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1.
Article in English | MEDLINE | ID: mdl-38827063

ABSTRACT

Large Language Models (LLMs) have demonstrated immense potential in artificial intelligence across various domains, including healthcare. However, their efficacy is hindered by the need for high-quality labeled data, which is often expensive and time-consuming to create, particularly in low-resource domains like healthcare. To address these challenges, we propose a crowdsourcing (CS) framework enriched with quality control measures at the pre-, real-time-, and post-data gathering stages. Our study evaluated the effectiveness of enhancing data quality through its impact on LLMs (Bio-BERT) for predicting autism-related symptoms. The results show that real-time quality control improves data quality by 19% compared to pre-quality control. Fine-tuning Bio-BERT using crowdsourced data generally increased recall compared to the Bio-BERT baseline but lowered precision. Our findings highlighted the potential of crowdsourcing and quality control in resource-constrained environments and offered insights into optimizing healthcare LLMs for informed decision-making and improved patient care.

2.
Article in English | MEDLINE | ID: mdl-38827111

ABSTRACT

Health literacy is crucial to supporting good health and is a major national goal. Audio delivery of information is becoming more popular for informing oneself. In this study, we evaluate the effect of audio enhancements in the form of information emphasis and pauses with health texts of varying difficulty and we measure health information comprehension and retention. We produced audio snippets from difficult and easy text and conducted the study on Amazon Mechanical Turk (AMT). Our findings suggest that emphasis matters for both information comprehension and retention. When there is no added pause, emphasizing significant information can lower the perceived difficulty for difficult and easy texts. Comprehension is higher (54%) with correctly placed emphasis for the difficult texts compared to not adding emphasis (50%). Adding a pause lowers perceived difficulty and can improve retention but adversely affects information comprehension.

3.
Procedia Comput Sci ; 219: 1509-1517, 2023.
Article in English | MEDLINE | ID: mdl-37205132

ABSTRACT

Health literacy is the ability to understand, process, and obtain health information and make suitable decisions about health care [3]. Traditionally, text has been the main medium for delivering health information. However, virtual assistants are gaining popularity in this digital era; and people increasingly rely on audio and smart speakers for health information. We aim to identify audio/text features that contribute to the difficulty of the information delivered over audio. We are creating a health-related audio corpus. We selected text snippets and calculated seven text features. Then, we converted the text snippets to audio snippets. In a pilot study with Amazon Mechanical Turk (AMT) workers, we measured the perceived and actual difficulty of the audio using the response of multiple choice and free recall questions. We collected demographic information as well as bias about doctors' gender, task preference, and health information preference. Thirteen workers completed thirty audio snippets and related questions. We found a strong correlation between text features lexical chain, and the dependent variables, and multiple choice response, percentage of matching word, percentage of similar word, cosine similarity, and time taken (in seconds). In addition, doctors were generally perceived to be more competent than warm. How warm workers perceive male doctors correlated significantly with perceived difficulty.

4.
Sensors (Basel) ; 23(2)2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36679432

ABSTRACT

The need to reduce greenhouse gas emissions from power generation has led to more and more installation of renewable energies such as wind and solar power. However, the high intermittency of these generators poses a threat to electrical grid stability. The power output of solar photovoltaic (PV) installations, for instance, depends on the solar irradiance, and consequently on weather conditions. In order to mitigate the adverse effects of solar intermittency, storage such as batteries can be deployed. However, the cost of a stationary energy storage system (SESS) is high, particularly for large PV installations. Battery electric vehicles (BEVs) are an alternative to SESS. With increasing number of BEVs, more and more storage capacity becomes available while these vehicles are charging. In this paper, we compare stationary batteries to mobile batteries of battery electric buses (BEBs) in a public bus terminus for balancing fluctuations of solar PV installations. Public buses have been chosen due to their large batteries and because they are more easily manageable than private cars. An optimisation model has been developed considering both the bus operator's and the PV operator's objectives. Cycle ageing of batteries is included in the investigation. Our analysis reveals that utilising public BEBs with high battery capacity to balance solar PV fluctuations can present a positive financial case.


Subject(s)
Electricity , Solar Energy , Renewable Energy , Wind , Motor Vehicles
5.
Ultrasonics ; 127: 106834, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36103756

ABSTRACT

A point contact/Coulomb coupling technique is generally used for visualizing the ultrasonic waves in Lead Zirconate Titanate (PZT) ceramics. The point contact and delta pulse excitation produce a broadband frequency spectrum and wide directional wave vector. In ultrasonic, the signal is corrupted with several types of noises such as speckle, Gaussian, Poisson, and salt and pepper noise. Consequently, the resolution and quality of the images are degraded. The reliability of the health assessment of any civil or mechanical structures highly depends on the ultrasonic signals acquired from the sensors. Recently, deep learning (DL) has been implemented for the reduction of noises from the signals and in images. Here, we have implemented deep learning-based convolutional autoencoders for suitable noise modeling and subsequently denoising the ultrasonic images. Two different metrics, PSNR and SSIM are calculated for quantitative analysis of ultrasonic images. PSNR provides higher visual interpretation, whereas the SSIM can be used to measure much finer similarities. Based upon these parameters speckle-noise demonstrated better than other noise models.


Subject(s)
Machine Learning , Ultrasonics , Reproducibility of Results , Signal-To-Noise Ratio
6.
Agri ; 34(3): 210-212, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35792699

ABSTRACT

Peripheral neuropathy secondary to entrapment of the nerves is not an uncommon etiology. Nerve entrapment is a common occurrence following trauma or surgery and poses significant diagnostic challenge. Entrapment neuropathy (EN) may not respond to standard neuropathic medication and may need invasive treatment. Pulsed radiofrequency (PRF) application is a recent modality and is gaining popularity for many EN as it does not cause neural ablation unlike conventional radiofrequency ablation. In this report, we present a case of young patient who presented with severe lower lateral leg pain in whom superficial peroneal nerve (SPN) EN was suspected and diagnostic SPN injection under ultrasound guidance confirmed the diagnosis. He subsequently underwent PRF neuromodulation and experienced long-lasting pain relief.


Subject(s)
Peroneal Neuropathies , Pulsed Radiofrequency Treatment , Humans , Male , Pain/etiology , Peroneal Neuropathies/diagnosis , Peroneal Neuropathies/etiology , Peroneal Neuropathies/therapy , Pulsed Radiofrequency Treatment/adverse effects , Ultrasonography
7.
J Multidiscip Healthc ; 14: 2429-2436, 2021.
Article in English | MEDLINE | ID: mdl-34511926

ABSTRACT

PURPOSE: The world is heavily suffering from the COVID-19 pandemic for more than a year, with over 191 million confirmed cases and more than 4.1 million deaths to date. Previous studies have explored several risk factors for coronavirus disease 2019 (COVID-19), but there is still a lack of association with ABO blood type. This study aimed to find out the relationship between the ABO blood group and COVID-19 outcomes in Bangladesh. SUBJECTS AND METHODS: This retrospective cross-sectional study was conducted in the intensive care unit (ICU) of a tertiary-level COVID-dedicated hospital in Dhaka city, Bangladesh, between April 2020 and November 2020. Records from 771 critically ill patients were extracted who were confirmed for COVID-19 by reverse transcriptase-polymerase chain reaction (RT-PCR) assay, and blood grouping records were available in the health records. RESULTS: The blood groups were 37.35%, 17.38%, 26.46%, and 18.81% for A, B, AB, and O type, respectively. Clinical symptoms were significantly more common in patients with blood type A (p < 0.05). Patients with blood type A had higher WBC counts and peak serum ferritin levels and both were statistically significant (p < 0.001). Patients with blood type A had a greater need for supplemental oxygen, and they were more likely to die in comparison to the patients with other blood types (p < 0.05). In multivariable analysis, our primary outcome death was significantly associated with blood type A (AOR: 3.49, 95% CI: 1.57-7.73) while adjusting for age, male gender, and non-communicable diseases. CONCLUSION: Based on this study results, it can be concluded that the COVID-19 patients with blood type A have a higher chance of death and other complications. The authors recommend blood grouping before treating the COVID-19 patients, and healthcare workers should prioritize treating the patients based on that result.

8.
Antioxidants (Basel) ; 9(11)2020 Nov 09.
Article in English | MEDLINE | ID: mdl-33182315

ABSTRACT

The antioxidant effects of the ethyl acetate fraction of Dillenia indica bark (DIBEt) and the underlying mechanisms were investigated in tert-butyl hydroperoxide (t-BHP)-stimulated oxidative stress in RAW 264.7 cells. Paper spray ionization-mass spectroscopy with positive-ion mode tentatively revealed 27 secondary metabolites in D. indica bark extract; predominant among them were alkaloids, phenolic acids, and flavonoids. A new triterpenoid (nutriacholic acid) was confirmed in DIBEt for the first time. DIBEt had strong free radical-scavenging capabilities and was also able to reduce t-BHP-induced cellular reactive oxygen species (ROS) generation in RAW 264.7 cells. DIBEt was found to prevent oxidative stress by boosting the levels of heme oxygenase-1 (HO-1) through the up-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) via the regulation of extracellular signal-regulated kinase (ERK) phosphorylation in RAW 264.7 cells. These results support the potential of DIBEt for defense against oxidative stress-stimulated diseases.

9.
Indian J Palliat Care ; 26(2): 164-172, 2020.
Article in English | MEDLINE | ID: mdl-32874029

ABSTRACT

The Indian Society for Study of Pain (ISSP), Cancer Pain Special Interest Group (SIG) guidelines, for the diagnosis and assessment of cancer pain in adults provide a structured, step-wise approach which will help to improve the management of cancer pain and to provide the patients with a minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs of patient population and situations in India. A questionnaire based on the key elements of each sub draft addressing certain inconclusive areas where evidence was lacking, was made available on the ISSP website and circulated by E-mail to all the ISSP and Indian Association of Palliative Care (IAPC) members. We recommend that a comprehensive pain assessment of all the patients should be conducted before initiating treatment. The patients should be educated about all the available pain control interventions. For assessing cancer pain, unidimensional tools such as Numeric Rating Scale, Visual Analog Scale, and Visual Rating Scale should always be used routinely. Patients with cancer pain should routinely be screened for distress and other psychological disorders, using the Patient Health Questionnaire-9. The most reliable assessment of pain is patients' self-reporting.

10.
Indian J Palliat Care ; 26(2): 180-190, 2020.
Article in English | MEDLINE | ID: mdl-32874031

ABSTRACT

The Indian Society for Study of Pain (ISSP), Cancer Pain Special Interest Group (SIG) guidelines on pharmacological management of cancer pain in adults provide a structured, stepwise approach, which will help to improve the management of cancer pain and to provide the patients with a minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs, patient population, and situations in India. A questionnaire, based on the key elements of each sub draft addressing certain inconclusive areas where evidence was lacking, was made available on the ISSP website and circulated by e-mail to all the ISSP and Indian Association of Palliative Care members. We recommend that analgesics for cancer pain management should follow the World Health Organization 3-step analgesic ladder appropriate for the severity of pain. The use of paracetamol and nonsteroidal anti-inflammatory drugs alone or in combination with opioids for mild-to-moderate pain should be used. For mild-to-moderate pain, weak opioids such as tramadol, tapentadol, and codeine can be given in combination with nonopioid analgesics. We recommend morphine as the opioid of the first choice for moderate-to-severe cancer pain. Sustained-release formulations can be started 12 hourly, once the effective 24 h dose with immediate-release morphine is established. Opioid switch or rotation should be considered if there is inadequate analgesia or intolerable side effects. For opioid-induced respiratory depression, µ receptor antagonists (e.g. naloxone) must be used promptly. Antidepressants and/or anticonvulsants should be used to treat neuropathic cancer pain, and the dose should be titrated according to the clinical response and side effects. External beam radiotherapy should be offered to all patients with painful metastatic bone pain. There is evidence on use of ketamine in cancer neuropathic pain, but with no beneficial effect, thus, it is not recommended.

11.
Indian J Palliat Care ; 26(2): 198-202, 2020.
Article in English | MEDLINE | ID: mdl-32874033

ABSTRACT

The Indian Society for Study of Pain (ISSP), cancer pain Special Interest Group (SIG) guidelines on complementary therapies for cancer pain in adults provides a structured, stepwise approach which will help to improve the management of cancer pain and to provide the patients with a minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs, patient population, and situations in India. A questionnaire based on the key elements of each sub drafts addressing certain inconclusive areas where evidence was lacking, was made available on the ISSP website and circulated by e-mail to all the ISSP and Indian Association of Palliative Care members. We recommend that psychological interventions, including psychoeducation, are useful and should be considered in patients with cancer pain and psychological distress. Furthermore, physical and complementary treatment can be used as an adjunctive therapy for patients with cancer pain.

12.
Indian J Palliat Care ; 26(2): 191-197, 2020.
Article in English | MEDLINE | ID: mdl-32874032

ABSTRACT

The Indian Society for Study of Pain (ISSP), Cancer Pain Special Interest Group, guidelines on pharmacological management of cancer pain in adults provide a structured, step-wise approach which will help to improve the management of cancer pain and to provide patients with a minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs, patient population, and situations in India. A questionnaire based on the key elements of each sub draft addressing certain inconclusive areas where evidence was lacking, was made available on the ISSP website and circulated by E-mail to all the ISSP and Indian Association of Palliative Care members. Antidepressants and/or anticonvulsants should be used to treat neuropathic cancer pain and the dose should be titrated according to the clinical response and side effects. External beam radiotherapy should be offered to all patients with painful metastatic bone pain. There is evidence on the use of ketamine in cancer neuropathic pain, but with no beneficial effect, thus it is not recommended.

13.
Indian J Palliat Care ; 26(2): 210-214, 2020.
Article in English | MEDLINE | ID: mdl-32874035

ABSTRACT

The Indian Society for Study of Pain (ISSP), Cancer Pain Special Interest Group guidelines on palliative care aspects in cancer pain in adults provide a structured, stepwise approach which will help to improve the management of cancer pain and to provide the patients with a minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs, patient population, and situations in India. A questionnaire based on the key elements of each sub draft addressing certain inconclusive areas where evidence was lacking was made available on the ISSP website and circulated by E-mail to all the ISSP and Indian Association of Palliative Care (IAPC) members. In a cancer care setting, approaches toward managing pain vary between ambulatory setting, home care setting, acute inpatient setting, and end-of-life care in hospice setting. We aim to expound the cancer pain management approaches in these settings. In an ambulatory palliative care setting, the WHO analgesic step ladder is used for cancer pain management. The patients with cancer pain require admission for acute inpatient palliative care unit for poorly controlled pain in ambulatory and home care settings, rapid opioid titration, titration of difficult drugs such as methadone, acute pain crisis, pain neuromodulation, and pain interventions. In a palliative home care setting, the cancer pain is usually assessed and managed by nurses and primary physicians with a limited input from the specialist physicians. In patients with cancer at the end of life, the pain should be assessed at least once a day. Moreover, physicians should be trained in assessing patients with pain who are unable to verbalize or have cognitive impairment.

14.
Indian J Palliat Care ; 26(2): 173-179, 2020.
Article in English | MEDLINE | ID: mdl-32874030

ABSTRACT

The Indian Society for Study of Pain (ISSP), Cancer Pain Special Interest Group guidelines on pharmacological management of cancer pain in adults provides a structured, step-wise approach which will help to improve the management of cancer pain and to provide the patients with a minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs, patient population, and situations in India. A questionnaire based on the key elements of each sub drafts addressing certain inconclusive areas where evidence was lacking, was made available on the ISSP website, and circulated by E-mail to all the ISSP and Indian Association of Palliative Care (IAPC) members. We recommend that analgesics for cancer pain management should follow the World Health Organization three-step analgesic ladder appropriate for the severity of pain. The use of paracetamol and nonsteroidal anti-inflammatory drugs alone or in combination with opioids for mild-to-moderate pain should be used. For mild-to-moderate pain, weak opioids such as tramadol, tapentadol, and codeine can be given in combination with nonopioid analgesics. We recommend morphine as the opioid of first choice for moderate-to-severe cancer pain.

15.
Indian J Palliat Care ; 26(2): 203-209, 2020.
Article in English | MEDLINE | ID: mdl-32874034

ABSTRACT

The Indian Society for Study of Pain (ISSP), Cancer Pain Special Interest Group guidelines on interventional management for cancer pain in adults provide a structured, stepwise approach which will help to improve the management of cancer pain and to provide the patients with minimally acceptable quality of life. The guidelines have been developed based on the available literature and evidence, to suit the needs, patient population, and situations in India. A questionnaire based on the key elements of each sub draft addressing certain inconclusive areas where evidence was lacking was made available on the ISSP website and circulated by e-mail to all the ISSP and Indian Association of Palliative Care members. We recommend using interventional management when conventional therapy fails to offer adequate benefits or causes undesirable side effects. Vertebroplasty should be offered to patients with uncontrolled bone pain when expertise is available.

16.
Food Chem ; 332: 127377, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32619942

ABSTRACT

In this study, paper spray ionization (PSI) coupled to high-resolution mass spectrometry has been used to identify secondary metabolites from ethanol extracts of Averrhoa carambola L. bark (ABE). Various phytoconstituents including phenolic acids, flavonoids, xanthones and terpenoids were identified from the bark. ABE shows potential antioxidant activity as well as markedly inhibited α-glucosidase, elastase, and tyrosinase enzyme activities in a concentration-dependent fashion, respectively. ABE significantly inhibited α-glucosidase at lower concentration (IC50: 7.15 ± 0.06 µg/mL). Identified compounds were tested to understand the biological activity of ABE. Experimental results suggest that norathyriol, one of the identified compounds, has significant α-glucosidase (IC50: 0.81 ± 0.01 µg/mL) inhibition and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities (IC50: 4.90 ± 0.09 µg/mL). At a dose of 100 mg/kg, ABE significantly decreased the postprandial blood glucose level in oral glucose tolerance test (OGTT). This study shows that carambola bark can be a potential source of bioactive compounds.


Subject(s)
Antioxidants/metabolism , Averrhoa/metabolism , Mass Spectrometry , Metabolomics/methods , Monophenol Monooxygenase/metabolism , Pancreatic Elastase/metabolism , alpha-Glucosidases/metabolism
17.
J Nutr Sci ; 9: e14, 2020 04 02.
Article in English | MEDLINE | ID: mdl-32284862

ABSTRACT

A low intake of fruit and vegetables is a significant contributor to the global burden of disease. The aim of this study was to estimate the size of the risk of type 2 diabetes (T2D) of a low intake and to investigate possible sex differences. In this regard, this study used a longitudinal data from the Stockholm Public Health Cohort located in Sweden, collected in 2010 and 2014. The analysis included 14 718 men and 20 589 women aged 25 to 84 years. Fruit and vegetable intake, separately <2 servings/d or combined <4 servings/d (one serving corresponding to 100 g) was set as a cut-point for low intake. The sex difference at baseline was examined. Sex-stratified logistic regression was performed with onset of T2D as the outcome and fruit and vegetable intake at baseline as the exposure with adjustment for other known risk factors. Results indicate that men consumed significantly (P < 0⋅001) less fruit and vegetables compared with women. A 62 % higher risk to develop T2D over the 4-year period was observed in men who had low vegetable intake compared with high intake after adjusting for age, education, BMI, smoking, alcohol and physical activity (OR 1⋅62; 95 % CI 1⋅00, 2⋅63). In women, a significantly higher risk of T2D was also observed with a low intake of vegetables, but not after adjustment. The present study suggests that higher consumption of vegetables seems to be protective for the onset of T2D in men. Thus, increasing the intake of vegetables in men should be a public health priority.


Subject(s)
Diabetes Mellitus, Type 2 , Diet , Eating , Feeding Behavior , Fruit , Vegetables , Adult , Age Factors , Aged , Aged, 80 and over , Chronic Disease , Cohort Studies , Female , Humans , Longitudinal Studies , Male , Middle Aged , Public Health , Risk Factors , Sex Factors , Smoking , Surveys and Questionnaires , Sweden
18.
Sci Total Environ ; 722: 137681, 2020 Jun 20.
Article in English | MEDLINE | ID: mdl-32208237

ABSTRACT

Fluorine is a chemical element which is often present in natural environment. According to the World Health Organization (WHO) standards fluoride content in drinking water cannot be higher than 1.5 mg F-/L. Nitrate was also found in many regions in the world. According to guidelines its content in drinking water cannot exceed 50 mg NO3-/L. Ingestion of fluoride and nitrate in excess leads to various health issues. There are many methods of fluoride removal, e.g. reverse osmosis, ion exchange or electrodialysis (ED). The aim of the research was to evaluate the influence of nitrate on fluoride separation by electrodialysis with monovalent selective ion-exchange membranes (PC-MVA and PC-MVK). During experiments the laboratory installation PCCell BED-1-System was applied. The ED tests were conducted at constant current density (0.78, 1.72, and 2.34 mA/cm2). Model solutions containing fluoride (5, 10, 15 mg F-/L), nitrate (15, 30, 45 mg NO3-/L) and sodium chloride (0.5 g NaCl/L) were applied. The obtained results showed that the ED process with monovalent selective ion-exchange membranes allowed to decrease fluoride content in product water below the WHO guidelines. It was observed that competition between nitrate and fluoride ions occurred during their transport through the anion-exchange membranes. The energy demand was dependent on the current density as well as on the salt concentration in treated solutions.


Subject(s)
Fluorides/isolation & purification , Filtration , Ion Exchange , Wastewater , Water Purification
19.
Life Sci ; 240: 117104, 2020 Jan 01.
Article in English | MEDLINE | ID: mdl-31783054

ABSTRACT

Xanthophylls constitute a major part of carotenoids in nature. They are an oxidized version of carotenoid. Xanthophyll has widely drawn scientists' attentions in terms of its functionality, bioavailability and diversity. An assortment of xanthophyll varieties includes lutein, zeaxanthin, ß-cryptoxanthin, capsanthin, astaxanthin, and fucoxanthin. Chemically, lutein and zeaxanthin are dipolar carotenoids with hydroxyl groups at both ends of their molecules that bestow hydrophilic properties to them. Hydrophilic affinity in lutein and zeaxanthin makes better bioavailability in reaction with singlet oxygen in water phase, whereas non-polar carotenoids have shown to have less efficiency in scavenging free radicals. Xanthophylls have been studied for their effects in a wide variety of diseases including neurologic, ophthalmologic, oral, allergic and immune diseases. This review highlights pharmaco-pharmaceutical applications of xanthophylls as well asits drug interactions with beta-carotene. Different types of xanthophylls have been shown to have neuroprotective effects. Fucoxanthin demonstrated potent antiplasmodial activity. Lutein and zeaxanthin prevent the progression of age related macular degeneration. They have also demonstrated promising effects on uveitis, retinitis pigmentosa, scleritis, cataracts, glaucoma, retinal ischemia and choroideremia. Astaxanthin showed to have skin protecting effects against ultraviolet light injury. Astaxanthin have anti-allergic activity against the contact dermatitis especially to treat the patients having adverse reactions induced by steroids. Astaxanthin has been reported to exert beneficial effects in preventing oral lichen planus and early stage cancers. ß-cryptoxanthin has been considered a good candidate for prevention of bone loss via osteoblastic bone formation and inhibiting osteoclastic bone resorption. There is also some concern that higher dose of xanthophylls may be linked to increased risk of skin cancer and gastric adenocarcinoma. However this increased risk was not statistically significant when adjusted for confounding factors. Further researches including clinical studies are needed to better evaluate the efficacy and safety of xanthophylls in prevention and treatment of different diseases.


Subject(s)
Xanthophylls/pharmacology , Xanthophylls/therapeutic use , Animals , Humans , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Primary Prevention
20.
Rapid Commun Mass Spectrom ; 33(7): 650-656, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30710409

ABSTRACT

RATIONALE: Molecular dynamics (MD) simulations with finite temperature were performed to improve the theoretical prediction of collisional cross section (CCS) values, especially for aromatic compounds containing long alkyl chains. METHODS: In this study, the CCS values of 11 aromatic compounds with long alkyl chains were calculated by MD simulations while considering internal energy at 300, 500, and 700 K, and the results were compared with experimentally determined values. RESULTS: The CCS values calculated at higher energies showed better agreement with the experimental values. Polycyclic aromatic hydrocarbons (PAHs) such as pentacene and benz[b]anthracene were also investigated, and better agreement between the theoretical and experimental results was observed when higher temperature (or higher internal energy) was considered. CONCLUSIONS: The data presented in this study show that the internal degrees of freedom of ions must be considered to accurately predict the CCS values of aromatic compounds with a flexible structure measured by ion mobility mass spectrometry.

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