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Additively manufactured Ti–Ta–Cu alloys for the next-generation load-bearing implants

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International Journal of Extreme Manufacturing 2024年第1期6卷 353-374页

作者： Amit Bandyopadhyay Indranath Mitra Sushant Ciliveri Jose D avila William Dernell Stuart B Goodman Susmita Bose W.M.Keck Biomedical Materials Research Laboratory School of Mechanical and Materials EngineeringWashington State UniversityPullmanWA 99164United States of America Veterinary Clinical Sciences College of Veterinary MedicineWashington State UniversityPullmanWA 99164United States of America Department of Orthopedic Surgery Stanford University Medical CenterRedwood CityCA 94063United States of America

Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limbs. In this study, laser powder bed fusion was implemented to fabricate Ti3Al2V alloy by a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed by the addition of Ta and Cu into the Ti3Al2V custom alloy. The biological,mechanical, and tribo-biocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance biocompatibility and impart inherent bacterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and Staphylococcus aureus strains of bacteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antibacterial efficacy, i.e.78%–86% with respect to CpTi. Mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved tribological and tribo-biocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed biocompatibility and no adverse infammatory response in vivo. Our results establish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving both in vivo biocompatibility and microbial resistance for the next generation of load-bearing metallic implants.

关键词： Ti6Al4V load-bearing implants additive manufacturing 3D printing antibacterial performance

Alzheimer’s visual variant: a report of a diagnosis easily missed on ophthalmic examination

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1571-1575页

作者： Jorge Cárdenas-Belaunzarán Lorena Wheelock-Gutierrez Karen A.Cerrillo-avila Department of Neuro-Ophthalmology Association to Prevent Blindness in MexicoI.A.P.Mexico City 04030Mexico Independent Researcher Mexico City 04040Mexico

Dear Editor,We present a case of posterior cortical atrophy(PCA),which is a syndromic entity caused by different neurodegenerative diseases,mainly Alzheimer’s disease,but it has been described in several other *** frequency is reported to be as high as 5%of all cases;however,it remains widely under-recognized among ophthalmologists and optometrists due to scarce reports in visual health-related journals[1].

关键词： diagnosis Alzheimer diseases

Assessing the impact of concurrent high-fructose and highsaturated fat diets on pediatric metabolic syndrome:A review

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World Journal of Clinical Pediatrics 2024年第2期13卷 62-79页

作者： Manuel Alejandro Vargas-Vargas Marcela González-Montoya Olin Torres-Isidro Claudia Isabel García-Berumen Omar Ortiz-avila Elizabeth Calderón-Cortés Christian Cortés-Rojo Instituto de Investigaciones Químico–Biológicas Universidad Michoacana de San Nicolás de HidalgoMorelia 58030MichoacánMexico Facultad de Enfermería Universidad Michoacana de San Nicolás de HidalgoMorelia 58020MichoacánMexico

High-saturated fat(HF)or high-fructose(HFr)consumption in children predispose them to metabolic syndrome(MetS).In rodent models of MetS,diets containing individually HF or HFr lead to a variable degree of ***,simultaneous intake of HF plus HFr have synergistic effects,worsening MetS *** children,the effects of HF or HFr intake usually have been addressed ***,we have reviewed the outcomes of HF or HFr diets in children,and we compare them with the effects reported in *** humans,HFr intake causes increased lipogenesis,hypertriglyceridemia,obesity and insulin *** the other hand,HF diets promote low grade-inflammation,obesity,insulin *** the deleterious effects of simultaneous HF plus HFr intake on MetS development in rodents,there is little information about the combined effects of HF plus HFr intake in *** aim of this review is to warn about this issue,as individually addressing the effects produced by HF or HFr may underestimate the severity of the outcomes of Western diet intake in the pediatric *** consider that this is an alarming issue that needs to be assessed,as the simultaneous intake of HF plus HFr is common on fast food menus.

关键词： Fructose Saturated fat Metabolic syndrome Insulin resistance Type 2 diabetes Ultra processed foods Children Obesity Dyslipidemia Non-alcoholic fatty liver disease

Traditional Use of Medicinal Plants Confirmed by the Baka in Southern and Eastern Cameroon

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Journal of Biosciences and Medicines 2024年第8期12卷 76-106页

作者： Natacha Nana Afiong Pascal Billong Fils Karelle Kouetchua Guekam Eloge Kambale Muhesi Eva avila Martin Guillermo Ros Brull Julia E. Fa Stephan Michael Funk Evariste Fongnzossie Fedoung Jean Lagarde Betti Department of Biology and Physiology of Plant Organisms University of Douala Douala Cameroon Zerca y lejos ONGD Madrid Spain Department of Natural Sciences School of Science and the Environment Manchester Metropolitan University Manchester UK Center for International Forestry Research (CIFOR) CIFOR Headquarters Bogor Indonesia Nature Heritage Jersey Channel Islands Manchester UK Laboratory of Forest Resources and Wood Valorization Training Unit in Engineering Sciences Post Graduate School of Fundamental and Applied Sciences University of Douala Douala Cameroun Department of Wood Sciences Higher Institute of Agriculture Wood Water resources and Environment University of Ber-toua Bertoua Cameroon

The limitations of biomedecine to provide effective solutions to certain pandemics has led many people to turn to alternative therapies. These palliative solutions, particularly phytomedecines, are much sought after for disease prevention and treatment. The Baka, a group of forest-dwelling people, hold knowledge on how wild plants can be effective in treating many illnesses. However, the greatest challenge for the identification of traditional medicines depends on the veracity of the information provided during ethnobotanic surveys by user populations. The present study describes forest plants used by the Baka and confirmed by them as being employed for traditional medicine. We carried out ethnobotanical surveys between 2019 and 2021 in 221 households within four districts of the Eastern and Southern Region of Cameroon. We used indices of significant use and performance applied to all mentioned species, alongside searches in the literature. The statistical tools used to distinguish the different groups/districts is Pearson’s X2 test. A total of 378 plant species were identified of 270 genera and 85 families. Ethnobotanical indices allowed to identify the most confirmed and efficient plants for several health problems. A pairwise comparison of these indices showed a significant correlation with a p-value < 2.2e-16 and a dissimilarity distance less than 0.5. Some plants selected are widely cited in other regions and/or countries for the same health problems. The presence of active molecules responsible for their biological activity was also proven, justifying their use in traditional medicine. This paper examines the potential to enhance the value of Cameroon’s pharmacopeia by integrating various ethnobotanical indices. It aims to discover new therapeutic molecules and develop improved traditional products from the diverse plant species documented. The findings indicate opportunities to advance both local and global healthcare solutions.

关键词： Confirmed Plants Import-Substitution Improved Traditional Medicine (ITM) Sustainable Development Goals Therapeutic Molecules

Perfect Single Qubit Mirroring Effects on Two and Three Maximally Entangled Qubits

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Communications in Theoretical Physics 2013年第1期59卷 7-10页

作者： M.avila Centro Universitario UAEM Valle de Chalco UAEMex Mar' a IsabelValle de ChalcoEstado de M'exicoCP 56615Mexico

Perfect quantum state mirroring in a chain of N spins is defined as the condition in which the state 丨i 丨of the chain is swapped into the state 丨N - i丨 within a time evolution interval r. Such a phenomenon is an interesting way of transfering entanglement. An expressions for the perfect mirroring of a single qubit contained in a spin chain were proposed in the past. We exploit such an expressions for calculating the evolution times in chains of both two and three spins. In the case of a chain of two qubits, we derive conditions under which the associated four Bell states diagonalize the Hamiltonian. It is found that for the two Bell states 丨Ф＋） and 丨Ф-）, perfect mirroring does not occur （i.e. entanglement is not preserved under swapping）. On the other hand, perfect single qubit mirror effect （entanglement preservation） indeed occurs for the other two Bell states 丨ψ＋） and 丨ψ-） which are mapped into 丨Ф＋） and 丨Ф-） respectively. For the case of a chain of three qubits, the effects of a perfect single qubit mirroring on a set of four maximally entangled three qubit states ψl, ψ2, X1, and X2are studied. Due to the fact that quantum mirroring preserves maximal entanglement, the states ψ1 and ψ2 are not altered. However, quantum mirroring changes the states X1 and X2 only if we apply perfect quantum state mirroring in the site a = 1 of the three qubits spin chain. The above constrains the preservation of maximal entanglement under qubit mirroring of such a state. Due to the fact that swapping has already been experimentally tested, a posible, experimental implementations of single qubit mirroring is possible.

关键词： time evolution of a state perfect quantum state mirroring of a single qubit Bell states Gisinstates quantum mirroring of Bell states quantum mirroring of Gisin states entanglement preset-vation

Biomimetic Control of Mechanical Systems Equipped with Musculotendon Actuators

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Journal of Bionic Engineering 2011年第1期8卷 56-68页

作者： Javicr Moreno-Valenzuel Adriana Salinas-avila Instituto Politecnico Naoional-CITEDl Av. del Parque 1310 Mesa de Otay Tianjuana B.C. 22510 Mexico

This paper addresses the problem of modelling, control, and simulation of a mechanical system actuated by an agonist-antagonist musculotendon subsystem. Contraction dynamics is given by case 1 of Zajac＇s model. Saturated semi positive proportional-derivative-type controllers with switching as neural excitation inputs are proposed. Stability theory of switched system and SOSTOOLS, which is a sum of squares optimization toolbox of Matlab, are used to determine the stability of the obtained closed-loop system. To corroborate the obtained theoretical results numerical simulations are carried out. As additional contribution, the discussed ideas are applied to the biomimetic control of a DC motor, i.e., the position control is addressed assuming the presence of musculotendon actuators. Real-experiments corroborate the expected results.

关键词： biomimetie control musculotendon dynamics neural excitation saturation switched systems

Management of hypertensive crises in the elderly

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Journal of Geriatric Cardiology 2018年第7期15卷 514-522页

作者： Abbas Alshami Carlos Romero America avila Joseph Varon Dorrington Medical Associates Houston Texas USA University of Baghdad/College of Medicine Baghdad Iraq Universidad Autonoma de San Luis Potosi San Luis Potosi Mexico Universidad Durango Santander Hermosillo Sonora Mexico The University of Texas Health Science Center at Houston USA The University of Texas Medical Branch at Galveston USA Critical Care Services United Memorial Medical Center / United General Hospital Houston Texas USA

Hypertensive crises are elevations of blood pressure higher than 180/120 mmHg. These can be urgent or emergent, depending on the presence of end organ damage. The clinical presentation of hypertensive crises is quite variable in elderly patients, and clinicians must be suspicious of non-specific symptoms. Managing hypertensive crises in elderly patients needs meticulous knowledge of the pathophysiological changes in them, pharmacological options, pharmacokinetics of the medications used, their side effects, and their interactions with other medications. Clevidipine, nicardipine, labetalol, esmolol, and fenoldopam are among the preferred choices in the elderly due to their efficacy and tolerability. Nitroprusside, hydralazine, and nifedipine should be avoided, unless there are no other options available, due to the high risk of complications and unpredictable responses.

关键词： Beta-blockers Calcium channel blockers Clevidipine Elderly Esmolol Fenoldopam Hypertensive crises Labetalol Nicardipine Nitroprusside

Quantum information entropies of the eigenstates for the Pschl-Teller-like potential

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Chinese Physics B 2013年第5期22卷 113-117页

作者： Guo-Hua Sun M. avila Aoki Shi-Hai Dong Centro Universitario Valle de Chalco Universidad Autónoma del Estado de México Departamento de Física Escuela Superior de Física y MatemáticsInstituto Politécnico Nacional

Shannon entropy for lower position and momentum eigenstates of Ptschl-Teller-like potential is evaluated. Based on the entropy densities demonstrated graphically, we note that the wave through of the position information entropy density p （x） moves right when the potential parameter V1 increases and its amplitude decreases. However, its wave through moves left with the increase in the potential parameter 丨V2丨. Concerning the momentum information entropy density p（p）, we observe that its amplitude increases with increasing potential parameter V1, but its amplitude decreases with increasing丨V2丨. The Bialynicki-Birula-Mycielski （BBM） inequality has also been tested for a number of states. Moreover, there exist eigenstates that exhibit squeezing in the momentum information entropy. Finally, we note that position information entropy increases with V1, but decreases with 丨V2丨, However, the variation of momentum information entropy is contrary to that of the position information entropy.

关键词： bound states quantum information entropy Poschl-Teller-like potential

Full Duplex Media Access Control Protocol for Multihop Network Computing

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Computer Systems Science & Engineering 2023年第1期44卷 297-309页

作者： J.avila Selvi Therase S.Allwin A.Ahilan Department of CSE Infant Jesus College EngineeringThoothukudiTamil Nadu628851India Department of ECE PSN College of Engineering and TechnologyMelathediyoorTamil Nadu627152India

Intelligent communication technologies beyond the network are pro-posed by using a new full-duplex *** Media Access Control(MAC)is a data interaction network protocol,which outperforms the IEEE *** research discusses the planning and execution of full-duplex(FD)pipeline MAC protocol for multihop wireless networks(MWN).The design uses a com-bination of Radio frequency and baseband methods to realize full-duplexing with smallest impact on cross layer *** execution and trial results specify that Pipeline Media Access Control(PiMAC)protocol considerably develops net-work implementation in terms of transmission protocol(TP)and transmission *** advantage of using FD-MAC will increase the range of *** takes benefit of the FD mode of the antenna,which outperforms additionally 80%for all assessed *** this analysis,it was considered of that Psz=8184 bits and Rc=1Mbps;that’s,T_(DATA) represents an excellent portion of total *** on real nodes displays that the FD theme achieves a median gain of 90%in mix-ture throughput as equated to half-duplex(HD)theme for *** energy con-sumption of proposed system method is 29.8%reduced when compared with existing system method.

关键词： Beyondfifth-generation(B5G) FD MAC wi-finetworks wireless relay network multihop wireless networks