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Climate change is forcing action to reduce energy consumption and greenhouse gas emissions. An extremely important area of high-polluting energy consumption is material transport and, within this, the transport of chilled goods, including deep-frozen goods, is an important contributor. Phase change materials (PCMs) can have an important role in reducing energy consumption for the transport of chilled goods, but the current state of knowledge is not sufficient to bring the solution into popular use. This article includes a study of the effect of implementing microencapsulated PCM (mPCM) in polyurethane foam (PU) on the insulation performance of refrigerated trailer walls in low-temperature transport. In this research, mPCM was used, characterised by a phase-change heat in the range of 170–195 kJkg and a phase change temperature in the range from −10 °C to −9 °C. The studies performed show the potential of using mPCMs to improve the insulation performance of the walls of refrigerated trailers. Containing mPCM in the amount of 5.0% wt. placed throughout the entire volume of the wall can improve thermal conductivity of the wall for up to 15% in peak and 4.5% (0.2792 Wm2K without mPCM and 0.2665 Wm2K with mPCM) in the phase change temperature range. Out of the range of phase change temperatures, the thermal conductivity of the wall with mPCM is worse for 2.72% than in walls without PCM. Problems that need to be tackled were also identified, before the solution can be put into everyday use, i.e., finding the technology to increase the proportion of mPCMs relative to PU.

The invasive aquatic macrophyte Pontederia crassipes (water hyacinth) exhibits exceptional adaptability across a wide range of light environments, yet the mechanistic basis of its photosynthetic plasticity under both high- and low-light stress remains poorly resolved. This study integrated chlorophyll fluorescence and gas-exchange analyses to evaluate three photosynthetic models—rectangular hyperbola (RH), non-rectangular hyperbola (NRH), and the Ye mechanistic model—in capturing light-response dynamics in P. crassipes. The Ye model provided superior accuracy (R2 > 0.996) in simulating the net photosynthetic rate (Pn) and electron transport rate (J), outperforming empirical models that overestimated Pnmax by 36–46% and Jmax by 1.5–24.7% and failed to predict saturation light intensity. Mechanistic analysis revealed that P. crassipes maintains high photosynthetic efficiency in low light (LUEmax = 0.030 mol mol−1 at 200 µmol photons m−2 s−1) and robust photoprotection under strong light (NPQmax = 1.375, PSII efficiency decline), supported by a large photosynthetic pigment pool (9.46 × 1016 molecules m−2) and high eigen-absorption cross-section (1.91 × 10−21 m2). Unlike terrestrial plants, its floating leaves experience enhanced irradiance due to water-surface reflection and are decoupled from water limitation via submerged root uptake, enabling flexible stomatal and energy regulation. Distinct thresholds for carboxylation efficiency (CEmax = 0.085 mol m−2 s−1) and water-use efficiency (WUEi-max = 45.91 μmol mol−1 and WUEinst = 1.96 μmol mmol−1) highlighted its flexible energy management strategies. These results establish the Ye model as a reliable tool for characterizing aquatic photosynthesis and reveal how P. crassipes balances light harvesting and dissipation to thrive in fluctuating environments. These resulting insights have implications for both understanding invasiveness and managing eutrophic aquatic systems.

This study addressed whether competition under different light environments was reflected by changes in leaf absorbed light energy partitioning, photosynthetic efficiency, relative growth rate and biomass allocation in invasive and native competitors. Additionally, a potential allelopathic effect of mulching with invasive Prunus serotina leaves on native Quercus petraea growth and photosynthesis was tested. The effect of light environment on leaf absorbed light energy partitioning and photosynthetic characteristics was more pronounced than the effects of interspecific competition and allelopathy. The quantum yield of PSII of invasive P. serotina increased in the presence of a competitor, indicating a higher plasticity in energy partitioning for the invasive over the native Q. petraea, giving it a competitive advantage. The most striking difference between the two study species was the higher crown-level net CO2 assimilation rates (Acrown) of P. serotina compared with Q. petraea. At the juvenile life stage, higher relative growth rate and higher biomass allocation to foliage allowed P. serotina to absorb and use light energy for photosynthesis more efficiently than Q. petraea. Species-specific strategies of growth, biomass allocation, light energy partitioning and photosynthetic efficiency varied with the light environment and gave an advantage to the invader over its native competitor in competition for light. However, higher biomass allocation to roots in Q. petraea allows for greater belowground competition for water and nutrients as compared to P. serotina. This niche differentiation may compensate for the lower aboveground competitiveness of the native species and explain its ability to co-occur with the invasive competitor in natural forest settings.

A new mechanistic model of the photosynthesis–light response is developed based on photosynthetic electron transport via photosystem II (PSII) to specifically describe light-harvesting characteristics and associated biophysical parameters of photosynthetic pigment molecules. This model parameterizes ‘core’ characteristics not only of the light response but also of difficult to measure physical parameters of photosynthetic pigment molecules in plants. Application of the model to two C3 and two C4 species grown under the same conditions demonstrated that the model reproduced extremely well (r 2 > 0.992) the light response trends of both electron transport and CO2 uptake. In all cases, the effective absorption cross-section of photosynthetic pigment molecules decreased with increasing light intensity, demonstrating novel operation of a key mechanism for plants to avoid high light damage. In parameterizing these previously difficult to measure characteristics of light harvesting in higher plants, the model provides a new means to understand the mechanistic processes underpinning variability of CO2 uptake, for example, photosynthetic down-regulation or reversible photoinhibition induced by high light and photoprotection. However, an important next step is validating this parameterization, possibly through application to less structurally complex organisms such as single-celled algae.

The study evaluates the accuracy of two FvCB model sub-models (I and II) in estimating the maximum electron transport rate for CO2 assimilation (JA-max) by comparing estimated values with observed maximum electron transport rates (Jf-max) in four C3 species: Triticum aestivum L., Silphium perfoliatum L., Lolium perenne L., and Trifolium pratense L. Significant discrepancies were found between JA-max estimates from sub-model I and observed Jf-max values for T. aestivum, S. perfoliatum, and T. pratense (p < 0.05), with sub-model I overestimating JA-max for T. aestivum. Sub-model II consistently produced higher JA-max estimates than sub-model I. This study highlights limitations in the FvCB sub-models, particularly their tendency to overestimate JA-max when accounting for electron consumption by photorespiration (JO), nitrate reduction (JNit), and the Mehler reaction (JMAP). An alternative empirical model provided more accurate Jf-max estimates, suggesting the need for improved approaches to model photosynthetic electron transport. These findings have important implications for crop yield prediction, ecological modeling, and climate change adaptation strategies, emphasizing the need for more accurate estimation methods in plant physiology research.

Forest tree seedling production technologies impact reforestation success determined with survival and quality of seedlings. Five Abies alba seedling production technologies were tested: (1) bare-root seedling, three years in the open (3/0); (2) bare-root seedling, two years under a shading net (40% of full light), a year in the open (2/g); (3) ball root seedling, two years under a shading net (40%), a year in the open (2/K); (4) bare-root seedling grown in an opening in a Norway spruce stand (3/Pic); (5) bare-root seedling, three years under Scots pine canopy (3/Pin). Silver fir seedlings acclimatized their growth rates to the common growing environment in relation to the seedling production technology used in the nurseries. The height and diameter at root collar were positively correlated with survival. The 3/Pic seedlings manifested the lowest survival and were lower than other seedlings in terms of height and photochemical efficiency. The needle photochemistry of seedlings growing two years in plantation was determined by their earlier acclimation to the nursery light conditions. The production technology determined the ability of A. alba seedlings to acclimatize to the natural environment. Ball root seedlings grown two years in shade and a year in the open (2/K) acclimatized better to the full light environment compared with bare-root seedlings produced in canopy shade, and they are likely more suitable to be planted after clearcutting.

Effective quantum efficiency of photosystem II (Φ PSII ) represents the proportion of photons of incident light that are actually used for photochemical processes, which is a key determinant of crop photosynthetic efficiency and productivity. A robust model that can accurately reproduce the nonlinear light response of Φ PSII (Φ PSII – I ) over the I range from zero to high irradiance levels is lacking. In this study, we tested a Φ PSII – I model based on the fundamental properties of light absorption and transfer of energy to the reaction centers via photosynthetic pigment molecules. Using a modeling-observation intercomparison approach, the performance of our model versus three widely used empirical Φ PSII – I models were compared against observations for two C 3 crops (peanut and cotton) and two cultivars of a C 4 crop (sweet sorghum). The results highlighted the significance of our model in (1) its accurate and simultaneous reproduction of light response of both Φ PSII and the photosynthetic electron transport rate ( ETR ) over a wide I range from light limited to photoinhibition I levels and (2) accurately returning key parameters defining the light response curves.

Background: Poland was one of only 10 European countries listed teachers as a priority group for vaccination against COVID-19 among National Vaccination Program (NVP). The aim of this study was to analyse post-vaccination symptoms self-reported by teachers vaccinated under the national COVID-19 vaccination programme. Methods: The presented cross-sectional survey was conducted among teachers from all levels of education in public and non-public institutions, who received the SARS-CoV-2 virus vaccination campaign with the vaccine from AstraZeneca as part of the NVP. The survey was conducted using an original, self-designed questionnaire prepared for this study and distributed to teachers in the form of an online survey via email. Bayesian logistic and linear regression were used to estimate the relationship between predictors and dependent variables. Results: A total of 4622 teachers took part in the survey. Of this number, 3908 teachers declared that they had taken the vaccine. (84.5%). In the study group, self-reported late post-vaccination reactions were very strongly [logBF > 3.4] associated with both gender and age. In contrast, self-reporting of serious late post-vaccination symptoms other than fever was very strongly associated only with gender. Only a small proportion of teachers (from 1.45% to 5.34% depending on age and gender) self-reported immediate post-vaccination reaction (up to 15 min after injection). Conclusions: Self-reporting of symptoms is a valuable tool for monitoring the effectiveness and safety of vaccinations and can also contribute to increased satisfaction with the vaccination process, especially when patients are made aware that post-vaccination symptoms are a natural sign of the body’s immune response.

Investigation on intrinsic properties of photosynthetic pigment molecules participating in solar energy absorption and excitation, especially their eigen-absorption cross-section ( σ ik ) and effective absorption cross-section ( σ ′ ik ), is important to understand photosynthesis. Here, we present the development and application of a new method to determine these parameters, based on a mechanistic model of the photosynthetic electron flow-light response. The analysis with our method of a series of previously collected chlorophyll a fluorescence data shows that the absorption cross-section of photosynthetic pigment molecules has different values of approximately 10 −21 m 2 , for several photosynthetic organisms grown under various conditions: (1) the conifer Abies alba Mill., grown under high light or low light; (2) Taxus baccata L., grown under fertilization or non-fertilization conditions; (3) Glycine max L. (Merr.), grown under a CO 2 concentration of 400 or 600 μmol CO 2 mol −1 in a leaf chamber under shaded conditions; (4) Zea mays L., at temperatures of 30°C or 35°C in a leaf chamber; (5) Osmanthus fragrans Loureiro, with shaded-leaf or sun-leaf; and (6) the cyanobacterium Microcystis aeruginosa FACHB905, grown under two different nitrogen supplies. Our results show that σ ik has the same order of magnitude (approximately 10 −21 m 2 ), and σ ′ ik for these species decreases with increasing light intensity, demonstrating the operation of a key regulatory mechanism to reduce solar absorption and avoid high light damage. Moreover, compared with other approaches, both σ ik and σ ′ ik can be more easily estimated by our method, even under various growth conditions (e.g., different light environment; different CO 2 , NO 2 , O 2 , and O 3 concentrations; air temperatures; or water stress), regardless of the type of the sample (e.g., dilute or concentrated cell suspensions or leaves). Our results also show that CO 2 concentration and temperature have little effect on σ ik values for G. max and Z. mays . Consequently, our approach provides a powerful tool to investigate light energy absorption of photosynthetic pigment molecules and gives us new information on how plants and cyanobacteria modify their light-harvesting properties under different stress conditions.

The models used to describe the light response of electron transport rate in photosynthesis play a crucial role in determining two key parameters i.e., the maximum electron transport rate ( J max ) and the saturation light intensity ( I sat ). However, not all models accurately fit J – I curves, and determine the values of J max and I sat . Here, three models, namely the double exponential (DE) model, the non-rectangular hyperbolic (NRH) model, and a mechanistic model developed by one of the coauthors (Z-P Ye) and his coworkers (referred to as the mechanistic model), were compared in terms of their ability to fit J–I curves and estimate J max and I sat . Here, we apply these three models to a series of previously collected Chl a fluorescence data from seven photosynthetic organisms, grown under different conditions. Our results show that the mechanistic model performed well in describing the J–I curves, regardless of whether photoinhibition/dynamic down-regulation of photosystem II (PSII) occurs. Moreover, both J max and I sat estimated by this model are in very good agreement with the measured data. On the contrary, although the DE model simulates quite well the J–I curve for the species studied, it significantly overestimates both the J max of Amaranthus hypochondriacus and the I sat of Microcystis aeruginosa grown under NH 4 + -N supply. More importantly, the light intensity required to achieve the potential maximum of J ( J s ) estimated by this model exceeds the unexpected high value of 10 5 μmol photons m −2 s −1 for Triticum aestivum and A. hypochondriacus . The NRH model fails to characterize the J-I curves with dynamic down-regulation/photoinhibition for Abies alba , Oryza sativa and M. aeruginosa . In addition, this model also significantly overestimates the values of J max for T. aestivum at 21% O 2 and A. hypochondriacus grown under normal condition, and significantly underestimates the values of J max for M. aeruginosa grown under NO 3 – N supply. Our study provides evidence that the ‘mechanistic model’ is much more suitable than both the DE and NRH models in fitting the J–I curves and in estimating the photosynthetic parameters. This is a powerful tool for studying light harvesting properties and the dynamic down-regulation of PSII/photoinhibition.