Examination of gecko-inspired dry adhesives for heritage conservation as an example of iterative design and testing process for new adhesives

Rarely within the conservation of cultural heritage have conservation professionals been lucky enough to have materials custom-designed to meet their requirements. Most of the time the field must adapt solutions developed for other applications. The research presented here was initiated as part of a long-term aim to develop new adhesives for heritage conservation. Gecko-inspired dry adhesives (GDAs) are polymer tapes with micropatterns that are based on the adhesive properties of the pads of gecko lizard feet: they have strong normal and shear adhesion with low peel adhesion. They present potentially versatile and reversible adhesives for heritage conservation applications; which do not require solvents for activation or for removal, and do not migrate or off-gas. In nature, geckos can adhere with their feet to any surface they walk on. This is possible because of micro- and nanostructures on their feet that attach to surface via van der Waals forces. Practical studies aimed at comprehensively assessing their properties, and biomimetic solutions in heritage conservation are still sparse at present. This research has the objective of assessing GDAs properties by mechanical testing of adhesive joints, as well as physical and chemical characterisation of the materials used. The research has also included a museum case study and a two-year natural ageing test. The testing has shown that the GDAs can perform very well as an adhesive patch on the reverse of gelatine-based photographs, achieving shear forces between 0.80 N and 48.10 N on 8 cm2 lap joints (depending on the type of the GDA) and peel forces between 0.20 N and 0.47 N over 2 cm of peel front. This is lower than forces exceeding 1 N recorded in widely available pressure-sensitive tapes. This shows that GDAs may have the potential of a sufficiently strong, yet easily removable adhesive that works well on materials widely present in museum collections

A Not-So-Gentle Refutation of the Defence of Homeopathy

In a recent paper, Levy, Gadd, Kerridge, and Komesaroff attempt to defend the ethicality of homeopathy by attacking the utilitarian ethical framework as a basis for medical ethics and by introducing a distinction between evidence-based medicine and modern science. This paper demonstrates that their argumentation is not only insufficient to achieve that goal but also incorrect. Utilitarianism is not required to show that homeopathic practice is unethical; indeed, any normative basis of medical ethics will make it unethical, as a defence of homeopathic practice requires the rejection of modern natural sciences, which are an integral part of medical ethics systems. This paper also points out that evidence-based medicine lies at the very core of modern science. Particular arguments made by Levy et al. within the principlist medical ethics normative system are also shown to be wrong

Spontaniczne pęknięcie ściany lewej komory serca — prezentacja przypadku

Myocardial infarction is the most common reason left ventricle free wall rupture (LVFWR). Mechanical reperfusion in myocardial infarction has reduced almost twice the incidence of LVFWR as compared with the previous treatment. It should be remembered that LVFWR may be a complication of other cardiac conditions unrelated to myocardial infarction, such as endocarditis, myocarditis, primary or metastatic cardiac tumors, cardiotoxic effects of chemotherapy, infiltrative diseases, aortic dissection, Takotsubo cardiomyopathy, heart injuries and iatrogenic complications. A 64-year-old patient was admitted to the hospital after an episode of cardiac arrest in a mechanism of electrical activity without pulse, effectively resuscitated. In the ECG, there were features of ST-segment elevation myocardial infarction but coronary angiography did not show any significant lesions. Echocardiography revealed tamponade and rupture of the posterior wall with a simple transmyocardial channel covered by clot formed on the visceral pericardium. During transportation to the cardiac surgery ward catecholamines and intraaortic balloon counter-pulsation was applied. Dacron patch was used during cardiac surgery to close LVFWR. Secondary reasons of LVFWR have been excluded. The discussion has been focused on the symptoms, diagnosis and possible and preferred treatment of LVFWR in the cathlab.Zawał mięśnia sercowego stanowi najczęstszą przyczynę pęknięcia wolnej ściany lewej komory serca (LVFWR - left ventricle free wall rupture). Leczenie interwencyjne zawału serca pozwoliło na niemal dwukrotną redukcję częstości występowania LVFWR w porównaniu do poprzedniej ery terapii. Należy pamiętać, że LVFWR może stanowić powikłanie innych stanów kardiologicznych, niezwiązanych z pozawałową przebudową miokardium, takich jak: zapalenie wsierdzia/mięśnia sercowego, nowotwory pierwotne i przerzutowe serca, kardiotoksyczny wpływ chemioterapii, choroby naciekowe, rozwarstwienie aorty, kardiomiopatię Takotsubo, urazy serca oraz powikłania jatrogenne. Pacjentka lat 64 była przyjęta do szpitala po epizodzie zatrzymania krążenia w mechanizmie aktywności elektrycznej bez tętna ze skuteczną resuscytacją. W zapisie EKG stwierdzono cechy zawału ściany dolnej serca z uniesieniem odcinka ST. W koronarografii nie zobrazowano istotnych zmian zwężających. Badanie echokardiograficzne ujawniło tamponadę oraz cechy pęknięcia ściany tylnej serca z prostym kanałem oraz skrzepem na osierdziu trzewnym. Poza aminami katecholowymi w trakcie transportu do oddziału kardiochirurgii stosowano kontrapulsację wewnątrzaortalną. W trakcie operacji użyto łaty dakronowej dla zapewnienia ciągłości ściany. Wtórne przyczyny pęknięcia ściany zostały wykluczone. Dyskusja koncentruje się na objawach, diagnostyce oraz możliwym i preferowanym leczeniu LVFWR w pracowni hemodynamiki

Authenticating coins of the ‘Roman emperor’ Sponsian

The ‘Roman emperor’ Sponsian is known only from an assemblage of coins allegedly found in Transylvania (Romania) in 1713. They are very unlike regular Roman coins in style and manufacture, with various enigmatic features including bungled legends and historically mixed motifs, and have long been dismissed as poorly made forgeries. Here we present non-destructive imaging and spectroscopic results that show features indicative of authenticity. Deep micro-abrasion patterns suggest extensive circulation-wear. Superficial patches of soil minerals bound by authigenic cement and overlain by oxidation products indicate a history of prolonged burial then exhumation. These observations force a re-evaluation of Sponsian as a historical personage. Combining evidence from the coins with the historical record, we suggest he was most likely an army commander in the isolated Roman Province of Dacia during the military crisis of the 260s CE, and that his crudely manufactured coins supported a functioning monetary economy that persisted locally for an appreciable period

The effect of Propionibacterium acnes on maturation of dendritic cells derived from acne patients' peripherial blood mononuclear cells.

Propionibacterium acnes (P. acnes) has been implicated in the pathogenesis of acne vulgaris which is the most common cutaneous disorder. It has a proinflammatory activity and takes part in immune reactions modulating the Th1/Th2 cellular response. The exposure of dendritic cells (DCs) to whole bacteria, their components, cytokines or other inflammatory stimuli and infectious agents induces differentiation from immature DCs into antigen-presenting mature DCs. The aim of the study was to evaluate the capability of P. acnes to induce the maturation of DCs. We stimulated monocyte derived dendritic cells (Mo-DCs) from acne patients with various concetrations of heat-killed P. acnes (10(6)-10(8) bacteria/ml) cultured from acne lesions. The results showed an increase in CD80+/CD86+/DR+ and CD83+/CD1a+/DR+ cells percentage depending on the concetration of P. acnes. The expression of CD83 and CD80 (shown as the mean fluorescence intensity - MFI) increased with higher concetrations of P. acnes. There were also significant correlations between MFI of CD83, CD80, CD86 and concetration of P. acnes. The study showed that P. acnes in the concetration of 10(8) bacteria/ml is most effective in the induction of Mo-DCs maturation. Futher studies concerning the influence on the function of T cells are needed

Managed care after acute myocardial infarction (MC-AMI) reduces total mortality in 12-month follow-up : results from a Polands national health fund program of comprehensive post-MI care - a population-wide analysis

Introduction: Advances in the acute treatment of myocardial infarction (AMI) substantially reduced in-hospital mortality, but the post-discharge prognosis is still unacceptable. The Managed Care in Acute Myocardial Infarction (MC-AMI) is a program of Poland’s National Health Fund that aims at comprehensive post-AMI care to improve long-term prognosis. The aim of the study was to assess the effect of MC-AMI on all-cause mortality in one-year follow-up. Methods: MC-AMI includes acute MI treatment, complex revascularization, cardiac rehabilitation (CR), scheduled one-year outpatient follow-up, and prevention of sudden cardiac death. In this retrospective observational study performed in a province of Silesia, Poland, we analyzed 3893 MC-AMI participants, and compared them to 6946 patients in the control group. After propensity score matching, we compared two groups of 3551 subjects each. To assess the effect of MC-AMI and other variables on mortality, we preformed a Cox regression. Results: MC-AMI was related with mortality reduction by 38% in a 12-month observation period and the effect persisted even after. Multivariable Cox regression analysis revealed MC-AMI participation to be inversely associated with 1-year mortality (HR 0.52, 95%CI 0.42–0.65, p < 0.001). Besides that, older age (HR 1.47/10 y), ST-elevation AMI (HR 1.41), heart failure (HR 2.08), diabetes (HR 1.52), and dialysis (HR 2.38) were significantly associated with the primary endpoint. Among MC-AMI components, cardiac rehabilitation (HR 0.34) and strict outpatient care (HR 0.42) are the crucial factors affecting mortality reduction. Conclusions: Participation in MC-AMI reduced 1-year mortality by 38% and the effect persisted after the program had been completed