Source Level Research Articles

Tree seedling functional traits mediate plant-soil feedback survival responses across a gradient of light availability.

1. Though not often examined together, both plant-soil feedbacks (PSFs) and functional traits have important influences on plant community dynamics and could interact. For example, seedling functional traits could impact seedling survivorship responses to soils cultured by conspecific versus heterospecific adults. Furthermore, levels of functional traits could vary with soil culturing source. In addition, these relationships might shift with light availability, which can affect trait values, microbe abundance, and whether mycorrhizal colonization is mutualistic or parasitic to seedlings. 2. To determine the extent to which functional traits mediate PSFs via seedling survival, we conducted a field experiment. We planted seedlings of four temperate tree species across a gradient of light availability and into soil cores collected beneath conspecific (sterilized and live) and heterospecific adults. We monitored seedling survival twice per week over one growing season, and we randomly selected subsets of seedlings to measure mycorrhizal colonization and phenolics, lignin, and NSC levels at three weeks. 3. Though evidence for PSFs was limited, Acer saccharum seedlings exhibited positive PSFs (i.e., higher survival in conspecific than heterospecific soils). In addition, soil microbes had a negative effect on A. saccharum and Prunus serotina seedling survival, with reduced survival in live versus sterilized conspecific soil. In general, we found higher trait values (measured amounts of a given trait) in conspecific than heterospecific soils and higher light availability. Additionally, A. saccharum survival increased with higher levels of phenolics, which were higher in conspecific soils and high light. Quercus alba survival decreased with higher AMF colonization. 4. We demonstrate that functional trait values in seedlings as young as three weeks vary in response to soil source and light availability. Moreover, seedling survivorship was associated with trait values for two species, despite both drought and heavy rainfall during the growing season that may have obscured survivorship-trait relationships. These results suggest that seedling traits could have an important role in mediating the effects of local soil source and light levels on seedling survivorship and thus plant traits could have an important role in PSFs.

Source Spectra of Pg and Lg Waves from North Korean Nuclear Tests Estimated Using a Nonmodel-Based Approach

ABSTRACT In this article, we demonstrate that source spectra for regional seismic waves generated by an underground explosion may be uniquely extracted using a simple linear regression method between the geometrical spreading corrected displacement spectra and epicentral distances as long as the recording stations are well distributed in distances. Using this method, source spectra of Pg and Lg waves from North Korean nuclear tests conducted between 2009 and 2017 are estimated, respectively, and are compared to test the conjecture of Fisk (2006) as well as to determine the relative size between the seismic moment of Lg waves and that of compressional waves. For a specified explosion, the resultant Pg and Lg source spectra approximately have equal low-frequency source level. Based on this result, it is estimated that for the explosions seismic moment of Lg waves would be about 35% of that of compressional waves. In addition, it is shown the Fisk conjecture approximately stands, as for a specified explosion the observed Pg and Lg source spectra share the same manner of high-frequency rolloff as f−2, the source corner frequency of Lg waves is smaller than that of Pg waves by a factor of about 1/3, and the Pg source spectrum exhibits a prominent overshoot, whereas it is not obvious in corresponding Lg source spectrum. The new method for source spectra estimation may have a promising application prospect in monitoring studies. As an example, it is shown that the yield and even buried depths of the North Korean nuclear explosions may be reasonably estimated by fitting the observed Pg source spectra using an MM71- (Mueller and Murphy, 1971) and DJ91 (Denny and Johnson, 1991)-based hybrid source model suggested by Ford and Walter (2013).

Design and realization of directivity adjustable ring transducer

In this paper, a directional segmented ring transmitting transducer, which can radiate sound waves in any horizontal region, has been developed. First, we introduce the structure of the segmented ring transducer and the characteristics of its radiation sound field, investigate the transmitting beam pattern control method based on the modal synthesis, and propose orthogonal beam pattern functions to adjust steering angles. Then, the three-dimensional finite element model of the segmented ring transducer is established, and the amplitude and phase of sound pressure excited by the first three modes, respectively, are calculated as a function of the frequency. We can combine each mode to obtain the desired beam patterns, and simulate the transmitting beam patterns steering to different directions. Finally, we manufacture the segmented ring transducer and measure its transmitting directivity in an anechoic water tank, and the first three modes are also calibrated according to the measured sound pressure. The experimental results show that the beam pattern synthesized by the first two modes has a 3 dB down beam width of about 156◦ at 15 kHz after calibration, and the maximum source level is approximately 24 dB higher than the minimum. The −3 dB beam width synthesized by the first three modes is about 84◦ at 17 kHz after calibration. In addition, we also carry out the experimental test on the proposed beam control method, and the driving-voltage weighting vectors are designed to obtain good transmitting beam patterns steering to different angles.

Norway spruce extracts (NSEs) as bioactive compounds in novel feeds: Effect on intestinal immune-related biomarkers, morphometry and microbiota in Atlantic salmon pre-smolts

Compounds from woody biomass are promising candidates as feed additives to improve fish health and welfare of Atlantic salmon (Salmo salar) during the productive cycleng. Thus, conidendrin- and isorhapontin-based extracts (NSEs) from Norway spruce (Picea abies) were evaluated at different levels in a four-week trial. A commercial-like diet (D1) was supplemented with 0.2% of a commercial β-glucan (D2) or with NSEs at 0.02%, 0.1% and 0.2% (D3-D8). No significant differences were found in growth, intestinal morphometry and microbiota at the genus level. Immune-related biomarkers in distal intestine from D5 and D6 indicated an activation of a pro-inflammatory response by the up-regulation of il1b, as in D2. Interestingly, isorhapontin-based extract at higher inclusion level (D8), showed a down-regulation of both pro- and anti-inflammatory- genes, suggesting maintenance of homeostasis. These results showed the importance of source and inclusion levels of bioactive compounds on the regulatory balance associated with fish immune response.

Effect of LED Light Frequency on an Object in Terms of Visual Comfort

Light emitting diodes (LEDs) play an essential role in lighting, and green earth activities because of their high efficiency, longevity, and reduction of carbon dioxide emissions during illumination. However, the brightness level of LED light sources must be adjusted appropriately for the backlight source or illumination; therefore, pulse amplitude modulation (PWM) is a commonly used method of LED control. This article experimentally investigated human interaction with the visual comfort effect of the light obtained using different PWM frequencies on an object in a sensor-based intelligent lighting system. Critical light frequencies are vital for the eye to distinguish light stimuli according to time. Histograms of the object were created according to the light frequency, and the results are discussed. The eye’s response to light frequencies changing over time is important for visual comfort, and examining light frequencies in the range of 25–250 Hz was sufficient to conclude the study. It has been experimentally shown that light frequencies around 160 Hz, and above this value provide visual comfort.

Observation and Modelling on the Shipping Noise in Shallow Waters with Complex Islands and Reefs of the East China Sea

The impact of the noise radiated from merchant ships on marine life has become an active area of research. In this paper, a methodology integrating observation at a single location and modelling the whole noise field in shallow waters is presented. Specifically, underwater radiated noise data of opportunistic merchant ships in the waters of Zhoushan Archipelago were collected at least one day in each month from January 2015 to November 2016. The noise data were analyzed and a modified empirical spectral source level (SSL) model of merchant ships was proposed inspired by the RANDI-3 model (Research Ambient Noise Directionality) methodology. Then combining the modified model with the realistic geoacoustic parameters and AIS data of observed merchant ships, the noise mappings in this area were performed with N×2D of Normal Mode calculations, in which the SSL of each ship was estimated using the modified model. The sound propagation at different receiving positions is different due to the shielding effect of islands and bottom topography. The methodology proposed in this paper may provide a reference for modelling shipping noise in shallow waters with islands and reefs.

Directional and amplitude characteristics of pulsed call sequences in captive free-swimming Pacific white-sided dolphins (Lagenorhynchus obliquidens).

We investigated the directional properties and gain control of a pulsed call sequence that functions as a contact call in Pacific white-sided dolphins (Lagenorhynchus obliquidens). The pulsed call sequences were stereotyped patterns composed of three or more pulsed call elements and were collected from two dolphins, separated into adjacent pools, and allowed to swim freely. Eight hydrophones and an overhead camera were used to determine the positions and directions of the participants. The mean peak frequency and source levels were 8.4 ± 4.4 (standard deviation)-18.7 ± 12.7 kHz and 160.8 ± 3.8 to 176.4 ± 7.9 dB re 1 μPa (peak-to-peak), respectively, depending on the element types. The elements were omnidirectional, with mean directivity index of 0.9 ± 3.4 dB. The dolphins produced sequences, regardless of their relative position and direction to the lattice, leading to the adjacent pool where the conspecific was housed. They increased the amplitude by 6.5 ± 4.6 dB as the distance from the caller to an arbitrary point in the adjacent pool doubled. These results suggest that callers broadcast pulsed call sequences in a wide direction to reach dispersed conspecifics. However, they can adjust the acoustic active space by controlling the source levels.

Influence of the nature of lamp on model parameters of PV modules operating in an indoor environment

A growing body of research on energy harvesting has revealed the need for effective tools, models, and methods for designing indoor light harvesting systems. In general, PV modules are represented electrically by circuits which include Single Diode Models (SDM), Double Diode Models (DDM), and Triple Diode Models (TDM). PV modules' performance can be understood by appropriately determining the parameters of these models. In order to estimate these parameters, datasets are usually measured experimentally by electrically lighting PV modules or placing them under artificial light. The main goal of this study is to analyse the effects of the nature of light source and illumination level on different model parameters of PV modules. Three PV modules of same power and different cell technology are placed under three commonly used lamps at same illumination levels. The data measured under these conditions is used with the Grey Wolf Optimization algorithm to estimate different model parameters. The results indicate that different values are obtained for shunt and series resistances for the same PV module placed under different lamps and at same illumination level. These parameters are equally seen to vary differently when the illumination level is changed.

317 Awardee Talk: Functional Roles of Phytase and Xylanase for Nursery Pigs and Broiler Chickens

Abstract The objective of this research was to investigate the functional roles of phytase and xylanase in nursery pigs and broiler chickens. These enzymes have been widely studied and have shown consistent results improving nutrient digestibility and growth performance. However, recent studies have raised the hypothesis that phytase and xylanase could also have potential effects on intestinal and bone health, and intestinal microbiota. The first study studied at the effects of a bacterial 6-phytase on nutrient digestibility and retention of nursery and growing pigs. The results showed that supplementing a bacterial 6-phytase in pig diets can be a potential alternative for reducing high levels of inorganic phosphorus sources while still increasing the digestibility and utilization of phosphorus by the animals. The second study investigated the efficacy and optimal level of a bacterial 6-phytase supplemented beyond traditional dose levels on bone and intestinal health, nutrient digestibility, and growth performance of nursery pigs. The results revealed that the supplementation of the bacterial 6-phytase enhanced bone health, nutrient digestibility, and growth performance in nursery pigs. The third study aimed to determine the effects of phytase supplementation on the intestinal microbiota and morphology, bone health, nutrient digestibility, and growth performance of broiler chickens. The results showed that phytase supplementation had potential benefits on the microbiota by reducing potential harmful bacteria and increasing beneficial bacteria. Additionally, phytase had positive effects on bone health, intestinal morphology, and nutrient digestibility of broiler chickens. The fourth study examined the functional roles of xylanase on the intestinal health and growth performance of nursery pigs. The results showed that xylanase supplementation had beneficial effects on intestinal health by reducing the digesta viscosity, the relative abundance of potentially harmful bacteria, and the oxidative stress in the jejunal mucosa. All of these factors collectively reflected in improvements on the intestinal morphology, nutrient digestibility, and growth performance of nursery pigs. In conclusion, the results of these studies reaffirmed the benefits of phytase and xylanase related to nutrient digestibility and growth performance in nursery pigs and broiler chickens, as well as showed potential benefits on intestinal health and microbiota of the animals. Supplementing these enzymes could also contribute to a reduction in feed costs and environmental concerns associated with a poor hydrolysis and breakdown of antinutritional factors in animal diets.

Biochar-Based Phosphorus Recovery from Different Waste Streams: Sources, Mechanisms, and Performance

Elevated phosphorus (P) levels in water sources can result in eutrophication, which in turn causes environmental pollution and adversely affects aquatic ecosystems. Additionally, there is a risk of P depletion due to intensive exploitation and utilization. Therefore, the sustainable and efficient use of P, waste reduction, and P recovery from waste sources have become urgent priorities. This article aims to provide the most current assessments of the P regeneration process and its origins within waste and wastewater. This work also evaluates P recovery, as to its mechanisms, influencing factors, and performance. Moreover, the review presents comprehensive results from pilot and full-scale applications of P recovery. Further perspectives are analyzed, including economic feasibility, potential environmental impacts, research needs, and opportunities for improving P recovery.

Attitudes toward the integration of nutritional assessment and counseling in the framework of physical therapy: a cross-sectional survey

BackgroundAs the field of physical therapy increasingly acknowledges the integral role of nutritional assessment and counseling, revisiting this subject is essential due to limited updated information regarding this topic. Furthermore, it is crucial to investigate the factors that may influence physical therapists’ attitudes toward integrating nutritional assessment and counseling into their physical therapy practice. The study’s primary aim was to explore the attitudes of registered physical therapists in Israel toward incorporating nutritional assessment and counseling into their clinical practice. We also explored the relation between personal and professional characteristics of physical therapists and their attitudes.MethodsAn anonymous nationwide online self-report survey was conducted. It included three sections: personal and professional background characteristics, self-reported level of nutritional knowledge and sources of nutritional knowledge, and attitudes toward incorporating nutritional assessment and counseling into practice. Descriptive statistics were calculated for all outcome measures. The total score of the attitude statements was compared between different groups of participants. Multiple linear regression analysis was used to predict positive attitudes.ResultsThe study included 409 physical therapists. The attitude score was 19.78 (2.53) of 25, indicating a positive attitude. A majority (67%) reported that they did not acquire knowledge regarding nutrition during their entry-level studies or in other formal settings (63%). The three primary sources of nutritional information for the participants reported were the Internet (87.0%), registered dietitian (70.0%), and professional, scientific journals (36.0%). Prior knowledge acquired during entry-level physical therapist studies and clinical experience of ≥ 13 years significantly predicted positive attitudes (β = 0.17, β = −0.13, respectively).ConclusionRegistered physical therapists held a positive attitude toward incorporating nutritional assessment and counseling into their clinical practice. Two background professional characteristics were predictors of positive attitudes. Accordingly, there is need to appropriate formal education regarding nutritional issues. Further studies are required to explore the actual integration of nutrition into the physical therapy framework.

Meta‐analytic assessment of physiological markers for decapod crustacean welfare

AbstractDecapod crustacean welfare is not only an ethical consideration for legislative purposes. Under culture and fishery settings, poor environmental conditions and operator practices can cause stress, which compromises the immune system and increases the risk of disease. For finfish, there are established environmental and animal (group, individual) welfare indicators. This is not the case for crabs, lobsters or shrimp. While environment‐based indicators like temperature, pH and oxygen levels are easily transferable, there is no consensus for a common measure of stress to monitor welfare in decapod crustaceans. To address this shortcoming, we conducted a meta‐analysis of the primary literature to test for relationships between haemolymph (blood) condition, for example, levels of glucose, L‐lactate, haemocytes (n = 8), and sources of physical stress, for example, handling, trawling, emersion and transport (n = 12). Despite variations in effect sizes (n = 459), generalised linear mixed models repeatedly ranked L‐lactate (followed by urea and glucose) as the most significant physiological predictor of stress in the haemolymph, with trawling followed closely by emersion as the most impactful stressors. Duration post (stress) exposure, sex (male, female), water temperature and moult stage (pre‐, inter‐, post‐moult) were not associated significantly with stress prediction using the selected biochemical and cellular parameters, however, moult status was undefined in ~48% of literature sources and should be interpreted with caution. We present evidence that quantitating L‐lactate levels in the haemolymph represents a physiologic operational welfare indicator of decapod crustaceans, which complements existing condition/vigour indices.

Emotions and Education: Media Representations in the Discourse on School Closures in Polish and British Internet Portals

The aim of the article is to present the representations of emotions (happiness, anger, sadness, fear, worry, stuckness, compassion, dumbing, stagnation, humiliation, sense of guilt, hope, hate, sense of privilege solidarity, boredom, banality), neighbourly solidarity in the texts of the opinion-forming portals Polityka (PL) and The Spectator (UK), referring to school closures due to the Covid-19 pandemic, and their media representations in the public (the perspective of a teacher, school headmaster, member of the government, expert) and private domain (the perspective of a student and parent), in the processual approach (a catalogue of events), in the context of technological changes (distant learning), as well as socio-cultural (human relationships, domestic violence) and economic (social benefits) contexts.
 Our hypothesis is that, in line with the concept of the culture of fear by Frank Furedi, the way the internet content is created and construed is supposed to evoke the emotion of fear. We performed a quantitative and qualitative analysis of the content of 78 articles published in Polityka and 12 in The Spectator, between 1 March 2020 and 30 July 2020, found with the use of a search engine.
 We observed at least three levels of information sources on emotions in the studied groups: the main character of the article, the one who experiences emotions (perspective of the sender); the author/editor of the article, who does evaluation and interpretation (perspective of the gate-keeper) and the reader (perspective of the addressee). On these levels, emotions can result from their literal identification; from an interpretation of a given situation, from the situational context (contextual emotions) and from the non-verbal clues and physical reactions of the organism.
 The hypothesis was partially confirmed. Despite the fact the school closures, as represented by the media, generates mostly the emotion of fear, the emotion prevalent in the discourse on the consequences of school closures and on the evaluation of remote education is sadness (Polityka) and compassion (The Spectator). However, the dominant emotion, both in the public-private and public domain, is the one of sadness.

An investigation of the assumed efficacy of methionine hydroxy analogue compared to DL-methionine by measuring growth performance, carcass traits, and GHR and IGF-I expression in broilers

This experiment was conducted to investigate the assumed efficacy of 65% on the product basis of methionine hydroxy analog (OH-Met, 88% aqueous solution of DL-2-hydroxy-4-(methylthio) butanoic acid) relative to DL-methionine (DL-Met) in broiler chickens. A total of 792-day-old male chickens were randomly allotted to 7 dietary treatments consisting of a methionine deficient-basal diet based on corn-soybean meal and 6 different diets obtained by supplying the basal diet with methionine at 3 levels (25, 100 and 125%; levels of addition relative to the required amount of additional Met to meet SID Met + Cys requirements) from either DL-Met or OH-Met at a ratio of 65:100 (DL-Met to OH-Met on a product basis) in the corresponding treatments. Regardless of the source, methionine supplementation enhanced (p < .05) growth performance, carcase and breast meat yield. Supplemental level and the source of Met had no significant effect on the proximate chemical composition of breast meat (p > .05). Comparison of effects of OH-Met and DL-Met supplemented at 100–65% weight ratio revealed no differences at any Met + Cys level and for performance criterion confirming the applied concept. Expression of growth hormone receptor (GHR) mRNA, which showed a positive correlation with body weight gain, carcase yield and breast percentage, in broiler liver significantly increased with 100% and 125% relative addition of DL-Met, while only 100% of OH-Met addition did (p < .05) when compared to the basal diet. The expression of the insulin-like growth factor-I (IGF-I) gene was not significantly affected by either Met source or supplementation level. In conclusion, our data indicated that DL-Met can be substituted with a 1.54 times higher amount of OH-Met in corn-soybean meal based broiler diets.

Nature-Based Solution to Eliminate Cyanotoxins in Water Using Biologically Enhanced Biochar.

Climate change and high eutrophication levels of freshwater sources are increasing the occurrence and intensity of toxic cyanobacterial blooms in drinking water supplies. Conventional water treatment struggles to eliminate cyanobacteria/cyanotoxins, and expensive tertiary treatments are needed. To address this, we have designed a sustainable, nature-based solution using biochar derived from waste coconut shells. This biochar provides a low-cost porous support for immobilizing microbial communities, forming biologically enhanced biochar (BEB). Highly toxic microcystin-LR (MC-LR) was used to influence microbial colonization of the biochar by the natural lake-water microbiome. Over 11 months, BEBs were exposed to microcystins, cyanobacterial extracts, and live cyanobacterial cells, always resulting in rapid elimination of toxins and even a 1.6-1.9 log reduction in cyanobacterial cell numbers. After 48 h of incubation with our BEBs, the MC-LR concentrations dropped below the detection limit of 0.1 ng/mL. The accelerated degradation of cyanotoxins was attributed to enhanced species diversity and microcystin-degrading microbes colonizing the biochar. To ensure scalability, we evaluated BEBs produced through batch-scale and continuous-scale pyrolysis, while also guaranteeing safety by maintaining toxic impurities in biochar within acceptable limits and monitoring degradation byproducts. This study serves as a proof-of-concept for a sustainable, scalable, and safe nature-based solution for combating toxic algal blooms.

Comprehensive evaluation of hydro-chemical processes, suitability, health risks, and sources of groundwater contamination using compositional data analysis, Nizampur basin, Pakistan

This study aimed to evaluate the level of contamination, health risks, hydro-chemical processes, and sources of contaminants in the groundwater of the Nizampur basin, northwestern Pakistan. Forty-eight (n = 48) groundwater samples from predefined locations were collected and analyzed using the standard procedure for a total of 13 parameters. Statistical techniques in the compositional data analysis perspective were used for the identification of sources. The results showed that TDS, Turbidity, SO4, and NO3 concentrations surpassed the limits in 44, 29, 25, and 48% of samples, respectively. The nitrate pollution index indicated that 48% of the samples were contaminated with nitrates, while the composite index PIG showed that only 22% of the samples indicated low pollution. A close association between the land use/land cover of the study area and NO3 contamination was observed. In general, the groundwater of the region could be categorized as fresh-very hard water (87.5%), the major hydro-chemical facies were, Ca–Mg–HCO3, followed by mixed Ca–Mg–Cl and Ca–Cl facies. The Van Wirdum diagram showed that groundwater was mainly influenced by rock weathering and profound human impact. Similarly, it was assessed using chloro-alkaline indices that reverse ion exchange is a governing hydro-chemical process. NO3 concentrations in the area have the potential to cause non-cancer ailments in 75% and 47% of the samples in children and adults respectively. Based on the assessments made using the compositional data analysis it was inferred that NO3, SO4, Cl, and Turbidity originated from human sources, while the rest of the parameters have natural/geogenic sources.

Is There a Convergence between the Food Classification Adopted by Food-Based Dietary Guidelines and Food Science and Technology?

The World Health Organization (WHO) proposed the dietary guidelines presented as the Food-based Dietary Guidelines (FBDG). The FBDG classify foods according to their origin, nature, nutrient source, food group, and processing level. Food science and technology (FST) ranks food according to its origin, perishability, nutrient source, processing, food group, and formulation. This paper aimed to compare the convergence points for food classification according to the FBDG and FST. This study was carried out in two phases. The first step was identifying the Food-Based Dietary Guidelines (FBDG). For each of the FBDG, food items were grouped as fruits, vegetables, cereals, sugars, fat and oils, legumes, foods from animals, dairy products, and others. The second step aimed to identify and describe the different food classification systems. The search was performed on PubMed®, Science Direct, and Web of Science and websites of international organizations such as the Food and Agriculture Organization of the United Nations (FAO), the World Health Organization (WHO), and the Codex Alimentarius. Our results show that the points of convergence between the classifications were the classification in terms of origin (animal and vegetable), nutrient sources, and food groups. However, inconsistencies were observed for the distribution of food items in each group in the 98 surveyed FBDG. As for nature, there was a convergence for in natura, minimally processed, and processed foods. However, the criteria adopted for minimally processed and processed foods described in the FBDG differ from those considered by the FST. FST also does not recognize the classification of foods concerning the level of processing.

The National Water Resources Policy and Water Management: Considerations about the Rural Context of the Cantareira System

Purpose: The National Water Resources Policy established foundations and instruments for the management of water resources in Brazil. Despite being considered one of the most advanced internationally, its effectiveness is questioned for water management in rural contexts where small users predominate. The article presents elements of water management conducted by rural landowners, seeking to analyze how these elements approach or distance themselves from the foundations and instruments of the National Water Resources Policy. For this purpose, semi-structured interviews were carried out with 151 rural landowners who use water resources in the context of the supply sources of the Cantareira Water Production System. The results indicate that the water sources accessed by users are the central reference that supports decisions on local water management, which distances itself from the watershed as a management unit, as proposed by law. Not based on a scientific conception, users mobilize specific indicators to determine the quality of the water consumed. Perceptions of the private domain and common good surrounding water sources do not fully align with the understanding of water as a public good. Furthermore, the notion of free access to and use of water also distances itself from any intention to charge for water in rural areas. It is concluded that the foundations and instruments of the National Water Resources Policy are not able to promote the management of water resources at the level of small sources and users, and that the perceptions and management practices of these users are far from what is established by law. The objective of the article is to present elements of water management conducted by rural landowners, seeking to analyze how these elements approach or distance themselves from the foundations and instruments of the National Water Resources Policy. Method/design/approach: The research is of a qualitative nature, of a descriptive nature, having been carried out empirical research. For the empirical research, semi-structured interviews were carried out with 151 rural landowners who use water resources in the context of the supply sources of the Cantareira Water Production System. Results and conclusion: The results indicate that the water sources accessed by users are the central reference that supports decisions on local water management, which distances itself from the hydrographic basin as a management unit, as proposed by law. Not based on a scientific conception, users mobilize specific indicators to determine the quality of the water consumed. Perceptions of the private domain and common good surrounding water sources do not fully align with the understanding of water as a public good. Furthermore, the notion of free access to and use of water also distances itself from any intention to charge for water in rural areas. Research implications: From the analysis, it is highlighted that the fundamentals and official instruments of water resources management cannot influence the water management that occurs at the level of small rural users. The main implication of the study is to stimulate reflection on the need to build a policy that takes into account elements of local water management, seeking full management of water resources. Originality/value: The study seeks to contribute to the improvement of water resources management, in terms of local management aspects. The ways of acting of rural landowners need to be recognized, understood and valued, so it will be possible to promote sustainable water management in one of the most critical contexts for water security in the country.

Measurement and factor analysis of carbon neutrality development level in eastern China.

The Chinese government has officially announced that China's carbon dioxide emissions will reach to peak before 2030 and achieve carbon neutrality before 2060. Based on the carbon neutrality development of 12 provinces and cities in eastern China from 2010 to 2019, this paper constructs an evaluation index system, and it uses the entropy weight method and coefficient of variation method to measure the carbon neutrality development level in the eastern China. The results show that from 2010 to 2019, the changes of carbon source level in 12 provinces and cities in the eastern China are lower than the changes in carbon sink level, and the changes of carbon source and sink level in most provinces and cities show the increasing trend. Spatially, the carbon neutral development level shows the differentiation characteristics of "low in the middle, high in the north and south." The main factors affecting the carbon neutrality level of eastern provinces and cities include policy, economic development and industrial structure, energy intensity and structure, urban development, and population size ecological environment. High-value areas are mainly distributed in Heilongjiang Province, Jilin Province and Fujian Province. Low-value areas are mainly distributed in Jiangsu Province and Shandong Province. Eastern China still needs to strengthen its emphasis on low-carbon policies. For Shandong Province, Jiangsu Province, and Hebei Province, policies should be introduced to reduce carbon sources, accelerate their industrial upgrading, and optimize their energy use structure. For Beijing City, Shanghai City, Heilongjiang Province, and Jilin Province, policies should be introduced to develop carbon sinks while maintaining their low carbon source levels. For Beijing City and Shanghai City, policies related to green and low-carbon technologies should be introduced to promote the development of carbon sink capacity through low-carbon technologies in limited urban areas.

Integration of a Gamma-Type Stirling Engine with LPG Cooking Stove for Micro-Scale Combined Heat and Power Generation

The Stirling engine is one of the most versatile micro-scale prime movers for combined heat and power applications, adaptable to different levels of heat sources. This study started a unique journey that included developing, experimenting, and analyzing the Gamma-type Stirling engine. Notably, the engine design ingeniously harnesses heat from a customized cooking stove burner powered by liquefied petroleum gas. The engine fabrication resulted in a compression ratio 2.014, accommodating a volumetric capacity of 181 cc. The Stirling engine test used air as the working gas, and the initial conditions were at atmospheric pressure. Stirling engine performance was analyzed using an ideal thermodynamic cycle model and burner efficiency using the water boiling method. The modified burner attains an average temperature of 699.5°C, producing a burner power output of 5.702 kW and a thermal efficiency of 32.7% or around 1.867 kW of heat for operating the engine and cooking activities. Simultaneously, tests of the Stirling engine revealed an average air temperature difference of 146.2°C between the expansion and compression phases. The flywheel rotation speed ranges from 158 to 369 rpm. During testing, the Stirling engine obtained an average thermal efficiency of 31.08%, accompanied by an ideal power spectrum ranging from 0.3 W to 42.6 W. The highlight of this study was the maximum pressure achieved at the end of the heat absorption stage, recorded at 296.1 kPa. Importantly, these findings underscore the promising potential of micro-Combined Heat and Power systems. Integrating the gamma-type Stirling engine with the LPG stove represents novelty and paves the way for further development and advancement in sustainable energy solutions.