Color Filtering Localization for Three-Dimensional Underwater Acoustic Sensor Networks

Accurate localization for mobile nodes has been an important and fundamental problem in underwater acoustic sensor networks (UASNs). The detection information returned from a mobile node is meaningful only if its location is known. In this paper, we propose two localization algorithms based on color filtering technology called PCFL and ACFL. PCFL and ACFL aim at collaboratively accomplishing accurate localization of underwater mobile nodes with minimum energy expenditure. They both adopt the overlapping signal region of task anchors which can communicate with the mobile node directly as the current sampling area. PCFL employs the projected distances between each of the task projections and the mobile node, while ACFL adopts the direct distance between each of the task anchors and the mobile node. Also the proportion factor of distance is proposed to weight the RGB values. By comparing the nearness degrees of the RGB sequences between the samples and the mobile node, samples can be filtered out. And the normalized nearness degrees are considered as the weighted standards to calculate coordinates of the mobile nodes. The simulation results show that the proposed methods have excellent localization performance and can timely localize the mobile node. The average localization error of PCFL can decline by about 30.4% than the AFLA method.Comment: 18 pages, 11 figures, 2 table

On a Generalised Typicality and Its Applications in Information Theory

Typicality lemmas have been successfully applied in many information theoretical problems. The conventional strong typicality is only defined for finite alphabets. Conditional typicality and Markov lemmas can be obtained for strong typicality. Weak typicality can be defined based on a measurable space without additional constraints, and can be easily defined based on a general stochastic process. However, to the best of our knowledge, no conditional typicality or strong Markov lemmas have been obtained for weak typicality in classic works. As a result, some important coding theorems can only be proved by strong typicality lemmas and using the discretisation-and-approximation-technique. In order to solve the aforementioned problems, we will show that the conditional typicality lemma can be obtained for a generic typicality. We will then define a multivariate typicality for general alphabets and general probability measures on product spaces, based on the relative entropy, which can be a measure of the relevance between multiple sources. We will provide a series of multivariate typicality lemmas, including conditional and joint typicality lemmas, packing and covering lemmas, as well as the strong Markov lemma for our proposed generalised typicality. These typicality lemmas can be used to solve source and channel coding problems in a unified way for finite, continuous, or more general alphabets. We will present some coding theorems with general settings using the generalised multivariate typicality lemmas without using the discretisation-and-approximation technique. Generally, the proofs of the coding theorems in general settings are simpler by using the generalised typicality, than using strong typicality with the discretisation-and-approximation technique

An atypical case of autochthonous cutaneous leishmaniasis associated with naturally infected phlebotomine sand flies in Texas, United States

In the United States, phlebotomine sand flies carrying Leishmania (Leishmania) mexicana are endemic along the southern border. However, relatively little is known about the enzootic and zoonotic transmission of L. (L.) mexicana within the United States, and autochthonous cases of the consequent disease are rarely reported. We investigated an atypical case of cutaneous leishmaniasis (CL) caused by L. (L.) mexicana in a patient from central Texas which did not respond to a typical antileishmanial chemotherapy. We also investigated sand fly vectors around the patient's residence. PCR followed by DNA sequencing was used for determination of Leishmania spp., sand fly species, and host blood meal source. The L. (L.) mexicana genotype from the patient was identical to one found in a positive sand fly. Moreover, this genotype presented the same single-nucleotide polymorphisms as other historical CL cases acquired in Texas over the last 10 years, but distinct from those originating in Mexico and Central America. Three sand fly species were identified among the samples analyzed (n = 194), the majority of which were Lutzomyia (Dampfomyia) anthophora (n = 190), of which four specimens tested positive for Leishmania and two blood-fed specimens showed the presence of a human blood meal. This study highlights the complexity of clinical management of CL in a setting where the disease is infrequently encountered. The detection of human blood in Lu. (D.) anthophora is the first documentation of anthropophagy in this species. This is the first report of wild-caught, naturally infected sand flies found in association with an autochthonous case of human leishmaniasis and the specific strain of Leishmania (Leishmania) mexicana in the United States. Copyright © 2020 by The American Society of Tropical Medicine and Hygien

Detrital zircon U–Pb geochronology from the Upper Carboniferous sediments of Benxi Formation in the North China Craton: implications for tectonic-sedimentary evolution

The provenance of the Upper Carboniferous Benxi Formation in North China Craton (NCC) has been considered as the northern margin of the NCC, not the North Qinling Orogenic Belt. To understand the provenance and the tectonic-sedimentary evolution during the sedimentary period of the Benxi Formation, the zircon U–Pb geochronology analysis was conducted on eleven clastic sandstone samples. The south of the NCC received clastic sediments from the North Qinling Orogenic Belt. The orogenic movements around the NCC in the Late Carboniferous period had significant impacts on the changes in paleotopography. During the early sedimentary period of the Hutian member of the Benxi Formation, the north of the Qinling Orogenic Belt was rapidly uplifted, and paleotopography was south-uplifting and north-dipping; thus, the clastic source was the North Qinling Orogenic Belt. From the late sedimentary period of the Benxi Formation Hutian member to the sedimentary period of the Jinci member, paleotopography was reversed. The northern margin of the NCC quickly uplifted, and paleotopography was north-uplifting and south-dipping. Two distinct provenances were present in the sediments of the Benxi Formation. The sediments were supplied predominately by the provenance in the north

Detrital zircon U–Pb geochronology from the Upper Carboniferous sediments of Benxi Formation in the North China Craton: implications for tectonic-sedimentary evolution

The provenance of the Upper Carboniferous Benxi Formation in North China Craton (NCC) has been considered as the northern margin of the NCC, not the North Qinling Orogenic Belt. To understand the provenance and the tectonic-sedimentary evolution during the sedimentary period of the Benxi Formation, the zircon U–Pb geochronology analysis was conducted on eleven clastic sandstone samples. The south of the NCC received clastic sediments from the North Qinling Orogenic Belt. The orogenic movements around the NCC in the Late Carboniferous period had significant impacts on the changes in paleotopography. During the early sedimentary period of the Hutian member of the Benxi Formation, the north of the Qinling Orogenic Belt was rapidly uplifted, and paleotopography was south-uplifting and north-dipping; thus, the clastic source was the North Qinling Orogenic Belt. From the late sedimentary period of the Benxi Formation Hutian member to the sedimentary period of the Jinci member, paleotopography was reversed. The northern margin of the NCC quickly uplifted, and paleotopography was north-uplifting and south-dipping. Two distinct provenances were present in the sediments of the Benxi Formation. The sediments were supplied predominately by the provenance in the north

Characterization of Anti-bacterial Compounds from the Seed Coat of Chinese Windmill Palm Tree (Trachycarpus fortunei)

The increasing of multidrug resistance in bacterial associated infections has impaired the current antimicrobial therapy and it forces the search for other alternatives. In this study, we aimed to find the in vitro antibacterial activity of seed coat of Trachycarpus fortunei against a panel of clinically important bacterial species. Ethanolic extracts of target tissues were fractionated through macro porous resin by column chromatography, using ethanol as an organic solvent with a concentration gradient of 0–100%, each along with 20% concentration increment. The minimum inhibitory (MIC) concentrations of all fractions were measured. It is found that 20% ethanolic fraction showed the most significant inhibition against tested bacterial species. All fractions were analyzed by Ultra-Performance Liquid Chromatography/mass spectrometry (UPLC/MS) and compounds were identified by comparing mass spectra with standard libraries. By pairing the identified compounds from different fractions with the antibacterial activity of each fraction, it was shown that compounds stearamide (7), 1-(4-Fluorophenyl)-2-(methylthio)-1H-imidazole-5-carboxylic acid (9) and 2,4,5 triacetoxybiphenyl (10) topped in the list for anti-bacterial activity. Further experiment with pure chemicals verified that compounds 9 and 10 have antibacterial activity against Gram-negative bacteria. Whereas, the lowest MIC value (39.06 μg/mL) was obtained by compound 10 against Staphylococcus epidermidis. Hence, the seed coat of T. fortunei with its antimicrobial spectrum could be a good candidate for further bactericidal research

Enhancing Small-Cell Capacity with Wireless Backhaul

Recently, hyperdense small cells have been proposed to meet the challenge of the tremendous increment in cellular data service requirements. To reduce the deployment cost, as well as operated cost, these small cells are usually connected to limited backhauls, in which case the backhaul capacity may become a bottleneck in busy hours. In this paper, we propose an optimal scheme for the small cells to utilize the macrocell links as its wireless backhaul. Based on stochastic geometry, the analytical expressions of network capacity with in-band and out-band wireless backhaul are derived and validated using simulation results. The optimized results show that our proposed scheme can significantly improve the network performance in scenarios with a high traffic load

On the capacity region of the semideterministic Z channel

Abstract—We study a class of discrete memoryless Z channels, where there are some deterministic components in the channel configuration. We call this channel the semi-deterministic Z channel. We first provide an outer bound on the capacity region. Then the known achievable rate region for the general Z channel is specialized to the semi-deterministic case. Noting the similarity between the inner and outer bounds, we identify special classes of semi-deterministic Z channels where the two bounds coincide and therefore establish their capacity regions. Index Terms—semi-deterministic Z channel, capacity region