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21.
This paper intends to present a summary of the technical issues arising in the exploitation of the 60 GHz mm-wave band for mobile and personal communications. The most significant applications proposed so far are surveyed, with particular emphasis placed on recent experimentation about millimeter-wave propagation for road/railway transportation as well as indoor scenarios. As a case study, the capacity of a (micro-)cellular Code Division Multiple Access (CDMA) network in the 60-GHz band is also evaluated in detail.  相似文献   
22.
Recently, a recombinant SARS-CoV-2 lineage, XD, emerged that harbors a spike gene that is largely derived from the Omicron variant BA.1 in the genetic background of the Delta variant. This finding raised concerns that the recombinant virus might exhibit altered biological properties as compared to the parental viruses and might pose an elevated threat to human health. Here, using pseudotyped particles, we show that ACE2 binding and cell tropism of XD mimics that of BA.1. Further, XD and BA.1 displayed comparable sensitivity to neutralization by antibodies induced upon vaccination with BNT162b2/Comirnaty (BNT) or BNT vaccination followed by breakthrough infection. Our findings reveal important biological commonalities between XD and Omicron BA.1 host cell entry and its inhibition by antibodies.  相似文献   
23.
American trypanosomiasis is a worldwide health problem that requires attention due to ineffective treatment options. We evaluated n-butyl and isobutyl quinoxaline-7-carboxylate 1,4-di-N-oxide derivatives against trypomastigotes of the Trypanosoma cruzi strains NINOA and INC-5. An in silico analysis of the interactions of 1,4-di-N-oxide on the active site of trypanothione reductase (TR) and an enzyme inhibition study was carried out. The n-butyl series compound identified as T-150 had the best trypanocidal activity against T. cruzi trypomastigotes, with a 13% TR inhibition at 44 μM. The derivative T-147 behaved as a mixed inhibitor with Ki and Ki’ inhibition constants of 11.4 and 60.8 µM, respectively. This finding is comparable to the TR inhibitor mepacrine (Ki = 19 µM).  相似文献   
24.
In this paper we investigate the performance of a combined estimation/equalization technique for the mobile radio channel, assuming a GSM-recommended transmission format (narrowband TDMA with midamble, recommendation 5.04) and MSK modulation scheme. Channel estimation is performed via correlation of the received signal with a suitably modulated replica of the transmitted midamble. Equalization is then obtained by means of a maximum likelihood sequence estimation (MLSE) scheme in the form of a so-called Viterbi equalizer. Our analysis provides theoretical results concerning the bit error rate (BER) attained by the receiver for a given stationary multipath channel model. Simulation results are also presented in order to integrate and validate the theory.  相似文献   
25.
MHOMS: high-speed ACM modem for satellite applications   总被引:1,自引:0,他引:1  
This article presents the novel FPGA-based 1 Gb/s near-Shannon-limit ACM modem developed within the MHOMS program with particular focus on the advanced modem algorithm solutions devised. A number of powerful FEC schemes have been analyzed as possible candidates for the MHOMS modem, and the final selection is justified in terms of the best tradeoff between complexity and performance. State-of-the-art modulation and demodulation algorithms are also presented, including nonlinearity dynamic precompensation techniques and innovative synchronization strategies required by the selected powerful modulation and coding schemes. Overall modem performances are also shown for a variety of spectral efficiencies.  相似文献   
26.
Reduction of energy in foods by eliminating sugar, combined with an increase in fiber, frequently results in products with sensory characteristics that cannot be compared with standard counterparts. This study analyzed the response of young educated consumers (n = 704) on standard or reduced-sugar vanilla yogurt enriched with inulin or with inulin combined with a grain mixture, a milled mixture of flakes, or a combination of grains and milled flakes. On a nine-point hedonic scale, mean acceptance was 6.4 and 6.8 for yogurt with 112 g kg?1 and 160 g kg?1 sugar, respectively. It was concluded from acceptance data and from results obtained by just-about-right rating that adapting the flavoring concentration might be an appropriate tool to mask sugar reduction. In yogurt with visible fiber, it is mainly the size of incorporated fiber that should be considered in product optimization. In these products, sugar content significantly affects acceptance.  相似文献   
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28.
Resident democracy as a special form of participatory democratic set-up is fundamental in the understanding, and self-understanding, of the non-profit housing sector in Denmark. Through a case study, the paper explores how resident democracy is perceived and narrated between residents and employees at a housing association. The study indicates that the meta-story of democracy is disconnected from practice and the lived lives of residents. Three analytical tensions structure the analysis, which relate to the conditions for realizing the democratic ideal embedded in the structure of the sector. The tensions are related to representative versus participatory democracy; collectivity versus individuality; and service versus welfare. The tensions elucidate how resident democracy is squeezed between different logics, which result in an ambiguous setting for practising democracy. Based on the results, the article discusses conditions for prospective democracy in the Danish non-profit housing sector.  相似文献   
29.
    
Zusammenfassung Im Gewebeextrakt und Preßsaft der Brust- und Schenkelmuskulatur des Huhns sowie der Brustmuskulatur von Pute, Gans, Ente und Taube wurde die Aktivität der Aspartat-Aminotransferase (GOT; E.C.2.6.1.1.) und der Alanin-Aminotransferase (GPT; E.C.2.6.1.2.) bestimmt. Die Gesamt-GOT-und GPT-Aktivität war in der dunklen Schenkelmuskulatur des Huhnes signifikant höher als in der hellen Brustmuskulatur. Eine ähnliche Beziehung zwischen Myoglobingehalt und Transaminase-Aktivität bestand auch bei den anderen Geflügelarten. Hühner- und Putenmuskeln wiesen die niedrigsten, Taubenmuskeln die höchsten Transaminase-Aktivitäten auf. Die gesamte GPT-Aktivität in den Muskeln von Huhn und Pute betrug etwa ein Hundertstel der gesamten GOT-Aktivität; in den Muskeln der übrigen Geflügelarten machte die GPT-Aktivität etwa ein Zehntel der GOT-Aktivität aus.In der Muskulatur aller untersuchten Geflügelarten ließen sich durch Elektrophorese zwei GOT-Isozyme nachweisen. Ein Isozym (GOT S ) befand sich im Sarkoplasma, das andere Isozym (GOT M ) war in den Mitochondrien lokalisiert. Die GOT M -Aktivität in Brust- und Schenkelmuskel des Huhns betrug durchschnittlich 65% der gesamten GOT-Aktivität. Bei den übrigen Geflügelarten schien mit steigendem Myoglobingehalt des Brustmuskels die relative GOT M -Aktivität zuzunehmen.Während siebentägiger postmortaler Lagerung von Brust- und Schenkelmuskulatur des Huhns bei 4° C trat keine wesentliche Änderung der gesamten GOT-Aktivität ein. Die niedrige relative GOT M -Aktivität im Muskelpreßsaft nahm während der Lagerung des Muskels nur wenig zu; eine Schädigung der Mitochondrienmembranen tritt daher während der Reifung von Hühnerfleisch nicht ein.
Aminotransferases in the skeletal muscles of poultry
Summary The activity of aspartate aminotransferase (GOT; E.C.2.6.1.1.) and alanine amino-transferase (GPT; E.C.2.6.1.2.) in the breast and thigh muscle of chicken and in the breast muscle of turkey, goose, duck, and pigeon was determined. The total GOT and GPT activity of the red thigh muscle of chicken was significantly higher than that of the white breast muscle. A similar relation between myoglobin content and transaminase activity in breast muscle was found for the other species of poultry. Chicken and turkey muscles showed the lowest, pigeon muscles the highest transaminase activities. The total GPT activity of chicken and turkey muscles was about one-hundredth of the total GOT activity; the GPT activity in muscles of the other species was about one-tenth of the total GOT activity.In the extract of the muscles of all species two GOT isozymes could be demonstrated after electrophoretic separation. One isozyme (GOT M ) is localized within the mitochondria, the other isozym (GOTs) was found in the sarcoplasma. About 65% of the total GOT activity in breast and thigh muscles of chicken was due to the activity of the mitochondrial isozyme. In the breast muscles of the other species, higher relative GOT M activity was found in the muscles with high myoglobin content than in those with low myoglobin content.There was no remarkable change in the total GOT activity of the muscle extract during storage of chicken breast and thigh muscles at +4° C for seven days post mortem. The small relative GOT M activity of the muscle press juice remained almost unchanged during post-mortem storage of muscle tissue indicating that there is no desintegration of the mitochondrial membranes during aging of chicken meat.


Fräulein H. Sauer danken wir für ihre fleißige und gewissenhafte Mitarbeit.  相似文献   
30.
This paper presents the design and the main performance results of a single-ASIC implementation of the recently proposed extended complex-valued blind anchored interference-mitigating detector (EC-BAID) for code division multiple access (CDMA) transmission. Such a detector, which exhibits a remarkable robustness to multiple access interference, operates in blind mode, i.e., it only requires knowledge of the timing of the wanted user's signature code, and it is therefore very well-suited for integration into handheld single-user terminal demodulators. The implementation of the interference-mitigating detector is based on a patented optimized architecture which leads, in 0.25-μm CMOS technology, to a roughly 25 Kgate plus 23-Kbit RAM single-chip ASIC supporting chip rates up to 4 Mchip/s with a maximum internal clock frequency of 32.768 MHz. The main design drivers are thoroughly discussed, and the relevant performance results are compared to the theoretical behavior. A possible extension to multirate CDMA systems adopting orthogonal variable spreading factor (OVSF) sequences is also addressed  相似文献   
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