An Investigation of Lighting Levels and Sleep Quality

Sleep quality in young adults is compromised. Instead of the recommended 7 hours, young adults’ schedule interruptions disturb sleep to a typical six and a half hours, with common disturbances in falling asleep and staying asleep. Recent literature has identified an association between academic performance, negative mood state and low activity level in young adults with sleep disturbances. Young adulthood is a time for the installation of sleep health. Both individual and schedule impositions to the young adults’ sleep schedule are to be modified to obtain Sleep Health. Recent research has identified daytime light effects on sleep such as blue light from electronics as alerting and low level light for relaxation. The aim of this study was to identify sleep quality effects with varying light exposures. It was hypothesized that bright (>450 lux) light conditions would be considered focusing and low light (<220 lux) would be considered calming. We hypothesized that sleep quality would improve by 5% with the introduction of a calm light condition. Undergraduates from a small midwestern university were invited to participate in the study in exchange for a gift card. Six participants completed the study, two males, four females all between 21 - 24 years old. Both hypotheses were supported by qualitative analysis.

Effects of Light Quality on Growth and Physiological Characteristics of Neopyropia yezoensis Free Living Conchocelis

[Objectives]To study the differences of growth rate,morphology,ultrastructure,pigment content and antioxidant enzyme activity of free-living conchocelis of cultivated type of Neopyropia yezoensis under different light qualities(white,red,blue,and green light).[Methods]The study was carried out through light quality design and culture,growth rate determination,microstructure and ultrastructure observation,chlorophyll a content and carotenoid content determination,phycobiliprotein content determination,malondialdehyde(MDA)content determination,superoxide dismutase(SOD)activity determination.[Results]After 21 d of culture,the specific growth rate(SGR)and chlorophyll a content of free-living conchocelis of N.yezoensis were significantly increased by white light(WL),followed by red light(RL)and green light(GL),and they were the lowest under blue light(BL).Compared with the WL group,the BL group had the highest content of phycoerythrin(PE),and the RL and GL groups had the highest content of phycocyanin(PC).The algal body of WL group was normal black brown,and the cell wall was the thickest.In RL and GL groups,the algal bodies were green,and their diameters and cell wall thicknesses were similar to those in WL group.In BL group,the algal body was bright red,the diameter was the smallest,the cell wall was the thinnest,and the ultrastructure showed that the number of plastoglobulus on the thylakoid was the largest.After BL irradiation,the highest MDA content and the lowest SOD activity were observed.The results revealed that WL is the most beneficial to the growth of free-living conchocelis,followed by RL and GL,while BL has adverse effects.[Conclusions]This study explored the most suitable light quality conditions for the propagation of free-living conchocelis.It is expected to provide germplasm guarantee for the production and seedling of N.yezoensis.

基于CEEMDAN-VMD-TCN-lightGBM模型的水质预测研究

针对目前水质预测模型中因为数据本身的复杂性、在信号处理过程中存在的噪声干扰以及分解深度不够导致单一分解难以全面捕捉信号非线性特征的问题,提出了一种基于二次分解的水质预测模型。该模型采用完全自适应噪声集合经验模态分解(CEEMDAN)对原始数据进行分解,再利用变分模态分解(VMD)对熵值最高的模态分量进行二次分解,最终将处理后的时间序列输入到TCN-lightGBM多特征预测模型中。同时,采用麻雀算法(SSA)对预测模型进行优化。以山东省玉符河水质为例,本模型的均方根误差(RMSE)是0.1053,平均绝对误差(MAE)是0.0815,决定系数(R2)是0.9471,与GRU、LSTM、LightGBM、TCN等当下较为流行的模型的预测指标进行比较。结果显示,在R2上本模型提升了53.04%、70.41%、66.07%、65.20%等,在RMSE上减少了62.76%、65.50%、64.93%、64.80%等,在MAE上降低了62.76%、66.24%、63.80%、65.24%等。由此可知,基于CEEMDAN-VMD-TCN-lightGBM的模型具有更好的预测性能、泛化能力和捕捉信号非线性特征的能力。

Regulation of Reproduction in Delayed Gametophyte of Saccharina japonica (Laminariales, Phaeophyceae): Effects of Light Intensity, Quality and Photoperiod

Saccharina japonica gametophytes can survive a long period under unfavorable environmental conditions,while they also delay in growth and/or reproduction.Although the reproduction in delayed gametophyte of S.japonica was known to be strongly influenced by light intensity,light quality,and photoperiod,no previous studies have evaluated their interactive effects on gametogenesis.To evaluate these effects,we used an orthogonal experiment to expose delayed gametophytes of S.japonica to different light intensities,light qualities,and photoperiods for 12 days.The results showed that changes in light intensity rather than light quality and photoperiod significantly affected the relative growth rates of the delayed gametophytes.Blue light had the greatest promotion on reproduction rate.The optimal light conditions in the early vegetative growth phase in gametogenesis induction for the delayed gametophytes were at 60–80μmol photons m^(−2) s^(−1) with daylength of 12 or 16 hours under white or blue light.When the delayed gametophytes were maintained in a constant light condition from delayed state to gametogenesis,the beneficial photoperiods for vegetative growth and reproductive rate were both 16L(16 hours of light):8D(8 hours of dark).However,when the delayed S.japonica gametophytes achieve the optimal growth state during the first 6 days and then they were cultured at different light conditions for the following 6 days,the reproduction rate increased as the daylength decreased and attained a peak value in group of 8L:16D photoperiod,indicating that photoperiod adjustment at the transition period is crucial in the gametogenesis induction process of delayed gametophyte of S.japonica.

Effects of Variable Lighting Intensity on Growth Characteristics and Nutritional Quality of Hydroponically Grown Arugula(Eruca sativa Mill.)

Arugula(Eruca sativa Mill.),as an edible medicinal vegetable of peculiar flavor,is served as uncooked dish.The influence of variable lighting intensity(LI)on the growth characteristics and nutritional quality of hydroponically grown arugula was investigated by using light-emitting diodes(LEDs)to light the hydroponically grown arugula for a reference for industrialized arugula production.The dynamic demands of arugula for LI in the seedling stage,initial growth stage and vigorous growth stage were tested under two light quality conditions including a red/blue light ratio of 7:1 and a light/dark photoperiod of 12 h/12 h.Then,the curves of variable LI-induced changes in the growth indices of arugula in different development periods were drawn.Next,the influence of variable LI on the growth characteristics and nutritional quality of arugula was investigated by measuring the dry/fresh weight ratio,chlorophyll content,vitamin C content and soluble protein content.Variable LI significantly increased the height,stem diameter,leaf width,dry/fresh weight ratio,chlorophyll content and soluble protein content of arugula plant.Plant height,stem diameter,dry/fresh weight ratio,chlorophyll content and soluble protein content were the highest in the group exposed to LI of 200,300 and 300μmol•m^(-2)•s^(-1)during the seedling stage,initial growth stage and vigorous growth stage,respectively.The greatest leaf width was achieved at LI of 100,250 and 350μmol•m^(-2)•s^(-1),respectively.High intensity LI markedly repressed the synthesis of vitamin C.

Impact of Fluorescent Light Energy on the Quality of Life of Dogs with Dermatologic Disease and Their Owners

Background: Quality of life (QoL) is a term used to evaluate general well-being, and it is defined as ‘the degree to which an individual enjoys his or her life. Within the realm of medicine, the evaluation of QoL frequently involves examining how disease exerts a detrimental impact, diminishing the enjoyment and fulfilment experienced by the individual. Dermatological diseases have been found to exert a substantial negative influence on the QoL of dogs and their owners due to nuisance and stress related to the disease but also due to the caregiver burden. In the management of bacterial skin infections, topical therapy is commonly administered alongside systemic antibiotics. Nonetheless, the protracted duration of treatment and difficulties in ensuring owner compliance can introduce a significant caregiver burden, potentially exacerbating the challenges associated with these conditions. Purpose: This study aimed to evaluate the impact on the quality of life (QoL) of dogs with dermatologic diseases after fluorescent light energy (FLE) treatment. Methods: The study was an open, prospective, multicentric clinical trial that included dogs with various dermatological conditions. The dogs received FLE treatment once weekly until the clinical resolution was achieved. Owners completed a validated questionnaire to assess the QoL of their dogs before and after therapy. Results: Thirty-five dogs with deep pyoderma, interdigital furunculosis, pyotraumatic dermatitis, wounds and perianal fistulas were included. All dogs received two sessions of fluorescent light energy once a week. Median treatment duration was 9 weeks for perianal fistula, 7 weeks for interdigital furunculosis, 5 weeks for deep pyoderma, 3 weeks for wounds and 1.5 weeks for pyotraumatic dermatitis. Complete remission was noted in 86% of dogs, and 14% showed an improvement but partial remission. The majority of owners reported a positive impact on their dogs’ QoL after therapy, and 74% of the dogs showed at least a 50% reduction in QoL scores. Conclusion: Fluorescent light energy has been shown to exert beneficial effects on the healing of dermatological diseases and the quality of life (QoL) in dogs and their owners, whether used as a standalone treatment or in combination with standard care therapies. Additionally, it was well-tolerated by the dogs. This study emphasizes the significance of considering both the owner’s and dog’s QoL when evaluating the therapeutic efficacy of dermatological treatments.

特征提取及数据扩充的GA-LightGBM半导体质量检测方法

半导体质量检测数据具有的“相关性、冗余性、不平衡性”等特点,导致传统的分类算法效率较低,为此,提出一种基于特征提取及数据扩充的GA-LightGBM(genetic algorithm-light gradient boosting machine)质量检测方法。通过结合主成分分析(principal component analysis,PCA)、合成少数类过采样技术(synthetic minority oversampling technique,SMOTE)、遗传算法和LightGBM这4种方法,实现对产品质量的有效识别。实验结果表明,相较于传统分类算法,提出的方法可以有效提升质量检测的效率。

Effects of Different Light Qualities on Activity and Gene Expression of Caspase-like Proteases in Tobacco Leaves

[Objective] The study aimed to investigate the activity and gene expression of caspase-like proteases in tobacco leaves growing under different light qualities. [Method] By covering tobacco plants with white, red, yellow, blue and purple films to obtain different light quality, the changes of chlorophyll content, activity and gene expression of caspase-like proteases in the tobacco leaves were studied. [Results] Compared with treatments of white, red and yellow film, blue and purple films delayed the decrease of chlorophyll content and senescence of tobacco leaves at the late growth stage, and relatively lowered the activity and gene expression of caspase-like proteases during growth, development and senescence periods. [Conclusion] Different light qualities exhibited various effects on the growth, development and senescence of tobacco leaves, possibly by affecting the activity and gene expression of caspase-like proteases to some extent.

Light Quality-controlled Phytochemicals Biosynthesis in Vegetables and Fruits

Phytochemicals（including proteins, lipids, carbohydrates, vitamins, minerals,phenolic compounds and so on） are one of the most important groups of the bioactive compounds in vegetables and fruits, benefit for human health. The phytochemicals biosynthesis is affected by environmental factors, and light in particular. Light effects can be categorized in photoperiod, intensity and quality. While it is widely known that light intensity can positively affect phytochemicals accumulation, the effects of light quality are more complex and often reported with mixed results. So this review focuses on the currently knowledge about different light quality on the control of phytochemicals biosynthesis. A better knowledge on these regulatory mechanisms will be useful for modifying phytochemicals biosynthesis in vegetables and fruits.

Evaluation of Productivity and Light Quality in Two High Density Dwarf Rootstock Apple Orchards in Central China

[Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close planting of dwarf rootstock apples.[Method] The technical parameters of individual trees and group parameters as shoot number and composition and canopy coverage were determined, and the light quality in the canopy, fruit production and quality were investigated. [Result] Slender spindle （SS） orchard has 54 thousands shoots per 667 m^2. Coverage rate is 76%. Leaf area index is 1.9. The ratio of long, medium and spur shoots is 1：1：8. Fruit yield is 3 263 kg/667 m^2 with 85% first grade fruit. Light interception in the canopy is 58% while the ratio of canopy with good light is 65%. Modified slender spindle （MSS） orchard has 93 thousands shoots per 667 m^2 and the coverage is 77%. Leaf area index is 3.3. The ratio cf long, medium and spur shoots is 1：2：7. Fruit yield is 3 931 kg/667 m^2 with 85% first grade fruit. The light interception in the canopy is 73% while the ratio of canopy with good light is 35%. [Conclusion] Apple orchard with M26 dwarf rootstock trained as SS and MSS tree form in medium planting density may be useful to the management of the similar orchards in Central China.

Effects of Low Light on Agronomic and Physiological Characteristics of Rice Including Grain Yield and Quality

Light intensity is one of the most important environmental factors that determine the basic characteristics of rice development. However, continuously cloudy weather or rainfall, especially during the grain-filling stage, induces a significant loss in yield and results in poor grain quality. Stress caused by low light often creates severe meteorological disasters in some rice-growing regions worldwide. This review was based on our previous research and related research regarding the effects of low light on rice growth, yield and quality as well as the formation of grain, and mainly reviewed the physiological metabolism of rice plants, including characteristics of photosynthesis, activities of antioxidant enzymes in rice leaves and key enzymes involved in starch synthesis in grains, as well as the translocations of carbohydrate and nitrogen. These characteristics include various grain yield and rice quality components （milling and appearance as well as cooking, eating and nutritional qualities） under different rates of shading imposed at the vegetative or reproductive stages of rice plants. Furthermore, we discussed why grain yield and quality are reduced under the low light environment. Next, we summarized the need for future research that emphasizes methods can effectively improve rice grain yield and quality under low light stress. These research findings can provide a beneficial reference for rice cultivation management and breeding program in low light environments.

Effect of Light Quality on Photosynthesis and Chlorophyll Fluorescence in Strawberry Leaves

The photosynthetic characteristics of strawberry (Fragariaananassa Duch. cv. Toyonoka)leaves under illumination of identical light intensity(55-57% natural light) withdifferent light quality were studied. It was showed that the chlorophyll content,maximal photochemical efficiency of PSⅡ(Fv/Fm), Fm/Fo, amount of inactive PSⅡreactioncenters (Fi-Fo) and rate of QA reduction were positively correlated with the red-light/blue-light ratios, but the chlorophyll (a/b) ratios were negatively correlated withthem. Carotenoid content of the leaves was maximum under the blue film, than under greenfilm, red film, white film and yellow film, and negatively correlated with the red/far-red ratios. The apparent quantum yield (AQY), photorespiratory rate (Pr) and carboxylationefficiency (CE) were also strongly affected by light quality. The photosynthetic rate(Pn) in strawberry leaves under green film was significantly lower than under all otherfilm. Our results suggested that light quality is an essential factor regulating thedevelopment of PSⅡ, and phytochrome and an independent blue light photoreceptor,possibly a cryptochrome, can regulate photosynthetic performance.

Crop photosynthetic response to light quality and light intensity

Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production.

Relationships Between the Distribution of Relative Canopy Light Intensity and the Peach Yield and Quality

The aim of the present experiment was to study the relationship between the distribution of relative light intensity in canopy and yield and quality of Wanmi peach. The optimum relative canopy light intensity was judged to be 36.3% for high quality peaches, when canopy volumes of Wanmi peach trees with a relative light intensity 〈 30% accounted for 7.7 and 47.9% of the total canopy volume in June and September, respectively. The canopy volume with a relative light intensity 〉 80% was 27.7 and 3.1% of the total canopy volume in June and September, respectively. Peach canopies were divided into 0.5 m × 0.5 m × 0.5 m cubes, with the relative light intensity being measured at different positions of the canopy during the growing season. Yield and fruit quality were also measured at these positions at harvest. The results showed that the relative light intensity decreased gradually from outside to inside and from top to bottom of the tree canopy. Fruit were mainly distributed in the upper and middle portions of the canopy, 1.5-3.0 m above ground. Regression results showed that single fruit weight and soluble solid content were positively related to relative light intensity.

Systematic Identification of the Light-quality Responding Anthocyanin Synthesis-related Transcripts in Petunia Petals

Previous studies have shown that high light intensity can induce anthocyanin synthesis(AS)in petunia plants.To identifywhich kind of light quality plays a role in inducing such metabolic process,and what transcripts participate in controlling it,we carried out whole-transcriptome sequencing and analysis of petunia petals treated with different light-quality conditions.Among the red and white light treatments,a total of 2205 differentially expressed genes and 15,22,and 20 differentially expressed circRNAs,miRNAs,and lncRNAs,were identified respectively.The AS-related genes,including the structural genes CHSj,F3H,F35H,DFR,and ANS,and the regulatory genes AN4,DPL,PHZ and MYBx were found to be downregulated under red light condition compared with their levels under white light condition.Furthermore,the light photoreceptor Cryptochrome 3(CRY3)and a series of light-dependent genes,such as PIF,HY5,andBBXs,were also determined to respond to the light treatments.The anthocyanin contents in early petunia petals under red light were significantly lower than that under white and blue light.The results of qRT-PCR further confirmed the expression pattern of some AS-related and light-response genes in response to different light quality.Yeast two-hybrid results showed that the key elements in the light signal pathway,HY5 can interact with BBX19,BBX24 and BBX25.And PHZ,the important AS regulator can induce anthocyanin synthesis in response to blue light quality fromtransient expression analysis in petunia petals.These findings presented here not only deepen our understanding of how light quality controls anthocyanin synthesis,but also allow us to explore potential target genes for improving pigment production in petunia flower petals.

Low Light During Grain Filling Stage Deteriorates Rice Cooking Quality, but not Nutritional Value

To investigate the effect of low light （LL, 50% natural light） during grain filling （GF） stage on rice transamination, amino acid （AA） accumulation, nutritional value, and cooking quality in three different rice genotypes, transaminase activities and AA levels in grains during GF stage and the traits that significantly affected rice quality （physical appearance, cooking quality, and nutritional value） were analyzed. LL did not disturb transamination in rice grains during GF stage, as minimal impact was found on alanine and aspartate transaminase activities. Nevertheless, most AAs in caryopses, including lysine and threonine, increased in response to LL, except for sulfur-containing AAs. These results suggest that AA metabolism and accumulation in rice grains were rarely suppressed by LL during GF stage. Rice nutritional ingredients at harvest, such as major protein components including glutelin and most important essential amino acids （EAAs） including lysine and threonine, increased significantly in response to LL, whereas most protein and EAA ratios were rarely affected. However, LL markedly affected physical appearance of rice grains by reducing brown rice rate, milled rice rate, and 1000-grain weight and increasing the chalkiness rate. In addition, cooking qualities decreased in response to LL, while breakdown values and amylose levels decreased and setback values increased. We concluded that LL during GF stage decreased the cooking quality of rice, but could potentially improve the nutritional value of rice.

Light quality and temperature effects on antirrhinum growth and development

An experiment was carried out to examine the effects of light quality on the growth and development of antirrhinum under three different temperatures 19℃, 24℃ and 27℃ in glasshouses. Five different colour filters (i.e. 'Red absorbing', 'Blue absorbing', 'Blue and Red absorbing' and two 'partially Blue absorbing' materials) were tested, with one clear polythene as a control. Plant height, internode length and leaf area were significantly affected by the spectral filters as well as the temperature.Analysis of color filter's effect on presumed photoreceptors to exist indicated that antirrhinum plant height was regulated by the action of a blue acting photoreceptor (BAP) and not the phytochrome. There was no evidence for an effect ofphytochrome or BAP on time to flowering, however, increasing temperature levels effectively decreased the time to flowering. To predict the effects of different spectral qualities and temperature, simple models were created from data on plant height, internode length and time to flowering. These models were then applied to simulate the potential benefits of spectral filters and temperature in manipulation of growth control and flowering in antirrhinum.

Effects of light quality on growth rates and pigments of Chaetoceros gracilis(Bacillariophyceae)

Light is an important parameter in algal culturing.In this work,the effects of different light qualities on growth of the marine diatom Chaetoceros gracilis are evaluated.The cells were cultured under light quantum flux density of 60μmol photons/(m2·s)with nine light qualities:LED red light(LR),LED blue light(LB),LED red plus LED blue light(LR+LB),LED white light(LW),fluorescent white light(FW),and combinations of LW and FW lights with increased proportions of red or blue light(FW+LR,FW+LB,LW+LR,and LW+LB).Blue light promoted the growth of C.gracilis largely.Three light qualities,FW+LR,LW+LR,and LR,resulted in the lowest growth rate.Both chlorophyll and carotenoids reached the highest level under LB and the lowest level under LR among monochromatic light sources;however,increasing of the proportion of blue or red light in the white light induced an increase of the chlorophyll and carotenoid concentrations.Light absorption ability of microalgae was critical for the growth of these organisms,as we observed a positive correlation between the extinction coefficient at different wavelengths and the specific growth rate.These findings are of importance to improve the culturing of this alga in bioreactors.

Effects of Light Quality on Carbon and Nitrogen Assimilation and Root Activity of Eggplant

[Objective] This study was conducted to provide theoretical and data reference for high-quality high-yield production of Shangqie 1 under controlled light quality environment and light quality control of other eggplant varieties. [Method] With Shangqie1 as an experiment material, the effects of red light, blue light, red-blue light, red-blue light and white light(control) on the carbon-nitrogen metabolism and root vitality of eggplant were investigated. [Result] Different light quality significantly affected sugar and starch contents in leaves of eggplant. Under the red-blue light(5∶1) treatment, the sucrose, total sugar and starch contents were the highest, and the values were higher than those under the white light treatment by 3.47%, 13.61% and 33.49%,respectively. The fructose content was the highest under white light. Under red-blue light(3∶1) and red-blue light(5∶1), the nitrate nitrogen contents were higher than that under white light, indicating that compound light affects nitrate content not only by simple superposition of light quality, but also by other type of interaction effect. The free amino acid and soluble protein contents under blue, red-blue(3∶1), red-blue(5∶1) and red light treatments were all higher than those under the white light treatment, and the blue light treatment exhibited the highest values, which were higher than those under white light by 24.89% and 46.62%, respectively, with significant differences. The red-blue light(5 ∶1) treatment exhibited the highest root vitality of eggplant, which was higher than that under the white light treatment by 31.85%. The red light treatment had the second highest root vitality, which was higher than that under the white light treatment by 19.30%, followed by the red-blue light(5∶1) treatment, and the blue light treatment showed the lowest value. [Conclusion] Under red-blue light(5 ∶1) treatment, eggplant had vigorous carbon-nitrogen metabolism and the highest root vitality.

Monitoring Flue-Cured Tobacco Leaf Chlorophyll Content under Different Light Qualities by Hyperspectral Reflectance

Rapid assessment of foliar chlorophyll content in tobacco is critical for assessment of growth and precise management to improve quality and yield while minimizing adverse environmental impact. Our objective is to develop a precise agricultural practice predicting tobacco-leaf chlorophyll-a content. Reflectance experiments have been conducted on flue-cured tobacco over 3 consecutive years under different light quality. Leaf hyperspectral reflectance and chlorophyll-a content data have been collected at 15-day intervals from 30 days after transplant until harvesting. We identified the central band that is sensitive to tobacco-leaf chlorophyll-a content and the optimum wavelength combinations for establishing new spectral indices (simple ratio index, RVI;normalized difference vegetation index, NDVI;and simple difference vegetation index, DVI). We then established linear and BackPropagation (BP) neural network models to estimate chlorophyll-a content. The central bands for leaf chlorophyll-a content are concentrated in the visible range (410 - 680 nm) in combination with the shortwave infrared range (1900 - 2400 nm). The optimum spectral range for the spectral band combinations RVI, NDVI, and DVI are 440 and 470 nm, 440 and 470 nm, and 440 and 460 nm, respectively. The linear RVI, NDVI, and DVI models, SMLR model and the BP neural network model have respective R2 values of 0.76, 0.77, 0.69, 0.78 and 0.86, and root mean square error values of 0.63, 1.60, 1.59, 2.04 and 0.05 mg chlorophyll-a/g (fresh weight), respectively. Our results identified chlorophyll-a sensitive spectral regions and new indices facilitate a rapid, non-destructive field estimation of leaf chlorophyll-a content for tobacco.