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Objective Less than half of eligible Chinese rural women have been screened for breast and cervical cancer. The objective of this study was to describe individual-level reasons for attending or not attending ‘two cancers’ screening using Andersen's Behavioral Model of Health Services Use. Study design Cross-sectional study. Methods The study sample was from the Health Services Survey in 2013 in Jiangsu, China. A total of 6520 rural women aged 36–65 years answered the questions on ‘two cancers’ screening participation and were included in the final analysis, which consisted of univariate and multivariate logistic regression. Results In the results of multivariate logistic regression, factors significantly associated with having ‘two cancers’ screening included educational level (odds ratio [OR] = 0.78, 95% confidence interval [CI] = 0.65–0.92), per capita household income (OR = 0.65, 95% CI = 0.58–0.73), availability of female medical faculty in township facilities (OR = 0.35, 95% CI = 0.28–0.42), quality of life (OR = 0.72, 95% CI = 0.58–0.90), being nulliparous (OR = 3.21, 95% CI = 1.96–5.26), and multiparous (OR = 1.91, 95% CI = 1.68–2.16). Conclusion To reduce inadequate screening service utilization of breast and cervical cancer in rural areas, efforts should be made not only to target the vulnerable rural women with lower income, lower educational level, and lower health conditions but also to further improve access to female primary-care providers. Strategies are also urgently needed to focus on nulliparous and multiparous women.

The novel COVID-19 outbreak has affected more than 200 countries and territories as of March 2020. Given that patients with cancer are generally more vulnerable to infections, systematic analysis of diverse cohorts of patients with cancer affected by COVID-19 is needed. We performed a multicenter study including 105 patients with cancer and 536 age-matched noncancer patients confirmed with COVID-19. Our results showed COVID-19 patients with cancer had higher risks in all severe outcomes. Patients with hematologic cancer, lung cancer, or with metastatic cancer (stage IV) had the highest frequency of severe events. Patients with nonmetastatic cancer experienced similar frequencies of severe conditions to those observed in patients without cancer. Patients who received surgery had higher risks of having severe events, whereas patients who underwent only radiotherapy did not demonstrate significant differences in severe events when compared with patients without cancer. These findings indicate that patients with cancer appear more vulnerable to SARS-CoV-2 outbreak. Significance: Because this is the first large cohort study on this topic, our report will provide much-needed information that will benefit patients with cancer globally. As such, we believe it is extremely important that our study be disseminated widely to alert clinicians and patients. This article is highlighted in the In This Issue feature, p. 747

Objectives In recent years, telemedicine has emerged in China to help address problems concerning access to and the cost of medical treatment. The aim of this study was to explore the factors influencing residents’ adoption of telemedicine services. Methods Using social cognitive theory, we analyzed individual and environmental factors that influence patients’ behavioral intentions with respect to telemedicine. We distributed questionnaires to patients who had used telemedicine in Dongtai, and 279 valid samples were collected. Results The reliability and validity were acceptable. Eight of the 9 hypotheses were supported at the 0.05 significance level. Motivation had positive correlations with self-efficacy and trust, self-rated health was positively correlated with trust, subjective norms were positively correlated with self-efficacy and trust, institution size was positively correlated with trust, and self-efficacy and trust were positively correlated with patients’ intentions to use telemedicine. Conclusions Motivation and subjective norms can promote behavioral intentions by promoting self-efficacy and trust, and self-rated health and institution size can promote behavioral intentions by promoting trust. These findings explain the antecedents of patients’ behavioral intentions to use telemedicine and support specific policy recommendations for the development of telemedicine services.

The organic-inorganic donor-acceptor (D-A) hybrid heterostructures, an emerging class of hybrid complexes containing semiconductive organic dyes and inorganic pigments at a molecular level, have displayed extraordinary optoelectronic properties and applications. Herein, we demonstrated that the combination of dipyridyl-naphthalene diimide tecton (DPNDI) with CuI (or AgOOCF3) resulted in two isostructural D-A hybrid heterostructures based on 1D [Cu8I14]6- or [Ag8I14]6- polyanions surrounded by an interwoven network of in situ N-methylated DPNDI cations. Due to the compact contact between these two semiconductive components by the charge-assisted anion-π and C–H⋯I hydrogen-bonding interactions, the obtained hybrid materials not only display high chemical stability but also exhibit high efficiency and moderate stability in the photoreduction of Cr(VI) upon visible light irradiation. The influences of various experimental conditions on the photocatalytic reactions including pH value and hole scavenger have been investigated. In addition, the possible mechanism studied shows that photogenerated electrons are the main active substances in the photoreduction of Cr(VI). This study suggests that constructing D-A hybrids heterostructures by two functional components with noncovalent interactions are promising for developing the hybrids used in the reduction of Cr(VI) in the future.

Donor-acceptor (D-A) hybrid heterostructures, an emerging class of crystalline hybrid complexes composed of semiconducting organic and inorganic components, have attracted much attention as photochromic materials. Among them, photochromic polyoxometalate/naphthalenediimide D-A hybrid heterostructures represent the most investigated ones, whose photochromic properties are strongly dependent on the structures of polyoxometalates and naphthalenediimides. Herein, we reported their photochromic properties are controlled by their moculelar packings, which were achieved by their diffusion methods. Eight polyoxometalate/naphthalenediimide D-A hybrid heterostructures have been synthesized by the combinations of metal salts (ZnSiF6·6H2O or Zn(ClO4)2·6H2O), heteropoly acid (H3PMo12O40 or H3PW12O40) and N,N-di (4-pyridyl)-1,4,5,8-naphthalene diimide (DPNDI) via two diffusion methods (A and B). Interestingly, single-crystal X-ray diffraction analyses reveal that they belong to three categories of isostructures with layered, sandwich and interpenetrating packing patterns. Their photochromic properties have been carefully investigated, and the impacts of polyoxometalates as well as packing patterns have also been discussed.

This work aimed to prepare a hydrogel film with antibacterial activity and excellent stability in enzymes as potential wound dressing. Using hyaluronic acid, carboxylated chitosan and gentamicin, antibacterial film HA-CC-GS was prepared through intermolecular covalent bonding. Surface morphology of film was evaluated by scanning electron microscope images. The film exhibited good water absorption capacity and appropriate water vapor permeation rate (WVPR), outstanding mechanical properties and remarkable resistance to enzymatic hydrolysis. The biocompatibility of the film was tested by CCK-8 assay, and the results showed that the viability of NIH3T3 cell was not affected by coculture with hydrogel film. In vitro antibacterial test indicated that the synthesized hydrogel film had obvious antibacterial properties. In addition, in vivo studies showed that antibacterial hydrogel film could protect wound from infection and promote wound healing. These results indicated that the prepared antimicrobial hydrogel films by cross-linking had great potential application in skin/tissue repair, suggesting as a hopeful wound dressing.

The combination of N, N′-dipyridyl-tetrachloroperylene diimide (4Cl-DPPDI) buliding blocks with lead iodides in the presence of hydrogen iodides led to a novel D-A hybrid heterostructure with segregated iodoplumbate anions and 2-D H-bonded 4Cl-DPPDI networks as electron donors and acceptors. Due to the compact anion-π interactions as well as small energy gaps between the donors and acceptors, persistent and stable radical anions are generated in such a unique complex triggered by natural-light irradiation, which thus exhibits a panchromatic absorption.

Room-temperature phosphorescence (RTP) has attracted much attention in the past decades due to its potential applications in optoelectronic devices and bioimaging. So far, most available RTP materials are pure inorganic or organic compounds, few are involved in the organic-inorganic hybrid complexes. The donor-acceptor (D-A) hybrid heterostructures are an emerging class of organic-inorganic hybrid complexes composed of semiconductive organic and inorganic tectons at the molecular level. For these unique hybrids, the primary properties are photochromism and photoinduced electron transfers. Herein, we have demonstrated that the combination of naphthalene diimide (NDI) tectons bearing two divergently oriented pyridyl protons with three polyoxometalate (POM) anions (SiW12O404−, PW12O403− or PMo12O403−) resulted in three isostructural D-A hybrid heterostructures with an alternate arrangement of segregated POM anions and 1-D H-bonded NDI networks as electron donors and acceptors, respectively. Due to the compact contacts between POM anions and NDI tectons induced by charge-assisted anion-π interactions, not only the photochromic speeds of three D-A hybrid heterostructures have been enhanced, but more interestingly their RTP emissions of have also been switched on, and their photoluminescence quantum yields are dependent on anion-π interaction strengths.

Microstructure and properties of the spray formed 7075 alloy with various heat treatments were studied by using tensile tester, transmission electron microscope and scanning electron microscope. The results show that the tiny precipitates distributed homogeneously in matrix can increase the ultimate tensile strength (UTS). The disconnected precipitates at grain boundary and wide precipitate free zones can improve the corrosion resistance of the alloy. Both strength and corrosion resistance of the alloy can be improved by retrogression and re-aging (RRA) processes. Especially, the U–RRA–H process can increase the UTS up to 791 MPa, which is higher than that after T6, T73 and conventional RRA treatments.

It was introduced that a very novel technique to prepare micro holes by direct casting method. And the micro hole (in diameter of 0.22 mm) with very large aspect ratio (as large as 1800) was successfully prepared. And anticipate to produce new functional material.

The main purpose of the present study was to examine the time-dependent alterations in the endothelial cell density that occur in the first 180 days after irradiation of the spinal cord and the functional role of these alterations in the spinal cord blood flow. An irradiated cervical spinal cord rat model (C2-T2 segment) was generated using a (60)Co irradiator to deliver 30 Gy. A significant loss of forelimb motor function was observed 180 days post-irradiation. The number of neurons in the anterior horn of the spinal cord began to decrease significantly 3 days post-irradiation compared with normal controls, reaching the lowest number at 90 days post-irradiation. A significant reduction in the endothelial cell density was observed from 14 days post-irradiation in the white matter and from 3 days post-irradiation in the gray matter. The lowest endothelial cell density was reached at 30 days post-irradiation in the white matter and at 60 days post-irradiation in the gray matter. A significant reduction in the microvessel density was observed from 3 days post-irradiation in both the white matter and the gray matter. The lowest microvessel density was reached at 90 days post-irradiation in both the white matter and the gray matter. A significant reduction in the relative magnitude of spinal cord blood flow was observed from 21 days post-irradiation. The lowest relative magnitude of spinal cord blood flow was reached at 90 days post-irradiation. We did not find any evidence of demyelination. The results revealed that a single 30-Gy irradiation dose resulted in impaired forelimb motor function, a decreased number of neurons, and reduced endothelial cell density, microvessel density and relative magnitude of spinal cord blood flow. However, a 30-Gy single-dose irradiation was not sufficient to induce demyelination in the rat spinal cord.

The multiple modes of Rayleigh waves (R-waves) or leaky Lamb waves (L-waves) may be present in the activated and/or the back-scattered wave fields. The presence of these waves in the wave fields is related to the source and the cavity depths. Two types of layered media are used to investigate the influences of the source and the cavity depths. One is the layered half space where the half space is stiffer than all the overlying layers; the other is the pavement system where there is significant velocity contrast between layers and the shear velocity of layers decreases with the layer depth. The discrete displacement expressions developed for spherical point sources are used to study the effects of the source depth on the excitability and the propagation behavior of R-waves or leaky L-waves. In layered half spaces, the multiple modes of R-waves can be activated by the sources within a certain depth. The effective phase velocity of these activated modes is derived. In pavement systems, the leaky L-waves can be activated by the sources at any depth. The discrete displacement expressions of the scattered waves are derived and used to evaluate the effects of the cavity depth on the presence of R-waves or the leaky L-waves in the back-scattered wave field.

A series of novel self-dispreading phenoxy carboxylic acid derivatives were designed and synthesized by I 2 catalyzed one-step reaction. Their structures were confirmed by IR, NMR, and HRMS. The derivatives can self-spread and float on the water surface. Preliminary bioassays showed that some compounds, 3i – 3p , had excellent herbicidal activities against water hyacinth. This strategy provided a novel approach for the water hyacinth control.

Although several techniques have been described for closing oropharyngocutaneous fistulas (OFs), large OFs remains a challenge. This clinical study assessed outcomes following the use of folded extensive supraclavicular fasciocutaneous island flaps (SFIFs) to close large OFs. Extensive folded SFIFs were designed to close large OFs following oropharyngeal cancer ablation in 11 patients (8 men, 3 women; mean age: 53.5 years). Fistula size ranged from 3.0 × 1.5 to 4.0 × 2.0 cm and skin paddle size ranged from 10 × 6 to 12 × 7 cm. SFIFs provided both inner and outer linings for OFs. All flaps survived, head and neck appearance was satisfactory, and no patient experienced a major complication. All patients resumed an oral diet and eventually regained normal speech abilities. No fistula recurrence or stricture developed after 6–18 months of follow-up. The folded extensive SFIF is a simple and reliable flap preferred for the reconstruction of large OFs.

An (Mg 0.585 Cu 0.305 Y 0.11 ) 95 Be 5 bulk metallic glass (BMG) with high strength was fabricated by conventional Cu-mold casting method. The phase structure, thermal stability and microstructure of the BMG were investigated by using X-ray diffraction, differential scanning calorimetry, transmission electron microscopy and scanning electron microscopy. The results show that the quaternary (Mg 0.585 Cu 0.305 Y 0.11 ) 95 Be 5 BMG with 3 mm in diameter exhibits obvious glass transition T g of 429 K and a wide supercooled liquid region Δ T x of 53 K. Meanwhile, the phase-separated regions characteristic of Cu–Y–Be glass containing nanometer CuY crystals are heterogeneously distributed in the Mg–Cu–Y glassy matrix in the as-cast samples. Under uniaxial compressive loading, the samples with 1, 2 and 3 mm in diameter show high strength up to 959, 955 MPa and 954 MPa, respectively. The sample-size independence of fracture strength was for the first time found in the Mg-TM–RE metallic glasses. The effects of Be addition on phase separation and mechanical properties for Mg–Cu–Y alloy system were discussed.

In homogeneous half spaces excited by small buried, spherically symmetric P-wave sources, Rayleigh waves (R-waves) could be generated. The effects of the source depth on the induced wave pattern and propagation behavior of R-waves are analyzed using the thin layer method. When a cavity is present in a homogeneous half space, R-waves could be formed in the scattered wave field. It is found that the energy of R-waves in the incident (direct) surface wave-field is related to the ratio of the source depth to the wavelength of R-waves; R-waves have relatively strong energy when the ratio is less than 1; the buried source induced R-waves approximately travel at the velocity of the planar R-waves in the range of the offset beyond about one wavelength; the energy of R-waves in the back-scattered surface wave-field depends on the ratio of the depth of cavity to the wavelength of R-waves; and for the case of the cavity presented at depths less than one wavelength, R-waves can be clearly observed in the back-scattered wave field. The results are helpful for selecting the source depth and the frequency component in seismic surveys and interpreting both the incident wave and the scattered wave patterns.

Based on the Betti–Rayleigh reciprocity theorem and the thin layer method (TLM), the discrete analytical displacement expression of Rayleigh waves scattered from heterogeneities in layered half spaces are presented. A parametric study on the scattering of Rayleigh waves is conducted for homogeneous half spaces with rectangular cavities present in the far field. For cavities that are long in the direction of wave propagation, the theory of Lamb waves in free plates is used to explain the propagation behavior of the waves above cavities. Some numerical simulations are used to verify the analyses. In order to establish the relationship between the depth of cavity and the wavelength, the spectra in the frequency domain are converted into ones in the wavelength domain. Effects of wave scattering on the spectral pattern in the offset-wavelength domain are investigated. The results show that the scattering of Rayleigh waves is not only related to the dimensionless location parameters ht/λR and h/λR but also ω2, where ht, h, λR and ω denote the depth and the height of the cavity, the wavelength of Rayleigh waves and the angular frequency, respectively. For long cavities, the near and the far faces of cavity can be roughly located from the “ripples” of the spectra and changes in the energy in the offset-wavelength domain and the depth of the cavity can be estimated from the critical wavelength associated with the onset of disturbance in the spectra above the cavity.

This study evaluates the outcome of superficial musculoaponeurotic system (SMAS) and allograft dermal matrix (ADM) preventing facial deformity and Frey's syndrome following total parotidectomy. Forty-six patients with benign parotid tumors, who underwent a total parotidectomy, were randomly assigned to four groups. Control group consisted of 12 patients; AMD group consisted of 10 patients underwent intraoperative placement of ADM within the parotid bed; SMAS group consisted of 11 patients underwent SMAS fold flaps repairing parotid bed; and SMAS plus AMD group consisted of 13 patients underwent intraoperative placement of ADM within the parotid bed and repairing parotid bed with SMAS fold flaps. Twelve months of follow-up was taken after the treatment, the rates of satisfaction with the post-operative facial contour were 33.3%, 40.0%, 91.9% and 100% respectively in the control group, AMD group, SMAS group and SMAS plus AMD group, and the difference between the SMAS plus AMD group and the former two groups was statistically significant ( P P

In the wave field induced by active sources, the observed phase velocity of surface waves is influenced by both mode incompatibility (i.e. non-planar spread of surface waves is idealized as plane waves) and body waves. Effects of sources are usually investigated based on numerical simulations and physical models. Several methods have been proposed to mitigate the effects. In application, however, these methods may also have difficulties since the energy of the body waves depends on soil stratification and parameters. There are multiple modes of surface waves in layered media, among which the higher modes dominate the wave field for soils with the irregular shear velocity profiles. Considering the mode incompatibility and the higher modes, we derive analytical expressions for the effective phase velocity of the surface waves based on the thin layer stiffness method, and investigate the effects of the body waves on the observed phase velocity through the phase analysis of the vibrations of both the surface waves and the body waves. The results indicate that the effective phase velocity of the surface waves in layered media varies with the frequency and the spread distance, and is underestimated compared to that of the plane surface waves in the spread range less than about one wavelength. The oscillations that appeared in the observed phase velocity are due to the involvement of the body waves. The mode incompatibility can be ignored in the range beyond one wavelength, while the influence range of the body waves is far beyond one wavelength. The body waves have a significant influence on the observed phase velocity of the surface waves in soils with a soft layer trapped between the first and the second layers because of strong reflections.

The vibration load caused by the impact and explosion in construction exerts great influence on the surrounding earth. Therefore, the safe operating condition of gas pipeline is seriously influenced. For the first time, by use of smart microseismic monitoring system, such vibration caused by the impact and explosion is monitored and analyzed. First, it reveals the transmission law of vibrating wave forms. Second, the coupling calculating models of pipeline earth under the influence of vibration is built. Finally, the characteristics of exerted force and transformation of earth-pipeline system are analyzed. According to these microseismic data obtained from the spot and numerical simulation method, the dynamic response of underground pipeline under compound vibration is studied; nonlinear mathematical model theory and method for coupling effects of earth and pipeline are built; the effects of vibration to pipeline are assessed; the feasible assessing method of safe operating condition of gas pipeline under vibration is explored and developed.

Electrochemical processes of solid indirubin and its sulfonated form were comparatively studied in aqueous buffers by cyclic voltammetry and long-path-length thin-layer UV–vis spectroelectrochemistry, using a carbon paste working electrode with or without indirubin particles attached. The two forms of indirubin gave similar voltammetric features as well as main reaction products. Alkaline pH of electrolyte generally had a negative effect on both the reaction systems, compared with the acidic pH. Electro-reduction of both indirubins produced their leuco forms, which can be oxidized back to the initial reactants by oxygen. In the alkaline buffers the leuco-indirubin (not sulfonated) may form aggregates with poor solubility and poor electrochemical reactivity. Electro-oxidation of both indirubins led to the irreversible formation of isatin (sulfonated or not). An EC and ECE mechanisms are proposed for the reduction and the oxidation, respectively, of indirubin in two forms. The combination of solid state and solution phase spectroelectrochemistry shows the advantage of providing multidimensional information for reaction mechanism

This paper focuses on the high energy proton irradiation effect of InAs/GaAs multilayers quantum-dot (QD) wafer and photodetector. With high energy proton path simulation, the releases of proton energy and trap distribution in QD multilayers are predicted well. Treated by 1 and 3 MeV protons, all protons almost penetrate the multilayers of QD structures and stop deeply in GaAs substrate. InAs QD multilayer structures/Infrared photodetector have been irradiated by protons with different energies (1 and 3 MeV) and doses (1 × 10 9 ∼ 1 × 10 13 protons/cm 2 ). The photoluminescence (PL) and photoresponsivity (PR) spectrum of samples were measured and discussed with as grown and post irradiation.

Two novel conjugated imino-π-extended tetrathiafulvalenes with p-iminobenzene, N,N′-bis(4,5-bis(methylthio)-1,3-dithiol-2-ylidene)benzene-1,4-diamine (1) and N,N′-bis(4,5-bis(ethylenedithio)-1,3-dithiolo-2-ylidene)benzene-1,4-diamine (2), have been synthesized and characterized by NMR, IR, MS and X-ray single-crystal diffraction. Both the two targets adopt chair-like conformation, and the central rings of p-iminobenzene moieties of the two molecules are severely twisted from the planarity of two dithiole rings, respectively. The UV–vis spectra of 1 and 2 show the lowest-energy absorption bands caused by the HOMO–LUMO one-electron promotion. Cyclic voltammetry (CV) measurements show only one, two-electron irreversible oxidation picks. These experimentally estimated energy levels of the frontier orbital of 1 and 2 (EHOMO 1: = −5.45, 2: −5.47 eV) are in good agreement with those obtained from DFT calculations (EHOMO 1: = −5.5, 2: = −5.3 eV). The high HOMO–LUMO gaps of 1 (4.05 eV) and 2 (4.00 eV) indicate high kinetic stability of the title compounds.

UV-vis and fluorescence spectra for interaction silver(I) ion with tryptophan (Trp) have been studied. The influence of pH of media, multicomponent concentration, including amino acids, silver(I) ion, formaldehyde, sodium dodecyl sulfate (SDS), and trihydroxymethylaminomethane (Tris) as well as temperature, illumination, time, etc. on reaction were investigated, and the mechanism of reaction has been explored. The results shown that the optimum condition for the interaction between tryptophan and silver(I) ion were found.