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1.
Open Forum Infect Dis ; 10(8): ofad428, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37663091

RESUMO

The Penn Medicine COVID-19 Therapeutics Committee-an interspecialty, clinician-pharmacist, and specialist-front line primary care collaboration-has served as a forum for rapid evidence review and the production of dynamic practice recommendations during the 3-year coronavirus disease 2019 public health emergency. We describe the process by which the committee went about its work and how it navigated specific challenging scenarios. Our target audiences are clinicians, hospital leaders, public health officials, and researchers invested in preparedness for inevitable future threats. Our objectives are to discuss the logistics and challenges of forming an effective committee, undertaking a rapid evidence review process, aligning evidence-based guidelines with operational realities, and iteratively revising recommendations in response to changing pandemic data. We specifically discuss the arc of evidence for corticosteroids; the noble beginnings and dangerous misinformation end of hydroxychloroquine and ivermectin; monoclonal antibodies and emerging viral variants; and patient screening and safety processes for tocilizumab, baricitinib, and nirmatrelvir-ritonavir.

2.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 1): 33-37, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36628363

RESUMO

Two novel LiCl·DMSO polymer structures were created by combining dry LiCl salt with dimethyl sulfoxide (DMSO), namely, catena-poly[[chlorido-lithium(I)]-µ-(dimethyl sulfoxide)-κ2 O:O-[chlorido-lithium(I)]-di-µ-(dimethyl sulfoxide)-κ4 O:O], [Li2Cl2(C2H6OS)3] n , and catena-poly[lithium(I)-µ-chlorido-µ-(dimethyl sulfoxide)-κ2 O:O], [LiCl(C2H6OS)] n . The initial synthesized phase had very small block-shaped crystals (<0.08 mm) with monoclinic symmetry and a 2 LiCl: 3 DMSO ratio. As the solution evaporated, a second phase formed with a plate-shaped crystal morphology. After about 20 minutes, large (>0.20 mm) octa-hedron-shaped crystals formed. The plate crystals and the octa-hedron crystals are the same tetra-gonal structure with a 1 LiCl: 1 DMSO ratio. These structures are reported and compared to other known LiCl·solvent compounds.

3.
Infect Control Hosp Epidemiol ; 42(1): 93-95, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873345

RESUMO

A cross-sectional survey study of inpatient prescribers in a university health system was performed to assess the importance they place on different clinical risk factors when making empiric antibiotic decisions. Our findings show that these clinical risk factors were weighted differently based on the clinical scenario and the type of prescriber.


Assuntos
Antibacterianos , Padrões de Prática Médica , Antibacterianos/uso terapêutico , Estudos Transversais , Humanos , Inquéritos e Questionários
4.
J Am Chem Soc ; 133(41): 16486-94, 2011 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-21879723

RESUMO

One of the challenges in organic systems with semiconducting function is the achievement of molecular orientation over large scales. We report here on the use of self-assembly kinetics to control long-range orientation of a quarterthiophene derivative designed to combine intermolecular π-π stacking and hydrogen bonding among amide groups. Assembly of these molecules in the solution phase is prevented by the hydrogen-bond-accepting solvent tetrahydrofuran, whereas formation of H-aggregates is facilitated in toluene. Rapid evaporation of solvent in a solution of the quarterthiophene in a 2:1:1 mixture of 1,4-dioxane/tetrahydrofuran/toluene leads to self-assembly of kinetically trapped mats of bundled fibers. In great contrast, slow drying in a toluene atmosphere leads to the homogeneous nucleation and growth of ordered structures shaped as rhombohedra or hexagonal prisms depending on concentration. Furthermore, exceedingly slow delivery of toluene from a high molecular weight polymer solution into the system through a porous aluminum oxide membrane results in the growth of highly oriented hexagonal prisms perpendicular to the interface. The amide groups of the compound likely adsorb onto the polar aluminum oxide surface and direct the self-assembly pathway toward heterogeneous nucleation and growth to form hexagonal prisms. We propose that the oriented prismatic polymorph results from the synergy of surface interactions rooted in hydrogen bonding on the solid membrane and the slow kinetics of self-assembly. These observations demonstrate how self-assembly conditions can be used to guide the supramolecular energy landscape to generate vastly different structures. These fundamental principles allowed us to grow oriented prismatic assemblies on transparent indium-doped tin oxide electrodes, which are of interest in organic electronics.


Assuntos
Membranas Artificiais , Polímeros/química , Polímeros/síntese química , Tiofenos/química , Tiofenos/síntese química , Óxido de Alumínio/química , Dioxanos/química , Furanos/química , Ligação de Hidrogênio , Cinética , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Tolueno/química
5.
ACS Nano ; 5(1): 565-73, 2011 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21142087

RESUMO

One of the challenges in the synthesis of hybrid materials with nanoscale structure is to precisely control morphology across length scales. Using a one-step electrodeposition process on indium tin oxide (ITO) substrates followed by annealing, we report here the preparation of materials with preferentially oriented lamellar domains of electron donor surfactants and the semiconductor ZnO. We found that either increasing the concentration of surfactant or the water to dimethyl sulfoxide ratio of solutions used resulted in the suppression of bloomlike morphologies and enhanced the density of periodic domains on ITO substrates. Furthermore, by modifying the surface of the ITO substrate with the conductive polymer blend poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), we were able to alter the orientation of these electrodeposited lamellar domains to be perpendicular to the substrate. The long-range orientation achieved was characterized by 2D grazing incidence small-angle X-ray scattering. This high degree of orientation in electronically active hybrids with alternating nanoscale p-type and n-type domains is of potential interest in photovoltaics or thermoelectric materials.


Assuntos
Galvanoplastia/métodos , Compostos Inorgânicos/química , Nanoestruturas/química , Compostos Orgânicos/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Polímeros/química , Poliestirenos/química , Pirenos/química , Espalhamento a Baixo Ângulo , Semicondutores , Compostos de Estanho/química , Difração de Raios X , Óxido de Zinco/química
6.
Nat Mater ; 8(1): 68-75, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19060890

RESUMO

Highly ordered nanostructured organic/inorganic hybrids offer chemical tunability, novel functionalities and enhanced performance over their individual components. Hybrids of complementary p-type organic and n-type inorganic components have attracted interest in optoelectronics, where high-efficiency devices with minimal cost are desired. We demonstrate here self-assembly of a lamellar hybrid containing periodic and alternating 1-nm-thick sheets of polycrystalline ZnO separated by 2-3 nm layers of conjugated molecules, directly onto an electrode. Initially the electrodeposited inorganic is Zn(OH)(2), but pi-pi interactions among conjugated molecules stabilize synergistically the periodic nanostructure as it converts to ZnO at 150 degrees C. As photoconductors, normalized detectivities (D(*)) greater than 2x10(10) Jones, photocurrent gains of 120 at 1.2 V microm(-1) and dynamic ranges greater than 60 dB are observed on selective excitation of the organic. These are among the highest values measured for organic, hybrid and amorphous silicon, making them technologically competitive as low-power, wavelength-tunable, flexible and environmentally benign photoconductors.

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