A New Three-Dimensional Indoor Positioning Mechanism Based on Wireless LAN

The researches on two-dimensional indoor positioning based on wireless LAN and the location fingerprint methods have become mature, but in the actual indoor positioning situation, users are also concerned about the height where they stand. Due to the expansion of the range of three-dimensional indoor positioning, more features must be needed to describe the location fingerprint. Directly using a machine learning algorithm will result in the reduced ability of classification. To solve this problem, in this paper, a “divide and conquer” strategy is adopted; that is, first through k-medoids algorithm the three-dimensional location space is clustered into a number of service areas, and then a multicategory SVM with less features is created for each service area for further positioning. Our experiment shows that the error distance resolution of the approach with k-medoids algorithm and multicategory SVM is higher than that of the approach only with SVM, and the former can effectively decrease the “crazy prediction.

Separating and characterizing functional alkane degraders from crude-oil-contaminated sites via magnetic nanoparticle-mediated isolation

Uncultivable microorganisms account for over 99% of all species on the planet, but their functions are yet not well characterized. Though many cultivable degraders for n-alkanes have been intensively investigated, the roles of functional n-alkane degraders remain hidden in the natural environment. This study introduces the novel magnetic nanoparticle-mediated isolation (MMI) technology in Nigerian soils and successfully separates functional microbes belonging to the families Oxalobacteraceae and Moraxellaceae, which were dominant and responsible for alkane metabolism in situ. The alkR-type n-alkane monooxygenase genes, instead of alkA- or alkP-type, were the key functional genes involved in the n-alkane degradation process. Further physiological investigation via a BIOLOG PM plate revealed some carbon (Tween 20, Tween 40 and Tween 80) and nitrogen (tyramine, L-glutamine and D-aspartic acid) sources promoting microbial respiration and n-alkane degradation. With further addition of promoter carbon or nitrogen sources, the separated functional alkane degraders significantly improved n-alkane biodegradation rates. This suggests that MMI is a promising technology for separating functional microbes from complex microbiota, with deeper insight into their ecological functions and influencing factors. The technique also broadens the application of the BIOLOG PM plate for physiological research on functional yet uncultivable microorganisms

RANK ONE PERTURBATIONS AND APPLICATIONS

The role of rank one perturbations in transforming the eigenstructure of a matrix has long been considered in the context of applications, especially in linear control systems. Three cases are examined as part of this work: First, we propose a practical method to place the system eigenvalues in any desired locations for a system that is completely controllable via an appropriate choice of feedback control, found via sequential rank one perturbations. Second, we stabilize a system that is stabilizable but not neccessarily completely controllable by placing the system eigenvalues in the open left-half complex plane through feedback via rank one perturbations. Third, a choice of feedback control is proposed in order to achieve that a trajectory of a linear control system eventually enters an orthant of Rn and remains therein for all time thereafter. The last situation is achieved by imposing the strong Perron-Frobenius property and involves altering an eigenvalue as well as its corresponding eigenvector appropriately.P-matrices have positive principal minors and include many well-known matrix classes (positive definite, totally positive, M-matrices etc.) How does one construct a generic P-matrix? Specifically, is there a characterization of P-matrices that lends itself to the tractable construction of every P-matrix? To answer these questions positively, a recursive method is employed that is based on a characterization of rank-one perturbations that preserve the class of P-matrices.Nonnegative matrices have long been a source of interesting and challenging mathematical problems. They are real matrices with all their entries being nonnegative and arise in a number of important application areas: communications systems, biological systems, economics, ecology, computer sciences, machine learning, and many other engineering systems. We explore applications of rank one perturbations on the nonnegative inverse eigenvalue problem as well as on stochastic matrices

Meta-analysis of PET/CT detect lymph nodes metastases of cervical cancer

The aim of this study was to assess the diagnostic value of PET/CT for metastatic lymph nodes in cervical cancer patients

Transcriptional Factors Mediating Retinoic Acid Signals in the Control of Energy Metabolism

Retinoic acid (RA), an active metabolite of vitamin A (VA), is important for many physiological processes including energy metabolism. This is mainly achieved through RA-regulated gene expression in metabolically active cells. RA regulates gene expression mainly through the activation of two subfamilies in the nuclear receptor superfamily, retinoic acid receptors (RARs) and retinoid X receptors (RXRs). RAR/RXR heterodimers or RXR/RXR homodimers bind to RA response element in the promoters of RA target genes and regulate their expressions upon ligand binding. The development of metabolic diseases such as obesity and type 2 diabetes is often associated with profound changes in the expressions of genes involved in glucose and lipid metabolism in metabolically active cells. RA regulates some of these gene expressions. Recently, in vivo and in vitro studies have demonstrated that status and metabolism of VA regulate macronutrient metabolism. Some studies have shown that, in addition to RARs and RXRs, hepatocyte nuclear factor 4α, chicken ovalbumin upstream promoter-transcription factor II, and peroxisome proliferator activated receptor β/δ may function as transcriptional factors mediating RA response. Herein, we summarize current progresses regarding the VA metabolism and the role of nuclear receptors in mediating RA signals, with an emphasis on their implication in energy metabolism

Degradation of Carbendazim by Molecular Hydrogen on Leaf Models

Although molecular hydrogen can alleviate herbicide paraquat and Fusarium mycotoxins toxicity in plants and animals, whether or how molecular hydrogen influences pesticide residues in plants is not clear. Here, pot experiments in greenhouse revealed that degradation of carbendazim (a benzimidazole pesticide) in leaves could be positively stimulated by molecular hydrogen, either exogenously applied or with genetic manipulation. Pharmacological and genetic increased hydrogen gas could increase glutathione metabolism and thereafter carbendazim degradation, both of which were abolished by the removal of endogenous glutathione with its synthetic inhibitor, in both tomato and in transgenic Arabidopsis when overexpressing the hydrogenase 1 gene from Chlamydomonas reinhardtii. Importantly, the antifungal effect of carbendazim in tomato plants was not obviously altered regardless of molecular hydrogen addition. The contribution of glutathione-related detoxification mechanism achieved by molecular hydrogen was confirmed. Our results might not only illustrate a previously undescribed function of molecular hydrogen in plants, but also provide an environmental-friendly approach for the effective elimination or reduction of pesticides residues in crops when grown in pesticides-overused environmental conditions

Significance of three reservoir profiles for the risk exploration in Ordos Basin

The Ordos Basin went through six main stages of geological evolution, developed three sets of soure rocks, two unconformities, several sets of reservoirs and caprocks, and had three typical petroleum systems, i.e. Lower Paleozoic Ordovician gas reservoirs, Upper Paleozoic Carboniferous-Permian gas reservoirs, and Mesozoic Triassic-Jurassic oil reservoirs. Three well-tie profiles of oil and gas reservoirs in the basin are analyzed, which are the Wuzhong-Mizhi profile, Guyuan-Yichuan profile, and Baotou-Chengcheng profile. The size and distribution of the oil and gas reservoirs are controlled by the spatial distribution of soure rocks. Mesozoic oil reservoirs are located inside or near hydrocarbon depressions, where oil and gas had a short secondary migration distance. Paleozoic gas in the basin, after having a large-scale short migration in the range of source rocks, eventually gathered in the effective traps of the Ordovician weathering crust, and in the low permeability effective sand traps inside or near Carboniferous-Permian source rocks. The future risk exploration targets are: (1) for Mesozoic oil exploration, it will extend northward and explore unconventional reservoirs in source rocks; (2) for Upper Paleozoic gas exploration, it will extend southward and explore marine clastic gas reserviors; (3) for Lower Paleozoic gas exploration, it will search for lithologic-structural traps of carbonate weathering crust in the north-central and southeastern Yishan slope and those of carbonate reef flat. Key words: Ordos Basin, reservoir profile, petroleum system, risk exploratio

Xe-CT and transcranial doppler in symptomatic vasospasm subarachnoid hemorrhage patients under euvolemic treatment without sedation

Background : Delayed cerebral ischemia from cerebral arterial vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) is associated with significant morbidity and mortality. Early recognition of the cerebral arterial vasospasm and institution of appropriate treatment can reduce the consequences. Aim : We investigated the association of transcranial Doppler (TCD) and Xe-CT with the characteristics of symptomatic vasospasm secondary to aneurysmal subarachnoid hemorrhage (SAH) in patients who underwent euvolemic treatment without sedation. Materials and Methods : Data collected prospectively in patients with aSAH admitted to a neurocritical care unit in a regional hospital were retrospectively analyzed. Out of the 98 consecutive patients with aSAH, 30 patients underwent paired Xe-CT (not sedated) and TCD studies. Correlation between cortical cerebral blood flow (CBF) and mean blood flow velocity in middle cerebral artery (MCA) territories was analyzed. The lowest cortical regional CBF and MCA velocity were compared between patients with and without symptomatic vasospasm. Results : Symptomatic vasospasm occurred in 12 patients. No correlation was found between CBF and mean blood flow velocity of the MCA territory. The differences between MCA velocity and lowest cortical CBF in patients with symptomatic vasospasm were significantly different from patients without symptoms. Conclusion : TCD does not help to predict regional CBF in the MCA territory in patients with aSAH on euvolemic treatment

<i>Cunninghamia lanceolata</i> Canopy Relative Chlorophyll Content Estimation Based on Unmanned Aerial Vehicle Multispectral Imagery and Terrain Suitability Analysis

This study aimed to streamline the determination of chlorophyll content in Cunninghamia lanceolate while achieving precise measurements of canopy chlorophyll content. Relative chlorophyll content (SPAD) in the Cunninghamia lanceolate canopy were assessed in the study area using the SPAD-502 portable chlorophyll meter, alongside spectral data collected via onboard multispectral imaging. And based on the unmanned aerial vehicle (UAV) multispectral collection of spectral values in the study area, 21 vegetation indices with significant correlation with Cunninghamia lanceolata canopy SPAD (CCS) were constructed as independent variables of the model’s various regression techniques, including partial least squares regression (PLSR), random forests (RF), and backpropagation neural networks (BPNN), which were employed to develop a SPAD inversion model. The BPNN-based model emerged as the best choice, exhibiting test dataset coefficients of determination (R2) at 0.812, root mean square error (RSME) at 2.607, and relative percent difference (RPD) at 1.942. While the model demonstrated consistent accuracy across different slope locations, generalization was lower for varying slope directions. By creating separate models for different slope directions, R2 went up to about 0.8, showcasing favorable terrain applicability. Therefore, constructing inverse models with different slope directions samples separately can estimate CCS more accurately