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This study explores a strategy to mitigate capacity fading in secondary batteries, which is primarily attributed to side reactions caused by residual Li impurities (LiOH or Li2CO3) on the surface of Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) layered cathode materials. By applying a 1.5 wt% Co3(PO4)2 coating, we successfully formed a thin and stable LiF cathode-electrolyte interface (CEI) layer, which resulted in decreased battery resistance and enhanced diffusion of Li+ ions within the electrolyte. This coating significantly improved the interface stability of NCM811, leading to superior battery performance. Specifically, the discharge capacity of uncoated NCM811 was 190 mA h g-1 at a charge of 4.3 V and a rate of 0.1C, whereas the 1.5Co3(PO4)2/NCM811 exhibited an increased capacity of 213 mA h g-1. Furthermore, the Co3(PO4)2 coating effectively reduced the levels of LiOH and Li2CO3 on the NCM811 surface to only 0.1 %, thereby minimizing adverse side reactions with the electrolyte salt (LiPF6), cation mixing between Ni2+ and Li+, and defects at the NCM811 interface. As a result, battery lifespan was significantly extended. This study presents a robust approach for enhancing battery stability and performance by efficiently reducing residual Li+ ions on the surface of NCM811 through strategic Co3(PO4)2 coating.

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BACKGROUND: Warfarin dosing in cardiac surgery patients is complicated by a heightened sensitivity to the drug, predisposing patients to adverse events. Predictive algorithms are therefore needed to guide warfarin dosing in cardiac surgery patients. OBJECTIVE: This study aimed to develop and validate an algorithm for predicting the warfarin dose needed to attain a therapeutic international normalized ratio (INR) at the time of discharge in cardiac surgery patients. METHODS: We abstracted variables influencing warfarin dosage from the records of 1031 encounters initiating warfarin between April 1, 2011, and November 29, 2019, at St Michael's Hospital in Toronto, Ontario, Canada. We compared the performance of penalized linear regression, k-nearest neighbors, random forest regression, gradient boosting, multivariate adaptive regression splines, and an ensemble model combining the predictions of the 5 regression models. We developed and validated separate models for predicting the warfarin dose required for achieving a discharge INR of 2.0-3.0 in patients undergoing all forms of cardiac surgery except mechanical mitral valve replacement and a discharge INR of 2.5-3.5 in patients receiving a mechanical mitral valve replacement. For the former, we selected 80% of encounters (n=780) who had initiated warfarin during their hospital admission and had achieved a target INR of 2.0-3.0 at the time of discharge as the training cohort. Following 10-fold cross-validation, model accuracy was evaluated in a test cohort comprised solely of cardiac surgery patients. For patients requiring a target INR of 2.5-3.5 (n=165), we used leave-p-out cross-validation (p=3 observations) to estimate model performance. For each approach, we determined the mean absolute error (MAE) and the proportion of predictions within 20% of the true warfarin dose. We retrospectively evaluated the best-performing algorithm in clinical practice by comparing the proportion of cardiovascular surgery patients discharged with a therapeutic INR before (April 2011 and July 2019) and following (September 2021 and May 2, 2022) its implementation in routine care. RESULTS: Random forest regression was the best-performing model for patients with a target INR of 2.0-3.0, an MAE of 1.13 mg, and 39.5% of predictions of falling within 20% of the actual therapeutic discharge dose. For patients with a target INR of 2.5-3.5, the ensemble model performed best, with an MAE of 1.11 mg and 43.6% of predictions being within 20% of the actual therapeutic discharge dose. The proportion of cardiovascular surgery patients discharged with a therapeutic INR before and following implementation of these algorithms in clinical practice was 47.5% (305/641) and 61.1% (11/18), respectively. CONCLUSIONS: Machine learning algorithms based on routinely available clinical data can help guide initial warfarin dosing in cardiac surgery patients and optimize the postsurgical anticoagulation of these patients.

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Background: The short-term clinical outcomes of first-generation thicker-strut durable polymer-based drug-eluting stents (DES) have been widely examined. However, there is a scarcity on qualitative research on the long-term usage of DES that evaluated the thinner strut biodegradable stents for coronary artery disease. Hence, we sought to investigate the long-term safety and performance of thinner strut biodegradable polymer-based BioMime sirolimus-eluting coronary stent system in real-world patients with symptomatic ischemic heart disease. Methods: This was a retrospective, observational, single-center, post-marketing clinical follow-up study. The primary endpoints were the incidence of major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction (MI) attributed to target vessel revascularization (TVR), and target lesion revascularization (TLR) at 1-, 2-, 3- and 4-year follow-ups. The secondary endpoints were cardiac death, MI, TLR, TVR, device and procedural success rates, and stent thrombosis (ST). Results: In all, 1,188 consecutive patients were enrolled, and 1,333 (1,257 de novo and 76 in-stent restenotic lesions) out of 1,565 lesions were treated with the study device. The mean age of patients was 53.26 ± 10.31 years and 86.2% were male. The quantitative coronary angiographic derived mean lesion length and diameter were 29.62 ± 9.62 mm and 3.01 ± 0.29 mm, respectively. The average length and diameter of the study device implanted were 30.89 ± 6.31 mm and 3.17 ± 0.25 mm, respectively. The cumulative incidence of MACE at 1-, 2-, 3-, and 4 years was 0.61%, 1.47%, 2.08%, and 3.40%, respectively, and cumulative deaths due to cardiac causes were 0.61%, 1.13%, 1.22%, and 1.83%, respectively. There were no cases of TLR or TVR at 1-year follow-up. The cumulative rate of TLR at 2-, 3-, and 4 years was 0.35%, 0.87%, and 1.57%, respectively, while that of TVR was 0.61%, 1.47%, and 2.35%, respectively. Three (0.3%) incidences of probable ST occurred during the 6-month follow-up; no new cases were reported further. In subgroup analysis, MACEs were comparable across the long- and short-length stent groups through 4-year follow-up. Conclusions: This long-term study demonstrates the safety and performance of the ultra-thin BioMime sirolimus-eluting stent with satisfactory clinical outcomes in patients with symptomatic ischemic heart disease in real-world scenario.

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The aim of this study was to evaluate the influence of different packaging materials [standard foil: BOPP (biaxially oriented polypropylene)/PET (polyester)/PE (polyethylene) for upper layer, and APET (polyethylene terephthalate)/PE for bottom layer; foil 1: PP (polypropylene)/PET/PE/EVOH (ethylene-vinyl alcohol copolymer)/PE upper layer, and PP/PE/EVOH/PE bottom layer; foil 2: PP/PET/PE/EVOH/PE upper layer, and PA (polyamide)/EVOH/PE bottom layer; foil 3: PP/PET/PE upper layer, and PA/EVOH/PE bottom layer; foil 4: PP/PET/PE upper layer, and PA/PE bottom layer; foil 5: PP upper layer, and PP/PP bottom layer] on the quality of 3 different ripening rennet cheeses packed under different modified atmosphere (MAP) conditions as reflected in particular physicochemical, microbiological, and sensorial changes. The changes were monitored during a period of 90 d of storage at 2°C or 8°C. For Gouda cheese, CO2 content of the headspace of the packages was in the range 35% to 45%, whereas for Maasdamer and Sielski Klasyczny cheeses it was 55% to 65%. Three-way ANOVA showed that the foil type influenced the moisture content of Gouda cheese stored for 90 d at 2°C and for Sielski Klasyczny cheese at 8°C, whereas the moisture content was not dependent on MAP conditions during storage. Moreover, the foil type had a significant effect on free fatty acid changes for Gouda and Sielski Klasyczny cheeses stored at 2°C for 90 d. Sensory attributes changed significantly over storage time at 2°C for all studied cheeses as affected by foil type, whereas there was no effect of MAP conditions. In general, the cheeses packed in standard foil and foil 4 were characterized by the highest values of mean sensory attributes. Time was the most significant factor influencing most changes in physicochemical and sensory attributes of cheeses stored at 2°C and 8°C. The storage temperature did not affect the moisture of the samples during storage. In general, we found an increase in the pH value during storage regardless of storage temperature. It was possible to decrease the thickness of the packaging material from initial 103 and 250 µm (standard foil; lid and bottom, respectively) to 98 and 100 µm (foil 4) without affecting sensory attributes of the product.

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With the rapid development of electronic and communication technology for military radars, the demand for microwave-absorbing materials in the low-frequency range with thin layers is growing. In this study, flexible Co3O4/CC (carbon cloth) composites derived from Co-MOFs (metal-organic frameworks) and CC are prepared using hydrothermal and thermal treatment processes. The flexible precursors of the Co-MOFs/CC samples are calcined with different calcination temperatures, for which the material structure, dielectric properties, and microwave absorption performance are changed. With the increases in calcination temperature, the minimum reflection loss of the corresponding Co3O4/CC composites gradually moves to the lower frequency with a thinner thickness. In addition, the Co3O4/CC composites with the 25 wt% filler loading ratio exhibit the minimum reflection loss (RL) of -46.59 dB at 6.24 GHz with a 4.2 mm thickness. When the thickness is 3.70 mm, the effective absorption bandwidth is 3.04 GHz from 5.84 to 8.88 GHz. This study not only proves that the Co3O4/CC composite is an outstanding microwave-absorbing material with better flexibility but also provides useful inspiration for research on wideband microwave absorption materials below 10 GHz.

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A hematoma is a collection of pooled blood that can be confined to a space under the skin, tissue, or organ. It occurs due to injury to the vasculature arising from trauma, previous surgeries, or vascular defects. Anticoagulants can remarkably increase a patient's risk for hematoma formation. Most hematomas will resolve spontaneously over time, but there are certain instances where surgical intervention becomes necessary. We present a case of a 71-year-old female on anticoagulants who presented to the emergency department (ED) with an expanding hematoma on her right leg after a fall and had to undergo an emergency surgical evacuation. The etiology, appropriate management, and complications of hematomas will also be covered in this paper.

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Reproductive health is a major concern for workers constantly exposed to chemicals at work, especially in developing countries. The problems mainly stemmed from chronic exposure to the chemicals contained in paint thinner, which is mainly toluene, used during automobile painting. Unfortunately, in Indonesia, there is no study on the reproductive health of male workers in automobile workshops, especially in relation to spermatogenesis. This study aimed to explore the possibility of reproductive problems, namely spermatozoa DNA fragmentation, among male workers in an automobile workshop in Malang. We recruited workers who have worked as automobile painters for years at an automobile workshop in Malang and have been chronically exposed to thinner. Semen samples were collected from 15 automobile workshop workers who were married and had children. Twelve office workers were used as the control group. The two groups of semen samples were tested with the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay combined with propidium iodide and analyzed by flow cytometry. The results showed a significant difference between DNA fragmentation of the control group and workshop workers at 14.9% and 47.66%, respectively. Risk factor analysis showed a significant increase in risk factors (p = 0.001). Taken together, chronic exposure to paint thinner in those engaged in painting at the automobile workshop increased the risk of DNA fragmentation in spermatozoa. Our study highlighted the importance of health education for the risked workers on minimization of exposure, which could be recommended to the health policy makers.

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Peritoneal dialysis treatment generates significant amounts of waste for disposal from patients' homes. In Australia, in the days after the onset of the COVID-19 pandemic, waste collection from homes was temporarily stopped. Our patient tried to dispose of his waste by burning the used bags and tubing, using paint thinner as an accelerant. We present a case report of the unusual neurological complication he developed.

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Inhalant abuse is a serious and ever-evolving problem for our society. Inhalants are abused more commonly by teenagers and adolescents. Inhalants such as glue, paint thinners, correction fluid, and nail paint remover are easily available in the market which makes them readily abused. Out of various methods of abuse, huffing (placing a piece of cloth soaked with inhalant is placed in the mouth), bagging (placing head in a polythene bag containing inhalant), and ballooning (balloons filled with inhalant are used for inhaling vapors through the mouth) are most common. Inhalant abuse results in multiple target organ dysfunction with neuritis and brain damage due to the dissolution of the myelin sheath. In acute poisoning cases, it might cause death due to asphyxia and sudden sniffing syndrome. In such cases, various articles containing traces of inhalants could be retrieved from the scene of incidence and to detect these traces become an important facet of the investigation. However, it might be difficult due to the rapid evaporation of inhalants and the formation of reaction product species. In the present study, an attempt has been made to study the effect of three substrates (balloon, cloth, polythene) on component profiles of four paint thinners and four nail paint removers. The study suggests that although some components are retained, there is the formation of a large number of reaction product species and these must be taken into consideration before furnishing the opinion. These reaction product species might also be inhalant specific which must be further explored.

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Colonoscopy is considered a low-risk procedure worldwide. Complications include hemorrhage, bowel perforation, and splenic rupture on rare occasions. The incidence of splenic rupture estimates between 0.00005 and 0.017%. Due to its nonspecific presentation, many cases may be misdiagnosed. We present a 76-year-old female on apixaban for atrial fibrillation who presented to us with sudden-onset, left-sided atraumatic chest pain radiating to the left shoulder, 10/10 in intensity, associated with nausea. The patient underwent an uncomplicated colonoscopy 16 days earlier with the excision of a 1.3 cm polyp. On presentation, her blood pressure was 96/58 mmHg, hemoglobin of 7.2, an international normalized ratio (INR) of 1.6. An abdominal computed tomography scan showed findings suspicious for splenic rupture. In the emergency department, two packed red blood cells (PRBCs) were transfused, and the patient was shifted to the operating room for emergent exploratory laparotomy where a splenectomy was performed for splenic rupture. The patient was discharged six days later without any postoperative complications. We speculate the use of apixaban and our patient's unusual site of pain following splenic rupture to be somehow correlated.

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BACKGROUND: At present, different designs of tooth brushes are available, each one is being claimed to be the best by their manufacturers. There is a need to compare the plaque removal efficacy of the most popular designs. AIM: The aim of the present study was to compare the degree ofplaque removal obtained with the use of two commercially available tooth brushes with round ended and thinner tip bristles. MATERIALS AND METHODS: The study involved 60 subjects within age range 18-40 years, randomly distributed into 2 groups, 30 in each: Group A- round ended bristle, Group B- thinner tip bristle. Turesky, Gilmore, Glickman Modification of Quigley-Hein Plaque Index, (1970), (PI) was assessed at baseline, 2 weeks, 4 weeks, and 6 weeks; and Muhlemann and Son, (1971), Sulcus bleeding index (SBI) at baseline and 2 weeks were assessed in each subject. Scaling was done at 2nd week, 4th week, and 6th week after assessment of parameter. At 4th week the subjects were switched over to another type of brush for crossover evaluation. RESULTS: Over 2 weeks, both the groups showed significant (P < 0.05) reduction in plaque score, better reduction in Group A with mean differences of 0.48 than 0.41 in Group B, though it was insignificant on intergroup comparison (P = 0.09). There was reduction in SBI in both groups with mean difference of 0.50 in Group A and 0.11 in Group B and this was statically insignificant. But on comparison, between the two groups at 2 weeks, statically significant reduction was there in Group A. Brushing with specified brush, after scaling, at 4th week Group A had significantly better plaque control (P < 0.01). Upon crossover analysis, better efficiency of round ended bristles was observed but it did not reach the significance level (P = 0.126). CONCLUSION: Within the limitations of the study, the data derived from the study show that both the toothbrushes had shown decrease in plaque scores. Round ended bristles were more efficient.

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INTRODUCTION: The initial clinical trials for intralesional collagenase Clostridium histolyticum (CCh) injection therapy for Peyronie disease (PD) excluded men on antiplatelet or anticoagulant medications except those on low-dose aspirin. Men with PD who take such medications present a challenging clinical scenario because of a lack of evidence regarding the safety of CCh while on these drugs. AIM: To evaluate safety outcomes among patients continuing anticoagulant and antiplatelet therapy during ongoing intralesional CCh injection treatment for PD. METHODS: An institutional review board approved a database of 187 patients treated with CCh at an academic men's health practice from January 2016 through April 2019 was reviewed. Men on antiplatelet/anticoagulant medications were not instructed to stop these agents. Data on patient demographics, comorbidities, CCh injection details, use or nonuse of antiplatelet/anticoagulant medications, and adverse events were extracted from the electronic medical record. Rates of hematoma formation, bruising, swelling, and corporal rupture were determined. Univariate statistical analysis compared clinical data and adverse events between men on or off antiplatelet/anticoagulant medications. MAIN OUTCOME MEASURE: Statistical comparison of adverse events in those taking or not taking antiplatelet or anticoagulant medications while undergoing intralesional CCh injection therapy for PD. RESULTS: Of 187 men undergoing CCh treatment, 33 (17.6%) were on concomitant antiplatelet or anticoagulant therapy. Aspirin 81 mg alone was the most common pharmacologic agent (58% of men on antiplatelet/anticoagulants); medications also included other antiplatelet drugs, warfarin, and novel oral anticoagulants (NOACs). Men taking blood thinners during intralesional CCh injection therapy experienced no statistical difference in rates of bruising, swelling, or hematoma formation compared with men not on antiplatelet/anticoagulants. No corporal ruptures were observed in either group. Men on antiplatelet or anticoagulant therapy were more likely to be older (64 vs 58 years old, P = 0.005), have hypertension (P = 0.025), and have hyperlipidemia (0.009). CLINICAL IMPLICATIONS: Intralesional CCh injection therapy may be offered to men on antiplatelet/anticoagulant medications without increased risk of adverse events. STRENGTH & LIMITATIONS: This study evaluated the experience of a single surgeon, with a systematic evaluation of adverse events captured in a robust electronic medical record. The retrospective nature of this study limits conclusions but builds upon work performed in the initial clinical trials for CCh. CONCLUSION: Our findings suggest that antiplatelet and anticoagulant medications do not increase the risk of adverse events during intralesional CCh injection therapy for PD. Amighi A, Regets KV, Nork JJ, et al. Safety of Collagenase Clostridium histolyticum Injection Therapy for Peyronie Disease in Patients Continuing Antiplatelet or Anticoagulant Therapy. J Sex Med 2020;17:353-356.

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Current guidelines generally recommend continuation of blood thinning drugs in dermatologic surgery and the previously used "bridging" with subcutaneous or intravenous heparin is obsolete. While the guidelines are increasingly implemented in daily practice, there is still uncertainty concerning the use of the novel direct oral anticoagulants (NOAC = DOAC). In this review, we analyze current developments and formulate concise recommendations for continuation during skin surgery under consideration of individual risk.

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ETHNOPHARMACOLOGICAL RELEVANCE: Cardiovascular diseases are the major cause of mortality and morbidity, causing over 17.9 million deaths a year worldwide. Currently used therapy is often having side effects and expensive, dietary interventions and alternative medicines are required. Clerodendrum colebrookianum has been used to treat cardiac hypertension but anticoagulant potency was not evaluated. AIM OF THE STUDY: To characterize an active anticoagulant fraction (AAFCC) and a 30 kDa fibrin(ogen)olytic serine protease (clerofibrase) isolated from aqueous leave extract of C. colebrookianum. MATERIALS AND METHODS: AAFCC/clerofibrase was subjected to extensive biochemical and pharmacological characterization including LC-MS/MS, amino acid compositional and GC-MS analyses. Interaction between clerofibrase with fibrinogen was studied by spectrofluorometric analysis. In vitro thrombolytic, antiplatelet and cytotoxicity assay were performed. In vivo toxicity, anticoagulant, defibrinogen and antithrombotic activities were determined on Swiss albino mice. RESULTS: The in vitro anticoagulant activity of AAFCC was found to be superior to heparin and clerofibrase and comparable to Nattokinase and warfarin. The proteomics and amino acid composition analyses suggest that clerofibrase is a previously uncharacterized novel plant protease capable of degrading the -αß chains of fibrinogen/fibrin. AAFCC/clerofibrase exerts their anticoagulant action via fibrinogenolytic activity and partially by antiplatelet activity albeit they have no effect on thrombin and FXa inhibition. The spectrofluorometric analysis revealed the binding of clerofibrase to fibrinogen but not to thrombin and FXa. The phytochemical constituents and bioactive components of AAFCC were characterized by biochemical, and GC-MS analyses. The AAFCC and clerofibrase inhibited collagen/ADP-induced mammalian platelet aggregation, showed in vitro thrombolytic activity, and non-cytotoxic to mammalian cells. The AAFCC showed and dose-dependent in vivo plasma defibrinogenating and anticoagulant activities and inhibited k-carrageen-induced thrombus formation in the tails of mice. CONCLUSION: The potent in vivo anticoagulant and antithrombotic effects of AAFCC suggests its pharmacological significance as herbal anticoagulant drug for the prevention and/or treatment of hyperfibrinogenemia- and thrombosis associated cardiovascular disorders.

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A large parallax-free gas diffraction meter based on a thinner-THGEM (thick gaseous electron multiplier) has been developed at the Beijing Synchrotron Radiation Facility (BSRF). A thinner-THGEM of thickness 200 µm is adopted, which can be shaped into a curve to eliminate parallax-error effects. The detector is designed to have a 48° open angle positioned 20 cm from the powder samples. A front-end electronics board with 128 channels direct-current mode was adapted for the 8 keV BSRF beamline with 0.2 ns/100 ns stable duty cycle. Two powder samples, TiO2 and SnO2, were tested separately. The measured spectra with an angular resolution of 0.148 ± 0.081° are consistent with the data from the powder diffraction file. Combining the gas gain of the thinner-THGEM with the electronic circuit dynamic range, a very broad dynamic range of about 107 could be obtained.

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Thinners are highly toxic chemicals widely employed as organic solvents in industrial and domestic use. They have psychoactive properties when inhaled, and their chronic abuse as inhalants is associated with severe long-term health effects, including brain damage and cognitive-behavioral alterations. Yet, the sites and mechanisms of action of these compounds on the brain are far from being fully understood. Here, we investigated the consequences of paint thinner inhalation in adult male mice. Depression-like behaviors and an anxiolytic effect were found following repeated exposure in chronic treatments lasting 12 weeks. Both subchronic (6 weeks) and chronic treatments impaired learning and memory functions, while no changes were observed after acute treatment. To investigate possible molecular/structural alterations underlying such behavioral changes, we focused on the hippocampus. Notably, prolonged, but not acute thinner inhalation strongly affected adult neurogenesis in the dentate gyrus (DG), reducing progenitor cell proliferation after chronic treatments and impairing the survival of newborn neurons following both chronic and subchronic treatments. Furthermore, a down-regulation in the expression of BDNF and NMDA receptor subunits as well as a reduction in CREB expression/phosphorylation were found in the hippocampi of chronically treated mice. Our findings demonstrate for the first time significant structural and molecular changes in the adult hippocampus after prolonged paint thinner inhalation, indicating reduced hippocampal neuroplasticity and strongly supporting its implication in the behavioral dysfunctions associated to inhalant abuse.

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Ignitable liquids such as fuels, alcohols and thinners can be used in criminal activities, for instance arsons. Forensic experts require to know their chemical compositions, as well as to understand how different modification effects could impact them, in order to detect, classify and identify them properly in fire debris. The acid alteration/acidification of ignitable liquids is a modification effect that sharply alters the chemical composition, for example, of gasoline and diesel fuel, interfering in the forensic analysis and result interpretation. However, to date there is little information about the consequences of this effect over other accelerants of interests. In this research paper, the alteration by sulfuric acid of several commercial thinners and other accelerants of potential use in arsons is studied in-depth. For that purpose, spectral (by ATR-FTIR) and chromatographic (by GC-MS) data were obtained from neat and acidified samples. Then, the spectral and chromatographic modifications of each studied ignitable liquid were discussed, proposing several chemical mechanisms that explain the new by-products produced and the gradual disappearance of the initial compounds. Hydrolysis, Fischer esterification and alkylation reactions are involved in the modification of esters, alcohols, ketones and aromatic compounds of the studied ignitable liquids. This information could be crucial for correctly identifying these accelerants. Additionally, an exploratory analysis revealed that some of the most altered ignitable liquid samples might be very similar with each other, which could have impact on casework.

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BACKGROUND: Methemoglobin (MetHb) is an oxidized form of hemoglobin. It is a poor transporter of oxygen and is unable to deliver oxygen to the tissue. Globally, drug & toxin induced methemoglobinemia is more common as compared with the congenital form. Methemoglobinemia caused by paint thinner intoxication is rare. Methylene blue is well established as the first-line therapy for severe methemoglobinemia. CASE REPORT: A 25-year old man was brought to the Emergency Department after accidental consumption of paint thinner. On clinical examination, he had cyanosis and there were discrepancies in his pulse oximetry and arterial blood gas (ABG) analysis results. With this clue and supporting laboratory investigations, the diagnosis of toxin-induced methemoglobinemia was made. Due to the unavailability of methylene blue, alternative treatment with high-dose vitamin C was attempted, to which the patient responded. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The role of vitamin C in the treatment of methemoglobinemia has not been well established, with only a few published case reports. This patient had severe methemoglobinemia, with MetHb of 46.4%, which responded dramatically to vitamin C therapy, with no side effects. This case shows that high-dose vitamin C is safe and has the potential to be an effective alternative for the treatment of severe methemoglobinemia. In the presence of cyanosis, mismatch of pulse-oximetry and ABG-analysis are the key for the physician to suspect methemoglobinemia.

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In this paper, recent studies of backscattered acoustic signals in thinner steel-polymer tubing structures have been presented. Reassigned smoothed pseudo Wigner-Ville (rspWV) analysis has been adopted in order to diminish the cross-term effect, and achieve high resolution spectral. Vibration modes, which are associated to the resonances of circumferential waves, have been determined by using the modal isolation plan representation. At normalized frequencies below 140, an appreciable influence from the polymer coating thickness on the A0+ and S0 modes has been noticed. Furthermore, the trajectory of the A0- wave has been modified in the normalized frequency band 40-42. Group velocity curves of the A0- wave have, then, been graphically illustrated. The findings have shown a particular curvature change at reduced frequency 41 in the case of an immersed two-layer tube in water. Studies of acoustic backscattering involving steel-polymer tubing structures have confirmed the significant coupling of A0+ and S0 waves. Besides, the disappearance of the A0+ resonance trajectory has been observed; which is a very important phenomenon to understand.