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Conjugated polymer sorting is recognized as an efficient and scalable method for the selective extraction of semiconducting single-walled carbon nanotubes (s-SWCNTs). However, this process typically requires the use of nonpolar and aromatic solvents as the dispersion medium, which are petroleum-based and carry significant production hazards. Moreover, there is still potential for improving the efficiency of batch purification. Here, this study presents fluorene-based conjugated polymer that integrates diamines containing ethylene glycol chains (ODA) as linkers within the main chain, to effectively extract s-SWCNTs in bio-renewable solvents. The introduction of ODA segments enhances the solubility in bio-renewable solvents, facilitating effective wrapping of s-SWCNTs in polar environments. Additionally, the ODA within the main chain enhances affinity to s-SWCNTs, thereby contributing to increased yields and purity. The polymer achieves a high sorting yield of 55% and a purity of 99.6% in dispersion of s-SWCNTs in 2-Methyltetrahydrofuran. Thin-film transistor arrays fabricated with sorted s-SWCNTs solution through slot-die coating exhibit average charge carrier mobilities of 20-23 cm2 V⁻¹ s⁻¹ and high on/off current ratios exceeding 105 together with high spatial uniformity. This study highlights the viability of bio-renewable solvents in the sorting process, paving the way for the eco-friendly approach to the purification of SWCNTs.

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OBJECTIVE: To identify the risk factors associated with symptomatic vasospasm after aneurysmal subarachnoid hemorrhage (SAH). METHODS: The clinical data of 186 cases with SAH verified by radiology and lumbar puncture were reviewed retrospectively. RESULTS: Fifty-five of the 186 patients (29.6%) developed symptomatic vasospasm. The incidence of symptomatic vasospasm was significantly higher in the patients of Fisher grade III than in those of Fisher grade I and Fisher grade II, in the patients in poor clinical status at admission the in those in better clinical status, and in the patients with repeated reoccurrence of SAH then in those without reoccurrence (all P < 0.01). Sex, age, treatment modality, and use of antifibrinolytic drugs (AFD) did not influence the development of symptomatic vasospasm (all P > 0.05). Multivariate analysis showed that Fisher grade III [odds ratio (OR) 2.549, 95% confidence interval (CI) 1.406 - 4.517], poor clinical status at admission (OR 2.342, 95% CI 1.320 - 4.159) and repeated reoccurrence of SAH (OR 2.492, 95% CI 1.394 approximately 4.448) were associated with the increased risk of symptomatic vasospasm. CONCLUSION: Fisher grade III, poor clinical status at admission and repeated reoccurrence of SAH are significant independent risk factors of symptomatic vasospasm. The presence of symptomatic vasospasm can be independently predicted by the amount of subarachnoid hemorrhage, clinical status at admission, and times of SAH.

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OBJECTIVE: To establish a simple, reproducible, and practical mechanical injury model of hippocampal neurons of Sprague-Dawley rats in vitro. METHODS: Hippocampal neurons isolated from 1-2-day old rats were cultured in vitro. Mild, moderate and severe mechanical injuries were delivered to the neurons by syringe needle tearing, respectively. The control neurons were treated identically with the exception of trauma. Cell damage was assessed by measuring the Propidium Iodide (PI) uptaking at different time points (0.5, 1, 6, 12 and 24 hours) after injury. The concentration of neuron specific enolase was also measured at some time points. RESULTS: Pathological examination showed that degeneration, degradation and necrosis occurred in the injured cultured neurons. Compared with the control group, the ratio of PI-positive cells in the injured groups increased significantly after 30 minutes of injury (P<0.05). More severe the damage was, more PI-positive neurons were detected. Compared with the control group, the concentration of neuron specific enolase in the injured culture increased significantly after 1 hour of injury (P<0.05). CONCLUSIONS: The established model of hippocampal neuron injury in vitro can be repeated easily and can simulate the damage mechanism of traumatic brain injury, which can be used in the future research of traumatic brain injury.

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OBJECTIVE: To study the correlation between brain edema, elevated intracranial pressure (ICP) and cell apoptosis in traumatic brain injury (TBI). METHODS: In this study, totally 42 rabbits in 7 groups were studied. Six of the animals were identified as a control group, and the remaining 36 animals were equally divided into 6 TBI groups. TBI models were produced by the modified method of Feeney. After the impact, ICP of each subject was recorded continuously by an ICP monitor until the animal was sacrificed at scheduled time. The apoptotic brain cells were detected by an terminal deoxynucleotide-transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay. Cerebral water content (CWC) was measured with a drying method and calculated according to the Elliott formula. Then, an analysis was conducted to determine the correlation between the count of apoptotic cells and the clinical pathological changes of the brain. RESULTS: Apoptotic cell count began to increase 2 h after the impact, and reached its maximum about 3 days after the impact. The peak value of CWC and ICP appeared 1 day and 3 days after the impact, respectively. Apoptotic cell count had a positive correlation with CWC and ICP. CONCLUSIONS: In TBI, occurrence of brain edema and ICP increase might lead to apoptosis of brain cells. Any therapy which can relieve brain edema and/or decrease ICP would be able to reduce neuron apoptosis, thereby to attenuate the secondary brain damage.

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OBJECTIVE: To investigate the effect of handportable mobiletelephone microwave radiation on rat central nervous system by setting up rat model. METHODS: 80 healthy male SD rats (weighed about 200 g) were divided into 4 groups at random: control, radiation, decranium, decranium + radiation. TUNEL method was adopted used to detect the apoptosis of neurons after irradiation, then immunohistochemistry was used to detect Bcl-2, Bax expression in all brain tissue. RESULTS: TUNEL positive rate, Bax and Bcl-2 positive cell numbers could be found in decranium + radiation group [(26.45 +/- 9.27)%, (23.5 +/- 3.58), (11.1 +/- 2.55) respectively]. There were significant differences among control [(9.59 +/- 2.55)%, 14.2 +/- 2.46, 7.0 +/- 1.14 respectively], decranium group [(9.52 +/- 1.93)%, 15.5 +/- 1.77, 7.4 +/- 1.76], radiation group [(10.04 +/- 3.62)%, 15.9 +/- 2.02, 7.2 +/- 1.07] (P < 0.01). But the difference was not found in the ratio of Bax to Bcl-2. CONCLUSION: Microwave radiation did not affect the intact rat, but did promote the occurrence of neuron apoptosis in cranial defect rat. Bax, Bcl-2 gene participated in regulation of apoptosis. The intact cranium may be an important factor to protect the neurons against handportable mobiletelephone microwave radiation to some extent.

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