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Fast radio bursts (FRBs) are cosmological radio transients with millisecond durations and extremely high brightness temperatures. One FRB repeater, FRB 180916.J0158+65 (FRB 180916B), was confirmed to appear 16.35-day periodic activities with 5-day activity window. Another FRB repeater, FRB 121102, and two soft gamma-ray repeaters (SGRs), SGR 1935+2154 and SGR 1806−20, also show possible periodic activities. These periodicities might originate from the precession process of young magnetars due to the anisotropic pressure from the inner magnetic fields as proposed in the literature. In this work, we analyse a self-consistent model for the rotation evolution of magnetars and obtain the evolutions of magnetar precession and obliquity. We find that if the FRB repeaters and the SGRs with (possible) periodic activities originate from the magnetar precession, their ages would be constrained to be hundreds to tens of thousands of years, which is consistent with the typical ages of magnetars. Assuming that the FRB emission is beaming in the magnetosphere as proposed in the literature, we calculate the evolution of the observable probability and the duty cycle of the active window period. We find that for a given magnetar the observable probability increases with the magnetar age in the early stage and decreases with the magnetar age in the later stage; meanwhile, there are one or two active windows in one precession period if the emission is not perfectly axisymmetric with respect to the deformation axis of a magnetar, which could be tested by the future observation for repeating FRB sources. [ABSTRACT FROM AUTHOR]

Recently, some fast radio bursts (FRBs) have been reported to exhibit complex and diverse variations in Faraday rotation measurements (RM) and polarization, suggesting that dynamically evolving magnetization environments may surround them. In this paper, we investigate the Faraday conversion (FC) effect in a binary system involving an FRB source and analyze the polarization evolution of FRBs. For a strongly magnetized high-mass companion binary, when an FRB with ∼100% linear polarization passes through the radial magnetic field of the companion star, the circular polarization (CP) component will be induced and oscillate symmetrically around the point with the degree of CP equal to zero, the rate and amplitude of the oscillation decrease as the frequency increases. The very strong plasma column density in the HMCBs can cause CP to oscillate with frequency at a very drastic rate, which may lead to depolarization. Near the superior conjunction of the binary orbit, the DM varies significantly due to the dense plasma near the companion, and the significant FC also occurs in this region. As the pulsar moves away from the superior conjunction, the CP gradually tends toward zero and then returns to its value before incidence. We also investigate the effect of the rotation of the companion star. We find that a sufficiently significant RM reversal can be produced at large magnetic inclinations and the RM variation is very diverse. Finally, we apply this model to explain some polarization observations of PSR B1744-24A and FRB 20201124A. [ABSTRACT FROM AUTHOR]

Coherent curvature radiation by charged bunches has been discussed as the radiation mechanism for radio pulsars and fast radio bursts. Important issues for this radiation mechanism include how the bunches form and disperse in the magnetosphere of a pulsar or magnetar. More likely, bunches form and disperse continuously and it remains unclear what the spectral features are for these fluctuating bunches. In this work, we consider that the bunches in a magnetosphere have a formation rate of λ B , a lifetime of τ B , and a typical Lorentz factor of γ, and analyse the spectral features of coherent curvature radiation by these fluctuating bunches. We find that the emission spectrum by a single fluctuating bunch is suppressed by a factor of ∼(λ B τ B )2 compared with that of a single persistent bunch, and there is a quasi-white noise in a wider band in the frequency domain. The high-frequency cutoff of the spectrum is at ∼max (ωpeak, 2γ2/τ B ), where ωpeak is the peak frequency of curvature radiation. If the observed spectrum is not white-noise-like, the condition of 2γ2λ B ≳ min (ωpeak, 2γ2/τ B ) would be required. Besides, the radiation by multiple fluctuating bunches along a field line is the incoherent summation of the radiation by single bunches if the bunch separation is longer than the wavelength. Conversely, a coherent summation should be involved. We also discuss the effects of bunch structures and the mechanism of bunch formation and dispersion. [ABSTRACT FROM AUTHOR]

Recently, some fast radio burst (FRB) repeaters were reported to exhibit complex, diverse variations of Faraday rotation measures (RMs), which implies that they are surrounded by an inhomogeneous, dynamically evolving, magnetized environment. We systematically investigate some possible astrophysical processes that may cause RM variations of an FRB repeater. The processes include (1) a supernova remnant (SNR) with a fluctuating medium; (2) a binary system with stellar winds from a massive/giant star companion or stellar flares from a low-mass star companion; (3) a pair plasma medium from a neutron star (including pulsar winds, pulsar wind nebulae, and magnetar flares); (4) outflows from a massive black hole. For the SNR scenario, a large relative RM variation within a few years requires that the SNR is young with a thin and local anisotropic shell, or the size of dense gas clouds in interstellar/circumstellar medium around the SNR is extremely small. If the RM variation is caused by the companion medium in a binary system, it is more likely from the stellar winds of a massive/giant star companion. The RM variation contributed by stellar flares from a low-mass star is disfavored, because this scenario predicts an extremely large relative RM variation during a short period of time. The scenarios invoking a pair plasma from a neutron star can be ruled out due to their extremely low RM contributions. Outflows from a massive black hole could provide a large RM variation if the FRB source is in the vicinity of the black hole. [ABSTRACT FROM AUTHOR]

Initial efforts to mitigate the COVID-19 pandemic have relied heavily on non-pharmaceutical interventions (NPIs), including physical distancing, hand hygiene, and mask-wearing. However, an effective vaccine is essential to containing the spread of the virus. We developed a compartmental model to examine different vaccine strategies for controlling the spread of COVID-19. Our framework accounts for testing rates, test-turnaround times, and vaccination waning immunity. Using reported case data from the city of Toronto, Canada between Mar-Dec, 2020 we defined epidemic phases of infection using contact rates as well as the probability of transmission upon contact. We investigated the impact of vaccine distribution by comparing different permutations of waning immunity, vaccine coverage and efficacy throughout various stages of NPI's relaxation in terms of cases and deaths. The basic reproduction number is also studied. We observed that widespread vaccine coverage substantially reduced the number of cases and deaths. Under phases with high transmission, an early or late reopening will result in new resurgence of the infection, even with the highest coverage. On the other hand, under phases with lower transmission, 60% of coverage is enough to prevent new infections. Our analysis of R0 showed that the basic reproduction number is reduced by decreasing the tests turnaround time and transmission in the household. While we found that household transmission can decrease following the introduction of a vaccine, public health efforts to reduce test turnaround times remain important for virus containment. [ABSTRACT FROM AUTHOR]

Background: Although neoadjuvant anti-PD-1 immunotherapies have shown good efficacy in non-small cell lung cancer (NSCLC) patients, there is still a lack of effective predictive markers. We aimed to develop a pretreatment histologic scoring system to predict the efficacy of neoadjuvant immunotherapy.Methods: One hundred forty NSCLC cases were evaluated in this study. Initially, surgical specimens from 31 squamous cell lung cancer patients treated with neoadjuvant anti-PD-1 therapy and their eligible paired pretreatment biopsies were used for pathologic evaluation and developing the pretreatment scoring system, immune-related histologic phenotype assessment criteria (irHPC). Three trained pathologists independently scored the haematoxylin-eosin (HE) slides of the pretreatment tumour biopsies according to irHPC. The follow-up was from 07 March 2018 to 31 December 2021, mainly focusing on disease-free survival (DFS) and overall survival (OS). Second, 109 biopsies of lung squamous cell carcinoma were evaluated to explore the relationship between eosinophils and PD-L1 expression.Results: Superior 2-year DFS rates and 2-year OS rates were observed in patients who achieved major pathologic response (MPR) (MPR vs. non-MPR: 92.9% vs. 78.6%; 100.0% vs. 93.3%). Whether necrosis was included in the calculation of the per cent of residual viable tumour (%RVT) or not had almost no effect on the consistency of pathologic assessment and the histological response grouping. The interpathologist variability in assessing %RVT with immune-activated phenotype was not statistically significant (P = 0.480). Four immune-related features of pretreatment biopsies were included for calculating the predictive score. The trained pathologist accurately predicted most cases according to irHPC. For interobserver reproducibility using "2 points" as the cutoff, the overall per cent agreement was 77.8%. The reliability between pathologists for a binary tumour evaluation showed "moderate" agreement (κ = 0.54). Patients with scores ≥ 2 points tended to have better 2-year DFS rates and 2-year OS rates than those with scores < 2 points (85.7% vs. 71.4%; 100.0% vs. 87.5%).Conclusions: The irHPC scoring system reflecting the preexisting immune response could be used to predict pathologic response to neoadjuvant immunotherapy, possibly further predicting the long-term prognosis, but larger trials are needed for verification. [ABSTRACT FROM AUTHOR]

Background: Countries that aimed for eliminating the cases of COVID-19 with test-trace-isolate policy are found to have lower infections, deaths, and better economic performance, compared with those that opted for other mitigation strategies. However, the continuous evolution of new strains has raised the question of whether COVID-19 eradication is still possible given the limited public health response capacity and fatigue of the epidemic. We aim to investigate the mechanism of the Zero-COVID policy on outbreak containment, and to explore the possibility of eradication of Omicron transmission using the citywide test-trace-isolate (CTTI) strategy. Methods: We develop a compartmental model incorporating the CTTI Zero-COVID policy to understand how it contributes to the SARS-CoV-2 elimination. We employ our model to mimic the Delta outbreak in Fujian Province, China, from September 10 to October 9, 2021, and the Omicron outbreak in Jilin Province, China for the period from March 1 to April 1, 2022. Projections and sensitivity analyses were conducted using dynamical system and Latin Hypercube Sampling/ Partial Rank Correlation Coefficient (PRCC). Results: Calibration results of the model estimate the Fujian Delta outbreak can end in 30 (95% confidence interval CI: 28–33) days, after 10 (95% CI: 9–11) rounds of citywide testing. The emerging Jilin Omicron outbreak may achieve zero COVID cases in 50 (95% CI: 41–57) days if supported with sufficient public health resources and population compliance, which shows the effectiveness of the CTTI Zero-COVID policy. Conclusions: The CTTI policy shows the capacity for the eradication of the Delta outbreaks and also the Omicron outbreaks. Nonetheless, the implementation of radical CTTI is challenging, which requires routine monitoring for early detection, adequate testing capacity, efficient contact tracing, and high isolation compliance, which constrain its benefits in regions with limited resources. Moreover, these challenges become even more acute in the face of more contagious variants with a high proportion of asymptomatic cases. Hence, in regions where CTTI is not possible, personal protection, public health control measures, and vaccination are indispensable for mitigating and exiting the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

A fiber Bragg grating (FBG) interrogator is a scientific instrument that converts the wavelength change of FBG sensors into readable electrical signals. To achieve miniaturization and integration of FBG interrogator, we designed and fabricated a 36-channel array waveguide grating (AWG) on silica-based planar lightwave circuits (PLC) as a key device in a built FBG interrogation system. It is used to achieve continuous demodulation in C-band, while maintaining high resolution. This AWG has a 1.6 nm channel spacing, 3-dB bandwidth of 1.76 nm, non-adjacent channel crosstalk of −29.76 dB, and insertion loss of 3.46 dB. The dynamic range of the FBG interrogation system we built was tested to be 1522.4–1578.4 nm, with an interrogation resolution of 1 pm and accuracy of less than 1 pm in the dynamic range of 1523.16–1523.2 nm. The test results show that the FBG interrogation technology, based on AWG, can realize FBG wavelengths accurately demodulated, which has high application value in aerospace, deep sea exploration, and environmental monitoring, as well as other fields. [ABSTRACT FROM AUTHOR]

Background: Since December 2020, public health agencies have implemented a variety of vaccination strategies to curb the spread of SARS-CoV-2, along with pre-existing Nonpharmaceutical Interventions (NPIs). Initial strategies focused on vaccinating the elderly to prevent hospitalizations and deaths, but with vaccines becoming available to the broader population, it became important to determine the optimal strategy to enable the safe lifting of NPIs while avoiding virus resurgence.Methods: We extended the classic deterministic SIR compartmental disease-transmission model to simulate the lifting of NPIs under different vaccine rollout scenarios. Using case and vaccination data from Toronto, Canada between December 28, 2020, and May 19, 2021, we estimated transmission throughout past stages of NPI escalation/relaxation to compare the impact of lifting NPIs on different dates on cases, hospitalizations, and deaths, given varying degrees of vaccine coverages by 20-year age groups, accounting for waning immunity.Results: We found that, once coverage among the elderly is high enough (80% with at least one dose), the main age groups to target are 20-39 and 40-59 years, wherein first-dose coverage of at least 70% by mid-June 2021 is needed to minimize the possibility of resurgence if NPIs are to be lifted in the summer. While a resurgence was observed for every scenario of NPI lifting, we also found that under an optimistic vaccination coverage (70% coverage by mid-June, along with postponing reopening from August 2021 to September 2021) can reduce case counts and severe outcomes by roughly 57% by December 31, 2021.Conclusions: Our results suggest that focusing the vaccination strategy on the working-age population can curb the spread of SARS-CoV-2. However, even with high vaccination coverage in adults, increasing contacts and easing protective personal behaviours is not advisable since a resurgence is expected to occur, especially with an earlier reopening. [ABSTRACT FROM AUTHOR]

Background: Globally, nonpharmaceutical interventions for COVID-19, including stay-at-home policies, limitations on gatherings and closure of public spaces, are being lifted. We explored the effect of lifting a stay-at-home policy on virus resurgence under different conditions. Methods: Using confirmed case data from Toronto, Canada, between Feb. 24 and June 24, 2020, we ran a compartmental model with household structure to simulate the impact of the stay-at-home policy considering different levels of compliance. We estimated threshold values for the maximum number of contacts, probability of transmission and testing rates required for the safe reopening of the community. Results: After the implementation of the stay-at-home policy, the contact rate outside the household fell by 39% (from 11.58 daily contacts to 7.11). The effective reproductive number decreased from 3.56 (95% confidence interval [CI] 3.02–4.14) on Mar. 12 to 0.84 (95% CI 0.79–0.89) on May 6. Strong adherence to stay-at-home policies appeared to prevent SARS-CoV-2 resurgence, but extending the duration of stay-at-home policies beyond 2 months had little added effect on cumulative cases (25 958 for 65 days of a stay-at-home policy and 23 461 for 95 days, by July 2, 2020) and deaths (1404 for 65 days and 1353 for 95 days). To avoid a resurgence, the average number of contacts per person per day should be kept below 9, with strict nonpharmaceutical interventions in place. Interpretation: Our study demonstrates that the stay-at-home policy implemented in Toronto in March 2020 had a substantial impact on mitigating the spread of SARS-CoV-2. In the context of the early pandemic, before the emergence of variants of concern, reopening schools and workplaces was possible only with other nonpharmaceutical interventions in place. [ABSTRACT FROM AUTHOR]

Background: Percutaneous endoscopic lumbar discectomy (PELD) is a relatively safe and effective minimally invasive surgery in the treatment of calcified lumbar disc herniation (CLDH). However, studies on percutaneous endoscopic interlaminar discectomy (PEID) and percutaneous endoscopic transforaminal discectomy (PETD) for CLDH have rarely been reported. This research aimed to compare the clinical efficacy of PEID and PETD for L5-S1 CLDH.Methods: We retrospectively analyzed 54 consecutive patients with L5-S1 CLDH treated with PELD at our institution from August 2016 to August 2020. Patients were divided into PEID group (n = 28) and PETD (n = 26) group according to the surgical methods. The demographic characteristics and surgical results of the two groups were compared. Clinical outcomes were estimated by the visual analog scale (VAS) for leg pain, Oswestry disability index (ODI) and modified MacNab criteria.Results: All patients were successfully operated on by PEID or PETD. No significant differences in the demographic characteristics, intraoperative blood loss, postoperative hospital stay and complication rate were noted between the PEID and PETD groups. The excellent and good rates in the PEID group were similar to those in the PETD group (89.29% vs 88.46%, P = 1.000), whereas the PEID group exhibited superior results for operative time (min) (64.61 ± 5.60 vs 85.58 ± 8.52, P < 0.001) and fluoroscopy times (n) (2.93 ± 0.90 vs 13.35 ± 2.30, P < 0.001) compared with the PETD group.Conclusions: PEID has achieved good clinical efficacy as PETD for L5-S1 CLDH. Compared with PETD, PEID has the advantages of shorter operative time and a reduced number of fluoroscopy times in the treatment of CLDH. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a chronic and progressive process. It is the most important pathological basis of cardiovascular disease and stroke. Vascular smooth muscle cells (VSMCs) are an essential cell type in atherosclerosis. Previous studies have revealed that VSMCs undergo phenotypic transformation in atherosclerosis to participate in the retention of atherogenic lipoproteins as well as the formation of the fibrous cap and the underlying necrotic core in plaques. The emergence of lineage-tracing studies indicates that the function and number of VSMCs in plaques have been greatly underestimated. In addition, recent studies have revealed that VSMCs make up at least 50% of the foam cell population in human and mouse atherosclerotic lesions. Therefore, understanding the formation of lipid-loaded VSMCs and their regulatory mechanisms is critical to elucidate the pathogenesis of atherosclerosis and to explore potential therapeutic targets. Moreover, combination of many complementary technologies such as lineage tracing, single-cell RNA sequencing (scRNA-seq), flow cytometry, and mass cytometry (CyTOF) with immunostaining has been performed to further understand the complex VSMC function. Correct identification of detrimental and beneficial processes may reveal successful therapeutic treatments targeting VSMCs and their derivatives during atherosclerosis. The purpose of this review is to summarize the process of lipid-loaded VSMC formation in atherosclerosis and to describe novel insight into VSMCs gained by using multiple advanced methods. [ABSTRACT FROM AUTHOR]

The recent discovery of a Galactic fast radio burst (FRB) occurring simultaneously with an X-ray burst (XRB) from the Galactic magnetar SGR J1935+2154 implies that at least some FRBs arise from magnetar activities. We propose that FRBs are triggered by crust fracturing of magnetars, with the burst event rate depending on the magnetic field strength in the crust. Since the crust-fracturing rate is relatively higher in polar regions, FRBs are more likely to be triggered near the directions of multipolar magnetic poles. Crust fracturing produces Alfvén waves, forming a charge-starved region in the magnetosphere and leading to nonstationary pair plasma discharges. An FRB is produced by coherent plasma radiation due to nonuniform pair production across magnetic field lines. Meanwhile, the FRB-associated XRB is produced by the rapid relaxation of the external magnetic field lines. In this picture, the sharp-peak hard X-ray component in association with FRB 200428 is from a region between adjacent trapped fireballs, and its spectrum with a high cutoff energy is attributed to resonant Compton scattering. The persistent X-ray emission is from a hot spot heated by the magnetospheric activities, and its temperature evolution is dominated by magnetar surface cooling. Within this picture, magnetars with stronger fields tend to produce brighter and more frequent repeated bursts. [ABSTRACT FROM AUTHOR]

Background: Modular prosthesis fracture, especially distal femoral fracture, is a rare complication of total hip arthroplasty (THA). However, it is catastrophic, and may have a serious impact on the patients. A distal femoral prosthesis fracture in a patient with developmental dysplasia of the hip (DDH) with nonunion at the subtrochanteric osteotomy site has not yet been reported in any literature. This report presents the first such case, with a purpose of analyzing the causes of modular prosthesis fractures and nonunion of the osteotomy area, so as to provide orthopedic surgeons with experience and lessons.Case Presentation: We report the case of a 52-year-old woman with the distal femoral prosthesis fracture after THA and subtrochanteric osteotomy for Crowe type IV DDH. The patient had severe pain in the left thigh and her activities were limited. Plain radiographs revealed fracture of the left distal femoral prosthesis and nonunion in the subtrochanteric osteotomy region of the left femur. After a revision of the THA, the patient's symptoms were resolved.Conclusions: A prosthesis fracture combined with nonunion at the subtrochanteric osteotomy site is a rare complication. Modular THA combined with a subtrochanteric osteotomy in the treatment of Crowe type IV DDH should reduce the damage to blood supply and avoid further nonunion of the osteotomy area, which may otherwise lead to modular prosthesis fractures. A detailed preoperative plan and suitable rehabilitation program may help minimize the occurrence of subtrochanteric osteotomy nonunion and reduce complications, including femoral prosthesis fractures, in patients with DDH. [ABSTRACT FROM AUTHOR]

Homogeneously Eu3+ doped LaOCl single crystals are firstly synthesized in a molten KCl-LiCl flux, and the well-shaped LaOCl:Eu3+ polyhedral micro-plates exhibit noticeable luminescent properties. The bulk LaOCl:Eu3+ micro-plate with a width of 1.03 μm and 1.37 μm in length shows a single crystal characteristic with the crystal face orientation of [00 1 ‾ ]. Both XRD patterns and EDS mapping indicate that the Eu3+ ions have been homogeneously doped into LaOCl lattice. LaOCl:Eu3+ nucleuses generated in molten KCl-LiCl flux at even 350 °C benefited to the decomposition of La(OH) 3 :Eu3+ precursor, and polyhedral LaOCl micro-plate is easily formed in molten KCl-LiCl salt due to the solid-ionic reaction and crystal growth. The luminescent properties of LaOCl:Eu3+ are firstly enhanced and then weakened with the increasing concentration of the doped Eu3+, 6% Eu3+ doped LaOCl:Eu3+ exhibits the best luminescent properties which can be used as a potential LED material. [ABSTRACT FROM AUTHOR]

A series of NiMo/FDU-12 catalysts with tunable pore diameters and mesostructures have been controllably synthesized by adjusting the synthetic hydrothermal temperature and applied for the hydrodesulfurization of dibenzothiophene and its derivative. The state-of-the-art electron tomography revealed that the pore sizes of FDU-12 supports were enlarged with the increase in the hydrothermal temperature and the mesostructures were transformed from ordered cage-type pores to locally disordered channels. Meanwhile, the MoS2 morphology altered from small straight bar to semibending arc to spherical shape and finally to larger straight bar with the change of support structures. Among them, FDU-12 hydrothermally treated at 150 °C possessed appropriate pore diameter and connected pore structure and was favorable for the formation of highly active MoS2 with curved morphology; thus, its corresponding catalyst exhibited the best HDS activity. Furthermore, it was indicated that the isomerization pathway could be significantly improved for HDS of 4,6-dimethyldibenzothiophene after the addition of aluminum, which was expected to be applied to the removal of the macromolecular sulfur compounds. Our study sheds lights on the relationship between support effect, active sites morphology and HDS performance, and also provides a guidance for the development of highly active HDS catalysts. [ABSTRACT FROM AUTHOR]

In this paper, we explore the viewing angle effect on black hole–neutron star (BH–NS) merger kilonova lightcurves. We extrapolate the fitting formulae for the mass and velocity of dynamical ejecta across a wide mass ratio range validated with 66 simulations and use them in kilonova lightcurve calculations. The calculated peak luminosity of a BH–NS merger kilonova is typically about a few times 1041 erg s−1, which is always ≲4.5 × 1041 erg s−1. This corresponds to AB absolute magnitudes fainter than ∼−15 mag in the optical and ∼−16 mag in the infrared. The dynamical ejecta usually contribute to the majority of the kilonova emission, as its projected photosphere area is much larger than that of the disk wind outflows. The fitted blackbody temperature and the observed multiband lightcurve shape are insensitive to the line of sight. The peak time of the observed multiband lightcurves, affected by the light-propagation effect, is related to the relative motion direction between the dynamical ejecta and the observer. The predicted peak luminosity, which changes with the projected photosphere area, only varies by a factor of ∼(2–3) (or by ∼1 mag) for different viewing angles. When taking the short-duration gamma-ray burst afterglow into account, for an on-axis geometry, the kilonova emission is usually outshone by the afterglow emission and can only be observed in the redder bands, especially in the K band at late times. Compared with GW 170817/AT 2017gfo, BH–NS merger kilonovae are optically dim but possibly infrared bright, and have lower fitting temperature at the same epoch after the merger. [ABSTRACT FROM AUTHOR]

The first repeating fast radio burst (FRB), FRB 121102, was found to be associated with a spatially coincident, persistent nonthermal radio source, but the origin of the persistent emission remains unknown. In this paper, we propose that the persistent emission is produced via a synchrotron-heating process by multiple bursts of FRB 121102 in a self-absorbed synchrotron nebula. With a population of bursts of the repeating FRB absorbed by the synchrotron nebula, the energy distribution of electrons in the nebula will change significantly. As a result, the spectrum of the nebula will show a hump steadily. For the persistent emission of FRB 121102, the total energy of bursts injecting into the nebula is required to be about 3.3 × 1049 erg, the burst injection age is over 6.7 × 104 yr, the nebula size is ∼0.02 pc, and the electron number is about 3.2 × 1055. We predict that as more bursts inject, the brightness of the nebula would be brighter than the current observation, and meanwhile, the peak frequency would become higher. Due to the synchrotron absorption of the nebula, some low-frequency bursts would be absorbed, which may explain why most bursts were detected above ∼1 GHz. [ABSTRACT FROM AUTHOR]

The physical origin of fast radio bursts (FRBs) is still unknown. Multiwavelength and polarization observations of an FRB source would be helpful to diagnose its progenitor and environment. So far only the first repeating source FRB 121102 appears to be spatially coincident with a persistent radio emission. Its bursts also have very large values of the Faraday rotation measure (RM), i.e.,. We show that theoretically there should be a simple relation between RM and the luminosity of the persistent source of an FRB source if the observed RM mostly arises from the persistent emission region. FRB 121102 follows this relation given that the magnetic field in the persistent emission region is highly ordered and that the number of relativistic electrons powering the persistent emission is comparable to that of nonrelativistic electrons that contribute to RM. The nondetections of persistent emission sources from all other localized FRB sources are consistent with their relatively small RMs () according to this relation. Based on this picture, the majority of FRBs without a large RM are not supposed to be associated with bright persistent sources. [ABSTRACT FROM AUTHOR]

Cognitive diagnostic computerized adaptive testing (CD-CAT) has been suggested by researchers as a diagnostic tool for assessment and evaluation. Although model-based CD-CAT is relatively well researched in the context of large-scale assessment systems, this type of system has not received the same degree of research and development in small-scale settings, such as at the course-based level, where this system would be the most useful. The main obstacle is that the statistical estimation techniques that are successfully applied within the context of a large-scale assessment require large samples to guarantee reliable calibration of the item parameters and an accurate estimation of the examinees' proficiency class membership. Such samples are simply not obtainable in course-based settings. Therefore, the nonparametric item selection (NPS) method that does not require any parameter calibration, and thus, can be used in small educational programs is proposed in the study. The proposed nonparametric CD-CAT uses the nonparametric classification (NPC) method to estimate an examinee's attribute profile and based on the examinee's item responses, the item that can best discriminate the estimated attribute profile and the other attribute profiles is then selected. The simulation results show that the NPS method outperformed the compared parametric CD-CAT algorithms and the differences were substantial when the calibration samples were small. [ABSTRACT FROM AUTHOR]

Monodispersed dendritic mesoporous silica/carbon nanospheres (DMS/CNs) with adjustable particle sizes and carbon contents have been controllably fabricated via a facile oil-water biphase stratification approach combined with an in situ carbonization of surfactant template strategy. The obtained materials were utilized as adsorbents for the adsorptive desulfurization of dibenzothiophene, and the results showed that the adsorbent with the smaller particle size and larger pore size had a faster adsorption equilibrium and DMS/CNs with the higher carbon contents exhibited better sulfur adsorption capacity. This might be because the carbon substrate deposited on the mesoporous channels could alter the textural and chemical properties of materials and thus could improve the adsorptive performance. Moreover, DMS/CNs with the unique center-radial pore structure and large surface area were favorable for the incorporation of active metals, and the adsorptive capacity and selectivity could be greatly enhanced after the incorporation of AgNO3. The superior adsorptive performance might result from a good combination of its unique pore channels and a synergistic effect between carbon substrate and silver species. [ABSTRACT FROM AUTHOR]

Abstract Herein, a novel electrochemical ultrasensitive immunosensor was designed for detecting prostate-specific antigen (PSA) with three-dimensional (3D) PtCu hollow nanoframes (PtCu HNFs) as signal amplification. The highly opened PtCu HNFs were synthesized by a one-pot solvothermal method with cetyltrimethylammonium chloride (CTAC) and trishydroxymethyl aminomethane (Tris) as co-structuring directors. The architectures enlarged the loading of prostate specific antibodies (Ab) and efficiently catalyzed hydrogen peroxide (H 2 O 2) reaction, ultimately amplifying the signals. And polylysine was used to disperse PtCu HNFs, improve the biocompatibility and bind the Ab on the electrode surface. The fabricated immunosensor exhibited lower detection limit (0.003 ng mL–1, S / N = 3), and wider linear range (0.01–100.0 ng mL–1), along with the improved reproducibility, selectivity and stability for the assay of PSA. Thus, it is a desirable platform for PSA detection in clinical diagnosis and practical applications. Highlights • Uniform PtCu HNFs were synthesized by a simple solvothermal method. • Tris and CTAC acted as the co-structure-directing agents. • Polylysine can well disperse PtCu HNFs with increased biocompatibility. • PtCu HNFs was constructed for PSA immunosensor with excellent analytic performance. [ABSTRACT FROM AUTHOR]

In this paper, we consider the design of statistical multiple-input-multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) beamformers for millimeter wave (mmWave) channels. The transmitter designs the subcarrier beamformers based on the statistics of the channel, without instantaneous channel information. To overcome the radio frequency (RF) limitation in mmWave application, the subcarrier beamformers are implemented in a hybrid structure, which imposes constraints on the design of subcarrier beamformers. We analyze the unconstrained statistical subcarrier beamformers using spectral analysis of the subcarrier channels. The analysis shows that, for each subcarrier channel, the optimal statistical beamformer is approximately a linear combination of optimal statistical beamformers for some appropriately defined narrowband single-cluster subchannels. The result suggests a design of the subcarrier beamformers that can be readily implemented in a hybrid structure. Furthermore, a hybrid design for the receiver is proposed based on the concept of vector quantization. Simulations are given to show that the use of a hybrid beamforming structure incurs a minor degradation in transmission rate. With three RF chains, the performance is close to that of all digital statistical beamforming. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the correlations between metabolic parameters (MPs) of 18F‐fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT), serum tumor markers (STMs), and tumor mutational burden (TMB) in patients with non‐small cell lung cancer (NSCLC). Materials and Methods: In this retrospective study, we enrolled 129 patients with NSCLC (males, 78; females, 51) who underwent baseline TMB and STM tests and 18F‐FDG PET/CT scans before treatment between March 2018 and September 2022. Patients were categorized into TMB‐high (TMB ≥10 mutations/Mb; n = 27 [20.9%]) and non‐TMB‐high (TMB <10 mutations/Mb; n = 102 [79.1%]) groups. Binary logistic regression analyses were performed to determine independent predictors of TMB‐high. Univariate and multivariate linear regression analyses were performed to determine independent predictors of TMB level on a log scale. Subgroup analyses for adenocarcinoma (ADC), ADC with EGFR+, ADC with EGFR−, and squamous cell carcinoma (SCC) were performed. Results: For ADC, all MPs (SULpeak, SULmax, SULmean, MTV, and TLG) were significantly higher in the TMB‐high group than the non‐TMB‐high group; smoker (odds ratio [OR] = 27.08, p = 0.018), EGFR+ (OR = 0.03, p = 0.033), KRAS+ (OR = 7.98, p = 0.083), high CEA (OR = 33.56, p = 0.029), and high CA125 (OR = 13.68, p = 0.030) were independent predictors of TMB‐high; and all MPs showed significant positive linear correlations with TMB on a log scale, with SULpeak as an independent predictor. However, no significant correlation was observed for SCC. Conclusion: MPs and STMs can predict the TMB level for patients with ADC, and may serve as potential substitutes for TMB with increased value and easy implementation in guiding immunotherapy through noninvasive methods. [ABSTRACT FROM AUTHOR]

Nanoceria was synthesized by treating cerium carbonate hydrate in a molten KOH-NaOH mixture at 200 °C. The nanoceria thus synthesized under a hydrogen atmosphere had a crystal size of 21.6 nm measured by XRD, consistent with the particle size of 23 nm measured by TEM. Raman spectra results indicated that the nanoceria produced under hydrogen had a downshift of 0.9 cm −1 from the sample synthesized in air. XPS spectra showed that the Ce 3+ fraction of the nanoceria synthesized in hydrogen was greater than that produced in air. The oxygen vacancies were formed by partial oxidization of the precursor in molten KOH-NaOH mixture. The UV–visible absorption properties of ceria synthesized under hydrogen showed a 34 nm red-shift compared with that synthesized in air. The nanoceria prepared in this work had a better catalytic property for CO oxidization than the commercial nanoceria. Results indicated that the increased Ce 3+ fraction or oxygen vacancies formed by this partial oxidization process extended the absorption edge of ceria resulting in a narrower band gap, and enhanced the catalytic activity of nanoceria. This method has proven to provide a simple and scalable method for the synthesis of high quality nanoceria. [ABSTRACT FROM AUTHOR]

The present study aimed to clarify the association between kinesin family member 11 (KIF11) and human breast cancer, and the effect of KIF11 on breast cancer cell progression. Western blot analysis, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis, retroviral infection, immunohistochemistry staining, MTT assay, anchorage‑independent growth ability assay and tumorigenicity assay were all used in the present study. Western blot and RT‑qPCR analysis revealed that the expression of KIF11 was markedly increased in malignant cells compared with that in non‑tumorous cells at the mRNA and protein level. Immunohistochemical analysis revealed that KIF11 expression was upregulated in 256/268 (95.8%) paraffin‑embedded archival breast cancer biopsies. Statistical analysis demonstrated a significant association between the upregulation of KIF11 expression and the progression of breast cancer. Multivariate analysis revealed that KIF11 upregulation represents an independent prognostic indicator for the survival of patients with breast cancer. Tumorigenicity experiments were further used to evaluate the effect of KIF11 in non‑obese diabetic/severe combined immunodeficient mice. Silencing endogenous KIF11 by short hairpin RNAs inhibited the proliferation of breast cancer cells in vitro and in vivo. The present results suggest that KIF11 may serve an important function in the proliferation of breast cancer and may represent a novel and useful prognostic marker for breast cancer. [ABSTRACT FROM AUTHOR]

For the efficient surface plasmon resonance (SPR)-based DNA assay researching, signal amplification tactics were absolutely necessary. In this work, a sensitive SPR-DNA sensor was developed by employing in situ synthesis of copper nanoparticles (CuNPs) templated by poly-T sequences DNA from terminal deoxynucleotidyl transferase (TdT)-mediated extension, and synergistically with nano-effect deposition as the mass relay. The objective of this strategy was manifold: firstly, t DNA hybridized with the optimal designed probes to active the TdT-mediated DNA extension onto the surface of SPR chip, resulted a long poly-T sequences ssDNA chain in ds DNA terminal onto surface of gold chip and characterized by SPR signal amplitudes. Secondly, copper ion (Cu 2+ ) adsorbed into the skeleton of poly-T sequences DNA, with the aid of ascorbic acid (VC) to achieve the Cu 2+ reduction, copper nanostructures (CuNPs) was synchronously generated onto the single nucleotide chain anchoring in ds DNA derivatives and the formation was featured by transmission electron micrographs (TEM) and electrochemistry. Lastly, ds DNA-complexed CuNPs (CuNPs@ ds DNA) triggered the final signal amplification via real-time conversion of the additive catechol violet (CV) into oligomer or chelation precipitation by CuNPs-tagged reporters. With the proposed setups, a precise and replicable DNA sensing platform for specific target oligo was obtained with a detection limit down to 3.21 femtomolar, demonstrating a beneficial overlapping exploitation of nanomaterials and biochemical reaction as unique SPR infrastructure. Such triple-amplification strategic setups, the possibility of various methods abutment and biocompatibility weight reactor was amassed and adapted to more biological detection field. [ABSTRACT FROM AUTHOR]

For a time-correlated channel, we consider the differential feedback of the geometrical mean decomposition (GMD) precoder, which is known to be optimal for a number of criteria. When the channel varies slowly, we can expect the optimal GMD precoders of consecutive channel uses to be close. We consider the feedback of the so-called differential precoder and show that it lies in a neighborhood of the identity matrix using matrix perturbation theory. Furthermore, the radius of the neighborhood is shown to be proportional to a time-correlation parameter. Such a characterization allows for subsequent efficient quantization of the differential precoder. We show how to design codewords for the prescribed radius by perturbing the identity matrix and applying QR decomposition on the perturbed matrix. Simulations are given to demonstrate that, with a small feedback rate, the performance of the proposed differential GMD comes close to the case when perfect channel state information is available to the transmitter for slowly time-varying channels like those in indoor and microcellular environments. [ABSTRACT FROM PUBLISHER]

This paper presents a novel brushless doubly-fed pulsed alternator (BDPA) in the direct-drive power supply system for high-energy pulsed lasers. There are two sets of stator winding which are embedded in the stator slots of BDPA. One is called power winding and another is called control winding. The rotor winding is short circuit. Because there is no brush, compared with the compensated pulsed alternator, BDPA has higher reliability and can run at higher speeds to get higher energy-storing density. Besides, when the system works on the state of continuous multiple pulses, with a decrease of speed, the BDPA can maintain the frequency and voltage of the power winding constant basically. In this paper, the design procedure of BDPA is proposed according to the requirement of the high-energy pulsed lasers. Utilizing the finite-element model of the alternator, we can analyze the electromagnetic properties and calculate inductance parameters of the BDPA to verify the design scheme. Meanwhile, the simulation model of the direct-drive power supply system is established in MATLAB/Simulink to analyze the output performance of the flashlamp load. The simulation results confirmed the feasibility of design scheme of BDPA for the system. [ABSTRACT FROM PUBLISHER]

[Display omitted] • MOFs-derived Ni-Co alloy catalysts were used in NCH selective hydrogenation. • Ni-Co alloy effects facilitate CoO x reduction and increase the Co0 amounts. • Ethylenediamine favors the N -CHH formation and reduces the whole energy barriers. • Pyridinic-N favors intermediate N -CHH conversion to CHO. • Ni 1 Co 2 (1 1 1) crystal surface presents the lowest energy barrier of the α-H transfer. High-efficiency Ni-Co alloy encapsulated in N -doped carbon layer (Ni 1 Co 2 @NC-APTES) catalysts were prepared via simple Ni-Co-MOF pyrolyzation and applied in the selective hydrogenation of nitrocyclohexane (NCH) to cyclohexanone oxime (CHO). The results show that the alloy effects between Ni and Co can highly promote catalytic activity. The appropriate Ni addition can facilitate the reduction of CoO x and increase zero-valent Co (Co0) amounts. Moreover, pyridinic-N doping increases the Lewis basicity, which favors the intermediate cyclohexylhydroxylamine (N -CHH) conversion to CHO. Additionally, the in-situ DRIFT and density functional theory (DFT) calculations propose the mechanism for NCH hydrogenation in ethylenediamine (EDA) and the results show that the EDA changes the reaction path of NCH hydrogenation to CHO, prefers to form N -CHH, and significantly reduces the whole reaction energy barrier of NCH to CHO. Moreover, the Ni 1 Co 2 (1 1 1) crystal surface with the lowest d -band center and the strongest Ni-Co alloy effects presents the highest adsorption energies of H 2 and NCH, the lowest adsorption energies of H* and CHO, and the lowest energy barrier of the α -H transfer which is conducive to form the N -CHH. Under the optimum conditions, the Ni 1 Co 2 @NC-APTES gives 93.6% selectivity to CHO at 94.5% NCH conversion in EDA. [ABSTRACT FROM AUTHOR]

Reliable connections are crucial for a bridge anti-collision protective system. Thus, this study proposes an innovative butterfly-like connection to tightly connect all segments of the pier composite protective system. The composite protective system is composed of four large segments, made of glass fiber-reinforced polymer (GFRP) panels, GFRP lattice plates, GFRP octagonal honeycomb tubes, round steel tubes, and polyurethane (PU) foam cores. The segments are jointed as a whole protective system by using eight proposed butterfly-like connections. First, the quasi-static tensile test is carried out to study the tensile strength and failure mechanism of the proposed connection. Then, a numerical model of the connection is established to determine the optimization parameter, and the numerical results are verified by experimental data. The optimal structural parameters for the connection are determined by parameter analysis using numerical results. Finally, a case study of a cable-supported bridge under vessel collision is numerically analyzed to comprehensively evaluate the overall protective performance and the dynamic reliability of the connection. It was found that the dynamic performance of the proposed connection is so reliable that it can ensure the protection system's excellent performance. Also, the composite protective system can effectively reduce the collision force and the damage to both bridge and vessel. [ABSTRACT FROM AUTHOR]

Nanoceria is an important function material and is widely used in catalytic applications due to its excellent redox properties. Here, we report a simple method to synthesize uniform polyhedral nanoceria powder by the KCl-LiCl molten salt method. TEM micrographs of the product showed that polyhedral nanoceria particles of 30 nm average size were obtained from cerium carbonate hydroxide when treated at 600°C for 4 hours. Results indicated that the crystal structure broke down to ceria crystal nuclei in the molten salt system at an elevated temperature, and the Ce3+ dissolved in the KCl-LiCl molten salts provided a cerium source for crystal growth. The crystal and particle sizes increased with treatment temperature. UV-visible absorption results showed that this nanoceria powder had a significant red shift, and its narrow band gap of 2.7 eV suggests a potential application for photocatalysis. The produced nanoceria had a somewhat lower catalytic activity for CO oxidization than commercial nanoceria, mainly due to smaller specific surface area, but had a higher stability. [ABSTRACT FROM AUTHOR]

Hybrid precoding that combines analog RF processing and digital baseband processing has been shown to be a promising technique for transceivers with limited number of RF chains. The RF processing, due to power and complexity issue, is typically done by using phase shifters. A recent study shows that hybrid precoding is no loss of generality if each coefficient of the analog precoder is implemented by using two phase shifters. In this paper, we consider two possible implementation structures that use Two pHase shIfters for each Coefficient (THIC). These two structures, having the same performance when the phases can take on continuum values, behave differently upon quantization, as the analysis shows. For a small number of quantization bits, the precoder implemented using THIC is a good approximation of the unquantized one. With 3-bit phase shifters, the performance is close to that of the unquantized system in multiuser communications, where the performance is more sensitive to quantization errors. While the analysis in this paper is done assuming high-resolution quantization, simulations show that the result is accurate even for coarse quantization. [ABSTRACT FROM PUBLISHER]

A highly efficient surface plasmon resonance (SPR)-based DNA assay was developed, by employing noncovalently functionalized graphene nanosheets as a substrate, and enzymatic catalysis-induced polymerization as mass relay. The objective of this strategy was manifold: first of all, to sensitize the overall SPR output by in situ optimized electrogeneration of graphene thin-film, which was characterized by atomic force microscopic topography; secondly, to regulate the self-assembly and orientation of biotinylated capture probes on nickel-chelated nitrilotriacetic acid (NTA) scaffolds, that anchored onto graphene-supported pyrenyl derivatives; and lastly, to synergize the signal amplification via real-time conversion of the additive aniline into polyaniline precipitation by horseradish peroxidase-tagged reporters. With this setup, a precise and replicable DNA sensing platform for specific targets was achieved with a detection limit down to femtomolar, thus demonstrating a beneficial exploration and exploitation of two-dimensional nanomaterials as unique SPR infrastructure. The possibility of such ″bottom-up″ architecture mounted with ″top-down″ weight reactor would be most likely extensible and adaptable to protein determinations. [ABSTRACT FROM AUTHOR]

To develop a sensitive and accurate method for the fingerprint study and transfer rule of chemical constituents from Ligusticum chuanxiong Hort and Gastrodia elata Blume to Tianshu capsule in productive process, a high performance liquid chromatography coupled with diode-array detection and electrospray ionization quadrupole time-of-flight mass spectrometry (LC/QTOF-MS) method was established for analysis. The reference fingerprints of aqueous extract intermediate of medicinal material, alcohol extract intermediate of medicinal material and Tianshu capsule was established. The methodology was studied and the similarity was more than 0.99. The chromatographic methods demonstrated a good precision, repeatability, stability, with relative standard deviations of less than 3% for relative retention time and relative peak area. According to these fingerprints, some chemical constituents in the fingerprints were identified or tentatively identified based on their retention time, exact molecular weight and literature. Among of them 26 constituents were from Ligusticum chuanxiong Hort and nine components were from Gastrodia elata Blume. 25 out of 26 compounds had entered a transfer process and 17 compounds were transferred from intermediates to the final preparation, the Tianshu capsule. Thus, it is reasonable enough to use this transfer process to demonstrate the production technology. To sum up, this method is sensitive, accurate and useful, and it could provide us an approach to evaluate the production technology of Tianshu capsule. [ABSTRACT FROM AUTHOR]

In this work, a series of Mo/γ-Al 2 O 3 catalysts have been prepared by using Mo species enwrapping with dodecyltrimethylammonium bromide (DTAB) as the novel precursors for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). The objective of this work is to get a deep insight into the effect of the Mo precursors on the size and morphology of the active phases and HDS activity. DTAB as the organic additive for the preparation of Mo precursors can dominate the nature of precursor solution and adjust the metal-support interaction so as to control the dispersion and morphology of the active phases. It is clearly shown that the addition of DTAB can effectively decrease the strong interaction between the Mo species and γ-Al 2 O 3 support and favor to tune the size and morphology of MoS 2 nanoparticles. The optimum molar ratio of DTAB/Mo is 3/5 and the corresponding catalyst shows the highest sulfidation degree with the most suitable stacking layer numbers and the shortest length of MoS 2 and thus exhibits the best HDS performance. Our work explores the important roles of organic additive to adjust the metal-support interaction and control the morphology of active phases and provides an effective precursor which can be used widely to prepare supported catalysts. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effect of bavachin treatment on A375 cells and the regulation of melanin synthesis. The cultured A375 cells in vitro were treated with bavachin; and the effect of bavachin on cell activity, tyrosinase (TYR) activity and melanin synthesis were respectively tested by the MTT assay, L-dopa oxidation assay and the NaOH lysis assay. The expression levels of TYR and c-Jun N-terminal kinases (JNK) proteins were tested by western blot analysis. The expression levels of TYR, tyrosinase-related protein-1 (TRP-1), TRP-2, extracellular signal-regulated kinase 1 (ERK1), ERK2 and JNK2 mRNA were tested by the reverse transcription-polymerase chain reaction assay. Simultaneously, the effect of estrogen receptor inhibitor (ICI182780) and ERK pathway inhibitor (U0126) was also tested on A375 cells following bavachin. The safe dose of bavachin significantly inhibited melanin synthesis and TYR activity. Bavachin (10 µmol/l) inhibited the expression of TYR and JNK proteins, and the expression of TYR, TRP-1, TRP-2, ERK1, ERK2 and JNK2 mRNA in A375 cells. ICI182780 and U0126 could significantly reverse the bavachin treatment on the protein expression levels and the mRNA expression of TYR, TRP-1, TRP-2, ERK1, ERK2 and JNK2. In conclusion, bavachin inhibited the synthesis of melanin on A375 cells by inhibiting the protein and mRNA expression of TYR, TRP-1, TRP-2, ERK1, ERK2 and JNK2. [ABSTRACT FROM AUTHOR]

We explore the QCD phase diagram by constructing a holographic QCD model using the Einstein-Maxwell-Scalar system. The chiral transition is investigated by adding a probe scalar and the confinement transition is studied by adding a probe string into the system. By interpreting the black hole phase transition in the bulk spacetime as the quarkyonic transition in the dual QCD theory and introducing the bypass mechanism for the deconfinement transition, we give an explanation why chiral symmetry breaking and deconfinement transition lines coincide with each other despite their different physical origins. [ABSTRACT FROM AUTHOR]

FDU-12 silica with highly ordered face-centered cubic mesoporous structure is developed as support to prepare Mo/FDU-12 catalysts for hydrodesulfurization (HDS) of dibenzothiophene (DBT). A series of Mo/FDU-12 catalysts are synthesized by using incipient wetness impregnation method with different MoO3 loadings (6, 8, 10, 12, and 15 wt.%). The objective of this work is to explore the pore confinement effect of FDU-12 mesochannels on the MoS2 morphology with various metal loadings. It is found that, as increasing MoO3 loadings from 6 to 15 wt.%, the MoS2 nanocrystallites transform from monolayer to multilayer and the morphology changes from straight layered to curved and then to ring-like and finally to spherical-like morphology due to the restriction of cage-like pore channels of FDU-12 support. The HDS results show that the catalytic activity increases first and then decreases with the best HDS performance at the MoO3 loading of 10 wt.%. In addition, we compared the HDS activity of Mo catalyst supported on FDU-12 with that on the commercial γ-Al2O3 and SBA-15; the result exhibits that FDU-12 is superior to the other two supports due to its large pore size and ordered three-dimensional open pore channels. [ABSTRACT FROM AUTHOR]

The pursuit of more specific and sensitive response is a perpetual goal for modern bioassays. This work proposed a novel label-free strategy about redox-related mass effect based on the surface plasmon resonance (SPR) technique for ultrasensitive determination of DNA. The protocol starts with the modification of SPR gilded disk with the capture DNA ( c DNA). After the conjugation of immobilized c DNA with the target DNA ( t DNA), the hybridization chain reaction was triggered by the introduction of mutual partial complementary primers to elongate the terminal into a nanoscale duplex. As it is reported that porphyrin could intercalate into the grooves of the double-stranded DNA ( ds DNA) scaffold, multiple positive-charged Fe III meso - tetra ( N -methyl-4-pyridyl) porphine (FeTMPyP) with symmetric structure were uptaken for in situ formation of porphyrin- ds DNA complex. Given FeTMPyP a highly efficient catalysis for the peroxide reduction, its presence as a biomimetic cofactor was validated via circular dichroism and UV–vis spectroscopy, demonstrating a tight binding as well as high catalytic activity and stability. Using 4-chloro-1-naphthol as a proton donor, the catalytic reduction of H 2 O 2 would oxidize it into insoluble benzo-4-chloro-hexadienone, which simultaneously deposited on the heterogeneous interface, leading to a significant amplification in both SPR response and topological height profile. The signal increment was proportional to the concentration of t DNA, thus an ultrasensitive SPR-based DNA assay was developed with a linear range over four orders of magnitudes and a sub -femtomolar detection limit of 0.73 fM. The developed methodology exemplifies a different way of thinking about mass-sensing modes, extending conventional SPR-based DNA analysis to relevant biomedical applications. [ABSTRACT FROM AUTHOR]

Histone deacetylase (HDAC) inhibitors are an emerging class of targeted therapy against cancers. Thailandepsin A (TDP-A) is a recently discovered class I HDAC inhibitor with broad anti-proliferative activities. In the present study, we aimed to investigate the potential of TDP-A in the treatment of breast cancer. We demonstrated that TDP-A inhibited cell proliferation and induced apoptosis in breast cancer cells at low nanomolar concentrations. TDP-A activated the intrinsic apoptotic pathway through increase of pro-apoptotic protein Bax, decrease of anti-apoptotic Bcl-2, and cleavage of caspase-3 and poly (ADP-ribose) polymerase (PARP). TDP-A also induced cell cycle arrest at the G2/M phase, and promoted the production of reactive oxygen species (ROS). We have successfully encapsulated TDP-A into our recently developed disulfide cross-linked micelles (DCMs), improving its water solubility and targeted delivery. TDP-A loaded DCMs (TDP-A/DCMs) possess the characteristics of high loading capacity (>20%, w/w), optimal and monodisperse particle size (16 ± 4 nm), outstanding stability with redox stimuli-responsive disintegration, sustained drug release, and preferential uptake in breast tumors. In the MDA-MB-231 breast cancer xenograft model, TDP-A/DCMs were more efficacious than the FDA-approved FK228 at well-tolerated doses. Furthermore, TDP-A/DCMs exhibited synergistic anticancer effects when combined with the proteasome inhibitor bortezomib (BTZ) loaded DCMs (BTZ/DCMs). Our results indicate that TDP-A nanoformulation alone or in combination with BTZ nanoformulation are efficacious against breast cancer. [ABSTRACT FROM AUTHOR]

This article reports a novel method for preparing supported NiW hydrodesulfurization (HDS) catalysts with tunable size and morphology of active phases to achieve highly selective HDS performance in hydro-upgrading fluid catalytic cracking (FCC) naphtha. The proposed approach features the combined use of W-based hybrid nanocrystals (HNCs) as the W precursor and the promoting effect optimization of Ni promoter. The W-based HNCs synthesized under mild hydrothermal conditions are monodispersed particles with an average size of ca. 2 nm and show a core–shell structure with W 6 O 19 2− as the inorganic core and short-chain quaternary ammonium cations as the organic shell. The use of W-based HNCs facilitates the formation of highly dispersed W species and WS 2 active phases with enhanced stacking, thus yielding a larger number of accessible Ni–W–S edge sites upon nickel impregnation. Moreover, we found that the advantageous W dispersion in the HNC-derived monometallic catalyst precursor allows further modification of the size and morphology of the active phase via the optimized incorporation of Ni promoter, leading to the formation of Ni–W–S edge sites with a lower percentage of brim sites and thereby resulting in considerably higher selective HDS performance for FCC naphtha than its counterpart prepared by the conventional impregnation method. The proposed approach makes it easy to tune the size and morphology of WS 2 nanoparticles, shedding light on the rational design of supported WS 2 catalysts for FCC naphtha selective HDS. [ABSTRACT FROM AUTHOR]

In this paper, we consider variable-rate transmission over a slowly varying multiple-input multiple-output (MIMO) channel with a decision feedback receiver. The transmission rate is adapted to the channel by dynamically assigning bits to the subchannels of the MIMO system. Predictive quantization is used for the feedback of bit loading to take advantage of the time correlation inherited from the temporally correlated channel. Due to the use of decision feedback at the receiver, the bit loading is related to the Cholesky decomposition of the channel Gram matrix. Assuming the channel is modeled by a slowly varying Gauss–Markov process, we show that the nested submatrices generated during the process of Cholesky decomposition can be updated as time evolves. Based on the update, we derive the optimal predictor of the next bit loading for predictive quantization. Furthermore, we derive the statistics of the prediction error, which are then exploited to design the quantizer to achieve a smaller quantization error. Simulations are given to demonstrate that the proposed predictive quantization gives a good approximation of the desired transmission rate with a low feedback rate. [ABSTRACT FROM PUBLISHER]

In this paper we consider variable-rate transmission for time-correlated MIMO (multi-input multi-output) channels with limited feedback. The number of bits loaded on each subchannel of the MIMO system is dynamically assigned according to the current channel condition and fed back to the transmitter. As the channel is time-correlated, bit loading is a vector signal that is also time-correlated. We propose to feedback bit loading using predictive coding, which is known to be a powerful quantization technique when the underlying signal is correlated in time. Assuming the channel is a first-order Gauss-Markov random process, we derive the predictor for the bit loading to be coded and analyze the corresponding prediction error variance when the channel is varying slowly. By exploiting the prediction error variance, we adapt the quantizer of the prediction error to have a smaller quantization error. Furthermore we show that the prediction error variance is proportional to a term that depends only on the time-correlation coefficient. This leads to the conclusion that, a codebook that is designed for a particular time correlation coefficient can be easily modified to a codebook for a different correlation coefficient without redesign. Simulations are presented to demonstrate that the proposed predictive coding can achieve a very good approximation of the desired transmission rate with a very low feedback rate. [ABSTRACT FROM PUBLISHER]

Adsorption is the primary mechanism of antibiotic removal in wastewater treatment plants, wherein the extracellular polymeric substances (EPS) of the activated sludge play an important role. Due to their complex characteristics, the effect of EPS components on antibiotic adsorption is unknown. Therefore, in this study, the role of main components of EPS in antibiotic adsorption was explored using enzymatic treatment. The results revealed that proteinase K and α-amylase can efficiently hydrolyse the proteins and polysaccharides of EPS. The protein content of EPS reduced from 31.25 mg/g VSS to 21.53, 18.75, and 10.76 mg/g VSS, after treatment with proteinase K, α-amylase and their combination, respectively; the polysaccharides content also observed a similar decrease from 15.20 mg/g VSS to 8.22, 7.83, and 6.03 mg/g VSS, respectively. The humic substance in EPS was stable during enzymatic treatment. The equilibrium adsorption capacity of activated sludge treated by enzyme for trimethoprim (TMP)- a typical antibiotic, was significantly increased from 2.19 μg/g VSS to 4.68, 5.34, and 8.36 μg/g VSS after treatment with proteinase K, α-amylase and their mixture. The adsorption process was adequately described by pseudo-second-order kinetic model. A multivariable linear regression model was subsequently used to quantify the adsorption capacity of activated sludge for TMP considering the concentration of EPS components. The modelling and validated results showed that the model could satisfactorily predict the TMP adsorption capacity. The results of this study can provide new insights into the role of EPS on antibiotic transformation in biological wastewater treatment systems. [Display omitted] • Enzymatic treatment was used to disintegrate extracellular polymeric substances. • The equilibrium adsorption capacity of sludge treated by enzyme was determined. • A model was developed to quantify the adsorption capacity of EPS components. • The model could predict the TMP adsorption capacity with EPS components. [ABSTRACT FROM AUTHOR]

Abstract: A series of mesoporous sieves with different pore diameters and structures have been controllably synthesized by adding variable amounts of swelling agent 1,3,5-trimethylbenzene in the preparation process for SBA-15. NiMo catalysts supported by mesoporous sieves are prepared by using the newly proposed Mo-based organic–inorganic hybrid nanocrystals as precursors to load Mo and subsequently using wetness impregnation to load Ni. The hydrodesulfurization (HDS) activity of these obtained catalysts is evaluated in a continuously flowing tubular fixed-bed microreactor using 1wt% dibenzothiophene (DBT) in heptane as a model compound. The results show that HDS ratio has gradually increased as the pore diameter of supports is enlarged from 7 to 11nm with the mesostructure keeping an ordered two-dimensional hexagonal symmetry. When the structure is in the intermediate stage of structural transition from ordered hexagonal mesostructure to mesocecullar structure, HDS ratio is decreased dramatically due to the disordered and collapsed structure to block the pore channels. After the mesocecullar structure with three-dimensional open pore channels is formed which is more convenient for the molecular diffusion, HDS ratio has increased again as a result. It is concluded that both the pore size and window size connecting the adjacent pores play an important role in the HDS activity but the window size is of more significant importance, which is the key point for the enhanced catalytic performance. [Copyright &y& Elsevier]

Highlights: [•] High quality of the photonic band gap (PBG) films was obtained within 5min. [•] The PBG films were fabricated by the electrophoretic deposition (EPD) process. [•] Quality of the PBG film was affected by the applied voltage strategies. [•] High quality of the PBG films was fabricated by the step-wise decreasing voltage strategy. [Copyright &y& Elsevier]

Lipid deposition in the kidney can cause serious damage to the kidney, and there is an obvious epithelial–mesenchymal transition (EMT) and fibrosis in the late stage. To investigate the interventional effects and mechanisms of phenolic compounds from Mori Cortex on the EMT and fibrosis induced by sodium oleate-induced lipid deposition in renal tubular epithelial cells (NRK-52e cells), and the role played by CD36 in the adjustment process, NRK-52e cells induced by 200 μmol/L sodium oleate were given 10 μmoL/L moracin-P-2″-O-β-d-glucopyranoside (Y-1), moracin-P-3′-O-β-d-glucopyranoside (Y-2), moracin-P-3′-O-α-l-arabinopyranoside (Y-3), and moracin-P-3′-O-[β-glucopyranoside-(1→2)arabinopyranoside] (Y-4), and Oil Red O staining was used to detect lipid deposition. A Western blot was used to detect lipid deposition-related protein CD36, inflammation-related protein (p-NF-κB-P65, NF-κB-P65, IL-1β), oxidative stress-related protein (NOX1, Nrf2, Keap1), EMT-related proteins (CD31, α-SMA), and fibrosis-related proteins (TGF-β, ZEB1, Snail1). A qRT-PCR test detected inflammation, EMT, and fibrosis-related gene mRNA levels. The TNF-α levels were detected by ELISA, and the colorimetric method was used to detects SOD and MDA levels. The ROS was measured by flow cytometry. A high-content imaging analysis system was applied to observe EMT and fibrosis-related proteins. At the same time, the experiment silenced CD36 and compared the difference between before and after drug treatment, then used molecular docking technology to predict the potential binding site of the active compounds with CD36. The research results show that sodium oleate can induce lipid deposition, inflammation, oxidative stress, and fibrosis in NRK-52e cells. Y-1 and Y-2 could significantly ameliorate the damage caused by sodium oleate, and Y-2 had a better ameliorating effect, while there was no significant change in Y-3 or Y-4. The amelioration effect of Y-1 and Y-2 disappeared after silencing CD36. Molecular docking technology showed that the Y-1 and Y-2 had hydrogen bonds to CD36 and that, compared with Y-1, Y-2 requires less binding energy. In summary, moracin-P-2″-O-β-d-glucopyranoside and moracin-P-3′-O-β-d-glucopyranoside from Mori Cortex ameliorated lipid deposition, EMT, and fibrosis induced by sodium oleate in NRK-52e cells through CD36. [ABSTRACT FROM AUTHOR]

This paper presents a nontraditional power supply system for lasers in which an active compensated pulsed alternator (ACPA) drives the flashlamp load directly instead of the capacitor groups. However, the delivered power and pulsed width of the ACPA are two pivotal machine output parameters, which are determined by the flashlamp load. In other words, the characteristics of the flashlamp load must be elaborately considered during the design process of ACPA. In this paper, the structure of a new single-phase iron-core nonsalient pole ACPA is proposed, which couples the flashlamp load. The theory and advantages of ACPA are also introduced. The characteristics of the transient magnetic field distributions are calculated by finite-element analysis to verify the electromagnetic programming design of ACPA. A circuit model of the power supply system is then established to simulate the performance. Some simulation waveforms are obtained and explained. [ABSTRACT FROM PUBLISHER]

Abstract: In this work, the composites of LiBH4 and AlF3 were prepared and their hydrogen storage properties were investigated. The AlF3 addition to LiBH4 resulted in significant decreases in dehydrogenation temperature. All the xLiBH4 +AlF3 (x =1, 2, 3, 5) composites started to release hydrogen from about 100°C. The dehydrogenation of the composites was accomplished through several steps, depending on the molar ratio of LiBH4 to AlF3. A new phase Li3AlF6 was formed during the first dehydrogenation step, which further reacted with LiBH4. AlB2 was formed only at temperatures higher than 300°C. Li2B12H12 was detected as an intermediate. The dehydrogenation reactions have significantly reduced and thus favorable enthalpy changes. However, the reversibility of the composites needs to be improved. [Copyright &y& Elsevier]