Present Data Research Articles

Experimental and kinetic study of methanol/ethanol assisted oxidative degradation of ammonia in supercritical water

Ammonia is a refractory intermediate during supercritical water oxidation (SCWO) of nitrogen-containing wastes, and alcohols are usually introduced as auxiliary fuels to accelerate its degradation. The kinetics of methanol/ethanol assisted oxidative degradation of ammonia in supercritical water have been investigated in a flow reactor, covering alcohol-to-ammonia ratios of 0.2–2.0. During SCWO of ammonia-methanol mixtures, ammonia was mostly converted to N2, with N2O as the main by-product. Increasing methanol concentration facilitated effectively the degradation of ammonia. For the cases with ethanol assistance, high concentrations of HCN were detected at the investigated temperature. Increase in ethanol concentration enhanced ammonia conversion, but had a non-monotonic influence on N2 production. A detailed chemical kinetic model was developed by integrating the nitrogen chemistry with methanol/ethanol mechanisms. The model performance was further validated by comparing to the present and literature data. The model reproduced the ammonia conversions at different conditions fairly well, but overpredicted the N2 yield and underpredicted the NO2 and HCN yields slightly. Based on the model, reaction mechanism was inferred and important elementary steps were identified through kinetic analyses. Finally, the influence of process parameters on ammonia degradation rate was numerically explored. This study is expected to facilitate the application of SCWO technology for N-containing wastes treatment.

A-306 High Sensitivity Capability of an Anti-müllerian Hormone Assay on the Beckman Coulter DxI 9000 Immunoassay Analyzer*, a Next Step Toward Enabling Ovarian Failure Staging?

Abstract Background Measurement of anti-müllerian hormone (AMH) has proven value in the evaluation of ovarian reserve using assays such as the Beckman Coulter Access AMH assay. If improved sensitivity of AMH measurement can be achieved, enhanced clinical utility during the assessment of reproductive aging and ovarian response to enable staging of ovarian failure is possible (Practice Committee of the American Society of Reproductive Medicine 2020, Cappola et al. 2023). The Beckman Coulter DxI 9000 Immunoassay Analyzer* has been designed with new technology that can be leveraged to improve assay sensitivity. Such technological advancements include the new Lumi-Phos PRO chemiluminescent substrate which yields markedly increased signal-to-noise, a new luminometer with increased dynamic range, and improved low-volume pipetting capabilities. Data herein summarize results from analytical verification studies of the Access AMH assay on the DxI 9000 Immunoassay Analyzer. Results demonstrate an example of DxI 9000 technologies enabling sensitivity claims that are up to 20-fold improved. * The official name is DxI 9000 Access Immunoassay Analyzer. Methods A method comparison study was performed based on CLSI guideline EP09c, 3rd ed. to compare results for the Access AMH assay on DxI 9000 to the predicate device, the Access AMH assay on the Access 2 Immunoassay System. Within-laboratory precision was also evaluated following CLSI EP05-A3. Finally, performance at low analyte levels was evaluated following CLSI EP17-A2, and linearity was evaluated following CLSI EP06-Ed2. Results Method comparison of the Access AMH assay on DxI 9000 compared to the Access AMH assay on the Access 2 yielded excellent agreement with a Passing-Bablok slope of 1.02 for N=126 samples. Further, bias estimates for a number of key medical decision points suggest minimal bias (≤ 2%) across the assay range, and minimal non-linearity was observed. 20-day imprecision studies yielded CV’s between 2 and 5% across a broad range of concentrations evaluated. Sensitivity studies yielded estimates of limit of quantitation (LoQ) between 0.001 and 0.003 ng/mL. This represents an approximately 10- to 20-fold improvement in sensitivity claims compared to the AMH assay on the Access 2 and other commercially available automated immunoassay analyzers. Conclusions The data herein present performance data for the Access AMH assay on the DxI 9000 Immunoassay Analyzer. The assay demonstrates excellent accuracy relative to the predicate device, while showing good linearity and imprecision. Of note, the Access AMH assay exhibits exceptional low-end performance on the DxI 9000 analyzer as demonstrated by the ability to enable sensitivity claims that are up to 20-fold improved in comparison to existing immunoassays for the measurement of AMH. The sensitivity capabilities of the Access AMH assay on DxI 9000 suggest an opportunity for the addition of further intended uses for scenarios where extremely low AMH measurements can provide additional value of clinical significance. Further studies are needed to fully understand additional clinical utilities of the Access AMH assay with high sensitivity capability on DxI 9000, including the assessment of reproductive aging for menopause diagnosis or ovarian response for fertility treatment.

Educational practice in Germany between racism and far-right ideologies

Researching educational responses to far-right youth mobilization and ideologies has so far focused mainly on informal education spaces. We thus know little about how and why teachers seek to respond to these issues in their classrooms in formal education. This is despite the fact that far-right mobilization and attitudes are rising in Germany and are having a political impact. In this article I present data from an 18-month ethnographic study in Berlin’s secondary schools, arguing that it is not only important to understand how teachers conceptualize the problem in their student body but also how teachers seek to address these issues. Through this knowledge, we will be able to better understand and systematically respond to far-right ideologies in classrooms.

Experimental measurements and theoretical calculations of excitation functions of 103Rh(α,xn)106m,105g,104gAg and 103Rh(α,αxn)101m,102gRh reactions up to 40 MeV

Activation cross sections of 103Rh(α,xn)106m,105g,104gAg and 103Rh(α,αxn)101m,102gRh radionuclides were measured at energies ranging from their respective threshold energies up to 40 MeV. Standard stacked foil activation technique was employed for irradiation. Residual activity was assayed using high-resolution gamma-ray spectrometry. Excitation functions were also theoretically calculated using TALYS nuclear reaction model to reproduce the experimental cross section data. The present data are compared with the available literature data, TENDL-2023 data using default values as well as the theoretical data calculated by TALYS-1.96. The shape and amplitude of the experimentally obtained excitation functions were well reproduced theoretically for all the studied radionuclides except for 105gAg, for which magnitude of the cross sections was not reproduced. The integral yields were also deduced using the measured cross sections and the stopping power of natural Rh from 40 MeV down to their threshold energies for these radionuclides, and compared with the experimental yield data available in the literature.

Dual HER2 inhibition: Is two better than one?

Li etal. present data from a randomized frontline phase II trial in HER2+ gastroesophageal cancers exploring dual targeting of HER2 with HLX22 (a novel HER2-specific antibody) with HLX02 (a trastuzumab biosimilar) and capecitabine/oxaliplatin chemotherapy. While the objective response and progression-free survival are encouraging, the future development of the combination in a crowded HER2 space remains unclear.

Using artificial intelligence for bladder cancer detection during cystoscopy and its impact on clinical outcomes: a protocol for a systematic review and meta-analysis

IntroductionCystoscopy has revolutionised the process of diagnosing bladder cancer leading to better categorisation of risk levels and more precise treatment plans. Nonetheless, concerns arise about the lack of uniformity among...

Simplified inverse distance weighting-immersed boundary method for simulation of fluid-structure interaction

When simulating fluid-structure interaction (FSI) problems involving moving objects, the implicit inverse distance weighting-immersed boundary method (IDW-IBM) developed by Du et al. [1] has to construct a large square correlation matrix and solve its inversion at each time step. In this work, a simplified inverse distance weighting-immersed boundary method (SIDW-IBM) is proposed to eliminate the intrinsic limitations in the original implicit IDW-IBM. Through error analysis using Taylor series expansion, a second order approximation can be derived, which allows us to approximate the large square correlation matrix into a diagonal matrix; thereby, we proposed the SIDW-IBM based on this second order approximation to explicitly evaluate the velocity corrections, where the needs to assemble the large correlation matrix and inverse it are circumvented. Owing to the fact that the inverse distance weighting interpolation removes the limitations in the Dirac delta function, the proposed SIDW-IBM has been successfully implemented on the non-uniform meshes to further improve the computational efficiency. The proposed SIDW-IBM is integrated with the reconstructed lattice Boltzmann flux solver (RLBFS) [2] to simulate some classic incompressible viscous flows, including flow past an in-line oscillating cylinder, flow past a heaving airfoil, and flow past a three-dimensional flexible plate. The good agreement between the present results and reference data demonstrates the capability and feasibility of the SIDW-IBM for simulating FSI problems with moving boundaries and large deformations.

Onasemnogene abeparvovec gene therapy for spinal muscular atrophy: A cohort study from the United Arab Emirates.

Spinal muscular atrophy (SMA) manifests with progressive motor neuron degeneration, leading to muscle weakness. Onasemnogene abeparvovec is a US Food and Drug Administration-approved gene replacement therapy for SMA. This study aimed to present short-term data of children in the United Arab Emirates (UAE) treated with onasemnogene abeparvovec, particularly in the context of children requiring invasive ventilatory support via tracheostomy. A retrospective analysis was performed on 60 children who received onasemnogene abeparvovec. All these children received corticosteroids. They were followed up for up to 3 months. Motor function assessments were performed before and after the gene therapy. Comprehensive clinical evaluations, including pulmonary functions, were performed at baseline and the 3-month mark. Forty-three percent were male, and the mean age at the time of infusion was 29.6 months (SD ± 17.2). The mean weight was 10.1 kg (SD 2.6). All children demonstrated marked improvements in motor function within 3 months of gene therapy administration. No adverse effects attributable to corticosteroid therapy were observed. Positive clinical outcomes, including increased ventilator-free intervals, reduced antibiotic dependency, and fewer hospital admissions, were reported among children with invasive ventilation via tracheostomy. This study demonstrates the favorable tolerability and promising responses to onasemnogene abeparvovec in invasively ventilated pediatric patients. Early improvements in motor function, as observed within 3 months post-treatment, suggest its potential as a viable therapeutic option for this vulnerable patient population.

The puzzle of suppression of nuclear level density in N ≈ Z Zn isotopes compared to N > Z

A systematic investigation of isospin dependence of nuclear level density (NLD) is performed for the Zn isotopes. Experimental level densities of 67Zn and 61Zn have been determined by analyzing the spectra of evaporated neutrons emitted from the excited 68Zn and 62Zn nuclei populated via 4He + 64Ni and 4He + 58Ni reactions, respectively. At the low excitation energies, the neutron spectra are predominantly contributed by the first-chance decay, leading to 67Zn and 61Zn as daughters for the two cases. A comparison of the present experimental data along with previously measured NLDs of 66Zn, 64Zn, and 60Zn is performed with state-of-the-art microscopic calculations. While the experimental NLDs of stable isotopes (i.e., 67Zn, 66Zn, and 64Zn) align excellently with theoretical predictions, a compelling contrast emerges for the unstable isotopes 61Zn and 60Zn, exhibiting NLDs an order of magnitude lower than predicted. The possible origins of the observed suppression of NLDs for the N ≈ Z isotopes are discussed. A significant reduction of level density for nuclei situated away from the stability line could have critical implications for the calculation of astrophysical reaction rates pertinent to heavy-element nucleosynthesis.

Blue rubber bleb nevus syndrome: A European multicenter cohort study

Background and aimBlue Rubber Bleb Nevus Syndrome (BRBNS) is a rare congenital vascular entity, mainly characterized by cutaneous and gastrointestinal venous malformations. BRBNS remains relatively unexplored and only limited descriptive data is available. The aim of this study was to evaluate the clinical features, diagnostic work-up and therapeutic management in current practice. MethodsA multicenter, European, cohort study was performed to investigate the BRBNS population. Patient demographics, clinical presentation and management data were collected. ResultsIn this multicenter cohort study including 44 patients, BRBNS is diagnosed at a median age of 12 years, mainly based on clinical presentation (65.9 %). The majority of patients present cutaneous (68.2 %) and digestive (79.5 %) lesions, mainly in the colon and small bowel. d-dimer and fibrinogen levels are checked in <50 % of patients at diagnosis. Tie2/TEK mutation testing is rarely performed. Gastrointestinal bleeding is the most common complication (54.3 %), requiring endoscopic treatment (36.4 %) by various techniques. ConclusionsThis is the largest cohort study on BRBNS. Diagnosis is mainly based on clinical presentation. d-dimer, fibrinogen and Tie2/TEK mutation testing should be performed in case of suspected BRBNS as it could help confirm the diagnosis.

Seroprevalence of Theileria ovis in Goats from M’Sila Region, Central Algeria

Background: In Algeria, data on the epidemiology of theileriosis in small ruminants are limited. Objectives: The current study investigates the seroprevalence of Theileria spp. in goats from the M’Sila region, Central Algeria. Methods: Blood samples of 128 goats from 19 farms were collected from the locality of Maâdid. The indirect fluorescence antibody test (IFAT) was performed to test the goats’ sera for antibodies against Theileria ovis and Theileria lestoquardi. Results: Out of 128 tested samples, 21 sera (16.40%) were positive for T. ovis antibodies. All samples were seronegative for T. lestoquardi. The seroprevalence of T. ovis varied from 10% to 30% on farms. The seropositivity rates did not differ significantly with age, sex, or breeding system of goats. Tick-infested goats were significantly more seropositive than no-infested goats. Conclusion: The present study reports essential data on the epidemiology of caprine theileriosis from Central Algeria.

Pediatric sporadic Burkitt lymphoma of the head and neck: A case series and analysis of national trends

ObjectiveBurkitt lymphoma (BL) is an aggressive form of non-Hodgkin lymphoma with the sporadic subtype being predominant in North America. The clinical presentations and outcomes of pediatric BL within the head and neck were assessed using both an institutional case series and the Surveillance, Epidemiology, and End Results (SEER) Cancer database. MethodsThe electronic medical record at our quaternary children's hospital was queried over a 22-year period (2000–2022) for BL patients with head and neck manifestations. Demographics, clinical presentation, staging, treatment, and outcomes data were collected and analyzed. A corresponding review of the SEER database from 1975 to 2022 was also performed. ResultsOur institutional case series identified 48 sporadic BL patients with a mean age of 8.7 years, the majority of whom were male (79 %) and white (74 %). The most common primary sites were the cervical lymph nodes (38 %) and (or) palatine tonsils (23 %). Thirty-five patients (73 %) were treated initially for a presumed inflammatory or infectious process before undergoing malignancy work-up, which did not significantly delay time to diagnosis (31.5 vs. 38.8 days, p = 0.27). The SEER database analysis identified 78 cases, 43.5 % of whom were 5–9 years of age, with a similar male (66 %) and Caucasian (76.9 %) predominance. Cervical lymph nodes were also the most common subsite (67 %), followed by the palatine tonsils (13 %). Remission rates were similar, 93.7 % and 94.8 %, respectively, in both the institutional and SEER database cohorts. ConclusionUnilateral cervical lymphadenopathy and asymmetric tonsillar hypertrophy are the most common presentations in sporadic BL in the head and neck. Clinical presentation in patients with BL is often similar to common, insidious pediatric otolaryngology symptoms and a majority of patients initially undergo treatment for presumed infectious or inflammatory disease. Although overall BL disease-free survival is high even for disseminated BL, the prognosis is better for local/regional disease, and minimizing time to diagnosis and treatment should remain a priority.

Oral health inequalities among geriatric population: A systematic review

ABSTRACT As per the World Health Organization, governments should aim to accomplish two significant global milestones by 2030: reducing health disparities and granting universal accessibility to healthcare. The aim of this article was to systematically review the inequalities and understand the multifactorial causation of oral health inequalities among the older adults. Methods: Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) standards were used to carry out the review and is documented in PROSPERO CRD42026695761. Two authors did the search and screening in accordance with the protocol. Electronic databases such as PubMed, Google Scholar, and EBSCOhost articles of the last 10 years were searched for research presenting data on oral health status and oral health related quality of life in the elderly population. Quality assessment was performed using the Newcastle Ottawa Scale (NOS) for retrospective and prospective research. Results: Only 24 studies fulfilled the eligibility criteria and were incorporated into the qualitative synthesis. Multiple aspects of oral health and the related variables influencing disparities in oral health in the elderly population living in institutions have a positive link. Conclusion: The findings support the notion that this demographic consists of weak, dependent individuals who have poor oral health. The vulnerable elderly institutionalized population was recognized and validated, thus helps in providing measures that will eventually focus the risk factors to improve their OHRQoL.

Disentangling negative reinforcement, working memory, and deductive reasoning deficits in elevated BMI

Neuropsychological data suggest that being overweight or obese is associated with a tendency to perseverate behavior despite negative feedback. This deficit might be observed due to other cognitive factors, such as working memory (WM) deficits or decreased ability to deduce model-based strategies when learning by trial-and-error. In the present study, a group of subjects with overweight or obesity (Ow/Ob, n = 30) was compared to normal-weight individuals (n = 42) in a modified Reinforcement Learning (RL) task. The task was designed to control WM effects on learning by manipulating cognitive load and to foster model-based learning via deductive reasoning. Computational modelling and analysis were conducted to isolate parameters related to RL mechanisms, WM use, and model-based learning (deduction parameter). Results showed that subjects with Ow/Ob had a higher number of perseverative errors and used a weaker deduction mechanism in their performance than control individuals, indicating impairments in negative reinforcement and model-based learning, whereas WM impairments were not responsible for deficits in RL. The present data suggests that obesity is associated with impairments in negative reinforcement and model-based learning.

Mechanical properties of pure elements from a comprehensive first-principles study to data-driven insights

Unraveling mechanical properties from fundamental is far from complete despite their vital role in determining applicability and longevity for a given material. Here, we perform a comprehensive study related to mechanical properties of 60 pure elements in bcc, fcc, hcp, and/or diamond structures by means of pure alias shear and pure tensile deformations via density functional theory (DFT) based calculations alongside a broad review of existing literature. The present data compilation enables a detailed correlation analysis of mechanical properties, focusing on DFT-based ideal shear and tensile strengths ( and ), stable and unstable stacking fault energies ( and ), surface energy (), and vacancy activation energy (); and experimental hardness (), ultimate tensile strength (), fracture toughness (), and elongation (). The present work examines models, identifies outliers, and provides insights into mechanical properties, for example, (i) is correlated by , by or , and by ; (ii) data outliers are identified for Cr (related to , , , and ), Be (, , , and ), Hf ( and ), Yb (all properties), and Pt ( vs. ); and (iii) , , , , , , and are highly correlated to elemental attributes, while , , and especially are less correlated due mainly to experimental uncertainty. In particular, the present data compilation provides a solid foundation to model properties such as and of multicomponent alloys and of unstable structures like bcc Ti, Zr, and Hf.

The temperature-precipitation duel and tropical greening during the Early Eocene Greenhouse episode

Under rising anthropogenic CO2, the future of the tropical climate states and the response of the biosphere, specifically the fate of the tropical rainforest (TRF), is uncertain. Therefore, deep-time climate proxy records and model simulations are being extensively utilized to understand the possible response of the TRF community during extreme climate states. However, comprehensive climate-TRF proxy data from the tropical/equatorial region for the paleo-global warming episodes, e.g., Late Paleocene – Early Eocene interval (~56 to 51 Ma, encompassing transient hyperthermal events like Paleocene-Eocene Thermal Maximum [PETM], Eocene Thermal Maximum2 [ETM2]/H1/ Eocene Layer of Mysterious Origin [ELMO], H2, I1, and I2), are very limited and create difficulties in the validation of simulated results. Here we present long-term land surface temperature and precipitation (δ2H and δ18O of pedogenic clay mineral-derived) and TRF diversity (palynology) data from a paleo-equatorial region, spanning the ~56 to 51 Ma interval. Present data suggest that the hydrological response to global warming was not temporally uniform in the paleo-equatorial land. While a significantly increased rainfall buffered the terrestrial temperature during the PETM, an insignificant increase in precipitation and negligible temperature lowering can be observed during the ETM2 hyperthermal event. However, the climate system's response during the other Early Eocene hyperthermals, i.e., H2, I1, and I2, was very similar to the PETM. Despite these small aberrations, the long-term average equatorial land surface temperature (27 ± 4 °C) during the Early Eocene greenhouse episode remained very similar to the modern equatorial temperature (28–30 °C). Rainfall proxy and plant diversity data suggest that the precipitation aided TRFs' resilience and proliferation, possibly through temperature buffering, during this paleo-greenhouse episode.

Assessing racial disparities in gender-affirming surgery utilization and hospital-level experience

Racial and ethnic minority groups, as well as gender minorities seeking gender-affirming care and surgery have historically had difficulties with healthcare access and experience. The intersection of these two groups may result in deficient healthcare for patients of minority racial and ethnic groups seeking gender-affirming surgery. The present study sought to explore differences in gender-affirming genital surgery experience by race. The 2018-2021 Healthcare Utilization Project National Inpatient Survey was queried for gender-affirming surgeries. Demographic, inpatient safety, and hospital-level characteristics were collected. Results were stratified by race and evaluated for significant differences. A total of 4,605 patients were included in the study, 3,345 patients were identified as White (73%), 320 as Black/African American (7%), 485 as Hispanic/Latino (11%), and 110 as Asian/Pacific Islander (2%). Black/African American patients experienced a higher rate of inpatient medical complications than the overall population (1% vs. 3%, P=0.004) and had a longer length of stay (3 vs. 5 days, P<0.001). The highest total charges were observed among Black/African American patients ($130,873, IQR $119,235, P<0.001). Black/African American patients also less often experienced routine discharge (94% vs. 81%, P<0.001) and more often required a higher level of care upon discharge, such as home health care or transfer to another facility (6% vs. 17%, P<0.001). While the healthcare population is becoming more diverse, healthcare disparities still exist among non-White individuals receiving gender-affirming genital surgery. The present data suggest that Black/African American patients receiving gender-affirming genital surgery have more complicated hospital and discharge courses, and experience higher total hospital charges.

Hyperbaric effects on heart rate in professional SCUBA divers in thermal water.

Diving in SCUBA modality modifies human physiology in many ways. These modifications have been studied since Paul Bert in a seminal work. This area of research is very sensible to technological development. At now, it is possible to record heart rate (HR) continuously while diving. The study of HR changes in SCUBA diving at different depths in a constant temperature of thermal water is the objective of the present paper. 18 healthy subjects were enrolled and HR was recorded while SCUBA diving in thermal water at a constant temperature of 33.6∘ C in the deepest Italian pool at Montegrotto (Padova, Italy). Three depths were investigated: -20, -30 and -40 meters. The HR has been recorded with a Galileo SOL diving computer. The dive was subdivided into three phases: descent (DSC), steady on depth (STD), post-dive (RSF), and average HR was evaluated in each phase. Moreover, considering the DSC and STD time duration, a statistical linear regression of HR and relative parameters, intercept and slope, were here assessed. In STD phase, HR slope obtained by regression decreased with depth. A significant difference was found between the slope during STD at -20 vs. -40 m (p ≤ 0.05). Present results emphasized different HR physiological adjustments among diving phases. Firstly, during the DSC, a rapid HR decrease is recognized as probably due to a vagal response; secondly, at STD, the inward blood redistribution requires another physiological adjustment. This latter is depth-dependent because of a reduction of cardiac variability. Present data highlight the important cardiac stress need to counteract the diving activity.

Measurement of fast neutron induced (n,γ) reaction cross-section of 68Zn, 96Zr, 121Sb and 123Sb in the energy range of 1 to 2 MeV

The (n,γ) reaction cross-section for the elements 68Zn, 96Zr, 121Sb and 123Sb, present in the reactor structural/shielding materials, was measured by neutron activation technique in the neutron energy region of 1–2 MeV as very limited data is available in this energy range. Further, the neutron spectrum peaks in this energy region for the fast breeder reactors and proposed accelerator driven sub-critical systems. The natural strontium (natSr) element was used as a neutron flux monitor by considering effective combined reaction cross-section for 86Sr(n,γ)87Srm and 87Sr(n,n′)87Srm reactions. The pellets of mixture of sample and monitor were irradiated by a quasi-mono energetic fast neutron beam, generated by 7Li(p,n)7Be reaction at FOTIA, Bhabha Atomic Research Centre, Mumbai, India. The activity of activation products was measured by off-line gamma-ray spectrometry using High Purity Germanium Detector (HPGe). The present data with improved uncertainty and covariance analysis enhance the cross-section data base for better constraining the evaluated data and theoretical models. The theoretical (n,γ) reaction cross-sections were calculated using TALYS 1.96, which could reasonably explain the present data with the Fermi gas level density prescription.

Oxidation of butane-2,3-dione at high pressure: Implications for ketene chemistry

Ketene (CH2CO) mechanism is a building block for developing combustion kinetic models of practical fuels. To revisit the combustion chemistry related to ketene, oxidation experiments of butane-2,3‑dione (diacetyl, CH3COCOCH3), considered as an effective precursor of CH2CO, are conducted in a jet-stirred reactor (JSR) at 10 bar and temperatures ranging from 650 to 1160 K. Identification and quantification of intermediates are achieved by Fourier transform infrared spectrometry, gas chromatography, and mass spectrometry. A kinetic model of diacetyl is constructed based on recent theoretical and modeling studies on diacetyl and ketene, which has been validated against the present data and experimental data of diacetyl and CH2CO in literature. Generally, the present model can adequately predict most of them, and better predict the methyl-related intermediates under wide pyrolysis and combustion conditions than previous models. Based on modeling analyses, the unimolecular decomposition reaction of diacetyl is the dominant reaction pathway for fuel consumption under different equivalence ratio conditions, especially at high temperatures. Under lean conditions, both the H-atom abstraction reactions by methyl (i.e. CH3COCOCH3 + CH3 = CH4 + CH2CO + CH3CO, R3) and by OH (i.e. CH3COCOCH3 + OH = H2O + CH2CO + CH3CO, R5) are important for diacetyl consumption, while under rich conditions R5 becomes negligible. As the most important intermediates in diacetyl oxidation, the main consumption pathways of CH2CO and CH3 are dependent on the equivalence ratio conditions. Under lean conditions, CH2CO mainly reacts with OH to produce CH2OH and CO (i.e. CH2CO + OH = CH2OH + CO, R10), while methyl reacts with HO2 to produce CH3O and OH (i.e. CH3 + HO2 = CH3O + OH, R20). In contrast, under rich conditions, the addition-elimination reaction between CH2CO and H becomes competitive with R10, while the CH3 self-combination producing C2H6 plays a more important role than the CH3 oxidation pathway R20. Sensitivity analysis of CH2CO shows that not only the reactions of CH2CO, but also those of CH3 are sensitive to CH2CO formation. This is because CH3 related reactions influence the distribution of radical pool, which determines the oxidation reactivity of the reaction system.