Temperature Dependent Piezoelectric Properties of Lead-Free (1-x)K0.6Na0.4NbO3–xBiFeO3 Ceramics

(1-x)K0.4Na0.6NbO3–xBiFeO3 lead-free piezoelectric ceramics were successfully prepared in a single perovskite phase using the conventional solid-state synthesis. Relative permittivity (εr) as a function of temperature indicated that small additions of BiFeO3 not only broadened and lowered the cubic to tetragonal phase transition (TC) but also shifted the tetragonal to orthorhombic phase transition (TO–T) toward room temperature (RT). Ceramics with x = 1 mol.% showed optimum properties with small and large signal piezoelectric coefficient, d33 = 182 pC/N and d∗33 = 250 pm/V, respectively, electromechanical coupling coefficient, kp = 50%, and TC = 355°C. kp varied by ∼5% from RT to 90°C, while d∗33 showed a variation of ∼15% from RT to 75°C, indicating that piezoelectric properties were stable with temperature in the orthorhombic phase field. However, above the onset of TO–T, the properties monotonically degraded in the tetragonal phase field as TC was approached

Cytokine genes as potential biomarkers for muscle weakness in OPMD

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Phase and microstructural analysis of NdTi0.8M0.2O3.4 (M = Al, Ga) microwave ceramics

In this paper, we report the characterization of NdTi0.8M0.2O3.4 (M = Ga, Al) ceramics prepared via mixedoxide solid state sintering route. X-ray diffraction analysis of the samples revealed the formation of singlephase for NdTi0.8Ga0.2O3.4 sample while secondary phase was formed in the case of NdTi0.8Al0.2O3.4.Microstructural analysis of the sample showed dense packed grains. NdTi0.8M0.2O3.4 with M = Ga and Alexhibited a dielectric constant (r) = 34, quality factor (Q×f) = 9,776 and 10,867 GHz and temperaturecoefficient of resonance frequency (τf) = -113 and -90 ppm/oC, respectively. Further work is required ontuning the low τf of the samples for possible applications in the GHz frequency range.Keywords: Ceramics; ABO3.4, Perovskites, Microwave dielectric properties

Clinical Presentation and Surgical Management of Brain Abscess

Objectives:  To determine the clinical presentation, surgical management and outcome of patients with Brain Abscess in our locality. Study Design:  Descriptive study. Place and Duration of Study:  Bolan Medical complex, Sandeman Provincial Hospital and Akram Hospital, Quetta. Duration from January 2003 to July 2004. Subject and Methods:  Study conducted on twenty patients with Brain Abscess confirmed on CT Scans. Patients of both gender and all age group were included in the study. Those managed conservatively were excluded from the study. Results:  Surgery was performed on all patients with the mortality rate of 20% (4) in this study. Conclusion:  Appropriate microbial coverage and surgical management of Brain Abscess reduced the mortality and neurological deficits. Key Works:  Brain Abscess, Neurological deficit, Mortality

Management and Outcome of Compound Depressed Skull Fracture

Objectives:  To determine the clinical presentation, management and outcome of patients presenting with compound depressed skull fracture. Study Design:  Descriptive study. Place and Duration of Study:  Bolan Medical Complex Hospital Duration from May 2003 to March 2006. Materials and Methods:  Study conducted on sixty patients with compound depressed skull fracture. Patients of both gender and all age group were included in the study, those with major life threatening injuries to other organs were excluded. Results:  Out of total of 60 patients, 42 (70%) patients were male and 18 (30%) were female. Majority were in the first (33%) second (25%) decade of life (child and young patients). Most of patients were injured as a result of road traffic accidents 32 (53%), fall from height in 16 patients (27%) and assault in 12 (20%). Seventy percent of patients in fall group fell from roof while 30% from electric pool. Patients presented with various signs and symptoms like headache, vomiting (70%), loss of consciousness (33%), ear, nose and throat bleed (40%), CSF rhinorrhea (17%) and fits. Seventy percent of patients in this study presented with sings of raised intracranial pressure. Temporal region was the most frequently affected area in 30 (50%) cases.  Conclusion:  Children and yuoung adults and males are most commonly affected. Road traffic accidents and falls from height are the most common modes of head injury. If treated properly most cases of compound depressed fracture will reveal good results. &nbsp

Efficacy of Conservative Management with Anti Tuberculosis Treatment in Patients with Spinal Tuberculosis

Introduction: Spinal TB is a result of haematogenous dissemination from primary focus in lungs or lymph nodes. Most of the under developed and developing world is endemic with TB as these populations are poorly nourished, overcrowded and live in sub standard social conditions and TB being an infectious disease spreads and sustains well in these overcrowded settings. Spinal TB is a common pathology in developing countries like Pakistan. We present a cohort study on findings of conservative treatment in patients suffering from spinal TB.Objective: To determine the efficacy of conservative treatment (ATT) in TB spine.Material and Methods: A cohort study was conducted in Bolan Medical Complex, Quetta in a period of 4 years from 2009 to 2013. A total of 135 cases of spinal tuberculosis were selected. Patients with cervical and cranio-cervical, and sacral TB were excluded from the study and also patients with any malignancy and other associated chronic joint conditions related to back were not selected. Patients were confirmed as a case of spinal TB using standard laboratory and radiology diagnostics. The patients were treated with ATT and followed up for 9 months until the completion of therapy.Results: The average age of patients was 48.8 years. Both male (50.4%) and female (49.6%) were equal in proportion in this study. Lumbar region was more affected (71.1%) with TB spine. Almost all study patients (99.3%) were cured with ATT whereas 1 (0.7%) patient was managed surgically.Conclusion: ATT is effective in the treatment of spinal tuberculosis provided timely diagnosis and initiation of therapy

Enhanced Thermal Stability in Dielectric Properties of NaNbO3 –Modified BaTiO3 –BiMg1/2 Ti1/2 O3 Ceramics for X9R-MLCC Applications

0.5BaTiO3 –(0.5 − x)BiMg1/2 Ti1/2 O3 –xNaNbO3 (x = 0.10–0.30) ceramics were processed via a conventional solid state sintering route. X-ray diffraction analysis and Raman spectroscopy showed the formation of a cubic perovskite structure. Microstructural analysis of the samples revealed densely packed grains. The addition of NaNbO3 resulted in the enhancement in dielectric properties as a function of temperature. Relative permittivity decreased from 850 to 564 (at room temperature) with an increase in x; however, the stability in dielectric properties was improved with an increase in NaNbO3 concentration. At x = 0.25, relative permittivity (εr ) was ~630 ± 15% in a temperature range of −70–220◦ C with low dielectric loss (tan δ) < 0.025 (−57 to 350◦ C) and high recoverable energy density ~0.55 J/cm3 which meet the criterion for X9R MLCC applications.Fil: Muhammad, Raz. Abdul Wali Khan University Mardan; PakistánFil: Ali, Asif. Abdul Wali Khan University Mardan; PakistánFil: Camargo, Javier Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Castro, Miriam Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Lei, Wen. Wenzhou Advanced Manufacturing Technology Research Ins; ChinaFil: Song, Kaixin. Hangzhou Dianzi University; ChinaFil: Wang, Dawei. Shenzhen Institute Of Advanced Electronic Materials; Chin

Impact of Time Taken on the Surgical Outcome of Epidural Hematoma in Patients with Road Traffic Accidents

Introduction: Traumatic epidural hematoma is a neurosurgical emergency and timely surgical intervention is the standard treatment. The rationale of this study is to highlight the importance of time of surgery on the surgical outcome of epidural hematoma particularly in patients with history of road traffic accidents.Objectives: To determine the impact of time taken on the surgical outcome of epidural hematoma in patients with road traffic accidents.Study Design: Descriptive Case Series.Place and Duration of Study: Bolan Medical Complex Hospital and Sandeman Provincial Hospital, Quetta. From April 2010 to July 2011.Patients and Methods: Sixty adult patients of either gender with H/O road traffic accident with epidural hematoma on axial images of CT scan brain were included. All patients were allocated into three groups with 20 patients in each group. Patients in group I were those in whom time from the occurrence of trauma to the surgical evacuation of hematoma was &lt; 1 hour, 1 to 6 hours in group II and &gt; 6 hours in group III.Results: In group I, 18 (90%) showed favorable and 2 (10%) showed unfavorable outcome. In group II, 14 (70%) showed favorable and 06 (30%) showed unfavorable outcome. In group III, 10 (50%) showed favorable and 10 (50%) showed unfavorable outcome. Significant association was found between outcome and time of surgery (P &lt; 0.05).Conclusions: Frequency of favorable outcome after surgical evacuation was significantly higher in patients in whom surgery was performed within one hour after the trauma