The association between affordable care act implementation and the prevalence of women having ever received a Pap smear.

Background: To assess if implementation of the 2010 Patient Protection and Affordable Care Act (ACA) was associated with changes in the prevalence of women having ever received a pap smear.

Methods: This study utilised the publicly available Centre for Disease Control National Survey of Family Growth (NSFG) data set. This was a serial cross-sectional study.

Electrocatalytic Reduction of N Using Metal-Doped Borophene.

Ammonia synthesis is an essential process in chemistry and industry. However, it is limited by the lack of efficient catalysts and high energy costs. Developing highly efficient systems for ammonia synthesis is an important and long-standing challenge.

Properties and Detailed Adsorption of CO by M(dobpdc) with ,-Dimethylethylenediamine Functionalization.

We have systematically investigated the CO adsorption performance and microscopic mechanism of -dimethylethylenediamine (mm-2) appended M(dobpdc) (dobpdc = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate; M = Mg, Sc-Zn) with density functional theory. These calculations show that the mm-2 has strong interactions with the open metal site of these structures via the first amine, and the mm-2 binding energies are generally between 123 and 172 kJ/mol. After the CO is attached, the ammonium carbamate molecule is created by insertion.

Ammonia Synthesis Using Single-Atom Catalysts Based on Two-Dimensional Organometallic Metal Phthalocyanine Monolayers under Ambient Conditions.

We have identified three novel metal phthalocyanine (MPc, M = Mo, Re, and Tc) single-atom catalyst candidates with excellent predicted performance for the production of ammonia from electrocatalytic nitrogen reduction reaction (NRR) through a combination of high-throughput screening and first-principles calculations on a series of 3d, 4d, and 5d transition metals anchored onto extended Pc monolayer catalysts. Analysis of the energy band structures and projected density of states of N-MPc revealed significant orbital hybridization and charge transfer between the adsorbed N and catalyst MPc, which accounts for the high catalytic activity. Among 30 MPc catalysts, MoPc and TcPc monolayers were found to be the most promising new NRR catalysts, as they exhibit excellent stability, low onset potential, and high selectivity.

Formation Mechanism of Ammonium Carbamate for CO Uptake in ,'-Dimethylethylenediamine Grafted M(dobpdc).

The adsorption properties and formation mechanism of ammonium carbamate for CO capture in '-dimethylethylenediamine (mmen) grafted M(dobpdc) (dobpdc = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate; M = Mg, Sc-Zn, except Ni) have been studied via density functional theory (DFT) calculations. We see that the mmen molecule is joined to the metal site via a M-N bond and has hydrogen bonding with neighboring mmen molecules. The binding energies of mmen range from 135.

Elucidation of the Underlying Mechanism of CO Capture by Ethylenediamine-Functionalized M(dobpdc) (M = Mg, Sc-Zn).

We, for the first time, systematically investigated the crystal structures, adsorption properties, and microscopic mechanism of CO capture with ethylenediamine (en)-appended isostructural M(dobpdc) materials (M = Mg, Sc-Zn), using spin polarized density functional theory (DFT) calculations. The binding energies of en range from 142 to 210 kJ/mol. The weakest binding materials are en-Cr(dobpdc) and en-Cu(dobpdc).

Disclosing the microscopic mechanism and adsorption properties of CO capture in N-isopropylethylenediamine appended M(dobpdc) series.

The detailed picture of the microscopic mechanism for CO capture in N-isopropylethylenediamine (i-2) functionalized M(dobpdc) (dobpdc = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate; M = Mg, Sc-Zn) has been determined for the first time via systematic computations with van der Waals (vdW) corrected density functional theory (DFT) methods. The results show that acting as a Lewis base, the i-2 molecule can strongly interact with the acidic open metal sites of M(dobpdc) via its primary amine with binding energies of 132 to 178 kJ mol for different metals. After exposure to gaseous CO, CO is captured by inserting into the metal-N bond.

Intraoperative coagulopathy during cesarean section as an unsuspected initial presentation of COVID-19: a case report.

Background: The world's understanding of COVID-19 continues to evolve as the scientific community discovers unique presentations of this disease. This case report depicts an unexpected intraoperative coagulopathy during a cesarean section in an otherwise asymptomatic patient who was later found to have COVID-19. This case suggests that there may be a higher risk for intrapartum bleeding in the pregnant, largely asymptomatic COVID-positive patient with more abnormal COVID laboratory values.

Adsorption Properties and Microscopic Mechanism of CO Capture in 1,1-Dimethyl-1,2-ethylenediamine-Grafted Metal-Organic Frameworks.

The adsorption properties and microscopic mechanism of CO adsorption in 1,1-dimethyl-1,2-ethylenediamine (dmen) functionalized M(dobpdc) (dobpdc=4,4'-dioxidobiphenyl-3,3'-dicarboxylate; M = Mg, Sc-Zn) have been completely unveiled for the first time via comprehensive investigations based on first-principles density functional theory (DFT) calculations. The results show that for the primary-primary amine, dmen prefers to interact with the open metal site of M(dobpdc) via the end with smaller steric hindrance. The binding energies of dmen with MOFs are in the range of 104-174 kJ/mol.

HIV-positive women with anal high-grade squamous intraepithelial lesions: a study of 153 cases with long-term anogenital surveillance.

Women living with HIV (WLHIV) are at increased risk for human papillomavirus (HPV)-associated anal cancer. Given the "field effect" of HPV pathogenesis, some recommend that anal cancer screening should be limited to WLHIV with prior genital disease. This study aimed to characterize the relationship between anal and genital disease in WLHIV in order to better inform anal cancer screening guidelines.

Efficient electrocatalytic reduction of carbon dioxide by metal-doped β-borophene monolayers.

Electrochemical reduction of CO to value-added chemicals and fuels shows great promise in contributing to reducing the energy crisis and environment problems. This progress has been slowed by a lack of stable, efficient and selective catalysts. In this paper, density functional theory (DFT) was used to study the catalytic performance of the first transition metal series anchored TM-B monolayers as catalysts for electrochemical reduction of CO.

Two-Dimensional Anti-Van't Hoff/Le Bel Array AlB with High Stability, Unique Motif, Triple Dirac Cones, and Superconductivity.

We report the discovery of a rule-breaking two-dimensional aluminum boride (AlB-ptAl-array) nanosheet with a planar tetracoordinate aluminum (ptAl) array in a tetragonal lattice by comprehensive crystal structure search, first-principles calculations, and molecular dynamics simulations. It is a brand new 2D material with a unique motif, high stability, and exotic properties. These anti-van't Hoff/Le Bel ptAl-arrays are arranged in a highly ordered way and connected by two sheets of boron rhomboidal strips above and below the array.

Computational Study of Quasi-2D Liquid State in Free Standing Platinum, Silver, Gold, and Copper Monolayers.

Recently, freestanding atomically thick Fe metal patches up to 10 atoms wide have been fabricated experimentally in tiny pores in graphene. This concept can be extended conceptually to extended freestanding monolayers. We have therefore performed molecular dynamics simulations to evaluate the early melting stages of platinum, silver, gold, and copper freestanding metal monolayers.

The initial stages of melting of graphene between 4000 K and 6000 K.

Graphene and its analogues have some of the highest predicted melting points of any materials. Previous work estimated the melting temperature for freestanding graphene to be a remarkable 4510 K. However, this work relied on theoretical methods that do not accurately account for the role of bond breaking or complex bonding configurations in the melting process.

Halogenated MOF-5 variants show new configuration, tunable band gaps and enhanced optical response in the visible and near infrared.

Inspired by recent experimental fabrication of mono-halogenated versions of Metal-Organic Framework MOF-5 (i.e., X-MOF-5, X = F to I) and some experimentally known fully halogenated MOF compounds, we systematically studied frameworks incorporating full halogenation of the BDC linkers of the prototypical Iso-Reticular Metal-Organic Framework (IRMOF) series, exemplified by MOF-5.

Adding a new dimension to the chemistry of phosphorus and arsenic.

The recently discovered phosphorenes are emerging as promising 2D materials for nanoelectronics. Novel structures and topologies can produce new properties and functionalities, and pave the way for potential new applications. For the first time, we predict two novel highly stable free-standing 2D monolayers of P and As with exotic hypercoordination motifs.

Revealing unusual chemical bonding in planar hyper-coordinate Ni2Ge and quasi-planar Ni2Si two-dimensional crystals.

We discover unusual chemical bonding in a novel planar hyper-coordinate Ni2Ge free-standing 2D monolayer, and also in a nearly planar slightly buckled Ni2Si monolayer. This unusual bonding is revealed by Solid State Adaptive Natural Density Partitioning analysis. This analysis shows that a new type of 2c-2e Ni-Si σ and 3c-2e Ni-Ge-Ni σ bonds stabilize these 2D crystals.

Glitter in a 2D monolayer.

We predict a highly stable and robust atomically thin gold monolayer with a hexagonal close packed lattice stabilized by metallic bonding with contributions from strong relativistic effects and aurophilic interactions. We have shown that the framework of the Au monolayer can survive 10 ps MD annealing simulations up to 1400 K. The framework is also able to survive large motions out of the plane.

The new dimension of silver.

Although significant progress in the fabrication and applications of graphene-like materials has been made, free-standing metal monolayers are extremely rare due to the challenges in fabrication. Furthermore, such structures are often unstable versus 3D close-packed forms. Silver is an important noble metal with many unique properties, and has a wide range of applications in daily life and industry.

Ten new predicted covalent organic frameworks with strong optical response in the visible and near infrared.

We use density functional theory to predict and evaluate 10 novel covalent organic frameworks (COFs), labeled (X4Y)(BDC)3, (X = C/Si; Y = C, Si, Ge, Sn, and Pb), with topology based on metal organic framework isoreticular metal-organic framework (IRMOF-1), but with new elements substituted for the corner atoms. We show that these new materials are stable structures using frequency calculations. For two structures, (C4C and Si4C) molecular dynamics simulations were performed to demonstrate stability of the systems up to 600 K for 10 ps.

Four Decades of the Chemistry of Planar Hypercoordinate Compounds.

The idea of planar tetracoordinate carbon (ptC) was considered implausible for a hundred years after 1874. Examples of ptC were then predicted computationally and realized experimentally. Both electronic and mechanical (e.

Post-anti-van't Hoff-Le Bel motif in atomically thin germanium-copper alloy film.

Using quantum-chemical calculations and reduced dimensionality, we show that the "post-anti-van't Hoff-Le Bel" motif of germanium can be stabilized in a novel two-dimensional (2D) copper-germanium alloy film. This hypercoordinate sheet is the first stable planar hexacoordinate germanium material in 2D space. First principle calculations and molecular dynamics indicate that this Cu2Ge alloy film is a diamagnetic metal, and survives brief 10 ps annealing up to 1200 K.

Two-dimensional Cu2Si monolayer with planar hexacoordinate copper and silicon bonding.

Two-dimensional (2D) materials with planar hypercoordinate motifs are extremely rare due to the difficulty in stabilizing the planar hypercoordinate configurations in extended systems. Furthermore, such exotic motifs are often unstable. We predict a novel Cu2Si 2D monolayer featuring planar hexacoordinate copper and planar hexacoordinate silicon.

A fundamental understanding of catechol and water adsorption on a hydrophilic silica surface: exploring the underwater adhesion mechanism of mussels on an atomic scale.

Mussels have a remarkable ability to bond to solid surfaces under water. From a microscopic perspective, the first step of this process is the adsorption of dopa molecules to the solid surface. In fact, it is the catechol part of the dopa molecule that is interacting with the surface.

Transmission of chimeric HIV by mating in conventional mice: prevention by pre-exposure antiretroviral therapy and reduced susceptibility during estrus.

Heterosexual transmission accounts for the majority of new human immunodeficiency virus (HIV) cases worldwide. The current approach to investigate HIV heterosexual transmission in animals involves application of virus stock to the vaginal surface, a method that does not reproduce the physiological conditions of vaginal intercourse that influence the rate of transmission. We have previously described efficient infection of conventional mice using EcoHIV/NL4-3 and EcoHIV/NDK, chimeric HIV molecular clones constructed to express all HIV structural and regulatory genes except envelope, which is replaced by a rodent-tropic envelope gene.