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61.
Autotrophic nitrogen removal systems have been implemented at full‐scale and provide an efficient way for nitrogen removal from industrial and urban wastewaters. Our study present qualitative and quantitative analysis of archaeal and bacterial amoA genes and Candidatus Brocadiales bacteria analyzed in six full‐scale autotrophic nitrogen removal bioreactors. The results showed that ammonium oxidizing bacteria (AOB) were detected in all bioreactors. However, ammonium oxidizing archaea (AOA) were detected only in the non‐aerated technologies. Conversely, different Candidatus Brocadiales phylotypes appeared due to differences in influent wastewater composition and hydraulic retention time (HRT). In the same terms multivariate redundancy analysis confirmed that AOA was positively correlated with temperature, ammonium concentration and low HRT. However, AOB population was positively correlated with pH, temperature, and dissolved oxygen concentration. Our data suggested a correlation between the microorganisms involved in the nitrogen removal performance and the operational conditions in the different full‐scale bioreactors. © 2017 American Institute of Chemical Engineers AIChE J, 64: 457–467, 2018  相似文献   
62.
The increasing demand for the use of sustainable materials in industrial applications has created an urge to develop technologies that enable the use of biopolymers such as cellulose for the improvement of properties of commercial products. In this study, the potential of the silyl functionalized cellulose nanofibrils (CNF) as a reinforcing additive for the water‐ and solvent‐based two‐component polyurethane (PU) lacquer coatings was evaluated. The addition of the silylated CNF improved the abrasion resistance, strength, and elasticity of the PU coatings. When using the silylated CNF as an additive, the adhesion of the PU coatings was retained. The oxygen permeation rate of the silylated CNF films was strongly influenced by the nature of the solvent. The silylated CNF showed potential as a reinforcing additive even at low loadings in the two‐component PU lacquers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44801.  相似文献   
63.
The core 1 structure is the major constituent of mucin-type O-glycans, which are added via glycosylation—a posttranslational modification present on membrane-bound and secretory proteins. Core 1 β1,3-galactosyltransferase (C1galt1), an enzyme that synthesizes the core 1 structure, requires Cosmc, a C1galt1-specific molecular chaperone, for its enzymatic activity. Since Cosmc-knockout mice exhibit embryonic lethality, the biological role of core 1-derived O-glycans in the adult stage is not fully understood. We generated ubiquitous and inducible CAGCre-ERTM/Cosmc-knockout (iCAG-Cos) mice to investigate the physiological function of core 1-derived O-glycans. The iCAG-Cos mice exhibited a global loss of core 1-derived O-glycans, high mortality, and showed a drastic reduction in weights of the thymus, adipose tissue, and pancreas 10 days after Cosmc deletion. They also exhibited leukocytopenia, thrombocytopenia, severe acute pancreatitis, and atrophy of white and brown adipose tissue, as well as spontaneous gastric ulcers and severe renal dysfunction, which were considered the causes underlying the high mortality of the iCAG-Cos mice. Serological analysis indicated the iCAG-Cos mice have lower blood glucose and total blood protein levels and higher triglyceride, high-density lipoprotein, and total cholesterol levels than the controls. These data demonstrate the importance of core 1-derived O-glycans for homeostatic maintenance in adult mice.  相似文献   
64.
Ultra-reliable low-latency communications (URLLC) is a new feature to be considered for the fifth generation (5G) cellular systems. This feature is essential for the support of envisioned mission-critical applications, particularly in the realm of machine-type communications. These applications require that the messages, which are generally short-length packets, to be exchanged between a source and a destination with the high level of reliability and within a short period of time. The characteristics of URLLC do not fit directly in the conventional communication models. For instance, most of the existing communication models are developed considering moderate levels of reliability, neglecting the small effects of the feedback errors. However, even such small errors cannot be ignored for URLLC. This paper proposes a communication model for URLLC considering the reliabilities of both data and control channels. Then, the optimal and sub-optimal resource allocations are derived. We show that the proposed sub-optimal resource allocations have lower computational complexities with a negligible performance degradations compared to that of the optimal solutions. The results reveal that the possibility of performing only one retransmission can significantly reduce the required radio resources needed for data delivery compared to the case of performing a single transmission round.  相似文献   
65.
The purpose of this research was to study the prevalence of ectopic eruption of the first permanent molars and possible etiologic factors. A group of 4,232 Thai students, from 6 to 9 years old, was examined. The prevalence of ectopic eruption of the first permanent molars in the subjects was 0.75%. Both the severity of the ectopic eruption and the amount of root resorption on the second primary molars were more pronounced in the maxilla than in the mandible. The important etiologic factors were the eruption path of the first permanent molars relative to reference lines and the size of the mandibular second primary molars. The amount of proximal caries did not seem to affect the prevalence of ectopic eruption.  相似文献   
66.
Satoyoshi syndrome is a rare neurological disorder of unknown etiology characterized by progressive muscle spasms, alopecia, diarrhea and skeletal abnormalities. We here describe a 25-year-old man who developed symptoms similar to neuroleptic malignant syndrome (NMS). He began to have the clinical characteristics of Satoyoshi syndrome at the age of 12 years. He was admitted to hospitals many times with painful muscle spasms and pyrexia in the early stage of the disease. He received steroid pulse therapy and oral prednisone at the age of 19, the extent and frequency of the spells being reduced thereafter. He was admitted to our hospital due to recurrence of his usual muscle spasms. He was treated with midazolam intravenously to relieve severe muscle ache, pain in the left shoulder, and insomnia. About 90 minutes later, he became comatose, with the following manifestations: hyperthermia, low blood pressure, tachycardia, profuse perspiration, acute respiratory failure, and ensuing cardiac arrest. He developed rhabdomyolysis, acute renal failure, hepatic damage, and diffuse intravascular coagulation. Serum creatine kinase level was elevated to 306,910 IU. He died of multiple organ failure 13 days after admission. His symptoms resembled NMS and malignant hyperthermia (MH). None of patients with Satoyoshi syndrome accompanied by NMS or MH have been reported. It remains to be clarified whether midazolam administration induces NMS in Satoyoshi syndrome. Nevertheless, careful attention should be paid when one administers midazolam to patients with this syndrome.  相似文献   
67.
68.
Balanced fairness is a new resource sharing concept recently introduced by Bonald and Proutière. We extend the use of this notion to wireless multi-hop networks, e.g. ad hoc networks, where the link capacities at the flow level are not fixed but depend on lower layer issues such as scheduling and interference. Utilizing this extension we present the theoretical framework for flow level performance analysis of elastic traffic in the setting, assuming that the wireless bandwidth resources are subject to linear constraints. We discuss how different physical and access layer configurations can be described by the linear constraint model and devise an efficient computational scheme for solving the system. The concepts and the computational scheme are illustrated by a number of examples.  相似文献   
69.
Interference is disruptive to the operation of wireless sensor networks (WSNs) in unlicensed bands as wireless systems proliferate on the spectrum. The design of a spectrum sharing scheme for WSNs to enable coexistence with geographically collocated heterogeneous wireless systems having multiple parallel interfering channels is a persistent challenge. In this context, interference identification and channel ranking in terms of spectrum access opportunities are addressed in this paper. The goal is to develop a low complexity channel ranking algorithm from channel energy measurements at sensors when a packet-reception-ratio to signal-to-interference-and-noise-ratio (PRR-SINR) interference model is unavailable at network initialization phase. The interference characterizing estimators, temporal occupancy and strength level of a channel, are proposed for interference identification. The effectiveness of the estimators is tested on a sensor platform at 2.4 GHz ISM band under interference from WLAN. Subsequently, the impact of the interference estimators on a channel quality from a receiver perspective is determined with a decision theoretic approach. The estimators are weighted according to their influence on the fitness of a channel and channel ranking is established. The proposed channel ranking achieves a significant gain over heuristic channel ranking (HCR) and gives an accurate interference profile of the channels.  相似文献   
70.
The magnitude, duration and oscillation of cellular signalling pathway responses are often limited by negative feedback loops, defined as an ‘activator-induced inhibitor’ regulatory motif. Within the NFκB signalling pathway, a key negative feedback regulator is IκBα. We show here that, contrary to current understanding, NFκB-inducible expression is not sufficient for providing effective negative feedback. We then employ computational simulations of NFκB signalling to identify IκBα molecular properties that are critical for proper negative feedback control and test the resulting predictions in biochemical and single-cell live-imaging studies. We identified nuclear import and nuclear export of IκBα and the IκBα–NFκB complex, as well as the free IκBα half-life, as key determinants of post-induction repression of NFκB and the potential for subsequent reactivation. Our work emphasizes that negative feedback is an emergent systems property determined by multiple molecular and biophysical properties in addition to the required ‘activator-induced inhibitor’ relationship.  相似文献   
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