Marginal Bone Changes around Dental Implants after LIPUS Application: CBCT Study

To assess the effect of LIPUS on marginal bone regeneration during insertion and following loading using CBCT scan imaging, a trial of RCT of 22 subjects needing dental implant was conducted. The participants were randomly allocated into 2 groups; both groups underwent similar two-stage implant surgery of one maxillary dental implant. The control group (n = 11) of the implant site was allowed to heal in a conventional way, while the intervention group (n = 11) was subjected to LIPUS therapy at the implant site (twice a week, 20-minute duration, from week 2 after stage I implant surgery and continued for 10 weeks). Similar ultrasound protocol was repeated 2 weeks after crown installation and again continued for another 10 weeks. The assessment of marginal bone loss around dental implants was carried out at three different views (coronal, sagittal, and axial) of the implant site immediately after surgery, 3 and 6 months later. Statistical analysis of ANOVA within and between two-group analysis that was applied followed by pairwise comparison with confidence interval adjustment showed that there is a significant difference among the groups (p < 0.05). The CBCT imaging (coronal view) values suggested that bucccal bone regeneration around the dental implant has significantly increased during the early osseointegration period in the LIPUS-treated subjects than in the control group. LIPUS enhances bone formation in particular buccal bone plate around the dental implant as confirmed by the coronal view

Confusing the extragalactic neutrino flux limit with a neutrino propagation limit

We study the possible suppression of the extragalactic neutrino flux due to a nonstandard interaction during its propagation. In particular, we study neutrino interaction with an ultra-light scalar field dark matter. It is shown that the extragalactic neutrino flux may be suppressed by such an interaction, leading to a new mechanism to reduce the ultra-high energy neutrino flux. We study both the cases of non-self-conjugate as well as self-conjugate dark matter. In the first case, the suppression is independent of the neutrino and dark matter masses. We conclude that care must be taken when explaining limits on the neutrino flux through source acceleration mechanisms only, since there could be other mechanisms for the reduction of the neutrino flux.Comment: 15 pages, 4 figures. Important changes implemented. Abstract modified. Conclusions remain. To be published in JCA

The Motorcycle Design Parameter Database (MDPD) for Different Motorcycle Models

AbstractGlobally, motorcycle road accidents are increasing annually. Among the efforts in overcoming this dire scenario, motorcycle simulators were developed. The Postura MotergoTM which was developed by researchers at the Motorcycle Engineering Technology Lab (METAL) is an example of such simulators. The Postura MotergoTM has a unique capability in replicating various riding postures according to the Riding Posture Classification (RIPOC) system. However, there is the need for a novel database that gives information on the workstation design parameters of various motorcycles. Hence, a specifically built mannequin (the D5EM110N) was developed as a tool to measure various workstation dimensions on actual motorcycles. As of April 2015, the mannequin's design is being filed for an intellectual property (IP) protection. The motorcycles’ design parameters which were collected via the D5EM110N mannequin was then tabulated into the Motorcycle Design Parameter Database (MDPD). The database is then could be utilized to set up the Postura MotergoTM to accurately replicate the desired motorcycle model's workstation design parameters. This is vital in ensuring that the motorcycle simulator could accurately simulate an immersive user experience to the subject in utilizing the desired motorcycle model. By having this novel database and mannequin design, researchers have greater opportunity in conducting various studies in a controlled laboratory setting with respect to motorcycle workstation designs and its possible connection with road accidents

Characterization of Injection Molded 17-4PH Stainless Steel Prepared with Waste Rubber Binder

This study is to investigate the sintering characteristics and to establish the best heating rate and soaking time used for sintering process, by determining the physical, mechanical, and microstructural properties of the injection molded 17-4PH stainless steel using waste rubber as a new developed binder system. By using the feedstock which having 65 vol.% of metal powder, the molding are injected into the tensile test bar and immediately processed with two stage debinding process that involves of solvent extraction and thermal pyrolisis to remove the binder. The specimens were sintered at 1360°C under vacuum atmosphere and tested for a critical property analysis of tensile test. Later, the observation on tensile testedspecimens fracture surface are done to understand the fracture behavior,distribution of grain and porosity and the significant correlation of fracture morphology to the mechanical properties. From this study, it is found that the combination of 50C/min heating rate and 60 minutes of soaking period resulted in higher density value, higher tensile strength, less porosity and homogenous grains distribution of the sintered specimens

ELECTROMYOGRAPHY ANALYSIS ASSOCIATED WITH PROLONGED STANDING IN METAL STAMPING INDUSTRY

Many jobs in metal stamping industry require workers to perform in standing position. Standing is a practical working position when the workers are lifting heavy products, and pushing or pulling excessive loads because those jobs require a stable position and large degree of freedom. However, if the workers perform the jobs continuously in standing throughout the working hours, they may be experience muscle fatigue. The objective of this study such as to measure the myoelectric levels (μV) exerted by the left and right erector spinae, left and right tibialis anterior. The myoelectric levels in the muscles were measured using surface Electromyography (sEMG). Ten production workers from a metal stamping industry participated as subjects for sEMG measurement. Out of which, five workers from metal stamping process lines and another five from handwork section. The muscle activity of the subjects was measured for 5 hours and 45 minutes of continuous standing during beginning of workday, middle of workday, and end of workday from Monday to Wednesday. Results of comparison found that the two groups of workers show significant difference (p-value &lt; 0.05) in myoelectric level in the right erector spinae, right gastrocnemius, and left tibialis anterior during the beginning of workday. However, the two groups of workers did not show any significant difference in myoelectric level during the middle of the workday and end of the workday. It can be concluded that muscle activity of the workers was determined by the work load and duration of standing. This study suggests that anti fatigue mat and micro breaks should be provided to the workers to reduce muscle fatigue

Quark matter imprint on Gravitational Waves from oscillating stars

We discuss the possibility that the detection of gravitational waves emitted by compact stars may allow to constrain the MIT bag model of quark matter equation of state. Our results show that the combined knowledge of the frequency of the emitted gravitational wave and of the mass, or the radiation radius, of the source allows one to discriminate between strange stars and neutron stars and set stringent bounds on the bag constants.Comment: Eight pages, four figures. Revised version, to appear on General Relativity and Gravitatio

The Economic Impact of Optimizing a COVID-19 Management Protocol in Pre-Existing Cardiovascular Disease Patients

This study answers the question of whether the health care costs of managing COVID-19 in preexisting cardiovascular diseases (CVD) patients increased or decreased as a consequence of evidence-based efforts to optimize the initial COVID-19 management protocol in a CVD group of patients. A retrospective cohort study was conducted in preexisting CVD patients with COVID-19 in Hamad Medical Corporation, Qatar. From the health care perspective, only direct medical costs were considered, adjusted to their 2021 values. The impact of revising the protocol was a reduction in the overall costs in non-critically ill patients from QAR15,447 (USD 4243) to QAR4337 (USD 1191) per patient, with an economic benefit of QAR11,110 (USD 3051). In the critically ill patients, however, the cost increased from QAR202,094 (USD 55,505) to QAR292,856 (USD 80,433) per patient, with added cost of QAR90,762 (USD 24,928). Overall, regardless of critical care status, the optimization of the initial COVID-19 protocols in patients with preexisting CVD did not reduce overall health care costs, but increased it by QAR80,529 (USD 22,117) per patient

Clinical spectrum of SIX3-associated mutations in holoprosencephaly: correlation between genotype, phenotype and function

BACKGROUND: Holoprosencephaly (HPE) is the most common structural malformation of the human forebrain. There are several important HPE mutational target genes, including the transcription factor SIX3, which encodes an early regulator of Shh, Wnt, Bmp and Nodal signalling expressed in the developing forebrain and eyes of all vertebrates. OBJECTIVE: To characterise genetic and clinical findings in patients with SIX3 mutations. METHODS: Patients with HPE and their family members were tested for mutations in HPE-associated genes and the genetic and clinical findings, including those for additional cases found in the literature, were analysed. The results were correlated with a mutation-specific functional assay in zebrafish. RESULTS: In a cohort of patients (n = 800) with HPE, SIX3 mutations were found in 4.7% of probands and additional cases were found through testing of relatives. In total, 138 cases of HPE were identified, 59 of whom had not previously been clinically presented. Mutations in SIX3 result in more severe HPE than in other cases of non-chromosomal, non-syndromic HPE. An over-representation of severe HPE was found in patients whose mutations confer greater loss of function, as measured by the functional zebrafish assay. The gender ratio in this combined set of patients was 1.5:1 (F:M) and maternal inheritance was almost twice as common as paternal. About 14% of SIX3 mutations in probands occur de novo. There is a wide intrafamilial clinical range of features and classical penetrance is estimated to be at least 62%. CONCLUSIONS: Our data suggest that SIX3 mutations result in relatively severe HPE and that there is a genotype-phenotype correlation, as shown by functional studies using animal models