Search Results (69)

Lignocellulosic waste materials are among the most abundant raw materials on Earth, and they have been widely studied as natural additives in materials, especially for polymer composites, with interesting results when it comes to improving physiochemical properties. The main components of these materials are cellulose, hemicellulose, and lignin, as well as small amounts of other polysaccharides, proteins, and other extractives. Several kinds of lignocellulosic materials, mainly fibers, have been evaluated in polymer matrices, and recently, the use of particles has increased due to their high surface area. Garlic is a spice seed that generates a waste husk that does not have applications, and there are no reports of industrial use of this kind of lignocellulosic material. Additive manufacturing, also known as 3D printing, is a polymer processing technique that allows for obtaining complex shapes that are hard to obtain with ordinary techniques. The use of composites based on synthetic polymers and lignocellulosic materials is a growing field of research. In the present work, the elaboration and evaluation of 3D-printed polypropylene–garlic husk particle (PP-GHP) composites are reported. First, the process of obtaining a filament by means of a single extrusion was carried out, using different GHP contents in the composites. Once the filament was obtained, it was taken to a 3D printer to obtain probes that were characterized using differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) was performed with the aim of evaluating the thermal behavior of the 3D-printed PP-GHP composites. According to the obtained results, the crystallization process and thermal stability of the PP-GHP composites were modified with the presence of GHP compared with pristine PP. Dynamic mechanical analysis (DMA) showed that the addition of GHP decreased the storage modulus of the printed composites and that the Tan δ peak width increased, which was associated with an increase in toughness and a more complex structure of the 3D-printed composites. X-ray diffraction (XRD) showed that the addition of GHP favored the presence of the β-phase of PP in the printed composites. Full article

Ground heat pump systems (GHPSs) are esteemed for their high efficiency within renewable energy technologies, providing effective solutions for heating and cooling requirements. These GHPSs operate by utilizing the relatively constant temperature of the Earth’s subsurface as a thermal source or sink. This feature allows them to perform greater energy transfer than traditional heating and cooling systems (i.e., heating, ventilation, and air conditioning (HVAC)). The GHPSs represent a sustainable and cost-effective temperature-regulating solution in diverse applications. The ground heat exchanger (GHE) technology is well known, with extensive research and development conducted in recent decades significantly advancing its applications. Improving GHE performance factors is vital for enhancing heat transfer efficiency and overall GHPS performance. Therefore, this paper provides a comprehensive review of research on various factors affecting GHE performance, such as soil thermal properties, backfill material properties, borehole depth, spacing, U-tube pipe properties, and heat carrier fluid type and velocity. It also discusses their impact on heat transfer efficiency and proposes optimal solutions for improving GHE performance. Full article

Poultry carcasses may be reservoirs for the zoonotic transmission of antimicrobial-resistant bacteria to humans and pose a major public health hazard. During the isolation of Salmonella from poultry and other foods, many of the presumptive typical Salmonella colonies on xylose lysine deoxycholate (XLD) agar were found to lack the invA gene, which is the specific target gene for Salmonella spp. Therefore, the current study aimed to estimate the prevalence and antimicrobial resistance profiles of extensively drug-resistant invA-negative non-Salmonella isolates recovered from native Egyptian chicken carcasses as presumptive Salmonella colonies on XLD agar. The non-Salmonella isolates were detected in 84% (126/150) of the examined native Egyptian chicken carcasses and classified into five genera, with prevalence rates of 64% (96/150), 14% (21/150), 6.7% (10/150), 3.3% (5/150), and 1.3% (2/150) for Proteus, Citrobacter, Shigella, Pseudomonas, and Edwardsiella, respectively. One hundred and ninety-five invA-negative, non-verified presumptive Salmonella isolates were recovered and classified at the species level into Proteus mirabilis (132/195; 67.7%), Proteus vulgaris (11/195; 5.6%), Citrobacter freundii (26/195; 13.3%), Shigella flexneri (8/195; 4.1%), Shigella sonnei (6/195; 3.1%), Shigella dysenteriae (3/195; 1.5%), Pseudomonas fluorescens (6/195; 3.1%), and Edwardsiella tarda (3/195; 1.5%). All (195/195; 100%) of these isolates showed resistance against cefaclor and fosfomycin. Additionally, these isolates showed high resistance rates of 98%, 92.8%, 89.7%, 89.2%, 89.2%, 86.7%, 80%, 78.5%, 74.4%, and 73.9% against cephalothin, azithromycin, vancomycin, nalidixic acid, tetracycline, sulfamethoxazole/trimethoprim, cefepime, gentamicin, cefotaxime, and ciprofloxacin, respectively. Interestingly, all (195/195; 100%) of the identified isolates were resistant to at least five antibiotics and exhibited an average MAR (multiple antibiotic resistance) index of 0.783. Furthermore, 73.9% of the examined isolates were classified as extensively drug-resistant, with an MAR index equal to 0.830. The high prevalence of extensively drug-resistant foodborne Proteus, Citrobacter, Shigella, Pseudomonas, and Edwardsiella isolated from native chicken carcasses poses a great hazard to public health and necessitates more monitoring and concern about the overuse and misuse of antibiotics in humans and animals. This study also recommends the strict implementation of GHP (good hygienic practices) and GMP (good manufacturing practices) in the chicken meat supply chain to protect consumer health. Full article

A reference material (RM), as defined by the International Vocabulary of Metrology (VIM 2012), must be homogeneous, stable, and suitable for use in measurements. Certified reference materials (CRMs) are RMs with documented property values, uncertainties, and traceability. ISO 17034:2018 outlines the requirements for RM producers, ensuring that CRMs meet standards for stability, uniformity, and reproducibility. In Europe, CE marking, from French “conformité Européenne”, which means European conformity, has been mandatory for thermal insulation products since 2002, ensuring their thermal performance is verified by accredited laboratories using RMs like IRMM440 and ERM FC440. Annually, European manufacturers produce over 200 million cubic meters of thermal insulation, necessitating thousands of thermal conductivity measurements daily to maintain CE marking compliance. Key characteristics of Reference Materials include long-term stability, thermal conductivity within specified ranges, and minimal dependence on density, thickness, and applied load. Sample thickness must conform to apparatus specifications, and homogeneity must be quantified. Reference Materials must also have appropriate dimensions, surface smoothness, and manufacturability. The Joint Research Centre (JRC) Geel has produced two Reference Materials, IRMM 440 and ERM FC 440, with specific characteristics to meet these requirements. Both are glass wool fibers with low thermal conductivity and specific density and thickness. The qualification of RMs involves inter-laboratory comparisons to ensure the accuracy and traceability of thermal conductivity measurements. The European market’s organization, including the use of Reference Materials and CE marking, has significantly improved measurement consistency and product quality. This system has led to lower uncertainties in thermal conductivity measurements compared to North America, highlighting the impact of standardized RMs on industry practices. Future needs include developing RMs with lower conductivity and increased thickness to accommodate market trends towards super insulation materials and bio-based components, enhancing energy performance calculations for buildings. This paper will present the process of defining a reference material and how it affects the uncertainty level of the calculation of building energy performance. This level depends on the characteristics of the materials used, their implementation, and external factors, such as the weather, as well as the reference material used for calibration of all European thermal conductivity measurement devices. Full article

Accurately quantifying flora and their respective anatomical structures within natural ecosystems is paramount for both botanical breeders and agricultural cultivators. For breeders, precise plant enumeration during the flowering phase is instrumental in discriminating genotypes exhibiting heightened flowering frequencies, while for growers, such data inform potential crop rotation strategies. Moreover, the quantification of specific plant components, such as flowers, can offer prognostic insights into the potential yield variances among different genotypes, thereby facilitating informed decisions pertaining to production levels. The overarching aim of the present investigation is to explore the capabilities of a neural network termed GhP2-YOLO, predicated on advanced deep learning techniques and multi-target tracking algorithms, specifically tailored for the enumeration of rapeseed flower buds and blossoms from recorded video frames. Building upon the foundation of the renowned object detection model YOLO v8, this network integrates a specialized P2 detection head and the Ghost module to augment the model’s capacity for detecting diminutive targets with lower resolutions. This modification not only renders the model more adept at target identification but also renders it more lightweight and less computationally intensive. The optimal iteration of GhP2-YOLOm demonstrated exceptional accuracy in quantifying rapeseed flower samples, showcasing an impressive mean average precision at 50% intersection over union metric surpassing 95%. Leveraging the virtues of StrongSORT, the subsequent tracking of rapeseed flower buds and blossom patterns within the video dataset was adeptly realized. By selecting 20 video segments for comparative analysis between manual and automated counts of rapeseed flowers, buds, and the overall target count, a robust correlation was evidenced, with R-squared coefficients measuring 0.9719, 0.986, and 0.9753, respectively. Conclusively, a user-friendly “Rapeseed flower detection” system was developed utilizing a GUI and PyQt5 interface, facilitating the visualization of rapeseed flowers and buds. This system holds promising utility in field surveillance apparatus, enabling agriculturalists to monitor the developmental progress of rapeseed flowers in real time. This innovative study introduces automated tracking and tallying methodologies within video footage, positioning deep convolutional neural networks and multi-target tracking protocols as invaluable assets in the realms of botanical research and agricultural administration. Full article

The main aim of this study was to analyze hygiene practices in small-scale dairy plants (SSDPs) in Serbia. A total of 60 plants were included in the research. A survey questionnaire used for SSDPs was designed to obtain the main information about hygiene practices they perform, as well as the data about the SSDPs, their production portfolio, and improvement plans. For the purpose of this study, a good hygiene practice score (GHPS) was calculated showing that the average score is 75%, spanning from 71.4% to 80.3% depending on the type of dairy plant. This study showed that the biggest challenges for small-scale dairy plants are associated with adequate labeling and external analysis of their dairy products, followed by record keeping and use of appropriate food contact materials. As expected, registered and approved SSDPs had higher GHPS scores and more information on their labels than those still in the approval or registration process. This study confirms the need for supporting this type of dairy producer to improve two main pillars of their business—the infrastructure for where they produce dairy products and awareness/knowledge of food safety legislative requirements. At the same time, approved processors are significantly underutilizing their processing capacity, which implies the need for both policy change consideration and educational initiatives. The policy changes should aim to align regulations with small-scale dairy processing realities. Full article

Natural and bio-based construction materials such as bamboo, cork, or natural fiber composites offer a promising solution for enhancing the environmental sustainability of buildings. In this sense, the paper presents an experimental thermo-acoustic characterization of four common Ecuadorian natural fibers, abaca (Musa textilis), cabuya (Furcraea andina), coir (Cocos nucifera), and totora (Schoenoplectus californicus). Different densities were considered, from 85 kg/m³ (Cabuya) to 244 kg/m³ (totora), to thermo-acoustically characterize the samples built with these fibers, by means of the guarded-hot-plate (GHP) and impedance tube methods in-lab experimental benches. The exhaustive original characterization of the evaluated natural fiber composites showed a promising overall thermo-acoustic behavior. The thermal conductivity of the fibers was around 0.04–0.06 W/m·K and, therefore, comparable to other materials such as polystyrene, polyurethane, or aerogel that are already utilized for similar applications. On the other hand, the sound-absorption properties of the evaluated fibers are also very competitive, but strongly affected by the thickness of the sample, with noise reduction coefficient NRC ranging from 0.12 to 0.53. Consequently, the production and distribution of these materials in the Ecuadorian market for thermal insulation and acoustic conditioning constitute an alternative characterized by good technical performance, which, compared to synthetic composites used in the construction industry for similar duties, is ecological, sustainable, and has low built-in energy consumption. Full article

The present study investigates the interactions between eight glucosinolate hydrolysis products (GHPs) sourced from broccoli by-products and the detoxifying enzymes of Botrytis cinerea, namely eburicol 14-alpha-demethylase (CYP51) and glutathione-S-transferase (GST), through in silico analysis. Additionally, in vitro assays were conducted to explore the impact of these compounds on fungal growth. Our findings reveal that GHPs exhibit greater efficacy in inhibiting conidia germination compared to mycelium growth. Furthermore, the results demonstrate the antifungal activity of glucosinolate hydrolysis products derived from various parts of the broccoli plant, including inflorescences, leaves, and stems, against B. cinerea. Importantly, the results suggest that these hydrolysis products interact with the detoxifying enzymes of the fungus, potentially contributing to their antifungal properties. Extracts rich in GHPs, particularly iberin and indole-GHPs, derived from broccoli by-products emerge as promising candidates for biofungicidal applications, offering a sustainable and novel approach to plant protection by harnessing bioactive compounds from agricultural residues. Full article

The escalating energy demands in buildings, particularly for heating and cooling demands met by heat pumps, have placed a growing stress on energy resources. The bi-functional thermal diode tank (BTDT) is proposed as thermal energy storage to improve the heating and cooling performances of heat pumps in both summer and winter. The BTDT is an insulated water tank with a gravity heat pipe (GHP), which can harvest and store heat passively from sun radiation and the external environment during the daytime. In summer, it harvests and stores cold energy from the air and night sky during the daytime. The performance of the BTDT-assisted heat pump (BTDT-HP) system in Adelaide, Australia, during the 2021–2022 summer and winter seasons was evaluated by conducting a TRNSYS simulation. This study revealed that the BTDT-HP system outperformed the reference ASHP system, where up to 8% energy in heating and 39.75% energy in cooling could be saved. An overall reduction in the energy consumption of 18.89% was achieved. Increasing the BTDT volume and GHP panel area enabled the tank to store more thermal and cold energy across the winter and summer seasons, thereby improving the system’s performance. The maximum ESPs were found to be 31.6% and 41.2% for heating and cooling for the study case under optimal conditions. When the GHP panel area was fixed at 15 m², the BTDT volume should be at least 28 m³ for the BTDT-HP system, boasting cooling and heating capacities of 40 kW and 43.2 kW, to achieve positive energy savings. Full article

The objective was to evaluate the effects of good handling practices on dairy calf welfare. Forty-eight crossbred dairy calves were assigned to two treatments: conventional handling (CH): calves kept in individual pens, fed milk replacer in buckets without nipples and abruptly weaned; or good handling practices (GHP): calves kept in group pens, fed milk replacer in buckets with nipples, given daily tactile stimulation during feeding, and progressive weaning. Calf welfare was assessed from birth to 120 days of age, based on: health (plasma concentrations of glucose and IgG, and occurrences of diarrhea, pneumonia, tick-borne disease, or death); physiology (heart rate [HR], respiratory rate [RR], and rectal temperature [RT]); behavior (flight distance [FD], latencies for first movement [LM] and to hold the calf in a pen corner [LH], and total time a calf allowed touching [TTT]); and performance indicators (body weight, average daily gain, and weaning success at 70 days of age). Calves in the GHP treatment had a lower HR at 30 days of age, shorter FD and LH, longer TTT, and lower RR and RT than CH (p < 0.05). However, health, deaths and performance indicators did not differ (p > 0.05) between treatments. Based on various indicators, GHP improved dairy calf welfare. Full article

Monitoring the temperature of the coal gangue mountains is fundamental to preventing their spontaneous combustion. However, the existing temperature monitoring systems fail to achieve stable, pollution-free temperature monitoring without affecting vegetation growth in these mountains. To address this issue, this work proposes a flexible thermoelectric device (FTD) based on a protrusion-structured liquid metal elastomer (LME). Utilizing a high-thermal-conductivity LME, the FTD adheres closely to the surface of the gravity heat pipe (GHP), ensuring compatibility between FTD and the curved surface of the GHP. Simultaneously, employing a low-thermal-conductivity elastomer helps concentrate heat onto FTD, thereby enhancing thermoelectric power generation efficiency. Additionally, the impact of the shape, size, and height of the protrusion structure at the cold end of the GHP on its efficiency was also investigated. The practical application of FTD on GHP was demonstrated. Full article

Background: We recently developed a gene-expression-based HOT score to identify the hot/cold phenotype of head and neck squamous cell carcinomas (HNSCCs), which is associated with the response to immunotherapy. Our goal was to determine whether radiomic profiling from computed tomography (CT) scans can distinguish hot and cold HNSCC. Method: We included 113 patients from The Cancer Genome Atlas (TCGA) and 20 patients from the Groupe Hospitalier Pitié-Salpêtrière (GHPS) with HNSCC, all with available pre-treatment CT scans. The hot/cold phenotype was computed for all patients using the HOT score. The IBEX software (version 4.11.9, accessed on 30 march 2020) was used to extract radiomic features from the delineated tumor region in both datasets, and the intraclass correlation coefficient (ICC) was computed to select robust features. Machine learning classifier models were trained and tested in the TCGA dataset and validated using the area under the receiver operator characteristic curve (AUC) in the GHPS cohort. Results: A total of 144 radiomic features with an ICC >0.9 was selected. An XGBoost model including these selected features showed the best performance prediction of the hot/cold phenotype with AUC = 0.86 in the GHPS validation dataset. Conclusions and Relevance: We identified a relevant radiomic model to capture the overall hot/cold phenotype of HNSCC. This non-invasive approach could help with the identification of patients with HNSCC who may benefit from immunotherapy. Full article

Bacillus cereus (hereafter, B. cereus) poisoning often arises from the consumption of Ready-To-Reheat vegetable soups in which an intensive growth of the vegetative cells of B. cereus take place. The market for these soups is increasing significantly worldwide. For the producer it is important to determine if soups can promote the growth of B. cereus, by calculating its growth potential. We can achieve this goal by carrying out an efficient challenge test. In our study we have designed and performed a challenge test in three batches of an emmer (Triticum monococcum) and vegetable soup that undergo a second pasteurization treatment after packaging. We found out that under refrigeration conditions B. cereus is unable to multiply in the soup, instead, under conditions of thermal abuse, B. cereus can grow during 90 days of shelf life with a growth potential of 0.82 logarithms. It is essential to keep the entire production phase under control using effective GMP (Good Manufacturing Practices) and GHP (Good Hygiene Practices) measures, to ensure that the freshly produced soups contain low loads of the spores of B. cereus. In this way, the vegetative cells born from the germination of the spores cannot reach the infectious dose necessary to induce the food poisoning. Full article

Vertical borehole geothermal heat pumps (GHPs) offer eco-friendly and energy-efficient heating and cooling. This paper proposes enhancing the coefficient of performance (COP) by converting air source heat pumps (ASHPs) into ground source heat pumps (GSHPs). This study presents a cost-effective approach to utilizing existing water boreholes in Pakistani buildings, reducing drilling and piping expenses. The results show that GSHPs achieved average COP values of 5.92, 33.33% higher than ASHPs. GSHPs demonstrated an average energy efficiency ratio (EER) of 20.12, exceeding ASHPs by 33.9%. These findings highlight the enhanced COP and energy efficiency of GSHPs, making them an attractive option for sustainable HVAC systems. Full article

Globally, a green hydrogen economy rush is underway, and many companies, investors, governments, and environmentalists consider it as an energy source that could foster the global energy transition. The enormous potential for hydrogen production, for domestic use and export, places Africa in the spotlight in the green hydrogen economy discourse. This discourse remains unsettled regarding how natural resources, such as land and water, can be sustainably utilized for such a resource-intensive project, and what implications this would have. This review argues that green hydrogen production (GHP) in Africa has consequences where land resources (and their associated natural resources) are concerned. It discusses the current trends in GHP in Africa, and the possibilities for reducing any potential pressures it may put on land and other resource use on the continent. The approach of the review is interpretive, and hinges on answering three questions, concerning the what, why, and how of GHP and its land consequences in Africa. The review is based on 41 studies identified from Google Scholar, and sources identified via snowballed recommendations from experts. The GHP implications identified relate to land and water use, mining-related land stress, and environmental, ecological, and land-related socioeconomic consequences. The paper concludes that GHP may not foster the global energy transition, as is being opined by many renewable energy enthusiasts but, rather, could help foster this transition as part of a greener energy mix. It notes that African countries that have the potential for GHP require the institutionalization of, or a change in, their existing approaches to land-related energy governance systems, in order to achieve success. Full article