151 research outputs found

    Estudio de la distribución y abundancia de macrofauna suprabentónica del infralitoral somero

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    El estudio de la comunidad del suprabentos, en 2 playas de la costa Gandia (E de España) ha permitido identificar un total de 20 613 ejemplares, pertenecientes a 44 especies y ocho grupos zoológicos diferentes (misidáceos, anfípodos, isópodos, cumáceos, decápodos, cefalópodos, equinodermos y peces teleósteos). El suprabentos de playas de Gandia se ha caracterizado por una densidad media de 22,9 ind. m-2, por la abundancia de mísidos (58,8% de la densidad total) y de anfípodos (36,5% del total de especies de densidad). Cinco especies fueron consideradas como típicas de los conjuntos suprabentónicos: Schistomysis assimilis, Mesopodopsis slabberi, Gastrossacus sanctus, Siphonoecetes sabbatieri y Philocheras monacanthus. Se confirmó la tendencia general de la macrofauna con la disminución de la diversidad de especies desde las playas disipativas a las reflectivas para las comunidades suprabentónicas.An analysis of the suprabenthos has been carried out on 2 beaches in Gandia coast (E of Spain).A total of 20 613 specimens, belonging to 44 species and eight different zoological groups (mysids, amphipods, cumaceans, isopods, decapods, cephalopods, echinoderms, and teleostean fishes) were obtained. The suprabenthos of Gandia beaches were characterized by a mean density of 22.9 ind. m¿2, by the abundance of Mysids (58.8% of the total density) and of Amphipods (36,5% of the total density species). Five population species were considered as typical of suprabenthic assemblages: Schistomysis assimilis, Mesopodopsis slabberi, Gastrossacus sanctus, Siphonoecetes sabbatieri and Philocheras monacanthus. The macrofaunal trend about to that the species diversity decrease from dissipative to reflective beaches is confirmed for the suprabenthic communitiesZhao, W. (2013). Estudio de la distribución y abundancia de macrofauna suprabentónica del infralitoral somero. Universitat Politècnica de València. http://hdl.handle.net/10251/32802Archivo delegad

    High temperature superconductivity of quaternary hydrides XM3Be4H32 (X, M = Ca, Sr, Ba, Y, La, Ac, Th) under moderate pressure

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    The compressed hydrogen-rich compounds have received extensive attention as promising candidates for room temperature superconductivity, however, the high pressure required to stabilize such materials hinders their wide practical application. In order to search for potential superconducting hydrides that are stable at low pressures, we have investigated the crystal structures and properties of quaternary hydrides, XM3Be4H32 (X, M = Ca, Sr, Ba, Y, La, Ac, Th) based on the first-principles calculations. We identified nine dynamically stable compounds at moderate pressure of 20 GPa. Strikingly, their superconducting transition temperatures are much higher than that of liquid nitrogen, especially CaTh3Be4H32 (124 K at 5 GPa), ThLa3Be4H32(134 K at 10 GPa), LaAc3Be4H32 (135 K at 20 GPa) and AcLa3Be4H32 (153 K at 20 GPa) exhibit outstanding superconductivity at mild pressures. Metal atoms acting as pre-compressors donate abundant electrons to hydrogen, weakening the H-H covalent bond and thus facilitating the metallization of the hydrogen sublattice. At the same time, the appropriate combination of metal elements with different ionic radius and electronegativity can effectively tune the electronic structure near the Fermi level and improve the superconductivity. These findings fully reveal the great promise of hosting high-temperature superconductivity of quaternary hydrides at moderate pressures and will further promote related exploration.Comment: 14 pages, 6 figure

    Wave interference network with a wave function for traffic sign recognition

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    In this paper, we successfully combine convolution with a wave function to build an effective and efficient classifier for traffic signs, named the wave interference network (WiNet). In the WiNet, the feature map extracted by the convolutional filters is refined into many entities from an input image. Each entity is represented as a wave. We utilize Euler's formula to unfold the wave function. Based on the wave-like information representation, the model modulates the relationship between the entities and the fixed weights of convolution adaptively. Experiment results on the Chinese Traffic Sign Recognition Database (CTSRD) and the German Traffic Sign Recognition Benchmark (GTSRB) demonstrate that the performance of the presented model is better than some other models, such as ResMLP, ResNet50, PVT and ViT in the following aspects: 1) WiNet obtains the best accuracy rate with 99.80% on the CTSRD and recognizes all images exactly on the GTSRB; 2) WiNet gains better robustness on the dataset with different noises compared with other models; 3) WiNet has a good generalization on different datasets

    Pathological complete response after neoadjuvant immunotherapy combined with chemotherapy in pediatric rectal carcinoma: A case report

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    BackgroundPediatric colorectal carcinoma (PCRC) is a rare non-embryonal tumor with an incidence of 0.1% to 1% of adults. Immune checkpoint inhibitors (ICIs) targeting programmed death-1 (PD-1) have shown significant efficacy in defective mismatch repair/Microsatellite instability-high (dMMR/MSI-H) metastatic CRC (mCRC). Although several studies have reported neoadjuvant immunotherapy (NIT) in MSI-H/dMMR non-mCRC patients, not all patients achieved pathological complete remission (pCR). There are differences between PCRC and adult colorectal carcinoma (CRC), and the role of NIT in PCRC remains to be further defined.Case presentationWe report the case of a 12-year-old child who was admitted to the hospital with abdominal pain and vomiting for more than 3 months. The child’s diagnosis was difficult and complex. He was initially diagnosed with intestinal obstruction, eventually diagnosed with a rare PCRC and identified as locally advanced colorectal cancer (LACRC) with genetic sequencing results showing MSI-H. After a thorough evaluation by clinicians, he received 4 cycles of Camrelizumab (anti-PD-1 antibody) + CapeOx (capecitabine and oxaliplatin) NIT combination chemotherapy. Repeat imaging and all tumor markers were unremarkable, and R0 resection was achieved. Postoperative pathology showed a tumor regression grade (TRG) of 0 grade determined as pCR. Postoperative review has not shown any recurrence or metastasis to date and the prognosis is good.ConclusionPCRC should improve the diagnostic efficiency to prevent misdiagnosis and miss the best time for treatment. NIT and or chemotherapy can be a reasonable and effective treatment option for dMMR/MSI-H locally advanced PCRC. Our report provides some support and evidence for neoadjuvant immunotherapy for locally advanced PCRC, while highlighting the importance of preoperative detection of microsatellite status for locally advanced PCRC

    A cohort study of factors influencing the physical fitness of preschool children: a decision tree analysis

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    ObjectiveBased on the decision tree model, to explore the key influencing factors of children’s physical fitness, rank the key influencing factors, and explain the complex interaction between the influencing factors.MethodsA cohort study design was adopted. 1,276 children (ages 3–6) from 23 kindergartens in Nanchang, China, were chosen for the study to measure the children’s physical fitness at baseline and a year later and to compare the physical fitness scores at the two stages. The study was conducted following the Chinese National Physical Fitness Testing Standard (Children Part); To identify the primary influencing factors of changes in physical fitness, a decision tree model was developed, and a questionnaire survey on birth information, feeding patterns, SB, PA, dietary nutrition, sleep, parental factors, and other relevant information was conducted.ResultsThe levels of physical fitness indicators among preschool children showed a significant increase after 1 year. The accuracy of the CHAID model is 84.17%. It showed that 7 variables were strongly correlated with the physical changes of children’s fitness, the order of importance of each variable was weekend PA, weekend MVPA, mother’s BMI, mother’s sports frequency, father’s education, mother’s education, and school day PA. Three factors are related to PA. Four factors are related to parental circumstances. In addition to the seven important variables mentioned, variables such as breakfast frequency on school day, puffed food, frequency of outing, school day MVPA, parental feeling of sports, father’s occupation, and weekend breakfast frequency are all statistically significant leaf node variables.ConclusionPA, especially weekend PA, is the most critical factor in children’s physical fitness improvement and the weekend MVPA should be increased to more than 30 min/d based on the improvement of weekend PA. In addition, parental factors and school day PA are also important in making decisions about changes in fitness for children. The mother’s efforts to maintain a healthy BMI and engage in regular physical activity are crucial for enhancing the physical fitness of children. Additionally, other parental factors, such as the parents’ educational levels and the father’s occupation, can indirectly impact the level of physical fitness in children

    Terahertz-driven Luminescence and Colossal Stark Effect in CdSe:CdS Colloidal Quantum Dots

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    Unique optical properties of colloidal semiconductor quantum dots (QDs), arising from quantum mechanical confinement of charge within these structures, present a versatile testbed for the study of how high electric fields affect the electronic structure of nanostructured solids. Earlier studies of quasi-DC electric field modulation of QD properties have been limited by the electrostatic breakdown processes under the high externally applied electric fields, which have restricted the range of modulation of QD properties. In contrast, in the present work we drive CdSe:CdS core:shell QD films with high-field THz-frequency electromagnetic pulses whose duration is only a few picoseconds. Surprisingly, in response to the THz excitation we observe QD luminescence even in the absence of an external charge source. Our experiments show that QD luminescence is associated with a remarkably high and rapid modulation of the QD band-gap, which is changing by more than 0.5 eV (corresponding to 25% of the unperturbed bandgap energy) within the picosecond timeframe of THz field profile. We show that these colossal energy shifts can be consistently explained by the quantum confined Stark effect. Our work demonstrates a route to extreme modulation of material properties without configurational changes in material sets or geometries. Additionally, we expect that this platform can be adapted to a novel compact THz detection scheme where conversion of THz fields (with meV-scale photon energies) to the visible/near-IR band (with eV-scale photon energies) can be achieved at room temperature with high bandwidth and sensitivity.Comment: 8 pages, 4 figures, supplementary informatio

    Hydroxysafflor Yellow A (HSYA) Improves Learning and Memory in Cerebral Ischemia Reperfusion-Injured Rats via Recovering Synaptic Plasticity in the Hippocampus

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    Hydroxysafflor yellow A (HSYA) is the major active chemical component of the safflower plant flower, which is widely used in Chinese medicine for cerebrovascular and cardiovascular disease treatment. Recent studies have demonstrated that HSYA exerts neuroprotective effect on cerebral ischemia, such as neuronal anti-apoptosis, antioxidant activity and oxygen free radical-scavenging. However, whether and how HSYA has a protective effect on cognitive impairment induced by cerebral ischemia reperfusion remains elusive. In the present study, by using the middle cerebral artery occlusion (MCAO) model, we found that 8 mg/kg and 16 mg/kg HSYA administration by common carotid artery (CCA) injection improved impaired cognitive function in Morris water maze (MWM) and passive avoidance tasks, but not 4 mg/kg HSYA treatment, suggesting that HSYA treatment in a certain concentration can improve cognitive impairment in MCAO rats. Furthermore, we found that 8 mg/kg HSYA treatment rescued the impaired long-term potentiation (LTP) in hippocampus of MCAO rats. Taken together, these results for the first time demonstrate that HSYA has the capacity to protect cognitive function and synaptic plasticity against cerebral ischemia-reperfusion injury, and provide a new insight that HSYA may be a promising alternative for recovery of cognitive dysfunction after brain ischemic injury

    Preparation and Membrane Permeability of Curcumin Nanoparticles by Subcritical Water Technology

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    Curcumin (Cur) nanoparticles were prepared by subcritical water (SBCW) method and its membrane permeability was evaluated. The processing conditions for the preparation of curcumin nanoparticles were investigated in terms of its particle size distribution, polydispersity index (PDI) and zeta potential, and the prepared nanoparticles were characterized and evaluated for in vitro membrane permeability. The results showed that nanoparticles with a diameter of 166 nm and a drug loading of 70.2% were obtained under the conditions: SBCW temperature 120 ℃, receiving solvent temperature 0 ℃, subcritical water/receiving solution ratio 1:3 (V/V), 0.04 g/100 mL lactose as stabilizing agent, and 30% (V/V) ethanol as entrainer. Fourier transform infrared (FTIR) spectroscopy showed no structural changes in Cur. Scanning electron microscopy (SEM) showed that Cur nanoparticles were uniformly spherical in shape. Differential scanning calorimetry (DSC) analysis showed a decrease in the crystallinity of the nanoparticles. Cur nanoparticles exhibited excellent membrane permeability in vitro, and the permeation rate in the first two hours was 25 folds higher than that of free Cur. Furthermore, Cur nanoparticles exhibited good transmembrane capacity in rabbits and significantly enhanced the bioavailability of Cur. The preparation of Cur nanoparticles using subcritical water method has the advantages of high drug loading, good membrane permeability, no need for carriers, simple process, and green environmental protection
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