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Dust, algae, mold, lichen, and moss accumulation on the greenhouse cover materials could hinder sun lights and decrease the internal light intensity in greenhouses. Moreover, the traditional way of cleaning greenhouse roofs using ladders is laborious and time-consuming, requires a lot of water, and puts too much pressure on the roof. It could cause damage and risky labor. Consequently, many farmers leave greenhouse roofs dirty, which decreases plant photosynthesis due to the low light intensity. Therefore, this study aimed to design and fabricate a device for cleaning greenhouse roofs. The device parts were a telescopic arm with three concentric and adjustable cylindrical pipes with a rough brush mounted on a frame and connected to a motorized knapsack sprayer. The cleaning part of the 3D model was investigated using Computational Fluid Dynamics (CFD) software. The simulation outcomes informed that the system could supply a uniform nozzle speed. Meanwhile, it could control the water pressure and water flow rate. The analysis of the intensity disorder and the dissipation rate showed positive results for the system and valuable insights for efficient and safe system design. The average transmittances of the greenhouse roof before and after cleaning were 48.7 % and 68.5 %, respectively. Results also showed that the nozzle overlaps increased as the height of the mattress arm increased. There was no interference in all nozzle spray angles, and the first interference was recorded at a nozzle spray angle of 65° and a height of up to 19 cm. The overlap was ranged from 3 cm to 5 cm at a nozzle height of 21.5 cm. The ideal nozzle spacing was 27 cm at a nozzle spray angle of 65°. In conclusion, an efficient greenhouse roof-cleaning device has been developed for small and medium farms. However, further research is needed to enhance its power source, extend its lifespan, and improve its overall efficiency.

Greenhouse technology is crucial for combating climate change and enhancing off-season produce and crop yield. Dust build-up on greenhouse roofs remains a significant problem, significantly reducing light transmission and affecting plant growth. Therefore, this study aims to classify dust build-up on greenhouse roofs and to address it by designing, manufacturing, operating, and evaluating a solar-powered cleaning robot system. Water and cement removal agent (CRA) with different mixing ratios were selected to clean the greenhouse roof. The initial findings demonstrate the greenhouse cover's ability to allow light to pass through can differentiate between different levels of dust accumulation. This study reveals that 88 %–93 % of transmittance levels indicate a clean roof, 82 %–87 % reveal minor dust accumulation, 81 %–75 % denote moderate dust accumulation, and below 75 % signify major dust accumulation. This increased the efficiency of the light intensity for minor dust roofs from 39,285 to 41,731 lux ((CRA) 1:3 water), moderate dust roofs from 36,777 to 39,383 lux ((CRA) 1:1 water), and major dust roofs from 30,585 to 35,525 lux (CRA). The results show a substantial improvement in light transmittance from 88 % to 93 % for clean roofs, compared to much lower levels for dust-accumulated roofs.

This study investigated the potential and sustainable use of the biomass derived from various stages of the grape drying process. A total of eleven byproducts, each containing varying organic materials, were produced and subjected to testing. Ultimate analysis, as well as analyses of heating values, chemical composition, lignocellulose composition, total solids concentration and biogas production were performed with the recommended criteria and assessment methods. The results reveal that carbon (C), nitrogen (N), hydrogen (H), and oxygen (O) levels were significantly different among the byproducts. The ash content of byproducts 5–11 ranged from 3.56 to 5.11%, which was lower than the estimated values in the other byproducts. The analysis of higher heating value showed significantly higher calorific values for byproducts 10 and 11 (22.73 ± 0.08 and 22.80 ± 0.07 MJ kg−1, respectively). Byproducts 1–9 had lower sugar content than byproducts 10 and 11 (rejected raisins). Byproducts 5–9 had the lowest lignin content, and there were no significant differences in neutral detergent fiber (NDF) contents between byproducts 1–6. The highest accumulated biogas volume after 40 days was 11.50 NL L−1 of substrate for byproduct group C (byproducts 10 to 11), followed by 11.20 NL L−1 of substrate for byproduct group B (byproducts 5–9) and 9.51 NL L−1 of substrate for byproduct group A (byproducts 1–4). It is concluded that byproducts consisting of biomass derived at different stages of raisin production may be an effective solid fuel and energy source. The amounts of volatile solids in the tested raisin processing byproducts indicated their appropriateness for pyrolysis conversion to a liquid product with high volatile content.

Until now, wheat has been threshed using stationary thresher machines to meet the farmers' need for a fine straw to feed their livestock, and the farmers require a cutting and binding machine to harvest the wheat crop. Therefore, this paper aims to maximize the utilization of the Japanese rice combine harvester by making modifications to make it suitable for cutting and binding wheat. The modifications involved removing the threshing and cleaning device, replacing it with a binding mechanism, and modifying the feeding and guidance system for vertically transferring the harvested wheat to the binding device. The experiments were executed to assess the modified machine's performance under four different machine's forward speeds (1.65, 2.10, 2.90, and 3.80 km/h), three average weights of the bundle (3, 5, and 7 kg), and three fall heights for wheat bundles (30, 40, and 50 cm). The modified machine was evaluated regarding binding efficiency, number of bundles per hour, total grain losses, field capacity and efficiency, power and energy requirements, and total operating costs. The results revealed that the maximum binding efficiency was 98.80% achieved at 1.65 km/h forward speed, bundle's weight of 3 kg, and bundle's fall height of 30 cm. In addition, under the conditions mentioned earlier, the number of bundles per hour, total grain losses, field capacity and efficiency, power and energy requirements, and total operating costs were 722 bundles/h, 2.83%, 0.189 ha/h, 81.8%, 11.07 kW, 58.57 kW.h/ha, and 2220.40 EGP/ha (∼74.01 USD/ha) respectively.

Reducing reliance on fossil fuels with clean and sustainable alternatives is essential for mitigating climate change and global warming-related environmental concerns. Previous researchers have studied the performance of choppers and crushers as separate units powered by diesel or gasoline engines. Nowadays, an increasing interest in producing Eco-friendly machines that stand out for being dual purposes, cost-effectiveness, and with lengths suitable for feeding ruminants are imperative to achieving economic and sustainable goals. Therefore, this study aims to solve these issues and gaps by developing and evaluating a dual-purpose forage machine for chopping and crushing operations to achieve both operations more efficiently and at a lower cost. The developed forage machine's performance was evaluated for chopping operation using maize stalks with four different rotational speeds of 1200, 1400, 1600, and 1800 rpm and four different moisture contents of 22.7, 43.3, 59.8, and 74.6% (w.b.). Also, the crushing operation was evaluated using maize ears with four different crusher speeds of 1200, 1400, 1600, and 1800 rpm and three different sieves with holes' diameters of 6, 8, and 10 mm. The results concluded that the highest efficiencies with values of 94.17 and 92.85% were obtained at 1800 rpm chopper rotational speed and 22.7% moisture content for the chopper and 1200 rpm crusher rotational speed and 10 mm sieve hole diameter for the crusher, respectively. At these proper operational parameters, the machine productivity of 2.44 and 0.31 ton.hr−1, the specific energy requirements of 3.22 and 4.50 kW h.ton−1, and the estimated production costs of 23.56 and 121.24 EGP.ton−1 (1.25 and 6.38 USD.ton−1) were obtained for chopper and crusher, respectively.

Due to the recent high prices of livestock feed in the world and the new sustainable management practices of rice straw, livestock farmers are obligated to either use or purchase rice straw and cut it to desired lengths to feed ruminants. Therefore, this study aimed to construct a combined machine for collecting and chopping rice straw for lengths preferred in feeding ruminants. The combined machine comprises three main units: a picking up unit, a chopping unit, and a takeout unit. Field experiments were performed on average rice straw moisture content of 25% (w.b.) to evaluate the performance of the combined machine, under factors of 1.3, 1.6, 1.9, and 2.2 km h−1 forward speeds, elevator velocities of 0.79, 0.94, and 1.10 m s−1, and chopping knives rotational speeds of 1600, 2000 and 2400 rpm. The obtained results indicated that the consumed specific energy was 90.94 kWh ha−1 to achieve the highest field capacity of 0.24 ha h−1, with collecting efficiency of 95.30% at a forward speed of 2.2 km h−1, elevator velocity of 1.10 m s−1 and rotational speed of 2400 rpm for chopping knives. In order to achieve the highest chopping quality of 95%, it is recommended to operate the elevator velocity at 0.79 m s−1, rotate chopping knives at 2400 rpm, and drive the tractor at a forward speed of 1.3 km h−1. The total operating cost of the combined machine is lower than the traditional methods by about 49.84%.

This study aimed to evaluate the ability of the response surface methodology (RSM) approach to predict the tractive performance of an agricultural tractor during semi-deep tillage operations. The studied parameters of tractor performance, including slippage (S), drawbar power (DP) and traction efficiency (TE), were affected by two different types of tillage tool (paraplow and subsoiler), three different levels of operating depth (30, 40 and 50 cm), and four different levels of forward speed (1.8, 2.3, 2.9 and 3.5 km h−1). Tractors drove a vertical load at two levels (225 kg and no weight) in four replications, forming a total of 192 datapoints. Field test results showed that all variables except vertical load, and different combinations of this and other variables, were effective for the S, DP and TE. Increments in speed and depth resulted in an increase and decrease in S and TE, respectively. Additionally, the RSM approach displayed changes in slippage, drawbar power and traction efficiency, resulting from alterations in tine type, depth, speed and vertical load at 3D views, with high accuracy due to the graph’s surfaces, with many small pixels. The RSM model predicted the slippage as 6.75%, drawbar power as 2.23 kW and traction efficiency as 82.91% at the optimal state for the paraplow tine, with an operating depth of 30 cm, forward speed of 2.07 km h−1 and a vertical load of 0.01 kg.

The incidence of culture-negative NVO (CN-NVO) cases is increasing, presenting significant diagnostic and therapeutic challenges due to the inability to isolate causative organisms with conventional microbiological methods. Factors influencing the diagnosis of CN-NVO include prior antimicrobial therapy, low pathogen burden, fastidious or intracellular organisms, technical issues, and non-infectious mimickers. Diagnosis often relies on imaging modalities like magnetic resonance imaging (MRI) and computed tomography (CT)-guided biopsy, though these methods can sometimes fail to yield positive microbiological results. Advanced diagnostic tools, such as polymerase chain reaction (PCR), metagenomic next-generation sequencing (mNGS), and cell-free DNA analysis, may be necessary to identify the pathogen. The causative pathogen cannot be isolated in some patients, among which an empirical antimicrobial therapy should be initiated. This narrative review discusses the management, monitoring, surgical indications, and outcomes for patients with CN-NVO.

Background: Recent advances in shotgun metagenomic sequencing (sMGS) for detecting microbial cell-free DNA (mcfDNA) in peripheral blood have shown promise across various patient populations. This study evaluates the application of sMGS for diagnosing osteoarticular infections (OAIs), a condition with significant diagnostic challenges., Methods: We conducted a retrospective analysis on 73 patients suspected of OAIs at the Mayo Clinic from 2019 to 2023, incorporating mcfDNA sMGS (Karius test [KT]) into their diagnostic evaluation. We categorized the clinical impact of KT on OAI diagnoses and management into 4 distinct outcomes. (1) KT was able to confirm an established diagnosis, (2) KT supported noninfectious diseases diagnosis, (3) KT established an unsuspected diagnosis, (4) KT did not add relevant information., Results: In our cohort, KT was performed in 73 patients. Among the infected individuals, KT yielded positive results in 22 of 43 (51.2%) cases. Of these 22 cases, 11 (50%) showed agreement with conventional diagnostic workup, whereas in 5 (22.7%) cases, the KT established an unsuspected diagnosis. Native vertebral osteomyelitis diagnosis ( P < .001) or OAIs with concomitant presence of endocarditis or endovascular infection ( P = .005) were statistically associated with a definite, probable, or possible diagnostic certainty of KT result., Conclusions: In complex OAIs, KT enhanced diagnostic accuracy by 11.6%, proving especially beneficial in diagnosing native vertebral osteomyelitis and infections with concurrent endocarditis or endovascular complications. Our findings underscore the utility of KT in the diagnostic workflow for challenging OAI cases, potentially altering clinical management for a significant subset of patients., Competing Interests: Potential conflicts of interest. All authors declare no competing interests., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)