Influence of human body on massive MIMO indoor channels

© 2019 IEEE. Massive MIMO can dramatically improve capacity and spectral efficiency. However, it is not very clear whether it can significantly improve the signal blockage problem that exists in single antenna systems. In this paper, we investigate the impact of the human body on indoor massive MIMO channels, using practically measured channel data for a 32x8 massive MIMO system in a complex office environment. We introduce a parameter of Power Imbalance (PI) indices to estimate the wide-sense none-stationarity in multiple domains and another parameter of Channel Popularity Indices (CPI) to predict the popularity of MIMO channel. We find that in most cases, the presence of the human body still has a non- negligible negative impact. It decreases the ergodic capacity by about 8% and increases the path loss exponent by 1. In average, the ergodic capacity for NLOS channels are 15% higher than that for LOS

Measurement and Modeling of Wireless Off-Body Propagation Characteristics under Hospital Environment at 6-8.5 GHz

© 2013 IEEE. A measurement-based novel statistical path-loss model with a height-dependent factor and a body obstruction (BO) attenuation factor for off-body channel under a hospital environment at 6-8.5 GHz is proposed. The height-dependent factor is introduced to emulate different access point (AP) arrangement scenarios, and the BO factor is employed to describe the effect caused by different body-worn positions. The height-dependent path-loss exponent is validated to fluctuate from 2 to 4 with AP height increasing by employing both computer simulation and classical two-ray model theory. As further validated, the proposed model can provide more flexibility and higher accuracy compared with its existing counterparts. The presented channel model is expected to provide wireless link budget estimation and to further develop the physical layer algorithms for body-centric communication systems under hospital environments

Mortalin-p53 interaction in cancer cells is stress dependent and constitutes a novel target for liver cancer therapy

Poster AbstractsThis journal suppl. entitled: The International Liver Congress™ 2011 Abstract Book 46 annual meeting of the European Association for the Study of the LiverBACKGROUND AND AIMS: The mortality rate of HCC is high due to tumor recurrence and lack of effective treatment. By proteomics analysis of matched tumor and non-tumor tissues, mortalin was identified as a marker for hepatocellular carcinoma (HCC) metastasis and recurrence, suggesting its tight link in HCC development and recurrence. The aim of this study is to examine the role of mortalin in hepatocarcinogenesis. METHODS: The mortalin expression ...postprin

Isolation and characteristic of an aerobic denitrifier with high nitrogen removal efficiency

Paracoccus denitrificans DL-23, isolated from aerobic domesticated activated sludge, was demonstrated to have high ability of denitrification and heterotrophic nitrification under aerobic condition. After optimization (succinate, COD/N 10, 37°C, 160 rpm), DL-23 removed 420 and 860 mg/l NO3--N within 36 to 60 h of growth, respectively. DL-23 also removed 380 mg/l NH4+-N within 24 h with ammonia as nitrogen source. The maximum removal rate was 30.3 mg/l·h. Meanwhile, DL-23 exhibited aerobic nitrite reduction ability with 658 mg/l NO2--N within 48 h.Key words: Aerobic denitrification, heterotrophic nitrification, nitrogen removal, Paracoccus denitrificans

Clinical efficacy and safety of buyang huanwu decoction for acute ischemic stroke: a systematic review and meta-analysis of 19 randomized controlled trials

Buyang Huanwu Decoction (BHD) is a well-known traditional Chinese herbal prescription for treating stroke-induced disability. The objective of this study was to evaluate the efficacy and safety of BHD for acute ischemic stroke. A systematic literature search was performed in 6 databases until February 2012. Randomized controlled clinical trials (RCTs) that evaluate efficacy and safety of BHD for acute ischemic stroke were included. Nineteen RCTs with 1580 individuals were identified. The studies were generally of low methodological quality. Only one of the trial included death or dependency as a primary outcome measure. Only 4 trials reported adverse events. Meta-analysis showed the clinical effective rate of neurological deficit improvement favoring BHD when compared with western conventional medicines (WCM), P < 0.001. There is significant difference in the neurologic deficit score between the BHD treatment group and the WCM control group, P < 0.001. In Conclusion, BHD appears to improve neurological deficit and seems generally safe in patients with acute ischemic stroke. However, the current evidence is insufficient to support a routine use of BHD for acute ischemic stroke due to the poor methodological quality and lack of adequate safety data of the included studies. Further rigorously designed trials are required.published_or_final_versio

Macrophage TNF-α mediates parathion-induced airway hyperreactivity in guinea pigs.

Organophosphorus pesticides (OPs) are implicated in human asthma. We previously demonstrated that, at concentrations that do not inhibit acetylcholinesterase activity, the OP parathion causes airway hyperreactivity in guinea pigs as a result of functional loss of inhibitory M2 muscarinic receptors on parasympathetic nerves. Because macrophages are associated with asthma, we investigated whether macrophages mediate parathion-induced M2 receptor dysfunction and airway hyperreactivity. Airway physiology was measured in guinea pigs 24 h after a subcutaneous injection of parathion. Pretreatment with liposome-encapsulated clodronate induced alveolar macrophage apoptosis and prevented parathion-induced airway hyperreactivity in response to electrical stimulation of the vagus nerves. As determined by qPCR, TNF-α and IL-1β mRNA levels were increased in alveolar macrophages isolated from parathion-treated guinea pigs. Parathion treatment of alveolar macrophages ex vivo did not significantly increase IL-1β and TNF-α mRNA but did significantly increase TNF-α protein release. Consistent with these data, pretreatment with the TNF-α inhibitor etanercept but not the IL-1β receptor inhibitor anakinra prevented parathion-induced airway hyperreactivity and protected M2 receptor function. These data suggest a novel mechanism of OP-induced airway hyperreactivity in which low-level parathion activates macrophages to release TNF-α-causing M2 receptor dysfunction and airway hyperreactivity. These observations have important implications regarding therapeutic approaches for treating respiratory disease associated with OP exposures

Symptoms of posttraumatic stress disorder and depression among bereaved and non-bereaved survivors following the 2008 Sichuan earthquake

Many studies have suggested that unexpected death of a loved one is an important risk factor of posttraumatic stress disorder (PTSD) and depression among disaster survivors, but few have examined the magnitude of psychiatric morbidities among bereaved survivors. This study examined the prevalence rates of clinically significant PTSD and depressive symptoms and their associated risk factors among Chinese adult survivors following the 2008 Sichuan earthquake. Two hundred and fifty-one bereaved adults were compared with 1474 non-bereaved adult survivors. The estimated rates of PTSD and depressive symptoms were 65.6% and 64.8% for those who lost first-degree family members, 34.1% and 45.5% for those who lost second-degree relatives, and 27.1% and 37.5% for non-bereaved survivors respectively. Loss of a child was a significant predictor of psychopathological symptoms. The results suggested that effective and sustainable mental health services were required, especially for bereaved single-child parents. © 2012 Elsevier Ltd.postprin

Kaon decays and the flavour problem

After a brief introduction to the so-called flavour problem, we discuss the role of rare K decays in probing the mechanism of quark-flavour mixing. Particular attention is devoted to the formulation of the Minimal Flavour Violation hypothesis, as a general and natural solution to the flavour problem, and to the fundamental role of K -> pi nu nu-bar decays in testing this scenario.Comment: 10 pages, 6 figures, contribution to TH 2002 (Paris, July 2002