 minutes, and then tested in a familiar situation with a nonmanipulated partner of the same age and sex. InExperiment 1, each test subject was injected subcutaneously with one of the three doses of a nonselective opioid antagonist naloxone (0, 0.05, and 0.1 mg/kg), 5 minutes prior to the social interaction test and 25 minutes following challenge with saline or ethanol (0.5 g/kg), whereas inExperiment 2animals were challenged with one of the six doses of ethanol (0, 0.25, 0.5, 0.75, 1.0, and 1.25 g/kg) prior to injection of either saline or naloxone (0.05 mg/kg). InExperiment 3, animals were pretreated i.p. with the selective μ‐opioid antagonist CTOP (0, 0.01, 0.025, 0.05, and 0.1 mg/kg) 30 minutes prior to challenge with saline or ethanol (0.5 g/kg).Results: Low doses of ethanol (0.5 and 0.75 g/kg) produced social facilitation, as indexed by significant increases in play fighting and social investigation. Both doses of naloxone and the three highest doses of CTOP blocked the stimulatory effects of ethanol on play fighting but not on social investigation. These effects were not associated with alterations in ethanol pharmacokinetic properties or with shifts in the biphasic ethanol dose–response curve.Conclusions: Ethanol‐induced facilitation of social play behavior seen in adolescent animals is mediated in part through ethanol‐induced release of endogenous ligands for the μ‐opioid receptor or an ethanol‐associated enhancement of sensitivity of these receptors for their endogenous ligands.
GDNF is an Endogenous Negative Regulator of Ethanol‐Mediated Reward and of Ethanol Consumption After a Period of Abstinence
Authors: Carnicella Sebastien , Ahmadiantehrani Somayeh , Janak Patricia H. , Ron Dorit 
Published: March 2009

Background: We previously found that activation of the glial cell line‐derived neurotrophic factor (GDNF) pathway in the ventral tegmental area (VTA) reduces ethanol‐drinking behaviors. In this study, we set out to assess the contribution of endogenous GDNF or its receptor GFRα1 to the regulation of ethanol‐related behaviors.Methods: GDNF and GFRα1 heterozygote mice (HET) and their wild‐type littermate controls (WT) were used for the studies. Ethanol‐induced hyperlocomotion, sensitization, and conditioned place preference (CPP), as well as ethanol consumption before and after a period of abstinence were evaluated. Blood ethanol concentration (BEC) was also measured.Results: We observed no differences between the GDNF HET and WT mice in the level of locomotor activity or in sensitization to ethanol‐induced hyperlocomotion after systemic injection of a nonhypnotic dose of ethanol and in BEC. However, GDNF and GFRα1 mice exhibited increased place preference to ethanol as compared with their WT littermates. The levels of voluntary ethanol or quinine consumption were similar in the GDNF HET and WT mice, however, a small but significant increase in saccharin intake was observed in the GDNF HET mice. No changes were detected in voluntary ethanol, saccharin or quinine consumption of GFRα1 HET mice as compared with their WT littermates. Interestingly, however, both the GDNF and GFRα1 HET mice consumed much larger quantities of ethanol after a period of abstinence from ethanol as compared with their WT littermates. Furthermore, the increase in ethanol consumption after abstinence was found to be specific for ethanol as similar levels of saccharin intake were measured in the GDNF and GFRα1 HET and WT mice after abstinence.Conclusions: Our results suggest that endogenous GDNF negatively regulates the rewarding effect of ethanol and ethanol‐drinking behaviors after a period of abstinence.
Investor Inattention and Friday Earnings Announcements
Authors: DELLAVIGNA STEFANO , POLLET JOSHUA M. 
Published: March 2009

ABSTRACTDoes limited attention among investors affect stock returns? We compare the response to earnings announcements on Friday, when investor inattention is more likely, to the response on other weekdays. If inattention influences stock prices, we should observe less immediate response and more drift for Friday announcements. Indeed, Friday announcements have a 15% lower immediate response and a 70% higher delayed response. A portfolio investing in differential Friday drift earns substantial abnormal returns. In addition, trading volume is 8% lower around Friday announcements. These findings support explanations of post‐earnings announcement drift based on underreaction to information caused by limited attention.
Securitization and the Declining Impact of Bank Finance on Loan Supply: Evidence from Mortgage Originations
Authors: LOUTSKINA ELENA , STRAHAN PHILIP E. 
Published: March 2009

ABSTRACTLow‐cost deposits and increased balance sheet liquidity raise banks' supply of illiquid loans more than loans easily sold or securitized. We exploit the inability of Fannie Mae and Freddie Mac to purchase jumbo mortgages to identify an exogenous change in liquidity. The volume of jumbo mortgage originations relative to nonjumbo originations increases with bank holdings of liquid assets and decreases with bank deposit costs. This result suggests that the increasing depth of the mortgage secondary market fostered by securitization has reduced the effect of lender's financial condition on credit supply.
Cash Flow, Consumption Risk, and the Cross‐section of Stock Returns
Authors: DA ZHI 
Published: March 2009

ABSTRACTI link an asset's risk premium to two characteristics of its underlying cash flow: covariance and duration. Using empirically novel estimates of both cash flow characteristics based exclusively on accounting earnings and aggregate consumption data, I examine their dynamic interaction in a two‐factor cash flow model and find that they are able to explain up to 82% of the cross‐sectional variation in the average returns on size, book‐to‐market, and long‐term reversal‐sorted portfolios for the period 1964 to 2002. This finding highlights the importance of fundamental cash flow characteristics in determining the risk exposure of an asset.
Hedge Fund Risk Dynamics: Implications for Performance Appraisal
Authors: BOLLEN NICOLAS P.B. , WHALEY ROBERT E. 
Published: March 2009

ABSTRACTAccurate appraisal of hedge fund performance must recognize the freedom with which managers shift asset classes, strategies, and leverage in response to changing market conditions and arbitrage opportunities. The standard measure of performance is the abnormal return defined by a hedge fund's exposure to risk factors. If exposures are assumed constant when, in fact, they vary through time, estimated abnormal returns may be incorrect. We employ an optimal changepoint regression that allows risk exposures to shift, and illustrate the impact on performance appraisal using a sample of live and dead funds during the period January 1994 through December 2005.
Endothelialization of Nonapposed Stent Struts Located over the Origin of a Side Branch: Results with Different Carbofilm‐Coated Stents
Authors: DE PRADO ARMANDO PEREZ , MARTINEZ CLAUDIA PEREZ , RAMON CARLOS CUELLAS , ORDEN J. MANUEL GONZALO , ALTONAGA JOSE R. , IGLESIAS MARIA J. GARCIA , PURRIÑOS MARTA REGUEIRO , ORDEN M. ASUNCION , MARIN JUAN F. GARCIA , FERNANDEZ‐VAZQUEZ FELIPE 
Published: March 2009

Objective: To evaluate the degree of endothelialization of the nonapposed struts located at the ostia of side branches.
Background: Endothelialization of coronary stents has got considerable relevance because of the phenomenon of late thrombosis. Bifurcation location and incomplete stent apposition have been linked to this complication.
Methods: Domestic pigs (n = 11; weight: 25 ± 3 kg) were anesthetized and had one stent per coronary artery implanted: one stainless steel (Tecnic®), one cobalt‐chromium (Chrono®), and one tacrolimus‐eluting stent (Janus®), all of them being Carbofilm®‐coated (Sorin). One, three, or seven days postprocedure, the pigs were sacrificed, the hearts explanted, and longitudinal sections examined by surface electron microscopy to quantify the percentage of the strut endothelialized over the branches and in the total surface.
Results: Forty‐four side branches (25 stents) that had stent struts over their origin were evaluated. Different patterns of endothelialization were observed, from the total absence to the complete endothelialization. There were no significant differences in relation to type of stent or to the artery treated. The predictors of higher percentage of endothelialization were the ratio of metal to branch diameter (P = 0.04) and better endothelialization in the rest of the stent (P = 0.0002), only this parameter maintaining significant correlation (P = 0.03) in multivariate analysis.
Conclusions: Carbofilm®‐coated stent struts located over the origin of side branches follow the pattern of endothelialization for the rest of the stent, even in the case of tacrolimus‐eluting stent.
FOAM‐IN‐SAL VAGE
Authors: WINER ALLEN , MUNGER MILTON 
Published: March 2009

ABSTRACTAside from economics, quality and efficiency of foam formation, the feasibility of generating urethane foam underwater to a simulated depth of 375 feet (165 psig) in 30°F water (without exploding the foam upon decompression) has been demonstrated with a carbon dioxide blown foam in the Laboratory. Large scale feasibility of a methane froth system to foam underwater to 200 feet in the ocean in 50°F water was demonstrated in the San Francisco Bay and again at SEALAB II. To date, service applications for the Foam‐In‐Salvage system have been limited to two stranding type salvage operations involving a destroyer and an LST. Two near surface recovery operations involved a sunken barge and a dredge.Toxicity effects can be minimized in connection with Foam‐In‐Salvage operations by following established precautionary procedures.Studies are continuing to complete the adaptation of the urethane froth system to 200 feet and to extend its capability to 450 feet, if possible. A Foam‐In‐Salvage system procurement specification and operating manual for a 100‐foot operational depth is currently being prepared.Buoyancy systems other than expanded “in‐situ'' systems are also under investigation but for deeper depths to 600 feet.
THE DEVELOPMENT OF MANNED, DEEP‐DIVING SUBMERSIBLES
Authors: RAMSAY RAYMOND 
Published: March 2009

ABSTRACTThe need for maintaining technological leadership in the deep submergence field is given recognition, with particular reference to manned submersibles.A design sequence is outlined to illustrate how operating crew requirements must be satisfied very early in the design process to insure maximum overallmission effectiveness.The necessity for more technologists and “totally immersed” projects to manage future vehicle technology efforts is also addressed.
PLASTIC FOAMS FOR MARINE SALVAGE
Authors: WINER ALLEN , SEARLE W. F. 
Published: March 2009

ABSTRACTTwo quite different plastic foam systems are described for raising large sunken objects; Urethane Foam‐In‐Salvage (FIS) and Expanded Polystyrene Bead (EPS) systems. This paper will first review the major salvage operations in which the FIS and EPS internal buoyancy systems have been employed and second, address the technology involved.An FIS system operational to an ocean depth of 200 feet is presented and a possible technique for extending FIS depth capability to 450 feet is described. FIS is considered to be a breakthrough in technology in the ship salvage field.Successful salvage recoveries of sunken vessels involving the use of plastic foam systems are also described. There are specific advantages and disadvantages associated with each of the two systems.
A DIFFERENT APPROACH TO SOME PROBLEMS OF RELIABILITY WITHIN THE NAVY COMPLEX
Authors: LA ROUCHE ARDIAN J. 
Published: March 2009

ABSTRACTIt has become obvious that the problems of reliability of intermittently used shipboard equipment are both urgent and acute. While the results of leaving these problems entirely with designers have been disappointing they should not be surprising. The problem is not simply a technical one and it can not be solved through design improvements alone.This paper presents a detailed discussion of the problems and how these relate to areas beyond the engineer's control. It also reviews the engineer's responsibility in analyzing the operational and organizational influence on the system. In addition, it supports the proposition that the engineering community must take the lead in recommending to management appropriate action to solve the problems. Potential approaches to the overall problem are presented for consideration by both the engineering community and management.
Atmospheric Control in the Hyperbaric Environment
Authors: REIMERS LIEUTENANT (JG) S. D. 
Published: March 2009

ABSTRACTCareful control of the atmosphere in a hyperbaric facility is necessary to protect the health and well‐being of the occupants. In this paper total environmental control in the hyperbaric chamber is broken down into eight subareas of control: total pressure, oxygen partial pressure, CO2 partial pressure, fire prevention, temperature, humidity, trace contaminants, bacteria, and noise. For each subarea an assessment is given of the difficulty and degree of control required and its importance to the divers' well‐being. Also discussed for each subarea are the state of the art, and the areas of greatest technological need.Control of oxygen and CO2 partial pressure in breathing circuits of diving equipment is described. Methods of heating the diver and his inspired gas are also briefly discussed.
Control of Shipboard Wastes
Authors: KINNEY EDWARD T. , CONSTANT ALEXANDER 
Published: March 2009

ABSTRACTThe Navy, as well as other Federal Agencies and the private sector, has a clear mandate to stop polluting the environment, Various sources of environmental pollution caused by the operation of naval ships are discussed and characterized by the following general categories: Sewage; Oil; Industrial; Combustion Products; and Other Mission Related Wastes. Existing procedures for controlling these pollutants and advanced concepts for more complete control are discussed.Currently a very small percentage of ships are equipped to control environmental pollution. Complete control of ship wastes will be very costly and technically challenging. The first steps to effect control have been taken but greater strides are required.
Comparative Heave Dynamics Of Two Unusual Ship Configurations For Recovery Of Submersibles
Authors: MOTHERWAY D. L. , HELLER S. R. 
Published: March 2009

ABSTRACTThe comparative heaving characteristics of two unusual ship configurations, a spar‐type ship similar to FLIP and a catamaran which employs a submerged cradle suspended by sophisticated motion attenuation devices, for recovery of small submersibles are presented. The two ships are described and their heaving characteristics are determined analytically using classical vibration theory.
Salt Water Chlorine Ion Determination By Neutron‐Capture Gamma Rays
Authors: WIGGINS PETER F. , ATHOW MIDSHIPMAN KARL J. 
Published: March 2009

ABSTRACTIdentification of ocean flow patterns is of interest to ocean engineers because of their effects on ocean current diffusion. The change in salinity in the ocean near where a fresh water river enters the sea is of particular interest. In addition, a rapid, accurate method of chlorine concentration could be helpful in sonar detection applications i.e. location of inversion layers.This paper will discuss the feasibility of using the neutron‐capture gamma rays produced by chlorine, as an in situ method from which salinity contours could be obtained. The bending of these contours show the current flow.
RISK MANAGEMENT KEEPS AIRCRAFT CARRIER OVERHAUL PLANNING ON SCHEDULE
Authors: JURGES GLEN F. 
Published: March 2009

ABSTRACTThis paper advances a new method for managing the risks involved in planning aircraft carrier overhauls. Risk is the degree of likelihood that a planning project will not be completed as predicted. The paper describes the techniques for identifying major planning risks and reducing them to acceptable levels. Called “Risk Management,” the technique was successfully used for planning the $40‐million overhaul of the aircraft carrier USS JOHN F. KENNEDY. It substantially reduced the planning time and cost.
SMALL PROTOTYPES OF SHIPS—THEORY AND A PRACTICAL EXAMPLE
Authors: MARBURY FENDALL 
Published: March 2009

ABSTRACTTo further the development of an out‐of‐the ordinary type ship, the Small Waterplane Area Twin Hull Ship (SWATHS), a small‐scale prototype, was built and tested. The purpose of this paper is to explain what has been accomplished by the construction and operation of this particular prototype, and, more generally, the purpose to be served by such prototypes.The question arises: Why is the conventional displacement ship so resistant to fundamental change? The hypothesis is advanced and supported that ship design relies heavily on experience, despite scientific advances which tend to give the opposite impression. When a ship is built that goes far beyond the existing experience base, something unexpected ordinarily happens, and ordinarily IT IS BAD. The small prototype provides the first direct experience with the new type of ship. This experience guides subsequent engineering development and the design of the first full‐scale ship. The prototype also can be used to acquaint the first ship's prospective crew with the unfamiliar handling qualities of the new type.Such a prototype of the Small Waterplane Area Twin Hull Ship is described and discussed. Described is the behavior of this craft together with the lessons drawn from it and the modification that had to be made. The relations between small‐scale and full‐scale behavior also are discussed.
GENERAL CONCEPTS FOR A COMBINED HALON‐HIGH EXPANSION FOAM FIRE PROTECTION SYSTEM FOR SHIPBOARD APPLICATION
Authors: GUSTAFSON R. E. , SCHAB H. W. 
Published: March 2009

AbstractExamination of the special requirements for fire protection systems and procedures in high‐performance ships constructed of light weight aluminum, such as hydrofoils, emphasizes the necessity for extremely rapid detection and response coupled with automatic and remotely controlled operations of the firefighting systems. Small crews, difficulty of access, minimum reaction time, and vulnerability of the equipment virtually eliminate dependence on the more conventional firefighting equipments. An installed HALON flooding system, with a back‐up system of installed high expansion foam generators, is recommended for protection of high‐performance craft in excess of 100 tons. A brief series of tests with high expansion foam showed it to be very effective in an oil spray fire. Foam, fortified with a 4% addition of HALON in the air bubbles, proved to be quite superior to unfortified foam.