Assessing patterns in cancer screening use by race and ethnicity during the coronavirus pandemic using electronic health record data.

BACKGROUND: Efforts to prevent the spread of the coronavirus led to dramatic reductions in nonemergency medical care services during the first several months of the COVID-19 pandemic. Delayed or missed screenings can lead to more advanced stage cancer diagnoses with potentially worse health outcomes and exacerbate preexisting racial and ethnic disparities. The objective of this analysis was to examine how the pandemic affected rates of breast and colorectal cancer screenings by race and ethnicity. METHODS: We analyzed panels of providers that placed orders in 2019-2020 for mammogram and colonoscopy cancer screenings using electronic health record (EHR) data. We used a difference-in-differences design to examine the extent to which changes in provider-level mammogram and colonoscopy orders declined over the first year of the pandemic and whether these changes differed across race and ethnicity groups. RESULTS: We found considerable declines in both types of screenings from March through May 2020, relative to the same months in 2019, for all racial and ethnic groups. Some rebound in screenings occurred in June through December 2020, particularly among White and Black patients; however, use among other groups was still lower than expected. CONCLUSIONS: This research suggests that many patients experienced missed or delayed screenings during the first few months of the pandemic, which could lead to detrimental health outcomes. Our findings also underscore the importance of having high-quality data on race and ethnicity to document and understand racial and ethnic disparities in access to care.

Earned Income Tax Credit Receipt By Hispanic Families With Children: State Outreach And Demographic Factors.

The Earned Income Tax Credit (EITC), the largest refundable tax credit for low-to-middle-income US families with children, has been shown to improve maternal and child health and reduce public spending on health. However, many eligible families do not receive it. This study used 2014 Survey of Income and Program Participation data to explore predictors of EITC receipt among Hispanic families, an understudied segment of the eligible population. We found lower likelihoods of receipt among Hispanic income-eligible families, even those who were eligible US citizens by naturalization, compared with their peers. Parent self-employment and lower English language proficiency were also associated with lower EITC receipt. With new data collected on state policies, we found that states' granting of drivers' licenses to undocumented people, availability of government information in Spanish, and employer mandates to inform employees were associated with greater EITC receipt among all income-eligible families, including Hispanic families. These findings showcase ways in which information and outreach at the state level can support the equitable receipt of tax refunds and similar types of benefits distributed through the tax system.

Self-interaction-corrected Kohn-Sham effective potentials using the density-consistent effective potential method.

Density functional theory (DFT) and beyond-DFT methods are often used in combination with photoelectron spectroscopy to obtain physical insights into the electronic structure of molecules and solids. The Kohn-Sham eigenvalues are not electron removal energies except for the highest occupied orbital. The eigenvalues of the highest occupied molecular orbitals often underestimate the electron removal or ionization energies due to the self-interaction (SI) errors in approximate density functionals. In this work, we adapt and implement the density-consistent effective potential method of Kohut, Ryabinkin, and Staroverov [J. Chem. Phys. 140, 18A535 (2014)] to obtain SI-corrected local effective potentials from the SI-corrected Fermi-Löwdin orbitals and density in the Fermi-Löwdin orbital self-interaction correction scheme. The implementation is used to obtain the density of states (photoelectron spectra) and HOMO-LUMO gaps for a set of molecules and polyacenes. Good agreement with experimental values is obtained compared to a range of SI uncorrected density functional approximations.

Inactivation of Listeria and E. coli by Deep-UV LED: effect of substrate conditions on inactivation kinetics.

Irradiation with deep-ultraviolet light-emitting diodes (DUV LEDs) is emerging as a low energy, chemical-free approach to mitigate microbial contamination, but the effect of surface conditions on treatment effectiveness is not well understood. Here, inactivation of L. innocua and E. coli ATCC25922, as examples of Gram-positive and Gram-negative bacteria, respectively, by DUV LED of 280 nm wavelength was studied. Surface scenarios commonly encountered in environmental, clinical or food processing environments were used: nutrient rich surfaces, thin liquid films (TLF), and stainless steel surfaces (SS). DUV LED exposure achieved 5-log reduction for both strains within 10 min in most scenarios, except for TLF thicker than 0.6 mm. Inactivation kinetics in TLF and on dry SS followed the Weibull model (0.96 ≤ R2 ≤ 0.99), but the model overestimated inactivation by small-dose DUV on wet SS. Confocal microscopy revealed in situ that bacteria formed a dense outer layer at the liquid-air interface of the liquid droplet, protecting the cells inside the droplet from the bactericidal DUV. This resulted in lower than anticipated inactivation on wet SS at small DUV doses, and deviation from the Weibull model. These findings can be used to design effective DUV LED disinfection strategies for various surface conditions and applications.

Fermi-Löwdin orbital self-interaction correction using the strongly constrained and appropriately normed meta-GGA functional.

Despite the success of density functional approximations (DFAs) in describing the electronic properties of many-electron systems, the most widely used approximations suffer from self-interaction errors (SIEs) that limit their predictive power. Here, we describe the effects of removing SIE from the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation using the Fermi-Löwdin Orbital Self-Interaction Correction (FLOSIC) method. FLOSIC is a size-extensive implementation of the Perdew-Zunger self-interaction correction (PZ-SIC) formalism. We find that FLOSIC-SCAN calculations require careful treatment of numerical details and an integration grid that yields reliable accuracy with this approach. We investigate the performance of FLOSIC-SCAN for predicting a wide array of properties and find that it provides better results than FLOSIC-LDA and FLOSIC-PBE in nearly all cases. It also gives better predictions than SCAN for orbital energies and dissociation energies where self-interaction effects are known to be important, but total energies and atomization energies are made worse. For these properties, we also investigate the use of the self-consistent FLOSIC-SCAN density in the SCAN functional and find that this DFA@FLOSIC-DFA approach yields improved results compared to pure, self-consistent SCAN calculations. Thus, FLOSIC-SCAN provides improved results over the parent SCAN functional in cases where SIEs are dominant, and even when they are not, if the SCAN@FLOSIC-SCAN method is used.

Fermi-Löwdin orbital self-interaction correction to magnetic exchange couplings.

We analyze the effect of removing self-interaction error on magnetic exchange couplings using the Fermi-Löwdin orbital self-interaction correction (FLOSIC) method in the framework of density functional theory (DFT). We compare magnetic exchange couplings obtained from self-interaction-free FLOSIC calculations with the local spin density approximation (LSDA) with several widely used DFT realizations and wave function based methods. To this end, we employ the linear H-He-H model system, six organic radical molecules, and [Cu2Cl6]2- as representatives of different types of magnetic interactions. We show that the simple self-interaction-free version of LSDA improves calculated couplings with respect to LSDA in all cases, even though the nature of the exchange interaction varies across the test set, and in most cases, it yields results comparable to modern hybrids and range-separated approximate functionals.

Self-interaction corrections applied to Mg-porphyrin, C60, and pentacene molecules.

We have applied a recently developed method to incorporate the self-interaction correction through Fermi orbitals to Mg-porphyrin, C60, and pentacene molecules. The Fermi-Löwdin orbitals are localized and unitarily invariant to the Kohn-Sham orbitals from which they are constructed. The self-interaction-corrected energy is obtained variationally leading to an optimum set of Fermi-Löwdin orbitals (orthonormalized Fermi orbitals) that gives the minimum energy. A Fermi orbital, by definition, is dependent on a certain point which is referred to as the descriptor position. The degree to which the initial choice of descriptor positions influences the variational approach to the minimum and the complexity of the energy landscape as a function of Fermi-orbital descriptors is examined in detail for Mg-porphyrin. The applications presented here also demonstrate that the method can be applied to larger molecular systems containing a few hundred electrons. The atomization energy of the C60 molecule within the Fermi-Löwdin-orbital self-interaction-correction approach is significantly improved compared to local density approximation in the Perdew-Wang 92 functional and generalized gradient approximation of Perdew-Burke-Ernzerhof functionals. The eigenvalues of the highest occupied molecular orbitals show qualitative improvement.

Density functional study of the electronic structure of dye-functionalized fullerenes and their model donor-acceptor complexes containing P3HT.

We study the electronic structure of C60 fullerenes functionalized with a thiophene-diketo-pyrrolopyrrole-thiophene based chromophore using density functional theory combined with large polarized basis sets. As the attached chromophore has electron donor character, the functionalization of the fullerene leads to a donor-acceptor (DA) system. We examine in detail the effect of the linker and the addition site on the electronic structure of the functionalized fullerenes. We further study the electronic structure of these DA complexes with a focus on the charge transfer excitations. Finally, we examine the interface of the functionalized fullerenes with the widely used poly(3-hexylthiophene-2,5-diyl) (P3HT) donor. Our results show that all functionalized fullerenes with an exception of the C60-pyrrolidine [6,6], where the pyrrolidine is attached at a [6,6] site, have larger electron affinities relative to the pristine C60 fullerene. We also estimate the quasi-particle gap, lowest charge transfer excitation energy, and the exciton binding energies of the functionalized fullerene-P3MT model systems. Results show that the exciton binding energies in these model complexes are slightly smaller compared to a similarly prepared phenyl-C61-butyric acid methyl ester (PCBM)-P3MT complex.

Site specific atomic polarizabilities in endohedral fullerenes and carbon onions.

We investigate the polarizability of trimetallic nitride endohedral fullerenes by partitioning the total polarizability into site specific components. This analysis indicates that the polarizability of the endohedral fullerene is essentially due to the outer fullerene cage and has insignificant contribution from the encapsulated unit. Thus, the outer fullerene cages effectively shield the encapsulated clusters and behave like Faraday cages. The polarizability of endohedral fullerenes is slightly smaller than the polarizability of the corresponding bare carbon fullerenes. The application of the site specific polarizabilities to C60@C240 and C60@C180 onions shows that, compared to the polarizability of isolated C60 fullerene, the encapsulation of the C60 in C240 and C180 fullerenes reduces its polarizability by 75% and 83%, respectively. The differences in the polarizability of C60 in the two onions is a result of differences in the bonding (intershell electron transfer), fullerene shell relaxations, and intershell separations. The site specific analysis further shows that the outer atoms in a fullerene shell contribute most to the fullerene polarizability.

The electronic structure and charge transfer excited states of the endohedral trimetallic nitride C80 (I(h)) fullerenes-Zn-tetraphenyl porphyrin dyads.

Endohedral fullerenes offer the possibility of tuning their properties through a choice of the endohedral unit. The Sc3N@C80 fullerene is the most abundant fullerene after C60 and C70. Recently, Sc3N@C80 has been tested for light harvesting properties with encouraging results. In this work, we study the electronic structure of three endohedral fullerene-Zn tetraphenyl porphyrin complexes using density functional theory. The binding between the components in these complexes arises due to van der Waals interaction. A fragment orbital analysis is carried out to examine the interaction between the two components which shows that a small charge transfer occurs in the ground state from the ZnTPP to the fullerenes and that the orientation of the Sc3N plane affects the ground state charge transfer. The charge transfer excited state energies are calculated using our perturbative delta-SCF method. A comparison with earlier calculations shows that the charge transfer excitation energy increases as C60-ZnTPP < C70-ZnTPP < Sc3N@C80-ZnTPP < Y3N@C80-ZnTPP. The orientation of the endohedral unit does not influence the excitation energy in the donor-acceptor complexes.

The effect of structural changes on charge transfer states in a light-harvesting carotenoid-diaryl-porphyrin-C60 molecular triad.

We present a detailed study of charge transfer (CT) excited states for a large number of configurations in a light-harvesting Carotenoid-diaryl-Porphyrin-C60 (CPC60) molecular triad. The chain-like molecular triad undergoes photoinduced charge transfer process exhibiting a large excited state dipole moment, making it suitable for application to molecular-scale opto-electronic devices. An important consideration is that the structural flexibility of the CPC60 triad impacts its dynamics in solvents. Since experimentally measured dipole moments for the triad of ∼110 D and ∼160 D strongly indicate a range in structural variability in the excited state, studying the effect of structural changes on the CT excited state energetics furthers the understanding of its charge transfer states. We have calculated the variation in the lowest CT excited state energies by performing a scan of possible variation in the structure of the triad. Some of these configurations were generated by incrementally scanning a 360° torsional (dihedral) twist at the C60-porhyrin linkage and the porphyrin-carotenoid linkage. Additionally, five different CPC60 conformations were studied to determine the effect of pi-conjugation and particle-hole Coulombic attraction on the CT excitation energies. Our calculations show that configurational changes in the triad induces a variation of ∼0.6 eV in CT excited state energies in the gas-phase. The corresponding calculated excited state dipoles show a range of 47 D-188 D. The absorption spectra and density of states of these structures show little variation except for the structures where the porphyrin and aryl conjugation is changed.

Frecuencia de muerte según tipo de diarrea / Mortality rate according type of diarrhoea

La proporción de muertes por diarrea ocuosa aguda en niños tiende a disminuir en algunos países, con aumento relativo de las defunciones asociadas a diarrea persistente o a disentería. Con el objeto de conocer la evolución de su frecuencia relativa en los últimos once años en un hospital pediátrico de tercer nivel en la Ciudad de México, se incluyeron en este estudio los niños hospitalizados que ingresaron con diagnóstico de diarrea y que fallecieron, en el periodo comprendido entre el 1o. de enero de 1982 y el 31 de diciembre de 1992. En total, murieron 419 pacientes con enfermedad diarreica: 252 (60 por ciento) ingresaron con diarrea aguda, 150 (36 por ciento) con diarrea persistente y 17 (14 por ciento) con disentería. La diarrea acuosa fue el tipo más frecuente, con variación anual decreciente de 73 a 46 por ciento, seguida por incremento proporcional de la diarrea persistente, desde 26 hasta 47 por ciento; la disentería se mantuvo siempre con la frecuencia más baja. Aunque hacen falta otras investigaciones semejantes para conocer si esta tendencia es similar en otras poblaciones, los resultados del presente estudio sugieren dar mayor atención a la prevención de las diarreas de evolución prolongada, a través de mejorar el manejo del episodio agudo inicial y la alimentación de los niños