Researchers Develop New Tools for Precise Large DNA Insertions

GAO Caixia’s group from the Institute of Genetics and Developmental Biology(IGDB)of the Chinese Academy of Sciences(CAS)has developed a new genome editing technology that achieves efficient and precise targeted insertion of large DNA segments in plants.The new technology,called prime editing-mediated recombination of opportune targets(PrimeRoot),combines an optimized dual-ePPE editor protein previously published by the group with a highly efficient tyrosine site-specific recombinase,Cre.It can achieve one-step,precise targeted insertion of large DNA segments in rice and maize with an efficiency up to 6%and has been used to successfully insert DNA segments up to 11.1 kb.

Identification of transgene insertions in two genetically modified soybeans using high throughput next generation sequencing

Genetically modified(GM) organisms are widely adopted. However, their safety assessments and control are still of special concern to the public. Identifying and localizing transgene insertion is an essentially prerequisite step. In this study, 2 independent transgene soybean lines were selected(LB4-AtDCGS-1-20-5-2 and CGS-ZG11) as typical cases. Both lines contained expression cassette of At-DCGS that encoding a feedback-insensitive cystathionine gamma-synthase to produce higher level methionine(Met). LB4-AtDCGS-1-20-5-2 was whole genome sequenced with one paired-end 500 bp library and two mate-paired 1 kb and 2 kb libraries using Illumina HiSeq sequencing platform. CGS-ZG11 was sequenced with only one paired-end 500 bp library. Both genomes were assembled,and 2 scaffold sequences(1 for each line) were screened out by aligning with transgene.Then the transgene insertion and its flanking regions in soybean genome were further identified and confirmed by PCR cloning and Sanger sequencing. Results showed that these 2 transgene lines had single copy of inserted transgene. Their transgene insertion contents were identified, which facilitates further safety assessment. These results indicated that genome assembly using high throughput sequencing is a powerful tool for identifying transgene insertions, even with limited knowledge.

A Novel Insertion Solution for the Travelling Salesman Problem

The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine.The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and NNH.This guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match tothe optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing currentinsertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also createsnew possibilities for progress in heuristic design and optimization methodologies.

Enhancing hydrogen evolution and oxidation kinetics through oxygen insertion into nickel lattice

Nickel-based materials,including metallic Ni and Ni oxide,have been widely studied in the exploration of non-precious-metal hydrogen electrocatalysts,but neither pure Ni nor NiO is ideal for the hydrogen evolution reaction(HER)and hydrogen oxidation reaction(HOR).In this paper,an oxygen insertion strategy was applied on nickel to regulate its hydrogen electrocatalytic performance,and the oxygen-inserted nickel catalyst was successfully obtained with the assistance of tungsten dioxide support(denoted as O-Ni/WO_(2)).The partial insertion of oxygen in Ni maintains the face-centered cubic arrangement of Ni atoms,simultaneously expanding the lattice and increasing the lattice spacing.Consequently,the adsorption strength of^(*)H and^(*)OH on Ni is optimized,thus resulting in superior electrocatalytic performance of0-Ni/WO_(2)in alkaline HER/HOR.The Tafel slope of O-Ni/WO_(2)@NF for HER is 56 mV dec^(-1),and the kinetic current density of O-Ni/WO_(2)for HOR reaches 4.85 mA cm^(-2),which is ahead of most currently reported catalysts.Our proposed strategy of inserting an appropriate amount of anions into the metal lattice could provide more possibilities for the design of high-performance catalysts.

Esophageal inserted subclavian catheter:a rare complication

Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemakers in intensive care units and all specialties,from anesthesia to emergency medicine,for the treatment of trauma and hemodynamically unstable pediatric and adult patients.[1,2]Complications have been observed in more than 15% of patients who underwent CVC.Mechanical,infectious,and thrombotic complications have been reported in 5%–19%,5%–26%,and 2%–26% of patients,respectively.[3] Malposition,on the other hand,is common in subclavian catheter insertion and is usually associated with an initially misplaced guidewire.[4]

Reversible Optical Isolators and Quasi-Circulators Using a Magneto-Optical Fabry-Pérot Cavity

Nonreciprocal optical devices are essential for laser protection,modern optical communication and quantum information processing by enforcing one-way light propagation.The conventional Faraday magneto-optical nonreciprocal devices rely on a strong magnetic field,which is provided by a permanent magnet.As a result,the isolation direction of such devices is fixed and severely restricts their applications in quantum networks.In this work,we experimentally demonstrate the simultaneous one-way transmission and unidirectional reflection by using a magneto-optical Fabry-Pérot cavity and a magnetic field strength of 50 mT.An optical isolator and a three-port quasi-circulator are realized based on this nonreciprocal cavity system.The isolator achieves an isolation ratio of up to 22 dB and an averaged insertion loss down to 0.97 dB.The quasi-circulator is realized with a fidelity exceeding 99% and an overall survival probability of 89.9%,corresponding to an insertion loss of~0.46 dB.The magnetic field is provided by an electromagnetic coil,thereby allowing for reversing the light circulating path.The reversible quasi-circulator paves the way for building reconfigurable quantum networks.

An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica

Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species.

A 9.5-kb deletion in the 1st intron of OsMADS51 enhances temperature sensitivity in rice

Temperature is an important environmental factor affecting heading date of rice.Despite its importance,genes responsible for temperature-sensitive heading in rice have remained elusive.Our previous study identified a quantitative trait locus qHd1 which advances heading date under high temperatures.A 9.5-kb insertion was found in the first intron of OsMADS51 in indica variety Zhenshan 97(ZS97).However,the function of this natural variant in controlling temperature sensitivity has not been verified.In this study,we used CRISPR/Cas9 to knock out the 9.5-kb insertion in ZS97.Experiments conducted under cotrolled conditions in phytotrons confirmed that deletion increased temperature sensitivity and advanced heading by downregulating the expression level of OsMADS51.One-hybrid assays in yeast,ChIP-quantitative polymerase chain reaction,electrophoretic mobility shift,and luciferase-based transient transactivation assays collectively confirmed that OsMADS51 affects heading date by regulation of heading date gene Ehd1.We further determined that the long non-coding RNA HEATINR is generated from the first intron of OsMADS51,offering an explanation for how the 9.5-kb insertion affects temperature sensitivity.We also found that OsMADS51 was strongly selected in early/late-season rice varieties in South China,possibly accounting for their strong temperature sensitivity.These insights not only advance our understanding of the molecular mechanisms underlying the temperature-responsive regulation of heading date in rice but also provide a valuable genetic target for molecular breeding.

Appropriate Combination of Crossover Operator and Mutation Operator in Genetic Algorithms for the Travelling Salesman Problem

Genetic algorithms(GAs)are very good metaheuristic algorithms that are suitable for solving NP-hard combinatorial optimization problems.AsimpleGAbeginswith a set of solutions represented by a population of chromosomes and then uses the idea of survival of the fittest in the selection process to select some fitter chromosomes.It uses a crossover operator to create better offspring chromosomes and thus,converges the population.Also,it uses a mutation operator to explore the unexplored areas by the crossover operator,and thus,diversifies the GA search space.A combination of crossover and mutation operators makes the GA search strong enough to reach the optimal solution.However,appropriate selection and combination of crossover operator and mutation operator can lead to a very good GA for solving an optimization problem.In this present paper,we aim to study the benchmark traveling salesman problem(TSP).We developed several genetic algorithms using seven crossover operators and six mutation operators for the TSP and then compared them to some benchmark TSPLIB instances.The experimental studies show the effectiveness of the combination of a comprehensive sequential constructive crossover operator and insertion mutation operator for the problem.The GA using the comprehensive sequential constructive crossover with insertion mutation could find average solutions whose average percentage of excesses from the best-known solutions are between 0.22 and 14.94 for our experimented problem instances.

Lower extremity peripherally inserted central catheter placement ectopic to the ascending lumbar vein:A case report

BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients with superior vena cava syndrome(SVCS).We report the case of a patient with a lower extremity PICC ectopic to the ascending lumbar vein,to indicate and verify PICC catheterisation in the lower extremity is safe and feasible.And hope to provide different per-spectives for clinical PICC venipuncture to get the attention of peers.CASE SUMMARY On 24 August 2022,a 58-year-old male was admitted to our department due to an intermittent cough persisting for over a month,which worsened 10 d prior.Imaging and laboratory investigations suggested the patient with pulmonary malignancy and SVCS.Chemotherapy was not an absolute contraindication in this patient.Lower extremity venipuncture is the preferred technique because administering upper extremity venous transfusion to patients with SVCS can exacerbate oedema in the head,neck,and upper extremities.The patient and his family were informed about the procedure,and informed consent was obtained.After successful puncture and prompt treatment,the patient was discharged,experiencing some relief from symptoms.CONCLUSION Inferior vena cava catheterisation is rare and important for cancer patients with SVCS,particularly in complex situations involving ectopic placement.

Tubular Heat Enhancement Using Twisted Tape Inserts with Large Holes

Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fillers inside the tubes to enhance heat transfer.This investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting factor.In the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular cross-section.The turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was constructed.The findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as well.Additionally,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably higher.Additionally,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube values.The maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated.

Treatment of benign rectal stricture caused by repeated anal insertion by endoscopy and balloon dilation:A case report

BACKGROUND Benign rectal strictures can be categorized as primary(disease-related)and secondary(surgical anastomosis-related).Secondary strictures arise from surgical complications,whereas primary strictures have diverse etiologies,including various inflammatory conditions.Benign strictures are usually managed by surgery and endoscopy.We present an unusual etiology of benign rectal stricture caused by the repeated insertion of foreign objects into the rectum for sexual purposes,resulting in rectal injury and subsequent chronic inflammation.CASE SUMMARY A 53-year-old man presented to the outpatient clinic of the Colorectal Surgery Department with symptoms of chronic constipation and bloody stools.The patient previously experienced rectal injury due to foreign object insertion for sexual purposes.Colonoscopy revealed benign circumferential narrowing of the rectum.He underwent treatment by endoscopic argon plasma coagulation and balloon dilation and follow-up as an outpatient for 4 months.A colonoscopy at the end of the follow-up period revealed no evidence of rectal stricture relapse.CONCLUSION A history of rectal injury,followed by chronic inflammation,should be considered in patients with benign rectal strictures.Management with endoscopic argon plasma coagulation and balloon dilation can prevent the need for surgical resection of benign rectal strictures.

Investigation of Fracture Strength of Current Post Materials (Peek, Fiber, Cast Metal) in Different Ferrule Conditions

Aim: The fracture resistance of the post materials used nowadays significantly impacts the fracture type of the post material. The current study aimed to examine the impact of the fracture resistance of PEEK posts, whose use as a post material has not yet become widespread, on the fracture pattern that will occur. Materials and Methods: Sixty-six extracted upper central incisor human teeth were used in the study. Six groups of posts were produced from metal, fiber, and PEEK materials (n = 11). Afterward, the fracture resistance test was applied to the samples. Samples were classified according to fracture type as repairable or irreparable. The ANOVA and test were used in statistical analysis. Post-hoc tests were carried out using Tukey’s and Tamhane’s T2 tests. On the other hand, Pearson’s chi-square test and the Fisher-Freeman-Halton test were conducted for comparisons between categorical variables. The statistical significance level was accepted as p Results: According to the fracture resistance test results, the groups where metal personal posts were used displayed higher fracture resistance in comparison with all other groups. According to the results of the optical microscope examination, the incidence of repairable fractures was significantly higher in the PEEK post group with ferrule preparation (p 0.05). Conclusion: In the absence of the ferrule effect, fractures are catastrophic, regardless of the material used. The use of PEEK as a post material contributes to keeping fractures at a repairable level.

Natural Gas Power Plants in the System Security Role—The Situation and Solutions in Brazil

This study aims to apply a methodology to analyze the regulatory obstacles for the development of thermal power plants in a country. The study uses Brazil as an application case, although mostly of the findings can be useful to other countries. It also discusses other policies and actions by the government that may contribute to the growth of natural gas-fired power plants. Using deductive and comparative research methods, the first part of this method focuses on the stage of thermoelectric power generation in Brazil. The subsequent sections present the role of the integration of gas and electricity sectors, the main obstacles to the expansion of natural-gas power generation, how the country has deal with the expansion of natural-gas power generation, as well as how other obstacles has been faced. In raising the research question, when comparing the research results of selected countries, it should be noticed the impact that the experience and lessons elsewhere have had on policies formulation on Brazil. Our conclusions pointed out that adequate policies for the natural gas-electricity Brazilian market integration make advisable the unification of electricity and natural gas agencies. We recommended developing a mathematical model to support decision-making on natural gas and electricity integration.

Current Topics in Acute Abdomen: Causes, Diagnostics, and Emerging Therapies

Acute abdomen is a serious clinical condition that requires immediate attention due to its association with intense pain and rapid progression. This article reviews important aspects of the causes, diagnostics, and treatments of acute abdomen. The research highlights the diversity of etiologies, ranging from the most common, such as acute appendicitis, to the less frequent, such as intestinal perforations by foreign bodies. Complex diagnostic methods, including clinical examinations and imaging such as computed tomography, are essential to guide accurate diagnosis, given the overlap of symptoms among different conditions. Therapeutic approaches range from conservative treatments with clinical observation and antibiotic therapy to urgent surgical interventions, such as appendectomy and cholecystectomy. Laparoscopy stands out as a promising approach, offering advantages in terms of recovery and post-operative morbidity. However, the impact of the COVID-19 pandemic has brought additional challenges to the diagnosis and treatment of acute abdomen, with delays and difficulties in accessing healthcare. This review underscores the importance of a multidisciplinary approach and constant updates among healthcare professionals in addressing acute abdomen, aiming for accurate diagnoses and appropriate therapeutic interventions to improve clinical outcomes and reduce morbidity and mortality associated with this complex clinical condition.

放疗前后鼓室置管治疗鼻咽癌伴分泌性中耳炎的疗效对比观察

目的评估放疗前后鼓室置管对行放疗的鼻咽癌伴分泌性中耳炎(OME)患者的治疗价值。方法回顾性分析2017年7月~2022年2月重庆大学附属涪陵医院确诊的鼻咽癌伴OME行放疗的49例患者,根据鼓室置管时机的不同将纳入病例分为观察组和对照组。观察组(n=21例)在放疗前即行鼓室置管,对照组(n=28例)在放疗后再行鼓室置管,对比分析两组患者的治疗效果、生活质量及远期并发症等因素。生活质量评估指标主要包括:听力改善(纯音听阈气导AC提升值)、耳鸣改善(THI耳鸣残疾评估量表得分)及咽鼓管功能(ETDQ-7咽鼓管功能障碍评分)。结果随访时间超过1年,观察组总有效率为81.0%(17/21),对照组总有效率为75.0%(21/28),差异无统计学意义(χ^(2)=0.022,P>0.05);观察组AC提升值为17.57±8.483,对照组AC提升值为19.86±5.848,差异无统计学意义(t=-1.117,P>0.05);观察组治疗后THI得分0.95±3.390,对照组THI得分为2.50±4.948,差异无统计学意义(t=-1.180,P>0.05);观察组治疗后ETDQ-7得分为9.86±6.027,对照组ETDQ-7得分为9.36±2.947,差异无统计学意义(t=0.383,P>0.05);远期并发症如化脓性中耳炎、鼓膜穿孔、耳道溢液等,观察组的发生率为19.1%(4/21),对照组发生率为25.0%(7/28),差异无统计学意义(χ^(2)=0.022,P>0.05)。结论鼻咽癌伴OME在放疗前或放疗后行鼓室置管治疗效果均较好,并有效改善患者听力、耳鸣和咽鼓管功能,但两组无明显差异且均有不低的远期并发症发生,因此放疗前不宜行不必要的鼓室置管。

Velamentous Cord Insertion: Interest of Antenatal Diagnosis and Review of the Literature

Velamentous insertion of the umbilical cord corresponds to the insertion of the cord directly on amniotic membranes. It is a rare situation whose frequency varies from 0.5% to 1.69% of single pregnancies. It must be diagnosed during the morphological ultrasound of the 2nd trimester, actively looking for the association with a vasa previa, due to the risk of fetal haemorrhagic threat. We report an antenatal diagnosis of velamentous cord insertion and its management with literature review.

Unified Control Theory from PID to ACPID

To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering.

耳内窥镜下鼓膜置管联合腺样体切除术与鼓膜穿刺治疗分泌性中耳炎患儿的临床疗效比较

目的探讨耳内窥镜下鼓膜置管联合腺样体切除术治疗分泌性中耳炎(OME)患儿的临床疗效。方法选取2021年1月~2022年3月SOM患儿120例,按术式分为穿刺组(n=60)和置管组(n=60),穿刺组给予耳内窥镜下鼓膜穿刺联合腺样体切除术,置管组给予耳内窥镜下鼓膜置管联合腺样体切除术,比较两组积液消退时间、听觉脑干诱发电位(ABR)阈值、ABRⅠ波潜伏期、干扰素γ(IFN-γ)、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)、治疗效果以及并发症。结果置管组积液消退时间显著低于穿刺组,差异有统计学意义(P<0.05);穿刺组和置管组术后ABR、ABRⅠ波潜伏期、IFN-γ、IL-6和TNF-α均显著低于术前(P均<0.05);置管组术后ABR、ABRⅠ波潜伏期、IFN-γ、IL-6和TNF-α均显著低于穿刺组,差异有统计学意义(P均<0.05);置管组治疗有效率显著高于穿刺组,差异有统计学意义(P<0.05);置管组并发症发生率显著低于穿刺组,差异有统计学意义(P<0.05)。结论耳内窥镜下鼓膜置管联合腺样体切除术可有效改善SOM患儿听力及炎症,有利于提高疗效,且可减少并发症,值得临床推广。

An Approach for Searching Insertions in Bacterial Genes Leading to the Phase Shift of Triplet Periodicity

The concept of the phase shift of triplet periodicity （TP） was used for searching potential DNA insertions in genes from 17 bacterial genomes. A mathematical algorithm for detection of these insertions has been developed. This approach can detect potential insertions and deletions with lengths that are not multiples of three bases, especially insertions of relatively large DNA fragments （〉 100 bases）. New similarity measure between triplet matrixes was employed to improve the sensitivity for detecting the TP phase shift. Sequences of 17,220 bacterial genes with each consisting of more than 1,200 bases were analyzed, and the presence of a TP phase shift has been shown in -16% of analysed genes （2,809 genes）, which is about 4 times more than that detected in our previous work. We propose that shifts of the TP phase may indicate the shifts of reading frame in genes after insertions of the DNA fragments with lengths that are not multiples of three bases. A relationship between the phase shifts of TP and the frame shifts in genes is discussed.