Impact of mobile phone usage on dynamic postural control among South Indian college students

BACKGROUND

Smartphones are a technical marvel that rapidly evolved to play an important role in our lives. One downside to smartphone use is that it significantly worsens posture. It is believed that using a smartphone while walking increases the risk of cognitive decline and the loss of dynamic balance needed to perform functional tasks.

OBJECTIVE

The objective of the study was to determine the impact of smartphone usage on dynamic postural control among South Indian college students.

METHODS

The study was carried out in a private college with 400 invited students through online social media platforms. The four-square step test and SAS-SV were used to determine the impact of smartphone usage on dynamic postural control. The students were informed about the study process. A total of 250 participants were included based on the inclusion criteria.

RESULTS

There was a high percentage of agreement on smartphone usage on dynamic postural control measured with SAS-SV, revealing statistical significance with a mean value of 41.532 and SD of 10.010886. The four-square step test with a mean value of 22.5 and SD of 1.8995878 also proved significant impact. A positive correlation was found between smartphone usage and dynamic postural control, which was analysed using Pearson's correlation coefficient of 0.90130.

CONCLUSION

A significant correlation was noted between mobile usage and dynamic balance. Smartphones can have a negative impact on dynamic balance by distracting users from their surroundings and increase the risk of falls.

Kannada Translation and Validation of the ESAS-r Renal for Symptom Burden Survey in Patients with End-Stage Kidney Disease

Objectives

End-stage kidney disease (ESKD) is a life-limiting illness that leads to significant health-related suffering for the patients and their caregivers. Moreover, disease-directed options such as dialysis and renal transplant might not be universally accessible. Inadequate assessment and management of symptoms often lead to diminished quality of life. For evaluating symptoms and their associated distress, various tools have been identified. However, these are not available for the native Kannada-speaking population for assessing ESKD symptom burden. In this study, we determined the reliability and validity of the Edmonton Symptom Assessment System Revised Renal (ESAS-r: Renal) in Kannada-speaking ESKD patients.

Materials and Methods

ESAS-r: Renal English version was translated into Kannada using the forward and backward method. The translated version was endorsed by Nephrology, Palliative care, Dialysis technology and Nursing experts. As a pilot study, 12 ESKD patients evaluated the content of the questionnaires for appropriateness and relevance. The ESAS-r: Renal Kannada version was validated by administering this tool to 45 patients twice a fortnight.

Result

The translated ESAS-r: Renal Kannada version questionnaire had an acceptable face and content validity. Experts' opinion was assessed by content validity ratio (CVR), and the value of CVR of ESAS-r: Renal Kannada version was-'1'-. Internal consistency of the tool was assessed among Kannada-speaking ESKD patients; its Cronbach's α was 0.785, and test-retest validity was 0.896.

Conclusion

The validated Kannada version of ESAS-r: Renal was reliable and valid for assessing symptom burden in ESKD patients.

Effect of Educational Intervention on Knowledge and Level of Adherence among Hemodialysis Patients: A Randomized Controlled Trial

Purpose. The purpose of the study was to assess the impact of an educational intervention on the level of knowledge and adherence to the treatment regimen among hemodialysis (HD) patients as well as to describe the association between these variables. Methods. In this randomized controlled trial, 160 HD patients at an HD centre of a 2030-bed tertiary teaching hospital in Southern India were randomly assigned into intervention (N = 80, received education and a booklet) and control (N = 80, received standard care) groups. Knowledge and adherence were measured preintervention and postintervention using a validated questionnaire for knowledge and the ESRD-AQ (End-Stage Renal Disease Questionnaire) for the level of adherence. The statistical analysis of the data was performed with the help of the Statistical Program SPSS version 19.0. The statistical significance level was set at 0.05. Results. The increase in knowledge on disease management, fluid adherence, and dietary adherence in the intervention group was significantly higher compared to the control group. There was no significant correlation between knowledge and adherence. Adherence improved for all the domains, i.e., dialysis attendance, episodes of shortening, adherence to medication, fluid restriction, and dietary restriction. Adherence to fluid and dietary restriction was statistically significant. This trail is registered with https://clinicaltrials.gov/ct2/show/CTRI/2018/05/014166.

Acute Kidney Injury Post-Percutaneous Nephrolithotomy (PNL): Prospective Outcomes from a University Teaching Hospital

Acute Kidney Injury (AKI) after percutaneous nephrolithotomy (PNL) is a significant complication, but evidence on its incidence is bereft in the literature. The objective of this prospective observational study was to analyze the incidence of post-PNL AKI and the potential risk factors and outcomes. Demographic data collected included age, gender, body mass index (BMI), comorbidities (hypertension, diabetes mellitus), and drug history-particularly angiotensin converting enzyme inhibitors (ACE inhibitors), angiotensin II receptor blockers and beta blockers. Laboratory data included serial serum creatinine measured pre- and postoperation (12, 24, and 48 h), hemoglobin (Hb), total leucocyte count (TLC), Prothrombin time (PT), serum uric acid and urine culture. Stone factors were assessed by noncontrast computerized tomography of kidneys, ureter and bladder (NCCT KUB) and included stone burden, location and Hounsfield values. Intraoperative factors assessed were puncture site, tract size, tract number, operative time, the need for blood transfusion and stone clearance. Postoperative complications were documented using the modified Clavien-Dindo grading system and patients with postoperative AKI were followed up with serial creatinine measurements up to 1 year. Among the 509 patients analyzed, 47 (9.23%) developed postoperative AKI. Older patients, with associated hypertension and diabetes mellitus, those receiving ACE inhibitors and with lower preoperative hemoglobin and higher serum uric acid, had higher incidence of AKI. Higher stone volume and density, staghorn stones, multiple punctures and longer operative time were significantly associated with postoperative AKI. Patients with AKI had an increased length of hospital stay and 17% patients progressed to chronic kidney disease (CKD). Cut-off values for patient age (39.5 years), serum uric acid (4.05 mg/dL) and stone volume (673.06 mm3) were assessed by receiver operating characteristic (ROC) curve analysis. Highlighting the strong predictors of post-PNL AKI allows early identification, proper counseling and postoperative planning and management in an attempt to avoid further insult to the kidney.

Follow-Up Study on the Effect of Cognitive Behaviour Therapy on Haemodialysis Adherence: A randomised controlled trial

Objectives

Patients with chronic kidney disease (CKD) undergoing haemodialysis often experience a myriad of psychosocial problems, resulting in poor adherence to their therapeutic regimen. This study aimed to examine the effect of cognitive behaviour therapy (CBT) on dialysis, fluid, drug and diet adherence among a previously reported sample of CKD patients undergoing haemodialysis.

Methods

A randomised controlled trial was conducted between January 2013 to Febrary 2014 on a random selection of 67 CKD patients attending a tertiary multispecialty hospital in India. The experimental group (n = 33) was exposed to CBT, whereas the control group (n = 34) received non-directive counselling. A haemodialysis adherence scale was developed and used to assess adherence to the treatment regimen. The effect size was calculated using Cohen’s d statistics.

Results

At six months, mean reductions from baseline were observed in the experimental group in terms of interdialytic weight gain (−1.23 kg; effect size: 0.57), systolic blood pressure (−22.18 mmHg; effect size: 0.71) and diastolic blood pressure (−10.06 mmHg; effect size: 0.72), whereas mean increases were noted in haemoglobin (+0.75 g/dL; effect size: 0.31) and adherence to dialysis (+0.94; effect size: 0.51), fluids (+16.34; effect size: 2.30), diet (+61.19; effect size: 4.75) and drugs (+10.73; effect size: 1.3). Differences from baseline were significantly higher in the experimental group compared to the control group (P = 0.001 each).

Conclusion

These results show that CBT is more effective than non-directive counselling for improving therapeutic adherence and physiological, clinical parameters among CKD patients undergoing haemodialysis.

Oral manifestations in chronic kidney disease patients undergoing hemodialysis: a hospital-based study

BACKGROUND

Chronic kidney disease (CKD-HD) patients undergoing routine hemodialysis have been reported to have oral signs and symptoms due to disease process or various comorbidities like diabetes mellitus (DM). Both CKD and DM can cause oral changes. Hence this study aimed to evaluate the prevalence of oral symptoms and signs in CKD-HD patients and to rule out DM as possible confounding factor for the oral findings.

METHODS

Oral manifestations were assessed in 102 CKD-HD patients, and compared with 100 DM patients and 101 non-diabetic patients with no renal impairment.

RESULTS

Most common symptom reported by patients with CKD-HD were xerostomia, altered taste. The most prevalent objective findings were oral dryness. There was statistically significant difference in symptoms and signs between CKD-HD and non-CKD patients. However, no significant difference between CKD-HD with and without DM.

CONCLUSIONS

This study showed increased prevalence of oral findings in CKD patients. It also revealed that Diabetes mellitus cannot be a contributing factor for increased prevalence of oral manifestations in CKD patients.

Emergency brachial artery ligation for ruptured infected pseudoaneurysm of haemodialysis access is a possible option

Background:

For patients with end-stage renal disease, a good vascular access is essential for chronic haemodialysis. Surgically created access arteriovenous fistula for haemodialysis is associated with multiple complications, and ruptured pseudoaneurysm being the most life threatening and dreaded of all. The management of this complication warrants emergency procedure, although timely diagnosis and arteriovenous fistula salvage has been emphasised. In this study, we describe the surgical technique and outcomes of ligation of the proximal arteriovenous fistula as a plausible alternative and life-saving procedure.

Method and Results:

This is a retrospective study performed between January 2011 and December 2016. A total of 588 native arteriovenous fistula–related surgeries were performed, of which 18 patients (3.06%) developed delayed complication of infected pseudoaneurysm and rupture. All presented to the emergency care with life-threatening bleeding. We describe the surgical technique as a life-saving measure to this fatal complication.

Conclusion:

Proximal arteriovenous fistula has higher incidence of aneurysmal complications than distal ones. Ligation of the brachial artery which was a ‘grey zone’ of unpredictable prognosis has yielded good results and can be safely performed in desperate situations with low complication rates.

Evaluation of marginal and internal gaps of metal ceramic crowns obtained from conventional impressions and casting techniques with those obtained from digital techniques

BACKGROUND

Accuracy in fit of cast metal restoration has always remained as one of the primary factors in determining the success of the restoration. A well-fitting restoration needs to be accurate both along its margin and with regard to its internal surface.

AIM

The aim of the study is to evaluate the marginal fit of metal ceramic crowns obtained by conventional inlay casting wax pattern using conventional impression with the metal ceramic crowns obtained by computer-aided design and computer-aided manufacturing (CAD/CAM) technique using direct and indirect optical scanning.

MATERIALS AND METHODS

This in vitro study on preformed custom-made stainless steel models with former assembly that resembles prepared tooth surfaces of standardized dimensions comprised three groups: the first group included ten samples of metal ceramic crowns fabricated with conventional technique, the second group included CAD/CAM-milled direct metal laser sintering (DMLS) crowns using indirect scanning, and the third group included DMLS crowns fabricated by direct scanning of the stainless steel model. The vertical marginal gap and the internal gap were evaluated with the stereomicroscope (Zoomstar 4); post hoc Turkey's test was used for statistical analysis. One-way analysis of variance method was used to compare the mean values.

RESULTS AND CONCLUSION

Metal ceramic crowns obtained from direct optical scanning showed the least marginal and internal gap when compared to the castings obtained from inlay casting wax and indirect optical scanning. Indirect and direct optical scanning had yielded results within clinically acceptable range.

Development and validation of a physical model to investigate the biomechanics of infant head impact

Head injury in childhood is the single most common cause of death or permanent disability from injury. However, despite its frequency and significance, there is little understanding of the response of a child's head to injurious loading. This is a significant limitation when making early diagnoses, informing clinical and/or forensic management or injury prevention strategies. With respect to impact vulnerability, current understanding is predominantly based on a few post-mortem-human-surrogate (PMHS) experiments. Researchers, out of experimental necessity, typically derive acceleration data, currently an established measure for head impact vulnerability, by calculation. Impact force is divided by the head mass, to produce a "global approximation", a single-generalised head response acceleration value. A need exists for a new experimental methodology, which can provide specific regional or localised response data. A surrogate infant head, was created from high resolution computer tomography scans with properties closely matched to tissue response data and validated against PMHS head impact acceleration data. The skull was 3D-printed from co-polymer materials. The brain, represented as a lumped mass, comprised of an injected gelatin/water mix. High-Speed Digital-Image-Correlation optically measured linear and angular velocities and accelerations, strains and strain rates. The "global approximation" was challenged by comparison with regional and local acceleration data. During impacts, perpendicular (at 90°) to a surface, regional and local accelerations were up to three times greater than the concomitant "global" accelerations. Differential acceleration patterns were very sensitive to impact location. Suture and fontanelle regions demonstrated ten times more strain (103%/s) than bone, resulting in skull deformations similar in magnitude to those observed during child birth, but at much higher rates. Surprisingly, perpendicular impacts produced significantly greater rotational velocities and accelerations, which are closer to current published injury thresholds than expected, seemingly as a result of deformational changes to the complex skull geometry. The methodology has proven a significant new step in characterising and understanding infant head injury mechanics.

The geometric effects of a woodpecker's hyoid apparatus for stress wave mitigation

In this study a woodpecker's hyoid apparatus was characterized to determine its impact mitigation mechanism using finite element (FE) analysis. The woodpecker's hyoid apparatus, comprising bone and muscle, has a unique geometry compared to those of other birds. The hyoid starts at the beak tip, surrounds the woodpecker's skull, and ends at the upper beak/front head intersection while being surrounded by muscle along the whole length. A FE model of the hyoid apparatus was created based on the geometry, microstructure, and mechanical properties garnered from our experimental measurements. We compared the impact mitigation capabilities of the hyoid apparatus with an idealized straight cylinder and a tapered cylinder. The results showed that the hyoid geometry mitigated a greater amount of pressure and impulse compared to the straight or tapered cylinders. The initially applied longitudinal wave lost its strength from attenuation and conversion to transverse shear waves. This is due to the spiral curvature and tapered geometry, which induced lateral displacement in the hyoid bone. The lateral displacement of the bony hyoid induced strains on the adjacent muscle, where the energy dissipated due to the muscle's viscoelasticity. Quantitatively, as the stress wave traveled from the anterior to the posterior end of the hyoid apparatus, its pressure decreased 75% and the associated impulse decreased 84%. The analysis of the woodpecker's hyoid apparatus provides a novel perspective on impact mitigation mediated by a spiral-shaped structure and viscoelastic biocomposite.

Measurement of the centrality dependence of the charged-particle pseudorapidity distribution in proton-lead collisions at [Formula: see text] TeV with the ATLAS detector

The centrality dependence of the mean charged-particle multiplicity as a function of pseudorapidity is measured in approximately 1 [Formula: see text]b[Formula: see text] of proton-lead collisions at a nucleon-nucleon centre-of-mass energy of [Formula: see text] [Formula: see text] using the ATLAS detector at the Large Hadron Collider. Charged particles with absolute pseudorapidity less than 2.7 are reconstructed using the ATLAS pixel detector. The [Formula: see text] collision centrality is characterised by the total transverse energy measured in the Pb-going direction of the forward calorimeter. The charged-particle pseudorapidity distributions are found to vary strongly with centrality, with an increasing asymmetry between the proton-going and Pb-going directions as the collisions become more central. Three different estimations of the number of nucleons participating in the [Formula: see text] collision have been carried out using the Glauber model as well as two Glauber-Gribov inspired extensions to the Glauber model. Charged-particle multiplicities per participant pair are found to vary differently for these three models, highlighting the importance of including colour fluctuations in nucleon-nucleon collisions in the modelling of the initial state of [Formula: see text] collisions.

Quantum correlations in quenched disordered spin models: Enhanced order from disorder by thermal fluctuations

We investigate the behavior of quantum correlations of paradigmatic quenched disordered quantum spin models, viz., the XY spin glass and random-field XY models. We show that quenched averaged quantum correlations can exhibit the order-from-disorder phenomenon for finite-size systems as well as in the thermodynamic limit. Moreover, we find that the order-from-disorder can become more pronounced in the presence of temperature by suitable tuning of the system parameters. The effects are found for entanglement measures as well as for information-theoretic quantum correlation ones, although the former show them more prominently. We also observe that the equivalence between the quenched averages and their self-averaged cousins--for classical and quantum correlations--is related to the quantum critical point in the corresponding ordered system.

Quantum discord length is enhanced while entanglement length is not by introducing disorder in a spin chain

Classical correlation functions of ground states typically decay exponentially and polynomially, respectively, for gapped and gapless short-range quantum spin systems. In such systems, entanglement decays exponentially even at the quantum critical points. However, quantum discord, an information-theoretic quantum correlation measure, survives long lattice distances. We investigate the effects of quenched disorder on quantum correlation lengths of quenched averaged entanglement and quantum discord, in the anisotropic XY and XYZ spin glass and random field chains. We find that there is virtually neither reduction nor enhancement in entanglement length while quantum discord length increases significantly with the introduction of the quenched disorder.

Fulminant necrotising amoebic colitis: A diagnostic conundrum

Fulminant necrotising amoebic colitis is a complication of untreated amoebiasis. This is seen in mainly low-income countries. It has a high mortality rate and is difficult to diagnose. We present an extremely rare case of fulminant necrotising amoebic colitis that caused diagnostic confusion in mimicking an acute abdomen, presumably caused by a perforated duodenal ulcer.

Sprue design alterations and its effect on the properties of base metal alloy castings: An in vitro study

Introduction:

To study the effect of various sprue designs on the properties of base metal alloy castings. The base metal alloys are extensively used for their excellent properties such as an increase in hardness, high melting range, high elastic modulus, its compatibility with ceramic material and low cost. However, to improve the properties of the base metal alloys is an ongoing research leading to various modifications in their fabrication procedure – which include sprue designs and their mode of attachment to the wax pattern.

Aims and Objectives:

Study compared the effect of three sprue designs viz. conical sprue, cylindrical sprue and bottleneck sprue on the properties of mass and microhardness of base metal alloy castings.

Materials and Methods:

A prefabricated wax mesh pattern was selected for the fabrication of the alloy test samples in the study. The cylindrical sprue design was connected to the mesh pattern with a straight attachment. The bottleneck sprue design was connected to the mesh pattern with a constricted attachment. The conical sprue design was connected to the mesh pattern with a flared attachment. In this manner, ten samples for each of the three different sprue designs were prepared.

Results:

The obtained value for mass and microhardness were subjected to statistical analysis. ANOVA test was performed to determine the difference between the sprue designs.

Conclusion:

The bottleneck sprue, conical sprue, and cylindrical sprue designs did not exert any apparent influence on the mass and microhardness.

Clinical evaluation of direct composite restoration done for midline diastema closure - long-term study

Purpose of the Study:

The aim of this study was to evaluate clinically the performance of composite resin used to restore midline diastema between the maxillary and mandibular central incisors.

Methodology:

Direct composite restorations were done for 45 patients with midline diastema between the maxillary and mandibular central incisors. Standard protocols were followed for the placement of composite resin for the diastema closure, and recall visits were made for every 6 months for a period of 60 months for evaluation of the success of these restorations made. Qualified dental personnel examined the restorations made.

Results:

Clinical evaluations were done after the restorations had been in place for an average of 6 months. Results indicate that none of the restorations were totally lost, and resulting in a 91% overall retention rate for the period of 60 months. About 62% of the restorations made had no noticeable color difference with that of the adjacent tooth, and gingival health indicated 73% of the sample was without any signs of inflammation.

Conclusions:

Composites restored for diastemas exhibit satisfactory survival rates placed with recommended placement protocols and without occlusal loading.

Jet energy measurement and its systematic uncertainty in proton-proton collisions at [Formula: see text] TeV with the ATLAS detector

The jet energy scale (JES) and its systematic uncertainty are determined for jets measured with the ATLAS detector using proton-proton collision data with a centre-of-mass energy of [Formula: see text] TeV corresponding to an integrated luminosity of [Formula: see text][Formula: see text]. Jets are reconstructed from energy deposits forming topological clusters of calorimeter cells using the anti-[Formula: see text] algorithm with distance parameters [Formula: see text] or [Formula: see text], and are calibrated using MC simulations. A residual JES correction is applied to account for differences between data and MC simulations. This correction and its systematic uncertainty are estimated using a combination of in situ techniques exploiting the transverse momentum balance between a jet and a reference object such as a photon or a [Formula: see text] boson, for [Formula: see text] and pseudorapidities [Formula: see text]. The effect of multiple proton-proton interactions is corrected for, and an uncertainty is evaluated using in situ techniques. The smallest JES uncertainty of less than 1 % is found in the central calorimeter region ([Formula: see text]) for jets with [Formula: see text]. For central jets at lower [Formula: see text], the uncertainty is about 3 %. A consistent JES estimate is found using measurements of the calorimeter response of single hadrons in proton-proton collisions and test-beam data, which also provide the estimate for [Formula: see text] TeV. The calibration of forward jets is derived from dijet [Formula: see text] balance measurements. The resulting uncertainty reaches its largest value of 6 % for low-[Formula: see text] jets at [Formula: see text]. Additional JES uncertainties due to specific event topologies, such as close-by jets or selections of event samples with an enhanced content of jets originating from light quarks or gluons, are also discussed. The magnitude of these uncertainties depends on the event sample used in a given physics analysis, but typically amounts to 0.5-3 %.

Geometric effects on stress wave propagation

The present study, through finite element simulations, shows the geometric effects of a bioinspired solid on pressure and impulse mitigation for an elastic, plastic, and viscoelastic material. Because of the bioinspired geometries, stress wave mitigation became apparent in a nonintuitive manner such that potential real-world applications in human protective gear designs are realizable. In nature, there are several toroidal designs that are employed for mitigating stress waves; examples include the hyoid bone on the back of a woodpecker's jaw that extends around the skull to its nose and a ram's horn. This study evaluates four different geometries with the same length and same initial cross-sectional diameter at the impact location in three-dimensional finite element analyses. The geometries in increasing complexity were the following: (1) a round cylinder, (2) a round cylinder that was tapered to a point, (3) a round cylinder that was spiraled in a two dimensional plane, and (4) a round cylinder that was tapered and spiraled in a two-dimensional plane. The results show that the tapered spiral geometry mitigated the greatest amount of pressure and impulse (approximately 98% mitigation) when compared to the cylinder regardless of material type (elastic, plastic, and viscoelastic) and regardless of input pressure signature. The specimen taper effectively mitigated the stress wave as a result of uniaxial deformational processes and an induced shear that arose from its geometry. Due to the decreasing cross-sectional area arising from the taper, the local uniaxial and shear stresses increased along the specimen length. The spiral induced even greater shear stresses that help mitigate the stress wave and also induced transverse displacements at the tip such that minimal wave reflections occurred. This phenomenon arose although only longitudinal waves were introduced as the initial boundary condition (BC). In nature, when shearing occurs within or between materials (friction), dissipation usually results helping the mitigation of the stress wave and is illustrated in this study with the taper and spiral geometries. The combined taper and spiral optimized stress wave mitigation in terms of the pressure and impulse; thus providing insight into the ram's horn design and woodpecker hyoid designs found in nature.

Muon reconstruction efficiency and momentum resolution of the ATLAS experiment in proton-proton collisions at [Formula: see text] TeV in 2010

This paper presents a study of the performance of the muon reconstruction in the analysis of proton-proton collisions at [Formula: see text] TeV at the LHC, recorded by the ATLAS detector in 2010. This performance is described in terms of reconstruction and isolation efficiencies and momentum resolutions for different classes of reconstructed muons. The results are obtained from an analysis of [Formula: see text] meson and [Formula: see text] boson decays to dimuons, reconstructed from a data sample corresponding to an integrated luminosity of 40 pb[Formula: see text]. The measured performance is compared to Monte Carlo predictions and deviations from the predicted performance are discussed.

Casting made simple using modified sprue design: an in vitro study

BACKGROUND

Success in dental casting restorations for fixed partial dentures (FPDs) depends on the castability. Castability is described as the ability of an alloy to faithfully reproduce sharp detail and fine margins of a wax pattern. The goal of a prosthodontist is to provide the patient with restorations that fit precisely. Regardless of the alloy used for casting, the casting technique should yield a casted alloy, which should possess sufficient mass, surface hardness and minimal porosity after casting.

MATERIALS AND METHODS

Twenty patterns for casting were made from three-dimensional printed resin pattern simulating a 3 unit FPD and casted using modified sprue technique. Later test samples were cemented sequentially on stainless steel model using pressure indicating paste and evaluated for vertical marginal gap in eight predetermined reference areas. Marginal gap were measured in microns using Video Measuring System (VMS2010F-CIP Corporation, Korea). A portion of the axial wall of the cast abutments depicting premolar and molar were sectioned and embedded in acrylic resin and tested for micro hardness using Reichert Polyvar 2 Met Microhardness tester (Reichert, Austria) and porosity using Quantimet Image Analyzer (Quantimet Corporation London, England).

RESULTS

The results obtained for marginal gap, micro hardness, and porosity of all test samples were tabulated, descriptive statistics were calculated and the values were found to be within the clinically acceptable range.

CONCLUSION

The new sprue technique can be an alternative and convenient method for casting which would minimize metal wasting and less time consuming. However, further studies with same technique on various parameters are to be conducted for its broad acceptance.

Electron reconstruction and identification efficiency measurements with the ATLAS detector using the 2011 LHC proton-proton collision data

Many of the interesting physics processes to be measured at the LHC have a signature involving one or more isolated electrons. The electron reconstruction and identification efficiencies of the ATLAS detector at the LHC have been evaluated using proton-proton collision data collected in 2011 at [Formula: see text] TeV and corresponding to an integrated luminosity of 4.7 fb[Formula: see text]. Tag-and-probe methods using events with leptonic decays of [Formula: see text] and [Formula: see text] bosons and [Formula: see text] mesons are employed to benchmark these performance parameters. The combination of all measurements results in identification efficiencies determined with an accuracy at the few per mil level for electron transverse energy greater than 30 GeV.

The differential production cross section of the [Formula: see text](1020) meson in [Formula: see text] = 7 TeV [Formula: see text] collisions measured with the ATLAS detector

A measurement is presented of the [Formula: see text] production cross section at [Formula: see text] = 7 TeV using [Formula: see text] collision data corresponding to an integrated luminosity of 383 [Formula: see text], collected with the ATLAS experiment at the LHC. Selection of [Formula: see text](1020) mesons is based on the identification of charged kaons by their energy loss in the pixel detector. The differential cross section is measured as a function of the transverse momentum, [Formula: see text], and rapidity, [Formula: see text], of the [Formula: see text](1020) meson in the fiducial region 500 [Formula: see text] 1200 MeV, [Formula: see text] 0.8, kaon [Formula: see text] 230 MeV and kaon momentum [Formula: see text] 800 MeV. The integrated [Formula: see text]-meson production cross section in this fiducial range is measured to be [Formula: see text] = 570 [Formula: see text] 8 (stat) [Formula: see text] 66 (syst) [Formula: see text] 20 (lumi) [Formula: see text].

A Comparison of Dimensional Accuracy of Addition Silicone of Different Consistencies with Two Different Spacer Designs - In-vitro Study

INTRODUCTION

Dimensional accuracy of impression materials is crucial for the production of working casts in Fixed Prosthodontics. The accurate replication of tooth preparations and their arch position requires impression materials that exhibit limited distortion.

METHODS

This study was conducted to comparatively evaluate the dimensional accuracy of additional silicones by comparing two different techniques and spacer designs, by measuring the linear changes in interpreparation distance. The impressions were made from a stainless steel master die simulating a three unit bridge. A total 80 die stone (type IV, Ultrarock) models were obtained from the impressions made using two different parameters. The two different parameters are Multimix and Monophasic technique and different spacer designs.

RESULT

The interpreparation distance of the abutments in the casts was measured using a travelling microscope. Each sample was measured thrice and the mean value was calculated. The results obtained were statistically analysed and the values fall within the clinically acceptable range.

CONCLUSION

The most accurate combination is multimix technique with spacer design which uses less bulk of impression material.

Search for quantum black hole production in high-invariant-mass lepton+jet final states using pp collisions at √s=8 TeV and the ATLAS detector

This Letter presents a search for quantum black-hole production using 20.3 fb-1 of data collected with the ATLAS detector in pp collisions at the LHC at √s = 8 TeV. The quantum black holes are assumed to decay into a final state characterized by a lepton (electron or muon) and a jet. In either channel, no event with a lepton-jet invariant mass of 3.5 TeV or more is observed, consistent with the expected background. Limits are set on the product of cross sections and branching fractions for the lepton+jet final states of quantum black holes produced in a search region for invariant masses above 1 TeV. The combined 95% confidence level upper limit on this product for quantum black holes with threshold mass above 3.5 TeV is 0.18 fb. This limit constrains the threshold quantum black-hole mass to be above 5.3 TeV in the model considered.

Search for dark matter in events with a hadronically decaying W or Z boson and missing transverse momentum in pp collisions at √s=8 TeV with the ATLAS detector

A search is presented for dark matter pair production in association with a W or Z boson in pp collisions representing 20.3  fb(-1) of integrated luminosity at √s=8  TeV using data recorded with the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet with the jet mass consistent with a W or Z boson, and with large missing transverse momentum are analyzed. The data are consistent with the standard model expectations. Limits are set on the mass scale in effective field theories that describe the interaction of dark matter and standard model particles, and on the cross section of Higgs production and decay to invisible particles. In addition, cross section limits on the anomalous production of W or Z bosons with large missing transverse momentum are set in two fiducial regions.

Measurement of jet shapes in top-quark pair events at [Formula: see text] using the ATLAS detector

A measurement of jet shapes in top-quark pair events using 1.8 fb-1 of [Formula: see text]pp collision data recorded by the ATLAS detector at the LHC is presented. Samples of top-quark pair events are selected in both the single-lepton and dilepton final states. The differential and integrated shapes of the jets initiated by bottom-quarks from the top-quark decays are compared with those of the jets originated by light-quarks from the hadronic W-boson decays [Formula: see text] in the single-lepton channel. The light-quark jets are found to have a narrower distribution of the momentum flow inside the jet area than b-quark jets.

Measurement of top quark polarization in top-antitop events from proton-proton collisions at √s=7 TeV using the ATLAS detector

This Letter presents measurements of the polarization of the top quark in top-antitop quark pair events, using 4.7  fb(-1) of proton-proton collision data recorded with the ATLAS detector at the Large Hadron Collider at √s=7  TeV. Final states containing one or two isolated leptons (electrons or muons) and jets are considered. Two measurements of α(ℓ)P, the product of the leptonic spin-analyzing power and the top quark polarization, are performed assuming that the polarization is introduced by either a CP conserving or a maximally CP violating production process. The measurements obtained, α(ℓ)P(CPC)=-0.035±0.014(stat)±0.037(syst) and α(ℓ)P(CPV)=0.020±0.016(stat)(-0.017)(+0.013)(syst), are in good agreement with the standard model prediction of negligible top quark polarization.

Measurement of the azimuthal angle dependence of inclusive jet yields in Pb+Pb collisions at √(sNN)=2.76 TeV with the ATLAS detector

Measurements of the variation of inclusive jet suppression as a function of relative azimuthal angle, Δφ, with respect to the elliptic event plane provide insight into the path-length dependence of jet quenching. ATLAS has measured the Δφ dependence of jet yields in 0.14 nb(-1) of √(s(NN))=2.76 TeV Pb+Pb collisions at the LHC for jet transverse momenta p(T)>45 GeV in different collision centrality bins using an underlying event subtraction procedure that accounts for elliptic flow. The variation of the jet yield with Δφ was characterized by the parameter, v(2)(jet), and the ratio of out-of-plane (Δφ~π/2) to in-plane (Δφ~0) yields. Nonzero v(2)(jet) values were measured in all centrality bins for p(T)<160 GeV. The jet yields are observed to vary by as much as 20% between in-plane and out-of-plane directions.