Multi-Floor Indoor Localization Based on Multi-Modal Sensors.

High-precision indoor localization is growing extremely quickly, especially for multi-floor scenarios. The data on existing indoor positioning schemes, mainly, come from wireless, visual, or lidar means, which are limited to a single sensor. With the massive deployment of WiFi access points and low-cost cameras, it is possible to combine the above three methods to achieve more accurate, complete, and reliable location results. However, the existing SLAM rapidly advances, so hybrid visual and wireless approaches take advantage of this, in a straightforward manner, without exploring their interactions. In this paper, a high-precision multi-floor indoor positioning method, based on vision, wireless signal characteristics, and lidar is proposed. In the joint scheme, we, first, use the positioning data output in lidar SLAM as the theoretical reference position for visual images; then, use a WiFi signal to estimate the rough area, with likelihood probability; and, finally, use the visual image to fine-tune the floor-estimation and location results. Based on the numerical results, we show that the proposed joint localization scheme can achieve 0.62 m of 3D localization accuracy, on average, and a 1.24-m MSE for two-dimensional tracking trajectories, with an estimation accuracy for the floor equal to 89.22%. Meanwhile, the localization process takes less than 0.25 s, which is of great importance for practical implementation.

Multi-UAV Content Caching Strategy and Cooperative, Complementary Content Transmission Based on Coalition Formation Game.

The transmission of a large amount of video and picture content brings more challenges to wireless communication networks. Unmanned aerial vehicle (UAV)-aided small cells with active content caching deployed on cellular networks are recognized as a promising way to alleviate wireless backhaul and support flexible coverage. However, a UAV cannot operate for a long time due to limited battery life, and its caching capacity is also limited. For this, a multi-UAV content-caching strategy and cooperative, complementary content transmission among UAVs are jointly studied in this paper. Firstly, a user-clustering-based caching strategy is designed, where user clustering is based on user similarity, concurrently taking into consideration similarities in content preference and location. Then, cooperative, complementary content transmission between multiple UAVs is modeled as a coalition formation game (CFG) to maximize the utility of the whole network. Finally, the effectiveness of the proposed algorithms is demonstrated through numerical simulations.

A Cooperative Shared Control Scheme Based on Intention Recognition for Flexible Assembly Manufacturing.

Human-robot collaboration (HRC) has been widely utilized in industrial manufacturing and requires a human to cooperate with a robot at the same workspace. However, as HRC focuses on workspace sharing along with independent work, it is not a real collaboration between a human and a robot and, thus, cannot guarantee a smooth cooperation and synchronous operation. To this end, a cooperative shared control scheme based on intention recognition is proposed in this study by sharing workspace and time. In the proposed method, a classification algorithm based on three-dimensional (3D) point cloud is utilized to recognize the human operation intention. Then, the robot can select a suitable tool to match the human's operation. A robot motion control algorithm is developed to detect the obstacles in the HRC process. A cooperative control strategy is introduced to achieve synchronous operation. A simple assembly task is also performed to demonstrate the proposed scheme's effectiveness. The proposed HRC method with shared control can be extended to more complicated and delicate flexible tasks in assembly manufacturing.

GammaTile® brachytherapy in the treatment of recurrent glioblastomas.

BACKGROUND: GammaTile® (GT) is a recent U.S. Food and Drug Administration (FDA) cleared brachytherapy platform. Here, we report clinical outcomes for recurrent glioblastoma patients after GT treatment following maximal safe resection. METHODS: We prospectively followed twenty-two consecutive Isocitrate Dehydrogenase (IDH) wild-type glioblastoma patients (6 O6-Methylguanine-DNA methyltransferase methylated (MGMTm); sixteen MGMT unmethylated (MGMTu)) who underwent maximal safe resection of recurrent tumor followed by GT placement. RESULTS: The cohort consisted of 14 second and eight third recurrences. In terms of procedural safety, there was one 30-day re-admission (4.5%) for an incisional cerebrospinal fluid leak, which resolved with lumbar drainage. No other wound complications were observed. Six patients (27.2%) declined in Karnofsky Performance Score (KPS) after surgery due to worsening existing deficits. One patient suffered a new-onset seizure postsurgery (4.5%). There was one (4.5%) 30-day mortality from intracranial hemorrhage secondary to heparinization for an ischemic limb. The mean follow-up was 733 days (range 279-1775) from the time of initial diagnosis. Six-month local control (LC6) and twelve-month local control (LC12) were 86 and 81%, respectively. Median progression-free survival (PFS) was comparable for MGMTu and MGMTm patients (~8.0 months). Median overall survival (OS) was 20.0 months for the MGMTu patients and 37.4 months for MGMTm patients. These outcomes compared favorably to data in the published literature and an independent glioblastoma cohort of comparable patients without GT treatment. CONCLUSIONS: This clinical experience supports GT brachytherapy as a treatment option in a multi-modality treatment strategy for recurrent glioblastomas.

High Accurate Environmental Sound Classification: Sub-Spectrogram Segmentation versus Temporal-Frequency Attention Mechanism.

In the important and challenging field of environmental sound classification (ESC), a crucial and even decisive factor is the feature representation ability, which can directly affect the accuracy of classification. Therefore, the classification performance often depends to a large extent on whether the effective representative features can be extracted from the environmental sound. In this paper, we firstly propose a sub-spectrogram segmentation with score level fusion based ESC classification framework, and we adopt the proposed convolutional recurrent neural network (CRNN) for improving the classification accuracy. By evaluating numerous truncation schemes, we numerically figure out the optimal number of sub-spectrograms and the corresponding band ranges, and, on this basis, we propose a joint attention mechanism with temporal and frequency attention mechanisms and use the global attention mechanism when generating the attention map. Finally, the numerical results show that the two frameworks we proposed can achieve 82.1% and 86.4% classification accuracy on the public environmental sound dataset ESC-50, respectively, which is equivalent to more than 13.5% improvement over the traditional baseline scheme.

The use of whole-body fluorine-18-fluorodeoxyglucose positron emission tomography integrated with computed tomography for accurate staging and surveillance in the case of mucosa-associated lymphoid tissue.

We present the case of a 79-year-old male, who was initially treated for mucosa-associated lymphoid tissue lymphoma (MALT lymphoma) of the right eyelid, and later for disease relapse in the stomach. During follow up, he was noted to have developed left arm nodules just medial to the proximal biceps muscle, which were found to be multiply enlarged lymph nodes on subsequent ultrasound imaging. Excisional biopsy of these nodes revealed MALT lymphoma. He was initially referred for consideration of radiation, but a restaging F-18 fluorodeoxyglucose positron emission tomography integrated with computed tomography (F-18 FDG PET/CT) further identified a focus of suspicious uptake in left calf, which was later also biopsy proven to be MALT lymphoma. His disease was upstaged as the result of this later finding, and the overall recommendation for treatment changed to favor systemic treatment with Rituximab.

Uptake of Pb(II) onto microplastic-associated biofilms in freshwater: Adsorption and combined toxicity in comparison to natural solid substrates.

In the present study, microplastic-associated biofilms were cultivated in an urban lake and a reservoir using virgin expanded polystyrene (PS). The uptake of Pb(II) onto both natural (suspended particles and surficial sediment) and anthropogenic (virgin microplastics and microplastic-associated biofilms) solid substrates was investigated and compared as a function of contact time, pH, and ionic strength in batch adsorption experiments. The adsorption isotherms revealed that biofilms enhanced the adsorption capacity of Pb(II) onto microplastics; however, natural substrates still exhibited a higher capacity. Ionic strength and pH significantly influenced the adsorption of Pb(II) onto all of the solid substrates. Under neutral conditions, competitive adsorption of Pb(II) was observed between anthropogenic solid substrates and natural substrates, which may further alter the distribution of Pb(II) among these solid substrates. The combined toxicity tests of Pb(II) and each solid substrate were carried out using Daphnia magna, the results indicated biofilm enhanced the combined toxicity of Pb(II) and microplastics. Therefore, biofilms not only intensified the vector role of microplastics in the migration of heavy metals in freshwater, but also enhanced their combined toxicity, which may have further potential ecological risks to freshwater ecosystems.

The Structures of Gd(III) Chelates Conjugated at the Periphery of 3-(1'-Hexyloxy)ethyl-3-devinylpyropheophorbide-a (HPPH) Have a Significant Impact on the Imaging and Therapy of Cancer.

3-(1'-Hexyloxyethyl)-3-devinyl-pyropheophorbide-a (HPPH or Photochlor), a tumor-avid chlorophyll-a derivative currently undergoing human clinical trials, was conjugated at various peripheral positions (position-17 or 20) of HPPH with either Gd(III)-aminobenzyl-DTPA (Gd(III) DTPA) or Gd(III)-aminoethylamido-DOTA (Gd(III) DOTA). The corresponding conjugates were evaluated for in vitro PDT efficacy, T1 , T2 relaxivities, in vivo fluorescence, and MR imaging under similar treatment parameters. Among these analogs, the water-soluble Gd(III)-aminoethylamido-DOTA linked at position-17 of HPPH, i. e., HPPH-17-Gd(III) DOTA, demonstrated strong potential for tumor imaging by both MR and fluorescence, while maintaining the PDT efficacy in BALB/c mice bearing Colon-26 tumors (7/10 mice were tumor free on day 60). In contrast to Gd(III) DTPA (Magnevist) and Gd(III) DOTA (Dotarem), the HPPH-Gd(III) DOTA retains in the tumor for a long period of time (24 to 48 h) and provides an option of fluorescence-guided cancer therapy. Thus, a single agent can be used for cancer-imaging and therapy. However, further detailed pharmacokinetic, pharmacodynamic, and toxicological studies of the conjugate are required before initiating Phase I human clinical trials.

Wi-Alarm: Low-Cost Passive Intrusion Detection Using WiFi.

In this paper, we present a WiFi-based intrusion detection system called Wi-Alarm. Motivated by our observations and analysis that raw channel state information (CSI) of WiFi is sensitive enough to monitor human motion, Wi-Alarm omits data preprocessing. The mean and variance of the amplitudes of raw CSI data are used for feature extraction. Then, a support vector machine (SVM) algorithm is applied to determine detection results. We prototype Wi-Alarm on commercial WiFi devices and evaluate it in a typical indoor scenario. Results show that Wi-Alarm reduces much computational expense without losing accuracy and robustness. Moreover, different influence factors are also discussed in this paper.

Joint Optimization of Interference Coordination Parameters and Base-Station Density for Energy-Efficient Heterogeneous Networks.

Heterogeneous networks (HetNets), consisting of macro-cells and overlaying pico-cells, have been recognized as a promising paradigm to support the exponential growth of data traffic demands and high network energy efficiency (EE). However, for two-tier heterogeneous architecture deployment of HetNets, the inter-tier interference will be challenging. Time domain further-enhanced inter-cell interference coordination (FeICIC) proposed in 3GPP Release-11 becomes necessary to mitigate the inter-tier interference by applying low power almost blank subframe (ABS) scheme. Therefore, for HetNets deployment in reality, the pico-cell range expansion (CRE) bias, the power of ABS and the density of pico base stations (PBSs) are three important factors for the network EE improvement. Aiming to improve the network EE, the above three factors are jointly considered in this paper. In particular, we first derive the closed-form expression of the network EE as a function of pico CRE bias, power reduction factor of low power ABS and PBS density based on stochastic geometry model. Then, the approximate relationship between pico CRE bias and power reduction factor is deduced, followed by a linear search algorithm to get the near-optimal pico CRE bias and power reduction factor together at a given PBS density. Next, a linear search algorithm is further proposed to optimize PBS density based on fixed pico CRE bias and power reduction factor. Due to the fact that the above pico CRE bias and power reduction factor optimization and PBS density optimization are optimized separately, a heuristic algorithm is further proposed to optimize pico CRE bias, power reduction factor and PBS density jointly to achieve global network EE maximization. Numerical simulation results show that our proposed heuristic algorithm can significantly enhance the network EE while incurring low computational complexity.

All Tree Amplitudes of 6D (2,0) Supergravity: Interacting Tensor Multiplets and the K3 Moduli Space.

We present a twistorlike formula for the complete tree-level S matrix of six-dimensional (6D) (2,0) supergravity coupled to 21 Abelian tensor multiplets. This is the low-energy effective theory that corresponds to type IIB superstring theory compactified on a K3 surface. The formula is expressed as an integral over the moduli space of certain rational maps of the punctured Riemann sphere. By studying soft limits of the formula, we are able to explore the local moduli space of this theory, {[SO(5,21)]/[SO(5)×SO(21)]}. Finally, by dimensional reduction, we also obtain a new formula for the tree-level S matrix of 4D N=4 Einstein-Maxwell theory.

DNA Nanocarriers: Programmed to Deliver.

Simple base-pairing rules of complementarity, perfected by evolution for encoding genetic information, provide unprecedented control over the process of DNA self-assembly. These rules allow us to build exquisite nanostructures and rationally design their morphology, fine-tune their chemical properties, and program their response to environmental stimuli. DNA nanostructures have emerged as promising candidates for transporting drugs across various physiological barriers of the body. In this review, we discuss the strategies used to transform DNA nanostructures into drug delivery vehicles. We provide an overview of recent attempts at using them to deliver small molecule drugs and macromolecular cargoes and present the challenges that lay ahead for these synthetic vectors as they set new paradigms in the field of nanotechnology and medicine.

Clinical Predictors of Port Infections in Adult Patients with Hematologic Malignancies.

PURPOSE: To identify clinical predictors of port infections in adult patients with hematologic malignancies. MATERIALS AND METHODS: A retrospective chart review identified 223 adult patients (age ≥ 18 y) with hematologic malignancies, including lymphoma (n = 163), leukemia (n = 49), and others (n = 11), who had a port placed from 2012 to 2015. Early (< 30 d after port placement) and overall port infections (bloodstream and site infections) were recorded. To elucidate clinical predictors for early and overall port infections, proportional subdistribution hazard regression (PSHREG) analyses were conducted with variables including patients' demographics, medications used, laboratory data, and port characteristics. RESULTS: Total duration of follow-up was 83,722 catheter-days (median per patient, 274 catheter-days). Early and overall port infections were identified in 8 (3.6%) and 26 (11.7%) patients, respectively. Early and overall infection rates were 1.2 and 0.3 infections/1,000 catheter-days, respectively. Backward stepwise multivariate PSHREG analyses identified hypoalbuminemia (< 3.5 mg/dL) at the time of port placement (hazard ratio = 5.03; 95% confidence interval, 1.14-22.16; P = .03) and steroid use (> 30 d cumulatively during follow-up period) (hazard ratio = 3.41; 95% confidence interval, 1.55-7.47; P = .002) as independent risk factors for early and overall port infections, respectively. CONCLUSIONS: In adult patients with hematologic malignancies, hypoalbuminemia at the time of port placement was a clinical predictor for early port infections, whereas steroid use was a clinical predictor for overall port infections.

Energy Efficient Pico Cell Range Expansion and Density Joint Optimization for Heterogeneous Networks with eICIC.

Heterogeneous networks, constituted by conventional macro cells and overlaying pico cells, have been deemed a promising paradigm to support the deluge of data traffic with higher spectral efficiency and Energy Efficiency (EE). In order to deploy pico cells in reality, the density of Pico Base Stations (PBSs) and the pico Cell Range Expansion (CRE) are two important factors for the network spectral efficiency as well as EE improvement. However, associated with the range and density evolution, the inter-tier interference within the heterogeneous architecture will be challenging, and the time domain Enhanced Inter-cell Interference Coordination (eICIC) technique becomes necessary. Aiming to improve the network EE, the above factors are jointly considered in this paper. More specifically, we first derive the closed-form expression of the network EE as a function of the density of PBSs and pico CRE bias based on stochastic geometry theory, followed by a linear search algorithm to optimize the pico CRE bias and PBS density, respectively. Moreover, in order to realize the pico CRE bias and PBS density joint optimization, a heuristic algorithm is proposed to achieve the network EE maximization. Numerical simulations show that our proposed pico CRE bias and PBS density joint optimization algorithm can improve the network EE significantly with low computational complexity.

[Reconsideration for ischemic stroke risk factors in youth].

OBJECTIVE: To explore the related ischemic stroke (IS) risk factors in youth and the importance of sleep quality in young ischemic stroke. METHODS: A total of 219 patients aged 18 to 45 years (166 males, 53 females) with an initial onset of ischemic stroke from First Affiliated Hospital, Zhengzhou University and Puyang People's Hospital during June 2011 to February 2013, were recruited as the study cases. Meanwhile 231 patients aged 46 to 80 years (170 males, 61 females) from the same hospitals were selected as the elderly control group. And 149 young persons aged 18 to 45 years undergoing normal physical examinations from the same hospitals were taken as youth control group. For all cases, their ischemic stroke related risk factors and especially the importance of sleep quality were analyzed. Prospective analyses were conducted to re-considerate the related ischemic stroke risk factors in youth. RESULTS: Hypertension history, high cholesterol, diabetes, smoking and drinking, bad sleep quality, family history of stroke and hyperhomocysteinemia were associated with the onset of young ischemic stroke. The decreasing exposure rates were history of hypertension, smoking, poor sleep quality, hyperlipidemia, alcoholism, hyperhomocysteinemia and a family history of stroke and diabetes. In ischemic stroke young patients, bad sleep quality accounted for 55.7% and ranked third among all risk factors. CONCLUSION: The risk factors of young ischemic stroke ranks are different with other studies. As one of the most important factors for youth ischemic stroke, poor sleep quality should not be neglected.

Correlation analysis of sleep quality and youth ischemic stroke.

OBJECTIVE: To study risk factors related to ischemic stroke (IS) in youth and the influence of sleep quality on youth ischemic stroke incidence. METHODS: 223 patients aged 18 to 45 years who were admitted to Puyang People's Hospital from June 2011 to February 2013 with a first-ever ischemic stroke were selected as the research cases. 158 young people with a normal physical examination were selected as the control group. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was used to analyse the correlation between sleep quality and youth IS incidence. The U.S. National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (MRS) scores were used to assess cases' state of illness and prognosis three months after IS. RESULTS: Univariate and multivariate logistic regression analysis showed that the association of these risk factors with youth IS incidence, from highest to lowest, was hypertension, hyperlipidaemia, smoking history, high homocysteine, the quality of sleep, family history of stroke, and alcoholism. Poor sleep quality ranked fifth among all risk factors and was positively correlated with poor prognosis for youth IS patients. CONCLUSION: The results of this study showed that sleep quality is an important factor in the pathogenesis and prognosis of youth IS.