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1.
Mar Pollut Bull ; 205: 116667, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38972216

RESUMO

Triclosan (TCS), an antibacterial biocide, pervades water and sediment matrices globally, posing a threat to aquatic life. In densely populated cities like Mumbai, rivers and coastal bodies demand baseline TCS data for ecotoxicological assessment due to the excessive use of personal care products comprising TCS. This pioneering study compares spatiotemporal TCS variations and risks in freshwater and marine ecosystems employing multivariate analysis of physicochemical parameters. Over five months (January to May 2022), Mithi River exhibited higher TCS concentrations (water: 1.68 µg/L, sediment: 3.19 µg/kg) than Versova Creek (water: 0.49 µg/L, sediment: 0.69 µg/kg). Principal component analysis revealed positive correlations between TCS and physicochemical parameters. High-risk quotients (>1) underscore TCS threats in both water bodies. This study furnishes crucial baseline data, emphasizing the need for effective treatment plans for TCS in effluent waters released into the adjacent aquatic systems.

2.
Lung India ; 41(4): 307-317, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38953196

RESUMO

INTRODUCTION: Pneumococcal diseases pose a significant public health concern in India, with substantial morbidity and mortality, with the elderly and those with coexisting medical conditions being most at risk. Pneumococcus was also seen to be one of the main reasons for co-infection, pneumonia and complications in COVID. Current guidelines recommend vaccination for specific adult populations, but there is a lack of uniformity and guidance on risk stratification, prioritisation and optimal timing. METHODS: Nation Against Pneumococcal Infections - Expert Panel Opinion (NAP-EXPO) is a panel convened to review and update recommendations for adult pneumococcal vaccination in India. The panel of 23 experts from various medical specialties engaged in discussions and evidence-based reviews, discussed appropriate age for vaccination, risk stratification for COPD and asthma patients, vaccination strategies for post-COVID patients, smokers and diabetics, as well as methods to improve vaccine awareness and uptake. OUTCOME: The NAP-EXPO recommends the following for adults: All healthy individuals 60 years of age and above should receive the pneumococcal vaccine; all COPD patients, regardless of severity, high-risk asthma patients, post-COVID cases with lung fibrosis or significant lung damage, should be vaccinated with the pneumococcal vaccine; all current smokers and passive smokers should be educated and offered the pneumococcal vaccine, regardless of their age or health condition; all diabetic individuals should receive the pneumococcal vaccine, irrespective of their diabetes control. Strategies to improve vaccine awareness and uptake should involve general practitioners (GPs), primary health physicians (PHPs) and physicians treating patients at high risk of pneumococcal disease. Advocacy campaigns should involve media, including social media platforms. CONCLUSION: These recommendations aim to enhance pneumococcal vaccination coverage among high-risk populations in India in order to ensure a reduction in the burden of pneumococcal diseases, in the post-COVID era. There is a need to create more evidence and data to support the recommendations that the vaccine will be useful to a wider range of populations, as suggested in our consensus.

3.
Cureus ; 16(5): e59736, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38841048

RESUMO

BACKGROUND: The decision and timing of surgical exploration of intestinal obstruction depend on the clinical findings and probable etiology of the symptoms. Patients with intestinal obstruction often have intra-abdominal hypertension (IAH), which is associated with a poor prognosis. PURPOSE OF THE STUDY: The purpose of the study is to evaluate the surgical outcomes in patients with intestinal obstruction in relation to intra-abdominal pressure (IAP). MATERIALS AND METHODS: The study was conducted on 50 patients with intestinal obstruction undergoing surgery. Preoperatively, IAP was measured in all the patients and was allocated into two groups based on the presence or absence of IAP. Patients were assessed for the postoperative length of hospital or ICU stay, surgical site infection, wound dehiscence, and recovery following surgery. RESULTS: The patients with preoperative IAH had significantly longer postoperative stays, with a median stay of eight days in these patients compared to four days in patients without IAH (p=0.009). A significantly higher number of patients (24%) had gangrenous changes on the bowel wall (p=0.042) and fascial dehiscence (p=0.018) in the group associated with raised IAP. A total of 75% of patients who required ventilator support belonged to the raised IAP group. The mean IAP in patients admitted to the ICU was significantly higher than in patients not admitted to the ICU (p=0.027). CONCLUSION: Preoperative IAH in intestinal obstruction is a significant factor in predicting the possibility of bowel ischemia with gangrene, perforation, intra-abdominal sepsis, surgical site infections, and prolonged hospital stay. Early surgical exploration and abdominal decompression must be considered in such cases.

4.
Chem Commun (Camb) ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940673

RESUMO

Utilizing a novel approach known as aptamer-assisted phage display (APD), we identified an anti-PD-L1 peptide, NV Pep, capable of simultaneous binding to PD-L1 alongside the DNA aptamer MJ5C. Combined inhibition using NV Pep and MJ5C demonstrated significant enhancement compared to individual ligands against the PD-1/PD-L1 interaction.

5.
World J Surg ; 48(7): 1626-1633, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801218

RESUMO

INTRODUCTION: Postoperative Ileus (POI) negatively impacts patient outcomes and increases healthcare costs. Transcutaneous electrical nerve stimulation (TENS) has been found to improve gastrointestinal (GI) motility following abdominal surgery. However, its effectiveness in this context is not well-established. This study was designed to evaluate the role of TENS on the recovery of GI motility after exploratory laparotomy. METHODS: Patients undergoing exploratory laparotomy were randomized in a 1:1 ratio into control (standard treatment alone) and experimental (standard treatment + TENS) arms. TENS was terminated after 6 days or after the passage of stool or stoma movement. The primary outcome was time for the first passage of stool/functioning stoma. Non-passage of stool or nonfunctioning stoma beyond 6 days was labeled as prolonged POI. Patients were monitored until discharge. RESULTS: Median (interquartile range) time to first passage of stool/functioning stoma was 82.6 (49-115) hours in the standard treatment group and 50 (22-70.6) hours in the TENS group [p < 0.001]. Prolonged POI was noted in 11 patients in the standard treatment group (35.5%) and one in the TENS group (3.2%) [p = 0.003]. Postoperative hospital stay was similar in the two groups. CONCLUSION: TENS resulted in early recovery of GI motility by shortening the duration of POI without any improvement in postoperative hospital stay. TRIAL REGISTRATION NUMBER: CTRI/2021/10/037054.


Assuntos
Motilidade Gastrointestinal , Íleus , Laparotomia , Complicações Pós-Operatórias , Recuperação de Função Fisiológica , Estimulação Elétrica Nervosa Transcutânea , Humanos , Estimulação Elétrica Nervosa Transcutânea/métodos , Feminino , Masculino , Motilidade Gastrointestinal/fisiologia , Pessoa de Meia-Idade , Laparotomia/efeitos adversos , Laparotomia/métodos , Idoso , Íleus/etiologia , Íleus/terapia , Resultado do Tratamento , Adulto
6.
Environ Pollut ; 351: 124108, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705448

RESUMO

Triclosan (TCS) is a biocide widely used in personal care and medicinal products. TCS persists in sediments and has been detected worldwide, making sediments a vital route of TCS exposure to aquatic organisms. This experiment explored the bioaccumulation and toxicological effects of TCS-contaminated sediment. The study revealed that the half-life of TCS in the sediment-water system was 21.52 days. Exposure of Clarias magur juveniles to 0.4 and 0.8 mg kg-1 TCS-spiked sediment resulted in high Biota-Sediment Accumulation Factor (BSAF) with the highest bioaccumulation in the liver (29.62-73.61 mg kg-1), followed by gill (9.22-17.57 mg kg-1), kidney (5.04-9.76 mg kg-1), muscle (2.63-4.87 mg kg-1) and brain (1.53-3.20 mg kg-1). Furthermore, a concentration-dependent increase in oxidative stress biomarkers such as superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) was documented during 45 days of exposure in gill, liver, kidney, muscle, and brain tissues of exposed fish. A similar increasing trend was also recorded for liver transaminase enzymes such as glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) during the experimental period compared to control. Serum biochemical analysis revealed a significant time and concentration-dependent increase in serum glucose, serum GOT, and serum GPT, while serum total protein and albumin decreased significantly during exposure. These findings demonstrate high bioaccumulative and toxic nature of TCS in fish, promoting multiple physiological and biochemical dysfunctions through sediment exposure. The study underscores the urgent need for strengthened regulations and robust monitoring of triclosan across various environmental matrices, including sediment, to mitigate the detrimental impacts of TCS effectively.


Assuntos
Biomarcadores , Peixes-Gato , Sedimentos Geológicos , Glutationa Transferase , Triclosan , Poluentes Químicos da Água , Triclosan/toxicidade , Triclosan/metabolismo , Animais , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo , Sedimentos Geológicos/química , Peixes-Gato/metabolismo , Biomarcadores/metabolismo , Glutationa Transferase/metabolismo , Brânquias/metabolismo , Brânquias/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Água Doce , Rim/metabolismo , Rim/efeitos dos fármacos , Monitoramento Ambiental/métodos
7.
Environ Toxicol Pharmacol ; 108: 104437, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38609060

RESUMO

Oxybenzone is an ultraviolet filter frequently used in Personal Care Products, plastics, furniture, etc. and is listed as an Emerging Contaminant. This report studied the acute toxicity of Oxybenzone to Lemna minor after exposure to graded concentrations of Oxybenzone for 7 days. IC50 for growth was found to be 8.53 mg L-1. The hormesis effect was reported at lower concentrations, while growth and pigments reduced from 2.5 to 12.5 mg L-1 in a concentration-related manner. The impact of Oxybenzone on protein and antioxidant enzymes- Catalase and Guaiacol Peroxidase revealed less stress up to 2.5 mg L-1 than control, increasing further from 5 to 10 mg L-1. Enzyme activity decreased over-time but always remained higher than control over a period of 7 days. Thus, our findings reveal that indiscriminate discharge of Oxybenzone could be potentially toxic to the aquatic primary producers at higher concentrations, causing an ecological imbalance in aquatic ecosystems.


Assuntos
Araceae , Benzofenonas , Catalase , Peroxidase , Poluentes Químicos da Água , Poluentes Químicos da Água/toxicidade , Benzofenonas/toxicidade , Catalase/metabolismo , Araceae/efeitos dos fármacos , Araceae/crescimento & desenvolvimento , Peroxidase/metabolismo , Testes de Toxicidade Aguda , Protetores Solares/toxicidade , Clorofila/metabolismo
8.
Heliyon ; 10(8): e29410, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644823

RESUMO

Currently, the Internet of Things (IoT) generates a huge amount of traffic data in communication and information technology. The diversification and integration of IoT applications and terminals make IoT vulnerable to intrusion attacks. Therefore, it is necessary to develop an efficient Intrusion Detection System (IDS) that guarantees the reliability, integrity, and security of IoT systems. The detection of intrusion is considered a challenging task because of inappropriate features existing in the input data and the slow training process. In order to address these issues, an effective meta heuristic based feature selection and deep learning techniques are developed for enhancing the IDS. The Osprey Optimization Algorithm (OOA) based feature selection is proposed for selecting the highly informative features from the input which leads to an effective differentiation among the normal and attack traffic of network. Moreover, the traditional sigmoid and tangent activation functions are replaced with the Exponential Linear Unit (ELU) activation function to propose the modified Bi-directional Long Short Term Memory (Bi-LSTM). The modified Bi-LSTM is used for classifying the types of intrusion attacks. The ELU activation function makes gradients extremely large during back-propagation and leads to faster learning. This research is analysed in three different datasets such as N-BaIoT, Canadian Institute for Cybersecurity Intrusion Detection Dataset 2017 (CICIDS-2017), and ToN-IoT datasets. The empirical investigation states that the proposed framework obtains impressive detection accuracy of 99.98 %, 99.97 % and 99.88 % on the N-BaIoT, CICIDS-2017, and ToN-IoT datasets, respectively. Compared to peer frameworks, this framework obtains high detection accuracy with better interpretability and reduced processing time.

9.
Blood ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669631

RESUMO

HLA-mismatched transplants with either in vitro depletion of CD3+TCRαß/CD19 (TCRαß) cells or in vivo T-cell depletion using post-transplant cyclophosphamide (PTCY) have been increasingly used for patients with inborn errors of immunity (IEI). We performed a retrospective multicenter study via the EBMT registry on 306 children with IEI undergoing first transplant between 2010-2019 from an HLA-mismatched donor using TCRαß (n=167) or PTCY (n=139). Median age at HSCT was 1.2 years (range, 0.03-19.6 years). The 3-year overall survival (OS) was 78% (95% confidence interval (CI), 71-84%) after TCRαß and 66% (57-74%) after PTCY (p=0.013). Pre-HSCT morbidity score (hazard ratio (HR) 2.27, 1.07-4.80, p=0.032) and non-Busulfan/Treosulfan conditioning (HR 3.12, 1.98-4.92, p<0.001) were the only independent predictors of unfavorable OS. The 3-year event-free survival (EFS) was 58% (50-66%) after TCRαß and 57% (48-66%) after PTCY (p=0.804). Cumulative incidence of severe acute GvHD was higher after PTCY (15%, 9-21%) than TCRαß (6%, 2-9%, p=0.007), with no difference in chronic GvHD (PTCY, 11%, 6-17%; TCRαß, 7%, 3-11%, p=0.173). The 3-year GvHD-free EFS was 53% (44-61%) after TCRαß and 41% (32-50%) after PTCY (p=0.080). PTCY had significantly higher rates of veno-occlusive disease (14.4% versus TCRαß 4.9%, p=0.009), acute kidney injury (12.7% versus 4.6%, p=0.032) and pulmonary complications (38.2% versus 24.1%, p=0.017). Adenoviraemia (18.3% versus PTCY 8.0%, p=0.015), primary graft failure (10%, versus 5%, p=0.048), and second HSCT (17.4% versus 7.9%, p=0.023) were significantly higher in TCRαß. In conclusion, this study demonstrates that both approaches are suitable options in IEI patients, although characterized by different advantages and outcomes.

10.
Org Lett ; 26(17): 3667-3672, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38656123

RESUMO

We disclose N'-arylidene-N-acryloyltosylhydrazides as novel skeletons for the synthesis of biologically relevant alkylated pyrazolones through a photoinduced radical cascade with N-(acyloxy)pthalimides as readily available alkyl surrogates. The reaction proceeds through the formation of a photoactivated electron donor-acceptor (EDA) complex between alkyl N-(acyloxy)phthalimide (NHPI) esters and LiI/PPh3 as a commercially available donor system. The reaction exhibits a broad scope and scalability, thereby enabling synthesis of a broad spectrum of functionally orchestrated alkylated pyrazolones under mild and transition-metal-free conditions.

11.
Indian J Anaesth ; 68(2): 189-195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38435662

RESUMO

Background and Aims: Adequate sedation is essential for children undergoing magnetic resonance imaging (MRI) console. Propofol is commonly used for sedation, but it has the drawback of upper airway collapse at higher doses, which may be overcome by ketamine. This study was designed to evaluate the beneficial effect of ketamine on propofol in preventing airway collapse. Methods: Fifty-eight children undergoing MRI were randomised to Group P (propofol bolus dose followed by infusion or Group KP (bolus dose of ketamine and propofol followed by propofol infusion). The primary aim is to compare the upper airway cross-sectional area (CSA) and diameters (transverse diameter [TD] and anteroposterior diameter [APD]) obtained from MRI during inspiration and expiration. Results: Upper airway collapse as measured by delta CSA in mean (SD) [95% confidence interval] was statistically more significant between the two groups [at the soft palate level, 16.9 mm2 (19.8) [9.3-24.4] versus 9.0 mm2 (5.50) [6.9-11.1] (P = 0.043); at the base of the tongue level, 15.4 mm2 (11.03) [11.2-19.6] versus 7.48 mm2 (4.83) [5.64-9.32] (P < 0.001); at the epiglottis level, 23.9 (26.05) [14.0-33.8] versus 10.9 mm2 (9.47) [7.35-14.5] (P = 0.014)]. A significant difference was obtained for TD at all levels and for APD at the soft palate and base of tongue level. Conclusion: Adding a single dose of ketamine to propofol reduced the upper airway collapse significantly, as evidenced by the MRI-based measurements of upper airway dimensions, compared to propofol alone.

13.
RSC Adv ; 14(9): 5817-5845, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38362068

RESUMO

The I2/DMSO pair has emerged as a versatile, efficient, practical, and eco-friendly catalyst system, playing a significant role as a mild oxidative system, and thus employed as a good alternative to metal catalysts in synthetic chemistry. Presently, I2/DMSO is a thriving catalytic system that is used in preparing C-C and C-X (X = O/S/N/Se/Cl/Br) bonds, resulting in the formation of various bioactive molecules. Many processes utilize this system, including in situ glyoxal synthesis by diverse sp, sp2, and sp3 functionalities via iodination and subsequent Kornblum oxidation. Focusing on oxidation processes, this study examines the synergistic effect of dimethyl sulfoxide (DMSO) and molecular iodine in improving synthetic techniques. We provide a comprehensive overview of the research progress on the I2/DMSO catalytic system for the formation of C-C and C-heteroatom bonds from 2018 to the present. Additionally, the future prospects of this research field are discussed.

14.
Org Lett ; 26(7): 1458-1462, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38345317

RESUMO

We describe a novel, regioselective alkylboration of versatile (hetero)benzylidenecyclopropanes with ß-H-containing alkyl iodides and bis(pinacolato)diboron enabled by copper catalysis. This three-component method allows for consecutive B-Csp3 and Csp3-Csp3 bond formation to access Csp3-enriched diverse tertiary cyclopropyl boronic esters with broad functionality tolerance, and the so-formed C-B bond is amenable to further structural diversification. Radical clock experiment, Hammett analysis, and DFT calculation suggest a mechanism of polar, rather than radical manifold, and SN2-type C-C bond formation was found to be the rate-limiting step instead of migratory alkene insertion.

15.
Biom J ; 66(1): e2300168, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38057145

RESUMO

Recently, there has been a growing interest in designing cluster trials using stepped wedge design (SWD). An SWD is a type of cluster-crossover design in which clusters of individuals are randomized unidirectional from a control to an intervention at certain time points. The intraclass correlation coefficient (ICC) that measures the dependency of subject within a cluster plays an important role in design and analysis of stepped wedge trials. In this paper, we discuss a Bayesian approach to address the dependency of SWD on the ICC and robust Bayesian SWDs are proposed. Bayesian design is shown to be more robust against the misspecification of the parameter values compared to the locally optimal design. Designs are obtained for the various choices of priors assigned to the ICC. A detailed sensitivity analysis is performed to assess the robustness of proposed optimal designs. The power superiority of Bayesian design against the commonly used balanced design is demonstrated numerically using hypothetical as well as real scenarios.


Assuntos
Projetos de Pesquisa , Humanos , Teorema de Bayes , Fatores de Tempo , Estudos Cross-Over , Análise por Conglomerados , Tamanho da Amostra
17.
JCO Glob Oncol ; 9: e2300047, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38085046

RESUMO

PURPOSE: The purpose of this study was to understand the impact of population diversity and geographic variation on tumor mutation burden (TMB) scores across cancers and its implication on stratification of patients for immune checkpoint inhibitor (ICI) therapy. MATERIALS AND METHODS: This retrospective study used whole-exome sequencing (WES) to profile 1,233 Indian patients with cancer across 30 different cancer types and to estimate their TMB scores. A WES-based pipeline was adopted, along with an indigenously developed strategy for arriving at true somatic mutations. A robust unsupervised machine learning approach was used to understand the distribution of TMB scores across different populations and within the population. RESULTS: The results of the study showed a biphasic distribution of TMB scores in most cancers, with different threshold scores across cancer types. Patients with cancer in India had higher TMB scores compared with the Caucasian patients. We also observed that the TMB score value at 90th percentile (predicting high efficacy to ICI) was high in four different cancer types (sarcoma, ovary, head and neck, and breast) in the Indian cohort as compared with The Cancer Genome Atlas or public cohort. However, in lung and colorectal cancers, the TMB score distribution was similar between the two population cohorts. CONCLUSION: The findings of this study indicate that it is crucial to benchmark both cancer-specific and population-specific TMB distributions to establish a TMB threshold for each cancer in various populations. Additional prospective studies on much larger population across different cancers are warranted to validate this observation to become the standard of care.


Assuntos
Exoma , Sarcoma , Feminino , Humanos , Exoma/genética , Estudos Retrospectivos , Estudos Prospectivos , Biomarcadores Tumorais/genética , Mutação
18.
Artigo em Inglês | MEDLINE | ID: mdl-37971584

RESUMO

In the present scenario, waste management, especially agro-waste, is one of the major challenges. India is an agrarian country and the economy depends on agriculture and a huge amount of agro-wastes are generated. In this study, biochar was prepared from paddy straw and sugarcane bagasse and was used in the feed of genetically improved farm tilapia (GIFT) at 0.5% (w/w) basis to study its effect on growth and haematological parameters. An experiment was carried out in triplicate in 500-l capacity FRP tanks comprising two treatments and one control. Tanks were filled with inland saline soil to maintain 25-cm soil's bed and water with 12 ppt salinity. A total of 22 fish having an average length of 5.14 ± 0.07 cm and weight of 4.8 ± 0.05 g were stocked in each tank; the fish were fed at apparent satiation level, twice daily for 45 days. It was observed that growth parameters like SGR% (specific growth rate), weight gain (WG%), and feed conversion ratio (FCR) were significantly improved (p < 0.05) than the control. Biochar-enriched feed also significantly improved the haematological parameters like red blood cell (RBC), white blood cell (WBC), haemoglobin (Hb) haematocrit % (HCT), mean cell haemoglobin concentration (MCH), and MCV (mean cell volume) in treatment groups than the control. Feeding biochar as feed additives was also found to decrease catalase (CAT) and enhanced amylase and lipase activities in treatments as compared to control (p < 0.05). It can be concluded that the application of biochar as a feed additive enhanced the growth and overall health of the fish, and it can enhance fish production. However, biochar from sugarcane bagasse was found to be more effective than the paddy straw biochar in the diet of tilapia (GIFT).

19.
Org Lett ; 25(46): 8290-8295, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37962249

RESUMO

We report a photoredox system comprising sodium iodide, triphenyl phosphine, and N,N,N',N'-tetramethylethylenediamine (TMEDA) that can form a self-assembled tetrameric electron donor-acceptor (EDA) complex with diaryliodonium reagents (DAIRs) and furnish aryl radicals upon visible light irradiation. This practical mode of activation of DAIRs enables arylation of an array of heterocycles under mild conditions to provide the respective heteroaryl-(hetero)aryl assembly in moderate to excellent yields. Detailed mechanistic investigations comprising photophysical and DFT studies provided insight into the reaction mechanism.

20.
Philos Trans A Math Phys Eng Sci ; 381(2263): 20220373, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-37926212

RESUMO

In this paper, we formulate a geometric nonlinear theory of the mechanics of accreting-ablating bodies. This is a generalization of the theory of accretion mechanics of Sozio & Yavari (Sozio & Yavari 2019 J. Nonlinear Sci. 29, 1813-1863 (doi:10.1007/s00332-019-09531-w)). More specifically, we are interested in large deformation analysis of bodies that undergo a continuous and simultaneous accretion and ablation on their boundaries while under external loads. In this formulation, the natural configuration of an accreting-ablating body is a time-dependent Riemannian [Formula: see text]-manifold with a metric that is an unknown a priori and is determined after solving the accretion-ablation initial-boundary-value problem. In addition to the time of attachment map, we introduce a time of detachment map that along with the time of attachment map, and the accretion and ablation velocities, describes the time-dependent reference configuration of the body. The kinematics, material manifold, material metric, constitutive equations and the balance laws are discussed in detail. As a concrete example and application of the geometric theory, we analyse a thick hollow circular cylinder made of an arbitrary incompressible isotropic material that is under a finite time-dependent extension while undergoing continuous ablation on its inner cylinder boundary and accretion on its outer cylinder boundary. The state of deformation and stress during the accretion-ablation process, and the residual stretch and stress after the completion of the accretion-ablation process, are computed. This article is part of the theme issue 'Foundational issues, analysis and geometry in continuum mechanics'.

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