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Biochar-based slurry is a fossil-free-liquid fuel derived from a renewable source, biomass. This study aims to examine the properties of this fuel as an alternative to coal-water slurries. The slurries were produced by suspending 40 wt% biochar in a solution made of water and a surfactant. Two biochar types from chemically treated and untreated rice straw (RS) were utilized to assess the impact of particle-particle interactions and biochar physicochemical composition on slurry properties, including stability, rheology, and heating value. Additionally, three particle size distributions (PSD), two unimodal and a bimodal, were used to analyze the effect of PSD on the abovementioned properties. All slurries had an average energy content of 7.32 ± 0.27 MJ/kg. The stability of the slurry was higher for fine particles from treated RS with unimodal PSD (Dv50 8.8 ± 0.68 µm). However, slurries containing fine and coarse particles with bimodal PSD (Dv50 15.8 ± 0.64 µm) had relatively lower apparent viscosities of 342.1 and 336.55 mPa.s at a shear rate of 100 s-1 for slurries made of biochar from treated and untreated RS, respectively. Slurries containing coarse particles from treated and untreated RS with unimodal PSD (Dv50 18.6 ± 0.32 µm) led to higher viscosities and particle settling rates. Biochar morphology and chemical surface constitution significantly influenced slurry stability, while PSD greatly impacted rheological results.

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INTRODUCTION: The COVID-19 pandemic has been challenging for healthcare systems in the United States and globally. Understanding how the COVID-19 pandemic has impacted emergency departments (EDs) and patient outcomes in a large integrated healthcare system may help prepare for future pandemics. Our primary objective was to evaluate if there were changes to ED boarding and in-hospital mortality before and during the COVID-19 pandemic. METHODS: This was a retrospective cohort study of all patients ages 18 and over who presented to one of 17 EDs (11 hospital-based; 6 freestanding) within our healthcare system. The study timeframe was March 1, 2019- February 29, 2020 (pre-pandemic) vs. March 1, 2020-August 31, 2021 (during the pandemic). Categorical variables are described using frequencies and percentages, and p-values were obtained from Pearson chi-squared or Fisher's exact tests where appropriate. In addition, multiple regression analysis was used to compare ED boarding and in-hospital mortality pre-pandemic vs. during the pandemic. RESULTS: A total of 1,374,790 patient encounters were included in this study. In-hospital mortality increased by 16% during the COVID-19 Pandemic AOR 1.16(1.09-1.23, p < 0.0001). Boarding increased by 22% during the COVID-19 pandemic AOR 1.22(1.20-1.23), p < 0.0001). More patients were admitted during the COVID-19 pandemic than prior to the pandemic (26.02% v 24.97%, p < 0.0001). Initial acuity level for patients presenting to the ED increased for both high acuity (13.95% v 13.18%, p < 0.0001) and moderate acuity (60.98% v 59.95%, p < 0.0001) during the COVID-19 pandemic. CONCLUSION: The COVID-19 pandemic led to increased ED boarding and in-hospital mortality.

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INTRODUCTION: Freestanding Emergency Departments (FEDs) have grown in number and understanding their impact on the healthcare system is important. Sepsis causes significant morbidity and mortality and identifying how FEDs impact sepsis morbidity and mortality has not been studied. The objective of this study was to determine if there is a difference in in-hospital mortality for sepsis patients who present initially to FEDs compared to a hospital-based ED. METHODS: This was a retrospective cohort of adult patients seen at a hospital-based ED or one of three FEDs within a large hospital system from 1/1/2018-10/31/2020. We included those who were diagnosed with sepsis, severe sepsis or septic shock and evaluated ED throughput measures, in-hospital mortality, and hospital length of stay. Categorical variables are presented as frequencies and percentages. Continuous variables are presented as mean and standard deviations or median and quartiles depending on distribution. Multiple logistic regression was fit to compare in-hospital mortality rates between the two groups. Variables controlled for included Charlson Comorbidity Index, race, gender, insurance, and sepsis severity. Wilcoxon rank sum tests were used to compare the time metrics. RESULTS: There were 1955 patients included in the study. Mean age of participants was 61.9 at the FEDs vs 63.7 at the HBED. Majority of the participants were white; 88.2% at the FED vs. 77.3% at the HBED; and male 49.0% at the FED vs. 51.1% at the HBED. Most patients had Medicare; 45.4% at the FED vs. 58.3% at the HBED. In-patient mortality rate was significantly lower for patients that presented to FEDs compared to HBED (95%CI 0.13-0.46) adjusted odds ratio 0.24. Time to IV fluids, time to lactate, time to blood cultures, time to ED disposition, ED LOS, time to arrival on the inpatient unit were all significantly lower for FEDs vs HBED (p < 0.05). CONCLUSION: Patients presenting to FEDs for sepsis, severe sepsis and septic shock had lower inpatient mortality, quicker treatment times, and were transferred and admitted to the hospital faster than patients seen at a HBED.

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Major agricultural solid waste, rice husk (RH)-based mesoporous materials were prepared by potassium hydroxide (KOH) treatment of RH and RH hydrochar (RHH) produced at 180 °C with 20 min reaction time. In this study, RH was treated with three different methods: RH activation by KOH (KOH-RH), RH activation by KOH-aqueous silver (Ag)-shell nanoparticle (AgNP) incorporation followed calcination at 550 °C for 2 h (AgNP-KOH-RH) and hydrothermally carbonized RH activation by KOH (KOH-RHH). The main objective of this study was to determine the effect of KOH activation with different synthesis approaches and compare the characterization results of RH based porous material to identify the potential adsorbent application for wastewater treatment. Therefore, after activation in different methods, all interactive properties such as elemental, chemical, structural, morphological, and thermal analyses were investigated comprehensively for all samples. The crystallinity peak intensity around 22°λ at the angle of diffraction of 2θ confirmed the presence of silica, higher stability of the material, and removal of organic components during the KOH activation. AgNP-KOH-RH and KOH-RHH presented high porosity on the outer surface. The presence of negligible volatile matter in KOH-RHH by TGA demonstrated the decomposition of organic compound. Very high ratio of aromatic carbon and lignin content by FTIR and XPS analysis in both AgNP-KOH-RH and KOH-RHH showed these two samples have improved stability. Very high negative surface charge (zeta potential) in AgNP-KOH-RH (-43.9 mV) and KOH-RHH (-43.1 mV) indicated the enhanced water holding capacity. Surface area for all experimented porous materials has been enhanced after KOH activation, where KOH-RHH demonstrated the maximum surface area value, 27.87 m2/g. However, AgNP-KOH-RH presented maximum pore diameter, 18.16 nm, and pore volume, 0.12 cm3/g. Hence, it can be concluded that both KOH-RHH and AgNP-KOH-RH have the potential to be implemented as wastewater adsorbents.

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Myocarditis following mRNA COVID-19 vaccination has recently been reported to health authorities in the United States and other countries. Cases predominately occur in young adult males within four days following the second dose of either the Moderna (mRNA-1273) or Pfizer-BioNTech (BNT162b2) vaccines. Although the number of cases reported have been small in comparison with the large number of people vaccinated, myocarditis may be a rare adverse reaction to the COVID-19 vaccination that is now only becoming apparent due to the widespread use of the vaccine. In this article, we present a case of a 20-year-old male with no prior medical history who presented to the emergency department (ED) with chest pain. He had received the BNT162b2 vaccine two days prior to his presentation to the ED. The patient had an elevated troponin at 89 ng/L which increased on repeat examination. His electrocardiogram showed diffuse concave ST segment elevations and a later MRI confirmed the diagnosis of myocarditis. Based on these findings, the patient was diagnosed with myocarditis. The patient had a previous infection with SARS-CoV-2 approximately two months prior to the onset of his symptoms, but since he had fully recovered before the time of his presentation to the ED, it is unlikely that the infection caused the myocarditis. To our knowledge, this is the first published case of myocarditis following BNT162b3 vaccination.

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Guillain-Barré syndrome (GBS) is a rare acute demyelinating syndrome of the peripheral nervous system that is commonly preceded by infection. Vaccinations have also been associated with an increased incidence of GBS, though the risk is low. Caution with revaccination is recommended in patients with a history of GBS. Risks of revaccination compared with the risks of influenza complications should be considered. Patients who experience GBS after vaccination have not been shown to have an increased incidence of recurrent GBS after the influenza vaccine, though evidence is limited. We report a case of recurrent GBS in a patient following the influenza vaccine.

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The recent implication of circular economy in Australia spurred the demand for waste material utilization for value-added product generations on a commercial scale. Therefore, this experimental study emphasized on agricultural waste biomass, rice husk (RH) as potential feedstock to produce valuable products. Rice husk biochar (RB) was obtained at temperature: 180 °C, pressure: 70 bar, reaction time: 20 min with water via hydrothermal carbonization (HTC), and the obtained biochar yield was 57.9%. Enhancement of zeta potential value from - 30.1 to - 10.6 mV in RB presented the higher suspension stability, and improvement of surface area and porosity in RB demonstrated the wastewater adsorption capacity. Along with that, an increase of crystallinity in RB, 60.5%, also indicates the enhancement of the catalytic performance of the material significantly more favorable to improve the adsorption efficiency of transitional compounds. In contrast, an increase of the atomic O/C ratio in RB, 0.51 delineated high breakdown of the cellulosic component, which is favorable for biofuel purpose. 13.98% SiO2 reduction in RB confirmed ash content minimization and better quality of fuel properties. Therefore, the rice husk biochar through HTC can be considered a suitable material for further application to treat wastewater and generate bioenergy.

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Polymer composites are fabricated by incorporating fillers into a polymer matrix. The intent for addition of fillers is to improve the physical, mechanical, chemical and rheological properties of the composite. This study reports on a unique polymer composite using hydrochar, synthesised by microwave-assisted hydrothermal carbonization of rice husk, as filler in polylactide matrix. The polylactide/hydrochar composites were fabricated by incorporating hydrochar in polylactide at 5%, 10%, 15% and 20 wt% by melt processing in a Haake rheomix at 170 °C. Both the neat polylactide and polylactide/hydrochar composite were characterized for mechanical, structural, thermal and rheological properties. The tensile modulus of polylactide/hydrochar composites was improved from 2.63 GPa (neat polylactide) to 3.16 GPa, 3.33 GPa, 3.54 GPa, and 4.24 GPa after blending with hydrochar at 5%, 10%, 15%, and 20%, respectively. Further, the incorporation of hydrochar had little effect on storage modulus (G') and loss modulus (G″). The findings of this study reported that addition of hydrochar improves some characteristics of polylactide composites suggesting the potential of hydrochar as filler for polymer/hydrochar composites.

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The process parameters of microwave-induced hydrothermal carbonization (MIHTC) play an important role on the hydrothermal chars (hydrochar) yield. The effect of reaction temperature, reaction time, particle size and biomass to water ratio was optimized for hydrochar yield by modeling using the central composite design (CCD). Further, the rice straw and hydrochar at optimum conditions have been characterized for energy, chemical, structural and thermal properties. The optimum condition for hydrochar synthesis was found to be at a 180 °C reaction temperature, a 20 min reaction time, a 1:15 weight per volume (w/v) biomass to water ratio and a 3 mm particle size, yielding 57.9% of hydrochar. The higher heating value (HHV), carbon content and fixed carbon values increased from 12.3 MJ/kg, 37.19% and 14.37% for rice straw to 17.6 MJ/kg, 48.8% and 35.4% for hydrochar. The porosity, crystallinity and thermal stability of the hydrochar were improved remarkably compared to rice straw after MIHTC. Two characteristic peaks from XRD were observed at 2θ of 15° and 26°, whereas DTG peaks were observed at 50⁻150 °C and 300⁻350 °C for both the materials. Based on the results, it can be suggested that the hydrochar could be potentially used for adsorption, carbon sequestration, energy and agriculture applications.

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PURPOSE: Most MR-guided catheter-based procedures, and imaging of patients with implanted medical devices, are currently contraindicated due to a significant risk of heating associated with induced RF currents. The induced RF current produces a corresponding artifact which can be used to remotely characterize current and safely predict RF heating. Application of this remote technique in vivo to safely quantify RF heating risk may allow for execution of many scans currently contraindicated. Sources of phase other than induced RF current may present difficulty in practical in vivo. METHODS: A custom ultra-short echo time (UTE) sequence was developed to minimize unwanted phase contributions. A phantom experiment was performed to compare current characterization using a stock gradient-echo (GRE) sequence and the custom UTE sequence following calibration of the temperature measurement apparatus using a previously published heating prediction technique. Animal experiments were used to investigate the feasibility of using the UTE sequence to quantify RF heating. RESULTS: Current characterization and heating prediction with a stock GRE sequence was equivalent to that with the custom UTE sequence. Heating measurements and image-based predictions in animal experiments agreed within error in all experiments. CONCLUSION: Through comparison of measured heating and image-based prediction, feasibility of using a custom UTE sequence to quantify RF heating risk in vivo was demonstrated.

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The process parameters of microwave hydrothermal carbonization (MHTC) have significant effect on yield of hydrochar. This study discusses the effect of process parameters on hydrochar yield produced from MHTC of rice husk. Results revealed that, over the ranges tested, a lower temperature, lower reaction time, lower biomass to water ratio, and higher particle size produce more hydrochar. Maximum hydrochar yield of 62.8% was obtained at 1000 W, 220 °C, and 5 min. The higher heating value (HHV) was improved significantly from 6.80 MJ/kg of rice husk to 16.10 MJ/kg of hydrochar. Elemental analysis results showed that the carbon content increased and oxygen content decreased in hydrochar from 25.9 to 47.2% and 68.5 to 47.0%, respectively, improving the energy and combustion properties. SEM analysis exhibited modification in structure of rice husk and improvement in porosity after MHTC, which was further confirmed from BET surface analysis. The BET surface area increased from 25.0656 m2/g (rice husk) to 92.6832 m2/g (hydrochar). Thermal stability of hydrochar was improved from 340 °C for rice husk to 370 °C for hydrochar.

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OBJECTIVE: MRI in the area of cardiovascular catheter-based interventional procedures is an active field. A common intervention-revascularization of chronic total occlusions, requires a conductive guidewire for revascularization. The mechanical properties of guidewires are paramount to the successful execution of such procedures. Furthermore to benefit from MRI techniques, additional conductors are required to transmit signal from the tip of a catheter. Long thin conductors in MRI systems pose a safety risk in the form of RF heating due to induced RF currents on the conductors. Unfortunately many existing techniques to mitigate this risk require physical modification of the conductors, inevitably resulting in detrimental mechanical tradeoffs in the guidewire. This manuscript proposes a novel application and miniaturization of an existing device, the floating RF trap. The RF trap couples strongly to any thin conductor passing through the trap lumen inducing significant series impedance. This results in reduction of induced RF currents, and thus, heating. METHODS AND RESULTS: This study shows theoretical and experimental analysis of induced impedance as well as theoretical reduction in heating due to various distributions of traps along the length of a catheter. Results of measuring induced current and heating in phantom experiments are also presented. Through comparison with commercial simulation packages and results of phantom experiments, it is shown that miniaturized RF traps can be modeled accurately, including their induced series impedance and effect on induced RF current. CONCLUSION AND SIGNIFICANCE: It was demonstrated that floating RF traps present a feasible method to mitigate RF heating while maintaining important mechanical properties of guidewires.

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BACKGROUND: It has been speculated that freestanding emergency departments (FEDs) draw more affluent, better-insured patients away from urban hospital EDs. It is believed that this leaves urban hospital-based EDs less financially secure. OBJECTIVE: We examined whether the distribution of patients with four types of insurance (self-pay, Medicaid, Medicare, and private) at the main ED changed after opening three affiliated FEDs, and whether the insurance type distribution was different between main ED and FEDs and between individual FEDs. METHODS: A retrospective analysis of insurance status of all patients presenting to our EDs from July 2006 through August 2013. Insurance was divided into self-pay, Medicare, Medicaid, and private insurance across three time periods, which reflect the sequential opening of each FED. Insurance types for each facility were compared for individual time periods and across time periods. χ2 was used to analyze the data. RESULTS: In the three studied time frames (periods B, C, and D), there were less privately insured patients and more self-pay, Medicaid, and Medicare patients at the main than at each FED (p < 0.001). Insurance types were significantly different between each of the three FEDs and the main ED (p < 0.001) and between each of the three FEDs (p < 0.001). CONCLUSIONS: There were less privately insured patients and more self-pay, Medicaid, and Medicare patients at the main ED compared to the FEDs. Privately insured patients decreased at both the FEDs and main ED during the study. Insurance distribution was significantly different between the main ED, and three FEDs, and between individual FEDs.

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Wilms tumor and nephroblastomatosis are associated with syndromic conditions including hemihyperplasia. Hemihyperplasia is genetically heterogeneous and may be the result of genomic abnormalities seen in Beckwith-Wiedemann syndrome, mosaic chromosome or genomic abnormalities, or somatic point mutations. Somatic missense mutations affecting the PI3K-AKT-MTOR pathway result in segmental overgrowth and are present in numerous benign and malignant tumors. Here, we report a fourth patient with asymmetric overgrowth due to a somatic PIK3CA mutation who had nephroblastomatosis or Wilms tumor. Similar to two of three reported patients with a somatic PIK3CA mutation and renal tumors, he shared a PIK3CA mutation affecting codon 1047, presented at birth with asymmetric overgrowth, and had fibroadipose overgrowth. Codon 1047 is most commonly affected by somatic mutations in PIK3CA-related overgrowth spectrum (PROS). While the fibroadipose overgrowth phenotype appears to be common in individuals with PIK3CA mutations at codon 1047, individuals with a clinical diagnosis of Klippel-Trenaunay syndrome or isolated lymphatic malformation also had mutations affecting this amino acid. Screening for Wilms tumor in individuals with PROS-related hemihyperplasia may be considered and, until the natural history is fully elucidated in larger cohort studies, may follow guidelines for Beckwith-Wiedemann syndrome, or isolated hemihyperplasia. It is not known if the specific PIK3CA mutation, the mosaic distribution, or the clinical presentation affect the Wilms tumor or nephroblastomatosis risk in individuals with PROS. © 2016 Wiley Periodicals, Inc.

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BACKGROUND: Freestanding emergency departments (FEDs) continue to grow in number and more research is needed on these facilities. OBJECTIVE: We sought to characterize the types of injuries and patients who initially presented to two FEDs and were transferred to the main tertiary care ED for trauma team consult and admission. METHODS: This retrospective cohort descriptive study examined medical records of adult trauma patients who were initially seen at an FED and then transferred to the main ED. All patients who received a trauma consultation were included. Data collection included demographics, initial mode of transport to the ED, injury, mechanism of injury, ED, hospital course and outcome. RESULTS: Mean age was 61.8 ± 23.8, 96.7% were Caucasian and 52.5% were male. Mode of transport to the FEDs included private vehicle (46.4%) and emergency medical services (53.6%). The main injury mechanisms were fall from standing (51.9%) and fall from an object (16%). A total of 12.7% were from motor vehicle accidents and 6.6% presented from bicycle and all-terrain vehicle accidents. Blunt traumatic injuries accounted for 97.8% (n = 177) patients. Computed tomography scanning was performed on 90.1% of patients. Median ED length of stay was 189 min. Mean hospital length of stay was 3 days and 2.2% (n = 4) of patients died from their injuries. CONCLUSIONS: Understanding the patients and traumatic injuries that present to FEDs will guide training and identify resources needed for patients requiring additional care at a trauma center.

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PURPOSE: Many procedures involving catheters and implanted medical devices could benefit from MRI guidance but are currently contraindicated due to risk of significant heating near linear conductive structures. A priori safety prediction is impossible in vivo and thus, safety is typically investigated in vitro by directly measuring temperature rise. Existing methods of investigating safety are inflexible and provide few data. Furthermore, they are fundamentally limited because dangerous temperatures rises can only be investigated if induced. A method of remotely predicting safety is necessary for ensuring safety in patients. THEORY AND METHODS: Electric current induced on the metallic object causes any dangerous heating; thus a remote method of safely characterizing the induced radiofrequency (RF) current distribution would suffice to evaluate safety assuming conservative estimates for local tissue properties. Here we propose a method of analyzing induced phase artifacts seen in low-specific absorption rate characterization images, to determine induced current on an interventional device. This induced current distribution can then be used to predict RF heating behavior under application of any other imaging sequence. RESULTS: This method has been successfully used to reproduce numerical simulations in a phantom. Furthermore, the heating behavior around a conductive wire produced by a scan other than that used to characterize current was successfully predicted. CONCLUSION: It has been shown in phantom experiments that remote current characterization can safely prevent dangerous scans as well as enable safe scans that previously would not have been attempted.

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BACKGROUND: Freestanding emergency departments (FEDs) introduce a challenge to physicians who care for the patient with an ST-segment elevation myocardial infarction (STEMI) because treatment is highly time dependent. FEDs have no percutaneous coronary intervention (PCI) capabilities, which necessitates transfer to a PCI-capable facility or fibrinolysis. STUDY OBJECTIVE: Our aim was to determine the proportion of STEMI patients who arrived to an FED and were subsequently transferred for PCI and met the door-to-balloon reperfusion guidelines of 90 min. METHODS: This was a dual-center retrospective cohort review of all patients 18 years and older who were diagnosed with an STEMI and presented to the main hospital-affiliated FEDs. Electronic medical records and emergency medical services documentation were reviewed for all cases since the opening of the FEDs in July 2007 and August 2009, respectively. Key time points were abstracted and statistical evaluation was performed using Fisher's exact test. RESULTS: A total of 47 patients met inclusion criteria. Median door-to-transport time was 34 min (interquartile range [IQR] 15 min). Median transport time from the FEDs to the main hospital catheterization laboratory was 21 min (IQR 5 min). Median arrival at the catheterization laboratory-to-balloon time was 25 min (IQR 13 min). Median total door-to-balloon time was 83 min (IQR 10.5 min), with 78.7% meeting the American Heart Association's recommended guidelines of ≤ 90 min. CONCLUSION: STEMI patients initially seen at two FEDs achieved door-to-balloon time goals of < 90 min.

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A 10-month-old male infant presented to the emergency department (ED) with a chief complaint of weakness, decreased mobility, and regression of motor milestones over a period of 6 days. Significant medical history included a Roseola infection 5 weeks before ED presentation. The patient's pediatrician and chiropractor had both previously diagnosed the patient with strains and sprains. After progression of symptoms, the patient presented to the ED and was discharged home to follow up as an outpatient. The patient subsequently returned to the ED and was admitted to neurology with concern for Guillain-Barré syndrome, which was later confirmed after inpatient workup. The patient was successfully treated and released. Guillain-Barré represents a spectrum of acute immune mediated polyneuropathies. There are several variant forms provoked by infection that precedes the onset of symptoms. Diagnosis and management of Guillain-Barré in the ED will be reviewed, along with the importance of early pediatric intensive care involvement for children presenting with signs of flaccid quadriparesis; rapidly progressive weakness; impending respiratory failure; bulbar palsy; and, most importantly, autonomic cardiovascular instability. Guillain-Barré is rare in children younger than 2 years; however, it must be considered in the differential diagnosis of any patient who presents with progressive weakness and history of a recent infection. It is important to recognize the variety and severity of neurologic symptoms associated with Guillain-Barré across a spectrum, especially with the diagnostic difficulties associated with the pediatric population.

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We present a case of Eagle syndrome in a 77-year-old woman with associated aneurysm and nontraumatic styloid process fracture, without history of tonsillectomy, who presented to the emergency department. The first set of symptoms associated with the elongation of the temporal styloid process and/or the calcification of the stylomandibular or stylohyoid ligaments was described by Eagle in 1937. Classically, unilateral pain in the oropharynx radiating to the neck and face that is exacerbated by head turning and neck rotation is characteristic of Eagle syndrome. However, styloid process elongation and stylohyoid calcification found in Eagle syndrome may also present with vascular symptomsthrough impingement and injury of the carotid arteries. Eagle syndrome is a rare but important differential that the emergency physician must consider in a patient with unilateral neck pain and positional neurological symptoms with head turning and in posttonsillectomy patients. Patients with medical history of Eagle syndrome presenting with neck pain and especially neurological symptomsmust be thoroughly evaluated for carotid and jugular venous injury. Specifically, the decision to obtain computed tomography and computed tomographic angiography to evaluate for carotid artery injury is important for patient management and disposition.

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