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1.
J Phys Chem A ; 127(33): 6881-6891, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37555550

RESUMO

Molecular dynamics simulations are performed to investigate the coalescing processes between a Cu55 cluster with a liquid, FCC, or Ih structure and a Ag55 cluster in liquid, as well as the structural changes of the coalesced clusters during the cooling process. The simulation results show that the initial structure of the Ag and Cu clusters significantly affects the coalescence stages and the structures after coalescence. There are apparent rotations of the Ag cluster with the liquid structure relative to the Cu cluster with the liquid structure when they are approaching. Before the formation of a neck, the Cu cluster with the Ih structure is more stable and less likely to lose its structure compared to the Cu cluster with the FCC structure. During the cooling process, the coalesced clusters will form different packing structures, including Ih and metastable core/shell structures. The Lode-Nadai values reveal the loading states on the atoms when the two clusters collide. The thermodynamic behaviors during the cooling process were investigated to better understand the order degree of the packing structures and the structural transition processes.

2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(5): 773-776, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36325773

RESUMO

Palliative care refers to the prevention and relief of physical and mental suffering through early recognition,active assessment,and management of pain and other painful symptoms to improve quality of life for both the patients with severe diseases and their families.A successful case of palliative care requires not only the establishment of correct concepts but also the team work and the improvement of the medical system.This paper introduced the end-of-life care experience for a patient with advanced lung cancer,showing the gains and deficiencies in the practice of palliative care.


Assuntos
Neoplasias Pulmonares , Assistência Terminal , Humanos , Cuidados Paliativos , Qualidade de Vida , Neoplasias Pulmonares/terapia , Dor , Morte
3.
Phys Chem Chem Phys ; 24(35): 21040-21051, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36000968

RESUMO

Molecular dynamics simulations are performed to investigate impurity effects on the changes of packing structures, atomic level pressure, and thermodynamics for icosahedral Ag clusters having 55 and 147 atoms. The simulation results indicate that, doping Cu atoms in different cluster shells can significantly affect their thermal stability and thermodynamic values. For the small size clusters, the doping in the interior apparently releases the stress, and improves the stability. The thermodynamic values of entropy and free energy can be used to indicate the order degree of the packing structures and structural transition. The shape changes are related to the local stresses at elevated temperatures.

4.
J Healthc Eng ; 2022: 7011836, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126940

RESUMO

OBJECTIVE: To explore the status quo of psychological resilience, mindfulness level, the sleep quality of pregnant women by Prenatal Diagnosis Screening, and the mediating effect of psychological resilience on sleep quality and mindfulness. METHODS: A survey of 298 pregnant women was conducted using the psychological resilience scale, Pittsburgh sleep quality index, and the concise version of the five-factor mindfulness scale. RESULTS: The total score of psychological resilience of pregnant women was (68.96 ± 17.27), mindfulness was (77.25 ± 12.65), the median of total sleep quality was 6, and the detection rate of sleep disorders was 31.9%. The sleep quality of pregnant women was negatively correlated with mindfulness level and psychological resilience (p < 0.01), and mindfulness level was positively associated with psychological resilience (p < 0.01). Bootstrap analysis showed that psychological resilience played an 14.1% mediating role between mindfulness and sleep quality. CONCLUSION: The psychological resilience of pregnant women is low, sleep quality is poor, and mindfulness is mild to moderate. Psychological resilience plays an important role in mediating between mindfulness level and sleep quality that suggests nursing staff should pay attention to and improve the psychological resilience of pregnant women screened by prenatal diagnosis to improve the mindfulness level and sleep quality of pregnant women screened by prenatal diagnosis.


Assuntos
Atenção Plena , Resiliência Psicológica , Feminino , Humanos , Gravidez , Gestantes/psicologia , Diagnóstico Pré-Natal , Sono , Qualidade do Sono
5.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684823

RESUMO

Molecular dynamics simulations are performed to investigate the changes of packing structures, and thermodynamic quantities including internal energy, entropy, and free energy are used to determine temperature regime and transition time of atomic packing structures. The simulation results show different packing structures as the component composition changes, and there are different packing patterns during cooling. For these Cu-Ag alloy clusters containing only a small number of atoms of Cu, they present FCC packing structures in different parts at high temperatures, and then there are transformations to icosahedral structures. With the increase in content of Cu atoms, there is a transition mechanism from molten state to icosahedron. When the content of Cu atoms is appropriate, core-shell structures can be formed at room temperature.

7.
Elife ; 102021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955356

RESUMO

Animals must balance needs to approach threats for risk assessment and to avoid danger. The dorsal periaqueductal gray (dPAG) controls defensive behaviors, but it is unknown how it represents states associated with threat approach and avoidance. We identified a dPAG threatavoidance ensemble in mice that showed higher activity farther from threats such as the open arms of the elevated plus maze and a predator. These cells were also more active during threat avoidance behaviors such as escape and freezing, even though these behaviors have antagonistic motor output. Conversely, the threat approach ensemble was more active during risk assessment behaviors and near threats. Furthermore, unsupervised methods showed that avoidance/approach states were encoded with shared activity patterns across threats. Lastly, the relative number of cells in each ensemble predicted threat avoidance across mice. Thus, dPAG ensembles dynamically encode threat approach and avoidance states, providing a flexible mechanism to balance risk assessment and danger avoidance.


Assuntos
Aprendizagem da Esquiva , Substância Cinzenta Periaquedutal/fisiologia , Animais , Teste de Labirinto em Cruz Elevado , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
J Neurosci ; 41(25): 5399-5420, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-33883203

RESUMO

The brainstem dorsal periaqueductal gray (dPAG) has been widely recognized as being a vital node orchestrating the responses to innate threats. Intriguingly, recent evidence also shows that the dPAG mediates defensive responses to fear conditioned contexts. However, it is unknown whether the dPAG displays independent or shared patterns of activation during exposure to innate and conditioned threats. It is also unclear how dPAG ensembles encode and predict diverse defensive behaviors. To address this question, we used miniaturized microscopes to obtain recordings of the same dPAG ensembles during exposure to a live predator and a fear conditioned context in male mice. dPAG ensembles encoded not only distance to threat, but also relevant features, such as predator speed and angular offset between mouse and threat. Furthermore, dPAG cells accurately encoded numerous defensive behaviors, including freezing, stretch-attend postures, and escape. Encoding of behaviors and of distance to threat occurred independently in dPAG cells. dPAG cells also displayed a shared representation to encode these behaviors and distance to threat across innate and conditioned threats. Last, we also show that escape could be predicted by dPAG activity several seconds in advance. Thus, dPAG activity dynamically tracks key kinematic and behavioral variables during exposure to threats, and exhibits similar patterns of activation during defensive behaviors elicited by innate or conditioned threats. These data indicate that a common pathway may be recruited by the dPAG during exposure to a wide variety of threat modalities.SIGNIFICANCE STATEMENT The dorsal periaqueductal gray (dPAG) is critical to generate defensive behaviors during encounters with threats of multiple modalities. Here we use longitudinal calcium transient recordings of dPAG ensembles in freely moving mice to show that this region uses shared patterns of activity to represent distance to an innate threat (a live predator) and a conditioned threat (a shock grid). We also show that dPAG neural activity can predict diverse defensive behaviors. These data indicate the dPAG uses conserved population-level activity patterns to encode and coordinate defensive behaviors during exposure to both innate and conditioned threats.


Assuntos
Comportamento Animal/fisiologia , Medo/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
Math Biosci Eng ; 17(6): 6390-6400, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-33378860

RESUMO

Strain is of significance in packing transition, but the key structural information for metal nanoclusters is still limited. Atomic simulations using molecular dynamics (MD) were performed to explore the microscopic details of atomic packing transition in four icosahedral (Ih) Cun@Ag55-n clusters without or with different number of Cu core atoms. Analytical tools were used to demonstrate the packing transition including internal energy per atom, shape factor, pair distribution functions, and atomic stress as well as cross-sectional images. The simulation results showed the differences of strain distribution between the surface and interior regions of these clusters at elevated temperature, which affected the transition temperatures of these four clusters. The increasing temperature resulted in strong tensile strain in the surfaces and Cu/Ag interfaces, which decreased the packing transition from Ih configuration as well as the shape changes.

10.
Nanoscale Res Lett ; 12(1): 219, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28340524

RESUMO

The hydrothermal synthesis of nanocrystalline ZnGa2O4:Cr3+ (ZGC) red phosphor monospheres was accomplished in this work, and the effects of system pH, reactant content, reaction time, and citrate anions (Cit3-) on the phase and morphology evolution of the product were systematically studied. Under the optimized conditions of Cit3-/M = 1.0 molar ratio (M = total cations), pH = 5.0, and 0.2 mmol of Zn2+, well-dispersed ZGC monospheres with an average diameter of ~454 ± 56 nm (average crystallite size ~15 nm) were successfully obtained via hydrothermal reaction at 180 °C for 18 h. Cit3+ ions were demonstrated to be crucial to the formation of monospheres and substantially affect the pathway of phase formation. The ZGC monospheres calcined at 800 °C (average diameter ~353 ± 59 nm; average crystallite size ~30 nm) have an intensity ~6 times that of the original phosphor for the 700 nm red emission of Cr3+ (the 2E → 4A2 transition) under excitation with the O2- → Ga3+ charge transfer band at 250 nm. Fluorescence decay analysis found that the 700 nm emission has lifetime values of ~5 ms for the ZGC phosphors.

11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(6): 1284-8, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18088485

RESUMO

This study was aimed to investigate the effects of DMSO on platelets during pre-treatment for lyophilization, including centrifugation, washing and loading trehalose. After pre-treatment for lyophilization, the expression of platelet membrane surface glycoprotein (GP) including CD62p and PAC-1 was analyzed by FCM before and after induction with thrombin, the mean platelet volume (MPV) and platelet maximal aggregation with several platelet inducers were investigated. The results showed that the expression rates of CD62p and PAC-1, as the platelet activation signs, increased and were 30.37% and 15.01% respectively in group without DMSO after pre-treatment. And their differences in comparison with control were statistically significant, but that of CD62p was 10.72% and PAC was 10.11% in group with DMSO, in comparison with group without DMSO respectively, their differences were statistically significant after diluting with DMSO, CD62p was re-expressed to 54.39% in group with DMSO and more than that in group without DMSO and lower than control statistically significant. PAC-1 was re-expressed to 49.28% in group with DMSO and more than that in group without DMSO (p<0.01) and reached to control. Platelet maximal aggregations induced by thrombin, restocetin and propyl gallate were 92.76%, 91.24% and 89.66 respectively in group with DMSO. These were closed to that in control group and in group without DMSO. But the aggregation induced by ADP was 34.33%, it was less than control (p<0.01) and more than that in group without DMSO (p<0.01). It is concluded that DMSO can inhibit the expression of CD62p and PAC-1 on platelet in vitro. But when diluted with plasma, platelets can express CD62p and PAC-1 induced by thrombin and be led to aggregate by several inducers, so the inhibitory effects of DMSO on platelet activation are reversible. DMSO play roles in inhibitor damage from platelet activation and cryoprotectant. This property of DMSO is very important in research of platelets lyophilization.


Assuntos
Plaquetas , Preservação de Sangue/métodos , Criopreservação , Dimetil Sulfóxido/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Sobrevivência Celular , Criopreservação/métodos , Crioprotetores/farmacologia , Liofilização , Humanos , Ativação Plaquetária/fisiologia , Trealose/sangue , Trealose/farmacologia
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 15(4): 878-81, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17708824

RESUMO

This study was aimed to compare the difference of quality between buffy-coat-collected platelet concentrates (BC-PC) and single-donor plateletpheresis (SDP). 15 packs of BC-PC and 15 units SDP were stored at 20 degrees C - 24 degrees C with agitation. Platelet concentration, platelet volume, residual leukocyte and residual erythrocyte in two groups were examined after preparation for 1 hour. Mean platelet volume, pH value, hypotonic shock response (HSR), CD62p expression and CD62p re-expression of platelet were detected on 0, 1, 2, 3, 4, 5 days of platelet preservation. The results showed that the platelet yields, residual leukocyte and residual erythrocyte in two groups accorded with the national quality standard respectively, but residual leukocyte and residual erythrocyte in BC-PC group were higher than those in SDP group when platelet yields in two groups were equal (p < 0.01). Lactate concentration, CD62p expression of platelet increased with prolongation of preseved time, while pH value decreased gradually. Compared with SDP group, there were significant differences in CD62p expression, CD62p re-expression of platelet preserved for 0 - 5 days (p < 0.01), and in pH value of platelet preserved 2 - 5 days (p < 0.01). There was no changes in HSR of SDP group for 0 - 5 days, while HSR in BC-PC group decreased gradually. There were significant differences in HSR of platelet preserved for 1 - 5 days (p < 0.01). It is concluded that the platelet concentrates prepared by BC-PC are not equal to SDP in quality, the preparation technology of BC-PC should be optimized further in order to reduce residual leukocyte, residual erythrocyte and activated platelet yields, as well as improve the quality of BC-PC.


Assuntos
Plaquetas , Preservação de Sangue , Separação Celular/métodos , Plaquetoferese/métodos , Plaquetas/metabolismo , Plaquetas/fisiologia , Eritrócitos/citologia , Humanos , Ácido Láctico/sangue , Leucócitos/citologia , Selectina-P/sangue , Contagem de Plaquetas , Plaquetoferese/instrumentação , Controle de Qualidade
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