Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 12 de 12
Filter
1.
Chin Med Cult ; 7(1): 72-76, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38559905

ABSTRACT

Huang Di Nei Jing (《》The Yellow Emperor's Inner Classic) has been the source text of Chinese medicine knowledge and innovation for over two thousand years. Despite this key relevance, many of its ideas and practices have proven difficult to understand and implement fully into clinical practice. Cultural and language differences can be compounded with these challenges but may also present new opportunities for advancement and insight when studied by researchers outside of the originating culture. This article introduces the method of Classical-Text Archaeology and delves into the author's two-decade journey of researching this text, with a discussion on cultural differences and issues of medical scholarship.

2.
J Phys Chem B ; 127(15): 3416-3430, 2023 Apr 20.
Article in English | MEDLINE | ID: mdl-37026896

ABSTRACT

A refined numerical model for the evaporation and transport of droplets of binary solutions is introduced. Benchmarking is performed against other models found in the literature and experimental measurements of both electrodynamically trapped and freefalling droplets. The model presented represents the microphysical behavior of solutions droplets in the continuum and transition regimes, accounting for the unique hygroscopic behavior of different solutions, including the Fuchs-Sutugin and Cunningham slip correction factors, and accounting for the Kelvin effect. Simulations of pure water evaporation are experimentally validated for temperatures between 290 K and 298 K and between relative humidity values of approximately 0% and 85%. Measurements and simulations of the spatial trajectories and evaporative behavior of aqueous sodium chloride droplets are compared for relative humidity values between 0 and 40%. Simulations are shown to represent experimental data within experimental uncertainty in initial conditions. Calculations of a time-dependent Péclet number, including the temperature dependence of solute diffusion, are related to morphologies of sodium chloride particles dried at different rates. For sodium chloride solutions, dried particles are composed of collections of reproducibly shaped crystals, with higher evaporation rates resulting in higher numbers of crystals, which are smaller.

3.
Viruses ; 14(9)2022 08 24.
Article in English | MEDLINE | ID: mdl-36146663

ABSTRACT

Respiratory pathogens can be spread though the transmission of aerosolised expiratory secretions in the form of droplets or particulates. Understanding the fundamental aerosol parameters that govern how such pathogens survive whilst airborne is essential to understanding and developing methods of restricting their dissemination. Pathogen viability measurements made using Controlled Electrodynamic Levitation and Extraction of Bioaerosol onto Substrate (CELEBS) in tandem with a comparative kinetics electrodynamic balance (CKEDB) measurements allow for a direct comparison between viral viability and evaporation kinetics of the aerosol with a time resolution of seconds. Here, we report the airborne survival of mouse hepatitis virus (MHV) and determine a comparable loss of infectivity in the aerosol phase to our previous observations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Through the addition of clinically relevant concentrations of mucin to the bioaerosol, there is a transient mitigation of the loss of viral infectivity at 40% RH. Increased concentrations of mucin promoted heterogenous phase change during aerosol evaporation, characterised as the formation of inclusions within the host droplet. This research demonstrates the role of mucus in the aerosol phase and its influence on short-term airborne viral stability.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Mice , Microbial Viability , Mucins , Respiratory Aerosols and Droplets
5.
Chem Commun (Camb) ; 57(13): 1663-1666, 2021 Feb 14.
Article in English | MEDLINE | ID: mdl-33463642

ABSTRACT

ortho-Silylaryl triflate precursors (oSATs) have been responsible for many recent advances in aryne chemistry and are most commonly accessed from the corresponding 2-bromophenol. A retro-Brook O- to C-silyl transfer is a key step in this synthesis but not all aromatic species are amenable to the transformation, with no functionalized bisbenzyne oSATs reported. Simple Hückel models are presented which show that the calculated aromaticity at the brominated position is an accurate predictor of successful retro-Brook reaction, validated synthetically by a new success and a predicted failure. From this, the synthesis of a novel difunctionalized bisaryne precursor has been tested, requiring different approaches to install the two C-silyl groups. The first successful use of a disubstituted o-silylaryl sulfonate bisbenzyne precursor in Diels-Alder reactions is then shown.

6.
Acc Chem Res ; 52(7): 1834-1843, 2019 Jul 16.
Article in English | MEDLINE | ID: mdl-31282645

ABSTRACT

Fullerene (C60), a π-conjugated cage molecule consisting of 60 sp2-hybridized carbon atoms that are arranged into perfect icosahedral symmetry, is one of the most extensively studied nanocarbon materials by virtue of its characteristic spherical structure, fascinating optoelectronic properties, and widespread applications in material science. To implement practical applications, C60 is generally used as a building motif to assemble into various ordered superstructures. Unlike the controllable face-to-face π-π interactions of planar π-conjugated molecules, the π-π interactions between the three-dimensional spherical C60 units are random and directionless, which generally lead to complicated aggregated structures and unpredictable properties. The primary target of our research is to produce a robust design strategy for functional C60 materials, by which the single C60 molecules can be engineered into desirable self-organized architectures with optimized functions. To this end, we focused on alkylated fullerene (alk-C60) derivatives, a simple molecular system whose two components, alkyl chains and C60, exhibit both hydrophobicity yet different affinities to organic solvents. As a result, the alk-C60 derivatives present an unusual "hydrophobic amphiphile" system. Through systematic tuning of the substitution pattern of a series of alkyl side chains (number, length, branching, and substitution position) and external experimental conditions, the factors influencing alk-C60 self-assembly behaviors were determined. In addition, the feasibility of forming hybrid coassemblies with alk-C60 and other nanocarbon materials was demonstrated. By taking full advantage of the hydrophobic nature and active optoelectronic properties of these self- or hybrid-assemblies, various superhydrophobic materials and/or optoelectronic devices were developed. However, supported only by weak noncovalent interactions, these ordered superstructures are intrinsically fragile under various external stimuli. To improve the structural stability and achieve consistent optoelectronic performance of these novel materials, we strengthened the ordered structures via metallization and plasticization. Both approaches gave rise to robust and endurable materials with functions inherited from the pristine assemblies but at the cost of their former softness and facile processability. Thereafter, we focused on amorphous materials in view of their consistent and predictable optoelectronic properties that are independent of their geometry and physical environment. Unexpectedly, the amorphous materials obtained were liquids at room temperature, whose excellent deformability might enable applications in flexible/wearable optoelectronic devices. However, the lack of sufficient molecular order impaired their optoelectronic performance. To address this, we devised a straightforward strategy toward the directed ordered self-assembly of the alk-C60 liquids by adding molecular cofactors (n-alkanes or C60) into the liquids. Using this strategy, the balance between intermolecular order and material softness can be readily adjusted to meet different application requirements. Through iterative refinements to our novel alk-C60 system, we have demonstrated its power in generating numerous self-assembled, hybrid-assembled, and nonassembled materials toward versatile applications. We believe such a comprehensive description of these alk-C60-based functional materials provides deep insights into these still-evolving materials, which will underpin more advanced applications in near future.

7.
Angew Chem Int Ed Engl ; 55(40): 12488-93, 2016 09 26.
Article in English | MEDLINE | ID: mdl-27600208

ABSTRACT

In this proof-of-concept study, an active-template coupling is used to demonstrate a novel kinetic self-sorting process. This process iteratively increases the yield of the target heterocircuit [3]rotaxane product at the expense of other threaded species.

8.
Exp Mol Pathol ; 99(2): 335-40, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26116154

ABSTRACT

BACKGROUND: Human papillomavirus (HPV)-positive oropharyngeal cancer is associated with improved survival and treatment response as compared to HPV-negative cancers. P16 overexpression is widely accepted as a surrogate marker for HPV positivity. METHODS: A total of 92 serum samples from 75 head and neck squamous cell carcinoma (HNSCC) patients were examined for HPV16 and 18 E7 antibodies by ELISA. Available tissue was tested for HPV-DNA by PCR, and p16 immunohistochemistry was obtained from a deidentified database. RESULTS: Of 75 HNSCC patients, 25 were HPV E7 seropositive. Seropositivity was strongly associated with cancers of the oropharynx, and correlated with positive p16 immunohistochemistry (IHC) and HPV-DNA. Post-treatment serum was available in a limited subset of patients, revealing a decrease in antibody titers following response to treatment. CONCLUSIONS: HPV E7 seropositivity correlated with positive tumor HPV-DNA and p16 expression, and was strongly associated with cancers of the oropharynx. E7 serology warrants further study as a potential biomarker in HPV-positive HNSCC.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Head and Neck Neoplasms/metabolism , Papillomavirus E7 Proteins/blood , Papillomavirus Infections/virology , Adult , Aged , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/virology , DNA, Viral/genetics , Enzyme-Linked Immunosorbent Assay , Female , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/virology , Human papillomavirus 16/genetics , Human papillomavirus 16/isolation & purification , Humans , Immunoenzyme Techniques , Male , Middle Aged , Neoplasm Staging , Papillomavirus Infections/metabolism , Papillomavirus Infections/pathology , Polymerase Chain Reaction , Prognosis , Seroepidemiologic Studies
9.
Chem Sci ; 6(4): 2398-2404, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-29308153

ABSTRACT

We recently identified competitive formation of doubly interlocked [3]rotaxanes as the origin of the non-linear variation in yield of [2]rotaxane with macrocycle size in the bipyridine-mediated AT-CuAAC reaction. Selection of reaction conditions gave [2]rotaxanes in essentially quantitative yield in all cases and hard to access doubly threaded [3]rotaxanes in up to 50% yield in a single, four component coupling. Based on the effect of macrocycle structure on the reaction outcome we propose a detailed mechanism of [3]rotaxane formation.

10.
Chem Commun (Camb) ; 50(40): 5128-42, 2014 May 25.
Article in English | MEDLINE | ID: mdl-24434901

ABSTRACT

Research on mechanically interlocked molecules has advanced substantially over the last five decades. A large proportion of the published work focusses on the synthesis of these challenging targets, and the subsequent control of the relative position of the covalent sub-components, to generate novel molecular devices and machines. In this Feature Article we instead review some of the less discussed consequences of mechanical bonding for the chemical behaviour of catenanes and rotaxanes, and their application in synthesis, including striking recent examples of molecular machines which carry out complex synthetic tasks.

11.
J Dent Educ ; 67(11): 1234-42, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14650505

ABSTRACT

Learners gain additional value from community-based education when they are guided through a reflective process. The purpose of this article is to describe how structured reflection assignments and methods are incorporated in the University of North Carolina School of Dentistry's community-based DISC (Dentistry in Service to Communities) program. The following strategies are described as ways to enrich community-based learning experiences for dental students: photographic documentation; written narratives; critical incident reports; and mentored post-experiential small group discussions. Fieldwork and course-related examples are drawn from community-based dental experiences to illustrate how reflective teaching approaches can enhance student learning. A directed process of reflection is suggested as a way to increase the impact of the community learning experience.


Subject(s)
Clinical Competence , Community Dentistry/education , Education, Dental/methods , Problem-Based Learning/methods , Self-Assessment , Students, Dental/psychology , Attitude of Health Personnel , Humans , Program Evaluation , United States
12.
Nurs Outlook ; 51(5): 227-32, 2003.
Article in English | MEDLINE | ID: mdl-14569229

ABSTRACT

Although faculty members often come to a university school of nursing with little or no experience in teaching, research, or other forms of scholarship, few schools of nursing have a comprehensive, formalized faculty development program. In considering the need to find and retain the best faculty in this competitive market, the University of North Carolina at Chapel Hill School of Nursing appointed a task force to develop a formal faculty development program for the School. After reviewing the literature and contacting 24 schools of nursing, the task force concluded that most do not offer a systematic approach to faculty development. The task force developed and distributed a needs assessment and received responses from 53% of the faculty. Based on the needs assessment the task force made eight recommendations to the faculty for an ongoing, comprehensive faculty development program.


Subject(s)
Education, Nursing , Faculty, Nursing/standards , Professional Competence , Curriculum , Humans , Needs Assessment , Schools, Nursing , Workforce
SELECTION OF CITATIONS
SEARCH DETAIL
...