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Primary cilia are sensory organelles built and maintained by intraflagellar transport (IFT) multiprotein complexes. Deletion of several IFT-B genes attenuates polycystic kidney disease (PKD) severity in juvenile and adult autosomal dominant polycystic kidney disease (ADPKD) mouse models. However, deletion of an IFT-A adaptor, Tulp3, attenuates PKD severity in adult mice only. These studies indicate that dysfunction of specific cilia components has potential therapeutic value. To broaden our understanding of cilia dysfunction and its therapeutic potential, we investigate the role of global deletion of an IFT-A gene, Ttc21b, in juvenile and adult mouse models of ADPKD. Both juvenile (postnatal day 21) and adult (six months of age) ADPKD mice exhibited kidney cysts, increased kidney weight/body weight ratios, lengthened kidney cilia, inflammation, and increased levels of the nutrient sensor, O-linked β-N-acetylglucosamine (O-GlcNAc). Deletion of Ttc21b in juvenile ADPKD mice reduced cortical collecting duct cystogenesis and kidney weight/body weight ratios, increased proximal tubular and glomerular dilations, but did not reduce cilia length, inflammation, nor O-GlcNAc levels. In contrast, Ttc21b deletion in adult ADPKD mice markedly attenuated kidney cystogenesis and reduced cilia length, inflammation, and O-GlcNAc levels. Thus, unlike IFT-B, the effect of Ttc21b deletion in mouse models of ADPKD is development-specific. Unlike an IFT-A adaptor, deleting Ttc21b in juvenile ADPKD mice is partially ameliorative. Thus, our studies suggest that different microenvironmental factors, found in distinct nephron segments and in developing versus mature stages, modify ciliary homeostasis and ADPKD pathobiology. Further, elevated levels of O-GlcNAc, which regulates cellular metabolism and ciliogenesis, may be a pathological feature of ADPKD.

Polycystic liver disease (PLD) is characterized by the growth of numerous biliary cysts and presents in patients with autosomal dominant polycystic kidney disease (ADPKD), causing significant morbidity. Interestingly, deletion of intraflagellar transport-B (IFT-B) complex genes in adult mouse models of ADPKD attenuates the severity of PKD and PLD. Here we examine the role of deletion of an IFT-A gene, Thm1, in PLD of juvenile and adult Pkd2 conditional knockout mice. Perinatal deletion of Thm1 resulted in disorganized and expanded biliary regions, biliary fibrosis, increased serum bile acids, and a shortened primary cilium on cytokeratin 19+ (CK19+) epithelial cells. In contrast, perinatal deletion of Pkd2 caused PLD, with multiple CK19+ epithelial cell-lined cysts, fibrosis, lengthened primary cilia, and increased Notch and ERK signaling. Perinatal deletion of Thm1 in Pkd2 conditional knockout mice increased hepatomegaly, liver necrosis, as well as serum bilirubin and bile acid levels, indicating enhanced liver disease severity. In contrast to effects in the developing liver, deletion of Thm1 alone in adult mice did not cause a biliary phenotype. Combined deletion of Pkd2 and Thm1 caused variable hepatic cystogenesis at 4 months of age, but differences in hepatic cystogenesis between Pkd2- and Pkd2;Thm1 knockout mice were not observed by 6 months of age. Similar to juvenile PLD, Notch and ERK signaling were increased in adult Pkd2 conditional knockout cyst-lining epithelial cells. Taken together, Thm1 is required for biliary tract development, and proper biliary development restricts PLD severity. Unlike IFT-B genes, Thm1 does not markedly attenuate hepatic cystogenesis, suggesting differences in regulation of signaling and cystogenic processes in the liver by IFT-B and -A. Notably, increased Notch signaling in cyst-lining epithelial cells may indicate that aberrant activation of this pathway promotes hepatic cystogenesis, presenting as a novel potential therapeutic target. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Polycystic liver disease (PLD) is characterized by the growth of numerous biliary cysts and presents in patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD), causing significant morbidity. Interestingly, deletion of intraflagellar transport-B (IFT-B) genes in adult mouse models of ADPKD attenuates severity of PKD and PLD. Here we examine the role of deletion of IFT-A gene, Thm1, in PLD of juvenile and adult Pkd2 conditional knock-out mice. Perinatal deletion of Thm1 results in disorganized and expanded biliary regions, biliary fibrosis, shortened primary cilia on CK19+ biliary epithelial cells, and reduced Notch signaling. In contrast, perinatal deletion of Pkd2 causes PLD, with multiple CK19+ biliary epithelial cell-lined cysts, fibrosis, lengthened primary cilia, and increased Notch and ERK signaling. Perinatal deletion of Thm1 in Pkd2 conditional knock-out mice increased hepatomegaly and liver necrosis, indicating enhanced liver disease severity. In contrast to effects in the developing liver, deletion of Thm1 in adult mice, alone and together with Pkd2, did not cause a biliary phenotype nor affect Pkd2-mutant PLD, respectively. However, similar to juvenile PLD, Notch and ERK signaling were increased in adult Pkd2-mutant cyst-lining cholangiocytes. Taken together, Thm1 is required for biliary tract development, likely by enabling Notch signaling, and proper biliary development restricts PLD severity. Unlike IFT-B genes, Thm1 does not affect hepatic cystogenesis, suggesting divergent regulation of signaling and cystogenic processes in the liver by IFT-B and –A. Notably, increased Notch signaling in cyst-lining cholangiocytes may indicate that aberrant activation of this pathway promotes hepatic cystogenesis, presenting as a novel potential therapeutic target.

Primary cilia are sensory organelles built and maintained by intraflagellar transport (IFT) multi-protein complexes. Deletion of different IFT-B genes attenuates polycystic kidney disease (PKD) severity in juvenile and adult Autosomal Dominant (AD) PKD mouse models, while deletion of an IFT-A adaptor, Tulp3, attenuates PKD severity in adult mice only. These studies indicate that dysfunction of specific cilia components has potential therapeutic value. To broaden our understanding of cilia dysfunction and its therapeutic potential, here we investigate the impact of global deletion of an IFT-A gene, Thm1, in juvenile and adult ADPKD mouse models. Both juvenile and adult models exhibited increased kidney weight:body weight (KW/BW) ratios, renal cysts, inflammation, lengthened renal cilia, and increased levels of the nutrient sensor, O-linked β-N-acetylglucosamine (O-GlcNAc). Thm1 deletion in juvenile ADPKD mice reduced KW/BW ratios and cortical collecting duct cystogenesis, but increased proximal tubular and glomerular dilations and did not reduce inflammation, cilia lengths, and O-GlcNAc signaling. In contrast, Thm1 deletion in adult ADPKD mice markedly attenuated renal cystogenesis, inflammation, cilia lengths, and O-GlcNAc. Thus, unlike IFT-B genes, the role of Thm1 deletion in ADPKD mouse models is development-specific. Unlike an IFT-A adaptor gene, deleting Thm1 in juvenile ADPKD mice is partially ameliorative. Our studies suggest that different microenvironmental factors found in distinct nephron segments and between developing and mature kidneys modify ciliary homeostasis and ADPKD pathobiology. Further, elevated levels of O-GlcNAc, which regulates cellular metabolism and ciliogenesis, may be a novel feature and critical regulator of certain key ADPKD pathological processes.

BACKGROUND: Obesity is a major and worldwide health problem in children. OBJECTIVES: The Early Childhood Obesity Prevention Program is a multi-component, randomized, controlled trial of a pilot community-focused obesity prevention program for mother/newborn dyads. METHODS: Underserved, mother/newborn dyads were recruited to receive a standard home visitation program (Nurturing Families Network, NFN) or an enhanced program (NFN+) that incorporated behavioural change strategies (e.g., goal-setting, problem-solving) and focused on six obesity-associated behaviours (breastfeeding, juice/sugar-sweetened beverages, solids, infant sleep, TV/screen time and soothability) with linkages to community resources. Weight-for-length (WFL) z-score and maternal diet were secondary outcomes. RESULTS: Fifty-seven dyads were recruited and 47 fully eligible dyads were enrolled (NFN = 21, NFN+ = 26). Forty-one (87.2%) were assessed at 6 months and 34 (72.3%) at 12 months. Retention at 12 months was higher for NFN+ dyads (84.6% vs. 56.1%, p = 0.04). NFN+ mothers were more likely to continue breastfeeding at 6 and 12 months vs. NFN mothers (p = 0.03 and 0.003, respectively), and at 12 months, NFN+ infants had fewer nocturnal awakenings (p = 0.04). There were no differences in other primary outcome measures or in WFL z-score at 6 or 12 months. CONCLUSIONS: A multi-component behavioural intervention increased breastfeeding duration and decreased nocturnal awakenings in infants of low-income families.

Background & objectives : Diabetes mellitus is a major public health problem worldwide. With the rising incidence of diabetes in India, it becomes particularly relevant to ascertain its prevalence in various ethnic groups. The objective of this study was to find out the presence of diabetes mellitus in the ′Dawoodi Bohra Youth Community′ and also to assess the factors responsible for it. Methods: A house-to-house study was conducted and 2179 subjects were questioned randomly; children below 18 yr of age were excluded. A questionnaire was given to each member and questions were also asked to test their level of awareness regarding diabetes which was graded on a 5-pointer scale where 1 meant ′very poor′ and 5-′excellent′. Diabetes was diagnosed using GOD-POD (oxidase-peroxidase) method according to the WHO criteria. Results: Total number of diabetic subjects found was 246 (11.29%) with a mean age of 60.21±10.91 years. The condition was more common in males (58.94%). The highest prevalence was recorded in the age group of 65-69 yr (22.01%) and none had diabetes in the age group 11-24 yr. p0 edigree analysis showed that 109 (44.30%) subjects had at least one affected relative and 23 (9.34%) had at least two diabetic family members; 52 were found to have parents with diabetes. On the 5-pointer scale, the overall care in diabetic subjects was 3.76±0.56 as compared to 2.86±0.60 in non-diabetic subjects ( p

We review briefly the performance of self-consistent mean field models in connection with exotic nuclei. Two variants are discussed, the Skyrme-Hartree-Fock (SHF) method and the relativistic mean-field (RMF) model. The basic properties are summarized. Applications to neutron rich Sn isotopes and to superheavy elements are discussed. As effects slightly beyond mean field, we present recent results on low lying 2 + excitations in Sn isotopes and in 186 Pb.

We present an analysis of two-proton shell gaps in Sn isotopes. As the theoretical tool we use self-consistent mean-field models, namely the relativistic mean-field model and the Skyrme-Hartree-Fock approach, both with two different pairing forces, a delta interaction (DI) model and a density-dependent delta interaction (DDDI). We investigate the influence of nuclear deformation as well as collective correlations and find that both effects contribute significantly. Moreover, we find a further significant dependence on the pairing force used. The inclusion of deformation plus correlation effects and the use of DDDI pairing provides agreement with the data., Comment: gzipped tar archiv containing LaTeX source, bibliography file (*.bbl), all figures as *.eps, and the style files

From prompt γ-γ-γ coincidence studies with a 252Cf source, the yrast levels were identified from 2+ to 16+ and 14+ in neutron-rich 162,164Gd, respectively. Transition energies between the same spin states are higher and moments of inertia lower at every level in N = 100 164Gd than in N = 98 162Gd. These observations are in contrast to the continuous decrease in the 2+ energy to a minimum at neutron midshell (N = 104) in Er, Yb, and Hf nuclei.

Mean-field models have been quite successful in the description of bulk nuclear properties and the shell structure, so that they provide an attractive basis for the extrapolation of nuclear structure to the boundaries of the periodic system. We have investigated the performance of both Skyrmeforce and relativistic mean-field models for a larger sample of experimentally well known nuclei by comparing the predictions of various parameter sets corresponding to different versions of the models or simply distinguished by the data used for their fitting. This allows a critical evaluation of the uncertainty of extrapolation. The calculations show that while all parametrizations produce acceptable results in known nuclei, even the major magic shells predicted for the superheavy region depend on the choice of parameter set. The exact formulation and strength of the spin-orbit force appear to be the decisive factor. In addition a new formulation and parametrization of the relativistic point-coupling model with derivative and nonlinear terms is also discussed.

Recent mass measurements show a substantial weakening of the binding-energy difference δ2p(Z, N) = E(Z - 2, N) - 2E(Z, N) + E(Z + 2, N) in the neutron-deficient Pb isotopes. As δ2p is often attributed to the size of the proton magic gap, it might be speculated that reduction in δ2p is related to a weakening of the spherical Z = 82 shell. We demonstrate that the observed trend is described quantitatively by self-consistent mean-field models in terms of deformed ground states of Hg and Po isotopes.

We present a brief overview of the interplay between exotic nuclei and the development of nuclear mean field models. This is exemplified with four test cases addressing the topics of shape coexistence, isotope shifts, long isotopic chains, and superheavy elements.

In Southern Africa domesticated dogs date back to the Iron Age (circa 1430 BP). Mainly of the sight hound type, they were traditionally used for hunting. In some more pastoral societies they played...

Background: There is increasing interest in the rat model of laparoscopic surgery. This study evaluates the cardiorespiratory effects of increasing CO2 pneumoperitoneum (PP) in the rat. Methods: Nine Sprague-Dawley rats were subjected to CO2 PP at pressures of 2, 5, 10, and 15 mmHg or control (no PP) under anesthesia. Catheters were placed in the femoral artery and the jugular vein to measure heart rate (HR), blood pressure (MAP), and arterial pH, PCO2, PO2, and HCO3. A thermistor probe in the aortic arch measured cardiac output (CO) and blood temperature (BT). Results: CO2 PP had no effect on CO, MAP, or BT at any pressure. CO2 PP greater than 5 mmHg caused significant bradycardia and CO2 PP greater than 10 mmHg caused significant respiratory acidosis. Conclusions: CO2 PP pressures above 10 mmHg in rat should be avoided when performing laparoscopic surgery in the rat model.

Objective: Under experimental conditions cardiac stress may induce early immediate genes. Of these, heat shock proteins like hsp 70 have been linked to preconditioning and cellular salvage. Protooncogenes like c-fos and c-jun act as transcription factors for other genes and may be involved in the regulation of programmed cell death. Methods: Patients, 30, undergoing elective coronary artery bypass grafting, received either cold antegrade St. Thomas II or Bretschneider or Hamburg cardioplegic solutions with ten patients in each group. Tissue from right atria was removed before cardiopulmonary bypass and following cardioplegic arrest and reperfusion. Tissues were examined by Northern blots, immunohistochemistry, and in situ nick-end labeling of fragmented DNA as evidence for programmed cell death. Results: There were no significant preoperative or operative differences between groups. Following cardioplegia and reperfusion, a significant induction of both protooncogene and heat shock protein 70 mRNA was observed. Whereas levels of hsp 70 were increased about two-fold in all groups (PB 0.05), induction of c-fos and c-jun was most pronounced following the Hamburg cardioplegic solution (PB 0.05 versus baseline and for differences to other groups). Induction on the protein level was confirmed using immunohistochemistry that furthermore, identified cardiac myocytes and endothelial cells being the cell types that expressed these genes. In contrast to prebypass samples, in situ nick-end labeling of fragmented DNA following cardioplegic arrest and reperfusion was positive, preponderately in subendocardial myocytes and endothelial cells. Conclusions: Cold cardioplegia is a potent stimulus for induction of the early immediate genes examined in human hearts. Increased expression of protooncogenes may be deleterious to cardiac myocytes as indicated by in situ nick-end labeling of DNA fragments. Differences in gene induction may add additional information for the evaluation of different cardioplegic strategies. © 1997 Elsevier Science B.V.

Erich Priebke, âge de 82 ans, a ete extrade d'Argentine en Italie en 1995 afin d'y etre juge. Il est accuse du massacre de 335 hommes aux fosses adreatines en represailles de la mort de 32 soldats allemands causee par des partisans italiens. Dans cette affaire comme dans beaucoup d'autres, le criminel nazi invoque l'obeissance aux ordres pour se dedouaner. La justice italienne a autorise Erich Priebke a utiliser cet argument pour sa defense. Pour l'A., il est tout a fait inadmissible qu'un criminel de guerre nazi puisse invoquer une telle obeissance qui tend a la deresponsabilisation

Given the prevalence of medical malpractice lawsuits, physicians are often thrust into the legal world without the education of a juris doctor. The risk of facing suit varies among specialties, but there is no guarantee any physician will proceed through his or her career without being a defendant in a lawsuit. Every physician stands a significant chance of being sued. Although a lawsuit is an exhausting and intimidating situation in and of itself, the ramifications of a plaintiff's verdict could have chilling effects on the physician's life, both professionally and personally. Therefore, it is imperative that every physician have an understanding of the legal process of which he or she may become involved. This article provides a practical guide for the physician, including the fundamental procedures of a medical malpractice lawsuit, the behavior that will be expected or required of the defendant physician, and the effect of disobeying the required procedures.

Das Auffinden und das Staging von Tumoren und ihrer Metastasen in parenchymatosen Organen des Epigastriums wird durch moderne bildgebende Gerate wesentlich erleichtert. Fur Befunde, die in “kurativer” Absicht operativ entfernt werden sollen bzw. konnen wurde die Machbarkeit einer ultraschallbild-basierten Diagnostik und Therapieplanung untersucht. In 3-D Ultraschall-Bildvolumina von 20 Patienten wurden charakteristische anatomische Strukturen (z.B. Gefase, Abszesse, Tumoren) mittels spezifisch adaptierter automatischer computerbasierter Segmentierung gefunden und visualisiert. Das Auffinden pathologischer Befunde, ihre Quantifizierung und ihre raumlichen Beziehungen zu anatomischen Leitstrukturen wurden durch die 3D-Bildakquisition und die 2D- und 3D-Visualisierung wesentlich vereinfacht.

The detection and the staging of tumors and their metastases in parenchymatous organs of the epigastric organs today is improved by the enormous increase of imaging system's efficiency. For an increasing number of findings, which shall be dissected in intention to cure, the feasibility of diagnostics and therapy-planning based on sonograms was investigated. In 3-D US image volumes of approx. 20 patients, characteristic anatomical structures (e.g., vessels, abscesses, tumors) were detected by specifically adapted automatic computer-based segmentation and visualized. The detection of pathological findings, their quantification and their spatial assignment to anatomical main structures was essentially simplified by 3-D image acquisition and 2-D and 3-D visualization of segmented images.

We concentrate on the two most widely used mean-field models, Skyrme-Hartree-Fock and relativistic mean field. We discuss their performance in view of the extended range of experimental information in terms of a guided tour through selected examples of success, failures and subsequent improvement of the models drawn from comparison with key observables as isotopic shifts, trends of binding energies or single-particle spectra. Particular attention is paid to the extrapolative power with respect to superheavy elements (SHE). It turns out that the most important aspect is here the actual level sequence as implied by the given mean-field models. We will compare the performance of available parametrisations and discuss briefly possible improvements.

The diagnostic phase of an interactive research evaluation model was used in the investigation of the animal welfare needs of a low-income urban community in South Africa. Data were gathered by means of a structured interview and direct observations by animal welfare officers. During the survey of 871 animal owners in Soweto, it was found that dogs were owned by 778 households and cats by 88 households. The dog to human ratio was estimated at 1:12.4. Respondents were asked whether they enjoyed owning animals and 96.1% said that they did. Only 26.3% mentioned that they had problems with their own animals and 16.6% had problems with other people's animals. Treatment of sick animals (29.7%) was seen as a priority. However, less than 1% (n = 6) used the services of private veterinarians. Others took their animals to welfare organisations or did not have them treated. Perceptions of affordable costs of veterinary treatments were also recorded. In addition to treatment, respondents indicated a need for vaccination (22.5%), sterilisation (16.5%), control of internal (3.7%) and external (8.8%) parasites, education and extension (6.6%), prevention of cruelty to animals (3.2%) and expansion of veterinary clinics to other parts of Soweto (1.3%).

A large thrombus was found at the ileal bifurcation on post mortem examination of a 6-year-old Jersey cow which presented clinically with a history of acute onset recumbency, hind limb paresis and skin necrosis over the sacral area. Other significant findings on post mortem were traumatic reticuloperitonitis accompanied by mural thrombosis of the left ventricle associated with a purulent sinus tract through the ventricular wall, fibrous adhesions between the pericardium, diaphragm and liver, and multiple infarcts in both kidneys.

Two outbreaks of neurotoxicoses are reported in cattle browsing on the leaves of Ficus spp. In the first outbreak, three animals died and one became ill. A sheep developed severe nervous signs, including tetanic spasms, when dosed with the leaves of Ficus ingens var. ingens from the toxic camp where the cattle had died. The second outbreak resulted in the death of 12 heifers within 48 h of ingestion of the leaves of F. cordata subsp. salicifolia. Clinical signs included hyperaesthesia, ataxia, muscle tremors and padding motions while in lateral recumbency. Similar signs were reproduced by drenching the incriminated leaves to a steer. The sheep dosed with F. ingens var. ingens and two cattle, one of which had died during the second outbreak and the steer drenched with F. cordata subsp. salicifolia, were necropsied. Light microscopical examination consistently revealed oedema of the central nervous system. In the steer, focal demyelination was evident in localized areas of the brain and spinal cord. Liver lesions ranged from mild degeneration to focal disseminated necrosis of hepatocytes.

Objective: To determine how soon after trauma pulmonary embolism (PE) occurs and if there is an association between the duration of this interval and mortality. Design: Retrospective case series. Patients: All patients admitted to our trauma service with established PE based on high probability findings on ventilation perfusion scan, positive results on a pulmonary arteriogram, or autopsy from July 1, 1990, to September 30, 1995. Main Outcome Measure: Time interval between injury and PE. Setting: Level I university trauma center. Results: Of 18 255 trauma patients identified, 63 met our criteria for PE (30 using a pulmonary arteriogram; 26, a ventilation perfusion scan; and 7, autopsy). Four patients (6%) had a documented PE on day 1 following injury. Mortality was not correlated with the interval between injury and PE. Of the 63 patients, 58 (92%) had 1 or more established risk factors for thromboembolism. The ratio of PaO 2 to fraction of inspired oxygen was the only factor predictive of mortality ( P =.02, logistic regression analysis). Conclusions: Pulmonary embolism occurs in the immediate period following injury. Aggressive workup in patients with signs consistent with PE should be instituted promptly. Trauma patients who have at least 1 risk factor for thromboembolism should receive prophylaxis as soon after injury as possible. Arch Surg. 1997;132:862-867

Recent research in job classification has focused on the appropriate data analysis model for analyzing the similarities and differences among jobs. In the present research, the data analysis model is held constant, and the type of job analysis data is varied to examine the effect on the resulting job classification decisions. Seven foremen jobs in a chemical processing plant were analyzed using three different levels of job analysis data: task-oriented, worker-oriented, and abilities-oriented. All three sets of data were analyzed using the same hierarchical clustering procedure. Results indicated that the number and type of resulting job clusters was clearly dictated by the type of job analysis data that was used to compare the foremen jobs. Practical implications of these findings are presented.

This paper compares two job classification methods for showing the appropriateness of cognitive tests in settings that were not involved in supplying data for a validity generalization analysis. One approach was an elaborate quantitative procedure that involved a lengthy job inventory and a multivariate item analysis. This approach was shown to be highly successful when applied to the responses from 1179 job inventories collected in 54 petroleum-petrochemical plants from 30 different companies. The other procedure involved simple job classification judgments by supervisors and incumbents. This latter approach was shown to be as effective, but was much less time consuming and costly. Professional and legal implications of these findings are discussed.

The purpose of this study was to determine the extent to which direct judgments of similarity by supervisors and incumbents could provide the same job classification results as a more elaborate job analysis procedure involving measures of task overlap among jobs. To accomplish this, 8 foreman jobs in a chemical processing plant were analyzed and compared on 237 task statements. In addition, 15 foremen incumbents and 17 supervisors evaluated the similarities among the same 8 foremen jobs in a paired comparisons rating task. The task-oriented job analysis required hundreds of man-hours to complete; the rating task took 15 minutes. Results using hierarchical cluster analysis and multidimensional scaling analysis revealed that the global judgments and the task-oriented data led to identical conclusions. Also, it was found that incumbent ratings produced the same results as ratings from supervisors. Uses, advantages, and disadvantages of the procedure are outlined.

This paper illustrates a methodological approach to classifying jobs for the purpose of developing performance evaluation instruments. The approach was to administer a worker-oriented job inventory to 2,023 incumbents across several jobs and several levels of responsibility (rank) in the U. S. Coast Guard. The data from the job inventory were then analyzed using Tucker's Three-Mode Factor Analysis. Output from the three-mode factor analysis was used to identify combinations of jobs and ranks for which separate appraisal instruments could be developed. In addition, output from the three-mode factor analysis was used to suggest the content of the various appraisal instruments. Advantages, applications, and limitations of this approach are discussed.

Previous research (Smith & Hakel, 1979) raised the possibility that the Position Analysis Questionnaire (PAQ) only captures common knowledge, or stereotypes, about jobs, Cornelius, DeNisi, and Blencoe (1984) presented data to refute this, but found that the number of PAQ items rated docs not apply (DNA) was related to the agreement between naive raters and expert raters. The present study used data from 87 analysts and 24 jobs. Naive ratings were those obtained from analysts who had not studied the job, whereas expert ratings were those obtained from raters who had observed the job, interviewed incumbents, and written task statements describing the job. These ratings were then compared to target-score profiles obtained from PAQ services. Results confirmed earlier hypotheses that large numbers of DNA items artifactually inflate correlational estimates of agreement between expert and naive raters. In addition to this artifact, results also supported the view that the PAQ is less appropriate as a job analysis tool for some types of jobs. Implications for research and practice are discussed. Recently, questions have been raised about the validity of ratings obtained on structured job analysis instruments. The validity of these ratings has generally been taken for granted; however, given the range of applications for these ratings, these questions represent potentially serious problems for human resource practitioners and researchers. Most of the attention in this area has focused on the Position Analysis Questionnaire (PAQ; McCormick, Jeanneret, & Mecham, 1972). The PAQ is the most frequently used job analysis instrument in the published literature (Cornelius, 1987), and so it follows that there should be a great deal of concern about the validity of the data generated by the PAQ. Furthermore, PAQ ratings have been used in a variety of applications, such as those concerned with establishing wage and salary levels for jobs (Robinson, Wahlstrom, & Mecham, 1974), identifying aptitude tests that can be used as valid selection devices (McCormick, DeNisi, & Shaw, 1977), and establishing job classification systems (Taylor, 1978).

This study compared three judgment strategies used to determine composite performance ratings, based on information varied along three, six or nine dimensions, in a factorial design. College students (N = 270) rated written descriptions of the performance of hypothetical college instructors, using numerical rating scales and salary increase estimates. The entire procedure was repeated on two occasions. The three judgment strategies were compared in terms of intrarater reliability across occassions, intrarater convergence across rating methods, and interrater agreement, using both correlations and mean absolute deviations as dependent measures. The results based on mean absolute deviations supported the predicted overall superiority of the decomposed judgment strategy with combination by algorithm. The results based on correlations indicated that a simple holistic strategy was as effective as the decomposed judgement approach. Both sets of results indicated that a decomposed judgment strategy with combination by algorithm. The results based on correlations indicated that a simple holistic strategy was as effective as the decomposed judgment approach. Both sets of results indicated that a decomposed judgment strategy followed by a clinical overall evaluation is a particularly ineffective method for making performance evaluations. This finding has important implications since the decomposed—clinical strategy is similar to the approach often used in actual performance rating situations.

A finding by Smith and Hakel (1979) is that job expert ratings on the PAQ correlate highly with ratings obtained from college students who are given no information about jobs other than their titles. One possible explanation for this finding is that the PAQ measures only trivial or common knowledge about work that both experts and naive observers possess. This particular view, of course, has serious implications for the use of the PAQ. In this paper we point out a problem in the way Smith and Hakel calculated the convergent validity between expert raters and naive raters. We also present the results from a replication study that indicate convergent validities are much lower than those reported by Smith and Hakel. Additional points are presented in order to caution against the interpretation that the PAQ measures only common knowledge about jobs.

Although worker-oriented job inventories such as the Position Analysis Questionnaire (PAQ) have become very popular, the high level of verbal ability they require limits the range of situations in which they may be applied. In an effort to make the worker-oriented approach more widely applicable, Cornelius and Hakel (1978) developed the Job Element Inventory (JEI), a structured questionnaire modeled after the PAQ but with a much lower reading level. Using the approach followed when deriving the PAQ's dimensionality, we examined the factor structure of the JEI. In Study 1 we reported the results of factor and policy-capturing analyses of JEI data from 2,029 U.S. Coast Guard incumbents, and in Study 2 we reported quantitative comparisons between the JEI and PAQ factors on a sample of 85 municipal government positions. Our results indicate that JEI factors closely parallel those of the PAQ.

A Monte Carlo study was carried out to investigate the ability of ALSCAL to recover true structure inherent in simulated proximity measures. The nature of the simulated data varied according to (a) number of stimuli, (b) number of individuals, (c) number of dimensions, and (d) level of random error. Four aspects of recovery were studied: (a) SSTRESS, (b) recovery of true distances, (c) recovery of stimulus dimensions, and (d) recovery of individual weights. Results indicated that all four measures were rather strongly affected by random error. Also, SSTRESS improved with fewer stimuli in more dimensions, but the other three indices behaved in the opposite fashion. Most importantly, it was found that the number of individuals, over the range studied, did not have a substantial effect on any of the four measures of recovery. Practical implications and suggestions for further research are discussed.