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1.
Br Poult Sci ; 65(4): 455-464, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38598261

RESUMEN

1. Tibial dyschondroplasia (TD) is a skeletal disorder in broilers that has financial implications, necessitating dietary modifications to reduce the prevalence of this disease. This study explored how arginine silicate inositol complex (ASI) supplementation affected tibial growth plate (TGP) and overall bone health in broilers with manganese (Mn) deficiency-induced TD.2. A total of 240 broiler chicks were divided into four groups, each consisting of 60 birds (15 replicates of four broilers each) as follows: i) Control, with 60 mg Mn per kg of diet; ii) ASI, with 60 mg Mn and 1 g ASI per kg of diet; iii) TD, with 22 mg Mn per kg of diet, and iv) TD+ASI, with 22 mg Mn and 1 g ASI per kg of diet.3. It was found that ASI supplementation increased tibial bone length in Mn-deficient TD broilers (p = 0.007). There was no Mn x ASI interaction for other bone morphometry variables (p > 0.05). However, both tibial bone mineral content and density were affected by Mn and ASI (p < 0.05). With ASI supplementation, serum bone-specific alkaline phosphatase and osteocalcin levels were elevated in the TD+ASI group compared to the TD group (p < 0.001). In the TD group, osteoprotegerin (OPG) levels in the TGP decreased compared to the control groups (p < 0.001).4. In contrast, ASI supplementation in the TD broilers counteracted the decrease in OPG compared to TD broilers without ASI supplementation (p < 0.001). The Mn level and ASI supplementation significantly influenced the OPG/receptor activator of the nuclear factor-κB ligand ratio (p < 0.001).5. In conclusion, the results demonstrated that inclusion of ASI in broiler diets could enhance bone formation variables by controlling OPG levels in the TGP, potentially serving as an effective method to decrease the occurrence of TD.


Asunto(s)
Alimentación Animal , Arginina , Pollos , Dieta , Suplementos Dietéticos , Inositol , Manganeso , Osteocondrodisplasias , Enfermedades de las Aves de Corral , Tibia , Animales , Pollos/crecimiento & desarrollo , Manganeso/administración & dosificación , Manganeso/metabolismo , Alimentación Animal/análisis , Suplementos Dietéticos/análisis , Osteocondrodisplasias/veterinaria , Osteocondrodisplasias/metabolismo , Tibia/efectos de los fármacos , Dieta/veterinaria , Arginina/administración & dosificación , Inositol/administración & dosificación , Masculino , Densidad Ósea/efectos de los fármacos , Silicatos/administración & dosificación , Distribución Aleatoria
2.
Br Poult Sci ; 62(2): 227-234, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33085516

RESUMEN

1. This work examined the effects of purified lycopene (LYC) supplementation or a source of LYC as tomato powder (TP) on productive performance, egg yolk cholesterol levels as well as gene expression related to mechanism and regulation of cholesterol.2. One hundred and fifty laying hens (Lohman LSL, hybrid) were randomly divided into one of three treatments, with 10 replicates of five hens per cage, totalling 50 hens per treatment. The hens were fed either a standard diet (control) or a standard diet supplemented with 20 mg purified lycopene/kg diet (LYC) or an equal amount of lycopene-containing tomato powder (TP) for 12 weeks.3. Feed consumption, egg production, and feed efficiency remained similar among treatments (P ≥ 0.27). Supplementing lycopene, either as a purified form or in TP, increased the levels of serum and egg yolk lycopene and reduced serum and egg yolk cholesterol concentrations (P < 0.001). Supplementation in either form decreased gene expression for intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but increased hepatic ABCG5 and ABCG8 (P < 0.001).4. The results of the present work revealed that egg yolk cholesterol metabolism is regulated by the modulation of a group of genes, particularly with LYC supplementation.


Asunto(s)
Pollos , Yema de Huevo , Alimentación Animal/análisis , Animales , Pollos/genética , Colesterol , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Expresión Génica , Licopeno , Óvulo
3.
Bratisl Lek Listy ; 121(6): 450-454, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32484711

RESUMEN

OBJECTIVE: Obesity induced by a high fat diet is associated with chronic up-regulation of inflammatory cytokines which stimulate osteoclast activity and bone resorption. However, the role of high-fat diet on bone-implant connectivity has not been studied in detail. In this study, we investigated whether a high-fat diet (HFD) affects bone implant connection (BIC) in periimplant bone. METHODS: Twenty female Sprague Dawley rats were divided in two groups: 1) Control rats were fed with normal chow and titanium implants were integrated into tibial bones at the end of 3rd month and no treatment was applied 2) HFD group; rats were fed a high-fat diet (42 % of calories as fat), then the titanium implants were integrated into tibial bones at the end 3rd month. Following surgical integration of the implants, the rats were fed with control and HFD diets for 3 months. After the 6 months experimental period all rats were sacrificed and the implants and surrounded bone tissues were collected and the BIC was assessed histomorphometrically after the non-decalcifiing histological methods. Bone implant connection was detected with the ratio of the implant surface directly connected with the peri-implant bone tissues to the total implant surface length. RESULTS: Histologic analysis showed that HFD was not impaired BIC (p>0.05). CONCLUSION: In conclusion, within the limitation of this research, HFD did not effect the BIC rat tibias (Tab. 2, Fig. 2, Ref. 26). Text in PDF www.elis.sk.


Asunto(s)
Trasplante Óseo , Dieta Alta en Grasa , Oseointegración , Animales , Huesos , Femenino , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie , Titanio
4.
Br Poult Sci ; 60(3): 195-201, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29355388

RESUMEN

1. The objective of this study was to determine muscle structure and gene expression in pectoralis major (p. major) muscle of broilers in response to deep pectoral myopathy (DPM) induction. 2. A total of 160 chickens from slow- and fast-growing broilers were raised under same conditions. Half of the broilers from each strain were encouraged to wing flap when they reached 2800 g body weight. Pectoralis minor (p. minor) muscle of the broilers was inspected for the occurrence of DPM and p. major samples were collected from broilers with or without DPM. The muscle fibre area and number, capillary number and the signalling pathways of vascular development (vascular endothelial growth factor A, VEGFA) and muscle contraction regulation (actin alpha 1, ACTA1; myosin light chain kinase 2, MYLK2 and ATPase Ca+2 transporting gene 1, ATP2A1) were studied in p. major muscle. 3. DPM induction increased fibre area of p. major muscle with a greater rate in the slow-growing strain compared with fast-growing line. Although the capillary number was higher in slow-growing compared with fast-growing broilers, in the case of DPM induction, the number of capillaries was similar between strains. 4. Expression of VEGFA, MYLK2 and ATP2A1 was greater in slow- than in fast-growing broilers. DPM induction increased expression of ACTA1, VEGFA and ATP2A1 in p. major muscle of broilers from both strains; however, MYLK2 expression was downregulated. 5. Changes in capillary density and expression of VEGFA found in the p. major muscle of broilers with DPM suggest increased blood flow to increase oxygen availability. The upregulation of ATP2A1 by DPM induction could be attributable to alterations in calcium ion transportation from the cytoplasm into the sarcoplasmic reticulum. 6. The results are evidence of changes in muscle structure and gene expression pathways in p. major muscle of broilers with DPM.


Asunto(s)
Proteínas Aviares/genética , Pollos , Expresión Génica , Enfermedades Musculares/veterinaria , Músculos Pectorales/química , Enfermedades de las Aves de Corral/fisiopatología , Animales , Proteínas Aviares/metabolismo , Enfermedades Musculares/genética , Enfermedades Musculares/fisiopatología , Músculos Pectorales/fisiopatología , Enfermedades de las Aves de Corral/genética
5.
Opt Express ; 25(7): 7839-7848, 2017 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-28380902

RESUMEN

We experimentally characterize a quantum photonic gate that is capable of converting multiqubit entangled states while acting only on two qubits. It is an important tool in large quantum networks, where it can be used for re-wiring of multipartite entangled states or for generating various entangled states required for specific tasks. The gate can be also used to generate quantum information processing resources, such as entanglement and discord. In our experimental demonstration, we characterized the conversion of a linear four-qubit cluster state into different entangled states, including GHZ and Dicke states. The high quality of the experimental results show that the gate has the potential of being a flexible component in distributed quantum photonic networks.

6.
Cell Mol Biol (Noisy-le-grand) ; 63(10): 93-98, 2017 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-29096748

RESUMEN

In this study, the effect of the supplemental organic chromium (Cr) forms on the expression of ovarian orexin(hypocretin), glucose transporters (GLUTs), heat shock proteins (HSPs) andnuclear factor-kappaB (NF-κB)were investigated in laying hens (HS). Laying hens (n=1800; 16-wk-old; Lohmann LSL-Lite) were allocated to 6 random groups according to a 2 × 3 factorial trial scheme with two different environmental temperatures [Thermoneutral (TN groups; at either 22±2 °C 24 h/d)  and heat stress (HS groups; at 34±2 °C for 8 h/d, 08:00 to 17:00 h, followed by 22°C for 16 h for a period of 12 wks)], andhens reared under both environmental conditions were fed either a basal diet or the basal diet supplemented with 1.600 mg of chromium-picolinate (CrPic, 12.43% Cr) and 0.788 mg of chromium-histidinate (CrHis, 25.22% Cr) per kg of diet, delivering 200 µg elemental Cr per kg diet. HS groups showed decreased levels of orexin and GLUTs(GLUT1, GLUT4), and increased NFκB, HSP60, HSP70 and HSP90 levels compared to the TN groups in ovarian tissue of hens (P < 0.0001 for all).However, dietary chromium supplementation (CrPic-CrHis) increasedorexin and GLUTs levels and significantly reduced the NF-κB and HSPs levels making them closer to those of thermoneutral group (P < 0.0001).In conclusion, CrPic and CrHis showed supported the relief and treatment of stress complications.


Asunto(s)
Pollos/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Histidina/análogos & derivados , Orexinas/metabolismo , Compuestos Organometálicos/farmacología , Ovario/metabolismo , Ácidos Picolínicos/farmacología , Regulación hacia Arriba/efectos de los fármacos , Animales , Suplementos Dietéticos , Femenino , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Proteínas de Choque Térmico/metabolismo , Histidina/farmacología , FN-kappa B/metabolismo , Orexinas/genética , Ovario/efectos de los fármacos , Estrés Fisiológico , Temperatura
7.
Br Poult Sci ; 58(2): 177-183, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27869499

RESUMEN

1. To examine the molecular mechanism of capsaicinoid supplementation from capsicum extract, laying Japanese quail (n = 180, 5 weeks old) were reared either at 22°C for 24 h/d (thermoneutral, TN) or at 34°C for 8 h/d (heat stress, HS) and fed on one of three diets containing 0, 25 or 50 mg of capsaicinoids per kilogram for 12 weeks (2 × 3 factorial arrangement). 2. The results revealed that exposure to HS decreased feed consumption by 10.7% and egg production by 13.6%, increased serum and ovary malondialdehyde (MDA) levels by 66.9% and 88.1%, respectively, and reduced ovary superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities by 28.3%, 48.7% and 43.8%, respectively. 3. There were magnifications in the ovary nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) levels by 42.4% and suppressions in nuclear factor (erythroid-derived 2)-like 2 (Nrf2), protein kinase B (Akt) and haem-oxygenase 1 (HO-1) levels by 29.2%, 38.2% and 30.7%, respectively, in heat-stressed quail. 4. With increasing supplemental capsaicinoids, there were linear increases in egg production, antioxidant enzyme activity, linear decreases in ovary MDA and NF-κB levels and linear increases in ovary Nrf2, Akt and HO-1 levels at a greater extent in quail reared under TN condition than those reared under HS condition. Two-way treatment interactions showed that the degree of restorations in all response variables was more notable under the HS environment than under the TN environment as supplemental capsaicinoid level was increased. 5. In conclusion, capsaicinoid supplementation alleviates oxidative stress through regulating the ovary nuclear transcription factors in heat-stressed quail.


Asunto(s)
Capsicum/química , Coturnix/fisiología , Suplementos Dietéticos , Calor/efectos adversos , Extractos Vegetales , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Femenino , Peroxidación de Lípido/fisiología , Oviposición/fisiología , Reproducción/fisiología , Estrés Fisiológico/fisiología
8.
Poult Sci ; 95(5): 1088-95, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26936958

RESUMEN

This study was conducted to evaluate the effects of dietary lycopene supplementation on growth performance, antioxidant status, and muscle nuclear transcription factor [Kelch like-ECH-associated protein 1 (Keap1) and (erythroid-derived 2)-like 2 (Nrf2)] expressions in broiler chickens exposed to heat stress (HS). A total of 180 one-day-old male broiler chicks (Ross 308) were assigned randomly to one of 2×3 factorially arranged treatments: two housing temperatures (22°C for 24 h/d; thermoneutral, TN or 34°C for 8 h/d HS) and three dietary lycopene levels (0, 200, or 400 mg/kg). Each treatment consisted of three replicates of 10 birds. Birds were reared to 42 d of age. Heat stress caused reductions in feed intake and weight gain by 12.2 and 20.7% and increased feed efficiency by 10.8% (P<0.0001 for all). Increasing dietary lycopene level improved performance in both environments. Birds reared under the HS environment had lower serum and muscle lycopene concentration (0.34 vs. 0.50 µg/mL and 2.80 vs. 2.13 µg/g), activities of superoxide dismutase (151 vs. 126 U/mL and 131 vs. 155 U/mg protein), glutathione peroxidase (184 vs. 154 U/mL and 1.39 vs. 1.74 U/mg protein), and higher malondialdehyde (MDA) concentration (0.53 vs. 0.83 µg/mL and 0.78 vs. 0.45 µg/ mg protein) than birds reared under the TN environment. Changes in levels of lycopene and MDA and activities of enzymes in serum and muscle varied by the environmental temperature as dietary lycopene level increased. Moreover, increasing dietary lycopene level suppressed muscle Keap1 expression and enhanced muscle Nrf2 expression, which had increased by 150% and decreased by 40%, respectively in response to HS. In conclusion, lycopene supplementation alleviates adverse effects of HS on performance through modulating expressions of stress-related nuclear transcription factors.


Asunto(s)
Antioxidantes/metabolismo , Carotenoides/farmacología , Pollos , Trastornos de Estrés por Calor/veterinaria , Enfermedades de las Aves de Corral/tratamiento farmacológico , Factores de Transcripción/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Trastornos de Estrés por Calor/metabolismo , Licopeno , Masculino , Factores de Transcripción/genética
9.
Opt Express ; 23(14): 17941-54, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26191854

RESUMEN

We propose a scheme for the distillation of partially entangled two-photon Bell and three-photon W states using metamaterials. The distillation of partially entangled Bell states is achieved by using two metamaterials with polarization dependence, one of which is rotated by π/2 around the direction of propagation of the photons. On the other hand, the distillation of three-photon W states is achieved by using one polarization dependent metamaterial and two polarization independent metamaterials. Upon transmission of the photons of the partially entangled states through the metamaterials the entanglement of the states increases and they become distilled. This work opens up new directions in quantum optical state engineering by showing how metamaterials can be used to carry out a quantum information processing task.

10.
Phys Rev Lett ; 115(3): 035502, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26230802

RESUMEN

Metamaterials have introduced a whole new world of unusual materials with functionalities that cannot be attained in naturally occurring material systems by mimicking and controlling the natural phenomena at subwavelength scales. However, the inherent absorption losses pose a fundamental challenge to the most fascinating applications of metamaterials. Based on a novel plasmon injection (PI or Π) scheme, we propose a coherent optical amplification technique to compensate losses in metamaterials. Although the proof of concept device here operates under normal incidence only, our proposed scheme can be generalized to an arbitrary form of incident waves. The Π scheme is fundamentally different from major optical amplification schemes. It does not require a gain medium, interaction with phonons, or any nonlinear medium. The Π scheme allows for loss-free metamaterials. It is ideally suited for mitigating losses in metamaterials operating in the visible spectrum and is scalable to other optical frequencies. These findings open the possibility of reviving the early dreams of making "magical" metamaterials from scratch.

11.
J Neurol Neurosurg Psychiatry ; 86(3): 265-72, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25121570

RESUMEN

BACKGROUND: Myelin oligodendrocyte glycoprotein (MOG) antibodies have been recently described in children with acute disseminating encephalomyelitis (ADEM), but the clinical and neuroradiological characterisation of this subgroup is lacking. OBJECTIVE: To compare the clinical and neuroradiological features of paediatric ADEM with and without MOG antibodies. METHODS: Clinical course, cerebrospinal fluid (CSF)-, MRI studies, outcome and MOG status of 33 paediatric ADEM prospectively studied were reviewed. RESULTS: MOG antibodies (median 1:2560; range 1:160-1:20 480) were detected in 19 children with ADEM. The majority of children showed a decline of serum MOG-IgG titres over time. Children with MOG antibodies did not differ in their age at presentation, sex ratio, the presence of oligoclonal bands, clinical symptoms or initial severity, apart from a higher CSF cell count (p=0.038), compared with children without MOG antibodies. In addition, further relapsing demyelinating episodes associated with MOG antibodies were observed only in children with MOG antibodies. All 19 children with MOG antibodies had a uniform MRI pattern, characterised by large, hazy and bilateral lesions and the absence of atypical MRI features (eg, mainly small lesions, well-defined lesions), which was significantly different compared to that of children without MOG antibodies (p=0.003; and p=0.032, respectively). In addition, children with MOG antibodies had involvement of more anatomical areas (p=0.035) including the myelon characterised by a longitudinally extensive transverse myelitis (p=0.003), more often a complete resolution of lesions (p=0.036) and a better outcome (p=0.038). CONCLUSIONS: Patients with ADEM with MOG antibodies in our cohort had a uniform MRI characterised by large, bilateral and widespread lesions with an increased frequency of longitudinal extensive transverse myelitis and a favourable clinical outcome in contrast to children lacking MOG antibodies.


Asunto(s)
Autoanticuerpos/sangre , Encefalomielitis Aguda Diseminada/diagnóstico , Encefalomielitis Aguda Diseminada/inmunología , Imagen por Resonancia Magnética , Glicoproteína Mielina-Oligodendrócito/inmunología , Adolescente , Encéfalo/inmunología , Encéfalo/patología , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Inmunoglobulina G/sangre , Masculino , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/inmunología , Mielitis Transversa/diagnóstico , Mielitis Transversa/inmunología , Neuromielitis Óptica/diagnóstico , Neuromielitis Óptica/inmunología , Pronóstico , Estudios Prospectivos , Médula Espinal/inmunología , Médula Espinal/patología
12.
Br Poult Sci ; 56(2): 247-54, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25622754

RESUMEN

An experiment was conducted to evaluate the effects of a histidine complex of chromium (chromium histidinate, CrHis) on egg production, lipid peroxidation and the expression of hepatic nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and heat-shock proteins (HSPs) in Japanese quails (Coturnix coturnix japonica) exposed to heat stress (HS). A total of 180 5-week-old female quails were reared either at 22°C for 24 h/d (thermoneutral, TN) or 34°C for 8 h/d (heat stress, HS) for 12 weeks. Birds in both environments were randomly given one of three diets: basal diet and basal diet supplemented with 400 or 800 µg of elemental Cr as CrHis per kg of diet. Blood, egg yolk and liver samples collected at the end of the trial were analysed to determine concentrations of cholesterol and malondialdehyde (MDA) and expressions of transcription and heat-shock proteins. Exposure to HS caused reductions in feed intake (-8.1%) and egg production (-15.8%), elevations in serum (14.8%) and egg-yolk (29.0%) cholesterol concentrations, decreases in serum (113%) and egg-yolk (73.0%) MDA concentrations and increases in the expressions of hepatic NF-κB (52.3%) and HSPs (averaging 53.6%). The effects of increasing supplemental CrHis on the response variables were more notable in the HS environment than in the TN environment. There were considerable improvements in feed intake and egg production, decreases in serum and egg-yolk cholesterol concentrations and suppressions in the expressions of hepatic nuclear protein and HSPs in response to increasing supplemental CrHis concentration in the diet of quails reared under the HS environment. In conclusion, supplemental CrHis improves productivity through alleviating oxidative stress and modulating the expressions of hepatic NF-κB and HSPs in heat-stressed quails.


Asunto(s)
Coturnix/genética , Coturnix/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Choque Térmico/genética , Histidina/análogos & derivados , FN-kappa B/genética , Compuestos Organometálicos/farmacología , Estrés Oxidativo/efectos de los fármacos , Alimentación Animal/análisis , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Proteínas de Choque Térmico/metabolismo , Respuesta al Choque Térmico/efectos de los fármacos , Histidina/metabolismo , Histidina/farmacología , FN-kappa B/metabolismo , Compuestos Organometálicos/metabolismo , Distribución Aleatoria
13.
Bratisl Lek Listy ; 116(10): 587-90, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26531868

RESUMEN

AIM: The aim of this study was to investigate the effect of oxidative stress on nucleosome levels and its relation with the clinical features in schizophrenia patients. MATERIAL AND METHOD: Thirty schizophrenia patients and 30 healthy controls were enrolled in this study. Patients were diagnosed with schizophrenia according to the 4th edition of the Diagnostic and Statistical Manual for Mental Disorders (DSM-IV). The control group consisted of 30 healthy subjects matched to the patients with regard to age and gender and who had no history of any psychiatric disorder. The severity of schizophrenia symptoms in the patients was evaluated using the Positive and Negative Syndrome Scale (PANSS) and the Clinical Global Impression Severity Scale (CGI-S). Physical and neurological examinations were performed in each of the patients and controls. RESULTS: Nucleosome, total oxidant levels and OSI values were higher in schizophrenia patients than in controls (p<0.05). There was no significant difference in the total antioxidant levels. There was a positive correlation between the nucleosome level and PANSS positive subscale (p=0.028, r=0.402). There was a positive correlation between TAS and age (p=0.025, r=0.289), PANSS total (p<0.001, r=0.604). There was a negative correlation between OSI and PANSS total (p=0.019, r=-0.427), PANSS positive subscale (p=0.043, r=-0.372). There was a negative correlation between TOS and PANS total (p=0.028, r=-0.402). CONCLUSION: In this study we found a correlation between nucleosome level and PANSS positive subscale. To our knowledge, this is the first study that evaluates oxidative stress and nucleosomes released from apoptotic cells together (Tab. 2, Ref. 50).


Asunto(s)
Nucleosomas/metabolismo , Estrés Oxidativo/fisiología , Esquizofrenia/genética , Adulto , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica , Esquizofrenia/sangre , Esquizofrenia/diagnóstico
14.
Science ; 384(6700): 1122-1126, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38843319

RESUMEN

The control of thermal radiation by shaping its spatial and spectral emission characteristics plays a key role in many areas of science and engineering. Conventional approaches to tailoring thermal emission using metamaterials are hampered both by the limited spatial resolution of the required subwavelength material structures and by the materials' strong absorption in the infrared. In this work, we demonstrate an approach based on the concept of topology. By changing a single parameter of a multilayer coating, we were able to control the reflection topology of a surface, with the critical point of zero reflection being topologically protected. The boundaries between subcritical and supercritical spatial domains host topological interface states with near-unity thermal emissivity. These topological concepts enable unconventional manipulation of thermal light for applications in thermal management and thermal camouflage.

15.
Light Sci Appl ; 13(1): 143, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38918396

RESUMEN

Quantum heat engines and refrigerators are open quantum systems, whose dynamics can be well understood using a non-Hermitian formalism. A prominent feature of non-Hermiticity is the existence of exceptional points (EPs), which has no counterpart in closed quantum systems. It has been shown in classical systems that dynamical encirclement in the vicinity of an EP, whether the loop includes the EP or not, could lead to chiral mode conversion. Here, we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs (LEPs), which include the effects of quantum jumps and associated noise-an important quantum feature not present in previous works. We demonstrate, using a Paul-trapped ultracold ion, the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an LEP. We witness the cycling direction to be associated with the chirality and heat release (absorption) of the quantum heat engine (quantum refrigerator). Our experiments have revealed that not only the adiabaticity breakdown but also the Landau-Zener-Stückelberg process play an essential role during dynamic encircling, resulting in chiral thermodynamic cycles. Our observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

16.
Opt Express ; 21(18): 20601-10, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-24103932

RESUMEN

With extremely low material absorption and exceptional surface smoothness, silica-based optical resonators can achieve extremely high cavity quality (Q) factors. However, the intrinsic material limitations of silica (e.g., lack of second order nonlinearity) may limit the potential applications of silica-based high Q resonators. Here we report some results in utilizing layer-by-layer self-assembly to functionalize silica microspheres with nonlinear and plasmonic nanomaterials while maintaining Q factors as high as 10(7). We compare experimentally measured Q factors with theoretical estimates, and find good agreement.

17.
Nano Lett ; 12(5): 2504-8, 2012 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-22452310

RESUMEN

Heralded single surface plasmon polaritons are excited using photons generated via spontaneous parametric down conversion. The mean excitation rates, intensity correlations, and Fock state populations are studied. The observed dependence of the second-order coherence in our experiment is consistent with a linear uncorrelated Markovian environment in the quantum regime. Our results provide important information about the effect of loss for assessing the potential of plasmonic waveguides for future nanophotonic circuitry in the quantum regime.

18.
Br Poult Sci ; 54(4): 447-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23906218

RESUMEN

1. The aim of the study was to describe the effect of Epigallocatechin-3-gallate (EGCG), a polyphenol derived from green tea, on activator protein-1 (AP-1) components (phospho-c-Jun and c-Fos), cyclooxygenase-2 (COX-2) and heat shock proteins (HSPs) in the liver of heat-stressed quails. 2. A total of 180 5-week-old female Japanese quails were reared either at 22°C for 24 h/d (thermoneutral, TN) or 34°C for 8 h/d (heat stress, HS) for 12 weeks. Birds in both environments were randomly given 1 of 3 diets: basal diet and basal diet with 200 or 400 mg of EGCG added per kilogram of diet. 3. The hepatic c-Jun, c-Fos, COX-2 and HSPs gene expression for quails reared under the HS environment was greater than those reared under the TN environment. Supplemental EGCG decreased hepatic expression of these proteins at a greater extent under HS than TN. 4. In conclusion, suppression of AP-1 COX-2 and HSPs may partly account for the inhibitory effect of EGCG in heat-stressed quail.


Asunto(s)
Antioxidantes/metabolismo , Catequina/análogos & derivados , Coturnix/fisiología , Respuesta al Choque Térmico/efectos de los fármacos , Hígado/metabolismo , Alimentación Animal/análisis , Animales , Anticuerpos , Antioxidantes/administración & dosificación , Catequina/administración & dosificación , Catequina/metabolismo , Pollos , Coturnix/crecimiento & desarrollo , Ciclooxigenasa 2/metabolismo , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Femenino , Proteínas de Choque Térmico/metabolismo , Hígado/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Factor de Transcripción AP-1/metabolismo
19.
Br Poult Sci ; 54(5): 620-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23957289

RESUMEN

1. The herb Creeping Thistle, Cirsium arvense (C. arvense), has been used in folk medicine due to its antioxidant and anti-inflammatory effects. 2. The aim of this study was to investigate the effects of dietary C. arvense extract supplementation on performance, egg quality, nutrient digestibility and antioxidant status in quail. 3. Quails (n = 150) were allocated randomly to one of the three dietary treatments: basal diet and basal diet enriched with 100 and 200 mg C. arvense extract per kg diet. 4. Dietary enrichment with C. arvense extract altered neither performance and egg quality parameters nor nutrient digestibility. Although there were no changes in concentrations of vitamin A and E in serum, liver and egg yolk, supplemental C. arvense extract decreased MDA concentrations in serum, liver and egg yolk by 39.3, 40.5 and 51.5%, respectively, in a dose-response manner. As supplemental C. arvense extract increased to 200 mg/kg, the activity of hepatic SOD, CAT and GSH-Px increased by 14.5, 17.4 and 35.5%, respectively. 5. Addition of C. arvense extract up to 200 mg to per kg diet enhanced antioxidant status in laying quail and their eggs, without affecting performance and other egg quality parameters. 6. Future studies are needed to elucidate the mechanism behind the antioxidant effects of C. arvense extract.


Asunto(s)
Cirsium/metabolismo , Coturnix/metabolismo , Suplementos Dietéticos/normas , Huevos/análisis , Extractos Vegetales/farmacología , Animales , Catalasa/análisis , Femenino , Glutatión Peroxidasa/análisis , Malondialdehído/sangre , Extractos Vegetales/administración & dosificación , Distribución Aleatoria , Superóxido Dismutasa/análisis , Vitamina A/sangre , Vitamina E/sangre
20.
Nat Commun ; 14(1): 2076, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37045822

RESUMEN

Nontrivial spectral properties of non-Hermitian systems can lead to intriguing effects with no counterparts in Hermitian systems. For instance, in a two-mode photonic system, by dynamically winding around an exceptional point (EP) a controlled asymmetric-symmetric mode switching can be realized. That is, the system can either end up in one of its eigenstates, regardless of the initial eigenmode, or it can switch between the two states on demand, by simply controlling the winding direction. However, for multimode systems with higher-order EPs or multiple low-order EPs, the situation can be more involved, and the ability to control asymmetric-symmetric mode switching can be impeded, due to the breakdown of adiabaticity. Here we demonstrate that this difficulty can be overcome by winding around exceptional curves by additionally crossing diabolic points. We consider a four-mode [Formula: see text]-symmetric bosonic system as a platform for experimental realization of such a multimode switch. Our work provides alternative routes for light manipulations in non-Hermitian photonic setups.

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