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1.
Foods ; 12(6)2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36981111

RESUMEN

The evolution of quality attributes and their association with the protein properties of lightly tilapias fillets salted with different replacement proportions of NaCl with KCl (0%, 10%, 30%, 50%, 70%, 100%) at the same ionic strength were investigated. KCl replacements using optimal substitution (50% of KCl) contributed to maintaining desired quality properties. Further, KCl replacement (about 50~70% of KCl) led to the insolubilization and weakened stability of myofibrillar proteins, represented by the unfolding of the myofibrillar protein, increased surface hydrophilic points, and strengthened internal protein-protein interaction, resulting in the structurally reinforced hardness and lower water-holding capacity. Excessive replacement (more than 70% of KCl) showed apparent deterioration in taste quality, coloration, and hardness received by sensory sensation caused by immoderate hydrolysis and aggravated oxidation of the myofibrillar protein. In this sense, insights into KCl replacements on protein properties might be a positive approach to improving quality attributes of lightly salted tilapias fillets.

2.
Food Sci Nutr ; 11(2): 1013-1023, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36789073

RESUMEN

In this study, dry-cured Spanish mackerel (Scomberomorus niphonius, DCSM) was prepared via three different methods (hot-air drying, cold-air drying, and sun drying). The content of 4-hydroxy-2-hexenal (HHE) and 4-hydroxy-2-nonenal (HNE) derived from lipid oxidation in whole processes was investigated by HPLC-MS/MS. The changes in fatty acid composition were detected by GC-MS, and the degree of lipid oxidation was evaluated by the levels of acid values (AV), peroxide values (POV), and thiobarbituric acid-reactive substances (TBARS). The results showed that the drying process significantly accelerated lipid oxidation in DCSM. The contents of HHE and HNE were significantly increased after processing. The content of HHE was higher by 18.44-, 13.45-, and 16.32-folds compared with that of HNE after three different processes, respectively. The HHE and HNE contents fluctuated upward during the hot-air and cold-air drying process. However, the contents of HHE and HNE increased time-dependent during the sun drying process, with the highest values of 86.33 ± 10.54 and 5.29 ± 0.54 mg/kg fish among the three different processes. Besides, there was a significant positive correlation between HHE contents and n-3 fatty acids content in hot-air drying and sun drying processes (Pearson's r = .991/.996), and HNE occurrence was closely related to n-6 fatty acid content in sun drying process (Pearson's r = .989). Regression analysis indicated that the content of HHE and TOTOXTBA values in DCSM showed good linear relationships (R 2 value = .907), which suggested that the content of HHE could be used to estimate the oxidative deterioration of dry-cured fish products.

3.
Phys Rev Lett ; 129(24): 243402, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36563247

RESUMEN

We report the creation of a shell BEC in the presence of Earth's gravity with immiscible dual-species BECs of sodium and rubidium atoms. After minimizing the displacement between the centers of mass of the two BECs with a magic-wavelength optical dipole trap, the interspecies repulsive interaction ensures the formation of a closed shell of sodium atoms with its center filled by rubidium atoms. Releasing the double BEC together from the trap, we observe explosion of the filled shell accompanied by energy transfer from the inner BEC to the shell BEC. With the inner BEC removed, we obtain a hollow shell BEC that shows self-interference as a manifestation of implosion. Our results pave an alternative way for investigating many of the intriguing physics offered by shell BECs.

4.
Phys Rev Lett ; 128(22): 223201, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35714238

RESUMEN

Ultracold polar molecules (UPMs) are emerging as a novel and powerful platform for fundamental applications in quantum science. Here, we report characterization of the coherence between nuclear spin levels of ultracold ground-state sodium-rubidium molecules loaded into a 3D optical lattice with a nearly photon scattering limited trapping lifetime of 9(1) seconds. After identifying and compensating the main sources of decoherence, we achieve a maximum nuclear spin coherence time of T_{2}^{*}=3.3(6) s with two-photon Ramsey spectroscopy. Furthermore, based on the understanding of the main factor limiting the coherence of the two-photon Rabi transition, we obtain a Rabi line shape with linewidth below 0.8 Hz. The simultaneous realization of long lifetime and coherence time, and ultrahigh spectroscopic resolution in our system unveils the great potentials of Ultracold polar molecules in quantum simulation, computation, and metrology.

5.
Phys Rev Lett ; 127(16): 163401, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34723573

RESUMEN

We probe photoinduced loss for chemically stable bosonic ^{23}Na^{87}Rb and ^{23}Na^{39}K molecules in chopped optical dipole traps, where the molecules spend a significant time in the dark. We expect the effective two-body decay to be significantly suppressed due to the small expected complex lifetimes of about 13 and 6 µs for ^{23}Na^{87}Rb and ^{23}Na^{39}K, respectively. However, instead we do not observe any suppression of the two-body loss in parameter ranges where large loss suppressions are expected. We believe these unexpected results are most probably due to drastic underestimation of the complex lifetime by at least 1-2 orders of magnitude.

6.
Curr Biol ; 31(22): 4887-4897.e5, 2021 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-34551283

RESUMEN

Large mammalian carnivores have undergone catastrophic declines during the Anthropocene across the world. Despite their pivotal roles as apex predators in food webs and ecosystem dynamics, few detailed dietary datasets of large carnivores exist, prohibiting deep understanding of their coexistence and persistence in human-dominated landscapes. Here, we present fine-scaled, quantitative trophic interactions among sympatric carnivores from three assemblages in the Mountains of Southwest China, a global biodiversity hotspot harboring the world's richest large-carnivore diversity, derived from DNA metabarcoding of 1,097 fecal samples. These assemblages comprise a large-carnivore guild ranging from zero to five species along with two mesocarnivore species. We constructed predator-prey food webs for each assemblage and identified 95 vertebrate prey taxa and 260 feeding interactions in sum. Each carnivore species consumed 6-39 prey taxa, and dietary diversity decreased with increased carnivore body mass across guilds. Dietary partitioning was more evident between large-carnivore and mesocarnivore guilds, yet different large carnivores showed divergent proportional utilization of different-sized prey correlating with their own body masses. Large carnivores particularly selected livestock in Tibetan-dominated regions, where the indigenous people show high tolerance toward wild predators. Our results suggest that dietary niche partitioning and livestock subsidies facilitate large-carnivore sympatry and persistence and have key implications for sustainable conservation promoting human-carnivore coexistence.


Asunto(s)
Carnívoros , Ganado , Animales , Biodiversidad , Ecosistema , Cadena Alimentaria , Humanos , Conducta Predatoria
7.
Am J Transl Res ; 13(6): 6654-6661, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34306409

RESUMEN

OBJECTIVE: To explore the effect of multidisciplinary collaborative continuous nursing on the psychological state and quality of life of cervical cancer patients. METHODS: A total of 132 patients with cervical cancer who were hospitalized in our hospital were selected as the research subjects, and they were randomized into the observation group (n=66) and the control group (n=66). The control group was given regular continuous nursing, while the observation group was given three-month multidisciplinary collaborative continuous nursing. It was conducted through WeChat, telephone follow-up, face-to-face consultation and lectures, giving guidance on diet, medication, pain control, psychological health, self-care, review time, recognition and processing of postoperative complications, daily activities, social behaviors and so on. Patients' anxiety, depression, quality of life, cancer-related fatigue, complication incidence, and sleep quality were compared between the two groups. RESULTS: Self-rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) were applied for evaluation. The anxiety and depression scores of patients in the observation group were significantly lower than those in the control group (both P<0.001). The scores on physical functioning, general health, social role functioning, emotional role functioning, and mental health, in the observation group were higher than those in the control group (all P<0.01). Compared with patients in the control group, those in the observation group had higher scores on behavioral/severity, affective meaning, sensory and cognition/mood (all P<0.001). Patients in the observation group had lower complication incidence of postoperative nausea, abdominal pain, wound infection and intestinal obstruction (P<0.05). Besides, the sleep quality scores of patients in the observation group were also lower than those in the control group (all P<0.001). CONCLUSION: The application of multidisciplinary collaborative continuous nursing for patients with cervical cancer is effective. It can improve patients' depression, anxiety, quality of life, cancer-related fatigue, sleep quality, and reduce the incidence of complications. Therefore, it is worthy of clinical application and promotion.

8.
J Hazard Mater ; 403: 123806, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33264908

RESUMEN

3D interconnected porous N-doped carbocatalyst derived from the waste air-laid paper plays as an efficient metal-free catalyst for H2S removal in super-Claus reaction. The honeycomb-like porous nitrogen-doped carbons are fabricated through a facile impregnation of alkaline solution and NH3 post-treatment method. The experiments prove that NH3 post-treatment is an efficient way to improve the catalytic performance, which resulting in outstanding reactivity and stability with highest sulfur formation rate of 496.6 gsulfurkgcat.-1 h-1 and sulfur yield of 86.7 % in feed gas with high concentration (ca. 10,000 ppm) of H2S for selective oxidation. Significantly, the optimized pyridinic-N content and defect degree endow the N-doped porous carbon (NPC700) with highest catalytic activity according to the Raman and XPS results. The high surface area and abundant porous structure also contribute to the high catalytic performance by increasing the exposure degree of active site and offering additional active surface. Based on the XPS, SEM, TEM and EDS mapping results, the N-doped porous carbon are proved to be stable catalysts since the morphology and surface chemical environment remain similar after the oxidative desulfurization process.

9.
Nat Ecol Evol ; 4(10): 1327-1331, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32747773

RESUMEN

As both a flagship and umbrella species, the giant panda (Ailuropoda melanoleuca) is one of the most heavily invested species in conservation. Here, we report the wide distribution range retreat of the leopard (Panthera pardus, 81% loss), snow leopard (P. uncia, 38%), wolf (Canis lupus, 77%) and dhole (Cuon alpinus, 95%) from protected areas in the giant panda distribution range since the 1960s. The present findings indicate the insufficiency of giant panda conservation for protecting these large carnivore species and suggest that future conservation efforts should target restoring ecosystems with high trophic complexity to facilitate the recovery of large carnivore populations.


Asunto(s)
Carnívoros , Ursidae , Animales , Ecosistema
10.
Conserv Biol ; 34(1): 158-167, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31069848

RESUMEN

Flagship species have been used widely as umbrella species (i.e., species with large home range whose protection often provides protection for sympatric species) in the management of China's nature reserves. This conflation of flagship and umbrella species is best represented by the giant panda (Ailuropoda melanoleuca) and other large, endangered mammals designated as conservation targets in site selection and planning of reserves. Few empirical studies have tested the effectiveness of flagship species as surrogates for a broader range of sympatric species. Using extensive camera-trap data, we examined the effectiveness of management zones designated to protect flagship (target) species in conserving sympatric species in 4 wildlife reserves (Gutianshan, Changqing, Laohegou, and Wolong). We tested whether the progression from peripheral to core zones was associated with an increasing habitat association for both target and sympatric species. The distribution patterns of the study species across the zones in each reserve indicated a disparity between management zones and the species' habitat requirements. Management zone was included in the final model for all target species, and most of them had higher occurrence in core zones relative to less-protected zones, but zone was not a predictor for most of the sympatric species. When management zone was associated with the occurrence of sympatric species, threatened species generally had higher detections in core zones, whereas common species had higher detections outside of the core zone. Our results suggested that reserve planning based on flagship species does not adequately protect sympatric species due to their specialized habitat requirements. We recommend re-examining the effectiveness of management zoning and urge a multispecies and reserve-wide monitoring plan to improve protection of China's wildlife.


Efectividad del Manejo de Zonación Diseñada para Especies Bandera en la Protección de Especies Simpátricas Resumen Las especies bandera se han utilizado ampliamente como especies paraguas (es decir, especies con una extensa distribución cuya protección frecuentemente proporciona protección para especies simpátricas) en el manejo de las reservas naturales de China. Esta combinación de especie bandera y especie paraguas tiene su mejor representación en el panda gigante (Ailuropoda melanoleuca) y otros grandes mamíferos en peligro de extinción designados como objetivos de conservación en la selección de sitio y la planeación de reservas. Pocos estudios empíricos han probado la efectividad de las especies bandera como sustitutas de una especie simpátrica con una distribución más amplia. Con datos numerosos de cámaras trampa, examinamos la efectividad de las zonas de manejo designadas para proteger a las especies bandera (objetivo) en la conservación de especies simpátricas dentro de cuatro reservas de fauna (Gutianshan, Changqing, Laohegou y Wolong). Probamos si la progresión de las zonas periféricas hacia las zonas núcleo estaba relacionada con asociaciones crecientes de hábitat tanto para las especies objetivo como para las simpátricas. Los patrones de distribución del estudio de especies a lo largo de las zonas en cada reserva indicaron una disparidad entre las zonas de manejo y los requerimientos de hábitat de las especies. La zona de manejo se incluyó dentro del modelo final para todas las especies objetivo y la mayoría de ellas tuvo una presencia más alta en las zonas núcleo en relación con las zonas de menor protección. Cuando la zona de manejo se asoció a la presencia de especies simpátricas, las especies amenazadas generalmente tuvieron un mayor número de detecciones en la zona núcleo, mientras que las especies comunes tuvieron un número más elevado de detecciones fuera de la zona núcleo. Nuestros resultados sugieren que la planeación de reservas basada en las especies bandera no protege adecuadamente a las especies simpátricas debido a sus requerimientos especializados de hábitat. Recomendamos una reexaminación de la efectividad del manejo de zonación y urgimos que se genere un plan de monitoreo multiespecífico en toda la reserva para mejorar la protección de la fauna en China.


Asunto(s)
Conservación de los Recursos Naturales , Simpatría , Animales , China , Ecosistema , Especies en Peligro de Extinción
11.
Nature ; 572(7768): 180-181, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31391563
12.
Sci Adv ; 4(1): eaaq0083, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29387798

RESUMEN

The collision of molecules at ultracold temperatures is of great importance to understand the chemical interactions at the quantum regime. Although much theoretical work has been devoted to this, experimental data are only sparsely available, mainly because of the difficulty in producing ground-state molecules at ultracold temperatures. We report here the creation of optically trapped samples of ground-state bosonic sodium-rubidium molecules with precisely controlled internal states and, enabled by this, a detailed study on the inelastic loss with and without the NaRb + NaRb → Na2 + Rb2 chemical reaction. Contrary to intuitive expectations, we observed very similar loss and heating, regardless of the chemical reactivities. In addition, as evidenced by the reducing loss rate constants with increasing temperatures, we found that these collisions are already outside the Wigner region although the sample temperatures are sub-microkelvin. Our measurement agrees semiquantitatively with models based on long-range interactions but calls for a deeper understanding on the short-range physics for a more complete interpretation.

14.
Sci Rep ; 7(1): 17983, 2017 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-29269860

RESUMEN

The Przewalski's gazelle (Procapra przewalskii) is one of the most endangered ungulates in the world, with fewer than 2,000 individuals surviving in nine habitat fragments on the Qinghai-Tibet Plateau and isolated by human settlements and infrastructure. In particular, the Qinghai-Tibet railway, which crosses the largest part of the gazelle's distribution, remains a major concern because of its potential to intensify landscape genetic differentiation. Here, using mtDNA sequencing and microsatellite genotyping to analyze 275 Przewalski's gazelle samples collected throughout the range, we observed low level of genetic diversity (mtDNA π = 0.0033) and strong phylogeographic structure. Overall, the nine patches of gazelles can be further clustered into five populations, with a strong division between the eastern vs. western side of Qinghai Lake. Our study provides the first evidence of the genetic divergence between the Haergai North and Haergai South gazelle populations, corresponding to the recent construction of a wired enclosure along the Qinghai-Tibet railway less than ten years ago, an equivalent of five generations. Well-designed wildlife corridors across the railway along with long-term monitoring of the anthropogenic effects are therefore recommended to alleviate further habitat fragmentation and loss of genetic diversity in Przewalski's gazelle.


Asunto(s)
Antílopes , Especies en Peligro de Extinción , Vías Férreas , Animales , Antílopes/genética , Conservación de los Recursos Naturales , Especies en Peligro de Extinción/estadística & datos numéricos , Femenino , Variación Genética , Genética de Población , Masculino , Tibet
15.
Rev Sci Instrum ; 88(7): 076105, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28764500

RESUMEN

We present a four-pass acousto-optic modulator (AOM) system for providing the repumping light for laser cooling of sodium atoms. With only one 400 MHz AOM, we achieve a tunable laser frequency shift around 1.6 GHz with total efficiency up to 30%. This setup provides an alternative over conventional methods to generate a sodium repumping light using more expensive high frequency AOMs or electro-optical modulators (EOMs) in the GHz domain. This compact and reliable setup can be easily adapted to other frequencies and may find applications in laser spectroscopy, laser cooling and trapping, and coherent manipulation of atomic quantum states.

16.
Sci Rep ; 7: 41909, 2017 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-28195150

RESUMEN

Dietary information is lacking in most of small to mid-sized carnivores due to their elusive predatory behaviour and versatile feeding habits. The leopard cat (LPC; Prionailurus bengalensis) and the Asiatic golden cat (AGC; Catopuma temminckii) are two important yet increasingly endangered carnivore species in the temperate mountain forest ecosystem in Southwest China, a global biodiversity hotspot and a significant reservoir of China's endemic species. We investigated the vertebrate prey of the two sympatric felids using faecal DNA and a next-generation sequencing (NGS)/metabarcoding approach. Forty vertebrate prey taxa were identified from 93 LPC and 10 AGC faecal samples; 37 taxa were found in the LPC diet, and 20 were detected in the AGC diet. Prey included 27 mammalian taxa, 11 birds, one lizard and one fish, with 73% (29/40) of the taxa assigned to the species level. Rodents and pikas were the most dominant LPC prey categories, whereas rodents, pheasant, fowl and ungulates were the main AGC prey. We also analysed the seasonal and altitudinal variations in the LPC diet. Our results provide the most comprehensive dietary data for these felids and valuable information for their conservation planning.


Asunto(s)
Biodiversidad , Dieta , Especies en Peligro de Extinción , Felidae/fisiología , Altitud , Animales , China , Heces/química , Conducta Predatoria , Estaciones del Año
17.
PLoS One ; 11(10): e0164271, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27723772

RESUMEN

Understanding the interactions between species and their coexistence mechanisms will help explain biodiversity maintenance and enable managers to make sound conservation decisions. Mesocarnivores are abundant and diverse mid-sized carnivores and can have profound impacts on the function, structure and dynamics of ecosystem after the extirpation of apex predators in many ecosystems. The moist temperate forests of Southwest China harbor a diverse community of mesocarnivores in the absence of apex predators. Sympatric species tend to partition limited resources along time, diet and space to facilitate coexistence. We determined the spatial and temporal patterns for five species of mesocarnivores. We used detection histories from a large camera-trap dataset collected from 2004-2015 with an extensive effort of 23,313 camera-days from 495 camera locations. The five mesocarnivore species included masked palm civet Paguma larvata, leopard cat Prionailurus bengalensis, hog badger Arctonyx collaris, yellow-throated marten Martes flavigula, and Siberian weasel Mustela sibirica. Only the masked palm civet and hog badger tended to avoid each other; while for other pairs of species, they occurred independently of each other, or no clear pattern observed. With regard to seasonal activity, yellow-throated marten was most active in winter, opposite the pattern observed for masked palm civet, leopard cat and hog badger. For diel activity, masked palm civet, leopard cat and hog badger were primarily nocturnal and crepuscular; yellow-throated marten was diurnal, and Siberian weasel had no clear pattern for most of the year (March to November), but was nocturnal in the winter (December to February). The seasonal shift of the Siberian weasel may be due to the high diet overlap among species in winter. Our results provided new facts and insights into this unique community of mesocarnivores of southwest China, and will facilitate future studies on the mechanism determining coexistence of animal species within complex system.


Asunto(s)
Carnívoros/fisiología , Bosques , Animales , China , Ecosistema , Estaciones del Año
19.
Phys Rev Lett ; 116(20): 205303, 2016 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-27258875

RESUMEN

We report the successful production of an ultracold sample of absolute ground-state ^{23}Na^{87}Rb molecules. Starting from weakly bound Feshbach molecules formed via magnetoassociation, the lowest rovibrational and hyperfine level of the electronic ground state is populated following a high-efficiency and high-resolution two-photon Raman process. The high-purity absolute ground-state samples have up to 8000 molecules and densities of over 10^{11} cm^{-3}. By measuring the Stark shifts induced by external electric fields, we determined the permanent electric dipole moment of the absolute ground-state ^{23}Na^{87}Rb and demonstrated the capability of inducing an effective dipole moment over 1 D. Bimolecular reaction between ground-state ^{23}Na^{87}Rb molecules is endothermic, but we still observed a rather fast decay of the molecular sample. Our results pave the way toward investigation of ultracold molecular collisions in a fully controlled manner and possibly to quantum gases of ultracold bosonic molecules with strong dipolar interactions.

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