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The excessive availability of coffee-cherry processing residues has garnered attention, owing to potential environmental concerns associated with ground disposal. The current investigation aims to disclose the characteristics of two main coffee agroindustry residues, i.e., coffee pulp and parchment, as well as the resulting biochar which is produced without chemicals and low energy involved. The effects of washing raw biomass on biochar’s physical–chemical properties were investigated. The pre-washed samples were prepared through the following steps: washing, soaking for 20 h, draining, rinsing, and drying under sunlight for 3 days. A slow pyrolysis process was performed at 420 °C in a pilot-scale apparatus to produce biochar. The results show that the pre-washing of feedstock reduced the ash content in coffee pulp biochar from 28.23 to 11.93%. The ash content of coffee parchment biochar decreased from 9.68 to 5.66% as a result of the washing treatment of the raw material. Furthermore, coffee pulp biochar experienced a 25.8% reduction in surface area, while 14% of the coffee parchment was lost due to washing treatment of raw feedstocks. The findings presented in this study offer new insights that are crucial for evaluating the feasibility and advancing the development of a large-scale commercial process for managing coffee agro-industry residues. [ABSTRACT FROM AUTHOR]

COVID-19 research has relied heavily on convenience-based samples, which—though often necessary—are susceptible to important sampling biases. We begin with a theoretical overview and introduction to the dynamics that underlie sampling bias. We then empirically examine sampling bias in online COVID-19 surveys and evaluate the degree to which common statistical adjustments for demographic covariates successfully attenuate such bias. This registered study analysed responses to identical questions from three convenience and three largely representative samples (total N = 13,731) collected online in Canada within the International COVID-19 Awareness and Responses Evaluation Study (www.icarestudy.com). We compared samples on 11 behavioural and psychological outcomes (e.g., adherence to COVID-19 prevention measures, vaccine intentions) across three time points and employed multiverse-style analyses to examine how 512 combinations of demographic covariates (e.g., sex, age, education, income, ethnicity) impacted sampling discrepancies on these outcomes. Significant discrepancies emerged between samples on 73% of outcomes. Participants in the convenience samples held more positive thoughts towards and engaged in more COVID-19 prevention behaviours. Covariates attenuated sampling differences in only 55% of cases and increased differences in 45%. No covariate performed reliably well. Our results suggest that online convenience samples may display more positive dispositions towards COVID-19 prevention behaviours being studied than would samples drawn using more representative means. Adjusting results for demographic covariates frequently increased rather than decreased bias, suggesting that researchers should be cautious when interpreting adjusted findings. Using multiverse-style analyses as extended sensitivity analyses is recommended. [ABSTRACT FROM AUTHOR]

Introduction and hypothesis: Human menopause transition and post-menopausal syndrome, driven by reduced ovarian activity and estrogen levels, are associated with an increased risk for symptoms including but not limited to sexual dysfunction, metabolic disease, and osteoporosis. Current treatments are limited in efficacy and may have adverse consequences, so investigation for additional treatment options is necessary. Previous studies have demonstrated that percutaneous tibial nerve stimulation (PTNS) and electro-acupuncture near the tibial nerve are minimally invasive treatments that increase vaginal blood perfusion or serum estrogen in the rat model. We hypothesized that PTNS would protect against harmful reproductive and systemic changes associated with menopause. Methods: We examined the effects of twice-weekly PTNS (0.2 ms pulse width, 20 Hz, 2× motor threshold) under ketamine-xylazine anesthesia in ovariectomized (OVX) female Sprague-Dawley rats on menopause-associated physiological parameters including serum estradiol, body weight, blood glucose, bone health, and vaginal blood perfusion. Rats were split into three groups (n = 10 per group): (1) intact control (no stimulation), (2) OVX control (no stimulation), and (3) OVX stimulation (treatment group). Results: PTNS did not affect serum estradiol levels, body weight, or blood glucose. PTNS transiently increased vaginal blood perfusion during stimulation for up to 5 weeks after OVX and increased areal bone mineral density and yield load of the right femur (side of stimulation) compared to the unstimulated OVX control. Conclusions: PTNS may ameliorate some symptoms associated with menopause. Additional studies to elucidate the full potential of PTNS on menopause-associated symptoms under different experimental conditions are warranted. [ABSTRACT FROM AUTHOR]

This study investigated the hydrodeoxygenation (HDO) of oleic acid (OA) that is abundantly found in palm oil for the production of renewable diesel. The effectiveness of mesoporous catalysts, HZSM-5 and zeolite beta, in favoring diesel hydrocarbons was determined. The catalysts were activated by calcination at 550 °C for 5 h and their physicochemical properties were determined using X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature-programmed desorption using ammonia probe molecules (TPD-NH3), and Brunauer–Emmett–Teller analysis (BET). XRD analysis of both zeolite beta and HZSM5 showed high crystalline size of 24 and 84 nm, respectively. BET analysis found that the zeolite beta catalyst had a greater surface area (648 m2 g−1) than HZSM5 (465 m g−1) without significant differences in pore size and volume. According to the TPD-NH3 study, zeolite beta had the most weak + medium acid sites when compared to HZSM5. It should be noted that HZSM5 also demonstrated the presence of strong acid sites. The optimal conditions for both catalysts were 350 °C, 4 MPa hydrogen pressure, and 5% catalyst load over a 2 h reaction period. From the results, the zeolite beta exhibited superior HDO reaction activity than HZSM5 with diesel selectivity ~ 77%. [ABSTRACT FROM AUTHOR]

To address the pressures associated with an increasing energy demand and rising cost of liquid fuel production, alternative feedstocks are being developed. One such potential replacement is bio-oils, which are derived from biomass, however the oil produced is often chemically unstable, corrosive and has low heating values due to the high oxygen content. Thus, an upgrading process is required to lower the oxygen content, with catalytic hydrodeoxygenation being one such technology currently being developed, with mechanistic studies commonly completed utilising model compounds. The current study examines factors that influence catalyst deactivation during hydrodeoxygenation of common bio-oil model compounds over zeolite-supported nickel catalysts, indicating the contribution of functional groups on the formation of condensed-ring products and catalyst deactivation. It was determined that phenolic-hydroxyl groups present in model compounds can facilitate catalyst deactivation through the formation of condensed-ring compounds, identified through decreased cycloalkane yields, causing blockage of catalyst pores. Conversely, when toluene, cyclohexanol and anisole were used as model compound feeds, there were no notable changes in cycloalkane yields, indicating aromatic, alkyl–OH and aromatic–OCH3 have negligible effect on catalyst deactivation. The effect of catalyst metal loading was also examined, and while increased metal content enhanced cyclohexane yields, so to was the formation of condensed-ring products, suggested to be the result of an increased concentration of surface cyclohexane carbocations. Modifications to reaction conditions was studied, with catalyst activity and stability found to improve with increasing reaction temperatures up to 230 °C. Based on the product distributions observed, a coupling reaction pathway (leading to the formation of condensed-ring products and cycloalkanes) is proposed as the hydrodeoxygenation mechanism. [ABSTRACT FROM AUTHOR]

Urodynamic studies, used to understand bladder function, diagnose bladder disease, and develop treatments for dysfunctions, are ideally performed with awake subjects. However, in small and medium-sized animal models, anesthesia is often required for these procedures and can be a research confounder. This study compared the effects of select survival agents (dexmedetomidine, alfaxalone, and propofol) on urodynamic (Δpressure, bladder capacity, bladder compliance, non-voiding contractions, bladder pressure slopes) and anesthetic (change in heart rate [∆HR], average heart rate [HR], reflexes, induction/recovery times) parameters in repeated cystometrograms across five adult male cats. The urodynamic parameters under isoflurane and α-chloralose were also examined in terminal procedures for four cats. Δpressure was greatest with propofol, bladder capacity was highest with α-chloralose, non-voiding contractions were greatest with α-chloralose. Propofol and dexmedetomidine had the highest bladder pressure slopes during the initial and final portions of the cystometrograms respectively. Cats progressed to a deeper plane of anesthesia (lower HR, smaller ΔHR, decreased reflexes) under dexmedetomidine, compared to propofol and alfaxalone. Time to induction was shortest with propofol, and time to recovery was shortest with dexmedetomidine. These agent-specific differences in urodynamic and anesthetic parameters in cats will facilitate appropriate study-specific anesthetic choices. [ABSTRACT FROM AUTHOR]

The primary aim of this research is to study the influence of various experimental parameters on the reaction in order to establish the optimum conditions for which the highest conversion level of zeolite-catalysed oil hydroesterification (two-step reaction: oil hydrolysis and fatty acid esterification) can be achieved. The experimental results indicate that optimising the reaction temperature and stirring rate (providing adequate mass transfer rate and preventing the diffusion limitations) are the main factors to reach into the optimal catalytic performance. An inadequate concentration of water and alcohol can lead to incomplete conversion of the oil during the hydrolysis and fatty acid esterification steps. Exceeding stoichiometric values during hydrolysis (excess H2O) or esterification (excess CH3OH) does not enhance the conversion level of the oil and can act adversely on the extent of hydroesterification. In excess of 95% of the original zeolite activity was recovered via calcination in air during studies of catalyst deactivation. [ABSTRACT FROM AUTHOR]

Introductory environmental studies and sciences (ESS) classes can be powerful and formative experiences for undergraduates. Indeed, instructors likely aspire towards influencing and enhancing the perspectives, analytical tools, and critical-thinking skills their graduates carry forward into careers in and beyond environment-related fields. This task, however, is doubly challenging: not only to meaningfully engage students with environmental issues but ideally also to think critically about the at-times competing ideologies and perspectives in ESS. This requires that courses be taught in ways that further critical thinking, develop metacognitive skills, and introduce students to a diversity of environmental discourses. In this paper, we present the results of a brief empirical survey of a small sample of North American ESS undergraduate programs. Using discussions of climate change as an example, we pay particular attention to the explicit goals, diversity of literature presented, and organization of the courses, using typologies e.g., Nisbet (Wiley Interdiscip Rev Clim Chang 5(6):809-823, ) to highlight the prevalence of particular environmental discourses and not others. We highlight a handful of promising practices and potential blind spots in the pedagogical design of these courses, while arguing for the importance of instructor reflection, iterative improvement, and further research into potential common weaknesses in ESS instruction. [ABSTRACT FROM AUTHOR]

Reaction of phenol with hydrogen peroxide over H-MFI, Fe-MFI, H-BEA, Fe-BEA and TS-1 zeolite catalysts was investigated. Over H-BEA, biphenyl product was observed. It is suggested, that the larger pore size of H-BEA facilitates coupling of two phenol molecules. Two distinct reaction mechanisms are proposed for acid and redox catalysts. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Nodular, cryptocrystalline, weathering-derived magnesite deposits in the New England Orogen, Australia, provide a significant source of high-purity magnesite. Common textural features and related isotopic fingerprints indicate a close genetic relationship between weathering-derived magnesite deposits hosted by ultramafic rocks at Attunga and by sediments at Kunwarara while silica-carbonate rock alteration and rare hydrothermal magnesite vein deposits reflect contrasting conditions of formation. Localised weathering of carbonates in a soil environment shifts stable isotopic composition towards low δC and high δO typical for weathering-derived magnesites while intrusion-related fluids do not significantly change the isotopic composition of affected carbonates. At Attunga, magnesite consists of irregular, nodular veins and masses filling faults and cracks in the weathered serpentinite host rock as well as soft powdery magnesite in pervasive serpentinite alteration zones. The high-grade magnesite at Attunga can be contaminated by amorphous silica and serpentine relicts but does not contain dolomite or ferroan magnesite as observed for its hydrothermal equivalent, the Piedmont magnesite deposit, or other widespread deposits of silica-carbonate rock in the Great Serpentinite Belt. Heavy δO values are compatible with a supergene formation from meteoric waters while low δC suggests C3-photosynthetic plants as the predominant source of carbon for the Attunga magnesites. We infer that weathering-derived, nodular magnesite deposits hosted in ultramafic rocks like the Attunga magnesite deposit have formed in a two-step process involving the hypogene formation of a pre-cursor magnesite deposit and complete supergene overprinting by meteoric waters that acquired carbon from percolation through soil. [ABSTRACT FROM AUTHOR]

This contribution describes the experimental program undertaken to test the performance of a novel firefighting foam against the current Class B foam technology. The novel foam involved the use of a chemical reaction between dissolved species to generate inert nitrogen gas in situ; hence in situ generated nitrogen foams (ISNF). The experimental program encompassed the utilisation of the DEF(AUST)5706 test standard for measuring the suppression and burnback performance of the ISNF as well as that of compressed air foams (CAF). All tests were performed using the same two types of surfactant concentrates (one telomer and one PFOS-based) in order to accurately determine the effect of the generation technology on the foam performance. The three kinds of foams (i.e., aspirated, CAF and ISNF) were characterised in terms of their bubble size distributions and drainage rates. Bubble size analysis placed the size distribution of the ISNF midway between those of aspirated and compressed air foams, whilst drainage performance was found to be only slightly superior to the aspirated foam. The results of the experiments showed that in situ nitrogen foams are able to achieve good performance, similar to that of aspirated and CAF technologies. Further work is needed to optimise foam formulations for ISNF so that surfactants are not affected by the chemistry of nitrogen generation and by the presence of salts formed during chemical reactions. [ABSTRACT FROM AUTHOR]

The experimental program described in this paper sought to assess the suitability of the small scale DEF(AUST)5706 standard for measuring the suppression and burnback performance of Class B foams on pool fires. DEF(AUST)5706 is an Australian Defence standard mandatory for use by the Australian Navy, Army and Air Force. The test protocol required the measurement of the 3/4 control, extinguishment and 1/3 burnback times for a circular pan of aviation gasoline (AVGAS 100/130), 0.28 m in surface area. The test program involved compressed-air foams (CAF) and aspirated foams of two expansion ratios, and employed two AFFF formulations: a 6% telomer concentrate and, to obtain base-line measurements, 3% PFOS FC-600 concentrate which was manufactured by the 3 M company prior to the PFOS phase out. At lower expansion (7:1), the aspirated and compressed-air foams demonstrated similar fire control performance, whilst more expanded (9:1) CAF was generally more efficient at extinguishing, but less efficient in controlling the fire. CAF formed a better seal over the fuel surface and at the hot pan walls, and these foams performed noticeably better than aspirated foam against fuel re-ignition. The paper links these observations with the underlying distributions of bubble sizes, which were measured and fitted to modified Rosin/Rammler cumulative volume distribution functions. We propose that a modified version of DEF(AUST)5706 be adopted as a universal small-scale test protocol. [ABSTRACT FROM AUTHOR]

Letter to the Editor [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editors discuss fire suppression technology.

This short communication presents the findings of the work conducted by the human behaviour in fire permanent working group of the International Association for Fire Safety Science. Its aim is to identify determinants of research gaps in the field of human behaviour in fire. Two workshops were conducted in 2023 in which research gaps were identified and discussed by twenty experts. The workshops led experts through a series of questions to determine the reasons (or determinants) for these gaps in human behaviour in building fires and wildfires. Through the questions, the primary identified determinants were (1) researchers’ literacy in the variety of methods adopted in the field, (2) difficulties associated with recruitment of study participants, (3) multi-disciplinary barriers across different research sub-domains, and (4) issues in obtaining funding for addressing fundamental human behaviour in fire research questions. Two key issues emerged from an open discussion during the workshops, namely the difficulties in attracting and training new people in the field (given the limited educational offers around the world on the topic) and the need for more regular opportunities for the community to meet. [ABSTRACT FROM AUTHOR]