Constructing an Indoor Floor Plan Using Crowdsourcing Based on Magnetic Fingerprinting

A large number of indoor positioning systems have recently been developed to cater for various location-based services. Indoor maps are a prerequisite of such indoor positioning systems; however, indoor maps are currently non-existent for most indoor environments. Construction of an indoor map by external experts excludes quick deployment and prevents widespread utilization of indoor localization systems. Here, we propose an algorithm for the automatic construction of an indoor floor plan, together with a magnetic fingerprint map of unmapped buildings using crowdsourced smartphone data. For floor plan construction, our system combines the use of dead reckoning technology, an observation model with geomagnetic signals, and trajectory fusion based on an affinity propagation algorithm. To obtain the indoor paths, the magnetic trajectory data obtained through crowdsourcing were first clustered using dynamic time warping similarity criteria. The trajectories were inferred from odometry tracing, and those belonging to the same cluster in the magnetic trajectory domain were then fused. Fusing these data effectively eliminates the inherent tracking errors originating from noisy sensors; as a result, we obtained highly accurate indoor paths. One advantage of our system is that no additional hardware such as a laser rangefinder or wheel encoder is required. Experimental results demonstrate that our proposed algorithm successfully constructs indoor floor plans with 0.48 m accuracy, which could benefit location-based services which lack indoor maps

Geriatric benign paroxysmal positional vertigo: a single-center study

Objective: To compare the clinical features, risk factors, distribution of Benign Paroxysmal Positional Vertigo (BPPV) subtypes, and effectiveness of canalith repositioning between geriatric and non-geriatric patients with BPPV. Methods: A total of 400 patients with BPPV were enrolled. Canalith repositioning was performed according to the semicircular canals involved. Patients were divided by age into a geriatric group (≥60 years) and a non-geriatric group (20–59 years). Clinical characteristics, potential age-related risk factors, distribution of subtypes, and effectiveness of canalith repositioning were compared between the groups. Results: Female sex was significantly more common in all age groups, with a peak female-to-male ratio of 5.1:1 in the group aged 50–59 years. There was a higher proportion of men in the geriatric group. A history of disease associated with atherosclerosis was significantly more common in the geriatric group (p < 0.05). Migraine was significantly more common in the non-geriatric group (p = 0.018), as was posterior canal BPPV. The horizontal canal BPPV (especially horizontal canal BPPV-cupulolithiasis), and multicanal BPPV subtypes were more common in the geriatric group, whereas anterior canal BPPV was more common in the non-geriatric group. Two canalith repositioning sessions were effective in 58.0% of the geriatric cases and in 72.6% of the non-geriatric cases (p = 0.002). There was a tendency for the effectiveness of canalith repositioning to decrease with increasing age. Conclusion: BPPV was more common in women. However, the proportion of men with BPPV increased with age. Elderly patients often had a history of diseases associated with atherosclerosis (i.e., hypertension, diabetes, and hyperlipidemia). The horizontal canal BPPV (particularly horizontal canal BPPV-cupulolithiasis) and multicanal BPPV subtypes were more common and the anterior canal BPPV subtype was less common in elderly patients. The effectiveness of canalith repositioning may decrease with age. Therefore, older patients should receive more comprehensive medical treatment. Level of evidence: 4

Indoor Air Pollution and Human Perception in Public Buildings in Tianjin, China

AbstractIn recent years public health problems caused by indoor air pollution, such as Sick Building Syndrome (SBS), have been drawing strong public concerns. This study aims at investigating the indoor environment quality (IEQ) and people's perception in public buildings in Tianjin, China. Indoor environment parameters including air temperature, relative humidity, air speed, TVOC, formaldehyde and CO2 were monitored at two office buildings and two shopping malls, which located in Tianjin region. The measurement was done during January 2014-December 2014. Occupants’ perception on indoor air quality (IAQ), thermal environment, and SBS symptoms were surveyed by questionnaire. Approximately 31.5% and 2.5% of the samples in two offices exceeded the Chinese National Indoor Air Quality Standard for formaldehyde (0.08mg/m3), as well as 19.9% and 55.3% of samples in two shopping malls. High formaldehyde concentration, especially in the mall, should be of health effect concern. It was indicated that indoor air quality (IAQ) may lead to SBS symptoms in public building in Tianjin

Effects of Broad-Spectrum Antibiotic (Florfenicol) on Resistance Genes and Bacterial Community Structure of Water and Sediments in an Aquatic Microcosm Model

This study evaluates the effects of a broad-spectrum antibiotic (florfenicol) on antibiotic resistance genes (ARGs) and bacterial community structure in aquatic environments. We constructed an indoor aquatic microcosm model, adding different concentrations of florfenicol (0.1, 1, 10, 100 mg L−1), and water and sediment samples were collected after 0, 7, 30, and 60 days. qPCR and 16S rDNA amplicon sequencing were used to study the changes in the ARGs and bacterial community structure of the collected samples. The results show that the inclusion of florfenicol resulted in an increased abundance of the floR and optrA genes. Adding 100 mg L−1 florfenicol to the water increased the abundance of optrA gene copies with the maximum on the Day 7, and increased the abundance of floR gene copies with the maximum on Day 30. Adding 100 mg L−1 florfenicol to the sediment increased the abundance of floR and optrA genes by one order of magnitude on Day 60. Meanwhile, the average number of operational taxonomic units (OTUs) in the water samples was 257, and the average number of OTUs in sediment samples was 823. The bacterial community diversity and richness in sediments were higher than those in water. The difference between the maximal and minimal values of the Shannon diversity index in the water and sediment samples was 4.36 and 1.95, respectively. The effect of florfenicol on the bacterial community structure in water was much higher than that in sediment. At 30 days, the diversity index and richness index of the florfenicol treatment groups with 1 and 10 mg L−1 concentrations began to increase; at 60 days, the diversity and richness indices of the 100 mg L−1 florfenicol treatment group began to increase. The samples at the same sampling time in the sediments clustered closer together. The results of this study provide a scientific basis for guiding the rational use of florfenicol in aquaculture, maintaining a healthy and stable microecological environment in aquaculture, and provide theoretical data for environmental ecological risk assessment and safety management caused by microbial resistance under the abuse of florfenicol

Clinical study on effect of wrist-ankle acupuncture on incidence of hypertension after intubation during induction of general anesthesia

Objective To observe the effect of wrist-ankle acupuncture on the incidence of hypertension after tracheal intubation during induction of general anesthesia. Methods 200 patients receiving selective surgery under tracheal intubation and general anesthesia in our Hospital were selected and divided into control group and wrist-ankle acupuncture group using the random number table method, with 100 patients in each group. Sufentanil, cisatracurium besilate, remifentanil, etomidate and lidocaine hydrochloride were used for anesthesia induction, and intravenously injected according to the onset time of drugs, successively. The wrist-ankle acupuncture group was needled in bilateral upper 1, 2 and 3 areas, while the control group was treated with false acupuncture.Blood pressure and related blood biochemical indexes were measured and observed at different stages in each group. Result The incidence of blood pressure exceeding 20% and 30% of basal blood pressure within 5 minutes after intubation was as follows:wrist-ankle acupuncture group 11.83% and 6.45%; control group 29.79% and 22.34%, The incidence in the study group was lower than that in the control group. Norepinephrine concentration in the wrist-ankle acupuncture group was significantly lower than that before induction (P < .05), and plasma Norepinephrine concentration in the wrist-ankle acupuncture group was significantly lower than that in the control group after intubation (P < .05). The plasma Norepinephrine concentration in the wrist-ankle acupuncture group was significantly lower than that in the control group after intubation (P < .05) Conclusion wrist-ankle acupuncture can prevent hypertension after intubation during anesthesia induction. Moreover, it is safe, effective, minimally invasive. Therefore, it is easy to be popularized in clinical practice

Hyperhomocysteinemia in ApoE-/- Mice Leads to Overexpression of Enhancer of Zeste Homolog 2 via miR-92a Regulation.

Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular diseases, such as atherosclerosis. HHcy promotes atherogenesis by modifying the histone methylation patterns and miRNA regulation. In this study, we investigated the effects of homocysteine (Hcy) on the expression of enhancer of zeste homolog 2 (EZH2), and tested our hypothesis that Hcy-induced atherosclerosis is mediated by increased EZH2 expression, which is regulated by miR-92a. The levels of EZH2 and H3K27me3 were increased in the aorta of ApoE-/- mice fed a high-methionine diet for 16 weeks, whereas miR-92a expression was decreased. Over-expression of EZH2 increased H3K27me3 level and the accumulation of total cholesterol and triglycerides in the foam cells. Furthermore, upregulation of miR-92a reduced EZH2 expression in the foam cells. These data suggested that EZH2 plays a key role in Hcy-mediated lipid metabolism disorders, and that miR-92a may be a novel therapeutic target in Hcy-related atherosclerosis