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The next-generation wireless communication systems including satellite, radar, and mobile communications need application-specific power amplifiers that can operate at very high frequencies and high power with the overall minimum power consumption from the system. To meet such stringent requirements there is a rising interest in amplifier designs based on GaN transistors. This paper presents an improved design of a high power amplifier based on GaN HEMT transistor operating at the frequency band 5GHz – 7GHz with optimized output power level. The presented design is based on a 12 Watt Discrete Power GaN on SiC HEMT from TriQuint. In this manuscript, we have considered the stability of the amplifier for the whole operating frequency band, its input and output matching impedance, gain, and maximum output power. The design of the Radio Frequency (RF) power amplifier and its overall performance are carried out using an advanced design system (ADS). The simulation results of the device stability and the output power level achieved provides a good comparison with the parameters and specifications of the device used. For better correlations in the simulation results and measurements, the accuracy of passive element designs are also considered. The simulation and experiment results show that the designed high power amplifier has achieved an output power level of 44.5 dBm at 1 dB compression point.

Objective: To assess the reliability of gingival crevicular blood as a diagnostic tool for diabetes in patients with periodontal disease with and without diabetes. Study Design: Cross sectional study. Place and Duration of Study: Department of Periodontics, Jinnah Medical and Dental College, Karachi, Pakistan, from Jul 2017 to Jul 2018. Methodology: Forty patients with diabetes and 60 patients without diabetes with mild to moderate gingivitis or periodontitis in either the upper or lower anterior region were included. Gingival crevicular blood (GCB) was collected and was assessed by glucometer. The same patient underwent finger stick blood (FSB) and intravenous blood glucose level (IV). Plaque Index (PI), Periodontal Pocket Depth (PPD) and Gingival index were also recorded. Results: A positive correlation (r) was detected between glucose levels of Gingival crevicular blood with finger stick blood with the value of coefficient correlation ‘r’=0.849. The mean values of Gingival index in patients without diabetes is 1.53 ± 0.97mm, patients with newly diagnosed diabetes is 1.87 ± 0.920mm and without diabetes is 2.13± 0.94mm. Conclusion: Blood glucose level can be assessed with the help of Gingival crevicular blood as this technique was found easy and non-invasive to the patient and it can help in diagnosing diabetes during regular periodontal treatment.

The development of inexpensive cocatalysts based on earth-abundant-elements, is highly demanding strategy to produce large-scale photocatalytic H2 for real-life applications. Herein, we report the utilization of CoSe as a highly efficient cocatalyst to significantly improve the photocatalytic H2 production on ZnSe/CdS under visible irradiation. The maximum H2 production rate of 785 μmol h−1 was attained under optimized conditions. Furthermore, the current system showed robust stability up to 30 h of irradiation and more than 23 mmol of H2 was produced. The highest apparent quantum yield of the system was 55.3% at monochromatic 420 nm light. Photocurrent responses, UV–vis diffuse reflectance absorption spectroscopy, electrochemical impedance spectroscopy and photoluminescence (PL) spectroscopy were used to explain the mechanistic roles of CoSe and ZnSe in current photocatalytic system. This work showcased the successful usage of CoSe as cocatalyst and ZnSe as visible light active semiconductor for inexpensive conversion of solar energy to H2.

Objectives: To determine the preferred learning styles of Dental students and Dentists among various dental colleges using the VARK questionnaire. Study Design: Cross-sectional study. Setting: Various Dental Colleges in Karachi & Rawalpindi using the VARK questionnaire. Period: From June 2018 to February 2019. Material & Methods: Students, house-officers and demonstrators of dental medical college and hospital were asked to fill the VARK questionnaire which consists of 16 items. Four modes of learning either uni modal, bimodal or trimodal could be identified. The four modes include: visual, aural, reading, kinesthic. Results: Kinesthetic mode of learning was used by 24.5% individuals. Aural mode of learning was used by 25.3% individuals. Visual mode of learning was used by 15.5% individuals. Learning by reading was used by 17.7% individuals. Learning by using all modes was used by 1.5% individuals. Conclusion: Identifying the effective modes of learning is the first step towards changing the teaching strategy. Training in medicine and dentistry require innovative teaching ideas incorporating all modes for efficient learning of doctors.

BACKGROUND Effectiveness of scaling and root planing (SRP) with/without adjunct probiotic (Lactobacillus reuteri) treatment towards the reduction in periodontal inflammatory parameters (clinical attachment loss [AL], marginal bone loss [MBL], plaque index [PI], and bleeding on probing [BOP] in shamma users and non-users [controls] with chronic periodontitis [CP]) remains uninvestigated. The aim of the present randomized controlled trial was to compare the efficacy of SRP with and without adjunct probiotic therapy (PT) in the treatment of CP among shamma users and controls (individuals not using tobacco in any form). METHODS The study was conducted in accordance with the Consolidated Standards of Reporting Trials guidelines. Patient demographics were recorded using a questionnaire. Therapeutically, patients were allotted into four groups as follows: 1) group 1: Shamma chewers that underwent SRP alone; 2) group 2: Shamma-chewers that underwent SRP + PT; 3) group 3: Non-chewers that underwent SRP alone; and 4) group 4: Non-chewers that underwent SRP + PT. Periodontal parameters (PI, BOP, PD, clinical AL and mesial and distal MBL) were measured on all teeth except third molars at baseline and at 3- and 6-month follow-ups. Level of significance was set at P

Objective: Adenoid cystic carcinoma and polymorphous adenocarcinoma are primarily the tumor of minor salivary glands. Both show certain morphological similarities, which limit their proper diagnosis in settings where there are obscuring factors and limited biopsy material. However, there is a considerable difference in treatment and prognosis, which raises the need to distinguish these two entities. In this study, we discuss the utility of two immunohistochemical stains, p63 and p40, in different combinations for distinguishing polymorphous adenocarcinoma from adenoid cystic carcinoma. Materials and Methods: Two immunohistochemical stains, p63 and p40, were performed on 47 cases of adenoid cystic carcinoma and 23 cases of polymorphous adenocarcinoma. Results: 36 out of 47 cases of adenoid cystic carcinoma showed p63+ve/p40+ve immunoprofile, followed by p63-ve/p40-ve immunoprofile, which is seen in10 cases of adenoid cystic carcinoma. However, 22 out of 23 cases of polymorphous adenocarcinoma displayed p63+ve/ p40-ve immunoprofile. p63-ve/p40+ve is the least frequent observed immunoprofile, which is seen in only one case of adenoid cystic carcinoma. Conclusion: On combining all possible immunoprofile combinations, p63+ve/p40-ve immunoprofile appears to be the most sensitive profile for distinguishing polymorphous adenocarcinoma from adenoid cystic carcinoma.

Background To evaluate the influence of photodynamic therapy (PDT) and light activated irrigation (LAI) using different laser prototypes Er,Cr:YSGG (ECYL), Er:Yag (EYL), Nd-Yag (NYL) on pushout bond strength of Pre-fabricated fiber reinforced composite (PFRC) post to radicular dentin. Material and method Fifty maxillary and mandibular teeth were collected, cleaned and decoronated. Canals were instrumented using crown-down technique. Flaring of canals was performed using protaper S1, SX files. F1, F2 and F3 files were utilized for finishing of canal preparations. Prepared root canals were dried and obturated with gutta percha. Teeth were placed vertically within the section of polyvinyl pipes using acrylic resin. Post space preparation was completed using peso-reamers. Based on the PDT and laser activated irrigation (LAI) with different laser prototypes, samples were divided into five groups of 10 specimens each. Group 1- PDT, group 2–5.25 % NaOCl (sodium hypochlorite) and 17 % EDTA (ethylene diamine tetra acetic acid), group 3–5.25 % NaOCl with 17 % EDTA and NYL, group 4–5.25 % NaOCl with 17 % EDTA and EYL ; and group 5–5.25 % NaOCl +17 % EDTA and ECYL. Fiber post were luted in root canals with self-etch dual cure cement and teeth were sectioned at three levels (apical, middle and coronal). Push-out test was performed by placing the specimens in universal testing machine. Failure analysis of debonded surfaces was evaluated using stereomicroscope at 40× magnification. Means and standard deviations of push out bond strength were assessed by one-way analysis of variance (ANOVA). Comparison between means of push out bond strength was evaluated using Tukey multiple comparison tests (p = 0.05). Result The highest push out bond strength was observed in group 5 at all three levels, coronal (10.08 ± 0.74 MPa), middle (8.95 ± 0.94 MPa) and apical (6.00 ± 0.88 MPa). The lowest push out bond strength was demonstrated by group 2 at all levels, coronal (6.15 ± 1.22 MPa), middle (5.65 ± 0.95 MPa) and apical (2.25 ± 0.55 MPa). Intra-group comparison showed decrease in push out bond strength in the coronal to apical direction among all investigated groups. Inter-group comparison exhibited comparable push out bond strength at all three levels of root for group 1 and group 2 specimens (p > 0.05). Conclusion LAI with different laser prototypes improved push out bond values of PFRC post to root dentin as an adjunct to NaOCl and EDTA treatment. PDT improved push out strength compared to conventional canal cleaning regime.

Objective: The aim of this study was to evaluate factors affecting oral health related quality of life (OHRQoL) of patients using removable dental prosthesis. Methods: The present study employed a cross sectional analytical design. A total of 200 patients participated and interviewed using a cross sectional analytical design. In the first section of the questionnaire patients were asked about demographic data whereas the second part of the questionnaire assessed medical history, oral habits, smoking status, oral hygiene habits and frequency of dental visit. The questionnaire also collected information regarding patient’s removable prosthesis. Questionnaire of OHIP-DENT (Oral Health Impact Profile) was also employed to measure oral health quality of life (OHRQoL) on the domains of functional limitation (FL), physical pain (P1), psychological discomfort (P2), physical disability (D1), psychological disability (D2), social disability (D3) and handicap (H). Relationships between the demographic, socio-economic and education variables and others OHIP-EDENT scores were explored by comparing mean scores by applying ANOVA Results: The study participants comprised of 107 males (53.5%) and 93 females (46.5%). Regarding oral care, participants reporting to visit their dentist within one year were 40.0%. The highest score was recorded for the functional limitation (FL) domain (15.62±6.6), followed by social disability (D3) (15.23±5.06) and physical pain (P1) (14.28±4.8). The respective scores for physical (D1) and psychological disability (D2) and handicap (H) were 10.47±4.84, 11.32±5.38 and 12.45±4.50 respectively. Conclusions: Removable partial denture patients showed minimum problems with mastication, social compromise and functional discomfort. The oral health quality of life of removable denture patients is significantly influenced by patient education level, socio-economic status, medical conditions, smoking and tobacco use habits. doi: https://doi.org/10.12669/pjms.36.2.1257 How to cite this:Al-Deeb M, Abduljabbar T, Vohra F, Zafar MS, Hussain M. Assessment of factors influencing oral health-related quality of life (OHRQoL) of patients with removable dental prosthesis. Pak J Med Sci. 2020;36(2):213-218. doi: https://doi.org/10.12669/pjms.36.2.1257 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Background Studies assessing clinical and radiographic peri-implant parameters around short dental implants (SDIs) in treated generalized aggressive periodontitis (GAgP) patients are scant. Objectives This 3-year follow-up study aimed to compare the clinical peri-implant and radiographic bone status around SDIs placed in partially edentulous patients treated for GAgP and periodontally healthy patients and to assess the implant success rate between both the groups. Materials and methods A total of seven patients clinically diagnosed with GAgP and seven periodontally healthy patients was included in the clinical study. Forty-eight (29 maxilla; 19 mandible) and 11 (8 maxilla; 3 mandible) SDIs were placed in the GAgP group and healthy group, respectively. Plaque index (PI), bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL) were recorded at six sites around all teeth and implants. Marginal bone loss (MBL) was studied incorporating in a specialized software and examined on a calibrated computer display screen with the help of an image analyzer. Patient satisfaction was recorded using a questionnaire sheet that contained questions regarding esthetics and function of the restorations. Results The implant survival rate after 3 years was 81.25%. BOP and CAL around SDIs of GAgP patients were significantly higher than in periodontally healthy subjects (P = .01) throughout the follow-up. CAL around the teeth of GAgP patients was significantly greater during the follow-up than around the teeth of periodontal healthy subjects (P = .02). The PI and BOP between the teeth and implants showed no statistical significant difference. The mean PD at teeth was 0.4 mm greater than at implants. Implants showed significantly increased attachment loss than teeth (P = .01). The overall mean satisfaction of visual analogue scale was 12.8 ± 1.45. Conclusion This short-term follow-up study indicates SDIs remain functionally stable in the posterior jaws of treated GAgP patients.

We describe two cases of inflammatory myofibroblastic tumor (IMT) involving genitourinary system. One patient with mass of urinary bladder presented with lower abdominal pain. Other presented with a mass involving right kidney presented with right flank pain. At time there are no specific guidelines exist for the management of inflammatory myofibroblastic tumors. In this case series we will discuss the work-up and management approaches done for each case. Continuous...

For the next generation applications in mobile communication, radar and satellite communication we need the devices that can operate at high frequencies and high power with minimum power consumption. There is a growing importance in the recent years for the development of GaN transistors.This paper presents design of the power efficient GaN based high power amplifier operating in the bandwidth of 5GHz – 7GHz based on a 12 Watt Discrete Power GaN on SiC HEMT from TriQuint. In this manuscript the design of RF power amplifier, its stability, input and output matching impedance and performance for 5-7GHz is presented. Design and simulations of the power amplifier are carried out using Advanced Design System (ADS). Simulation results of device stability, gain and Power Added Efficiency (PAE) shows good accordance with the specifications and parameters of the device.In the design process, for better correlation in measurement and simulation results precision of passive element models are specially considered. In 1 dB compression point for the designed high power amplifier, the experiment and the simulation results show a Power Efficiency of 68%.

Crankshaft is an important component of an engine with intricate geometry which converts the linear displacement of piston into rotary motion. Since the crankshaft is predisposed to massive loads during combustion cycles, so different factors like endurance has to be kept in mind while designing crankshaft. Keeping in view the above scenario, the main motive of this paper is to do the fatigue analysis so that we can analyze various factors that are affecting the service life of crankshaft.

Purpose: To review research contributions to performance measurement systems.Design/Methodology/Approach: Critical review of the literature using the systems developed by previous contributors: performance measurement systems; financial measures vs. non-financial measures; quantification of qualitative performance indicators; and generalization vs. specification in performance measurement system.Findings: The absence of unified performance measurement systems means that the existing literature is capturing a wide range of financial measures and qualitative specifications. As a result, performance measurement system appears scattered rather than summative. New measurement systems are needed for correct measurement of performance comprising both financial variables with non-financial variables and also inclusion of qualitative perspective is inevitable.Research Limitations/Implications: Similar researches have suggested performance measurement systems must always be tailored according to requirement of assessment entity. Empirical work must explain the measurement of performance explicitly.Originality/Value:This paper synthesizes the existing literature in the area of performance measurement systems that has been critical for the performance evaluator in terms of advice given to strategic manager, business owners and policy makers.