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11.
John Clifton-Brown Astley Hastings Moritz von Cossel Donal Murphy-Bokern Jon McCalmont Jeanette Whitaker Efi Alexopoulou Stefano Amaducci Larisa Andronic Christopher Ashman Danny Awty-Carroll Rakesh Bhatia Lutz Breuer Salvatore Cosentino William Cracroft-Eley Iain Donnison Berien Elbersen Andrea Ferrarini Judith Ford Jörg Greef Julie Ingram Iris Lewandowski Elena Magenau Michal Mos Martin Petrick Marta Pogrzeba Paul Robson Rebecca L. Rowe Anatolii Sandu Kai-Uwe Schwarz Danilo Scordia Jonathan Scurlock Anita Shepherd Judith Thornton Luisa M. Trindade Sylvia Vetter Moritz Wagner Pei-Chen Wu Toshihiko Yamada Andreas Kiesel 《Global Change Biology Bioenergy》2023,15(5):538-558
Demand for sustainably produced biomass is expected to increase with the need to provide renewable commodities, improve resource security and reduce greenhouse gas emissions in line with COP26 commitments. Studies have demonstrated additional environmental benefits of using perennial biomass crops (PBCs), when produced appropriately, as a feedstock for the growing bioeconomy, including utilisation for bioenergy (with or without carbon capture and storage). PBCs can potentially contribute to Common Agricultural Policy (CAP) (2023–27) objectives provided they are carefully integrated into farming systems and landscapes. Despite significant research and development (R&D) investment over decades in herbaceous and coppiced woody PBCs, deployment has largely stagnated due to social, economic and policy uncertainties. This paper identifies the challenges in creating policies that are acceptable to all actors. Development will need to be informed by measurement, reporting and verification (MRV) of greenhouse gas emissions reductions and other environmental, economic and social metrics. It discusses interlinked issues that must be considered in the expansion of PBC production: (i) available land; (ii) yield potential; (iii) integration into farming systems; (iv) R&D requirements; (v) utilisation options; and (vi) market systems and the socio-economic environment. It makes policy recommendations that would enable greater PBC deployment: (1) incentivise farmers and land managers through specific policy measures, including carbon pricing, to allocate their less productive and less profitable land for uses which deliver demonstrable greenhouse gas reductions; (2) enable greenhouse gas mitigation markets to develop and offer secure contracts for commercial developers of verifiable low-carbon bioenergy and bioproducts; (3) support innovation in biomass utilisation value chains; and (4) continue long-term, strategic R&D and education for positive environmental, economic and social sustainability impacts. 相似文献
12.
Gray SG Iglesias AH Lizcano F Villanueva R Camelo S Jingu H Teh BT Koibuchi N Chin WW Kokkotou E Dangond F 《The Journal of biological chemistry》2005,280(31):28507-28518
To effectively direct targeted repression, the class I histone deacetylases (HDACs) associate with many important regulatory proteins. In this paper we describe the molecular characterization of a member of the Jumonji domain 2 (JMJD2) family of proteins, and demonstrate its binding to both class I HDACs and the retinoblastoma protein (pRb). JMJD2 proteins are characterized by the presence of two leukemia-associated protein/plant homeodomain (LAP/PHD) zinc fingers, one JmjN, one JmjC (containing an internal retinoblastoma-binding protein 2 (RBBP2)-like sequence), and two Tudor domains. The first member of this group, JMJD2A, is widely expressed in human tissues and cell lines, and high endogenous expression of JMJD2A mRNA was found in several cell types, including human T-cell lymphotropic virus 1 (HTLV-1)-infected cell lines. JMJD2A and JMJD2B exhibit cell type-specific responses to the HDAC inhibitor trichostatin A. We show that the JMJD2A protein associates in vivo with pRb and class I HDACs, and mediates repression of E2F-regulated promoters. In HTLV-1 virus-infected cells, we find that JMJD2A binds to the viral Tax protein. Antibodies to JMJD2A recognize the native protein but also a half-sized protein fragment, the latter up-regulated in THP-1 cells during the G(2)/M phase of the cell cycle. The ability of JMJD2A to associate with pRb and HDACs and potentiate pRb-mediated repression of E2F-regulated promoters implies an important role for this protein in cell proliferation and oncogenesis. 相似文献
13.
Mystakidou K Parpa E Tsilika E Katsouda E Vlahos L 《Perspectives in biology and medicine》2005,48(1):95-104
Death has preoccupied humanity since before the dawn of civilization. As a multidimensional and moral problem, the end of life has concerned different civilizations, and different approaches to euthanasia, or "good death," have been developed in each culture. In Greece, there is a long record of the culture's evolving attitudes toward death and euthanasia.A more widespread knowledge of the views and traditions surrounding the act of euthanasia can contribute to a better understanding of the controversies surrounding modern attitudes and practice. 相似文献
14.
Karakitsos P Kyroudes A Pouliakis A Stergiou EB Voulgaris Z Kittas C 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2002,24(1):30-38
OBJECTIVE: To investigate the potential of artificial neural networks for cell identification in endometrial lesions from postmenopausal women. STUDY DESIGN: The study was performed on cytologic material obtained by the Gynoscann endometrial cell samplerfrom 12 cases of atrophic endometrium, 48 cases of hyperplasia without cytologic atypia (18 cases of simple hyperplasia and 30 cases of complex hyperplasia), 12 cases of hyperplasia with cytologic atypia (complex atypical hyperplasia) and 48 cases of adenocarcinoma (30 cases of well-differentiated, 12 cases of moderately differentiated and 6 cases of poorly differentiated carcinoma). From each case approximately 100 cells were examined using a custom image analysis system. A learning vector quantizer (LVQ) identified the collected data. RESULTS: Investigation of cells from Endometrial Alterations with LVQ proved that according to the nuclear characteristics, as expressed by morphometric and textural measures, the endometrial cells from postmenopausal women may be identified as belonging to one of thefollowing three groups: atrophy, hyperplasia without cytologic atypia (simple and complex hyperplasia) and malignant neoplastic lesions (atypical complex and adenocarcinoma). CONCLUSION: The role of nuclear morphologic features in the cytologic diagnosis of endometrial alterations was confirmed. The overlap in thefeature space observed indicates that cell characteristics do not form strictly separate clusters. Thatfact explains the difficulty that morphologists have with the reproducible identification of cells from endometrial lesions in postmenopausal women. Application of LVQ offers a good classification at the cell level and promises to be a powerful toolfor classification on the individual patient level andfor the clarification of the natural history of endometrial pathology. 相似文献
15.
Kapou A Benetis NP Avlonitis N Calogeropoulou T Koufaki M Scoulica E Nikolaropoulos SS Mavromoustakos T 《Bioorganic & medicinal chemistry》2007,15(3):1252-1265
The application of 2D-NMR spectroscopy and Molecular Modeling in determining the active conformation of flexible molecules in 3D-QSAR was demonstrated in the present study. In particular, a series of 33 flexible synthetic phospholipids, either 2-(4-alkylidene-cyclohexyloxy)ethyl- or omega-cycloalkylidene-substituted ether phospholipids were systematically evaluated for their in vitro antileishmanial activity against the promastigote forms of Leishmania infantum and Leishmania donovani by CoMFA and CoMSIA 3D-QSAR studies. Steric and hydrophobic properties of the phospholipids under study appear to govern their antileishmanial activity against both strains, while the electrostatic properties have no significant contribution. The acknowledgment of these important properties of the pharmacophore will aid in the rational design of new analogues with higher activity. 相似文献
16.
A characteristic posture is considered one of the behavioral hallmarks of sleep, and typically includes functional features such as support for the limbs and shielding of sensory organs. The nematode C. elegans exhibits a sleep-like state during a stage termed lethargus, which precedes ecdysis at the transition between larval stages. A hockey-stick-like posture is commonly observed during lethargus. What might its function be? It was previously noted that during lethargus, C. elegans nematodes abruptly rotate about their longitudinal axis. Plausibly, these “flips” facilitate ecdysis by assisting the disassociation of the old cuticle from the new one. We found that body-posture during lethargus was established using a stereotypical motor program and that body bends during lethargus quiescence were actively maintained. Moreover, flips occurred almost exclusively when the animals exhibited a single body bend, preferentially in the anterior or mid section of the body. We describe a simple biomechanical model that imposes the observed lengths of the longitudinally directed body-wall muscles on an otherwise passive elastic rod. We show that this minimal model is sufficient for generating a rotation about the anterior-posterior body axis. Our analysis suggests that posture during lethargus quiescence may serve a developmental role in facilitating flips and that the control of body wall muscles in anterior and posterior body regions are distinct. 相似文献
17.
Kathryn T. Hall Anthony J. Lembo Irving Kirsch Dimitrios C. Ziogas Jeffrey Douaiher Karin B. Jensen Lisa A. Conboy John M. Kelley Efi Kokkotou Ted J. Kaptchuk 《PloS one》2012,7(10)
Identifying patients who are potential placebo responders has major implications for clinical practice and trial design. Catechol-O-methyltransferase (COMT), an important enzyme in dopamine catabolism plays a key role in processes associated with the placebo effect such as reward, pain, memory and learning. We hypothesized that the COMT functional val158met polymorphism, was a predictor of placebo effects and tested our hypothesis in a subset of 104 patients from a previously reported randomized controlled trial in irritable bowel syndrome (IBS). The three treatment arms from this study were: no-treatment (“waitlist”), placebo treatment alone (“limited”) and, placebo treatment “augmented” with a supportive patient-health care provider interaction. The primary outcome measure was change from baseline in IBS-Symptom Severity Scale (IBS-SSS) after three weeks of treatment. In a regression model, the number of methionine alleles in COMT val158met was linearly related to placebo response as measured by changes in IBS-SSS (p = .035). The strongest placebo response occurred in met/met homozygotes treated in the augmented placebo arm. A smaller met/met associated effect was observed with limited placebo treatment and there was no effect in the waitlist control. These data support our hypothesis that the COMT val158met polymorphism is a potential biomarker of placebo response. 相似文献
18.
Background
The aim of this study was to examine whether exposure to human suffering is associated with negative changes in perceptions about personal health. We further examined the relation of possible health perception changes, to changes in five discrete emotions (i.e., fear, guilt, hostility/anger, and joviality), as a guide to understand the processes underlying health perception changes, provided that each emotion conveys information regarding triggering conditions.Methodology/Findings
An experimental group (N = 47) was exposed to images of human affliction, whereas a control group (N = 47) was exposed to relaxing images. Participants in the experimental group reported more health anxiety and health value, as well as lower health-related optimism and internal health locus of control, in comparison to participants exposed to relaxing images. They also reported more fear, guilt, hostility and sadness, as well as less joviality. Changes in each health perception were related to changes in particular emotions.Conclusion
These findings imply that health perceptions are shaped in a constant dialogue with the representations about the broader world. Furthermore, it seems that the core of health perception changes lies in the acceptance that personal well-being is subject to several potential threats, as well as that people cannot fully control many of the factors the determine their own well-being. 相似文献19.
Leaf color in some individuals of Cistus creticus turns transiently to red during winter, while neighboring individuals occupying the same site remain green. We have examined whether anthocyanin accumulation can be associated with variations in photosynthetic and/or photoprotective characteristics between the two phenotypes, rendering the red phenotype more vulnerable to photoinhibition and, accordingly, needing additional protection in the form of anthocyanins. Towards this aim, maximum (pre-dawn) and effective (mid-day) PSII photochemical efficiencies, xanthophyll cycle pool sizes and leaf nitrogen contents were seasonably followed, encompassing both the green (spring, summer, autumn) and the red (winter) period of the year. Moreover, the distribution of the two phenotypes in exposed and shaded sites was assessed. The frequency of red individuals was considerably higher in fully exposed sites, pointing to a photoprotective function of leaf anthocyanins. Yet, the assumption was not corroborated by pre-dawn PSII yield measurements, since both phenotypes displayed similar high values throughout the year and a similar drop during winter. However, the red phenotype was characterized by lower light-saturated PSII yields, xanthophyll cycle pool sizes and leaf nitrogen, during both the green and the red period of the year. Based on this correlative evidence, we suggest that winter redness in C. creticus may compensate for an inherent photosynthetic and photoprotective inferiority, possibly through a light screen and/or an antioxidant function of leaf anthocyanins. 相似文献
20.
Reflectance indices are frequently used for the nondestructive assessment of leaf chemistry, especially pigment content, in environmental or developmental studies. Since reflectance spectra are influenced by trichome density, and trichome density displays a considerable phenotypic plasticity, we asked whether this structural parameter could be a source of variation in the values of the most commonly used indices. Trichome density was manipulated in detached leaves of three species having either peltate (Olea europaea and Elaeagnus angustifolius) or tubular (Populus alba) trichomes by successive removal of hairs. After each dehairing step, trichome density was determined by light or scanning electron microscopy and reflectance spectra were obtained with a diode-array spectrometer. Although species-specific differences were evident, most of the indices were considerably affected even at low trichome densities. In general, the less-affected indices were those using wavebands within the visible spectral region. The index that could be safely used even at very high hair densities in all species was the red edge index (lambda(RE)) for chlorophyll. The results indicate that changes in reflectance indices should be interpreted cautiously when concurrent changes in trichome density are suspected. In this case, the red edge for chlorophyll content may be the index of choice. 相似文献