In this study, visual recognition with a charge-coupled device (CCD) image feedback control system was used to record the movement of a coplanar XXY stage. The position of the stage is fedback ...through the image positioning method, and the positioning compensation of the stage is performed by the image compensation control parameter. The image resolution was constrained and resulted in an average positioning error of the optimized control parameter of 6.712 µm, with the root mean square error being 2.802 µm, and the settling time being approximately 7 s. The merit of a long short-term memory (LSTM) deep learning model is that it can identify long-term dependencies and sequential state data to determine the next control signal. As for improving the positioning performance, LSTM was used to develop a training model for stage motion with an additional dial indicator with an accuracy of 1 μm being used to record the XXY position information. After removing the assisting dial indicator, a new LSTM-based XXY feedback control system was subsequently constructed to reduce the positioning error. In other words, the morphing control signals are dependent not only on time, but also on the iterations of the LSTM learning process. Point-to-point commanded forward, backward and repeated back-and-forth repetitive motions were conducted. Experimental results revealed that the average positioning error achieved after using the LSTM model was 2.085 µm, with the root mean square error being 2.681 µm, and a settling time of 2.02 s. With the assistance of LSTM, the stage exhibited a higher control accuracy and less settling time than did the CCD imaging system according to three positioning indices.
Despite broad interest in using payment for ecosystem services to promote changes in the use of natural capital, there are few expost assessments of impacts of payment for ecosystem services programs ...on ecosystem service provision, program cost, and changes in livelihoods resulting from program participation. In this paper, we evaluate the Paddy Land-to-Dry Land (PLDL) program in Beijing, China, and associated changes in service providers’ livelihood activities. The PLDL is a land use conversion program that aims to protect water quality and quantity for the only surface water reservoir that serves Beijing, China’s capital city with nearly 20 million residents. Our analysis integrates hydrologic data with household survey data and shows that the PLDL generates benefits of improved water quantity and quality that exceed the costs of reduced agricultural output. The PLDL has an overall benefit–cost ratio of 1.5, and both downstream beneficiaries and upstream providers gain from the program. Household data show that changes in livelihood activities may offset some of the desired effects of the program through increased expenditures on agricultural fertilizers. Overall, however, reductions in fertilizer leaching from land use change dominate so that the program still has a positive net impact on water quality. This program is a successful example of water users paying upstream landholders to improve water quantity and quality through land use change. Program evaluation also highlights the importance of considering behavioral changes by program participants.
Over the past decade, numerous studies have attempted to enhance the effectiveness of radiotherapy (external beam radiotherapy and internal radioisotope therapy) for cancer treatment. However, the ...low radiation absorption coefficient and radiation resistance of tumors remain major critical challenges for radiotherapy in the clinic. With the development of nanomedicine, nanomaterials in combination with radiotherapy offer the possibility to improve the efficiency of radiotherapy in tumors. Nanomaterials act not only as radiosensitizers to enhance radiation energy, but also as nanocarriers to deliver therapeutic units in combating radiation resistance. In this review, we discuss opportunities for a synergistic cancer therapy by combining radiotherapy based on nanomaterials designed for chemotherapy, photodynamic therapy, photothermal therapy, gas therapy, genetic therapy, and immunotherapy. We highlight how nanomaterials can be utilized to amplify antitumor radiation responses and describe cooperative enhancement interactions among these synergistic therapies. Moreover, the potential challenges and future prospects of radio-based nanomedicine to maximize their synergistic efficiency for cancer treatment are identified.
Light (anti-)nuclei in relativistic heavy-ion collisions are considered to be formed by the coalescence mechanism of (anti-)nucleons in the present work. Using a dynamical phase-space coalescence ...model coupled with a multi-phase transport (AMPT) model, we explore the formation of light clusters such as deuteron, triton and their anti-particles in different centralities for
197
Au +
197
Au collisions at
s
NN
=
39
GeV. The calculated transverse momentum spectra of protons, deuterons, and tritons are comparable to those of experimental data from the RHIC-STAR collaboration. Both coalescence parameters
B
2
for (anti-)deuteron and
B
3
for triton increase with the transverse momentum as well as the collision centrality, and they are comparable with the measured values in experiments. The effect of system size on the production of light nuclei is also investigated by
10
B +
10
B,
16
O +
16
O,
40
Ca +
40
Ca, and
197
Au +
197
Au systems in central collisions. The results show that yields of light nuclei increase with system size, while the values of coalescence parameters present an opposite trend. It is interesting to see that the system size, as well as the centrality dependence of
B
A
(
A
= 2, 3), falls into the same group, which further demonstrates production probability of light nuclei is proportional to the size of the fireball. Furthermore, we compare our coalescence results with other models, such as the thermal model and analytic coalescence model, it seems that the description of light nuclei production is consistent with each other.
The newly discovered topological crystalline insulators feature a complex band structure involving multiple Dirac cones1, 2, 3, 4, 5, 6, and are potentially highly tunable by external electric field, ...temperature or strain. Theoretically, it has been predicted that the various Dirac cones, which are offset in energy and momentum, might harbour vastly different orbital character7. However, their orbital texture, which is of immense importance in determining a variety of a material's properties8, 9, 10 remains elusive. Here, we unveil the orbital texture of Pb1-xSnxSe, a prototypical topological crystalline insulator. By using Fourier-transform scanning tunnelling spectroscopy we measure the interference patterns produced by the scattering of surface-state electrons. We discover that the intensity and energy dependences of the Fourier transforms show distinct characteristics, which can be directly attributed to orbital effects. Our experiments reveal a complex band topology involving two Lifshitz transitions11 and establish the orbital nature of the Dirac bands, which could provide an alternative pathway towards future quantum applications.
Transform rotary motion triggered by environmental mechanical energy (e.g., wind) to electrical energy is widely used for energy harvesting. Triboelectric nanogenerators that are used to harvest ...rotational mechanical energy are mostly based on in-plane sliding or free-standing mode. However, the relative friction between the two contacting triboelectric layers may cause severe abrasion, which reduces the durability of the device and increases the maintenance cost. In this study, we report a combination of a cam and a movable frame for a novel triboelectric nanogenerator (CMF-TENG), which is expected to reduce the abrasion problem and improve the output performance. The cam is designed to transform the rotational motion triggered by ambient mechanical energy to linear movement of the movable frame, leading to a contact-separation of the triboelectric layers within each sub-triboelectrification unit of CMF-TENG, thus electric output can be generated. The average electric output from one subunit of the CMF-TENG achieved around 200 V of open-circuit voltage, 2.9 μA of short-circuit current, and 96 nC of transferred charge at the triggered rotational speed of 60 rpm. The power output increase from 180 μW (1 subunit) to around 728 μW when three subunits were connected in parallel. The output voltage of the CMF-TENG remained almost consistent throughout the roughly 8 h continuously operation, suggesting outstanding robustness and durability of the CMF-TENG. The CMF-TENG harvest energy from wind can light up 113 blue LEDs connected in series at a wind speed of 13.9 m/s with the assistance of a rectifying circuit; and can power a thermometer at the same wind speed condition with the assistance of a rectifying circuit and a capacitor. The results imply that the CMF-TENG can not only be used to harvest energy from the ambient environment, but also can achieve self-powered sensing. Technically, by using this novel design, additional sub-triboelectrification units can be added to improve the electric output of the entire device and the rotational mechanical energy can be harvested more effectively with less abrasion.
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In this work, we present a simple, practical and well-sealed design for converting rotational motion into linear motion, which can convert captured kinetic energy into electrical energy for powering small sensors in different environments:•CMF-TENG can be seen from the average current output peak that the output of the CMF-TENG signal increases steadily with the increase of the rotational speed, and each sub-triboelectrification unit of CMF-TENG has a stable electrical output.•It works in contact-separation mode and does not require spring assist. The output voltage of the CMF -TENG does not exhibit any measurable decay although this output has been continuously generated through more than 86,400 cycles (8 h). So, it has a good robustness.•In this structure, more power generation units can be added in theory, and a new structure is proposed for realizing a stable multi-layer energy harvesting device. It has shown potential applications in wireless environmental monitoring networks.
Background
Parkinson's disease (PD) features the motor control deficits resulting from irreversible, progressive degeneration of dopaminergic (DA) neurons of the nigrostriatal pathway. Although ...intracerebral transplantation of human fetal ventral mesencephalon (hfVM) has been proven effective at reviving DA function in the PD patients, this treatment is clinically limited by availability of hfVM and the related ethical issues. Homologous tissues to hfVM, such as porcine fetal ventral mesencephalon (pfVM) thus present a strong clinical potential if immune response following xenotransplantation could be tamed. Olfactory ensheathing cells (OECs) are glial cells showing immunomodulatory properties. It is unclear but intriuging whether these properties can be applied to reducing immune response following neural xenotransplantation of PD.
Methods
To determine whether OECs may benefit neural xenografts for PD, different compositions of grafting cells were transplanted into striatum of the PD model rats. We used apomorphine‐induced rotational behavior to evaluate effectiveness of the neural grafts on reviving DA function. Immunohistochemistry was applied to investigate the effect of OECs on the survival of neuroxenografts and underlying mechanisms of this effect.
Results
Four weeks following the xenotransplantation, we found that the PD rats receiving pfVM + OECs co‐graft exhibited a better improvement in apomorphine‐induced rotational behavior compared with those receiving only pfVM cells. This result can be explained by higher survival of DA neurons (tyrosine hydroxylase immunoreactivity) in grafted striatum of pfVM + OECs group. Furthermore, pfVM + OECs group has less immune response (CD3+ T cells and OX‐6+ microglia) around the grafted area compared with pfVM only group. These results suggest that OECs may enhance the survival of the striatal xenografts via dampening the immune response at the grafted sites.
Conclusions
Using allogeneic OECs as a co‐graft material for xenogeneic neural grafts could be a feasible therapeutic strategy to enhance results and applicability of the cell replacement therapy for PD.
Ferrate (K2FeO4) is a powerful oxidant and up to 3 mol of electrons could be captured by 1 mol of ferrate in the theoretical conversion of Fe(VI)–Fe(V)–Fe(IV)–Fe(III). However, it is reported ...that the utilization efficiency of the ferrate oxidation capacity is quite low because of the rapid autodecomposition of intermediate iron species, which negatively influences the potential of ferrate on organic pollutants control. We accidentally found that for the ferrate oxidation of carbamazepine (CBZ), bisphenol S (BPS), diclofenac (DCF), and ciprofloxacin (CIP), the determined reaction rate constants were 1.7–2.4 times lower in phosphate buffer than those in borate buffer at pH 8.0. For the reaction of ferrate with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) at pH 7.0, the determined reaction stoichiometries were 1:1.04 in 100 mM phosphate buffer, 1:1.18 in 10 mM phosphate buffer, and 1:1.93 in 10 mM borate buffer, respectively. The oxidation ability of ferrate seems depressed in phosphate buffer. A kinetic model involving the oxidation of ABTS by Fe(VI), Fe(V) and Fe(IV) species was developed and fitted the ABTS•+ formation kinetics well under different buffer conditions. The results showed that phosphate exhibited little influence on the oxidation ability of Fe(VI) and Fe(IV) species, but decreased the specific rate constants of ABTS with Fe(V) species by 1–2 orders of magnitude, resulting in the outcompeting of Fe(V) autodecomposition pathway. The complexation between phosphate anions and Fe(V) species may account for the inhibition effect of phosphate buffer. Considering that many studies regarding ferrate oxidation were carried out in phosphate buffer, the actual oxidation ability of ferrate may be underestimated.
•Inflammation, oxidative stress and mitochondrial dysfunction were closely related to IDD.•Among sirtuin family members, SIRT1, SIRT2, SIRT3 and SIRT6 were closely related to IDD.•Some sirtuin ...activating compounds exerted anti-senescence effects of IVD.
Intervertebral disc degeneration (IDD) is one of the main causes of low back pain, which seriously reduces the quality of life of patients and places a heavy economic burden on their families. Cellular senescence is considered to be an important factor leading to IDD, and inflammatory response, oxidative stress, and mitochondrial dysfunction are closely related to intervertebral disc (IVD) senescence. Therefore, inhibition of the inflammatory response and oxidative stress, along with maintaining mitochondrial function, may be useful in treating IDD. The sirtuins are a family of evolutionarily conserved nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases, which are the major molecules mediating life extension or delay of aging-related diseases. The sirtuin protein family consist of seven members (SIRT1 – 7), which are mainly involved in various aging-related diseases by regulating inflammation, oxidative stress, and mitochondrial function. Among them, SIRT1, SIRT2, SIRT3, and SIRT6 are closely related to IDD. In addition, some activators of sirtuin proteins, such as resveratrol, melatonin, magnolol, 1,4-dihydropyridine (DHP), SRT1720, and nicotinamide mononucleotide (NMN), have been evaluated in preclinical studies for their effects in preventing IDD. This review described the biological functions of sirtuins and the important roles of SIRT1, SIRT2, SIRT3, and SIRT6 in IDD by regulating oxidative stress, inflammatory response, and mitochondrial function. In addition, we introduce the status of some sirtuin activators in IDD preclinical studies. This review will provide a background for further clarification of the molecular mechanism underlying IDD and the development of potential therapeutic drugs.
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