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PubMed2003

Proteolysis on Reggianito Argentino cheeses manufactured with natural whey cultures and selected strains of Lactobacillus helveticus.

Reggianito Argentino cheese is traditionally manufactured with whey starter cultures that provide typical and intense flavor but can cause poor quality standardization. In this study, the influence of natural and selected starters on Reggianito Argentino cheese proteolysis was investigated. Cheeses were manufactured with three strains of Lactobacillus helveticus (SF133, SF138 and SF209) cultured individually in sterile whey and used as single or mixed starters. Control cheeses were made with natural whey starter culture. Cheeses were analyzed to determine gross composition, as well as total thermophilic lactic flora. Proteolysis was assessed by N fractions, electrophoresis and liquid chromatography. Gross composition of the cheeses did not significantly differ, while viable starter cell counts were lower for cheeses made with strain SF209 alone or combined with other strains. Soluble N at pH 4.6 was the same for cheeses made with natural or selected starters, but soluble N in 12% trichloroacetic acid and 2.5% phosphotungstic acid was significantly higher in cheeses made with starters containing strain SF209. Nitrogen fractions results indicated that natural whey starter cultures could be replaced by several starters composed of the selected strains without significant changes to proteolysis patterns. Starter cultures prepared only with SF209 or with the three selected L. helveticus strains produced cheese products with significantly more proteolysis than control cheeses. Chromatographic profiles analyzed by principal components showed that three main peaks on chromatograms, presumptively identified as Tyr, Phe, and Trp, explained most of variability. Principal component scores indicated that cheese samples were grouped by ripening time, which was confirmed by linear discriminant analysis. On the contrary, samples did not cluster by Lactobacillus strain or type of starter.

Amino Acids↗
PubMed1994

Relationship of five anthropometric measurements at age 18 to radiation dose among atomic bomb survivors exposed in utero.

Five body measurements--standing height, body weight, sitting height, chest circumference and intercristal diameter--of 18-year-old atomic bomb survivors exposed in utero in Hiroshima and Nagasaki were analyzed in relation to DS86 uterine dose. Age in utero was divided into four periods: 0-7, 8-15, 16-25 and > or = 26 weeks. This categorization is based upon the study of radiation-induced brain damage. The linear regression analyses for these five variables showed significant decreases with increasing dose. The regression coefficients were -2.65 cm/Gy for standing height, -2.46 kg/Gy for body weight, -0.92 cm/Gy for sitting height, -1.37 cm/Gy for chest circumference and -0.32 cm/Gy for intercristal diameter. The multivariate test statistic for the overall dose effect on five body measurements was significant, but the interaction between dose and gestational period was not significant. Principal-component analysis was applied to the five variables. For the first-component scores, the dose effect was significant, but the interaction between dose and gestational period was not significant. For the second-component scores, the dose effect was significant specifically at 0-7 weeks. The radiation dose effect on the second principal component found at 0-7 weeks of gestation suggests that malformations occur in this period.

Adolescent↗
PubMed1987

Construction and validation of a questionnaire to measure the health beliefs of general practice patients.

The health belief model has been widely used as a conceptual framework for understanding and explaining compliance behaviour. A weakness characterizing work in the area has been lack of standardization of measurement of the components of the health belief model. This paper describes the development and validation of a questionnaire to measure these components. The questionnaire was designed for use with general practice patients who have a wide range of different illnesses, therefore the nature of the patients' illness is not mentioned in the content of the items. Principal components analysis was used to determine the dimensions underlying patients' beliefs. Principal components analysis and application of Cronbach's alpha statistic identified four reliable sub-scales of the questionnaire. The sub-scales measured patient's beliefs about: the threat caused by illness, the efficacy of traditional medical care, the way illness is dealt with and the barriers to taking medications.

Attitude to Health↗
PubMedDate not supplied

An exploratory factor analysis of existential suffering in Japanese terminally ill cancer patients.

To determine an underlying factorial structure of existential distress in Japanese terminally ill cancer patients, a principal components analysis was performed on 162 Japanese hospice inpatients. Existential distress commonly identified was dependency (39%), meaninglessness in present life (37%), hopelessness (37%), burden on others (34%), loss of social role functioning (29%), and feeling emotionally irrelevant (28%). By a factor analysis, three primary components accounted for 66% of the variance. 'Dependency' and 'loss of social role functioning' loaded highly on the first factor, which was interpreted as 'loss of autonomy'. 'Burden on others' and 'feeling emotionally irrelevant' loaded highly on the second component interpreted as 'lowered self-esteem', while 'hopelessness' loaded highly on the third factor. On the other hand, 'meaninglessness in present life' loaded equally on all three components, and was significantly associated with other distress. In conclusion, existential suffering of Japanese terminally ill cancer patients has three principal components: loss of autonomy, lowered self-esteem, and hopelessness. It is also suggested that meaninglessness in present life would be an underlying theme in patients' spirituality.

Adult↗
PubMed2001

Characterization of cocoa butter and cocoa butter equivalents by bulk and molecular carbon isotope analyses: implications for vegetable fat quantification in chocolate.

The fatty acids from cocoa butters of different origins, varieties, and suppliers and a number of cocoa butter equivalents (Illexao 30-61, Illexao 30-71, Illexao 30-96, Choclin, Coberine, Chocosine-Illipé, Chocosine-Shea, Shokao, Akomax, Akonord, and Ertina) were investigated by bulk stable carbon isotope analysis and compound specific isotope analysis. The interpretation is based on principal component analysis combining the fatty acid concentrations and the bulk and molecular isotopic data. The scatterplot of the two first principal components allowed detection of the addition of vegetable fats to cocoa butters. Enrichment in heavy carbon isotope ((13)C) of the bulk cocoa butter and of the individual fatty acids is related to mixing with other vegetable fats and possibly to thermally or oxidatively induced degradation during processing (e.g., drying and roasting of the cocoa beans or deodorization of the pressed fat) or storage. The feasibility of the analytical approach for authenticity assessment is discussed.

Carbon Isotopes↗
PubMed2004

Validation of Horne and Ostberg morningness-eveningness questionnaire in a middle-aged population of French workers.

As suggested by the authors, the Horne and Ostberg morning/evening questionnaire (MEQ) has never been adapted to evaluate a nonstudent population. The purpose of this study was to validate this MEQ in a sample of middle-aged workers by modifying only the cutoffs. It was administered in 566 non-shift-workers aged 51.2 to 3.2 years who presented no sleep disorders. According to the Home and Ostberg classification, the sample consisted of 62.1% morning type, 36.6% neither type, and 2.2% evening type. Multiple correspondence analysis, which determines the principal components, was performed on all MEQ items. Then an ascending hierarchical classification was applied to determine 3 clusters from these principal components. On the basis of these 3 clusters, new cutoffs were determined: evening types were considered as scoring under 53 and morning types above 64, thus giving 28.1% morning type, 51.7% neither type, and 20.2% evening type. As an external validation, eveningness was associated with later bedtime and waking-up time (more pronounced at the weekend), greater need for sleep, larger daily sleep debt, greater morning sleepiness, and ease of returning to sleep in the early morning. A positive correlation between age and morningness was again found. This study confirms that "owls" are not rare in a middle-aged sample. We conclude that this adapted MEQ could be useful when investigating age-related changes in sleep.

Biological Clocks↗
PubMed2005

Biomarker metabolites capturing the metabolite variance present in a rice plant developmental period.

BACKGROUND: This study analyzes metabolomic data from a rice tillering (branching) developmental profile to define a set of biomarker metabolites that reliably captures the metabolite variance of this plant developmental event, and which has potential as a basis for rapid comparative screening of metabolite profiles in relation to change in development, environment, or genotype. Changes in metabolism, and in metabolite profile, occur as a part of, and in response to, developmental events. These changes are influenced by the developmental program, as well as external factors impinging on it. Many samples are needed, however, to characterize quantitative aspects of developmental variation. A biomarker metabolite set could benefit screening of quantitative plant developmental variation by providing some of the advantages of both comprehensive metabolomic studies and focused studies of particular metabolites or pathways. RESULTS: An appropriate set of biomarker metabolites to represent the plant developmental period including the initiation and early growth of rice tillering (branching) was obtained by: (1) determining principal components of the comprehensive metabolomic profile, then (2) identifying clusters of metabolites representing variation in loading on the first three principal components, and finally (3) selecting individual metabolites from these clusters that were known to be common among diverse organisms. The resultant set of 21 biomarker metabolites was reliable (P = 0.001) in capturing 83% of the metabolite variation in development. Furthermore, a subset of the biomarker metabolites was successful (P = 0.05) in correctly predicting metabolite change in response to environment as determined in another rice metabolomics study. CONCLUSION: The ability to define a set of biomarker metabolites that reliably captures the metabolite variance of a plant developmental event was established. The biomarker metabolites are all commonly present in diverse organisms, so studies of their quantitative relationships can provide comparative information concerning metabolite profiles in relation to change in plant development, environment, or genotype.

Amino Acids↗
PubMed2000

Color signals in natural scenes: characteristics of reflectance spectra and effects of natural illuminants.

Multispectral images of natural scenes were collected from both forests and coral reefs to represent typical, complex scenes that might be viewed by modern animals. Both reflectance spectra and modeled visual color signals in these scenes were decorrelated spectrally by principal-component analysis. Nearly 98% of the variance of reflectance spectra and color signals can be described by the first three principal components for both forest and coral reef scenes, which implies that three well-designed visual channels can recover almost all of the spectral information of natural scenes. A variety of natural illuminants affects color signals of forest scenes only slightly, but the variation in ambient irradiance spectra that is due to the absorption of light by water has dramatic influences on the spectral characteristics of coral reef scenes.

Animals↗
PubMed1994

Principal descriptors of body condition score in Holstein cows.

The objective of this study was to assess objectively the ability of observers to assess body condition of dairy cows. Four observers independently assigned a body condition score (five-point scale, .25 increments) and described the appearance of seven body regions of 225 Holstein cows. Areas described were the thurl region, ischial and ileal tuberosities, ilio-sacral and ischio-coccygeal ligaments, transverse processes of the lumbar vertebrae, and spinous processes of the lumbar vertebrae. An absolute body condition score was designated for each cow based on the modal body condition score for all observers. If there was no modal body condition score, the mean score was used for the absolute body condition score. Statistical analysis of principal components was used to examine the relationship between body region description and absolute body condition score. Descriptions of body regions were highly correlated across all absolute body condition scores. Four principal component vectors explained 83.6% of the variation of the body region correlation matrix. The first principal latent vector accounted for 55% of the variation and was uniformly correlated with all body regions. Analysis of variance of first principal latent vector as the dependent variable and absolute body condition score as the class variable indicated that body condition could be separated into .25 units between 2.5 and 4.0, inclusively. Below 2.5 and > 4.0, body condition could only be separated by .5 units. Distinct changes in specific body regions were associated with change in absolute body condition score. Observers agreed with the absolute score 58.1% of the time, deviating by .25 units 32.6% of the time. A body condition score can be given to a cow based on principal descriptors of specific body regions between 2.5 and 4.0 by .25 units.

Adipose Tissue↗
PubMed1999

[Heterogeneities of ventricular repolarization and vulnerability to arrhythmia. How to detect them with noninvasive methods?].

Vulnerability to arrhythmias can be influenced by two conditions: a dynamic (beat-to-beat) variation of repolarization sequence, and a state of heterogeneity of repolarization, i.e. a greater than normal dispersion of recovery time. The first condition is well reflected by T-wave alternans, a phenomenon characterized by alternation on every other beat basis of amplitude and morphology of T waves. Experimental studies provided evidences of close temporal correlations between ischemia-induced alternans, dispersion of repolarization and susceptibility to ventricular fibrillation. Gross T-wave alternans can be occasionally observed in patients with long QT syndrome or during acute ischemia before the onset of arrhythmias. Recent studies have demonstrated that measurement of microvolt level T-wave alternans at rest and during exercise is a promising technique for the identification of patients at risk of ventricular arrhythmias and sudden death. A state of repolarization inhomogeneity can be revealed by methods which analyze a single cardiac beat. The QT dispersion, defined as the difference between maximum and minimum QT interval measured at 12 lead ECG, is the most simple and widely used index of repolarization inhomogeneity. The major limitation is that this measure cannot be related to the actual spatial heterogeneity of repolarization, since each surface lead reflects, in different degree, the electrical activity of the whole heart. The majority of studies reported that, in various pathological conditions, the QT dispersion is higher in patients with than without ventricular arrhythmias. On the other hand, a recent large prospective study in post-myocardial infarction patients failed to demonstrate the predictive value of QT dispersion, even when measured with the best available methodology. Body surface potential mapping has proven to be a useful method for detecting repolarization inhomogeneities not revealed by the analysis of conventional ECG leads. Different methods of analysis of the potential maps have been used. By applying principal component analysis of the ST-T waves, we computed the similarity index, defined as the ratio of the first principal component to the sum of all remaining components. A low value of similarity index suggests a high degree of repolarization inhomogeneity. The similarity index was found significantly lower in patients with idiopathic long QT syndrome and in patients with arrhythmogenic right ventricular dysplasia with episodes of ventricular tachycardia than in normal subjects. Future researches should aim at identifying novel reliable indices of repolarization inhomogeneity, first deduced from extensive body surface mapping, then possibly computed from digital recording of the 12 conventional leads.

Arrhythmias, Cardiac↗
PubMed1993

Behaviour in the novel environment predicts responsiveness to d-amphetamine in the rat: a multivariate approach.

The behaviour of rats in a novel environment was studied using a rapid time-sampling observation procedure followed by a principal component analysis (PCA) of the data. This approach revealed that novel environment behaviour can be described by two factors or principal components. The first factor comprised rearing, sniffing-up, ambulation and locomotion (photocell counts), and was termed "Escape". The second factor, which had high positive loadings of sniffing-down and locomotion and a high negative loading of immobility, was termed "Exploration". The scores of individual rats on the "Escape" factor predicted the stimulatory effect of acutely administered d-amphetamine (1.5mg/kg) on unconditioned behaviour. "Escape" high responders (HRs) showed more behavioural stimulation than "Escape" low responders (LRs). However, the locomotor stimulatory response of both groups increased after long-term, periodic administration of d-amphetamine and drug discrimination training, such that the level of drug-induced locomotor activity was now equivalent for the two groups. The same rats were tested twice with various doses of d-amphetamine after being trained to discriminate this drug (0.5mg/kg) from saline. "Escape" HRs were less sensitive than "Escape" LRs to the discriminative effects of 0.125-0.25mg/kg d-amphetamine. In contrast to these findings, "Exploration" HRs and LRs were not different on any of the dependent measures described above. These results are discussed in relation to the possibility that "Escape" factor scores are an indication of an animal's responsivity to novelty-induced stress. If this is the case, then animals which are more susceptible to the effects of novelty stress are more sensitive to the locomotor stimulating effects of acute d-amphetamine, but less sensitive to the cueing properties of low doses of this drug.

Journal Article↗
PubMed1995

Structural responses of Japanese quail intestine to different diets.

Japanese quail were fed five diets of different nutrient composition and the structural responses of the intestinal tract were measured. Six morphometric variables were recorded. Depending on the diet, we found drastic changes in those factors affecting surface dimensions of the mucosa epithelium and the thickness of the muscle layers of the intestinal wall. We performed a principal component analysis to describe the interrelationship among the different variables and the response of the intestine to different diets. Two principal components were found accounting for surface and muscle layers respectively. Cytokinetic experiments (TdR/BrdU double labelling of S-phase nuclei) were performed to estimate the epithelial turnover time. We found a labelling index between 1.5% and 3% depending on the segment of the intestine. The length of the S-phase was found to be constant along the gut at 6.5 (+/- 2.5) hours. The epithelial turnover time, necessary to rebuild and adjust the intestine, ranged between 10 and 17 days. We discuss evolutionary ecology perspectives as well as applied poultry aspects of the data.

Animal Feed↗
PubMed2000

Localization of agonist and competitive antagonist binding sites on nicotinic acetylcholine receptors.

Identification of all residues involved in the recognition and binding of cholinergic ligands (e.g. agonists, competitive antagonists, and noncompetitive agonists) is a primary objective to understand which structural components are related to the physiological function of the nicotinic acetylcholine receptor (AChR). The picture for the localization of the agonist/competitive antagonist binding sites is now clearer in the light of newer and better experimental evidence. These sites are located mainly on both alpha subunits in a pocket approximately 30-35 A above the surface membrane. Since both alpha subunits are identical, the observed high and low affinity for different ligands on the receptor is conditioned by the interaction of the alpha subunit with other non-alpha subunits. This molecular interaction takes place at the interface formed by the different subunits. For example, the high-affinity acetylcholine (ACh) binding site of the muscle-type AChR is located on the alphadelta subunit interface, whereas the low-affinity ACh binding site is located on the alphagamma subunit interface. Regarding homomeric AChRs (e.g. alpha7, alpha8, and alpha9), up to five binding sites may be located on the alphaalpha subunit interfaces. From the point of view of subunit arrangement, the gamma subunit is in between both alpha subunits and the delta subunit follows the alpha aligned in a clockwise manner from the gamma. Although some competitive antagonists such as lophotoxin and alpha-bungarotoxin bind to the same high- and low-affinity sites as ACh, other cholinergic drugs may bind with opposite specificity. For instance, the location of the high- and the low-affinity binding site for curare-related drugs as well as for agonists such as the alkaloid nicotine and the potent analgesic epibatidine (only when the AChR is in the desensitized state) is determined by the alphagamma and the alphadelta subunit interface, respectively. The case of alpha-conotoxins (alpha-CoTxs) is unique since each alpha-CoTx from different species is recognized by a specific AChR type. In addition, the specificity of alpha-CoTxs for each subunit interface is species-dependent. In general terms we may state that both alpha subunits carry the principal component for the agonist/competitive antagonist binding sites, whereas the non-alpha subunits bear the complementary component. Concerning homomeric AChRs, both the principal and the complementary component exist on the alpha subunit. The principal component on the muscle-type AChR involves three loops-forming binding domains (loops A-C). Loop A (from mouse sequence) is mainly formed by residue Y(93), loop B is molded by amino acids W(149), Y(152), and probably G(153), while loop C is shaped by residues Y(190), C(192), C(193), and Y(198). The complementary component corresponding to each non-alpha subunit probably contributes with at least four loops. More specifically, the loops at the gamma subunit are: loop D which is formed by residue K(34), loop E that is designed by W(55) and E(57), loop F which is built by a stretch of amino acids comprising L(109), S(111), C(115), I(116), and Y(117), and finally loop G that is shaped by F(172) and by the negatively-charged amino acids D(174) and E(183). The complementary component on the delta subunit, which corresponds to the high-affinity ACh binding site, is formed by homologous loops. Regarding alpha-neurotoxins, several snake and alpha-CoTxs bear specific residues that are energetically coupled with their corresponding pairs on the AChR binding site. The principal component for snake alpha-neurotoxins is located on the residue sequence alpha1W(184)-D(200), which includes loop C. In addition, amino acid sequence 55-74 from the alpha1 subunit (which includes loop E), and residues gammaL(119) (close to loop F) and gammaE(176) (close to loop G) at the low-affinity binding site, or deltaL(121) (close to the homologous region of loop G) at the high-affinity binding site, are i

Animals↗
PubMed2003

Detection of odour emissions from a composting facility using a QCM sensor array.

Odour emissions from a composting facility were detected by using a quartz crystal microbalance (QCM) sensor array. The array consists of six sensor elements, which were coated with different materials. A series of tests under field conditions showed that considerable sensor frequency changes were detected during the compost-turning period. Using principal component analysis, it was found that more than 90% of the data variance could still be explained by use of two principal components.

Chemistry Techniques, Analytical↗
PubMed1988

Lateralization patterns of verbal stimuli processing assessed by reaction time and event-related potentials in schizophrenic patients.

Event-related potentials (ERPs), reaction time (RT), number of errors and number of omissions were recorded by using a visual target detection paradigm in which consonant pairs were presented in a central and in a lateral condition. Fourteen DSM III drug-free schizophrenics and 19 healthy subjects took part in the study. All of them were male and right-handed. Independent principal component analysis and varimax rotation were performed for each condition. Separate ANOVAs were performed on factor scores computed for each rotated principal component. In the central condition, schizophrenic patients showed a reduction of the late positive complex (LPC) peak with respect to normal controls, and this reduction was associated with a predominant negative symptomatology. No pattern of lateral asymmetry was found in either group for behavioural and ERP measures. For the lateral condition, a significant advantage of the right visual field (RVF) presentation (shorter RT and larger LPC peak for RVF stimuli) was observed in normal subjects, while no visual field effect on these two measures was detected in schizophrenics. Significant differences were found between the two groups on both behavioural and ERP measures for the RVF only. Furthermore, two ERP components showed a marked advantage of the left visual field in the patient group, associated with a predominance of positive symptoms in the clinical picture.

Adult↗
PubMedDate not supplied

Comparative structural connectivity spectra analysis (CoSCoSA) models of steroid binding to the corticosteroid binding globulin.

A three-dimensional quantitative spectrometric data-activity relationship (3D-QSDAR) model was developed that is built by combining NMR spectral information with structural information in a 3D-connectivity matrix. The 3D-connectivity matrix is built by displaying all possible carbon-to-carbon connections with their assigned carbon NMR chemical shifts and distances between the carbons. Selected 2D (13)C-(13)C COrrelation SpectroscopY (COSY) (through-bond nearest neighbors) and selected theoretical 2D (13)C-(13)C distance connectivity spectral slices from the 3D-connectivity matrix to produce a relationship among the spectral patterns for 30 steroids binding to corticosteroid binding globulin. We call this technique a comparative structural connectivity spectra analysis (CoSCoSA) modeling. A CoSCoSA principal component linear regression model based on the combination of (13)C-(13)C COSY and (13)C-(13)C distance spectra principal components (PCs) had an r(2) of 0.96 and a leave-one-out (LOO) cross-validation q(2) of 0.92. A CoSCoSA parallel distributed artificial neural network (PD-ANN) model based on the combination of (13)C-(13)C COSY and (13)C-(13)C distance spectra had an r(2) of 0.96, a leave-three-out q(3)(2) of 0.78, and a leave-ten-out q(10)(2) of 0.73. CoSCoSA modeling attempts to uniquely combine the quantum mechanics information from the NMR chemical shifts with internal molecular atom-to-atom distances into an accurate modeling technique. The CoSCoSA modeling technique has the flexibility and accuracy to outperform the cross-validated variance q(2) of previously published quantitative structure-activity relationship (QSAR), quantitative spectral data-activity relationship (QSDAR), self-organizing map (SOM), and electrotopological state (E-state) models.

Binding Sites↗
PubMed2000

Behavior of monosaccharides, phenolic compounds, and color of red wines aged in used oak barrels and in the bottle.

A red wine with appropriate basic quality characteristics for aging was stored in oak barrels for 12 months and then bottled and aged for a further 6 months. The same ambient conditions of temperature and humidity were maintained throughout the entire aging process. The barrels used were made from three different species of oak by four different cooperages and had been used for at least two years. Analysis of variance and principal component analysis were run on the values for hexoses, pentoses, total anthocyanins, ortho-diphenols, low- and high-polymer polyphenols, and color parameters to study the behavior of the monosaccharides and polyphenols in response to the factors of aging time, the oak variety employed, and the source cooperage where the barrels had been made. Time trends for all the phenolic components were directly related to aging time, with low-polymeric polyphenols (LPPs) being the most affected by wood type and source cooperage. Wine color was defined by a basic red color which decreased with aging time in the barrel and was altered by yellowish pigment components differing for each of the barrels in which oxidative aging took place and by increased stability of the blue copigments. Principal component analysis showed that samples of the same source wine aged in different barrels tended to be grouped together according to each of the aging intervals considered.

Color↗
PubMed1997

Defining primary care. Empirical analysis of the National Ambulatory Medical Care Survey.

OBJECTIVES: Efforts to contain health care costs have increased interest in defining which specialties provide primary care and in developing tools to assess the delivery of primary care services. METHODS: Using data from the 1985-1991 National Ambulatory Medical Care Surveys, the authors examined the activities of 29 physician specialty groups to determine whether the recent Institute of Medicine definition of primary care could be operationalized. Ten elements were identified that addressed comprehensiveness (first-contact care, a Herfindahl Index, previous contact for other problems, prevention, and care through the life cycle), coordination (referrals), continuity (any previous contact), and accessibility (care provided to black patients, those on Medicaid, and patients in rural areas). RESULTS: Principal component and factor analyses suggested that each element, except care through the life cycle, contributed to the construct of primary care. Principal component analysis enabled ordering of specialties according to their "primary careness," suggesting that specialties other than family/general practice, pediatrics, and internal medicine make significant contributions to primary care. Factor analysis suggested that two factors related to process and content underlie the definition of primary care and emphasize the importance of integration of services provided. This analysis provides a basis for further empirical work to develop measures of primary care performance. CONCLUSIONS: National surveys need to be modified to provide a more comprehensive assessment of primary care in the United States.

Ambulatory Care↗