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1.
Health Phys ; 123(5): 360-364, 2022 11 01.
Article in English | MEDLINE | ID: mdl-35951339

ABSTRACT

ABSTRACT: A housing development of 87 new homes on approximately 300 acres of former farm land was found to have 19 homes with basement radon-222 ( 222 Rn) concentrations greater than 37,000 Bq m -3 , with the highest recorded result to date being 648,000 +/- 1,031 Bq m -3 , based upon the diffusion barrier charcoal canister result. The US Environmental Protection Agency (EPA) Action Level for 222 Rn is 148 Bq m -3 . This single-family housing development is in the southeast corner of Lehigh County, Pennsylvania, about 58 km northwest of Philadelphia, in a geologic unit known as the Epler Formation. Radon testing in homes in this development began in the fall of 2014 and is now complete. Initial testing consisted of charcoal canisters mailed to homeowners. Subsequent testing in newly built homes consisted of testing prior to occupancy. This testing was quite extensive, with continuous radon monitors, passive radon monitors, and grab sampling for radon gas and progeny in the basement and on the first floor of each home as well as gamma surveys in the basement, on the first and second floors, and outside of each home. All but one of the new houses in this development had passive radon resistant features installed during the construction phase. In all cases, fans were added to the passive systems to make them active systems, which were needed to control these extremely high radon levels. Additional radon mitigation work such as adding additional suction points was also needed in several homes to reduce levels to below EPA guidelines. The unique geology and high 226 Ra soil concentrations in this specific area are the causes of these extremely high radon levels. Radon measurement data both inside these homes and in the outdoor ambient air, as well as 238 U and 222 Ra rock and soil concentrations, are presented.


Subject(s)
Air Pollutants, Radioactive , Air Pollution, Indoor , Radon , Air Pollutants, Radioactive/analysis , Air Pollution, Indoor/analysis , Charcoal , Housing , Pennsylvania , Radon/analysis , Soil
2.
Space Sci Rev ; 218(1): 3, 2022.
Article in English | MEDLINE | ID: mdl-35153338

ABSTRACT

EUSO-Balloon is a pathfinder for JEM-EUSO, the mission concept of a spaceborne observatory which is designed to observe Ultra-High Energy Cosmic Ray (UHECR)-induced Extensive Air Showers (EAS) by detecting their UltraViolet (UV) light tracks "from above." On August 25, 2014, EUSO-Balloon was launched from Timmins Stratospheric Balloon Base (Ontario, Canada) by the balloon division of the French Space Agency CNES. After reaching a floating altitude of 38 km, EUSO-Balloon imaged the UV light in the wavelength range ∼290-500 nm for more than 5 hours using the key technologies of JEM-EUSO. The flight allowed a good understanding of the performance of the detector to be developed, giving insights into possible improvements to be applied to future missions. A detailed measurement of the photoelectron counts in different atmospheric and ground conditions was achieved. By means of the simulation of the instrument response and by assuming atmospheric models, the absolute intensity of diffuse light was estimated. The instrument detected hundreds of laser tracks with similar characteristics to EASs shot by a helicopter flying underneath. These are the first recorded laser tracks measured from a fluorescence detector looking down on the atmosphere. The reconstruction of the direction of the laser tracks was performed. In this work, a review of the main results obtained by EUSO-Balloon is presented as well as implications for future space-based observations of UHECRs.

3.
Phys Rev Lett ; 109(6): 062002, 2012 Aug 10.
Article in English | MEDLINE | ID: mdl-23006259

ABSTRACT

We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.

4.
Sci Total Environ ; 409(20): 4257-68, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-21782213

ABSTRACT

Dental amalgam is 50% metallic mercury (Hg) by weight and Hg vapour continuously evolves from in-place dental amalgam, causing increased Hg content with increasing amalgam load in urine, faeces, exhaled breath, saliva, blood, and various organs and tissues including the kidney, pituitary gland, liver, and brain. The Hg content also increases with maternal amalgam load in amniotic fluid, placenta, cord blood, meconium, various foetal tissues including liver, kidney and brain, in colostrum and breast milk. Based on 2001 to 2004 population statistics, 181.1 million Americans carry a grand total of 1.46 billion restored teeth. Children as young as 26 months were recorded as having restored teeth. Past dental practice and recently available data indicate that the majority of these restorations are composed of dental amalgam. Employing recent US population-based statistics on body weight and the frequency of dentally restored tooth surfaces, and recent research on the incremental increase in urinary Hg concentration per amalgam-filled tooth surface, estimates of Hg exposure from amalgam fillings were determined for 5 age groups of the US population. Three specific exposure scenarios were considered, each scenario incrementally reducing the number of tooth surfaces assumed to be restored with amalgam. Based on the least conservative of the scenarios evaluated, it was estimated that some 67.2 million Americans would exceed the Hg dose associated with the reference exposure level (REL) of 0.3 µg/m(3) established by the US Environmental Protection Agency; and 122.3 million Americans would exceed the dose associated with the REL of 0.03 µg/m(3) established by the California Environmental Protection Agency. Exposure estimates are consistent with previous estimates presented by Health Canada in 1995, and amount to 0.2 to 0.4 µg/day per amalgam-filled tooth surface, or 0.5 to 1 µg/day/amalgam-filled tooth, depending on age and other factors.


Subject(s)
Dental Amalgam/analysis , Environmental Exposure/analysis , Mercury/analysis , Adolescent , Adult , Aged , Child , Child, Preschool , Creatinine/urine , Dental Amalgam/chemistry , Dental Amalgam/toxicity , Dental Restoration, Permanent/statistics & numerical data , Environmental Exposure/adverse effects , Feces/chemistry , Humans , Mercury/toxicity , Mercury/urine , Middle Aged , Population Surveillance , Risk , Tissue Distribution , United States , Young Adult
5.
Phys Rev Lett ; 104(9): 091101, 2010 Mar 05.
Article in English | MEDLINE | ID: mdl-20366976

ABSTRACT

We describe the measurement of the depth of maximum, X{max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10;{18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{-21}{+35}) g/cm{2}/decade below 10{18.24+/-0.05} eV, and (24+/-3) g/cm{2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

6.
Rev Neurol (Paris) ; 166(6-7): 565-73, 2010.
Article in French | MEDLINE | ID: mdl-20116812

ABSTRACT

INTRODUCTION: Hemiplegic (or spastic unilateral) cerebral palsy accounts for about 30% of all cases of cerebral palsy. With a population prevalence of 0.6 per 1000 live births, it is the most common type of cerebral palsy among term-born children and the second most common type after diplegia among preterm infants. STATE OF THE ART: Many types of prenatal and perinatal brain injury can lead to congenital hemiplegia and brain MRI is the most useful tool to classify them with accuracy and to provide early prognostic information. Perinatal arterial ischemic stroke thus appears as the leading cause in term infants, whereas encephalopathy of prematurity is the most common cause in premature babies. Other causes include brain malformations, neonatal sinovenous thrombosis, parenchymal hemorrhage (for example due to coagulopathy or alloimmune thrombocytopenia) and the more recently described familial forms of porencephaly associated with mutations in the COL4A1 gene. PERSPECTIVES: In adjunction with pharmacologic treatment (botulinium neurotoxin injection), new evidence-based rehabilitational interventions, such as constraint-induced movement therapy and mirror therapy, are increasingly being used.


Subject(s)
Cerebral Palsy , Hemiplegia , Algorithms , Botulinum Toxins, Type A/therapeutic use , Brain/abnormalities , Cerebral Palsy/diagnosis , Cerebral Palsy/epidemiology , Cerebral Palsy/rehabilitation , Exercise Therapy , Fetal Diseases , Hemiplegia/diagnosis , Hemiplegia/epidemiology , Hemiplegia/rehabilitation , Humans , Infant, Newborn , Infant, Premature , Infant, Premature, Diseases/epidemiology , Muscle Spasticity/etiology , Physical Therapy Modalities , Prevalence , Risk Factors , Stroke/complications , Stroke/embryology
7.
Phys Rev Lett ; 101(6): 061101, 2008 Aug 08.
Article in English | MEDLINE | ID: mdl-18764444

ABSTRACT

The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.

8.
Phys Rev Lett ; 100(21): 211101, 2008 May 30.
Article in English | MEDLINE | ID: mdl-18518595

ABSTRACT

The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV.

9.
Science ; 318(5852): 938-43, 2007 Nov 09.
Article in English | MEDLINE | ID: mdl-17991855

ABSTRACT

Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above 6 x 10(19) electron volts and the positions of active galactic nuclei (AGN) lying within approximately 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest-energy particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.

10.
J Pediatr Hematol Oncol ; 28(4): 237-40, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16679922

ABSTRACT

Hemangiopericytoma (HPC) is a soft-tissue neoplasm composed of proliferating capillary pericytes. It has variable and unpredictable malignancy and most commonly occurs in the fifth or sixth decade of life. Diagnosis is based on the histological aspect. HPC is exceedingly rare in childhood. In both adults and children, curative surgery is the most important predictor of survival. The place of chemotherapy in the treatment of HPC is not well established. We describe a case of adult-type metastatic HPC of the thigh in a 13-year-old boy. The response to neoadjuvant chemotherapy was excellent, and local control of this initially unresectable tumor was achieved without radiation therapy or mutilating surgery. The child is alive and well and has had 8 years of follow-up after treatment.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Femoral Neoplasms/surgery , Hemangiopericytoma/drug therapy , Hemangiopericytoma/surgery , Lung Neoplasms/secondary , Adolescent , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Chemotherapy, Adjuvant , Combined Modality Therapy , Dacarbazine/administration & dosage , Doxorubicin/administration & dosage , Femoral Neoplasms/diagnostic imaging , Femoral Neoplasms/drug therapy , Femoral Neoplasms/pathology , Hemangiopericytoma/diagnostic imaging , Hemangiopericytoma/pathology , Humans , Ifosfamide/administration & dosage , Lung Neoplasms/drug therapy , Male , Mesna/administration & dosage , Time Factors , Tomography, X-Ray Computed , Treatment Outcome
12.
S Afr Med J ; 95(8): 591-4, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16201002

ABSTRACT

INTRODUCTION: Firearms, the leading external cause of non-natural deaths in South Africa, claim approximately 15,000 lives annually. Up to 127,000 firearm-injured victims seek state health care assistance per annum. The fiscal burden of treating these injuries is not known. METHODS: All serious abdominal firearm-related injuries (requiring admission to hospital and emergency surgery) presenting to a state hospital over a 6-month period were reviewed. A cost analysis using five variables was performed: operating theatre time, duration of hospital and high-care unit stay, pharmaceutical and blood products used, laboratory services used and diagnostic imaging studies performed. RESULTS: Twenty-three patients with serious abdominal gunshot injuries were admitted, of whom 21 (91%) were treated at the hospital from admission until discharge. Each admission cost approximately US dollars 1,467. Hospital stay (47%) and operating theatre (30%) costs accounted for most of the total cost. Pharmaceuticals and blood products (20%), laboratory services (2%) and imaging studies (1%) contributed less than 25% to the total cost. CONCLUSION: Serious abdominal gunshot injuries cost at least 13-fold more than the annual per capita South African government expenditure on health. This fiscal burden of approximately US dollars 2.9 million, almost 4% of the annual health budget, does not include the cost of treating other serious gunshot injuries. These findings highlight the need for successful violence prevention strategies in South African.


Subject(s)
Abdominal Injuries/economics , Abdominal Injuries/therapy , Emergency Service, Hospital/economics , Hospital Costs , Wounds, Gunshot/economics , Wounds, Gunshot/therapy , Abdominal Injuries/epidemiology , Abdominal Injuries/etiology , Cohort Studies , Combined Modality Therapy , Cost-Benefit Analysis , Developing Countries , Emergency Service, Hospital/statistics & numerical data , Female , Firearms/statistics & numerical data , Health Care Costs , Humans , Incidence , Injury Severity Score , Length of Stay/economics , Male , South Africa/epidemiology , Survival Rate , Wounds, Gunshot/diagnosis , Wounds, Gunshot/epidemiology
14.
Rev Sci Tech ; 23(2): 677-84, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15702727

ABSTRACT

This paper discusses food-borne zoonotic diseases by considering contemporary influences on food safety and examining pathogens at the human/animal interface. The authors also discuss the epidemiological surveillance of food-borne illnesses and the differences in disease statistics from one country to another. Before concluding with a number of recommendations, the paper highlights the importance of a collaborative approach to the prevention and control of food-borne diseases and discusses the need to co-ordinate the efforts of international agencies working in human health, animal health and food production. A regional case study is also included, in which the authors describe the food-borne disease situation in Latin America, as reported by surveillance systems in this region.


Subject(s)
Consumer Product Safety , Foodborne Diseases/epidemiology , Global Health , Animals , Food Chain , Humans , International Cooperation , Population Surveillance , Risk Assessment , Risk Management
18.
Arch Pediatr ; 9(3): 262-5, 2002 Mar.
Article in French | MEDLINE | ID: mdl-11938537

ABSTRACT

UNLABELLED: Chickenpox has a high risk of invasive group A streptococcal disease and necroziting fasciitis. CASE REPORT: A five-year-old girl, during chickenpox treated with ibuprofen, developed sepsis and edematous and necrotic lesions of the pelvis and the abdominal wall. The child improved with surgical treatment and adjunction of clindamycin to the antibiotic therapy. CONCLUSION: We review the optimal medical and surgical treatment of necrotizing fasciitis and discuss the role of chickenpox and non steroidal antiinflammatory agents in this disease.


Subject(s)
Chickenpox , Fasciitis, Necrotizing/microbiology , Streptococcal Infections , Streptococcus pyogenes , Chickenpox/therapy , Child, Preschool , Fasciitis, Necrotizing/therapy , Female , Humans , Streptococcal Infections/therapy
19.
Arch Pediatr ; 8(6): 577-83, 2001 Jun.
Article in French | MEDLINE | ID: mdl-11446177

ABSTRACT

UNLABELLED: Chronic recurrent multifocal osteitis (OCRM) is a rare condition in children, of unknown aetiology, which may be misdiagnosed as osteomyelitis, arthritis or tumour. PATIENTS AND METHODS: We present a retrospective multicentric study of 17 patients (five boys and 12 girls) with an average follow-up of 7.5 years (six months-25 years). RESULTS: A spectrum of presenting features is possible, ranging from bone lesions alone to lesions combined with arthritis, palmoplantar pustulosis or psoriasis. The diagnosis was delayed from two weeks to five years. Roentgenographic evaluation was often normal at the beginning of the disease or showed nonspecific bone reactions. Radioisotope bone scans assisted in establishing the diagnosis and in identifying lesions that were initially clinically silent. Bone biopsies were performed in seven cases. Histopathological examination showed only mild inflammatory nonspecific changes. Microbiological cultures were always negative. Treatments were different according to the evolution of the disease and the hospital. There was no response to antibiotics in seven patients. The response to nonsteroidal anti-inflammatory agents and steroids was moderate and often transient. Salazopyrine and pamidronate treatment used in two patients allowed a durable remission. We lost sight of four patients, pain persisted in three in spite of treatment, it disappeared in two with treatment, mild pain persisted in five without treatment and remission occurred in three without treatment. CONCLUSION: This study clarifies the clinical and radiologic features of chronic recurrent multifocal osteomyelitis. The recognition of this rare entity is often delayed and difficulties in patient management sometimes emerge from its usual protracted course.


Subject(s)
Osteomyelitis/pathology , Adolescent , Adult , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Biopsy , Bone and Bones/diagnostic imaging , Bone and Bones/pathology , Child , Child, Preschool , Chronic Disease , Diagnosis, Differential , Diphosphonates/therapeutic use , Drug Combinations , Female , Glucosamine/analogs & derivatives , Glucosamine/therapeutic use , Humans , Infant , Male , Osteomyelitis/diagnosis , Osteomyelitis/drug therapy , Pain/etiology , Pamidronate , Prognosis , Radionuclide Imaging , Recurrence , Sulfasalazine/therapeutic use
20.
Biometrics ; 57(2): 508-17, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11414577

ABSTRACT

Dependencies between two types of points in a spatial point process can be due either to a real dependence between the two types or to the dependence on common underlying variables. We propose a global test for dependence between two point processes that is valid for a wide range of models. In contrast with previously proposed methods, it is based on a number of local test statistics, which makes it possible to map the local association between the two processes. The behavior of the test is evaluated by a simulation study. It is then applied to a vegetation pattern data set from Burkina Faso.


Subject(s)
Plant Physiological Phenomena , Burkina Faso , Climate , Computer Simulation , Markov Chains , Models, Statistical , Multivariate Analysis , Poisson Distribution
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