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Operational feasibility study of stagnation pressure reaction control for a mid-caliber non-spinning projectile

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Defence Technology（防务技术） 2023年第6期24卷 109-121页

作者： f.Bouquet The Netherlands Organisation for Applied Scientific Research Oude Waalsdorperweg 632597 AK Den Haagthe Netherlands

Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering targets.The Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning projectiles.In a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test object.In an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control force.furthermore,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering targets.This work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier study.It illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation ammunition.This research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.

关键词： Supersonic projectile feasibility study Ram air Stagnation pressure reaction control Simulation Attitude control

Cancer exploits a late premetazoan gene module conserved in the human genome

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Genes & Diseases 2023年第4期10卷 1136-1138页

作者： Vladimir f.Niculescu Kirschenweg 1 Diedorf 86420Germany

from an evolutionary perspective,the human cancer genome is based on an ancient gene module developed by the common ancestor of the Amoebozoa,Metazoa,and fungi(AMf).^(1)The transition phase to multicellularity(premetazoan period)was a rather long period of evolu-tionary attempts and failures.During this time,suppressor genes were evolved to deactivate the G+S cell system inherited from the AMf ancestor.

关键词： ancient evolved Cancer

Hebbian plasticity:the elusive missing link at the heart of Alzheimer’s disease pathogenesis?

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Neural Regeneration Research 2023年第1期18卷 123-124页

作者： Alexander f.Jeans Department of Pharmacology University of OxfordOxfordUK

The amyloid cascade hypothesis of Alzheimer’s pathogenesis:The amyloid cascade hypothesis of Alzheimer’s disease(AD)pathogenesis will shortly celebrate its thirtieth birthday(Hardy and Higgins,1992).Based on abundant genetic and biochemical evidence,it proposes that deposition of the amyloid-β(Aβ)peptide in brain parenchyma is an essential upstream trigger in AD pathogenesis that drives a cascade of events,specifically including the recruitment and pathological hyper-phosphorylation of the micro-tubule-associated protein tau,that culminate in derangement of synaptic function and,eventually,neuronal death.

关键词： pathogenesis Alzheimer eventually

Identification of Hammerstein-Wiener model with discontinuous input nonlinearity

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Science China(Information Sciences) 2023年第12期66卷 33-47页

作者： A.BROURI f.Z.EL MANSOURI f.Z.CHAOUI C.ABDELAALI f.GIRI ENSAM Moulay Ismail University ENSAM University Mohammed V Normandie Universite

This paper deals with the identification of Hammerstein-Wiener models with an irregular function in the input block. These models comprise a set of linear segments. The linear time invariant(LTI) block may be parametric or nonparametric. The nonlinearity of the output can be any continuous function of arbitrary shape; it is not necessarily assumed to be invertible. Subsequently, sine inputs will be used to identify the system parameters. first, the output nonlinearity is determined by filtering the system output and varying the phase of a given reference sine signal; second, the parameters of the linear block can be determined for any frequency; and finally, the input nonlinearity can be obtained by changing the offset and amplitude of the input sine signal.

关键词： nonlinear systems nonlinear systems identification Hammerstein-Wiener models discontinuous nonlinearities hard nonlinearities

Antibacterial and anti-parasitic activities of Terfezia claveryi methanolic extract against some common pathogenic agents of infectious diarrhea

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Asian Pacific Journal of Tropical Biomedicine 2022年第5期12卷 216-222页

作者： Sultan f Alnomasy Department of Medical Laboratories Sciences College of Applied Medical SciencesShaqra UniversityAl-Quwayiyah 19257Saudi Arabia

Objective:To assess the antidiarrheal effects of Terfezia claveryi methanolic extract against Escherichia coli,Salmonella typhimurium,Shigella flexneri,and Giardia lamblia.Methods:Antibacterial effects of the Terfezia claveryi methanolic extract were carried out by determining the minimum inhibitory concentration(MIC)and minimum bactericidal concentration through micro broth dilution technique.furthermore,reactive oxygen species production and protein leakage were evaluated.To evaluate the in vitro anti-giardial effects of Terfezia claveryi methanolic extract,Giardia lamblia WB(ATCC®30957)trophozoites were treated with various concentrations of Terfezia claveryi methanolic extract for 10-360 min.In addition,the plasma membrane permeability of trophozoites treated with Terfezia claveryi methanolic extract was determined.The cytotoxicity effects of Terfezia claveryi methanolic extract against normal(HEK293T)and cancer(MCf-7)cells were also assessed using the MTT assay.Results:The MIC and minimum bactericidal concentration of Terfezia claveryi methanolic extract against bacterial strains were in the range of 0.52-1.04 and 1.04-2.08 mg/mL,respectively.The results revealed that reactive oxygen species production and protein leakage were significantly increased after the bacteria were treated with the Terfezia claveryi methanolic extract,especially at 1/3 and 1/2 MICs(Pfurthermore,Terfezia claveryi methanolic extract decreased the viability of Giardia lamblia trophozoites in a dose-dependent manner.Terfezia claveryi methanolic extract at 1,2,and 4 mg/mL resulted in 100%mortality in Giardia lamblia trophozoites after 360,240,and 120 min,respectively.Moreover,Terfezia claveryi methanolic extract altered the permeability of plasma membrane of Giardia lamblia trophozoites by increasing the concentration.MTT assay revealed that the 50%cytotoxic concentrations values for HEK293T and MCf-7 cells were 4.32 mg/mL and 6.40 mg/mL,respectively,indicating that Terfezia claveryi methanolic extract had greater cytotoxicity ag

关键词： Terfezia claveryi Shigellosis Giardiasis Herbal medicines Infectious diarrhea Cellular mechanisms Cytotoxicity Microbiology

Lattice vibration,optical,and mechanical properties of aluminum phosphide (AlP) compound under the influence of temperature

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Optoelectronics Letters 2023年第8期19卷 472-475页

作者： Ibtisam f Al Maaitah Applied Physics Department Faculty of ScienceTafila Technical UniversityP.O.Box 179TafilaJordan

We have studied the lattice vibrations,optical and mechanical characteristics of the zinc-blende aluminum phosphide(Al P) compound.Investigations have been done into the effect of temperature on refractive index,optical dielectric constant,static dielectric constant,longitudinal and transversal sound velocities,reflectivity,susceptibility,phonon frequencies,micro-hardness,ionicity,and transverse effective charge.Al P is a wide-indirect band gap semiconductor and has a wide range of uses in high-performance optoelectronic devices,such as the manufacturing of infrared photo-detectors and light-emitting diodes.It’s important to know the physical properties of semiconductor materials,like the Al P compound,to develop new technologies and devices.The calculations were carried out using the empirical pseudo-potential method(EPM).Comparative analysis with the existing experiment and other theoretical calculations reveals a satisfactory level of agreement.

关键词： compound optical Lattice

A comment on the article of Zoran Ivanovic and Marija Vlaski-Lafarge(2022):On cancer,stemness and deep evolutionary homologies

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Genes & Diseases 2023年第4期10卷 1139-1140页

作者： Vladimir f.Niculescu Kirschenweg 1 Diedorf 86420Germany

The comment of Ivanovic and Vlaski-Lafarge on my article“Cancer genes and cancer stem cells in tumorigenesis:Evolutionary deep homology and controversies”opens up a welcome discussion on the evolutionary history of cancer.The authors have appreciative words about my work,for which I am very grateful.At this point,I would like to contribute a few words on polyploidy,cancer genes,age,and colonial organization.

关键词： cancer Cancer evolutionary

Photometric Investigation of Contact Binary DY Cet Based on TESS Data

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Research in Astronomy and Astrophysics 2022年第5期22卷 121-128页

作者： M.f.Yildirim Canakkale Onsekiz Mart University Astrophysics Research Center and Ulupinar Observatory17020CanakkaleTurkey Canakkale Onsekiz Mart University Department of Electricity and EnergyCan Vocational School17400CanakkaleTurkey

We present a photometric analysis of the Transiting Exoplanet Survey Satellite(TESS)light curve of contact binary system DY Cet and the behavior of its orbital period variation.The light curve and published radial velocity data analysis was performed using the Wilson-Devinney code.As a result of simultaneous analysis of the light curve with radial velocity data,the masses and radii of the system’s components were determined as M_(1)=1.55±0.02 M_(⊙),M_(2)=0.55±0.01 M_(⊙) and R_(1)=1.51±0.02 R_(⊙),R_(2)=0.95±0.02 R_(⊙),respectively.The degree of contact(f)and mass ratio(q)of the system were determined as 23%and 0.355±0.012,respectively.Orbital period analysis of DY Cet was conducted for the first time in this study.It was observed that the orbital period has a sinusoidal change with decreasing parabola.To explain the orbital period change,mass transfer between components is proposed with the assumption of conservative mass,and the transfer rate was calculated to be dM/dt=1.1×10^(-7) M_(⊙)yr^(-1).A possible third component is suggested for explaining the sinusoidal change,and the mass of the unseen component was determined as 0.13 M_(⊙).The age of the DY Cet system was estimated as 3.77 Gyr.

关键词： stars eclipsing binary stars-stars fundamental parameters of stars- stars individual (DY Cet)

Cancer genes and cancer stem cells in tumorigenesis:Evolutionary deep homology and controversies

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Genes & Diseases 2022年第5期9卷 1234-1247页

作者： Vladimir f.Niculescu Kirschenweg 1 Diedorf 86420Germany

In the past,contradictory statements have been made about the age of cancer genes.While phylostratigraphic studies suggest that cancer genes emerged during the transitional period from unicellularians(UC)to early metazoans(EM),life cycle studies suggest that they arose earlier.This controversy could not be resolved.Phylostratigraphic methods use data from somatic tumor gene collections containing or lacking polyploidy genes(PGCC genes)and compare them to genes from evolutionary node taxa.I analyze whether the selected taxa are suitable to resolve the above contradiction or not.Both cancer and amoebae life cycles have a reproductive asexual germline that produces germline stem cells(GSCs)and somatic cell lines that cannot.When the germline loses its reproductive function,the soma-to-germ transition forms a new reproductive germline.The reproductive polyploidy of cancer is homologous to the reproductive polyploidy of unicellular cysts.PGCCs repair DNA defects,reorganize the involved genome architecture and produce new GSCs.The present study refutes the dogma of the early metazoan origin of cancer.Cancer has a unicellular life cycle that was adopted by early metazoans to rescue themselves from evolutionary dead ends.Early metazoans controlled the unicellular life cycle through suppressor and anti-suppressor genes that could suspend or reactivate it.They are the archetypes of tumor suppressor genes and oncogenes.Cells of mammalians and humans that reach a similar impasse as early metazoans can reactivate the conserved life cycle of unicellularians.

关键词： Cancer Entamoeba Gene age Life cycle Polyploidy CSCs EMT PGCC