239 research outputs found
Performance Evaluation of Distributed-Antenna Communications Systems Using Beam-Hopping
No full textDigital beamforming (DBF) techniques are capable of improving the performance of communications systems significantly. However, if the transmitted signals are conflicted with strong interference, especially, in the direction of the transmitted beams , these directional jamming signals will severely degrade the system performance. In order to efficiently mitigate the interference of the directional jammers, in this contribution a beam-hopping (BH) communications scheme is proposed. In the proposed BH communications scheme, only one pair of the beams is used for transmission and it hops from one to the next according to an assigned BH pattern. In this contribution a range of expressions in terms of the average SINR performance have been derived, when both the uplink and downlink are considered. The average SINR performance of the proposed BH scheme and that of the conventional single-beam (SB) as well as multiple-beam (MB) assisted beam-processing schemes have been investigated. Our analysis and results show that the proposed BH scheme is capable of efficiently combating the directional jamming, with the aid of utilizing the directional gain of the beams generated by both the transmitter and the receiver. Furthermore, the BH scheme is capable of reducing the intercept probability of the communications. Therefore, the proposed BH scheme is suitable for communications, when several distributed antenna arrays are available around a mobile
Virtual Drug Design
No full textThis eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contac
Virtual Drug Design
No full textThis eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contac
Pharmacovigilance study of the frequency of gastrointestinal ulceration reports associated with immune checkpoint inhibitors: insights from the FDA adverse event reporting system
Get PDFBackgroundImmune checkpoint inhibitors (ICIs) have revolutionized the treatment landscape for cancer, yet they are linked to immune-related adverse events (AEs), one of which includes gastrointestinal ulceration (GU). The objective of this study was to evaluate the reporting frequency of GU reported in connection with ICIs by utilizing data from the United States (U.S.) Food and Drug Administration Adverse Event Reporting System (FAERS).Materials and methodsAEs pertaining to GU attributed to ICIs were extracted from the U.S. FAERS database for the time frame spanning from the fourth quarter of 2018 to the fourth quarter of 2024. A disproportionality analysis was performed employing the reporting odds ratio (ROR) and information component (IC), accompanied by 95% confidence intervals (95% CI). Beyond the disproportionality analysis, this investigation also examined gender disparities and the latency period for the onset of gastrointestinal AEs related to ICIs.ResultsA total of 1,415 adverse event reports regarding GU linked to ICIs as the primary suspect drug were collected. The occurrence of GU attributed to ICIs was observed to be more prevalent among males and older individuals. The principal countries reporting these events were Japan, the United States, and Germany, with Japan notably contributing the highest number of reports for Nivolumab and Pembrolizumab. A significant association was observed between the drugs Ipilimumab (ROR: 3.73 [3.14–4.44], IC: 1.89), Pembrolizumab (ROR: 3.08 [2.83–3.35], IC: 1.60), Atezolizumab (ROR: 4.10 [3.67–4.58], IC: 2.02), Nivolumab (ROR: 2.45 [2.23–2.69], IC: 1.28) and reports of GU. Conversely, Cemiplimab (ROR: 1.06 [0.55–2.05], IC: 0.09) did not exhibit a significant correlation. Among patients administered Pembrolizumab, the reporting frequency of intestinal perforation in females was considerably greater than that in males, presenting the most robust signal strength (ROR = 1.98 [1.28–3.05], P < 0.01).ConclusionThis study presents the most current real-world evidence regarding the safety profile of ICIs therapy in relation to GU, highlighting variations among different ICIs and between genders. It is imperative for healthcare providers to maintain heightened awareness of potential GU adverse events associated with ICIs and to implement timely preventive or therapeutic interventions to enhance the safety of ICIs in clinical practice
One step preparation of pure tau-MnAl phase with high magnetization using strip casting method
No full textFerromagnetic phase of Mn-Al exhibits great potential in the rare-earth free permanent magnetic materials due to its high magnetocrystalline anisotropy, high magnetization, high Curie temperature and low cost. In this work, the strip casting technique was applied to prepare MnAl magnetic phase. X-ray diffraction and energy dispersive X-ray analyses indicate that the as-prepared Mn54Al46 strip sample consists of pure tau-MnAl magnetic phase. It is found that the composition of Mn54Al46 is suitable to prepare tau-MnAl phase during the strip casting process. The Mn54Al46 strip sample synthesized through the strip casting exhibits a fairly high magnetization of 114 emu/g under a field of 5 T, while the coercivity of iHc = 2.8 kOe, magnetization of M-5T = 63.9 emu/g at room temperature can be obtained for Mn54Al46 powder sample. This preparation method can produce a large amount of tau-phase MnAl alloy and promote mass industrialized production. (C) 2017 Author(s)
Identification and characterization of microRNAs from the bovine adipose tissue and mammary gland
No full textAbstractWe report the identification of bovine miRNAs by cloning small RNAs from adipose tissue and the mammary gland. Fifty-nine distinct miRNAs were identified, five of them were not homologous to known mammalian miRNAs, and many of them had 3′ and/or 5′ end variants. Ribonuclease protection assays indicated that miR-23a and miR-24, whose genes are closely located on the same chromosome, were co-expressed in different tissues. The assays also suggested a role for several miRNAs in the mammary gland and a role for miR-133, a previously known skeletal and cardiac muscle-specific miRNA, in the rumen, an organ unique to the ruminant
Survey of Lightweight Block Cipher
No full textWith the rapid development of information technology,human beings are entering the era of ubiquitous connectivity,where billions of Internet of Things(IoT) devices are connected to the network.The continuous growth of network attacks targeting user privacy and the network environment has made it crucial to ensure the information security of IoT devices.Due to the limited computational capabilities,battery capacity,and memory resources of IoT devices,conventional block cipher algorithms are not suitable for IoT devices that require low latency and low power consumption,lightweight block cipher algorithms have emerged to address these challenges.This paper provides an overview of the research status and progress of lightweight block cipher algorithms,and categorizes them into six types according to their structure.It comprehensively compares and analyzes the hardware and software implementations of lightweight block cipher algorithms based on multidimensional evaluation criteria.Furthermore,it explores the security,resource consumption,and performance aspects in-depth.Finally,this paper discusses the future research directions of lightweight block cipher algorithms
Endocrinology
No full textThe transcription factor signal transducer and activator of transcription (STAT)-5 mediates GH stimulation of IGF-I gene expression in the liver. Previous studies suggested that STAT5 might exert this effect by binding to an IGF-I intron 2 region and a distal 5' -flanking region each containing two STAT5 binding sites. Here we report the identification of three additional chromosomal regions containing a total of five putative STAT5 binding sites that may mediate GH-induced STAT5 activation of IGF-I gene expression in the mouse liver. By comparing an 170-kb mouse genomic DNA containing the IGF-I gene with the corresponding human sequence, we identified 19 putative STAT5 binding sites that bear the consensus sequence of STAT5 binding site and are conserved across the two species. Chromatin immunoprecipitation assays indicated that five chromosomal regions containing a total of nine of the 19 putative STAT5 binding sites were bound by STAT5 in the mouse liver in response to GH administration and that these bindings preceded or coincided with GH-increased IGF-I gene transcription. Two of the five chromosomal regions correspond to those previously identified in other species, and the three new chromosomal regions that contain a total of five putative STAT5 binding sites are IGF-I intron 3 regions located at least 26 kb from the transcription start site. Gelshift assays confirmed the binding of the five new putative STAT5 binding sites as well as three of the four previously identified STAT5 binding sites to GH-activated STAT5 from the mouse liver. Cotransfection analyses indicated that, although each of the five chromosomal regions was able to mediate STAT5 activation of reporter gene expression, together they mediated greater STAT5 activation of reporter gene expression in response to GH. Overall, these results suggest that GH-induced STAT5 activation of IGF-I gene expression in the mouse liver might be collectively mediated by at least eight STAT5 binding sites located located in distal intronic and 5' -flanking regions of the IGF-I gene
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