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The embryogenesis and morphologic characteristics of the teeth and supporting structures of the Mongolian gerbil were studied in animals ranging in age from ten days to five years. Three molar teeth are present in each quadrant and consist of three, two, and one lobe respectively. The occlusal surfaces are flat and devoid of enamel. The lobular nature of the teeth effects a series of buccal and lingual grooves extending almost the entire height of the crown. On the buccal and lingual prominences of the crown lobes and on the interproximal surface, the enamel is covered by a thin layer of cementum which runs one-sixth up the height of the tooth. Within the grooves, a thick covering of globular-like cementum, which is continuous with the root covering, can be seen. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate nurses' trust in their leader and organizational commitment, examining the relationship between these factors postpandemic and investigating if age, tenure, and specialty area predicted trust and commitment., Background: The nursing shortage was intensified by COVID-19. Nonnursing studies have explored the relationship of employee trust with organizational commitment, illustrating sparsity in nursing literature., Methods: This study used a cross-sectional, descriptive, correlational design. An electronic survey was sent to more than 1000 nurses, with a final sample size of 135 over 6 weeks., Results: Results demonstrated high levels of both trust and commitment. The correlation coefficients of all study variables were significant (P < 0.001). Organizational tenure predicted employee trust., Conclusions: Developing leadership skills in building trust with the nursing team contributes to increased organizational commitment. Interventions such as leader development in establishing trust and building relationships with their team members may improve nurse retention and organizational commitment., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

When applying electron or gamma irradiation to poly-3-hydroxybutyrate (P3HB), main chain scissions are the dominant material reactions. Though propositions have been made that crosslinking in the amorphous phase of P3HB occurs under irradiation, a conclusive method to achieve controlled additive free irradiation crosslinking has not been shown and no mechanism has been derived to the best of our knowledge. By applying irradiation in a molten state at 195 °C and doses above 200 kGy, we were able to initiate crosslink reactions and achieved gel formation of up to 16%. The gel dose D gel was determined to be 200 kGy and a range of the G values, the number of scissions and crosslinks for 100 eV energy deposition, is given. Rheology measurements, as well as size exclusion chromatography (SEC), showed indications for branching at doses from 100 to 250 kGy. Thermal analysis showed the development of a bimodal peak with a decrease in the peak melt temperature and an increase in peak width. In combination with an increase in the thermal degradation temperature for a dose of 200 kGy compared to 100 kGy, thermal analysis also showed phenomena attributed to branching and crosslinking.

Bio-based polyamide 10.10 (PA 10.10) has excellent properties compared to other bio-based polymers such as polylactic acid (PLA) or polyhydroxyalkanoates (PHAs) and is therefore used in more technical applications where higher strength is required. For foam and filament extrusion, a good balance between strength and stiffness of the polymer is needed. Therefore, two commercial chain-extenders (Joncryl ® ADR types) with different epoxy functionalities are used to modify the melt properties of PA 10.10. The chain-extenders are used in a concentration range up to 1.25 wt.%. The range of glass transition temperature widens with increasing Joncryl ® content, and the apparent activation energy shows a maximum at a concentration of 0.5 wt.%. Furthermore, the melting temperatures are constant and the crystallinity decreases with increasing chain-extender content due to the formation of branches. During the second heating run, a bimodal melting peak appeared, consisting of α-triclinic and pseudo γ-hexagonal crystals. The weight average molar masses ( M w ) measured by gel permeation chromatography (GPC) increased linearly with increasing ADR 4400 content. In contrast, the compounds containing ADR 4468 show a maximum at 0.5 wt.% and it begins to decrease thereafter. The rheological data show an increase in viscosity with increasing chain-extender content due to branch formation. ATR spectra of the compounds show a decrease at the wavelength of the primary (3301 cm -1 ) and secondary (1634 cm -1 ) (-NH stretching in PA 10.10) amine, indicating that chain-extension, e.g., branching, takes place during compounding.

Fermented polymers like biobased poly( butylene succinate ) (BioPBS) have become more relevant as technical substitutes for ductile petrochemical-based polymers but require biogenic functional additives to deaccelerate undesired thermo-oxidative degradation and keep a fully biobased character. In this paper, the influence of coffee parchment (PMT) from two different varieties and processings on the thermo-oxidative stabilization and mechanical properties of poly( butylene succinate ) composites up to 20 wt.-% PMT were investigated. Micronized with a TurboRotor mill, both PMT powders differ in particle size and shape, moisture ab- and adsorption behavior and antioxidative properties. It could be shown that pulped-natural PMT consists partially of coffee cherry residues, which leads to a higher total polyphenol content and water activity. The homogeneous PMT from fully washed processing has a higher thermal degradation resistance but consists of fibers with larger diameters. Compounded with the BioPBS and subsequent injection molded, the fully washed PMT leads to higher stiffness and equal tensile strength but lower toughness compared to the pulped-natural PMT, especially at lower deformation speed. Surprisingly, the fully washed PMT showed a higher stability against thermo-oxidative decomposition despite the lower values in the total phenol content and antioxidative activity. The required antioxidative stabilizers might be extracted at higher temperatures from the PMT fibers, making it a suitable biogenic stabilizer for extrusion processes.

Biobased poly(butylene succinate) (PBS) represents one promising sustainable alternative to petroleum-based polymers. Its sensitivity to thermo-oxidative degradation is one reason for its limited application. In this research, two different varieties of wine grape pomaces (WPs) were investigated as fully biobased stabilizers. WPs were prepared via simultaneous drying and grinding to be used as bio-additives or functional fillers at higher filling rates. The by-products were characterized in terms of composition and relative moisture, in addition to particle size distribution analysis, TGA, and assays to determine the total phenolic content and the antioxidant activity. Biobased PBS was processed with a twin-screw compounder with WP contents up to 20 wt.-%. The thermal and mechanical properties of the compounds were investigated with DSC, TGA, and tensile tests using injection-molded specimens. The thermo-oxidative stability was determined using dynamic OIT and oxidative TGA measurements. While the characteristic thermal properties of the materials remained almost unchanged, the mechanical properties were altered within expected ranges. The analysis of the thermo-oxidative stability revealed WP as an efficient stabilizer for biobased PBS. This research shows that WP, as a low-cost and biobased stabilizer, improves the thermo-oxidative stability of biobased PBS while maintaining its key properties for processing and technical applications.

Increasing interest in bio-based polymers and fibers has led to the development of several alternatives to conventional plastics and fibers made of these materials. Biopolymer fibers can be made from renewable, environmentally friendly resources and can be fully biodegradable. Biogenic resources with a high content of carbohydrates such as starch-containing plants have huge potentials to substitute conventional synthetic plastics in a number of applications. Much literature is available on the production and modification of starch-based fibers and blends of starch with other polymers. Chemistry and structure-property relationships of starch show that it can be used as an attractive source of raw material which can be exploited for conversion into a number of high-value bio-based products. In this review, possible spinning techniques for the development of virgin starch or starch/polymer blend fibers and their products are discussed. Beneficiation of starch for the development of bio-based fibers can result in the sustainable replacement of oil-based high-value materials with cost-effective, environmentally friendly, and abundant products.

Hypertension is a major risk factor for cerebral and coronary disease and its early detection is very important for the family physician. We checked the implications of a hypertension survey in the community (from the age of 10 years) on the attitude of the primary care team. We found that although the medical team was aware of the significance of early detection and treatment of hypertension, according to the "law of halves" half the hypertensives were in treatment and of them half had normal blood pressure. This fact is probably not related to the quality of medical care. High risk groups identified were hypertensive patients who smoked, Jewish men of western origin, and Jewish women of Asian-African origin (who had a high rate of strokes). These groups were targeted for active intervention by the primary care team. This survey is part of planned community-intervention by the primary care team in the field of hypertension.

Physicians in general are at risk for the development of stress, drug and alcohol abuse, as well as for suicide. Furthermore, the treatment of the sick physician is more difficult than that of a 'regular' patient. These difficulties may cause the postponement of diagnosis and treatment to critical stages of the disease. This paper presents a study of self-rated health and health-seeking behaviour of Israeli family physicians and their families. Our major finding is that two-thirds of the physicians do not have a regular family physician, and physicians who suffer from chronic diseases are even less likely to be treated than the 'healthy' ones. Twenty eight per cent of the physicians did not use any kind of medical consultation. However, each physician's family did receive some form of medical consultation, although in some cases this was not the usual form of medical care. The physicians who treated themselves tended to treat their own families and vice versa. Eighty-eight per cent of the physicians reported stress owing to their work (work overload, poor relationships with the medical team or with the patients), and 20% said that their work as physicians negatively affected their marital life. The relationship between the help-seeking behaviour of the family physician and the quality of care they give is as yet unclear. Various alternatives are raised for changing family physicians' behaviour as well as the primary care health system in order to possibly provide better care for the physicians and their families.

As part of an ongoing quality-control program, a retrospective survey of all rigid rectoscopies performed by a family physician as a diagnostic procedure in 1985-1986 was undertaken. 35 men and 27 women were examined after an average wait of 2.5 days. Most were referred because of rectal bleeding. 3 malignant and 4 benign rectal tumors were diagnosed. In cases with no pathological finding, a subsequent barium enema and/or colonoscopy resulted in the diagnosis of 2 more proximal cancers. This frequency of tumors is relatively high compared with other series, in which there had not been systematic screening for early detection of colonic cancer. There were no complications of the rectoscopies. This survey strengthens our impression that rectoscopy can be carried out effectively by the family physician in the clinic.