Simple calibrated nonlinear excitation regime two-line atomic fluorescence thermometry.

Nonlinear excitation regime two-line atomic fluorescence (NTLAF) is a promising two-dimensional (2D) thermometry technique for turbulent sooty flames. However, the complexity of calibrating three system parameters and expensive instruments restricts the application of the current NTLAF technique. Here we propose a simple and cheap NTLAF measurement approach based on a one-parameter model and tunable diode laser absorption spectroscopy (TDLAS) calibration. Using this methodology, only one system parameter, instead of three as in traditional NTLAF, is to be calibrated by path-averaged temperature acquired by the TDLAS technique. As a demonstration, instantaneous 2D thermometry data of a homemade burner were acquired using this approach, with measurement uncertainty of ∼4.5% and deviation from both reference TDLAS results and Raleigh scattering measurement results less than 50 K, typically within 20 K. This approach offers a novel simplified NTLAF solution for noncontact, in-suit, high-resolution 2D temperature measurement and is expected to greatly improve the compatibility of the NTLAF technique in scientific research and engineering applications.

Spectroscopic super-resolution fluorescence cell imaging using ultra-small Ge quantum dots.

We demonstrate a spectroscopic imaging based super-resolution approach by separating the overlapping diffraction spots into several detectors during a single scanning period and taking advantage of the size-dependent emission wavelength in nanoparticles. This approach has been tested using off-the-shelf quantum dots (Invitrogen Qdot) and in-house novel ultra-small (~3 nm) Ge QDs. Furthermore, we developed a method-specific Gaussian fitting and maximum likelihood estimation based on a Matlab algorithm for fast QD localisation. This methodology results in a three-fold improvement in the number of localised QDs compared to non-spectroscopic images. With the addition of advanced ultra-small Ge probes, the number can be improved even further, giving at least 1.5 times improvement when compared to Qdots. Using a standard scanning confocal microscope we achieved a data acquisition rate of 200 ms per image frame. This is an improvement on single molecule localisation super-resolution microscopy where repeated image capture limits the imaging speed, and the size of fluorescence probes limits the possible theoretical localisation resolution. We show that our spectral deconvolution approach has a potential to deliver data acquisition rates on the ms scale thus providing super-resolution in live systems.

Characterization of odorous charge and photochemical reactivity of VOC emissions from a full-scale food waste treatment plant in China.

Food waste treatment plants (FWTPs) are usually associated with odorous nuisance and health risks, which are partially caused by volatile organic compound (VOC) emissions. This study investigated the VOC emissions from a selected full-scale FWTP in China. The feedstock used in this plant was mainly collected from local restaurants. For a year, the FWTP was closely monitored on specific days in each season. Four major indoor treatment units of the plant, including the storage room, sorting/crushing room, hydrothermal hydrolysis unit, and aerobic fermentation unit, were chosen as the monitoring locations. The highest mean concentration of total VOC emissions was observed in the aerobic fermentation unit at 21,748.2-31,283.3 µg/m3, followed by the hydrothermal hydrolysis unit at 10,798.1-23,144.4 µg/m3. The detected VOC families included biogenic compounds (oxygenated compounds, hydrocarbons, terpenes, and organosulfur compounds) and abiogenic compounds (aromatic hydrocarbons and halocarbons). Oxygenated compounds, particularly alcohols, were the most abundant compounds in all samples. With the use of odor index analysis and principal components analysis, the hydrothermal hydrolysis and aerobic fermentation units were clearly distinguished from the pre-treatment units, as characterized by their higher contributions to odorous nuisance. Methanthiol was the dominant odorant in the hydrothermal hydrolysis unit, whereas aldehyde was the dominant odorant in the aerobic fermentation unit. Terpenes, specifically limonene, had the highest level of propylene equivalent concentration during the monitoring periods. This concentration can contribute to the increase in the atmospheric reactivity and ozone formation potential in the surrounding air.

[Analysis of work-related fatigue characteristics and its influencing factors in scientific and technical personnel].

OBJECTIVE: To investigate the current status and characteristics of work-related fatigue among scientific and technical personnel and its associated factors, and to provide a scientific basis for further interventions. METHODS: A cross-sectional survey was conducted in the staff from a single scientific institution, using a self-administered questionnaire. Basic information of participants, Fatigue Scale-14, and Job Content Questionnaire were collected. RESULTS: The prevalence of work-related fatigue among the scientific and technical personnel was 54.6%; work-related fatigue was positively correlated with occupational stress (rs = 0.384, P < 0.05). Significant differences in the scores, proportions, and types of fatigue were found between different types of occupational stress. The associated factors of work-related fatigue included occupational stress profiles, social support, and educational status. A higher risk of work-related fatigue was found in the staff under high stress, compared with those under low stress (OR = 8.5, 95%CI = 3.9∼18.7). Social support served as a protective factor for work-related fatigue, while a higher level of education was correlated with more severe work-related fatigue. CONCLUSION: Work-related fatigue is common and serious among scientific and technical personnel, especially in those under high stress. Effective interventions according to occupational stress are of great importance to reduce work-related fatigue.

[GenomeLabTM GeXP analysis system to detect apoptosis-associated genes in A549 cells treated by recombinant human IL-24 combined with cisplatin].

Objective To investigate the changes of apoptosis-associated genes in human lung adenocarcinoma cell line A549 after treated by the recombinant human interleukin-24 (rhIL-24) combined with cisplatin (DDP). Methods The mRNA levels of Bax, Bcl-2, survivin, caspase-3, retinoblastoma (Rb) gene, p53 were analyzed by GenomeLabTM GeXP genetic analysis system after A549 cells were treated with 160 ng/mL rhIL-24 or 3 µg/mL DDP or 160 ng/mL rhIL-24 combined with 3 µg/mL DDP. Results The rhIL-24 up-regulated the levels of Bax, Rb, caspase-3 mRNAs and down-regulated Bcl-2, survivin mRNAs, but the change of p53 mRNA was not regular. The combination of rhIL-24 and DDP strengthened the above changes. Conclusion The rhIL-24 protein can induce the apoptosis of A549 cells by up-regulating Bax, caspase-3, Rb mRNAs and down-regulating Bcl-2, survivin mRNAs.

[Effects of recombinant human interleukin-24 alone and in combination with cisplatin on the growth of ovarian cancer cells in vitro].

OBJECTIVE: To investigate the inhibitory effects of recombinant human interleukin-24 (rhIL-24) on ovarian cancer cell lines SKOV3 and cisplatin (DDP)-resistant ovarian cancer cell lines SKOV3/DDP in vitro, and to observe the changes in apoptosis and cell cycle of SKOV3 and SKOV3/DDP. METHODS: Cell proliferation was detected by CCK8 assay, and the changes in apoptosis and cell cycle of SKOV3 and SKOV3/DDP were detected by flow cytometry after the treatment with rhIL-24 alone, DDP alone and rhIL-24 combined with DDP, respectively. RESULTS: The treatment with rhIL-24 significantly inhibited the growth of ovarian cancer cell lines SKOV3 and SKOV3/DDP in vitro. RhIL-24 combined with DDP resulted in a 30.7% growth inhibition, which showed a significant difference compared with the 6.5% growth inhibition in DDP alone group. The apoptosis rates detected by flow cytometry in rhIL-24 alone group, DDP alone group and combination group were 14.95%, 12.99% and 16.32%, respectively, which showed a significant difference compared with the apoptosis rate (1.32%) in negative control group. Furthermore, cell cycle detection indicated that the percentage of SKOV3 in G2 and S phases increased in rhIL-24 alone group, as well as in S phase in combination group. The percentage of SKOV3/DDP in G2 phase increased in rhIL-24 alone group, as well as in G1 phase in combination group. CONCLUSION: The treatment with rhIL-24 led to the growth inhibition of ovarian cancer cell lines SKOV3 and SKOV3/DDP, which was caused by apoptosis. And the inhibition effects of DDP could be enhanced after the treatment with combination therapy. rhIL-24 and combination therapy induced cell cycle arrest in G2 phase and G1 phase, respectively.

Super-resolution imaging strategies for cell biologists using a spinning disk microscope.

In this study we use a spinning disk confocal microscope (SD) to generate super-resolution images of multiple cellular features from any plane in the cell. We obtain super-resolution images by using stochastic intensity fluctuations of biological probes, combining Photoactivation Light-Microscopy (PALM)/Stochastic Optical Reconstruction Microscopy (STORM) methodologies. We compared different image analysis algorithms for processing super-resolution data to identify the most suitable for analysis of particular cell structures. SOFI was chosen for X and Y and was able to achieve a resolution of ca. 80 nm; however higher resolution was possible >30 nm, dependant on the super-resolution image analysis algorithm used. Our method uses low laser power and fluorescent probes which are available either commercially or through the scientific community, and therefore it is gentle enough for biological imaging. Through comparative studies with structured illumination microscopy (SIM) and widefield epifluorescence imaging we identified that our methodology was advantageous for imaging cellular structures which are not immediately at the cell-substrate interface, which include the nuclear architecture and mitochondria. We have shown that it was possible to obtain two coloured images, which highlights the potential this technique has for high-content screening, imaging of multiple epitopes and live cell imaging.

[Study on the knowledge of nutrition and related dietary behavior among "floating" women under pregnancy].

OBJECTIVE: The aim of this study was to assess the knowledge, attitude, practice (KAP) on nutrition and related influencing factors among the "floating" women under pregnancy. METHODS: 171 subjects in Chengdu, China were surveyed cross-sectionally by questionnaires. RESULTS: Most participants expressed a positive attitude towards nutrition and health, however, only 25.1% of the subjects under study had a better knowledge on nutrition and on healthy dietary practices. Frequency of the important foods (milk, egg, soy bean, nut, seafood etc.) intake were not enough during pregnancy. A significantly positive correlation was found between nutrition K, A and P (r = 0.322, 0.285, 0.173; P < 0.05). Level of education among the pregnant women under mobility and occupation of their husbands were the major contributing factors to their KAP level on nutrition (beta = 0.248, 0.312; P < 0.01). Medical staff, dietitians and specific books were the major sources of information on nutrition. CONCLUSION: More educational programs were needed to improve the knowledge and dietary behavior on nutrition to this population.