7,674 research outputs found
Feasibility of Software-Based Duty Cycling of GPS for Trajectory-Based Services
Energy-efficient localization is increasingly important for many types of smartphone apps. The research community has argued that fixed duty cycling of GPS is not a good choice for trajectory-based services concerning route accuracy. In this paper, we describe the design and implementation of a highly accurate map matching and path construction algorithm. Furthermore, with thorough field experiments, we show that fixed duty cycling of a smartphone GPS receiver is a feasible approach for trajectory-based services, and it can achieve considerable energy conservation without sacrificing much route accuracy. When increasing the GPS sampling period beyond 120 seconds, it saves at least 78% energy in comparison to continuous GPS sampling, while the loss of route accuracy tends to be stable around 23%.Li, Xiaohan, Yuan, Fengpeng, & Lindqvist, Janne. (2016). Feasibility of Software-Based Duty Cycling of GPS for Trajectory-Based Services. In Proceedings of Consumer Communications & Networking Conference (CCNC2016-EdgeCom), Las Vegas, NV. http://ieeexplore.ieee.org/xpl/conhome.jsp?reload=true&punumber=1001153Peer reviewe
Differential Reactivity of Metal Binding Domains of Copper ATPases towards Cisplatin and Colocalization of Copper and Platinum
The Menkes (MNK) and Wilson (WLN) disease proteins are two P-type ATPases responsible for active Cu efflux. These ATPases are also associated with resistance to cisplatin. In this work, different metal-binding domains (MBDs) of ATPases (9 out of 12 domains) were compared based on their reactivity towards cisplatin. The reaction rates of the MBDs can be largely different; the reaction of MNK6 is about six times faster than that of WLN2. Copper coordination favors the platination of the MBDs to different extents. The rate of platination was generally greater for holo-MBDs than for apo-MBDS (particularly in the case of WLN4 and WLN2); however, it was negligibly affected in the case of MNK6. Interestingly, the platinum binding weakens the CuI coordination, but does not expel the copper ion from MBDs. The latter results nicely explain the inhibitory effect of Cu upon the cisplatin translocation promoted by Cu-ATPases and can help in understanding how copper levels can modulate the sensitivity of cancer cells to platinum chemotherapy
Tetrathiomolybdate inhibits the reaction of cisplatin with human copper chaperone Atox1
Cisplatin is a widely used anticancer drug in clinic, and ammonium tetrathiomolybdate ([(NH 4 ) 2 MoS 4 ], TM) is a copper chelator used in clinic for the treatment of Wilson's disease. Recently, TM has been found to enhance the therapeutic effect of cisplatin; however, the origin of this effect is not clear. Here we found that TM can inhibit the reaction of cisplatin with Cu-Atox1 and prevent the protein unfolding and aggregation induced by cisplatin. Although Ag(i) binds to Atox1 in a way similar to Cu(i)-Atox1, TM does not prevent the reaction of Ag-Atox1 with cisplatin. This result indicates that the formation of a Mo-centered trimeric protein cluster in the TM-Cu-Atox1 system plays a role in the inhibitory effect. This work provides new insights into the mechanism by which TM enhances the cytotoxic efficacy of cisplatin and helps to circumvent cisplatin resistance of tumor cells
Cisplatin reacts with histone H1 and the adduct forms a ternary complex with DNA
Cisplatin is an anticancer drug widely used in clinics; it induces the apoptosis of cancer cells by targeting DNA. However, its interaction with proteins has been found to be crucial in modulating the pre and post-target activity. Nuclear DNA is tightly assembled with histone proteins to form nucleosomes in chromatin; this can impede the drug to access DNA. On the other hand, the linker histone H1 is considered 'the gate to nucleosomal DNA' due to its exposed location and dynamic conformation; therefore, this protein can influence the platination of DNA. In this study, we performed a reaction of cisplatin with histone H1 and investigated the interaction of the H1/cisplatin adduct with DNA. The reactions were conducted on the N-terminal domains of H1.4 (sequence 1-90, H1 N90 ) and H1.0 (sequence 1-7, H1 N7 ). The results show that H1 readily reacts with cisplatin and generates bidentate and tridentate adducts, with methionine and glutamate residues as the preferential binding sites. Chromatographic and NMR analyses show that the platination rate of H1 is slightly higher than that of DNA and the platinated H1 can form H1-cisplatin-DNA ternary complexes. Interestingly, cisplatin is more prone to form H1-Pt-DNA ternary complexes than trans-oriented platinum agents. The formation of H1-cisplatin-DNA ternary complexes and their preference for cis- over trans-oriented platinum agents suggest an important role of histone H1 in the mechanism of action of cisplatin
Tian guo hua yuan
安徒生原著 ; 蔡慧冰改寫 ; 陳楠舟插圖.改寫自Andersen的Paradisets have.Antusheng yuan zhu ; Cai Huibing gai xie ; Chen Nanzhou cha tu
Raw data for Yuan et al., 2023, litter CNP concentration, JOE
Raw data for Yuan et al., 2023, Plant litter initial concentrations of C, N, and P. Any use of the dataset please email to the corresponding author at [email protected].</p
On My Way: Optimizing Driving Routes for Navigation Applications
Conventionally, the route recommendations given by GPS navigation applications have been considered as the optimal route search problem only between two locations - origin and destination. Sometimes people want to visit several intermediate locations prior to reaching their final destination. For example, travelers may want to visit a diner and a gas station before arriving at their vacation destination. Although there is likely to be many choices that are available along the route to the destination, only one place from each type should be chosen. Furthermore, in new emerging application domains, such as “physical-world crowdsourcing”, people may want to opportunistically visit some places in order to complete personal or work related tasks. Our work explores a design space where we try to reduce the amount of requests made to third-party map and route data providers. We explore the simple idea of using the Euclidean distance as a rough estimate for the optimal route between destinations with multiple waypoints. Our preliminary results indicate that with over 80% of test cases, this simple Euclidean distance estimator approach gives at least one optimal routing alternative.Yuan, Fengpeng, Song, Xueyuan & Lindqvist, Janne. (2016). On My Way: Optimizing Driving Routes for Navigation Applications. In Proceedings of Consumer Communications & Networking Conference (CCNC2016-EdgeCom), Las Vegas, NV. http://ieeexplore.ieee.org/xpl/conhome.jsp?reload=true&punumber=1001153Peer reviewe
F NMR Allows the Investigation of the Fate of Platinum(IV) Prodrugs in Physiological Conditions
PtIV prodrugs can overcome resistance and side effects of conventional PtII anticancer therapies. By 19 F-labeling of a PtIV prodrug (Pt-FBA, FBA=p-fluorobenzoate), the activation under physiological conditions could be investigated. Unlike single-electron reductants, multi-electron agents can efficiently promote the two electrons reduction of PtIV to PtII . The activation of Pt-FBA in cell lysate is highly dependent upon the type of cancer cells. When administered to E. coli, Pt-FBA is reduced intracellularly and free FBA can shuttle out of the cell. The reduction rate greatly increases by inducing metallothionein overexpression and is lowered by addition of ZnII ions. When injected into mice, Pt-FBA undergoes fast reduction in the bloodstream accompanied by metabolic degradation of FBA; nevertheless, unreduced Pt-FBA can accumulate to detectable levels in liver and kidneys. The 19 F NMR approach has the advantage of avoiding the interference of all background signals
Introduction to the Song-Yuan-Ming Transition in Chinese History
Abridged translation of my \u27Introduction\u27 to The Song-Yuan-Ming Transition in Chinese History by Zhang Yi. -- author-supplied description
Tunable acoustic attenuation in dilute suspensions of non-spherical magnetic particles
The microstructure of suspensions of ferromagnetic particles with subwavelength size can be controlled by an external field, making it possible to develop novel broadband acoustic materials with anisotropic and tunable acoustic properties. In this study we experimentally show that dilute suspensions of nickel micro-flakes exhibit a greater than 20% change in attenuation coefficient at MHz frequencies upon changing the direction of an external magnetic field, at particle volume fractions of only 0.5%. Optical transmission measurements and analysis of the characteristic timescales of particle alignment and chaining are used to study the mechanisms behind this acoustic anisotropy. By making comparison to suspensions of spherical particles, we show that the shape and orientation of the nickel micro-flakes play important roles in the tunable acoustic attenuation of these suspensions.Peer reviewed
- …
