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Animal play encompasses a variety of aspects, with kinematic and social aspects being particularly prevalent in mammalian play behaviour. While the developmental effects of play have been increasingly documented in recent decades, understanding the specific contributions of different play aspects remains crucial to understand the function and evolutionary benefit of animal play. In our study, developing male rats were exposed to rough-and-tumble play selectively reduced in either the kinematic or the social aspect. We then assessed the developmental effects of reduced play on their appraisal of standardized human-rat play ('tickling') by examining their emission of 50 kHz ultrasonic vocalizations (USVs). Using a deep learning framework, we efficiently classified five subtypes of these USVs across six behavioural states. Our results revealed that rats lacking the kinematic aspect in play emitted fewer USVs during tactile contacts by human and generally produced fewer USVs of positive valence compared with control rats. Rats lacking the social aspect did not differ from the control and the kinematically reduced group. These results indicate aspects of play have different developmental effects, underscoring the need for researchers to further disentangle how each aspect affects animals.
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Juego e Implementos de Juego , Vocalización Animal , Animales , Masculino , Ratas/fisiología , Conducta Social , Humanos , Conducta Animal , Fenómenos BiomecánicosRESUMEN
BACKGROUND: Play is a common and developmentally important behaviour in young mammals. Specifically in Norway rats (Rattus norvegicus), reduced opportunity to engage in rough-and-tumble (RT) play has been associated with impaired development in social competence. However, RT play is a complex behaviour having both a kinematic aspect (i.e., performing complex 3D manoeuvres during play fights) and a social aspect (interacting with a playful partner). There has been little research so far on disentangling the two aspects in RT play, especially on how these two aspects affect the affective appraisal of the intense physical contact during play. RESULTS: To examine the developmental effects of kinematic and social play reduction on affective appraisal in rats, we subjected male Long-Evans rats from 21 days old to RT play experience that was reduced either kinematically (through playing in a low ceiling environment) or socially (through playing with a less playful Fischer-344 rat). Starting at 35 days, we measured their production of positively (50-kHz) and negatively (22-kHz) valenced ultrasonic vocalisations (USVs) in a 2-min standardised human-rat play procedure that mimicked the playful sequences of nape contact, pinning, and belly stimulation ('tickling') for ten days. We hypothesised that the rats with kinematically or socially reduced play would perceive the 'tickling' less positively and thus emit positive ultrasonic vocalisations at lower rates compared to control rats with non-reduced play experience. Our results confirmed that each of the treatments reduced play differently: while the kinematic reduction abolished playful pinnings entirely, the social reduction decreased the pinnings and made play highly asymmetric. During the tickling procedure, rats mostly produced 50 kHz USV, indicating that they appraised the procedure as positive. There was a wide inter individual variance and high individual consistency in rats' USV responses to 'tickling'. Crucially, neither the kinematically nor the socially reduced play experience affected either type of USV production when rats were 'tickled'. CONCLUSIONS: This finding indicates that the ability to appraise play-like interactions as positive remains unaffected even when the kinematic or the social aspect of play experience was substantially curtailed.
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This manuscript describes the synthesis of green long afterglow nanophosphors SrAl2O4:Eu2+, Nd3+ using the combustion process. The study encompassed the photoluminescence behavior, elemental composition, chemical valence, morphology, and phase purity of SrAl2O4:Eu2+, Nd3+ nanoparticles. The results demonstrate that after introducing Eu2+ into the matrix lattice, it exhibits an emission band centered at 508 nm when excited by 365 nm ultraviolet light, which is induced by the 4f65d1â4f7 transition of Eu2+ ions. The optimal doping concentrations of Eu2+ and Nd3+ were determined to be 2% and 1%, respectively. Based on X-ray diffraction (XRD) analysis, we have found that the physical phase was not altered by the doping of Eu2+ and Nd3+. Then, we analyzed and compared the quantum yield, fluorescence lifetime, and afterglow decay time of the samples; the co-doped ion Nd3+ itself does not emit light, but it can serve as an electron trap center to collect a portion of the electrons produced by the excitation of Eu2+, which gradually returns to the ground state after the excitation stops, generating an afterglow luminescence of about 15 s. The quantum yields of SrAl2O4:Eu2+ and SrAl2O4:Eu2+, Nd3+ phosphors were 41.59% and 10.10% and the fluorescence lifetimes were 404 ns and 76 ns, respectively. In addition, the Eg value of 4.98 eV was determined based on the diffuse reflectance spectra of the material, which closely matches the calculated bandgap value of SrAl2O4. The material can be combined with polyacrylic acid to create optical anti-counterfeiting ink, and the butterfly and ladybug patterns were effectively printed through screen printing; this demonstrates the potential use of phosphor in the realm of anti-counterfeiting printing.
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Herein, a series of novel long afterglow nanophosphors BaYAl3O7:Eu2+, Nd3+ was synthesized by the combustion method. The investigation encompassed the characterization of X-ray diffraction, morphology, chemical valence, elemental composition, and photoluminescence behavior of BaYAl3O7:Eu2+ and BaYAl3O7:Eu2+, Nd3+ nanoparticles. Under 365 nm excitation, BaYAl3O7:Eu2+ and BaYAl3O7:Eu2+, Nd3+ show emission bands centered at 497 nm and 492 nm, which are attributed to the 4f65dâ4f7 transition of Eu2+ ions. The optimal samples of BaYAl3O7:0.03Eu2+ and BaYAl3O7:0.03Eu2+, 0.02Nd3+ have average fluorescence lifetimes of 850 ns and 1149 ns, respectively. The co-doping of Nd3+ ions as the trap centers produced long afterglow luminescence properties, and the afterglow time could reach up to 8 min. Furthermore, the fluorescent powder can be mixed with polyacrylic acid to prepare anti-counterfeiting inks; a clover pattern and snowflake pattern have been successfully printed using screen printing technology, proving its potential application in the field of anti-counterfeiting.
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A series of long-afterglow luminescent materials (SrAl2O4: Eu2+ (SAOE), SrAl2O4: Eu2+, Dy3+ (SAOED) and SrAl2O4: Eu2+, Dy3+, Gd3+ (SAOEDG)) was synthesized via the combustion method. Temperature and concentration control experiments were conducted on these materials to determine the optimal reaction temperature and ion doping concentration for each sample. The crystal structure and luminescent properties were analyzed via X-ray diffraction (XRD), photoluminescence (PL), and afterglow attenuation curves. The outcomes demonstrate that the kind of crystal structure and the location of the emission peak were unaffected by the addition of ions. The addition of Eu2+ to the matrix's lattice caused a broad green emission with a central wavelength of 508 nm, which was attributed to the characteristic 4f65d1 to 4f7 electronic dipole, which allowed the transition of Eu2+ ions. While acting as sensitizers, Dy3+ and Gd3+ could produce holes to create a trap energy level, which served as an electron trap center to catch some of the electrons produced by the excitation of Eu2+ but did not itself emit light. After excitation ceased, this allowed them to gently transition to the ground state to produce long-afterglow luminescence. It was observed that with the addition of sensitizer ions, the luminous intensity of the sample increased, and the afterglow duration lengthened. The elemental structure and valence states of the doped ions were determined with an X-ray photoelectron spectrometer (XPS). Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the samples. The results show that the sample was synthesized successfully, and the type and content of ions in the fluorescent powder could be determined. The fluorescence lifetime, quantum yield, bandgap value, afterglow decay time, and coordinate position in the coherent infrared energy (CIE) diagram of the three best sample groups were then analyzed and compared. Combining the prepared phosphor with ink provides a new idea and method for the field of anti-counterfeiting through screen printing.
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Song learning is a prime example for cultural transmission of a mating signal. Local or individual song variants are socially learned early in life and adults sing and prefer these songs. An unresolved issue in this context is the question of how learned preferences for specific variants generalise to songs sufficiently similar to the original model. Here we asked whether female zebra finches would generalise early learned song preferences along a similarity gradient based on syllable sharing between test and tutor songs. For each female, this gradient consisted of their tutor's (father's) song (F), two variants of unfamiliar songs edited to share 2/3 (F2/3) and 1/3 (F1/3) of syllables with father's song and an unfamiliar song (UF) not sharing any syllables with the father's song. Females' preferences were measured in a 4-way operant choice arena where birds could perch on different operant perches to trigger playbacks of the four different songs. Number and duration of perch visits were positively associated with the number of syllables that the assigned stimuli shared with fathers' songs. These results suggest that female zebra finches generalise early learned song preferences to songs sharing syllables (and/or voice characteristics) with songs learned early in life.
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Pinzones , Vocalización Animal , Animales , Femenino , Generalización Psicológica , Aprendizaje , ReproducciónRESUMEN
Chronic traffic noise is increasingly recognised as a potential hazard to wildlife. Several songbird species have been shown to breed poorly in traffic noise exposed habitats. However, identifying whether noise is causal in this requires experimental approaches. We tested whether experimental exposure to chronic traffic noise affected parental behaviour and reproductive success in zebra finches (Taeniopygia guttata). In a counterbalanced repeated-measures design, breeding pairs were exposed to continuous playback of one of two types of highway noise previously shown to be either neutral (control) or aversive. Parental nest attendance positively correlated with feeding effort and was higher for the aversive than the control sound and this effect was more pronounced for parents attending larger broods. However, neither noise condition affected offspring number, growth or body mass. The absence of an effect held when we combined our data with data from two other comparable studies into a meta-analysis. We discuss whether the increased nest attendance could be a compensatory strategy that alleviated detrimental noise effects on the chicks, and whether it could be caused by impaired parent-offspring or within-pair communication. Future work should test these hypotheses and investigate potential long-term costs of increased parental engagement.
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Pinzones , Ruido del Transporte , Animales , ReproducciónRESUMEN
Nanocellulose has gained much attention because of its excellent properties. Cationic cellulose nanocrystals (cCNC) shows good adsorptivity toward negative ions and molecules. Phosphate binders are most used to treat hyperphosphatemia and it is significant to develop its alternatives with high specific and low cost in the clinic. Herein, we prepared cCNC and characterized it by FTIR, TEM, dynamic light scattering, and viscosity method. We simulated the binding process of cationic cellulose for phosphate and used it as phosphate binder for hyperphosphatemia therapy to study the phosphate binding effect and evaluate the oral toxicity. Cationic cellulose improved the conditions of mice models and efficiently decreased the level of phosphate in the serum. cCNC had a better binding effect than cationic microcrystalline cellulose both in vitro and in vivo. cCNC could be used as alternatives to phosphate binder for therapy of chronic renal failure and hyperphosphatemia.
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Celulosa/farmacología , Quelantes/farmacología , Hiperfosfatemia/tratamiento farmacológico , Riñón/efectos de los fármacos , Nanopartículas/química , Fosfatos/aislamiento & purificación , Adenina/administración & dosificación , Adsorción , Animales , Biomarcadores/sangre , Celulosa/química , Celulosa/metabolismo , Quelantes/metabolismo , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Modelos Animales de Enfermedad , Heces/química , Humanos , Hiperfosfatemia/inducido químicamente , Hiperfosfatemia/metabolismo , Hiperfosfatemia/patología , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Nanopartículas/administración & dosificación , Fosfatos/metabolismo , Resultado del Tratamiento , Triglicéridos/sangreRESUMEN
Rare Earth Upconversion nanoparticles (UCNPs) are a type of material that emits high-energy photons by absorbing two or more low-energy photons caused by the anti-stokes process. It can emit ultraviolet (UV) visible light or near-infrared (NIR) luminescence upon NIR light excitation. Due to its excellent physical and chemical properties, including exceptional optical stability, narrow emission band, enormous Anti-Stokes spectral shift, high light penetration in biological tissues, long luminescent lifetime, and a high signal-to-noise ratio, it shows a prodigious application potential for bio-imaging and photodynamic therapy. This paper will briefly introduce the physical mechanism of upconversion luminescence (UCL) and focus on their research progress and achievements in bio-imaging, bio-detection, and photodynamic therapy.
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Flexible transparent conductive electrodes (TCEs) are widely applied in flexible electronic devices. Among these electrodes, silver (Ag) nanowires (NWs) have gained considerable interests due to their excellent electrical and optical performances. Ag NWs with a one-dimensional nanostructure have unique characteristics from those of bulk Ag. In past 10 years, researchers have proposed various synthesis methods of Ag NWs, such as ultraviolet irradiation, template method, polyol method, etc. These methods are discussed and summarized in this review, and we conclude that the advantages of the polyol method are the most obvious. This review also provides a more comprehensive description of the polyol method for the synthesis of Ag NWs, and the synthetic factors including AgNO3 concentration, addition of other metal salts and polyvinyl pyrrolidone are thoroughly elaborated. Furthermore, several problems in the fabrication of Ag NWs-based TCEs and related devices are reviewed. The prospects for applications of Ag NWs-based TCE in solar cells, electroluminescence, electrochromic devices, flexible energy storage equipment, thin-film heaters and stretchable devices are discussed and summarized in detail.