Economics of payment cards: a status report

This article surveys the recent theoretical literature on payment cards (focusing on debit and credit cards) and studies this research's possible implications for the current public policy debate over payment card networks and the pricing of their services for both consumers and merchants.Payment systems ; Credit cards

Efeito do duplo envelhecimento nas propriedades da liga ti-12mo-13nb

Ligas de Ti do tipo β tem sido muito estudadas para aplicação em dispositivos biomédicos por apresentarem um balanço de vantagens em relação às outras ligas de Ti, tais como alta relação resistência / densidade, excelente resistência à fadiga e, além disso, tendem a apresentar o menor módulo dentre todos os tipos de ligas. Contudo, para um material ser utilizado como implante ortopédico é necessário um balanço entre alta resistência e baixo módulo de elasticidade. Estudos mostram que não é trivial obter simultaneamente baixo módulo de elasticidade e alta resistência nas ligas de Ti. Várias microestruturas podem ser obtidas por diferentes tratamentos de envelhecimento os quais influenciam várias propriedades das ligas e, portanto um satisfatório tratamento de envelhecimento poderá resultar num melhor balanço entre baixo módulo de elasticidade e alta resistência. Há vários tratamentos de envelhecimento que podem ser realizados em uma liga β metaestável. Um destes é o duplo envelhecimento, que consiste em dois processos. Realiza-se um envelhecimento em uma temperatura em torno de 250 ºC que favoreça a precipitação da fase ω (isotérmica) e um subsequente envelhecimento numa temperatura maior para a precipitação de fase α. O foco deste envelhecimento é obter uma precipitação de fase α mais fina e uniforme. Desta forma, o objetivo deste trabalho foi estudar o efeito do duplo envelhecimento nas propriedades da liga Ti-12Mo-13Nb. A liga Ti-12Mo-13Nb foi processada termomecanicamente e passou por um duplo envelhecimento que consistiu primeiramente num envelhecimento na temperatura de 300 ᵒC por 10 min, 45 min e 3 h e um subsequente envelhecimento na temperatura de 500 ºC por 24 h. Como resultado foi observado que não houve variação significativa na dureza e no módulo de elasticidade com a variação da fração volumétrica da fase ω durante o envelhecimento prévio da temperatura externa

HPV vaccination in Africa in the COVID-19 era: a cross-sectional survey of healthcare providers’ knowledge, training, and recommendation practices

IntroductionAlthough the burden of cervical cancer in Africa is highest, HPV vaccination coverage remains alarmingly low in this region. Providers’ knowledge and recommendation are key drivers of HPV vaccination uptake. Yet, evidence about providers’ knowledge and recommendation practices about the HPV vaccine against a backdrop of emerging vaccine hesitancy fueled by the COVID-19 pandemic is lacking in Africa.MethodsA cross-sectional study was conducted in 2021–2022 among healthcare providers involved in cervical cancer prevention activities in Africa. They were invited to report prior training, the availability of the HPV vaccine in their practice, whether they recommended the HPV vaccine, and, if not, the reasons for not recommending it. Their knowledge about the HPV vaccine was assessed through self-reporting (perceived knowledge) and with three pre-tested knowledge questions (measured knowledge).ResultsOf the 153 providers from 23 African countries who responded to the survey (mean age: 38.5 years, SD: 10.1), 75 (54.0%) were female and 97 (63.4%) were based In countries with national HPV immunization programs. Overall, 57 (43.8%) reported having received prior training on HPV vaccine education/counseling, and 40 (37.4%) indicated that the HPV vaccine was available at the facility where they work. Most respondents (109, 83.2%) reported recommending the HPV vaccine in their practice. Vaccine unavailability (57.1%), lack of effective communication tools and informational material (28.6%), and need for adequate training (28.6%) were the most commonly reported reasons for not recommending the HPV vaccine. While 63 providers (52.9%) reported that their knowledge about HPV vaccination was adequate for their practice, only 9.9% responded correctly to the 3 knowledge questions.ConclusionTo increase HPV vaccination coverage and counter misinformation about this vaccine in Africa, adequate training of providers and culturally appropriate educational materials are needed to improve their knowledge of the HPV vaccine and to facilitate effective communication with their patients and the community

Effect of magnesium addition on the mechanical properties of metallic composite materials based on the eutectic Al-5.7% Ni alloy

The effect of Mg addns. on the mech. properties of dispersion hardening alloys, prepd. from the eutectic Al-5.7% Ni by casting and isostatic extrusion was detd. A small amt. of Mg increases significantly the tensile strength and fracture elongation, and esp. stabilizes the alloy structure for annealing at high tempinfo:eu-repo/semantics/publishe

Synthesis and antibacterial activity of silver nanoparticles agains gram-positive and gram-negative bacteria

info:eu-repo/semantics/publishe

Effects of heat treatments on the ductility of cobalt electrodeposits

SCOPUS: ar.jinfo:eu-repo/semantics/publishe