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1.
Int Microbiol ; 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33835333

RESUMO

Colpodella spp. are free-living flagellates closely related to the apicomplexans. Human infections by Colpodella sp. have been reported. A biflagellated trophozoite and cyst stage comprise the known life cycle stages of Colpodella sp. However, the process of encystation and excystation within the life cycle is unclear. Life cycle stages initiating human infections are unknown. We performed a detailed investigation of the life cycle of Colpodella sp. (ATCC 50594) in culture using Sam-Yellowe's trichrome stains and differential interference contrast (DIC) for light microscopy and fluorescence microscopy of Congo red-stained cells and investigated ultrastructure using transmission electron microscopy (TEM). We report previously undocumented stages of Colpodella sp. Asymmetric and asynchronous division was detected inside cysts by trichrome staining and by TEM. Odd-numbered juveniles and cysts containing more than four juvenile trophozoites were identified. Live imaging of active cultures captured the excystation and egress of juvenile trophozoites and confirmed the presence of multinucleate cysts. The ultrastructure of the multinucleate cyst is reminiscent of apicomplexan schizonts. Insights gained from the life cycle stages observed in culture allowed the construction of the life cycle of Colpodella sp. Knowledge of the life cycle will aid biochemical and molecular characterization of Colpodella sp. and help identify stages in human infections.

2.
Sci Rep ; 11(1): 7046, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33782488

RESUMO

Understanding the interactions among agricultural processes, soil, and plants is necessary for optimizing crop yield and productivity. This study focuses on developing effective monitoring and analysis methodologies that estimate key soil and plant properties. These methodologies include data acquisition and processing approaches that use unmanned aerial vehicles (UAVs) and surface geophysical techniques. In particular, we applied these approaches to a soybean farm in Arkansas to characterize the soil-plant coupled spatial and temporal heterogeneity, as well as to identify key environmental factors that influence plant growth and yield. UAV-based multitemporal acquisition of high-resolution RGB (red-green-blue) imagery and direct measurements were used to monitor plant height and photosynthetic activity. We present an algorithm that efficiently exploits the high-resolution UAV images to estimate plant spatial abundance and plant vigor throughout the growing season. Such plant characterization is extremely important for the identification of anomalous areas, providing easily interpretable information that can be used to guide near-real-time farming decisions. Additionally, high-resolution multitemporal surface geophysical measurements of apparent soil electrical conductivity were used to estimate the spatial heterogeneity of soil texture. By integrating the multiscale multitype soil and plant datasets, we identified the spatiotemporal co-variance between soil properties and plant development and yield. Our novel approach for early season monitoring of plant spatial abundance identified areas of low productivity controlled by soil clay content, while temporal analysis of geophysical data showed the impact of soil moisture and irrigation practice (controlled by topography) on plant dynamics. Our study demonstrates the effective coupling of UAV data products with geophysical data to extract critical information for farm management.

3.
Nat Commun ; 11(1): 6020, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243995

RESUMO

Understanding the structure and function of vasculature in the brain requires us to monitor distributed hemodynamics at high spatial and temporal resolution in three-dimensional (3D) volumes in vivo. Currently, a volumetric vasculature imaging method with sub-capillary spatial resolution and blood flow-resolving speed is lacking. Here, using two-photon laser scanning microscopy (TPLSM) with an axially extended Bessel focus, we capture volumetric hemodynamics in the awake mouse brain at a spatiotemporal resolution sufficient for measuring capillary size and blood flow. With Bessel TPLSM, the fluorescence signal of a vessel becomes proportional to its size, which enables convenient intensity-based analysis of vessel dilation and constriction dynamics in large volumes. We observe entrainment of vasodilation and vasoconstriction with pupil diameter and measure 3D blood flow at 99 volumes/second. Demonstrating high-throughput monitoring of hemodynamics in the awake brain, we expect Bessel TPLSM to make broad impacts on neurovasculature research.

4.
bioRxiv ; 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33083800

RESUMO

The sex discordance in COVID-19 outcomes has been widely recognized, with males generally faring worse than females and a potential link to sex steroids. A plausible mechanism is androgen-induced expression of TMPRSS2 and/or ACE2 in pulmonary tissues that may increase susceptibility or severity in males. This hypothesis is the subject of several clinical trials of anti-androgen therapies around the world. Here, we investigated the sex-associated TMPRSS2 and ACE2 expression in human and mouse lungs and interrogated the possibility of pharmacologic modification of their expression with anti-androgens. We found no evidence for increased TMPRSS2 expression in the lungs of males compared to females in humans or mice. Furthermore, in male mice, treatment with the androgen receptor antagonist enzalutamide did not decrease pulmonary TMPRSS2. On the other hand, ACE2 and AR expression was sexually dimorphic and higher in males than females. ACE2 was moderately suppressible with enzalutamide therapy. Our work suggests that sex differences in COVID-19 outcomes attributable to viral entry are independent of TMPRSS2. Modest changes in ACE2 could account for some of the sex discordance.

5.
Politics Life Sci ; 39(1): 101-117, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32697059

RESUMO

The past decade has seen a rapid increase in the number of studies employing psychophysiological methods to explain variation in political attitudes and behavior. However, the collection, analysis, and interpretation of physiological data present novel challenges for political scientists unfamiliar with the underlying biological concepts and technical skills necessary for utilizing this approach. Our objective in this article is to maximize the effectiveness of future work utilizing psychophysiological measurement by providing guidance on how the techniques can be employed most fruitfully as a complement to, not a replacement for, existing methods. We develop clear, step-by-step instructions for how physiological research should be conducted and provide a discussion of the issues commonly faced by scholars working with these measures. Our hope is that this article will be a useful resource for both neophytes and experienced scholars in lowering the start-up costs to doing this work and assessing it as part of the peer review process. More broadly, in the spirit of the open science framework, we aim to foster increased communication, collaboration, and replication of findings across political science labs utilizing psychophysiological methods.

7.
J Cataract Refract Surg ; 46(5): 774-777, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32358274

RESUMO

PURPOSE: To evaluate longitudinal power settings for optimally efficient lens fragment removal, using the Centurion machine. SETTING: John A. Moran Eye Center, University of Utah, Salt Lake City, USA. DESIGN: Experimental study. METHODS: Porcine lens nuclei were cut into 2.0 mm cubes. Experiments were conducted at 100% torsional power; vacuum set at 500 mm Hg, aspiration 50 mL/min, and intraocular pressure 110 mm Hg. A 20-degree tip with a 30-degree bevel was used. Longitudinal power was tested between 20% and 100%. Efficiency (time for fragment removal) and chatter (the number of times the fragment bounced from the tip) were measured. RESULTS: A linear increase in efficiency was observed from 20% to 100% longitudinal power (R = 0.9281, slope = -0.0271). An efficiency slope change occurred at 60% power, with the largest incremental change in efficiency between 20% and 60% (R = 0.9756, slope = -0.0394) and a lesser change between 60% and 100% (R = 0.9827, slope = -0.0121). Chatter analysis showed minimal events at 20% to 60%, but a significant increase at >80% (P = .005). This increase appeared to be incremental (R = 0.8929). CONCLUSIONS: Increasing longitudinal power, with all other settings constant, increased efficiency. Greatest efficiency gains were observed between 20% and 60%. At 80% and 100%, chatter events increased significantly. With a goal of recommending optimally efficient settings while minimizing excess energy and chatter, adding 60% of longitudinal power to 100% torsional power was shown to be the best setting to increase efficiency and avoid repulsion in these vacuum and aspiration settings.

8.
PLoS One ; 15(4): e0231476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324821

RESUMO

BACKGROUND: Emergency department based Physical Therapy (ED-PT) has been practiced globally in various forms for over 20 years and is an emerging resource in the US. While there is a growing body of evidence suggesting that ED-PT has a positive effect on a number of clinical and operational outcomes in patients presenting with musculoskeletal (MSK) pain, there are few published narratives that quantify this in the US. Although there are international papers that offer outcome data on reduction of pain, imaging, throughput time, and the ability of physical therapists to appropriately manage MSK conditions in the ED setting, most papers to date have been descriptive in nature. The purpose of this study is to assess the impact of ED-PT on imaging studies obtained, rates of opioids prescribed, and ED length of stay. METHODS: We prospectively identified patients presenting with musculoskeletal pain to an urban academic ED in Salt Lake City between January 2017 and June 2018. During the study, a physical therapist was in the ED three days (24 hours) per week and was available to evaluate and treat patients after consultation by the ED provider. We noted patient demographic information, imaging performed in the ED, medications administered and prescribed, and ED length of stay. We classified patients as those who received PT in the ED and those who did not and compared clinical outcomes between groups. We performed a subgroup analysis of patients presenting with low back pain and matched patients by age and gender. RESULTS: Over the 18-month study period, we identified 524 patients presenting to the ED with musculoskeletal pain. 381 (72.7%) received ED-initiated PT. The PT and non-PT groups were similar in average age (42.8 years vs. 45.1 years, p = 0.155), gender (% female: 53% vs. 46.9%, p-0.209), and primary presenting chief complaint (cervical, thoracic, or lumbar pain: 57.7% vs. 53.1%, p = 0.345). Patients who received PT had lower rates of imaging (38.3% vs. 51%, p = 0.009), ED opioid administration (17.5% vs. 32.9%, p<0.001), and a shorter average ED length of stay (4 hours vs. 6.2 hours, p<0.001). Rates of outpatient opioid prescriptions were similar between groups (16% vs. 21.7%, p = 0.129). In a subgroup analysis of patients presenting with low back pain, we found that PT patients had fewer imaging studies (PT 25% vs. non-PT 57%, p = 0.029) but found no difference in average ED length of stay (PT 3.7 hours vs. non-PT 4.6 hours, p = 0.21), opioid administration in the ED (PT 36% vs. non-PT 43%, P = 0.792), nor outpatient opioid administration (PT 17.9%. vs non-PT 17.9%, p = 1.0). CONCLUSION: In our experience, being seen by a physical therapist for MSK pain within the ED was associated with reduced use of imaging and time spent in the ED. Patients seeing a Physical Therapist were also less likely to receive an opioid prescription within the ED, a potentially significant finding given the need for opioid reduction strategies.


Assuntos
Dor Lombar/terapia , Dor Musculoesquelética/terapia , Adulto , Analgésicos Opioides/uso terapêutico , Serviço Hospitalar de Emergência , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Fisioterapeutas , Modalidades de Fisioterapia , Estudos Prospectivos , Encaminhamento e Consulta
9.
10.
Cell Death Dis ; 11(2): 152, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32102991

RESUMO

Glioblastoma (GBM) is the most prevalent primary malignant brain tumor and is associated with extensive tumor cell infiltration into the adjacent brain parenchyma. However, there are limited targeted therapies that address this disease hallmark. While the invasive capacity of self-renewing cancer stem cells (CSCs) and their non-CSC progeny has been investigated, the mode(s) of migration used by CSCs during invasion is currently unknown. Here we used time-lapse microscopy to evaluate the migratory behavior of CSCs, with a focus on identifying key regulators of migration. A head-to-head migration assay demonstrated that CSCs are more invasive than non-CSCs. Time-lapse live cell imaging further revealed that GBM patient-derived CSC models either migrate in a collective manner or in a single cell fashion. To uncover conserved molecular regulators responsible for collective cell invasion, we utilized the genetically tractable Drosophila border cell collective migration model. Candidates for functional studies were generated using results from a targeted Drosophila genetic screen followed by gene expression analysis of the human homologs in GBM tumors and associated GBM patient prognosis. This strategy identified the highly conserved small GTPase, Rap1a, as a potential regulator of cell invasion. Alteration of Rap1a activity impaired the forward progress of Drosophila border cells during development. Rap1a expression was elevated in GBM and associated with higher tumor grade. Functionally, the levels of activated Rap1a impacted CSC migration speed out of spheres onto extracellular matrix. The data presented here demonstrate that CSCs are more invasive than non-CSCs, are capable of both collective and single cell migration, and express conserved genes that are required for migration and invasion. Using this integrated approach, we identified a new role for Rap1a in the migration of GBM CSCs.

11.
J Forensic Sci ; 65(4): 1346-1349, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31999355

RESUMO

We were presented with the STR (short tandem repeat) profiles from two separate paternity trios. Each trio consisted of a mother, an alleged father, and products of conception (POC) that contained a hydatidiform mole but no visible fetus. In both cases, antecedent pregnancies had followed alleged sexual assaults. Mole classification and pathogenesis are described in order to explain the analyses and statistical reasoning used in each case. One mole exhibited several loci with two different paternal alleles, indicating it was a dispermic (heterozygous) mole. Maternal decidua contaminated the POC, preventing the identification of paternal obligate alleles (POAs) at some loci. The other mole exhibited only one paternal allele/locus at all loci and no maternal alleles, indicating it was a diandric and diploid (homozygous) mole. In each case, traditional calculations were used to determine paternity indices (PIs) at loci that exhibited one paternal allele/locus. PIs at mole loci with two different paternal alleles/locus were calculated from formulas first used for child chimeras that are always dispermic. Combined paternity indices in both mole cases strongly supported the paternity of each suspect.

12.
Int Microbiol ; 23(2): 303-311, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31748936

RESUMO

Colpodella species are free-living close relatives of apicomplexans that were recently reported to cause red blood cell infection in an immunocompromised human host and in a tick-borne human infection resulting in neurological symptoms. Unambiguous identification of the life cycle stages of Colpodella sp. using routine stains for light microscopy will aid rapid diagnosis in infections. Similarly, cells in culture and environmental samples can be rapidly identified by staining. Staining protocols are currently unavailable for cell detection by light microscopy. In this study, we investigated the feasibility of performing routine staining techniques for light microscopy for differentiating Colpodella sp. (ATCC 50594) and Bodo caudatus cysts in Hay medium cultures. We tested different basic and acidic dyes alone and in combination and also utilized a commercial trichrome staining protocol. The nonspecific fluorescent dye Calcofluor white was also evaluated. Staining times, dye concentrations, use of tap or distilled water rinses, use of a mordant and inclusion, or omission of decolorizers after staining were evaluated. We compared the intensity of color, clarity of morphological features, and cytoplasmic structures detected after staining. We report a new trichrome staining technique that allowed clear identification and differentiation of cyst stages of Colpodella sp. and B. caudatus. Immature Colpodella sp. cysts were identified as having an irregular, dual-colored (demilune), dark blue-purple and white appearance. Mature Colpodella sp. cysts stained dark red-blue and were identified in four-way mitotic division, while cysts of B. caudatus in diprotist or monoprotist (ATCC 30905) cultures were detected as spherical and red-pink in appearance.


Assuntos
Apicomplexa/isolamento & purificação , Compostos Azo , Amarelo de Eosina-(YS) , Verde de Metila , Coloração e Rotulagem/métodos , Animais , Benzenossulfonatos , Euglenozoários/isolamento & purificação , Humanos , Estágios do Ciclo de Vida
13.
Eur J Protistol ; 71: 125637, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31689662

RESUMO

In this study, we investigated morphological, immunological and molecular characteristics of Colpodella sp. (American Type Culture Collection 50594) in a diprotist culture containing Bodo caudatus as prey using Plasmodium rhoptry specific antibodies and oligonucleotide primers targeting Plasmodium falciparum rhoptry genes. In culture, Colpodella sp. attached to its prey using the apical end with attachment lasting for approximately 20 min while the cytoplasmic contents of the prey were aspirated into the posterior food vacuole of Colpodella sp. Encystment of Colpodella sp. was observed following feeding. Indirect immunofluorescence assay (IFA) and confocal microscopy using P. falciparum rhoptry specific antibodies showed intense reactivity with cytoplasmic vesicles of Colpodella sp. Bodo caudatus from diprotist and monoprotist (ATCC 30395) cultures showed weak background reactivity. Giemsa staining permitted differentiation of both protists. Genomic DNA isolated from the diprotist culture was used in polymerase chain reaction (PCR) with oligonucleotide primers targeting the P. falciparum rhoptry genes RhopH3, RhopH1/Clag3.2 and RAMA. Primers targeting exon 7 of the P. falciparum RhopH3 gene amplified an approximately 2 kb DNA fragment from the diprotist DNA template. DNA sequence and BLAST search analysis of the amplified product from diprotist DNA identified the RhopH3 gene demonstrating that the RhopH3 gene is conserved in Colpodella sp.


Assuntos
Alveolados/genética , Proteínas de Protozoários/genética , Sequência Conservada
14.
AIDS Behav ; 23(10): 2803-2815, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407211

RESUMO

Although young Black men who have sex with men (YBMSM) are disproportionately affected by HIV, they may be more heterogeneous as a group than is typically appreciated. Thus, the present study used a person-centered data-analytic approach to determine profiles of HIV-related risk among YBMSM and whether these profiles could be distinguished by age, HIV status, and socioeconomic risk (i.e., socioeconomic distress). YBMSM (N = 1808) aged 18 to 29 years completed a survey of sociodemographic characteristics, HIV status, and HIV-related behavioral and attitudinal factors (i.e., safer-sex self-efficacy, negative condom attitudes, being in difficult sexual situations, being in difficult sexual relationships, HIV treatment optimism, perceived HIV stigma). Latent profile analysis was used to identify HIV risk profiles and whether age, HIV status, and socioeconomic distress were associated with these profiles. Four profiles emerged: low-, medium-, and high-risk profiles, respectively, and a mixed profile characterized by a tendency to be in difficult sexual situations and relationships while also reporting high safer-sex self-efficacy and low negative attitudes toward condom use. Difficult sexual situations emerged as the key defining indicator of whether a profile reflected higher or lower risk. Younger age, being HIV-positive, and socioeconomic distress were associated with having a higher-risk profile. Given that unique risk profiles emerged that were differentially predicted by sociodemographic characteristics and HIV status, these findings have implications for tailoring interventions to the needs of different subgroups of YBMSM. Also, disempowering or risky sexual situations and relationships among YBMSM must be addressed.


Assuntos
Afro-Americanos/etnologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/etnologia , Assistência Centrada no Paciente , Profilaxia Pré-Exposição , Autoeficácia , Comportamento Sexual/estatística & dados numéricos , Estigma Social , Adolescente , Adulto , Afro-Americanos/psicologia , Preservativos/estatística & dados numéricos , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Homossexualidade Masculina/psicologia , Humanos , Masculino , Fatores de Risco , Sexo Seguro , Inquéritos e Questionários , Texas , Adulto Jovem
15.
Semin Diagn Pathol ; 36(5): 366-371, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31351825

RESUMO

Medicolegal liability is an issue of concern for all physicians, including pathologists. Identification of the key clinical issues that tend to lead to medical malpractice litigation, as well as the settlement values for such claims, can be useful for prospective risk management. This review analyzes medical malpractice claims filed in state and federal courts as published in legal databases. Additionally, this review also analyzes the reported settlement values for such claims.


Assuntos
Laboratórios , Imperícia/estatística & dados numéricos , Patologia Clínica , Padrão de Cuidado , Humanos , Inquéritos e Questionários
16.
Nat Commun ; 10(1): 2456, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31165732

RESUMO

Heat spontaneously flows from hot to cold in standard thermodynamics. However, the latter theory presupposes the absence of initial correlations between interacting systems. We here experimentally demonstrate the reversal of heat flow for two quantum correlated spins-1/2, initially prepared in local thermal states at different effective temperatures, employing a Nuclear Magnetic Resonance setup. We observe a spontaneous energy flow from the cold to the hot system. This process is enabled by a trade off between correlations and entropy that we quantify with information-theoretical quantities. These results highlight the subtle interplay of quantum mechanics, thermodynamics and information theory. They further provide a mechanism to control heat on the microscale.

17.
Hawaii J Med Public Health ; 78(6): 205-207, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31205817

RESUMO

This manuscript describes the efforts in research, education, and outreach of a unique partnership between the University of Hawai'i Cancer Center and the University of Guam in addressing cancer health disparities faced by Pacific Islanders in Hawai'i, Guam, and other parts of Micronesia. Significant accomplishments of this 15-year collaboration in research, training Micronesian students, and impact on the local communities are highlighted.


Assuntos
Pesquisa Biomédica , Institutos de Câncer , Disparidades em Assistência à Saúde , Neoplasias/etiologia , Grupo com Ancestrais Oceânicos/etnologia , Universidades , Pesquisa Biomédica/educação , Comportamento Cooperativo , Detecção Precoce de Câncer , Guam , Hawaii , Educação em Saúde , Humanos , Neoplasias/diagnóstico , Neoplasias/prevenção & controle
18.
AIDS Behav ; 23(9): 2361-2374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31016504

RESUMO

In contrast to intervention studies that assess psychosocial factors only as mediators or moderators of HIV risk, the present study assessed the effects of an Mpowerment-based community-level intervention on psychosocial determinants (e.g., depressive symptoms, sexual stigma) of HIV risk behavior among young black MSM. Approximately 330 respondents were surveyed annually for 4 years in each of two sites. General linear models examined change across time between the intervention and comparison communities, and participation effects in the intervention site. Social diffusion (spreading information within networks) of safer sex messages (p < 0.01) and comfort with being gay (p < 0.05) increased with time in intervention versus control. Cross-sectionally, intervention participants responded more favorably (p < 0.05) on social diffusion and depressive symptoms, but less favorably (p < 0.01) on sex in difficult situations and attitudes toward condom use. Findings suggest a need to address broader health issues of MSM as well as sexual risk.


Assuntos
Afro-Americanos/psicologia , Serviços de Saúde Comunitária/organização & administração , Infecções por HIV/etnologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/etnologia , Homossexualidade Masculina/psicologia , Poder Psicológico , Comportamento de Redução do Risco , Estigma Social , Adolescente , Adulto , Estudos Transversais , HIV , Infecções por HIV/psicologia , Promoção da Saúde , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Assunção de Riscos , Sexo Seguro , Autoeficácia , Comportamento Sexual/psicologia , Minorias Sexuais e de Gênero , Adulto Jovem
19.
J Pharm Biomed Anal ; 167: 1-6, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30731352

RESUMO

This manuscript presents a novel methodology for calculating the relative response factors (RRFs) of unstable degradation impurities of molibresib (1). The degradation impurities were observed by HPLC during stress testing and were accompanied by large mass balance deficits. However, the impurities could not be isolated for traditional RRF determination due to their instability. The RRFs of two degradation impurities were determined without isolation by multiple linear regression analysis of HPLC-UV data. The results permitted accurate quantification of the degradants. The benefits and drawbacks of the approach are discussed, including suggested validation acceptance criteria.


Assuntos
Benzodiazepinas/análise , Contaminação de Medicamentos , Modelos Teóricos , Benzodiazepinas/química , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Modelos Lineares , Análise Multivariada
20.
Phys Rev Lett ; 123(24): 240601, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31922824

RESUMO

Developments in the thermodynamics of small quantum systems envisage nonclassical thermal machines. In this scenario, energy fluctuations play a relevant role in the description of irreversibility. We experimentally implement a quantum heat engine based on a spin-1/2 system and nuclear magnetic resonance techniques. Irreversibility at a microscope scale is fully characterized by the assessment of energy fluctuations associated with the work and heat flows. We also investigate the efficiency lag related to the entropy production at finite time. The implemented heat engine operates in a regime where both thermal and quantum fluctuations (associated with transitions among the instantaneous energy eigenstates) are relevant to its description. Performing a quantum Otto cycle at maximum power, the proof-of-concept quantum heat engine is able to reach an efficiency for work extraction (η≈42%) very close to its thermodynamic limit (η=44%).

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