CARTILAGE BOUNDARY LUBRICATING ABILITY OF PRG4 (LUBRICIN) MONOMERS AND MULTIMERS WITH HYALURONAN

INTRODUCTION Proteoglycan 4 (PRG4), or lubricin, is a glycoprotein that exists in synovial fluid (SF) as monomeric and disulfide-bonded multimeric forms [1,2]. PRG4 functions as a critical boundary lubricant on the surface of articular cartilage [1,3]. Hyaluronan (HA) is another lubricant that lubricates at a cartilage-cartilage interface alone, and synergistically with PRG4 to reduce friction levels near that of SF [4]. Previously PRG4-multimers (PRG4-multi) have been shown to lubricate considerably better than PRG4 monomers (PRG4-mono) using an in vitro cartilage-on-cartilage friction testing system [5]. However, it is unknown if the difference in structure of PRG4-multi/-mono affects the synergism with HA. Therefore, the objective of this study was to evaluate the cartilage boundary lubricating ability of PRG4-multi & PRG4-mono with HA.   METHODS Samples: PRG4 was purified from media conditioned by mature bovine cartilage explants [4]. PRG4 multi-mono was prepared via size exclusion chromatography [5]. HA (1.5MDa) was obtained from Lifecore Biomedical. Cartilage boundary lubrication: Lubricants of interest were assessed using a previously described in vitro cartilage-cartilage friction test [6]. Briefly, bovine osteochondral samples (n=8) were incubated with test lubricants overnight, compressed by 18%, allowed to stress relax then rotated at an effective velocity of 0.3 mm/s with pre-sliding durations (Tps) of 1200, 120, 12, and 1.2s. Phosphate buffered saline (PBS) and bovine SF served as negative and positive controls, respectively. All samples were prepared at a physiological concentration [4]; PRG4 at 450 μg/mL and HA at 3.33 mg/mL, in PBS. Test sequence: PBS, PRG4-mono+HA, PRG4-multi+HA, PRG4+HA, SF. Static (μstatic,Neq) and kinetic (<μkinetic,Neq>) friction coefficients were calculated [4,6]. ANOVA was used to assess the effect of lubricant and Tps, as a repeated factor, on μstatic,Neq and <μkinetic,Neq>, with Tukey post-hoc on <μkinetic,Neq> at Tps=1.2s. RESULTS Cartilage boundary lubrication: PRG4-mono/-multi+HA, functioned as effective friction-reducing cartilage boundary lubricants. However, they did not lubricate as well as PRG4+HA or SF. μstatic,Neq values increased with Tps; they were highest in PBS and lowest in SF, with PRG4-mono+HA, PRG4-multi+HA, and PRG4+HA being intermediate. For clarity, <μkinetic,Neq> values at Tps=1.2s are shown since values at Tps=1.2s were within 13.0±2.7% of those at Tps=1200s. <μkinetic,Neq> values for PRG4-mono+HA and PRG4-multi+HA were similar (p=0.96). PRG4+HA and SF were similar (p=0.53). All other combinations were significantly different from each other (p<0.05). DISCUSSION AND CONCLUSIONS Previous studies have shown that PRG4-multi lubricates better than PRG4-mono [5]. However the results from this study show that PRG4-mono/-multi with HA lubricate in a similar manner. Interestingly, PRG4+HA lubricates better than PRG4-mono/-multi+HA, and close to that of SF. These differences could be due to a potential PRG4+HA “link molecule” [7] being purified from the PRG4-mono/-multi preparations

Contact angle and IFT measurements of smart water at elevated temperatures and pressures for evaluating wettability in a selected carbonate reservoir in the UAE

Water flooding has been regarded as a well-known secondary oil recovery method. In the recent years, extensive research on crude oil, brine, and rock systems has acknowledged that the composition of the injected water can change wetting properties of the reservoir during a water flood in a promising way to improve oil recovery. Hence, injection of “smart water” with correct salinity and composition is considered as a tertiary recovery method. The mechanism behind wettability alteration that is promoted by smart water injection has been a topic of discussion in carbonate and sandstone formations. In this work, some key properties of sea water and its dilutions with natural and spiked sulphate concentrations have been thoroughly investigated in the laboratory. Interfacial tension (IFT) of crude oil/brine system was monitored at ambient and high pressure-high temperature conditions. The brine with the least IFT was then used as a non-wetting phase with aged samples of rock for the measurement of contact angle at high pressure-high temperature conditions. The rock samples are carbonates of a selected onshore oil field in UAE. The results of this work show that sea water of salinity 57,539 mg/l without sulphate spiking may be considered as the smart water for further core flooding investigation

EFFECT OF COUNTERFACE ON CARTILAGE BOUNDARY LUBRICATING ABILITY BY HYALURONAN AND PROTEOGLYCAN 4: CARTILAGE-CARTILAGE VS CARTILAGE-GLASS

INTRODUCTION Proteoglycan 4 (PRG4), also known as lubricin, is a mucin-like glycoprotein found in synovial fluid (SF) [1]. Hyaluronan (HA) is another constituent of SF that works synergistically with PRG4 to promote joint lubrication required for joint health [2]. Current in vitro friction tests used to analyze these lubricants have found similar trends but varying friction coefficient (m) magnitudes. These effects may be attributed to different testing protocols, and in particular the various interfaces [3,4,5,6,7,8]. Previous studies have used cartilage-cartilage [7,8] and cartilage-glass [6] friction tests to assess SF lubricants. However, few studies have examined the friction reducing ability of SF lubricants at various velocities and different interfaces. The objective of this study was to determine HA and PRG4’s lubricating ability at cartilage-glass and cartilage-cartilage biointerfaces at various velocities.   METHODS HA (1.5 MDa, Lifecore Biomedical) was prepared at 3.3 mg/mL with phosphate buffered saline (PBS) [9]. PRG4 was purified from media conditioned bovine cartilage explants, and prepared at 450 μg/mL in PBS [9]. Two sets of tests were conducted using a modified boundary lubrication test protocol [7]. For cartilage-glass, a 6mm radius glass piece, with a root mean square surface roughness of 6.061±0.7554 nm, acted as the base core with a cartilage annuli [7]. Three lubricants were tested over three days, PBS (n=8), HA or PRG4 (n=4), and SF (n=8). Cartilage-cartilage underwent the same test sequence. Both sets of samples underwent the same testing protocol; samples were compressed to 18% of the total cartilage thickness with a 40 minute stress relaxation [9]. Samples were then rotated at effective sliding velocities of 10, 3, 1, 0.3, 0.1, and 0.01 mm/s with a 120s pre-sliding duration. Kinetic μ was calculated with instantaneous (<μkinetic>) load values. A two-factor ANOVA was used to determine effects of lubricant and velocity, with Tukey post-hoc testing. RESULTS At the cartilage-glass interface (Fig. 1A), <μkinetic> varied with test lubricant and velocity (p<0.001), with no interaction (p=0.78). All lubricants were significantly different from each other (p<0.001), except for PBS/HA (p=0.65) and PRG4/SF (p=0.72). Velocities were significantly different from each other when comparing 0.01 mm/s to all other speeds (p<0.02). At the cartilage-cartilage interface (Fig. 1B), <μkinetic> varied with test lubricant and velocity (p<0.01), with no interaction (p=0.82). All lubricants were significantly different from each other (p<0.01), except for HA/SF (p=0.07) and HA/PRG4 (p=0.35). Velocity was only significantly different at 0.01mm/s when compared to 3 and 10 mm/s (p<0.028). DISCUSSION AND CONCLUSIONS These results indicate that different articulating interfaces can result in different trends of <μkinetic>, and also affect the magnitude of the value. This agrees with previous research; showing that stiff and impermeable surfaces versus hydrated and permeable surfaces results in different <μkinetic> [3]. This data illustrates that HA is indeed a cartilage boundary lubricant and reduces friction at the cartilage-cartilage interface, but not at a cartilage-glass set up. Overall, different test systems are suitable for characterizing lubrication properties, but direct <μkinetic> values should not be compared

IMPLEMENTATION AND STUDY ON INNOVATIVE NEW TEACHING METHODS TO ENHANCE LEARNING OF MECHANICAL PRINCIPLES MODULE AT UNDERGRADUATE LEVEL

This paper is an outcome of the motivation and need to address wide spectrum of teaching and learning styles that are recognized by the students.  It is the order of the day that the student’s are encouraged in self-learning, engaged learning, peer to peer learning etc., forproviding better exposure and ambience for easy understanding of the basic concepts. In this context, Mechanical Principles module that is taught at undergraduate level at the Department of Mechanical engineering at Caledonian College of Engineering, Oman is considered for implementing new teaching tools.  This is a core module in mechanical engineering where the teaching involves a large group of students which require addressing pedagogical teaching and resource challenges. Various strategies are developed in order to enhance the teaching and learning experience of students such as change in layout of their seating arrangements inside the class room, use of soft tools for wider learning, open ended lab to improve the practical skills, use of CCE learn for online access of course documents, online quizzes for more interactive learning as well as access for students to video lectures &EBrary sources in addition to the traditional teaching. Survey conducted towards the level of satisfaction of students indicates that a majority of students appreciate different teaching and learning methods other than the traditional ones. The present work that is carried out for Mechanical principles module can be extended to other related modules. Definitely any useful teaching learning tools used in addition to the conventional methods of teaching creates attention to student community and enhances their theoretical and practical exposure

Comparison of Clinical Efficiency of Cention - N (With and Without Adhesive) and Composite Resin (Tetric N Ceram Bulk Fill) as Class 1 Restorations: A Randomized Controlled Clinical Trial

AIM OF THE STUDY: The aim of this study is to compare and evaluate the clinical efficiency of Cention N (with and without adhesive) and composite resin (Tetric N Ceram Bulk Fill) as class 1 restorations using Modified USPHS criteria. MATERIALS AND METHODS: This study is a single center prospective randomized controlled clinical trial. This study is about comparison of clinical performance of three different restorative system (Cention-N with adhesive, Cention-N without adhesive and Composite Resin) during 2 years of clinical service, using the Modified US public health service criteria. The restorations are evaluated at baseline, 6, 12, and 24 months. The study evaluates the following criteria--marginal discoloration (MD), marginal integrity (MI), surface texture (ST), wear(W), postoperative sensitivity (PS), recurrent caries (RC). RESULTS: At the end of 6,12 and 24 months, Cention N (with and without adhesive) exhibited acceptable clinical performance as comparable to that of resin composite (Tetric N Ceram Bull Fill) in terms of all parameters. Overall, Cention N with adhesive and Tetric N Ceram Bulk Fill was found to be marginally better than Cention N without adhesive but there was no statistically significant difference between them. CONCLUSION: Cention N with and without adhesive is found to be promising posterior restorative material with their clinical efficiency comparable to that of resin composite (Tetric N Ceram Bull Fill)

Identification of alternate dwarfing gene sources to widely used Dee-Gee-Woo-Gen allele of sd1 gene by molecular and biochemical assays in rice (Oryza sativa L.)

After the success of IR8 and TN1, breeders depended heavily on these two rice cultivars for source of short stature led to the narrow genetic base to majority of present day rice varieties, as far as sd1 (semi-dwarf1) gene is concerned. In addition, analysis of genetic lineage of the majority of the cultivated rice varieties in tropical Asia reveals that sd1 from DGWG (Dee-Gee-Woo-Gen) is the major source of dwarfing gene. Such high amount of genetic homogeneity renders rice plants vulnerable to epidemic of diseases and insect pests. In the current study, we made an attempt to identify the alternate sources of DGWG allele of sd1 gene by characterizing 29 induced and 3 spontaneous dwarf accessions employing marker for DGWG allele of sd1 gene and exogenous application of gibberellic acid (GA3). When occurrence of DGWG allele of sd1 gene and GA3 response were analyzed together, existence of two kinds of dwarfs was noticed viz., dwarf accessions with DGWG allele and dwarf accessions without DGWG allele of sd1 allele exhibiting varying responses to GA3. As many as 22 of 32 dwarf accessions showed absence of DGWG allele of sd1 gene with varying response to GA3 could be used as excellent alternate sources for DGWG allele of sd1 gene. These dwarf accessions could be used for broadening the genetic base for the plant height and thereby minimize the risk of genetic vulnerability. Our strategy of combining molecular and biochemical assays can be efficiently used for identifying alternate dwarfing gene sources to the Green Revolution gene sd1

An approach for an automatic fracture detection of skull DICOM images based on neighboring pixels

Providing easy access to Picture Archiving and Communications Systems (PACS) of selected image slices based on its diagnosis would be useful to teach medical students and educators and for government policies. This requires a simplified retrieval presenting only the key images to the doctors that has the diagnosis for every study of interest, thus saving doctors time. An automatic detection of diagnosis will help the radiographers in saving time since they consume a lot of time in the process of detecting skull fractures manually and with the automatic annotation of the pathological terms only to the key slices that has findings/diagnosis of the entire image set an efficient retrieval of specific key slices can be achieved. One important abnormality in the skull is its fracture. The proposed research goal concentrates on the automatic detection of normal and abnormal skull images as a part of our work. This paper presents a simple and fast automatic method to detect skull fracture in Digital Imaging and Communications in Medicine (DICOM) to extract the skull bone using histogram based thresholding and with the neighboring pixel connectivity search to identify the fracture. The experimental results of this approach are reliable with high detection rate

RELATIONSHIP BETWEEN DIFFERENT ALLOGAMIC ASSOCIATED TRAIT CHARACTERISTICS OF THE FIVE NEWLY DEVELOPED CYTOPLASMIC MALE STERILE (CMS) LINES IN RICE

Five suitable maintainer varieties were identifi ed through testcrosses with IR58025A and the transfer of wild abortive cytoplasm was carried out by seven successive backcrosses. Five new CMS lines were developed by this approach in well adapted high yielding improved varietal background such as ‘Nemat’, ‘Neda’, ‘Dasht’, ‘Amol3’ and ‘Champa’. Agronomical characterization and allogamy-associated traits of the fi ve newly developed CMS lines were studied for their interrelationship. Anther length had a signifi cant positive correlation with the duration of glume opening (0.759) and high correlation of (0.698) with the angle between lemma and palea. The results indicated that ‘Nemat’ A, ‘Neda’ A, ‘Dasht’ A are more suitable as parents for hybrid seed production due to their favorable and superior fl oral characteristics in comparison to IR58025A

A Critical Analysis On Right To Vote Of Prisoners

This paper aims to compare the right to vote for prisoners across the globe. Human rights are ethical principles or norms, that describe bound norms of human behavior, and customarily defend domestic and international laws. individuals usually understand them because of the "inalienable" basic rights that an individual has to himself. And notwithstanding age, race, location, language, religion, race, or alternative conditions, they're "common to all. they apply to every place and are continuously equivalent for everybody within the sense of generality and equality. It is understood that they need compassion, the rule of law, and therefore the personal obligation to respect the human rights of others. Unless it is the result of group action supported the circumstances of human rights and elections and therefore the right to participate publicly affairs including the proper to vote and campaign rights, it is typically not thought about that it will withdraw the democratic government based on the need of the Therefore, the $64000 alternative could be a necessary and basic part of the setting that protects and promotes human development. the proper to vote and the right to select real and regular elections are indivisible from an outsized range of alternative human rights, and the exercise of other human rights is essential to a purposeful election process. These predominate rights embody the proper to nondiscrimination, the right to freedom of speech and expression, the right to freedom of association and peaceful assembly, and therefore the right to freedom of movement. OHCHR is committed to making sure that elections fit international human rights standards and control in a setting where everybody will exercise their basic rights. Headquarters and field methods, as well as advocacy, technical assistance, human rights watching within the text of the election convention, and public or confidential reporting

Identification of alternate dwarfing gene sources to widely used Dee-Gee-Woo-Gen allele of sd1 gene by molecular and biochemical assays in rice ( Oryza sativa L.)

After the success of IR8 and TN1, breeders depended heavily on these two rice cultivars for source of short stature led to the narrow genetic base to majority of present day rice varieties, as far as sd1 (semi-dwarf1) gene is concerned. In addition, analysis of genetic lineage of the majority of the cultivated rice varieties in tropical Asia reveals that sd1 from DGWG (Dee-Gee-Woo-Gen) is the source of dwarfing gene. Such high amount of genetic homogeneity renders rice plants vulnerable to epidemic of diseases and insect pests. In the current study, we made an attempt to identify the alternate sources of DGWG allele of sd1 gene by characterizing 29 induced and 3 spontaneous dwarf accessions employing marker for DGWG allele of sd1 gene and exogenous application of gibberellic acid (GA3). When occurrence of DGWG allele of sd1 gene and GA3 response were analyzed together, existence of two kinds of dwarfs was noticed viz., dwarf accessions with DGWG allele and dwarf accessions without DGWG allele of sd1 allele exhibiting varying responses to GA3. As many as 22 of 32 dwarf accessions showed absence of DGWG allele of sd1 gene with varying response to GA3 could be used as excellent alternate sources for DGWG allele of sd1 gene. These dwarf accessions could be used for broadening the genetic base for the plant height and thereby minimize the risk of genetic vulnerability. Our strategy of combining molecular and biochemical assays can be efficiently used for identifying alternate dwarfing gene sources to the Green Revolution gene sd1