46 research outputs found

    Limits to reproduction and seed size-number trade-offs that shape forest dominance and future recovery

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    International audienceThe relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundation for assessing fitness in forest trees. Four major findings emerged. First, seed production is not constrained by a strict trade-off between seed size and numbers. Instead, seed numbers vary over ten orders of magnitude, with species that invest in large seeds producing more seeds than expected from the 1:1 trade-off. Second, gymnosperms have lower seed production than angiosperms, potentially due to their extra investments in protective woody cones. Third, nutrient-demanding species, indicated by high foliar phosphorus concentrations, have low seed production. Finally, sensitivity of individual species to soil fertility varies widely, limiting the response of community seed production to fertility gradients. In combination, these findings can inform models of forest response that need to incorporate reproductive potential

    Relationship with peers of young school-aged children with type 1 diabetes

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    Background: Functioning in a peer group plays an important role in child development. Building self-esteem of children depends on many factors such as physical health, self-evaluation of their physical performance, academic achievement, social support, family relationships, as well as relationships with peers and teachers. Importance of contacts with peers increases during school-age. At this time children are not able to reject the opinion of other people and subject their behaviour completely to the expectations of their peers. When the need for emotional contact is not satisfied, the complex of being different appears. Isolation within group causes a sense of inferiority, the child becomes passive and resigned. Children, who are chronically ill, rejected or isolated often follow negative emotions in their actions, they become aggressive towards other children or do not want to continue learning. Often the decision about an individual teaching plan results in further isolation of the child. The child’s position in the peer group affects the developing personality, self-confidence and self-esteem. Aim of the study: The aim of the study was to determine the interpersonal relationships of young school-aged children with type 1 diabetes in their peer groups. Material and methods: The study was conducted on children with type 1 diabetes and their parents, who are supervised by Clinic of Diabetes, Regional Medical Center in Opole. The research tool used in both groups was a questionnaire consisting of open and closed questions elaborated by the authors of this study. Results: 73% (41) of evaluated children declared that diabetes does not hinder their performance at school. 93% (55) children claimed that they do not hide their condition from their peers. In addition, 61% (34) talk about their illness with their peers and 69% (38) of them can count on their peers’ help in self-control of diabetes. 71.9% (46) of parents of children with type 1 diabetes allow their children to participate in school trips and 68.8% (44) to participate in school competitions. Conclusions: In most children, diabetes does not affect children’s performance at school. They participate in classes, are accepted and liked in their peer group. Chronically ill children should be able to participate in all types of activities as much as their healthy peers. It seems necessary to continue studies on performance of young school-aged children with type 1 diabetes in their peer group

    Photodynamic therapy (PDT) in dermatology - what's new?

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    Poniższa praca prezentuje przegląd piśmiennictwa dotyczącego wskazań do leczenia fotodynamicznego w chorobach nowotworowych skóry, jak i prace prezentujące nowe możliwości zastosowania PDT także w nienowotworowych chorobach skóry. Udowodnione jest skuteczne leczenie z zastosowaniem terapii fotodynamicznej takich schorzeń, jak raki podstawnokomórkowe, choroba Bowena, rogowacenie słoneczne, powierzchowny rak kolczystokomórkowy, przerzuty raka piersi do skóry, ziarniniak grzybiasty oraz łuszczyca. Wykazano także, iż PDT z miejscową aplikacją kwasu 5-delta-aminolewulinowego (ALA) jest skuteczne w leczeniu epidermodysplazji brodawczakowatej, chorobie Dariera oraz w schorzeniach mikrobiologicznych, np. w kandidiazie. Nowym kierunkiem rozwoju PDT są wskazania kosmetyczne (odmładzanie skóry światłem). Wszystkie te wskazania związane są z selektywnym, bezpiecznym i skutecznym działaniem terapii fotodynamicznej.The study presents main medical indications of photodynamic therapy in skin neoplasm and new directions in the other, nonmalignant skin diseases. In dermatology PDT has been proven to be effective in the treatment of basal cell carcinomas (BCC), Bowen's disease, actinic keratoses, superficial squamous cell carcinomas (SCC), metastatic breast cancer, mycosis fungoides and psoriasis. It was also demonstrated that PDT with topical application of d-aminolevulinic acid (ALA) can selectively photosensitize other skin lesions, i.e.: epidermodysplasia verruciformis and affected skin areas in Darier's disease and microbiological infections (candidiasis). New approach of PDT is connected with cosmetic indication- photo-rejuvenation. These whole indications are connected with selective, safety and effective properties of PDT

    Inhibition of cross-bridge binding to actin by caldesmon fragments in skinned skeletal muscle fibers.

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    Several regions within the 35-kDa COOH-terminal portion of caldesmon have been implicated in the ability of caldesmon to inhibit actin-activated myosin ATPase activity. To further define the functional regions of caldesmon, we have studied the effects of three chymotryptic fragments, one fragment produced by CNBr digestion and two fragments produced by digestion with submaxillaris arginase C protease, on the relaxed stiffness and active force of rabbit psoas fibers. Each of the regions of caldesmon studied had either direct or indirect effects on single-fiber mechanics. The 35-kDa and 20-kDa fragments of caldesmon, like intact caldesmon, were effective inhibitors of fiber stiffness, a measure of cross-bridge attachment. The 7.3-kDa and 10-kDa fragments, which constitute the NH2 and COOH halves of the 20-kDa fragment, inhibited both relaxed fiber stiffness and active force production, but with a reduced efficacy compared to the 20-kDa fragment. These results suggest that several regions within the 35-kDa COOH-terminal region of caldesmon are required for optimum function of caldesmon and that function includes inhibition of weak cross-bridge attachment and force production

    Venous air embolismdue to vaginal injuries through sexual intercourse. Critical analysis and review of the literature on frequency and diagnostics

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    BackgroundIn acriminal trial in Germany in 2013, amedical expert nominated by the defence stated in the appeal trial the controversially discussed opinion that awoman had died from an air embolism due to vaginal intercourse with exclusively penile penetration and injury to the vaginal wall. This diagnosis had been established by the expert based on histological examination of the lungs and vaginal injuries years after the womans death.ObjectiveThe frequency of the diagnosis air embolism as a result of vaginal injuries due to intravaginal intercourse and the modality of the diagnosis were reviewed.Material and methodsAselective literature review was performed. Furthermore, questionnaires were sent to all forensic medical institutes and to directors and chief physicians of gynecological clinics of large cities in Germany.ResultsIn the literature two case reports could be found, which by critical analysis showed significant errors in the diagnosis according to the state of science at the time of publication. In over 300,000 autopsies performed between 1990 and 2016, the 26forensic medical institutes in Germany, which had answered the questionnaire, had never diagnosed air embolism as a result of vaginal injuries due to intravaginal intercourse. All 32professionally experienced gynecologists who responded to the questionnaire had never in their career treated survived or fatal cases of air embolism after vaginal injuries through sexual intercourse or had knowledge of them.ConclusionAccording to the survey and critical analysis of the very few published case reports, there is no evidence for adiagnosis of the cause of death as air embolism after vaginal injuries. When diagnosing a fatal venous air embolism, scientific standards should be strictly followed. Adiagnosis made solely by histological examination was and is not possible according to the state of the art in forensic medicine and thus violates the principles of expert medical opinions
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