1,823 research outputs found
A 128-point Multi-Path SC FFT Architecture
This paper presents a new radix-2^k multi-path FFT architecture, named MSC
FFT, which is based on a single-path radix-2 serial commutator (SC) FFT
architecture. The proposed multi-path architecture has a very high hardware
utilization that results in a small chip area, while providing high throughput.
In addition, the adoption of radix-2^k FFT algorithms allows for simplifying
the rotators even further. It is achieved by optimizing the structure of the
processing element (PE). The implemented architecture is a 128-point 4-parallel
multi-path SC FFT using 90 nm process. Its area and power consumption at 250
MHz are only 0.167 mm2 and 14.81 mW, respectively. Compared with existing
works, the proposed design reduces significantly the chip rea and the power
consumption, while providing high throughput.Comment: Conference paper, ISCAS 2020, 5 page
Dose pre-hospital laryngeal mask airway use has a survival benefit in non-shockable cardiac arrest?
Background. Whether pre-hospital laryngeal mask airway (LMA) use poses a survival benefit and should be approved as
routine airway management in non-shockable cardiac arrest is of major concern. The present study examined the effectiveness
of LMA, in comparison to other pre-hospital airway management on individuals who have experienced non-shockable
cardiac arrest.
Methods. Adult patients who experienced non-shockable cardiac arrest with activation of the emergency medical service
(EMS) made up our study cohort in Taoyuan, Taiwan. The data were abstracted from EMS records and cardiac arrest registration
protocols.
Results. Among the 1912 enrolled patients, most received LMA insertion (72.4%), 108 (5.6%) bag-valve-mask (BVM) ventilation,
376 (19.7%) high-flow oxygen non-rebreather facemask, and only 44 (2.3%) received endotracheal tube intubation
(ETI). With regard to survival to discharge, no significant differences in prevalence were evident among the groups: 2.8% of
oxygen facial mask, 1.1% of BVM, 2.1% of LMA, and 4.5% of the ETI group survived to discharge (p = 0.314). In comparison
to oxygen facial mask use, different types of airway management remained unassociated with survival to discharge after
adjusting for variables by logistic regression analysis (BVM: 95% confidence interval [CI], 0.079 â 1.639 [p = 0.186]; LMA:
95% CI, 0.220â2.487 [p = 0.627]; ETI: 95% CI, 0.325â17.820 [p = 0.390]). The results of Hosmer-Lemeshow goodness-of-fit
test of logistic regression model revealed good calibration.
Conclusions. Pre-hospital LMA use was not associated with additional survival to discharge compared with facial oxygen
mask, BVM, or ETI following non-shockable cardiac arrest
Rate adaptation for 802.11 multiuser mimo networks
In multiuser MIMO (MU-MIMO) networks, the optimal bit rate of a user is highly dynamic and changes from one packet to the next. This breaks traditional bit rate adaptation algorithms, which rely on recent history to predict the best bit rate for the next packet. To address this problem, we introduce TurboRate, a rate adaptation scheme for MU-MIMO LANs. TurboRate shows that clients in a MU-MIMO LAN can adapt their bit rate on a per-packet basis if each client learns two variables: its SNR when it transmits alone to the access point, and the direction along which its signal is received at the AP. TurboRate also shows that each client can compute these two variables passively without exchanging control frames with the access point. A TurboRate client then annotates its packets with these variables to enable other clients to pick the optimal bit rate and transmit concurrently to the AP. A prototype implementation in USRP-N200 shows that traditional rate adaptation does not deliver the gains of MU-MIMO WLANs, and can interact negatively with MU-MIMO, leading to low throughput. In contrast, enabling MU-MIMO with TurboRate provides a mean throughput gain of 1.7x and 2.3x, for 2-antenna and 3-antenna APs respectively.National Science Council (China) (contract No. NSC 100-2221-E-001-005-MY2)National Science Foundation (U.S.) (NSF Grant CNS-1117194
NEUROPROTECTIVE EFFECT OF TERMINALIA CHEBULA EXTRACTS AND ELLAGIC ACID IN PC12 CELLS
Alzheimerâs disease (AD) is one of the most prevalent severe neurological disorders afflicting our aged population. The study was to determine neuroprotective effects of the Terminalia chebula extracts and ellagic acid by using beta-amyloid25-35 (Ab25-35)-induced cell cytotoxicity in undifferentiated rat pheochromocytoma (PC12) cellular model. The methanolic and water extracts of T. chebula and ellagic acid exhibited the strongest neuroprotective activity against Ab25-35-induced undifferentiated PC12 cell deaths at 0.5â5.0 ug/ml. The ellagic acid also exhibited the partial neuroprotective activity against H2O2-induced undifferentiated PC12 cell deaths at 0.5â5.0 ug/ml. The methanolic and water extracts of T. chebula and ellagic acid protected undifferentiated PC12 cells from the damaging effects of Ab25-35 in several ways: (1) by securing cell viability; (2) by suppressing reactive oxygen species production; and (3) by eliminating calcium ion influx. The T. chebula extracts maybe represent a promising plant-source for medicine in the application of the treatment of AD. Further investigation of the ellagic acid is necessary to verify the neuroprotective efficacy and mechanisms in vivo
Risk of Vertebral Fracture in Patients Diagnosed with a Depressive Disorder: A Nationwide Population-Based Cohort Study
OBJECTIVE: Previous studies have reported that depression may play a crucial role in the occurrence of vertebral fractures. However, a clear correlation between depressive disorders and osteoporotic fractures has not been established. We explored the association between depressive disorders and subsequent new-onset vertebral fractures. Additionally, we aimed to identify the potential risk factors for vertebral fracture in patients with a depressive disorder. METHODS: We studied patients listed in the Taiwan National Health Insurance Research Database who were diagnosed with a depressive disorder by a psychiatrist. The comparison cohort consisted of age- and sex-matched patients without a depressive disorder. The incidence rate and hazard ratios of subsequent vertebral fracture were evaluated. We used Cox regression analysis to evaluate the risk of vertebral fracture among patients with a depressive disorder. RESULTS: The total number of patients with and without a depressive disorder was 44,812. The incidence risk ratio (IRR) between these 2 cohorts indicated that depressive disorder patients had a higher risk of developing a subsequent vertebral fracture (IRR=1.41, 95% confidence interval [CI]=1.26-1.57,
Dilated Dense U-Net for Infant Hippocampus Subfield Segmentation
Accurate and automatic segmentation of infant hippocampal subfields from magnetic resonance (MR) images is an important step for studying memory related infant neurological diseases. However, existing hippocampal subfield segmentation methods were generally designed based on adult subjects, and would compromise performance when applied to infant subjects due to insufficient tissue contrast and fast changing structural patterns of early hippocampal development. In this paper, we propose a new fully convolutional network (FCN) for infant hippocampal subfield segmentation by embedding the dilated dense network in the U-net, namely DUnet. The embedded dilated dense network can generate multi-scale features while keeping high spatial resolution, which is useful in fusing the low-level features in the contracting path with the high-level features in the expanding path. To further improve the performance, we group every pair of convolutional layers with one residual connection in the DUnet, and obtain the Residual DUnet (ResDUnet). Experimental results show that our proposed DUnet and ResDUnet improve the average Dice coefficient by 2.1 and 2.5% for infant hippocampal subfield segmentation, respectively, when compared with the classic 3D U-net. The results also demonstrate that our methods outperform other state-of-the-art methods
Associations between Tumor Vascularity, Vascular Endothelial Growth Factor Expression and PET/MRI Radiomic Signatures in Primary Clear-CellâRenal-Cell-Carcinoma: Proof-of-Concept Study
Studies have shown that tumor angiogenesis is an essential process for tumor growth, proliferation and metastasis. Also, tumor angiogenesis is an important prognostic factor of clear cell renal cell carcinoma (ccRCC), as well as a factor in guiding treatment with antiangiogenic agents. Here, we attempted to find the associations between tumor angiogenesis and radiomic imaging features from PET/MRI. Specifically, sparse canonical correlation analysis was conducted on 3 feature datasets (i.e., radiomic imaging features, tumor microvascular density (MVD), and vascular endothelial growth factor (VEGF) expression) from 9 patients with primary ccRCC. In order to overcome the potential bias of intratumoral heterogeneity of angiogenesis, this study investigated the relationship between regional expressions of angiogenesis and VEGF, and localized radiomic features from different parts within the tumors. Our study highlighted the significant strong correlations between radiomic features and MVD, and also demonstrated that the spatiotemporal features extracted from DCE-MRI provided stronger radiomic correlation to MVD than the textural features extracted from Dixon sequences and FDG PET. Furthermore, PET/MRI, which takes advantage of the combined functional and structural information, had higher radiomics correlation to MVD than solely utilizing PET or MRI alone
Decadal changes in the mid-depth water mass dynamic of the Northeastern Atlantic margin (Bay of Biscay)
The lithium/magnesium (Li/Mg) molar ratios, radiocarbon measurements (?14C) and Nd-isotopic composition (eNd) of the aragonite skeleton of a branching cold-water coral (CWC) species Madrepora oculata collected alive in the Bay of Biscay at ~691 m water depth were investigated to reconstruct a robust record of the mid-depth water mass dynamics between 1950 and 1990 AD. Temperature estimates based on the skeletons Li/Mg molar ratios reveal small decadal changes of about 1 °C at thermocline depth synchronous to and of similar amplitude as surface temperature anomalies. ?14C measurements shows quasi-decadal oscillations of 15â° around pre-bomb ?14C average value of -59±6â° and post-bomb ?14C of -12±6â°, which most likely reflect decadal changes of water mass exchange across the thermocline. The coral eNd values remain in narrow ranges of -11.9 to -10.2, similar to the isotopic composition of East North Atlantic Central Water, but show highest values in the late 1950s, and early 1960s, 1970s, and 1980s. The punctuated changes of the coral Nd-isotopic composition may thus reflect periods of particular enhanced advection of temperate intermediate water (mid-depth Subpolar Gyre/Mediterranean Sea Water). Altogether, our robust multi-proxy record provides new evidence that Northern Hemisphere atmospheric variability (such as, North Atlantic Oscillation and East Atlantic pattern) drives changes not only in the thermocline but also in the mid-depth water-mass advection patterns in the Northeastern Atlantic margin. However, the interannual variability of our record remains to be tested
Critical Role of Cysteine-Rich Protein 61 in Mediating the Activation of Renal Fibroblasts
ObjectiveTo explore the expression of cysteine-rich protein 61 (Cyr61) in ischemic renal fibrosis and the role of Cyr61 in mediating the activation of renal fibroblasts.Methods(1) The rat model of renal fibrosis was established after ischemia-reperfusion acute renal injury (IR-AKI). We detected the renal function by biochemical test, evaluated the fibrosis by Masson staining, and detected the expression of Cyr61 by western blotting. (2) Bioinformatics technique was adopted to analyze the expression of Cyr61 in activated renal fibroblasts. (3) Normal rat kidney fibroblast cells (NRK-49F cells) with over-expression of Cyr61 (Cyr61+) and low-expression of it (Cyr61--) were established by plasmid transfection. Then part of the cells were activated by TGF-ÎČ1 and NRK-49F cells were divided into control group, activated group, Cyr61+/Cyr61-- group and Cyr61+/Cyr61-- activated group. The expression of Cyr61 and fibrosis related factors (Col1α1, Col3α1, MMP9, and MMP13) were ascertained by PCR and western blotting. Cell proliferation was discovered by CCK8 method, cell cycle was analyzed by flow cytometry, and the transcription of cell senescence related factors (P53, P21, Rb, and P16) were ascertained by PCR method.Results(1) In the process of fibrosis after IR-AKI, the area of collagen fiber was most obviously at AKI 1W, while the Cyr61 protein was at the lowest level at AKI 1W. (2) Gene chip analysis showed that the expression of Cyr61 was decreased in renal fibroblasts after IR. (3) Compared with control group, Cyr61+ group expressed less Col1α1 or Col3α1, as well as more MMP9 and MMP13. At the same time, the proliferation of Cyr61+ group decreased and cells in G1 phases increased with more transcription of P53, P21, and Rb (all P < 0.05). Compared with activated group, the results of Cyr61+ activated group were similar to the above. The above effects of low expression group were just the opposite. In addition, there was no difference in the transcription of P16 among these groups (P > 0.05).ConclusionCyr61 may not only inhibit the fibrotic phenotype of fibroblasts, but may also inhibit proliferation by promoting fibroblasts arrest in G1 phase through the P53/P21/Rb interrelated cell senescence pathway, subsequently affecting the process of ischemic renal fibrosis
Chromosome segregation in Archaea : SegAâ and SegBâDNA complex structures provide insights into segrosome assembly
Genome segregation is a vital process in all organisms. Chromosome partitioning remains obscure in Archaea, the third domain of life. Here, we investigated the SegAB system from Sulfolobus solfataricus. SegA is a ParA Walker-type ATPase and SegB is a site-specific DNA-binding protein. We determined the structures of both proteins and those of SegAâDNA and SegBâDNA complexes. The SegA structure revealed an atypical, novel non-sandwich dimer that binds DNA either in the presence or in the absence of ATP. The SegB structure disclosed a ribbonâhelixâhelix motif through which the protein binds DNA site specifically. The association of multiple interacting SegB dimers with the DNA results in a higher order chromatin-like structure. The unstructured SegB N-terminus plays an essential catalytic role in stimulating SegA ATPase activity and an architectural regulatory role in segrosome (SegAâSegBâDNA) formation. Electron microscopy results also provide a compact ring-like segrosome structure related to chromosome organization. These findings contribute a novel mechanistic perspective on archaeal chromosome segregation
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