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Notizen: Purpose This study measured the effects of commercial resin type on maxillary complete dentures with monoplane teeth by periodically comparing the occlusal vertical dimension of the polymerized dentures with the baseline, wax trial denture fiducial measurements.Materials and Methods Commercially available compression-molded, injection-molded, and fluid poly(methyl methacrylate) resins, as well as one compression-molded methyl acrylate ester copolymer, were evaluated. Ten dentures were fabricated from each resin using monoplane teeth. The occlusal vertical dimension at the articulator pin was measured at the wax denture stage for each specimen, and changes in occlusal vertical dimension for each denture were evaluated at a simulated laboratory remount, and at 0, 3, 6, 24, and 48 hours after a simulated clinical remount. Repeated measures analysis of variance (α= 0.05) and post hoc one-way factorial analysis of variance and Scheffe's F-Tests for each resin group were performed using ranks of raw data.Results Changes in the maxillary denture mean occlusal vertical dimensions were recognized throughout the evaluation periods compared with the wax-denture baseline, and time was a significant influence on displacement (p= .0001). Only the compression-molded poly(methyl methacrylate) dentures exhibited a mean laboratory remount occlusal vertical dimension that was significantly greater than the mean wax denture measurement, and all resin systems exhibited occlusal error that was significantly less than the laboratory remount measurements at 48 hours. At 48 hours, all resin groups exhibited mean occlusal vertical dimension changes that were less than 1 mm compared with the wax denture. Only compression-molded poly(methyl methacrylate) dentures exhibited a mean 48-hour clinical remount measurement that was statistically similar to the mean wax denture occlusal vertical dimension.Conclusions Individual maxillary dentures from all resin types and at all intervals exhibited dimensional change. At the last evaluation period, the compression-molded poly(methyl methacrylate) showed no change in mean occlusal vertical dimension from baseline, whereas remaining groups exhibited occlusal vertical dimensions significantly less than baseline.

Notizen: It is difficult to predict accurately the ultimate effectiveness of a preservative in any but the simplest cosmetic or pharmaceutical formulation. It is thus necessary to obtain some assurance of its likely in-use performance in a formulated product. A challenge test is a procedure in which a product is challenged by exposure to specified types of bacteria and fungi to determine whether it is adequately preserved. Assessment of preservative efficacy is needed over the intended shelf-life of that product. Test organisms should be representative of those likely to occur as contaminants during use and should consist of Gram-positive and Gram-negative bacteria, mould and yeast. In-house factory isolates obtained as a result of contamination of earlier batches of a product may also be included. The organisms, as single or mixed inocula, are inoculated (usually as a single challenge, although some advocate multiple challenges) into samples of the product and aliquots removed at appropriate intervals for the determination of survivors. Interpretation of data is normally based on pharmacopoeial or other official protocols. Challenge testing should be undertaken at the beginning, during and at the end of the shelf-life of the product. An alternative, the D-value, approach is open to criticism and further studies are required that utilize rapid methods, e.g. impedance, for the detection of survivors before these can be considered to be a suitable replacement for the more traditional but very time-consuming, viable counting procedures.

Notizen: I commend Milich and colleagues for their well-reasoned position that the predominantly inattentive type (PIT) of ADHD is a distinct disorder, not a subtype of ADHD. Several issues pertain to future research. Among these are the need to recognize that attention is multidimensional such that several distinct disorders of attention are likely to be identified besides ADHD, one now being PIT. Of great immediacy is the need to expand and refine the symptom list that best distinguishes this disorder from others and to pursue neuropsychological studies using double-dissociation methods that can elaborate the unique psychological domains affected by PIT. In doing so, it will be critical to identify the domains of impairment adversely affected by PIT.

Notizen: Annual screenings of preschool children at kindergarten registration identified 158 children having high levels of aggressive, hyperactive, impulsive, and inattentive behavior. These “disruptive” children were randomly assigned to four treatment conditions lasting the kindergarten school year: no treatment, parent training only, full-day treatment classroom only, and the combination of parent training with the classroom treatment. Results showed that parent training produced no significant treatment effects, probably owing largely to poor attendance. The classroom treatment produced improvement in multiple domains: parent ratings of adaptive behavior, teacher ratings of attention, aggression, self-control, and social skills, as well as direct observations of externalizing behavior in the classroom. Neither treatment improved academic achievement skills or parent ratings of home behavior problems, nor were effects evident on any lab measures of attention, impulse control, or mother-child interactions. It is concluded that when parent training is offered at school registration to parents of disruptive children identified through a brief school registration screening, it may not be a useful approach to treating the home and community behavioral problems of such children. The kindergarten classroom intervention was far more effective in reducing the perceived behavioral problems and impaired social skills of these children. Even so, most treatment effects were specific to the school environment and did not affect achievement skills. These findings must be viewed as tentative until follow-up evaluations can be done to determine the long-term outcomes of these interventions.

Notizen: Resistance to pea seed-borne mosaic virus (PSbMV) pathotype P-1 in peas is conferred by sbm1 with recessive inheritance. PSbMV is an economically important pathogen with world-wide distribution that causes significant losses in pea yield and reduces seed and produce quality. The sbm1 gene was previously mapped to linkage group VI on molecular linkage maps of the pea genome. To improve plant breeders’ ability to develop varieties resistant to PSbMV, two random amplified polymorphic DNA markers (G05_2537 and L01_910) and one restriction fragment length polymorphism (P446) linked to sbm1 have been identified. The genomic sequences for these markers have been characterized and the information used to develop three simple polymerase chain reaction-based STS (sequence tagged site) assays. Linkage analysis in two F2 populations showed that the most tightly linked of these three STS loci (sG05_2537) is approximately 4 cM from sbm1. Characterization of a collection of resistant and susceptible germplasm demonstrated a strong correlation between STS alleles and sbm1 alleles, indicating the utility of these markers for marker-assisted selection in breeding programmes using a range of germplasm sources.

Notizen: We recorded a series of 34 fin whale vocalizations using four calibrated hydrophones in a towed array. The whale's location was determined using arrival-time differences of each call at the hydrophones. The recordings showed evidence of interference between signals propagating along direct and surface-reflected paths (the “Lloyd Mirror”). We made preliminary estimates of source level (SL) using a spherical spreading model of transmission loss. We then applied a conservative correction for the effect of interference by subtracting the maximum possible signal enhancement from the preliminary SL estimate. These adjusted spherical spreading estimates had a median of 171 dB re 1 μPa at 1 m, with a range of 159–184 dB. These are the first SL estimates that explicitly attempt to correct for possible interference effects. We also propose a method that simultaneously estimates SL and source depth by fitting a Lloyd Mirror transmission loss curve to the measured received level, known receiver depth, and source-to-receiver range. Attempts to apply this method to the present data set yielded inconsistent results, probably because of the small number of hydrophones available. With more hydrophones in the interference field, this new method should produce reliable estimates of SL and depth of vocalizing whales.

Notizen: From October 1996 through September 1998, we used bottom-mounted hydrophone arrays to monitor deep-water areas north and west of the British Isles for songs of humpback whales (Megaptera novaeangliae). Singing humpbacks were consistently detected between October and March from the Shetland-Faroe Islands south to waters west of the English Channel. Temporal and geographic patterns of song detections, and movements of individually tracked whales, exhibited a southwesterly trend over this period, but with no corresponding northward trend between April and September. These results, together with a review of historical data from this area, suggest that the offshore waters of the British Isles represent a migration corridor for humpbacks, at least some of which summer in Norwegian (and possibly eastern Icelandic) waters. The migratory destination of the detected animals remains unknown, but the limited data suggest that these whales are bound primarily for the West Indies rather than historical breeding areas off the northwestern coast of Africa. Humpbacks detected in British waters after early to mid-March probably do not undertake a full migration to the tropics. These data provide further evidence that singing is not confined to tropical waters in winter, but occurs commonly on migration even in high latitudes.

Notizen: Melanocytic nevi in certain locations such as the genital and acral sites may have atypical histologic features simulating melanoma. We studied the microscopic findings of 40 melanocytic nevi of flexural sites (axilla, umbilicus, inguinal creases, pubis, scrotum and perianal area) to verify if flexural nevi show distinctive features similar to melanocytic nevi of the genital skin. The patients were young (mean age 20 years), the lesions were mostly removed for cosmetic reasons and we are not aware of any deaths or complications related to the removed nevi. We found that 22 (55.5%) out of 40 flexural nevi had “a nested and dyshesive pattern” similar to the melanocytic nevi of genital skin. This pattern was characterized by the confluence of enlarged nests with variation in size, shape and position at the dermo-epidermal junction and by the diminished cohesion of melanocytes. Dermatopathologists should pay attention to the “nested and dyshesive pattern” of flexural nevi that may mimick hystologic changes of melanoma.

Notizen: Objectives: To undertake a blind caries and fluorosis prevalence study of Grade 1 (aged 5/6 yr) and Grade 4–7 (aged 8–12 yr) children from naturally water-fluoridated (1 ppm, since 1985) Burghead, Findhorn & Kinloss (F), and nearby nonfluoridated Buckie & Portessie (N-F), in rural Morayshire, Scotland.Methods:  A blind clinical (+ 10% repeats) caries study of the above townships' 5/6-yr-old lifetime (15 F; 43 N-F), and 8–12-yr-old lifetime (55 F; 136 N-F)/school-lifetime (31 F; 37 N-F) residents was undertaken following bussing of these children to a common examination site in close-by Elgin Town Hall. Initially, each child was asked about their own perception of the aesthetics of their maxillary front teeth. Fluorosis was assessed clinically using the TF Index, as well as photographically − for later blind scoring (+ 10% repeats for lifetime 8–12-yr-olds) of slides by four dental and two lay ‘jurors’, alongside a now-established UK ‘bench-mark’ mildly mottled (TFI = 2), fluorosis comparator slide, judged in previous studies to be aesthetically lay-acceptable. In addition, by parental questionnaire, information was sought concerning their child's fluoride supplement and dentifrice usage histories. Results: For 5/6-yr-olds, mean primary caries scores were 96.0% less in fluoridated than nonfluoridated subjects (P 〈 0.01). In 8–12-yr-olds, DMFT values favoured water-fluoridated subjects; their caries-free trend was significant (P 〈 0.001 overall). Clinically, 33% of all lifetime F subjects and 18% of all N-F pupils had fluorosed maxillary anterior teeth (P = 0.045), but no statistically significant difference was found between the 7% F and 3% N-F subjects with TFI scores 〉 2 (P = 0.25). Photographically, ‘jury’ mottling assessment (+ 10% repeats) of projected slides resulted in at least 1 : 6 positive scores in 43.6% of F and 30.9% of N-F pupils, albeit they unanimously scored only nine F and five N-F children as having fluorosed teeth (P 〈 0.01). In no case did all members score TFI 〉 2. Dental and lay scorers rated TFI = ½ in only a further 9.1% and 5.5% of F subjects, respectively, compared to 0.7% and 1.5% respectively of N-F pupils. Again, TFI 〉 2 was scored unanimously in no child. No differences were found regarding the children's own degree of anterior tooth aesthetic nonacceptability between F (11%) and N-F (12%) prevalence (P = 0.75). Finally, only one F child had taken F supplements and, while 26 N-F had used F drops, no significant relationship was found between their usage and TFI values in the latter group (P = 0.49). Additionally, no relationship was noted between clinical TFI scores and the age at which parents stated fluoridated dentifrice toothbrushing commenced, between 0 and 24 + months of age. Conclusions: Considerable caries benefit has accrued to those Morayshire rural children who have received naturally fluoridated water (at 1 ppm) throughout their lives, as compared to their socioeconomically similar, nonfluoridated rural counterparts. Furthermore, in spite of all but two subjects claiming to have brushed regularly with fluoridated dentifrice (and no evidence of the availability of nonfluoridated toothpaste being purchasable in the five townships), only borderline mild fluorosis disadvantages have been noted clinically, and none by the subjects' own aesthetic perceptions. Finally, no evidence was found to suggest any delay in permanent tooth eruption patterns of the F subjects. It would seem appropriate therefore, that adjustment of Scots' drinking waters' natural fluoride levels to 1 ppm should be pursued to extend similar dental advantages to the vast majority of that population (both young and old) which, it is well documented, has the worst dental health of mainland UK.

Notizen: The purpose of the present research is to develop a reliable and valid scale to distinguish and measure the three environmental factors of dynamic structural framework, control of workplace decisions, and fluidity in information sharing that are conceptually related to and affect an employee's perception of empowerment. By quantifying the environmental factors that facilitate empowerment through a valid and reliable scale human resource departments will be provided with information that will suggest environmental changes they can implement to improve perceptions of empowerment on the part of employees. Strengths and weaknesses of the scale developed, the organizational empowerment scale, are also discussed.