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Current evidence and applications of photodynamic therapy in dermatology
In photodynamic therapy (PDT) a photosensitizer – a molecule that is activated by light – is administered and exposed to a light source. This leads both to destruction of cells targeted by the particular type of photosensitizer, and immunomodulation. Given the ease with which photosensitizers and light can be delivered to the skin, it should come as no surprise that PDT is an increasingly utilized therapeutic in dermatology. PDT is used commonly to treat precancerous cells, sun-damaged skin, and acne. It has reportedly also been used to treat other conditions including inflammatory disorders and cutaneous infections. This review discusses the principles behind how PDT is used in dermatology, as well as evidence for current applications of PDT
Tracing the trophic fate of aquafeed macronutrients with carbon isotope ratios of Amino Acids
To meet future seafood demands, ingredients derived from algae and other novel and sustainable sources are increasingly being tested and used as replacers to traditional aquafeed ingredients. Algal ingredients in particular are being promoted for their sustainability and their additional functional attributes in farmed aquatic animals. Test on algal supplemented aquafeeds typically focus on a suite of immunological and physiological indicators along with fish growth performance or muscle quality. However, to optimize the replacement of fish meal with algal derived ingredients, it is crucial to understand the metabolic fate in the algal macronutrients (carbohydrates, fats, and proteins), and their nutritional interactions with other ingredients after ingestion. Here, we assess the potential of using the emerging technology- stable carbon isotope (δ13C) analysis of single amino acids (AAs) as a nutritional biomarker in aquaculture. Applications of δ13CAA-based approaches in feeding trials show promise in closing the knowledge gap in terms of understanding how fish and other aquaculture taxa assimilate and metabolize algal derived macronutrients. Source diagnostic δ13C fingerprints among the essential AAs can trace the protein origins to broad phylogenetic groups such as red macroalgae, brown macroalgae, bacteria, and terrestrial plants. Among the non-essential AAs, δ13C patterns have the potential to inform about metabolic routing and utilization of dietary lipids and carbohydrates. Despite the potential of δ13CAA as a nutritional biomarker, the few applications to date in fish feeding trials warrant further development and implementation of δ13CAA-based approaches to improve understanding of protein origins and macronutrient metabolic routing.Introduction Amino acid abbreviations Analitical considerations Digestive physiology and isotope effects Inferring diet and nutrition from amino acid 13C values - Essential Amino Acids - Non-essential Amino Acids Tracing aquafeed macronutrients with 13CAA Outlook and perpectives Materials and methods - Statistical Method
Testing identifying assumptions in fuzzy regression discontinuity designs
We propose a new specification test for assessing the validity of fuzzy regression discontinuity designs (FRD-validity). We derive a new set of testable implications, characterized by a set of
inequality restrictions on the joint distribution of observed outcomes and treatment status at the cut-off.
We show that this new characterization exploits all the information in the data useful for detecting
violations of FRD-validity. Our approach differs from, and complements existing approaches that test
continuity of the distributions of running variables and baseline covariates at the cut-off since ours
focuses on the distribution of the observed outcome and treatment status. We show that the proposed
test has appealing statistical properties. It controls size in large sample uniformly over a large class of
distributions, is consistent against all fixed alternatives, and has non-trivial power against some local
alternatives. We apply our test to evaluate the validity of two FRD designs. The test does not reject the
FRD-validity in the class size design studied by Angrist and Lavy (1999) and rejects in the insurance
subsidy design for poor households in Colombia studied by Miller, Pinto, and Vera-Hernández (2013)
for some outcome variables, while existing density tests suggest the opposite in each of the cases
Testing Identifying Assumptions in Fuzzy Regression Discontinuity Designs
We propose a new specification test for assessing the validity of fuzzy regression discontinuity designs (FRD-validity). We derive a new set of testable implications, characterized by a set of inequality restrictions on the joint distribution of observed outcomes and treatment status at the cut-off. We show that this new characterization exploits all of the information in the data that is useful for detecting violations of FRD-validity. Our approach differs from and complements existing approaches that test continuity of the distributions of running variables and baseline covariates at the cut-off in that we focus on the distribution of the observed outcome and treatment status. We show that the proposed test has appealing statistical properties. It controls size in a large sample setting uniformly over a large class of data generating processes, is consistent against all fixed alternatives, and has non-trivial power against some local alternatives. We apply our test to evaluate the validity of two FRD designs. The test does not reject FRD-validity in the class size design studied by Angrist and Lavy (1999) but rejects it in the insurance subsidy design for poor households in Colombia studied by Miller, Pinto, and Vera-Hernández (2013) for some outcome variables. Existing density continuity tests suggest the opposite in each of the two cases
Energy transfer, pressure tensor and heating of kinetic plasma
Kinetic plasma turbulence cascade spans multiple scales ranging from
macroscopic fluid flow to sub-electron scales. Mechanisms that dissipate large
scale energy, terminate the inertial range cascade and convert kinetic energy
into heat are hotly debated. Here we revisit these puzzles using fully kinetic
simulation. By performing scale-dependent spatial filtering on the Vlasov
equation, we extract information at prescribed scales and introduce several
energy transfer functions. This approach allows highly inhomogeneous energy
cascade to be quantified as it proceeds down to kinetic scales. The pressure
work, , can
trigger a channel of the energy conversion between fluid flow and random
motions, which is a collision-free generalization of the viscous dissipation in
collisional fluid. Both the energy transfer and the pressure work are strongly
correlated with velocity gradients.Comment: 28 pages, 10 figure
Symmetries of SU(2) Skyrmion in Hamiltonian and Lagrangian approaches
We apply the Batalin-Fradkin-Tyutin (BFT) method to the SU(2) Skyrmion to
study the full symmetry structure of the model at the first class Hamiltonian
level. On the other hand, we also analyze the symmetry structure of the action
having the WZ term, which corresponds to this Hamiltonian, in the framework of
the Lagrangian approach. Furthermore, following the BFV formalism we derive the
BRST invariant gauge fixed Lagrangian from the above extended action.Comment: 14 pages, final revised version, to appear in Mod. Phys. Lett.
Damage-free single-mode transmission of deep-UV light in hollow-core PCF
Transmission of UV light with high beam quality and pointing stability is
desirable for many experiments in atomic, molecular and optical physics. In
particular, laser cooling and coherent manipulation of trapped ions with
transitions in the UV require stable, single-mode light delivery. Transmitting
even ~2 mW CW light at 280 nm through silica solid-core fibers has previously
been found to cause transmission degradation after just a few hours due to
optical damage. We show that photonic crystal fiber of the kagom\'e type can be
used for effectively single-mode transmission with acceptable loss and bending
sensitivity. No transmission degradation was observed even after >100 hours of
operation with 15 mW CW input power. In addition it is shown that
implementation of the fiber in a trapped ion experiment significantly increases
the coherence times of the internal state transfer due to an increase in beam
pointing stability
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