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71.

One of the most important functionalities for the dual connectivity (DC) technology in non-stand-alone (NSA) fifth generation (5G) networks is the flow control algorithm (FCA), which has the role of correctly splitting the data traffic of users in DC. However, delays in backhaul links and the time between two executions of the FCA may limit the effectiveness of the split ratios computed by the FCA in situations where unexpected channel variations or an increase in the traffic load happen. In this context, we propose a heuristic mechanism where the user assists the FCA in performing a faster and finer adjustment of the bearer split ratios. The proposed mechanism works based on a single scalar value and can be combined with any existing FCA. Besides the adjustment of the bearer split ratios, the proposed mechanism may also trigger handover/disconnection when it detects problems in one of the user connections, which is a novel feature that is not present in existing solutions. Simulations demonstrate the gains provided by the proposed mechanism in terms of user satisfaction, total system rate and user throughput.

  相似文献   
72.
The quality of natural coffee produced in Brazil is quite variable. Fruits at different stages of maturation can be found on the same plant, and unripe fruits are naturally present during the harvest. The pulping of ripe fruits can be effectively used to improve the quality of the coffee, as the ripe fruits will be separated from the unripe fruits; however, the presence of a portion of unripe fruit (with lower quality) in the processing is unavoidable. The wet processing of immature coffee fruit appears to be a potential way of improving its quality. According to the coffee processing used post-harvest, changes were observed in the levels of free amino acids in immature coffee beans. Among the amino acids present, asparagine is the primary amino acid found in unripe coffee beans. Asparagine produces acrylamide, a potentially harmful substance generated during the course of the Maillard reaction. In this study, amino acids in immature coffee beans were analysed using reversed-phase chromatography and ultraviolet detection after the derivatisation with phenylisothiocyanate. The amino acid profiles of the immature coffee beans demonstrated that asparagine is present at more significant levels when immature coffee fruits were processed via dry processing, as compared to wet processing.  相似文献   
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A goethite-based catalyst was evaluated using in-situ X-ray absorption near-edge structure (XANES) spectroscopy during methane oxidation under increasing reaction temperature. Determination of rank by median absolute deviation (DRMAD), evolving factor analysis (EFA), and multivariate curve resolution (MCR) were used to detect the species present in the catalyst during the reaction and determine their concentration profiles and their pure spectra. The reactants and reaction products were monitored on-line by mass spectrometer. The goethite-based catalyst was active for methane oxidation, with CO(2) and H(2)O as the main products. DRMAD and EFA were useful to determine the number of chemical species present in the catalyst structure during reactions. The catalyst presented phase transition during the reaction from goethite to maghemite according to XANES spectra determined by MCR. On the other hand, it was verified that the catalyst presented phase transition from goethite to wüstite in the process in the absence of the oxidant (O(2)).  相似文献   
76.
We have used proteome analysis of derivatives of R. leguminosarum biovar trifolii strain ANU843, cured of indigenous plasmids by a direct selection system, to investigate plasmid-encoded functions. Under the conditions used, the plasmid-encoded gene products contributed to only a small proportion of the 2000 proteins visualised in the two-dimensional (2-D) protein map of strain ANU843. The level of synthesis of thirty-nine proteins was affected after curing of either plasmid a, c or e. The differences observed upon plasmid curing included: protein loss, up/down-regulation of specific proteins and novel synthesis of some proteins. This suggests that a complex interplay between the cured plasmid and the remaining replicons is occurring. Twenty-two proteins appeared to be absent in the cured strains and these presumably are encoded by plasmid genes. Of these, a small heat shock protein, a cold shock protein, a hypothetical YTFG-29.7 kDa protein, and the alpha and beta subunits of the electron transfer flavoprotein were identified by N-terminal microsequencing and predicted to be encoded by plasmid e. Four of the sequenced proteins putatively encoded on plasmid e and two encoded on plasmid c were novel. In addition, curing of plasmid e and c consistently decreased the levels of 3-isopropylmalate dehydratase and malate dehydrogenase, respectively, suggesting that levels of these proteins may be influenced by plasmid-encoded functions. A protein with homology to 4-oxalocrotonate tautomerase, which is involved in the biodegradation of phenolic compounds, was found to be newly synthesised in the strain cured of plasmid e. Proteome analysis provides a sensitive tool to examine the functional organisation of the Rhizobium genome and the global gene interactions which occur between the different replicons.  相似文献   
77.
Rod-like projections on the surface of Chlamydia trachomatis have been studied by a combination of computer image analysis and electron microscopy. The rods, c. 60-80 A in diameter and c. 500 A in length, were found on the surface of prokaryocells of C. trachomatis inserted in the cytoplasmic membrane through a ring-like structure in the outer membrane. The rod-like structures were found at all stages of the life cycle, even in very small elementary bodies (EBs) of C. trachomatis and in vesicles < 0.2 micron. Computer image analysis of isolated rods indicated that they comprise helically arranged subunits with a periodicity of c. 50 A. From their localisation and distribution, these structures may be related to the proliferation, or to the infectivity, of chlamydiae.  相似文献   
78.
Irradiation of B16 pigmented melanoma subcutaneously transplanted in C57 mice with a single 650 mJ pulse (10 ns) of 1064 nm light from a Q-switched Nd: YAG laser caused instantaneous bleaching of the pigmented tissue. Visual and histological examination of the resulting gray-colored tumor revealed the breakdown of melanosomes with no detectable alteration of the normal and tumor-overlying skin. Histological examination of the irradiated tumor showed some degree of vascular damage; the depth of the photodamage was not affected by the successive delivery of three consecutive light pulses. The bleached tumor grew at a modestly slower rate but the high-peak-power (HPP) laser treatment did not affect the tumor concentration of a photodynamic sensitizer Si(i.v.)-naphthalocyanine (isoBO-SiNc) intravenously injected 24 h before Nd:YAG irradiation. Treatment of the B16 pigmented melanoma by photodynamic therapy (PDT: 1 mg/kg isoBO-SiNc, 300 mW/cm2, 520 J/cm2) from a 774 nm diode laser immediately after the 1064 nm irradiation resulted in a 16 day delay of tumor regrowth, which was markedly longer than the delay (ca 6 days) obtained after PDT under identical conditions without the preirradiation. Thus, pretreatment of pigmented tumors with HPP 1064 nm light appears to enhance their susceptibility to conventional PDT. The tumor response was further enhanced by repeating the combined HPP/PDT treatment at an interval of 10 days (regrowth delay: 27 days), as well as by applying hyperthermia immediately after HPP/PDT (regrowth delay: ca 34 days).  相似文献   
79.
Adrenal lipomas are extremely rarely occurring benign tumors being hormonally inactive. The patient described in this report underwent surgical excision of an adrenal lipoma because of the associated hypertension. The blood pressure decreased postoperatively to normal levels. This case report and the review of the literature consider diagnosis and therapy of the adrenal lipomas.  相似文献   
80.
We report the enzymatic synthesis of α‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranoside and α‐D ‐glucopyranosyl‐(1→3)‐α‐L ‐rhamnopyranoside by using a wild‐type transglucosidase in combination with glucoamylase and glucose oxidase. It was shown that Bacillus circulans 251 cyclodextrin glucanotransferase (CGTase, EC 2.1.4.19) can efficiently couple an α‐L ‐rhamnosyl acceptor to a maltodextrin molecule with an α‐(1→4) linkage, albeit in mixture with the α‐(1→3) regioisomer, thus giving two glucosylated acceptors in a single reaction. Optimisation of the CGTase coupling reaction with β‐cyclodextrin as the donor substrate and methyl or allyl α‐L ‐rhamnopyranoside as acceptors resulted in good conversion yields (42–70 %) with adjustable glycosylation regioselectivity. Moreover, the efficient chemical conversion of the products of CGTase‐mediated cis‐glucosylation into protected building blocks (previously used in the synthesis of O‐antigen fragments of several Shigella flexneri serotypes) was substantiated. These novel chemoenzymatic strategies towards useful, convenient intermediates in the synthesis of S. flexneri serotypes 2a and 3a oligosaccharides might find applications in developments towards synthetic carbohydrate‐based vaccine candidates against bacillary dysentery.  相似文献   
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