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1.
N Y Univ Law Rev ; 98(6): 1831-1880, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38187890

RESUMO

This Article examines how the rapid deregulation and rampant possession of firearms is likely going to impact policing, and the constitutional law that governs it. For the longest time, lawful gun carry, concealed or open, was exceedingly rare. For a police officer to see a gun was both to see danger, and a crime in progress. This link among guns, danger, and unlawful possession has shaped much of the law of policing. But now, this understanding of the world is in its last stages of unraveling. In nearly all states, guns are no longer unlawful to own and carry by default. In many, they are barely regulated. Recent Supreme Court Second Amendment decisions like New York State Rifle & Pistol Association v. Bruen serve only to hasten where state laws already were headed. For police, however, the harm guns can do exists irrespective of what the law has to say about the legality of carrying them. As a result, the nation's gun laws are on a collision course with the practice and law of policing. This Article explores how the constitutional law governing policing is changing and will change in the face of gun legalization. Part I of this Article explains the ubiquitous role guns play in the life of a police officer, and what actions guns lead police to take. Part II is about the legal doctrine of policing, both before and after firearm legalization. It details how the law shaped what police could do in order to protect themselves and others, and how that law is changing to accommodate legalization. Police now must operate in a terrain that increasingly is uncertain as to their lawful authority, and that in many instances may put them or others in jeopardy. Part III examines how the shifting laws of guns and policing might impact police behavior, likely resulting in ad hoc carve-outs for police authority that-if history is any guide-overwhelmingly will be imposed on Black and Brown communities.

2.
Eur Phys J E Soft Matter ; 45(10): 84, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269469

RESUMO

We determine the equilibrium chain end probability density [Formula: see text] for a one-dimensional ideal chain of N monomers grafted to a planar surface. This distribution is also the distribution function of a three-dimensional chain where the tangential dimensions y, z are integrated out of the distribution. With a small modification of the analysis of Erukhimovich, Johner, and Joanny for free chains near a wall, we are able to obtain exact results for [Formula: see text] for any monomer number N though with the restriction that the monomer-monomer bonds lengths are exponentially distributed. In particular, we obtain exact values for [Formula: see text] and its derivative [Formula: see text] at the surface for any N and the full profile [Formula: see text] for selected values of N. To determine the effect of the bond distribution, we find [Formula: see text] numerically for Gaussian and uniformly distributed one-dimensional bonds and compare with the exact results for exponential bonds. We suggest several ways to quantify the effect of bond type based both on [Formula: see text] near the surface and in the scaling region [Formula: see text]. We then extract the large N limit of [Formula: see text] and show that it is similar to the chain end probability for continuous chains but shifted toward smaller x. We show the amount of shift is a measure of the magnitude of the correction to the continuous chain [Formula: see text]. We derive the value of the shift for exponential bonds and show that the value is different for other bond types. We argue the shift can be interpreted as an effective surface behind the actual surface.

3.
Sensors (Basel) ; 19(24)2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31847275

RESUMO

We developed a microwave glucose sensor based on the modified first-order Hilbert curve design and measured glucose concentration in aqueous solutions by using a real-time microwave near-field electromagnetic interaction technique. We observed S21 transmission parameters of the sensor at resonant frequencies depend on the glucose concentration. We could determine the glucose concentration in the 0-250 mg/dL concentration range at an operating frequency of near 6 GHz. The measured minimum detectable signal was 0.0156 dB/(mg/dL) and the measured minimum detectable concentration was 1.92 mg/dL. The simulation result for the minimum detectable signal and the minimum detectable concentration was 0.0182 dB/(mg/dL) and 1.65 mg/dL, respectively. The temperature instability of the sensor for human glycemia in situ measurement range (27-34 °C for fingers and 36-40 °C for body temperature ranges) can be improved by the integration of the temperature sensor in the microwave stripline platform and the obtained data can be corrected during signal processing. The microwave signal-temperature dependence is almost linear with the same slope for a glucose concentration range of 50-150 mg/dL. The temperature correlation coefficient is 0.05 dB/°C and 0.15 dB/°C in 27-34 °C and 36-40 °C temperature range, respectively. The presented system has a cheap, easy fabrication process and has great potential for non-invasive glucose monitoring.

5.
Heliyon ; 10(2): e24477, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293417

RESUMO

The resonant interaction of a dielectric-coated conductive rod with the X-band microwave field is investigated. The magnetic field distribution of the Goubau standing radial surface waves was experimentally visualized by using a thermo-elastic optical indicator microscope, and the corresponding electric field distribution was determined via numerical simulations. These field distributions are characterized by a certain pattern of antinodes distinctive for standing waves. An analysis of these field distributions allows one to couple a coated rod with a cut Goubau line. A rod placed in the gap region perpendicular to the Goubau line results in a sharp rejection band in the transmission spectrum which is extremely sensitive to the changes in the surrounding media. The shifting rate of the resonance as a function of the dielectric shell thickness is approximately 1.4 GHz/mm. The Q-factor of copper rods depends on their size and dielectric shell thickness. Longer rods with more energy localization areas have higher Q-factors, typically 1.7 times higher (12.7 vs. 7.5). Moreover, incorporating a dielectric shell enhances energy confinement and can elevate the Q-factor by as much as 22 %. When a 25 mm Cu rod is situated inside a cut Goubau line system, the Q-factor values are significantly higher, with a ratio of 275 to 13. With the addition of a dielectric shell, the Q-factor can be elevated by 58 %. The versatility of the proposed controllable system makes it possible to tune the operating spectrum towards higher GHz and THz frequencies.

6.
JAMA Surg ; 159(8): 939-947, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38809546

RESUMO

Importance: A new liver allocation policy was implemented by United Network for Organ Sharing (UNOS) in February 2020 with the stated intent of improving access to liver transplant (LT). There are growing concerns nationally regarding the implications this new system may have on LT costs, as well as access to a chance for LT, which have not been captured at a multicenter level. Objective: To characterize LT volume and cost changes across the US and within specific center groups and demographics after the policy implementation. Design, Setting, and Participants: This cross-sectional study collected and reviewed LT volume from multiple centers across the US and cost data with attention to 8 specific center demographics. Two separate 12-month eras were compared, before and after the new UNOS allocation policy: March 4, 2019, to March 4, 2020, and March 5, 2020, to March 5, 2021. Data analysis was performed from May to December 2022. Main Outcomes and Measures: Center volume, changes in cost. Results: A total of 22 of 68 centers responded comparing 1948 LTs before the policy change and 1837 LTs postpolicy, resulting in a 6% volume decrease. Transplants using local donations after brain death decreased 54% (P < .001) while imported donations after brain death increased 133% (P = .003). Imported fly-outs and dry runs increased 163% (median, 19; range, 1-75, vs 50, range, 2-91; P = .009) and 33% (median, 3; range, 0-16, vs 7, range, 0-24; P = .02). Overall hospital costs increased 10.9% to a total of $46 360 176 (P = .94) for participating centers. There was a 77% fly-out cost increase postpolicy ($10 600 234; P = .03). On subanalysis, centers with decreased LT volume postpolicy observed higher overall hospital costs ($41 720 365; P = .048), and specifically, a 122% cost increase for liver imports ($6 508 480; P = .002). Transplant centers from low-income states showed a significant increase in hospital (12%) and import (94%) costs. Centers serving populations with larger proportions of racial and ethnic minority candidates and specifically Black candidates significantly increased costs by more than 90% for imported livers, fly-outs, and dry runs despite lower LT volume. Similarly, costs increased significantly (>100%) for fly-outs and dry runs in centers from worse-performing health systems. Conclusions and Relevance: Based on this large multicenter effort and contrary to current assumptions, the new liver distribution system appears to place a disproportionate burden on populations of the current LT community who already experience disparities in health care. The continuous allocation policies being promoted by UNOS could make the situation even worse.


Assuntos
Transplante de Fígado , Obtenção de Tecidos e Órgãos , Transplante de Fígado/economia , Humanos , Estudos Transversais , Estados Unidos , Obtenção de Tecidos e Órgãos/economia , Obtenção de Tecidos e Órgãos/legislação & jurisprudência , Política de Saúde , Masculino , Feminino , Listas de Espera
7.
Sci Rep ; 13(1): 18457, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891377

RESUMO

A new practical imaging technique was presented for metamaterial characterization and investigation by visualizations of the magnetic microwave near-field (H-MWNF) distributions on a metamaterial's surface using the method of thermo-elastic optical indicator microscopy (TEOIM). ITO-based transparent and ceramic-based opaque metamaterial structures were designed for magnetic near-field visualization. Depending on the incident microwave field polarization, the TEOIM system allows the characterization of the metamaterial properties and microwave interaction behavior. The working principle of the periodic structures was investigated through numerical simulations, and the obtained results exhibited strong agreement when compared with experimental observations. Moreover, the visualization of the H-MWNF revealed the potential to characterize and evaluate the absorption and transmission properties effectively.

8.
J Bus Ethics ; : 1-27, 2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36818159

RESUMO

Professional attire has traditionally been regarded as a sign of ethicality. However, recent trends towards a more casual workplace may have altered the general public's attire-based perceptions. To determine whether these trends have rendered the association between professional attire and ethicality obsolete, we draw on signaling theory and we examine, in two laboratory studies with working samples, the main effects of attire style (i.e., business formal, business casual, casual) on perceptions of employee ethicality. We also assess the mediating effects of attire appropriateness, the moderating effects of context (industry type), as well as their combined moderated-mediation effects in the relation between attire style and the outcome of interest. We find that casual attire is perceived as less ethical than business casual attire in both studies but is perceived as less ethical than business formal attire in the first study only. Moreover, the effect of attire style on perceptions of ethicality is mediated by perceptions of attire appropriateness. Lastly, we found inconclusive results for the moderated-mediation model, which suggest a more intricate effect of industry type than originally proposed. Three subsequent focus groups with working professionals provided additional insights into our findings and revealed workplace-relevant outcomes associated with perceptions of ethicality. Theoretical and practical implications, study limitations, and future research avenues are discussed.

9.
Sci Rep ; 12(1): 6150, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414676

RESUMO

Visualizations of the microwave electric and magnetic near-field distributions of radio-frequency (RF) filters were performed using the technique of thermoelastic optical indicator microscopy (TEOIM). New optical indicators based on periodic dielectric-metal structures were designed for electric field visualization. Depending on the structure orientation, such metasurface-based indicators allow separately visualization of the Ex and Ey components of the in-plane electric field. Numerical simulations were conducted to examine the working principle of the designed indicator structures, and the results were compared to the experimental, showing good agreement. In addition, the 3D visualization of the microwave near-field distribution was built, to show the field intensity and distribution dependencies on the distance from the RF filter.

10.
J Nanosci Nanotechnol ; 11(5): 4222-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21780431

RESUMO

A near-field scanning microwave microscope (NSMM) is used to detect sequence-specific hybridization between surface-immobilized and free DNA single strands. Hybridization between target (free) and capture (immobilized) sequences leads to changes in the reflection coefficient (S11) which are measured by the NSMM. These changes are caused by hybridization-induced modification of the dielectric constant profile of the DNA film. NSMM instrumentation does not require labeling of target sequences with fluorophores or other tagging groups. The physical basis of reflection coefficient changes underpinning the NSMM approach is discussed.


Assuntos
DNA/genética , Microscopia/instrumentação , Micro-Ondas , Hibridização de Ácido Nucleico , Sequência de Bases , Primers do DNA
11.
Sci Rep ; 11(1): 2589, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510224

RESUMO

In this study, a new optical method is presented to determine the concentrations of NaCl and glucose aqueous solutions by using a thermo-elastic optical indicator microscope. By measuring the microwave near-field distribution intensity, concentration changes of NaCl and glucose aqueous solutions were detected in the 0-100 mg/ml range, when exposed to microwave irradiation at 12 GHz frequency. Microwave near-field distribution intensity decreased as the NaCl or glucose concentration increased due to the changes of the absorption properties of aqueous solution. This method provides a novel approach for monitoring NaCl and glucose in biological liquids by using a CCD sensor capable of visualizing NaCl and glucose concentrations without scanning.

12.
Pediatr Transplant ; 13(4): 451-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18785906

RESUMO

RSV can cause respiratory illness after SOT, yet preventive recommendations are lacking for this population. To ascertain current preventive practices against RSV disease in pediatric SOT candidates and recipients, a survey was developed. The survey was mailed to 108 SOT programs in the United States (liver, 42; heart, 28; lung, 11; intestinal, 25; and heart-lung, 2). Results were tabulated and analyzed using standard methods. Sixty-two percent (67/108) of surveys were completed. Forty-nine percent (33/67) of programs reported using RSV prophylaxis; palivizumab was used at 97% (32/33) of centers with 26 giving palivizumab to candidates and 27 to recipients. Prophylaxis was provided to infants aged 0-12 months by 27/29 (93%) of responding centers; 23/29 of centers extended its use to infants aged 0-24 months. Three centers gave prophylaxis to children between ages two and four yr and two centers for those over four yr. RSV prophylactic strategies, and in particular the use of palivizumab, are employed by almost 50% of responding pediatric SOT centers. Strategies varied at centers based on age and organ type. Data on RSV hospitalization and outcome are needed to refine approaches to RSV immunoprophylaxis in these high-risk patients.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antivirais/uso terapêutico , Transplante de Órgãos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Anticorpos Monoclonais Humanizados , Pré-Escolar , Pesquisas sobre Atenção à Saúde , Humanos , Lactente , Recém-Nascido , Palivizumab
13.
Ultramicroscopy ; 108(10): 1058-61, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18547735

RESUMO

We observed tris-8-hydroxyquinoline aluminum (Alq3) thin films dependence on substrate heating temperatures by using a near-field microwave microprobe (NFMM) and by optical absorption at wavelengths between 200 and 900 nm. The changes of absorption intensity at different substrate heating temperatures are correlated to the changes in the sheet resistance of Alq3 thin films.

14.
Sci Rep ; 7: 43804, 2017 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-28252018

RESUMO

We report a simultaneous imaging method of the temperature and the magnetic field distributions based on the magneto optical indicator microscopy. The present method utilizes an optical indicator composed of a bismuth-substituted yttrium iron garnet thin film, and visualizes the magnetic field and temperature distributions through the magneto-optical effect and the temperature dependent optical absorption of the garnet thin film. By using a printed circuit board that carries an electric current as a device under test, we showed that the present method can visualize the magnetic field and temperature distribution simultaneously with a comparable temperature sensitivity (0.2 K) to that of existing conventional thermal imagers. The present technique provides a practical way to get a high resolution magnetic and thermal image at the same time, which is valuable in investigating how thermal variation results in a change of the operation state of a micrometer sized electronic device or material.

15.
Nat Commun ; 7: 13737, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27966536

RESUMO

Adaptive electronics, which are often referred to as memristive systems as they often rely on a memristor (memory resistor), are an emerging technology inspired by adaptive biological systems. Dissipative systems may provide a proper platform to implement an adaptive system due to its inherent adaptive property that parameters describing the system are optimized to maximize the entropy production for a given environment. Here, we report that a non-volatile and reversible adaptive microwave impedance memory device can be realized through the adaptive property of the dissipative structure of the driven ferromagnetic system. Like the memristive device, the microwave impedance of the device is modulated as a function of excitation microwave passing through the device. This kind of new device may not only helpful to implement adaptive information processing technologies, but also may be useful to investigate and understand the underlying mechanism of spontaneous formation of complex and ordered structures.

16.
Sci Rep ; 6: 39696, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-28004783

RESUMO

A high resolution imaging of the temperature and microwave near field can be a powerful tool for the non-destructive testing of materials and devices. However, it is presently a very challenging issue due to the lack of a practical measurement pathway. In this work, we propose and demonstrate experimentally a practical method resolving the issue by using a conventional CCD-based optical indicator microscope system. The present method utilizes the heat caused by an interaction between the material and an electromagnetic wave, and visualizes the heat source distribution from the measured photoelastic images. By using a slide glass coated by a metal thin film as the indicator, we obtain optically resolved temperature, electric, and magnetic microwave near field images selectively with a comparable sensitivity, response time, and bandwidth of existing methods. The present method provides a practical way to characterize the thermal and electromagnetic properties of materials and devices under various environments.

17.
Prog Transplant ; 12(1): 30-5, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11993067

RESUMO

CONTEXT: Rigorous candidate evaluation is paramount for estimating risk and long-term success with transplantation. In addition, because of increasing waiting times, patients are seeking listing at multiple centers or transferring waiting time from one center to another. Variations in center evaluation criteria are becoming increasingly important to patients. OBJECTIVE: To describe the similarities and differences among the evaluation guidelines for adult and pediatric kidney transplant programs in Missouri. DESIGN: A descriptive design was used. SETTING AND PARTICIPANTS: Kidney transplant nurse coordinators from 7 adult and 4 pediatric kidney transplant programs from 10 centers in Missouri were invited to submit the kidney transplant candidate evaluation guidelines from their programs. RESULTS: Guidelines were submitted by nurse coordinators from all programs. Consults with the kidney transplant team members, including surgeon, nephrologist, social worker, and nurse coordinator, were included in all of the programs. For the adult programs, 67% (20/30) of the tests and laboratory values were agreed on by at least 70% of the program transplant team members. Similarly, for the pediatric programs, 62% (16/26) of the age-appropriate tests and laboratory values were agreed on by at least 75% of the program transplant team members. CONCLUSIONS: Within the Missouri programs, testing is consistent whether the center is large or small, adult or pediatric. Transplant teams should periodically review their kidney transplant recipient evaluation criteria for similarities to and differences from the current state-of-the-science and surrounding programs.


Assuntos
Transplante de Rim/normas , Guias de Prática Clínica como Assunto/normas , Avaliação de Programas e Projetos de Saúde/normas , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Missouri
18.
Am J Manag Care ; 19(6): e238-48, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23844753

RESUMO

OBJECTIVES: To examine the influence of hospital competition on small-area inpatient resource use by payer. METHODS: We measured hospital competition and inpatient resource use using data from the 2008 Healthcare Cost and Utilization Project State Inpatient Databases. Generalized linear models adjusted for patient, population, and market characteristics were used to assess the relationship between inpatient resource use and hospital competition. RESULTS: Hospital competition had a similar influence on inpatient resource intensity for Medicare and privately insured patients. Hospitals in more competitive markets had significantly lower costs per discharge for both Medicare and privately insured patients. Hospital competition was not significantly associated with length of stay per discharge for either payer. CONCLUSION: Findings suggest that policies or incentives that promote or encourage competition in less competitive markets may reduce variation in resource use for both Medicare and private payers.


Assuntos
Competição Econômica , Recursos em Saúde/estatística & dados numéricos , Hospitalização/economia , Medicare , Adulto , Idoso , Bases de Dados Factuais , Economia Hospitalar , Humanos , Cobertura do Seguro/economia , Seguro Saúde/economia , Modelos Lineares , Medicare/economia , Pessoa de Meia-Idade , Análise de Pequenas Áreas , Estados Unidos
19.
Biosens Bioelectron ; 42: 326-31, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23208106

RESUMO

A near-field scanning microwave microscope (NSMM) is used to readout and visualize homemade 10-mer oligonucleotide microarrays and an Agilent 60-mer DNA microarray as a realistic test of NSMM applicability to multiplexed sequence analysis. Sensitive characterization of DNA coverage and high resolution mapping of DNA spots in the microarray were realized by measuring the change of microwave reflection coefficient (S11) at about 4 GHz operating frequency. Hybridization between target (free) and capture (immobilized) sequences leads to changes in the microwave reflection coefficient, which were measured by the NSMM. These changes are caused by hybridization-induced modification of the dielectric permittivity profile of the DNA film. The dynamic range based on analysis of the 10-mer microarrays is over 3 orders of magnitude with the detection limit estimated below 0.01 strands/µm². The NSMM method should be readily capable of detecting target coverages down to 98% of probe coverage. We also directly image the patterned DNA microarray by NSMM with a 2 µm resolution. The complementary optical image of the DNA microarray visualized by using a relative fluorescent intensity metric agrees well with the NSMM results.


Assuntos
Bioensaio , DNA/química , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência de DNA/métodos , Humanos , Limite de Detecção , Microscopia de Força Atômica , Micro-Ondas , Nanotecnologia , Hibridização de Ácido Nucleico
20.
J Biophotonics ; 6(2): 163-70, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22517728

RESUMO

We study the opto-electrical properties of Natronomonas pharaonis sensory rhodopsin II (NpSRII) by using a near-field microwave microprobe (NFMM) under external light illumination. To investigate the possibility of application of NFMM to biological macromolecules, we used time dependent properties of NPSRII before/after light activation which has three distinct states - ground-state, M-state, and O-state. The diagnostic ability of NFMM is demonstrated by measuring the microwave reflection coefficient (S(11)) spectrum of NpSRII under steady-state illumination in the wavelength range of 350-650 nm. Moreover, we present microwave reflection coefficient S(11) spectra in the same wavelength range for two fast-photocycling rhodopsins: green light-absorbing proteorhodopsin (GPR) and Gloeobacter rhodopsin (GR). In addition the frequency sweep shift can be detected completely even for tiny amounts of sample (∼10(-3) OD of rhodopsin). Based on these results NFMM shows both very high sensitivity for detecting conformational changes and produces a good time-resolved spectrum.


Assuntos
Micro-Ondas , Dispositivos Ópticos , Rodopsinas Microbianas/química , Halorrodopsinas/química , Halorrodopsinas/efeitos da radiação , Modelos Teóricos , Fenômenos Ópticos , Conformação Proteica , Estabilidade Proteica , Rodopsina/química , Rodopsina/efeitos da radiação , Rodopsinas Microbianas/efeitos da radiação , Rodopsinas Sensoriais/química , Rodopsinas Sensoriais/efeitos da radiação , Espectrofotometria
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