scholarly journals Role of an additional third screw in the fixation of transverse patellar fracture with two parallel cannulated screw and anterior wire

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Chih-Wei Chang ◽  
Chih-Hsien Chen ◽  
Chun-Ting Li ◽  
Yen-Nien Chen ◽  
Tai-Hua Yang ◽  
...  
Keyword(s):  
Knee Flexion ◽  
Cannulated Screw ◽  
Cannulated Screws ◽  
Full Extension ◽  
The Third ◽  
Gap Opening ◽  
Biomechanical Effect ◽  
The Stability ◽  
Patellar Fractures

Abstract Background Two parallel cannulated screws along with an anterior wire to construct a tension band is a popular approach in transverse patellar fractures. However, the optimal screw proximity, either deep or superficial screw placements, remains controversial. Hence, a new concept of the addition of a third screw to form a triangular configuration along with the original two parallel screws was proposed in this study. Therefore, the biomechanical effect of the additional third screw on the stability of the fractured patella was investigated with finite element (FE) simulation. Methods An FE knee model including the distal femur, proximal tibia, and fractured patella (type AT/OTA 34-C) was developed in this study. Four different screw configurations, including two parallel cannulated screws with superficial (5-mm proximity) and deep (10-mm proximity) placements and two parallel superficial screws plus a third deep screw, and two parallel deep screws plus a third superficial screw, with or without the anterior wire, were considered for the simulation. Results Results indicated that the addition of a third screw increased stability by reducing the dorsal gap opening when two parallel screws were deeply placed, particularly on the fractured patella without an anterior wire. However, the third screw was of little value when two parallel screws were superficially placed. In the existence of two deep parallel screws and the anterior wire, the third screw reduced the gap opening by 23.5% (from 1.15 mm to 0.88 mm) and 53.6% (from 1.21 mm to 0.61 mm) in knee flexion 45° and full extension, respectively. Furthermore, in the absence of the anterior wire, the third screw reduced the gap opening by 73.5% (from 2 mm to 0.53 mm) and 72.2% (from 1.33 mm to 0.37 mm) in knee flexion 45° and full extension, respectively. Conclusion Based on the results, a third cannulated screw superficially placed (5-mm proximity) is recommended to increase stability and maintain contact of the fractured patella, fixed with two parallel cannulated screws deeply placed (10-mm proximity), particularly when an anterior wire was not used. Furthermore, the third screw deeply placed is not recommended in a fractured patella with two parallel superficial screws.

The Role of Calcium in the Isolation of Brush Borders from Epithelial Cells of Rat Small Intestine

1966 ◽  
Vol 1 (4) ◽  
pp. 415-424
Author(s):  
P. F. MILLINGTON ◽  
D. R. CRITCHLEY ◽  
P.W. A. TOVELL
Keyword(s):  
Small Intestine ◽  
Calcium Ions ◽  
Chelating Agent ◽  
Tris Buffer ◽  
Good Separation ◽  
The Third ◽  
Low Concentrations ◽  
Brush Borders ◽  
The Stability

A chelating agent such as EDTA or EGTA used with a dilute TRIS buffer at pH 7.2-7.5 was used in order to effect a good separation of brush borders from the epithelium of the small intestine. A good separation was not obtained in low concentrations of TRIS buffer or saline alone. Brush borders were not obtained when the calcium-chelate complex of EDTA or EGTA was used, and only a partial fractionation was obtained when the magnesium complex of EDTA was tried. The involvement of calcium was further illustrated by adding calcium salts directly to the fractionation medium; separation was prevented when sufficient calcium had been added to saturate the chelating agent. It was found that there was no precise optimum concentration for EDTA but a separation could not be obtained below 2.4 mM/1. The effect of changing the pH of the buffer was also investigated and it was demonstrated that the onset of the ability to release brush borders coincided approximately with the ionization of the third acid radical of the chelating agent. This is in keeping with the suggested hypothesis that EDTA acts by chelating calcium ions. From these and electron-microscope studies it is suggested that the binding of calcium ions is an important factor in the maintenance of the stability of the epithelial cell membrane.

Results of the Experimental Research and Clinical Application of Cannulated Screw with Bioactive Coverage on the Basis of Natural Hydroxiapatite during Osteosynthesis of Medial Fractures of Femur’s Neck

2020 ◽  
Vol 46 ◽  
pp. 52-59
Author(s):  
Alexander Markov
Keyword(s):  
Cannulated Screw ◽  
Cannulated Screws ◽  
Experimental Systems ◽  
Experimental Stand ◽  
Accelerated Rehabilitation ◽  
Static Regime ◽  
Experimental Justification ◽  
The Stability ◽  
Natural Hydroxyapatite ◽  
Pauwels Classification

The goal of our research is clinical-experimental justification of differentiated application of osteosynthesis methodicsand application of cannulated screw with bioactive coverage on the basis of natural hydroxiapatitefor patients of old and senile age with the medial fracture of femur’s neck (MFFN) with taking into account the stability grade of fracture by Pauwels classification and motional activity of patients before trauma. The present research is based upon clinical observation of 110 old and senile patients with supcapital and transcervical femur’s neck fractures. With the purpose of scientific justification and detailed research of different types of MFFN osteosynthses experimental stand tests were conducted with the use of cannulated screws and methodic of vertical ostesynthesis by H. Kuntscher for determining and comparison of density and strength of experimental systems “fixator-bone” in static regime over MFFN models. Cannulated screws with bioactive coverage on the basis of natural hydroxyapatite were applied for 16 patients among all operated by us. Time of rehabilitation of supporting and motional functions of the limb has been decreased by using these implants among patients with grades I and II (by Pauwels classification). Thanks to osteoinductive and osteoconductive features of bioactive coverage on the basis of natural hydroxyapatite, rehabilitation of operated limb’s function was conducted in shorter terms and faster rate. For the purpose of obtaining the dynamic stability of osteosynthesis and conduction of accelerated rehabilitation cannulated cervical screw was developed and applied in practice. This screw is different in the design of spiral part and the presence on its surface of bioactive coverage on the basis of natural hydroxyapatite.

A Statistical Study of Process Variables to Optimize a High Speed Curtain Coater: Part I

TAPPI Journal ◽  
2009 ◽  
Vol 8 (1) ◽  
pp. 20-26 ◽  
Author(s):  
PEEYUSH TRIPATHI ◽  
MARGARET JOYCE ◽  
PAUL D. FLEMING ◽  
MASAHIRO SUGIHARA
Keyword(s):  
Boundary Layer ◽  
Experimental Design ◽  
High Speed ◽  
Statistical Study ◽  
Process Variables ◽  
High Speeds ◽  
The Stability ◽  
Air Removal ◽  
Removal System

Using an experimental design approach, researchers altered process parameters and material prop-erties to stabilize the curtain of a pilot curtain coater at high speeds. Part I of this paper identifies the four significant variables that influence curtain stability. The boundary layer air removal system was critical to the stability of the curtain and base sheet roughness was found to be very important. A shear thinning coating rheology and higher curtain heights improved the curtain stability at high speeds. The sizing of the base sheet affected coverage and cur-tain stability because of its effect on base sheet wettability. The role of surfactant was inconclusive. Part II of this paper will report on further optimization of curtain stability with these four variables using a D-optimal partial-facto-rial design.

A ‘Jurist-linguistic’ Reading of the wuḍūʾ Verse (Q. 5:6)

2010 ◽  
Vol 12 (1-2) ◽  
pp. 313-282
Author(s):  
ʿAbd al-ʿAzīz Mūsā
Keyword(s):  
The Third

This article sheds light on the role of grammar in understanding legislative texts, with reference to the wuḍūʾ verse (Q. 5:6). The first section deals with the issue of washing the elbows along with the feet as part of ritual ablution, and lists the various interpretations of the preposition ilā in the aya, and discusses the grammatical theory used by different fuqahāʾ to support their arguments. The second section tackles how much of the head should be rubbed in ritual ablution, with regard to the use of the preposition bi- in the phrase bi-ruʾūsikum, while the third focuses on the two readings of the phrase arjulakum/arjulikum (‘your feet’) and on passing legislative judgement on whether the feet be washed or just rubbed. The study concludes that lugha and fiqh theory are of mutual importance and together help to clarify legislative judgements, and, on this basis, that jurists should not pass any legislative judgement without referring to language.

Minangkabau Language Maintenance by the Association of Sei Jaring Community in Medan

2014 ◽  
Vol 11 (2) ◽  
Author(s):  
Yenita Uswar ◽  
Amrin Saragih ◽  
Tina Mariany Arifin
Keyword(s):  
Qualitative Research ◽  
Data Analysis ◽  
Language Maintenance ◽  
Young Generation ◽  
Third Generation ◽  
The Third ◽  
Danger Level

The objectives of this qualitative research were (1) to identify the factors that affect the Minangkabau language (ML) maintenance in Medan, (2) to discover the parents’ efforts in maintaining ML in Medan and (3) to find out the reason why the speakers have to maintain ML. The souree of data is the nembers of the Association of Sei Jaring Community (Ikatan Warga Sei Jaring: IWS) in Medan. The sample was 10 families including 10 parents and their children. The instruments of this study are a questionnaire and an interview. The questionnaire was used to answer the factors affected the maintenance of ML and how factors affected the maintenance of ML. The interview was used to discover the influence why Minangkabau’s people have to maintain ML. There are four factors in ML maintenance, the parents’ role, the role of family, the intramarriage and homeland visits. After distributing questionnaire and did some interviews it is found that IWS especially for the third generation (children) has the danger level in ML when they communicate to each other. Meanwhile, the data analysis also shows that both fathers and mothers communicate to each other with ML. This condition occurred because of the influence of the environment. Parents have to keep communication and teaching Minangkabau language continuously to their children. so, the young generation can keep the existence of ML for their future. Keywords: Minangkabau Language Maintenance, parents’ efforts, the young generation.

Zakat as a Measure of Social Justice in Islamic Finance : An Accountant’s Overview

2013 ◽  
Vol 1 (1) ◽  
pp. 64 ◽  
Author(s):  
Pranam Dhar
Keyword(s):  
Social Justice ◽  
Islamic Finance ◽  
Poverty Eradication ◽  
The Third ◽  
The Family ◽  
Additional Amount ◽  
Important Form

Zakat is an important form of religiously mandated charity under Islam. It is the third pillar of Islam. The giving of Zakat is important for Muslims, as this leads to purification of their wealth from all sins. This paper examines the role of Zakat as an instrument of social justice and poverty eradication in society. Each Muslim calculates his or her own Zakat individually. Generally, this involves the payment each year of two and a half percent of one's capital, after the needs of the family have been met. One can donate additional amount as an act of voluntary charity but Zakat is fundamental to every Muslim. Zakat is the Islamic contribution to social justice: those who have to give charity share the benefit of their prosperity to those who have fallen short. This is the Islamic approach to remove greed and envy and to purify one's soul based on good intentions. This is the institution of Zakat in Islam. The institution of Zakat serves to eradicate poverty in the community and uphold the light of Islam. Allah says “whatever is paid as Zakat for the sake of Allah shall be rewarded in manifolds”.

Do conhecimento objetivo ao problema corpo - mente

2018 ◽  
Vol 10 (2) ◽  
pp. 85-113
Author(s):  
Nathalia Gleyce dos Santos Salazar
Keyword(s):  
Third World ◽  
Sao Paulo ◽  
Karl Popper ◽  
São Paulo ◽  
Human Beings ◽  
The Third ◽  
Belo Horizonte ◽  
The Third World ◽  
The Mind

Resumo:  Apresenta-se uma discussão sobre o conhecimento e a tese dos três mundos no qual a interação entre estes nos aproxima da verdade do problema corpo-mente, tendo em vista, uma nova proposta de solução. O terceiro mundo é uma peça importante neste trabalho; sendo assim, analisaremos o que Popper designa como Mundo 3, em que ele consiste e o papel da linguagem como diferencial do ser humano. Apresentamos as críticas popperianas às correntes monistas e dualistas, ousando fazer uma crítica a Teoria do Conhecimento tradicional. Desta forma, a proposta apresentada por este filósofo da ciência diferencia-se de tudo que estava sendo feito até então, por isso, o interesse de apresentar essa abordagem pouco trabalhada de Popper. Palavras-chave: Conhecimento. Corpo-Mente. Mundo 3.Abstract: In this work, we present a discussion about knowledge and the theory of the three worlds in which the interaction between them approaches to the truth of the mind-body problem, in view of a proposed solution. The third world is an important piece in this work. Therefore, we will analyze what Popper describes as World 3, what it is and the role of language as a differential of human beings. We present Popper’s criticisms to the monistic and dualistic currents, daring to criticize the theory of traditional knowledge. Thus, the proposal of science presented by this philosopher differs from everything that was being done until then. This explains the interest in presenting this unusual approach to Popper.Keywords: Knowledge. Body-Mind.  World 3. REFERÊNCIASLEAL-TOLEDO, Gustavo . Popper e seu Cérebro. Revista da Faculdade de Letras. Série Filosofia, v. XXIII, p. 59-68, 2007.POPPER, Karl Raimund. A Lógica da Pesquisa Científica. Tradução de Leonidas Hegenberg e Octanny Silveira de Mota.  São Paulo: editora Cultrix. 2007.POPPER, Karl Raimund. Conhecimento Objetivo: uma abordagem evolucionária. Tradução de Milton Amado.  Belo Horizonte, Ed. Itatiaia Ilimitada. São Paulo, Ed. Da Universidade São Paulo, 1975._______.  O Conhecimento e o Problema Corpo –Mente. Tradução Joaquim Alberto Ferreira Gomes. Lisboa, Ed. 70. 1996.   _______. Conjecturas e Refutações: o desenvolvimento do conhecimento científico. Trad. Benedita Bettencourt. Ed. Livraria Almedina, 2006._______.  O Eu e Seu Cérebro. Karl Popper, Jonh C. Eccles;Tradução Silvio Meneses Garcia, Helena Cristina F. Arantes e Aurélio Osmar C. de Oliveira. – Campinas, SP: Papirus; Brasília, DF: Editora Universidade de Brasília. 1991.   _______. O Racionalismo Crítico na Política. Tradução de Maria da Conceição Côrte – Real. Brasília, Editora Universidade de Brasília, 2ª edição, 1994, 74p.SEARLE, John R. La construcción de la realidad social. Trad. Antoni Domènech. Barcelona: Paidós Ibérico, 1995.  

The Role of Hydrophobicity in the Stability and pH-Switchability of (RXDX)4 and Coumarin-RXDX Conjugate β-Sheets

2020 ◽  
Author(s):  
Ryan Weber ◽  
Martin McCullagh
Keyword(s):  
Biological Imaging ◽  
Ph Sensing ◽  
Hydrophobic Residue ◽  
Ideal Candidate ◽  
Self Assembling ◽  
Sensing Applications ◽  
Β Sheets ◽  
The Stability ◽  
Dynamics Simulations

<p>pH-switchable, self-assembling materials are of interest in biological imaging and sensing applications. Here we propose that combining the pH-switchability of RXDX (X=Ala, Val, Leu, Ile, Phe) peptides and the optical properties of coumarin creates an ideal candidate for these materials. This suggestion is tested with a thorough set of all-atom molecular dynamics simulations. We first investigate the dependence of pH-switchabiliy on the identity of the hydrophobic residue, X, in the bare (RXDX)<sub>4</sub> systems. Increasing the hydrophobicity stabilizes the fiber which, in turn, reduces the pH-switchabilty of the system. This behavior is found to be somewhat transferable to systems in which a single hydrophobic residue is replaced with a coumarin containing amino acid. In this case, conjugates with X=Ala are found to be unstable and both pHs while conjugates with X=Val, Leu, Ile and Phe are found to form stable β-sheets at least at neutral pH. The (RFDF)<sub>4</sub>-coumarin conjugate is found to have the largest relative entropy value of 0.884 +/- 0.001 between neutral and acidic coumarin ordering distributions. Thus, we posit that coumarin-(RFDF)<sub>4</sub> containing peptide sequences are ideal candidates for pH-sensing bioelectronic materials.</p>

Metal-Metal Cooperative Bond Activation by Heterobimetallic Alkyl, Aryl, and Acetylide PtII/CuI Complexes

2020 ◽  
Author(s):  
Shubham Deolka ◽  
Orestes Rivada Wheelaghan ◽  
Sandra Aristizábal ◽  
Robert Fayzullin ◽  
Shrinwantu Pal ◽  
...  
Keyword(s):  
Alkyl Group ◽  
Bond Activation ◽  
Bond Cleavage ◽  
Terminal Alkyne ◽  
Alkyl Aryl ◽  
Metal Metal ◽  
The Stability ◽  
Selective Formation ◽  
Organoplatinum Compounds

We report selective formation of heterobimetallic PtII/CuI complexes that demonstrate how facile bond activation processes can be achieved by altering reactivity of common organoplatinum compounds through their interaction with another metal center. The interaction of the Cu center with Pt center and with a Pt-bound alkyl group increases the stability of PtMe2 towards undesired rollover cyclometalation. The presence of the CuI center also enables facile transmetalation from electron-deficient tetraarylborate [B(ArF)4]- anion and mild C-H bond cleavage of a terminal alkyne, which was not observed in the absence of an electrophilic Cu center. The DFT study indicates that the role of Cu center acts as a binding site for alkyne substrate, while activating its terminal C-H bond.

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