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1.
Entropy (Basel) ; 24(5)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35626627

RESUMO

The authors wish to make the following correction to this paper [...].

2.
Ann Med ; 54(1): 666-673, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35243932

RESUMO

Neurotrophic keratopathy (NK), or neurotrophic keratitis, is a degenerative condition that results from decreased innervation to the cornea. The cornea is innervated by the ophthalmic branch of the trigeminal nerve. Neurotrophic keratopathy is most commonly caused by herpes keratitis however, any condition that disrupts the normal corneal innervation can cause NK. Neurotrophic keratopathy is a clinical diagnosis and is classified into three stages based on the disease severity. Stage 1 has mild epithelial defects, such as punctate keratopathy, stage 2 disease has persistent epithelial defects, and stage 3 is defined by the presence of ulcers. Current treatment modalities consist of medical and surgical options. Stage 1 is treated with lubrication through artificial tears, eyelid taping, and punctal plug/cautery. Stage 2 treatment can involve therapeutic contact lenses, topical autologous or allogenic serum, tarsorrhaphy, botulinum toxin injections, and possibly anti-inflammatory medications. Stage 3 disease may require human nerve growth factor, amniotic membrane transplantation, conjunctival flap, or corneal neurotization. New therapies, such as matrix regenerating therapy, plasma rich in growth factors, Thymosin ß4, Substance P/Insulin like growth factor-1, and nicergoline represent exciting future options.KEY MESSAGESNeurotrophic keratopathy is a rare degenerative disease defined by decreased innervation to the cornea that is associated with significant morbidity.Treatment options range from lubrication alone to various medical and surgical treatments.Matrix regenerating therapy, plasma rich in growth factors, Thymosin ß4, Substance P/Insulin like growth factor-1, and nicergoline are exciting novel therapies that will influence how neurotrophic keratopathy is treated in the future.


Assuntos
Distrofias Hereditárias da Córnea , Ceratite , Transferência de Nervo , Doenças do Nervo Trigêmeo , Córnea/cirurgia , Distrofias Hereditárias da Córnea/cirurgia , Humanos , Ceratite/cirurgia , Doenças do Nervo Trigêmeo/cirurgia
3.
Entropy (Basel) ; 23(1)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467064

RESUMO

Our account provides a local, realist and fully non-causal principle explanation for EPR correlations, contextuality, no-signalling, and the Tsirelson bound. Indeed, the account herein is fully consistent with the causal structure of Minkowski spacetime. We argue that retrocausal accounts of quantum mechanics are problematic precisely because they do not fully transcend the assumption that causal or constructive explanation must always be fundamental. Unlike retrocausal accounts, our principle explanation is a complete rejection of Reichenbach's Principle. Furthermore, we will argue that the basis for our principle account of quantum mechanics is the physical principle sought by quantum information theorists for their reconstructions of quantum mechanics. Finally, we explain why our account is both fully realist and psi-epistemic.

4.
Entropy (Basel) ; 24(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35052038

RESUMO

Quantum information theorists have created axiomatic reconstructions of quantum mechanics (QM) that are very successful at identifying precisely what distinguishes quantum probability theory from classical and more general probability theories in terms of information-theoretic principles. Herein, we show how one such principle, Information Invariance and Continuity, at the foundation of those axiomatic reconstructions, maps to "no preferred reference frame" (NPRF, aka "the relativity principle") as it pertains to the invariant measurement of Planck's constant h for Stern-Gerlach (SG) spin measurements. This is in exact analogy to the relativity principle as it pertains to the invariant measurement of the speed of light c at the foundation of special relativity (SR). Essentially, quantum information theorists have extended Einstein's use of NPRF from the boost invariance of measurements of c to include the SO(3) invariance of measurements of h between different reference frames of mutually complementary spin measurements via the principle of Information Invariance and Continuity. Consequently, the "mystery" of the Bell states is understood to result from conservation per Information Invariance and Continuity between different reference frames of mutually complementary qubit measurements, and this maps to conservation per NPRF in spacetime. If one falsely conflates the relativity principle with the classical theory of SR, then it may seem impossible that the relativity principle resides at the foundation of non-relativisitic QM. In fact, there is nothing inherently classical or quantum about NPRF. Thus, the axiomatic reconstructions of QM have succeeded in producing a principle account of QM that reveals as much about Nature as the postulates of SR.

5.
Sci Rep ; 10(1): 15771, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978499

RESUMO

In 1981, Mermin published a now famous paper titled, "Bringing home the atomic world: Quantum mysteries for anybody" that Feynman called, "One of the most beautiful papers in physics that I know." Therein, he presented the "Mermin device" that illustrates the conundrum of quantum entanglement per the Bell spin states for the "general reader." He then challenged the "physicist reader" to explain the way the device works "in terms meaningful to a general reader struggling with the dilemma raised by the device." Herein, we show how "conservation per no preferred reference frame (NPRF)" answers that challenge. In short, the explicit conservation that obtains for Alice and Bob's Stern-Gerlach spin measurement outcomes in the same reference frame holds only on average in different reference frames, not on a trial-by-trial basis. This conservation is SO(3) invariant in the relevant symmetry plane in real space per the SU(2) invariance of its corresponding Bell spin state in Hilbert space. Since NPRF is also responsible for the postulates of special relativity, and therefore its counterintuitive aspects of time dilation and length contraction, we see that the symmetry group relating non-relativistic quantum mechanics and special relativity via their "mysteries" is the restricted Lorentz group.

6.
Entropy (Basel) ; 21(7)2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33267406

RESUMO

To answer Wheeler's question "Why the quantum?" via quantum information theory according to Bub, one must explain both why the world is quantum rather than classical and why the world is quantum rather than superquantum, i.e., "Why the Tsirelson bound?" We show that the quantum correlations and quantum states corresponding to the Bell basis states, which uniquely produce the Tsirelson bound for the Clauser-Horne-Shimony-Holt (CHSH) quantity, can be derived from conservation per no preferred reference frame (NPRF). A reference frame in this context is defined by a measurement configuration, just as with the light postulate of special relativity. We therefore argue that the Tsirelson bound is ultimately based on NPRF just as the postulates of special relativity. This constraint-based/principle answer to Bub's question addresses Fuchs' desideratum that we "take the structure of quantum theory and change it from this very overt mathematical speak ... into something like [special relativity]." Thus, the answer to Bub's question per Fuchs' desideratum is, "the Tsirelson bound obtains due to conservation per NPRF".

7.
Case Rep Ophthalmol Med ; 2016: 9786810, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27891274

RESUMO

A 41-year-old man with a history of gout presented with an enlarging eyelid growth. Clinical examination revealed a mildly indurated nodule at the lateral canthus. Following resection, histopathological examination revealed needle-shaped, crystalline material surrounded by multinucleated giant cells, findings consistent with gouty tophus. This represents just the sixth case of gouty tophus of the eyelid reported in the literature.

8.
J Acoust Soc Am ; 134(3): EL276-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23968060

RESUMO

The thermophone, conceived in 1917 by Arnold and Crandall, was a unique thermoacoustic loudspeaker. The high heat capacity per unit area (HCPUA) of thin-film materials at that time limited the usefulness of thermophones. Recently, researchers of carbon nanotubes (CNTs) have developed techniques to create a super-aligned thin-film of multi-walled CNTs, possessing extremely low HCPUA. This paper will discuss CNT thin-film loudspeaker theory as well as some initial investigations into the feasibility of a high-powered audio CNT speaker. The advantages of such a loudspeaker include: Ultra-lightweight, compact, no moving parts, low cost, and independence from expensive rare-earth materials.


Assuntos
Acústica/instrumentação , Amplificadores Eletrônicos , Nanotubos de Carbono , Som , Transdutores , Desenho de Equipamento , Estudos de Viabilidade , Modelos Teóricos , Movimento (Física) , Pressão , Temperatura , Condutividade Térmica
9.
J Acoust Soc Am ; 129(4): 2237-44, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21476678

RESUMO

Voice command sound pressure levels (SPLs) were recorded at distances up to 1500 m. Received SPLs were related to the meteorological condition during sound propagation and compared with the outdoor sound propagation standard ISO 9613-2. Intelligibility of received signals was calculated using ANSI S3.5. Intelligibility results for the present voice command indicate that meteorological condition imposes little to no effect on intelligibility when the signal-to-noise ratio (SNR) is low (<-9 dB) or high (>0 dB). In these two cases the signal is firmly unintelligible or intelligible, respectively. However, at moderate SNRs, variations in received SPL can cause a fully intelligible voice command to become unintelligible, depending on the meteorological condition along the sound propagation path. These changes in voice command intelligibility often occur on time scales as short as minutes during upward refracting conditions, typically found above ground during the day or upwind of a sound source. Reliably predicting the intelligibility of a voice command in a moderate SNR environment can be challenging due to the inherent variability imposed by sound propagation through the atmosphere.


Assuntos
Acústica , Meios de Comunicação , Emergências , Modelos Teóricos , Inteligibilidade da Fala , Aeroportos , Atmosfera , Planejamento em Desastres , Humanos , Ciência Militar , Acústica da Fala , Voz , Tempo (Meteorologia)
10.
Chest ; 140(1): 48-53, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21349931

RESUMO

BACKGROUND: Catheter-related thrombosis is a common complication in all anatomic sites, especially when smaller veins of the upper extremity are considered. It is presumed that the presence of a catheter within the lumen of a vein will decrease flow and potentially create stasis, and clinical data suggest that the size of the catheter impacts thrombosis rates. We sought to determine, both mathematically and experimentally, the impact of catheters on fluid flow rates. METHODS: We used fluid mechanics to calculate relative flow rates as a function of the ratio of the catheter to vein diameters. We also measured the flow rate of a blood analyte solution in an annular flow model using diameters that simulate the size of upper extremity veins and commonly used peripherally inserted central catheters (PICCs). RESULTS: We compared each of the derived relative flow rates to the experimentally determined ones for three cylinder sizes and found a correlation of r(2) = 0.90. We also confirmed that the decrease in fluid flow rate with each successive catheter size is statistically significant (P < .0001). CONCLUSIONS: Our results demonstrate that fluid flow is dramatically decreased by the insertion of a centrally located obstruction. Assuming that blood flow in veins behaves in a similar manner to our models, PICCs, in particular, may substantially decrease venous flow rates by as much as 93%.


Assuntos
Braço/irrigação sanguínea , Velocidade do Fluxo Sanguíneo/fisiologia , Cateterismo Venoso Central/instrumentação , Cateterismo Periférico/instrumentação , Catéteres/normas , Modelos Biológicos , Veias/fisiologia , Humanos , Veias/anatomia & histologia
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