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991.
992.
Tuczinski Marc Saravia Florencia Horn Harald 《Bioprocess and biosystems engineering》2018,41(11):1561-1571
Bioprocess and Biosystems Engineering - For an undisturbed operation of two-stage high-pressure fermentation up to 100 bar, a particle-free hydrolysate appears to be necessary. This is... 相似文献
993.
Deletion of FtsH11 protease has impact on chloroplast structure and function in Arabidopsis thaliana when grown under continuous light 下载免费PDF全文
Raik Wagner Lotta von Sydow Harald Aigner Sergiu Netotea Sabine Brugière Lars Sjögren Myriam Ferro Adrian Clarke Christiane Funk 《Plant, cell & environment》2016,39(11):2530-2544
The membrane‐integrated metalloprotease FtsH11 of Arabidopsis thaliana is proposed to be dual‐targeted to mitochondria and chloroplasts. A bleached phenotype was observed in ftsh11 grown at long days or continuous light, pointing to disturbances in the chloroplast. Within the chloroplast, FtsH11 was found to be located exclusively in the envelope. Two chloroplast‐located proteins of unknown function (Tic22‐like protein and YGGT‐A) showed significantly higher abundance in envelope membranes and intact chloroplasts of ftsh11 and therefore qualify as potential substrates for the FtsH11 protease. No proteomic changes were observed in the mitochondria of 6‐week‐old ftsh11 compared with wild type, and FtsH11 was not immunodetected in these organelles. The abundance of plastidic proteins, especially of photosynthetic proteins, was altered even during standard growth conditions in total leaves of ftsh11. At continuous light, the amount of photosystem I decreased relative to photosystem II, accompanied by a drastic change of the chloroplast morphology and a drop of non‐photochemical quenching. FtsH11 is crucial for chloroplast structure and function during growth in prolonged photoperiod. 相似文献
994.
Aim This study aims to elucidate the phylogeography of the arctic‐alpine annual Comastoma tenellum (Rottb.) Toyok. (Gentianaceae) and to unravel the history of its immigration into the Alps. Location Although samples from Alaska and Central Asia were also included, our study focusses on Europe, especially on the Alps. Methods We applied amplified fragment length polymorphism (AFLP) fingerprinting on 37 populations (162 individuals) of C. tenellum and analysed the results phenetically. Results As C. tenellum is mainly inbreeding, there is typically little to no intrapopulational genetic variation. Two populations from Alaska and Altai are strongly separated from all other accessions. The majority of the populations from the Alps group together with high bootstrap support. They fall into an unsupported Alps I group (northwards of Gran Paradiso) and a well‐supported Alps II group (south‐western Alps). The remaining European populations form a weakly‐supported branch constituting accessions from the Carpathians, Scandinavia and two populations from the Eastern Alps. Main conclusions Comastoma tenellum reached the Alps at least twice. The first immigration event resulted in a lineage that is clearly separated from the other European accessions. The immigration must have occurred well before the last glaciation because this lineage shows further phylogeographical structuring into two groups (Alps II in the south‐western Alps and Alps I in the rest of the Alps). This pattern is presumably due to isolation in different glacial refugia. In addition to the old immigration event, the species reached the Alps in recent times either from Scandinavia or from the Carpathians via long‐distance dispersal. These immigrations resulted in (at least) two populations that are spatially small and poor in individuals. 相似文献
995.
Nina??ster?sEmail author Leti?van Bodegom-Vos Krysia?Dziedzic Tuva?Moseng Eline?Aas ?yvor?Andreassen Ibrahim?Mdala B?rd?Natvig Jan?Harald?R?tterud Unni-Berit?Schjervheim Thea?Vliet?Vlieland K?re?Birger?Hagen 《Implementation science : IS》2016,10(1):165
Background
Previous research indicates that people with osteoarthritis (OA) are not receiving the recommended and optimal treatment. Based on international treatment recommendations for hip and knee OA and previous research, the SAMBA model for integrated OA care in Norwegian primary health care has been developed. The model includes physiotherapist (PT) led patient OA education sessions and an exercise programme lasting 8–12 weeks. This study aims to assess the effectiveness, feasibility, and costs of a tailored strategy to implement the SAMBA model.Methods/design
A cluster randomized controlled trial with stepped wedge design including an effect, process, and cost evaluation will be conducted in six municipalities (clusters) in Norway. The municipalities will be randomized for time of crossover from current usual care to the implementation of the SAMBA model by a tailored strategy. The tailored strategy includes interactive workshops for general practitioners (GPs) and PTs in primary care covering the SAMBA model for integrated OA care, educational material, educational outreach visits, feedback, and reminder material. Outcomes will be measured at the patient, GP, and PT levels using self-report, semi-structured interviews, and register based data. The primary outcome measure is patient-reported quality of care (OsteoArthritis Quality Indicator questionnaire) at 6-month follow-up. Secondary outcomes include referrals to PT, imaging, and referrals to the orthopaedic surgeon as well as participants’ treatment satisfaction, symptoms, physical activity level, body weight, and self-reported and measured lower limb function. The actual exposure to the tailor made implementation strategy and user experiences will be measured in a process evaluation. In the economic evaluation, the difference in costs of usual OA care and the SAMBA model for integrated OA care will be compared with the difference in health outcomes and reported by the incremental cost-effectiveness ratio (ICER).Discussion
The results from the present study will add to the current knowledge on tailored strategies, which aims to improve the uptake of evidence-based OA care recommendations and improve the quality of OA care in primary health care. The new knowledge can be used in national and international initiatives designed to improve the quality of OA care.Trial registration
ClinicalTrials.gov NCT02333656996.
Exposure of postmitotic growing and non-growing cells of the unicellular green alga Micrasterias denticulata to different UV-B cut-off wavelengths together with simulated sunlight in a sun simulator has revealed a marked resistence of the algae against strong irradiation. While down to a cut-off wavelength of 284 nm irradiated during the most sensitive stage of cell development chloroplast ultrastructure remains unaffected, severe changes in arrangement and structure of stroma and grana thylakoids occur only at the lowest cut-off wavelengths of 280 and 275 nm. The structural alterations end up in a more or less complete desintegration of grana and stroma thylakoids with the remaining membraneous structures appearing in negative staining thus indicating drastic changes in membrane composition. Photosynthetic activity determined by chlorophyll fluorescence (ratio of variable to maximal fluorescence) and oxygen evolution responded more sensitively to UV-B irradiation. With decreasing UV cut-off wavelengths and prolonged incubation a decrease of photochemistry of PS II occured reaching its lowest values after 60 min at 275 and 280 nm. Oxygen production was even maintained under strong UV irradiation with a cut-off wavelenght of 275 nm up to 15 min. With prolonged UV-B treatment any activity was lost. HPLC separations of pigments exhibited the appearance of break-down products (mainly derivatives of chl b and chl a) with decreasing cut-off wavelength and increasing exposure time. The xanthophyll cycle pigments seemed to be unaffected at least for an irradiation period of 60 to 90 min at low UV cut-offs. Possible mechanisms of UV stress avoidance or protection are discussed with regard to the varying altitudes of the natural habitats of the algae. 相似文献
997.
Wierckx N Koopman F Ruijssenaars HJ de Winde JH 《Applied microbiology and biotechnology》2011,92(6):1095-1105
Microbial metabolism of furanic compounds, especially furfural and 5-hydroxymethylfurfural (HMF), is rapidly gaining interest
in the scientific community. This interest can largely be attributed to the occurrence of toxic furanic aldehydes in lignocellulosic
hydrolysates. However, these compounds are also widespread in nature and in human processed foods, and are produced in industry.
Although several microorganisms are known to degrade furanic compounds, the variety of species is limited mostly to Gram-negative
aerobic bacteria, with a few notable exceptions. Furanic aldehydes are highly toxic to microorganisms, which have evolved
a wide variety of defense mechanisms, such as the oxidation and/or reduction to the furanic alcohol and acid forms. These
oxidation/reduction reactions constitute the initial steps of the biological pathways for furfural and HMF degradation. Furfural
degradation proceeds via 2-furoic acid, which is metabolized to the primary intermediate 2-oxoglutarate. HMF is converted,
via 2,5-furandicarboxylic acid, into 2-furoic acid. The enzymes in these HMF/furfural degradation pathways are encoded by
eight hmf genes, organized in two distinct clusters in Cupriavidus basilensis HMF14. The organization of the five genes of the furfural degradation cluster is highly conserved among microorganisms capable
of degrading furfural, while the three genes constituting the initial HMF degradation route are organized in a highly diverse
manner. The genetic and biochemical characterization of the microbial metabolism of furanic compounds holds great promises
for industrial applications such as the biodetoxifcation of lignocellulosic hydrolysates and the production of value-added
compounds such as 2,5-furandicarboxylic acid. 相似文献
998.
Proteinaceous, hair-like appendages known as fimbriae or pili commonly extend from the surface of prokaryotic cells and serve important functions such as cell adhesion, biofilm formation, motility and DNA transfer. Here we show that a novel group of archaea from cold, sulphidic springs has developed cell surface appendages of an unexpectedly high complexity with a well-defined base-to-top organization. It represents a new class of filamentous cell appendages, for which the term 'hamus' is proposed. Each archaeal cell is surrounded by a halo of about 100 hami, which mediate strong adhesion of the cells to surfaces of different chemical composition. The hami are mainly composed of 120 kDa subunits and remained stable in a broad temperature and pH range (0-70 degrees C; 0.5-11.5). Electron microscopy and cryo-electron tomography revealed that the hamus filament possesses a helical basic structure. At periodic distances, three prickles emanate from the filament, giving it the character of industrially produced barbwire. At its distal end the hami carry a tripartite, barbed grappling hook (60 nm in diameter). The architecture of this molecular hook is reminiscent of man-made fishhooks, grapples and anchors. It appears that nature has developed a perfect mechanical nano-tool in the course of biological evolution, which also might prove useful in the field of nanobiotechnology. 相似文献
999.
Understanding the impact of anthropogenic threats, such as light pollution, on biodiversity is necessary to establish effective guidelines to protect diminishing wildlife. In this study, we examined the effect of artificial light at night (ALAN) on the roosting behaviour of Chimney Swifts Chaetura pelagica, a highly threatened migratory bird species that lives commensally with humans, where it often breeds and roosts in artificial structures such as chimneys. Although Chimney Swifts are known to use time of sunset in combination with temperature, wind and season to coordinate roost entry, we predicted that high ALAN exposure would override these natural cues and lead to a delayed entry compared with sites with less light pollution. To test this, we examined the effects of ALAN on the start and end times of entry to 21 roosting sites located along a light pollution gradient in New Jersey and the New York Metropolitan area. We found that ALAN was a significant predictor of roosting entry time, with birds entering later in sites with more light pollution. While Chimney Swifts initiated roosting earlier in the summer months compared with the autumn, this effect was absent in areas with high light pollution. These findings highlight the need to determine the causes and consequences of light pollution effects. 相似文献
1000.