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β-cyclodextrin butenate was synthesized by using N, N’-Carbonyldiimidazole (CDI) activating reagent and 4-Dimethylaminopyridine (DMAP) as catalyst. The best preparation condition of β-CD butenate was described as below: reaction temperature was 25°C, concentration of 2-butenoic acid was 450 mmol/L, concentration of DMAP was 12.5 mmol/L and reaction time was 20 minutes and at this condition the yield of β-CD butenate was 0.83 mmol/g. According to the results of FT-IR spectrum, NMR spectroscopy and HPLC-QTof-mass spectrum of β-CD butenate, there were four types β-CD butenate synthesized, which were β-CD-2-butenoic acid monoester, β-CD-2-butenoic acid diester, β-CD-2-butenoic acid triester and β-CD-2-butenoic acid tetraester, respectively.

Parkinson’s disease (PD) is the second most common neurodegenerative disease with complex pathogenesis. Although HOXA transcript antisense RNA myeloid-specific 1 (HOTAIRM1) is upregulated in PD, its exact role in HOTAIRM1 is seldom reported. The purpose of this study is to research the effect of HOTAIRM1 on 1-methyl-4-phenylpyridonium (MPP+)-induced cytotoxicity and oxidative stress in SH-SY5Y cells.

To explore the effect of different microbial strains on blueberry pomace with solid-state fermentation (SSF), three fungi strains and three lactic acid bacteria (LAB) strains were utilized to investigate with respect to polyphenol profiles, antioxidant capacities, and bioaccessibility. Different strains exhibited different capacities for metabolizing polyphenolic compounds in blueberry pomace. The contents of 10 phenolic acids and 6 flavonoids (except (+)-catechin) were increased in blueberry pomace fermented by Lactobacillus acidophilus (LA). A similar tendency was observed in blueberry pomace fermented by Aspergillus niger (AN) and Lactobacillus plantarum (LP), where the concentration of 8 phenolic acids and 5 flavonoids was enhanced, with the following exceptions: (+)-catechin, ferulic acid, vanillic acid, and quercitrin. Chlorogenic acid and quercetin were the maximum phenolic acids and flavonoids in blueberry pomace with SSF, upgraded at 22.96 and 20.16%, respectively. Contrary to the growth of phenolic acids and flavonoid compounds, all individual anthocyanins showed a decreased trend. Only in the blueberry pomace fermented by AN, all anthocyanidins exhibit a rising trend. After SSF, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenylpicrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) radical scavenging abilities were increased by up to 33.56, 59.89, and 87.82%, respectively. Moreover, the simulated gastrointestinal digestion system revealed that SSF improved the bioaccessibility of polyphenolic compounds. Compared with other strains, LA, LP, and AN showed better excellent capacities for metabolizing polyphenolic compounds, which led to a greater increase in antioxidant activity and bioaccessibility in fermented blueberry pomace.

Abstract Background Undergraduate medical (UM) students faced the difficulties inherent in medical careers due to the coronavirus (COVID-19) outbreak. Thus, imperative containment measures might affect UM students’ career intentions. Information on the factors that may be associated with these students’ career change intentions is limited. Methods We conducted a cross-sectional survey in August 2020 to investigate the impact of the COVID-19 pandemic on career intention and the associated factors in UM students. Univariate analyses and logistic regression analysis were performed to identify said factors. Results A total of 2040 medical students from the Hubei University of Medicine were surveyed. Univariate analyses showed that grade, attitude towards healthcare, and the degree of the COVID-19 pandemic’s impact on the students’ lives were associated with changes in career choice (P

Abstract The global expansion of forest plantations at the expense of natural forests, especially old‐growth forests, raises concerns about habitat loss and a decline in ecosystem services. Natural regeneration of second‐growth forests with minimal human assistance has been suggested as a cost‐effective way to restore forests and increase forest ecosystem service potential. However, it is unclear whether natural regeneration will lead to the development of second‐growth forests similar to natural forests because most naturally regenerated second‐growth forests are still young. We present a case study of a very old second‐growth forest in southeastern China in which a forest plantation established approximately six centuries ago has now developed into an old forest with extraordinary high biodiversity levels, an immense carbon pool, and a rich culture. The forest was established in the 14th century because of a charitable contribution, became protected under the Chinese cultural norm of ‘unity between humans and the nature’, and was conserved because of the belief that the prosperity of people is closely linked to the prosperity of trees. The recent designation of the forest as a nature reserve further protects it from development despite competing land‐use demands related to recent economic growth. This case illustrates that, although human activity is the main cause for the disappearance and degradation of many forests, when human interests and cultural values align second‐growth restoration and subsequent forest conservation can lead to the successional development of old‐growth forests. Because this development takes multiple centuries, the protection of current second‐growth forests within conservation easements (e.g. nature reserves) and the reformation of culture values for the linkage of forests to human well‐being are key aspects of the continued conservation‐aided succession of second‐growth forests. A free Plain Language Summary can be found within the Supporting Information of this article.

Abstract Background Septic shock comprises a heterogeneous population, and individualized resuscitation strategy is of vital importance. The study aimed to identify subclasses of septic shock with non-supervised learning algorithms, so as to tailor resuscitation strategy for each class. Methods Patients with septic shock in 25 tertiary care teaching hospitals in China from January 2016 to December 2017 were enrolled in the study. Clinical and laboratory variables were collected on days 0, 1, 2, 3 and 7 after ICU admission. Subclasses of septic shock were identified by both finite mixture modeling and K-means clustering. Individualized fluid volume and norepinephrine dose were estimated using dynamic treatment regime (DTR) model to optimize the final mortality outcome. DTR models were validated in the eICU Collaborative Research Database (eICU-CRD) dataset. Results A total of 1437 patients with a mortality rate of 29% were included for analysis. The finite mixture modeling and K-means clustering robustly identified five classes of septic shock. Class 1 (baseline class) accounted for the majority of patients over all days; class 2 (critical class) had the highest severity of illness; class 3 (renal dysfunction) was characterized by renal dysfunction; class 4 (respiratory failure class) was characterized by respiratory failure; and class 5 (mild class) was characterized by the lowest mortality rate (21%). The optimal fluid infusion followed the resuscitation/de-resuscitation phases with initial large volume infusion and late restricted volume infusion. While class 1 transitioned to de-resuscitation phase on day 3, class 3 transitioned on day 1. Classes 1 and 3 might benefit from early use of norepinephrine, and class 2 can benefit from delayed use of norepinephrine while waiting for adequate fluid infusion. Conclusions Septic shock comprises a heterogeneous population that can be robustly classified into five phenotypes. These classes can be easily identified with routine clinical variables and can help to tailor resuscitation strategy in the context of precise medicine.

In this paper, a method of realizing voltage-mode (VM) non-inverting high-pass filter (HPF), band-pass filter (BPF), low-pass filter (LPF), and inverting low-pass filter (ILPF) transfer functions structure with two grounded capacitors and four resistors through an analytical synthesis method is presented. The synthesis structure of the VM biquadratic filter consists of a voltage proportional block and two voltage lossless integrators based on the use of current feedback operational amplifiers (CFOAs). It is demonstrated that the derived biquadratic filter structure can simultaneously realize VM HPF, BPF and ILPF transfer functions or VM BPF and LPF transfer functions at a high-input impedance terminal. The VM biquadratic filter can independently adjust the resonance angular frequency and quality factor. By slightly modifying the proposed biquadratic filter, a VM quadrature sinusoidal oscillator can be achieved. The proposed biquadratic filter and quadrature oscillator have been simulated by OrCAD PSpice and appropriate hardware has been implemented with AD844-type CFOAs. In order to reduce power consumption, reduce chip area, reduce costs, and improve system integration, integrated VM CFOA-based biquadratic filter circuits and quadrature oscillator circuits are very important. The proposed filter and quadrature oscillator have been further fabricated in 0.18 μm 1P6M CMOS process technology. The entire chip area is 0.974 mm2, including a filter chip cell and an oscillator chip cell. Under the supply voltage of ±0.9 V, the total power dissipation of the filter chip cell is 5.4 mW, and the figure-of-merit (FOM) of filter chip cell is 66.7%. The measured value of the third-order intermodulation distortion of the filter chip cell is -55.29 dBc and the third-order intercept point is 19.9 dBm. The measured phase noise of CFOA-based filter chip cell at 1 kHz offset is less than -99.76 dBc/Hz.

Soil microorganisms play a key role in soil fertility. Exploring the microbial community composition and diversity in response to cover crops is important for improving soil fertility in orchards. This study investigated how cover cropping can improve soil fertility by altering microbial community composition and the interrelations among soil microorganisms. Soil physicochemical and biological indicators and microbial community composition were evaluated after a 6-years application of cover cropping in an apple (Malus pumila cv. Fuji) orchard located on the Loess Plateau, China. Three treatments were applied: Trifolium repens treatment (TR), Lolium perenne treatment (LP), clear tillage treatment (CT). The soil of the cover crop treatments had a more complex microbial co-occurrence network than that of the clear tillage treatment; in particular, the correlations among fungi were significantly increased. Cover cropping increased the levels of soil organic matter (SOM), microbial biomass carbon (MBC), and total nitrogen (TN) in orchard soil. Changes in the fungal community were more related to microbial biomass nitrogen (MBN), TN, and carbon-nitrogen ratio (C:N). This indicates that cover cropping not only increases the diversity of soil microorganisms but also increases the interrelations between microbial groups, thereby improving the soil fertility of apple orchards on the Loess Plateau.

Nanomaterials have received increasing attentions owing to their potential hazards to the environment and human health; however, the multi-generational toxicity of graphene oxide under consecutive multi-generational exposure scenario still remains unclear. In the present study, Caenorhabditis elegans as an in vivo model organism was employed to explore the multi-generational toxicity effects of graphene oxide and the underlying mechanisms. Endpoints including development and lifespan, locomotion behaviors, defecation cycle, brood sizes, and oxidative response were evaluated in the parental generation and subsequent five filial generations. After continuous exposure for several generations, worms grew smaller and lived shorter. The locomotion behaviors were reduced across the filial generations and these reduced trends were following the impairments of locomotion-related neurons. In addition, the extended defecation cycles from the third filial generation were in consistency with the relative size reduction of the defecation related neuron. Simultaneously, the fertility function of the nematode was impaired under consecutive exposure as reduced brood sizes and oocytes numbers, increased apoptosis of germline, and aberrant expression of reproductive related genes ced-3, ced-4, ced-9, egl-1 and ced-13 were detected in exposed worms. Furthermore, the antioxidant enzyme, SOD-3 was significantly increased in the parent and filial generations. Thus, continuous multi-generational exposure to graphene oxide caused damage to the neuron development and the reproductive system in nematodes. These toxic effects could be reflected by indicators such as growth inhibition, shortened lifespan, and locomotion behavior impairment and induced oxidative response.

Abstract Background LncRNA PLAC2 has been characterized as a tumor suppressive lncRNA in glioma. We investigated the role of PLAC2 in non-small cell lung cancer (NSCLC). Methods A total of 187 NSCLC patients were admitted by The First Hospital of Jilin University from December 2010 to December 2014. All the patients were diagnosed by histopathological approaches. Transient cell transfections, RT-qPCR, invasion, and migration ability measurement, were applied for the experiments. Results PLAC2 was down-regulated, while miR-21 was up-regulated in NSCLC tissues compared to non-cancer tissues. Low PLAC2 levels in NSCLC tissues were associated with poor survival of NSCLC patients. PLAC2 and miR-21 were inversely correlated, and PLAC 2 over-expression in NSCLC cells resulted in the down-regulation of miR-21. However, miR-21 over-expression did not significantly affect PLAC2 expression. In addition, PLAC2 over-expression resulted in decreased migration and invasion rates of NSCLC cells. MiR-21 over-expression played the opposite role and attenuated the effects of PLAC2 over-expression. Conclusions In conclusion, lncRNA PLAC2 down-regulated miR-21 in NSCLC and inhibited cancer cell migration and invasion.

The tensile and compressive stresses of demagnetized specimens made of Q235 steel were tested, and magnetic signal variation characteristics under different tensile and compressive stresses were continuously recorded using a magnetic memory on-line monitoring system. The results demonstrate that the resultant magnetic field first decreases and then increases induced by tensile load and becomes stable when approaching and exceeding 0.3 times the yielding strength of the material, while the resultant magnetic field induced by compressive stress rapidly decreases in the initial stage and then fluctuates. The model for J-A magnetomechanical effect was improved by introducing different stress demagnetization terms caused by tensile and compressive stresses, and the simulation results are consistent with the experimental data, which can be used for theoretically explaining different mechanisms induced by tensile and compressive stresses.