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The prevalence of human papillomavirus (HPV) genotype and cervical dysplasia in women older than 64 years, who are outside the Chinese cervical cancer screening age, has not been extensively studied. Here we conducted a retrospective analysis of women from a tertiary hospital in Guangzhou, aiming to provide meaningful advice for cervical cancer prevention and control in Guangzhou, China. In this study, the age-specific prevalence of any HPV genotypes showed a U-shaped pattern, and the second peak was observed among women >64 years, which was 19.27%. The top six HR HPV genotypes were HPV 16, HPV 52, HPV 58, HPV 31, HPV 33, and HPV 18. The persistence rate of any HPV in 24 months among women > 64 years was 33.33%, which was higher than that of women among 64 years, the proportion of cervical cancer (16.47%) was obviously higher than that in women aged 25-64 years (2.41%) ( PP=0.032) in women aged >64 years, with HPV+/NILM. In conclusion, the burden of HPV infection in women >64 years is heavy in Guangzhou. Re-evaluate cervical cancer screening strategies for women after age 64 is needed. And HPV 16/18/52/58 genotype model may be an alternative triage strategy to discover HSIL+ among women aged >64 years, with HPV+/NILM.

On-site simultaneous quantification of multiple contaminants in a water body is challenging, especially for parameters requiring complicated chemical reactions to measure such as Chemical Oxygen Demand (COD), ammonia nitrogen, and phosphate. A novel disposable multiplexed microfluidic device has been developed herein that allows the quantitative detection of up to five parameters at once. Solid reagent rather than commonly used liquid reagent was used to ensure long shelf life, and a "flow to dissolve" mechanism was provided accordingly for the thorough dissolution and mixing of a solid reagent on chip. Samples from river water and industrial wastewater were tested using the microfluidic chip, showing less than 15% deviation from results acquired with the traditional standard method. The test time though was only 1/6 of that required by the traditional method. In addition, the feasibility of using a smartphone to collect the colorimetric signal was discussed, and a data analysis method was provided for quantification purposes. The combination of the multiplexed chip and smartphone imaging provides a convenient and practical way to obtain accurate information on the water quality within a short period of time without the use of any sophisticated instruments.

Ammonia nitrogen pollution comes from a variety of sources, resulting in a wide distribution of concentrations and forms of existence across different samples. The on-site rapid detection of ammonia nitrogen in water is of great importance especially in unexpected water pollution accidents. In this paper, an inexpensive and portable microfluidic chip for the quantitative detection of ammonia nitrogen in water was developed. Solid reagents specific to ammonia nitrogen was pre-loaded in the microchannels and then liquid sample was introduced to initiate reactions that generated optical signals. A novel ���flow and react��� regime replying on accelerated dissolution and reaction was proposed, shortening reaction time and reducing reagent dosage significantly. Ammonia nitrogen concentration in the range of 0.3���10 ppm was determined successfully within 5 min with this chip and a fibre spectrophotometer.

Cosensitization of two dyes with different molecular sizes and photovoltaic characteristics is demonstrated to successfully prevent the “trade-off” effect, leading to an excellent power-conversion efficiency of 10.09% under one-sun and 11.12% under 0.3 sun 4 irradiation., In dye-sensitized solar cells (DSSCs), it is essential to use rational molecular design to obtain promising photosensitizers with well-matched energy levels and narrow optical band gaps. However, the “trade-off” effect between the photocurrent and photovoltage is still a challenge. Here we report four benzoxidazole based D–A–π–A metal-free organic dyes (WS-66, WS-67, WS-68 and WS-69) with different combinations of π-spacer units and anchoring-acceptor groups. Either extending the π-spacer or enhancing the electron acceptor can efficiently modulate the molecular energy levels, leading to a red-shift in the absorption spectra. The optimal dye, WS-69, containing a cyclopentadithiophene (CPDT) spacer and cyanoacetic acid acceptor, shows the narrowest energy band gap, which displays a very high photocurrent density of 19.39 mA cm–2, but suffers from a relatively low photovoltage of 696 mV, along with the so-called deleterious “trade-off” effect. A cosensitization strategy is further adopted for enhancing the device performance. Optimization of the dye loading sequence is found to be capable of simultaneously improving the photocurrent and photovoltage, and distinctly preventing the “trade-off” effect. The superior cosensitized cell exhibits an excellent power-conversion efficiency (PCE) of 10.09% under one-sun irradiation, and 11.12% under 0.3 sun irradiation, which constitutes a great achievement in that the efficiency of a pure metal-free organic dye with iodine electrolyte can exceed 11% even under relatively weak light irradiation. In contrast with the previous cosensitization strategy which mostly focused on compensation of light-harvesting, we propose a novel cosensitization architecture, in which the large molecular-sized, high photocurrent dye WS-69 takes charge of broadening the light-harvesting region to generate a high short-circuit current (J SC) while the small molecular-sized, high photovoltage dye WS-5 is responsible for retarding charge recombination to generate a high open-circuit voltage (V OC). In addition, adsorption amount and photo-stability studies suggest that the cyano group in the anchoring acceptor is important for the stability since it is beneficial towards decreasing the LUMO levels and enhancing the binding of dyes onto TiO2 nanocrystals.

Dye-sensitized solar cells (DSSCs) based on Cu-II/I bipyridyl or phenanthroline complexes as redox shuttles have achieved very high open-circuit voltages (V-OC, more than 1 V). However, their short-circuit photocurrent density (J(SC)) has remained modest. Increasing the J(SC) is expected to extend the spectral response of sensitizers to the red or NIR region while maintaining efficient electron injection in the mesoscopic TiO2 film and fast regeneration by the Cu-I complex. Herein, we report two new D-A-pi-A-featured sensitizers termed HY63 and HY64, which employ benzothiadiazole (BT) or phenanthrene-fused-quinoxaline (PFQ), respectively, as the auxiliary electron-withdrawing acceptor moiety. Despite their very similar energy levels and absorption onsets, HY64-based DSSCs outperform their HY63 counterparts, achieving a power conversion efficiency (PCE) of 12.5 %. PFQ is superior to BT in reducing charge recombination resulting in the near-quantitative collection of photogenerated charge carriers.