Net Rate Research Articles

Lanthanum and cerium added to soil influence microbial carbon and nitrogen cycling genes

The soil microbiome plays an important role in carbon (C) and nitrogen (N) processing and storage and is influenced by rare earth elements (REEs), which can have both direct and indirect effects on plant metabolic processes. Using conventional physicochemical methods and metagenomic-based analyses, we investigated REEs effects on soil respiration, soil mineral N, soil microbial community structure and functional genes related to C and N metabolism. High doses of cerium (0.16 and 0.32 mmol kg−1 soil) increased CO2 net production rate by 59 and 42%, and N2O net production rate by 255 and 609%, respectively, compared to no REEs. Similarly, high doses of lanthanum (0.16 and 0.32 mmol kg−1 soil) increased CO2 net production rate by 47 and 39%, and N2O net production rate by 105 and 187%, respectively. Increased soil respiration from altered relative abundances of key soil microorganisms associated with soil N cycling and organic matter degradation and functional genes encoding enzymes involved in C and N metabolism, accelerated N mineralization. Elevated REEs levels substantially increased the relative abundances of functional genes related to cellulose, chitin, glucans, hemicellulose, lignin, and peptidoglycan degradation. REEs also influenced multiple functional genes associated with the N cycle. The abundance of genes responsible for organic N degradation and synthesis, such as asnB, gdh_K15371, glsA, and gs, increased with elevated cerium and lanthanum concentrations. Similarly, the abundances of denitrification genes, including narl, narJ, narZ, and nosZ, also rose with increasing amounts of cerium and lanthanum. However, the decrease in narB and nirB gene abundance with increasing REE concentrations was attributed to the reduction of nitrate to amino groups. Our findings highlight the influence of REEs on key soil microorganisms associated with soil N cycling and organic matter degradation and key functional genes in soil C and N metabolism, with implications for agriculture, environmental protection, and human health.

Analisis Angka Mortalitas pada Tahun 2023 Sampai Triwulan Pertama Tahun 2024 Berdasarkan Indikator Gross Death Rate (GDR) dan Net Death Rate (NDR) di Rumah Sakit X

The purpose of this research is to determine the mortality rates for both the gross and net deaths, data sources, and statistical activities from 2023 to the first quarter of 2024 at X Hospital. Combining evaluation studies—that is, qualitative and quantitative—with a descriptive research methodology. The data processing techniques are interviewing and observation. The qualitative data is processed using an inductive approach, and the quantitative data is processed using bivariate analysis. The population is the research informant, consisting of 5 officers, and the object is the Monthly Recapitulation Form of Hospitalized Patients. The study's results show that the Republic of Indonesia's (Depkes RI) Ministry of Health has set standards for Gross Death Rate <45% and Net Death Rate <25%. The study's results show that the Gross Death Rate value in 2023 is 21.02%, while the Net Death Rate value is 7.15%. The study concludes that the data source obtained is the result of a monthly recapitulation of hospitalized patients with statistical activities in reporting data processing according to the formula used for calculating the Gross Death Rate and Net Death Rate values and the data is presented in Microsoft Excel as tables and graphs.

Bottom-Up Effects of Various Plant Growth Promoting Treatments on Fitness Parameters of Hippodamia variegata.

Plant growth-promoting activities using biological, chemical, and organic fertilizers are well-documented for pest insects, their impacts on predators are less commonly studied. This research investigates whether bell pepper plants treated with plant growth-promoting rhizobacteria (PGPRs), arbuscular mycorrhizal fungi (AMF), vermicompost (30%), and zinc sulfate either separately or in selected combinations affect the nutrient indices and population growth traits of the ladybug predator, Hippodamia variegata (Goeze), when fed on aphids, Myzus persicae (Sulzer). Bell pepper plants were individually treated with two PGPRs (Bacillus subtilis and Pseudomonas fluorescens), one AMF (Glomus intraradices), soil amended with 30% vermicompost (v/v), and foliar application of zinc sulfate under greenhouse conditions. Combined treatments of AMF × B. subtilis and AMF × P. fluorescens were also tested. Nutritional indices and population growth parameters of predator were reared on the treated plants infested with aphids. Results showed that the efficiency of conversion of ingested food (ECI) in predator larvae was highest on B. subtilis-treated aphids and lowest on vermicompost-treated aphids. The relative growth rate (RGR) of predator was the highest on zinc sulfate-treated aphids and lowest on vermicompost-treated aphids. Predators fed on vermicompost-treated aphids had the lowest net reproductive rate (R₀) and intrinsic rate of increase (r), while R₀ was highest for predators fed on B. subtilis-treated aphids and r was highest on P. fluorescens- and B. subtilis-treated aphids. These findings suggest that zinc sulfate and biological fertilizers involving PGPRs can enhance the ecological fitness of predators and could be effective in biocontrol-based integrated pest management of aphids.

Density-dependent fitness and mass-rearing of Habrobracon hebetor (Say) (Hymenoptera: Braconidae) incorporating life table variability

The ectoparasitoid Habrobracon hebetor (Say) (Hymenoptera: Braconidae) is an important natural enemy insect deployed for controlling lepidopteran larvae in warehouses and fields. However, there is limited information on mass-rearing methods of H. hebetor. This study investigated the effects of different Ephestia elutella (Hübner) (Lepidoptera: Pyralidae) and parasitic egg densities on the fitness and mass-rearing efficiency of H. hebetor, aiming to determine the optimal conditions for developing an economically viable and sustainable mass-rearing system for this parasitoid. Our results showed that the average number of eggs laid per host dropped below 7.54 eggs when the number of hosts exceeded five. H. hebetor exhibited significantly increased preadult survival rate (67.41%-81.00%), female and male body size (2224.55-2379.83 μm, 2213.39-2324.65 μm), fecundity (443.98-492.43 eggs), net reproductive rate (R0=154.57-216.67 offspring), intrinsic rate of increase (r=0.2776-0.3223 d-1), net paralyzed rate (C0=72.37-93.17 larvae), and net parasitism rate (Z0=43.55-55.04 larvae) at a density of 5-15 eggs per host than at 20 eggs per host. Meanwhile, considering rearing costs and production rate, a density of 5-15 eggs per host proved to be the most economical for mass-rearing H. hebetor, achieving a daily harvest rate of 10,000 newly emerged female adults. Therefore, for an efficient mass-rearing system for H. hebetor, maintaining a density of 5-15 eggs per host is recommended considering variability in life table and discarding aged individuals (after 36 days old). In summary, providing 5-10 5th instar larvae of E. elutella per day per pair of male and female parasitoid wasps is advised for effective mass-rearing of H. hebetor.

Varying effects of climate change on the photosynthesis and calcification of crustose coralline algae: Implications for settlement of coral larvae

Coral recruitment is critical to the maintenance of healthy coral reef ecosystems. Many coral species settle preferentially on certain crustose coralline algae (CCA) (e.g., Hydrolithon boergesenii) over others (e.g., Paragoniolithon solubile). Calcifying organisms like CCA are particularly susceptible to ocean acidification (OA), and settlement behavior of larvae may be compromised as seawater temperatures increase (ocean warming; OW) and pH levels decrease as a result of climate change. Here, we examine the effects of future seawater conditions (OW and OA) on the calcification and photosynthetic efficiency of two CCA species, H. boergesenii and Pa. solubile. We also examine the effects of conditioning CCA in combined OA and OW on the settlement preferences of three coral species, Acropora palmata, A. cervicornis and Porites astreoides. Acropora palmata and Po. astreoides demonstrated a preference for H. boergesenii over Pa. solubile in choice experiments after short-term treatment (7–21 days) and this preference was not affected by future seawater conditions. A. cervicornis did not demonstrate a CCA preference under any treatment. Po. astreoides did not demonstrate a CCA preference in no-choice assays and settlement was unaffected by OW and OA even after the longest exposure (99 days). Both CCA had reduced photosynthetic efficiency after exposure to future seawater conditions. However, net calcification rate was reduced in H. boergesenii but not Pa. solubile after exposure to future seawater conditions. These results demonstrate that while climate change may differentially affect the physiological functioning of various species of CCA, coral settlement preferences are unlikely to be altered.

Advanced growing-season precipitation peak promotes soil nitrogen mineralization in a semi-arid grassland

Soil nitrogen (N) mineralization is a key process of global N cycling and profoundly regulates plant productivity and soil nutrient pools in the terrestrial biosphere. However, its response to seasonal precipitation redistribution remains largely unexplored. As part of a nine-year (2013–2021) field experiment that simulated advanced and/or delayed growing-season precipitation peaks in a semi-arid grassland on the Mongolian Plateau, this study was conducted for two years (2020–2021) in situ to examine the effects of changing precipitation distributions in the growing seasons on soil mineralization processes. The results showed that advanced precipitation peak (AP) increased soil ammonification (Ramm), nitrification (Rnit), and net mineralization rates (Rmin) by 45.8 %, 26.0 %, and 84.4 %, respectively (all p < 0.001), whereas delayed precipitation peak (DP) enhanced Ramm by 55.7 % (p < 0.001) only, but did not change Rnit or Rmin. The elevated soil N mineralization under the AP treatment could be primarily attributed to the increased soil water availability and microbial biomass N in the early growing season, both of which play essential roles in meditating biological processes in the soil. In addition, the large consumption of soil inorganic N in the early and middle growing seasons may lead to an enhancement of ammonification in September. These observations suggest that advanced rather than delayed growing-season precipitation peak has a stronger influence on soil N dynamics in the growing seasons. Moreover, our findings highlight the positive contributions of altered N transformations to soil respiration and net ecosystem productivity under the AP treatment and imply the crucial roles of intra-annual redistribution of precipitation in regulating ecosystem nutrient and carbon cycling in semi-arid regions.

Evaluation of Physiological Parameters and Growth Phenology in Rice Cultivars under Irrigated Conditions of Raipur Plain

An experiment was conducted to examine the physiological and growth parameters of various rice (Oryza sativa.L.) varieties under irrigated conditions in the Raipur plain during kharif season 2023-24. The research focused on key metrics including crop growth rate (CGR), absolute growth rate (AGR), net assimilate rate (NAR), and relative growth rate (RGR) to evaluate the performance of different rice varieties in this region. Results showed significant variation among the rice varieties in their growth and physiological responses. Varieties with higher CGR and AGR demonstrated superior biomass accumulation and overall growth performance. Those with elevated NAR and RGR exhibited more efficient conversion of assimilates into plant biomass, reflecting better productivity. The findings underscore the importance of selecting rice varieties based on their growth metrics and physiological efficiency under specific irrigated conditions.

Impact of modified atmospheres enriched with carbon dioxide on the survival, biological, and physiological aspects of Aleuroglyphus ovatus (Troupeau, 1878)

Aleuroglyphus ovatus (Troupeau, 1878), a prevalent mite within stored products, inflicts substantial economic and health risks. The use of fumigants and grain protectants as methods of stored grain pest management had resulted in resistance and environmental concerns, necessitating alternative strategies. This study explored the toxicity of modified atmospheres composed of CO2, as an environmentally friendly, residue-free, and viable disinfestation alternative. The mortality of A. ovatus increased significantly with an increase in either CO2 concentration or exposure duration. Complete adult mortality was recorded after 72 h of treatment with 95% CO2. The calculated LT50 value was 30.52 h under 35% CO2, and it decreased to 11.78 h under 95% CO2. Additionally, CO2 exposure led to changes in the activity of antioxidant and detoxification enzymes in A. ovatus, indicating its physiological adaptation mechanisms under varying CO2 concentrations and the impact of these changes on development and reproductive capacity. Enzymatic assays revealed a concentration-dependent decrease in superoxide dismutase activity and an increase in catalase activity. The detoxification enzymes, glutathione S-transferase, and carboxylesterase demonstrated adaptive upregulation. The development of A. ovatus was delayed, and its reproductive capacity was reduced under CO2 stress. Population parameters, including the net reproductive rate (R0) and intrinsic rate of increase (rm) were all significantly reduced under CO2 stress, with 35% CO2 showing the severer impact. The study concludes that CO2 can be an effective tool for pest management in stored products, with 35% CO2 showing potential as a more economical option for A. ovatus extermination.

The dual timescales of gait adaptation: initial stability adjustments followed by subsequent energetic cost adjustments.

Gait adaptation during bipedal walking allows people to adjust their walking patterns to maintain balance, avoid obstacles and avoid injury. Adaptation involves complex processes that function to maintain stability and reduce energy expenditure. However, the processes that influence walking patterns during different points in the adaptation period remain to be investigated. We assessed split-belt adaptation in 17 young adults aged 19-35. We also assessed individual aerobic capacity to understand how aerobic capacity influences adaptation. We analyzed step lengths, step length asymmetry (SLA), mediolateral margins of stability, positive, negative and net mechanical work rates, as well as metabolic rate during adaptation. Dual-rate exponential mixed-effects regressions estimated the adaptation of each measure over two timescales; results indicate that mediolateral stability adapts over a single timescale in under 1 min, whereas mechanical work rates, metabolic rate, step lengths and SLA adapt over two distinct timescales (3.5-11.2 min). We then regressed mediolateral margins of stability, net mechanical work rate and metabolic rate on SLA during early and late adaptation phases to determine whether stability drives early adaptation and energetic cost drives late adaptation. Stability predicted SLA during the initial rapid onset of adaptation, and mechanical work rate predicted SLA during the latter part of adaptation. Findings suggest that stability optimization may contribute to early gait changes and that mechanical work contributes to later changes during adaptation. A final sub-analysis showed that aerobic capacity levels <36 and >43 ml kg-1min-1 resulted in greater SLA adaptation, underscoring the metabolic influences on gait adaptation. This study illuminates the complex interplay between biomechanical and metabolic factors in gait adaptation, shedding light on fundamental mechanisms underlying human locomotion.

Erosion enhancement by impurity entrainment in the highly collisional plasmas of Magnum-PSI

Abstract Extrinsic impurity seeding is planned for ITER to avoid high heat fluxes to the tungsten divertor targets. Nevertheless, excessive sputtering by impurities would lead to a reduction in fusion power output and divertor lifetime. Unlike today's fusion devices, the entrainment of impurities is expected to play an increasing role in ITER's highly collisional near-surface plasma. Impurity entrainment refers to the acceleration of impurities with the plasma flow by collisional drag, leading to elevated impact energies. To investigate impurity entrainment under ITER-like plasma conditions ($n_e &gt; 2 \cdot 10^{20}$ m$^{-3}$, $T_e &lt;$ 5 eV), argon-seeded hydrogen plasmas were formed with the linear plasma generator Magnum-PSI. Doppler shifts in spatially-resolved emission profiles of argon (Ar II - 480.6 nm) and hydrogen (H$_\mathrm{\beta}$ - 486.1 nm) reveal the entrainment of seeded argon towards the upstream hydrogen velocity ($\sim$9 cm from surface), corresponding to $\sim$0.39 of the common-system sound speed. In addition, the sputtering yield of tungsten by argon bombardment for the argon-seeded hydrogen plasma was compared to a pure argon plasma by monitoring tungsten (W I - 400.9 nm) emission. These sputtering experiments indicate further entrainment of the argon impurities to $\sim$0.65 of the common-system sound speed at the sheath edge, leading to a large increase in their impact energy. Extrapolation of the Magnum-PSI results to ITER, using existing SOLPS-ITER simulations to determine the divertor plasma conditions, indicates more than an order of magnitude increase in gross erosion of the divertor targets due to impurity entrainment. However, the net erosion rate could still be kept under control if high re-deposition rates are achieved, which is treated in the companion paper \cite{Cornelissen2023}. The combination of a low sputtering threshold energy and high impact energy of impurities constrains the fine balance between radiative cooling with impurity seeding and avoiding extensive divertor erosion.

Attention should be paid to the application of net ultrafiltration rate in continuous renal replacement therapy for critically ill patients

Continuous renal replacement therapy (CRRT) plays a crucial role in the volume management for critically ill patients. Net ultrafiltration (NUF) rate, as an important therapeutic parameter of CRRT, has received widespread attention for its individualized prescription and functionin volume management of critically ill patients. The aim of this article is to identify the relationship between NUF rate settings and the prognosis of critically ill patients in the clinical practice of CRRT, determine the optimal therapeutic range of NUF rate, and thus improve the effect of CRRT volume management, and provide insights into to future NUF rate studies.

Financial Performance Assessment of Flat Buildings Using Life Cycle Cost and Cost–Benefit Analysis

Buildings resulting from construction projects are durable assets and decisions related to construction projects have enduring impacts. In many cases, building owners prioritize only the initial costs, such as building design, construction, and equipment costs, while neglecting the future operation and maintenance costs. This research studies life cycle costing (LCC) analysis to evaluate the financial feasibility of urban housing. The LCC calculates all the costs incurred and benefits during the building's operation. The cost is generated from construction, operational, and maintenance costs. At the same time, the benefit breaks down into flat rental costs, retail rental costs, and parking costs. The costs incurred are estimated over 25 years, and the parameters of feasibility are net Present Value (NPV), Benefit-Cost Ratio (BCR), and Internal Rate of Return (IRR). The study generates negative NPV, BCR &lt; 1, and 0.61% of IRR. It indicates that the project is not feasible. This research gives alternatives to make the project feasible. This study employed a trial-and-error approach to ascertain the viability of investing in flat rentals by systematically adjusting rental rates. Incremental adjustments to rental rates are tested by a series of rate hikes of 50%, 100%, 150%, and 200% using a trial-and-error approach. The project will become feasible if the flat rate increases to 150-200% of the initial rental rate.

Integrative Analysis of Metabolome and Transcriptome Profiles to Evaluate the Response Mechanisms of Carex adrienii to Shade Conditions

Carex is a type of herbaceous plant with high application value, playing an important role in the urban periphery. Due to its unique morphology and ecological characteristics, Carex is widely used in various fields, such as landscaping, ecological restoration and soil and water conservation, which help to maintain the balance of the ecosystem. In order to explore the potential molecular mechanisms of shade tolerance in Carex, transcriptome and metabolome sequencing were performed on the leaves of the shade = tolerant species Carex adrienii E. G. Camus. under 80% shade and no shade conditions. Compared to control group (CK), the total chlorophyll, chlorophyll a, chlorophyll b and total carotenoid content in the C. adrienii leaves of the shading treatment were significantly upregulated. The antioxidant enzyme activity of the leaves, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), were also remarkably upregulated in the shading treatment groups. In addition, the net photosynthesis rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of the leaves were reduced, and the intercellular CO2 concentration (Ci) of the leaves was increased under shade. The transcriptome identified 5056 differentially expressed genes (DEGs) and the metabolome identified 889 differential accumulated metabolites (DAMs) in three treated samples. The integrated transcriptomic and metabolomic analyses results showed that the DEGs and DAMs were enriched in photosynthesis, plant hormone signal transduction and flavonoid biosynthesis synthesis pathways. The ABA content of the C. adrienii leaves was significantly increased under shade. Therefore, the shading conditions led to changes in chlorophyll and abscisic acid (ABA), as well as the accumulation of flavonoids in C. adrienii, both of which were achieved by regulating genes involved in photosynthesis, plant hormone signal transduction and flavonoid biosynthesis molecular networks. Our results provide new knowledge for the molecular response and metabolic regulatory mechanisms of C. adrienii to shade stress, and valuable genetic resources for C. adrienii shade tolerance molecular breeding.

An 80 Gbps Integrated PDM‐OAM‐Enabled‐FSO Transmission for Implementing 5G Services Under Riyadh Weather Conditions

ABSTRACTThe surge in demand of high‐capacity wireless information transmission links has led to emergence of novel multiplexing techniques for free space optics (FSO) over the past few years. Two such important techniques are polarization division multiplexing (PDM) and orbital angular momentum (OAM) multiplexing. This article investigates the integration of PDM and OAM techniques in a FSO transmission system to enable 5G communication services in Riyadh City, Saudi Arabia. Four OAM beams () of 2‐polarization states of a single frequency laser beam are used to transport 10 Gbps data independently. A total of 80 Gbps net transmission rate is achieved. The visibility data for Riyadh city are collected from Saudi Meteorological Department and the attenuation coefficient is calculated using Kim, Kruse, and Al‐Naboulsi attenuation models. The performance of all the PDM‐OAM modulated signals is compared for the three‐attenuation models in terms of bit error rate, eye diagrams, and Q Factor of the signal at the receiver. The results show that using Kim and Kruse models, with attenuation of 0.62 and 0.64 dB/km, the maximum range of 3.8 km is achieved. This is, however, reduced to 2.4 km using Al‐Naboulsi model having attenuation of 2.03 dB/km with acceptable limits of Q Factor (∼6 dB) and BER (∼9).

Physiological and biochemical response of strawberry cv. diamond to nano zeolite soil application and cinnamic acid foliar application

The increasing global population and climate change are pressing challenges that necessitate innovative agricultural solutions to ensure food security. One promising approach is the use of nano fertilizers and foliar spraying techniques, which enhance nutrient delivery to plants. The purpose of this research was to examine how three different concentrations of nano zeolite (0, 30, and 60 mg L− 1) applied to the soil through irrigation and three different concentrations of cinnamic acid (0, 100, and 200 µM) applied topically affected the physiological and biochemical characteristics of strawberry (Fragaria × ananassa Duch.) cv. diamond, as well as the crop’s yield and quality of its fruits. A factorial system with three replications was used in the experiment, which was designed in a completely randomized design. According to the data, all features except stomatal conductivity were considerably impacted by soil application of nano zeolite and foliar spraying of cinnamic acid. Moreover, cinnamic acid (200 µM) spray combined with soil application nano zeolite (60 mg L− 1) decreased electrolyte leakage, transpiration rate, and malondialdehyde, while enhanced chlorophyll content, net photosynthesis rate, leaf dry matter, relative water content, fruit length and diameter, yield, and fruit quality parameters.

Efficient Nitrate Formation in Fog Events Implicates Fog Interstitial Aerosols as Significant Drivers of Atmospheric Chemistry.

Clouds and fogs, consisting of tiny water droplets formed by the condensation of water in supersaturated air, are vital in atmospheric chemistry, as they facilitate multiphase reactions. While measuring high-altitude cloud is challenging, fog as ground-level clouds offer a unique opportunity for direct observation. In this study, we explored radiation fogs in the North China Plain using an advanced aerosol-fog sampling system to measure the chemical and physical properties of both inactivated interstitial aerosols and activated fog droplet residues. Our findings revealed that efficient nitrate formation primarily occurred on fog interstitial aerosols rather than within fog droplets, with observed fog interstitial aerosol nitrate net production rates reaching up to 3.6 μg m-3 h-1. Box model simulations identified the hydrolysis of NO2 and N2O5 as key pathways for nitrate formation. NO2 hydrolysis was often overlooked in previous studies, contributing 40-79 and 57-76% to total nitrate production during nighttime and daytime fog periods. This oversight suggests that substantial nitrate formation through hydrolysis reactions involving interstitial aerosols may have been neglected. Our results highlight the need for further research into the chemistry of cloud and fog interstitial aerosols and their inclusion in atmospheric chemistry models.

Optimization and performance analysis of a hybrid system for hydrogen production: Thermodynamic, economic, and environmental perspectives

The increasing demand for sustainable energy solutions necessitates innovative systems that generate hydrogen, electricity, heating, and freshwater, addressing resource limitations and fossil fuel impacts. With a focus on green hydrogen for sustainable energy transformation, this study introduces a multi-generation system to enhance hydrogen production. A parametric and sensitivity analysis, including energy, exergy, exergoeconomic, and exergoenvironmental analyses, was conducted alongside a system sustainability analysis. The outputs of the considered basic system include net power, freshwater, and hydrogen production rates of 10.178 MW, 18.67 kg/s, and 1.727 kg/h, respectively. The system achieves an exergy efficiency of 50.30%, an energy efficiency of 42.58%, a capital cost rate of $112.87/h, an exergoenvironmental impact index of 0.9734, and a sustainability index of 2.012. Optimization using a genetic algorithm was performed across three scenarios. In one of these scenarios, specifically aimed at hydrogen production, the system achieved a production rate of 1.72 kg/h and a capital cost rate of $91.32/h.

Bioprospecting a Natural Antioxidant Peptide for Tomato Biostimulation Under Water Limitations: Physiological Approach

AbstractDrought causes major agricultural losses, threatening food security worldwide. Thus, innovative strategies have been explored to improve crop tolerance to drought. This work focused on one natural peptide (PpT-2) with antioxidant activity, unexplored in plant applications, to evaluate its effectiveness in mitigating drought effect on Solanum lycopersicum L. plants. For that, tomato plants were foliar sprayed with different doses of PpT-2 (0, 15 or 150 mg L−1) and exposed to water Stressed and UnStressed conditions. The plant growth, photosynthesis and oxidative stress-related parameters were evaluated. Plant treatment with PpT-2, mostly at the highest concentration, alleviated diverse effects induced by water restriction: stimulated CO2 assimilation; improved ΦPSII, Fv/Fm and Fv’/Fm’; amended net CO2 assimilation rate and water use efficiency; restricted H2O2 accumulation and lipid peroxidation; stimulated SOD activity. Under UnStressed conditions, PpT-2 induced some degree of stomatal closure, nevertheless without restricting CO2 availability for the non-photochemical processes of photosynthesis, besides of decreasing H2O2 content and CAT activity. Overall, PpT-2 application controlled H2O2 accumulation, and under water limitations improved both photochemical and non-photochemical processes of photosynthesis and promoted drought tolerance, underscoring its potential for managing drought stress in crop species.

Spatiotemporal Pattern of Vegetation Coverage and Its Response to LULC Changes in Coastal Regions in South China from 2000 to 2020

Analyzing vegetation coverage and land-use and land cover (LULC) characteristics helps to understand the interaction between human activities and the natural environment. The coastal regions of the Guangdong Province are economically active areas with frequent human activities, located in the advantageous natural environment of South China. This study analyzed the spatiotemporal characteristics of the normalized difference vegetation index (NDVI) and LULC from 2000 to 2020, to explore the response of NDVI changes to LULC changes. The results show that (1) the overall NDVI is relatively high, with a proportion of 85.37% to 89.48% of areas with higher coverage and above categories, mainly distributed in the east and west. Vegetation coverage showed an increasing trend. (2) The LULC in this area is mainly composed of forest land (46.5% to 47.5%) and cultivated land (30.7% to 33.4%), with forest land mainly distributed in relatively high-altitude regions and cultivated land mainly distributed in the plains. The changes in LULC from 2015 to 2020 were relatively significant, mainly due to the mutual transfer of cultivated land and forest land. In addition, built-up land continued to expand from 2000 to 2020, mainly in the Pearl River Delta. (3) The NDVI decreases come from the transfer of various types of land to built-up land, mainly in the Pearl River Delta region, while the NDVI increase comes from the stability and mutual transfer of cultivated land. The net contribution rate of forest land change to vegetation cover change is the most significant (−38.903% to 23.144%). This study has reference significance for the spatiotemporal characteristics of vegetation cover changes in coastal areas and their response to land-use changes, as well as coastal management and sustainable development.

The effects of simultaneous point gains and losses on human persistence.

Four experiments assessed the effects of simultaneous point gains and losses on human responding on a moving response button. Experiments 1 and 2 examined the effects of point loss arranged in variable-time (VT) and variable-interval (VI) schedules on persistence. For that purpose, a multiple schedule was in force. One component had point gains only, and the other had point gains and losses. The net reinforcement rate was equated across components by arranging greater point gains in the gains-plus-losses component. Increases in the speed of the moving response button disrupted responding during test sessions. No differential persistence between point-gains and point-gains-and-loss conditions was observed during Experiments 1 and 2. To ensure that point losses could function as punishers, Experiments 3 and 4 compared the effects of point loss arranged in fixed-ratio (FR) or VI schedules on response rate and persistence. The FR and VI point loss decreased the response rate during Experiment 3 but did not produce differential persistence in Experiment 4. These results suggest that point loss decreases response rate but does not weaken persistence more than gains strengthen persistence.