The Ethics of Clinical Ethics.

The concept ethics defines health care ethics as a professional practice. Yet the meaning of "ethics" is often unclear in the theory and practice of clinical ethics. Clarity on this matter is crucial for understanding the nature of clinical ethics and for debates about the professional identity and proper role of ethicists, the sort of training and skills they should possess, and whether they have ethics expertise.

The Ethical Standard for End-of-Life Decisions for Unrepresented Patients.

There has been increasing awareness of the medical and moral challenges in the care of unrepresented patients: those who cannot make their own medical decisions, do not have any surrogate decision maker, and have not indicated their treatment preferences. Most discussions have focused on procedural questions such as who should make decisions for these patients. An issue that has not gotten enough attention is the ethical standard that should govern medical decision making.

Characteristics and outcomes of prisoners hospitalized due to COVID-19 disease.

Background: Correctional facilities have faced unique challenges during the COVID-19 pandemic. A COVID-19 outbreak was reported in the Federal Medical Center (FMC) in Lexington, Kentucky, a prison for inmates requiring medical and mental care. The main objective of this study was to examine clinical characteristics and outcomes of prisoners vs.

The Ethics of Choosing a Surrogate Decision Maker When Equal-Priority Surrogates Disagree.

When decisionally incapable patients need a surrogate to make medical decisions for them, sometimes the patient has not appointed a healthcare agent and there is intractable disagreement among potential surrogates of equal priority, legal rank, or relation to the patient (e.g., child vs.

Principlism's Balancing Act: Why the Principles of Biomedical Ethics Need a Theory of the Good.

Principlism, the bioethical theory championed by Tom Beauchamp and James Childress, is centered on the four moral principles of beneficence, non-maleficence, respect for autonomy, and justice. Two key processes related to these principles are specification-adding specific content to general principles-and balancing-determining the relative weight of conflicting principles. I argue that both of these processes necessarily involve an appeal to human goods and evils, and therefore require a theory of the good.

The Quality of Life is Not Strained: Disability, Human Nature, Well-Being, and Relationships.

This paper explores the relationship between disability and quality of life and some of its implications for bioethics and healthcare. It focuses on the neglected perfectionist approach that ties well-being to the flourishing of human nature, which provides the strongest support for the common view of disability as a harm. After critiquing the traditional Aristotelian version of perfectionism, which excludes the disabled from flourishing by prioritizing rationalistic goods, I defend a new version that prioritizes the social capacities of human nature and the goods of personal relationship.

Structurally Analogous Degradable Version of Fluorene-Bipyridine Copolymer with Exceptional Selectivity for Large-Diameter Semiconducting Carbon Nanotubes.

Separation of electronically pure, narrowly dispersed, pristine, semiconducting single-walled carbon nanotubes (CNTs) from a heterogeneous as-synthesized mixture is essential for various semiconducting technologies and biomedical applications. Although conjugated polymer wrappers are often utilized to facilitate electronic-type sorting, it is highly desirable to remove organic residues from the resulting devices. We report here the design and synthesis of a mild acid-degradable π-conjugated polyimine polymer, poly[(9,9-di-n-octyl-2,7-fluoren-dinitrilomethine)-alt-co-(6,6'-{2,2'-bipyridyl-dimethine})] (PFO-N-BPy), that is structurally analogous to the commonly used and commercially available poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(6,6'-(2,2'-bipyridine))] (PFO-BPy).

Polymer-Free Electronic-Grade Aligned Semiconducting Carbon Nanotube Array.

Conjugated polymers are used commonly to selectively sort semiconducting carbon nanotubes (S-CNTs) from their metallic counterparts in organic solvents. The polymer-wrapped S-CNTs can be easily processed from organic solvents into arrays of CNTs for scalable device fabrication. Though the conjugated polymers are essential for sorting and device fabrication, it is highly desirable to remove them completely as they limit the electronic properties of the device.

Ultrafast Exciton Hopping Observed in Bare Semiconducting Carbon Nanotube Thin Films with Two-Dimensional White-Light Spectroscopy.

We observe ultrafast energy transfer between bare carbon nanotubes in a thin film using two-dimensional (2D) white-light spectroscopy. Using aqueous two-phase separation, semiconducting carbon nanotubes are purified from their metallic counterparts and condensed into a 10 nm thin film with no residual surfactant. Cross peak intensities put the time scale for energy transfer at <60 fs, and 2D anisotropy measurements determine that energy transfer is most efficient between parallel nanotubes, thus favoring directional energy flow.

Isolation of Pristine Electronics Grade Semiconducting Carbon Nanotubes by Switching the Rigidity of the Wrapping Polymer Backbone on Demand.

Conjugated polymers are among the most selective carbon nanotube sorting agents discovered and enable the isolation of ultrahigh purity semiconducting singled-walled carbon nanotubes (s-SWCNTs) from heterogeneous mixtures that contain problematic metallic nanotubes. The strong selectivity though highly desirable for sorting, also leads to irreversible adsorption of the polymer on the s-SWCNTs, limiting their electronic and optoelectronic properties. We demonstrate how changes in polymer backbone rigidity can trigger its release from the nanotube surface.

Experimental Measurement of the Binding Configuration and Coverage of Chirality-Sorting Polyfluorenes on Carbon Nanotubes.

Poly(9,9-dioctylfluorene-2,7-diyl) (PFO) exhibits exceptional (n,m) chirality and electronic-type selectivity for near-armchair semiconducting carbon nanotubes. To better understand and control the factors governing this behavior, we experimentally determine the surface coverage and binding configuration of PFO on nanotubes in solution using photoluminescence energy transfer and anisotropy measurements. The coverage increases with PFO concentration in solution, following Langmuir-isotherm adsorption behavior with cooperativity.

Polyfluorene-sorted, carbon nanotube array field-effect transistors with increased current density and high on/off ratio.

Challenges in eliminating metallic from semiconducting single-walled carbon nanotubes (SWCNTs) and in controlling their alignment have limited the development of high-performance SWCNT-based field-effect transistors (FETs). We recently pioneered an approach for depositing aligned arrays of ultra-high-purity semiconducting SWCNTs, isolated using polyfluorene derivatives, called dose-controlled floating evaporative self-assembly. Here, we tailor FETs fabricated from these arrays to achieve on-conductance (G(on)) per width and an on-off ratio (G(on)/G(off)) of 261 μS/μm and 2 × 10(5), respectively, for a channel length (L(ch)) of 240 nm and 116 μS/μm and 1 × 10(6), respectively, for an L(ch) of 1 μm.