Publications by authors named "Qingqing Dong"

8 Publications

  • Page 1 of 1

Investigation of aerosol absorption with dual-polarization lidar observations.

Opt Express 2020 Mar;28(5):7028-7035

Polarization lidar has been widely used in recent decades to observe the vertical structures of aerosols and clouds in the atmosphere. We developed a dual-polarization lidar system that can detect polarization measurements simultaneously at 355 nm and 532 nm. Dust events and haze episodes over northern China in 2014 were observed by the developed lidar. The results showed that the dust-dominated aerosol depolarization ratios at 532 nm were larger than those at 355 nm, but those of the air pollutants were smaller, indicating that this tool could provide a more accurate classification of aerosols. Moreover, we found a good relationship between the absorption coefficient of aerosols and the ratio of depolarization ratios at 532 nm and 355 nm for dust aerosols. Our results imply that aerosol absorption from polarization measurements may be determined by lidar at the ultraviolet and visible wavelengths.
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http://dx.doi.org/10.1364/OE.390475DOI Listing
March 2020

Ten-year global particulate mass concentration derived from space-borne CALIPSO lidar observations.

Sci Total Environ 2020 Jun 5;721:137699. Epub 2020 Mar 5.

Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China.

Passive remote sensing has been widely used in recent decades to obtain global particulate matter (PM) mass concentration at daytime and under cloud-free condition. In this study, a retrieval method was developed for providing PM (PM and PM) mass concentration both at daytime and nighttime using the latest data version (V4.10) from space-borne Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) lidar measurements. The advantage of the method is that PM & PM mass concentrations were obtained for seven aerosol types respectively base on active remote sensing observation at daytime and nighttime, even under cloudy condition. The results show that satellite-based PM mass concentrations are in good agreement with in-situ observations from 1602 ground monitoring sites throughout the world. Moreover, global distributions of PM and PM mass concentration during 2007-2016 were investigated, showing that for Beijing the annual mean PM mass concentration at nighttime is 11.31% less than those at daytime, however for London is 36.62%. It is suggested that diurnal variations in PM mass concentration are closely related to human activities. This work provides a reliable high-resolution database for long-term particulate mass concentrations on the global scale, which is of importance to evaluate aerosol impacts on climate, environment as well as ecosystem.
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http://dx.doi.org/10.1016/j.scitotenv.2020.137699DOI Listing
June 2020

Clinical recovery after 5 level of posterior decompression spine surgeries in patients with cervical spondylotic myelopathy: A retrospective cohort study.

Asian J Surg 2020 May 31;43(5):613-624. Epub 2019 Aug 31.

Department of Outpatient, Ankang Hospital of Traditional Chinese Medicine, Ankang, Shaanxi, 725000, China. Electronic address:

Background/objective: The selection of surgical technique in patients with cervical spondylotic myelopathy relies on the surgeon(s) and patients' conditions. The objectives of the study were to test the hypotheses that French-door laminoplasty recovers faster than laminectomy and has good outcome measures.

Methods: Data regarding surgical, radiological, and clinical outcome measures of 330 patients with cervical spondylotic myelopathy operated under French-door laminoplasty (fdLP group, n = 110), open-door laminoplasty (odLP group, n = 110), or laminectomy (LC group, n = 110) were collected from the records of institute and analyzed.

Results: Patients of fdLP group (p < 0.0001, q = 11.65) and odLP group (p < 0.0001, q = 11.27) both had significantly improved modified Rankin scale score than those of LC group. In addition, patients of fdLP group had minimum blood loss during operations and that was maximum for patients of the LC group. Unlike patients of fdLP group (p < 0.0001, q = 80) and LC group (p < 0.0001, q =122), those of odLP group had lost more amount of cervical lordotic after surgery. Open-door laminoplasty had significantly reduced cervical range of motion than laminectomy (p < 0.0001, q = 15.45) and French-door laminoplasty (p < 0.0001, q = 13.45). After 12-months, fdLP group had higher bone union rate than odLP group (p = 0.007, q = 3.395) and LC group (p = 0.007, q = 4.243). French door laminoplasty had a better postoperative quality of life.

Conclusions: Among the posterior decompression spine surgeries, French-door laminoplasty is superior surgical procedure than laminectomy and could be superior surgical technique than open-door laminoplasty.
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http://dx.doi.org/10.1016/j.asjsur.2019.08.003DOI Listing
May 2020

TGF-β1 and TIMP1 double directional rAAV targeted by UTMD in atherosclerotic vulnerable plaque.

Exp Ther Med 2017 Apr 6;13(4):1465-1469. Epub 2017 Feb 6.

Department of Ultrasound, Shanghai General Hospital Affiliated to Nanjing Medical University, Shanghai 200080, P.R. China.

In the present study, we determined whether ultrasound-targeted microbubble destruction (UTMD) combined with dual targeting of transforming growth factor (TGF)-β1 and tissue inhibitors of metalloproteinase (TIMP) 1 recombinant adeno-associated virus (rAAV) can stabilize atherosclerotic vulnerable plaques. First, we used rabbit model to detect the TGF-β1/TIMP1 virus therapy result. H&E staining was used to evaluate the tissues. The protein levels of TGF-β1 and TIMP1 were detected in rabbit models. The THP-1 cells were induced into macrophages, and transfected with TGF-β1 and TIMP1 rAAV under optimized UTMD. The expression of TGF-β1 and TIMP1 was measured by RT-PCR and western blotting. We found that the apoptotic rates were induced when compared to the control group. The rAAV virus group showed a significant decrease in the p-ERT and p-AKT expression. These data support the hypothesis that TGF-β1 and TIMP1 are crucial in the regulation of atherosclerotic plaques.
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http://dx.doi.org/10.3892/etm.2017.4101DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5377323PMC
April 2017

Scutellaria baicalensis Georgi extract protects against alcohol‑induced acute liver injury in mice and affects the mechanism of ER stress.

Mol Med Rep 2016 Apr 23;13(4):3052-62. Epub 2016 Feb 23.

Department of Pharmacy, Bengbu Medical College, Bengbu, Anhui 233030, P.R. China.

The aims of the present study were to examine the hepatoprotective effect of Scutellaria baicalensis Georgi extract (Scutellariae Radix extract; SRE) against acute alcohol‑induced liver injury in mice, and investigate the mechanism of endoplasmic reticulum (ER) stress. High performance liquid chromatography was used for the phytochemical analysis of SRE. Animals were administered orally with 50% alcohol (12 ml/kg) 4 h following administration of doses of SRE every day for 14 days, with the exception of normal control group. The protective effect was investigated by measuring the levels of aspartate transaminase (AST), alanine transferase (ALT) and triglyceride (TG) in the serum, and the levels of glutathione (GSH) and malondialdehyde (MDA) in liver tissues. The levels of glucose‑related protein 78 (GRP78) were detected using immunohistochemical localization and an enzyme‑linked immunosorbent assay. Hepatocyte apoptosis was assessed using terminal‑deoxynucleoitidyl transferase mediated nick end labeling. The SRE contained 31.2% baicalin. Pretreatment with SRE had a marked protective effect by reversing the levels of biochemical markers and levels of GRP78 in a dose‑dependent manner. The results of the present study demonstrated that pretreatment with SRE exerted a marked hepatoprotective effect by downregulating the expression of GRP78, which is a marker of ER stress.
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http://dx.doi.org/10.3892/mmr.2016.4941DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4805105PMC
April 2016

Easily accessible polymer additives for tuning the crystal-growth of perovskite thin-films for highly efficient solar cells.

Nanoscale 2016 Mar;8(10):5552-8

Laboratory of Advanced Optoelectronic Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China.

For perovskite solar cells (Pero-SCs), one of the key issues with respect to the power conversion efficiency (PCE) is the morphology control of the perovskite thin-films. In this study, an easily-accessible additive polyethylenimine (PEI) is utilized to tune the morphology of CH3NH3PbI3-xClx. With addition of 1.00 wt% of PEI, the smoothness and crystallinity of the perovskite were greatly improved, which were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). A summit PCE of 14.07% was achieved for the p-i-n type Pero-SC, indicating a 26% increase compared to those of the devices without the additive. Both photoluminescence (PL) and alternating current impedance spectroscopy (ACIS) analyses confirm the efficiency results after the addition of PEI. This study provides a low-cost polymer additive candidate for tuning the morphology of perovskite thin-films, and might be a new clue for the mass production of Pero-SCs.
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http://dx.doi.org/10.1039/c6nr00206dDOI Listing
March 2016

[An improved software design of ultrasound bone densitometer].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2014 Oct;31(5):1061-4

In order to meet the requirements of ultrasound bone density measurement, we proposed a software solution to improve the accuracy and speed of measurement of bone mineral density of the ultrasound bone densitometer. We used a high-speed USB interface chip FT232H, along with a high-speed AD converter chip to calculate speed of sound (SOS), broadband ultrasound attenuation (BUA ) and other bone density parameters in the PC software. This solution improved the accuracy of the measurement data, reduced the measurement time and increased the quality of the displayed image. It is well concluded that the new software can greatly improve the accuracy and transmission speed of bone density measurement data through a high-speed USB interface and a software data processing technology.
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October 2014

Triple cathode buffer layers composed of PCBM, C60, and LiF for high-performance planar perovskite solar cells.

ACS Appl Mater Interfaces 2015 Mar 12;7(11):6230-7. Epub 2015 Mar 12.

†Laboratory of Advanced Optoelectronic Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, China.

In this paper, triple cathode buffer layers (CBLs) composed of phenyl-C61-butyric acid methyl ester (PCBM), C60, and LiF layers were introduced into the planar p-i-n perovskite solar cells (p-i-n PSCs) with a device structure of ITO/PEDOT:PSS/CH3NH3PbI3-xClx/CBLs/Al. For comparison, a single CBL of PCBM and a double CBL of PCBM/LiF were also investigated in the p-i-n PSCs. On the basis of the PCBM buffer layer, the addition of a thin LiF layer facilitated the charge collection process and led to the dramatic improvement of the power conversion efficiency (PCE) of the PSCs up to 14.69% under an illumination of AM 1.5G, 100 mW/cm(2), which is to date one of the highest efficiencies of the p-i-n PSCs. By further insertion of a C60 layer between PCBM and LiF in the triple CBLs, a PCE of 14.24% was obtained, and more importantly, the PCBM/C60/LiF triple CBLs are very helpful for improving the stability of the devices and making the LiF layer less thickness-sensitive for achieving high performances of the p-i-n PSCs.
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http://dx.doi.org/10.1021/acsami.5b00468DOI Listing
March 2015
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