bluuebunny/crossref_metadata_2025 huggingface dataset:
Injuries associated with fireworks in Victoria: an epidemiological overview: Table 1
Authors: Abdulwadud Omar , Ozanne-Smith Joan
Published: December 2008

Objectives—To determine the epidemiological features of injuries associated with fireworks.

Design—A retrospective study of reported cases.

Subjects—Subjects were those who attended selected Victorian hospital emergency departments (n=17) and those admitted for firework related injuries (n=16).

Results—The mean (SD) age of attenders at emergency department between January 1988 and June 1996, was 8.9 (6.2) years and most (88%) were under 18 years of age. Males accounted for 71% of the cases. The most common anatomical sites and types of injury were head (47%) and burns (88%), respectively. About 53% of the injuries were caused by firecrackers, the remainder by sparklers and penny bangers. Among those admitted to hospital between July 1987 and June 1996, the mean (SD) age was 22.9 (14.8) years and 50% were under 18 years of age. Males accounted for 87% of the cases. There was a significant difference in mean age between those admitted and not admitted to hospital, the former being significantly older.

Conclusions—Although relatively rare, injuries from fireworks still occur in Victoria after legislative restrictions on their sale in 1985. Consequently, there is a potential risk for injuries among children, particularly from firecrackers. More enforcement of the regulations, education, and parental supervision are needed to prevent injuries from fireworks.
Young driver involvement in fatal motor vehicle crashes and trends in risk behaviors, United States, 1988–95
Authors: Phebo Luciana , Dellinger Ann M
Published: December 2008

Objective—To review trends and risk factors in fatal motor vehicle crashes (MVCs) for drivers aged 15–20 years.

Methods—Fatality Analysis Reporting System data from 1988 to 1995 were used. Drivers were divided into three age strata: 15–17 years, 18–20 years, and ≥21 years. Comparisons were made based on rates of driver involvement in fatal MVCs, the percentage of drivers involved in night time fatal MVCs, fatal MVCs without the use of restraints, and fatal MVCs with positive blood alcohol concentration.

Results—Over the eight years, the rate of driver involvement in fatal MVCs for those 15–17 dropped 15.5%; for those 18–20 years it dropped 22.0%, and for those ≥21 years it declined 13.5%. When combining both age groups results were similar. In 1988, 60.4% of young drivers involved in fatal MVCs were not using restraints, but by 1995 the percentage dropped to 46.0%. Night time fatal crashes, the second most frequent risk behavior, declined from 41.7% in 1988 to 35.2% in 1995. Alcohol related traffic fatalities were responsible for 32.1% of fatal MVCs among young drivers in 1988 and for 20.3% in 1995.

Conclusion—To accelerate these trends, implementation and evaluation of complete graduated driver licensing systems (GDLSs) is recommended. Under GDLSs, young drivers are subject to zero alcohol tolerance, curfews, and passenger restraint requirements.
Parental decisions to use infant walkers
Authors: Bar-on Miriam E , Boyle Russell M , Endriss E Kay
Published: December 2008

Objective—To assess parental decision making in the acquisition of an infant walker and the influences surrounding that decision.

Design/methods—Caretakers of children attending a residents' continuity practice during a one month period were invited to participate in a structured interview to assess various aspects of infant safety. Ten questions specifically addressed infant walkers and the decision to acquire one; seven questions collected demographic data.

Results—One hundred and fifty four primary caretakers participated. Of these, 77% (n=119) of caretakers used infant walkers for their child. For children who were not first born, 85% of caretakers had used walkers with their other children. No statistically significant differences were found between walker users and non-users with respect to the sex or birth order of the child, race, education, or (type of) caretaker. Also, no differences were found between these groups with respect to having received safety information from the pediatrician. For users, 97% heard about walkers before their baby's birth, but 65% did not decide to use one until after the birth. In addition, 61% of walker users stated that no one influenced their decision to get a walker and 75% bought their own. These decisions were not affected by caretaker education or birth order of the child. Finally, 78% believed that walkers were beneficial, and 72% believed that walker use accelerated development of independent walking skills.

Conclusions—Mothers purchased walkers because of no uniformed perception of benefit. A period of time, up to several months in length, exists from when the first mother hears about walkers until she decides to purchase one. Until legislation can be passed banning walkers, this period of time may provide a window of opportunity for appropriate anticipatory guidance in the form of intense media assisted, antiwalker campaigns.
One pediatric burn unit's experience with sleepwear related injuries
Authors: McLoughlin Elizabeth , Clarke Nicola , Stahl Kent , Crawford John D
Published: December 2008

Review of the records of 678 children with acute injuries referred during an eight year period to this burn unit indicated that flame burns from a single ignition source (50%) outranked scalds (27%) or house fires (12%) as causes of injury. There was no temporal trend in the rank pattern. The majority of these single-source flame injuries were severe and involved ignition of the child's clothing. From 1969 through 1973, sleepwear was the clothing involved in 32% of the instances. Since that time and coincident with promulgation of strict federal and state standards for flammability of children's night clothing, a dramatic decline in the number of children referred with injuries of this type has taken place. It is probable that the single factor most important to the decline, in our experience with these injuries, is lower fabric flammability but, because our data may not be representative, corroboration is needed before one can exclude factors such as altered garment design, fire safety related practices at home, or changing patterns of hospital referral.
Pediatric practice based evaluation of the Steps to Prevent Firearm Injury program
Authors: Oatis Pamela J , Buderer Nancy M Fenn , Cummings Peter , Fleitz Rosemarie
Published: December 2008

Objective—To estimate the prevalence of gun ownership and methods of gun storage in homes of pediatric patients before and after an educational intervention.

Design—Before and after trial.

Setting—Hospital based, inner city, pediatric primary care practice.

Participants—Consecutive sample of parents of patients with appointments August to November 1994.

Intervention—Before the intervention, participants completed an anonymous questionnaire regarding ownership and storage of guns in their home. The intervention followed the Steps to Prevent Firearm Injury program of the American Academy of Pediatrics. It began after the parent completed the questionnaire and was reinforced at subsequent visits until July 1995. Families completing a baseline questionnaire and returning to the office July to October 1995 were resurveyed.

Main outcome measure—Reported change in gun ownership and methods of storage.

Results—A gun(s) in the home was reported by 8.7% of respondents. Matched baseline and follow up questionnaires were available for 23.6% of families. In these, gun ownership reportedly decreased after intervention from 9.4% to 7.0%, handgun ownership fell from 5.4% to 3.0%, and long gun ownership fell from 6.1% to 5.5%. Storing guns outside of a locked container did not change from the baseline prevalence of 2.7%, but keeping any gun loaded fell from 1.6% to 0.5%. All p values were >0.05.

Conclusion—This study was unable to demonstrate a statistically significant decline in gun ownership or improvement in gun storage after a practice based intervention designed to encourage these behaviors.
Evaluating the impact of a street barrier on urban crime
Authors: Zavoski Robert W , Lapidus Garry D , Lerer Trudy J , Burke Georgine , Banco Leonard I
Published: December 2008

Objectives—Violence is a major urban public health problem in the United States. The impact of a physical barrier placed across a street in a public housing project to prevent street violence and drug activity was evaluated.

Methods—Hartford Police Department data on violent and drug related crime incidence within the housing project containing the barrier were analyzed by use of a computerized geographic information system.

Results—Violent crime decreased 33% on the intervention street during the 15 month period after erection of the barrier, compared with the 15 month period before erection of the barrier, but there was no change in drug related crime. On adjoining streets and surrounding blocks, violent crime decreased 30%–50% but drug related crimes roughly doubled. A non-adjacent area of the housing project and the entire city experienced 26% and 15% decreases in violent crimes, and 414% and 25% increases in drug crimes, respectively.

Conclusions—The barrier decreased violent crime but displaced drug crimes to surrounding areas of the housing project. These results have important implications for other cities that have erected or are considering erecting similar barriers.
Risk of upper limb injury in left handed children: a study in Greece
Authors: Skalkidou Alkistis , Petridou Eleni , Dessypris Nick , Karanikas Elias , Pistevos George , Trichopoulos Dimitrios
Published: December 2008

Objectives—To investigate whether left handed children are at increased risk for injuries, particularly upper limb injuries.

Setting—Athens, Greece, during a six month period in 1995–96.

Methods—Cases were 129 children 4–14 years old with unintentional upper limb injuries from a population based injury database. Two control children matched for gender and age were selected from among those seen at the same medical institution for minor, non-injury ailments. On the basis of information provided by the children and their guardians, sociodemographic variables were recorded, hand preference was assessed, and each child's activity score was calculated through an abbreviated version of Achenbach's scale.

Results—Left handed children have a moderately increased upper limb injury risk with a tendency of recurrence of this injury. The risk of upper limb injury is also raised among children of young fathers, whereas it appears to be inversely related to crowding index and activity score—three variables that were controlled for as potential confounders.

Conclusions—This study provides limited support for the hypothesis that left handed children are at increased risk for injury. The excess risk, if genuine, is likely to be limited to cultural settings in which right handedness is perceived as the norm.
An intervention to reduce playground equipment hazards
Authors: Roseveare Christine A , Brown Judith M , McIntosh Jillian M Barclay , Chalmers David J
Published: December 2008

Objectives—A community intervention trial was carried out to evaluate the relative effectiveness of two methods of reducing playground hazards in schools. The study hypotheses were: (1) a health promotion programme addressing barriers to implementing the New Zealand Playground Safety Standard will reduce playground hazards and (2) the intervention programme will be more successful than providing information alone.

Methods—Twenty four schools in Wellington, New Zealand were randomly allocated into two groups of 12 and their playgrounds audited for hazards. After the audit, the intervention group received a health promotion programme consisting of information about the hazards, an engineer's report, regular contact and encouragement to act on the report, and assistance in obtaining funding. The control group only received information about hazards in their playground.

Results—After 19 months, there was a significant fall in hazards in the intervention schools compared with the control schools (Mann-Whitney U test, p=0.027). No intervention schools had increased hazards and eight out of 12 had reduced them by at least three. In contrast, only two of the control schools had reduced their hazards by this amount, with three others increasing their hazards in that time.

Conclusions—It is concluded that working intensively with schools to overcome barriers to upgrading playground equipment can lead to a reduction in hazards, and that this form of intensive intervention is more effective than providing information alone.
Validity of self reported crashes and injuries in a longitudinal study of young adults
Authors: Begg Dorothy J , Langley John D , Williams Sheila M
Published: December 2008

Objectives—The aim of this study was to determine the validity of self report as a source of information on crashes and injuries.

Setting—This study was part of the Dunedin Multidisciplinary Health and Development Study (DMHDS), which is a longitudinal study of the health, development, and behaviour of a cohort of young New Zealanders.

Method—At the age 21 assessment DMHDS study members were asked to report serious injury and motor vehicle traffic crashes experienced over the previous three years. The self reported injuries were compared with the New Zealand Health Information Service (NZHIS) public hospital discharge file to determine the completeness of the self reported data. The traffic crashes were compared with the police traffic crash reports to determine the accuracy of self reported crash details.

Results—Twenty five (86%) of the 29 unintentional injuries, six (67%) of the nine assaults, and one (14%) of the six self inflicted injuries on the NZHIS file were self reported. The level of agreement between the self reported crash details and those recorded on the traffic crash report was high.

Conclusions—The results show that self reports can be a useful and valid source of injury and crash data.
Alcohol and other psychoactive drugs in trauma patients aged 10–14 years
Authors: Li Guohua , Chanmugam Arjun , Rothman Richard , DiScala Carla , Paidas Charles N , Kelen Gabor D
Published: December 2008

Objective—To examine the prevalence of alcohol and/or other psychoactive drugs, such as marijuana and cocaine (AODs), involved in preteen trauma patients.

Methods—Toxicological testing results were analyzed for 1356 trauma patients aged 10–14 years recorded in the National Pediatric Trauma Registry for the years 1990–95.

Results—Of the 1356 patients who received toxicological screening at the time of admission, 116 (9%) were positive for AODs. AOD involvement increased with age. Patients with pre-existing mental disorders were nearly three times as likely as other patients to be AOD positive (23%v8%, p<0.01). AOD involvement was more prevalent in intentional injuries and in injuries that occurred at home.

Conclusions—AODs in preteen trauma are of valid concern, in particular among patients with mental disorders or intentional injuries. The role of AODs in childhood injuries needs to be further examined using standard screening instruments and representative study samples.
Unintentional injury mortality in children: a priority for middle income countries in the advanced stage of epidemiological transition
Authors: Plitponkarnpim Adisak , Andersson Ragnar , Jansson Bjarne , Svanström Leif
Published: December 2008

Objectives—To examine the relationship between the magnitude, and the relative importance of unintentional child injury mortality with socioeconomic development, and to conceptualise the dynamic changes in injury mortality within the framework of epidemiological transition.

Design—Ecological cross sectional study using data on 51 countries.

Main outcome measures—The relationship between total mortality rates, unintentional injury mortality rates, and percentage in children 1–14 years of age with gross national product (GNP) per capita.

Results—Unintentional injury mortality rates in children were negatively correlated with GNP per capita. However, by categorising the data, we found some areas of non-correlation: in children 5–14 years in low income versus lower middle income countries, and in all age and gender groups in lower high income versus higher high income countries. A high percentage of total deaths due to injuries was clearest in the lower middle income countries in all age and gender groups.

Conclusions—The changes in child injury mortality in relation to socioeconomic development could be conceptualised as three stages: a stage of high magnitude; a stage of high priority; and a stage of improvement. Most middle income countries are in the high priority stage where both injury mortality rates and injury percentage of total deaths are high.
Personal and family predictors of children's medically attended injuries that occurred in the home
Authors: Mott Joshua A
Published: December 2008

Objective—This study examined the independent contributions of demographic, behavioral, and environmental antecedents of pediatric medically attended injuries that occurred in the home.

Setting—Two thousand and thirty six American children aged 4–12 in 1988 were drawn from the National Longitudinal Survey of Youth.

Method—Multiple logistic regression was used to examine whether having a medically attended injury that occurred in the home in 1990 was related to environmental, behavioral, and demographic indicators measured in 1988. To account for individual differences in access to care, results were stratified within samples of children that had, and had not, demonstrated a prior ability to access the medical care system for injury treatment.

Results—Among children whodid notaccess the medical care system for injury treatment in 1988, measures of home environmental risk factors did not distinguish those injured at home from those not injured at home in 1990. However, among children whodidaccess the medical care system for injury treatment in 1988, indicators of “dark” (relative risk 4.68, p=0.019) and “cluttered” (relative risk 4.31, p=0.038) home environments became significantly and independently associated with home injuries in 1990.

Conclusion—If not accounted for in data collection or analyses, individual differences in non-financial barriers to medical care may lead to an underestimation of the influences of important home environmental risk factors for medically attended injuries.
Fit of bicycle safety helmets and risk of head injuries in children
Authors: Rivara Frederick P , Astley Susan J , Clarren Sterling K , Thompson Diane C , Thompson Robert S
Published: December 2008

Background—Although bicycle helmets are effective in preventing head and brain injury, some helmeted individuals nevertheless sustain head injury. One of the possible reasons may be poor fit of the helmet on the head. This study was undertaken to examine the relationship between helmet fit and risk of injury.

Methods—1718 individuals who were helmeted riders in a crash were queried on helmet fit and position. A sample of 28 children 2–14 years of age who sustained a head injury while wearing a bicycle helmet and 98 helmeted individuals of the same age treated in the same hospital emergency departments for injuries other than to the head, underwent anthropometric measurements of helmet fit. Measurements were made of the child's head, the helmet, and on a cast made of the child's head.

Results—Individuals whose helmets were reported to fit poorly had a 1.96-fold increased risk of head injury compared with those whose helmets fit well. Children with head injuries had helmets which were significantly wider than their heads compared with children without head injuries. Helmet fit was poorer among males and among younger children.

Conclusions—Poor fit of helmets may be associated with an increased risk of head injury in children, especially in males. Helmets may not be designed to provide optimal protection.
Factors affecting motorcycle helmet use in the population of Greater Athens, Greece
Authors: Skalkidou Alkistis , Petridou Eleni , Papadopoulos Fotios C , Dessypris Nick , Trichopoulos Dimitrios
Published: December 2008

Objectives—Helmet use is the best preventive measure available against two wheel motorized vehicle (TWMV) related head injuries. In some countries, however, helmets are used only by a minority of TWMV riders. In collaboration with the Road Traffic Police Department, an inspection survey was undertaken to assess the prevalence and to determine predictors of helmet use.

Setting—The Greater Athens area, Greece, during July and August 1998.

Methods—A total of 982 TWMVs were stopped, 349 of which had two riders (36%). All riders were interviewed by staff members of the Centre for Research and Prevention of Injuries among the Young.

Results—The average prevalence of helmet use was 20.2%. It ranged from 9.7% on small suburban roads to 50.8% on highways. Prevalence of use was significantly lower during the weekend days and at night. Women were significantly more likely to wear a helmet and, controlling for gender, drivers were significantly more likely to be helmet users. Riders of more powerful TWMVs and passengers, who themselves had a TWMV driving license, were helmet users more frequently. Among non-users, the majority (46%) indicated that “the helmet made them feel uncomfortable”, particularly in warm weather, whereas 18% claimed that there was little need for a helmet in low speed riding.

Conclusions—A multipronged campaign is urgently needed in Greece to increase the prevalence of helmet use by TWMV riders. The campaign should include not only police enforcement but also initiatives to make helmets more convenient to wear and less expensive.
Young guns: an empirical study of persons who use a firearm in a suicide or a homicide
Authors: Sorenson Susan B , Berk Richard A
Published: December 2008

Objectives—The purpose of this investigation was to identify population groups at highest risk of using a firearm in a fatal incident.

Setting—Los Angeles County (California, USA).

Methods—Data were gathered from vital statistics reports and law enforcement records on the characteristics of suicide victims (n = 4799) and homicide suspects (n = 5369) from 1990 through 1994. Logistic regression was used to identify characteristics of the actor/perpetrator that were associated with firearm use.

Results—Persons less than 21 years old and males were more likely to use a firearm to kill themselves or someone else. Even when their other demographic attributes and characteristics of the incident itself were taken into consideration, persons under the age of 18 were substantially more likely than those 21 or more years old to use a firearm in the commission of a homicide (adjusted odds ratio = 2.59). Asians were less likely than white people to use a firearm in the commission of a suicide, whereas black people, Hispanics, and Asians were more likely than whites to use a firearm in the commission of a homicide.

Conclusions—The US enacts and enforces some policies differentially by age. These data support the idea that such an approach may be warranted when addressing fatalities associated with the use of a firearm. Of particular interest, given minimum age requirements for firearm purchases, is the source of the weapons themselves.
Beliefs about the risks of guns in the home: analysis of a national survey
Authors: Howard Kim Ammann , Webster Daniel W , Vernick Jon S
Published: December 2008

Objectives—While epidemiological evidence suggests homes with guns are more likely to be the site of a suicide or homicide than homes without guns, the public's perception of these risks remains unknown. This study assesses the prevalence of the belief that homes with guns are safer than homes without guns, and factors associated with this belief.

Methods—Telephone interviews were conducted with a random sample of 4138 registered voters in urban areas in the US. Multinomial logistic regression was used to assess correlates of beliefs about the safety of keeping a gun in the home.

Results—Twenty nine per cent of respondents believed keeping a gun in the home makes the home more safe, 40% said less safe, 23% said it depends, and 9% were unsure. The belief that a home is more safe with a gun was associated with being male, young, completing 12 years or fewer of education, having no children living at home, Republican party affiliation, and low levels of trust in the police for protection. Prior exposure to violence and fear of victimization were not associated with the outcome.

Conclusions—Findings may increase understanding about the public's perception of the risk in keeping guns in the home and assist educational efforts to decrease the risk of these injuries.
Pre-hospital emergency medical services: a population based study of pediatric utilization
Authors: Suruda Anthony , Vernon Donald D , Reading James , Cook Larry , Nechodom Patricia , Leonard Daniel , Dean J Michael
Published: December 2008

Objectives—To examine emergency medical services (EMS) usage by children in one state.

Methods—Dispatch of an EMS vehicle in response to a call in the US is referred to as a “run”. Runs for Utah for 1991–92 were linked to corresponding hospital records. Abbreviated injury severity scores (AISs) were assigned using ICDMAP-90 software.

Results—For the two year period there were at least 15 EMS runs per 100 children per year, with incomplete reporting from rural areas. EMS response and scene times were similar for all age groups, but interventions were less frequent for children under 5 years of age. When the principal AIS region of injury was the head, neck, or face, cervical immobilization was less frequent for children less than 5 years of age (54%) than for older children (76%) and immobilization was associated with improved outcome, using the crude measure of lower hospital charges. There was a similar association between splinting of upper extremity fractures and reduced hospital charges. Both associations did not appear to be due to differences in injury severity.

Conclusions—The majority of EMS use by children is for trauma. Children less than 5 years of age are less likely to have an EMS intervention than older children. Whether the lower frequency of interventions is due to the lack of properly sized equipment on the vehicle, or to other factors, is undetermined.
Childhood finger injuries and safeguards
Authors: Doraiswamy N V
Published: December 2008

Objective—To understand the epidemiology, sites, and mechanism of finger injuries in children and to consider safety measures.

Setting—Accident and emergency department of a children's hospital in Glasgow.

Methods—A prospective study was carried out with a specifically designed questionnaire. Altogether 283 children presenting with isolated finger injuries were identified over six months. Available safety measures to avoid or reduce damage from such injuries were considered.

Results—Finger injuries were common (38%) in those under 5 years. Most of these occurred at home (59%), commonly (48%) because of jamming between two closeable opposing surfaces, and mostly (79%) in doors at home and school. The doors were commonly (85%) closed by someone and often (60%) by a child. Sixteen (6%) were treated for amputation.

Conclusion—Finger injuries are common, especially at the preschool age, and are mostly caused by jammed fingers in doors, at home. Safeguards should be considered according to location, like home or institutions, and expense.
Under representation of morbidity from paediatric bicycle accidents by official statistics—a need for data collection in the accident and emergency department
Authors: Leonard P A , Beattie T F , Gorman D R
Published: December 2008

Objectives—To determine the accuracy of currently available data on bicycle related injuries in children.

Setting—A paediatric accident and emergency (A&E) department which annually treats approximately 30 000 new patients under the age of 13 years.

Methods—Data on all attendances with bicycle related injuries over a four week period were compared with that currently available from police road traffic accident data (Stats 19) and theInternational Classification of Diseases, 10th revision, hospital discharge coding.

Results—Eighty six children attended the A&E department. Only two bicycle related injuries were identified from Stats 19, and 10 from hospital discharge data.

Conclusion—Currently available official data do not give an accurate representation of the incidence of bicycle related injuries in children. If health promotion measures are to be assessed properly data collection needs to be improved.
Using a diary to record near misses and minor injuries—which method of administration is best?
Authors: Marsh Patricia , Kendrick Denise
Published: December 2008

Objectives—To determine the effect of different methods of administering a diary to collect information from parents on near miss and minor injuries on responses, completeness and accuracy, the number of incidents reported, the effect of a financial incentive on response, and the cost of administering each method.

Setting—The study was set within the context of a cluster randomised controlled trial of injury prevention in 36 practices in Nottingham.

Methods—The study population comprised the 1594 parents who responded to the baseline questionnaire. Parents were allocated systematically to one of four groups: postal administration, with and without financial incentive, telephone administration, with and without financial incentive (102 in each group). A clinic visit method with and without financial incentive (50 in each group) was also used.

Results—A significant trend was found, with decreasing response rates with increasing degree of contact with the parent, such that administering the diary in the clinic had the lowest response (χ2for trend = 5.54, 1 df, p = 0.02). Offering a financial incentive increased responses from 47% to 59% (χ2=5.78, 1 df, p = 0.016). The most complete recording was found in the diaries handed out at clinic visits. Importantly, parents were accurate in their recording of near miss and minor injuries, suggesting they understood the differences between the two types of incident. Postal methods were the least expensive method of administering the diary in terms of average cost per returned diary. Using a financial incentive resulted in a lower cost per returned diary for telephone and clinic visit methods.

Conclusions—Parents can accurately and reliably complete diaries recording near miss and minor injuries occurring to their preschool children. More work is needed to investigate methods of increasing response. Postal diaries achieve the highest response but have the least complete recording of data. Diaries administered through child health clinics were most complete but achieved the lowest response. The administration method chosen in future work should be influenced both by the response and completeness of recording that is required by the research.
SEARCHING EXACT SOLUTIONS FOR COMPACT STARS IN BRANEWORLD: A CONJECTURE
Authors: OVALLE J.
Published: December 2008

In the context of the braneworld, a method to find consistent solutions to Einstein's field equations in the interior of a spherically symmetric, static and non-uniform stellar distribution with Weyl stresses is developed. This method, based on the fact that any braneworld stellar solution must have the general relativity solution as a limit, produces a constraint which reduces the degrees of freedom on the brane. Hence the nonlocality and non-closure of the braneworld equations can be overcome. The constraint found is physically interpreted as a necessary condition to regain general relativity, and a particular solution for it is used to find an exact and physically acceptable analytical internal solution to no-uniform stellar distributions on the brane. It is shown that such an exact solution is possible due to the fact that bulk corrections to pressure, density and a metric component are a null source of anisotropic effects on the brane. A conjecture is proposed regarding the possibility of finding physically relevant exact solutions to non-uniform stellar distributions on the brane.
UNIFIED FIRST LAW AND THERMODYNAMICS OF DYNAMICAL BLACK HOLE IN n-DIMENSIONAL VAIDYA SPACETIME
Authors: REN JI-RONG , LI RAN
Published: December 2008

As a simple but important example of dynamical black hole, we analyze the dynamical black hole in n-dimensional Vaidya spacetime in detail. We investigated the thermodynamics of field equation in n-dimensional Vaidya spacetime. The unified first law was derived in terms of the methods proposed by Hayward. The first law of dynamical black hole was obtained by projecting the unified first law along the trapping horizon. The second law of dynamical black hole is also discussed.
COALITION FORMATION IN STRADDLING STOCK FISHERIES: A PARTITION FUNCTION APPROACH
Authors: PINTASSILGO PEDRO , LINDROOS MARKO
Published: December 2008

In this paper the management of straddling fish stocks is approached through a coalition game in partition function form. A two-stage game is applied, assuming ex ante symmetric players and the classical Gordon-Schaefer bioeconomic model. It is shown that the game is characterized by positive externalities — the merger of coalitions increases the payoffs of players who belong to other coalitions. A key result is that, apart from the case of two players, the grand coalition is not a Nash equilibrium outcome. Furthermore, in the case of three or more players the only Nash equilibrium coalition structure is the one formed by singletons. The results indicate that the prospects of cooperation in straddling stock fisheries are low if players can free ride cooperative agreements. Thus, in order to protect cooperation, under the aegis of regional fishery management organizations, unregulated fishing must be prevented.
Adenosine A1 and A2a receptors modulate insulinemia, glycemia, and lactatemia in fetal sheep
Authors: Maeda Takatsugu , Koos Brian J.
Published: December 2008

Adenosine A1 and A2A receptor subtypes modulate metabolism in adult mammals. This study was designed to determine the role of these receptors in regulating plasma levels of insulin, glucose, and lactate in 20 chronically catheterized fetal sheep (>0.8 term). In normoxic fetuses (PaO2 ∼24 Torr), systemic blockade of A1 receptors with DPCPX ( n = 6) increased plasma concentrations of insulin, glucose, and lactate, but antagonism of A2A receptors with ZM-241385 ( n = 5) had no significant effects. Intravascular administration of adenosine ( n = 9) reduced insulin concentrations and elevated glucose and lactate levels. DPCPX ( n = 6) augmented the glycemic and lactatemic responses of adenosine. In contrast, ZM241385 ( n = 5) virtually abolished adenosine-induced hyperglycemia and hyperlactatemia. Isocapnic hypoxia (PaO2 ∼13 Torr) suppressed insulinemia and enhanced glycemia and lactatemia, but only the hyperglycemia was blunted by blockade of A1 ( n = 6) or A2A ( n = 6) receptors. We conclude that 1) endogenous adenosine via A1 receptors depresses plasma concentrations of insulin, glucose, and lactate; 2) exogenous adenosine via A2A receptors increases glucose and lactate levels, but these responses are dampened by stimulation of A1 receptors; and 3) hypoxia, which increases endogenous adenosine concentrations, induces hyperglycemia that is partly mediated by activation of A1 and A2A receptors. We predict that adenosine, via A1 receptors, facilitates at least 12% of glucose uptake and utilization in normoxic fetuses.
Ghrelin modulates electrical activity of area postrema neurons
Authors: Fry Mark , Ferguson Alastair V.
Published: December 2008

Ghrelin, a peptide hormone secreted from the stomach, is known to have a potent appetite-stimulating activity. Recently, it has been shown that area postrema (AP), a caudal brain stem center that lacks a blood-brain barrier, is a key site of activity for ghrelin in stimulating appetite and regulating pancreatic protein secretion. In this study, we have examined the ability of ghrelin to regulate the electrical activity of area postrema neurons using patch-clamp electrophysiology. Using current-clamp configuration, we found that at a concentration of 10 nM, ghrelin caused inhibition in 19% of neurons tested, while a further 19% were excited by similar application of ghrelin. The remaining 62% of AP neurons were insensitive to ghrelin. These effects were concentration dependent, with an apparent EC50 of 1.9 nM. Voltage-clamp recordings revealed that ghrelin caused a potentiation of voltage-gated K+ currents in neurons that exhibited a hyperpolarization and a potentiation of a depolarizing nonspecific cation current (NSCC) in those neurons that exhibited a depolarization of membrane potential. These are the first data showing that ghrelin exerts a direct effect on electrical activity of AP neurons and supports the notion that ghrelin can act via the AP to regulate energy homeostasis.
Ventromedial nucleus neurons are less sensitive to leptin excitation in rats bred to develop diet-induced obesity
Authors: Irani Boman G. , Le Foll Christelle , Dunn-Meynell Ambrose A. , Levin Barry E.
Published: December 2008

Maternal obesity accentuates offspring obesity in dams bred to develop diet-induced obesity (DIO) on a 31% fat, high energy (HE) diet but has no effect on offspring of diet-resistant (DR) dams. Only DIO dams became obese on HE diet when they and DR dams were fed 5% fat chow or HE diets throughout gestation and lactation. Leptin sensitivity of dissociated arcuate (ARC) and ventromedial (VMN) hypothalamic nucleus neurons from the 3- to 4-wk-old offspring was assessed using fura-2 calcium imaging to monitor leptin-induced changes in intracellular calcium ([Ca2+]i) as an index of neuronal activity. At 0.1, 1, 10 fmol/l leptin, ∼4 times more VMN and ARC neurons were excited than inhibited by leptin. In the VMN, leptin excited up to 41% fewer neurons, and these excited neurons were less sensitive to increasing doses of leptin in DIO compared with DR offspring. Also, maternal HE diet intake decreased the percentage of leptin-excited VMN neurons in both DIO and DR offspring and decreased the percentage of leptin-inhibited VMN neurons by 36% only in DIO offspring. In the ARC, there were no genotype or maternal diet effects on the percentage of ARC neurons excited by leptin. However, those DR neurons that were leptin excited were more sensitive to leptin than were those from DIO offspring. These data suggest that reduced responsiveness of DIO VMN neurons to leptin's excitatory effects may be an important contributing factor to the reduced anorectic and thermogenic leptin responsiveness of DIO rats in vivo.
Nectin proteins are expressed at early stages of nephrogenesis and play a role in renal epithelial cell morphogenesis
Authors: Brakeman Paul R. , Liu Kathleen D. , Shimizu Kazuya , Takai Yoshimi , Mostov Keith E.
Published: December 2008

Development of the nephron requires conversion of the metanephric mesenchyme into tubular epithelial structures with specifically organized intercellular junctions. The nectin proteins are a family of transmembrane proteins that dimerize to form intercellular junctional complexes between epithelial cells. In this study, we demonstrate that nectin junctions appear during the earliest stages of epithelial cell morphogenesis in the murine nephron concurrently with the transition of mesenchymal cells into epithelial cells. We have defined the role of nectin during epithelial cell morphogenesis by studying nectin in a three-dimensional culture of Madin-Darby canine kidney (MDCK) cells. In a three-dimensional culture of MDCK cells grown in purified type 1 collagen, expression of a dominant negative form of nectin causes disruption of the formation of cell polarity and disruption of tight junction (TJ) formation, as measured by zonula occludens-1 (ZO-1) localization. In MDCK cells cultured in Matrigel, exogenous expression of nectin-1 causes disruption of normal epithelial cell cyst formation and decreased apoptosis. These data demonstrate that nectins play an important role in normal epithelial cell morphogenesis and may play a role in mesenchymal-to-epithelial transition during nephrogenesis by providing an antiapoptotic signal and promoting the formation of TJs and cell polarity.
Electrotonic vascular signal conduction and nephron synchronization
Authors: Marsh Donald J. , Toma Ildiko , Sosnovtseva Olga V. , Peti-Peterdi Janos , Holstein-Rathlou Niels-Henrik
Published: December 2008

Tubuloglomerular feedback (TGF) and the myogenic mechanism control afferent arteriolar diameter in each nephron and regulate blood flow. Both mechanisms generate self-sustained oscillations, the oscillations interact, TGF modulates the frequency and amplitude of the myogenic oscillation, and the oscillations synchronize; a 5:1 frequency ratio is the most frequent. TGF oscillations synchronize in nephron pairs supplied from a common cortical radial artery, as do myogenic oscillations. We propose that electrotonic vascular signal propagation from one juxtaglomerular apparatus interacts with similar signals from other nephrons to produce synchronization. We tested this idea in tubular-vascular preparations from mice. Vascular smooth muscle cells were loaded with a fluorescent voltage-sensitive dye; fluorescence intensity was measured with confocal microscopy. Perfusion of the thick ascending limb activated TGF and depolarized afferent arteriolar smooth muscle cells. The depolarization spread to the cortical radial artery and other afferent arterioles and declined with distance from the perfused juxtaglomerular apparatus, consistent with electrotonic vascular signal propagation. With a mathematical model of two coupled nephrons, we estimated the conductance of nephron coupling by fitting simulated vessel diameters to experimental data. With this value, we simulated nephron pairs to test for synchronization. In single-nephron simulations, the frequency of the TGF oscillation varied with nephron length. Coupling nephrons of different lengths forced TGF frequencies of both pair members to converge to a common value. The myogenic oscillations also synchronized, and the synchronization between the TGF and the myogenic oscillations showed an increased stability against parameter perturbations. Electronic vascular signal propagation is a plausible mechanism for nephron synchronization. Coupling increased the stability of the various oscillations.
Reflex Control of the Human Inner Ear: A Half-Octave Offset in Medial Efferent Feedback That Is Consistent With an Efferent Role in the Control of Masking
Authors: Lilaonitkul Watjana , Guinan John J.
Published: December 2008

The high sensitivity and frequency selectivity of the mammalian cochlea is due to amplification produced by outer hair cells (OHCs) and controlled by medial olivocochlear (MOC) efferents. Data from animals led to the view that MOC fibers provide frequency-specific inhibitory feedback; however, these studies did not measure intact MOC reflexes. To test whether MOC inhibition is primarily at the frequency that elicits the MOC activity, acoustically elicited MOC effects were quantified in humans by the change in otoacoustic emissions produced by 60-dB SPL tone and half-octave-band noise elicitors at different frequencies relative to a 40-dB SPL, 1-kHz probe tone. On average, all elicitors produced MOC effects that were skewed (elicitor frequencies -1 octave below the probe produced larger effects than those -1 octave above). The largest MOC effects were from elicitors below the probe frequency for contra- and bilateral elicitors but were from elicitors centered at the probe frequency for ipsilateral elicitors. Typically, ipsilateral elicitors produced larger effects than contralateral elicitors and bilateral elicitors produced effects near the ipsi+contra sum. Elicitors at levels down to 30-dB SPL produced similar patterns. Tuning curves (TCs) interpolated from these data were V-shaped with Q10s ∼2. These are sharper than MOC-fiber TCs found near 1 kHz in cats and guinea pigs. Because cochlear amplification is skewed (more below the best frequency of a cochlear region), these data are consistent with an anti-masking role of MOC efferents that reduces masking by reducing the cochlear amplification seen at 1 kHz.
Transcriptional and functional differences in stem cell populations isolated from extraocular and limb muscles
Authors: Pacheco-Pinedo Eugenia C. , Budak Murat T. , Zeiger Ulrike , Jørgensen Louise Helskov , Bogdanovich Sasha , Schrøder Henrik Daa , Rubinstein Neal A. , Khurana Tejvir S.
Published: December 2008

The extraocular muscles (EOMs) are a distinct muscle group that displays an array of unique contractile, structural, and regenerative properties. They also have differential sensitivity to certain diseases and are enigmatically spared in Duchenne muscular dystrophy (DMD). The EOMs are so distinct from other skeletal muscles that the term “allotype” has been coined to highlight EOM group-specific properties. We hypothesized that increased and distinct stem cells may underlie the continual myogenesis noted in EOM. The side population (SP) stem cells were isolated and studied. EOMs had 15× higher SP cell content compared with limb muscles. Expression profiling revealed 348 transcripts that define the EOM-SP transcriptome. Over 92% of transcripts were SP specific, because they were absent in previous whole muscle microarray studies. Cultured EOM-SP cells revealed superior in vitro proliferative capacity. Finally, assays of the committed progenitors or satellite cells performed on myofibers isolated from EOM and limb muscles independently validated the increased proliferative capacity of these muscles. We suggest a model in which unique EOM stem cells contribute to the continual myogenesis noted in EOM and consistent with a role for their sparing in DMD. We believe the greater numbers of stem cells, their unique transcriptome, the greater proliferative capacity of EOM stem cells, and the greater number of satellite cells also offer clues for novel cell-based therapeutic strategies.
Mean Amplitudes of Vibration of the IF8 − Anion
Authors: Baran Enrique J.
Published: December 2008

The mean amplitudes of vibration of the interesting IF8 − anion (D4d‐symmetry), containing iodine (VII), were calculated from known spectroscopic and structural data in the temperature range between 0 and 1000 K. The results are discussed in comparison with those of related species.
On the Global Asymptotic Stability of Switched Linear Time‐Varying Systems with Constant Point Delays
Authors: de la Sen M. , Ibeas A.
Published: December 2008

This paper investigates the asymptotic stability of switched linear time‐varying
systems with constant point delays under not very stringent conditions on the matrix functions
of parameters. Such conditions are their boundedness, the existence of bounded time derivatives
almost everywhere, and small amplitudes of the appearing Dirac impulses where
such derivatives do not exist. It is also assumed that the system matrix for zero delay is stable
with some prescribed stability abscissa for all time in order to obtain sufficiency‐type conditions of asymptotic stability dependent on the delay sizes. Alternatively, it is assumed
that the auxiliary system matrix defined for all the delayed system matrices being zero is
stable with prescribed stability abscissa for all time to obtain results for global asymptotic
stability independent of the delays. A particular subset of the switching instants is the so‐called
set of reset instants where switching leads to the parameterization to reset to a value
within a prescribed set.
Bandwidth Improvement of EBG Resonator Antennas Using Double‐Layer FSS
Authors: Moustafa Lina , Jecko Bernard
Published: December 2008

A double‐layer frequency selective surface (FSS) is proposed as a means to enhance the bandwidth of an electromagnetic band gap (EBG) resonator antenna. Due to its inverted reflection phase variation and its wide selectivity bandwidth, the structure used in the radiating wall of the resonator allows increasing the radiating bandwidth of the last one. The resonator is fed by a patch feeding source placed inside the cavity at the proximity of its metallic ground. The antenna bandwidth is significantly improved by virtue of employing the double‐layer FSS. Modelled results of an antenna working at 5 GHz are shown.