Studies have shown that many behavioral decisions of fish are facilitated by the lateral line system which provides hydrodynamic information about the surrounding fluid. Inspired by the functionality ...of the system, a distributed pressure sensory system is developed. The system is intended for use on autonomous underwater vehicles to aid station keeping and accurate maneuvering by allowing the vehicle to react to the changes in the fluid environment before they result in body perturbation. The system can also be used for mission level decision making such as obstacle detection. This paper presents a prototype sensory system using differential, as opposed to absolute or gauge, pressure sensors as the sensing elements, which allows for higher measurement precision. Experimental tests are designed to characterize the system's ability to estimate the hydrodynamic force and to detect the presence of a wall. The hydrodynamic force estimated by the system is validated with an independent force measuring apparatus. The impending wall could also be detected by analyzing the pressure distribution obtained from the sensory system. Particularly, it is found that the wall distance and angle may be inferred by comparing the amplitude and phase of the Fourier components in the pressure distribution against those without the obstacle.
In thermodynamics, the one-electron reduction of O2 by the conduction band electrons of Bi2WO6 or WO3 is not allowed. However, many studies have reported that Bi2WO6 is photocatalytically active for ...organic degradation in aerated aqueous suspension. In this work, the photocatalytic activities of Bi2WO6 and WO3 under visible light have been compared by using phenol degradation as a model reaction. In aerated aqueous solution, Bi2WO6 and WO3 were indeed active and inactive, respectively, as reported. However, by using Pt as a catalyst for O2 reduction, or by using H2O2 as an electron scavenger, Bi2WO6 became much less active than WO3. Similar results were also obtained in the production of H2O2 under visible light, and in the generation of •OH radicals under UV light, measured by a spin-trapping electron paramagnetic resonance (EPR) spectroscopy. Moreover, in the presence of catalase to completely remove H2O2, the EPR signal due to •OH radical was reduced, but not disappeared. These observations indicate that the irradiated Bi2WO6 is not only active for water oxidation to •OH but also active for the two-electron reduction of O2 to H2O2, the latter of which hardly occurs with the irradiated WO3.
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IJS, KILJ, NUK, PNG, UL, UM
The NLRP3 inflammasome is a multiprotein complex that plays a pivotal role in regulating the innate immune system and inflammatory signaling. Upon activation by PAMPs and DAMPs, NLRP3 oligomerizes ...and activates caspase-1 which initiates the processing and release of pro-inflammatory cytokines IL-1β and IL-18. NLRP3 is the most extensively studied inflammasome to date due to its array of activators and aberrant activation in several inflammatory diseases. Studies using small molecules and biologics targeting the NLRP3 inflammasome pathway have shown positive outcomes in treating various disease pathologies by blocking chronic inflammation. In this review, we discuss the recent advances in understanding the NLRP3 mechanism, its role in disease pathology, and provide a broad review of therapeutics discovered to target the NLRP3 pathway and their challenges.
Various factors that influence the photocatalytic activity of TiO2 for organic degradation in aerated aqueous solution have been reported. For instance, anatase is considered to be much more active ...than rutile. However, no attention has been paid to the difference in their sorption capacities toward O2 in water, which might be critical to the activity determination. In this work, Ag+ has been used as an electron scavenger, for the photocatalytic degradation of 4-chlorophenol in the N2-purged aqueous suspension of TiO2 under UV light. Three different TiO2 samples in the crystal forms of anatase and rutile, containing micro- and mesopores, were prepared, followed by sintering at different temperatures (T s). The initial rate of 4-chlorophenol photodegradation, per the initial amount of Ag+ adsorbed, increased exponentially with T s. Such T s-dependent normalized rates were observed with three differently prepared TiO2 samples, and three curves were almost overlapped. Comparatively, in the aerated aqueous suspension of TiO2, the initial rate of 4-chlorophenol photodegradation, per surface area of the catalyst, first increased and then decreased with T s, the trend similar to those widely reported. Moreover, from the literature data of water photosplitting over TiO2, the initial rate of O2 evolution, per the initial amount of Ag+ adsorbed, increased exponentially with T s. Evidence clearly shows that with the same amount of electron scavenger on the catalyst surfaces, anatase and rutile actually have a similar photocatalytic activity at a given T s, for organic degradation or water oxidation. It is recommended that to evaluate the photocatalytic activities of different TiO2 samples in an aerated aqueous solution, the difference in O2 adsorption needs to be taken into account.
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Cancer is the second leading cause of mortality, only overcome by cardiovascular diseases, and has caused more than 8.7 million deaths in 2015 all over the world. This figure is expected to rise to ...about 13.1 million by 2030. In order to prevent or cure this fatal illness, substantial efforts have been devoted to develop and discover new anticancer drugs with same or better antitumor activity but lesser toxicity. Matrine is an alkaloid isolated from Sophora flavescens Ait. For decades, matrine and its derivatives have been studied as antineoplastic agents which predominantly work by inhibiting proliferation and inducing apoptosis of cancer cells. The mechanism responsible for the anticancer activity of matrine can be recognized via up-regulating or down-regulating expression of the cancer related molecules, eventually causing tumor cell death. This review summarizes research developments of matrine and its derivatives as anticancer agents. A few possible research directions, suggestions and clues for future work on the development of novel matrine-based anticancer agents with improved expected activities and lesser toxicity have also been provided.
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•Cancer is the second leading cause of mortality worldwide, only overcome by cardiovascular diseases.•Cancer-related deaths are expected to increase to 13.1 million by 2030.•Matrine (C15H24N2O) is an alkaloid found in plants from the genus Sophora.•Matrine and its derivatives have been studied as antineoplastic agents which predominantly work by inhibiting proliferation and inducing apoptosis of cancer cells.•Matrine synergistically enhance the efficacy of chemotherapy when it is used in combination with other anticancer drugs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Brookite is the least studied TiO2, and its photocatalytic activity higher or lower than that of anatase still remains unclear. In this work, three different model reactions have been used for the ...activity assessment. Phase-pure brookite and anatase were homemade at different temperatures (T s = 200–500 °C), as confirmed by X-ray diffraction and Raman spectroscopy. For phenol oxidation in aerated aqueous solution, brookite showed an apparent activity higher and lower than that of anatase at low and high T s, respectively. For chromate reduction in aerated aqueous suspension, the apparent activity of brookite was always lower than that of anatase. However, with the same amount of Cr(VI) or Ag(I) adsorbed on the oxide in water for Cr(VI) reduction or for phenol degradation under N2, the intrinsic activities of brookite and anatase not only became similar at given T s but also increased with the increase of T s. Moreover, for O2 reduction to H2O2 in the presence of excess phenol, the BET surface area normalized activity of brookite was always higher than that of anatase, the trend of which was similar to that observed from phenol degradation in aerated aqueous solution. It is proposed that brookite has a stronger affinity to O2 in water than anatase. Then, the observed difference between brookite and anatase in the apparent photocatalytic activity for phenol degradation is ascribed to the combined effect of T s, surface area, and sorption capacity toward the dissolved O2 in water.
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Abstract
Permafrost dynamics can drastically affect vegetation and soil carbon dynamics in northern high latitudes. Vegetation has significant influences on the energy balance of soil surface by ...impacting the short-wave radiation, long-wave radiation and surface sensible heat flux, affecting soil thermal dynamics, in turn, inducing vegetation shift, affecting carbon cycling. During winter, snow can also significantly impact soil temperature due to its insulative effect. However, these processes have not been fully modeled to date. To quantify the interactions between vegetation, snow, and soil thermal dynamics and their impacts on carbon dynamics over the circumpolar region (45–90° N), we revise a sophisticated ecosystem model to improve simulations of soil temperature profile and their influences on vegetation, ecosystem carbon pools and fluxes. We find that, with warmer soil temperature in winter and cooler soil temperature in summer simulated with the revised model considering vegetation shift and snow effects, the region will release 1.54 Pg C/year to the atmosphere for present-day and 66.77–87.95 Pg C in 2022–2100. The canopy effects due to vegetation shift, however, will get more carbon sequestered into the ecosystem at 1.00 Pg C/year for present day and 36.09–44.32 Pg C/year in 2022–2100. This study highlights the importance to consider the interactions between snow, vegetation shift and soil thermal dynamics in simulating carbon dynamics in the region.
We extend and explore the general non-relativistic effective theory of dark matter (DM) direct detection. We describe the basic non-relativistic building blocks of operators and discuss their ...symmetry properties, writing down all Galilean-invariant operators up to quadratic order in momentum transfer arising from exchange of particles of spin 1 or less. Any DM particle theory can be translated into the coefficients of an effective operator and any effective operator can be simply related to most general description of the nuclear response. We find several operators which lead to novel nuclear responses. These responses differ significantly from the standard minimal WIMP cases in their relative coupling strengths to various elements, changing how the results from different experiments should be compared against each other. Response functions are evaluated for common DM targets - F, Na, Ge, I, and Xe - using standard shell model techniques. We point out that each of the nuclear responses is familiar from past studies of semi-leptonic electroweak interactions, and thus potentially testable in weak interaction studies. We provide tables of the full set of required matrix elements at finite momentum transfer for a range of common elements, making a careful and fully model-independent analysis possible. Finally, we discuss embedding non-relativistic effective theory operators into UV models of dark matter.
NNNifty targets: In a straightforward copper‐mediated synthesis of 1,4‐disubstituted and 1,4,5‐trisubstituted 1,2,3‐triazoles, readily available aniline and N‐tosylhydrazone substrates underwent ...cyclization through CN and NN bond formation (see scheme; Piv=pivaloyl, Ts=p‐toluenesulfonyl). This method enables the preparation of 1,2,3‐triazoles with high efficiency under mild conditions without the use of azides.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
It is believed that the lateral line found in most fish and some other aquatic organisms plays an important role in many behaviors by providing hydrodynamic information about the surrounding fluid. ...This paper presents a lateral line inspired feedforward control design for the autonomous underwater vehicles. The goal of this paper is to improve maneuvering accuracy for underwater exploration and environmental monitoring. The proposed controller takes pressure measurements at multiple locations over the entire vehicle hull and forms a B-spline surface approximation of the pressure distribution. Hydrodynamic forces acting on the vehicle are then estimated and passed to the controller for the improved trajectory tracking performance. The algorithm is formulated in such a way that the force estimation is a linear, fixed weight combination of the pressure signals, which enables rapid online computation. The performance of the feedforward controller is simulated in conjunction with the "robust integral of the sign of the error" control design. Trajectory tracking is investigated for control accuracy in the presence of localization errors. Reduced tracking errors are observed with the feedforward design. Experimental tests with pressure sensors on a moving cylinder further vindicate the force estimation algorithm.
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