213 research outputs found
Základy půdní úrodnosti
Zvyšování půdní úrodnosti bylo pro průkopníky ekologického zemědělství základem veškerého jejich úsilí. Přesto zachování úrodné půdy mnohdy nebyla věnována dostatečná pozornost. Ekologické zemědělství je však na přirozené půdní úrodnosti závislé.
Oslabená a poškozená půda nám nemůže poskytnout to, co od ní očekáváme. Udržet úrodnost půdy vyžaduje velkou péči. Předkládaná brožura ukazuje půdní úrodnost z různých úhlů pohledu. Naším záměrem však nebylo vytvořit obecně platný „návod k použití“. Informace mají být mnohem spíše podnětem k tomu, aby se o vztahu člověka k půdě smýšlelo jinak a aby se tento vztah utvářel ve prospěch budoucnosti
The structure of mercantile communities in the Roman world : how open were Roman trade networks?
Differing member state approaches to the development of the EU Battlegroup Concept: implications for CSDP
Phenotyping male infertility in the mouse: how to get the most out of a ‘non-performer’
BACKGROUND: Functional male gametes are produced through complex processes that take place within the testis, epididymis and female reproductive tract. A breakdown at any of these phases can result in male infertility. The production of mutant mouse models often yields an unexpected male infertility phenotype. It is with this in mind that the current review has been written. The review aims to act as a guide to the 'non-reproductive biologist' to facilitate a systematic analysis of sterile or subfertile mice and to assist in extracting the maximum amount of information from each model. METHODS: This is a review of the original literature on defects in the processes that take a mouse spermatogonial stem cell through to a fully functional spermatozoon, which result in male infertility. Based on literature searches and personal experience, we have outlined a step-by-step strategy for the analysis of an infertile male mouse line. RESULTS: A wide range of methods can be used to define the phenotype of an infertile male mouse. These methods range from histological methods such as electron microscopy and immunohistochemistry, to hormone analyses and methods to assess sperm maturation status and functional competence. CONCLUSION: With the increased rate of genetically modified mouse production, the generation of mouse models with unexpected male infertility is increasing. This manuscript will help to ensure that the maximum amount of information is obtained from each mouse model and, by extension, will facilitate the knowledge of both normal fertility processes and the causes of human infertility
The dynamic cilium in human diseases
Cilia are specialized organelles protruding from the cell surface of almost all mammalian cells. They consist of a basal body, composed of two centrioles, and a protruding body, named the axoneme. Although the basic structure of all cilia is the same, numerous differences emerge in different cell types, suggesting diverse functions. In recent years many studies have elucidated the function of 9+0 primary cilia. The primary cilium acts as an antenna for the cell, and several important pathways such as Hedgehog, Wnt and planar cell polarity (PCP) are transduced through it. Many studies on animal models have revealed that during embryogenesis the primary cilium has an essential role in defining the correct patterning of the body. Cilia are composed of hundreds of proteins and the impairment or dysfunction of one protein alone can cause complete loss of cilia or the formation of abnormal cilia. Mutations in ciliary proteins cause ciliopathies which can affect many organs at different levels of severity and are characterized by a wide spectrum of phenotypes. Ciliary proteins can be mutated in more than one ciliopathy, suggesting an interaction between proteins. To date, little is known about the role of primary cilia in adult life and it is tempting to speculate about their role in the maintenance of adult organs. The state of the art in primary cilia studies reveals a very intricate role. Analysis of cilia-related pathways and of the different clinical phenotypes of ciliopathies helps to shed light on the function of these sophisticated organelles. The aim of this review is to evaluate the recent advances in cilia function and the molecular mechanisms at the basis of their activity
Female gaming, gaming addiction, and the role of women within gaming culture
Research investigating female gaming has begun to emerge despite gaming being traditionally more popular with males. Research in the 21st century has drawn attention to the role of women in culture, society, and technology, and female gaming is one of the growing phenomena not to have been researched in depth. The aim of the present paper was to review female gaming (i.e., the role of females within video game culture) and identify any associated psychopathological symptomatology. The review adapted the Sample, Phenomenon of Interest, Design, Evaluation, Research (SPIDER) model in conducting a narrative literature review. A search of three scientific electronic databases yielded 49 papers for further evaluation. From a methodological perspective, studies had to fulfill the following criteria to be included: i) published between the years 2000 and 2018; ii) assessed female gaming or the female position within gaming culture, iii) contained quantitative, qualitative, or mixed methods approaches to produce empirical data or discuss theoretical implications through reviews, iv) be retrievable as a full-text peer-reviewed journal paper, and v) published in English, German, Polish, Spanish, Italian, Portuguese, or French. Four categories emerged from the papers: i) the benefits of female gaming, ii) why women might play video games less than men, iii) perceptions and realities of female characters within video games, and iv) women’s position in gaming culture. The main findings showed playing video games has benefits for women in terms of enhancing cognitive, social, and physical abilities. However, they are less encouraged to play video games due to negative expectations based on gender and/or experiences during game play. Video games are associated with stereotypical male characteristics, such as being overly aggressive, and frequently contain sexualized content. Female gamers appear to require coping strategies to handle online harassment. Females look for different things in video games, which are not often included in game designs thereby limiting their abilities. For instance, female avatar representation—which is exaggerated and hypersexualized—can prompt social comparisons and lead to feelings of decreased self-esteem, depression, and other impacts on well-being. Overall, there are still obstacles for women playing video games even though they comprise half of the gaming population
Practical clinical and diagnostic pathway for the investigation of the infertile couple
Capsule: This expert opinion summarizes current knowledge on risk factors for infertility and identifies a practical clinical and diagnostic approach for the male and female partners of an infertile couple aimed to improve the investigation and management of fertility problems.
Background: Infertility represents an important and growing health problem affecting up to 16% of couples worldwide. In most cases, male, female, or combined factor can be identified, and different causes or risk factors have been related to this condition. However, there are no standardized guidelines on the clinical-diagnostic approach of infertile couples and the recommendations concerning infertility are sometimes lacking, incomplete, or problematic to apply.
Objective: The aim of this work is to provide an appropriate clinical and diagnostic pathway for infertile couples designed by a multidisciplinary-team of experts. The rationale is based on the history and physical examination and then oriented on the basis of initial investigations. This approach could be applied in order to reduce variation in practice and to improve the investigation and management of fertility problems.
Methods: Prominent Italian experts of the main specialties committed in the ART procedures, including gynecologists, andrologists, embryologists, biologists, geneticists, oncologists, and microbiologists, called “InfertilItaly group”, used available evidence to develop this expert position.
Outcomes: Starting from the individuation of the principal risk factors that may influence the fertility of females and males and both genders, the work group identified most appropriate procedures using a gradual approach to both partners aimed to obtain a precise diagnosis and the most effective therapeutic option, reducing invasive and occasionally redundant procedures.
Conclusions: This expert position provides current knowledge on risk factors and suggests a diagnostic workflow of infertile couples. By using this step-by-step approach, health care workers involved in ART, may individuate a practical clinical management of infertile couples shared by experts
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