59 research outputs found
Complexity measures and uncertainty relations of the high-dimensional harmonic and hydrogenic systems
In this work we find that not only the Heisenberg-like uncertainty products
and the R\'enyi-entropy-based uncertainty sum have the same first-order values
for all the quantum states of the -dimensional hydrogenic and
oscillator-like systems, respectively, in the pseudoclassical ()
limit but a similar phenomenon also happens for both the
Fisher-information-based uncertainty product and the Shannon-entropy-based
uncertainty sum, as well as for the Cr\'amer-Rao and Fisher-Shannon
complexities. Moreover, we show that the LMC (L\'opez-Ruiz-Mancini-Calvet) and
LMC-R\'enyi complexity measures capture the hydrogenic-harmonic difference in
the high dimensional limit already at first order
Synthesis of Tetrafluorinated Aromatic Amino Acids with Distinct Signatures in <sup>19</sup>F NMR
Fluorinated amino acids serve as powerful tools in protein chemistry. We synthesized a series of <i>para</i>-substituted tetrafluorophenylalanines via the regioselective S<sub>NAr</sub> chemistry of the commercially available pentafluorophenylalanine Boc-Z. These novel unnatural amino acids display distinct <sup>19</sup>F NMR signatures, making them powerful tools for analyzing protein–membrane interactions with NMR spectroscopy
Fast Diazaborine Formation of Semicarbazide Enables Facile Labeling of Bacterial Pathogens
Bioorthogonal conjugation
chemistry has enabled the development
of tools for the interrogation of complex biological systems. Although
a number of bioorthogonal reactions have been documented in literature,
they are less ideal for one or several reasons including slow kinetics,
low stability of the conjugated product, requirement of toxic catalysts,
and side reactions with unintended biomolecules. Herein we report
a fast (>10<sup>3</sup> M<sup>–1</sup> s<sup>–1</sup>) and bioorthogonal conjugation reaction that joins semicarbazide
to an aryl ketone or aldehyde with an <i>ortho</i>-boronic
acid substituent. The boronic acid moiety greatly accelerates the
initial formation of a semicarbazone conjugate, which rearranges into
a stable diazaborine. The diazaborine formation can be performed in
blood serum or cell lysates with minimal interference from biomolecules.
We further demonstrate that application of this conjugation chemistry
enables facile labeling of bacteria. A synthetic amino acid D-AB3,
which presents a 2-acetylphenylboronic acid moiety as its side chain,
was found to incorporate into several bacterial species through cell
wall remodeling, with particularly high efficiency for <i>Escherichia
coli</i>. Subsequent D-AB3 conjugation to a fluorophore-labeled
semicarbazide allows robust detection of this bacterial pathogen in
blood serum
Fast Diazaborine Formation of Semicarbazide Enables Facile Labeling of Bacterial Pathogens
Bioorthogonal conjugation
chemistry has enabled the development
of tools for the interrogation of complex biological systems. Although
a number of bioorthogonal reactions have been documented in literature,
they are less ideal for one or several reasons including slow kinetics,
low stability of the conjugated product, requirement of toxic catalysts,
and side reactions with unintended biomolecules. Herein we report
a fast (>10<sup>3</sup> M<sup>–1</sup> s<sup>–1</sup>) and bioorthogonal conjugation reaction that joins semicarbazide
to an aryl ketone or aldehyde with an <i>ortho</i>-boronic
acid substituent. The boronic acid moiety greatly accelerates the
initial formation of a semicarbazone conjugate, which rearranges into
a stable diazaborine. The diazaborine formation can be performed in
blood serum or cell lysates with minimal interference from biomolecules.
We further demonstrate that application of this conjugation chemistry
enables facile labeling of bacteria. A synthetic amino acid D-AB3,
which presents a 2-acetylphenylboronic acid moiety as its side chain,
was found to incorporate into several bacterial species through cell
wall remodeling, with particularly high efficiency for <i>Escherichia
coli</i>. Subsequent D-AB3 conjugation to a fluorophore-labeled
semicarbazide allows robust detection of this bacterial pathogen in
blood serum
Dynamic Formation of Imidazolidino Boronate Enables Design of Cysteine-Responsive Peptides
We
describe the dynamic and chemoselective conjugation between
2-formylphenylboronic acid and l-2,3-diaminopropionic acid
yielding an imidazolidino boronate (IzB) complex. The IzB complex
formation readily proceeds in biological milieu with little interference
by common biomolecules except cysteine. We demonstrate the potential
of this reversible conjugation for biological applications by creating
“smart” peptides that specifically respond to cysteine
in complex biological media. Specifically, the design and characterization
of a fluorogenic sensor of cysteine is described
Photoinduced Oscillations and Pulse Waves in the Hydrogen Peroxide–Sulfite–Ferrocyanide Reaction
The
hydrogen peroxide–sulfite–ferrocyanide reaction
shows excellent photosensitivity under pulse light illumination, which
can be used to efficiently control the spatiotemporal dynamics of
the nonlinear chemical system. Here, we numerically simulated the
photoinduced pH oscillations by integrating two models that describe
the oscillatory and photosensitive behaviors, respectively. A dynamic
transition from the low-pH steady state to oscillations can be obtained
using light illumination. In accordance with the simulation results,
oscillatory dynamics was experimentally obtained under light illumination
through excitation of a low-pH steady state. In the reaction–diffusion
medium, corresponding multiple pulse waves were observed under suitable
acid concentration and illumination conditions. Hence, light illumination
can be efficiently employed to tune pattern formation in pH dynamic
systems. Especially, the observation indicates that the local oscillations
and pulse waves were promoted by diffusion in the gel reactor when
comparing with dynamics in a homogeneous system
Photoinduced Oscillations and Pulse Waves in the Hydrogen Peroxide–Sulfite–Ferrocyanide Reaction
The
hydrogen peroxide–sulfite–ferrocyanide reaction
shows excellent photosensitivity under pulse light illumination, which
can be used to efficiently control the spatiotemporal dynamics of
the nonlinear chemical system. Here, we numerically simulated the
photoinduced pH oscillations by integrating two models that describe
the oscillatory and photosensitive behaviors, respectively. A dynamic
transition from the low-pH steady state to oscillations can be obtained
using light illumination. In accordance with the simulation results,
oscillatory dynamics was experimentally obtained under light illumination
through excitation of a low-pH steady state. In the reaction–diffusion
medium, corresponding multiple pulse waves were observed under suitable
acid concentration and illumination conditions. Hence, light illumination
can be efficiently employed to tune pattern formation in pH dynamic
systems. Especially, the observation indicates that the local oscillations
and pulse waves were promoted by diffusion in the gel reactor when
comparing with dynamics in a homogeneous system
An equity analysis of health examination service utilization by women from underdeveloped areas in western China
<div><p>Objective</p><p>This study sought to examine the sources of inequity in health examination service utilization by women from underdeveloped areas in western China.</p><p>Methods</p><p>Based on data from the 5<sup>th</sup> National Health Service Survey in Shaanxi province, women’s utilization of health examination services was examined according to gynecological, cervical smear, and breast examination rates. The equity of health examination service utilization by 15- to 64-year-old women and the factors contributing to inequity were determined using the health concentration index, decomposition of the concentration index, and the horizontal inequity index.</p><p>Results</p><p>The examination rates for gynecological, cervical smear, and breast exams for 15- to 64-year-old women in Shaanxi province were 40.61%, 27.08%, and 24.59%, respectively. The horizontal inequity indices of gynecological, cervical smear, and breast examination rates were 0.0480, 0.0423, and 0.0764, respectively, and each examination rate was higher for wealthy individuals. The contribution rates of economic status to the inequalities in gynecological, cervical smear, and breast examination rates were 65.80%, 74.31%, and 56.49%, respectively. The contribution rates of educational status to the inequalities in gynecological, cervical smear, and breast examination rates were 21.01%, 14.83% and 30.00%, respectively. The contribution rates of age to the inequalities in gynecological, cervical smear, and breast examination rates were 25.77%, 26.55%, and 18.40%, respectively.</p><p>Conclusions</p><p>Women’s health examination rates differed between populations with different socio-demographic characteristics. There is pro-wealth inequality in each examination rate. This study found that financial status, age, and education level were the main reasons for the unequal utilization of health examination services.</p></div
Measures of poverty gross and net of health payments and after compensation for hospital admission insured.
<p>Measures of poverty gross and net of health payments and after compensation for hospital admission insured.</p
Effect of UEBMI on health services utilisation by the level of hospitals.
<p>Note: Chi-square test was used to testify the significant difference.</p
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