-
Scientific Reports Jul 2018Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) provides three-dimensional information on aerosol optical properties across the globe....
Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) provides three-dimensional information on aerosol optical properties across the globe. However, the performance of CALIPSO aerosol optical depth (AOD) products under different air quality conditions remains unclear. In this research, three years of CALIPSO level 2 AOD data (November 2013 to December 2017) were employed to compare with the Moderate Resolution Imaging Spectroradiometer (MODIS) level 2 columnar AOD products and ground-based sun photometer measurements for the same time period. To investigate the effect of air quality on AODs retrieved from CALIPSO, the AODs obtained from CALIPSO, MODIS, and sun photometer were inter-compared under different air quality conditions over Wuhan and Dengfeng. The average absolute bias of AOD between CALIPSO and sun photometer was 0.22 ± 0.21, 0.11 ± 0.07, and 0.14 ± 0.13 under clean, moderate, and polluted weather, respectively. The result indicates that the CALIPSO AOD were more reliable under moderate and polluted days. Moreover, the deviation of AOD between CALIPSO and sun photometer was largest (0.23 ± 0.21) in the autumn season, and lowest (0.13 ± 0.12) in the winter season. The results show that CALIPSO AOD products were more applicable to regions and seasons with high aerosol concentrations.
PubMed: 29968814
DOI: 10.1038/s41598-018-28417-7 -
PeerJ 2024Salt stress is one of the significant abiotic stress factors that exert harmful effects on plant growth and yield. In this study, five cultivars of mung bean ( L.) were...
Salt stress is one of the significant abiotic stress factors that exert harmful effects on plant growth and yield. In this study, five cultivars of mung bean ( L.) were treated with different concentrations of NaCl and also inoculated with a salt-tolerant bacterial strain to assess their growth and yield. The bacterial strain was isolated from the saline soil of Sahiwal District, Punjab, Pakistan and identified as . Plant growth was monitored at 15-days interval and finally harvested after 120 days at seed set. Both sodium and potassium uptake in above and below-ground parts were assessed using a flame photometer. Fresh and dry mass, number of pods, seeds per plant, weight of seeds per plant and weight of 100 seeds reduced significantly as the concentration of NaCl increased from 3 to 15 dSm. There was a significant reduction in the growth and yield of plants exposed to NaCl stress without bacterial inoculum compared to the plants with bacterial inoculum. The latter plants showed a significant increase in the studied parameters. It was found that the cultivar Inqelab mung showed the least reduction in growth and yield traits among the studied cultivars, while Ramzan mung showed the maximum reduction. Among all the cultivars, maximum Na uptake occurred in roots, while the least uptake was observed in seeds. The study concludes that NaCl stress significantly reduces the growth and yield of mung bean cultivars, but inoculum alleviates salt stress. These findings will be helpful to cultivate the selected cultivars in soils with varying concentrations of NaCl.
Topics: Bacillus; Vigna; Sodium Chloride; Salt Stress; Potassium; Pakistan; Soil Microbiology; Sodium; Seeds; Plant Roots; Salt Tolerance
PubMed: 38854802
DOI: 10.7717/peerj.17465 -
Clinical & Experimental Optometry Sep 2010This review compares the results of studies that have investigated the impact of lutein and zeaxanthin supplementation on macular pigment optical density (MPOD) with... (Review)
Review
This review compares the results of studies that have investigated the impact of lutein and zeaxanthin supplementation on macular pigment optical density (MPOD) with those that have investigated the reliability of techniques used to measure macular pigment optical density. The review will focus on studies that have used heterochromatic flicker photometry for measurement of macular pigment optical density, as this is the only technique that is currently available commercially to clinicians. We identified articles that reported on supplementation with lutein and/or zeaxanthin and/or meso-zeaxanthin on macular pigment optical density measurement techniques published in peer-reviewed journals, through a multi-staged, systematic approach. Twenty-four studies have investigated the repeatability of MPOD measurements using heterochromatic flicker photometry. Of these, 10 studies provided a coefficient of repeatability or data from which the coefficient could be calculated, with a range in values of 0.06 to 0.58. The lowest coefficient of repeatability assessed on naïve subjects alone was 0.08. These values tell us that, at best, changes greater than 0.08 can be considered clinically significant and at worst, only changes greater than 0.58 can be considered clinically significant. Six studies assessed the effect of supplementation with up to 20 mg/day lutein on macular pigment optical density measured using heterochromatic flicker photometry and the mean increase in macular pigment optical density ranged from 0.025 to 0.09. It seems reasonable to conclude that the chance of eliciting an increase in macular pigment optical density during six months of daily supplementation with between 10 and 20 mg lutein that is of sufficient magnitude to be detected by using heterochromatic flicker photometry on an individual basis is small. Commercially available heterochromatic flicker photometers for macular pigment optical density assessment in the clinical environment appear to demonstrate particularly poor coefficient of repeatability values. Clinicians should exercise caution when considering the purchase of these instruments for potential monitoring of macular pigment optical density in response to supplementation in individual patients.
Topics: Dietary Supplements; Flicker Fusion; Humans; Lutein; Photometry; Retinal Pigments; Xanthophylls; Zeaxanthins
PubMed: 20629669
DOI: 10.1111/j.1444-0938.2010.00499.x -
Journal of Occupational and... Apr 2018This experimental study aimed to evaluate airborne particulates and volatile organic compounds (VOCs) from surgical smoke when a local exhaust ventilation (LEV) system...
This experimental study aimed to evaluate airborne particulates and volatile organic compounds (VOCs) from surgical smoke when a local exhaust ventilation (LEV) system is in place. Surgical smoke was generated from human tissue in an unoccupied operating room using an electrocautery surgical device for 15 min with 3 different test settings: (1) without LEV control; (2) control with a wall irrigation suction unit with an in-line ultra-low penetration air filter; and (3) control with a smoke evacuation system. Flow rate of LEVs was approximately 35 L/min and suction was maintained within 5 cm of electrocautery interaction site. A total of 6 experiments were conducted. Particle number and mass concentrations were measured using direct reading instruments including a condensation particle counter (CPC), a light-scattering laser photometer (DustTrak DRX), a scanning mobility particle sizer (SMPS), an aerodynamic particle sizer (APS), and a viable particle counter. Selected VOCs were collected using evacuated canisters using grab, personal and area sampling techniques. The largest average particle and VOCs concentrations were found in the absence of LEV control followed by LEV controls. Average ratios of LEV controls to without LEV control ranged 0.24-0.33 (CPC), 0.28-0.39 (SMPS), 0.14-0.31 (DustTrak DRX), and 0.26-0.55 (APS). Ethanol and isopropyl alcohol were dominant in the canister samples. Acetaldehyde, acetone, acetonitrile, benzene, hexane, styrene, and toluene were detected but at lower concentrations (<500 μg/m) and concentrations of the VOCs were much less than the National Institute for Occupational Safety and Health recommended exposure limit values. Utilization of the LEVs for surgical smoke control can significantly reduce but not completely eliminate airborne particles and VOCs.
Topics: Air Pollutants, Occupational; Electrocoagulation; Humans; Occupational Exposure; Particulate Matter; Smoke; Ventilation; Volatile Organic Compounds
PubMed: 29283318
DOI: 10.1080/15459624.2017.1422082 -
Poultry Science May 2024A total of 720 male Cobb 500 broiler chicks were used in a 5 treatment and 8 replicate experiment to explore dynamic changes in blood metabolites in response to...
A total of 720 male Cobb 500 broiler chicks were used in a 5 treatment and 8 replicate experiment to explore dynamic changes in blood metabolites in response to short-term nutrient depletion and repletion. Day old chicks were offered a corn and soybean meal-based common starter diet from d1 to 14 that was formulated to meet all nutrient requirements of the birds. From d15 to 17, the experimental diets were offered, before returning all groups to a common diet from d18 to 20, at which point the experiment was terminated. A total of 5 experimental diets were designed. A standard grower diet served as a control and was offered to 1 of the 5 groups of chicks. The additional 4 experimental groups comprised diets that were low in digestible phosphorus (P), total calcium (Ca), crude protein and digestible amino acids (AA) or apparent metabolizable energy (AME). The common grower diet that was offered from d18-20 was designed to be nutritionally complete and was intended to explore dynamic response to nutrient repletion. Blood was drawn from 8 chicks per treatment at time 0 (immediately prior to introduction of the experimental diets) and then again 3, 6, 12, 24, and 48h after introduction of the nutrient depleted diets. Additionally, blood was drawn 3, 6, 12, 24, and 48h after the introduction of the nutritionally complete common grower diet. Chicks were not sampled more than once. Feed intake, body weight and feed conversion ratio (FCR) were assessed on d14, 17, and 20. Blood metabolites were analyzed using the iSTAT Alinity V handheld blood analyzer, the Vetscan VS2 Chemistry Analyzer and the iCheck Carotene Photometer. Live performance metrics were not affected by the short-term nutrient depletion and all chicks grew normally throughout the experiment. The diet with low digestible P generated a rapid temporary decrease in plasma P and an increase in plasma Ca, that were returned to baseline following the re-introduction of the common grower feed. Introduction of the diet with low total Ca resulted in a significant increase in plasma P, effects which were also mitigated during the nutrient repletion phase. Total plasma protein, albumin and uric acid (UA) were decreased, and plasma glucose increased, in the chicks that received the diet with low crude protein and digestible AA. There was a delayed increase in aspartate amino transaminase (AST) associated with the diets with low digestible P and low AME. These results demonstrate the capacity of blood biochemistry to adapt to quantitative and qualitative changes in nutrient intake. Point-of-care analysis of blood biomarkers offers nutritionists a valuable opportunity to calibrate nutritional matrices for common dietary ingredients, zootechnical feed additives and to optimize diet phase changes. It can be concluded that many blood biomarkers are plastic to changes in diet nutrient density and offer an objective index for optimization of nutritional programs for commercial broiler production.
PubMed: 38823292
DOI: 10.1016/j.psj.2024.103859 -
Indian Journal of Community Medicine :... 2018High sodium intake is a major public health concern. Sodium consumption pattern of West Indian population has never been reported before.
BACKGROUND
High sodium intake is a major public health concern. Sodium consumption pattern of West Indian population has never been reported before.
OBJECTIVES
The cross-sectional study assessed sodium intake pattern by considering all possible dietary sources and spot urine sodium estimation among sedentary healthy adults of productive age group (35-55 years).
MATERIALS AND METHODS
Twenty-four-h dietary recall (3 alternative days in a week), food frequency assessment, weighing of table, and cooking salt ( = 218) were performed. Spot urine samples were collected for subset ( = 33) to quantify sodium excretion. Flame photometer "CL 361" was used for food sodium quantification.
RESULTS
Men had higher sodium intake than women (3.9 ± 0.4 vs. 3.8 ± 0.4 g/day). Significantly higher sodium intake among men was from processed ready to eat foods (0.8 ± 0.3 vs. 0.6 ± 0.1, < 0.05) and among women was from cooking and table salt (2.6 ± 0.3 vs. 2.8 ± 0.3, < 0.001). Lowest quartile (<25 percentile) intake of oral sodium consumption (2.4 ± 0.5 g/day) was higher than WHO safe recommendation level of <2 g/day. Late afternoon spot urine sodium content was used to predict 24-h sodium excretion (6.1 ± 0.5 g/day), in turn population level sodium intake estimation. Analyzed sodium content of most frequently consumed all ready to eat foods was found to be higher than the reported values.
CONCLUSION
There is a strong need of evidence-based guidelines and policy formulation for national salt reduction program in India.
PubMed: 29899602
DOI: 10.4103/ijcm.IJCM_116_17 -
Clinical Ophthalmology (Auckland, N.Z.) 2016To evaluate short-term repeatability, intereye correlation, and effect of ocular dominance on macular pigment optical density (MPOD) measurements obtained using the...
PURPOSE
To evaluate short-term repeatability, intereye correlation, and effect of ocular dominance on macular pigment optical density (MPOD) measurements obtained using the QuantifEye Heterochromatic Flicker Photometer.
PATIENTS AND METHODS
A total of 72 study participants were enrolled in this prospective, cross-sectional study. Participants underwent a comprehensive ocular evaluation, including visual acuity, evaluation of ocular dominance, slit lamp examination, intraocular pressure measurement, and optic nerve head and macula analysis using optical coherence tomography and fundus photography. All study participants after initial training underwent MPOD measurement twice in both eyes in a randomized sequence. The repeatability was tested using Altman and Bland plots for first measurements with the second measurements for right eye and left eye and additionally by grouping eyes as a function of ocular dominance. The Pearson correlation coefficient was performed to assess the intereye correlation of MPOD values.
RESULTS
The mean age of study participants was 35.5 years (range 22-68 years). The mean MPOD measurements for OD (right eye) and OS (left eye) were 0.47 and 0.48, respectively, which followed a normal distribution (Shapiro-Wilk test, P=0.6 and 0.2). The 95% limits of agreement of Altman and Bland plots for the first and second measurements were -0.12 to +0.11 and -0.13 to +0.12 for OD and OS, respectively. The correlation coefficient of mean MPOD measurements of OD and OS was r statistic =0.94 (Pearson correlation coefficient P<0.0001; r (2) 0.89). The 95% limits of agreement of Altman and Bland plots when evaluated by laterality of eye or by ocular dominance were narrow, with limits of agreement ranging from -0.13 to +0.12.
CONCLUSION
The MPOD measurements obtained using the QuantifEye show good short-term repeatability. There is excellent intereye correlation, indicating that the MPOD values of one eye data can predict the fellow eye value with 89% accuracy. The ocular dominance had no bearing on the outcome of this psychophysical test in ocular healthy eyes.
PubMed: 27621586
DOI: 10.2147/OPTH.S111708 -
Clinical and Experimental Immunology Jun 1969A specially sensitive version of the Reichert microphotometer provides a means of obtaining accurate measurements of the emission of immunofluorescent microscopical...
A specially sensitive version of the Reichert microphotometer provides a means of obtaining accurate measurements of the emission of immunofluorescent microscopical preparations. The fluorescence of single particles down to 0·8 μ in diameter may be measured with all background excluded. The photometer has permitted determinations of titre of antisera, assessment of the validity of conventional visual estimation of fluorescence, and comparative studies of fluorescence intensity and fading under a variety of conditions. Preliminary studies by double immunofluorescent staining of two distinct antigenic constituents of cells which might be present either separately or together, suggest future value in investigations of cell differentiation and dedifferentiation.
Topics: Animals; Antigens; Fluorescent Antibody Technique; Humans; Liver; Methods; Photometry; Rats; Stomach
PubMed: 4891246
DOI: No ID Found -
Optics Express Jul 2018The General V(λ) Mismatch Index, f1 , was defined for a general description of the photometric performance of photometers. This index is widely-used in photometry, and...
The General V(λ) Mismatch Index, f1 , was defined for a general description of the photometric performance of photometers. This index is widely-used in photometry, and it is very relevant for selecting photometers for low-uncertainty photometric measurements. It quantifies the spectral mismatch between the relative spectral responsivity of a photometer and the luminous efficiency function for photopic vision, V(λ). The linear correlation between the real general photometric measurement error and f1 of 77 photometers was studied for four sets of light sources: R, G and B LEDs (narrowband spectral power distributions, SPDs), blackbodies at different colour temperatures (broadband SPDs), phosphor-based LEDs at different correlated color temperatures (SPDs with narrow- and broad-band features), and a mixture of blackbodies and phosphor-based LED sources. This article shows that it can be defined an alternative index which is notably better correlated with the real general photometric measurement error of the photometers under light sources with broadband features in their SPDs, adequate for general lighting. This index is based on filtering the high spectral frequencies variations between the relative spectral responsivity of the photometer and V(λ). The use of this new index for the assessment of the general photometric performance of photometers would improve the selection of high quality photometers and, consequently, would contribute to the general improvement of photometric measurements.
PubMed: 30114039
DOI: 10.1364/OE.26.018633 -
Aerosol Science and Technology : the... May 2018This article presents the development of a Portable Aerosol Collector and Spectrometer (PACS), an instrument designed to measure particle number, surface area, and mass...
This article presents the development of a Portable Aerosol Collector and Spectrometer (PACS), an instrument designed to measure particle number, surface area, and mass concentrations continuously and time-weighted mass concentration by composition from 10 nm to 10 μm. The PACS consists of a six-stage particle size selector, a valve system, a water condensation particle counter to detect number concentrations, and a photometer to detect mass concentrations. The stages of the selector include three impactor and two diffusion stages, which resolve particles by size and collect particles for later chemical analysis. Particle penetration by size was measured through each stage to determine actual collection performance and account for particle losses. The data inversion algorithm uses an adaptive grid-search process with a constrained linear least-square solver to fit a tri-modal (ultrafine, fine, and coarse), log-normal distribution to the input data (number and mass concentration exiting each stage). The measured 50% cutoff diameter of each stage was similar to the design. The pressure drop of each stage was sufficiently low to permit its operation with portable air pumps. Sensitivity studies were conducted to explore the influence of unknown particle density (range from 500 to 3,000 kg/m) and shape factor (range from 1.0 to 3.0) on algorithm output. Assuming standard density spheres, the aerosol size distributions fit well with a of -4.9% to 3.5%, of 3.3% to 27.6%, and values of 0.90 to 1.00. The fitted number and mass concentration biases were within ±10% regardless of uncertainties in density and shape. However, fitted surface area concentrations were more likely to be underestimated/overestimated due to the variation in particle density and shape. The PACS represents a novel way to simultaneously assess airborne aerosol composition and concentration by number, surface area, and mass over a wide size range.
PubMed: 37654799
DOI: 10.1080/02786826.2018.1524985