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This study investigated the non-isothermal (5, 10, and 20 °C/min) pyrolysis of non-metallic fractions (NMFs) of the FR-2 (phenolic resin reinforced with laminated paper) and FR-4 (epoxy resin reinforced with glass fiber) type waste printed circuit boards (WPCBs), under an inert atmosphere of flowing nitrogen gas. Three iso-conversional kinetic models (Friedman, Flyn-Wall–Ozawa (FWO), and Kissinger–Akahira–Sunose (KAS) approaches) were employed to understand the kinetics of the pyrolysis process. Thermogravimetric-differential thermogravimetric (TG-DTG) analysis revealed that FR-4 NMFs displayed a shift in mass loss above 287 °C at a heating rate of 10 °C/min and reached 95% conversion at 515 °C. In the case of the FR-2 NMFs, two distinct devolatilization zones were observed between 250–330 °C and 330–530 °C. The kinetic investigation revealed mean activation energy values of 264.38 kJ/mol for FR-2 and 221.99 kJ/mol for FR-4. The pyrolysis reaction mechanism for FR-2 NMFs displayed a decreasing trend for conversion (α), which was indicative of the simplified third-order model (F3) until α = 0.5 and shifted to second-order diffusion (D2) in the later part of the conversion. For FR-4 NMFs, the reaction function f(α) is between random nucleation with three nuclei on the individual particle (F3) and random nucleation with one nucleus on the individual particle (F1) over the selected range of conversion. For the FR-2 and FR-4 NMFs, the average ΔH values were 259.30 and 217.00 kJ/mol, and ΔG values were 161.03 and 176.92 kJ/mol, respectively.

Phosphorus (P) is an essential macronutrient for plants. The focus of this work is to recover P from biosolids and their derived biochar. The effect of three different pyrolysis temperatures (400 °C, 500 °C, and 600 °C) and two carrier gases (CO2 and N2) on P fractionation and the speciation of P on biochars produced from two biosolids were investigated. The Hedley chemical sequential extraction method and 31P liquid NMR were used for P characterization and quantification. Higher pyrolysis temperatures increased P fixation and decreased short-term P bioavailability. Carrier gas had also significant effects on P fractionation in the biochars. Biochar produced in a CO2 environment had slightly higher water-soluble P, NaHCO3-Pi, NaOH-Pi, and residual P than in biochar prepared in a N2 environment, while HCl-P showed the opposite trend. Additionally, the predominant molecular configuration of P was present in the inorganic form identified by 31P liquid NMR spectra, while organic P transformed into inorganic P with increasing pyrolysis temperature.

Slow pyrolysis was carried out in biosolids under three different temperatures (400, 500 and 600 °C) and two different carrier gases (CO2 and N2) on a fluidized bed reactor. The total concentration, chemical fractionation, and plant availability of the heavy metals in biochar were assessed by standard methods. The total concentration of Fe, Zn, Cu, Mn, Cr, Ni and Pb increased with the conversion of biosolids to biochar and with increasing pyrolysis temperature. The community’s Bureau of Reference (BCR) sequential extraction identified the migration of metals from toxic and bioavailable to potentially stable available or non-available forms at higher pyrolysis temperatures. Diethylenetriamine penta-acetic acid (DTPA)-extractable metals (Cu, Zn, Cd, Cu, Fe and Pb) were significantly lower in biochar compared to biosolids. By replacing N2 with CO2, the total metal concentration of heavy metals was significantly different for Mn, Ni, Cd, Pb and As. There were larger amounts of metals in the residual and oxidizable fractions compared to when N2 was used as a carrier gas. Consequently, the biochar produced at higher temperatures (500 and 600 °C) in the N2 environment exhibited lower potential ecological risks than in CO2 environments (69.94 and 52.16, respectively, compared to values from 75.95 to 151.38 for biochars prepared in N2). Overall, the results suggest that the higher temperature biochar can support obtaining environmentally safe biochar and can be effective in attenuating the ecological risks of biosolids.

Per- and polyfluoroalkyl substances (PFAS) are a group of fluorinated synthetic chemicals that are highly recalcitrant, toxic, and bio-accumulative and have been detected in biosolids worldwide, posing potential risks to humans and the environment. Recent studies suggest that the organic C-F bond in PFAS can be destructed and potentially mineralised into inorganic fluorides during thermal treatment. This study focuses on thermodynamic equilibrium investigations and the fate of fluorine compounds post-PFAS destruction during biosolid thermal treatment. The results indicate that gas-phase fluorine compounds are mainly hydrogen fluoride (HF) and alkali fluorides, whereas solid-phase fluorine compounds include alkaline earth fluorides and their spinels. High moisture and oxygen content in the volatiles increased the concentration of HF in the gas phase. However, adding minerals reduced the emission of HF in the gas phase significantly and enhanced the capture of fluorine as CaF2 spinel in the solid phase. This study also investigates the effect of feedstock composition on the fate of fluorine. High ash content and low volatile matter in the feedstock reduced HF gas emissions and increased fluorine capture in the solid product. The findings of this work are useful in designing thermal systems with optimised operating conditions for minimising the release of fluorinated species during the thermal treatment of PFAS-containing biosolids.

The process of breaking down chicken manure through anaerobic digestion is an effective waste management technology. However, chicken manure can be a challenging feedstock, causing ammonia stress and digester instability. This study examined the impacts of adding wood biochar and acid-alkali-treated wood biochar to anaerobically digest chicken manure under conditions of ammonia inhibition. The results highlighted that only the addition of 5 % acid-alkali-treated wood biochar by volume can achieve cumulative methane production close to the typical methane potential range of chicken manure. The treated wood biochar also exhibited highest total ammonia nitrogen removal compared to the Control treatment. Scanning Electron Microscope revealed growing interactions between biochar and methanogens over time. Real-time polymerase chain reaction showed that treated wood biochar produced the highest number of bacterial biomass. In addition, 16S amplicon-based sequencing identified a more robust archaeal community from treated biochar addition. Overall, the acid-alkali treatment of biochar represents an effective method of modifying biochar to improve its performance in anaerobic digestion.

This study aimed to investigate the impact of biosolids-derived biochar on the remediation of Australian soil contaminated with diesel while investigating the role of biochar in the remediation. To achieve the latter aim, sodium azide (NaN3) was added to a separate biochar treatment (BN) to alter the bacterial community structure. Biochar (B) reduced detectable hydrocarbons by 2353 mg/kg compared to the control (C) treatment at week 24. However, the BN treatment reduced the hydrocarbon concentration by 3827 and 6180 mg/kg, relative to B and C, respectively. Soil toxicity significantly decreased at week 24 compared to the start of the remediation in B, but not in the control. Biochar and control treatments generally showed a similar bacterial community structure throughout the incubation, while the bacterial community structure in BN differed significantly. Biodegradation was found to play a significant role in hydrocarbon removal, as the variation in the bacteria community coincided with differences in hydrocarbon removal between B and BN. The increased removal of hydrocarbons in the BN treatment relative to B coincided with increased and reduced relative abundances of Gordonia and JG30-KF-CM45 genera, respectively. This study showed that NaN3 led to a transient and selective inhibition of bacteria. This study makes an important contribution towards understanding the use of NaN3 in examining the role of biochar in the remediation of diesel-contaminated soil. Overall, we conclude that biochar has the potential to enhance the remediation of diesel-contaminated soil and that biodegradation is the dominant mechanism.

Bioplastic films comprising both plant- and animal-derived proteins have the potential to integrate the optimal characteristics inherent to the specific domain, which offers enormous potential to develop polymer alternatives to petroleum-based plastic. Herein, we present a facile strategy to develop hybrid films comprised of both wheat gluten and wool keratin proteins for the first time, employing a ruthenium-based photocrosslinking strategy. This approach addresses the demand for sustainable materials, reducing the environmental impact by using proteins from renewable and biodegradable sources. Gluten film was fabricated from an alcohol–water mixture soluble fraction, largely comprised of gliadin proteins. Co-crosslinking hydrolyzed low-molecular-weight keratin with gluten enhanced its hydrophilic properties and enabled the tuning of its physicochemical properties. Furthermore, the hierarchical structure of the fabricated films was studied using neutron scattering techniques, which revealed the presence of both hydrophobic and hydrophilic nanodomains, gliadin nanoclusters, and interconnected micropores in the matrix. The films exhibited a largely (>40%) β-sheet secondary structure, with diminishing gliadin aggregate intensity and increasing micropore size (from 1.2 to 2.2 µm) with an increase in keratin content. The hybrid films displayed improved molecular chain mobility, as evidenced by the decrease in the glass-transition temperature from ~179.7 °C to ~173.5 °C. Amongst the fabricated films, the G14K6 hybrid sample showed superior water uptake (6.80% after 30 days) compared to the pristine G20 sample (1.04%). The suitability of the developed system for multilayer 3D printing has also been demonstrated, with the 10-layer 3D-printed film exhibiting >92% accuracy, which has the potential for use in packaging, agricultural, and biomedical applications.

In this study, the efficacy of biochar to mitigate ammonia stress and improve methane production is investigated. Chicken manure (CM) was subjected to high-solid mesophilic anaerobic digestion (15% total solid content) with wood biochar (BC). Wood biochar was further treated using HNO3 and NaOH to produce acid–alkali-treated wood biochar (TBC), with an improvement in its overall ammonium adsorption capacity and porosity. Three treatments were loaded in triplicate into the digesters, without biochar, with biochar and with acid–alkali-treated biochar and maintained at 37 °C for 110 days. The study found a significant improvement in CH4 formation kinetics via enhanced substrate degradation, leading to CH4 production of 74.7 mL g−1 VS and 70.1 mL g−1 VS by BC and TBC treatments, compared to 39.5 mL g−1 VS by control treatments on the 28th day, respectively. However, only the use of TBC was able to prolong methane production during the semi-inhibition phase. The use of TBC also resulted in the highest removal of total ammonia nitrogen (TAN) of 86.3%. In addition, the treatment with TBC preserved the highest microbial biomass at day 110. The presence of TBC also resulted in an increase in electrical conductivity, possibly promoting DIET-mediated methanogenesis. Overall, the acid–alkali treatment of biochar can be a novel approach to improve biochar’s existing characteristics for its utilisation as an additive in anaerobic digestion.

Purpose: This study aimed to compare the conventional eye patch with Occlu-tab—a binocular open-type amblyopia training device—and evaluate their effectiveness in amblyopia treatment. Methods: In this prospective, multi-center study, 40 patients between ages 3 to 12 years, diagnosed with anisometropic amblyopia (refraction difference of both eyes ≥ 2 D, best-corrected visual acuity [BCVA] of the amblyopic eye ≤ 0.1 [logMAR]) were treated with Occlu-tab or conventional eye patch for 1 h per day thrice a week. We compared the visual acuity of both groups before and after 6, 7, and 8 weeks of amblyopia treatment. One-way repeated-measures analysis of variance and Tukey's test were used to compare the visual acuity of both groups pre- and post-treatment. Results: Both groups had significantly improved visual acuity at 6, 7, and 8 weeks compared to that before treatment (all P < 0.001). The improvement in BCVA of the Occlu-tab group (0.33 ± 0.25) was significantly greater than that of the eye patch group (0.16 ± 0.17) after 8 weeks of treatment (P = 0.02). Conclusion: Amblyopia treatment using binocular open game training with Occlu-tab led to greater improvement in visual acuity than that with a conventional eye patch for the same treatment duration.

Background:. In orthopaedic surgery, there are fewer Black or African American (4%) and Hispanic or Latino (4%) residents compared with general surgery, internal medicine, family medicine, and pediatrics (5%-7% Black residents and 7%-9% Hispanic/Latino residents, respectively). There are also fewer underrepresented in medicine minority (URiM) faculty in orthopaedic surgery (6.1%) compared with general surgery (8.9%), otolaryngology (7.8%), internal medicine (9.7%), and obstetrics and gynecology (15.6%). Identifying program characteristics that are associated with the percentage of URiM residents could reveal strategies for improving diversity. Methods:. Using Association of American Medical Colleges orthopaedic resident and faculty race/ethnicity data from 2007 to 2016, we analyzed the racial diversity of 166 of 207 residency programs. The primary outcome was program racial diversity, measured as the percentage of URiM residents per program. The top quartile of programs was compared with the other quartiles. Characteristics analyzed included percentage of URiM faculty, affiliation with a university/top 40 medical school/top 40 orthopaedic hospital, geographic region, city type, and city size. We used a multivariable linear regression model to evaluate program characteristics associated with diversity and a linear mixed-effects model with program-specific random effects to evaluate time trends. Results:. The mean percentage of URiM residents per program was 9.3% (SD = 10.5%). In the top quartile of programs, URiM residents composed 20.7% ± 2.5% of the program compared with 5.8% ± 0.3% in other quartiles (p < 0.001). After adjusting for program and faculty size, the only factor associated with the number of URiM residents per program was the number of URiM faculty. For every 5 additional URiM faculty members, there was an associated increase in the number of URiM residents per program by 3.6 (95% confidence interval [CI]: 2.3-5.0). There was a small but statistically significant annual increase in the percentage of URiM residents per program of 0.207 (95% CI: 0.112-0.302) percentage points during the study period. Conclusion:. URiM representation remains low among orthopaedic residents. Efforts to increase the URiM faculty base represent a potential strategy for programs to increase URiM representation among residents by attracting more diverse applicants.

Biogas production from wastewater is one way that industrial sites can work towards the UN Sustainable Development Goals, while recovering a valuable resource. The objective of this study was to investigate the suitability of data collected by municipal wastewater service providers as a method of classifying and screening waste producers as potential sites for biogas resource recovery by anaerobic digestion. Industrial wastewater samples, including raw effluent and treated waste ready for discharge, were examined, and biomethane potential assays performed. Results of chemical analysis and lab-scale digestion were compared to historical service provider data, and patterns were observed. Biomethane yields of up to 357 mL/gVS and 287mL/gVS were achieved from raw and treated effluent respectively. Digestion at the top four prospects could produce over 4690 GJ of methane and save $47,000 in natural gas costs, offsetting 490 tonnes of CO2 equivalent annually. These streams, from logistics, waste management, food and animal product businesses, combined high levels of degradable substrates and low levels of inhibitory components. While it is unlikely that this type of screening program can be completely accurate, certain parameters, including high sodium concentration, are applicable for discounting the potential for biogas production. This knowledge can be a valuable tool in the process of selecting sites for future resource recovery, therefore increasing the uptake of these processes, resulting in economic, environmental, and climate change mitigation benefits.

Anaerobic digestion has attracted great interest for use in the management of organic wastes and the production of biomethane. However, this process is facing challenges, such as a high concentration of ammonia nitrogen, which affects the methanogenesis process and, thus, the production of methane. This study investigates the use of biosolid-derived biochar for mitigating ammonia stress and improving methane production during the anaerobic digestion of chicken manure, using both pristine biochar and biochar modified with a potassium hydroxide (KOH) solution. Batch mesophilic anaerobic digestion (37 °C) was carried out over 18 days. When compared to chicken-manure-only controls, a significant increase in methane formation was observed in the digesters amended with biochar and KOH-modified biochar, producing 220 L kg−1 volatile solids (VSs) and 262 L kg−1 VSs of methane, respectively, compared to 139 L kg−1 VSs from the control digesters. The use of biochar and KOH-modified biochar resulted in a significant reduction of 8 days in the lag phase. The total ammonia nitrogen (TAN) concentration was reduced in the digesters with biochar and KOH-modified biochar by 25% and 35.5%, respectively. The quantitative polymerase chain reaction (QPCR) data revealed that the number of 16S rRNA gene copies was around 50,000 and 41,000 times higher in the biochar and KOH-modified biochar digesters, respectively, compared to the control digesters on day 18. The taxonomic profiles indicated that the BC and KOH-BC digesters contained a mixture of methanogenic pathways, including acetoclastic (Methanosaetaceae), hydrogenotrophic (Methanosarcinaceae), and methylation (Methanofastidiosaceae). This mix of pathways suggests a more robust archaeal community and, hence, more efficient methanogenesis. The results show that the addition of biosolids biochar enhances anaerobic digestion, mitigates ammonia stress to methanogens, and significantly increases biogas production.

Petroleum hydrocarbons represent one of the most common soil contaminants, whose presence poses a significant risk to soil biota and human health; for example, in Europe, hydrocarbon contamination accounts for more than 30% of contaminated sites. The use of biochar as a proposed alternative to the conventional remediation of soil contaminated with petroleum hydrocarbons has gained credence in recent times because of its cost-effectiveness and environmentally friendly nature. Biochar is a carbonaceous material produced by heating biomass in an oxygen-limited environment at high temperature. This review provides an overview of the application of biochar to remediate petroleum hydrocarbon-contaminated soils, with emphasis on the possibility of biochar functioning as a biostimulation agent. The properties of biochar were also examined. Furthermore, the mechanism, ecotoxicological impact and possible factors affecting biochar-based remediation are discussed. The review concludes by examining the drawbacks of biochar use in the remediation of hydrocarbon-contaminated soils and how to mitigate them. Biochar impacts soil microbes, which may result in the promotion of the degradation of petroleum hydrocarbons in the soil. Linear regression between bacterial population and degradation efficiency showed that R2 was higher (0.50) and significant in treatment amended with biochar or both biochar and nutrient/fertiliser (p

Category: Trauma Introduction/Purpose: Pilon and unstable ankle fractures are often treated initially with an external fixator (ex-fix) due to soft tissue concerns. Typically, the second stage involves open reduction internal fixation of the fracture as the definitive management. Ex-fix application in the emergency department (ED) has been described previously. We aimed to determine if an ex-fix applied in the ED would have any difference in rate of ex-fix revision, deep infection, and hospital length of stay when compared to an ex-fix that is applied in the operating room (OR). Methods: This is a retroscpective, case-cohort study performed at an urban, level-1 trauma center. Using CPT codes in our billing database, we identified all patients from 2011-2015 who had operative fixation of pilon (AO classification 43B or 43C) or unstable ankle fractures (AO classification 44C) and had application of an ex-fix (either ED or OR) prior to definitive fixation. Patients with open injury, those placed in ex-fix at outside institutions and those treated definitively with ex-fix were excluded. Results: Ninety-six patients met the inclusion criteria. Average age was 47 years and 54 (56%) were male. Thirty-three patients had ex-fix placed in the OR and 63 patients had ex-fix placed in the ED. Post-surgical complications (prominent implant, nonunion, deep infection, DVT, loss of reduction) were seen in 6/33 in the ED and 8/63 in the OR group (χ 2 =0.44, p=0.51). Deep infections occurred in 2/33 OR ex-fix and 5/63 ED ex-fix patients (χ 2 =0.137, p=0.71, OR= 1.4 [95% CI = 0.25 to 7.5]). Revision ex-fix for loss of reduction was performed 4/33 in the OR group and 10/63 in the ED ex-fix group (χ 2 =0.296, p=0.59). Mean length of stay was 14 days for the OR and 13 days for the ED group (p=0.35). Conclusion: We found no significant difference in post-surgical complications (surgical or infectious) or ex-fix revision rates for an ex-fix placed in ED compared to one placed in the OR. Total hospital days were similar in both groups. Prospective studies are needed to validate this method of provisional stabilization in the ED; however, these results indicate that the ED ex-fix is equally efficacious to an OR ex-fix.

Charcoal briquettes are inexpensive solid fuels made from carbonized biomass. The potential of converting water hyacinth (Eichhornia crassipes) charcoal into briquettes with molasses as binder was investigated in this study. Dried water hyacinth was carbonized at a temperature between 350°C to 500°C in a fabricated fine biomass carbonizer. A solution containing 80% by weight molasses was used in the production of briquettes having different charcoal/molasses ratios of 40:60, 30:70, and 20:80. Each briquette was characterized in terms of bulk density, calorific value, compressive strength, proximate analysis and micro-structure by Scanning Electron Microscopy. Charcoal briquettes were tested for their flammable characteristics through their burning rates and ignition time. Altering the molasses to charcoal ratio affected the quality and characteristics of the briquettes. Volatile combustible matter and fixed carbon increased with increasing amount of binder while ash content decreased. The 30:70 charcoal/molasses ratio produced the highest calorific value (16.6 MJ/kg) and compressive strength (19.1 kg/cm2). The results have shown the potential of converting water hyacinth into an alternative fuel source.

In recent times, there has been increased focus on a holistic approach to soil remediation with consideration of social, economic and environmental factors. Consequently, there is a demand from practitioners and regulators alike for suitable ways to measure ancillary outcomes, for example, effects on soil quality. Here we show that biochar, when applied to land to remediate lead (Pb)-contaminated soils, can lead to environmental improvements not realized by adding mined or manufactured phosphates. Here, we study a Pb-contaminated soil amended with two phosphate fertilizers (slow- and fast-release) and with biochars produced from poultry litter and from biosolids at three temperatures (300 °C, 400 °C and 500 °C). The results show that, unlike the fast-release P fertilizer, biochars did not result in an increase in the amount of leachable P that could be released into the environment. Biochars prepared at 500 °C presented a higher value of the integrative geometric mean of soil enzyme activity, compared to the P fertilizers. Overall, our research shows that biochars, particularly those prepared at the higher temperature tested, are a suitable alternative to P fertilizers as an integrative remediation strategy in Pb-contaminated soils, enabling soil biological restoration.

Background and Aim: Central corneal thickness (CCT) of term and preterm infants in Indian population is not known. We did a prospective noninterventional study to measure the CCT in term and preterm infants. Materials and Methods: An ultrasonic pachymeter was used. The data regarding the date of birth, expected date of delivery, birth weight were recorded. The preterm and the term infants were followed up at 8 weeks, 20 weeks and at 1-year. Results: A total of 85 (170 eyes) children were included in the study. The mean age was 264.6 ± 21.8 days postconception. The mean birth weight and CCT were 1834.4 ± 512.1 g and 595.8 ± 72.4 μ respectively. A comparison of CCT on the basis postgestational age showed a mean thickness of 620.7 ± 88.8 and 574.4 ± 78.3 μ in the 260 days age groups respectively. The difference was statistically significant (Student′s test, P = 0.002). The CCT of preterm infants (