Low Rate Applications Research Articles

Profitable, low-emission nitrogen application strategies in Western Australian dryland cropping

Context Australian grain producers may need to report their farm greenhouse emissions. Accordingly, nitrogen fertiliser application strategies will need to include consideration of their environmental as well as economic impacts. Aims We aim to identify the nitrogen application strategies suited to dryland cropping in Western Australia that are highly profitable and that generate lower emissions. Methods Simulation modelling is used to examine the gross margins and emissions associated with four broadly different nitrogen strategies at 14 locations in the grainbelt of Western Australia for different frequencies of cropping. Key results Strategies that generate high gross margins and moderate emissions often focus on maximising the gross margin of crop production, and apply a decile 5 view of unfolding seasonal conditions. A similarly useful strategy applies nitrogen in a fixed ratio where a tonne of expected cereal receives 45 units of nitrogen from various sources, and a tonne of expected canola receives 70 units of nitrogen from various sources. Where a farmer prefers to apply a constant rate of nitrogen, then exceedingly high or low rates of application should mostly be avoided, either for economic or for environmental reasons, with the better option at many locations being to apply 50 or 75 kg N/crop ha. Conclusions A few preferred nitrogen application strategies are suggested to be applicable to dryland cropping in the study region. The strategies achieve high profits and generate moderate or low emissions. Implications Selection of highly profitable and lower emission nitrogen application strategies across the study region can deliver sizeable economic and environmental benefits.

Soil and rhizosphere bacteriobiome of wheat under combined humate and fly ash application

The aim of the study was to exmine the effct of low rate of potassium humate application with and without fly ash (FA) on wheat roots rhizosphere bacteriobiome. Location and time of the study. The microplot field experiment was conducted in three replicates in randomized design in 2022 in Novosibirsk (Russia). Methods. Soil physical and chemical properties were determined by commonly used methods. Bacteriobiome structure and diversity were estimated by 16S rRNA genes (V3-V4 region) by metabarcoding. Results. The study revealed large bacteriobiome diversity: on average 2472 and 2330 operational taxonomic units (OTU) in bulk and rhizosphere soil< respectively. Overall 9120 OTE were found, belonging to 929 genera, 438 families, 416 orders, 104 classes and 37 phyla. A quarter of the total OTUs number belonged to the Proteobacteria phylum; Actinobacteria phylum ranked second in OTUs number (10%), whereas Firmicutes, Bacteroidetes and Acidobacteria each accounted for 8% of the total OTUs number. The Actinobacteria dominated in the relative abundance of the total number of sequence reads (38–41%), with Proteobacteria (25–28%) and Acidobacteria (10–13%) following. The treatment with potassium humate without fly ash did not influence the relative abundance of genera in the bulk soil, but increased twofold the relative abundance of the genus when combined with FA. In the rhizosphere soil bacteriobiome potassium humate without FA increased the Nocardioides relative abundance 1.8 times, whereas in combination with FA increased Sphingomonas and decreased Spartobacteria_gis relative abundance. Conclusions. Potassium humate treatment at a low rate resulted in small, but positive changes in soil and rhizosphere bacteriobiome despite the huge bacterial diversity, inherent for practically any soil, including the one used in this study. The effect of exogenic humate treatment involves a complex of various mechanisms, and detailed physiological and biochemical studies and meta-analysis of the published data are needed to understand the effect of low rate humate application on soil, plans and microorganisms.

Multispecies forages in the Australian dairy feedbase: is there a biological business case?

This review considers the potential role of multispecies swards in de-risking Australian dairy systems that currently rely heavily on monocultures of perennial ryegrass and high rates of inorganic nitrogen application to be productive. Recent trends in increasing inorganic nitrogen fertiliser prices, societal pressure for increased environmental sustainability of farming practices, coupled with variable and extreme weather events have renewed interest for functionally diverse pasture mixtures. Evidence from the latest international studies either for or against the purported benefits of multispecies swards (e.g. productive, resilient, and environmentally positive) is examined. There is an ever-growing body of evidence confirming that species richness can promote high levels of productivity at low or zero rates of nitrogen fertiliser application, often with increasingly positive effects as species richness increases. However, results within and between different levels of species richness are not always consistent, suggesting that not all multispecies swards will perform alike, even at a constant level of functional diversity. A multitude of other factors is presented that interact to determine the success of one multispecies sward over another. These include soil type and fertility, species choice, functional group proportions, sward management under either grazing or cutting, fertiliser regimes, and grazing management practices. It was concluded that this complexity gives rise to a need for further research into the biological mechanisms behind multispecies mixtures to determine the factors, other than simply species richness, that will guarantee success as more farmers inevitably search for alternatives to perennial ryegrass pasture in the Australian dairy farming industry.

Inclusion and equity: Experiences and dilemmas of disability resource centers at world-class universities

The disability resource centers (DRCs) of world-class universities play a central role in achieving the goal of promoting inclusion and equity in higher education. To provide a reference for the development of inclusive education in China’s double first-class universities, the DRCs of the top 10 universities were selected as typical cases to analyze their experiences and dilemmas. Regarding service mechanisms, DRCs aimed to ensure equitable access so that students with disabilities (SWD) could fully and holistically participate in universities, thereby improving inclusion on campus. In addition, DRCs established official websites as a service platform and developed clear service procedures and grievances to ensure the quality of service. Regarding service content, DRCs emphasized enhancing the disability awareness of campus members and provided support and services for SWD in their study, life, and employment to ensure that SWD could receive high-quality higher education. However, DRCs also suffered from dilemmas of low service application rates, flawed service mechanisms, and controversial service quality. Accordingly, suggestions and implications are proposed to improve inclusion and equity in China’s double first-class universities, including establishing a collaborative disability service system with DRCs as the core, optimizing the service mechanism, and providing personalized and diversified support service content.

Deep Generative Learning Models for Cloud Intrusion Detection Systems.

Intrusion detection (ID) on the cloud environment has received paramount interest over the last few years. Among the latest approaches, machine learning-based ID methods allow us to discover unknown attacks. However, due to the lack of malicious samples and the rapid evolution of diverse attacks, constructing a cloud ID system (IDS) that is robust to a wide range of unknown attacks remains challenging. In this article, we propose a novel solution to enable robust cloud IDSs using deep neural networks. Specifically, we develop two deep generative models to synthesize malicious samples on the cloud systems. The first model, conditional denoising adversarial autoencoder (CDAAE), is used to generate specific types of malicious samples. The second model (CDAEE-KNN) is a hybrid of CDAAE and the K -nearest neighbor algorithm to generate malicious borderline samples that further improve the accuracy of a cloud IDS. The synthesized samples are merged with the original samples to form the augmented datasets. Three machine learning algorithms are trained on the augmented datasets and their effectiveness is analyzed. The experiments conducted on four popular IDS datasets show that our proposed techniques significantly improve the accuracy of the cloud IDSs compared with the baseline technique and the state-of-the-art approaches. Moreover, our models also enhance the accuracy of machine learning algorithms in detecting some currently challenging distributed denial of service (DDoS) attacks, including low-rate DDoS attacks and application layer DDoS attacks.

Design of High-Performance Intelligent WSN based-IoT using Time Synchronized Channel Hopping and Spatial Correlation Model

Wireless Sensor Network (WSN) is one of the most significant contributors to the Internet of Things (IoT), and it plays a significant role in the lives of individuals. There are three main problems in the design of traditional WSN based-IoT. First problem about data; the WSN transmits a huge volume of data to the IoT for processing. The second problem is the energy; since sensor nodes rely on their limited battery, conserving energy is crucial, and the third problem about efficiency of transmission. This paper presents new WSN based IoT framework that integrate important techniques to solve these problems; To increase the effectiveness of data processing and storing, the intelligent Adaptive Boosting stochastic algorithm is applied. IEEE 802.15.4e time slotted channel hopping (TSCH) protocol is used because it has the benefits such as collision-free transmission and multi-hop transmission. Data reduction at the Gateway (GW) level of the network is achieved through spatial correlation between sensors with the goal of conserving energy. Principle idea of this new framework is to identify the advantages of integrating the important techniques; intelligent Adaptive Boosting Stochastic diffusion search algorithm, TSCH, and Special correlation model. As a result, the proposed framework can thereby satisfy the need for a long battery life of low-rate applications and at the same time, the need for high throughput for high-rate uses also for testing it in achieved efficient classification of data, the important performance measures are used.

RANCE: A Randomly Centralized and On-Demand Clustering Protocol for Mobile Ad Hoc Networks

LEACH-like clustering protocols focus mainly on the low-power, low-rate, and low-wakeup network applications, and work in a multiround clustering strategy that causes frequent handovers of cluster heads (CHs), thus less support for real-time services that require stable cluster topologies. Besides, these protocols are faced with respective drawbacks, such as suboptimality of selected heads, costly node-base station (BS) energy overheads, lack of runtime cluster maintenance, etc. This article proposes RANCE, a randomly centralized and on-demand clustering protocol, aiming at prolonging nodes’ clustered time to support internodes collaboration while being energy efficient in mobile ad hoc networks. First, RANCE designs a randomly centralized CH selection mechanism in which every node in the local wireless network is eligible to initiate the centralized CH selection, so that the self-organizing characteristics of mobile ad hoc nodes can be utilized for head selection optimization. Second, taking into account the wireless volatility caused by changes of topology, obstacles, signal strength, etc., the fine-grained cluster relationships maintenance is provided by means of multilevel aliveness and adaptive bidirectional heartbeat packets. Third, RANCE works in an event-driven and on-demand manner instead of a time-triggered manner in LEACH-like protocols, to reduce the impact on continuous services caused by frequent CH handovers among all nodes. Simulation results show that RANCE provides longer clustered time (over 99% of nodes’ lifetime in networks more than 100 nodes) and good clustering scalability with high consistency at minimum energy cost, and exhibits good potentials in mobile wireless environments that are infrastructureless/poor for continuous missions.

Glioblastoma management in a lower middle-income country: Nationwide study of compliance with standard care protocols and survival outcomes in Ukraine.

The effective treatment of high-grade gliomas is a complex problem that requires ubiquitous implementation of sophisticated therapy protocols. The present study aimed to perform population-based analysis of glioblastoma management in lower-middle-income countries. The National Cancer Registry of Ukraine was screened for the records of adult patients with primary glioblastomas diagnosed in 2015-2019. Survival analysis was performed using Kaplan-Meier method and a multivariable Cox model. A total of 2973 adult patients with histologically confirmed glioblastoma were included in the study. Mean age of patients was 55.6 ± 11.4 years, males slightly prevailed-1541 (51.8%) cases. The completed clinical protocol including surgery followed by chemoradiotherapy was applied only in 658 (19.0%) patients. The minority of patients 743 (25.0%) were treated at the academic medical centers, where patients were more likely to receive combined treatment 70.1% compared with 57.9% (P = .0001) at the community hospitals. The overall median survival was 10.6 ± 0.2 months, and the 2-year survival rate was 17%. The number of utilized treatment modalities contributed to better survival rates and was associated with lower hazard ratio: Protocol with 2 modalities - 0.62 (P = .0001), 3 modalities - 0.48 (P = .0001). The management of glioblastoma in lower-middle-income countries is characterized by insufficient availability of treatment in academic medical centers and low rates of advanced therapy application. Survival analysis showed similar prognostic risk factors and outcomes compared with high-income countries.

Nano-gypsum in low dose improves the physicochemical properties of saline-sodic soil

ABSTRACT Increased Na+ ions negatively affect soil physicochemical characteristics. We ran a pot incubation experiment for 2 months and a leaching experiment for another 2 months to monitor the effects of nano-gypsum (NG, <100 nm) in low affordable doses on improving saline-sodic soil physicochemical characteristics. Treatments included a control (CK), conventional gypsum (CG; ≤ 0.5 mm) at 100% CG requirement (8.9 t ha−1: CGR), and three low doses of NG (240, 480 and 960 kg ha−1 = 2.7%, 5.4% and 10.8% of the CGR). Both applications of NG at 10.8% of CGR and the CG at 100% of CGR followed by leaching had the best effect and performed almost equally. However, the use of 960 kg NG ha−1 had the most pronounced effect, where it decreased the bulk density (16.4%) and increased stable soil structure (46.2%). Also, the soil hydraulic conductivity increased by approximately 2.4 times, which helped increase the Na-removal efficiency by 68.9%. Moreover, it decreased soil reaction, electrical conductivity and exchangeable-Na percentage by 15.9%, 39.7% and 71.4% compared to the CK, respectively. Therefore, the NG may introduce novel and alternative application strategy that allows for lower application rate with an adequate gypsum requirement.

Effects of stabilizing materials on soil Cd bioavailability, uptake, transport, and rice growth

Cadmium, a widespread toxic heavy metal in farmland soils, is harmful to human health. A field experiment was conducted to investigate the effects of biochar and biochar-based fertilizers on soil pH, organic matter, and available Cd, as well as rice Cd uptake and translocation. The results showed that rice biomass was significantly increased after both the application of biochar and high rate of biochar-based fertilizers at the tillering stage. The biomass and plant height of rice were improved at filling and maturity stages. Soil pH was significantly increased with the application of biochar but not with the biochar-based fertilizer. The amendments of biochar and biochar-based fertilizers had no significant (p &amp;lt; 0.05) influence on soil organic matter content. The concentration of available Cd in soil and the concentration of Cd in rice were decreased with the application of different amounts of biochar and biochar-based fertilizers in the mature stage. However, this effect was much greater under biochar amendment. Compared to the control, the concentration of available Cd in soil was reduced by 33.09% with the low application rate of biochar, while that was reduced by 18.06% with the high application rate of biochar. The lowest bioaccumulation factor was due to the high concentration of biochar and biochar-based fertilizers. It is concluded that biochar and biochar-based fertilizers particularly at a high addition rate are appropriate for decreasing Cd mobility and improve soil quality for contaminated paddy soils. The study showed a method for the safe production of rice in Cd-polluted farmlands by using a high application rate of biochar or carbon-based fertilizers.

Potential risk to aquatic biota from aerial application of firefighting water additives

The frequency and severity of forest fires is increasing due to climate change. Consequently, there will be an increased use of forest firefighting additives, which increase the ability of water to extinguish fires and prevent reignition. Increased use will potentially result in increased exposure to aquatic ecosystems within forests. This study examined the toxicity of nine firefighting water additives that are currently on the market to three species of freshwater invertebrates that occupy different niches within freshwater ecosystems. The toxicity of the water additives varied up to three orders of magnitude. Pelagic and epibenthic invertebrates are affected at lower rates of application than endobenthic invertebrates. A field relevant application rate of three of the nine water additives tested represent a hazard to freshwater ecosystems under varies exposure scenarios represented by the depth of a theoretical water body (15–200 cm). This study highlights the importance of application buffers around water bodies and the selection of water additives that pose the lowest hazard to freshwater ecosystem, assuming that the efficacy of the additives in extinguishing fires is similar.

Nitrogen and Phosphorus Replacement Value of Three Representative Livestock Manures Applied to Summer Maize in the North China Plain

Land application of livestock manure may reduce the use of mineral fertilizers and alleviate the environmental degradation associated with mineral fertilizers application. However, how to optimize utilization of livestock manure value is not well understood and documentation regarding the nitrogen (N) and phosphorus (P) fertilizer replacement values (NFRV and PFRV, respectively) needs further scrutiny. Therefore, three representative livestock manures, i.e., pig, chicken, and cattle manure, were applied at different usages to assess their N and P availability in comparison to reference mineral fertilizers over summer maize growing seasons. The results show that the average NFRVs of pig, chicken, and cattle manures were 41.7–58.4%, 27.5–44.4%, and −3.6–36.1%, respectively, when based on different references (grain yield, total dry matter yield, grain N uptake, total N uptake), at different N application levels. The NFRV increased with the elevated N application rate for cattle manure treatment. In the P trials, livestock manure had a higher PFRV at a low P application level, and the average PFRVs of pig, chicken, and cattle manures were 80.3–164.8%, 77.9–143.7%, and 94.1–168.0%, respectively, at different P application levels. We conclude that livestock manure produced the lowest NFRV and highest PFRV at a low fertilizer application rate; pig manure had the highest N availability; and cattle manure had the highest P availability.

Efficacy of auxin foliar application on the growth and yield of green Romaine (Lactuca sativa L. var. Jericho) grown under nutrient film technique (NFT) hydroponic system

Green Romaine (Lactuca sativa L. var. Jericho) is one of Malaysia’s trendiest salad greens. It provides many nutrients which vital for human health and body maintenance. This phenomenon has led to an increased in green Romaine production in Malaysia. However, there are several limitations to cultivate this vegetable since conventional planting techniques are still practiced in Malaysia. The present study was undertaken to investigate the efficacy of auxin foliar application on the growth performance and yield of green Romaine grown under the nutrient film technique hydroponic system. The green Romaine was treated with three different application rates of auxin (Indole-3-Acetic Acid); T0, control (0.0 ppm), T1 (50.0 ppm), T2 (100.0 ppm) and T3 (150.0 ppm). The mean value of growth and yield of green Romaine were significantly increased at a lower concentration of auxin application (T1). At this lower application rate, the leaves number of green Romaine significantly increased (P≤0.05) with mean value ranging from 17.0 to 22.0 leaves per plant as compared to the T0, T2 and T3. However, all treated plants do not show any significant increase in term of chlorophyll content. The yields of green Romaine (fresh weight and dry weight) exhibit similar pattern where the auxin foliar application at T1 significantly increased the mean value of the yield parameters with 113.0 – 130.0 g of plant fresh weight while 7.0-10.0 g of plant dry weight as compared to the highest concentration of T3, respectively. This result suggested that a low concentration of auxin helps to increase the growth performance and yield of green Romaine, thus highlights its potential as an effective plant growth promoter for plant grown under hydroponic system.

AN IOT PROTOTYPE TO COLLECT TRANSVERSE VEHICLE POSITION DATA FOR LOCAL ROADS

In New Zealand, most roads are chip-sealed over granular base pavements, which rely on the Transverse Variable Application Spray Bar (TVAS) during the resealing process. TVAS sprays a lower application rate of bitumen in the wheel path areas to limit flushing and uses a higher application rate outside of wheel path areas to limit raveling. Currently, this is carried out by visually identifying the wheel paths where flushing and raveling exist. This manual process is prone to human bias. Ideally, pavement resealing needs to be done before visible signs of distress appear. This study aims to automate obtaining lateral wheel path distribution (LWD) using an Internet of Things (IoT) prototype. This prototype is based on the Arduino platform, which was used to collect wheel placement distributions from vehicles on several sites in Christchurch, New Zealand. Results show that narrow roads exhibit a concentrated wheel path distribution. Additionally, vehicles tend to drive further away from the solid white shoulder line and closer together when parked cars are present. The results can be incorporated into the calibration of the TVAS and pavement design for improved construction and maintenance efficiency.

Using inhibitors to trade greenhouse gas emission for ammonia losses in paddy soil: A zero-sum game

Nitrogen (N) amendment of soil ecosystems alters GHG fluxes to the atmosphere by increasing nitrous oxide (N 2 O) emission and affecting methane (CH 4 ) uptake in well-aerated soils. Although nitrification inhibitors (NIs) can decrease N 2 O emission, this may alter the rate of ammonia (NH 3 ) volatilization, crop yield, and soil CH 4 fluxes by directly or indirectly affecting methane-oxidizing bacteria, causing severe environmental and economic damages. Here, we measured the response of gaseous N loss (N 2 O + NH 3 ) and GHG fluxes (CH 4 + direct N 2 O + indirect N 2 O) to the intensive application of three different rates of DCD (15 to 45 kg ha −1 ) and DMPP (3 to 9 kg ha −1 ) in N fertilized soils imposed upon six different rice cultivars. N addition increased NH 3 volatilization by several orders of magnitude, N 2 O emission by 7- to 10-fold, and CH 4 emission by 2- to 4-fold. DCD and DMPP strongly inhibited the N 2 O emission and, to a lesser extent, CH 4 emission but promoted greater NH 3 losses in a dose-dependent manner. The soil receiving urea with inhibitors exhibited up to 62.7% additional NH 3 volatilization than untreated (inhibitor-free) soils over the rice growth cycle. Considering the estimated indirect N 2 O emission from deposited NH 3 , the overall inhibitory effect of nitrification inhibitors (at different application rates) ranged from 17.4% to 36.6% (reduction) for global warming potential and -6.7% to -45.9% (increase) for nitrogen losses. Collectively, our results suggest moderate inhibition of global warming potential but inadequate reduction of gaseous nitrogen losses by NIs, which were outweighed by increased NH 3 volatilization. Consequently, NIs appear to be a potentially double-edged sword when targeting to diminish gaseous nitrogen losses from N fertilized soils. • N fertilization significantly enhanced the emission of NH 3 , CH 4 and N 2 O. • Higher inhibitory effect of DCD and DMPP for N 2 O than CH 4 fluxes. • DMPP exhibited a similar inhibitory effect to DCD at five-fold low application rates. • NIs appear to be a double-edged sword in diminishing gaseous nitrogen losses.

Scoping review on impact of mosquito - borne diseases of man and animals and use of potential bacterial larvicidal agents to control mosquito vectors

Mosquito vector-borne disease which accounts for the transmission of many deadly diseases like dengue, zika, chikungunya, Rift Valley fever, malaria, West Nile fever, heartworm, lumpy skin disease is one of the major causes of mortality, morbidity, and economic loss to human and animal communities. Though there have been several interventions like insecticide-treated nets, spatial repellents, indoor pesticide sprays to control adult mosquitoes, it only remains effective for short time, possibly leading to faster replacement of the adults by immature only achieving lesser mosquito population reduction. Extensive use of synthetic insecticides leads to resistance, affects non-target organisms and cause ecological imbalance. While recognizing the limitations of the synthetic and adulticide-based mosquito control methods, alternatively, microbial larvicidal agents are more feasible, target-specific, environment-friendly, low application rates, and moderate costs when compared with other vector control measures. This review highlights the microbial larvicidal agents as a most promising tool in vector control management to prevent disease transmission and discusses the major mosquito-borne diseases affecting humans and other animals.

Response of soil organic carbon fractions to legume incorporation into cropping system and the factors affecting it: A global meta-analysis

Recently, there has been increased advocacy for the adoption of rational cropping systems to increase soil organic carbon (SOC) levels and health and ensure food security. The intercropping and crop rotation of legumes with other crops is believed to improve soil environment and influence SOC dynamics. However, a comprehensive assessment of the effects of legume incorporation into cropping systems (LCS) on SOC fractions is still lacking. Therefore, this study aims to elucidate the effects of LCS on SOC fractions under different climatic conditions, soil properties, and agronomic practices, based on meta-analysis of 85 publications. LCS significantly increased the concentrations of microbial biomass carbon (MBC), dissolved organic carbon (DOC), particulate organic carbon, light fraction carbon (LFC), heavy fraction carbon, labile carbon pool, and recalcitrant carbon pool by 21.4 %, 7.2 %, 9.1 %, 29.6 %, 6.4 %, 7.1 %, and 7.9 %, respectively, compared with cropping systems without legume. LCS-induced increase in the contents of SOC fractions was stronger under relatively suitable climatic conditions (mean annual temperature > 15 °C, mean annual precipitation > 1000 mm, and aridity index (AI) > 0.65) and soils with more severe nutrient limitation (soil organic matter < 10 g kg−1, pH < 6.6, and subsoils). Specifically, AI was positively correlated with the response ratios of labile organic carbon fractions, whereas initial soil pH was negatively correlated with MBC, DOC, and LFC. Additionally, low nitrogen fertilizer application rates (< 120 kg ha−1) and intercropping favored an increase in SOC fractions under legume cultivation. Overall, these results provide insights into the ecological benefits of legumes and highlights the importance of developing site-specific strategies to effectively manage SOC dynamics under legume cultivation for sustainable agricultural practices.

Knowledge-Based Treatment Planning Model Improves Organ-at-Risk Sparing and Plan Consistency across Clinics for Prostate Radiation Therapy

<h3>Purpose/Objective(s)</h3> The quality of volumetric modulated arc therapy (VMAT) plans highly depends on the planner's preference and experience. A commercially available knowledge-based planning (KBP) module has been widely implemented to estimate the patient-specific optimal dose-volume histogram and enable semi-automatic treatment planning. The purpose of this study was to investigate whether the KBP clinical implementations have improved organ-at-risk (OAR) sparing and plan quality consistency across clinics within our institution for prostate cancer VMAT treatments. <h3>Materials/Methods</h3> A cohort of 1,484 prostate cancer VMAT treatment plans delivered across three different clinics within our institution from January 2016 to January 2022 were retrospectively identified. The prescription (Rx) schemes of 45 Gy and 70 Gy were selected for statistical investigations since these were the only Rx schemes containing more than 50 VMAT plans created with KBP models. Dosimetric parameters of the bladder, rectum, left/right femoral heads, penile bulb, and volume ratio of 50% isodose line to PTV (R50) were extracted. <h3>Results</h3> Since its first adoption in the last quarter of 2018, KBP planning remained at a low application rate from 0% to 20.0% in each quarter. After publishing KBP models clinically at the beginning of 2021, the application rate of prostate KBP models raised to levels from 53.5% to 71.0% in each quarter. For the 70 Gy Rx scheme, parameters of R50 (w/ KBP: 3.67±4.35 vs w/o KBP: 4.17±6.25, <i>p</i>=0.009), bladder (V_40Gy: 25.49%±13.02% vs 30.50%±16.52%, <i>p</i>=0.002; D_mean: 26.47±9.17 Gy vs 30.51±10.11 Gy, <i>p</i>=0.003) and rectum (V_45Gy: 17.45%±9.25% vs 25.23%±10.40%, <i>p</i><0.001; D_mean: 25.41±5.97 Gy vs 30.59±6.77 Gy, <i>p</i><0.001) were all statistically significantly improved with KBP planning. For the 45 Gy Rx scheme, the results were consistent with the 70 Gy Rx scheme. Across the three different clinics, the investigated parameters became more consistent after the adoption of KBP planning (e.g., bladder D_mean in Gy, w/ KBP: 27.52±10.21, 26.47±9.15 and 31.10±9.83 for clinic 1, 2 and 3, respectively, <i>p</i>₁₂=0.646, <i>p</i>₁₃=0.276, <i>p</i>₂₃=0.453; w/o KBP: 28.03±12.52, 27.02±13.97 and 39.85±23.27 for clinic 1, 2 and 3, respectively, <i>p</i>₁₂=0.425, <i>p</i>₁₃<0.001, <i>p</i>₂₃<0.001). This indicates that, with KBP implementations, we have achieved improved OAR-sparing across the institution as well as increased levels of plan quality standardization. <h3>Conclusion</h3> This study demonstrated that KBP models could improve OAR sparing and plan quality consistency across clinics for prostate VMAT radiation therapy. Clinical adoptions of KBP could potentially reduce inter-planner variations and facilitate the standardization of VMAT treatment planning.

Differential responses of soil nirS- and nirK-type denitrifying microbial communities to long-term application of biogas slurry in a paddy soil

Biogas slurry (BS) has been widely used as an organic fertilizer in rice paddy fields in China, with potential impacts on the diversity and activity of many biogeochemically important microbial communities. Among these communities, denitrifiers play a significant role in nitrogen (N) transformation and loss in such ecosystems. Here, we examined the abundance, diversity, and community composition of nirS- and nirK-type denitrifiers in paddy soils after long-term application of BS with different N contents using quantitative PCR and high-throughput sequencing. The experiment included four treatments: 1) mineral fertilizer with 270 kg N ha−1; 2) BS with 270 kg N ha−1; 3) BS with 405 kg N ha−1; and 4) BS with 540 kg N ha−1. Our results showed that BS application increased the soil nitrite reductase (NIR) activity by 5.9–27.5 % compared to mineral fertilizer application. Higher nirS gene abundance was observed in BS fertilized soils with increasing N content and was significantly correlated with NIR activity, but nirK gene abundance did not change with different fertilization intensities. Biogas slurry as a substitute for mineral fertilizer significantly decreased the alpha-diversity of only nirS-type denitrifiers at low application rate, but such negative effect was offset by increasing BS fertilization intensity. The community compositions of both nirS- and nirK-type denitrifiers shifted following changes in fertilizer type or intensity, and were significantly influenced by soil organic carbon (SOC), available phosphorus (AP), zinc (for both groups), and copper (for only nirK-type denitrifiers). The structural equation model indicated that the differences in soil NIR activity were mainly explained by SOC, AP, Zn, and the nirS-type denitrifier communities. Sulfurifustis, Thiobaclillus, Microvirgula and Duganella appeared to be the main genera governing NIR activity in the studied paddy fields. In conclusion, increasing BS application intensity can greatly alter the abundance and structure of the nirS-type denitrifying communities, and to a lesser extent, those of the nirK-type denitrifiers in paddy soils.

Effects of Chemical Fertilizer Reduction Combined with Straw Application on Diazotrophic Communities in a Double Rice Cropping System

Based on a three-year field experiment, the effects of reduced chemical fertilizer combined with straw application on paddy yield, soil fertility properties, and community structure of diazotrophs in a double-rice cropping field three years after straw application were examined. Three treatments were applied:conventional fertilizer application (CF), chemical fertilizer reduction combined with a low straw application rate (CFLS, 3 t·hm-2), and a high straw application rate (CFHS, 6 t·hm-2). The results showed that CFLS and CFHS did not significantly reduce rice grain yield (P>0.05); significantly neutralized soil acidification; increased soil microbial biomass carbon and nitrogen, dissolved organic carbon, and organic carbon content (P<0.05); and significantly reduced soil redox potential, ammonium nitrogen, and nitrate nitrogen contents (P<0.05). This was more conducive to improve soil nitrogen use efficiency. Compared with those under the CF treatment, the natural nitrogen fixation functional communities of CFLS and CFHS increased the Shannon, PD, and Evenness indexes (P<0.05) due to the improvement of conditions such as the increase in soil carbon storage and the decrease in acidification degree. The relative abundance of microbial communities with nitrogen fixation, carbon fixation, and plant growth promotion functions such as Ferrigenium, Sulfurivermis, Methylomonas, Methylovulum, Ectothiorhodospira, and Nostoc increased significantly (P<0.05). In conclusion, the reduction in chemical fertilizer combined with 3 t·hm-2 and 6 t·hm-2 straw application was an effective measure to improve the community structure of soil diazotrophs and the potential of soil nitrogen fixation.