Anomalies of the omnipresent earth magnetic (i.e., geomagnetic) field in an indoor environment, caused by local disturbances due to construction materials, give rise to noisy direction sensing that hinders any dead reckoning system. In this paper, we turn this unpalatable phenomenon into a favorable one. We present Magicol, an indoor localization and tracking system that embraces the local disturbances of the geomagnetic field. We tackle the low discernibility of the magnetic field by vectorizing consecutive magnetic signals on a per-step basis, and use vectors to shape the particle distribution in the estimation process. Magicol can also incorporate WiFi signals to achieve much improved positioning accuracy for indoor environments with WiFi infrastructure. We perform an in-depth study on the fusion of magnetic and WiFi signals. We design a two-pass, bidirectional particle filtering process for maximum accuracy, and propose an on-demand WiFi scan strategy for energy savings. We further propose a compliant-walking method for location database construction that drastically simplifies the site survey effort. We conduct extensive experiments at representative indoor environments, including an office building, an underground parking garage, and a supermarket in which Magicol achieved a 90 percentile localization accuracy of 5m, 1m, and 8m, respectively, using the magnetic field alone. The fusion with WiFi leads to 90 percentile accuracy of 3.5m for localization and 0.9m for tracking in the office environment. When using only the magnetism, Magicol consumes 9× less energy in tracking compared to WiFibased tracking.

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TaGW2, an orthologous gene of rice OsGW2, has been associated with kernel width and weight of bread wheat (Triticum aestivum). Difference in TaGW2 coding sequence was not found among different wheat varieties in previous researches. In this study, we found eight exons and seven introns in TaGW2 with a full-length cDNA sequence of 1,275 bp, which contains a conserved function domain and seven splice sites that shared homology with rice OsGW2. A single T-base insertion in the eighth exon of TaGW2 on chromosome 6A was detected in a large-kernel wheat variety, Lankaodali. This insertion mutation reduces the coding protein sequence from normal 424 amino acids (~47.2 kDa) to 328 amino acids (~37.1 kDa) by truncating 96 amino acids. The result was validated by identifying histidine-tagged TaGW2 proteins encoded by both alleles of the mutant and the wild types in SDS-PAGE. Allele-specific PCR markers were developed based on the single nucleotide polymorphism (SNP) site. The SNP markers were genotyped for an F(2) segregation population from the cross of Lankaodali × Chinese Spring. Seed traits of F(2:3) families were evaluated in three different environments. The association analysis indicated that F(2:3) families with the mutated TaGW2 allele significantly increased kernel width (KW) and thousand-kernel weight (TKW), and slightly improved kernel length (KL). Using the SNP markers, another two varieties harbored the mutated TaGW2 allele were successfully identified from 22 additional wheat varieties, and they both have large KW and TKW. Cloning and sequencing of the gene further confirmed the functions of the mutated allele of TaGW2 in the two large kernel varieties. The results suggested that TaGW2 may negatively regulate kernel size variation, which shares the same function as OsGW2 in rice. The successful development of SNP markers provides a useful tool for improving kernel yield in wheat.

The anti-malarial agent dihydroartemisinin (DHA) has strong anti-angiogenic activity. This study aimed to investigate the molecular mechanism underlying this effect of DHA on angiogenesis. We found that DHA shows a dose-dependent inhibition of proliferation and migration of in HUVECs. DHA specifically down-regulates the mRNA and protein expression of VEGFR2 in endothelial cells. Treatment with DHA increases IκB-α protein and blocks nuclear translocation of NF-κB p65. In addition, DHA directly regulates VEGFR2 promoter activity through p65 binding motif, and decreases the binding activity of p65 and VEGFR2 promoter, suggesting defective NF-κB signaling may underlie the observed effects of DHA on VEGFR2 expression. In the presence of the NF-κB inhibitor PDTC, DHA could not further repress VEGFR2. Co-treatment with PDTC and DHA produced minimal changes compared to the effects of either drug alone in in vitro angiogenesis assays. Similar findings were found in vivo through a mouse retinal neovascularization model examining the effects of PDTC and DHA. Our data suggested that DHA inhibits angiogenesis largely through repression of the NF-κB pathway. DHA is well tolerated, and therefore may be an ideal candidate to use clinically as an angiogenesis inhibitor for cancer treatment.

Unique hollow hybrid structures composed of well-dispersed catalyst nanoparticles embedded in a carbon matrix offer great advantages for constructing advanced supported catalysts. Herein, we report the designed synthesis of Co9S8 and nitrogen doped hollow carbon sphere (Co9S8/NHCS) composites by carbonization of metanilic anions within the confinement of the two-dimensional galleries of hollow spherical cobalt-aluminum layered double hydroxides. The Co9S8/NHCS are composed of numerous porous carbon nanoflakes, and monodisperse Co9S8 nanoparticles are embedded within the carbon nanoflakes. Electrochemical measurements show the Co9S8/NHCS catalysts prepared at 900 °C exhibit superior oxygen reduction reaction (ORR) activity, resulting in the highest ORR performance to date among all transition metal sulfide-based ORR catalysts in both alkaline and acid electrolytes. This interlayer confined reaction approach may provide an efficient platform for the synthesis of other functional materials for alternative applications.Monodisperse Co 9 S 8 nanoparticles embedded within nitrogen-doped porous carbon nanoflakes are synthesized by an interlayer confined reaction and exhibit excellent oxygen reduction reaction activity.

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Clock synchronization is critical for Wireless Sensor Networks (WSNs) due to the need of inter-node coordination and collaborative information processing. Although many message passing protocols can achieve satisfactory clock synchronization accuracy, they incur prohibitively high overhead when the network scales to more than tens of nodes. An alternative approach is to take advantage of the global time reference induced by existing infrastructures including GPS, timekeeping radio stations, or power grid. However, high power consumption and geographic constraints present them from being widely adopted in WSNs. In this paper, we propose ROCS, a new clock synchronization approach exploiting the Radio Data System (RDS) of FM radios. First, we design a new hardware FM receiver that can extract a periodic pulse from FM broadcasts, referred to as RDS clock. We then conduct a large-scale measurement study of RDS clock in our lab for a period of six days and on a vehicle driving through a metropolitan area of over 40 km 2 . Our results show that RDS clock is highly stable and hence is a viable means to calibrate the clocks of large-scale city-wide sensor networks. To reduce the high power consumption of FM receiver, ROCS intelligently predicts the time error due to drift, and adaptively calibrates the native clock via the RDS clock. We implement ROCS in TinyOS on our hardware FM receiver and a TelosB-compatible WSN platform. Our extensive experiments using a 12-node testbed and our driving measurement traces show that ROCS achieves accurate and precise clock synchronization with low power consumption.