The problem of identification an unknown substance by the radiographic method

This paper considers the problem of partial identification of the chemical composition of an unknown medium by the multiple X-ray of this medium. A sample of an unknown substance is assumed to be homogeneous in its chemical composition, and the photon flux, collimated both in direction and in energy. A mathematical model for the identification problem is formulated. The approach proposed to solving the problem is based on the method of singular value decomposition of a matrix. At the first stage of the solution the problem is reduced to finding singular numbers and singular vectors for the series systems of algebraic equations linear with respect to products of unknown quantities. Then, based on the data obtained, a special function is built, called an indicator to the distinguishability of substances, which enables the sufficient conditions for the distinguishability of various substances. Based on the tabular data, calculations were made for a number of specific groups of chemical elements.

Detection of Raspberry Ketone after Percutaneous Absorption of Rhododendrol-Containing Cosmetics and Its Mechanism of Formation

Here, we aimed to elucidate the mechanism of rhododendrol (RD)-induced leukoderma. We investigated the skin permeability of RD in an aqueous solution and in different cosmetic formulations (lotion and emulsion) in an in vitro skin permeation study. The samples were analyzed using high-performance liquid chromatography (HPLC), and an unknown substance appeared on the spectrum. For identification, we analyzed various possible substances, such as raspberry ketone (RK) and rhododendrol quinone, using HPLC and then compared the detected absorption spectra and further verified the matched components using liquid chromatography–mass spectrometry. The unknown substance was found to be RK. To clarify the mechanism of formation of RK, we conducted a 24-hour skin permeation test on heat-treated skin. By quantifying the RK in the samples using HPLC, we observed that an enzyme in the skin seemed to be the cause of RK generation and that the components of the emulsion formulation could also be a cause. To investigate the enzyme, we reacted alcohol dehydrogenase with RD and observed that it was one of the converting enzymes. As RK has been reported to be a substance that causes leukoderma, the intraepidermal metabolism of RD to RK may be one of the mechanisms of susceptibility to leukoderma.

Gasping on Oxygen: A Case Report on Toxic Methemoglobinemia

We report the case of a 27-year-old male patient who presented with refractory hypoxemia following the alleged inhalation of an unknown substance. The patient appeared to show worsening cyanosis despite increment of supplemental oxygenation. A drawn sample of the patient’s blood appeared chocolate brown in color, and disparity was noted between the patient’s oxygen saturation (SaO2) in his blood against the pulse oximetry (SpO2) reading. A diagnosis of toxic methemoglobinemia was established following elevated levels of methemoglobin discovered in his blood. The patient was started on methylene blue and instantaneously recovered without any complications. Methemoglobinemia should be suspected in any patient with refractory cyanosis, and early recognition of this condition could be potentially lifesaving.

Identification of Anthocyanins and Their Fouling Mechanisms during Non-Thermal Nanofiltration of Blueberry Aqueous Extracts

Organic fouling in the nanofiltration (NF) process, which is a non-thermal technology to recover active components, is a critical problem limiting its applications. This study seeks to identify the anthocyanins on the NF membrane and explore their fouling mechanisms during concentration of blueberry extracts. Seven kinds of monomeric anthocyanins in foulants—delphinidin-3-O-galactoside, delphinidin-3-O-glucoside, delphinidin-3-O-arabinoside, cyanidin-3-O-galactoside, petunidin-3-O-galactoside, peonidin-3-O-glucoside, and malvidin-3-O-glucoside—were identified. Moreover, chalcone, myricetin derivative, and an unknown substance with [M+H]+ at m/z 261.1309, which is the fragment ion corresponding to the break of glycoside bond of anthocyanins, were obtained. Interactions between anthocyanins and membrane made from polyamide were principally governed by the CH-π and π-π stacking of aromatic rings, the establishment of hydrogen bonds, and electrostatic interaction. This study will be helpful to further control fouling and choice of cleaning agents in concentration of anthocyanins-rich extracts.

The prevalence of liquid chromatography-tandem mass spectrometry-confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa

Background Paediatric poisoning is a common presentation to emergency departments worldwide. There is a paucity of data on the role of liquid chromatography-tandem mass spectrometry (LC-MS/MS), in the management of paediatric poisoning in low-and middle-income countries (LMICs). In high-income countries, most studies are retrospective, and few include children.Objective The study describes the prevalence of liquid chromatography-tandem mass spectrometry confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa.Methods Children admitted with suspected poisoning between 1 January 2017 and 31 December 2017, were recruited. All patients had a urine and/or blood sample sent for LC-MS/MS toxicology. Data collected included demographic data, clinical features, investigations, management, outcome and social interventions. Results 152 children, with median age of 39 (IQR 25 -61) months were enrolled of which 128 (84%) were poisoning cases. Of the 128 poisoning cases, 88 (69%) presented with a history of ingesting a known substance, 16 (12%) an unknown substance and 24 (19%) were cases of occult poisoning. LC-MS/MS was able to identify a substance in 92% of the cases of occult poisoning. In those who had presented with a seemingly known substance, LC-MS/MS found a different substance in 15 cases. LC-MS/MS was also able to detect multiple drugs in 40 patients. Of the poisoning cases, six (5%) cases were attempted homicide cases and 5 (4%) cases were attempted suicide cases. No children died. Individualized social interventions were instituted in poisoning cases. Emergency placement safety reasons was required in 6 children. Conclusion When the limitations are known, LC-MS/MS is useful in identifying cases of occult poisoning, identifying patients who have ingested multiple substances and/or an unknown substance and when targeted towards child protection. As LC-MS/MS is an expensive test, it should be used judiciously in LMICs.

The prevalence of liquid chromatography-tandem mass spectrometry confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa

Background Paediatric poisoning is a common presentation to emergency departments worldwide. There is a paucity of data on the role of liquid chromatography-tandem mass spectrometry (LC-MS/MS), in the management of paediatric poisoning in low-and middle-income countries (LMICs). In high-income countries, most studies are retrospective, and few include children. Objective The study describes the prevalence of liquid chromatography-tandem mass spectrometry confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa. Methods Children admitted with suspected poisoning between 1 January 2017 and 31 December 2017, were recruited. All patients had a urine and/or blood sample sent for LC-MS/MS toxicology. Data collected included demographic data, clinical features, investigations, management, outcome and social interventions. Results One hundred fifty-two children, with median age of 39 (IQR 25–61) months were enrolled of which 128 (84%) were poisoning cases. Of the 128 poisoning cases, 88 (69%) presented with a history of ingesting a known substance, 16 (12%) an unknown substance and 24 (19%) were cases of occult poisoning. LC-MS/MS was able to identify a substance in 92% of the cases of occult poisoning. In those who had presented with a seemingly known substance, LC-MS/MS found a different substance in 15 cases. LC-MS/MS was also able to detect multiple drugs in 40 patients. Of the poisoning cases, six (5%) cases were attempted homicide cases and 5 (4%) cases were attempted suicide cases. No children died. Individualized social interventions were instituted in poisoning cases. Emergency placement safety reasons was required in 6 children. Conclusion When the limitations are known, LC-MS/MS is useful in identifying cases of occult poisoning, identifying patients who have ingested multiple substances and/or an unknown substance and when targeted towards child protection. As LC-MS/MS is an expensive test, it should be used judiciously in LMICs.

The prevalence of liquid chromatography-tandem mass spectrometry-confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa

BackgroundPaediatric poisoning is a common presentation to emergency departments worldwide. There is a paucity of data on the role of liquid chromatography-tandem mass spectrometry (LC-MS/MS), in the management of paediatric poisoning in low-and middle-income countries (LMICs). In high-income countries, most studies are retrospective, and few include children.ObjectiveThe study describes the prevalence of liquid chromatography-tandem mass spectrometry confirmed paediatric poisoning at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa.MethodsChildren admitted with suspected poisoning between 1 January 2017 and 31 December 2017, were recruited. All patients had a urine and/or blood sample sent for LC-MS/MS toxicology. Data collected included demographic data, clinical features, investigations, management, outcome and social interventions. Results152 children, with median age of 39 (IQR 25 -61) months were enrolled of which 128 (84%) were poisoning cases. Of the 128 poisoning cases, 88 (69%) presented with a history of ingesting a known substance, 16 (12%) an unknown substance and 24 (19%) were cases of occult poisoning. LC-MS/MS was able to identify a substance in 92% of the cases of occult poisoning. In those who had presented with a seemingly known substance, LC-MS/MS found a different substance in 15 cases. LC-MS/MS was also able to detect multiple drugs in 40 patients. Of the poisoning cases, six (5%) cases were attempted homicide cases and 5 (4%) cases were attempted suicide cases. No children died. Individualized social interventions were instituted in poisoning cases. Emergency placement safety reasons was required in 6 children. Conclusion When the limitations are known, LC-MS/MS is useful in identifying cases of occult poisoning; identifying patients who have ingested multiple substances and/or an unknown substance and when targeted towards child protection. As LC-MS/MS is an expensive test, it should be used judiciously in LMICs.

Нелинейно-регрессионный алгоритм обработки сигналов полупроводниковых химических сенсоров, обеспечивающий селективное детектирование примесей в искусственном воздухе

New method is developed for proceeding a conductance change response Δσ,μS of a temperature (T) modulated chemical sensor. The method provides reliable substance identification and measurement of its trace concentrations for such impurities in arti-ficial air as ammonia, acetone, hexane, propane, toluene, turpentine etc. Due to this method the response of the ΔσY for a substance Y in actual concentration C range is interpolated with a completely nonlinear regression via discriminant modelling func-tions Fi(z=103/T,Ai, bi,ci,..),i=1-4 or 5. For principal parameters the plots AiY(C) are built which compose the selectivity/gauge portrait of Y in the air. In case when the analogous parameters of unknown substance X fit this portrait the substance is iden-tified as Y. And the common abscissa of corresponding crossing points of AiX with the curves AiY(C) indicates the value of the X concentration in units been used for Y.

An Amputated Tongue—The Consequences of a Human Bite

Drug-related hospital admissions are common, and up to 25% of patients presenting to emergency departments with injuries test positive for alcohol and drug use. This case reports on a 55-year-old male who attended the emergency department (ED) at the Royal United Hospital, Bath, UK. He presented after sustaining significant soft tissue trauma to his tongue, following recreational drug use of an unknown substance. His injuries included the amputation and loss of the anterior third of his tongue, having suffered a bite from another individual. This unusual case describes the patient’s injuries and subsequent management, both in the emergency department and during follow-up. This case will be of benefit to clinicians from many disciplines including dentists, oral and maxillofacial surgeons, ENT surgeons and speech and language therapists.