SETTING: Current passive case finding strategies are not effective at identifying tuberculosis (TB) patients in rural China. OBJECTIVE: To evaluate a community-based, active case finding (ACF) scheme in identifying symptomatic individuals with TB. DESIGN: We conducted door-to-door household visits of all residents aged >/=15 years at two rural sites to screen for TB symptoms. Individuals with symptoms were enrolled and asked to provide three sputum samples. All participants underwent chest X-ray, and microbiologic detection of Mycobacterium tuberculosis from sputum samples using microscopy, solid culture and Xpert(R) MTB/RIF was performed. RESULTS: Among the 19 334 residents screened for TB symptoms, 865 (4.5%) reported having >/=1 symptom. A total of 52 TB cases were detected, 11 of whom had microbiologic confirmation. Xpert identified all five M. tuberculosis culture-positive cases and yielded an additional three diagnoses. Prevalence of newly detected TB at the two sites through ACF was respectively 475 and 196 per 100 000 population. These estimates are respectively four and eight times, on average, higher than those identified through passive surveillance during the previous 5-year period for the two sites. CONCLUSION: Community-based symptom screening followed by laboratory tests was found to be feasible and effective in increasing TB case finding in rural China.
Epidemiological studies have showed an association between black carbon (BC) exposure and adverse health effects. This study intends to investigate the influence of oxidation processes in atmosphere on the initial cellular responses of BC. The changes of gene expressions induced by fresh BC (FBC) and ozone oxidized BC (OBC) in human lung epithelial A549 cells were analyzed. And their toxic effects presented by viability, LDH release and DNA damage were compared. Totally 47, 000 genes in A549 cells were examined using Affymetrix Human U133 plus 2.0 chips. Some of the differentially expressed genes were verified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results showed that 1446 genes (including 756 up -regulated and 690 down -regulated) and 1594 genes (including 788 up-regulated" and 806 down -regulated genes) were significantly changed by FBC and OBC respectively. Only 4 of 14 (FBC)/15 (OBC) oxidative stress related genes,up-or down -regulated by FBC and OBC, were identical; 13 of 29 (FBC)/31 (OBC) inflammation related genes, and 6 of 20 (FBC)/18 (OBC) autophagy related genes were identical. No obvious differences were observed between the toxic effects of FBC and OBC. The cytotoxicity of OBC and FBC in A549 cells is at least partially induced by oxidative stress and consequent inflammation or autophagy process. Previous studies indicated that OBC may be more toxic than FBC. However, our results suggested that FBC and OBC might lead to diverse toxic endpoints through activating different molecular pathways. (C) 2017 Elsevier Ltd. All rights reserved.
Hydroxyl (OH) radical reactivity (k(OH)) has been measured for 18 years with different measurement techniques. In order to compare the performances of instruments deployed in the field, two campaigns were conducted performing experiments in the atmospheric simulation chamber SAPHIR at Forschungszentrum Julich in October 2015 and April 2016. Chemical conditions were chosen either to be representative of the atmosphere or to test potential limitations of instruments. All types of instruments that are currently used for atmospheric measurements were used in one of the two campaigns. The results of these campaigns demonstrate that OH reactivity can be accurately measured for a wide range of atmospherically relevant chemical conditions (e.g. water vapour, nitrogen oxides, various organic compounds) by all instruments. The precision of the measurements (limit of detection < 1 s(-1) at a time resolution of 30 s to a few minutes) is higher for instruments directly detecting hydroxyl radicals, whereas the indirect comparative reactivity method (CRM) has a higher limit of detection of 2 s(-1) at a time resolution of 10 to 15 min. The performances of the instruments were systematically tested by stepwise increasing, for example, the concentrations of carbon monoxide (CO), water vapour or nitric oxide (NO). In further experiments, mixtures of organic reactants were injected into the chamber to simulate urban and forested environments. Overall, the results show that the instruments are capable of measuring OH reactivity in the presence of CO, alkanes, alkenes and aromatic compounds. The transmission efficiency in Teflon inlet lines could have introduced systematic errors in measurements for low-volatile organic compounds in some instruments. CRM instruments exhibited a larger scatter in the data compared to the other instruments. The largest differences to reference measurements or to calculated reactivity were observed by CRM instruments in the presence of terpenes and oxygenated organic compounds (mixing ratio of OH reactants were up to 10 ppbv). In some of these experiments, only a small fraction of the reactivity is detected. The accuracy of CRM measurements is most likely limited by the corrections that need to be applied to account for known effects of, for example, deviations from pseudo first-order conditions, nitrogen oxides or water vapour on the measurement. Methods used to derive these corrections vary among the different CRM instruments. Measurements taken with a flow-tube instrument combined with the direct detection of OH by chemical ionisation mass spectrometry (CIMS) show limitations in cases of high reactivity and high NO concentrations but were accurate for low reactivity (< 15 s(-1)) and low NO (< 5 ppbv) conditions.
The broad applicability of super-resolution microscopy has been widely demonstrated in various areas and disciplines. The optimization and improvement of algorithms used in super-resolution microscopy are of great importance for achieving optimal quality of super-resolution imaging. In this review, we comprehensively discuss the computational methods in different types of super-resolution microscopy, including deconvolution microscopy, polarization-based super-resolution microscopy, structured illumination microscopy, image scanning microscopy, super-resolution optical fluctuation imaging microscopy, single-molecule localization microscopy, Bayesian super-resolution microscopy, stimulated emission depletion microscopy, and translation microscopy. The development of novel computational methods would greatly benefit super-resolution microscopy and lead to better resolution, improved accuracy, and faster image processing.
The brain integrates discrete but collinear stimuli to perceive global contours. Previous contour integration (CI) studies mainly focus on integration over space, and CI is attributed to either V1 long-range connections or contour processing in high-visual areas that top-down modulate V1 responses. Here, we show that CI also occurs over time in a design that minimizes the roles of V1 long-range interactions. We use tilted contours embedded in random orientation noise and moving horizontally behind a fixed vertical slit. Individual contour elements traveling up/down within the slit would be encoded over time by parallel, rather than aligned, V1 neurons. However, we find robust contour detection even when the slit permits only one viewable contour element. Similar to CI over space, CI over time also obeys the rule of collinearity. fMRI evidence shows that while CI over space engages visual areas as early as V1, CI over time mainly engages higher dorsal and ventral visual areas involved in shape processing, as well as posterior parietal regions involved in visual memory that can represent the orientation of temporally integrated contours. These results suggest at least partially dissociable mechanisms for implementing the Gestalt rule of continuity in CI over space and time.
Long-term measurements of particle number size distributions in combination with thermodenuder analysis have been performed since July 2003 at the Central European station of Melpitz, Germany. Up to the end of 2011, 20% of all investigated days during the 8.5 years of measurements showed new particle formation and subsequent growth. To investigate the role of various chemical compound candidates for condensational nanoparticle growth, we focused on nucleation events in which the measured size distributions with and without thermodesorption both showed growth patterns (accounting for up to similar to 85% of all nucleation events). In this study, particulate compounds that volatilize at 300 degrees C were specifically defined as "volatile," in contrast to "nonvolatile" compounds, which remain in the particulate phase after being heated to 300 degrees C. A strong correlation between ambient temperature and growth rate associated with volatile substances (except gaseous sulfuric acid) was found, which implies the importance of organics (possibly oxidized biogenic organic compounds) in particle growth at Melpitz. The contributions of the volatile compounds to the growth rate due to condensation of gaseous sulfuric acid and organics were found to be about 19% and 47%, respectively. The remaining similar to 25% was attributed to nonvolatile residuals, which appear to form gradually during the particle growth process and are characterized as extremely low-volatility compounds. The growth rate associated with volatile components exhibited significant seasonal variation, with the highest value during summertime, whereas the growth rate associated with the nonvolatile fraction showed less fluctuation.
The industrial sector is a major source of China's major CO2 emissions. In 2012, the emissions embedded in the final-use-induced intermediate CO2 flows contributed to approximately 91.2% of the total emissions. Hence, controlling CO2 emissions along supply chains could have a significant contribution in achieving the climate mitigation goal to which the Chinese government has been committed. In this study, we first extracted final-use induced CO2 transfer networks from input-output tables, and then applied the power-of-pull approach to the networks to identify the key sectors significantly affecting the CO2 emissions of each targeted sector's supply chains. Our results showed that each sector itself has significant power of pulling their emissions. Energy and raw material providers have played an essential role in pulling other sectors' emissions in the past years. The results of all sectors can easily construct a network reflecting the system's characteristics. And the power-of-pull approach could easily be integrated with the structural path analysis. Our proposed approach has the potential in helping policy making by offering a new perspective.
On the cover: The cover image, by Yanmei Dou et al., is based on the Research Article Postzygotic single‐nucleotide mosaicisms contribute to the etiology of autism spectrum disorder and autistic traits and the origin of mutations, Pages 1002–1013. DOI 10.1002/humu. 23284
The firework algorithm (FWA) is a novel swarm intelligence-based method recently proposed for the optimization of multi-parameter, nonlinear functions. Numerical waveform inversion experiments using a synthetic model show that the FWA performs well in both solution quality and efficiency. We apply the FWA in this study to crustal velocity structure inversion using regional seismic waveform data of central Gansu on the northeastern margin of the Qinghai-Tibet plateau. Seismograms recorded from the moment magnitude (MW) 5.4 Minxian earthquake enable obtaining an average crustal velocity model for this region. We initially carried out a series of FWA robustness tests in regional waveform inversion at the same earthquake and station positions across the study region, inverting two velocity structure models, with and without a low-velocity crustal layer; the accuracy of our average inversion results and their standard deviations reveal the advantages of the FWA for the inversion of regional seismic waveforms. We applied the FWA across our study area using three component waveform data recorded by nine broadband permanent seismic stations with epicentral distances ranging between 146 and 437 km. These inversion results show that the average thickness of the crust in this region is 46.75 km, while thicknesses of the sedimentary layer, and the upper, middle, and lower crust are 3.15, 15.69, 13.08, and 14.83 km, respectively. Results also show that the P-wave velocities of these layers and the upper mantle are 4.47, 6.07, 6.12, 6.87, and 8.18 km/s, respectively.
We present high-precision chemical abrasion-isotope dilution-thermal ionization mass spectrometry (CA-IDTIMS) U-Pb zircon and isotope dilution-negative-diennal ionization mass spectrometry (ID-N-TIMS) Re-Os molybdenite geochronology of the world class Tibetan Qulong porphyry Cu-NIo deposit. The data is used to constrain the timing, duration, and to yield implications for the ore -forming processes. The (-Pb data suggest that the preore Bonginuctiola pluton crystallized at 17.142 0.014/0.014/0.023 Ma (uncertainties presented as analytical /+ tracer /+ decay constant uncertainties), with emplacements of the synore P porphyry and postore quartz diorite occurring at 16.009 +/- 0.016/0.017/0.024 and 15.166 +/- 0.010/0.011/0.020 Ma, respectively. The Re-Os analysis of nudtiple independent molybdenite separations from single molybdenite-bearing quartz veins yields sub-%(0) level analytical precision (<1%(0)), which is comparable with that of modern CA[D-TINTSU-Pb zircon geochronology. The new Re-Os data indicate that the majority of the metals at Qulong were deposited over a minimum duration of 266 13 k.y., between 16.126 +/- 0.008/0.060/0.077 and 1.5.86 +/- 00.010/0.058/0.075 Ma, with die main phase of mineralization being broadly synchronous with the emplacement of die P porphyry. However, our Re-Os data of molybdenite hosted within the Rongmuctiola pillion imply that a portion of mineralizadon also predated die P porphyry and suggest that die P porphyry is an intermineral porphyry stock, although mineralization cut by P porphyry has not been previously documented or observed in this study. Correlating the Re-Os ages with vein types (A-B-D veins) demonstrates that the mineralization process was cyclical, with the presence of at least three short-lived (38 +/- 11 to 59 10 k.y.) mineralization pulses between 16.1.26 +/- 0.008 and 16.050 +/- 0.005, 16.040 +/- 0.007 and 15.981 +/- 0.007, and similar to 15.981 +/- 0.007 and 15.860 +/- 0.010 Ma. Coupling die Re-Os molybdenite ages and quartz (coprecipitated with die dated molybdenite) fluid inclusion data suggests that die cooling history was also cyclic, and implies a rapid cooling rate during the entire mineralization process (0.55 degrees +/- 0.11 C/k.y.), with much faster cooling rates (1.19 degrees +/- 0.82 degrees to 1.27 degrees +/- 0.53 degrees C/k.y.) for the individual mineralization pulses. The cyclic and rapid cooling process requires an additional cooling mechanism rather than the inefficient conduction, which we attribute to meteoric water circulation.The presence of mineralization predating the intermineral P porphyry stock and the absence of evidence of an early porphyry stock at Qulong suggest that mineralization potentially can take place without contemporaneous magmatism at mineralization levels. As a result, dating magmatic events may not necessarily bracket the entire mineralization duration of a porphyry system. This highlights the importance of dating ore minerals to reveal a comprehensive picture of the magma-hydrothermal process. In addition, the absence of contemporaneous magmatism during mineralization has broad implications for the classification of porphyry copper deposits and mineral exploration. The timescales of mineralization cycles constrained here via direct dating of ore minerals (tens of k.y.) are comparable with those recently proposed through high -precision U-Pb zircon dating, diffusion modeling, and numerical simulation. We propose that the cyclic mineralization pulses are linked with the periodic release of volatiles from the lower crustal magma chamber, which are common for porphyry copper systems worldwide. The episodic/cyclic metal enrichment process potentially is one of the controlling factors of porphyry copper ore formation and is the key to differentiate the formation of economic and subeconomic porphyry deposits.Finally, direct comparison of molybdenite Re-Os dates from different laboratories and with the zircon U-Pb system needs to account for the much larger uncertainties from tracer calibration and decay constants, respectively. As a result, we lose the necessary resolution to investigate the ore -forming process at the k.y. level. Therefore, to reduce these uncertainties, calibration between the two chronometers, using shared tracer solutions and a transparent data reduction platform within the community is required.
