Search

We present a combined experimental and theoretical study of the fragmentation of molecular CS2 after sulfur 1s Auger cascade decay, consisting of electron–multi-ion coincidence spectra of charged fragments and theoretical simulations combining density functional theory and molecular dynamics. On the experimental side, a procedure for a complete determination of all sets of ions formed is described. For many of the fragmentation channels, we observed a higher charge in one of the sulfur atoms than the other atoms. Based on these observations and the theoretical simulations where the time scale of the nuclear motion and decay is taken into account, we propose that KLL Auger decay after the 1s core hole creation, via 2p double hole states, results in highly charged and strongly repulsive states with one localized core hole. These localized core holes are sufficiently long-lived that some will decay after fragmentation of the molecular ion, thereby efficiently impeding charge exchange between the fragments.

Purpose. To estimate workforce participation characteristics and employees' attitudes regarding participation in workplace wellness programs. Design. Data from a statewide stratified random sample were used to compare small (Setting. A telephone survey of employed Iowans registered to vote. Subjects. Surveyed were 1171 employed Iowans registered to vote, ages 18 to 65. Measure. Among questionnaire survey modules were items from the Wellness Council of America Employee Needs and Interest Survey, the U.S. Census Bureau for employment documentation, and the World Health Organization Health and Work Performance Questionnaire for assessment of sickness absenteeism and presenteeism. Analysis. Prevalence of participation in screening and wellness programs was analyzed by employment size and levels of likeliness to participate, and multivariable analyses of employee baseline characteristics regarding participation in screening programs and likelihood of participation in wellness programs was presented as top and bottom quartiles. Results. Those employed in smaller workplaces participated less often in screening programs. Multivariable models identified male gender and those with an abnormal body mass index were associated with nonparticipation, while having a primary care physician was associated with participation. Very few items showed significant statistical difference in willingness to participate. Conclusion. Workforce characteristics and access to health care may influence participation in screening and wellness programs. Employment size is not a determining factor for willingness to participate in wellness programs.

To estimate quality-of-life (QoL), primary care, health insurance, prevention behaviors, absenteeism, and presenteeism in a statewide sample of the unemployed, self-employed, and organizationally employed.A statewide survey of 1602 Iowans included items from the Centers for Disease Control and Prevention QoL and Behavioral Risk Factor Surveillance System Survey prevention behavior questionnaires used to assess employee well-being; their indicator results are related to World Health Organization's Health and Work Performance Questionnaire-derived absenteeism and presenteeism scores.The unemployed exhibited poorer QoL and prevention behaviors; the self-employed exhibited many better QoL scores due largely to better prevention behaviors than those employed by organizations. Higher QoL measures and more prevention behaviors are associated with lower absenteeism and lower presenteeism.Employment status is related to measures of well-being, which are also associated with absenteeism and presenteeism.

Full investigation of deep defect states and impurities in wide-bandgap materials by employing commercial transient capacitance spectroscopy is a challenge, demanding very high temperatures. Therefore, a high-temperature deep-level transient spectroscopy (HT-DLTS) system was developed for measurements up to 1100 K. The upper limit of the temperature range allows for the study of deep defects and trap centers in the bandgap, deeper than previously reported by DLTS characterization in any material. Performance of the system was tested by carrying out measurements on the well-known intrinsic defects in n-type 4H-SiC in the temperature range 300-950 K. Experimental observations performed on 4H-SiC Schottky diodes were in good agreement with the literature. However, the DLTS measurements were restricted by the operation and quality of the electrodes.

We performed ab initio excited-state molecular dynamics simulations of a gas-phase photoexcited protonated Schiff base (C1-N2═C3-C4═C5-C6) to search for control mechanisms of its photoisomerization. The excited molecule twists by ∼90° around either the N2C3 bond or the C4C5 bond and relaxes to the ground electronic state through a conical intersection with either a trans or cis outcome. We show that a large initial distortion of several dihedral angles and a specific normal vibrational mode combining pyramidalization and double-bond twisting can lead to a preferential rotation of atoms around the C4C5 bond. We also show that selective pretwisting of several dihedral angles in the initial ground state thermal ensemble (by analogy to a protein pocket) can significantly increase the fraction of photoreactive (cis → trans) trajectories. We demonstrate that new ensembles with higher degrees of control over the photoisomerization reaction can be obtained by a computational directed evolution approach on the ensembles of molecules with the pretwisted geometries.

Purpose: We compared parents' perceived-as-appropriate ages with actual-performance ages for their children engaging in selected agricultural tasks or practices, and we examined the factors associated with age discrepancy. Methods: We analyzed data from the Keokuk County Rural Health Study collected among parents of children age 17 or younger. Parents were interviewed separately regarding the age of their children's involvement in 14 selected agricultural tasks and their opinions about appropriate age of involvement. Findings: Of the 264 families included, 86.5% with a son and 69.8% with a daughter reported having children involved in at least 1 of 14 selected agricultural tasks. The average actual-performance ages for children to be involved in any of the tasks were younger than those that parents perceived appropriate. Furthermore, in 6 of the 9 North American Guidelines for Children's Agricultural Tasks (NAGCAT) that we assessed, parents' perceived-as-appropriate ages were younger than minimum ages recommended by the NAGCAT. Driving an all-terrain vehicle (ATV) was the most common task with actual-performance age younger than the NAGCAT-recommended age; 53.0% of boys (n = 106) and 36.1% of girls (n = 61) did so under the recommended age. Boys and children who live on a farm, or whose parents have been or are farmers, were significantly more likely to perform agricultural tasks at earlier ages. Conclusions: Our results suggest farm parents and other rural stakeholders need to be better educated and encouraged to follow the NAGCAT guidelines, and that multilevel interventions need to be developed to ensure protection of children from agricultural injury and death. Language: en

Red blood cells (RBCs) can be removed from the bloodstream at an accelerated rate by antibody-mediated mechanisms in a number of immunologic conditions including the following: 1) autoimmune hemolytic anemias, 2) transfusion of incompatible allogeneic RBCs into a recipient whose blood contains a corresponding alloantibody, 3) transfusion of passive antibodies into a recipient whose RBCs express the cognate antigen, 4) transplacental transfer of maternal allogeneic RBC antibodies into a fetus with RBCs expressing the cognate antigen resulting in alloimmune hemolytic disease of the fetus and newborn, and 5) posttransplantation transfer of viable donor lymphocytes capable of producing antibodies directed against recipient RBCs (e.g., group O donor into group A recipient). When caring for patients with these disorders, having an accurate and safe method for determining in vivo RBC kinetics would be of considerable value for establishing the diagnosis, defining the pathophysiology, and assessing the response to therapy. The availability of RBC survival (RCS) methods that address safety issues (e.g., avoidance of radioactivity) is particularly important for vulnerable patient populations including fetuses, neonates, children, and pregnant women. Direct assessment of RCS requires the ability to distinguish cohort-labeled RBCs from the remaining RBCs in the circulation and to express their number as the relative proportion of labeled RBCs to total RBCs in that blood sample. The internationally recognized reference method for measuring RCS uses autologous or allogeneic RBCs labeled with chromium 51 (51Cr) and is based on concentration of 51Cr per unit volume of blood.1 Because transfusion of 51Cr-labeled RBCs exposes the recipient to radiation, this approach is viewed as unacceptable for research studies in the human fetus, neonate, and pregnant woman. Our laboratory and others2-4 have developed methods for measuring RCS in humans based on labeling of RBCs with biotin at one5-10 or more11 densities. Here the term density refers to biotin labels per RBC and is determined by our selection of the concentration of biotinylating reagent per milliliter of RBCs in the biotinylation reaction mixture. Biotin-labeled RBCs (BioRBCs) are quickly and easily enumerated by flow cytometry.11 The biotin RBC method has the following safety and technical advantages over the standard 51Cr method: 1) study subjects including vulnerable populations are not exposed to radiation; 2) small blood volumes (e.g., 20 μL) are required for monitoring; and 3) multiple, independent RCS measurements can be made simultaneously in the same individual by labeling RBCs at more than one biotin density. The aim of this study was to determine whether RBCs labeled with biotin at a single density can be used to accurately measure shortened RCS of RBCs experimentally coated (opsonized) with antibody simulating the situation present in immune-mediated hemolytic anemia. We hypothesized that short-term and long-term RCS measured using BioRBCs would agree with RCS determined using RBCs labeled with 51Cr.

Communications interconnects and networks will continue to play a large role in contributing to the global carbon footprint, especially in data center and cloud-computing applications exponential growth in capacity. Key to maximizing the benefits of photonics technology is highly functional, lower power, and large-scale photonics integration. In this paper, we report on the latest advances in the photonic integration technologies used for asynchronous optical packet switching using an example photonic integrated switched optical router, the label switched optical router architecture. We report measurements of the power consumed by the photonic circuits in performing their intended function, the electronics required to bias the photonics, processing electronics, and required cooling technology. Data is presented to show that there is room (potentially greater than 10 ×) for improvement in the router packet-forwarding plane. The purpose of this exercise is not to provide a comparison of all-optical versus electronic routers, rather to present a data point on actual measurements of the power contributions for various photonic integration technologies of an all-optical packet router that has been demonstrated and conclude, where the technology can move to reduce power consumption for high-capacity packet routing systems.

BACKGROUND: Anemia is a serious problem in critically ill neonates. To investigate the pathophysiology of anemia and responses to red blood cell (RBC) transfusions and erythropoietin therapy, repeated measurement of red blood cell volume (RCV) and blood volume is useful. To extend our previous sheep study in which RBCs were labeled at four different biotin densities, we assessed the validity of this multidensity method for in vivo measurement of circulating RCV in humans. STUDY DESIGN AND METHODS: In eight healthy adults, autologous RBCs were biotinylated at each of four biotin densities (6, 18, 54, and 162 µg biotinylation reagent/mL RBC), mixed, and infused intravenously; blood was sampled at 10, 20, and 60 minutes. At each time, RCV was calculated from dilution of individual RBC populations enumerated by flow cytometry. RCV measurements from the population of RBCs biotinylated at 6 µg/mL were chosen as the reference values because this density had been previously validated against the 51Cr method in vitro and in vivo in humans. RESULTS: Values for RCVs were not significantly different among the four densities of biotinylated RBCs at any of the three time points and did not change over 60 minutes. CONCLUSIONS: These studies provide evidence that four densities of biotinylated RBCs can be used in vivo for simultaneous, independent, accurate measurements of RCV in humans. We speculate that this method will also be useful for repeated measurement of RCV and blood volume in infants and other patient populations in whom radioactive labels should be avoided.

Synchronous optical packet buffering is presented as a solution for asynchronous time division multiplexed (TDM) optical packet switched networks. Truly asynchronous optical packet synchronization and buffering are demonstrated using multiple independent transmitters, synchronous optical buffers, and a burst mode receiver. Optical packet synchronizers are used to dynamically align incoming asynchronous packets to local timeslots for synchronous loading of buffers. Multiple optical buffers based on integrated InP technology resolve contention of packets destined for the same output port at the same time. TDM asynchronous optical packets are detected on a per packet basis using a burst mode receiver with better than 99.9% packet recovery. An analysis of power consumption of the synchronous buffers is presented and potential power reductions are discussed.

BACKGROUND: To investigate the pathophysiology of anemia and responses to red blood cell (RBC) transfusions and erythropoietin, repeated measurement of the circulating red blood cell volume (RCV) would be useful. Ovine erythropoiesis is similar to human erythropoiesis. Accordingly, a method for measuring RCV using either human or sheep RBCs labeled at different biotin densities has been previously validated in vitro. Here preclinical studies validating this method for in vivo measurement of circulating RCV in sheep are reported. STUDY DESIGN AND METHODS: For each sheep, autologous RBCs were biotinylated were at four discrete densities (12, 24, 48, and 96 µg biotinylation reagent/mL RBCs). The densities were mixed and infused intravenously. Blood was sampled five times over 1 hour beginning at 4 minutes. RCV values were determined based on dilution of each population of biotinylated RBCs and by the [14C]cyanate method. RESULTS: There was no difference among RCVs measured at all densities through 16 minutes; however, by 60 minutes, RBCs biotinylated at the highest density overestimated RCV by 7.6%. RCV values increased 41% over the hour, consistent with equilibration with a pool of RBCs sequestered in the spleen. RCV by the [14C]cyanate method paralleled results by the biotin method but averaged 8% greater. CONCLUSIONS: These studies provide evidence that all four densities of biotinylated RBCs can be used in sheep to simultaneously and independently determine RCV. We speculate that the multidensity biotinylation method will be useful both for multiple simultaneous measurements and for repeated measurement of circulating RCV and blood volume in humans.

This paper reports the characteristics and performance of a Time-of-Flight Mass Spectrometer (TOF-MS) for coincidence measurements between electrons and ions that has been developed jointly in Sweden and Brazil. The spectrometer, used for studies of inner-shell photoexcitation of molecules in the gas-phase, has been optimized by implementing ion and electron lenses to allow the use of relatively small diameter detectors. Simulations were performed to understand the lens performance and they show that ions (electrons) could be collected without angular discrimination with a maximum kinetic energy up to ten (two) times higher than without the lens actions. A rotary vacuum chamber allows the spectrometer axis to be positioned at different angles relative to the polarization vector of the excitation beam. An important characteristic of the apparatus is that the acquisition setup allows a multi-hit capability with 1 ns resolution. Hereby, Photoelectron-Photoion-Photoion Coincidence (PEPIPICO) measurements can be performed on molecules containing two or more atoms of equal mass. A method to obtain experimental detection efficiencies of a single ion and one of one, two or three electrons has been developed. A systematic study of the interaction region has been performed to determine the shape of the photon and gas beams. Measurements on molecular nitrogen demonstrate the spectrometer's ability to resolve fragments with the same charge to mass ratio arriving within only a few ns. Simulations and experimental results of fragmentation of two singly charged cation nitrogen atoms agree, confirming that the spectrometer performance is well understood. (C) 2010 Elsevier B.V. All rights reserved.

Studies have been made of the growth patterns of hands of elementary schoolchildren in Czechoslovakia (1707 children) and in the United States (1641 children). This paper compares the results of these studies and summarizes the patterns of growth for both hands of boys and girls aged from five to 12 years. The results indicate that the United States children generally have shorter and wider hands than their Czech counterparts. In both countries, boys have wider hands than girls, although there is evidence that at ages 11 and 12 years the girls' hands are longer. Growth spurts in both width and length measurements are apparent in children's hands in both countries, but the spurt often occurs at an earlier age in Czech children. Awareness of these general patterns of hand growth should be of assistance to the hand surgeon.

With the consensus among the scientific community in the late 1960’s that the use of radioactive materials was ethically untenable in research studies of fetuses, neonates, and pregnant women, the rate of progress in understanding red blood cell (RBC) kinetics and RBC volume in the perinatal period has nearly come to a halt (1). Yet, the need for understanding has continued to accelerate. Advances in obstetrics and in fetal medicine now permit intrauterine fetal blood sampling, transfusion, and other therapies to be delivered directly into the fetal circulatory system. Advances in neonatal medicine during this period include neonatal therapies that have resulted in improved survival and outcomes of extremely low birth weight (

The Keokuk County Rural Health Study is a population-based study of an agricultural community in Iowa. The study includes in-depth evaluations of respiratory disease, injury, and other health outcomes in relation to environmental and occupational exposures. This article reports descriptive findings on pesticide use from among the 1191 participants completing occupational surveys. Fifty-one percent (612) of respondents (farmers and non-farmers) had applied insecticides including lawn and garden chemicals at home during the past year. Thirty-three percent (395) of respondents had personally mixed or applied farm chemicals during their life. One-hundred and four had a current pesticide applicator's license. Information on the specific types of pesticides and protective measures used was obtained for the 144 individuals who had mixed or applied pesticides on farms within the previous year. Of these individuals, 67% worked with fertilizers, 49% used herbicides, 48% used crop insecticides, 28% used crop storage insecticides, 45% applied livestock insecticides, and 9% worked with fungicides. The use of personal protective equipment such as gloves, aprons, and respirators varied depending on the chemical. A substantial proportion did not use gloves even for mixing. Thirty-five percent reported at least one suspected work-related symptom after working with pesticides during the previous year. The lack of differences in protective equipment use between applicators who have completed pesticide applicator training courses and those who have not suggests a need to develop more effective training methods. The increased use of protective equipment when applying odorous agrochemicals suggests that addition of an odorant to more toxic pesticides may be a successful intervention strategy.

Extremely intense and ultrafast X-ray pulses from free-electron lasers offer unique opportunities to study fundamental aspects of complex transient phenomena in materials. Ultrafast time-resolved methods usually require highly synchronized pulses to initiate a transition and then probe it after a precisely defined time delay. In the X-ray regime, these methods are challenging because they require complex optical systems and diagnostics. Here we propose and apply a simple holographic measurement scheme, inspired by Newton's 'dusty mirror' experiment, to monitor the X-ray-induced explosion of microscopic objects. The sample is placed near an X-ray mirror; after the pulse traverses the sample, triggering the reaction, it is reflected back onto the sample by the mirror to probe this reaction. The delay is encoded in the resulting diffraction pattern to an accuracy of one femtosecond, and the structural change is holographically recorded with high resolution. We apply the technique to monitor the dynamics of polystyrene spheres in intense free-electron-laser pulses, and observe an explosion occurring well after the initial pulse. Our results support the notion that X-ray flash imaging can be used to achieve high resolution, beyond radiation damage limits for biological samples. With upcoming ultrafast X-ray sources we will be able to explore the three-dimensional dynamics of materials at the timescale of atomic motion.

The optoelectronic properties of Bi-doped hydrogenated amorphous germanium (a-Ge:H), with relative impurity concentrations [Nimp/NGe] ranging between 8 × 10− 6 and 5.5 × 10− 3, are reported. The incorporation of Bi produces small changes in the dark conductivity of a-Ge:H. For a three orders of magnitude change in impurity concentration the room-temperature conductivity changes by just one order of magnitude. Within this doping range no, or small, changes were measured in the values of the pseudo-gap, the Urbach energy, and the hydrogen content. The Fermi level always remains far from the conduction band edge, shifting by only 0.1 eV for the sample with the largest doping concentration. The main conclusion is that Bi is a very inefficient active donor in a-Ge:H. The likely reasons for such behavior are discussed. Fil: Burmeister, F. Uppsala University; Suecia. Universidade Estadual de Campinas; Brasil Fil: Comedi, David Mario. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Física del Sólido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina Fil: Chambouleyron, I.. Universidade Estadual de Campinas; Brasil

Although agriculture is one of the most hazardous industries, the costs of agricultural injuries and illnesses are not well known. This study aimed to determine the cost burden from compensated injuries and occupational diseases in Finnish agriculture using workers compensation records. The incidence rates in 1996 were 7.4/100 for injuries and 0.61/100 for occupational diseases. Men had a higher risk of injury (RR = 1.89; 95% CI: 1.81-1.97), but a lower risk of an occupational disease (RR = 0.68; 95% CI: 0.60-0.78), compared to women. The total cost burden was 75 (Euros) per person in 1983, increasing to 215 in 1999. The total insurance cost in 1996 was 23.5 million consisting of medical care (16%), per diem (lost time compensation within one year from the incident) (37%), pension (lost time compensation after one year from the incident) (23%), survivors pension (3%), impairment allowance (7%), rehabilitation (6%), and other costs (9%). The total cost was 0.7% of the national gross farm income and 2.2% of the net farm income. The mean cost of 1996 cases was 1340 for injuries and 6636 for occupational diseases. Injuries represented 92% of the claims and 71% of the total costs. Occupational diseases represented 8% of the claims and 29% of the costs. Twenty percent of the most severe claims represented 79.5% of the total insurance costs. Injuries and occupational diseases result in significant costs in agriculture. Lost time was the largest cost item. Overall, injuries were more costly than occupational diseases. This study indicates that the 20%-80% rule applies to agricultural injury and illness costs, and from the cost standpoint, it is important to focus prevention efforts on the most severe incidents.

Objective: This study estimates the prevalence of male abusive behavior reported by men and their female partners and identifies characteristics of abusive men. Design: Baseline survey from a population based cohort study of general health. Setting: A rural county in Iowa, USA. Subjects: 572 men and their cohabitating female partners. Main outcome measures: Male-to-female physical, emotional, and sexual abuse reported by either partner. Results: In this cohort, 13.6% of men had performed at least one act of physical abuse and 34.9% emotional abuse. More than 45% of abusive men reported their own behaviors. Alcohol problems, antisocial personality characteristics, depressive symptoms, and financial stress were all positively associated with both physical and emotional abuse, but suicidal thoughts were less likely among abusers. Conclusion: Identification of common characteristics of abusive men may predict proclivity towards partner violence and barriers to behavior modification.

Background The objective of this study was to measure changes in injury claim rates after a premium discount program was implemented in the Finnish farmers' workers' compensation insurance. We focused on measures that could indicate whether the changes occurred in the true underlying injury rate, or only in claims reporting. Methods Monthly injury claim rates were constructed at seven disability duration levels from January 1990 to December 2003. We conducted interrupted time series analyses to measure changes in the injury claim rates after the premium discount was implemented on July 1, 1997. Three additional policy change indicators were included in the analyses. Results The overall injury claim rate decreased 10.2%. Decreases occurred at four severity levels (measured by compensated disability days): 0 days (16.3%), 1–6 days (14.1%), 7–13 days (19.5%), and 14–29 days (8.4%). No changes were observed at higher severity levels. Minor injuries had a seasonal pattern with higher rates in summer months while severe injuries did not have a seasonal pattern. Conclusions The premium discount decreased the overall claim rate. Decreases were observed in all categories up to 29 disability days. This pattern suggests that under-reporting contributes to the decrease but may not be the only factor. The value of the premium discount is lower than the value of a lost-time claim, so there was no financial reason to under-report lost-time injuries. Under-reporting would be expected to be greatest in the 0 day category, but that was not the case. These observations suggest that in addition to under-reporting, the premium discount may also have some preventive effect. Am. J. Ind. Med. 48:100–109, 2005. © 2005 Wiley-Liss, Inc.

Epidemiologic studies of farm children are of international interest because farm children are less often atopic, have less allergic disease, and often have less asthma than do nonfarm children--findings consistent with the hygiene hypothesis. We studied a cohort of rural Iowa children to determine the association between farm and other environmental risk factors with four asthma outcomes: doctor-diagnosed asthma, doctor-diagnosed asthma/medication for wheeze, current wheeze, and cough with exercise. Doctor-diagnosed asthma prevalence was 12%, but at least one of these four health outcomes was found in more than a third of the cohort. Multivariable models of the four health outcomes found independent associations between male sex (three asthma outcomes), age (three asthma outcomes), a personal history of allergies (four asthma outcomes), family history of allergic disease (two asthma outcomes), premature birth (one asthma outcome), early respiratory infection (three asthma outcomes), high-risk birth (two asthma outcomes), and farm exposure to raising swine and adding antibiotics to feed (two asthma outcomes). The high prevalence of rural childhood asthma and asthma symptoms underscores the need for asthma screening programs and improved asthma diagnosis and treatment. The high prevalence of asthma health outcomes among farm children living on farms that raise swine (44.1%, p = 0.01) and raise swine and add antibiotics to feed (55.8%, p = 0.013), despite lower rates of atopy and personal histories of allergy, suggests the need for awareness and prevention measures and more population-based studies to further assess environmental and genetic determinants of asthma among farm children.

To investigate whether the association between agricultural pesticide use and the risk of non-Hodgkin's lymphoma (NHL) is modified by a family history of hematopoietic cancer, including leukemia, myeloma, and lymphoma, we analyzed pooled data on white men from three population-based, case-control studies of NHL conducted in Iowa/Minnesota, Kansas, and Nebraska. Information on the agricultural use of insecticides, fungicides, and herbicides; a family history of cancer; and other risk factors was obtained by interviewing 973 cases and 2,853 controls or, if deceased, their next-of-kin (37% of cases, 43% of controls). The NHL risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age, state of residence, type of respondent, and use of hair dye. Compared to men with no family history of cancer, the ORs (95% CIs) of NHL was 1.5 (1.3–1.8) for men with a family history of nonhematopoietic cancer, and 2.7 (1.9–3.7) for those with a history of hematopoietic cancer among first-degree relatives. This positive association was noted for each group of NHL defined according to the Working Formulation, and was most pronounced for small lymphocytic NHL. Among direct respondents, farmers who used pesticides and had a positive family history of cancer or hematopoietic cancer were not at elevated risk of NHL, compared to nonfarmers who had no family cancer history. However, among proxy respondents, ORs were elevated for farmers who had a positive family history of hematopoietic cancer and used animal insecticides (OR = 4.6; 1.9–11.2), crop insecticides (OR = 4.7; 1.6–13.4), or herbicides (OR = 4.9; 1.7–14.2), although the interaction of family history of cancer and agricultural pesticide use was not statistically significant. In summary, the joint effects of the family cancer history and pesticide use were limited to proxy respondents with wide CIs and, thus, provide little evidence that a family history of cancer modifies the association of agricultural exposures with NHL.

An in-depth photoionization study of the inner-valence electrons in HCl and DCl has been performed using synchrotron radiation. A series of photoelectron spectra of HCl were obtained at a resolution of 23 meV over the binding energy range 25-30.5 eV at various excitation energies and at two different electron collection angles relative to the plane of polarization of the undulator radiation. In addition, photoelectron spectra of DCl were recorded at two different excitation energies. These spectra were compared directly with the threshold photoelectron spectra of HCl and DCl that were recorded previously under similar resolution conditions (similar to30 meV). This comparative study reveals new information on the nature of the numerous band systems observed in this binding energy region. In addition, we present the experimental confirmation of the theoretical prediction given by Andersson et al (2001 Phys. Rev. A 65 012705) that a vibrational progression showing interference structure would appear in the main inner-valence ionization band in the photoelectron spectrum of DCl at a resolution of 10 meV.

BACKGROUND: The extend potential applications of a nonradioactive method for measuring circulating RBC volume, we tested the hypothesis that RBC volume could be determined independently using two populations of RBCs labeled with low-density biotin (LDB1) and high-density biotin (HDB). STUDY DESIGN AND METHODS: In 10 healthy adults, autologous RBCs were labeled with HDB, LDB, or 51Cr. The labeled RBCs were mixed and transfused. RBC volume was measured in postinfusion peripheral venous blood by quantitating dilution of each population of labeled RBCs. RESULTS: RBC volume measured using either LDB or HDB cells agreed well with RBC volume measured using 51Cr. For the regression of RBC volume by LDB versus RBC volume by 51Cr, correlation = 0.994 and slope = 0.933. For HDB versus 51Cr, correlation = 0.982 and slope = 0.953. RBC volume measured a second time in four subjects with HDB agreed well; mean CV for the differences between HDB and 51Cr were less than 5 percent. CONCLUSIONS: Using RBCs labeled with two different densities of biotin, RBC volume can be accurately measured simultaneously and repeatedly in the same subject without radiation exposure.

The aim of this project was evaluate the effectiveness of an oil sprinkling system as a dust -reduction method for swine production facilities. This article presents the results of the second-year experiment of a multi -year study. The first -year experiment demonstrated that a 5% oil -water emulsion automatically applied at the rate of 3 and 5 g/pig/day achieved a 23% to 34% reduction in total dust. The modifications for the second year experiment included: (1) increasing oil application rate to 7 and 8 g/pig/day, (2) replacing sprinkler heads to achieve a smaller droplet size and a more direct spray pattern on pen- floor surfaces, and (3) more closely matching the treatment and control rooms by stage in the pig production cycle. Four swine finishing rooms were used for this study; two were treatment rooms (soybean oil at 7 g/pig/day, and canola oil 8 g/pig/day) and two were control rooms. The treatment rooms had a low-pressure oil -sprinkling system, which sprinkled 5% oil - to-water mixture 12 times per day, 12 s each time. Concentrations of several environmental contaminants were measured. The average total dust concentration in the control rooms was 1.39 mg/m3. The average total dust concentration in the treatment rooms was 0.65 mg/m3. The treatment reduced dust by an average of 52%, (p = 0.0001). There was no difference in the degree of dust control between soybean oil and canola oil. The respirable dust concentrations were very low in all rooms, and there were no significant differences between rooms in ammonia, carbon dioxide, temperature, or humidity.

Background There are conflicting findings about the prevalence of asthma among farm and nonfarm children. Objectives We sought to estimate asthma prevalence and morbidity and determine differences between farm and nonfarm children. Methods The study population consisted of all children aged 6 to 14 years enrolled in 10 school districts in 2 noncontiguous rural Iowa counties from 2000 through 2002. The mailed parental screening questionnaire included the International Study of Asthma and Allergies in Childhood core questionnaire, items from the Functional Severity Index, and items on physician diagnosis and medication and urgent care use. Results The response rate was 86.6%. The 12-month prevalence of wheeze was 19.1%. Self-reported physician diagnosis of asthma was reported by 13.4%. On multivariable analysis controlling for age, sex, and county, children who lived on farms were less likely than those who lived in town to have ever wheezed (odds ratio, 0.71; 95% CI, 0.58-0.87) or to have wheezed during the past year (odds ratio, 0.77; 95% CI, 0.60-0.98). However, this protective association with farming was only observed in one of the study counties. Among those who wheezed, farm and nonfarm children were equally likely to have been given a diagnosis of asthma and had comparable morbidity. Conclusion By using a standardized questionnaire with a high response rate in this large, rural, population-based study, asthma prevalence rivaled that in large Midwestern cities. Unmeasured risk factors might account for the apparent protective effect in Keokuk County. These findings cast doubt on a protective effect of rural life for the development of childhood asthma.

We present multicoincidence spectra of nitrogen, formic acid and methyl methacrylate. We demonstrate how to probe the local symmetry of molecular orbitals from molecules core excited with linearly polarized synchrotron radiation. The intensity distribution of the photoelectron photo-ion photo-ion coincidence (PEPIPICO) spectrum reflects the selectivity and localization of core excitation by polarized light. By simulating the spectra the angular dependence of the fragmentation is determined.

CONTEXT: Although farmers are at risk for injuries from contact with large livestock, few previous studies have examined risk factors for animal-related injuries. PURPOSE: This case-control study, nested in the Agricultural Health Study, aimed to assess risk factors for animal-related injury among Iowa large-livestock farmers. METHODS: A screener questionnaire sent to 6999 farmers identified 116 farmers with large livestock who had an animal-related injury requiring medical advice/treatment in the previous year. Several possible risk factors for injury were assessed by comparing these farmers with 342 farmers who had livestock but were not injured in the previous year. FINDINGS: A multiple logistic regression analysis showed significant associations between animal-related injury and the use of a hearing aid (odds ratio [OR] = 5.4 [95% CI, 1.6 to 18.0]), doctor-diagnosed arthritis or rheumatism (OR = 3.0 [95% CI, 1.7 to 5.2]), education beyond high school (OR = 1.8 [95% CI, 1.1 to 2.8]), and a younger age. Farmers engaged in off-farm work were less likely to sustain animal-related injuries (OR = 0.4 [95% CI, 0.2 to 0.8]). CONCLUSIONS: This is the first study to show associations between animal-related injury and a younger age, hearing difficulties, and doctor-diagnosed arthritis. Hearing loss and arthritis, which are more common among farmers than among other workers, may be particularly important risk factors to address in future preventive studies.

A four-element conical electron lens has been developed in view of its integration to a double toroidal electron energy analyzer (DTA) dedicated to Auger electron–ion coincidence measurements. The lens design, using electron trajectory numerical simulations, was entirely guided by the perspective of analyzing energetic electrons with high resolution in the multicoincidence regime. The design, construction, and experimental characterization stages of this electron optics system are described in this article. Emphasis is put on the importance of third generation synchrotron radiation sources when performing such multicoincidence experiments.

PURPOSE: To investigate the association between alcohol consumption and the risk of non-Hodgkin's lymphoma (NHL) and to examine whether the association is modified by a family history of hematolymphoproliferative cancer (HLPC). METHODS: Data on white men from two population-based case-control studies of NHL conducted in Iowa/Minnesota and Kansas were pooled for this analysis. Information on alcohol consumption, family history of HLPC, and other factors was obtained by interviewing 792 cases and 2193 controls or, if deceased, their next-of-kin. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: There was no clear association between NHL and the use of alcohol, beer, hard liquor, or wine. The relationship, however, may differ according to a family history of HLPC. Alcohol use was not associated with the risk of NHL in men without a family history of HLPC (ORs = 0.8 and 0.9 for men consuming alcohol ⩽ median and > median, respectively), the presence of a family history in the absence of alcohol use was associated with a slightly increased risk (OR = 1.4; 95% CI 0.8–2.5), whereas risks of NHL among men with a positive family history were 2.1 (CI 1.0–4.7) for men consuming alcohol ⩽ median (13.7 g/day) and 2.8 (1.3–5.9) for men consuming alcohol greater than median. CONCLUSIONS: The present data found no clear association between alcohol consumption and the risk of NHL among men without a family history of HLPC, whereas alcohol intake was associated an elevated risk in men with a positive family history. The finding of effect modification of the alcohol-NHL association by a family history of HLPC is novel and requires confirmation.

The Auger–Doppler effect in the experimental spectra of HF and DF is presented, and the dynamics of ultra-fast dissociation in the core-excited state are discussed. The Doppler splitting of the atomic Auger peak is calculated and simulated using a classical model and a very good agreement is found between experiment and simulation. It is shown that the difference in photon energy relative to the resonance is transferred completely into the kinetic energy release (KER). This is expected to be a general phenomenon, but is clearly illuminated in the HF/DF case. Thus the fragment velocity can be controlled through photon energy detuning.

Background: The purpose of this study was to describe the frequency, characteristics, and risk factors of unintentional adult injury in a rural population. Methods: We interviewed 1,644 adults representing an all-rural county in Iowa. Analyses used bivariate and multivariable logistic regression. Results: Participants' mean age was 53 years, and 54% were women. Twenty-three percent (n = 380) of participants reported an injury during the past 12 months, of which four fifths were treated. Overexertion (25%) and falls (22%) caused nearly half the injuries. Women with high levels of depression symptoms had 1.57 times (95% confidence interval, 1.05-2.33) the prevalence of injury occurrence as did women with low levels of depression symptoms. Men with a CAGE score of 2 or more had between 0.98 and 2.56 times (according to the range of values of the relevant odds ratio 95% confidence interval) the prevalence of injury episode of men without this exposure. Conclusion: The association of injury occurrence with alcohol problems is consistent with prior research, but the increased prevalence of injury associated with high levels of symptoms of depression requires further study and explanation.

Objectives—In the United States, firearm deaths are almost as frequent as motor vehicle deaths. Firearm unintentional and suicide death rates are raised in rural areas. This study examines firearm prevalence and storage practices in three different types of rural households. Methods—Adults from a stratified random sample of 983 households in a rural Iowa county were interviewed. The χ2 test of independence was used to assess association between loaded, unlocked firearms and seven behavioral and demographic risk factors. Results—Nearly 67% of respondents reported firearms in their households. Nearly 7% of households had a loaded, unlocked gun. Prevalence of firearms at home was higher while prevalence of loaded, unlocked guns was lower than reported in other surveys. Prevalence of loaded, unlocked guns in farm households, 10.5%, was about twice the level in town households, 5.5% (χ2 test, p=0.033). Having taken a gun safety course was associated with more than double the prevalence of a loaded, unlocked gun, 13.5% v 5.1% (χ2 test, p=0.001). The prevalence of loaded, unlocked guns in households with a handgun, 19.3%, was four and one half times higher than in households with a long gun only, 4.2% (χ2 test, p=0.001). Households with someone with a lifetime prevalence of alcohol abuse or dependence were about twice as likely as other households, 13.0% v 6.6% (χ2 test, p=0.004), to report having loaded, unlocked firearms. Conclusions—Anyone interested in promoting safe storage of firearms in rural homes should consider these observations.

Agriculture is one of the most hazardous occupations in the United States. We examined the work-related injury rate and risk factors among 290 Iowa male principal farm operators using a population-based, prospective study. Baseline data were collected between 1991 and 1994, and injury events were surveyed in the fall of 1995. Cumulative incidence of farmwork-related injury during the previous year was 10.5%. We found that depressive symptoms (odds ratio, 3.22; 95% confidence interval, 1.04 to 9.99) and the number of hours working with animals (odds ratio, 2.14; 95% confidence interval, 1.04 to 4.44) were associated with the incidence of farmwork-related injuries.

The sulfur L-shell photoelectron spectrum of the carbon disulfide molecule has been studied using monochromated synchrotron radiation with a photon energy of 250 eV. The spectrum is atomic like, showing three major bands that can be associated with the sulfur (2p-1)2P3/2,12 and (2s-1)2S1/2 ionic states. A closer inspection shows that the 2P3/2 state is further split into two components separated by 128 meV due to the molecular field. The resulting ionic states are located at 169.806 eV (0-0 energy), 169.934 eV (0-0 energy), 171.075 eV (0-0 energy) and 237.05±0.2 eV (centroid), respectively. Vibrational progressions in the (2p-1) bands are attributed to the asymmetric ν3 mode, which gives evidence of a localization of the core hole. The following values were obtained for the vibrational constants: ωe = 196.7±1.1 meV; ωexe = 0.2±0.5 meV. A curve fit of the vibrational lines using a Voigt function gave a natural width of 59.6±1.8 meV for the (2p-1) states, corresponding to a lifetime of 11 fs, and a spectrometer broadening of 38.2±1.8 meV. The (2p-1) bands are accompanied by shake-up structures occurring at 6-18 eV higher energies. They are interpreted mainly in terms of excitations to the unoccupied 3πu* orbital in the final ionic state. The (2s-1)2S1/2 band is broad and structureless due to fast Coster-Kronig processes. A fitting of a Voigt function gives a natural line-width of 1.85 eV which corresponds to a lifetime of 0.4 fs.

Background: Unintentional injuries represent a major cause of morbidity and mortality in rural communities. This study aimed to determine the distribution of injury risk factors in a rural Iowa community and to identify the rural subgroups at highest risk for injury. Methods: We reported on 1583 participants, aged ≥25 years, from Round One of the Keokuk County Rural Health Study, a longitudinal panel study of a rural community. The self-reported data were collected during face-to-face interviews. Results: Our data suggested that several risk factors for injury are not uniformly distributed among rural populations. Male farmers were significantly less likely to wear their seatbelts than townspeople or rural nonfarmers. However, farm women were as likely to wear seatbelts as other women. Both male and female farmers were more likely to use all-terrain vehicles than townspeople or rural nonfarmers. In contrast, townspeople were more likely to ride bicycles than either farmers or rural nonfarmers. Townspeople were less likely to have firearms in their homes than either farmers or rural nonfarmers. Farmers were most likely to have fired a gun in the last year. Male farmers aged Conclusions: These differences in risk behavior in a rural county suggest the possibility of targeting specific rural injury prevention interventions at those with the highest risk for dangerous behavior.

BACKGROUND. The underrepresentation of African-Americans among medical research participants is receiving considerable attention because of recent government mandates for the inclusion of all racial/ethnic groups in human subject research. Therefore, there is a need to determine factors that influence minority enrollment in medical research studies. METHODS. Between 1998-1999, 91 African-American residents of the Detroit Primary Metropolitan Statistical Area participated in a mail and telephone survey designed to examine impediments to participation in medical research studies. Chi-square tests and multiple logistic regression analyses were used to examine the association between race, issues related to trust in medical researchers, and the willingness to participate in medical research studies. RESULTS. African-American respondents were somewhat less willing to participate if they attributed high importance to the race of the physician when seeking routine medical care, believed that minorities or the poor bear most of the risks of medical research, and, most especially, their knowledge of the Tuskegee Study resulted in less trust in medical researchers. CONCLUSIONS. These data reiterate the need for medical researchers to build trusting relations with African-Americans and to conduct research in an ethical manner. This includes maximizing benefits, reducing risks, and assuring distributive justice to all medical research study participants.

Objective: Data from three population-based case–control studies conducted in Kansas, Nebraska, Iowa, and Minnesota were pooled to evaluate the relationship between the use of organophosphate pesticides and non-Hodgkin's lymphoma (NHL) among white male farmers.

Background Farmers have been previously reported to have higher rates of depression and suicide compared to other occupations. Comparisons of depressive symptoms and risk factors for states should increase understanding of depression in farmers. Methods Representative samples of 385 Iowa and 470 Colorado male principal farm operators in the respective state Farm Family Health and Hazard Surveillance projects were evaluated for depressive symptoms by using the CES-D scale. Risk factors were determined by using weighted multiple logistic regression analyses. Results Iowa farmers were 1.74 times (P

BACKGROUND: Most very low birth weight (

Most extremely low birth weight (1 kg) infants receive red blood cell (RBC) transfusions. RBCs stored up to 42 days can be transfused safely in small volumes to preterm infants; however, because the formulation of RBC anticoagulant/preservative solutions differs, clinical studies are required to document the safety of each solution before widespread use. Our goal was to study the feasibility and safety of AS-3 anticoagulant/preservative solution to preterm infants.Two clinical studies were conducted in sequence: (1) a randomized trial to compare RBC transfusions given as stored (or =42 days) AS-3 RBCs (11 infants) versus fresh (or = 7 days) citrate, phosphate, dextrose, and adenine RBCs (10 infants) and (2) a subsequent evaluation of the safety of stored AS-3 RBCs in 33 additional preterm infants given 120 AS-3 RBC transfusions.Results of both the randomized study and the subsequent evaluation documented that AS-3 RBCs storedor =42 days and transfused in small volumes (15 mL/kg) were safe for RBC transfusions of preterm infants. Donor exposure was significantly reduced, clinical transfusion reactions were rare, and post-transfusion blood hematocrit, pH, and plasma Na, K, Ca, lactate, and glucose measurements were similar when AS-3 and citrate, phosphate, dextrose, and adenine RBC transfusions were compared.AS-3 RBCs can be used safely for small-volume RBC transfusions for preterm infants.

This research project was conducted in collaboration with the Iowa Department of Public Health to evaluate whether property owners who follow recommended procedures for lead-based paint removal/repair can do the work safely and effectively. This study included 29 homes where a lead-based paint hazard had been identified and lead-based paint was removed or repaired (hazard reduction). Exposure evaluation included pre-project surface dust wipe sampling, air monitoring during lead-based paint removal, post-project surface dust wipe sampling, and pre- and post-project blood samples from adult study participants. The comparison of surface dust wipe samples taken before and after lead paint hazard reduction was used to evaluate the effectiveness of lead paint hazard reduction. The lead loadings on window sill surfaces in the work area were significantly lower after completion of the project (p = 0.04), and the lead-based paint removal did not contaminate the adjoining living area. The proportion of homes with surface dust lead loading exceeding Department of Housing and Urban Development (HUD) clearance standard was 73 percent pre-project and 38 percent post-project. Personal airborne exposures during lead removal activities (geometric mean = 59.3 micrograms/m3) reinforce the need for respiratory protection and good hygiene. There was no difference in adult pre-/post-blood levels, indicating that participants did remove lead in a safe manner with respect to their own exposures. The results indicate that hazard reduction can be done effectively when recommended procedures for the removal of lead-based paint are followed.