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Advances in Plant-Hemipteran Interactions

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889453214 Year: Pages: 236 DOI: 10.3389/978-2-88945-321-4 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Botany
Added to DOAB on : 2018-02-27 16:16:45
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Hemipterans encompass a large group of insect pests of plants that utilize mouthparts which are modified for piercing and consuming fluids from plants. In addition, hemipterans vector viral and bacterial diseases of plants. This book brings together a set of reviews and research papers that showcase the the range of activities being undertaken to advance our understanding of the multi-organismal interaction between plant, hemipterans and microbes.

Assessing Prenatal and Neonatal Gonadal Steroid Exposure for Studies of Human Development: Methodological and Theoretical Challenges

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889196074 Year: Pages: 80 DOI: 10.3389/978-2-88919-607-4 Language: English
Publisher: Frontiers Media SA
Subject: Medicine (General) --- Internal medicine
Added to DOAB on : 2016-08-16 10:34:25
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There is extensive evidence from animal models that gonadal steroids, produced in fetal and neonatal life, act on the developing organism to produce sex differences far beyond the reproductive system. That early gonadal steroid exposure also plays an important role in human development is supported by studies of individuals with disorders of sex determination and differentiation. It is much less clear whether normal variation in gonadal steroid exposure predicts sexually dimorphic health outcomes or within-sex variation. This is largely due to challenges related to the assessment of gonadal steroid exposure in the developing fetus and neonate. Regarding the prenatal period, serial measurements of serum hormone levels in the fetus, for use in studies of later development, are not possible for ethical reasons. Researchers have measured hormones in maternal blood, umbilical cord blood, and amniotic fluid; used putative anthropometric indices such as the relative lengths of the 2nd and 4th digits (2D:4D); evaluated common variants in genes related to hormone production, transport, and metabolism; and examined development in opposite sex twins and the offspring of mothers with hyperandrogeny. Each of these approaches has particular strengths and notable weaknesses. Regarding the neonatal period, serial measurements in serum are often impractical for studies of typical development. Salivary hormone assays, frequently used in studies of older children and adults, have not been extensively investigated in neonates. The most appropriate timing for testing is also open to debate. Early work suggested that testosterone levels in males begin to rise after the first postnatal week, peak around the 3rd to 4th months of life, and then drop back to very low levels by 1 year. However a more recent study of 138 infants did not demonstrate this pattern. Testosterone was highest on the day of birth and gradually dropped over the first 6 months. Even less is known about patterns of early estrogen exposure, though highly sensitive bioassays indicated that sex differences are present in early childhood. In addition, the design and interpretation of studies may be impacted by widespread acceptance of conceptual frameworks that are not well-supported empirically. For example, many researchers presume that the free hormone hypothesis, which states that unbound hormone is more readily diffusible into tissues and thus a better measure of actual exposure, is true. However this hypothesis has been challenged on multiple grounds. A second example: it is generally accepted that masculinization of the human brain is primarily mediated by the androgen receptor (in contrast to rodents where the estrogen receptor plays a major role), in part because chromosomal males with complete androgen insensitivity generally espouse a female gender identity. However this is not always the case, and other sexually dimorphic outcomes have not been carefully assessed in CAIS. The aim of this research topic is to gather together experimental and review papers which address the diverse challenges in assessing prenatal and neonatal gonadal steroid exposure for studies of human development with the expectation that this will allow more critical appraisal of existing studies, identify critical research gaps, and improve the design of future studies.

Positive Aspects of Animal Welfare

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ISBN: 9783039285327 / 9783039285334 Year: Pages: 180 DOI: 10.3390/books978-3-03928-533-4 Language: eng
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Science (General) --- Biology --- Animal Sciences
Added to DOAB on : 2020-06-09 16:38:57
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Comfort during resting, half-closed eyes when feeding on highly palatable feed, or vigorous tail wagging when being brushed are some of the positive indicators that can be used to evaluate the quality of the environment in which domestic animals live. This has been a radical shift from the past as, until now, the welfare assessment on farms has meant assessing negative indicators, namely the number of lame animals, presence of lesions, or frequency of agonistic behaviours. However, the latest research confirms that the absence of a problem or of suffering does not necessarily imply that the animals are experiencing a good life and that their level of welfare is high. To guarantee high welfare standards, animals should experience positive conditions that allow them to live a “life worth living”, and positive indicators are needed to identify these conditions. This Special Issue focuses on the development and validation of indicators of positive welfare or on the refinement of the existing ones, as well as on the identification of suitable living conditions for providing positive welfare to farmed and companion animals.

Intrinsically Biocompatible Polymer Systems

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ISBN: 9783039284207 9783039284214 Year: Pages: 270 DOI: 10.3390/books978-3-03928-421-4 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Technology (General) --- General and Civil Engineering --- Materials
Added to DOAB on : 2020-04-07 23:07:09
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Biocompatibility refers to the ability of a biomaterial to perform its desired function with respect to a medical therapy, without eliciting any undesirable local or systemic effects in the recipient or beneficiary of that therapy, but generating the most appropriate beneficial cellular or tissue response in that specific situation, and optimizing the clinically relevant performance of that therapy, which reflects current developments in the area of intrinsically biocompatible polymer systems. Polymeric biomaterials are presently used as, for example, long-term implantable medical devices, degradable implantable systems, transient invasive intravascular devices, and, recently, as tissue engineering scaffolds. This Special Issue welcomes full papers and short communications highlighting the aspects of the current trends in the area of intrinsically biocompatible polymer systems.

Keywords

antimicrobial peptides --- biodegradable polymers --- biocompatible polymers --- drug delivery systems --- controlled release --- citropin --- temporin --- ionic liquids --- chitooligosaccharide --- polyurethane --- biodegradability --- physicochemical properties --- hemocompatibility --- biological activity --- crosslinking --- drug delivery --- cosmetic --- food-supplement --- functionalization --- hyaluronan applications --- hyaluronan derivatives --- hyaluronan synthases --- hyaluronic acid --- hyaluronidases --- physico-chemical properties --- cyclohexanone --- ?-butyrolactone --- chloroform --- extraction --- polyhydroxyalkanoates --- PHB --- electrospraying --- biodegradable nano/microparticles --- drug delivery --- septic arthritis --- release characteristics --- biopolymers --- silk fibroin --- konjac glucomannan --- porous beads --- scaffolds --- tissue engineering --- microcarriers --- Poly (l-lactic) acid --- Chitosan --- nanohydroxyapatite --- osteoblasts --- ion-releasing materials --- shrinkage stress --- water sorption --- hydroscopic expansion --- photoelastic investigation --- enzymatic polymerization --- chemical polymerization --- poly(benzyl malate) --- biocompatible nanoparticles --- cell uptake --- cytotoxicity --- HepaRG cells --- human macrophages --- star polymers --- solution behavior --- ATRP --- SPION --- contrast agent --- MRI --- cancer diagnosis --- folate receptor --- pluronic F127 --- polylactide --- hydrolytic degradation --- mechanical properties --- PEEK copolymer synthesis --- PEEK composite --- Spine cage application --- In vitro biosafety --- degradation --- saliva --- mechanical properties --- molecular weight --- thermal properties --- activation energy of thermal decomposition --- anterior cruciate ligament reconstruction --- bone tunnel enlargement --- X-ray microtomography --- polylactide --- n/a

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