Degradation Performance of Open-Cell Biomaterials from Phosphated Carbonyl Iron Powder with PEG Coating

Advances in biomedicine and development of modern technologies in the last century have fostered the improvement in human longevity and well-being. This progress simultaneously initiated the need for novel biomaterials. Recently, degradable metallic biomaterials have attracted serious attention in scientific and clinical research owing to their utilization in some specific applications. This work investigates the effect of the polyethylene glycol (PEG) coating of open-cell iron and phosphorus/iron foams on their microstructure and corrosion properties. The addition of phosphorus causes a slight increase in pore size and the deposition of a polymer coating results in a smoothened surface and a moderate decrease in pore diameter. The PEG coating leads to an increase in corrosion rates in both foams and potentially a more desirable product.

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Cytocompatibility of Magnesium-Zinc-Calcium Alloys with Bone Marrow Derived Mesenchymal Stem Cells

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.922.1 ◽

2014 ◽

Vol 922 ◽

pp. 1-6

Author(s):

Aaron F. Cipriano ◽

Christopher Miller ◽

Hui Nan Liu

Keyword(s):

Biomedical Applications ◽

Culture Media ◽

Corrosion Properties ◽

Cell Culture Media ◽

Tissue Culture Polystyrene ◽

Metallic Biomaterials ◽

Zn Content ◽

Before And After ◽

Orthopedic Applications ◽

Early Indication

Magnesium (Mg)-based alloys have attracted great interest as metallic biomaterials for orthopedic applications due to their biocompatibility, biodegradability, and mechanical properties that resemble those of cortical bone. However, the potential toxicity of alloying elements in commercially available Mg alloys makes it critical to engineer and screen new alloys specifically for biomedical applications. The objective of this study was to evaluate and compare the in vitrodegradation and cytocompatibility of two distinct Mg - Zinc (Zn) - Calcium (Ca) alloys (Mg-4%Zn-1%Ca and Mg-9%Zn-1%Ca, wt. %; abbreviated as ZCa41 and ZCa91, respectively) using a bonemarrow derived mesenchymal stem cell (BMSC) model. Both Zn and Ca play critical roles in boneformation and growth, and have been shown to increase mechanical and corrosion properties of Mgalloys. BMSCs provide vertebrates the continuous supply of osteoblasts needed for bone remodelingand repair, and thus were selected to determine the effect of increasing Zn content on cell behavior.Surface microstructure and composition of the alloys were characterized before and after BMSC culture using field emission scanning electron microscopy (FESEM) and energy dispersive X-rayspectroscopy (EDS). Thermanox® treated glass and plasma treated tissue culture polystyrene were used as a control and reference, respectively. Results indicated that the ZCa91 alloy improved BMSC adhesion as compared with ZCa41 alloy. The formation of high-aspect ratio needle-likefeatures on the surface of ZCa41 alloy after its degradation in cell culture media was speculated tocontribute to the lower cell adhesion. This study provided an early indication on cytocompatibility of Mg-Zn-Ca alloys for biomedical applications.

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IS IT LONELY AT THE TOP? BIOPSYCHOSOCIAL VARIANTS OF LONELINESS AMONG CENTENARIANS

Innovation in Aging ◽

10.1093/geroni/igz038.148 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S38-S38

Author(s):

Alex J Bishop ◽

Oscar Riberio

Keyword(s):

Old Age ◽

Social Isolation ◽

Emotional Health ◽

Premature Death ◽

Well Being ◽

Health Impact ◽

Human Longevity ◽

Nutritional Health ◽

Very Old Age

Abstract There is a growing body of evidence supporting the detrimental impact of loneliness on biological, psychological, and social functioning. Loneliness has been cited to contribute to social isolation, mental health disorders, and premature death in old age. In turn, the prevention of loneliness has emerged as a priority area in geriatric and gerontology research, practice, and policy. However, determination of whether persons living 100 or more years feel lonely or socially disconnected has remained limited within centenarian research. Such research has historically fostered translation of insights and secrets for living long and aging well. Centenarians represent persons who have managed to survive, delay, or escape varying biopsychosocial losses that might otherwise deteriorate emotional health, exacerbate feelings of isolation, and limit human longevity potentials. Guided by a biopsychosocial framework, this symposium will consider biological, psychological, and social variants that contribute to risk as well as resilience in loneliness in very old age. Of particular interest is the advancement of evidence-based research exposing the interplay between loneliness and nutritional health, impact of lifelong childlessness on feelings of solitude, role of personality traits and the expression of loneliness, and the intersection between active religious engagement and loneliness. Biopsychosocial attributes that reduce the threat of social isolation and loneliness, as well as improve emotional well-being in human longevity will be further discussed. Implications relevant for geriatric counseling and wellness programming for old-old adults will be highlighted.

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Digitalization opportunities for the procurement function: pathways to maturity

International Journal of Operations & Production Management ◽

10.1108/ijopm-04-2020-0214 ◽

2020 ◽

Vol 40 (11) ◽

pp. 1685-1693

Author(s):

Zahra Seyedghorban ◽

Danny Samson ◽

Hossein Tahernejad

Keyword(s):

Supply Chain ◽

Well Being ◽

Supply Chain Design ◽

Strategic Partner ◽

Content Type ◽

Study Approach ◽

Modern Technologies ◽

Initial Research

PurposeThis research aims at investigating the common practical problem of how procurement can be transformed from tactical and administrative to becoming an organizational strategic partner and indeed a competitive weapon, using modern technologies in particular. We investigated how procurement can be reinvented, from being digitized to digitalized to digitally integrated, ultimately contributing in business terms beyond supply chain effectiveness but also to profit generation.Design/methodology/approachA case study approach was designed to investigate three firms, each at very different stages of digital maturity in procurement. Interviews with managers, investigation of processes and documentary materials and in-depth follow-up discussions were conducted.FindingsThe iterative digitalization transformation discovered encompasses complexities rooted in organizational structure, supply chain design and the management of the technology for employees' uptake. There are both operations and strategy implications as a result. This initial research phase led to mapping a model of digital maturity as well as identifying its underlying constructs.Originality/valueThis research discovered that the implementation of digital technologies can lead the procurement function of the supply chain to completely grow out of its administrative and clerical shell into a strategic, consultative, value-adding and potentially revenue-generating function, thereby contributing to the well-being of not only the supply chain but also the entire organization.

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Corrosion Properties of 20# Pipelines Steel in Near-Neutral Soils

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.129-131.312 ◽

2010 ◽

Vol 129-131 ◽

pp. 312-316

Author(s):

Wen He Wang ◽

Jun Yi ◽

Shi Ming Shen

Keyword(s):

Open Circuit Potential ◽

Low Carbon Steel ◽

Open Circuit ◽

Corrosion Mechanism ◽

Low Carbon ◽

Corrosion Properties ◽

Corrosion Rates ◽

Cathode Area ◽

Neutral Soil ◽

Anode Area

Corrosion law and mechanism of 20# low-carbon steel in near-neutral soil along Yangtze River in Nanjing are studied by experiments of buried specimens in laboratory. In three kinds of soils, the corrosion features and products are analyzed by EDS and XRD, and the relation of corrosion rates, open-circuit potential and polarization curve with times are tested. The results indicated that corrosion rates changed incessantly along. On the condition of the same times, specimens and different soil samples, the corrosive degree of 1# and 2# specimens are serious, but 3# specimen is serious lightly. The corrosion products are main non-crystalloid, Fe (OH) 3 and Fe2O3.The changing tendency of different times and soils is different, and accordant with that of corrosion rates. The corrosion mechanism is discussed lastly, in near-neutral soils, oxygen is deoxidized and OH- ions are created in cathode area, iron is oxidized and the hydration of Fe2+ ions is created with water from soil in anode area, and Fe2+ are converted into more steady products Fe（OH）3 and Fe2O3.

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Experimental and numerical investigation on the effective thermal conductivity of stochastic structure

Materials Express ◽

10.1166/mex.2019.1566 ◽

2019 ◽

Vol 9 (8) ◽

pp. 861-871

Author(s):

Milad Saljooghi ◽

Younes Bakhshan ◽

Saeid Niazi ◽

Jamshid Khorshidi

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Effective Thermal Conductivity ◽

Metal Foam ◽

Metal Foams ◽

Open Cell ◽

Geometrical Properties ◽

Copper Aluminum ◽

Thermo Physical Properties ◽

Modern Technologies

The Conception of thermo-physical properties of porous materials is a challenging task for scientists to conquer. The open cell metal foam increases heat transfer while energy dissipation, dimension and density of them which are constraints for modern technologies significantly reduce. In the present study, the open cell metal foams with four kinds of structures have been investigated numerically and experimentally and the effective thermal conductivity (ETC) of them have been extracted with using different base fluids such as water, air and paraffin. Also, various metals have been considered copper, aluminum, nickel and silver. Finally, a validated correlation for calculation of ETC of open cell metal foams has been developed which is function of thermal conductivity of fluid and metal, porosity and geometrical properties of pore that is applicable for all open cell metal foam approximately. The results show, good agreements between the modeling results and experimental data.

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Patient orientation is the main focus of the general practitioner’s work

Spravočnik vrača obŝej praktiki (Journal of Family Medicine) ◽

10.33920/med-10-2104-02 ◽

2021 ◽

pp. 15-20

Author(s):

Oksana Aleksandrovna Rybachok

Keyword(s):

Health Care ◽

Well Being ◽

Individual Characteristics ◽

Economic Conditions ◽

Patient Organizations ◽

Modern Economic ◽

The Russian Federation ◽

The Individual ◽

Second World ◽

Modern Technologies

Taking into account the uneven settlement of the population of the Russian Federation, as well as with the aim of adapting the medical sphere to modern economic conditions in the context of the new economic mechanism, the reform of the health care system was started in the late 1990s. As a result of the reorganization of the primary care, a new specialty appeared, i.e. general practitioners, who replaced therapists and pediatricians. For many years, the principle of treatment of the disease was dominant in the Russian health care, without taking into account the individual characteristics of a patient; the introduced reform was aimed at ensuring that the doctor would advise a particular patient for all his/her life, know the characteristics of the organism, and understand the etiopathogenesis of the development of a particular disease. In February 2006, at the second World Patient Congress held in Spain by the International Alliance of Patient Organizations (IAPO), the Declaration on Patient-Centred Healthcare was adopted. It is an alternative program, aimed primarily not at treatment, but at the prevention of diseases, health promotion and the formation of general well-being, based on modern technologies and an individual approach to each patient.

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Surface Modification of Magnesium with Rare Earth Conversion Films for Biomedical Protection

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.601 ◽

2007 ◽

Vol 546-549 ◽

pp. 601-604 ◽

Cited By ~ 2

Author(s):

Jia Cheng Gao ◽

Yan Xue ◽

Li Ying Qiao ◽

Yong Wang ◽

Yan Zhang

Keyword(s):

Corrosion Resistance ◽

Rare Earth ◽

Metabolic Process ◽

The Body ◽

Surface Microstructure ◽

Corrosion Properties ◽

Corrosion Rates ◽

Protective Films ◽

Relationship Of ◽

The Relationship

The specific gravity and elastic modulus of magnesium alloys are similar to that of human bone. Magnesium is one of the most important elements in the human body and plays a key role in the metabolic process. But the application of magnesium is seriously limited as a biomaterial since it corrodes easily in the physiological environment of the body. In order to reduce the corrosion, we developed protective films using rare earth (RE) conversion processing. The surface of magnesium samples was modified by contact with different rare-earth salt solutions; then the samples were dipped in SBF to test their corrosion resistance. The change of mass and the pH of the solutions were measured continuously using an electronic scale and a pH micrometer. The surface microstructure of the samples was observed by XRD and metallomicroscope. Corrosion rates of the samples in SBF were determined using Taffier curve. The preliminary results show that the conversion treatment with CeCl3 or Y(NO3)3 can improve the corrosion resistance of magnesium in SBF. The relationship of the RE salts concentration and the corrosion properties were studied,the best combination of parameters was determined, and the formation mechanism of rare-earth conversion film has been also elaborated.

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An In Vitro Corrosion Study of Open Cell Iron Structures with PEG Coating for Bone Replacement Applications

Metals ◽

10.3390/met8070499 ◽

2018 ◽

Vol 8 (7) ◽

pp. 499 ◽

Cited By ~ 9

Author(s):

Lucia Haverová ◽

Renáta Oriňaková ◽

Andrej Oriňak ◽

Radka Gorejová ◽

Matej Baláž ◽

...

Keyword(s):

Open Cell ◽

Corrosion Study ◽

Bone Replacement ◽

Peg Coating

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Effects of pH and Elevated Glucose Levels on the Electrochemical Behavior of Dental Implants

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-11-00083 ◽

2014 ◽

Vol 40 (2) ◽

pp. 153-159 ◽

Cited By ~ 6

Author(s):

Evsen Tamam ◽

Ilser Turkyilmaz

Keyword(s):

Dental Implants ◽

Electrochemical Impedance ◽

Electrochemical Corrosion ◽

Physiological Solution ◽

Titanium Implants ◽

Corrosion Properties ◽

Cyclic Polarization ◽

High Blood Glucose ◽

Glucose Levels ◽

Corrosion Rates

Implant failure is more likely to occur in persons with medically compromising systemic conditions, such as diabetes related to high blood glucose levels and inflammatory diseases related to pH levels lower than those in healthy people. The aim of this study was to investigate the effects of lower pH level and simulated- hyperglycemia on implant corrosion as these effects are critical to biocompatibility and osseointegration. The electrochemical corrosion properties of titanium implants were studied in four different solutions: Ringer's physiological solution at pH = 7.0 and pH = 5.5 and Ringer's physiological solution containing 15 mM dextrose at pH = 7 and pH = 5.5. Corrosion behaviors of dental implants were determined by cyclic polarization test and electrochemical impedance spectroscopy. Surface alterations were studied using a scanning electron microscope. All test electrolytes led to apparent differences in corrosion behavior of the implants. The implants under conditions of test exhibited statistically significant increases in Icorr from 0.2372 to 1.007 μAcm−2, corrosion rates from 1.904 to 8.085 mpy, and a decrease in polarization resistances from 304 to 74 Ω. Implants in dextrose-containing solutions were more prone to corrosion than those in Ringer's solutions alone. Increasing the acidity also yielded greater corrosion rates for the dextrose-containing solutions and the solutions without dextrose.

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