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Early diagnosis of acute myocardial infarction (AMI) can significantly reduce mortality, which can be achieved by highly sensitive detection of AMI-specific cardiac troponin I (cTnI) biomarkers. Herein a highly sensitive...

Objective: To determine the prevalence of food allergy (FA) and intolerance and estimate associations with anxiety and depression in a diverse sample of young adults.Participants: Undergraduates at...

Objective To explore the survival value of cytoreductive partial nephrectomy (cPN) in elderly with metastatic renal cell carcinoma (EmRCC) and evaluate the characteristics of patients who benefit from cPN. Materials and methods This was a study including 6105 patients aged ≥65 years with metastatic renal cell carcinoma (RCC) queried from Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2015, among which 1264 patients underwent cytoreductive nephrectomy (CN), 78 patients underwent cPN and 1186 patients underwent cytoreductive radical nephrectomy (cRN). Kaplan-Meier (K-M) method and Cox proportional-hazards model (COX) were used to evaluate the survival prognosis. Overall survival (OS) was compared between groups using propensity score matching (PSM) to balance the effects of confounding factors such as general features and pathological features. At last, we constructed a nomogram visualization modelled by R language to predict survival. Results For patients with EmRCC, especially for male patients with tumors size ≤7 cm, N0 stage, or isolated metastases, cPN brought a better survival than cRN. Tumor size and N stage were independent risk factors affecting the survival of cPN patients. cPN for patients with tumor size >7 cm or N1 stage may present a higher risk of death. Conclusion The implementation of cPN for patients with EmRCC who meet specific clinical characteristics such as tumors size ≤7 cm, N0 stage, or isolated metastases seems to help improve the survival prognosis.

Purpose of Review The purpose of this study is to review racial and ethnic inequities in the incidence and prevention of healthcare-associated infections (HAIs) in the USA, identify gaps in the literature, and recommend future directions to mitigate these inequities. Recent Findings While some existing literature has identified the presence of racial/ethnic inequities in HAI incidence and outcomes, few studies to date have evaluated whether HAI prevention efforts have mitigated these inequities. Factors contributing to inequities in HAI prevention may include unconscious bias of healthcare professionals towards minoritized patients; socioeconomic and structural inequities disparately affecting minoritized communities; the racial segregation of quality healthcare through hospital price discrimination; divergent reimbursement rates between public and private insurers; policies or performance metrics which underfund and financially penalize safety-net hospitals; and insufficient research evaluating and addressing HAI inequities. Summary Expansion of the literature is needed to further interrogate root causes and evaluate the impact of interventions on racial/ethnic inequities in HAI incidence. Measures to mitigate inequities might include teaching healthcare workers how to recognize and mitigate unconscious biases, expanding community resources which address the social and structural determinants of health, increasing access to preventive health services, reforming federal and institutional policies to better support safety-net hospitals and disincentivize price discrimination, and improving diversity and inclusion within the health workforce.

Attempt to group the number of lymph nodes in a more ideal way to assess the value of lymph node dissection (LND) in the treatment of localized high-risk renal cell cancer (LH-RCC). The Surveillance, Epidemiology, and End Result database (SEER) was used to analyze LH-RCC patients who undergoing radical nephrectomy (RN) from 2011 to 2015. The X-tile software was performed to calculate the optimal grouping cut-off points for the number of removed lymph nodes and positive lymph nodes. The Nomogram model was constructed by R language to visually present survival rates of patients. Among 4917 cases of LH-RCC patients undergoing RN, there were 1835 patients treated with LND (37.32%) with the average survival time (AST) of 43.10 months (95% CI 41.91–44.29), which was superior than 40.52 months of patients who did not have LND (95% CI 39.26–41.78) (P

A simple and portable potentiometric immunoassay was designed for the quantitative detection of matrix metalloproteinase-7 (MMP7) in acute kidney injury and renal cancer on a copper ion-selective electrode (Cu-ISE). To construct such an assay system, a sandwich-type immunoreaction was initially carried out on monoclonal anti-MMP7 capture antibody-coated microplates by using an initiator DNA strand-labeled anti-MMP7 secondary antibody. Thereafter, a hybridization chain reaction (HCR) was used for the signal amplification between copper nanocluster-labeled two hairpin DNA probes. Accompanying the formation of the sandwiched immunocomplex, the labeled DNA initiator strand on the secondary antibody triggered the HCR between two alternating DNA hairpins to form a nicked double-helix with copper nanoclusters. The subsequent potentiometric measurement of copper ions released from the concatenated copper nanoclusters under acidic conditions was conducted on a portable handheld potentiometer. The immuno-HCR assay combined an easy-operation potentiometric assay with signal amplification by using an HCR-induced copper nanocluster concatemer. Under optimum conditions, the developed immuno-HCR assay exhibited a dynamic linear range of 0.01–100 ng mL−1 with a detection limit of 5.3 pg mL−1 and good reproducibility. Also, the immuno-HCR assay gave good anti-interfering capacity toward other biomarkers. The analysis for clinical human serum specimens revealed good accordance with the results obtained by an enzyme-linked immunosorbent assay. Importantly, our strategy is promising for enzyme-free and cost-effective analysis of low-abundance cancer biomarkers.

Hartmann testing method is still widely used for measuring the diopter of spectacle lens. However, its aperture measurement and resolution are limited by diffraction. This paper proposes a method to obtain full-aperture diopter distribution of spectacle lenses, including progressive addition lenses (PAL). The method uses a specially designed Hartmann testing plate for generating testing rays. The plate is rotated during measurement to overcome the diffraction limitation. Both simulation and experiment are carried out for verifying this method. The diopter measurement error of spherical power lens, cylindrical power lens, and PAL are less than 1% compared to the theoretical value in simulation. In the experiment, the deviation error is less than 2% for signal vision lens, when compared with the results obtained by an automated focimeter. The result shows that the proposed method can measure the full-aperture of diopter distribution for PAL.

The evolution of sex chromosomes in the XY or ZW systems shall lead to gene expression dosage problems, as in at least one of the sexes, the sex-linked gene dose has been reduced by half. It has been proposed, most notably by Susumu Ohno for mammals, that the transcriptional output of the whole sex chromosome should be doubled for a complete dosage compensation. However, due to the variability of the existing methods to determine the transcriptional differences between Sex chromosomes and Autosomes (S:A ratios) in different studies, whether clade-specific results are comparable and whether there is a more general model to explain dosage compensation states remain unanswered. In this study, we collected more than 500 public RNA-seq datasets from multiple tissues and species in major clades (including mammals, birds, fishes, insects, and worms) and proposed a unified computational framework for unbiased and comparable measurement of the S:A ratios of multiple species. We also tested the evolution of dosage compensation more directly by assessing changes in the expression levels of the current sex-linked genes relative to those of the ancestral sex-linked genes. We found that in mammals and birds, the S:A ratio is approximately 0.5, while in insects, fishes and flatworms, the S:A ratio is approximately 1. Further analysis showed that the fraction of dosage-sensitive housekeeping genes on the sex chromosome is significantly correlated with the S:A ratio. In addition, the degree of degradation of the Y chromosome may be responsible for the change in the S:A ratio in mammals without a dosage-compensation mechanism. Our observations offer unequivocal support for the sex chromosome insensitivity hypothesis in animals and suggest that the dosage sensitivity states of sex chromosomes is a major factor underlying different evolutionary strategies of dosage compensation.

Toroidal, spherocylindrical, ellipsoidal, and combined surfaces were used to correct astigmatism in aspheric spectacle lenses, and the differences among the proposed techniques were compared. Four astigmatic spectacle lenses were designed with the same optical parameters. A freeform measuring machine was used to evaluate posterior surfaces of aspheric spectacle lenses, and spherical and cylindrical power maps were generated and compared. The measured data were analyzed via commercial software. The toroidal lens helped to extend the clear vision range around the lens, and the ellipsoidal and spherocylindrical surfaces resulted in a more accurate centering of the lens around the optical axis of the eye, avoided astigmatism, and provided better visual perception.

Background To explore the survival value of cytoreductive partial nephrectomy (cPN) in elderly metastatic renal cell carcinoma (EmRCC).Methods RCC patients aged ≥65 years from 2010 to 2015 in The Surveillance, Epidemiology and End Result database (SEER) were analyzed using Kaplan-Meier (K-M) method and multivariate COX analysis. Propensity score matching (PSM) was performed to balance effects of confounding factors such as general features and pathological features. We were committed to study the long-term survival advantages of cPN patients, explore the appropriate population of cPN, and try to establish a Nomogram model to predict individual survival.Results In EmRCC patients, especially in male patients with tumors size ≦7cm, N0 stage, or isolated metastases, cPN brought a better survival than cytoreductive radical nephrectomy (cRN). Tumor size and N stage were independent risk factors affecting the survival of cPN patients, cPN in patients with tumor size >7cm or N1 stage may present a higher risk of death.Conclusions The implementation of cPN in EmRCC patients who meet specific clinical characteristics like tumors size ≦7cm, N0 stage, or isolated metastases seems to help improve the tumor outcomes.

To precisely measure the whole-surface characterization of freeform progressive addition lenses (PALs), considering the multi-optical-axis conditions is becoming particularly important. Spherical power and astigmatism (cylinder) measurements for freeform PALs, using a Hartmann–Shack wavefront sensor (HSWFS) are proposed herein. Conversion formulas for the optical performance results were provided as HSWFS Zernike polynomial expansions. For each selected zone, the studied PALs were placed and tilted to simulate the multi-optical-axis conditions. The results of two tested PALs were analyzed using MATLAB programs and represented as contour plots of the spherical equivalent and cylinder of the whole-surface. The proposed experimental setup can provide a high accuracy as well as a possibility of choosing 12 lines and positions of 193 measurement zones on the entire surface. This approach to PAL analysis is potentially an efficient and useful method to objectively evaluate the optical performances, in which the full lens surface is defined and expressed as the contour plots of power in different regions (i.e., the distance region, progressive region, and near region) of the lens for regions of interest.

To evaluate the value of nephrectomy for survival prognosis in renal cell carcinoma (RCC) patients with brain metastases (BM). There were 933 RCC patients diagnosed with BM in SEER database from 2010 to 2014. Kaplan–Meier method and Cox regression model were used to analyze the survival prognosis. The effect of nephrectomy on overall survival (OS) was analyzed by propensity score matching. The competitive risk model was performed to explore the relationship between surgery and cancer-specific survival (CSS), and the nomogram visualization model was established by R language to predict survival rate. BM accounted for 1.5% of newly diagnosed RCC patients and 11.1% of M1 stage patients with the median survival time of 5 months (95% CI 4.5–5.5). Age 45–65 years, tumor diameter > 10 cm and histologic type of clear cell renal cell carcinoma (ccRCC) were high risk factors for BM in RCC patients. Age, N stage, lung metastasis and nephrectomy were independent prognostic factors. Nephrectomy was beneficial for both OS and CSS for the analysis of 216 patients successfully matched. The nomogram model has a certain value in predicting the survival rate with the internal verification c-index of 0.727. Patients with high risk of BM (age 45–65 years, tumor diameter > 10 cm, histologic type of ccRCC) should emphasize brain imaging screening during follow-up. Nephrectomy may bring survival advantages for RCC patients with BM. Nomogram model based on nephrectomy can helps predicting the 1-, 2- and 3-year survival rates.

We employed two-dimensional convolution processing and spline interpolation methods to process the weight distributions (WDs) of the spherical and cylindrical power deviations, and assess their effect in designing progressive addition lenses (PALs), based on the minimized error function. Eight power deviation and astigmatism WDs were constructed with different convolution processing schemes and transition area widths connecting the high- and low-weight areas, respectively. Correspondingly, eight PALs were designed, simulated, machined, and evaluated by commercial software. The results show that the number of multiple convolution processing changes from 0 to 15, areas of the far and near areas increase by 35.7% and 76.5%, and maximum peripheral astigmatism increases from 0.75 to 1.5 addition power, respectively. When the width of the transition zone changes from 0 mm to 9 mm, the area of the far and near regions increase by 27.2% and 58.2%, respectively, and the maximum peripheral astigmatism increases from the original value of 1 addition power to 1.25 addition power, respectively.

The purpose of this study was to compare the optical properties of different astigmatic optical surfaces by direct physical measurement of their surface shapes. The back-surface heights of different astigmatic optical lenses were measured with a freeform measuring machine (FMM). In order to calculate the function of the part point cloud fitting surface for the dispersed data points of the astigmatic lenses, the measured shape data were modeled through surface fitting of a bicubic spline. The principal curvatures of each point on the surface were calculated, and the optical properties of each surface and their combinations were generated as contour plots using custom MATLAB routines. The fitting surface of the actual measurement points was compared with the design surface to determine the surface error. Analyses showed that this nonoptical method using an FMM can be used to effectively evaluate a cylindrical lens by surface height measurements alone. Compared to the optical measurement method, the optical properties derived directly from the surface shape can provide information not accessible by other methods. Therefore, this approach is potentially useful to clinicians who want to better understand the design of astigmatic optical lenses for making better recommendations to their clients.

The photonic crystals possess complex dispersion relation and the unusual dispersion leads to negative refraction. Based on negative refraction, three main physical phenomena, negative Goos–Hanchen displacement, inverse Doppler effect and abnormal Cherenkov radiation have been proposed. In this work, two abnormal physical phenomena are discussed. Firstly, the negative Goos–Hanchen shift displacement is simulated by using common FDTD method. The negative displacement is measured experimentally at the wavelength of 10.6 μm. Secondly, a novel phenomenon, the dual Doppler effect, in the simultaneous occurrence of both normal and inverse Doppler effect in one moving two-dimensional wedge-type photonic crystal with negative index is investigated by using spatial Fourier Transformation. This phenomenon is also simulated by an improved FDTD method. The results have potential applications in precision measurement, cloaking, sensor, radar deception and so on.

The dual Doppler effect, in the simultaneous occurrence of both normal and inverse Doppler effect in one moving two-dimensional wedge-type photonic crystal, is proposed. An improved finite-different time-domain algorithm is used to verify this phenomenon. The spatial Fourier Transformation has been applied to complex electrical field data to reveal the mechanism. The harmonics with negative spatial frequencies show a lagging phase evolution, while those with positive spatial frequencies show a front phase evolution. Different wedge-type photonic crystals are designed to filter out the required harmonics based on the systematic study of spatial Fourier Transformation and wave vector diagram. Our work paves a new way for Doppler cooling of atomic gases, radar deception, invisibility cloaks, microstructure dual frequency interferometer and so on.

In the present study, imatinib mesylate (IM) was used to induce resistance in the gastrointestinal stromal tumour (GIST) cell line, GIST-T1, to establish a stable resistant cell line. The growth characteristics and expression profile of the established cell line were compared with those of the parental cell line. Additionally, the resistance mechanism of the gastrointestinal stromal tumours was preliminarily investigated. The GIST-T1 cells were cultured in vitro, and the drug was administered in the logarithmic phase of cell growth using intermittent dosing with increasing concentrations to obtain a drug-resistant cell line by repeated induction. Differences in the biological behaviours of the parental cells and drug-resistant cells were examined, and changes in the expression profiles were compared in the two cell lines. The results showed that the IM-resistant GIST-T1 cell line (GIST-T1 IR) was successfully established. Analysis of the biological behaviours of the two cell lines revealed that the average doubling times of the parental cells and drug-resistant cells were 26.59 and 33.63 h, respectively. The results of a scratch migration assay revealed that the migration ability was enhanced in the GIST-T1 IR cells. The results of CCK-8 detection indicated that the half maximal inhibitory concentration values of the two types of cells were 10.5 and 42.0 µM, respectively, which represented an increase of ~4-fold in the GIST-T1 IR cells. Flow cytometric cell cycle analysis indicated that the numbers of cells in the G0/G1, S and G2 phases increased following the induction treatment. Taken together, an IM-resistant GIST T1 cell line was successfully established, which opens novel avenues for individualized tumour chemotherapy.

Photonic crystals have a great prospect in the field of integrated optics due to their high integration and low transmission loss. In this paper, a beam splitter based on the bandgap of photonic crystal is designed and demonstrated experimentally for polarization-dependent beam splitting. The simulated radiation patterns show excellent polarization purity, with a cross-polarization level above 20 dB. Furthermore, the angle deviation of the incident and the temperature change of device have slight impact on beamsplitting. Larger shifting range of incident wavelength is allowed. What is more, the range of medium radius with good splitting effect is relatively large, which reduces the difficulty of production and processing.

The influence of temperature on the reflectivity of symmetrical metal-cladding optical waveguide (SMCOW) is studied theoretically by means of single-factor investigation under spectral and angular interrogation mode of operation. The theoretical model for temperature dependence of reflectivity includes the temperature dependence of refractive index and thickness of guiding layer, the temperature dependence of the metal film thickness and metal-dielectric function. It is found that the effect of temperature on the reflectivity of SMCOW is mainly attributed to the temperature dependence of refractive index and thickness of guiding layer; on the contrary, the temperature properties of metal film hardly contribute to the influence of temperature on the reflectivity. Based on the analysis, the sensitivities of SMCOW with guiding layer made up of different optical glasses are computed under both spectral and angular interrogation. This letter is supposed to provide direction in designing SMCOW sensors against the temperature variation.

Since electrowetting has been proposed, researchers began to apply eletrowetting into different fields, such as lab-on-chip systems, display technologies, printings and optics etc. This paper mainly introduced structure, theory and application of optical devices based on electrowetting. The optical devices include liquid optical prism, liquid optical lens and display. The paper introduced their principle, specific application and many advantages in optical applications. When they are applied to optical system, production and experiment, they can reduce mechanical moving parts, simplify the structure, operate easily, decrease manufacturing cost and energy consumption, improve working efficiency, and so on. We learn and research them in detail that will contribute to research and develop optical eletrowetting in the future.

The inverse Doppler effect in photonic crystal with negative refractive index had been proofed experimentally in our previous research. In this paper, we studied the spatial harmonics of Bloch wave propagating in such PhCs by FFT method. The lagging and front phase evolutions reveal that both backward wave and forward wave exist in these harmonics. Subsequently, we studied the double Doppler effect phenomenon that both the normal and inverse Doppler exist in one photonic crystal simultaneously by using the improved dynamic FDTD method which we made it suitable for dealing with moving objects. The simulative Doppler frequency shifts were consistent with the theoretical values. Our study provides a potential technology in measurement area.

Optical heterodyne interfering is used to measure the Doppler shift of diffraction beam of moving plane grating. By introducing Doppler shift in reference beam and contrasting the final beat frequency, the Doppler shift is measured to be normal when incident light and diffraction light are in the same side of the normal of periodic plane grating, which shows that abnormal Doppler shift can not occur on the material with “negative refraction phenomenon” caused by periodicity. Periodic two-dimensional photonic crystal with the property of abnormal Doppler shift has equivalent negative refractive index, and the abnormal properties of left-handed materials are not only caused by periodicity.

Based on the partially coherent optical theory, an integral phase contrast modulation transfer function model is established for X-ray phase contrast imaging system, the model can be used to study the impact of X-ray source size on the X-ray phase contrast imaging system. Then, with the help of simulation and calculation, we give a comprehensive analysis about the influence of the X-ray source size on the overall phase contrast imaging system, Finally, The experimental results are given out to demonstrate its application.

The focusing properties of radially polarized hollow Gaussian beam (HGB) with on-axis spiral optical vortex are investigated theoretically by vector diffraction theory. The phase wavefront of HGB is the function of radial coordinate. Calculation results show that the focusing properties can be altered considerably by beam order of HGB, topological charge of the on-axis optical vortex, and phase parameter that characterizes the radial phase wavefront distribution. Higher topological charge induces focal evolution from one focal spot to annular focal pattern in transverse direction, while phase parameter can lead to focal shift along optical axis remarkably. In addition, focal shift direction can also be adjusted by changing varying direction of phase parameter.

Cylindrical vector beams have attracted much attention recently due to novel properties and applications. And generation for this kind of beams is very important and necessary when it is used in practice. In this article, a simple and convenient generation method for tunable cylindrical vector ring beams is proposed. Incident beam passes orderly through the convex axicon reflector, cylindrical polarization component, concave axicon reflector, and two half wave plates. These components are put coaxially and symmetrically. The cylindrical polarization component is a cylindrical sheet of polarizing film that is inserted between the convex axicon reflector and concave axicon reflector, which can initially convert beam into cylindrical vector ring beam. In addition, the two half wave plates are used to alter the polarization distribution symmetrically. Experimental results show that this kind of generation method is valid, feasible, and convenient.

Although the inverse Doppler effect has been observed experimentally at optical frequencies in photonic crystal with negative effective refractive index, its explanation is based on phenomenological theory rather than a strict theory. Elucidating the physical mechanism underlying the inverse Doppler shift is necessary. In this article, the primary electrical field component in the photonic crystal that leads to negative refraction was extracted and the phase evolution of the entire process when light travels through a moving photonic crystal was investigated using static and dynamic finite different time domain methods. The analysis demonstrates the validity of the use of np (the effective refractive index of the photonic crystal in the light path) in these calculations and reveals the origin of the inverse Doppler effect in photonic crystals.

A novel means of focal length measurement is proposed based upon Hartmann–Shack principle of wavefront detection. Mathematical approaches of focal length measurement are deduced without the necessity of knowing the position of lens principle plane. In experiment, laser sources with wavelength of 633 nm and 780 nm are separately used and focal length of three pieces of doublets is measured under two wavelengths mentioned above. As were shown by the results, this method of focal length measurement could not only accurately measure lens focal length, but also evaluate chromatic aberration of them. Since the intensity of light is detected by CCD, optical characteristics of lens beyond the range of visible light are also measurable when response range of CCD allows. This new means of focal length measurement is characterized by high accuracy, fast measuring and easy to setup, thereby, it is applicable in wide fields of area.

The human eye is an imperfect refractive system which not only has defocus and astigmatism, but also has spherical aberration, coma and anomalistic high-order aberrations, all of which have certain influence on the imaging quality of retina. What's worse, aberration is further enlarged as a result of mydriasis in dark field and weak light, thus making the vision performance of human eyes far below diffraction limitation. Further research revealed that human eye visual imaging is not only connected with refractive system, but also is closely related to the subjective judgment of human brain and the process of neural system. In order to overcome the deficiencies, wave-front aberration measurement method and system that has subjective visual compensation is proposed and conducted in combination with objective measurement, which ensures more accurate and realistic measuring results. The experimental data revealed that wave-front aberration obtained from subjective visual compensation measuring method is smaller than objective measurement, which is the result of subjects’ adaptive correction when watching sighting targets. In addition, when subjects are watching different sighting targets, the fluctuation value of wavefront aberration is small. Therefore, it is concluded that subjective visual compensation measuring method contributes to aberration measuring improvement and obtains results match with the realistic state by taking into consideration the actual condition of human eyes when watching targets. Hopefully, these discoveries will be of positive and beneficial value to the determination of human eye aberration treatment.

Experimental investigation of the reverse-Doppler shift of electromagnetic waves has previously been restricted to the microwave regime. Here, direct confirmation of the Doppler effect is reported at the infrared wavelength of 10.6 µm using a moving photonic crystal exhibiting a negative refractive index.

The absorption contrast image is very low for those weakly absorbing materials or weak phase object, such as the soft biological tissues, however, the phase item value of refractive index is a thousand larger than the absorption item, therefore the refractive index interferometry method is expected to be a new imaging tool for them. An interferometry method based on the X-ray crystallography is explored to the measurement of refractive index in this paper. The theoretical foundation, the optical design, the crystal transistor performance are the key parts to this interferometry method based on the X-ray crystallography. We give out a special refractive index detection scheme, using a laboratory hard X-ray source, and four single Si crystals. With this instrument, refractive index profile of those weak phase object can be unfolded accurately using this method. This refractive index interferometry method based on the X-ray crystallography will provide a new research tool for those special material properties or biological tissues study.

We propose a reformative Expectation-Maximization algorithm for brain MRI segmentation. The method extends the traditional EM method to a power transformed version. To test the algorithm we compare it with the method used in SPM software. The test results show that the method performs well in brain MR images segmentation, the brain MR images can be segmented into distinct tissue types.

Heating a benzene solution of the isomerized product of spiro[4.4]nona-1,3-diene(dicarbonyl)[ethoxy(aryl)carbene]iron phosphine adduct [(η 3 -C 9 H 12 )Fe{C(OC 2 H 5 )(C 6 H 4 CH 3 - o )}(CO) 2 PPh 3 ] ( 1 ) in a sealed quartz tube at 85–90 °C for 72 h gave the ring-opened η 4 olefin-coordinated dicarbonyliron phosphine complex [Fe{η 4 -C 5 H 7 CH CHCH 2 CH C(OC 2 H 5 )C 6 H 4 CH 3 - o }(CO) 2 PPh 3 ] ( 3 ) and cyclobutane derivative [C 24 H 22 O 7 ] ( 4 ). The thermal decomposition of analogous isomerized product [(η 3 -C 9 H 12 )Fe{C(OC 2 H 5 )(C 6 H 4 CH 3 - p )}-(CO) 2 PPh 3 ] ( 2 ) afforded the corresponding η 4 olefin-coordinated dicarbonyliron phosphine complex [Fe{η 4 -C 5 H 7 CH CHCH 2 CH C(OC 2 H 5 )C 6 H 4 CH 3 - p }(CO) 2 PPh 3 ] ( 6 ) and compound 4 . The structures of products 3 and 4 have been established by X-ray diffraction studies.

Heating a benzene solution of the COT-coordinated diiron bridging alkoxycarbene complexes [Fe2{μ-C(OC2H5)Ar}(CO)4(η8-C8H8)] (1, Ar = C6H5; 2, Ar = p-CH3C6H4; 3, Ar = p-CF3C6H4) in a sealed tube at ...

The temperature-dependent reflection spectrums of ultrahigh order guided modes of symmetrical metal-cladding waveguide (SMCW) are measured in angular interrogation. The results show that the reflection spectrum is characterized by extremely narrow resonance dip, which agrees well with numerical calculation. Based on the falling or rising edge of resonance dip of ultrahigh order guided modes of SMCW, a temperature sensor with characteristic of high sensitivity is proposed. Meanwhile, by experimentally determine the linear character between the shift of resonance angle and the variation of temperature, a method of angle compensation is put forward to extend the sensing range. Owing to its characteristics of high sensitivity, low cost and easy fabrication, the temperature sensor based on SMCW will be a promising sensor in many fields.

Progressive addition lens (PAL) is designed for those who suffer from myopia and presbyopia to have a clear vision from a far distance to a nearby distance. Additionally there are many people that also suffer from astigmatism and need to be corrected. The cylinder power can’t be simply added to the diopter of the PAL directly, because the diopter of the PAL needs to be changed smoothly. A methods has been proposed in this article to solve the problem, the freeform surface height of a PAL without astigmatism and the cylindrical lens surface height for the correction of astigmatism are calculated separately. The both two surface heights were added together, then the final surface is produced and shown with the both properties of PALs and cylindrical lenses used to correct the astigmatism.

The analysis of the temperature property of sensors based on symmetrical metal-cladding optical waveguide (SMCOW) is focused on analyzing the temperature property of reflectivity of SMCOW sensors, which is theoretically studied with single-factor investigation under spectral and angular interrogation scheme. There are mainly four factors influencing the temperature dependence of reflectivity, it is the temperature dependence of refractive index and thickness of guiding layer, along with the temperature dependence of the metal film thickness and metal-dielectric function. The simulation result shows that the effect of temperature on the reflectivity of SMCOW is mainly attributed to the temperature dependence of refractive index and thickness of guiding layeron the contrary, the temperature properties of metal film hardly contributes to the influence of temperature on the reflectivity. Based on the analysis, the sensitivities of SMCOW with guiding layer of different optical glasses are computed under both spectral and angular interrogation. This paper is supposed to provide direction in designing temperature-sensitive SMCOW structure sensors.

Compound [Fe2(μ-CO)2(CO)2(η5-C9H7)2] (1) reacts with aryllithium reagents, ArLi (Ar = C6H5, p-CH3C6H4, p-CF3C6H4) followed by alkylation with Et3OBF4 to give the diindenyl-coordinated diiron bridging alkoxycarbene complexes [Fe2{μ-C(OC2H5)Ar}(μ-CO)(CO)2(η5-C9H7)2] (2, Ar = C6H5; 3, Ar = p-CH3C6H4, 4, Ar = p-CF3C6H4). Complex 4 reacts with HBF4 · Et2O at low temperature to yield cationic bridging carbyne complex [Fe2(μ-CC6H4CF3-p)(μ-CO)(CO)2(η5-C9H7)2]BF4 (5). Cationic 5 reacts with NaBH4 in THF at low temperature to afford diiron bridging arylcarbene complex [Fe2{μ-C(H)C6H4CF3-p}(μ-CO)(CO)2(η5-C9H7)2] (6). The reaction of 5 with NaSC6H4CH3-p under the similar conditions gave the bridging arylthiocarbene complex [Fe2{μ-C(C6H4CF3-p)SC6H4CH3-p}(μ-CO)(CO)2(η5-C9H7)2] (7). Complex 5 can also react with carbonylmetal anionic compounds Na[M(CO)5(CN)] (M = Cr, Mo, W) to produce the diiron bridging aryl(penta-carbonylcyanometal)carbene complexes [Fe2{μ-C(C6H4CF3-p)NCM(CO)5}(μ-CO)(CO)2(η5-C9H7)2] (8, M = Cr; 9, M = Mo; 10, M = W). The structures of complexes 4, 6, 7, and 10 have been established by X-ray diffraction studies.