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Tropospheric ozone variability occurs because of multiple forcing factors including surface emission of ozone precursors, stratosphere-to-troposphere transport (STT), and meteorological conditions. Analyses of ozonesonde observations made in Huntsville, AL, during the peak ozone season (May to September) in 2013 indicate that ozone in the planetary boundary layer was significantly lower than the climatological average, especially in July and August when the Southeastern United States (SEUS) experienced unusually cool and wet weather. Because of a large influence of the lower stratosphere, however, upper tropospheric ozone was mostly higher than climatology, especially from May to July. Tropospheric ozone anomalies were strongly anticorrelated (or correlated) with water vapor (or temperature) anomalies with a correlation coefficient mostly about 0.6 throughout the entire troposphere. The regression slopes between ozone and temperature anomalies for surface up to midtroposphere are within 3.0-4.1 ppbv K−1. The occurrence rates of tropospheric ozone laminae due to STT are ≥50% in May and June and about 30% in July, August, and September suggesting that the stratospheric influence on free-tropospheric ozone could be significant during early summer. These STT laminae have a mean maximum ozone enhancement over the climatology of 52 ± 33% (35 ± 24 ppbv) with a mean minimum relative humidity of 2.3 ± 1.7%. [ABSTRACT FROM AUTHOR]

The Tropospheric Ozone Lidar Network (TOLNet) is a unique network of lidar systems that measure high-resolution atmospheric profiles of ozone. The accurate characterization of these lidars is necessary to determine the uniformity of cross-instrument calibration. From July to August 2014, three lidars, the TROPospheric OZone (TROPOZ) lidar, the Tunable Optical Profiler for Aerosol and oZone (TOPAZ) lidar, and the Langley Mobile Ozone Lidar (LMOL), of TOLNet participated in the "Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ) mission and the "Front Range Air Pollution and Photochemistry Éxperiment" (FRAPPÉ) to measure ozone variations from the boundary layer to the top of the troposphere. This study presents the analysis of the intercomparison between the TROPOZ, TOPAZ, and LMOL lidars, along with comparisons between the lidars and other in situ ozone instruments including ozonesondes and a P-3B airborne chemiluminescence sensor. In terms of the range-resolving capability, the TOLNet lidars measured vertical ozone structures with an accuracy generally better than ±15% within the troposphere. Larger differences occur at some individual altitudes in both the near-field and far-field range of the lidar systems, largely as expected. In terms of column average, the TOLNet lidars measured ozone with an accuracy better than ±5% for both the intercomparison between the lidars and between the lidars and other instruments. These results indicate very good measurement accuracy for these three TOLNet lidars, making them suitable for use in air quality, satellite validation, and ozone modeling efforts. [ABSTRACT FROM AUTHOR]

Our present aim was to investigate whether changes in the expression of αβ nicotinic acetylcholine receptor (nAChR) in patients with vascular dementia (VaD) and ischemic rats are related to cognitive scores. Blood leukocytes for 59 Chinese patients with VaD (diagnosed on the basis of clinical guidelines) and 31 cases as age-matched controls were examined, and the animal model established employing Pulsinelli's four-vessel occlusion. The levels of α and β subunit mRNA in leukocytes and the hippocampus were analyzed by real-time PCR, and the protein level in the hippocampus by Western blotting. The mini-mental state examination was utilized to characterize the intellectual capacity of the patients with reference to the DSM IV diagnosis and Hachinski Ischemic Scale score, and the Morris Water Maze test to assess the ability of learning and memory of the rats. In patients, the level of α mRNA, but not β, in blood leukocytes was clearly lowered, which was significantly correlated to their clinical cognitive test scores. Smoking exerted no impact on the level of α mRNA in the present study. In the blood leukocytes and the hippocampus of the brains of the ischemic rats, the levels of both α and β mRNA were lowered, and the proteins of these subunits in the hippocampus were decreased. The changes of α and β mRNA in blood leukocytes, and their protein levels in the hippocampus were significantly correlated with impaired learning and memory. These findings indicate that alterations in expression of the αβ subtype of nAChR may be involved in the molecular mechanism(s) underlying the cognitive deficit associated with VaD. [ABSTRACT FROM AUTHOR]

Objective: To investigate the modulatory effect of acupuncture treatment on the resting-state functional connectivity of brain regions in migraine without aura (MWoA) patients. Methods: Twelve MWoA patients were treated with standard acupuncture treatment for 4 weeks. All MWoA patients received resting-state functional magnetic resonance imaging (fMRI) scanning before and after acupuncture treatment. Another 12 normal subjects matched in age and gender were recruited to serve as healthy controls. The changes of restingstate functional connectivity in MWoA patients before and after the acupuncture treatment and those with the healthy controls were compared. Results: Before acupuncture treatment, the MWoA patients had significantly decreased functional connectivity in certain brain regions within the frontal and temporal lobe when compared with the healthy controls. After acupuncture treatment, brain regions showing decreased functional connectivity revealed significant reduction in MWoA patients compared with before acupuncture treatment. Conclusions: Acupuncture treatment could increase the functional connectivity of brain regions in the intrinsic decreased brain networks in MWoA patients. The results provided further insights into the interpretation of neural mechanisms of acupuncture treatment for migraine. [ABSTRACT FROM AUTHOR]

Shenmu bituminous coal was pyrolyzed and then gasified in a 10 t/h circulating fluidized bed of coal fast pyrolysis system to investigate the operation characteristics, coal pyrolysis characteristics and product distribution in the fluidized bed pyrolysis reactor. The results show that the contents of H2 and CH4 is high in pyrolysis gas with the low heat value of about 11~15 MJ/m³. The tar distillation range analysis demonstrate that light fraction content is about 47.00%. Proximate analysis of semi-coke clearly displays that the content of fixed carbon content is high and that of volatile is low. [ABSTRACT FROM AUTHOR]

PURPOSE: To observe the effect of clinical application of Benex extractor in minimally invasive tooth extraction. METHODS: Root canals of 81 teeth in 56 cases were prepared, crew thread pegs were inserted and circled tightly, and then extractors were loaded. With traction principle, the teeth were extracted with Benex extractor. RESULTS: Seventy -seven teeth in 52 cases were succe ssfully removed without radical fracture and no serious post -extraction reaction was reported. Four teeth in 4 cases failed to be extracted. The success ratio was 95%. CONCLUSIONS: Benex extractor is an effective way of minimally invasive tooth extraction for its simple and convenient application. [ABSTRACT FROM AUTHOR]

The photodynamic therapy (PDT) of cancer is limited by tumor hypoxia as PDT efficiency depends on O 2 concentration. A novel oxygen self-sufficient photosensitizer (Ru-g-C 3 N 4) was therefore designed and synthesized via a facile one-pot method in order to overcome tumor hypoxia-induced PDT resistance. The photosensitizer is based on [Ru(bpy) 2 ]2+ coordinated to g-C 3 N 4 nanosheets by Ru–N bonding. Compared to pure g-C 3 N 4 , the resulting nanosheets exhibit increased water solubility, stronger visible light absorption, and enhanced biocompatibility. Once Ru-g-C 3 N 4 is taken up by hypoxic tumor cells and exposed to visible light, the nanosheets not only catalyze the decomposition of H 2 O 2 and H 2 O to generate O 2 , but also catalyze H 2 O 2 and O 2 concurrently to produce multiple ROS (•OH, •O 2 −, and 1O 2). In addition, Ru-g-C 3 N 4 affords luminescence imaging, while continuously generating O 2 to alleviate hypoxia greatly improving PDT efficacy. To the best of our knowledge, this oxygen self-sufficient photosensitizer produced via grafting a metal complex onto g-C 3 N 4 is the first of its type to be reported. A novel oxygen self-sufficient photosensitizer (Ru-g-C 3 N 4) was constructed from cis -Ru 2 (bpy) 2 Cl 2 and g-C 3 N 4 by Ru–N coordination to achieve enhanced PDT in hypoxia. Ru-g-C 3 N 4 not only catalyze the decomposition of H 2 O 2 and H 2 O to generate O 2 , but also catalyze H 2 O 2 and O 2 concurrently to produce multiple ROS (•OH, •O 2 −, and 1O 2) for the treatment of cancer both in vitro and in vivo. Moreover, Ru-g-C 3 N 4 can be used for in vivo luminescence imaging to allow highly precise treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

The Tropospheric Ozone Lidar Network (TOLNet) was used to validate retrievals of ozone (O 3) profiles in the troposphere from the TROPOspheric Monitoring Instrument (TROPOMI) ultraviolet (UV), Cross-track Infrared Sounder (CrIS) infrared (IR), and a combined UV + IR wavelength retrieval from TROPOMI/CrIS. Observations from six separate ground-based lidar systems and various locations of ozonesondes distributed throughout North America and in the Netherlands were used to quantify systematic bias and random errors for each satellite retrieval. Furthermore, TOLNet data were used to intercompare idealized UV, IR, and UV + IR convolved lidar profiles of O 3 in the troposphere during case studies representative of high-O 3 events. This study shows that the improved sensitivity and vertical resolution in UV + IR retrievals in the middle- and upper-troposphere resulted in tropospheric degree of freedom (DOF) values ∼ 33 % higher compared to UV- and IR-only retrievals. The increased DOFs in the UV + IR retrievals allowed for improved reproduction of mid- and upper-tropospheric O 3 enhancements and, to a lesser degree, near-surface pollution enhancements compared to single-wavelength satellite products. The validation of O 3 profiles in the troposphere retrieved with the UV-only, IR-only, and UV + IR Tikhonov regularised Ozone Profile retrievAl with SCIATRAN (TOPAS) algorithm developed at the Institute for Environmental Physics, University of Bremen, demonstrated the utility of using TOLNet as a satellite evaluation data set. TOPAS UV-only, IR-only, and UV + IR wavelength retrievals had systematic biases, quantified with normalized mean bias, throughout the troposphere of 11.2 ppb (22.1 %), -1.7 ppb (-0.3 %), and 3.5 ppb (7.8 %), respectively, which meet the tropospheric systematic bias requirements defined by the science teams for the TROPOMI and CrIS sensors. The primary drivers of systematic bias were determined to be solar zenith angle, surface albedo, and cloud fraction. Random errors, representative of uncertainty in the retrievals and quantified by root mean squared errors (RMSEs), were large for all three retrievals, with UV-only, IR-only, and UV + IR wavelength retrievals having RMSEs throughout the troposphere of 17.4 ppb (19.8 % of mean tropospheric column values), 10.5 ppb (12.6 % of mean tropospheric column values), and 14.0 ppb (14.6 % of mean tropospheric column values), respectively. TOPAS UV-only profiles did not meet the uncertainty requirements defined for TROPOMI for the troposphere; however, CrIS IR-only retrievals did meet the uncertainty requirements defined by this mission. The larger random errors reflect the challenge of retrieving daily O 3 profiles due to the limited sensitivity and vertical resolution of these retrievals in the troposphere. Tropospheric systematic biases and random error were lower in IR-only and combined UV + IR retrievals compared to UV-only products due to the increased sensitivity in the troposphere allowing the retrievals to deviate further from the a priori profiles. Observations from TOLNet demonstrated that the performance of the three satellite products varied by season and altitude in the troposphere. TOLNet was shown to result in similar validation statistics compared to ozonesonde data, which are a commonly used satellite evaluation data source, demonstrating that TOLNet is a sufficient source of satellite O 3 profile validation data in the troposphere, which is critical as this data source is the primary product identified for the tropospheric O 3 validation of the recently launched Tropospheric Emissions: Monitoring of Pollution (TEMPO) mission. [ABSTRACT FROM AUTHOR]