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An improved method was developed for the detection of 16 polycyclic aromatic hydrocarbons (PAHs) in mainstream cigarette smoke during combustion. The methodological approach involved matrix matching standard solution preparation, direct injection of the extraction solution, and measurement of standard linearity curves to quantitatively analyze the release of target compounds. Considering the diverse physical and chemical properties as well as distribution patterns of the 16 PAHs in cigarette smoke, the impact of room temperature and high-temperature ion sources on the response of target compounds was investigated. Additionally, the preparation methods of matrix solvents and the matrix effects on the quantitative results of target compounds were also explored. Furthermore, a systematic study was conducted on the smoke release distribution of commercially available cigarettes with different circumferences. The results demonstrated that direct injection of sample extract eliminates the need for sample purification, concentration, and other processing steps employed in current detection methods. This simplifies sample pretreatment procedures while reducing organic solvent usage and consumables consumption. Moreover, it resolves issues related to low operational efficiency when dealing with large quantities of samples. The use of matrix solvent to prepare standard solution effectively reduces the influence of matrix effect, and solves the technical problem of low recovery of target substance in flue gas caused by no purification treatment when using gas chromatography-tandem mass spectrometry (GC-MS/MS) to analyze 16 kinds of PAHs. Under the normal working parameters of the instrument, the electron impact ion source (EI) was used under high temperature to improve the ionization efficiency of the targets in complex matrix and to ensure the accurate analysis of targets with low concentrations. The correlation coefficients (R2) of the calibration curves for 16 PAHs are 0.996 4-0.999 8, the limits of dectection and the limits of quantification are 0.29-1.48, 0.95-4.94 ng/cigarette, respectively. Under different concentration levels, the average recovery is 87.71%-123.26%, and the precision is within 1.58%-9.45%. By analyzing the reference cigarette 3R4F, there is no significant difference between this method and those reported in the literature. The total amount of PAHs released from 58 brands of cigarette samples are 742.76-1 505.99 ng/cigarette. At the same time, with the decrease of tar content in cigarette, the release of PAHs will be reduced accordingly. This method is simple, practical, stable, and accurate, providing more technical means for the detection of trace PAHs in cigarette smoke.

This study aimed to explore the effects of a lexical approach to Chinese English major students' reading comprehension ability as well as students' opinions of this approach. A quasiexperimental study was carried out in a Normal University in southern China for 11 weeks. An intact class of 45 first-year English major students at intermediate level participated in the study. They were instructed using a lexical approach to study four long reading texts. The instruments included reading comprehension tests, a questionnaire, and a semistructured interview. The results showed that students made much progress in reading comprehension after the treatment and they had positive opinions of the lexical approach. It can be concluded from this that the lexical approach had positive impacts on Chinese English major students' reading comprehension ability and it suggests that this approach could be implemented in English language teaching and learning for English majors in higher education.

Whole-brain dynamic functional connectivity is a growing area in neuroimaging research, encompassing data-driven methods for investigating how large-scale brain networks dynamically reorganize during resting states. However, this approach has been rarely applied to functional magnetic resonance imaging (fMRI) data acquired during task performance. In this study, we first combined the psychophysiological interactions (PPI) and sliding-window methods to analyze dynamic effective connectivity of fMRI data obtained from subjects performing the N-back task within the Human Connectome Project dataset. We then proposed a hypothetical model called Condition Activated Specific Trajectory (CAST) to represent a series of spatiotemporal synchronous changes in significantly activated connections across time windows, which we refer to as a trajectory. Our finding demonstrate that the CAST model outperforms other models in terms of intra-group consistency of individual spatial pattern of PPI connectivity, overall representational ability of temporal variability and hierarchy for individual task performance and cognitive traits. This dynamic view afforded by the CAST model reflects the intrinsic nature of coherent brain activities.

Abstract Background Although GqPCR activation often leads to cell survival by activating the PI3K/AKT pathway, it was previously shown that in several cell types AKT activity is reduced and leads to JNK activation and apoptosis. The mechanism of AKT inactivation in these cells involves an IGBP1-coupled PP2Ac switch that induces the dephosphorylation and inactivation of both PI3K and AKT. However, the machinery involved in the initiation of PP2A switch is not known. Methods We used phospho-mass spectrometry to identify the phosphorylation site of PP2Ac, and raised specific antibodies to follow the regulation of this phosphorylation. Other phosphorylations were monitored by commercial antibodies. In addition, we used coimmunoprecipitation and proximity ligation assays to follow protein–protein interactions. Apoptosis was detected by a TUNEL assay as well as PARP1 cleavage using SDS-PAGE and Western blotting. Results We identified Ser24 as a phosphorylation site in PP2Ac. The phosphorylation is mediated mainly by classical PKCs (PKCα and PKCβ) but not by novel PKCs (PKCδ and PKCε). By replacing the phosphorylated residue with either unphosphorylatable or phosphomimetic residues (S24A and S24E), we found that this phosphorylation event is necessary and sufficient to mediate the PP2A switch, which ultimately induces AKT inactivation, and a robust JNK-dependent apoptosis. Conclusion Our results show that the PP2A switch is induced by PKC-mediated phosphorylation of Ser24-PP2Ac and that this phosphorylation leads to apoptosis upon GqPCR induction of various cells. We propose that this mechanism may provide an unexpected way to treat some cancer types or problems in the endocrine machinery.

Abstract The Thermomyces lanuginosus lipase (TLLs) was successfully immobilized within a novel hydrogel matrix through a two-step crosslinking method. TLLs were initially crosslinked through the Schiff base reaction by oxidized carboxymethyl cellulose (OCMC). The water-soluble OCMC@TLLs complex was subsequently crosslinked by carboxymethyl chitosan (CMCSH) in a microfluidic apparatus to form the CMCHS/OCMC@TLLs microspheres. The CD (Circular Dichroism, CD) and FT-IR (Fourier Transform infrared spectroscopy, FT-IR) spectra demonstrated that the crosslinking of TLLs with OCMC resulted in a less significant impact on their structure compared to that with glutaraldehyde. CMCHS/OCMC@TLLs showed decreased catalytic performance due to the mass transfer resistance, while its thermal stability was greatly improved. The CMCHS/OCMC@TLLs were used to catalyze the lauroylation of arbutin in tetrahydrofuran. After 12 h of reaction under optimal conditions, the yield of 6′-O-lauryl arbutin reached an impressive 92.12%. The prepared 6′-O-lauryl arbutin has high lipophilicity and exhibits similar tyrosinase inhibitory activity and higher antioxidant activity compared to its parent compound. Graphical Abstract

Objective To investigate the “Precision Treatment for Oncology” course, which is offered by Peking Union Medical College.The course is aiming for collecting students′ opinions and suggestions to optimize the course setting and improve the teaching quality. Methods This investigation collected data by questionnaire survey and interviewing from Dec.2021 to Feb.2022. The questionnaire data and interview data were analysed. Results Thirty-six quantitative questionnaires and five qualitative questionnaires were included. Improving professional knowledge and personal interests were two main reasons for students to choose courses, which existed statistical differences on different aspects of course evaluation. The overall score evaluated by medical students was 9.22 and 94.4% of the students thought the course achieved the desired goal. The scores of teachers′ teaching attitude, frontier and practicality of course content were 9.81, 9.08 and 8.86 points respectively. The students hoped to increase the case analysis practice and thematic discussion activities to enrich the teaching form. Conclusions This elective course for graduate is recognized and accepted by students. More efforts are needed in future to optimize curriculum settings, innovate teaching methods, improve teaching quality and explore new pathways for medical graduate education matching the needs of students.

Abstract Background The present study aimed to investigate the differences in chronobiology and prevention between patients with acute type-A aortic dissection (ATAAD) complicated with sleep apnea syndrome (SAS) and without sleep apnea syndrome (non-SAS). Methods We retrospectively analyzed the clinical information of ATAAD patients using hospital medical records and regional meteorological and chronological information between January 2013 and December 2019. Results An early mortality rate of 16.9% (196 out of 1160 cases) was observed, comprising 95 cases of aortic rupture before surgery and 101 surgery-related deaths. Eighty-one of the 964 survivors were screened for SAS using complete morphological characteristics. Of these patients, 291 (33.0%) suffered from SAS, while 590 (67.0%) had no SAS. Based on a Circular Von Mises distribution analysis, the non-SAS patients experienced a significant morning peak in the occurrence of ATAAD at 10:04 (r1 = 0.148, p 0.05). Furthermore, SAS patients experienced a peak on Fridays (χ2 = 36.419, p

Abstract Ulva is one of the main green algae causing green tide disasters. Ulvan is the primarily component polysaccharide of the cell wall of Ulva and its complex structure and monosaccharide composition resulted in various biological activities. However, the high-value and effective utilization of extracted ulvan have been obstructed by limitations ranging from large molecular weight and low solubility to poor bioavailability. Ulva oligosaccharide obtained by degrading ulvan can not only ideally retain the various biological activities of ulvan very well but also effectively solve the problems of low solubility and poor bioavailability. The preparation and biological activity studies of ulvan and Ulva oligosaccharides have become a hot spot in the field of marine biological resources development research. At present, the comprehensive reviews of ulvan and Ulva oligosaccharides are still scarce. What are overviewed in this paper are the chemical composition, structure, extraction, and purification of ulvan and Ulva oligosaccharides, where research progress on the biological activities of ulvan and Ulva oligosaccharides is summarized and prospected. A theoretical and practical basis has been provided for further research on ulvan and Ulva oligosaccharides, as well as the high-value development and effective utilization of marine algae resources. Graphical Abstract

High-temperature vapour-phase acetylation (HTVPA) is a simultaneous acetylation and heat treatment process for wood modification. This study was the first investigation into the impact of HTVPA treatment on the resistance of wood to biological degradation. In the termite resistance test, untreated wood exhibited a mass loss (MLt) of 20.3%, while HTVPA-modified wood showed a reduced MLt of 6.6–3.2%, which decreased with an increase in weight percent gain (WPG), and the termite mortality reached 95–100%. Furthermore, after a 12-week decay resistance test against brown-rot fungi (Laetiporus sulfureus and Fomitopsis pinicola), untreated wood exhibited mass loss (MLd) values of 39.6% and 54.5%, respectively, while HTVPA-modified wood exhibited MLd values of 0.2–0.9% and −0.2–0.3%, respectively, with no significant influence from WPG. Similar results were observed in decay resistance tests against white-rot fungi (Lenzites betulina and Trametes versicolor). The results of this study demonstrated that HTVPA treatment not only effectively enhanced the decay resistance of wood but also offered superior enhancement relative to separate heat treatment or acetylation processes. In addition, all the HTVPA-modified wood specimens prepared in this study met the requirements of the CNS 6717 wood preservative standard, with an MLd of less than 3% for decay-resistant materials.

Summary: Ferroptosis is a form of regulated cell death with roles in degenerative diseases and cancer. Excessive iron-catalyzed peroxidation of membrane phospholipids, especially those containing the polyunsaturated fatty acid arachidonic acid (AA), is central in driving ferroptosis. Here, we reveal that an understudied Golgi-resident scaffold protein, MMD, promotes susceptibility to ferroptosis in ovarian and renal carcinoma cells in an ACSL4- and MBOAT7-dependent manner. Mechanistically, MMD physically interacts with both ACSL4 and MBOAT7, two enzymes that catalyze sequential steps to incorporate AA in phosphatidylinositol (PI) lipids. Thus, MMD increases the flux of AA into PI, resulting in heightened cellular levels of AA-PI and other AA-containing phospholipid species. This molecular mechanism points to a pro-ferroptotic role for MBOAT7 and AA-PI, with potential therapeutic implications, and reveals that MMD is an important regulator of cellular lipid metabolism.

Abstract Background Aortic arch pathologies are concerning clinical conditions with poor prognoses. The use of thoracic endovascular aortic repair (TEVAR) has been investigated to treat aortic arch pathologies. Nonetheless, cerebral blood flow regulation during endovascular aortic arch repair therapy remains challenging. Castor, a unique single-branched stent graft, has been proven effective for retaining the left subclavian artery (LSA). This study aimed to determine whether endovascular therapy for pathologies involving the aortic arch using Castor in combination with the in-vitro fenestration technique is promising, effective, and safe. Methods Eligible patients were enrolled between June 2018 and December 2021. All patients underwent TEVAR with an evaluated proximal landing zone for “Castor” located in Ishimaru zones 0–1. Moreover, the supra-aortic branches (SABs) were reconstructed using the Castor in combination with the in-vitro fenestration technique. Results Herein, 57 patients with aortic arch lesions were treated with Castor in combination with the in-vitro fenestration technique. Innominate artery and the left carotid artery (LCA) were reconstructed in 5 patients, LCA and left subclavian artery (LSA) were reconstructed in 22 patients, and the total SABs were effectively reconstructed in 30 patients (including a hybrid arch repair case). Among them (excluding a hybrid arch repair case) were in-vitro fenestration methodologies for LCA in 32 of 34 cases (2 switched to in-situ fenestration) and LSA in 51 of 56 cases (3 switched to in-situ fenestration and 2 converted to spring coil caulking); furthermore, LCA and LSA in-vitro fenestration were simultaneously successfully performed in 27 of 34 cases. There were no surgical-related neurological complications, and early mortality was estimated at 5.26%. At a mean follow-up of 3.75 months, computed tomography (CTA) images confirmed that each branch stent remained patent. There were no signs of endoleaks, migrative manifestations, or the need for secondary endovascular intervention or conversion to open surgical procedures. Conclusion Castor, in combination with in-vitro fenestration, reflects a feasible, efficient procedure for re-developing SABs.

Rapid extraction and concentration systems based on green materials such as cellulose or lignin are promising. However, there is still a need to optimize the material properties and production processes. Unlike conventional cellulose or lignin sorbent materials, aquatic reed root cells can concentrate external organic pollutants in the water and accumulate them in the plant. Inspired by this, a new nanocellulose–lignin aerogel (NLAG) was designed, in which nanocellulose was used as a substrate and lignin and polyamide epoxy chloropropane were used to crosslink cellulose in order to enhance the strength of the NLGA, resulting in good mechanical stability and water–oil amphiphilic properties. In practical applications, the organic membrane on the NLAG can transport organic pollutants from water to the NLAG, where they are immobilized. This is evidenced by the fact that the aerogel can remove more than 93% of exogenous phenol within a few minutes, highly enriching it inside. In addition, the aerogel facilitates filtration and shape recovery for reuse. This work establishes a novel biopolymer–aerogel-based extraction system with the advantages of sustainability, high efficiency, stability, and easy detachability, which are hard for the traditional adsorbent materials to attain.

Objective: To investigate the effect of the screw configuration on the polylactic acid flow field on the structural parameters of the screw on the end face of the screw in the meshing counter rotating twin screw extruder. Methods: The theoretical model of the heterodirectional double-ended threaded element was established by Solidworks software and the geometry of the threaded element after adjusting the structural parameters in two different ways. The established three-dimensional model was imported into Gambit software for meshing, and then Polyflow software was applied to the flow field simulation calculation. Finally, the flow field distribution results were extracted by Fieldview software, and the effects of the adjustment of the structural parameters on the end surface of the threaded element during correction were compared and analyzed on the shear rate field, viscosity field and speed field. Results: The structural parameters of the threaded element during correction will affect the polylactic acid flow field after being adjusted in two ways. The two adjustment methods of structural parameters have reduced the shear rate gradient in the runner to varying degrees, and the first method has also caused the viscosity of the polymer lactic acid in the runner to be reduced. Conclusion: From the perspective of the influence on the shear rate field, viscosity field and speed field, the threaded element adjusted by mode one is more conducive to extrusion, while the solid configuration of the threaded element adjusted by mode two is closer to the theoretical configuration of the threaded component.

Objective: This study aimed to select a suitable drying method for preserved yellow peach. Methods: Preserved yellow peach was prepared by hot air drying (HAD), microwave-hot air drying (MHD) and vacuum freeze drying (VFD). Its physical properties, nutritional components, sensory and aroma indexes were studied. Results: Compared with traditional HAD, the efficiency of MHD was increased by 56.1%, and the preserved fruit was significantly better than HAD in color, nutritional composition, sensory evaluation, aroma components and content; The preserved yellow peach fruit by VFD has the best color, the strongest rehydration, the best tissue structure integrity of the product, the highest contents of nutrients vitamin C, and total phenol and titratable acid, and the highest sensory score is 91.58. It has the most aroma components and contents, and uniquely has two aroma components: 2-hexenol and trans-2-hexenal. Conclusion: Compared with HAD, the preserved yellow peach fruit prepared by MHD is better in all aspects, and MHD is more suitable for the production of common preserved yellow peach fruit. The quality of preserved yellow peach fruit prepared by VFD is the best. However, due to the high-energy and -cost consumption, it is recommended to produce high-quality preserved fruit.

Abstract Background Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi can cause important intestinal diseases in ruminants. However, data on the distribution of these three protozoan pathogens in Tibetan sheep are limited. Methods We collected 761 fecal samples from Tibetan sheep across four seasons in Qinghai Province, China, and screened the samples for Cryptosporidium spp., G. duodenalis and E. bieneusi using PCR-based sequence analysis of the genes encoding 18S ribosomal RNA, triosephosphate isomerase and the internal transcribed spacer, respectively. Results The positivity rates of Cryptosporidium spp., G. duodenalis and E. bieneusi in Tibetan sheep were 3.68% (28/761 samples), 1.58% (12/761) and 6.44% (49/761), respectively. Four species of Cryptosporidium were identified: C. xiaoi (n = 13 samples), C. ubiquitum (n = 8), C. bovis (n = 6) and C. ryanae (n = 1). Two G. duodenalis assemblages, namely the A (n = 2 samples) and E (n = 10) assemblages, were detected. Five zoonotic E. bieneusi genotypes were found: BEB6 (n = 21 samples), COS-I (n = 14), CHS3 (n = 11) and CGS1 (n = 2) from group 2, and PIGEBITS5 (n = 1) from group 1. Geographic differences in the distribution of E. bieneusi, and seasonal differences for all the three protozoan pathogens were noted. Conclusions Our results elucidate the prevalence and genetic diversity of these three pathogens in Tibetan sheep across different regions and seasons, including zoonotic pathogens such as C. ubiquitum, C. ryanae, G. duodenalis assemblage A and five genotypes of E. bieneusi. Graphical Abstract

Neutralisation assays are key to understanding immune responses to SARS-CoV-2 infection or vaccination. Here, the authors report a surrogate virus neutralization assay called Neu-SATiN, which measures neutralization directly from sera, and allows easy adaptation to variant-specific testing.

Objective: Explore the effects of different combinations of forward screw elements in the melt conveying section on the melt conveying characteristics of reverse screw elements. Methods: Two different models were constructed by changing the lead, using SolidWorks software to establish a three-dimensional model, and using Polyflow software to numerically simulate the extrusion process of the two models in the melt conveying section. The effects of the screw groove width and screw edge thickness of the screw elements on the flow field under different lead lengths and the changes in the flow field at different rotational speeds were analyzed, and the effects of rotational speed on the material mixing were verified through experiments. Results: The constructed model can allow the melt to pass through the reverse threaded element. At the same screw speed, the pressure building capacity and conveying capacity of model one constructed from large lead screw elements were stronger than that of model two constructed from small lead screw elements. Model one was superior to Model two in terms of decentralized mixing ability, and weaker than Model two in terms of distributed mixing ability. Under the same pressure difference at both ends, increasing the rotational speed could improve the dispersion and mixing effects of materials. Conclusion: Using model one in the improved processing of polylactic acid and increasing the rotational speed of the screw can further crush the material and improve the quality of the extrusion.

Abstract Background The percutaneous device closure of patent ductus arteriosus (PDA) is widely used in clinical practice, however full data on the changes in myocardial injury and systemic inflammatory markers’ levels after PDA in children are not fully reported. Methods We have conducted a retrospective analysis of the medical records of 385 pediatric patients in our hospital from January 2017 to December 2019. The patients were distributed into five groups. The first four (A, B, C and D) included patients divided by the type of the surgical closure methods, namely ligation, clamping, ligation-combined suturing and ligation-combined clamping, respectively. The fifth group E comprised of percutaneous device PDA patients. All recorded medical and trial data from the five groups were statistically studied. Results No serious complications in the patients regardless of the classification group were reported. Our results suggested that there were no considerable differences between the groups at the baseline (with all P > 0.05). Group E demonstrated a significantly smaller operative time (42.39 ± 3.88, min) and length of hospital stay (LOS) (4.49 ± 0.50, day), less intraoperative blood loss (7.12 ± 2.09, ml) while on the other hand, a higher total hospital cost (24,001.35 ± 1152.80, RMB) than the other four groups (with all P 0.05) among the four groups. On the contrary, when the aforementioned factors and markers of all the surgical groups were compared to those in group E, we observed significantly higher speed and magnitude of changes in group E than those in groups A, B, C, and D (with all P