Comparison of mechanical properties of different types of gypsum applied in dentistry

2018 ◽  
Vol 68 (3) ◽  
pp. 302-308
Author(s):  
Magda Krasińska-Mazur ◽  
Wojciech Ryniewicz ◽  
Joanna Ryniewicz ◽  
Jolanta E. Loster
Keyword(s):  
Mechanical Properties ◽  
Rapid Development ◽  
Plaster Cast ◽  
Two Dimensions ◽  
Compression Tests ◽  
Different Types ◽  
Digital Scanning ◽  
Almost All ◽  
Type 3

Regardless of the rapid development of various digital scanning techniques of oral tissues, gypsum remains the most widespread material used in the laboratory execution of almost all prosthetic restorations. The mechanical properties of different types of gypsum are affected by the amount and temperature of the water used to preparing the mass, as well as the method and speed of its mixing. The aim of the study was to compare the mechanical properties of type 2, 3 and 4 gypsum during crushing and breaking tests, depending on the way of preparing the mass. Material and methods. For each test, 60 plaster samples in the shape of a cylinder were prepared in two dimensions: 4x10 mm and 4x20 mm. The material used to make the samples were Stodent II (type 2) and Stodent III (type 3) from Zhermapol and Fuji Rock from GC (type 4). Gypsum was mixed by hand or by vacuum machine. Six groups of samples of 10 were obtained. After 1 week, when the samples were stored at room temperature, they were subjected to crushing and breaking tests on the INSTRON 3345 strength machine. Results. The results of compression tests and three-point fracture were analyzed statistically using the Statistica 13.1 software (StatSoft). The greatest strength both crushing and breaking showed samples of type 4 gypsum, the smallest - type 2 plaster cast. Significantly lower standard deviation was observed in the case of mixed gypsum with the use of a vacuum mixer. Conclusion. Gypsum models should be cast from vacuum mixed gypsum.

FUNCTIONAL STATUS AND ADAPTIVE POTENTIAL IN FOREIGN STUDENTS WITH DIFFERENT TYPES OF VEGETATIVE REGULATION DURING TUITION

2020 ◽  
pp. 118-126
Author(s):  
A.M. Satarkulova
Keyword(s):  
Heart Rate ◽  
Foreign Students ◽  
Autonomic Regulation ◽  
The Body ◽  
Functional Changes ◽  
Different Types ◽  
Type 3 ◽  
Adaptive Abilities

The assessment and dynamic control over students’ status is a very important task. It allows timely detection of prenosological status prior to pathology and health maintenance in students. The objective of the paper is to assess the adaptive abilities of the body, to analyze changes in heart rate variability indicators in students with various types of autonomic regulation, to identify prenosological status and precursory pathological symptoms. Materials and Methods. The study enrolled 302 students from India, aged 21.54±1.43. Programming complex «Psychophysiologist» was used to register the main HRV parameters within 5 minutes. Health status was evaluated according to the index of functional changes and the scale of functional states. Results. N.I. Shlyk (2009) distinguished two groups of students with different types of autonomic regulation: type 1 (53 %) with moderate and type 2 (5 %) with marked characteristics of central regulation profile, type 3 (35 %) with moderate and type 4 (7 %) with marked characteristics of autonomous regulation profile. Main parameters of HRV and adaptation potential were defined for each student.All the parameters characterized functional and health status. Conclusions. It was shown that 82 % of trial subjects (type 1), 53 % (type 2), 94 % (type 3) and 95 % (type 4) demonstrated satisfactory adaptation and their physiological processes were at an optimal level. 18 % of students (type 1) demonstrated reduced adaptive abilities of the body. Moreover, they were under moderate stress. 47 % of subjects (type 2) were also under a significant stress, which was proven by excessively high SI, low SDNN and TP, and an increased index of functional changes. 5 % of students (type 4) revealed dysfunctional characteristics in the heart rhythm, peculiar to pathology. Keywords: foreign students, heart rate variability, types of autonomic regulation, adaptation potential, functional status. Оценка состояния студентов и динамический контроль за ним является важной задачей, поскольку позволяет своевременно выявлять у студентов донозологические состояния, предшествующие патологии, и способствовать сохранению здоровья. Цель. Оценка адаптивных возможностей организма, анализ изменений показателей вариабельности сердечного ритма у студентов с различными типами вегетативной регуляции, выявление донозологических состояний и ранних признаков патологии. Материалы и методы. В исследовании участвовало 302 студента в возрасте 21,54+1,43 года из Индии. Регистрировались основные параметры ВСР в течение 5 мин с использованием программно-аппаратного комплекса «Психофизиолог». Состояние и уровень здоровья оценивались по индексу функциональных изменений и шкале функциональных состояний. Результаты. По способу, предложенному Н.И. Шлык, выделены группы студентов с различными типами вегетативной регуляции: I (53 %) и II типы (5 %) – с умеренным и выраженным преобладанием центрального контура регуляции соответственно, III (35 %) и IV типы (7 %) – с умеренным и выраженным преобладанием автономного контура регуляции соответственно. У каждого из студентов определены основные параметры ВСР и адаптационного потенциала, характеризующие функциональное состояние и уровень здоровья. Выводы. Показано, что для 82 % обследуемых с I типом, 53 % со II типом, 94 % c III типом и 95 % с IV типом регуляции характерно состояние удовлетворительной адаптации, физиологические процессы сохраняются на оптимальном уровне. В группе студентов I типа у 18 % студентов адаптивные возможности организма снижены, выявлено состояние умеренного напряжения. У 47 % обследуемых II типа также зафиксировано состояние резко выраженного напряжения, индикатором которого является чрезмерно высокое значение SI, низкие величины SDNN и ТP, повышенное значение индекса функциональных изменений. В группе студентов с IV типом у 5 % учащихсяв регуляции ритма сердца выявлены дисфункциональные признаки, характерные для патологии. Ключевые слова: иностранные студенты, вариабельность сердечного ритма, типы вегетативной регуляции, адаптационный потенциал, функциональное состояние.

scholarly journals Molecular and Mechanobiological Pathways Related to the Physiopathology of FPLD2

Cells ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1947
Author(s):  
Alice-Anaïs Varlet ◽  
Emmanuèle Helfer ◽  
Catherine Badens
Keyword(s):  
Mechanical Properties ◽  
Signaling Pathways ◽  
Metabolic Disorders ◽  
Lamin A ◽  
Partial Lipodystrophy ◽  
Familial Partial Lipodystrophy ◽  
Atherosclerotic Cardiovascular Diseases ◽  
Almost All ◽  
Type V

Laminopathies are rare and heterogeneous diseases affecting one to almost all tissues, as in Progeria, and sharing certain features such as metabolic disorders and a predisposition to atherosclerotic cardiovascular diseases. These two features are the main characteristics of the adipose tissue-specific laminopathy called familial partial lipodystrophy type 2 (FPLD2). The only gene that is involved in FPLD2 physiopathology is the LMNA gene, with at least 20 mutations that are considered pathogenic. LMNA encodes the type V intermediate filament lamin A/C, which is incorporated into the lamina meshwork lining the inner membrane of the nuclear envelope. Lamin A/C is involved in the regulation of cellular mechanical properties through the control of nuclear rigidity and deformability, gene modulation and chromatin organization. While recent studies have described new potential signaling pathways dependent on lamin A/C and associated with FPLD2 physiopathology, the whole picture of how the syndrome develops remains unknown. In this review, we summarize the signaling pathways involving lamin A/C that are associated with the progression of FPLD2. We also explore the links between alterations of the cellular mechanical properties and FPLD2 physiopathology. Finally, we introduce potential tools based on the exploration of cellular mechanical properties that could be redirected for FPLD2 diagnosis.

New Concept: Different Types of Insufficiency of the Saphenofemoral Junction Identified by Duplex as a Chance for a More Differentiated Therapy of the Great Saphenous Vein

2013 ◽  
Vol 28 (5) ◽  
pp. 268-274 ◽  
Author(s):  
M Stücker ◽  
R Moritz ◽  
P Altmeyer ◽  
S Reich-Schupke
Keyword(s):  
Clinical Practice ◽  
Saphenous Vein ◽  
Great Saphenous Vein ◽  
Effective Therapy ◽  
Optimal Therapy ◽  
Different Types ◽  
Type 3 ◽  
Saphenofemoral Junction

Even though the item ‘saphenofemoral junction’ (SFJ) is anatomically well defined, the incontinence of the SFJ is often incompetently described in clinical practice and studies. Especially with regard to the optimal therapy of the great saphenous vein, it might be of importance to have a more distinct regard to the SFJ as it is known that about 10–30% of the saphenous refluxes have no femoral origin. Considering the terminal and preterminal valve three types of incompetence of the SFJ may be differentiated: Type 1: Incompetent terminal, but competent preterminal valve; Type 2: Competent terminal, but incompetent preterminal valve; Type 3: Incompetent terminal and preterminal valve (complete incompetence). A review on prior studies and reports leads to the assumption that the differentiation of the distinct types of SFJ-incompetence allows a more individual and – perhaps – more effective therapy. Finally, studies are necessary to evaluate the here given new concept.

New insights into the magmatic system southeast of El Hierro from high-resolution 2D seismic data

2020 ◽  
Author(s):  
Kai-Frederik Lenz ◽  
Felix Gross ◽  
Andreas Klügel ◽  
Rachel Barrett ◽  
Philipp Held ◽  
...  
Keyword(s):  
High Resolution ◽  
Canary Islands ◽  
Magmatic Activity ◽  
Magmatic System ◽  
El Hierro ◽  
Specific Distribution ◽  
Different Types ◽  
Type 3

<p>A new high-resolution seismic dataset is used to investigate the distribution and influence of different phases of magmatic activity in the southeast of El Hierro, Canary Islands. The Canary Archipelago off NW-Africa has largely been formed over the past 20 Myr, but older volcanic edifices exist. One of those older edifices is Henry Seamount, an extinct 126 Ma volcano located 40 km southeast of El Hierro, the youngest (1.1 Ma) and westernmost of the Canary Islands. Hence, the area southeast of El Hierro is influenced by both older and younger magmatic activity. We also found evidence for comparatively young volcanic activity at Henry Seamount, probably contemporaneous to El Hierro. Therefore, a complex magmatic system is assumed to have resulted in the different phases of magmatic activity.</p><p>A detailed high-resolution 2D seismic reflection dataset was collected in an area between El Hierro and Henry Seamount during RV Meteor expedition M146 in 2018 to image the expressions of this magmatic system in the upper sub-surface. Several acoustic blanking zones were discovered and identified as the most prominent features in this seismic dataset. We classify these blanking zones into three different types. Type 1 blanking zones are related to volcanic edifices, which crop out at the seafloor and cut through all imaged sedimentary units. Type 2 blanking zones are characterised by upward bending of adjacent reflectors and are most likely caused by hydrothermal doming resulting from saucer-shaped sill intrusions. Type 3 blanking zones cut clearly through adjacent reflectors, and are probably related to fluids or gases that were mobilized by the sill intrusions. The type 1 and 2 blanking zones cluster in the central part of the working area, whereas the blanking zones of type 3 are located on the outskirts. This specific distribution and the occurrence of the varying blanking zone types are combined to make a conceptual model of this complex magmatic system. Our model takes sill intrusions, hydrothermal doming, as well as volcanic out-crops and mobilized fluids into account. Therefore, this study provides new insights into the magmatic evolution of the youngest Canary Island, which can help to achieve a better understanding of the whole system.</p>

Orthotic variations in the management of infantile tibia vara and the results of treatment

2013 ◽  
Vol 37 (5) ◽  
pp. 375-383 ◽  
Author(s):  
Serap Alsancak ◽  
Senem Guner ◽  
Hakan Kinik
Keyword(s):  
Successful Outcome ◽  
Foot Orthoses ◽  
Full Time ◽  
Duration Of Treatment ◽  
Tibia Vara ◽  
Ankle Foot Orthoses ◽  
Different Types ◽  
Type 3

Background:Infantile tibia vara is an acquired form of tibial deformity associated with tibial varus and internal torsion. Several methods have been described for orthotics treatment. The purpose of this study was to determine the effectiveness of orthotics treatment in infantile tibia vara.Study design:Controlled trial.Objective:The aim of this study was to compare the effect of different types of orthoses and correction methods on decreasing the curve in children with severe genu varum.Methods:Three different types of knee–ankle–foot orthoses were applied to 35 lower extremities of 22 pediatric participants who were 19–38 months of age. The same orthotic design principles were used to correct the femur, while different designs were applied to correct the tibia. The orthoses used on 20 participants were evaluated for differences among them and their effects on the treatment process. In addition, methods used in the treatment, problems encountered, production of different types of orthoses, convenience of application of the orthoses, and degree of patients satisfaction are discussed in this article.Results:The mean duration of treatment of the participants until completion of treatment was 25.3 ± 9.7 weeks with a minimum of 9 weeks and a maximum of 41 weeks. No statistically significant correlation was found between the duration of orthotic use in patients with a successful outcome and percentile height and percentile weight. When the duration of treatment using the different types of orthoses was analyzed, significant differences were found between Type 1 and Type 2, and Type 1 and Type 3 orthoses (p < 0.05), while no difference was observed between Type 2 and Type 3 orthoses (p > 0.05).Conclusion:We found that bracing is an effective form of treatment for infantile tibia vara up to 38 months of age. We conclude that full-time use of knee–ankle–foot orthoses exerting corrective forces from five points along the full length of the limb was effective.Clinical relevance:The localization of the distal tibial correction, the quality of the midtibial correction band, and the importance of the application of corrective forces from five points with rigid methods were found.

scholarly journals Maternal behaviour in peripartum influences preweaning kit mortality in cage-bred wild rabbits.

2010 ◽  
Vol 18 (2) ◽  
pp. 91 ◽  
Author(s):  
  González-Redondo P.
Keyword(s):  
Survival Rates ◽  
Two Dimensions ◽  
Maternal Behaviour ◽  
Successful Development ◽  
Nest Box ◽  
High Incidence ◽  
Type 3 ◽  
Behaviour Type

This study describes and models maternal nest-building and parturition behaviour in cage-bred wild rabbits (oryctolagus cuniculus), and its influence on the kits’ pre-weaning mortality. In a total of 91 litters, perinatal mortality was 33%; mortality during the nursing period was 16.05%, and therefore the accumulated mortality up to weaning was 43.94%. These mortality rates, higher than those described in the literature among domestic breeds, were linked to failures in maternal behaviour. Such failures included the non-introduction of straw into the nest box (41.8% of births), a lack of hair lining in the nest (28.6%), births in which one or all of the kits were born outside the nest box (18.7%), and births in which one or all of the kits were cannibalised by the doe (13.2%). Maternal behaviour in relation to the kits’ viability was modelled by performing multiple correspondence and cluster analyses with two dimensions and a 67.2% total inertia. The fi rst dimension (inertia: 0.400) was represented by the presence of hair in the nest box; the place where the kits were born (inside or outside the nest box), and the doe’s previous experience (primiparous or multiparous), while the total number of kits born represents the second dimension (inertia: 0.272). Three maternal behaviour types were identified: types 1 and 3 representing births in which the failure of maternal behaviour at kindling led to high kit mortality. Maternal behaviour type 1 corresponds to primiparous does of parity orders 1 and 2 with a high number of total kits born and of stillborn kits. Type 3 births were characterised by all of the kits died during peripartum, with a high incidence of cannibalism. Type 2 included births of experienced does showing successful development of maternal behaviour, as well as high kits’ survival rates during the peripartum and nursing periods. Although wild rabbits are subject to the same modulating factors in the development of the maternal repertoire as domestic does, showed a lower preweaning viability due to the failure to display maternal behaviour during peripartum.<p class="MsoNormal"> </p>

scholarly journals Infestation of parasitic rhizocephalan barnacles Sacculina beauforti (Cirripedia, Rhizocephala) in edible mud crab, Scylla olivacea

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3419 ◽  
Author(s):  
Khor Waiho ◽  
Hanafiah Fazhan ◽  
Henrik Glenner ◽  
Mhd Ikhwanuddin
Keyword(s):  
Mud Crab ◽  
Mitochondrial Coi ◽  
Normal Individuals ◽  
Different Types ◽  
Rhizocephalan Barnacles ◽  
Commercially Important ◽  
The Mean ◽  
Type 3

Screening of mud crab genus Scylla was conducted in four locations (Marudu Bay, Lundu, Taiping, Setiu) representing Malaysia. Scylla olivacea with abnormal primary and secondary sexual characters were prevalent (approximately 42.27% of the local screened S. olivacea population) in Marudu Bay, Sabah. A total of six different types of abnormalities were described. Crabs with type 1 and type 3 were immature males, type 2 and type 4 were mature males, type 5 were immature females and type 6 were mature females. The abdomen of all crabs with abnormalities were dented on both sides along the abdomen’s middle line. Abnormal crabs showed significant variation in their size, weight, abdomen width and/or gonopod or pleopod length compared to normal individuals. The mean body weight of abnormal crabs (type 1–5) were higher than normal crabs with smaller body size, while females with type 6 abnormality were always heavier than the normal counterparts at any given size. Sacculinid’s externa were observed in the abdomen of crabs with type 4 and type 6 abnormalities. The presence of embryos within the externa and subsequent molecular analysis of partial mitochondrial COI region confirmed the rhizocephalan parasite as Sacculina beauforti. Future in-depth descriptions of the life cycle and characteristics of S. beauforti are recommended as it involves a commercially important edible crab species and the effect on human health from the consumption of crabs is of crucial concern.

scholarly journals Different Types of Periampullary Duodenal Diverticula Are Associated with Occurrence and Recurrence of Bile Duct Stones: A Case-Control Study from a Chinese Center

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Zhen Sun ◽  
Wenhui Bo ◽  
Ping Jiang ◽  
Quan Sun
Keyword(s):  
Acute Pancreatitis ◽  
Bile Duct ◽  
Control Group ◽  
Successful Cannulation ◽  
Cbd Stones ◽  
Duodenal Diverticula ◽  
Different Types ◽  
Type 3

Aims. We here investigated the association of different types of periampullary diverticula (PAD) with pancreaticobiliary disease and with technical success of endoscopic retrograde cholangiopancreatography (ERCP).Methods. A total of 850 consecutive patients who underwent their first ERCP were entered into a database. Of these patients, 161 patients (18.9%) had PAD and the age- and sex-matched control group comprised 483 patients.Results. PAD was correlated with common bile duct (CBD) stones (59.6% versus 35.0% in controls;P=0.008) and negatively correlated with periampullary malignancy (6.8% versus 21.5% in controls;P=0.004). The acute pancreatitis was more frequent (62.5%) in patients with PAD type 1 followed by PAD type 2 (28.9%,P=0.017) and type 3 (28.0%,P=0.006). No significant differences were observed in successful cannulation rate and post-ERCP complications among the 3 types of PAD. Type 1 PAD patients had less recurrence of CBD stones than did the patients who had type 2 or type 3 PAD (53.8% versus 85.7%;P=0.043).Conclusions. PAD, especially type 1 PAD, is associated with an increased acute pancreatitis as well as occurrence and recurrence of CBD stones. PAD during an ERCP should not be considered as an obstacle to a successful cannulation.

scholarly journals DEVELOPMENT, PERSISTENCE, AND SIGNIFICANCE OF TYPE 2, POLIOMYELITIS COMPLEMENT-FIXING ANTIBODY IN MAN

1952 ◽  
Vol 96 (1) ◽  
pp. 35-53 ◽  
Author(s):  
Jordi Casals ◽  
Peter K. Olitsky ◽  
Albert B. Sabin
Keyword(s):  
Complement Fixation ◽  
Age Groups ◽  
Neutralizing Antibody ◽  
Paralytic Poliomyelitis ◽  
Newborn Mice ◽  
History Of ◽  
Almost All ◽  
Type 3

Sera from 81 patients with a diagnosis of paralytic or non-paralytic poliomyelitis, and from 159 individuals of similar age groups giving no history of the disease, were tested with a high titered, complement-fixing poliomyelitis antigen of Type 2 (Lansing-like). The antigen consisted of brain tissue from newborn mice injected with the MEF1 strain of virus as previously adapted to these animals. The presence or absence of Type 2 neutralizing antibody in the sera under test was found not to affect the complement fixation. Positive reactions were obtained with 57 per cent of the sera deriving from non-paralytic patients and in 70 per cent from paralytics, when the specimens were tested at a dilution of 1:16. The complement-fixing antibody was often present in highest titer as early as 24 hours after the onset of poliomyelitis, and in almost all instances within 7 days. In about half of the patients a 4-fold or greater drop in titer occurred within 3 months, with little or no change in the others. The incidence of titers of 1:16 or higher with the control sera varied with the season of the year at which they were procured, 3 per cent of the winter samples proving positive and 13 per cent of the summer. The tests of sera from the group of patients from whom poliomyelitis virus was recovered, disclosed no significant differences between those having the paralytic and those having the non-paralytic disease. Type 1 (Brunhilde-like) strains of virus were recovered from many of the patients yielding positive tests, although they presented no evidence of previous or concurrent infection with Type 2 virus. This finding shows that Type 1 virus can give rise in patients to Type 2 complement-fixing antibody. The application of these data to the serologic diagnosis of poliomyelitis infection in man will of necessity be limited until information is obtained on the development, persistence, and significance of complement-fixation reactions with antigens deriving from Type 1 and Type 3 poliomyelitis strains.

scholarly journals Terminus behavior and response time of North Cascade glaciers, Washington, U.S.A.

2001 ◽  
Vol 47 (158) ◽  
pp. 497-506 ◽  
Author(s):  
Mauri S. Pelto ◽  
Cliff Hedlund
Keyword(s):  
Response Time ◽  
Mass Balance ◽  
Accumulation Rate ◽  
Initial Response ◽  
Ice Age ◽  
Different Types ◽  
Type 3 ◽  
Annual Balance

AbstractObservation of the terminus behavior of 38 North Cascade glaciers, Washington, U.S.A., since 1890 shows three different types of glacier response: (1) Continuous retreat from the Little Ice Age (LIA) advanced positions from 1890 to approximately 1950, followed by a period of advance from 1950 to 1976, and then retreat since 1976. (2) Rapid retreat from 1890 to approximately 1950, slow retreat or equilibrium from 1950 to 1976, and moderate to rapid retreat since 1976. (3) Continuous retreat from 1890 to the present.Type 1 glaciers are notable for steeper slopes, extensive crevassing and higher terminusregion velocities. Type 2 glaciers have intermediate velocities, moderate crevassing and intermediate slopes. Type 3 glaciers have low slopes, modest crevassing and low terminusregion velocities. This indicates that the observed differences in the response time and terminus behavior of North Cascade glaciers in reaction to climate change are related to variations in specific characteristics of the glaciers. The response time is approximately 20–30 years on type 1 glaciers, 40–60 years on type 2 glaciers and a minimum of 60–100 years on type 3 glaciers. The high correlation in annual balance between North Cascade glaciers indicates that microclimates are not the key to differences in behavior. Instead it is the physical characteristics — slope, terminus velocity, thickness and accumulation rate — of the glacier that determine recent terminus behavior and response time. The delay between the onset of a mass-balance change and initiation of a noticeable change in terminus behavior has been observed on 21 glaciers to be 4–16 years. This initial response time applies to both positive and negative changes in mass balance.

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