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1.
《Cell reports》2020,30(7):2065-2074.e4
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J. Stronkhorst 《Aquatic Ecology》1988,22(2):127-134
The error inin vivo
14C incubator measurements of primary production in the Eastern Scheldt when neutral density filters were used and the error obtained when no account was taken of the spectral changes in submarine irradiance that occur with increasing depth, were evaluated theoretically. By multiplying the photosynthetic action spectra of two marine algae by calculated irradiance in the euphotic layer using Kd and Kd() respectively, the gross primary production P[Ed(400–700)] and P[Ed()] was computed. In the green-brown waters of the Eastern Scheldt estuary the use of neutral density filters was sufficient to simulate the underwater light conditions. In clear waters it can cause an overestimation of the gross production. 相似文献
5.
Gérald Chouinard Charles Vincent Stuart B. Hill Bernard Panneton 《Journal of Insect Behavior》1992,5(3):385-394
From 12 to 19 May 1987, during Morspur apple bloom, 21 radioactively labeled (65
Zn) adult plum curculios, Conotrachelus nenuphar (Herbst), were released within a field cage containing four dwarf apple trees and located three times a day. A technique was developed for quickly obtaining (x, y, z)coordinates of location for adults foraging within apple trees. Cyclic patterns of behavior were detected using spectral analysis procedures. Over 70% of plum curculios exhibited diel periodicity with respect to activity and rate of movement, 36% exhibited such periodicity with respect to presence in the trees, and 27% with respect to movements from the center to the periphery of the canopy. Presence in fruit clusters, height in the trees, and movements along east-west and north-south axes showed little or no periodicity. Factors triggering cyclic behavior and practical implications of the results are discussed. 相似文献
6.
Béla Böddi Birgitta McEwen Margareta Ryberg Christer Sundqvist 《Physiologia plantarum》1994,92(1):160-170
Low-temperature fluorescence emission spectra of 6.5-day-old dark-grown epicotyls of pea ( Pisum sativum ) revealed the presence of protochlorophyll(ide). The upper part of the epicotyl contained 30% of the protochlorophyll(ide) content per fresh weight found in pea leaves, whereas the lower part contained 3%. Three discrete spectral forms of protochlorophyll(ide) were clearly distinguished after Gaussian deconvolution of fluorescence excitation and emission spectra. Adding the satellite bands of the Qy(0-0) transitions (the emission vibrational (Emv) bands with correlated amplitudes, gave the following delineation: Ex439–Em629–Emv684, Ex447–Em636–Emv700 and Ex456–Em650–Emv728. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunodetection of whole tissue extracts of the epicotyl indicated the presence of NADPH-protochlorophyllide oxidoreductase (EC 1.3.1.33). Electron micrographs showed prolamellar bodies in at most 11 % of the plastid profiles of the epicotyl cells. These prolamellar bodies were smaller, and many of them showed less regular structure than those of the leaves. Taken together, the results indicate that the protochlorophyll(ide) in epicotyls is arranged in a different way than in leaves. 相似文献
7.
Tomohiro Ito Toui Yoshioka Hiromori Shimabukuro Gregory N. Nishihara Hikaru Endo Ryuta Terada 《Phycological Research》2023,71(1):25-36
The effect of temperature, light-spectrum, desiccation and salinity gradients on the photosynthesis of a Japanese subtidal brown alga, Sargassum macrocarpum (Fucales), was determined using a pulse amplitude modulation-chlorophyll fluorometer and dissolved oxygen sensors. Temperature responses of the maximum (Fv/Fm in darkness) and effective (ΔF/Fm′ at 50 μmol photons m−2 s−1; = ΦPSII) quantum yields during 6-day culture (4–36°C) remained high at 12–28°C, but decreased at higher temperatures. Nevertheless, ΔF/Fm′ also dropped at temperatures below 8°C, suggesting light sensitivity under chilling temperatures because Fv/Fm remained high. Photosynthesis–irradiance responses at 24°C under red (660 nm), green (525 nm), blue (450 nm) and white light (metal halide lamp) showed that maximum net photosynthesis under blue and white light was greater than under red and green light, indicating the sensitivity and photosynthetic availability of blue light in the subtidal light environment. In the desiccation experiment, samples under aerial exposure of up to 8 h under dim-light at 24°C and 50% humidity showed that ΔF/Fm′ quickly declined after more than 45 min of emersion; furthermore, ΔF/Fm′ also failed to recover to initial levels even after 1 day of rehydration in seawater. Under the emersion state, the ΔF/Fm′ remained high when the relative water content (RWC) was greater than 50%; in contrast, it quickly dropped when the RWC was less than 50%. When the RWC was reduced below 50%, ΔF/Fm′ did not return to initial levels, regardless of subsequent re-hydration, suggesting a low capacity of photosynthesis to recover from desiccation. The stenohaline response of photosynthesis under 3-day culture is evident, given that ΔF/Fm′ declined when salinity was beyond 20–40 psu. Adaptation to subtidal environments in temperate waters of Japan can be linked to these traits. 相似文献
8.
A thorough analysis of glass containing Eu2O3 and Dy2O3, or Eu2O3, Dy2O3, and CuO melted together with nanodiamond powder was pursued based on measurements of optical absorption, photoluminescence (PL) emission and excitation spectra, and colorimetry. Nanodiamond facilitated the stabilization of Cu+ and Eu2+ ions with blue-emitting characteristics that, along with yellow-emitting Dy3+ and red-emitting Eu3+ led to the white light-emitting glass. Novel intensity notations implemented in intensity-based spectral ratios, and difference intensity correlation analysis were proposed for the assessment of PL properties. The chromaticity and correlated colour temperature of the emission were ultimately investigated as a two-parametric problem based on: (1) the different ionic components; and (2) the various excitation wavelengths employed. The optical analysis approach adds to the characterization methods to further fundamental understanding and provide helpful analytical tools for designing materials for tunable white light-emitting devices. 相似文献
9.
Thang V. Pham Vinh V. Nguyen Duong Vu Alex A. Henneman Robin A. Richardson Sander R. Piersma Connie R. Jimenez 《Proteomics》2023,23(7-8):2200041
Accurate retention time (RT) prediction is important for spectral library-based analysis in data-independent acquisition mass spectrometry-based proteomics. The deep learning approach has demonstrated superior performance over traditional machine learning methods for this purpose. The transformer architecture is a recent development in deep learning that delivers state-of-the-art performance in many fields such as natural language processing, computer vision, and biology. We assess the performance of the transformer architecture for RT prediction using datasets from five deep learning models Prosit, DeepDIA, AutoRT, DeepPhospho, and AlphaPeptDeep. The experimental results on holdout datasets and independent datasets exhibit state-of-the-art performance of the transformer architecture. The software and evaluation datasets are publicly available for future development in the field. 相似文献
10.
Sharon L. Gursky 《International journal of primatology》1995,16(1):843-853
I present quantitative and qualitative data on infant caretaking behaviors collected during a preliminary field study of spectral
tarsiers (Tarsius spectrum),in a northern Sulawesi rain forest. The primary goal of the study is to identify the basic pattern of infant care in this
species. I studied tarsiers at Tangkoko-Dua Saudara Nature Reserve in Sulawesi, Indonesia, from May to July 1992. I observed
two infants, from two groups for a total of 96 hr using focal follows. During individual focal follows, ranging from 20 min
to 6 hr, I recorded behaviors at 5-min intervals. I also recorded distances of group members relative to the infant at 5-min
intervals. I subsampled the data at 35-min intervals to control for statistical autocorrelation between data points. Infants
were alone between 40 and 50% of the time. The two subadults were more frequently in proximity to the infant than the adult
males, the nonmatemal adult female, or the mothers were. This pattern of the subadults maintaining proximity to the infant
continued when the mothers were absent. These results suggest that subadults may be guarding or babysitting infants. It is
also possible that subadults are not traveling as far from the sleeping site as adults do and are therefore more likely to
be found in association with the infant. 相似文献