Additional Conditions Research Articles

A Constitutive Model for Asymmetric Cyclic Hysteresis of Wrought Magnesium Alloys under Variable Amplitude Loading

A cyclic plasticity constitutive model was developed for materials with asymmetric cyclic behavior to explain the stabilized stress–strain response under variable amplitude loading. The proposed constitutive model incorporated the von Mises yield function with an adjustment to accommodate asymmetric yielding under tension and compression. A combined isotropic–kinematic hardening model was proposed to describe the evolution of the yield surface in the reference uniaxial frame and the actual frame. The history of plastic deformation is memorized by introducing internal variables, accumulated slip, and residual twins, which govern the cyclic flow behavior in the subsequent reversal. The additional conditions required to predict the stabilized hysteresis response of a material under variable amplitude loading were set out and incorporated into the constitutive model. The model was numerically implemented and programmed into a user material (UMAT) subroutine to run with the commercial finite element program, Abaqus/Standard 2019. The model was calibrated using the stabilized hysteresis response of ZEK100 and AZ31B sheets under constant amplitude strain-controlled cyclic loading for different strain amplitudes. To verify the model, constant amplitude and four different variable amplitude load spectra tests were performed and the stabilized stress–strain hysteresis response predicted by the model was compared with test results. It was demonstrated that the results are in very good agreement.

Ultra-stable and highly reactive colloidal gold nanoparticle catalysts protected using multi-dentate metal oxide nanoclusters

Owing to their remarkable properties, gold nanoparticles are applied in diverse fields, including catalysis, electronics, energy conversion and sensors. However, for catalytic applications of colloidal gold nanoparticles, the trade-off between their reactivity and stability is a significant concern. Here we report a universal approach for preparing stable and reactive colloidal small (~3 nm) gold nanoparticles by using multi-dentate polyoxometalates as protecting agents in non-polar solvents. These nanoparticles exhibit exceptional stability even under conditions of high concentration, long-term storage, heating and addition of bases. Moreover, they display excellent catalytic performance in various oxidation reactions of organic substrates using molecular oxygen as the sole oxidant. Our findings highlight the ability of inorganic multi-dentate ligands with structural stability and robust steric and electronic effects to confer stability and reactivity upon gold nanoparticles. This approach can be extended to prepare metal nanoparticles other than gold, enabling the design of novel nanomaterials with promising applications.

The problem of implementing the concept of maximum integration of heterogeneous data in practical navigation

The topic of the work is the research of the problem of the practical realization of opportunistic navigation, which actually consists in the fact that the “signals of opportunity” are not optimized for global navigation according to their original purpose. A hypothesis about the possibility of strategic application of the navigation concept based on the principles of data integration with the objective existence of tactically surmountable difficulties is put forward. In the conditions of vulnerability of the global satellite system, an approach to use an additional source of combined signals in order to continuously ensure accurate geolocation of water transport vehicles is proposed. The comparative assessment confirms the comparability of the positioning error of alternative navigation with the data of classical satellite observations of mobile objects. An assumption about the effectiveness of spline modeling of the cartographic standard of informativeness for the practical organization of the basic principle of opportunistic positioning by analogy with the paradigm of correlation-extreme navigation is made. A computer visualization of a fixed fragment of the ocean gravitational field based on spline approximation is performed in order to optimize the problem of simultaneous localization and three-dimensional representation of the ship movement in a graphical environment unaffiliated with foreign software. A hybrid algorithm for mathematical synthesis of the navigational isosurface has been tested as a harmonized support for the navigation staff to implement the “terrain-referenced procedure” in the landscape coordinate space. The variants of the “ambiguity resolution” problem implementation in the issue of maximum integration of heterogeneous navigation data are considered. The probability of practical use of the opportunistic navigation postulates in marine applications, taking into account the “navigation gap” factor for leveling local satellite incapacity with a real possibility of countering malicious interception of ship control, is estimated. The expediency of using the factor of observational reckoning of the vessel path as an additional condition for navigation safety in the aspect of packet processing of the “signals of opportunity” slot is substantiated.

Exploratory factor and confirmatory analyses of the polycystic ovary syndrome health-related quality of life questionnaire (PCOSQ-50)

BackgroundA condition-specific instrument is necessary to measure the health-related quality of life among those with polycystic ovary syndrome (PCOS), the most common chronic endocrinopathy among women. The first instrument was developed in 1988, followed by several revisions. However, further recommendations from all versions include additional application and measurement among different cultural populations of women with PCOS and psychometric testing based on use among larger samples of women with PCOS. Thus, the purpose of this study was to explore the factor structure of the Polycystic Ovary Syndrome Questionnaire (PCOSQ-50) using an international cross-sectional survey data from women with PCOS aged 18–42 years.MethodsUsing data from the largest known international cross-sectional study of women with PCOS aged 18–42 years (n = 935) to date, exploratory factor and confirmatory analyses were conducted for the PCOSQ-50, followed by factor labeling using a thematic analysis approach.ResultsRespondents were 31.0 ± 5.8 years of age, mostly White (72%), well-educated (56% had a college degree), married (69%), and employed full-time (65%). Three-quarters (74%) of the sample had one or more chronic conditions in addition to PCOS. Approximately 20% of the respondents originated from countries such as the United Kingdom, Australia, South Africa, etc. The PCOSQ-50 demonstrated good reliability but may be best described using a 7-factor model. The 7-factor model revealed goodness-of-fit. Thematic analysis suggested the following labels of those seven factors: hirsutism, fertility, isolation/trepidation, sexual function, self-esteem, emotional, and obesity.ConclusionMore research is needed to adapt the current PCOSQ-50, as well as to create an age-appropriate PCOS-specific HRQoL instrument for peri-postmenopausal women with PCOS.

Chemical kinetics analysis of ammonia/dimethyl ether combustion under water addition conditions

Ammonia has gained considerable interest as a high-energy-density, zero-carbon fuel with potential as a clean energy source for future applications. Nonetheless, its widespread industrial use is constrained by challenges associated with low flammability and elevated levels of NOx emissions. To address the low flammability issue, this study introduces dimethyl ether (DME), a fuel known for its high laminar flame speed, into pure ammonia combustion systems. Moreover, we implement moderate and low-temperature diffusion combustion by incorporating water vapor into high-temperature air, aiming to minimize NOx emissions. We examined the effects of NH3/DME and water vapor mixing ratios on variables including laminar flame speed, key free radicals, NO emissions, and reaction pathways. Computational simulations were conducted using the PREMIX module within Chemkin Pro based on a modified Meng model, which was initially validated against experimental data. Our results indicate that increasing DME concentrations lead to a notable rise in laminar flame speed and the concentration of O, H, and OH radicals. Concurrently, NO concentrations also increased due to DME's oxygen-bearing nature, which enhances the oxidation of N-containing radicals. Conversely, elevating the water vapor content results in reduced laminar flame speed, decreased free radical peaks, and diminished NO emissions. Rate of production analyses reveal that specific reactions, such as HNO + HNO + H2, HNO + OHNO + H2O, and NH + ONO + H, significantly contribute to NO formation by consuming active O, H, and OH radicals.

Development and validation of new multimorbidity-weighted index for ICD-10-coded electronic health record and claims data: an observational study

ObjectiveMap multimorbidity-weighted index (MWI) conditions to International Classification of Diseases, 10th Revision (ICD-10), expand the conditions and codes to develop a new ICD-10-coded MWI (MWI-ICD10) and updated MWI-ICD9, and assess...

Physics-informed neural networks with domain decomposition for the incompressible Navier–Stokes equations

Physics-informed neural network (PINN) has emerged as a promising approach for solving differential equations in recent years. However, their application to large-scale complex problems has faced challenges regarding accuracy and efficiency. To address these limitations, domain decomposition has gained popularity as an effective strategy. This paper studies a domain decomposition PINN method for solving incompressible Navier–Stokes equations. We assess the method's predicted accuracy, convergence, and the impact of different strategies on performance. In the domain decomposition PINN method, individual PINN is employed for each subdomain to compute local solutions, which are seamlessly connected by enforcing additional continuity conditions at the interfaces. To improve the method's performance, we investigate various continuity conditions at the interfaces and analyze their influence on the predictive accuracy and interface continuity. Furthermore, we introduce two approaches: the dynamic weight method and a novel neural network architecture incorporating attention mechanisms, both aimed at mitigating gradient pathologies commonly encountered in PINN methods. To demonstrate the effectiveness of the proposed method, we apply it to a range of forward and inverse problems involving diverse incompressible Navier–Stokes flow scenarios. This includes solving benchmark problems such as the two-dimensional (2D) Kovasznay flow, the three-dimensional (3D) Beltrami flow, the 2D lid-driven cavity flow, and the 2D cylinder wake. Additionally, we conduct 3D blood flow simulations for synthetic flow geometries and real blood vessels. The experimental results demonstrate the capability and versatility of the domain decomposition PINN method in accurately solving incompressible Navier–Stokes flow problems.

Perceptions on artificial intelligence-based decision-making for coexisting multiple long-term health conditions: protocol for a qualitative study with patients and healthcare professionals

IntroductionCoexisting multiple health conditions is common among older people, a population that is increasing globally. The potential for polypharmacy, adverse events, drug interactions and development of additional health conditions complicates...

Effect of Rare Earth Elements Addition and Sintering Conditions on the Microstructure and Microhardness of Inconel 718

Effect of Rare Earth Elements Addition and Sintering Conditions on the Microstructure and Microhardness of Inconel 718

Health care for women during pregnancy, childbirth and the postpartum period as well as for newborns financed from public funds

Purpose – the aim of the article is to describe health care services for women during pregnancy, childbirth and the postpartum period, including newborn care, provided in the period 2017–2021.Method – the analyses included data from the Council of Ministers’ reports on the implementation and effects of the application of the Act on Family Planning, Protection of the Human Foetus and Conditions for Termination of Pregnancy, as well as demographic data published by the Statistics Poland.Results – it was shown that in the period 2017– 2021, the number of women who received the service specified in the advice given during pregnancy decreased. However, the share of births registered as coordinated care for pregnant women I (KOC I) [pl. Koordynowana Opieka nad Ciężarną] in the total number of births increased, although ultimately they constituted a small percentage of the number of births in the country. Births carried out as KOC II/III had a higher and growing share in the number of births each year. The number of patients receiving coordinated children's care, perinatal palliative care services, and the number of pregnant participants in the Prenatal Testing Program also increased. At the same time, access to the above-mentioned services depended on the place of residence of the potential patient, since relevant service providers were available only in some voivodships, or, as in the Prenatal Testing Program, obtaining the service depended on meeting strict conditions.Conclusion – it is necessary to increase the availability of the analysed services by introducing service providers in voivodeships where they are lacking. It is also necessary to enable all interested pregnant women to participate in the Prenatal Testing Program without having to meet additional conditions.

A study on the spectral properties of covariance type matrices with isotropic log-concave column vectors.

The limiting spectral distribution of matrix [Formula: see text] is considered in this paper. Existing results always focus on the condition of modifying Tn, but for Xn, it is usually assumed to be a matrix composed of n × N independent identically distributed elements. Here we specify the joint distribution of column vectors of Xn. In particular, entries on the same column of Xn are correlated, in contrast with more common independence assumptions. Assuming that the columns of Xn are random vectors following the isotropic log-concave distribution, and under some additional regularity conditions, we prove that the empirical spectral distribution [Formula: see text] of matrix Bn converges to a deterministic probability distribution F almost surely. Moreover, the Stieltjes transformation m = m(z) of F satisfies a deterministic form of equation, and for any [Formula: see text], it is the unique solution of the equation.

DISEASE MODELING IN INFLAMMATORY BOWEL DISEASE (IBD) USING PATIENT-DERIVED EXPLANTS (PDE) REVEALS CHEMOKINES AS A RELEVANT TARGET OF JAK INHIBITION

Abstract Despite a recent explosion of approved drugs for IBD that primarily target cytokines and T-cell trafficking, therapeutic response rates remain low (30-50 %), underscoring the need for more efficacious treatments with fewer side effects. From a drug development perspective, it takes over 10 years for a new drug to reach the market with >90% attrition rates. The realization that drug testing in animal models does not always translate to humans, particularly for complex diseases of high heterogeneity like IBD, leaving a significant gap in pre-clinical drug evaluation. Technologies such as organoids or “gut on a chip” attempted to fulfill this gap, but among their limitations are lack of tissue complexity and an externally induced, and often biased, “disease state” that fails to capture patient heterogeneity and underlying disease mechanisms. We developed a Therapeutic Response Predictor Assay for IBD (TheRPA _ibd) which is based on establishing short term explant cultures from the patient’s diseased tissue (PDE). PDEs can be treated with various candidate drugs or their combinations and inform whether an individual patient is a responder or non-responder to the particular treatment. TheRPA_ibd has been clinically validated for anti-TNF with a predictive accuracy of 0.87 (p<0.0001). TheRPA_ibd was used to comparatively evaluate 6 JAK inhibitors (JAKi) with different JAK isoform selectivity (tofacitinib, baricitinib, upadacitinib, ritlecitinib, filgotinib, and peficitinib). PDEs were derived from mucosal inflamed biopsies obtained during colonoscopy or surgical resection (26 CD/11 UC). JAKi responses were evaluated using targeted and bulk gene expression, antibody arrays and multiplex ELISA. Our analysis, in addition to previously described cytokines, identified several chemokines as downstream targets of JAK inhibition: CXCL1; CXCL2; CXCL3; CXCL5; CXCL8; CXCL9; CXCL10; CXCL11; CXCL16; CCL10; CCL20. Of clinical importance, interrogation of publicly available gene expression IBD datasets confirmed a robust dysregulation of those targets in both UC and CD. Such findings open new avenues for exploring chemokine-driven pathways as potential therapeutic targets in IBD and potentially additional inflammatory conditions. From a mechanistic perspective, JAK1 or JAK3 selective inhibitors appeared to lack broader cytokine and chemokine inhibition compared to pan-JAKi. Notably, as a target, TYK2 was found to be critical for maximizing the anti-inflammatory effects of JAKi. The PDE-based assay (TheRPA) not only enables selection of patient-tailored treatments but also as a “clinical trial in a dish” platform can efficiently contribute to candidate drug de-risking and prioritization. As a proof of concept, using this technology we have been able to demonstrate efficacy in CD of certain JAK inhibitors prior to their FDA approval for this indication.

Structural and Psychosocial Syndemic Conditions and Condomless Anal Intercourse Among Transgender Women - National HIV Behavioral Surveillance Among Transgender Women, Seven Urban Areas, United States, 2019-2020.

Psychosocial and structural syndemic conditions, including polydrug use and experiencing homelessness, frequently co-occur and might jointly increase HIV risk. Limited studies have assessed racial and ethnic differences in exposure to syndemic conditions and behaviors associated with HIV transmission among transgender women. This report examines the relation between syndemic conditions and condomless anal intercourse (CAI) among transgender women in seven urban areas in the United States to develop HIV prevention interventions for transgender women. During 2019-2020, transgender women in seven urban areas were recruited using respondent-driven sampling for a biobehavioral survey. Reported syndemic conditions (psychosocial: polydrug use, sexual violence, and psychological distress; structural: homelessness, incarceration, and exchange sex) were summed to create a syndemic score. Using modified Poisson regression to account for RDS, the study assessed whether the strength of the association between syndemic score and CAI differed by race and ethnicity. To assess additive interaction, the relative excess prevalence owing to interaction (REPI) and 95% CIs for selected pairs of syndemic conditions on CAI prevalence stratified by race and ethnicity were estimated. Of 1,348 transgender women (Black=546, White=176, and Hispanic=626), 55% reported CAI; and 24% reported ≥3 syndemic conditions. Reporting additional syndemic conditions was associated with CAI for White, Hispanic, and Black participants. The association was significantly stronger for White than Black and Hispanic participants. Limited significant superadditive interactions were found, although the majority were between structural syndemic conditions. Racial and ethnic differences in REPI estimates were observed. Reporting more syndemic conditions was associated with increased CAI across racial and ethnic groups, demonstrating that HIV prevention efforts for transgender women should address structural and psychosocial syndemic conditions. Results differed by race and ethnicity, indicating that syndemic-focused interventions for transgender women should be tailored to racial and ethnic groups.

Potent antitumor activity of anti-HER2 antibody-topoisomerase I inhibitor conjugate based on self-immolative dendritic dimeric-linker

Antibody-drug conjugates (ADCs) are a rapidly expanding class of anticancer therapeutics, with 14 ADCs already approved worldwide. We developed unique linker technologies for the bioconjugation of drug molecules with controlled-release applications. We synthesized cathepsin-cleavable ADCs using a dimeric prodrug system based on a self-immolative dendritic scaffold, resulting in a high drug-antibody ratio (DAR) with the potential to reach 16 payloads due to its dendritic structure, increased stability in the circulation and efficient release profile of a highly cytotoxic payload at the targeted site. Using our novel cleavable linker technologies, we conjugated the anti-human epidermal growth factor receptor 2 (anti-HER2) antibody, trastuzumab, with topoisomerase I inhibitors, exatecan or belotecan. The newly synthesized ADCs were tested in vitro on mammary carcinoma cells overexpressing human HER2, demonstrating a substantial inhibitory effect on the proliferation of HER2-positive cells. Importantly, a single dose of our trastuzumab-based ADCs administered in vivo to mice bearing HER2-positive tumors, showed a dose-dependent inhibition of tumor growth and survival benefit, with the most potent antitumor effects observed at 10 mg/kg, which resulted in complete tumor regression and survival of 100% of the mice. Overall, our novel dendritic technologies using the protease-cleavable Val-Cit linker present an opportunity for the development of highly selective and potent controlled-released therapeutic payloads. This strategy could potentially lead to the development of novel and effective ADC technologies for patients diagnosed with HER2-positive cancers. Moreover, our proposed ADC linker technology can be implemented in additional medical conditions such as other malignancies as well as autoimmune diseases that overexpress targets, other than HER2.

P238 Autoimmune comorbidities in microscopic colitis: retrospective analysis of consecutive single centre patients

Abstract Background Microscopic colitis (MC) is an autoimmune inflammatory condition that causes watery diarrhoea along with other symptoms like bowel incontinence, resulting in impaired quality of life and morbidity. MC is localized to the colon, although other autoimmune disorders are known to be more prevalent among MC patients. Methods A retrospective analysis of consecutive MC patients treated in Lithuanian University of Health Sciences Hospital Kauno Klinikos over the last 6 years was performed. Patient information was obtained from electronic records and reviewed for demographic characteristics and diagnosed conditions. Results 94 MC patients were treated in our centre since 2017, 46 (49 %) with collagenous colitis (CC), 39 (41.5 %) with lymphocytic colitis (LC), 2 (2.1 %) with incomplete CC and 7 (7.4 %) with incomplete LC. 77 patients were female (82 %). Median age was 59 years [44.8-70.3]. There was a tendency for men to be younger (median 42 [37-68]) than women (median 60 [50-70.5]) but not significantly (p>0.05). 31 MC patients (33 %) we diagnosed with concomitant autoimmune disorders. 20 patients (21.3 %) had autoimmune thyroiditis, 7 (7.4 %) had coeliac disease, 7 (7.4 %) had autoimmune skin conditions, 5 (5.3 %) had rheumatoid arthritis, 1 (1.1 %) had spondyloarthritis and 2 (2.1 %) had autoimmune hepatitis. 9 patients (9.6 %) had 2 autoimmune conditions in addition to MC and 1 patient (1.1 %) had 3. 16 (34.8 %) CC patients, 11 (28.2 %) LC patients and 4 (57 %) incomplete LC patients had autoimmune comorbidities. 3 (6.5 %) CC patients, 3 (7.7 %) LC patients and 1 (14.3) incomplete LC patient had coeliac disease. Autoimmune thyroiditis was observed in 11 (23.9 %) CC patients, 6 (15.4 %) LC patients and 3 (42.9 %) incomplete LC patients. 2 (4.3 %) CC patients and 3 (7.7 %) LC patients had rheumatoid arthritis. 5 (10.9 %) CC patients and 2 (5.1 %) LC patients has autoimmune skin disorders. The differences between CC and LC patients were not statistically significant. Both patients with autoimmune hepatitis had LC and the patient with spondyloarthritis had incomplete LC. Conclusion MC patients in our centre were frequently diagnosed with additional autoimmune disorders warranting vigilance in clinical practice. There was no difference between CC and LC patients. Incomplete LC patients had a higher proportion of autoimmune comorbidities and though the number of cases was low, this opens up prospects for future investigation.

Global existence and decay rates of solutions to the Oldroyd-B model with stress tensor diffusion

In this paper, we consider the Oldroyd-B model with stress tensor diffusion in Rd with d≥2. We first establish the global well-posedness of solutions to this model for small initial data (u0,τ0)∈(B˙p,1dp−1∩B˙p,1dp+1)d×(B˙p,1dp)d×d with 1≤p<∞. Furthermore, under some additional L2 type conditions on (u0,τ0), but without any more smallness restrictions, we get the L2 decay rates of all derivatives of (u,τ). It is shown that the velocity u decays as fast as the solution to the corresponding homogeneous linear heat equation, and the symmetry τ decays as fast as ∇u. In particular, when d=3 the velocity u admits the decay rate faster than (1+t)−34 in L2.

Fe2B layer growth kinetics on ASTM A307 steel evaluated by two diffusion models

Abstract In this study, we implemented two simple models to simulate the growth of the Fe2B layer on ASTM A307 steel through boriding. The first model considered steady-state boron diffusion, while the second model incorporated transient regime effects. In the steady-state model, the boron concentration profile within the Fe2B layer exhibited linearity. By correlating the boron chemical potential with the inward mass flux at the (Fe2B/substrate) interface, we confirmed the parabolic nature of layer growth. Both models were employed to determine the boron activation energies, yielding the same value of approximately 164 kJ mol−1. Experimental validation of the two models was conducted under two additional boriding conditions (1323 K for 1.5 and 2 h). Finally, the simulated layer thicknesses matched with the experimental values.

Healthcare contact days among older adults living with dementia.

For older adults with dementia and their care partners, accessing health care outside the home involves substantial time, direct and indirect costs, and other burdens. While prior studies have estimated days spent by these individuals in or out of hospitals and nursing homes, ambulatory care burdens are likely substantial yet poorly understand. Therefore, we characterized "health care contact days"-days spent receiving ambulatory or institutional care-in this population. We used 2019 Medicare Current Beneficiary Survey data linked to claims for community-dwelling, ≥65-year-old adults with dementia in Traditional Medicare. We measured contact days including ambulatory days (with an office visit, test, imaging, procedure, or treatment) and institutional days (spent in an emergency department, hospital, skilled nursing facility, or hospice facility). We described variation and patterns in contact days. Using multivariable Poisson regression, we identified sociodemographic and clinical factors associated with contact days. In weighted analyses, 887 older adults with dementia (weighted: 2.9 million) had mean (SD) 31.1 (33.7) total contact days/year, of which 21.7 (20.6) were ambulatory. Ten percent had ≥68 contact days in the year. One-third (34%) of ambulatory contact days involved multiple services. In multivariable models, receipt of more ambulatory contact days was associated with younger age (65-74 reference vs. -32.3% [95% CI: -42.2%, -20.7%] for 85+), higher income (>200% Federal Poverty Level [FPL] reference versus -16.6% [95% CI: -26.7%, -5.0%] for ≤200% FPL), and lack of functional impairment (reference versus -14.6% [95% CI: -23.7%, -4.4%]). Each additional chronic condition was associated with 8.2% (95% CI: 6.7%, 9.8%) more ambulatory contact days. Older adults with dementia spent 31 days a year accessing care which was mostly ambulatory. These days varied widely by both clinical and sociodemographic factors. These results highlight the need to reduce patient burden through strategies such as reducing unneeded care, coordinating care, and shifting care to home settings through telemedicine and home care.

Optimization of Ca additive and HIP condition in fabrication of the transparent MgAl2O4 ceramics

The amount of Ca addtive as well as the sintering condition on the in-line transmittance and the flexural strength of the transparent MgAl2O4 spinel ceramics were optimized. In-line transmittance and mechanical properties were also dependent on the hot-isostatic-press(HIP) temperature. Elevated HIP temperature induced the abnormal grain growth, which resulted the large trapped pores inside the grain, which resulted the in-line transmittance degraded. Elevated HIP together with larger Ca amount accelerated the generation of abnormal grain growth (AGG) and the secondary phases, hence the optical and mechanical properties degraded. The optimized condition was the addition of 800 ppm Ca with HIP at 1500 °C. Big scattering sources, pore clusters as well as the secondary calcium aluminate phases, were restricted and homogeneous microstructure without AGG was revealed. Hence, both the in-line transmittance and the strength were optimized as 84% and 323 MPa, simultaneously.

The Dependence on Hue, Value and Opacity of Real-Time- and Post-Curing Light Transmission in a Nano-Hybrid Ormocer.

This study aims to quantify the influence of hue, value and opacity on the variation in light transmittance of a full color palette of an ormocer-based dental composite. Samples with a thickness of 2 mm were cured in real time while the incident irradiance and light transmittance were recorded with a spectrophotometer, either in real time during the polymerization or through the polymerized composite at different exposure distances. Across the entire shade range, light attenuation was high, varying between 70.3% and 92.1%. The light transmittance during polymerization increased exponentially with exposure time in all shades. The differences between the cured and uncured composites decrease with increasing value and with increasing opacity within a value. The pattern of variation in light transmittance with increasing value is non-linear and depends on the hue, but not on the opacity within a hue. Small variations in value in lighter shades of hue B reduce the transmitted light more than in hue A, while the opposite is true for darker shades. The results strongly suggest an adequate curing of the lower increments in larger restorations, as the additional light expected from curing the upper increments is very small, regardless of hue, value or opacity. An additional unfavorable condition by increasing the exposure distance consistently contributes to a reduction in light transmission and thus further supports the above statement.