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Climate change, characterized by rising atmospheric CO 2 levels and temperatures, poses significant challenges to global crop production. Sweet sorghum, a prominent C 4 cereal extensively grown in arid areas, emerges as a promising candidate for sustainable bioenergy production. This study investigated the responses of photosynthesis and leaf-scale water use efficiency (WUE) to varying light intensity ( I ) in sweet sorghum under different temperature and CO 2 conditions. Comparative analyses were conducted between the A n - I , g s - I , T r - I , WUE i - I , and WUE inst - I models proposed by Ye et al. and the widely utilized the non-rectangular hyperbolic (NRH) model for fitting light response curves. The Ye's models effectively replicated the light response curves of sweet sorghum, accurately capturing the diminishing intrinsic WUE (WUE i ) and instantaneous WUE (WUE inst ) trends with increasing I . The fitted maximum values of A n , g s , T r , WUE i , and WUE inst and their saturation light intensities closely matched observations, unlike the NRH model. Despite the NRH model demonstrating high R 2 values for A n - I , g s - I , and T r - I modelling, it returned the maximum values significantly deviating from observed values and failed to generate saturation light intensities. It also inadequately represented WUE responses to I , overestimating WUE. Across different leaf temperatures, A n , g s , and T r of sweet sorghum displayed comparable light response patterns. Elevated temperatures increased maximum A n , g s , and T r but consistently declined maximum WUE i and WUE inst . However, WUE inst declined more sharply due to the disproportionate transpiration increase over carbon assimilation. Critically, sweet sorghum A n saturated at current atmospheric CO 2 levels, with no significant gains under 550 μmol mol -1 . Instead, stomatal closure enhanced WUE under elevated CO 2 by coordinated g s and T r reductions rather than improved carbon assimilation. Nonetheless, this response diminished under simultaneously high temperature, suggesting intricate interplay between CO 2 and temperature in modulating plant responses. These findings provide valuable insights into photosynthetic dynamics of sweet sorghum, aiding predictions of yield and optimization of cultivation practices. Moreover, our methodology serves as a valuable reference for evaluating leaf photosynthesis and WUE dynamics in diverse plant species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Yang, Ma, Ye, Yang, Shi, Wang, Zhou, Wang and Deng.)

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., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ye, Stirbet, An, Robakowski, Kang, Yang and Wang.)

Light response curve of photosynthesis ( A n - I curve) is a useful modeling tool to investigate how photosynthesis reacts with different abiotic factors, which would help quantify the response of photosynthetic rate to photosynthetically active radiation. Based on the mathematical characteristics of photosynthesis A n - I models, we reviewed the advantages of using these model in practice and the potential caveats. We proposed the development of new mechanistic photosynthesis A n - I models based on the primary light response and discussed its advantages in the field of plant ecology and physiology. Photosynthesis has three main steps, including the primary reaction, the assimilatory power forms, and the carbon assimilation. Changes in each step could directly affect the photochemical efficiency and carbon assimilation in photosynthesis. The primary reaction consists of a series of physical processes that are related to light energy absorption and utilization, including the absorption of light energy, the change of quantum state, and the transfer and de-excitation of exciton resonance of light-trapping pigment molecules. How-ever, the empirical photosynthesis A n - I models can not explain some scenarios. For example, the non-photochemical quenching in plants increases with increasing light intensity in a non-linear manner. Further, the life-time of singlet chlorophyll molecules can be extended when plant light-harvesting pigment molecules absorb excessive light energy but would not be immediately used for the photochemical reaction. Meanwhile, the parameters obtained by fitting the mechanistic A n - I curve model can not only reflect the primary photochemical reaction characteristics of plants, but also describe the physical characteristics of plant light harvesting pigment molecules, such as the number of light harvesting pigment molecules in the excited state ( N k ) and effective light energy absorption cross-section ( σ ik '). This can be used to further investigate the physical characteristics of light harvesting pigment molecules, including the light-response of N k and σ ik ' and the average life time of light harvesting pigment molecules in the lowest exciting state ( τ min ). In addition, it would be necessary to determine how to incorporate abiotic factors, such as temperature and CO 2 concentration, into the mechanistic A n - I curve model, as well as to determine the association between the abiotic factors and light harvesting pigment molecules, such as N k , σ ik ', and τ min .

Objective: To develop a machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding and to evaluate its effectiveness of field application, so as to provide a novel Oncomelania hupensis snail control technique in the large-scale marshlands., Methods: The machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding, which was suitable for use in complex marshland areas, was developed according to the mechanization and automation principles, and was used for O. hupensis snail control in the marshland. The effect of the machine on environmental cleaning and plough was evaluated, and the distribution of living snails was observed at various soil layers following plough. The snail control effects of plough alone and plough followed by mollusciciding were compared., Results: The machine could simultaneously complete the procedures of getting vegetation down and cut vegetation into pieces, plough and snail control by spraying niclosamide. After plough, the constituent ratios of living snails were 36.31%, 25.60%, 22.62% and 15.48% in the soil layers at depths of 0-5, 6-10, 11-15 cm and 16-20 cm respectively, and 61.91% living snails were found in the 0-10 cm soil layers. Seven and fifteen days after the experiment, the mortality rates of snails were 9.38% and 8.29% in the plough alone group, and 63.04% and 80.70% in the plough + mollusciciding group respectively (χ²₇ d = 42.74, χ²₁₅ d = 155.56, both P values < 0.01). Thirty days after the experiment, the densities of snails were 3.02 snails/0.1 m² and 0.53 snails/ 0.1 m² in the soil surface of the plough alone group and the plough + mollusciciding group, which decreased by 64.92% and 93.60%, respectively, and the decrease rate of snail density was approximately 30% higher in the plough + mollusciciding group than that in the plough alone group., Conclusions: The machine simultaneously integrating mechanized environmental cleaning and automatic mollusciciding achieves the integration of mechanical environmental cleaning and automatic niclosamide spraying in the complex marshland areas, which provides a novel technique of field snail control in the large-scale setting in China.

Objective: To evaluate the field molluscicidal effect of 5% niclosamide ethanolamine granules, so as to provide a novel Oncomelania hupensis snail control approach for emergency treatment of high-risk settings., Methods: Snail control tests with spraying of 5% niclosamide ethanolamine granules were conducted in two settings of 2 counties, and the dose-, time- and setting-specific field molluscicidal effects were tested., Results: In the small-scale setting, spraying of 5% niclosamide ethanolamine granules at doses of 30, 40 and 50 g/m2 resulted in 54.55%, 68.41% and 73.45% 1-day snail mortality, 57.27%, 68.59% and 80.28% 3-day snail mortality, and 63.49%, 77.58% and 85.55% 7-day snail mortality, respectively, and no significant differences were detected in 1- and 3-day snail mortality caused by spraying of 5% niclosamide ethanolamine granules at doses of 30 and 40 g/m2 (all P > 0.05), while significant difference was found in the 7-day snail mortality (χ2 = 4.549, P < 0.05). In addition, spraying of 5% niclosamide ethanolamine granules at doses of 40 and 50 g/m2 resulted in comparable 1-, 3- and 7-day snail mortality (all P > 0.05). In the large-scale setting, spraying of 5% niclosamide ethanolamine granules at a dose of 40 g/m2 resulted in 85.29% and 87.70% 3-day snail mortality, 83.89% and 91.02% 7-day snail mortality, and 83.41% and 91.84% 15-day snail mortality in the environment-cleaning group and non-cleaning group, respectively. The overall snail mortality was 90.02% in the environment-cleaning group 3 to 15 days after spraying, which was significantly higher than that (84.28%) in the non-cleaning group (χ2 = 9.950, P < 0.05). After 15 days of spraying with 5% niclosamide ethanolamine granules at a dose of 40 g/m2, the densities of living snails reduced from 19.90 and 19.83 snails/0.1 m2 to 0.60 and 2.60 snails/0.1 m2 in the environment-cleaning group and non-cleaning group, with 96.98% and 86.89% reductions, respectively., Conclusion: The appropriate dose of 5% niclosamide ethanolamine granules is 40 g/m2 for snail control in the field, and environment cleaning of vegetation with a height of more than 50 cm may improve the molluscicidal efficacy.

To aim at the characteristics of epidemic situation that the imported falciparum malaria cases increased year by year in Yangzhou City, an imported falciparum malaria control system was established. This control system was based on enhancing the management of returned labor service export persons from falciparum malaria endemic areas, the active medical remind service, the diagnostic capability and health education, and the cooperation of medical personnel and patients, and also avoiding diagnosis delay and misdiagnosis and promoting the treatment in time so as to decrease the serious patients and prevent them from death. After the application of the control system, there were 164 imported falciparum malaria cases from the returned persons of labor service export. The time from the attack of the disease to the diagnosis confirmed decreased from 6.8 days before the application of the system to 2.7 days after the application, and the rate of serious patients was 1.8% and there were no death cases.

Objective: To analyze the current situation of the comprehensive prevention and control system for imported falciparum malaria in Hanjiang District and evaluate its effect., Methods: According to the Management Scheme on Control of Imported Falciparum Malaria in Yangzhou City, the comprehensive prevention and control system for imported falciparum malaria was implemented, and the relevant malaria data were collected and analyzed statistically. The data included plasmodium blood test ratio of fever patients among exported labors and those returned, the ratio of laboratory-confirmed cases among all reported cases of falciparum malaria, the ratio of falciparum malaria patients who received the standard treatment within 24 hours after onset, etc from 2010 to 2012., Results: After the implementation of the comprehensive prevention and control system, the confirmation ratio of falciparum malaria cases within 24 hours following first visit has reached 60.47%, the average time from first visit to confirmation has shortened to 1.8 d, and the average time from onset to confirmation has shortened to 3.7 d. The health education coverage ratio was 100%, the health knowledge awareness ratio was 95.56%, the ratio of patients seeking treatment on own initiative was 100%, the laboratory-confirmed ratio was 100%, and the ratio of standard treatment after malaria diagnosis was 100%., Conclusion: The comprehensive prevention and control system carried out by Hanjiang District has made remarkable achievements.

The endemic situation of schistosomiasis and Oncomelania snail status in Yanjiang Village, Hanjiang District decreased significantly from 2005 to 2010. However, the surveillance in key population such as fishmen and boatmen still needs to be strengthened.