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1.
Nature ; 615(7950): 111-116, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36813962

RESUMEN

Many animals use Earth's magnetic field (also known as the geomagnetic field) for navigation1. The favoured mechanism for magnetosensitivity involves a blue-light-activated electron-transfer reaction between flavin adenine dinucleotide (FAD) and a chain of tryptophan residues within the photoreceptor protein CRYPTOCHROME (CRY). The spin-state of the resultant radical pair, and therefore the concentration of CRY in its active state, is influenced by the geomagnetic field2. However, the canonical CRY-centric radical-pair mechanism does not explain many physiological and behavioural observations2-8. Here, using electrophysiology and behavioural analyses, we assay magnetic-field responses at the single-neuron and organismal levels. We show that the 52 C-terminal amino acid residues of Drosophila melanogaster CRY, lacking the canonical FAD-binding domain and tryptophan chain, are sufficient to facilitate magnetoreception. We also show that increasing intracellular FAD potentiates both blue-light-induced and magnetic-field-dependent effects on the activity mediated by the C terminus. High levels of FAD alone are sufficient to cause blue-light neuronal sensitivity and, notably, the potentiation of this response in the co-presence of a magnetic field. These results reveal the essential components of a primary magnetoreceptor in flies, providing strong evidence that non-canonical (that is, non-CRY-dependent) radical pairs can elicit magnetic-field responses in cells.


Asunto(s)
Criptocromos , Drosophila melanogaster , Campos Magnéticos , Animales , Criptocromos/química , Criptocromos/metabolismo , Drosophila melanogaster/química , Drosophila melanogaster/citología , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiología , Flavina-Adenina Dinucleótido/metabolismo , Triptófano/metabolismo , Electrofisiología , Conducta Animal , Análisis de la Célula Individual , Neuronas/citología , Neuronas/metabolismo
2.
Immunity ; 49(4): 764-779.e9, 2018 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-30332632

RESUMEN

The major types of non-small-cell lung cancer (NSCLC)-squamous cell carcinoma and adenocarcinoma-have distinct immune microenvironments. We developed a genetic model of squamous NSCLC on the basis of overexpression of the transcription factor Sox2, which specifies lung basal cell fate, and loss of the tumor suppressor Lkb1 (SL mice). SL tumors recapitulated gene-expression and immune-infiltrate features of human squamous NSCLC; such features included enrichment of tumor-associated neutrophils (TANs) and decreased expression of NKX2-1, a transcriptional regulator that specifies alveolar cell fate. In Kras-driven adenocarcinomas, mis-expression of Sox2 or loss of Nkx2-1 led to TAN recruitment. TAN recruitment involved SOX2-mediated production of the chemokine CXCL5. Deletion of Nkx2-1 in SL mice (SNL) revealed that NKX2-1 suppresses SOX2-driven squamous tumorigenesis by repressing adeno-to-squamous transdifferentiation. Depletion of TANs in SNL mice reduced squamous tumors, suggesting that TANs foster squamous cell fate. Thus, lineage-defining transcription factors determine the tumor immune microenvironment, which in turn might impact the nature of the tumor.


Asunto(s)
Diferenciación Celular/inmunología , Regulación Neoplásica de la Expresión Génica/inmunología , Factores de Transcripción SOXB1/inmunología , Microambiente Tumoral/inmunología , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Diferenciación Celular/genética , Línea Celular Tumoral , Linaje de la Célula/genética , Linaje de la Célula/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Neutrófilos/inmunología , Neutrófilos/metabolismo , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Factor Nuclear Tiroideo 1/genética , Factor Nuclear Tiroideo 1/metabolismo , Microambiente Tumoral/genética
3.
PLoS Biol ; 21(9): e3002303, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37733664

RESUMEN

Optogenetic actuators have revolutionized the resolution at which biological processes can be controlled. In plants, deployment of optogenetics is challenging due to the need for these light-responsive systems to function in the context of horticultural light environments. Furthermore, many available optogenetic actuators are based on plant photoreceptors that might crosstalk with endogenous signaling processes, while others depend on exogenously supplied cofactors. To overcome such challenges, we have developed Highlighter, a synthetic, light-gated gene expression system tailored for in planta function. Highlighter is based on the photoswitchable CcaS-CcaR system from cyanobacteria and is repurposed for plants as a fully genetically encoded system. Analysis of a re-engineered CcaS in Escherichia coli demonstrated green/red photoswitching with phytochromobilin, a chromophore endogenous to plants, but also revealed a blue light response likely derived from a flavin-binding LOV-like domain. We deployed Highlighter in transiently transformed Nicotiana benthamiana for optogenetic control of fluorescent protein expression. Using light to guide differential fluorescent protein expression in nuclei of neighboring cells, we demonstrate unprecedented spatiotemporal control of target gene expression. We implemented the system to demonstrate optogenetic control over plant immunity and pigment production through modulation of the spectral composition of broadband visible (white) light. Highlighter is a step forward for optogenetics in plants and a technology for high-resolution gene induction that will advance fundamental plant biology and provide new opportunities for crop improvement.


Asunto(s)
Aracnodactilia , Optogenética , Nicotiana/genética , Escherichia coli/genética , Expresión Génica
4.
Liver Transpl ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38713020

RESUMEN

Psychiatric disorders after liver transplantation (LT) are associated with worse patient and graft outcomes, which may be amplified by inadequate treatment. We aimed to characterize the burden of psychiatric disorders, treatment patterns, and associated financial burden among liver transplantation recipients (LTRs). IQVIA PharMetrics (R) Plus for Academics-a large health plan claims database representative of the commercially insured US population-was used to identify psychiatric diagnoses among adult LTRs and assess treatment. Multivariable logistic regression analysis identified factors associated with post-LT psychiatric diagnoses and receipt of pharmacotherapy. Patient financial liability was estimated using adjudicated medical/pharmacy claims for LTRs with and without psychiatric diagnoses. Post-LT psychiatric diagnoses were identified in 395 (29.5%) of 1338 LTRs, of which 106 (26.8%) were incident cases. Treatment varied, with 67.3% receiving pharmacotherapy, 32.1% psychotherapy, 21.0% combination therapy, and 21.5% no treatment. Among 340 LTRs on psychotropic medications before transplant, 24% did not continue them post-LT. Post-LT psychiatric diagnoses were independently associated with female sex, alcohol-associated liver disease (ALD), prolonged LT hospitalization (>2 wk), and pre-LT psychiatric diagnosis. Incident psychiatric diagnoses were associated with female sex, ALD, and prolonged LT hospitalization. Patients with a post-LT psychiatric diagnosis had higher rates of hospitalization (89.6% vs. 81.5%, p <0.001) and financial liability (median $5.5K vs. $4.6K USD, p =0.006). Having a psychiatric diagnosis post-LT was independently associated with experiencing high financial liability >$5K. Over 1 in 4 LTRs had a psychiatric diagnosis in a large national cohort, yet nearly a quarter received no treatment. LTRs with psychiatric diagnoses experienced increased health care utilization and higher financial liability. Sociodemographic and clinical risk factors could inform high-risk subgroups who may benefit from screening and mitigation strategies.

5.
Phys Rev Lett ; 132(15): 150602, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38682995

RESUMEN

Multiphoton interference is at the heart of photonic quantum technologies. Arrays of integrated cavities can support bright sources of single photons with high purity and small footprint, but the inevitable spectral distinguishability between photons generated from nonidentical cavities is an obstacle to scaling. In principle, this problem can be alleviated by measuring photons with high timing resolution, which erases spectral information through the time-energy uncertainty relation. Here, we experimentally demonstrate that detection can be implemented with a temporal resolution sufficient to interfere photons detuned on the scales necessary for cavity-based integrated photon sources. By increasing the effective timing resolution of the system from 200 to 20 ps, we observe a 20% increase in the visibility of quantum interference between independent photons from integrated microring resonator sources that are detuned by 6.8 GHz. We go on to show how time-resolved detection of nonideal photons can be used to improve the fidelity of an entangling operation and to mitigate the reduction of computational complexity in boson sampling experiments. These results pave the way for photonic quantum information processing with many photon sources without the need for active alignment.

7.
Perception ; : 3010066241256221, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38778780

RESUMEN

Perceiving facial attractiveness is an important behaviour across psychological science due to these judgments having real-world consequences. However, there is little consensus on the measurement of this behaviour, and practices differ widely. Research typically asks participants to provide ratings of attractiveness across a multitude of different response scales, with little consideration of the psychometric properties of these scales. Here, we make psychometric comparisons across nine different response scales. Specifically, we analysed the psychometric properties of a binary response, a 0-100 scale, a visual analogue scale, and a set of Likert scales (1-3, 1-5, 1-7, 1-8, 1-9, 1-10) as tools to measure attractiveness, calculating a range of commonly used statistics for each. While certain properties suggested researchers might choose to favour the 1-5, 1-7 and 1-8 scales, we generally found little evidence of an advantage for one scale over any other. Taken together, our investigation provides consideration of currently used techniques for measuring facial attractiveness and makes recommendations for researchers in this field.

8.
PLoS Genet ; 17(7): e1009667, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34214072

RESUMEN

The ability to reproduce is essential in all branches of life. In metazoans, this process is initiated by formation of the germline, a group of cells that are destined to form the future gonads, the tissue that will produce the gametes. The molecular mechanisms underlying germline formation differs between species. In zebrafish, development of the germline is dependent on the specification, migration and proliferation of progenitors called the primordial germ cells (PGCs). PGC specification is dependent on a maternally provided cytoplasmic complex of ribonucleoproteins (RNPs), the germplasm. Here, we show that the conserved RNA-binding protein (RBP), Igf2bp3, has an essential role during early embryonic development and germline development. Loss of Igf2bp3 leads to an expanded yolk syncytial layer (YSL) in early embryos, reduced germline RNA expression, and mis-regulated germline development. We show that loss of maternal Igf2bp3 function results in translational de-regulation of a Nodal reporter during the mid-blastula transition. Furthermore, maternal igf2bp3 mutants exhibit reduced expression of germplasm transcripts, defects in chemokine guidance, abnormal PGC behavior and germ cell death. Consistently, adult igf2bp3 mutants show a strong male bias. Our findings suggest that Igf2bp3 is essential for normal embryonic and germline development, and acts as a key regulator of sexual development.


Asunto(s)
Células Germinativas/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Animales , Embrión no Mamífero/metabolismo , Desarrollo Embrionario/genética , Desarrollo Embrionario/fisiología , Proteínas de Unión al ARN/genética , Ribonucleoproteínas/metabolismo , Pez Cebra/genética , Proteínas de Pez Cebra/genética
9.
Microsurgery ; 44(1): e31105, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37675648

RESUMEN

BACKGROUND: The selection of reliable recipient vessels is essential for successful free tissue transfer. The use of internal mammary intercostal perforators (IMAPs), instead of the internal mammary vessels as the recipient vessels, has been described in breast reconstruction. Debates exist regarding the reliability of these perforators as recipient vessels because of their variability in location and caliber. The aim of this paper was to conduct a systematic literature review and meta-analysis to determine the reliability of the IMAPs as recipient vessels. METHODS: A systematic literature review was performed on the "PubMed," "Medline," "Ovid," and "Cochrane library" databases for articles published from January 1990 to March 2021. Exclusion criteria were non-English studies, reports with case number less than 5, cadaveric or animal studies, and studies with incomplete postoperative outcomes. The reliability of using IMAPs for breast reconstruction was determined by assessing the reported rates of partial or complete flap failure and other complications (fat necrosis, skin necrosis, and requirement for revision surgery). RESULTS: Three hundred and sixteen cases in 13 studies were included for further analysis with more than 85% of the IMAPs suitable for anastomosis being located in the second and third intercostal spaces. Partial or total flap failure was reported in three of 316 patients (0.95%). The rate of other complications such as fat necrosis, skin necrosis, and requirement for revision surgery were all less than 5%. CONCLUSION: With deliberate preoperative planning, delicate perioperative manipulation, and meticulous microvascular anastomosis, the internal mammary perforators can be used as reliable recipient vessels in microvascular breast reconstruction.


Asunto(s)
Necrosis Grasa , Mamoplastia , Arterias Mamarias , Humanos , Colgajos Quirúrgicos/irrigación sanguínea , Necrosis Grasa/etiología , Reproducibilidad de los Resultados , Arterias Mamarias/cirugía , Mamoplastia/efectos adversos , Complicaciones Posoperatorias/etiología
10.
Br J Cancer ; 129(1): 81-93, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37137996

RESUMEN

BACKGROUND: People with severe mental illness (SMI) are 2.5 times more likely to die prematurely from cancer in England. Lower participation in screening may be a contributing factor. METHODS: Clinical Practice Research Datalink data for 1.71 million, 1.34 million and 2.50 million adults were assessed (using multivariate logistic regression) for possible associations between SMI and participation in bowel, breast and cervical screening, respectively. RESULTS: Screening participation was lower among adults with SMI, than without, for bowel (42.11% vs. 58.89%), breast (48.33% vs. 60.44%) and cervical screening (64.15% vs. 69.72%; all p < 0.001). Participation was lowest in those with schizophrenia (bowel, breast, cervical: 33.50%, 42.02%, 54.88%), then other psychoses (41.97%, 45.57%, 61.98%), then bipolar disorder (49.94%, 54.35%, 69.69%; all p-values < 0.001, except cervical screening in bipolar disorder; p-value > 0.05). Participation was lowest among people with SMI who live in the most deprived quintile of areas (bowel, breast, cervical: 36.17%, 40.23%, 61.47%), or are of a Black ethnicity (34.68%, 38.68%, 64.80%). Higher levels of deprivation and diversity, associated with SMI, did not explain the lower participation in screening. CONCLUSIONS: In England, participation in cancer screening is low among people with SMI. Support should be targeted to ethnically diverse and socioeconomically deprived areas, where SMI prevalence is greatest.


Asunto(s)
Trastornos Mentales , Neoplasias del Cuello Uterino , Femenino , Adulto , Humanos , Detección Precoz del Cáncer , Estudios Transversales , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/complicaciones , Trastornos Mentales/epidemiología , Trastornos Mentales/complicaciones , Atención Primaria de Salud
11.
Liver Transpl ; 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38108824

RESUMEN

Liver transplantation (LT) is lifesaving for patients with cirrhosis; however, the resultant financial burden to patients has not been well characterized. We aimed to provide a nationally representative portrayal of patient financial burden after LT. Adult recipients of LT from 2006 to 2021 were identified using IQVIA PharMetrics® Plus for Academics-a large nationally representative claims database of commercially insured Americans. Patient financial liability (ie, what patients owe) was estimated using the difference between allowed and paid costs for adjudicated medical/pharmacy claims. Descriptive statistics were provided stratified by the financial liability group within 1 year after LT. Multivariable logistic regression modeling identified factors associated with high/extreme liability adjusting for covariates. Potential indirect costs of post-LT care were estimated based on hourly wages lost for care. Among 1412 recipients of LT, financial liability was heterogeneous-~3% had no liability and 21% had extreme liability > $10K for 1-year post-LT care; most (69%) paid between $1 and 10K, with 48% having liability >$5K. Factors associated with >$5K liability included older age, insurance/enrollment type, US region, history of HCC, and simultaneous liver-kidney transplant (for liability >$10K). Medication costs comprised ~30% of outpatient financial liability. Potential indirect costs from wages lost were $2,201-$6,073 per person, depending on an hourly wage. In a large national cohort of commercially insured recipients of LT, financial liability was highly variable across sociodemographic and clinical characteristics; nearly 1 out of 2 recipients of LT owed >$5K for 1 year of post-LT care. Transplant programs should help patients anticipate potential costs and identify vulnerable populations who would benefit from enhanced financial counseling.

12.
Br J Nutr ; 130(7): 1267-1277, 2023 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-36645103

RESUMEN

'Dietary variety' has been identified as a factor associated with food intake. Whilst this relationship may have longer-term benefits for body weight management when eating low-energy, nutrient-dense foods, it may increase the risk of overconsumption (and body adiposity) when foods are high energy density. This study sought to further explore pathways underpinning the relationship between dietary variety and body weight, by considering energy density as a moderating factor and portion size as a mediating factor in this relationship. Using prospective data from the UK Biobank, dietary variety scores (DVS), cumulative portion size and energy density were derived from 24-h dietary recall questionnaires at baseline and follow-up. BMI, whole-body fat percentage and fat-free mass were included as outcomes. Contrary to predictions, linear multiple regression models found some evidence of a negative, direct association between DVS and body weight outcomes at baseline (b = -0·13). Though dietary variety was significantly associated with larger portions across time points (b = 41·86-82·64), a moderated mediation effect was not supported at baseline or follow-up (Index ≤ 0·035). Taken together, these findings provide population-level evidence to support a positive association between variety and food intake, which in turn has potential implications for body weight management, both in terms of moderating food intake and benefitting diet quality.


Asunto(s)
Bancos de Muestras Biológicas , Tamaño de la Porción , Humanos , Índice de Masa Corporal , Estudios Prospectivos , Ingestión de Energía , Peso Corporal , Dieta , Reino Unido
13.
Conserv Biol ; : e14221, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37937455

RESUMEN

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium- to large-bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller-bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground-based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning.


Combinación de censos con fototrampas y mapas de extensión de la UICN para incrementar el conocimiento sobre la distribución de las especies Resumen Los mapas confiables de la distribución de las especies son fundamentales para la investigación y conservación de la biodiversidad. Los mapas de distribución de la Unión Internacional para la Conservación de la Naturaleza (UICN) están reconocidos como representaciones de autoridad de los límites geográficos de las especies, aunque no siempre se alinean con los datos actuales de su presencia. En los mapas recientes de área de hábitat (ADH), las áreas que no son hábitat han sido eliminadas de la distribución de la UICN para reducir los errores de comisión, pero su concordancia con la presencia actual de las especies tampoco ha sido analizada. Analizamos la concordancia entre la presencia registrada por los censos de fototrampas y pronosticamos la presencia a partir de los mapas de la UICN y de ADH de 510 especies de mamíferos de talla mediana a grande en 80 áreas de muestreo de fototrampas. Las cámaras detectaron sólo el 39% de las especies esperadas con base en la distribución de la UICN y los mapas de ADH en todas las áreas; el 85% de las disparidades con la UICN ocurrieron dentro de los 200 km a partir del borde de la distribución. Sólo el 4% de la presencia de las especies fue detectada por las cámaras ubicadas fuera de la distribución de la UICN. La probabilidad de disparidad entre las cámaras y la UICN fue significativamente mayor para los mamíferos de talla pequeña y para los especialistas de hábitat en las regiones Neotropical e Indomalaya y en áreas con doseles forestales más bajos. Nuestros hallazgos sugieren que los mapas de distribución y ADH pocas veces subrepresentan las áreas con presencia de las especies, pero con frecuencia pueden sobrerrepresentar la distribución al incluir áreas en donde las especies pueden estar ausentes, en particular los bordes de la distribución. Sugerimos que la combinación de los mapas de distribución con los sensores de biodiversidad en tierra, como las fototrampas, proporciona una base más rica de conocimiento para el mapeo y la planeación de la conservación.

14.
Behav Sleep Med ; 21(2): 117-128, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35317700

RESUMEN

OBJECTIVE: To examine the relationship between headaches, naps, and nocturnal sleep in women with chronic migraine (CM) using micro-longitudinal data from diaries and actigraphy. METHODS: 20 women with CM and 20 age and sex-matched healthy controls (HC) completed self-report questionnaires, electronic diaries, and wrist actigraphy over a 4-week period. Between-group comparisons were conducted with naps (frequency and duration) as the primary variable of interest. Within-group analyses were conducted on the CM group using hierarchical linear mixed models to examine the temporal relationships between headache severity, sleep behaviors, and sleep parameters. The primary variables of interest were naps (number and duration) and nocturnal sleep efficiency (diary and actigraphy). RESULTS: The CM group reported significantly more days with naps (25.85%) compared to the HC group (9.03%) during the study period (p = .0025). Within-group analyses in CM revealed that greater headache severity was associated with longer nap duration (p = .0037) and longer nap duration was associated with lower sleep efficiency measured using diaries (p = .0014) and actigraphy (p < .0001). CONCLUSIONS: Napping is more frequent in CM than HC and nap duration in CM is associated with headache severity and nocturnal sleep disturbance. These findings provide initial support for the hypothesis that daytime napping is a behavioral coping strategy used in CM that could contribute to insomnia.


Asunto(s)
Trastornos Migrañosos , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Femenino , Estudios Longitudinales , Sueño , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Actigrafía , Trastornos Migrañosos/complicaciones , Cefalea
15.
Proc Natl Acad Sci U S A ; 116(4): 1116-1125, 2019 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-30610174

RESUMEN

UVR8 is a plant photoreceptor protein that regulates photomorphogenic and protective responses to UV light. The inactive, homodimeric state absorbs UV-B light, resulting in dissociation into monomers, which are considered to be the active state and comprise a ß-propeller core domain and intrinsically disordered N- and C-terminal tails. The C terminus is required for functional binding to signaling partner COP1. To date, however, structural studies have only been conducted with the core domain where the terminal tails have been truncated. Here, we report structural investigations of full-length UVR8 using native ion mobility mass spectrometry adapted for photoactivation. We show that, while truncated UVR8 photoconverts from a single conformation of dimers to a single monomer conformation, the full-length protein exists in numerous conformational families. The full-length dimer adopts both a compact state and an extended state where the C terminus is primed for activation. In the monomer the extended C terminus destabilizes the core domain to produce highly extended yet stable conformations, which we propose are the fully active states that bind COP1. Our results reveal the conformational diversity of full-length UVR8. We also demonstrate the potential power of native mass spectrometry to probe functionally important structural dynamics of photoreceptor proteins throughout nature.


Asunto(s)
Proteínas de Arabidopsis/química , Proteínas Cromosómicas no Histona/química , Fotorreceptores de Plantas/química , Dominio Catalítico , Luz , Espectrometría de Masas/métodos , Proteínas de Plantas/química , Conformación Proteica , Rayos Ultravioleta
16.
J Econ Behav Organ ; 200: 1090-1104, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35822063

RESUMEN

Did individuals' experiences with the harms of the COVID-19 pandemic influence their attitudes towards safety-net programs? To assess this question, we combine rich information about county-level impacts and individual-level perceptions of the early pandemic, repeated measurements of attitudes towards safety-net expansion, and pre-pandemic measurements of related political attitudes. Individuals facing higher county-level impact or greater perceived risks are more likely to support long-term expansions to unemployment insurance and government-provided healthcare when surveyed in June 2020. These differences persist across time, with experiences in the early months of the pandemic remaining strongly predictive of attitudes towards safety-net expansion in early 2021.

17.
Phys Rev Lett ; 126(23): 230504, 2021 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-34170150

RESUMEN

Photons are natural carriers of high-dimensional quantum information, and, in principle, can benefit from higher quantum information capacity and noise resilience. However, schemes to generate the resources required for high-dimensional quantum computing have so far been lacking in linear optics. Here, we show how to generate GHZ states in arbitrary dimensions and numbers of photons using linear optical circuits described by Fourier transform matrices. Combining our results with recent schemes for qudit Bell measurements, we show that universal linear optical quantum computing can be performed in arbitrary dimensions.

18.
Cogn Psychol ; 126: 101387, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33964592

RESUMEN

Existing models of facial first impressions indicate between two and four factors that underpin all social trait judgements. Here, we submitted several large databases of these first impression ratings to unsupervised learning algorithms with the aim of clustering together faces, rather than traits, to examine the ways in which impressions may be grouped together. Experiment 1 revealed two clusters of faces that exist in both a full-dimensional, and two- or three-factor representations, of social impressions, while Experiment 2 indicated that these clusters also emerged in additional datasets. In Experiment 3, using Bayesian modelling approaches, we extracted the impression profile of each cluster and also derived a vector that maximally separated the clusters. The resulting vector related strongly to the valence and approachability components in existing models. In a further test of our model, we showed in Experiment 4 that mere facial appearance, rather than perceptions, is sufficient to separate these clusters, demonstrating probabilistically that facial cues like smiling may drive the perceptual profile that gives rise to the perceptual clusters. Finally, Experiment 5 showed that observer responses to faces in these two clusters mapped closely on to approach-avoidance behaviour, with observers responding rapidly and without instruction to approach faces from one cluster over the other. Taken together, our findings provide compelling evidence, drawing upon both computational and behavioural approaches, that existing models of social impressions are realised practically in terms of basic approach-avoidance mechanisms.


Asunto(s)
Juicio , Percepción Social , Teorema de Bayes , Señales (Psicología) , Humanos
19.
Nature ; 525(7568): 222-5, 2015 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-26322581

RESUMEN

Resonance fluorescence arises from the interaction of an optical field with a two-level system, and has played a fundamental role in the development of quantum optics and its applications. Despite its conceptual simplicity, it entails a wide range of intriguing phenomena, such as the Mollow-triplet emission spectrum, photon antibunching and coherent photon emission. One fundamental aspect of resonance fluorescence--squeezing in the form of reduced quantum fluctuations in the single photon stream from an atom in free space--was predicted more than 30 years ago. However, the requirement to operate in the weak excitation regime, together with the combination of modest oscillator strength of atoms and low collection efficiencies, has continued to necessitate stringent experimental conditions for the observation of squeezing with atoms. Attempts to circumvent these issues had to sacrifice antibunching, owing to either stimulated forward scattering from atomic ensembles or multi-photon transitions inside optical cavities. Here, we use an artificial atom with a large optical dipole enabling 100-fold improvement of the photon detection rate over the natural atom counterpart and reach the necessary conditions for the observation of quadrature squeezing in single resonance-fluorescence photons. By implementing phase-dependent homodyne intensity-correlation detection, we demonstrate that the electric field quadrature variance of resonance fluorescence is three per cent below the fundamental limit set by vacuum fluctuations, while the photon statistics remain antibunched. The presence of squeezing and antibunching simultaneously is a fully non-classical outcome of the wave-particle duality of photons.

20.
J Chem Phys ; 155(15): 154106, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34686059

RESUMEN

The emerging fields of citizen science and gamification reformulate scientific problems as games or puzzles to be solved. Through engaging the wider non-scientific community, significant breakthroughs may be made by analyzing citizen-gathered data. In parallel, recent advances in virtual reality (VR) technology are increasingly being used within a scientific context and the burgeoning field of interactive molecular dynamics in VR (iMD-VR) allows users to interact with dynamical chemistry simulations in real time. Here, we demonstrate the utility of iMD-VR as a medium for gamification of chemistry research tasks. An iMD-VR "game" was designed to encourage users to explore the reactivity of a particular chemical system, and a cohort of 18 participants was recruited to playtest this game as part of a user study. The reaction game encouraged users to experiment with making chemical reactions between a propyne molecule and an OH radical, and "molecular snapshots" from each game session were then compiled and used to map out reaction pathways. The reaction network generated by users was compared to existing literature networks demonstrating that users in VR capture almost all the important reaction pathways. Further comparisons between humans and an algorithmic method for guiding molecular dynamics show that through using citizen science to explore these kinds of chemical problems, new approaches and strategies start to emerge.


Asunto(s)
Ciencia Ciudadana , Gamificación , Simulación de Dinámica Molecular , Realidad Virtual , Algoritmos , Humanos
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