70 research outputs found

    Theory of polygonal phases self-assembled from T-shaped liquid crystalline polymers

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    Extensive experimental studies have shown that numerous ordered phases can be formed via the self-assembly of T-shaped liquid crystalline polymers (TLCPs) composed of a rigid backbone, two flexible end chains and a flexible side chain. However, a comprehensive understanding of the stability and formation mechanisms of these intricately nano-structured phases remains incomplete. Here we fill this gap by carrying out a theoretical study of the phase behaviour of TLCPs. Specifically, we construct phase diagrams of TLCPs by computing the free energy of different ordered phases of the system. Our results reveal that the number of polygonal edges increases as the length of side chain or interaction strength increases, consistent with experimental observations. The theoretical study not only reproduces the experimentally observed phases and phase transition sequences, but also systematically analyzes the stability mechanism of the polygonal phases

    Commodifying Non-English Foreign Language via Chinese University Websites

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    This paper examines the commodification of non-English foreign languages through the official websites of 42 China’s double first-class universities. Informed by the concepts of language as commodity (Heller 2010), this study examines how non-English foreign languages are ideologically constructed as valued resources exchange for decent job, advanced education and China’s regional integration. However, the study also finds that even these websites try their best to portray non-English foreign languages as valuable commodity, the concept of English as the default language still permeates in the whole promoting process. Therefore, there is still some tensions between ideal promoting vision and actual practices. This study can shed lights on the valorization of multilingual education in China and the promotion of non-English foreign languages to the world

    A study on the correlation between hemoglobin concentration and the storage quality of suspended red blood cells prepared from the whole blood of Tibetan male residents

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    BackgroundPrevious studies reported that the blood of Tibetans living at different altitudes may vary slightly. There is evidence that the harsh environmental conditions at high altitudes, such as low pressure and hypoxia, may affect the morphology and hemorheology of red blood cells (RBCs). Hypoxia would increase the levels of hemoglobin ([Hb]) and hematocrit (Hct), potentially increasing blood hyperviscosity and compromising blood collection and transfusions. Therefore, it is critical to investigate the in vitro storage quality of Tibetan RBCs.ObjectivesIn this study, the in vitro quality of suspended RBCs (SRBCs) prepared from whole blood (WB) of Tibetan residents with varying Hb concentrations ([Hb]) was measured during storage, and the relationship between the major factors in RBC storage and [Hb] was studied.Materials and methodsThe WB of Tibetan men was divided into three groups based on [Hb] levels (group A: 120 < Hb ≤ 185 g/L; group B: 185 < Hb ≤ 210 g/L; group C: Hb > 210 g/L). The SRBCs prepared from WB were examined aseptically on days 1, 14, 21, and 35 after storage.Results[Hb] was not correlated with mean corpuscular volume (MCV), adenosine triphosphate (ATP), pH, P50, and hemolysis. There was a moderate or strong negative association between platelets (PLT) and [Hb] from days 1 to 35, and the PLT number of group C was lower than group A during storage. Group C had the highest change rates of electrolytes, glucose, and lactate, and there were moderate or strong positive correlations between lactate and [Hb] (r = 0.3772, p = 0.0045), glucose and [Hb] (r = 0.5845, p < 0.0001), Na+ and [Hb] (r = 0.3966, p = 0.0027), and K+ and [Hb] (r = 0.4885, p = 0.0002). Group B had the highest change rates of 2,3-DPG on day 35, and there was a negative correlation between 2,3-DPG and [Hb] (r = −0.4933, p = 0.0001).ConclusionsThese new data on the [Hb] could have implications for researchers wishing to study the storage quality of Tibetan SRBCs, particularly in the context of erythrocyte metabolism, and we propose finding a new, suitable alternative solution for plateau SRBCs, particularly the blood with [Hb] greater than 185 g/L. Our results could have important implications for researchers wishing to study the potential framework of high-altitude-induced SRBC storage lesions

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    Evaluation of decompressive craniectomy in mice after severe traumatic brain injury

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    Decompressive craniectomy (DC) is of great significance for relieving acute intracranial hypertension and saving lives after traumatic brain injury (TBI). In this study, a severe TBI mouse model was created using controlled cortical impact (CCI), and a surgical model of DC was established. Furthermore, a series of neurological function assessments were performed to better understand the pathophysiological changes after DC. In this study, mice were randomly allocated into three groups, namely, CCI group, CCI+DC group, and Sham group. The mice in the CCI and CCI+DC groups received CCI after opening a bone window, and after brain injury, immediately returned the bone window to simulate skull condition after a TBI. The CCI+DC group underwent DC and contused tissue removal 6 h after CCI. The mice in the CCI group underwent the same anesthesia process; however, no further treatment of the bone window and trauma was performed. The mice in the Sham group underwent anesthesia and the process of opening the skin and bone window, but not in the CCI group. Changes in Modified Neurological Severity Score, rotarod performance, Morris water maze, intracranial pressure (ICP), cerebral blood flow (CBF), brain edema, blood–brain barrier (BBB), inflammatory factors, neuronal apoptosis, and glial cell expression were evaluated. Compared with the CCI group, the CCI+DC group had significantly lower ICP, superior neurological and motor function at 24 h after injury, and less severe BBB damage after injury. Most inflammatory cytokine expressions and the number of apoptotic cells in the brain tissue of mice in the CCI+DC group were lower than in the CCI group at 3 days after injury, with markedly reduced astrocyte and microglia expression. However, the degree of brain edema in the CCI+DC group was greater than in the CCI group, and neurological and motor functions, as well as spatial cognitive and learning ability, were significantly poorer at 14 days after injury

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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