MODELING OF CLOSE-CONTACT AND CONVECTIVE MELTING IN AN AXISYMMETRIC CYLINDRICAL GEOMETRY

Author(s):  
Tomer Shockner ◽  
Gennady Ziskind
Author(s):  
Z. Hruban ◽  
J. R. Esterly ◽  
G. Dawson ◽  
A. O. Stein

Samples of a surgical liver biopsy from a patient with lactosyl ceramidosis were fixed in paraformaldehyde and postfixed in osmium tetroxide. Hepatocytes (Figs. 1, 2) contained 0.4 to 2.1 μ inclusions (LCI) limited by a single membrane containing lucid matrix and short segments of curved, lamellated and circular membranous material (Fig. 3). Numerous LCI in large connective tissue cells were up to 11 μ in diameter (Fig. 2). Heterogeneous dense bodies (“lysosomes”) were few and irregularly distributed. Rough cisternae were dilated and contained smooth vesicles and surface invaginations. Close contact with mitochondria was rare. Stacks were small and rare. Vesicular rough reticulum and glycogen rosettes were abundant. Smooth vesicular reticulum was moderately abundant. Mitochondria were round with few cristae and rare matrical granules. Golgi complex was seen rarely (Fig. 1). Microbodies with marginal plates were usual. Multivesicular bodies were very rare. Neutral lipid was rare. Nucleoli were small and perichromatin granules were large. Small bile canaliculi had few microvilli (Fig. 1).


Author(s):  
Kenneth S. Vecchio

Shock-induced reactions (or shock synthesis) have been studied since the 1960’s but are still poorly understood, partly due to the fact that the reaction kinetics are very fast making experimental analysis of the reaction difficult. Shock synthesis is closely related to combustion synthesis, and occurs in the same systems that undergo exothermic gasless combustion reactions. The thermite reaction (Fe2O3 + 2Al -> 2Fe + Al2O3) is prototypical of this class of reactions. The effects of shock-wave passage through porous (powder) materials are complex, because intense and non-uniform plastic deformation is coupled with the shock-wave effects. Thus, the particle interiors experience primarily the effects of shock waves, while the surfaces undergo intense plastic deformation which can often result in interfacial melting. Shock synthesis of compounds from powders is triggered by the extraordinarily high energy deposition rate at the surfaces of the powders, forcing them in close contact, activating them by introducing defects, and heating them close to or even above their melting temperatures.


1994 ◽  
Vol 07 (04) ◽  
pp. 180-182
Author(s):  
N. Gofton ◽  
Joanne Cockshutt

The AO wire passer can be used as an effective guide for passage of obstetrical saw wire for osteotomy. Use of the wire saw and passer reduces soft tissue trauma by minimizing tissue dissection, and promoting positioning of the saw in close contact with the bone.


1987 ◽  
Vol 58 (02) ◽  
pp. 786-789 ◽  
Author(s):  
O Behnke

SummaryAdhesion of rat blood platelets to native rat tail collagen fibrils was studied in the electron microscope under conditions that preserved collagen-associated proteoglycans (CAPG). The CAPG molecules were aligned in chain-like configurations that encircled the fibrils with a 65 nm period; they appeared to coat the fibrils completely and extended 60-100 nm away from the fibril. The initial platelet-fibril contact occurred between the platelet glycocalyx and the CAPG of the fibrils i.e. between two surfaces with net-negative charges. When close contact was established between the fibril surface proper and the platelet membrane, CAPG were not identified in the area of contact, and the collagen-platelet distance was reduced to a ~10-12 nm wide gap traversed by delicate links in register with fibril periodicities.


2020 ◽  
Vol 33 (1) ◽  
pp. 41-47
Author(s):  
Mohsena Akhter ◽  
Ishrat Bhuiyan ◽  
Zulfiqer Hossain Khan ◽  
Mahfuza Akhter ◽  
Gulam Kazem Ali Ahmad ◽  
...  

Background: Scabies is one of the most common skin diseases in our country. It is caused by the mite Sarcoptes scabiei var hominis, which is an ecto-parasite infesting the epidermis. Scabies is highly contagious. Prevalence is high in congested or densely populated areas. Individuals with close contact with an affected person should be treated with scabicidal which is available in both oral and topical formulations. The only oral but highly effective scabicidal known to date is Ivermectin. Amongst topical preparations, Permethrin 5 % cream is the treatment of choice. Objective: To evaluate the efficacy & safety of oral Ivermectin compared to topical Permethrin in the treatment of scabies. Methodology: This prospective, non-randomized study was conducted at the out-patient department of Dermatology and Venereology of Shaheed Suhrawardy Medical College & Hospital over a period of 6 months, from August 2016 to January 2017. The study population consisted of one hundred patients having scabies, enrolled according to inclusion criteria. They were divided into two groups. group A was subjected to oral Ivermectin and the group B to Permethrin 5% cream. Patients were followed up on day 7 and 14 for assessment of efficacy and safety. Result: The mean scoring with SD in group A (Ivermectin) and group B (Permethrin) were 8.26 ± 2.22 and 7.59 ± 2.01 respectively at the time of observation. The difference between the mean score of the two group is not significant (p=0.117) the mean scoring with SD in group A and group B were 4.54 ± 2.05 and 1.64 ± 1.84 respectively at 7thdays. The difference between the mean score of the two group is significant (p<0.001). The mean scoring with SD in group A and group B were 2.68± 2.35 and .36± 1.10 respectively at 14th day difference between the mean score of the group is significant (p<0.001). Conclusion: Topical application of permethrin 5% cream is more effective and safer than oral Ivermectin in the treatment of scabies. TAJ 2020; 33(1): 41-47


2020 ◽  
Vol 99 (10) ◽  

Besides the conventional extracorporeal circulation, commonly used in cardiac surgery, the methods of extracorporeal life support (ECLS) have been applied ever more frequently in thoracic surgery in recent years. The most commonly used modalities of such supports include extracorporeal membrane oxygenation (ECMO) and the Novalung interventional lung assist device (iLA). Successful application of ECLS has led to its more frequent use in general thoracic surgery, especially as a tool to treat hypercapnia and to ensure oxygenation and haemodynamic support. However, these methods are essential in lung transplant programmes; without their help, in most cases, it would not be possible to perform the transplantatioz or prevent the severe complications associated with critical primary graft dysfunction. Additionally, the extracorporeal circulation also facilitates the performing of specific surgical procedures that would not be feasible under standard conditions or would be associated with an inadequate risk. The application of extracorporeal life supports can fundamentally increase the level of resection when treating advanced intrathoracic malignancies that are in close contact with the heart and large vessels or even directly extend into them. Without the possibility of resecting such structures en bloc, together with the tumour, and, thus, achieving an R0 resection, these malignant tumours are often directly contraindicated for surgery or are operated non-radically, i.e. unsuccessfully. Complete tumour resection is the most important prognostic factor in the surgery.


Author(s):  
Robson de Lima GOMES ◽  
Marlus da Silva PEDROSA ◽  
Claudio Heliomar Vicente da SILVA

ABSTRACT Since the outbreak of the Coronavirus Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), numerous restrictive measures have been adopted by governments of different countries. The return to elective dental care in Brazil is a reality even during the COVID-19 pandemic. During restorative dental procedures, the dental professional requires close contact with the patient, being exposed to contaminated saliva and fluids. In addition, transmission of COVID-19 by the generation of aerosol produced by dental handipieces may be possible. Thus, the dental staff must know how to act during restorative dental procedures, putting into practice the correct clinical protocols to avoid cross-contamination and COVID-19 spread. The purpose of this article is to review the literature on the biosafety practices especially in the context of restorative dental procedures in times of COVID-19.


2020 ◽  
Vol 12 (45) ◽  
pp. 63-66
Author(s):  
Halim Nagem Filho ◽  
Reinaldo Francisco Maia ◽  
Reinaldo Missaka ◽  
Nasser Hussein Fares

The osseointegration is the stable and functional union between the bone and a titanium surface. A new bone can be found on the surface of the implant about 1 week after its installation; the bone remodeling begins between 6 and 12 weeks and continues throughout life. After the implant insertion, depending on the energy of the surface, the plasma fluid immediately adheres, in close contact with the surface, promoting the adsorption of proteins and inducing the indirect interaction of the cells with the material. Macrophages are cells found in the tissues and originated from bone marrow monocytes. The M1 macrophages orchestrate the phagocytic phase in the inflammatory region and also produce inflammatory cytokines involved with the chronic inflammation and the cleaning of the wound and damaged tissues from bacteria. On the other hand, alternative-activated macrophages (M2) are activated by IL-10, the immune complex. Its main function consists on regulating negatively the inflammation through the secretion of the immunosuppressant IL-10. The M2 macrophages present involvement with the immunosuppression, besides having a low capacity for presenting antigens and high production of cytokines; these can be further divided into M2a, M2b, and M2c, based on the gene expression profile.


Sign in / Sign up

Export Citation Format

Share Document