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Results for “FAIR data”

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PubMed2002

The Safety and Efficacy of Anabolic Steroid Precursors: What is the Scientific Evidence?

OBJECTIVE: Anabolic steroid precursors have gained widespread popularity as ergogenic supplements. Advertisements for these supplements claim that they increase endogenous testosterone production and protein synthesis, resulting in increased lean body mass and strength during training. At this time scientific support is limited, but the potential for serious side effects exists and the popularity of these supplements continues to grow. This review provides rationales for the ergogenic claims regarding steroid precursors and compares claims with data from scientifically controlled investigations. DATA SOURCES: A search of MEDLINE and SPORT Discus from 1960 to 2001 using the key words dehydroepiandrosterone, androstenedione, and androstenediol in combination with testosterone, estrogen, exercise, performance, and side effects. DATA SYNTHESIS: Although fairly new to the athletic community, steroid precursors have been used as ergogenic or anabolic agents for quite some time. Suggested gains in strength and lean body mass are attributed to an increase in the endogenous production of testosterone and enhanced protein synthesis. Most of the scientific data, however, do not support manufacturers' ergogenic claims, and the potential for serious side effects, such as decreased high-density lipoprotein cholesterol and increased estrogen concentrations, has been associated with precursor use. Thus, the safety and efficacy of these supplements must be questioned. CONCLUSIONS/RECOMMENDATIONS: It appears that the risks associated with the use of anabolic steroid precursors outweigh any possible ergogenic benefits. Furthermore, these supplements are banned by most athletic organizations. Thus, it is extremely important that athletic trainers are able to educate athletes on these issues so they can continue to perform at an optimum level in a safe and healthy manner.

Journal Article↗

PubMed2000

Specific heat of helium confined to a 57- &mgr;m planar geometry near the lambda point

We report measurements of the specific heat of liquid helium confined to 57-&mgr;m planar gaps extending to within a few nanokelvin of the bulk lambda transition. The data are in fair agreement with Monte Carlo estimates for finite-size effects and with renormalization-group-theory predictions above the transition. Far from the transition, we find surface specific heat exponents, alpha(s) = 0.64+/-0.05 below, and 0.65+/-0.2 above, which compare well with the prediction of 0.658. Comparison with other recent data on small length scales shows some areas of agreement.

Journal Article↗

PubMed1976

Estimation of assortative mating preferences in the Arctic skua.

Methods are described for the maximum likelihood estimation of mating preferences in models of assortative mating for monogamous and polygamous organisms. These methods are applied to data of matings of the three phenotypes, pale, intermediated and dark of the Arctic Skua. The data were obtained by exhaustive surveys of the Arctic Skua populations on the islands of Fair Isle and Foula. The data give evidence of significant assortative mating of pale birds on Foula and intermediate birds on Fair Isle. The combined data show that there is very highly significant assortative mating, but only of intermediates. In previous surveys, data, in which intermediates and darks were not distinguished, were obtained from a number of islands in the Shetlands. These data, combined with the present data, show that the overall assortative mating of pale is very highly significant with no evidience of heterogeneity. The assortative mating of intermediate birds on Fair Isle agrees with other evidence showing that inermediate males have an advantage as a result of sexual selection.

Animals↗

PubMed2005

Phylogenetic profiling of protein interaction networks in eukaryotic transcription factors reveals focal proteins being ancestral to hubs.

The combination of genomic, proteomic and other data, enables to reconstruct the evolution of complex cellular units thus transcending the more reductionistic view of traditional molecular phylogeny. However, most models which try to investigate the evolution of protein interaction networks so far are based on the analysis of their global statistical properties, such as their scale-free behaviour. We have investigated phylogenies of three families of ancient eukaryotic transcription factors for which fairly reliable interaction data are available. For all three families, bZIP, bHLH and NR (nuclear receptors), we find that homo-dimerising proteins were probably the ancestors and that series of single gene duplications, in combination with domain-rearrangements, were the main driving force in establishing the basic network architecture. However, the overall scaling behaviour does not always precisely confer to some theoretical models on network evolution. In conclusion, new models which reflect the biological details of molecular evolution, need to be developed.

Basic-Leucine Zipper Transcription Factors↗

PubMed2001

Two-compartment exchange model for perfusion quantification using arterial spin tagging.

The original well-mixed tissue model for the arterial spin tagging techniques is extended to a two-compartment model of restricted water exchange between microvascular (blood) and extravascular (tissue) space in the parenchyma. The microvascular compartment consists of arterioles, capillaries, and venules, with the blood/tissue water exchange taking place in the capillaries. It is shown that, in the case of limited water exchange, the individual FAIR (Flow-sensitive Alternating Inversion Recovery) signal intensities of the two compartments are comparable in magnitude, but are not overlapped in time. It is shown that when the limited water exchange is assumed to be fast, flows quantified from the signal-intensity difference are underestimated, an effect that becomes more significant for larger flows and higher magnetic field strengths. Experimental results on cat brain at 4.7 T comparing flow data from the FAIR signal-intensity difference with those from microspheres over a cerebral blood flow range from 15 to 150 mL 100 g(-1) min(-1) confirm these theoretic predictions. FAIR flow values with correction for restricted exchange, however, correlate well with the radioactive microsphere flow values. The limitations of the approach in terms of choice of the intercompartmental exchange rates are discussed.

Animals↗

PubMed2006

Cell cycle-specified fluctuation of nucleosome occupancy at gene promoters.

The packaging of DNA into nucleosomes influences the accessibility of underlying regulatory information. Nucleosome occupancy and positioning are best characterized in the budding yeast Saccharomyces cerevisiae, albeit in asynchronous cell populations or on individual promoters such as PHO5 and GAL1-10. Using FAIRE (formaldehyde-assisted isolation of regulatory elements) and whole-genome microarrays, we examined changes in nucleosome occupancy throughout the mitotic cell cycle in synchronized populations of S. cerevisiae. Perhaps surprisingly, nucleosome occupancy did not exhibit large, global variation between cell cycle phases. However, nucleosome occupancy at the promoters of cell cycle-regulated genes was reduced specifically at the cell cycle phase in which that gene exhibited peak expression, with the notable exception of S-phase genes. We present data that establish FAIRE as a high-throughput method for assaying nucleosome occupancy. For the first time in any system, nucleosome occupancy was mapped genome-wide throughout the cell cycle. Fluctuation of nucleosome occupancy at promoters of most cell cycle-regulated genes provides independent evidence that periodic expression of these genes is controlled mainly at the level of transcription. The promoters of G2/M genes are distinguished from other cell cycle promoters by an unusually low baseline nucleosome occupancy throughout the cell cycle. This observation, coupled with the maintenance throughout the cell cycle of the stereotypic nucleosome occupancy states between coding and non-coding loci, suggests that the largest component of variation in nucleosome occupancy is "hard wired," perhaps at the level of DNA sequence.

Cell Adhesion Molecules↗

PubMed1993

An approximate model and empirical energy function for solute interactions with a water-phosphatidylcholine interface.

An empirical model of a liquid crystalline (L alpha phase) phosphatidylcholine (PC) bilayer interface is presented along with a function which calculates the position-dependent energy of associated solutes. The model approximates the interface as a gradual two-step transition, the first step being from an aqueous phase to a phase of reduced polarity, but which maintains a high enough concentration of water and/or polar head group moieties to satisfy the hydrogen bond-forming potential of the solute. The second transition is from the hydrogen bonding/low polarity region to an effectively anhydrous hydrocarbon phase. The "interfacial energies" of solutes within this variable medium are calculated based upon atomic positions and atomic parameters describing general polarity and hydrogen bond donor/acceptor propensities. This function was tested for its ability to reproduce experimental water-solvent partitioning energies and water-bilayer partitioning data. In both cases, the experimental data was reproduced fairly well. Energy minimizations carried out on beta-hexyl glucopyranoside led to identification of a global minimum for the interface-associated glycolipid which exhibited glycosidic torsion angles in agreement with prior results (Hare, B.J., K.P. Howard, and J.H. Prestegard. 1993. Biophys. J. 64:392-398). Molecular dynamics simulations carried out upon this same molecule within the simulated interface led to results which were consistent with a number of experimentally based conclusions from previous work, but failed to quantitatively reproduce an available NMR quadrupolar/dipolar coupling data set (Sanders, C.R., and J.H. Prestegard. 1991. J. Am. Chem. Soc. 113:1987-1996). The proposed model and functions are readily incorporated into computational energy modeling algorithms and may prove useful in future studies of membrane-associated molecules.

Biophysical Phenomena↗

PubMed2006

Interrater and intrarater reliability in the evaluation of velopharyngeal insufficiency within a single institution.

OBJECTIVE: To explore the interrater and intrarater reliability in nasoendoscopic assessment of velopharyngeal (VP) function using the standardized reporting method described by Golding-Kushner within a single institution. DESIGN: Prospective blinded study. SETTING: Academic, tertiary care, pediatric hospital. PARTICIPANTS: Six health care providers (2 pediatric otolaryngology faculty members, 2 pediatric otolaryngology fellows, and 2 speech pathologists) independently rated 50 videotaped nasoendoscopy segments twice. The segments on the videotape were obtained in a clinical setting. MAIN OUTCOME MEASURES: The Golding-Kushner rating system was used to rate VP function. Raters described VP closure quantitatively by rating palatal and lateral pharyngeal wall movement for each segment. They also qualitatively described characteristics of the VP gap, rated gap size as none, small, medium, or large, and estimated the percentage gap size relative to the resting position. Reliability coefficients were calculated for the data sets. RESULTS: Fairly good interrater and intrarater reliability was seen in the quantitative measures. Faculty otolaryngologists rated segments more similarly to each other than did pediatric otolaryngology fellows, but intrarater reliability was similar for both the experienced and less experienced otolaryngologists. Less consistency was seen in the ratings of the speech pathologists. Raters tended to rate with less consistency when describing qualitative characteristics of the VP gap than when making quantitative measurements. CONCLUSIONS: The Golding-Kushner scale is a reasonably reliable tool for reporting nasoendoscopic findings at our institution. However, these data also indicate that there exists room for improvement and that rater training may increase reliability.

Adolescent↗

PubMedDate not supplied

Reliability of homeless women's reports: concordance between hair assay and self report of cocaine use.

BACKGROUND: To assess the concordance of homeless women's self-reported drug use with objective data. OBJECTIVE: To determine whether objective data (e.g., hair assays) are necessary supplements to self reports in assessing homeless women's cocaine use. METHOD: Self reports of cocaine use by 1,037 homeless women were compared to objective data based on radioimmunoassay of hair; independent correlates of cocaine use and underreporting were assessed using logistic regression. RESULTS: Forty-two percent of the women self-reported cocaine use in the past 6 months, whereas 49% had positive hair assays. Over 25% underreported cocaine use; however, underreporting decreased as hair cocaine levels increased. Predictors of underreporting included being Latino, younger and living primarily in shelters. Nevertheless, independent predictors of self-reported cocaine use and positive hair assays were identical. CONCLUSION: Homeless women's self-reports of cocaine use are fairly accurate. Objective data are particularly critical for assessing cocaine use among subgroups who are fearful of sanctions or use cocaine relatively infrequently or in smaller amounts.

Adult↗

PubMed2003

Probabilistic analysis indicates discordant gene trees in chloroplast evolution.

Analyses of whole-genome data often reveal that some genes have evolutionary histories that diverge from the majority phylogeny estimated for the entire genome. We present a probabilistic model that deals with heterogeneity among gene trees, implement it via the Gibbs sampler, and apply it to the plastid genome. Plastids and their genomes are transmitted as a single block without recombination, hence homogeneity among gene trees within this genome is expected. Nevertheless, previous work has revealed clear heterogeneity among plastid genes (e.g., Delwiche and Palmer 1996). Other studies, using whole plastid genomes of various algae and land plants, found little additional heterogeneity (Martin et al. 1998; Adachi et al. 2000). We augment the earlier studies by using a data set of 14 taxa: 6 land plants, 2 green algae, a diatom, 2 red algae and a cryptophyte, the cyanelle of the glaucocystophyte Cyanophora, and the blue-green alga Synechocystis as an outgroup. Contrary to the earlier analyses, we cannot find even a single, dominant consensus tree. Therefore, we formulate a probabilistic model that divides the genes into two sets: those that follow the consensus tree and those that have independent gene trees. No particular tree is supported by more than three-fourths of the genes. But the set of genes that follows a certain tree is fairly independent of data processing and the method of analysis. With one possible exception, we find no evidence for collinear or functionally related genes to follow similar trees. The phylogenetic pattern also seems independent of bias in amino acid composition. Among possible explanations for the observed phenomenon, the hypothesis that different genes have different covarion structures is difficult to assess. But gene duplication may be possible through the inverted or direct repeat regions, while horizontal gene transfer seems less likely. In contrast to green algae and land plants, inverted repeat regions in red algae and in Cyanophora show abundant differences among the copies. Thus, genes may get duplicated when they are recruited into the inverted repeat region and one of the two copies may be lost after leaving the inverted repeat region.

Chloroplasts↗

PubMed2002

A direct approach to estimating surfaces in tomographic data.

Under ideal circumstances, the inverse of the radon transform is computable, and sequences of measured projections are sufficient to obtain accurate estimates of volume densities. In situations where the sinogram data is incomplete, the radon transform is noninvertable, and attempts to reconstruct greyscale density values result in reconstruction artifacts that can undermine the effectiveness of subsequent processing. This paper presents a direct approach to the segmentation of incomplete tomographic data. The strategy is to impose a fairly simple model on the data, and treat segmentation as a problem of estimating the interface between two substances of somewhat homogeneous density. The segmentation is achieved by simultaneously deforming a surface model and updating density parameters in order to achieve a best fit between the projected model and the measured sinograms. The deformation is implemented with level-set surface models, calculated at the resolution of the input data. Relative to previous work, this paper makes several contributions. First is a proper derivation of the deformation of surface models that move according to a gradient descent on a likelihood measure. We also present a series of computational innovations that make this direct surface-fitting approach feasible with state-of-the-art computers. Another contribution is the demonstration of the effectiveness of this approach on under-constrained tomographic problems, using both simulated and real datasets.

Algorithms↗

PubMed2001

Using student-collected practice data as a teaching tool.

Research is an intimidating prospect for many students. This brief and fairly simple foray into data collection and analysis did not convince all students to embrace research. It did, however, entice many to consider how to incorporate data collection into their own beginning practices. Students who had stated their aversion to research found themselves arguing for the necessity of data collection to provide evidence for practice changes. There were also students who found the experience yet another busywork paper trail invented by the faculty. They resented the time and effort required for completion of another form during their busy clinical experiences. Other students remained adamantly opposed to considering any changes in what they saw as "appropriate" practice despite evidence to the contrary. An ongoing goal of education is to facilitate lifelong learning and investigation into clinical questions. The faculty plan to survey the graduates to ascertain what data collection efforts, if any, they are currently using. The educational program described in this project closed in December 1998 because of funding restrictions. One of the faculty in this project (Carr) and current colleagues are continuing to use the NMCDS to encourage students to examine and analyze their own practices. An additional use of the data set is for student-initiated research projects that focus on specific clinical questions. One faculty member was part of an effort to institute a similar project in a master's-based nurse-midwifery education program. That database has currently provided data for two master's degree projects. The uses of the NMCDS are not limited to graduate students or advanced practice clinicians. The tool is being used in an undergraduate maternity nursing clinical course to assist students in seeing differences in practice and the possible reasons for those differences. The Division of Research of the ACNM has sponsored the development of similar data collection tools for both ambulatory prenatal and well-woman care. The wellwoman tool is currently in the pilot stage (1999), and will be refined and further tested this year. The use of these data collection tools by advanced practice nurses would provide a wealth of data for both policy setting and clinical research. Educational programs frequently combine coursework for various advanced practice nursing pathways, and nurse-midwifery and nurse practitioner students would benefit from jointly focusing on practice patterns and participating in the analysis of student-collected data. The standardized tools for intrapartum, well-woman care, and antepartum care will be available to all of the 50 ACNM education programs as well as to practicing clinicians.

California↗

PubMed1996

Large bowel adenomas: markers of risk and endpoints.

In many large bowel chemoprevention trials adenomas have a double duty: they are used to identify subjects at risk for large bowel neoplasia, and also serve as endpoints. Many features of adenomas make them suitable for these tasks. Patients with adenomas are fairly numerous and easy to identify; further, the 'adenoma-carcinoma' sequence suggests that adenomas are logical endpoints. The high recurrence risk among adenoma patients means that a relatively modest number of subjects will suffice for adequate statistical power. The are some limitations to the use of adenomas, however. There is clearly heterogeneity of risk for subsequent cancer. Patients with only small adenomas may have rates of colorectal cancer that are not much greater than those of the general population. Certainly subjects with large adenomas, and those with villous or highly dysplastic adenomas have a higher risk. Often, one would chose the high-risk patients for preventive interventions. Such a strategy makes sense from a risk-benefit point of view. However, from a population perspective, such a strategy may well have only a minor impact on the overall colorectal cancer burden. For more complete population-based prevention, efforts will have to be directed to the numerous individuals who are each at small risk, but who collectively account for most colorectal cancer. For this preventive approach, patients with any adenoma would certainly be part of the target population, and so are sensible subjects in chemoprevention trials. There are similar complexities in consideration of the use of adenomas as endpoints of chemoprevention trials. The adenomas that occur in prevention trials are generally small, and may not be associated with a greatly increased cancer risk. The issue for chemoprevention trials however, is not whether the endpoints are truly intermediate in the causal chain-but whether the intervention under study alters the adenoma recurrence risk to the same extent as it does for colorectal cancer risk. This is a difficult matter to verify, but the limited data available are encouraging. The epidemiology of colorectal adenomas (largely small adenomas) is similar in many regards to that for colorectal cancer itself. Thus to the extent that data are available, one can tentatively conclude that external influences affect adenomas and colorectal cancer similarly. To date, more than ten adenoma prevention trials have reported results. The data have been fairly consistent. Vitamin C (with or without vitamin E) has provided at most a modest protective benefit, except in one small trial in which it was combined with vitamin E and preformed vitamin A. beta-Carotene seems to be without any effect, and interventions to increase fiber and decrease fat intake have not indicated substantial effects. On the other hand, trials among familial polyposis patients have provided evidence for an impact of nonsteroidal anti-inflammatory drugs. Studies in progress have the potential to clarify greatly the preventive potential of the currently promising-but yet unproven-chemopreventive regimens.

Adenoma↗

PubMedDate not supplied

Detection of extraprostatic prostate cells utilizing reverse transcription-polymerase chain reaction.

This article reviews the utility of reverse transcription-polymerase chain reaction (RT-PCR) in prostate cancer. RT-PCR aims to detect occult micrometastases in non-prostatic sites. Due to its exquisite analytical sensitivity, RT-PCR is able to amplify and detect even low-level, prostate-specific messages present at these extraprostatic sites. In recent years, a fair amount of data on the clinical utility of the technique had been reported. The target tissues under investigation are peripheral blood, bone marrow aspirate, and lymph nodes. Favorite markers of choice are prostate-specific antigen (PSA), prostate-specific membrane antigen (PSMA), and human glandular kallikrein-2 (hK2). False positives among negative controls are low. For the most part, RT-PCR is inadequate in detecting tumor cells in the peripheral blood from patients who are known to have metastatic prostate cancer. All studies showed that RT-PCR could detect PSA, PSMA or hK2 mRNAs in the circulation of patients who have organ-confined or extraprostatic disease. Most studies showed that RT-PCR utilizing current markers could not be used as a prospective test to diagnose prostate cancer. However, a few studies also showed that the detection rate could be predictive and sensitive enough to differentiate patients with organ-confined disease from those with extraprostatic disease. Data from PSA- or PSMA-RT-PCR using lymph nodes as the tissue source is more encouraging. RT-PCR was able to detect PSA and/or PSMA positive samples that have not been detected by conventional pathology.

Antigens, Surface↗

PubMedDate not supplied

Mixed-longitudinal analysis of growth data from Malian adolescent girls: evidence for compensatory gain?

Cross-sectional data have previously indicated poor growth and development among adolescent girls in Mali. These data have shown that Malian girls are shorter and lighter than their United States female counterparts. Many studies suggest that this evidence of poor growth and development is due to a combination of poor nutrient intake, high-energy expenditure, and poor access to health care. At adolescence, individuals rarely follow a standard pattern of growth due to different biological timetables and expressions of pubertal growth. By examining velocity of growth, researchers can recognize developmental patterns such as compensatory gain. This study examines the growth rates of Malian girls over a 6-month period. Anthropometric data were collected from a total of 1,045 adolescent girls ages 10-17 years. Height and weights were collected twice from the Segou Coura community in the town of Segou and from the Dioro Arrondissement in 1997. From these data, mixed longitudinal analyses were conducted. Both the height and weight velocity data showed patterns of delayed growth rates when compared with American girls. Although Malian girls are similar to American girls in that they tend to reach their peak height velocity at age 12, the Malian girls demonstrate a longer growth spurt than the American girls. This evidence of greater height velocity may be an indication of compensatory growth, or compensatory gain, and is partially supported from cross-sectional data. While these Malian data do not show much evidence that certain stressors are relieved during adolescence, only more extensive longitudinal data can more fairly examine the issue.

Adolescent↗

PubMed1994

Tensin: a potential link between the cytoskeleton and signal transduction.

Cytoskeletal proteins provide the structural foundation that allows cells to exist in a highly organized manner. Recent evidence suggests that certain cytoskeletal proteins not only maintain structural integrity, but might also be associated with signal transduction and suppression of tumorigenesis. Since the time of the discovery of tensin, a fair amount of data has been gathered which supports the notion that tensin is one such protein possessing these characteristics. In this review, we discuss recent studies that: (1) elucidate a role for tensin in maintenance of cellular structure and signal transduction; (2) implicate tensin as the anchor for actin filaments at the focal adhesion; (3) describe the phosphorylation of tensin; (4) describe potential targets for its Src homology region 2 domain; (5) describe the association between tensin and the nuclear protein p130; and (6) demonstrate that increased tensin expression in a cell line appears to reduce its transformation potential.

Actin Cytoskeleton↗

PubMedDate not supplied

Molecular diffusion, tissue microdynamics and microstructure.

Diffusion NMR is the only method available today that noninvasively provides information on molecular displacements over distances comparable to cell dimensions. This information can be used to infer tissue microstructure and microdynamics. However, data may be fairly difficult to interpret in biological tissues which differ markedly from the theoretical "infinite isotrope medium", as many factors may affect the NMR signal. The object of this paper is to analyze the expected effects of temperature, restriction, hindrance, membrane permeability, anisotropy and tissue inhomogeneity on the diffusion measurements. Powerful methods, such as q-space imaging, diffusion tensor imaging and diffusion spectroscopy of metabolites further enhance the specificity of the information obtained from diffusion NMR experiments.

Animals↗

PubMed1991

Pesticide personal protective clothing.

A fairly large established data base provides information on clothing worn by U.S. and Canadian farmers to work with pesticides, their attitudes and beliefs about pesticide risk, and clothing as a dermal barrier. Very limited similar data are available for farmers in less developed countries. Clearly, farmers perceive the benefits of pesticides to far exceed any risks. While few report poisoning symptoms, most believe that their usual work clothing offers a sufficient pesticide barrier, and few wear special-purpose protective clothing. Gloves of various materials, including cotton and leather, appear to be the major protective clothing item. Although farmers feel that their usual work clothing provides excellent protection, fabric penetration research does not support this. Shirting-weight fabrics offer some limited protection against light spray of field-strenght pesticides. Heavier-weight fabrics, such as denim and twill, are better barriers. With a heavier spray or a spill, usual work clothing does not give sufficient protection. Greater protection can usually be achieved with the use of a fluorocarbon finished fabric, such as Scotchgard or Zepel. Scotchgard can readily be applied at home. A durable-press finish does not appear to improve fabric's pesticide-barrier resistance and some data suggest that it may decrease barrier properties. A second alternative for increased protection is the use of a special-purpose fabric, such as a coated nonwoven or possibly Gore-Tex. Numerous other new "waterproof breathable" fabrics have recently come to the market. Many of these are finished or coated fabrics and one would expect them to be at least somewhat resistant to pesticides. However, they have not been tested. Wearing an additional layer also appears to be another clothing strategy to minimize exposure. Fabric penetration research also shows that pesticide formulation, volume or spray regime, concentration, and active ingredients influence the barrier properties of fabrics. Clothing evaluation studies have shown that protective clothing and coveralls of various materials and designs were effective in reducing exposure. Results of some of these studies suggested that the farmer's typical work clothing was more effective than fabric penetration results suggested. This apparent conflict is not surprising, given the methods used in both types of research. The field studies use pads placed in various areas under the clothing. This method assumes that exposure is uniform over entire body regions. But fluorescent tracer research has shown that this is not a valid assumption (DeJonge et al. 1985; Fenske 1988). Also, the way in which the pads are attached may make a difference, although no research has examined this issue.(ABSTRACT TRUNCATED AT 400 WORDS)

Agricultural Workers' Diseases↗