Diurnal Temperature Difference Research Articles

Effects of photoperiod on the growth and physiological responses in Ulva prolifera under constant and diurnal temperature difference conditions

Photoperiod and temperature are two main factors in the growth of macroalgae, and changes in photoperiod and diurnal temperature difference exist in natural condition. In order to study the effects of photoperiod and diurnal temperature difference on the growth of green algae Ulva prolifera, we cultured this species under three light/dark cycles (light: dark = 10:14, 12:12 and 16:08) with constant (22 °C for light and dark period, noted as 22-22 °C) and diurnal temperature difference (22 °C and 16 °C for light and dark period, respectively, noted as 22-16 °C) conditions. The results showed that: 1) Compared with 10:14 light/dark cycle, the growth of U. prolifera under 12:12 light/dark cycle was significantly enhanced by 39% and 16% for 22-22 °C and 22-16 °C treatments, respectively, while the increase proportion decreased when the daylength increase from 12 h to 16 h. 2) The enhancement in growth induced by diurnal temperature difference was observed under 10:14 light/dark cycle, but not for 12:12 and 16:08 light/dark cycle treatments. 3) The Chl a content and photosynthetic rate increased under short light period and 22-22 °C conditions, while under 22-16 °C conditions, higher photosynthetic rate was observed under 12:12 light/dark cycle and no significant difference in Chl a content was observed. 4) Under 22-22 °C conditions, compared with 10:14 (L:D) treatment, the expression levels of proteins in light-harvesting complexes, PSII and carbon fixation were down regulated, while the photorespiration and pentose phosphate pathway (PPP) were up regulated by 16:08 light dark cycle. Then we speculate that the higher photosynthetic rate may be one compensation mechanism in short photoperiod, and under long light period condition the up regulations of photorespiration and PPP can be in charge of the decrease in enhancement growth induced by longer daylength.

Transcriptomic Analysis for Diurnal Temperature Differences Reveals Gene-Regulation-Network Response to Accumulation of Bioactive Ingredients of Protocorm-like Bodies in Dendrobium officinale.

Dendrobium officinale Kimura et Migo (D. officinale) is one of the most important traditional Chinese medicinal herbs, celebrated for its abundant bioactive ingredients. This study demonstrated that the diurnal temperature difference (DIF) (T1: 13/13 °C, T2: 25/13 °C, and T3: 25/25 °C) was more favorable for high chlorophyll, increased polysaccharide, and total flavonoid contents compared to constant temperature treatments in D. officinale PLBs. The transcriptome analysis revealed 4251, 4404, and 4536 differentially expressed genes (DEGs) in three different comparisons (A: 25/13 °C vs. 13/13 °C, B: 13/13 °C vs. 25/25 °C, and C: 25/13 °C vs. 25/25 °C, respectively). The corresponding up-/down-regulated DEGs were 1562/2689, 2825/1579, and 2310/2226, respectively. GO and KEGG enrichment analyses of DEGs showed that the pathways of biosynthesis of secondary metabolites, carotenoid biosynthesis, and flavonoid biosynthesis were enriched in the top 20; further analysis of the sugar- and flavonol-metabolism pathways in D. officinale PLBs revealed that the DIF led to a differential gene expression in the enzymes linked to sugar metabolism, as well as to flavonol metabolism. Certain key metabolic genes related to ingredient accumulation were identified, including those involved in polysaccharide metabolism (SUS, SUT, HKL1, HGL, AMY1, and SS3) and flavonol (UGT73C and UGT73D) metabolism. Therefore, these findings indicated that these genes may play an important role in the regulatory network of the DIF in the functional metabolites of D. officinale PLBs. In a MapMan annotation of abiotic stress pathways, the DEGs with significant changes in their expression levels were mainly concentrated in the heat-stress pathways, including heat-shock proteins (HSPs) and heat-shock transcription factors (HSFs). In particular, the expression levels of HSP18.2, HSP70, and HSF1 were significantly increased under DIF treatment, which suggested that HSF1, HSP70 and HSP18.2 may respond to the DIF. In addition, they can be used as candidate genes to study the effect of the DIF on the PLBs of D. officinale. The results of our qPCR analysis are consistent with those of the transcriptome-expression analysis, indicating the reliability of the sequencing. The results of this study revealed the transcriptome mechanism of the DIF on the accumulation of the functional metabolic components of D. officinale. Furthermore, they also provide an important theoretical basis for improving the quality of D. officinale via the DIF in production.

Interaction between air pollutants and meteorological factors on pulmonary tuberculosis in northwest China: A case study of eight districts in Urumqi.

Meteorological factors and air pollutants are associated with the spread of pulmonary tuberculosis (PTB), but few studies have examined the effects of their interactions on PTB. Therefore, this study investigated the impact of meteorological factors and air pollutants and their interactions on the risk of PTB in Urumqi, a city with a high prevalence of PTB and a high level of air pollution. The number of new PTB cases in eight districts of Urumqi from 2014 to 2019 was collected, along with data on meteorological factors and air pollutants for the same period. A generalized additive model was applied to explore the effects of meteorological factors and air pollutants and their interactions on the risk of PTB incidence. Segmented linear regression was used to estimate the nonlinear characteristics of the impact of meteorological factors on PTB. During 2014-2019, a total of 14,402 new cases of PTB were reported in eight districts, with March to May being the months of high PTB incidence. The exposure-response curves for temperature (Temp), relative humidity (RH), wind speed (WS), air pressure (AP), and diurnal temperature difference (DTR) were generally inverted "U" shaped, with the corresponding threshold values of - 5.411 °C, 52.118%, 3.513m/s, 1021.625hPa, and 8.161 °C, respectively. The effects of air pollutants on PTB were linear and lagged. All air pollutants were positively associated with PTB, except for O3, which was not associated with PTB, and the ER values for the effects on PTB were as follows: 0.931 (0.255, 1.612) for PM2.5, 1.028 (0.301, 1.760) for PM10, 5.061 (0.387, 9.952) for SO2, 2.830 (0.512, 5.200) for NO2, and 5.789 (1.508, 10.251) for CO. Meteorological factors and air pollutants have an interactive effect on PTB. The risk of PTB incidence was higher when in high Temp-high air pollutant, high RH-high air pollutant, high WS-high air pollutant, lowAP-high air pollutant, and high DTR-high air pollutant. In conclusion, both meteorological and pollutant factors had an influence on PTB, and the influence on PTB may have an interaction.

Amine-functionalized MIL-101(Cr) fibers for direct air capture at cold temperatures using rapid temperature vacuum swing adsorption

Given that most of the world shows annual temperatures lower than 25 °C and some regions exhibit a large diurnal temperature difference in a single day, it is desirable to explore the CO2 sorption behavior of materials not only at ambient (25 °C) but also at cooler, “sub-ambient” conditions (defined here as < 25 °C). These cold temperatures may offer advantages for DAC such as higher gas adsorption capacities and lower absolute humidity, reducing concomitant water adsorption. Here, amine-functionalized MIL-101(Cr) fibers are evaluated at cold temperatures using rapid temperature vacuum swing adsorption (RTVSA). MIL-101(Cr)/cellulose acetate fibers loaded with macromolecular amines are evaluated as practical gas–solid contactors. As spun MIL-101(Cr) fibers show desirable properties for use as structured contactors such as high permeance and low pressure drop. Breakthrough and RTVSA experiments are conducted in the presence of humidity at sub-ambient temperatures to understand the CO2 adsorption and desorption behavior of the sorbent/contactor under conditions approaching practical operation. With optimized amine loading, the PEI-MIL-101(Cr) fibers give CO2 capacities comparable to the powder form of the sorbent, as well as sharp breakthrough curves at fast flow rates (1.4 m/s superficial velocity) suggesting the system is not limited by additional mass transfer resistances under the tested conditions. RTVSA shows fast desorption kinetics (14.4 mmol of CO2/g of fiber/h) at moderate desorption conditions, at 0.1 bar vacuum with temperatures below 80 °C. The entire cycle during RTVSA finishes in ∼ 25 min with ∼ 76 mol% CO2 purity as the product in this initial, modestly optimized study.

Analysis of the association between diurnal temperature difference and relative humidity and myocardial infarction in Shantou residents

Objective: To analyze the effect of meteorological conditions on mortality and population susceptibility of patients with acute myocardial infarction (AMI) in the Shantou area and to provide a scientific basis for the local public health system to prevent AMI. Methods: The AMI mortality data recorded in the resident cause of death surveillance database of Shantou from January 1, 2015, to December 31, 2020, were collected and the distribution lag nonlinear model was used to analyze the diurnal temperature range (DTR) and relative humidity (RH) on AMI mortality and the lag effect. Results: There were 13 932 deaths due to AMI in Shantou during the study period, with a male-to-female sex ratio of 1.3∶1. There was a significant association between high diurnal temperature difference exposure and low RH exposure and AMI deaths, with both single-day lag effects appearing and reaching a maximum at lag 2 day (RR=1.019, 95%CI: 1.000-1.039; RR=1.018, 95%CI: 1.003-1.034); the cumulative lag effect was all maximal at lag 0-14 day (RR=1.199, 95%CI: 1.025-1.401; RR=1.279, 95%CI: 1.117-1.465). The elderly (≥75 years) and female populations were susceptible to high DTR exposure and low RH exposure conditions. Conclusions: There was a significant association between DTR and RH and mortality of AMI in Shantou with a significant lag in their effects. Both female and elderly populations ≥75 years old were susceptible populations under high DTR and low RH exposure conditions.

Decoupling the response of vegetation dynamics to asymmetric warming over the Qinghai-Tibet plateau from 2001 to 2020

Global land surface air temperature data show that in the past 50 years, the rate of nighttime warming has been much faster than that of daytime, with the minimum daily temperature (Tmin) increasing about 40% faster than the maximum daily temperature (Tmax), resulting in a decreased diurnal temperature difference. The Qinghai-Tibet Plateau (QTP) is known as the "roof of the world", where temperatures have risen twice as fast as the global average warming rate in the last few decades. The factors affecting vegetation growth on the QTP are complex and still not fully understood to some extent. Previous studies paid less attention to the explanations of the complicated interactions and pathways between elements that influence vegetation growth, such as climate (especially asymmetric warming) and topography. In this study, we characterized the spatial and temporal trends of vegetation coverage and investigated the response of vegetation dynamics to asymmetric warming and topography in the QTP during 2001–2020 using trend analysis, partial correlation analysis, and partial least squares structural equation model (PLS-SEM) analysis. We found that from 2001 to 2020, the entire QTP demonstrated a greening trend in the growing season (April to October) at a rate of 0.0006/a (p < 0.05). The spatial distribution pattern of partial correlation between NDVI and Tmax differed from that of NDVI and Tmin. PLS-SEM results indicated that asymmetric warming (both Tmax and Tmin) had a consistent effect on vegetation development by directly promoting greening in the QTP, with NDVI values being more sensitive to Tmin, while topographic factors, especially elevation, mainly played an indirect role in influencing vegetation growth by affecting climate change. This study offers new insights into how vegetation responds to asymmetric warming and references for local ecological preservation.

Experimental investigation into effects of lignin on sandy loess

Promoted by the international Helin Airplane project where sandy loess is widely distributed, this study investigates the feasibility of improving the mechanical properties of sandy loess by using lignin, an environmentally friendly material. Considering the climatic conditions in the distribution area of sandy loess, such as strong evaporation and large diurnal temperature difference, extensive experiments including curing test, wet-dry cycle test, freeze–thaw cycle test, triaxial test, XRD test and SEM test are conducted to determine the strengthening effect of lignin on sandy loess. Test results show that 21 days are enough for lignin-modified sandy loess to complete curing and obtain maximum compressive strength, which increases with the increase of lignin content. Lignin has insignificant effect on the resistance of sandy loess to wet-dry cycles, but it can significantly improve the resistance to freeze–thaw cycles. Lignin causes significant alterations on the stress–strain relationship and mechanical response of sandy loess by mainly changing the cohesion while maintaining the frictional angle unchanged. SEM results show that lignin gradually plays the role of cementation, bonding, and fiber reinforcement with increasing content, and it mainly affects fine-grained soils while it has less effect on large particles. Good agreement between different experiments is obtained.

Rubber latex yield is affected by interactions between antecedent temperature, rubber phenology, and powdery mildew disease.

Rubber (Hevea brasiliensis) latex production is crucial to the local economy, yet Xishuangbanna's climate is considered sub-optimal for rubber cultivation. The prevalence of the powdery mildew disease (Oidium heveae) in this region has decreased the annual latex yield by 20%. Rubber latex yield is influenced by several factors, including temperature, disease, other biotic conditions, and plantation management. However, the interrelationships and potential influencing networks between rubber latex yield and these factors are rarely quantitatively assessed, and understanding their impacts on latex yield could inform better management practices. To address this gap, we investigated the effects of temperature, phenology, and powdery mildew disease on rubber latex yield in March using observational data on daily rubber latex yield combined with detailed phenology, powdery mildew, and temperature data from 2004 to 2010 in a state farm in the Xishuangbanna, Yunnan, China. We found that the critical influencing periods of daily temperature difference (or diurnal temperature difference) on the rubber latex yield were during Nov 27-Jan 19 and Jan 21-Mar 17. Partial least square regression analysis and variance partitioning analysis were conducted on the 35 phenological variables, eight powdery mildew-related variables, and two climatic variables. The most influential factors were identified as the factors of the daily temperature differences during Jan-Mar, the duration of leaf flushing phenology, and mean and maximum percentage of leaves infected by powdery mildew. Subsequent canonical correlation analysis and linear regression found that temperature difference directly affected the rubber latex yield and indirectly affected the yield through phenology and powdery mildew disease. Raised daily temperature differences from Jan to Mar had the greatest impact, leading to a higher rubber latex yield. Our comprehensive quantitative assessment revealed the relative importance of antecedent daily temperature differences, phenology, and powdery mildew disease as well as their complex interconnections in influencing rubber latex yield. Our findings are essential tofuture studies on both powdery mildew disease and rubber latex yield, and alsodevelop rubber latex models.

First Report of leaf spot on Cucumber Caused by Pantoea ananatis in Hainan of China.

Cucumber (Cucumis sativus L.) is one of the most important vegetables cultivated in the world. It is widely cultivated and mostly grown under greenhouse conditions (Sallam et al. 2021). Cucumber has a long growth cycle and is particularly susceptible to bacterial diseases. In May 2021, bacterial leaf spot was found on cucumbers of the variety Lyuyou NO.3 in Hainan Province, China. In the early stage of the disease, the leaves showed small yellow-brown spots in the shape of water stains. When exposed to light, a yellow halo around the disease spots could be seen. In later stages, the lesions gradually become larger and more yellow. The leaf veins around the disease site also gradually turned yellow (Figure 2a). In serious cases, the whole leaf turned yellow, resulting in leaf death. We collected plants with the same symptoms from 25 different farms in Hainan Province. Five plants were selected from each farm by the classic five-point sampling method and three leaves were selected from each plant, for a total of 15 leaves collected from each farm. Then three leaves were randomly selected from the 15 leaves on each farm for isolation of the pathogen, and a total of 75 leaves were isolated. We found that the incidence of the disease was from 20% to 30% based on a diagnostic test, which conducted on 75 cucumber leaves samples suspected of same symptom of cucumber, collected from Hainan Province. Using microscopy, bacterial streaming was observed to tentatively identify the causal agent as a bacteria. Tissue isolation was used to isolate the responsible pathogens. A 5 mm × 5 mm sample of tissue at the junction of diseased and healthy sections was collected. First, the surface of the tissue was disinfected in a 75% ethanol solution for 30 sec; then it was soaked in 2% NaOCl for 5-7 min, and finally, it was washed thrice in sterile distilled water. The tissues were inoculated onto lysogen broth culture media (LB) and cultured in a 28℃ incubator for 2 days. Bacterial colonies that emerged from the tissues were cultured in LB. Four isolated colonies were selected for verification. The colonies of isolated from the diseased leaves of cucumber are round, egg yellow and slightly sticky (Figure 2c). The isolate named PA-1 was identified by PCR amplification and sequencing of the partial 16S rRNA gene with the primer 27F/1492R (Lane 1991) and gyrB gene (Li et al. 2019). Sequences were stored in GenBank with the accession numbers OK576932.1 (16S rRNA, PA-1) and OL978577 (gyrB); BLASTn was used to compare these with other GenBank sequences. Sequencing of the 16S rRNA gene showed that PA-1 had a sequence length of 1403bp, with 99.78% genetic similarity to Pantoea ananatis strain MZ007857.1. Sequencing of the gyrB gene showed that the sequence length of PA-1 was 1136bp, with 99.29% genetic similarity to P. ananatis strain MW981331.1. Then, a pathogenicity text was conducted to verify Koch's postulates, which was done by first inoculating P. ananatis into LB liquid medium (shake culture at 28°C, 180 r/min). The log phase cell was collected by centrifugation (5,000 r/min for 2 min at 4°C), and inoculated strains were resuspended in sterile water at OD600 = 0.5. The bacterial suspension was inoculated on healthy cucumber leaves with a syringe. The control was sterile water, which was injected onto healthy cucumber leaves using the same methodology. The plants were placed in a greenhouse with a diurnal temperature difference of 21- 27°C and were observed daily. After two weeks, all bacterial inoculated plants developed symptoms of shriveling and necrosis (Figure 2b), while the control group showed no symptoms. From the symptomatic plants, the pathogen was isolated again and identified by morphological and molecular characterization. The sequences of the isolates recovered from the inoculated experiment matched 100% the sequences of the isolate PA-1. Koch's postulates were completed by following the previously described method. To our knowledge, this is the first report of P. ananatis causing leaf spot of cucumber.

Biomass production and astaxanthin accumulation of Haematococcus pluvialis in large-scale outdoor culture based on year-round survey: Influencing factors and physiological response

Astaxanthin is an economically valuable carotenoid pigment, and most natural astaxanthin is produced via the large-scale cultivation of the green alga Haematococcus pluvialis in outdoor culture systems. The effects of various environmental factors on Haematococcus and the physiological response of algal cells have rarely been investigated at commercial production scale, which are important for maximizing the yield and efficiency of algae production. This study found that the light intensity and cumulative light intensity are the most important factors affecting the biomass production and astaxanthin accumulation in outdoor large-scale cultivation of Haematococcus based on a year-round survey, and the cumulative light intensity between 550 and 850 mol photons·m−2 was an optimal range for a reasonable productive harvest. The temperature, diurnal temperature difference, culture period and initial inoculation concentration were found to be associated with production performance. Light requirements for green cell growth and for astaxanthin accumulation of immotile cells were quite different, the late showed a very high tolerance to light intensity. Under high light intensity or low temperature, non-photochemical quenching seemed to play a role in quenching excess energy in red immotile spore cells. This study provided detailed information on Haematococcus biomass production and astaxanthin accumulation at big commercial scale via tubular photobioreactors, which is valuable for improvement of commercial production of Haematococcus.

Enhancement of growth in Ulva prolifera by diurnal temperature difference combined with nitrogen enrichment

Many studies have documented the responses of Ulva prolifera to environmental factors. However, the diurnal temperature differences and interactive effects of eutrophication are usually ignored. In this study, we selected U. prolifera as material to examine the effects of diurnal temperature on growth, photosynthesis and primary metabolites under two nitrogen levels. We cultured U. prolifera seedlings under two temperature conditions (22-22 °C: 22 °C during day and night; 22-18 °C: 22 °C during day and 18 °C at night) and two nitrogen levels (LN: 0.1235 mg L−1; HN: and 0.6 mg L−1). The results showed that 1) HN-grown thalli had higher growth rates, the chlorophyll a (Chl a) content, photosynthesis, superoxide dismutase (SOD) activity, soluble sugar, and protein contents under the two temperature conditions; 2) The growth of thalli was enhanced by 22–18 °C condition compared with 22-22 °C, but the increase was only significant under HN condition; 3) 22-18°C-grown thalli had a lower net photosynthetic rate, maximal quantum yield (Fv/Fm), and dark respiration rate (Rd) than those grown at 22-22 °C; 4) No significant effects of diurnal temperature difference were detected on the SOD activity and soluble sugar content under LN and HN conditions, while the soluble protein content was enhanced by 22–18 °C under LN condition; 5) The nitrogen affected metabolite variations in U. prolifera more significantly than the diurnal temperature difference. The metabolite levels in the tricarboxylic acid cycle, amino acid, phospholipids, pyrimidine, and purine metabolism pathways increased under HN condition. The levels of glutamine, γ-aminobutyrate (GABA), 1-aminocyclopropane-1-carboxylate (ACC), glutamic acid, citrulline, glucose, sucrose, stachyose, and maltotriose were enhanced by 22–18 °C, especially under HN condition. These results identify the potential role of the diurnal temperature difference and offer new insight into the molecular mechanisms for U. prolifera responses to eutrophication and temperature.

Ecological niche shifts affect the potential invasive risk of Phytolacca americana (Phytolaccaceae) in China

BackgroundPredicting the potential habitat of Phytolacca americana, a high-risk invasive species, can help provide a scientific basis for its quarantine and control strategies. Using the optimized MaxEnt model, we applied the latest climate data, CMIP6, to predict the distribution of potential risk zones and their change patterns for P. americana under current and future (SSP126, SSP245, SSP585) climate conditions, followed by invasion potential analysis.ResultsThe predictions of MaxEnt model based on R language optimization were highly accurate. A significantly high area of 0.8703 was observed for working characteristic curve (AUC value) of subject and the kappa value was 0.8074. Under the current climate conditions, the risk zones for P. americana were mainly distributed in Sichuan, Chongqing, Guizhou, Hunan, and Guangxi provinces. The contribution rate of each climatic factor of P. americana was calculated using the jackknife test. The four factors with the highest contribution rate included minimum temperature of coldest month (bio6, 51.4%), the monthly mean diurnal temperature difference (bio2, 27.9%), precipitation of the driest quarter (bio17, 4.9%), and the warmest seasonal precipitation (bio12, 4.3%).ConclusionUnder future climatic conditions, the change in the habitat pattern of P. americana generally showed a migration toward the Yangtze River Delta region and the southeastern coastal region of China. This migration exhibited an expansion trend, highlighting the strong future invasiveness of the species. Based on the predictions, targeted prevention and control strategies for areas with significant changes in P. americana were developed. Therefore, this study emphasizes the need of an integrated approach to effectively prevent the further spread of invasive plants.

Design of an all-weather water extraction system based on solar energy and diurnal temperature difference

According to the survey, the water content in the air is as high as 14,000 km3. To make full use of the moisture retained in the air, we designed this all-weather water extraction system based on solar energy and the temperature difference between day and night. The system uses solar power panels to supply power to the micro-suction fan during the daytime, builds a condensation structure of “air-ground”, and uses the natural temperature difference between day and night to condense water at night and store it in the buried water reservoir. Semi-arid areas have water demand and have the advantages of all-weather use, fast water extraction, low cost, and ease of promotion.

Environmental Factors in Northern Italy and Sickle Cell Disease Acute Complications: A Multicentric Study.

Background: Environmental factors seem to influence clinical manifestations of sickle cell disease (SCD), but few studies have shown consistent findings. We conducted a retrospective multicentric observational study to investigate the influence of environmental parameters on hospitalization for vaso-occlusive crises (VOC) or acute chest syndrome (ACS) in children with SCD. Methods: Hospital admissions were correlated with daily meteorological and air-quality data obtained from Environmental Regional Agencies in the period 2011–2015. The effect of different parameters was assessed on the day preceding the crisis up to ten days before. Statistical analysis was performed using a quasi-likelihood Poisson regression in a generalized linear model. Results: The risk of hospitalization was increased for low maximum temperature, low minimum relative humidity, and low atmospheric pressure and weakly for mean wind speed. The diurnal temperature range and temperature difference between two consecutive days were determined to be important causes of hospitalization. For air quality parameters, we found a correlation only for high levels of ozone and for low values at the tail corresponding to the lowest concentration of this pollutant. Conclusions: Temperature, atmospheric pressure, humidity and ozone levels influence acute complications of SCD. Patients’ education and the knowledge of the modes of actions of these factors could reduce hospitalizations.

BDS/GPS deformation analysis of a long-span cable-stayed bridge based on colored noise filtering

Combining GPS and BDS technology to monitor the deformation of long-span railway bridges with stricter deformation control requirements is of significance to the safety and control of the bridge and the safety of railway traffic. Previous studies have ignored the influence of coloured noise in the deformation time series. This is not conducive to accurate deformation analysis of long-span railway bridges. Therefore, GPS, BDS and GPS/BDS monitoring data of Ganjiang Bridge located in Ganzhou city, Jiangxi Province, China are adopted in this paper to filter the coloured noise in the deformation time series by principal component analysis (PCA), and the influence of coloured noise on the deformation analysis results of railway bridge is analysed. The experimental results show that the diurnal temperature difference causes the mid-span and the tower of the railway cable-stayed bridge to deform with a period of about one day in the vertical and longitudinal directions, respectively. Ignoring colored noise will make the uncertainty of the deformation parameter estimation overly optimistic. PCA can significantly reduce the coloured noise, and thus reduce the uncertainty of deformation parameter estimation by about 73%. Moreover, the average difference between the daily periodic motion amplitudes of the monitoring points obtained by using GPS and BDS deformation time series is 1.65 mm. The use of GPS/BDS deformation time series is not only helpful to reduce the influence of coloured noise, but also can reduce the difference between amplitude analysis results obtained from GPS and BDS deformation time series.

Effect of gibberellic acid treatment and alternating temperature on breaking physiological dormancy and germination inPenthorum chinensePursh (Penthoraceae)

Penthorum chinense(Penthoraceae) is a threatened South Korean medicinal plant used to treat alcohol-related diseases and prepare cosmetics in traditional Chinese medicine. Wetlands, the native habitat of this plant, have been decreasing owing to damage caused by landisation and urban development in recent years. In this study, we considered the effect of temperature and gibberellic acid treatment onP. chinenseseed germination to improve conservation outcomes of the species. The optimum germination temperature was investigated using constant and alternating temperature treatments (60 conditions). In addition, gibberellic acid (GA3) treatment was performed to overcome physiological dormancy. We determined the germination (GP, %) and the number of days to reach 50% maximum germination (T50). The optimum temperature regime was 7°C / 23°C: GP was 95%, and T50was 15 days. The GA3treatment increased the GP ofP. chinenseseeds from 28 to 94% and decreased the T50value from 14.6 to 6.3 days at concentrations above 40 mg L–1. After the GA3treatment, the growth of radicles was delayed or inhibited. For the germination ofP. chinenseseeds, a diurnal temperature difference of ≥ 15°C is required.

Light Intensity-A Key Factor Affecting Flavonoid Content and Expression of Key Enzyme Genes of Flavonoid Synthesis in Tartary Buckwheat.

Tartary buckwheat, a polygonaceae family plant, is rich in abundant flavonoids, high-quality protein, and well-balanced essential amino acids. This study aimed to investigate the effects of climatic variables on the quality of Tartary buckwheat. In this study, six distinct types of Tartary buckwheat collected from the Sichuan Basin, Western Sichuan Plateau, and Yunnan-Guizhou Plateau in southwest China were chosen to investigate the impact of climatic conditions from the grain-filling stage to the harvest stage on the concentration of flavonoids and expression of key enzyme genes involved the synthesis of flavonoids. Meteorological data of three producing areas were collected from the China Meteorological Network, mainly including maximum temperature (Tmax), minimum temperature (Tmin), diurnal temperature difference (Tdif), and light intensity. Then, the contents of rutin, kaempferol-3-O-rutin glycoside, quercetin, and kaempferol in 30 batches of Tartary buckwheat from 6 varieties including Chuanqiao No. 1, Chuanqiao No. 2, Xiqiao No. 1, Xiqiao No. 2, Miqiao No. 1 and Di ku were determined by ultra performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Furthermore, the expression levels of phenylalanine ammonia lyase (PAL), 4-coumaric acid coenzyme A ligase (4CL), and anthocyanin synthase (ANS) in six kinds of Tartary buckwheat were detected by real-time polymerase chain reaction (PCR). The seed photos were processed by ImageJ processing software. The partial least squares method was used to analyze the correlation. As a result, light intensity can promote the accumulation of flavonoids and the expression of key enzyme genes. Miqiao No. 1, which grows in Liangshan Prefecture, Sichuan Province, has the highest light intensity and is the dominant variety with flavonoid content. More importantly, the expression levels of PAL and 4CL in the secondary metabolic pathway of flavonoids were positively correlated with the content of Tartary buckwheat flavonoids. Interestingly, the expression level of ANS was negatively correlated with the content of PAL, 4CL, and flavonoids. In addition, ANS is a key gene affecting the seed coat color of Tartary buckwheat. The higher the expression of ANS, the darker the seed coat color. These findings provide a theoretical basis and reference for the breeding of fine buckwheat varieties.

Evaluation of old building processes in the housing of Algeria’s arid regions and its improvement by integration of passive downdraught evaporative cooling

The objective of this study is the thermal evaluation and improvement of summer comfort of a dwelling in the arid climate of the In Saleh region in southern Algeria. An experimental study was conducted to assess the impact of old constructive processes on summer thermal comfort. The experimental tests have shown that a diurnal temperature difference of 8 °C can be reached during the overheating periods. Moreover, summer comfort is not achieved, the need to adapt a passive cooling system is very necessary. This study also aims to improve the hygrothermal comfort of the dwelling under study by adapting passive downdraught cooling system with water spraying to the climatic conditions of the arid region of In Saleh. to this end a theoretical parametric approach was performed using a mathematical model reported in the literature to adapt the passive downdraught cooling system to the climatic context of our region. The results show that a temperature difference of 15 °C and a humidity level of 50 % can be attained during overheating periods. These results confirm that this system can be an adequate solution in the different arid regions of southern Algeria.

Biodegradable Films Prepared from Pulp Lignocellulose Adhesives of Urea Formaldehyde Resin Modified by Biosulfonate.

Traditional low-density polyethylene (LDPE) film causes environmental pollution; there is a pressing need to make new bio-based polymers for alternative products, to meet agricultural production needs and for sustainable ecological development. In this study, urea-formaldehyde resin (UF) was modified with polyvinyl alcohol (PVA) and 1–2.5% bio-based sulfonate (BBS). The influence of BBS inducing on the functional groups, microstructure, and thermal behavior was evaluated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). A biodegradable film was prepared with modified UF resin as adhesive and pulp lignocellulose as raw material. The biodegradable mulch film samples were tested for biodegradability, water retention, and cooling soil temperature characters using LDPE and no mulching (NM) as a control. The results showed that with the increase of BBS content, the viscosity and reactivity of modified PUF resin increased, and the free formaldehyde content decreased. A 2%BBS modified PUF resin (2.0BBS/PUF) accelerated the curing process of the PUF resin, formed a flexible macromolecular network structure, and enhanced the toughness of the resin. The biodegradable mulch prepared with PUF, BBS, and 2.0BBS/PUF as adhesives had good water retention. BBS modification increased the degradation rate of mulch by 17.53% compared to the PUF. Three biodegradable films compared with LDPE and NM significantly reduced the soil temperature under summer cucumber cultivation, and the 2.0BBS/PUF coating had the lowest diurnal temperature difference, which provided a suitable soil environment for crop growth.

Proposed specific heat capacity model for a concrete wall containing phase change material (PCM) under field experiment conditions

This study compares (1) the specific heat capacity (CP) model obtained from the differential scanning calorimetry (DSC) measurement, (2) the conventional CP model using the step function and normal distribution function, and (3) the newly proposed CP model using the non-central F-distribution function. The CP models were implemented into the numerical conductive heat transfer model for the PCM-containing Portland cement (PC) concrete wall. Except for the heat capacity of PCM, other experimental data such as density, thermal conductivity, heat flux, or inner temperature profiles were obtained from the previous studies to build the numerical model. Through the validation process, the CP model using the non-central F-distribution function was selected as the best model, including the thermal properties of PCM. The proposed model was applied to the parametric study to investigate the best thermal efficiency, such as thermal comfort and diurnal temperature difference when applying PCM to PC concrete walls.