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We present a novel periodic sub-wavelength metallic grating with parabolic walls fabricated on the silica substrate. With finite difference time domain (FDTD) simulation, we find that the grating not only can realize broadband transmission in the visible range with TM-polarized incidence, but also can achieve higher transmission efficiency with TE-polarized light incidence. The transmission properties of the proposed grating strongly depend on the geometric parameters including the period, the thickness, the entrance width, and the exit width. The transmission spectra can be manipulated by tuning the parameters of the parabolic-wall grating. Transmission line theorem and the interaction between the surface plasmon waves on the slit walls are introduced to explain broadband extraordinary optical transmission of the grating proposed in this paper.

Foreign matter is easily mixed into cotton during picking, storing, drying, transporting, purchasing, and processing. These contaminants are difficult to remove in the spinning process and can cause yarn breakage, thus reducing efficiency of working. This paper proposed the new method based on machine vision to measure the contaminants in raw cottons. The color images of cottons with contaminants are acquired and divided three channels images. Intensity of illumination of cottons often is unstable because of the driving voltage of light source unsteady. The intensity of illumination of images should be corrected for measuring correction and precision. The Gamma adjustment function was adopted to correct non-uniform illumination for images. Through the experimental contrast, Gamma correction parameter is set as 0.8. The Otsu method is used to segment the image. After images of three channels’ information fusing, the contaminants of cotton samples can be correctly detected and cotton seeds also can be effectively inspected. The false detection ratio of the measuring system is less than 5%. The experimental results show the measuring system can meet with the requirement of the cotton's industry application.

Due to its atomically ultrathin morphology and superior optoelectronic properties, graphene has been broadly studied and utilized in phototransistors, photoconductors, or heterojunction nanostructures. However, in practical devices, the disadvantages of graphene should be concerned for its high dark current, very low on/off ratio, and high-priced fabrication cost. We report the photodetecting of the graphene/insulator/silicon heterojunction. The insulator layer is optimized to achieve balanced optoelectronic properties in terms of an Iph/Idark ratio of 4.17 × 103, a responsivity of 35 mA W−1, and a detectivity of 6.39 × 1010 Jones at a wavelength of 658 nm, with low operating voltage and static power dissipation (0.84 nW). Besides, response speed and degradation in the environment are tested. The mechanisms are revealed and analyzed by I-V measurements.

The semiconductor laser is the important part in the semiconductor laser frequency standard. The quality of light frequency standard depends on line width and stability of laser. Semiconductor laser is very sensitive to environmental changes, such as the temperature, humidity and so on. The driving voltage and circuit and the temperature compensation are significant to laser output stability. The paper put forward a novel method to drive the semiconductor laser based on constant voltage source. The experimental results show that the circuit is simple, reliable, and high-precision. After improvement, the driving source of laser can promise parameters: constant-current range is from 0 to 250 mA, and the drift of current is less than 10 −6 , and stability is 10 −5 . The drift of frequency of laser drive with the circuit is within 10 −5 nm.

Improved field emission properties are demonstrated based on the multidimensional graphene-carbon nanotube (G-CNT) emitters decorated with gold nanoparticles (AuNPs). Chemical vapor deposition and screen printing are adopted to prepare the complex structures of G-CNT emitters. The AuNPs decoration of the emitters is implemented by the thermal evaporation and rapid thermal annealing of the Au film. Experimental results reveal that the proposed field emitters can supply a peak current of >17 mA with the current density of 556.05 mA/cm $^{2}$ . G-CNTs retain the turn-ON electric field that is $\mu \text{m}$ , and the emission has been proved to be very stable.

The Erbutu Ni-Cu sulfide deposit is hosted in a small ultramafic intrusion located at the southern margin of the Central Asian orogenic belt, Inner Mongolia. This deposit is the first case of a magmatic sulfide deposit related to boninitic magmatism in an arc setting. The host intrusion is composed of orthopyroxenite and olivine orthopyroxenite. More than three quarters of the intrusion contains economic, disseminated sulfide mineralization. SHRIMP U-Pb dating of zircons from the intrusion gives a crystallization age of 294.2 ± 2.7 Ma, similar to the age of the Permian Tarim plume in northwest China. Olivine orthopyroxenite is characterized by olivine crystals with relatively high Fo contents (85–88 mol %) and extremely low Ca contents (

Freestanding and transferable silica nanosheets with thicknesses of ≈5-7 nm are prepared via ethyl acetate-mediated hydrolysis of silica precursors in aqueous solution. The resulting silica nanosheets have shown many potential applications. For example, they can be used as the support film on the finer mesh grids for transmission electron microscopy imaging and as the precursor for the synthesis of silicon nanosheets.

OBJECTIVE: Prevention of influenza among infants and young children is a public health priority because of their high risk for influenza-related complications. Depending on a child’s age and previous influenza vaccination history, they are recommended to receive either 1 dose or 2 doses of influenza vaccine to be considered fully vaccinated against influenza for the season. We compared estimates of full (complete) influenza vaccination coverage of children 6 to 23 months across 10 consecutive influenza seasons (2002–2012), by race/ethnicity, age group, and by number of doses required to be fully vaccinated given child’s vaccination history. METHODS: National Immunization Survey data were used to estimate full influenza vaccination status among children 6 to 23 months on the basis of provider report. Estimates were computed by using Kaplan-Meier survival analysis methods. RESULTS: Full influenza vaccination coverage among children 6 to 23 months increased from 4.8% in the 2002–2003 influenza season to 44.7% in the 2011–2012 season. In all 10 influenza seasons studied, non-Hispanic black children and Hispanic children had lower full influenza vaccination coverage than non-Hispanic white children. For all 10 influenza seasons, full influenza vaccination coverage was higher among children requiring only 1 dose compared with those requiring 2 doses. CONCLUSIONS: Less than half of children 6 to 23 months in the United States, and an even a smaller percentage of Hispanic and non-Hispanic black children, are fully vaccinated against influenza. More implementation of evidence-based strategies that increase the percentage of children who are fully vaccinated is needed.

A novel roll measurement method based on a rectangular-prism is presented. A collimated beam is normally incident upon a rectangular-prism with splitting film, and it is divided into two parts, the reflected and the transmitted beams. The displacements of the reflected and the transmitted beams are measured by two quadrant photoelectric detectors QD1 and QD2, respectively. The displacement change in the y-axis caused by roll can be measured with differential measurements from two quadrant photoelectric detectors. Theoretic analyses show that the crosstalk of straightness errors and yaw errors are avoided, and the crosstalk of the pitch α can be neglected by adopting differential measurements because the direction changes of the reflected and the transmitted beams are both double the changes of pitch. In this way, the stability for the roll measurement can be greatly enhanced. The systemic model is established and the feasibility of such a system is verified by theoretical analysis and experiments. The resolution of 0.3″ and measurement accuracy of 2″ can be obtained by the set-up measurement system.

Objective To identify the stability of socio-environmental, behavioral, and health predictors of mortality over an eight year time frame. Study Design Cohort study. Setting Data were analyzed at a large medical university in the Southeast United States of America (USA). Methods Adults with residual impairment from a spinal cord injury (SCI) who were at least one year post-injury at assessment were recruited through a large specialty hospital in the Southeast USA. 1209 participants were included in the final analysis. A piecewise exponential model with 2 equal time intervals (eight years total) was used to assess the stability of the hazard and the predictors over time. Results The hazard did significantly change over time, where the hazard in the first time interval was significantly lower than the second. There were no interactions between the socio-environmental, behavior, or health factors and time, although there was a significant interaction between age at injury (a demographic variable) and time. Conclusion These results suggest there is stability in the association between the predictors and mortality, even over an eight year time period. Results reinforce the use of historic variables for prediction of mortality in persons with SCI.

Summary Background and objectives African Americans (AAs) have four times higher prevalence of ESRD than Caucasians. Therefore, long-term effects of kidney donation are of considerable importance in this patient population. Design, setting, participants, & measurements GFR was measured by 125 I-iothalamate clearance, 24-hour urine albumin excretion, and 24-hour BP monitoring in 33 AAs and 11 CAs who donated kidneys for transplantation 5 to 23 years previously. Results Mean GFRs were 76 13 and 78 11 ml/min per 1.73 m 2 for AA and CA donors, respectively. Nine percent of the AA donors and none of the CA donors had GFRs below 60 ml/min per 1.73 m 2 .A A donors had a tendency for lower prevalence of microalbuminuria compared with CA donors (18.1% versus 36.3%) and a tendency for higher prevalence of macroalbuminuria compared with CAs (12.1% versus 0.0%). Twenty-four percent of the AAs, and 45% of the CAs were hypertensive with mean daytime BP 135/85 mmHg. Only 6% of AAs had a decrease in mean nocturnal systolic BP of 10% or more as compared with daytime readings. Older age at time of donation was associated (P 0.046) with lower GFR values compared with younger ages. Conclusion Carefully selected AA kidney donors have well preserved renal function and a low prevalence of hypertension many years after kidney donation. Abnormal albumin excretion and loss of physiologic decrease in nocturnal BP is more prevalent in AA donors than the general AA population. Older age at donation may predict lower GFR after donation. Clin J Am Soc Nephrol 6: 1474–1480, 2011. doi: 10.2215/CJN.08240910

Krause JS, Zhai Y, Saunders LL, Carter RE. Risk of mortality after spinal cord injury: an 8-year prospective study. Objective To evaluate a theoretical model for mortality after spinal cord injury (SCI) by sequentially analyzing 4 sets of risk factors in relation to mortality (ie, adding 1 set of factors to the regression equation at a time). Design Prospective cohort study of data collected in late 1997 and early 1998 with mortality status ascertained in December 2005. We evaluated the significance of 4 successive sets of predictors (biographic and injury, psychologic and environmental, behavioral, health and secondary conditions) using Cox proportional hazards modeling and built a full model based on the optimal predictors. Setting A specialty hospital. Participants Adults (N=1386) with traumatic SCI, at least 1 year postinjury, participated. There were 224 deaths. After eliminating cases with missing data, there were 1209 participants, with 179 deceased at follow-up. Interventions Not applicable. Main Outcome Measures Mortality status was determined using the National Death Index and the Social Security Death Index. Results The final model included 1 environmental variable (poverty), 2 behavioral factors (prescription medication use, binge drinking), and 4 health factors or secondary conditions (hospitalizations, fractures/amputations, surgeries for pressure ulcers, probable major depression). Conclusions The results supported the major premise of the theoretical model that risk factors are more important the more proximal they are in a theoretical chain of events leading to mortality. According to this model, mortality results from declining health, precipitated by high-risk behaviors. These findings may be used to target those who are at high risk for early mortality as well as to direct interventions to the particular risk factor.

A novel method for laser beam straightness error measurements based on common-path compensation is proposed. The basic principle of the method is described and the math-model is established. Furthermore, the influence of laser beam drift on straightness error measurements is analyzed. The experimental results show that the measurement accuracy can be greatly improved by using the common-path compensation for laser beam drift.

Krause JS, Carter R, Zhai Y, Reed K. Psychologic factors and risk of mortality after spinal cord injury. Objective To identify the association of 2 distinct psychologic constructs, personality and purpose in life (PIL), with risk of early mortality among persons with spinal cord injury (SCI). Design Prospective cohort study with health data collected in late 1997 and early 1998 and mortality status ascertained in December 2005. Setting A large rehabilitation hospital in the southeastern United States. Participants Adults (N=1386) with traumatic SCI, at least 1 year postinjury. Interventions Not applicable. Main Outcome Measures We first evaluated the significance of a single psychologic predictor (a total of 6 scales) while controlling for biographic and injury predictors using Cox proportional hazards modeling and subsequently built a comprehensive model based on an optimal group of psychologic variables. Results There were a total of 224 (16.2%) observed deaths in the full sample. The total number of deaths was reduced to 164 in the final statistical model (of 1128 participants) because of missing data. All 6 psychologic factors were statistically significant in the model that was adjusted for biographic and injury factors, whereas only 3 psychologic factors were retained in the final comprehensive model, including 2 personality scales (Impulsive Sensation Seeking, Neuroticism-Anxiety) and the PIL scale. The final comprehensive model only modestly improved the overall prediction of survival compared with the model with only biographic and injury variables, because the pseudo- R 2 increased from 0.121 to 0.129, and the concordance increased from 0.730 to 0.747. Conclusions The results affirm the importance of psychologic factors in relation to survival after SCI.

To directly compare estimates of potential depressive disorders and clinically significant depressive symptoms using the Patient Health Questionnaire-9 (PHQ-9) and Older Adult Health and Mood Questionnaire (OAHMQ) among participants with spinal cord injury (SCI).727 participants from a hospital in the Southeastern United States were administered the PHQ-9 and OAHMQ during a follow-up survey. We compared the rates of depressive disorders using cutoff scores and diagnostic criteria for each instrument. No independent psychiatric diagnostic interviews were conducted.The PHQ-9 and OAHMQ were significantly correlated (r = .78), and both were correlated with satisfaction with life (r = -.48, -.54). Using recommended diagnostic scoring procedures, 10.7% of participants met the diagnostic criteria for major depressive disorder with the PHQ-9; 9.3% met the criteria for major depression based on PHQ-9or = 10; and 19.7% based on PHQ-9or = 15. Using the OAHMQ, 19.7% reported probable major depression and 44.5% clinically significant symptomatology.The measures were highly correlated overall. However, the estimated prevalence of depressive disorders varied substantially between the 2 instruments. These estimates were comparable to those previously reported for each instrument (i.e., higher rates with the OAHMQ). Therefore, differing estimates of depressive disorders reported in the literature using these instruments were largely attributable to the instruments themselves.

Suspended graphene (SG) membranes could enable strain-engineering of ballistic Dirac fermion transport and eliminate the extrinsic bulk disorder by annealing. When freely suspended without contact to any substrates, graphene could be considered as the ultimate two-dimensional (2D) morphology, leading to special field characteristics with the 2D geometrical effect and effectively utilized as an outstanding structure to explore the fundamental electronic or optoelectronic mechanism. In this paper, we report field emission characterization on an individual suspended few-layer graphene. A controllable wet transfer method is used to obtain the continuous and suspended graphene membrane on interdigitated gold electrodes. This suspended structure displays an overall field emission from the entirely surface, except for the variation in the emitting positions, acquiring a better enhancement than the exfoliated graphene on the conventional flat substrate. We also observe the transition process from space charge flow at low bias to the Fowler-Nordheim theory at high current emission regime. It could enable theoretical and experimental investigation of the typical electron emission properties of the 2D regime. Numerical simulations are also carried out to study the electrical properties of the suspended structure. Further improvement on the fabrication would realize low disorder, high quality, and large-scale suspended graphene devices.

This paper reports the fabrication of bulk molybdenum field emitter arrays with integrated, self-aligned gates. Based on molybdenum deep reactive ion etching, the fabrication process is significantly simplified compared with that of conventional Spindt-type arrays. In the present structures, the distance between the gate and emitter has been precisely controlled by the thickness of SiO2 dielectric layer. In this work, current densities of 84mA/cm2 were produced from a uniform array of 2500 tips covering a total emission area of just 1 mm2, driven at gate-emitter voltages of just 120 V. Compared to diode-type emitters we reported elsewhere [1], the emission current densities increased by 240 times to 33.6nA/tip, owing to the extractor gates. Further scaling down of the pitch to may lead to an increase of the current densities to several A/cm2, which is very promising for high-current cathode applications such as X-ray sources.

Metabolites of estrogen (estrone-3-glucuronide [E1G]) and melatonin (6-hydroxymelatonin sulfate [6-OHMS]) were characterized among women living in a community with increased radiofrequency (RF) exposure from radio and television transmitters.RF spot measurements, and personal 60-Hz magnetic field and residential parameters were collected. Overnight urine samples were assayed for E1G and 6-OHMS excretion.Among premenopausal women, there were no associations between RF or 60-Hz nonionizing radiation and E1G or 6-OHMS excretion. Among postmenopausal women, increased residential RF exposures, transmitter proximity and visibility, and temporally stable 60-Hz exposures were significantly associated with increased E1G excretion. This association was strongest among postmenopausal women with low overnight 6-OHMS levels.RF and temporally stable 60-Hz exposures were associated with increased E1G excretion among postmenopausal women. Women with reduced nocturnal 6-OHMS excretion may represent a sensitive subgroup.

The Sawaya'erdun gold deposit in the western segment of the South Tianshan, Xinjiang, China, is a large, low-grade orogenic gold deposit. An abundance of index fossils in the ore-hosting strata, including brachiopoda, corals and Schwagerina, show that the fossil age of the country rocks ranges from Late Carboniferous to Early Permian. Whole rock Rb–Sr and Sm–Nd isochron ages, ranging from 292.43±0.38 to 304.7±11.6 Ma, are concordant with a Late Carboniferous age. Gold mineralization is strictly controlled by a fault zone. Ore minerals are dominated by sulfides, with gold inhomogeneously distributed within them; gangue minerals are quartz, siderite or calcite. Data suggest that the ore-forming fluid was derived predominantly from an active meteoric groundwater system. Ore-forming temperatures are estimated to have been within the range 110 to 220 °C. New 40 Ar/ 39 Ar isotope age determinations of auriferous quartz are in excellent agreement with Rb–Sr ages obtained from fluid inclusions in quartz. They suggest gold mineralization at 206 to 213 Ma (Late Indosinian). Such an age is consistent with the age of formation given for other gold deposits in the region, such as Bulong and Dashankou. Combined with K–Ar geochronological data and observed geological features, it is concluded that the Indosinian metallogentic epoch represents a previously unrecognized, major period of gold metallogeny in the southwestern Chinese Tianshan. In some ways, the Sawaya'erdun gold deposit can be compared with the Muruntau gold deposit in Uzbekistan with respect to geological setting, host lithology, mineralization style, mineral assemblages, geochemical association and metallogenic processes involved. Despite this, the Sawaya'erdun gold deposit possesses a number of characteristics typical of only low-temperature metallogenesis. © 2007 Elsevier B.V. All rights reserved.

The triangulation measurement is a kind of active vision measurement. The laser triangulation displacement is widely used with advantages of non-contact, high precision, high sensitivity. The measuring error will increase with the nonlinear and noise disturbance when sensors work in large distance. The paper introduces the principle of laser triangulation measurement and analyzes the measuring error and establishes the compensation error. Spot centroid is extracted with digital image processing technology to increase noise-signal ratio. Results of simulation and experiment show the method can meet requirement of large distance and high precision.

Laser collimation technology is widely applied in the positioning and measurement. The accuracy is affected by the laser beam drift, so laser beam drift compensation is necessary. Effective compensation depends on the characteristics analysis of laser beam drifts. Spectrums and values of noise signals caused by electronic noise, laser source, and environment, are analyzed in detail. The characteristics of various types of noise signals are gained and the effectiveness of low-pass filter and mean process are verified and compared. This study will provide support for separation of various types of signals and compensation of beam drifts.

Background Studies are published on settings adults receive influenza vaccination but few have reported on settings children are vaccinated and how this might be changing over time or vary by socio-demographics. Methods Data from the National Immunization Survey-Flu were analyzed to assess place of influenza vaccination among vaccinated children 6 months–17 years during the 2010–11, 2011–12, 2012–13, and 2013–14 influenza seasons. The percentage of children vaccinated at each place was calculated overall and by age, race/ethnicity, income, and Metropolitan Statistical Area (MSA). Results The places children received influenza vaccination varied little over four recent influenza seasons. From the 2010–11 through 2013–14 influenza seasons the percentage of vaccinated children receiving influenza vaccination at a doctor's office was 64.1%, 65.1%, 65.3%, and 65.3%, respectively with no differences from one season to the next. Likewise, for vaccination at clinics or health centers (17.8%, 17.5%, 17.0%. 18.0%), health departments (3.2%, 3.6%, 3.0%, 2.8%), and other non-medical places (1.6%, 1.4%, 1.2%, 1.1%), there were no differences from one season to the next. There were some differences for vaccinations at hospitals, pharmacies, and schools. There was considerable variability in the place of influenza vaccination by age, race/ethnicity, income, and MSA. Fewer Hispanic children were vaccinated at a doctor's office than black, white, and other or multiple race children and fewer black children and children of other or multiple races were vaccinated at a doctor's office than white children. More children at or below the poverty level were vaccinated at a clinic or health center than all of the other income groups. Conclusion Most vaccinated children receive their influenza vaccination at a doctor's office. Place of vaccination changed little over four recent influenza seasons. Large variability in place of vaccination exists by age, race/ethnicity, income, and MSA. Monitoring place of vaccination can help shape future immunization programs.

Influenza vaccines available for children in the United States include inactivated influenza vaccine (IIV) and live, attenuated influenza vaccine (LAIV). Objectives of this study were to quantify proportions of IIV and LAIV received by vaccinated children, and examine associations between vaccine type received and demographic characteristics.National Immunization Survey-Flu (NIS-Flu) parental reported data for the 2011-12 through 2013-14 influenza seasons were used to estimate proportions of vaccinated children 2-17 years who received IIV and LAIV. Tests of association between vaccination type and demographic variables were conducted using Wald chi-square tests and pair-wise comparison t-tests. Multivariable logistic regression was used to determine variables independently associated with receipt of LAIV versus IIV.In the 2013-14 season, 33.3% of vaccinated children received LAIV, similar to the proportion in the 2011-12 (32.2%) and 2012-13 (32.1%) seasons. Across all seasons studied, the strongest observed association was between vaccination type and child's age, with children 2-8 years (Adjusted Prevalence Ratio (95% confidence interval) [APR(95% CI)] 1.41(1.27-1.56), 1.46(1.34-1.59), and 1.50(1.38-1.63) for 2011-12, 2012-13, and 2013-14) and 9-12 years (APR(95% CI) 1.37(1.23-1.54), 1.38(1.26-1.51), and 1.50(1.38-1.63) for 2011-12, 2012-13, and 2013-14) being more likely to have received LAIV than children 13-17 years. Among those vaccinated, whites were more likely to have received LAIV compared with blacks (APR(95% CI) 1.19(1.05-1.35), 1.24(1.10-1.39), and 1.22(1.11-1.34) for 2011-12, 2012-13, and 2013-14), and children living above poverty (annual income$75,000) were more likely to have received LAIV than those living at or below poverty (APR(95% CI) 1.43(1.23-1.67), 1.13(1.02-1.26), and 1.16(1.06-1.28) for 2011-12, 2012-13, and 2013-14).This study provides a baseline of the extent and patterns of LAIV uptake that can be used to measure the impact of relevant public health policy. Additional research is needed to investigate parental and provider preferences and barriers regarding LAIV.

There are large to superlarge magnesite and talc deposits occurring in Mg-rich carbonate formations distributed in the early Proterozoic Dashiqiao Formation in eastern Liaoning Province, China. The discovery of the sedimentary gypsum, isotopic geochemistry of δ18Osmow, δ13CPDB, δ34SVCDT and Sr/Ba ratio of carbonate, talc, quartz and gypsums with field investigation and sample analysis in laboratory demonstrate that the formation of magnesite and talc deposits is closely related to marine evaporates, which then underwent reworking of regional metamorphism and hydrothermal metasomatism. Metasomatic fluids originating from the paleoseawater played a controlling role in the formation of talc deposits.

The Dongping area in the central part of the northern marginal zone of the North China Craton (NCC) is one of the most important gold-producing areas in China, and has been intruded by a number of alkaline and granitic batholiths or plutons spatially associated with gold deposits. Previous dates on these intrusions yield contradictory data, depending on the isotopic methodology used, and have led to ambiguity in understanding magmatic evolution and gold mineralization of the region. Detailed SHRIMP U–Pb zircon geochronology of the alkaline and granitic rocks in the study area now reveals details of its tectono-magmatic history. Zircons from a granitic gneiss hosting the Xiaoyingpan gold deposit yielded concordant ages of ca. 2.5 Ga. This constrains regional metamorphism of the Archaean basement to late Archaean time. A second magmatic event at ca. 1.8 Ga is revealed by xenocrystic/inherited zircons with this age. These two Precambrian events are coeval with those in other parts of the NCC. The largest igneous intrusion in the region, the Shuiquangou syenite–monzonite complex, was emplaced at ca. 390 Ma, as indicated by the magmatic zircon populations of the two samples from the central and eastern parts of the complex. The accretion of a volcanic arc onto the northern margin of the NCC is considered as a plausible cause of this alkaline magmatism. The emplacement of the Guzuizi porphyritic granite pluton at 236±2 Ma represents another major magmatic event in the region, probably a response to postcollisional orogeny following amalgamation of the North China and Angara cratons. Latest magmatism is marked by the emplacement of the Shangshuiquan monzogranite at 142.2±1.3 Ma, which is most likely related to an underplating event that took place in the Dongping and its adjacent areas at ca. 140 Ma. More importantly, these results suggest that gold mineralization in the area, essentially a single event as indicated by similar deposit characteristics, is broadly coeval with this latest granite magmatism. Hence, this mineralization is about 250 Ma later than the emplacement of the Shuiquangou alkaline complex and, thus, is interpreted to preclude the widely accepted model that suggests gold deposits have genetic relationships with alkaline magmatism. The late timing of gold mineralization with respect to felsic magmatism in the area is similar to those observed in other major gold-producing provinces in the NCC. In all these major gold provinces, we suggest that gold mineralization is coeval with the latest granite magmatic event at about 140–120 Ma. This farther suggests that these mesothermal gold deposits were formed from similar tectono-magmatic environments.

The heterojunction between metal and silicon (Si) is an attractive route to extend the response of Si-based photodiodes into the near-infrared (NIR) region, so-called Schottky barrier diodes. Photons absorbed into a metallic nanostructure excite the surface plasmon resonances (SPRs), which can be damped non-radiatively through the creation of hot electrons. Unfortunately, the quantum efficiency of hot electron detectors remains low due to low optical absorption and poor electron injection efficiency. In this study, we propose an efficient and low-cost plasmonic hot electron NIR photodetector based on a Au nanoparticle (Au NP)-decorated Si pyramid Schottky junction. The large-area and lithography-free photodetector is realized by using an anisotropic chemical wet etching and rapid thermal annealing (RTA) of a thin Au film. We experimentally demonstrate that these hot electron detectors have broad photoresponsivity spectra in the NIR region of 1200-1475 nm, with a low dark current on the order of 10-5 A cm-2. The observed responsivities enable these devices to be competitive with other reported Si-based NIR hot electron photodetectors using perfectly periodic nanostructures. The improved performance is attributed to the pyramid surface which can enhance light trapping and the localized electric field, and the nano-sized Au NPs which are beneficial for the tunneling of hot electrons. The simple and large-area preparation processes make them suitable for large-scale thermophotovoltaic cell and low-cost NIR detection applications.

The Eastern Yangtse Craton of central to eastern China is an important FeCu metallogenic province. Based on studies of the regional geology and tectonic evolution, this metallogenic belt is controlled by faults and aulacogens in the continental plate. In the Early Yanshan Epoch (Jurassic), the dominant west-northwest and east-west lithospheric faults controlled the distribution of Cu (Mo, and Au) mineralization, whereas in the Late Yanshan Epoch (Cretaceous) the north-northeast and northeast lithospheric faults controlled CuFe mineralization. In a mineral district, the distribution of ore-fields is under the dual control of basement fault(s) and near-surface fault(s). Based on the relation of ring and lineament faults to intrusions, a ‘three-level’ model of vertical zonation is proposed. Systematic petrochemical studies of Mesozoic igneous rocks and mineralization identify three subseries: (1) a calc-alkaline, intermediate to silicic subseries rich in potassium; (2) a calc-alkaline, intermediate to felsic subseries rich in sodium; and (3) a calc-alkaline, intermediate to mafic subseries rich in sodium. Genetic types of ore deposits are diverse, including Fe and Cu skarns, Cu porphyries, Fe ore magma injections, Ningwu-Luzong Fe deposits (from late orthomagmatic to pegmatitic-pneumato-hydrothermal, and to mesothermal-epithermal) associated with subvolcanic rocks, and remobilized sedimentary Fe and/or Cu deposits. The genetic types of ore deposits form two metallogenic series: (1) a sedimentary metallogenic series (active mainly in the Paleozoic), and (2) a magmatic-hydrothermal metallogenic series consisting of three subseries (active predominantly in the Jurassic and Cretaceous), with the latter being more important in this region. The superposition and compounding of these two metallogenic series contribute to many styles of mineralization in this mineral province.

Few large prospective studies have examined associations between nonsteroidal anti-inflammatory drug (NSAID) use and non-Hodgkin lymphoma (NHL). We examined the association between NSAID use and NHL incidence among 149,570 participants in the Cancer Prevention Study-II Nutrition cohort. Aspirin and nonaspirin NSAID use were reported at enrollment in 1992 and updated on periodic follow-up questionnaires. During follow-up through 2007, 1,709 incident NHLs were identified. Time-dependent hazard ratios were calculated using extended Cox regression. Compared to no use, current use of 60+ NSAID pills/month (aspirin and nonaspirin NSAIDs combined) was associated with slightly higher NHL incidence (hazard ratio [HR] = 1.26, 95% confidence interval [CI], 1.04–1.53), but no association with frequency of use was observed when NSAID exposure was lagged by approximately 2 years (HR = 1.08, 95% CI, 0.88–1.32). Long duration regular use (current use of 30+ pills/month for ≥5 years) was not associated with NHL incidence (HR = 1.09, 95% CI, 0.91–1.33). In subtype analyses, current use of 60+ NSAID pills/month was associated with follicular lymphoma incidence (HR = 1.87, 95% CI, 1.08–3.24). This association persisted when NSAID exposure was lagged (HR = 1.76, 95% CI, 1.04–2.98) and was similar for aspirin and nonaspirin NSAIDs. The association of current, but not lagged, NSAID use with risk of all NHL could be attributable to use of NSAIDs to relieve symptoms of undiagnosed NHL. However, the association with follicular lymphoma persisted in analyses where NSAID use was lagged and should be investigated further. These findings are particularly important for aspirin as the risks and benefits of prophylactic daily use are weighed. Cancer Epidemiol Biomarkers Prev; 22(3); 422–8. ©2013 AACR.

The radiative processes associated with quantum dots (QDs), fluorophores and other radiating systems can be profoundly modified by their interaction with plasmonic nanostructures. This interaction is associated with the localized electromagnetic field enhancement and the resonance absorption band. Extreme electromagnetic environments can be created in well-designed plasmonic nanostructures, such as metal film-dielectric layer-metal nanoparticles (NPs). Recently, so called film-coupled NPs have received a significant amount of attentions due to the strong surface plasmon resonances (SPRs). In this paper, we experimentally study the plasmon-enhanced energy transfer between CdSe/ZnS QDs and tunable film-coupled NPs. A facile route of seeding growth of self-assembled particles in situ is primarily presented for the large-area uniform fabrication of film-coupled NPs. The size-dependent energy transfer of Au NPs is demonstrated and the influence of the distribution of top Au NPs is described in detail. The experimental results demonstrate that the metallic nanostructures interact with the CdSe/ZnS QDs with obviously enhanced Forster resonance energy transfer (FRET) probability, and the fluorescence lifetime of QD materials is dramatically shortened. FRET is considered to be responsible for the PL quenching and the nonradiative decay acts as the dominant decay channel. The experimental results are also supported by finite-difference time-domain (FDTD) simulations which intend to collect design paths for the plasmon-enhanced energy transfer.

Background Shiftwork among health care workers impacts upon the safety and health of both employees and patients. Aims To characterize shiftwork-related attitudes, behaviours, symptoms and coping strategies among health care workers, two validated questionnaires (the Standard Shiftwork Index and the Pressure Management Indicator) were used to identify factors predicting shiftwork adaptation. Methods Participants (n = 376, response rate 25%) were grouped according to their work schedule (days, permanent evenings, rotating days plus evenings, permanent nights or relief and combined shifts). Indicators of lifestyle, work organization, sleep disruption, health and pressure management among workers on irregular shifts were compared with participants on day shifts, after adjustment for gender, age and marital status. Principal components analysis and ordinal logistic regression were used among irregular shiftworkers to identify factors predicting schedule adaptation. Results Night and relief/combined shiftworkers reported a greater ability to accommodate irregular schedules and disrupted sleep, but were also more likely to report work-related impacts than day workers. Permanent night workers generally reported poorer health, more absenteeism and less job satisfaction than day workers. Factors associated with optimal work performance or schedule contentment among shiftworkers included adequate sleep, evening circadian preference, increased age and organizational satisfaction. Reduced work performance or schedule discontent was associated with sleep/wake difficulties and poor health. Conclusions This study confirmed previous research and identified factors that can be targeted for the development of more effective shiftwork adaptation programmes in a health care setting (sleep timing and duration, exercise and optimal health and organizational satisfaction).

Ballistic electron transport in the nanogap devices will make it practical to combine the advantages of solid-state devices and vacuum electron devices including high integration and high frequency characteristics. Although a number of experiments have been exploited on frequency characteristic in nanogap, less modeling or calculations were investigated at such scale yet. In this paper, the concept of mean flight time is proposed in order to theoretically determine the frequency in nanoscale. Traditionally, we have to first determine the frequency response diagram and then deduce the cut-off frequency. This work presents a new method for exploring the frequency characteristics of electron transport in a nanogap structure by calculations and numerical simulations. A double-gate structure was applied in the simulations, and the results suggest that the nanogap structure can perform in the THz range. Additionally, an equivalent circuit model was adopted to demonstrate the validity of this method. Our results provide a model for the intrinsic ballistic transportation of electrons inside the nanogap electron devices.