Modeling and simulation of recurrent phenotypic and genomic selections in plant breeding under the presence of epistasis

Recurrent selection is an important breeding method for population improvement and selecting elite inbreds or fixed lines from the improved germplasm.Recently,a computer simulation tool called QuMARS has been developed,which allows the simulation and optimization of various recurrent selection strategies.Our major objective in this study was to use the QuMARS tool to compare phenotypic recurrent,marker-assisted recurrent,and genomic selections(abbreviated respectively as PS,MARS and GS)for both short-and long-termbreeding procedures.ForMARS,twomarker selection models were considered,i.e.,stepwise(Rstep)and forward regressions(Forward).For GS,three prediction models were considered,i.e.,genomic best linear unbiased predictors(GBLUP),ridge regression(Ridge),and regression by Moore-Penrose general inverse(InverseMP).To generate genotypes and phenotypes for a given individual during simulation,one additive and two epistasis genetic models were considered with three levels of heritability.Results demonstrated that selection responses from GBLUP-based GS and MARS(Forward)were consistently greater than those from PS under the additive model,particularly in early selection cycles.In contrast,selection response from PS was consistently superior over MARS and GS under epistatic models.For the two epistasis models,total genetic variance and the additive variance component were increased in some cases after selection.Through simulation,we concluded that GS and PS were effective recurrent selection methods for improved breeding of targeted traits controlled by additive and epistatic quantitative trait loci(QTL).QuMARS provides an opportunity for breeders to compare,optimize and integrate new technology into their conventional breeding programs.

Modeling and Optimization of Ethane Steam Cracking Process in An Industrial Tubular Reactor with Improved Reaction Scheme

Ethane steam cracking process in an industrial reactor was investigated.An one-demsional(1D)steady-state model was developed firstly by using an improved molecular reaction scheme and was then simulated in Aspen Plus.A comparison of model results with industrial data and previously reported results showed that the model can predict the process kinetics more accurately.In addition,the validated model was used to study the effects of different process variables,including coil outlet temperature(COT),steam-to-ethane ratio and residence time on ethane conversion,ethylene selectivity,products yields,and coking rate.Finally,steady-state optimization was conducted to the operation of industrial reactor.The COT and steam-to-ethane ratio were taken as decision variables to maximize the annual operational profit.

Ergonomics of gastrointestinal endoscopies:Musculoskeletal injury among endoscopy physicians,nurses,and technicians

BACKGROUND Musculoskeletal injuries(MSI)have plagued endoscopists and ancillary staff for decades without any innovative and strong ergonomic guidelines.It has placed a physical and mental strain on our endoscopists and ancillary staff.We have very have limited data supporting this claim in our region and most data is supported by western literature.AIM To document the prevalence of MSI,and awareness and practices of ergonomics by endoscopists and ancillary staff.METHODS This is an observational cross-sectional study,conducted in Karachi,a city that boasts the maximum number of daily endoscopies in the country.An eleven-point self-administered questionnaire was distributed and used to evaluate MSI and ergonomic adjustments amongst three tertiary care setups in Karachi.An onsite survey via a 13-point checklist for endoscopy suite facilities was used to assess the ergonomically friendly conveniences at five tertiary care setups in Karachi.A total of 56 participants replied with a filled survey.RESULTS There were 56 participants in total with 39(69.6%)males.Pain and numbness were documented by 75%of the patients,with pain in the neck(41.1%),lower back(32.1%),shoulder(21.4%),thumb(12.5%),hand(23.2%),elbow(8.9%),and carpal tunnel syndrome(CTS)(7.1%).Of those,33.3%attributed their symptoms to endoscopy, 14.2% said that symptoms were not caused by endoscopy, and 52.4% were notcertain whether endoscopy had caused their symptoms. Twenty-one point four percent of patientshad to take time off their work, while 33.9% took medications for pain. Ergonomic modifications toprevent musculoskeletal injury, including placement of endoscopic monitor at eye level and thecardiac monitor in front, stopping the procedure to move patients, sitting while performingcolonoscopy, and navigating height-adjustable bed were used by 21.4%. Nine out of 13 ergonomicfacilities were not present in all five tertiary care hospitals. Conveniences, such as anti-fatiguemats, height-adjustable computer stations, and time out between patients were not present.CONCLUSIONThree-fourth of our endoscopists reported MSI, of which more than half were not sure orattributed this problem to endoscopy. The prevalence of MSI warrants urgent attention.

Smart Breeding Platform:A web-based tool for high-throughput population genetics,phenomics,and genomic selection

Dear Editor,In the era of big data and artificial intelligence,"smart breeding"has become a broad conceptual framework encompassing the paradigm shift of crop breeding to relying on analysis of high-throughput population genetics and phenomics data to conduct genomic selection,allowing identification and optimal use of the genetic potential in crop species(Xiao et al.,2022;Xu et al.,2022;Wang et al.,2023).Most existing tools for analyzing high-throughput breeding data require extensive computational power,complex installation processes,and command-line expertise and are therefore challenging and inconvenient for the majority of researchers and breeders(Brandies and Hogg,2021).

A gain-of-function mutation of the MATE family transporter DTX6 confers paraquat resistance in Arabidopsis

Paraquat is one of the most widely used nonselective herbicides and has elicited the emergence of para-quat-resistant weeds.However,the molecular mechanisms of paraquat resistance are not completely un-derstood.Here we report the Arabidopsis gain-of-function mutant pqt15-D with significantly enhanced resistance to paraquat and the corresponding gene PQT15,which encodes the Multidrug and Toxic Extru-sion(MATE)transporter DTX6.A point mutation at+932 bp in DTX6 causes a G311E amino acid substitution,enhancing the paraquat resistance ofpqt15-D,and overexpression of DTX6/PQT15 in the wild-type plants also results in strong paraquat resistance.Moreover,heterologous expression of DTX6 and DTX6-D in Es-cherichia coil significantly enhances bacterial resistance to paraquat.Importantly,overexpression of DTX6-D enables Arabidopsis plants to tolerate 4 mM paraquat,a near-commercial application level.DTX6/PQT15 is localized in the plasma membrane and endomembrane,and functions as a paraquat efflux transporter as demonstrated by paraquat efflux assays with isolated protoplasts and bacterial cells.Taken together,our results demonstrate that DTX6/PQT15 is an efflux transporter that confers paraquat resis-tance by exporting paraquat out of the cytosol.These findings reveal a molecular mechanism of paraquat resistance in higher plants and provide a promising candidate gene for engineering paraquat-resistant crops.

Electrochemical CO_(2) reduction to C_(2+) products using Cu-based electrocatalysts:A review

With the disruptive carbon cycle being blamed for global warming,the plausible electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to form valuable C_(2+)hydrocarbons and feedstock is becoming a hot topic.Cu-based electrocatalysts have been proven to be excellent CO_(2)RR alternatives for high energy value-added products in this regard.However,the selectivity of CO_(2)RR to form C_(2+)products via Cu-based catalysts suffers from a high overpotential,slow reaction kinetics,and low selectivity.This review attempts to discuss various cutting-edge strategies for understanding catalytic design such as Cu-based catalyst surface engineering,tuning Cu bandgap via alloying,nanocatalysis,and the effect of the electrolyte and pH on catalyst morphology.The most recent advances in in situ spectroscopy and computational techniques are summarized to fully comprehend reaction mechanisms,structural transformation/degradation mechanisms,and crystal facet loss with subsequent effects on catalyst activity.Furthermore,approaches for tuning Cu interactions are discussed from four key perspectives:single-atom catalysts,interfacial engineering,metal-organic frameworks,and polymer-incorporated materials,which provide new insights into the selectivity of C_(2+)products.Finally,major challenges are outlined,and potential prospects for the rational design of catalysts for robust CO_(2)RR are proposed.The integration of catalytic design with mechanistic understanding is a step forward in the promising advancement of CO_(2)RR technology for industrial applications.