Establishment of the critical period of severe acute pancreatitis-associated lung injury

BACKGROUND: Since respiratory dysfunction is the main cause of death in patients with severe acute pancreatitis (SAP), elucidating the critical period of acute pancreatitis-associated lung injury (APALI) is of important clinical value. This study aimed to define the risk period of APALI by a series of studies including a dynamic analysis of total water content, ultrastructure and number of type II alveolar epithelial cells, and reactive oxygen metabolites (ROMs) of lung tissue in a mouse model of SAP, and a clinical analysis of APALI patients. METHODS: ICR mice were selected to establish a SAP model. They were given 7 intraperitoneal injections of cerulein (50 mu g/kg body weight) at hourly intervals, followed by an intraperitoneal injection of lipopolysaccharide (15 mg/kg body weight). The total water content, ultrastructure, and number of type II alveolar epithelial cells, and ROMs of lung tissue were assessed before (0 hour) and after the establishment of SAP model (6 hours, 12 hours, I day, 4 days, and 7 days). In addition, we analyzed the data from 215 patients with APALI (PaO(2) <60 mmHg) treated at our hospital between January 1998 and December 2006. Statistical analyses were made using the F test. P values less than 0.05 were regarded as statistically significant. RESULTS: The total water content and ultrastructure of type II alveolar epithelial cells (mitochondria and lamellar bodies) of the lung in the SAP mice were significantly altered at 12 hours after the establishment of SAP model, and reached a maximum at I to 4 days. The number of type II alveolar epithelial cells and ROMs increased maximally at I day after the establishment of the model. Furthermore, clinical results showed that lung injury occurred at a mean of 3.1435 +/- 1.0199 days in patients with SAP. These clinical data were almost consistent with the results of the SAP model. CONCLUSION: The risk period for APALI is between the first and fourth day during the course of SAP.

Multi-Stage Fluid Charging and Critical Period of Hydrocarbon Accumulation of the Sinian Dengying Formation in Central Sichuan Basin

Objective The natural gas exploration of the Sinian reservoirs in the central Sichuan Basin has made a significant breakthrough in recent years, and has thus attracted much attention among geologists. The Sichuan Basin is known to have complicated geological settings, which has experienced multiple stages of tectonic evolution, fluid charging and hydrocarbon accumulation. This research aims to determine the geochemical characteristics of each stage of fluids, the features and time interval of fluid activity in different geologic periods, and further to restore the critical period and geological age of the hydrocarbon accumulation.

An Analysis of Critical Period Hypothesis in English Teaching

The Critical Period Hypothesis originated from biology and then was introduced into the field of linguistics. This paper introduces the concept of the Critical Period Hypothesis for language acquisition and some relevant literatures＇ research of Critical Period Hypothesis and English teaching in China as well as analyzing the research situation. From this contrast and analysis, the enlightenment from the Critical Period Hypothesis for language acquisition to English teaching in China is much easier to obtain. This paper determines that the influence of the Critical Period Hypothesis on second language acquisition and foreign language learning is still unclear.

Implications of Canadian Immersion Education for Bilingual Instruction in Chinese Kindergartens:From the Perspective of Critical Period Hypothesis

Canada is one of the countries with the most developed bilingual education in the world,while China starts bilingual education late.Such program greatly takes the advantage of critical period hypothesis and reveals its effectiveness.Learning from the advanced experience from Canada,this study investigated problems of bilingual education in Chinese kindergartens and offered suggestions correspondingly.Only when there are qualified and professional preschool teachers,suitable teaching materials,specific teaching objectives and methods,cooperation between parents and teachers,can the bilingual immersion education in Chinese kindergartens be fully developed.

Hematological and Biochemical Profile of Sickle Cell Patients in Critical and Inter-Critical Periods in Brazzaville, Republic of Congo

Introduction: Sickle cell disease is a public health problem in the Republic of Congo where the prevalence of sickle cell trait is estimated at 1.25%. The objective of this study is to describe the variations of hematological and biochemical parameters of hemolysis in sickle cell patients in critical and inter-critical periods. Methods: This is a descriptive cross-sectional study including sickle cell patients followed regularly at the National Reference Center for Sickle Cell Disease (CNRDr) from November 2019 to March 2020. A sample of 167 patients (sickle cell subjects in crisis and in steady state as well as control subjects) was randomly selected during the study period. The blood count was performed using a Sysmex-XN 350 automated system and the biochemical parameters were determined using the Cobas e 311 automated system. Statistical analysis was performed with SPSS version 22 software. Results: The study showed that the mean cholesterol level in controls was 4.16 ± 0.77 ul compared with 9.64 ± 4.34 ul in sickle cell crisis subjects. Hb and HCT levels were significantly higher in controls compared with sickle cell subjects in crisis. During crisis, total bilirubin, direct bilirubin, triglycerides, LDH, AST, and CRP were significantly elevated. Hematological parameters such as Hb and HCT were elevated in controls, while the mean WBC value and RET were higher in sickle cell patients in steady state. The mean values of the biochemical parameters were higher in sickle cell patients in steady state. Conclusion: Evaluation of the influence of sickle cell trait on biochemical and hematological parameters showed significant differences between sickle cell and control subjects.

A Study of Age in Second Language Acquisition——Based on the Critical Period Hypothesis

Age is one of the important factors which affects the second language acquisition.Since the critical period hypothesis has already been applied to study second language acquisition,though it was originally proposed to study the first language acquisi⁃tion,it has arisen many controversies.Some researchers home and abroad hold the view that age plays a critical role in learning a second language,while others point out that there is no close relationship between the age and second language acquisition.The au⁃thor will first briefly introduce the research situations about the critical period hypothesis.Then discuss the age’s influences on second language acquisition.At last,give some suggestions and advice on second language teaching and make a conclusion.

Enlightenment of the Critical Period Hypothesis for the Early English Education

Whether children should learn English as early as possible has been a controversial topic, and one of the focal point is the credibility of the critical period hypothesis.Does critical period hypothesis really exist?How does child's age factor influence English acquisition?Analyzing the problems existing in the early English education based on the critical period hypothesis theory, secondly, investigating child's characteristics and psychological characteristics based on a case study.The research results show that learning English is not the sooner the better; the emphasis is how to ensure the quality.We should Specify children's English education market, and providence environment of language acquisition, attach great importance to the interest, and give full play to children in different stages of learning advantage.Parents and society should correctly treat the early English education, reduce misunderstanding and promote the healthy development of children's English education.

Weak Centers and Local Bifurcations of Critical Periods at Infinity for a Class of Rational Systems

We describe an approach to studying the center problem and local bifurcations of critical periods at infinity for a class of differential systems. We then solve the problem and investigate the bifurcations for a class of rational differential systems with a cubic polynomial as its numerator.

Local Bifurcation of Critical Periods for a Class of Liénard Equations

In this paper, we study the local bifurcation of critical periods near the nondegenerate center （the origin） of a class of Li@nard equations with degree 2n, and prove that at most 2n - 2 critical periods （taken into account multiplicity） can be produced from a weak center of finite order. We also prove that it can have exactly 2n - 2 critical periods near the origin.

Schizophrenia risk-gene Crmp2 deficiency causes precocious critical period plasticity and deteriorated binocular vision

Brain-specific loss of a microtubule-binding protein collapsin response mediator protein-2(CRMP2)in the mouse recapitulates many schizophrenia-like behaviors of human patients,possibly resulting from associated developmental deficits in neuronal differentiation,path-finding,and synapse formation.However,it is still unclear how the Crmp2 loss affects neuronal circuit function and plasticity.By conducting in vivo and ex vivo electrophysiological recording in the mouse primary visual cortex(V1),we reveal that CRMP2 exerts a key regulation on the timing of postnatal critical period(CP)for experience-dependent circuit plasticity of sensory cortex.In the developing V1,the Crmp2 deficiency induces not only a delayed maturation of visual tuning functions but also a precocious CP for visual input-induced ocular dominance plasticity and its induction activity–coincident binocular inputs right after eye-opening.Mechanistically,the Crmp2 deficiency accelerates the maturation process of cortical inhibitory transmission and subsequently promotes an early emergence of balanced excitatory-inhibitory cortical circuits during the postnatal development.Moreover,the precocious CP plasticity results in deteriorated binocular depth perception in adulthood.Thus,these findings suggest that the Crmp2 deficiency dysregulates the timing of CP for experience-dependent refinement of circuit connections and further leads to impaired sensory perception in later life.

Multiple Bifurcations of Critical Period for a Quartic Kolmogorov Model

Our work is concerned with the bifurcation of critical period for a quartic Kolmogorov system.By computing the periodic constants carefully,we show that point(1,1)can be a weak center of fourth order,and the weak centers condition is given.Moreover,point(1,1)can bifurcate 4 critical periods under a certain condition.In terms of multiple bifurcation of critical periodic problem for Kolmogorov model,studied results are less seen,our work is good and interesting.

The biosynthesis of alarm pheromone in the wheat aphid Rhopalosiphum padi is regulated by hormones via fatty acid metabolism

Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphid alarm pheromone(AAP)is the sesquiterpene hydrocarbon(E)-β-farnesene(EβF).However,the mechanisms behind its biosynthesis and regulation remain poorly understood.In this study,we used the bird cherry–oat aphid Rhopalosiphum padi,which is an important wheat aphid,to investigate the regulatory mechanisms of EβF biosynthesis.Our results showed that EβF biosynthesis occurs during the mature embryo period and the molting period of the 1st-and 2nd-instar nymphs.Triglycerides provide the prerequisite material for EβF production and release.Based on transcriptome sequencing,RNAi analysis,hormone treatments,and quantitative measurements,we found that the biosynthesis of EβF utilizes acetyl coenzyme A produced from fatty acid degradation,which can be suppressed by juvenile hormone but it is promoted by 20-hydroxyecdysone through the modulation of fatty acid metabolism.This is the first systemic study on the modulation of EβF production in aphids.The results of our study provide insights into the molecular regulatory mechanisms of AAP biosynthesis,as well as valuable information for designing potential aphid control strategies.

Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs

According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably,

Exploring the Impact of Translanguaging on Chinese-speaking Students’Academic English Writing:Taking CET-4 as an Example

This qualitative research study attempts to discover the real thinking process of learners who are native Chinese speakers in Academic English Writing(AEW)through interviews.Introspecting an EFL learner’s thinking process in English writing is based on two theories:critical period hypothesis and translanguaging.The results of the study indicate that translanguaging has a positive impact on the English CET-4 writing of learners who lack proficiency in English.For those learners who lack proficiency in the second language,translanguaging is an effective auxiliary tool for them to complete AEW.

Viruses and autism: A Bi-mutual cause and effect

Autism spectrum disorder(ASD)is a group of heterogeneous,multi-factorial,neurodevelopmental disorders resulting from genetic and environmental factors interplay.Infection is a significant trigger of autism,especially during the critical developmental period.There is a strong interplay between the viral infection as a trigger and a result of ASD.We aim to highlight the mutual relationship between autism and viruses.We performed a thorough literature review and included 158 research in this review.Most of the literature agreed on the possible effects of the viral infection during the critical period of development on the risk of developing autism,especially for specific viral infections such as Rubella,Cytomegalovirus,Herpes Simplex virus,Varicella Zoster Virus,Influenza virus,Zika virus,and severe acute respiratory syndrome coronavirus 2.Viral infection directly infects the brain,triggers immune activation,induces epigenetic changes,and raises the risks of having a child with autism.At the same time,there is some evidence of increased risk of infection,including viral infections in children with autism,due to lots of factors.There is an increased risk of developing autism with a specific viral infection during the early developmental period and an increased risk of viral infections in children with autism.In addition,children with autism are at increased risk of infection,including viruses.Every effort should be made to prevent maternal and early-life infections and reduce the risk of autism.Immune modulation of children with autism should be considered to reduce the risk of infection.

A Review of Three Misconceptions about Age and L2 Learning(Marinova‐Todd,et al.,2000)and Comments on Stefka H.Marinova-Todd,D.Bradford Marshall,and Catherine E.Snow’s“Three Misconceptions About Age and L2 Learning.”(Hyltenstam&Abrahamsson,2001)

Age has always been an important factor in studying second language acquisition.Marinova‐Todd points out three misconceptions about research in support of CPH and disputes the existence of a Critical Period in L2 learning.Hyltenstam&Abrahamsson refutes Marinova‐Todd’s“three misconceptions”.By contrasting and comparing the views and evidence from the two papers,the present author analyzes the differences among various claims on the rate of learning and different brain organization,as well as the possible causes for the disagreements.

Changes in N-methyl-D-aspartate receptor 2A subunit expression caused by binocular form deprivation and chondroitin sulfate proteoglycan degradation

Light deprivation is known to induce a significant decrease in the percentage of N-methyi-D- aspartate receptor 2A subunit （NR2A）-expressing neurons during development. The purpose of this study was to investigate the effects of binocular form deprivation （BFD） and chondroitin sulfate proteoglycan （CSPG） degradation on NR2A expression via an immunohistochemical study, around the end of a critical developmental period. The results show that the positive staining of NR2A in the normal rat visual cortex increases gradually from postnatal 3-5 weeks （P 〈 0.05）, but the changes from 5 weeks to 7 weeks were not significant. The positive staining of NR2A following BFD in the rat visual cortex slightly increased from postnatal 3-7 weeks （P 〉 0.05）. The positive staining of NR2A in the CSPG-treated group was insignificant compared with the BFD group at the same time point from 4 weeks to 7 weeks （P 〉 0.05）. Thus, the effect of BFD on NR2A expression in the rat visual cortex was similar to that of CSPG degradation around the end of the critical developmental period.

On the Feasibility of Early-age English learning

Children's English learning in China attracts more and more people's attention and is on the tendency of starting at an early age. Under the trend of "learning English from childhood", the author has explored the Critical Period Hypothesis and discussed the younger learners' disadvantages and older learners' advantages when learning English. and concludes that early-age English learning is not feasible.

The effects of Age of Acquisition on an L2 learner’s Ultimate Attainment

This paper focuses on generalizing different theories towards the age effect on the ultimate attainment of second language learners since it has long been a controversial topic in researchers’mind.In this paper,it gives evidences on cases in favor of the Critical Period Hypothesis,which claimed the loss of language learning ability after puberty and presents counter-evidences on the successful acquisition of second language in adult learners.It has reached into a conclusion that consists the viewpoint drawn on previous analysis and confirmed the possibility in ultimate second language attainment for late learners.

Literature Review: Age Effects in the Second Language Acquisition Focusing on Morphosyntax

Age effect in second language acquisition has been a key question for a long time. It mainly focuses on the discussionabout the critical period. The thesis first introduces import hypothesis and opinions in this area and then analyzes the effects thatage has in morphosyntax area in detail. Thirdly, the analysis of Patkowski's study and Abrahamsson's study are made. Finally, itpoints out the enlightments and suggestions that the literature implies.