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The COVID-19 Pandemic: Present or Gone, Where Do Adolescents Stand?

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Advances in Infectious Diseases 2024年第2期14卷 374-386页

作者： Ifueko Enadeghe Ayebo Sadoh Emmanuel u. Eyo-Ita Phillip O. Abiodun Department of Child Health University of Benin Teaching Hospital Benin City Nigeria Institute of Child Health University of Benin Benin City Nigeria

Introduction: The initial global response to the SARS-CoV-2 pandemic focused on adults as adolescents mainly had subclinical infections. Adolescents, however, could transmit the virus and hence be a risk to the elderly, young children and immunocompromised. Adolescents are also at risk of long-term complications. This study sought to determine the prevalence of antibodies to SARS-CoV-2 among adolescents in Southern Nigeria, and to determine the association between SARS-CoV-2 seropositivity and age, gender, socioeconomic class, school type and nutritional status. Methods: This descriptive cross-sectional study was carried out in Edo state of southern Nigeria. We recruited 270 in-school adolescents aged 10 - 19 years. A WHO-adapted, pre-tested questionnaire was used to obtain data on participant history and risk factors. The questionnaire was interviewer-administered. Adolescents whose parents gave consent were recruited through a multi-stage randomized sampling method. Capillary blood for the assay was collected and analysed using a lateral-flow immunoassay device. The primary outcome was serostatus of the study. The positive predictors of serostatus were finally determined using a multiple logistics regression model. Statistical significance was set at p Results: The seroprevalence of SARS-CoV-2 was 45.9%. IgM antibodies were found in 5.6% of participants. Older adolescents had higher seropositivity rates than younger adolescents (2 = 8.101, p = 0.017). There was no association between gender and seropositivity. Adolescents in public schools were more likely to be seropositive than those in private schools (2 = 25.242, p = 0.001). A higher seroprevalence was noticed among study participants in the lower socioeconomic class (x2 = 6.928, p = 0.031), and those in overcrowded classes. (2 = 79.303, p = 0.001). Conclusion: This study showed a high seroprevalence of SARS-CoV-2 among in-school adolescents. Behavioural change communication on SARS-CoV-2, vaccination of adole

关键词： Pandemic Adolescents Seroprevalence COVID-19

Prospective cohort study on facial profile changes in infants with Robin sequence and healthy controls

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World Journal of Pediatrics 2024年第6期20卷 581-589页

作者： Cornelia Wiechers Julian Sowula Karen Kreutzer Christoph E.Schwarz Christina Weismann Michael Krimmel Christian f.Poets Bernd Koos Department of Neonatology Tuebingen University HospitalCalwerstrasse 772076 TuebingenGermany Center for Cleft Lip Palate and Craniofacial MalformationsTuebingen University HospitalTuebingenGermany Department of Orthodontics Tuebingen University HospitalTuebingenGermany Department of Oral and Maxillofacial Surgery Tuebingen University HospitalTuebingenGermany

Background Various conservative and surgical approaches exist to treat Robin sequence(RS),but their effects on facial profile and mandibular catch-up growth are unclear.A functional treatment concept,used in our centre for 25 years,includes an individualized palatal plate with a velo-pharyngeal extension and intensive feeding *** We performed a prospective study to objectively describe facial profiles in infants with RS treated with the above *** with isolated RS were admitted to our tertiary perinatal and national referral centre for craniofacial malformations between May 2018 and Nov *** with RS received 3D-photographs during clinically indicated *** controls were recruited from Dec 2018 to Sep 2019 and received 3D-photographs every 3 *** digitally measured jaw index(JI),defined as alveolar overjet(O)x maxillary arch(u)/mandibular arch(L),and the soft tissue reference points A’-point,Nasion’,B’-point angle(ANB’),describing the relative position of maxilla to mandible,were *** mixed models were used to examine time trajectories in JI and ANB’.Results A total of 2073D images,obtained in 19 infants with RS and 32 controls,were *** and ANB’decreased over time in both groups[for JI−0.18(95%CI−0.25 to−0.10);for ANB’:−0.40°per month[(95%CI−0.48 to−0.32)]]but remained lower in controls[for JI−2.5(95%CI−3.2 to−1.8);for ANB’-1.7°(95%CI−2.4 to−1.0)].Also,the ANB’model showed a significant effect of the interaction term diagnosis x *** Based on longitudinal 3D images,we describe changes in objective parameters of facial profile in infants with and without RS during the first year of *** findings indicate catch-up growth in infants treated for RS.

关键词： Infant Mandibular catch-up growth Pre-epiglottic Baton Plate Robin sequence Three-dimensional photography

Bulking up the Bay-Position Substituents Enables Enhanced Selectivity of C_(s)‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina f.farac Alan J.Lough Timothy P.Bender Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of functional ***,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Nc_(p))s,are desirable for this purpose yet synthetically challenging due to random mixtures of C_(s-),C_(3v-),and,in some cases,C_(1)-symmetric compounds that form during traditional statistical mixed ***,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity for the targeted C_(s)-symmetric hybrid and complete suppression of sterically crowded macrocyclic *** process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of bay-position phenylated Ph_(2)-(R_(p))_(8)Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or f)in their peripheral isoindole *** selectivity ranged between 59 and 72%with remarkable yields,significantly higher than that of conventional mixed *** findings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle ***,the incorporation of unfused phenyl groups and halogen atoms into the hybrid framework resulted in fine-tuned optical,structural,electronic,and electrochemical *** straightforward approach achieved improved selectivity and controlled narrowing of the product distribution,affording the efficient synthesis of structurally sophisticated Bsub(Pc_(2)-Nc_(1))*** then expands the library of 3-dimensionalπ-extended macrocycles for use in a range of applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

Generation of Eco-friendly and Disease-Resistant Channel Catfish(Ictalurus punctatus)Harboring the Alligator Cathelicidin Gene via CRISPR/Cas9 Engineering

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Engineering 2024年第8期39卷 273-286页

作者： Jinhai Wang Baofeng Su De Xing Timothy J.Bruce Shangjia Li Logan Bern Mei Shang Andrew Johnson Rhoda Mae C.Simora Michael Coogan Darshika u.Hettiarachchi Wenwen Wang Tasnuba Hasin Jacob Al-Armanazi Cuiyu Lu Rex A.Dunham School of fisheries Aquacultureand Aquatic SciencesAuburn UniversityAuburnAL 36849USA

As a precise and versatile tool for genome manipulation,the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)platform holds promise for modifying fish traits of *** the aim of reducing transgene introgression and controlling reproduction,upscaled disease resistance and reproductive intervention in catfish species have been studied to lower the potential environmental risks of the introgression of escapees as transgenic *** advantage of the CRISPR/Cas9-mediated system,we succeeded in integrating the cathelicidin gene(As-Cath)from an alligator(Alligator sinensis)into the target luteinizing hormone(lh)locus of channel catfish(Ictalurus punctatus)using two delivery systems assisted by double-stranded DNA(dsDNA)and single-stranded oligodeoxynucleotides(ssODNs),*** this study,high knock in(KI)efficiency(22.38%,64/286)but low ontarget events was achieved using the ssODN strategy,whereas adopting a dsDNA as the donor template led to an efficient on-target KI(10.80%,23/213).The on-target KI of As-Cath was instrumental in establishing the lh knockout(LH^(–)_As-Cath^(+))catfish line,which displayed heightened disease resistance and reduced fecundity compared with the wild-type(WT)sibling ***,administration of human chorionic gonadotropin(HCG)and luteinizing hormone-releasing hormone analogue(LHRHa)can restore the reproduction of the transgenic fish ***,we replaced the lh gene with an alligator cathelicidin transgene and then administered hormone therapy to move towards complete reproductive control of diseaseresistant transgenic catfish in an environmentally responsible *** strategy not only effectively improves consumer-valued traits but also guards against unwanted introgression,providing a breakthrough in aquaculture genetics to confine fish reproduction and prevent the establishment of transgenic or domestic genotypes in the natural environment.

关键词： Genome editing ssODN dsDNA Antimicrobial peptide Reproductive confinement Aquaculture

Surface Water Quality Profiling using Physicochemical Parameters in Open Defecation free and Non-Open Defecation free Local Government Areas in Benue State, Nigeria

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Open Journal of Modern Hydrology 2024年第3期14卷 174-191页

作者： Moses T. Asoo Celestine u. Aguoru Innocent O. Ogbonna Hyacinth O.A. Oluma Benue State Ministry of Health Makurdi Nigeria Department of Plant Science and Biotechnology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria Department of Microbiology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria

Physicochemical parameters of surface water sources in the study of local government areas (LGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/L), SO4 (0.77 mg/L), Na (28.72 mg/L), Ca (28.94 mg/L), Mg (17.50 mg/L), Cl (11.65 mg/L), TSS (6.27 mg/L), TDS (104.23 mg/L), BOD (2.83 mg/L) and f (0.87 mg/L) were below WHO standards irrespective of their defecation status. The values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTu), dissolved oxygen (DO) (5.32 mg/L), chemical oxygen demand (COD) (445.50 mg/L), K (125.06 mg/L), PO4 (0.78 mg/L) and fe (0.57 mg/L) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pollution of the water sources by organic matter.

关键词： Open Defecation Surface Water Water Quality Standard Physicochemical Parameters

Discrete time dynamics of a SIRD reinfection model

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生物数学学报:英文版 2023年第5期16卷 49-70页

作者： f.f.Eshmatov u.u.Jamilov Kh.O.Khudoyberdiev 221 School 33Feruza Street 100124 TashkentUzbekistan V.I.Romanovskiy Institute of Mathematics uzbekistan Academy of Sciences 9 University Street100174 TashkentUzbekistan AKfA university 264National Park Street Barkamol MFYYangiabad VillageQibray District 111221 Tashkent RegionUzbekistan National university of uzbekistan 4 University Street100174 TashkentUzbekistan

This paper deals with a discrete-time dynamical system generated by a modified susceptible-infected-recovered-dead model(SIRD model;nonlinear operator)in threedimensional *** introduce a novel approach that incorporates the SIRD model with the quadratic stochastic operator(QSO)that allows for real-time *** basic reproductive number Ro is *** describe the set of fixed points of the operator and demonstrate that all fixed points are ***,we study the asymptotical behavior of the trajectories of this system and show that SIRD operators havea regularity property.

关键词： Modeling quadratic stochastic operator regular operator

Effectiveness of heat and mass transfer on mixed convective peristaltic motion of nanofluid with irreversibility rate

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Communications in Theoretical Physics 2021年第10期73卷 36-46页

作者： Y Akbar f M Abbasi u M Zahid S A Shehzad Department of Mathematics COMSATS University IslamabadIslamabadPakistan Department of Mathematics COMSATS University IslamabadSahiwalPakistan

Entropy generation is one of the key features in analysis as it exhibits irreversibility of the system. Therefore, the present study investigates the entropy generation rate in a mixed convective peristaltic motion of a reactive nanofluid through an asymmetrical divergent channel with heat and mass transfer characteristics. The endorsed nanofluid model holds thermophoresis and Brownian diffusions. Mathematical modeling is configured under the effects of mixed convection, heat generation/absorption and viscous dissipation. A chemical reaction is also introduced for the description of mass transportation. The resulting system of differential equations is numerically tackled by employing the Shooting method. The findings reveal that entropy generation rises by improving the Brownian motion and thermophoresis parameters. The temperature of the nanofluid decreases due to rising buoyancy forces caused by the concentration gradient. The concentration profile increases by increasing the chemical reaction parameter. The velocity increases by enhancing the Brownian motion parameter.

关键词： peristaltic flow thermophoresis and Brownian motion mixed convection chemical reaction irreversibility nanofluid

Trace and rare-earth element geochemistry: A tool for petrogenetic and geotectonic modeling of ensimatic ortho-amphibolites from Pan-African belt of Obudu Plateau, Southeastern Nigeria

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Chinese Journal Of Geochemistry 2009年第1期28卷 19-27页

作者： ukaegbu V.u. Beka f.T. Department of Geology University of Port Harcourt Port Harcourt Nigeria

A model for the petrogenetic affinity and original geotectonic setting of ortho-amphibolites from the Obudu Plateau was tested using the distribution patterns of trace and rare-earth elements from the geochemical analyses of twelve representative amphibolite samples. Discrimination plots, normalized patterns of the incompatible trace elements against average MORB, low ratios of Ba/Nb (9–23) and Ba/Ta (130–327) and other geochemical characteristics suggest that the protoliths were dominantly of tholeiitic MORB composition. The values of the ratios of La/Ta (8.13–10.8), Rb/Sr (0.04–0.07), Th/u (mainly 4.43–5.43) and Hf/Ta (2.35–2.88) further indicate that the ortho-amphibolites demonstrate E-type MORB characteristics. These features are related to substantial ocean floor divergent tectonic boundary setting rather than marginal basin tectonic setting. This evolutionary pattern appears to be controlled by limited progressive partial melting and fractional crystallization of a single mantle source region, irrespective, however, of variations due to local source heterogeneities. The tholeiitic magmas were most probably generated by hotspot activities on the constructive plate margins and subsequently modified by subduction-related low-K tholeiitic chemistry due to narrowing of a proto oceanic basin between the West African craton and eastern Sahara plate. A likely model, therefore, is that the amphibolites of the Obudu Plateau represent ophiolitic suites with characteristics of enriched mid-ocean floor tholeiites, which were deformed and metamorphosed during a reversed plate motion involving subduction and collision within the Obudu Plateau in the Pan-African orogenic episode.

关键词： REE 微量元素地面沉陷角闪岩地球化学

Rare-earth and trace element imprints on the origin and tectonic setting of gabbro-diorite complex in the Pan-African belt of Southeast Obudu Plateau,Nigeria

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Chinese Journal Of Geochemistry 2009年第3期28卷 239-247页

作者： ukaegbu V.u. Beka f.T. Department of Geology University of Port HarcourtPort HarcourtNigeria

A gabbro-diorite plutonic complex from the Southeast Obudu Plateau, representing limited volumes of magma, was studied for its trace and rare-earth element characteristics, in an attempt to document its genetic and geodynamic history. Geochemical studies indicate that the gabbro samples are characterized by variable concentrations and low averages of such index elements as Cr (40×10-6–200×10-6; av. 80×10-6), Ni (40×10-6–170×10-6; 53.33×10-6) and Zr (110×10-6–240×10-6; 116.67×10-6); variable and high averages of Rb (3×10-6–270×10-6; 80.67×10-6), Sr (181×10-6–1610×10-6; 628.17×10-6) and u (0.14×10-6–3.46×10-6; 1.51×10-6), and fairly uniform Co (34×10-6–49×10-6; 36.33×10-6) and Sc (23×10-6–39×10-6; 34.5×10-6), while the diorite samples exhibit higher trace element compositions. The range of REE contents and distinctive chondrite-normalized patterns indicate moderate fractionation with slight positive Eu anomaly in the diorites to very low fractionation with flat patterns and slight positive Eu anomaly in the gabbros. However, the general element systematics of the samples, especially LILE (Ba, Rb, Sr, Cs and Pb), HfSE (Zr, Th, u, Hf, Mo, W, Nb and Sn), relatively immobile elements (Zr, Ni, Cr) and REE, suggests a differentiation model, involving fractional crystallization of olivine and clinopyroxene from a partial melt generated beneath an island arc complex. A possible model for the complex is therefore an island arc setting, the development of which was dominated by calc-alkaline magmatism across the Obudu Plateau.

关键词：构造环境微量元素尼日利亚辉长岩闪长岩起源高原痕迹