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881.
We report on the development of a new environmental simulation chamber coupled with an in situ continuous wave cavity ring-down spectrometer operating in the near IR (~1.5 μm). The first application reported in this paper dealt with the chemical mechanism of UV photolysis of methyl nitrite (CH(3)ONO) in air. HONO has been detected for the first time and shown to be formed in the OH + CH(3)ONO reaction. A dense spectrum of cis-HONO absorption lines has been observed near 1.5 μm, in agreement with a previous study (Guilmot et al.). CH(2)O has been measured as primary product with good sensitivity and time resolution. In contrast to Zhao et al., we did not detect any NO(2) absorption features in this wavelength range. Calibration experiments provided very low NO(2) absorption cross sections in this region (~10(-25) cm(2)), leading to conclude that NO(2) cannot be observed in this wavelength range in the presence of equal amounts of CH(2)O. 相似文献
882.
Eva Johansson Petter Oscarson Waheeb K Heneen Tomas Lundborg 《Journal of the science of food and agriculture》1994,64(3):305-313
The concentration and composition of storage proteins in the developing kernels of five different wheat cultivars were investigated. The plants were grown in solution culture under strictly controlled conditions in climatic chambers and with long-term limitation of external nitrogen availability. Thus, by growing these cultivars under the same defined treatments, reliable differences in the storage protein development could be determined. The total protein concentration was assayed using an automatic nitrogen analyser. The storage protein composition was examined by acidic polyacrylamide gel electrophoresis and sodium dodecyl sulphate polyacrylamide gel electrophoresis from 6 to 58 days after anthesis. The results showed that, in all stages of plant development, the ranking of the cultivars as to the storage protein concentration was the same as for mature field-grown kernels. The differences in the storage protein concentration between the cultivars could not be explained by differences in protein composition. The start of storage protein formation during plant development did not differ between the tested cultivars, as determined by the electrophoresis pattern. The differences in the storage protein concentration between cultivars most likely depends on the relative balance between starch and nitrogen deposition in the grain, during the whole grain filling period. 相似文献
883.
Jorge Rico-Fontalvo Gustavo Aroca Jose Cabrales Rodrigo Daza-Arnedo Tomas Ynez-Rodríguez María Cristina Martínez-vila Isabella Uparella-Gulfo María Raad-Sarabia 《International journal of molecular sciences》2022,23(15)
The inflammatory component of diabetic kidney disease has become of great interest in recent years, with genetic and epigenetic variants playing a fundamental role in the initiation and progression of the disease. Cells of the innate immune system play a major role in the pathogenesis of diabetic kidney disease, with a lesser contribution from the adaptive immune cells. Other components such as the complement system also play a role, as well as specific cytokines and chemokines. The inflammatory component of diabetic kidney disease is of great interest and is an active research field, with the hope to find potential innovative therapeutic targets. 相似文献
884.
Mohammed S. I. Mansour Karina Malmros Ulrich Mager Kajsa Ericson Lindquist Kim Hejny Benjamin Holmgren Tomas Seidal Annika Dejmek Katalin Dobra Maria Planck Hans Brunnstrm 《International journal of molecular sciences》2022,23(9)
Immune checkpoint inhibitors (ICI) targeting programmed cell death-1 or its ligand (PD-L1) have improved outcomes in non-small cell lung cancer (NSCLC). High tumor PD-L1 expression, detected by immunohistochemistry (IHC) typically on formalin-fixed paraffin-embedded (FFPE) histological specimens, is linked to better response. Following our previous investigation on PD-L1 in cytological samples, the aim of this study was to further explore the potential impacts of various clinicopathological and molecular factors on PD-L1 expression. Two retrospective NSCLC cohorts of 1131 and 651 specimens, respectively, were investigated for PD-L1 expression (<1%/1–49%/≥50%), sample type, sample site, histological type, and oncogenic driver status. In both cohorts, PD-L1 was positive (≥1%) in 55% of the cases. Adenocarcinomas exhibited lower PD-L1 expression than squamous cell carcinomas (p < 0.0001), while there was no difference between sample types, tumor locations, or between the two cohorts in multivariate analysis (all p ≥ 0.28). Mutational status correlated significantly with PD-L1 expression (p < 0.0001), with the highest expression for KRAS-mutated cases, the lowest for EGFR-mutated, and the KRAS/EGFR wild-type cases in between. There was no difference in PD-L1 levels between different prevalent KRAS mutations (all p ≥ 0.44), while mucinous KRAS-mutated adenocarcinomas exhibited much lower PD-L1 expression than non-mucinous (p < 0.0001). Our data indicate that cytological and histological specimens are comparable for PD-L1 evaluation. Given the impact of KRAS mutations and the mucinous growth pattern on PD-L1 expression, these factors should be further investigated in studies on ICI response. 相似文献
885.
Martin Tomas Valtchev Petko Roux Louis-Romain 《Knowledge and Information Systems》2023,65(8):3295-3335
Knowledge and Information Systems - Mining frequent itemsets (FIs) from data streams is a challenging task due to the limited resources available w.r.t. the typically large size of the result and... 相似文献
886.
887.
Carmen C. Mayorga-Martinez Marketa Castoralova Jaroslav Zelenka Tomas Ruml Martin Pumera 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(6):2205047
Bovine mastitis produced by Staphylococcus aureus (S. aureus) causes major problems in milk production due to the staphylococcal enterotoxins produced by this bacterium. These enterotoxins are stable and cannot be eradicated easily by common hygienic procedures once they are formed in dairy products. Here, magnetic microrobots (MagRobots) are developed based on paramagnetic hybrid microstructures loaded with IgG from rabbit serum that can bind and isolate S. aureus from milk in a concentration of 3.42 104 CFU g−1 (allowable minimum level established by the United States Food and Drug Administration, FDA). Protein A, which is present on the cell wall of S. aureus, selectively binds IgG from rabbit serum and loads the bacteria onto the surface of the MagRobots. The selective isolation of S. aureus is confirmed using a mixed suspension of S. aureus and Escherichia coli (E. coli). Moreover, this fuel-free system based on magnetic robots does not affect the natural milk microbiota or add any toxic compound resulting from fuel catalysis. This system can be used to isolate and transport efficiently S. aureus and discriminate it from nontarget bacteria for subsequent identification. Finally, this system can be scaled up for industrial use in food production. 相似文献
888.
Ahmad Jaradat Chengji Zhang Sanket Shashikant Sutar Nannan Shan Shuxi Wang Sachin Kumar Singh Taimin Yang Khagesh Kumar Kartikey Sharma Shahriar Namvar Ahmadiparidari Alireza Tomas Rojas Vikas Berry Jordi Cabana-Jimenez Zhehao Huang Arunkumar Subramanian Anh T. Ngo Larry A. Curtiss Amin Salehi-khojin 《Advanced functional materials》2023,33(21):2300814
Lithium-air batteries based on CO2 reactant (Li–CO2) have recently been of interest because it has been found that reversible Li/CO2 electrochemistry is feasible. In this study, a new medium-entropy cathode catalyst, (NbTa)0.5BiS3, that enables the reversible electrochemistry to operate at high rates is presented. This medium entropy cathode catalyst is combined with an ionic liquid-based electrolyte blend to give a Li–CO2 battery that operates at high current density of 5000 mA g−1 and capacity of 5000 mAh g−1 for up to 125 cycles, far exceeding reported values in the literature for this type of battery. The higher rate performance is believed to be due to the greater stability of the multi-element (NbTa)0.5BiS3 catalyst because of its higher entropy compared to previously used catalysts with a smaller number of elements with lower entropies. Evidence for this comes from computational studies giving very low surface energies (high surface stability) for (NbTa)0.5BiS3 and transmission electron microscopystudies showing the structure being retained after cycling. In addition, the calculations indicate that Nb-terminated surface promotes Li–CO2 electrochemistry resulting in Li2CO3 and carbon formation, consistent with the products found in the cell. These results open new direction to design and develop high-performance Li–CO2 batteries. 相似文献
889.
Lucas Gonzalez Pierre Lafleur Tomas Lozano Ana B. Morales Ricardo Garcia Marisela Angeles Francisco Rodriguez Saul Sanchez 《Polymer Composites》2014,35(1):1-9
The effects of stearic acid treatment on the crystallization, morphology, thermal, and mechanical properties of polypropylene (PP)/montmorillonite (Mm) nanocomposites were investigated. Stearic acid was used as a new surface modifier for Mm, and also small amounts of this acid were used as a new interface modifier. Nanocomposites containing 1.5, 2.5, 5, and 10% in weight of the unmodified and modified Mm were prepared by melt blending. The tensile and impact properties of nanocomposites were evaluated. Wide‐angle X‐ray diffraction was used to study both the generated PP β crystals and the dispersion state of the nanocomposites. Differential scanning calorimeter was used to detect the melting and crystallization behavior of the samples. The toughness of some nanocomposites was higher than the pure PP. β phase of PP was observed with the addition of Mm. Stearic acid favored the dispersion of the nanocomposites when used as interface modifier. Nanocomposites with better dispersion exhibited crystallization temperatures similar to pure PP. POLYM. COMPOS., 35:1–9, 2014. © 2013 Society of Plastics Engineers 相似文献