988 resultados para ALTERNATIVE REPRODUCTIVE TACTICS


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Selostus: Maatalouspolitiikkauudistusten vaikutuksista pellonkäytön diversiteettiin

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Assisted reproductive technologies (ART) predispose the offspring to vascular dysfunction, arterial hypertension, and hypoxic pulmonary hypertension. Recently, cardiac remodeling and dysfunction during fetal and early postnatal life have been reported in offspring of ART, but it is not known whether these cardiac alterations persist later in life and whether confounding factors contribute to this problem. We, therefore, assessed cardiac function and pulmonary artery pressure by echocardiography in 54 healthy children conceived by ART (mean age 11.5 ± 2.4 yr) and 54 age-matched (12.2 ± 2.3 yr) and sex-matched control children. Because ART is often associated with low birth weight and prematurity, two potential confounders associated with cardiac dysfunction, only singletons born with normal birth weight at term were studied. Moreover, because cardiac remodeling in infants conceived by ART was observed in utero, a situation associated with increased right heart load, we also assessed cardiac function during high-altitude exposure, a condition associated with hypoxic pulmonary hypertension-induced right ventricular overload. We found that, while at low altitude cardiac morphometry and function was not different between children conceived by ART and control children, under the stressful conditions of high-altitude-induced pressure overload and hypoxia, larger right ventricular end-diastolic area and diastolic dysfunction (evidenced by lower E-wave tissue Doppler velocity and A-wave tissue Doppler velocity of the lateral tricuspid annulus) were detectable in children and adolescents conceived by ART. In conclusion, right ventricular dysfunction persists in children and adolescents conceived by ART. These cardiac alterations appear to be related to ART per se rather than to low birth weight or prematurity.

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This paper presents a detailed description of the reproductive characters of Mediterranean Seirospora giraudyi based on fresh material collected in the northwestern coast of Spain. Vegetative cells are uninucleate. The plant is monoecious. Spermantangial parent’s cells are clustered on modified dwarf determinate filaments, usually situated on adaxial surfaces of branches. One to four spermatia are formed by elongation and proximal divisions of the spermatangial parent cells. Spermatium with a nucleus situated ina mec. The thallus is procarpic. The four-celled carpogonial branch is initially L-shaped, and it is situated on a periaxial supporting fertile axial cell. The mature carpogonial branch is U-shaped and the supporting cell and second periaxial cell enlarge and divide transversely to reproduce a pair uninicleate auxiliary cell. The nucleus in the ferlilized carpogonium divides twice and the carpogonium cleaves vertically into two cells that, turn, cut off a pair of uninucleate connecting cells that fuse with the auxiliary cells on opposite sides; the diploid nuclei in the connecting cells divide at the site of fusion and one of the nuclei enters the auxiliary cell white the other is extruded. Each auxiliary cell gives to a terminal primary gonimolobe initials. Gonimolobes form lax chains of carposporangia. As the gonimoblasts mature, both lobes of the foot cell which is situated on the supporting cell elongate the upper one secondary connecting with the supporting cell, and the lower one with the fertile axial cell. The gonimoblasts are subtended at maturity by one to several clusters of involucral flaments. Seirospora is currently placed in the tribe Euptiloteae; however the reproductive character of S.giraudyi is dentical to those described for the Cañllithamnieae. Molecular studies are needed to confirm the taxonomic position of S.giraudyi as well as that of the other species placed Seirospora

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We studied the reproductive cycle of the sea urchin Arbacia lixula in a subtidal population from northeast Spain over four years using a gonadosomatic index (GSI) and gonad histology. Our results show that the GSI of A. lixula follows a seasonal cycle which peaks in May-July and attains its lowest values in October-November every year. The time course of the GSI matched closely the photoperiod cycle. We also found a remarkable inter-annual variability in the maximum value of GSI, which correlated with mean water temperature during the gonad growth period (winter and spring). Gonad histology was also in agreement with a single gametogenic cycle per year in this species. We explored the application of circular statistics to present and analyse gonadal development data, which allowed us to adequately handle the high intra-individual variability detected, with several developmental stages commonly found within the same gonad. The picture that emerged is one of a gametogenic timing driven by photoperiod, while the amount of reproductive output is determined by temperature. This is coherent with the tropical origin of the species and lends support to recent warnings about an increase in the abundance of this species in the Mediterranean as a result of global warming, with associated increased impact potential in sublittoral communities.

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Hintergrund: Die physiologische Phimose ist bereits bei der Geburt vorhanden und wächst sich in den meisten Fällen aus. Während 10% der Knaben im Alter von drei Jahren noch eine Phimose haben, nimmt diese Prävalenz auf 6-8% im Alter von sieben Jahren und 1% im Alter von 16 Jahren ab. Man spricht von einer pathologischen Phimose, wenn die Vorhaut Vernarbungen infolge von wiederholten Entzündungen oder forcierten Retraktionsversuchen aufweist. Dennoch ist die Unterscheidung zwischen pathologischer und physiologischer Phimose schwierig, und eine chirurgische Behandlung (Zirkumzision, Vorhautplastik) ist häufig. Eine topische Kortikosteroidbehandlung wird seit mehreren Jahren wegen seiner anti-inflammatorischen und immunsuppressiven Wirkung (Verminderung der Kollagenproduktion) angewendet. Es gibt aber keine Evidenz bezüglich Wirksamkeit und Sicherheit dieser Behandlung.

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Question clinique: Une mère vous consulte avec son fils âgé de 6 ans, en bonne santé habituelle mais connu pour un phimosis. Il ne présente pas de troubles mictionnels, ni d'antécédents de balanite ou de paraphimosis. Sa mère est inquiète de voir le phimosis persister et vous demande s'il existe une alternative au traitement chirurgical. Contexte: Présent dès la naissance, le phimosis physiologique se résout spontanément dans la majorité des cas. Alors que 10% des garçons présentent un phimosis à l'âge de 3 ans, cette prévalence diminue à 6-8% à l'âge de 7 ans, pour atteindre 1% à l'âge de 16 ans. On parle de phimosis pathologique lorsque le prépuce présente des cicatrices fibreuses suite à des inflammations répétées ou des décalottages forcés. Cependant, la distinction clinique entre un phimosis pathologique et physiologique est difficile et le traitement chirurgical reste fréquent. Un traitement par corticostéroïdes topiques est utilisé depuis de nombreuses années pour son action anti-inflammatoire et immunosuppressive (diminution de la production de collagène). Pourtant, il n'existe pas de preuve quant à l'efficacité et la sécurité de ce traitement.

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Perinteisten markkinointiviestintäkanavien menettäessä jatkuvasti tehoaan mediakentän ja kohderyhmien sirpaloituessa yhä pienempiin yksiköihin markkinointiorganisaatiot etsivät vaihtoehtoisia tapoja tavoittaakseen kohdeyleisönsä. Yksi vaihtoehtoinen markkinointiviestintäkeino on tuotesijoittelu (product placement), jossa (merkki)tuotteita sijoitetaan erilaisten viihdetuotantojen, kuten elokuvien, televisio-ohjelmien ja tietokonepelien, tarinan yhteyteen, jotta yhä medialukutaitoisempi kohdeyleisö ei pystyisi välttämään kaupallista viestiä esimerkiksi vaihtamalla televisiokanavaa tai kääntämällä lehden sivua. Koska tuote on sijoitettu kerrottavan tarinan sisään, markkinointiviestin — eli tuotteen havaitsemisen — välttäminen on huomattavasti vaikeampaa kuin perinteisten markkinointiviestintämenetelmien kohdalla. Lisäksi, sijoitellut tuotteet ovat tavallisesti kiinteässä yhteydessä tarinan juonen ja henkilöhahmojen kanssa siten, että tuote saa näistä yhteyksistä positiivista vahvistusta imagolleen. Pro Gradu-tutkielman tarkoituksena oli selvittää tuotesijoittelun käyttökelpoisuutta markkinointiviestinnässä sekä miten kulutushyödykemarkkinoijat voivat hyödyntää menetelmää markkinointiviestintästrategioissaan. Tuotesijoittelun poikkeava luonne markkinointiviestintävälineenä tuotti kysymyksen miten tuotesijoittelua voitaisiin hyödyntää yhteistyössä muiden markkinointiviestintäkeinojen kanssa. Tätä varten tutkimuksessa tuotesijoittelu yhdistettiin integroidun markkinointiviestinnän (IMC) viitekehykseen. IMC-konsepti syntyi markkinointiviestinnässä vastaamaan samaan tarpeeseen kuin tuotesijoittelukin: pirstaloitunut mediakenttä ja yksittäiset kohderyhmät vaativat kehittyneempää ja yhtenäisempää markkinointiviestinnän suunnittelua ja toteutusta. Tutkimuksen johtopäätöksenä tuotesijoittelu todettiin käyttökelpoiseksi markkinointiviestintäkeinoksi mikäli viestinnän tavoitteena on muu kuin tuotteen myyntiin suorasti vaikuttaminen. Tuotesijoittelu on sen sijaan erittäin tehokas tuotetietoisuuden lisäämisessä, erityisesti tunnistamisen kohdalla. Tuotesijoittelu voi myös tuottaa suoran ostotarpeen mutta tällöin viestin vastaanottajalla täytyy olla vallitseva tarve kyseisen tuoteryhmän osalta ennen altistumista ko. markkinointiviestille. Tuotesijoittelu voidaan sisällyttää IMC-suunnitteluprosessiin markkinointiviestintästrategian kiinteänä osana. Integraatio markkinointiviestinnässä siten, että tuotesijoittelua tuettaisiin muilla viestintäkeinoilla yhtenäisen kampanjan kehittämiseksi on kuitenkin paljon ennakoitua harvinaisempaa, johtuen ehkä eniten tuotesijoittelun poikkeuksellisesta luonteesta ja kyseisen viestintämuodon vaikeasta hallittavuudesta markkinoijan taholta. Tutkimus toteutettiin normatiivisena case-tutkimuksena pääasiassa sekundäärisiä tietolähteitä hyödyntäen. Case-tutkimuksia varten kerättiin primääristä tietoa kyselylomakkeella kahdesta tuotesijoittelua käyttävästä kansainvälisestä yhtiöstä, jonka lisäksi myös sekundäärisiä tietolähteitä hyödynnettiin case-osan tiedonkeruussa.

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Viticulture is an important agricultural activity in semiarid northeastern Brazil, and the quality and ease of vine propagation are very important in this context. This study evaluated the use of 2,4-dichlorophenoxyacetic acid (2,4-D) as an alternative to indolebutyric acid (IBA) in the rooting of vine rootstock cuttings. The trial was conducted at the Universidade Federal de Sergipe (São Cristóvão-SE) between January and March 2010 with cuttings of the rootstocks of 'IAC-766', 'IAC-572', and 'Paulsen 1103' treated with 2,4-D or IBA applied at concentrations of 0, 1000, 2000, or 3000 rng-L-1 for 5 s and planted in a field on washed sand. At 56 days after planting, the percentages of rooted, sprouted, callused, and dead cuttings were evaluated, and also the average number and length of the rooted cuttings. The results showed that 2,4-D was not superior to IBA in the characteristics wanted for the rooting process of the vine rootstock cuttings. The vine rootstocks showed potential for propagation by cutting without auxin application. It was observed that the high concentrations were the worst for the rooting of the cuttings.

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Flowers of Annonaceae are characterized by fleshy petals, many stamens with hard connective shields and numerous carpels with sessile stigmas often covered by sticky secretions. The petals of many representatives during anthesis form a closed pollination chamber. Protogynous dichogamy with strong scent emissions especially during the pistillate stage is a character of nearly all species. Scent emissions can be enhanced by thermogenesis. The prevailing reproductive system in the family seems to be self-compatibility. The basal genus Anaxagorea besides exhibiting several ancestral morphological characters has also many characters which reappear in other genera. Strong fruit-like scents consisting of fruit-esters and alcohols mainly attract small fruit-beetles (genus Colopterus, Nitidulidae) as pollinators, as well as several other beetles (Curculionidae, Chrysomelidae) and fruit-flies (Drosophilidae), which themselves gnaw on the thick petals or their larvae are petal or ovule predators. The flowers and the thick petals are thus a floral brood substrate for the visitors and the thick petals of Anaxagorea have to be interpreted as an antipredator structure. Another function of the closed thick petals is the production of heat by accumulated starch, which enhances scent emission and provides a warm shelter for the attracted beetles. Insight into floral characters and floral ecology of Anaxagorea, the sister group of the rest of the Annonaceae, is particularly important for understanding functional evolution and diversification of the family as a whole. As beetle pollination (cantharophily) is plesiomorphic in Anaxagorea and in Annonaceae, characters associated with beetle pollination appear imprinted in members of the whole family. Pollination by beetles (cantharophily) is the predominant mode of the majority of species worldwide. Examples are given of diurnal representatives (e.g., Guatteria, Duguetia, Annona) which function on the basis of fruit-imitating flowers attracting mainly fruit-inhabiting nitidulid beetles, as well as nocturnal species (e.g., large-flowered Annona and Duguetia species), which additionally to most of the diurnal species exhibit strong flower warming and provide very thick petal tissues for the voracious dynastid scarab beetles (Dynastinae, Scarabaeidae). Further examples will show that a few Annonaceae have adapted in their pollination also to thrips, flies, cockroaches and even bees. Although this non-beetle pollinated species have adapted in flower structure and scent compounds to their respective insects, they still retain some of the specialized cantharophilous characters of their ancestors.

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The effect of diet on barn owl (Tyto alba) breeding biology has been well studied in the temperate regions but not in the more arid Middle East. In temperate regions, barn owls are darker colored and mainly prey upon Cricetidae rodents, whereas in arid regions, they are lighter colored and prey to a larger degree upon Muridae rodents. In this study we analyzed the diet and breeding success of 261 barn owl pairs nesting in Israel. The reproductive success of barn owls declined from March to August, and fledged more young when they consumed a larger proportion of social voles (Microtus socialis guentheri). Although the diet of the lighter colored barn owls in Israel comprises more Muridae than that of the darker morphs in temperate regions, in both regions the number of barn owl young increases with an increased proportion of voles in the diet.

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Parthenogenesis - the ability to produce offspring from unfertilized eggs - is widespread among invertebrates and now increasingly found in normally sexual vertebrates. Are these cases reproductive errors or could they be a first step in the emergence of new parthenogenetic lineages?

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In the past f ew years numerous authors have examined how the current economic crisis in Spain has dif f erential impacts on women and men.1 While this is important to show, this article’s goal is to make the leap f rom a mere description of the gendered effects of the crisis, to an analysis of some of the very gendered processes that shape it at its core. In other words, the intent is to understand how both the crisis itself and the ways the state manages it are structurally shaped by gender.

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Background: The use of complementary and alternative medicine (CAM) and complementary and alternative therapies (CAT) during pregnancy is increasing. Scientific evidence for CAM and CAT in the field of obstetrics mainly covers pain relief in labor. Midwives are responsible for labor and delivery care: hence, their knowledge of CAM and CAT is important. The aims of this study are to describe the professional profile of midwives who provide care for natural childbirth in Catalan hospitals accredited as centers for normal birth, to assess midwives" level of training in CAT and their use of these therapies, and to identify specific resources for CAT in labor wards. Methods: A descriptive, cross-sectional, quantitative method was used to assess the level of training and use of CAT by midwives working at 28 hospitals in Catalonia, Spain, accredited as public normal birth centers. Results: Just under a third of midwives (30.4%) trained in CAT after completion of basic training. They trained in an average of 5.97 therapies (SD 3.56). The number of CAT in which the midwives were trained correlated negatively with age (r = - 0.284; p < 0.001) and with their time working at the hospital in years (r = - 0.136; p = 0.036). Midwives trained in CAT considered that the following therapies were useful or very useful for pain relief during labor and delivery: relaxation techniques (64.3%), hydrotherapy (84.8%) and the application of compresses to the perineum (75.9%). The availability of resources for providing CAT during normal birth care varied widely from center to center. Conclusions: Age may influence attitudes towards training. It is important to increase the number of midwives trained in CAM for pain relief during childbirth, in order to promote the use of CAT and ensure efficiency and safety. CAT resources at accredited hospitals providing normal childbirth care should also be standardized.