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1.
Int J Med Sci ; 21(2): 265-276, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169586

RESUMO

Melanoma is a highly malignant tumor in the body. Long non-coding RNAs (lncRNAs) have been reported to be involved in the development of various tumors. Emerging evidence demonstrates the critical role of lncRNAs in melanoma development. In this study, we aimed to investigate the expression, biological function and regulatory mechanism of LINC00662 in melanomas. First, we found that LINC00662 was up-regulated in melanoma tissues and cell lines. High expression of LINC00662 in melanomas was associated with a poor patient prognosis. Silencing of LINC00662 suppressed the proliferation, migration, and invasion of melanoma cells in vitro and in vivo, while overexpression of LINC00662 promoted melanoma cell proliferation in vitro. Bioinformatics analysis, dual-luciferase assay, and RIP assay confirmed that LINC00662 competitively regulated miR-107. Silencing of LINC00662 upregulated miR-107 expression in a melanoma cell line. Inhibition of miR-107 significantly reversed the inhibitory effect of LINC00662 silencing on cell proliferation and migration. Furthermore, POU3F2 was validated as a downstream target of LINC00662/miR107 and was downregulated when LINC00662 was silenced. Overexpressing POU3F2 attenuated the effect of si-LINC00662 on cellular functions. In addition, the results also showed that the ß-catenin pathway was involved in a si-LINC00662-induced function in melanoma. Overall, our results confirmed that LINC00662 promoted melanoma progression by sponging miR107 and inducing POU3F2, highlighting the mechanism of the LINC00662/miR-107/POU3F2 axis in melanoma cell proliferation and invasion.


Assuntos
Melanoma , MicroRNAs , RNA Longo não Codificante , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Melanoma/genética , beta Catenina/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais/genética , Proliferação de Células/genética , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica
2.
Int J Mol Sci ; 23(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35562990

RESUMO

Sleep and wakefulness are basic behavioral states that require coordination between several brain regions, and they involve multiple neurochemical systems, including neuropeptides. Neuropeptides are a group of peptides produced by neurons and neuroendocrine cells of the central nervous system. Like traditional neurotransmitters, neuropeptides can bind to specific surface receptors and subsequently regulate neuronal activities. For example, orexin is a crucial component for the maintenance of wakefulness and the suppression of rapid eye movement (REM) sleep. In addition to orexin, melanin-concentrating hormone, and galanin may promote REM sleep. These results suggest that neuropeptides play an important role in sleep-wake regulation. These neuropeptides can be divided into three categories according to their effects on sleep-wake behaviors in rodents and humans. (i) Galanin, melanin-concentrating hormone, and vasoactive intestinal polypeptide are sleep-promoting peptides. It is also noticeable that vasoactive intestinal polypeptide particularly increases REM sleep. (ii) Orexin and neuropeptide S have been shown to induce wakefulness. (iii) Neuropeptide Y and substance P may have a bidirectional function as they can produce both arousal and sleep-inducing effects. This review will introduce the distribution of various neuropeptides in the brain and summarize the roles of different neuropeptides in sleep-wake regulation. We aim to lay the foundation for future studies to uncover the mechanisms that underlie the initiation, maintenance, and end of sleep-wake states.


Assuntos
Galanina , Neuropeptídeos , Galanina/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Neuropeptídeos/metabolismo , Orexinas/farmacologia , Sono/fisiologia , Peptídeo Intestinal Vasoativo/farmacologia
3.
Nanotechnology ; 32(1): 012002, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679577

RESUMO

Recent progress in artificial intelligence is largely attributed to the rapid development of machine learning, especially in the algorithm and neural network models. However, it is the performance of the hardware, in particular the energy efficiency of a computing system that sets the fundamental limit of the capability of machine learning. Data-centric computing requires a revolution in hardware systems, since traditional digital computers based on transistors and the von Neumann architecture were not purposely designed for neuromorphic computing. A hardware platform based on emerging devices and new architecture is the hope for future computing with dramatically improved throughput and energy efficiency. Building such a system, nevertheless, faces a number of challenges, ranging from materials selection, device optimization, circuit fabrication and system integration, to name a few. The aim of this Roadmap is to present a snapshot of emerging hardware technologies that are potentially beneficial for machine learning, providing the Nanotechnology readers with a perspective of challenges and opportunities in this burgeoning field.

4.
Health Econ ; 30(9): 2200-2216, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34128281

RESUMO

In clinical trials, smoking-cessation aids (SCAs) have proven to be effective at improving the odds of smoking cessation. Because of the effectiveness of SCAs in these settings, many countries have adopted the coverage of SCAs to reduce tobacco use. However, the effect of such coverage on tobacco use is ambiguous. On one hand, the coverage may have the intended effect and reduce tobacco use. On the other hand, the coverage may cause beneficiaries to participate in tobacco use more as the drug coverage protects beneficiaries from future costs associated with tobacco use. To understand the effect of SCA coverage, we examine it using 2008-2012 Canadian Tobacco Use Monitoring Survey and a difference-in-differences approach. We find that SCA coverage increases cigarette and cigarillo use. Moreover, the effect of SCA coverage on tobacco use is stronger in men and in those with at least a college education. Our results point to the unintended consequences of the coverage of SCAs on tobacco use.


Assuntos
Abandono do Hábito de Fumar , Tabagismo , Canadá , Humanos , Masculino , Fumar , Prevenção do Hábito de Fumar , Uso de Tabaco
5.
Health Econ ; 30(3): 505-524, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33315287

RESUMO

Countries seeking to move away from a purely fee-for-service (FFS) system may consider a hybrid approach whereby only some procedures are paid by FFS while others are paid prospectively. Yet little evidence exists whether such a hybrid payment system contains overall costs without adverse influences on health outcomes. In 2003, Japan experienced a reform from FFS to a hybrid payment system in which only some inpatient procedures were paid prospectively. We exploit this reform to test how such a hybrid system affects overall costs and health outcomes. Briefly, we find that healthcare providers responded opportunistically to the reform, moving some procedures out of the bundled inpatient setting to FFS services, leading to no reduction in cost. There was some evidence of a moderate deterioration in health outcomes, in terms of a decline in the probability of symptoms being cured at discharge. In sum, our results suggest that in some cases, a hybrid payment system can be non-superior to either FFS or prospective payment system.


Assuntos
Sistema de Pagamento Prospectivo , Mecanismo de Reembolso , Planos de Pagamento por Serviço Prestado , Pessoal de Saúde , Humanos , Salários e Benefícios
6.
Proc Natl Acad Sci U S A ; 114(26): 6717-6721, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28611222

RESUMO

A fundamental building block for nanophotonics is the ability to achieve negative refraction of polaritons, because this could enable the demonstration of many unique nanoscale applications such as deep-subwavelength imaging, superlens, and novel guiding. However, to achieve negative refraction of highly squeezed polaritons, such as plasmon polaritons in graphene and phonon polaritons in boron nitride (BN) with their wavelengths squeezed by a factor over 100, requires the ability to flip the sign of their group velocity at will, which is challenging. Here we reveal that the strong coupling between plasmon and phonon polaritons in graphene-BN heterostructures can be used to flip the sign of the group velocity of the resulting hybrid (plasmon-phonon-polariton) modes. We predict all-angle negative refraction between plasmon and phonon polaritons and, even more surprisingly, between hybrid graphene plasmons and between hybrid phonon polaritons. Graphene-BN heterostructures thus provide a versatile platform for the design of nanometasurfaces and nanoimaging elements.

7.
Neural Comput ; 31(4): 765-783, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30764742

RESUMO

We present a novel recurrent neural network (RNN)-based model that combines the remembering ability of unitary evolution RNNs with the ability of gated RNNs to effectively forget redundant or irrelevant information in its memory. We achieve this by extending restricted orthogonal evolution RNNs with a gating mechanism similar to gated recurrent unit RNNs with a reset gate and an update gate. Our model is able to outperform long short-term memory, gated recurrent units, and vanilla unitary or orthogonal RNNs on several long-term-dependency benchmark tasks. We empirically show that both orthogonal and unitary RNNs lack the ability to forget. This ability plays an important role in RNNs. We provide competitive results along with an analysis of our model on many natural sequential tasks, including question answering, speech spectrum prediction, character-level language modeling, and synthetic tasks that involve long-term dependencies such as algorithmic, denoising, and copying tasks.


Assuntos
Redes Neurais de Computação , Simulação por Computador , Humanos , Idioma , Aprendizagem , Lógica , Memória
8.
Aesthetic Plast Surg ; 41(4): 788-792, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28374295

RESUMO

BACKGROUND: Nipple hypertrophy is a common aesthetic issue for Asian women. Thus, methods to correct this problem are needed. Several nipple reduction procedures have been reported, but all have shortcomings. In this article, we propose a new method to reduce both the height and diameter of the nipple without affecting its function. METHODS: Sixteen female patients, between the ages of 24-41 years, underwent a new nipple reduction method in our department between May 17, 2010, and May 5, 2014. Three crescent-shaped lines were drawn from the top of the side wall of the nipple, extending to the areola. This design reduces both the diameter and height of the nipple with minimal tissue manipulation. RESULTS: Before surgery, the mean diameter and height of the nipple were 15.9 ± 2.7 and 18.3 ± 3.1 mm, respectively, with the patient in the supine position. Immediately after surgery, the mean diameter and height of the nipple were 9.1 ± 1.7 and 7.9 ± 2.1 mm, respectively. No major complications, such as nipple necrosis, infection, delayed wound healing, or loss of sensation, were noted. CONCLUSIONS: This new surgical technique allows the creation of a new nipple of the desired height and diameter with excellent aesthetic results and without significant complications. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Mamilos/patologia , Mamilos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/transplante , Adulto , Estética , Feminino , Seguimentos , Humanos , Hipertrofia/patologia , Hipertrofia/cirurgia , Mamoplastia/métodos , Medição de Risco , Retalhos Cirúrgicos/irrigação sanguínea , Taiwan , Resultado do Tratamento , Adulto Jovem
9.
Aesthetic Plast Surg ; 41(1): 73-80, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28008460

RESUMO

BACKGROUND: Fat-preserving lower blepharoplasty techniques and filling techniques using autologous or non-autologous materials are increasingly used to treat tear trough deformity. However, there has been no definitive comparison of the results of fat repositioning versus autologous fat grafting for this condition. The authors used statistical analysis to compare the results of the two methods. METHODS: From October 2013 to September 2015, a total of 101 patients, aged 20-43 years, underwent fat repositioning or autologous fat grafting in our department. Group 1 (51 patients, 102 eyes) underwent intraorbital fat repositioning with septal reset by transconjunctival lower blepharoplasty. Group 2 (50 patients, 100 eyes) underwent autologous fat grafting by lipoinjection. RESULTS: No significant complications occurred in any patient postoperatively. Four of 102 eyes in Group 1 and seven of 100 eyes in Group 2 had no improvement; the rest had different degrees of improvement. In Grade II and III deformities, fat repositioning resulted in significantly greater improvement of grade compared with autologous fat grafting. The surgical method of Group 1 resulted in better curative effects than that of Group 2. CONCLUSION: In patients with tear trough deformity and without obvious skin or orbicularis oculi muscle laxity, both fat repositioning and autologous fat grafting are acceptable for mild deformity. In patients with higher-grade deformities, fat repositioning produced superior results than autologous fat grafting. LEVEL OF EVIDENCE IV: This journal requires that the authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266 .


Assuntos
Tecido Adiposo/transplante , Blefaroplastia/métodos , Pálpebras/anormalidades , Pálpebras/cirurgia , Adulto , Povo Asiático/estatística & dados numéricos , Estudos de Coortes , Estética , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Medição de Risco , Técnicas de Sutura , Taiwan , Transplante Autólogo/métodos , Resultado do Tratamento , Adulto Jovem
10.
Aesthetic Plast Surg ; 39(6): 942-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26487658

RESUMO

BACKGROUND: Polyacrylamide hydrogel (PAAG) can cause serious complications during facial augmentation. Previous studies have reported complications following PAAG injections to correct tear troughs. METHODS: We report a rare case of tear trough deformity following PAAG injections. We developed a comprehensive treatment plan including transcutaneous blepharoplasty and fat grafting to address the presenting complications. RESULTS: The patient showed flat lower lids and no more complications 1 year after surgery. CONCLUSIONS: Blepharoplasty combined with fat grafting is an effective approach to eliminate PAAG injection complications in tear troughs. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Resinas Acrílicas/efeitos adversos , Tecido Adiposo/transplante , Blefaroplastia/métodos , Preenchedores Dérmicos/efeitos adversos , Doenças Palpebrais/induzido quimicamente , Doenças Palpebrais/cirurgia , Resinas Acrílicas/administração & dosagem , Adulto , Feminino , Humanos , Injeções
11.
Opt Express ; 22 Suppl 7: A1895-906, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25607503

RESUMO

A high performance solar absorber using a 2D tantalum superlattice photonic crystal (PhC) is proposed and its design is optimized for high-temperature energy conversion. In contrast to the simple lattice PhC, which is limited by diffraction in the short wavelength range, the superlattice PhC achieves solar absorption over broadband spectral range due to the contribution from two superposed lattices with different cavity radii. The superlattice PhC geometry is tailored to achieve maximum thermal transfer efficiency for a low concentration system of 250 suns at 1500 K reaching 85.0% solar absorptivity. In the high concentration case of 1000 suns, the superlattice PhC absorber achieves a solar absorptivity of 96.2% and a thermal transfer efficiency of 82.9% at 1500 K, amounting to an improvement of 10% and 5%, respectively, versus the simple square lattice PhC absorber. In addition, the performance of the superlattice PhC absorber is studied in a solar thermophotovoltaic system which is optimized to minimize absorber re-emission by reducing the absorber-to-emitter area ratio and using a highly reflective silver aperture.

12.
Opt Express ; 22(18): 21711-8, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25321547

RESUMO

We report the design of dielectric-filled anti-reflection coated (ARC) two-dimensional (2D) metallic photonic crystals (MPhCs) capable of omnidirectional, polarization insensitive, wavelength selective emission/absorption. Using non-linear global optimization methods, optimized hafnium oxide (HfO2)-filled ARC 2D Tantalum (Ta) PhC designs exhibiting up to 26% improvement in emittance/absorptance at wavelengths λ below a cutoff wavelength λc over the unfilled 2D TaPhCs are demonstrated. The optimized designs possess high hemispherically average emittance/absorptance εH of 0.86 at λ < λc and low εH of 0.12 at λ > λc.

13.
SSM Popul Health ; 22: 101414, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37168248

RESUMO

This study investigates the relationship between mental health and employment using an instrumental variable approach with the 2012 Canadian Community Health Survey-Mental Health. Using a family member's mental health problem(s) as an instrument for poor mental health, the estimates reveal that poor mental health significantly reduces employment outcomes. These findings are robust to various specifications, such as an alternative instrument and a relaxation of the exclusion restriction assumption. In addition, the relationship is driven mainly by men and younger workers. Moreover, the findings suggest that the relationship is mediated by a decline in cognitive abilities, such as difficulties in concentration and motivation, and social relations with acquaintances and friends. Finally, the estimates show that this phenomenon is contagious: poor mental health has a significant spillover effect on coworkers' mental health in workplaces. This study demonstrates the importance of mental health illness in Canada and other developed countries.

14.
Sci Rep ; 13(1): 6828, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37100857

RESUMO

Dietary restriction (DR) has been a very important discovery in modern aging biology research. Its remarkable anti-aging effect has been proved in a variety of organisms, including members of Lepidoptera, but mechanisms by which DR increases longevity are not fully understood. By using the silkworm (Bombyx mori), a model of lepidopteran insect, we established a DR model, isolated hemolymph from fifth instar larvae and employed LC-MS/MS metabolomics to analyze the effect of DR on the endogenous metabolites of silkworm, and tried to clarify the mechanism of DR to prolong lifespan. We identified the potential biomarkers by analyzing the metabolites of the DR and control groups. Then, we constructed relevant metabolic pathways and networks with MetaboAnalyst. DR significantly prolonged the lifespan of silkworm. The differential metabolites between the DR and control groups were mainly organic acids (including amino acid), and amines. These metabolites are involved in metabolic pathways such as amino acid metabolism. Further analysis showed that, the levels of 17 amino acids were significantly changed in the DR group, indicating that the prolonged lifespan was mainly due to changes in amino acid metabolism. Furthermore, we identified 41 and 28 unique differential metabolites in males and females, respectively, demonstrating sex differences in biological responses to DR. The DR group showed higher antioxidant capacity and lower lipid peroxidation and inflammatory precursors, with differences between the sexes. These results provide evidence for various DR anti-aging mechanisms at the metabolic level and novel reference for the future development of DR-simulating drugs or foods.


Assuntos
Bombyx , Animais , Feminino , Masculino , Bombyx/metabolismo , Larva , Longevidade , Aminoácidos/metabolismo , Hemolinfa/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem
15.
Nat Commun ; 14(1): 3000, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225707

RESUMO

Convolutional neural networks are an important category of deep learning, currently facing the limitations of electrical frequency and memory access time in massive data processing. Optical computing has been demonstrated to enable significant improvements in terms of processing speeds and energy efficiency. However, most present optical computing schemes are hardly scalable since the number of optical elements typically increases quadratically with the computational matrix size. Here, a compact on-chip optical convolutional processing unit is fabricated on a low-loss silicon nitride platform to demonstrate its capability for large-scale integration. Three 2 × 2 correlated real-valued kernels are made of two multimode interference cells and four phase shifters to perform parallel convolution operations. Although the convolution kernels are interrelated, ten-class classification of handwritten digits from the MNIST database is experimentally demonstrated. The linear scalability of the proposed design with respect to computational size translates into a solid potential for large-scale integration.

16.
Water Environ Res ; 84(7): 562-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22876478

RESUMO

Adsorption of microcystin-LR (MC-LR) from water using iron oxide (alpha-Fe2O3) nanoparticles was investigated in this study. Adsorption of MC-LR adsorption was well-described by a pseudo second order kinetics model and Freundlich and Langmuir isotherm equations at 15 to 35 degrees C. Thermodynamic analysis showed that the Gibbs free energy was negative, whereas standard enthalpy and entropy changes were positive at this temperature range. These findings suggest that the adsorption of MC-LR on iron oxide nanoparticles was spontaneous and endothermic. The effects of initial pH, inorganic cations, and competing compounds with carboxyl groups on absorption of MC-LR were also evaluated. Typically, adsorption efficiency decreased with increasing pH from 2 to 11. Sodium ions did not appear to significantly affect MC-LR adsorption, whereas calcium ions slightly enhanced the MC-LR adsorption capacity of the iron oxide nanoparticles. Moreover, the inhibiting effect of competing organic compounds was increased with increasing numbers of carboxyl groups, as follows: citric acid (3)>oxalic acid (2)>benzoic acid (1).


Assuntos
Compostos Férricos/química , Nanopartículas Metálicas/química , Microcistinas/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Toxinas Marinhas , Fatores de Tempo
17.
Front Mol Biosci ; 9: 800122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35174214

RESUMO

Circular RNAs (circRNAs) play a crucial role in the pathogenesis of various fibrotic diseases, but the potential biological function and expression profile of circRNAs in keloids remain unknown. Herein, microarray technology was applied to detect circRNA expression in four patient-derived keloid dermal fibroblasts (KDFs) and normal dermal fibroblasts (NDFs). A total of 327 differentially expressed (DE) circRNAs (fold change > 1.5, p < 0.05) were identified with 195 upregulated and 132 downregulated circRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the upregulated circRNAs were mainly enriched in the cytoskeleton and tight junctions, while the downregulated circRNAs were related to morphogenesis of the epithelium and axonal guidance. To explore the function of DE circRNAs, a circRNA-miRNA-mRNA network, including five circRNAs, nine miRNAs, and 235 correlated mRNAs, was constructed using bioinformatics analyses. The expression of five DE circRNAs was validated by qRT-PCR in 18 pairs of KDFs and NDFs, and hsa_circ_0006867 showed promising regulatory function in keloids in vitro. Silencing hsa_circ_00006867 suppressed the proliferation, migration, and invasion of keloid fibroblasts. RNA-binding protein immunoprecipitation (RIP) assays indicated that hsa_circ_00006867 may serve as a platform for miRNA binding to Argonaute (AGO) 2. In addition, hsa-miR-29a-5p may be a potential target miRNA of hsa_circ_00006867. Taken together, our research provided multiple novel clues to understand the pathophysiologic mechanism of keloids and identified hsa_circ_0006867 as a biomarker of keloids.

18.
Nat Commun ; 13(1): 2694, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577783

RESUMO

Breakthroughs in the field of object recognition facilitate ubiquitous applications in the modern world, ranging from security and surveillance equipment to accessibility devices for the visually impaired. Recently-emerged optical computing provides a fundamentally new computing modality to accelerate its solution with photons; however, it still necessitates digital processing for in situ application, inextricably tied to Moore's law. Here, from an entirely optical perspective, we introduce the concept of neuro-metamaterials that can be applied to realize a dynamic object- recognition system. The neuro-metamaterials are fabricated from inhomogeneous metamaterials or transmission metasurfaces, and optimized using, such as topology optimization and deep learning. We demonstrate the concept in experiments where living rabbits play freely in front of the neuro-metamaterials, which enable to perceive in light speed the rabbits' representative postures. Furthermore, we show how this capability enables a new physical mechanism for creating dynamic optical mirages, through which a sequence of rabbit movements is converted into a holographic video of a different animal. Our work provides deep insight into how metamaterials could facilitate a myriad of in situ applications, such as illusive cloaking and speed-of-light information display, processing, and encryption, possibly ushering in an "Optical Internet of Things" era.


Assuntos
Materiais de Construção , Reconhecimento Psicológico , Animais , Coelhos , Visão Ocular
19.
Light Sci Appl ; 11(1): 30, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115497

RESUMO

Matrix computation, as a fundamental building block of information processing in science and technology, contributes most of the computational overheads in modern signal processing and artificial intelligence algorithms. Photonic accelerators are designed to accelerate specific categories of computing in the optical domain, especially matrix multiplication, to address the growing demand for computing resources and capacity. Photonic matrix multiplication has much potential to expand the domain of telecommunication, and artificial intelligence benefiting from its superior performance. Recent research in photonic matrix multiplication has flourished and may provide opportunities to develop applications that are unachievable at present by conventional electronic processors. In this review, we first introduce the methods of photonic matrix multiplication, mainly including the plane light conversion method, Mach-Zehnder interferometer method and wavelength division multiplexing method. We also summarize the developmental milestones of photonic matrix multiplication and the related applications. Then, we review their detailed advances in applications to optical signal processing and artificial neural networks in recent years. Finally, we comment on the challenges and perspectives of photonic matrix multiplication and photonic acceleration.

20.
Soc Sci Med ; 272: 113714, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33545495

RESUMO

This study investigates the impacts of anticancer drug parity laws on mortality rates in the United States using a difference-in-differences approach. Using data from 2004 to 2017 Compressed Mortality Files, we show that the anticancer drug parity laws reduce the mortality rate for head/neck malignant cancers but have no impact on malignant cancers of other types. We also rule out an insurance expansion channel that may influence the relationship between anticancer drug parity laws and malignant cancer mortality. Our results are robust to various specifications and falsification tests. Our findings imply that providing equal access to oral anticancer drugs is an effective tool for the prevention of premature mortality.


Assuntos
Antineoplásicos , Antineoplásicos/uso terapêutico , Humanos , Estados Unidos/epidemiologia
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