367 research outputs found
Analysis on Human Blockage Path Loss and Shadow Fading in Millimeter-Wave Band
Millimeter-wave (Mm-w) is the trend of communication development in the future; users who carry mobile communication equipment could be blocked by others in a crowded population environment. Based on Shooting and Bouncing Ray (SBR) method and setting up different orientation receivers (RX), population density, and people fabric property at 28 GHz and 38 GHz, simulating experimental scene similar to station square by Wireless Insite software, we use least square method to do linear-regression analysis for path loss and build path loss model. The result shows that the path loss index has a certain change in the different frequency, orientation receivers, population density, and people fabric. The path loss index of RouteC1 and RouteA2 has an obvious change in the central transmitter (TX). Each route shadow fading obeys Gaussian distribution whose mean is 0. This paper’s result has a theoretical guiding for designing the communication system in a crowded population environment
NK cell exhaustion in the tumor microenvironment
Natural killer (NK) cells kill mutant cells through death receptors and cytotoxic granules, playing an essential role in controlling cancer progression. However, in the tumor microenvironment (TME), NK cells frequently exhibit an exhausted status, which impairs their immunosurveillance function and contributes to tumor immune evasion. Emerging studies are ongoing to reveal the properties and mechanisms of NK cell exhaustion in the TME. In this review, we will briefly introduce the maturation, localization, homeostasis, and cytotoxicity of NK cells. We will then summarize the current understanding of the main mechanisms underlying NK cell exhaustion in the TME in four aspects: dysregulation of inhibitory and activating signaling, tumor cell-derived factors, immunosuppressive cells, and metabolism and exhaustion. We will also discuss the therapeutic approaches currently being developed to reverse NK cell exhaustion and enhance NK cell cytotoxicity in the TME
Clinical report about the effectiveness of andriol, tamoxifen, vitamin A and lecithin on low acrosome
BackgroundAcrosin is the most important proteolytic enzyme in fertilization, acrosome dysfunction affects fertilization. Recently, our group found that the treatment of andriol, tamoxifen, vitamin A and lecithin helped to improve acrosome function.AimsTo assess the effectiveness of andriol, tamoxifen, vitamin A and lecithin on low acrosome.MethodsSeventy-eight infertility males in my hospital were enrolled. Kenedy test was used to test acrosome function. Andriol, tamoxifen, vitamin A and lecithin were used for one to four months.ResultsSperm concentration (t=5.05, P=0.000) raised while seminal volume (t=1.93, P=0.057), normal morphology (t=0.24, P=0.811) and progressive sperm (t=2.14, P=0.036) did not show statistical difference after treatment. Acrosin was (37.62±11.07)μIU/106 sperm before treatment and raised to (52.68±15.68)μIU/106 sperm after treatment and showed statistical difference (t=8.18, P=0.00). In all the 78 males, the acrosin of seven men (11 per cent) bellowed after treatment while the acrosin of 71 males (91 per cent) raised and ten couples (13 per cent) got pregnant.ConclusionThe combined treatment of andriol, tamoxifen, vitamin A and lecithin were effective on low acrosin
Bearing health assessment based on chaotic characteristics
Abstract. Vibration signals extracted from rotating parts of machinery carry a lot of useful information about the condition of operating machine. Due to the strong non-linear, complex and non-stationary characteristics of vibration signals from working bearings, an accurate and reliable health assessment method for bearing is necessary. This paper proposes to utilize the selected chaotic characteristics of vibration signal for health assessment of a bearing by using self-organizing map (SOM). Both Grassberger-Procaccia algorithm and Takens' theory are employed to calculate the characteristic vector which includes three chaotic characteristics, such as correlation dimension, largest Lyapunov exponent and Kolmogorov entropy. After that, SOM is used to map the three corresponding characteristics into a confidence value (CV) which represents the health state of the bearing. Finally, a case study based on vibration datasets of a group of testing bearings was conducted to demonstrate that the proposed method can reliably assess the health state of bearing
Effectiveness of two kind of medicine on non-obstructive azoospermia
ObjectiveTo assess the effectiveness of medicine on non-obstructive azoospermia (NOA). Cases32 male patients were enrolled from March 2012 to March 2016, with age range of 23–41 years old and infertility time of 1–3 years.Methods According to “WHO Human Semen Detection and Processing Experiment Manual";;;;;; fifth edition, semen routine was based on manual detection and serum hormones based on chemiluminescence detection, semen volume, sperm density, forward moving sperm ratio. If sperm was detected in semen for more than two consecutive times, the treatment was considered effective and was included into the statistical analysis. The detection parameters took the first test data and the last test data. Treatment Andriol and tamoxifen were used for idiopathic NOA while aescuven forte and aspirin used for NOA with varicocele (including two varicocelectomy). The time was four months.ResultsOf the 32 patients, 13 underwent testicular biopsy, pathological results showed six patients (46 per cent) with hypospermatogenesis, five patients (39 per cent) with maturation arrest, and two patients (15 per cent) with sertoli cell syndrome. Nine patients (28 per cent) had varicocele; two patients (6 per cent) underwent surgical treatment. After treatment, sperm was detected in 20 patients (63 per cent), seven of them (22 per cent) had detectable sperm in semen after one month of treatment; five (19 per cent) had sperm after two months of treatment; eight (25 per cent) had sperm after three months of treatment. Among the 23 patients with idiopathic azoospermia, 13 patients had detectable sperm in semen after treatment (56 per cent). The level of hormone gradually increased in 15 patients, rapidly increased in four patients, but four patients had no obvious change of hormone level. Among the nine patients with varicocele, three persons (including one patient undergoing surgery) had normal sperm density after 3–4 months of treatment, continuing the treatment for another 2–3 months, wife of the patients gained pregnancies. After treatment, seven patients had gradually decreasing serum level of FSH, LH and T while two patients had increased serum level of hormones. Excluding the three pregnancy patients, it was showed that the sperm density increased (t=-3.342, p=0.004) after treatment, so did the forward moving sperm ratio (t=-4.037, p=0.001), but semen volume had no significant changes (t=-1.698, p=0.109). ConclusionThe treatment of varococele is important for the NOA with varicocele while andriol and tamoxifen is other method for the treatment of idiopathic NOA
Optical source profiles of brown carbon in size-resolved particulate matter from typical domestic biofuel burning over Guanzhong Plain, China
In this study, both PM2.5 and size-resolved source samples were collected from a "heated kang" and an advanced stove to investigate the optical properties of brown carbon (BrC). The light-absorption coefficient (babs), the absorption Angstrom exponent (AAE), and the mass absorption cross-section (MAC) of both water and methanol-extracted BrC were investigated. The methanol-extracted BrC (BrCmethanol) had higher light absorption than water-extracted BrC (BrCwater). The value of PM2.5 babs of BrCmethanol at 365 nm(b(abs365),methanol) dramatically decreased from 64,669.8Mm(-1) for straw burning in the "heated kang" to 1169.2 Mm(-1) formaize straw briquettes burning in the advanced stove at the same burning rate. The value of PM2.5 MAC for BrCmethanol at 365 nm (MAC(365), methanol) decreased from 1.8 m(2) g(-1) in the "heated kang" to 1.3 m(2) g-1 in the advanced stove. For smoldering burning in the "heated kang", babs365, methanol, MAC365, methanol, and K+ showed a unimodal distribution that peaked at sizes < 0.4 mu m. However, the babs365, methanol and MAC(365), methanol size distributions of the briquette burning in the advanced stove showed a bimodal pattern, with a large peak at sizes < 0.4 mu m and a minor peak in the size range of 4.7-5.8 mu m. The babs365, methanol value for sizes < 0.4 mu m (277.4 Mm(-1)) was only 12.3% compared to those obtained from the "heated kang". The burning rate did not influence the size distribution pattern of either the "heated kang" or the advanced stove. Results from a radiative model show that biomass burning is an important factor for light absorptivity, and the use of an advanced stove can reduce the simple forcing efficiency value by nearly 20% in UV bands compared to the "heated kang". Our results indicate that changing the combustion style from maize straw smoldering to briquette burning in an advanced stove can effectively reduce BrC emissions during heating seasons in rural areas of Guanzhong Plain. (C) 2017 Elsevier B.V. All rights reserved
Circulating miRNA Expression Profiling and Target Prediction in Patients Receiving Dexmedetomidine
Background/Aims: Circulating miRNAs could serve as biomarkers for diagnosis or prognosis of heart diseases and cerebrovascular diseases. Dexmedetomidine has protective effects in various organs. The effects of dexmedetomidine on circulating miRNAs remain unknown. Here, we investigated differentially expressed miRNA and to predict the target genes of the miRNA in patients receiving dexmedetomidine. Methods: The expression levels of circulating miRNAs of 3 patients were determined through high through-put miRNA sequencing technology. Target genes of the identified differentially expressed miRNAs were predicted using TargetScan 7.1 and miRDB v.5. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to conduct functional annotation and pathway enrichment analysis of target genes respectively. Results: Twelve differentially expressed miRNAs were identified. Five miRNAs were upregulated (hsa-miR-4508, hsa-miR-novel-chr8_87373, hsa-miR-30a-3p, hsa-miR-novel-chr16_26099, hsa-miR-4306) and seven miRNAs (hsa-miR-744-5p, hsa-miR-320a, hsa-miR-novel-chr9_90035, hsa-miR-101-3p, hsa-miR-150-5p, hsa-miR-342-3p, and hsa-miR-140-3p) were downregulated after administration of dexmedetomidine in the subjects. The target genes and pathways related to the differentially expressed miRNAs were predicted and analyzed. Conclusion: The differentially expressed miRNAs may be involved in the mechanisms of action of dexmedetomidine. Specific miRNAs, such as hsa-miR-101-3p, hsa-miR-150-5p and hsa-miR-140-3p, are new potential targets for further functional studies of dexmedetomidine
Impact of primary and secondary air supply intensity in stove on emissions of size-segregated particulate matter and carbonaceous aerosols from apple tree wood burning
In order to assess emission factors (EF) more accurately from household biomass burning, a series of laboratory controlled apple tree wood burning tests were conducted to measure the EFs of size-segregated particulate matter (PM) and carbonaceous aerosols. The controlled burning experiments were conducted with designed primary air (PA) and secondary air (SA) supply intensity. An optimum value of 7 m(3).h(-1) was found for SA, resulting the highest modified combustion efficiency (92.4 +/- 2.5%) as well as the lowest EFs of PM2.5 (0.13 +/- 0.01 g.MJ(-1)), OC (0.04 +/- 0.03 g.MJ(-1)) and EC (0.03 +/- 0.01 g.MJ(-1)). SA values of 7 and 10 m(3).h(-1) resulted the lowest EFs for all the different PM sizes. In a test with PA of 6 m(3.)h(-1) and SA of 7 m(3).h(-1), very low EFs were observed for 0C1 (8.2%), 0C2 (11.2%) and especially OP (Pyrolyzed OC) (0%, not detected), indicating nearly complete combustion under this air supply condition. Besides SA, higher PA was proved to have positive effects on PM and carbonaceous fraction emission reduction. For example, with a fixed SA of 1.5 m(3).h(-1), EFs of PM2.5 decreased from 0.64 to 0.27 g.MJ(-1) when PA increased from 6 to 15 m(3).h(-1) (P < 0.05). Similar reductions were also observed in EFs of OC, EC and size segregated PM
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