[en] The crack propagation mechanisms of γ-titanium aluminides with fully lamellar microstructure have been studied using in-situ deformation in the Atomic Force Microscope (AFM). AFM demonstrated the unique capability to detect elastic as well as plastic deformation during in-situ tests from topography changes on the surface. It was found that the crack nucleation, which can occur at γ/γ and α₂/γ interfaces as well as inside the γ-phase, is always preceded by strong local elastic deformation. No cracking inside the α₂-phase was observed. The elastic and plastic deformation was confined inside the γ-phase and especially pronounced near interfaces which can be explained by the differences of the elastic and plastic deformation behavior of the γ- and α₂- phase.

[en] In this paper paper, we explore tile linear estimator (LE) for the parameters of ARCH of ARCH models. The accuracy of LE ill terms of estimation and volatility forecasting is compared with the well-known quasi- Maximum likelihood estimator (QMLE). Monte Carlo simulations are used to check the relative performance of both estimators. Our study indicates that the linear estimator provides accurate estimates for the parameters of ARCH models and also predicts volatility better than the QMLE in most of the cases. Application to real data sets is also presented. (author)

[en] Objective: To compare the result of the combination of hyperbaric bupivacaine plus fentanyl with hyperbaric bupivacaine alone in patients undergoing caesarean section in spinal anaesthesia. Study Design: Comparative, cross-sectional study. Place and Duration of Study: Department of Anesthesia, Fauji Foundation Hospital, Rawalpindi Pakistan, from Dec 2017 to Jun 2018. Methodology: After consulting the institutional ethical review committees a total of 60 females between ages 18-40 years were enrolled for caesarean section delivery. They were divided into two groups. The study group (n=30) received a subarachnoid injection of 0.5% hyperbaric bupivacaine (10mg) 2ml with 25ug of fentanyl 0.5ml and control group (n=30) was injected 0.5% hyperbaric bupivacaine 12.5mg (2.5 ml) only. Pain experienced during the procedure was assessed by using 10-point visual analogue scoring method. The mean duration of analgesia, mean arterial blood pressure and heart rate after surgery were compared between two groups. Results: The mean duration of analgesia was 206.5/min ± 6.4 in the study group and it was 163.6min ± 7.2 in the control group (p=0.001). Mean arterial BP after surgery was 92.3mmHg ± 3.8 in the study group and 88.7mmHg ± 4.1 in the control group (p=0.001). The mean heart rate recorded after surgery was 75.2/min ± 5.2 in the study group and it was 70.4/min ± 6.1 in the control group (p=0.001). Conclusions: The mean duration of analgesia was significantly longer in the study group when compared with the control group with better mean arterial blood pressure and heart rate response after Caesarean section. (author)

[en] Objective: To find the prevalence of Hepatitis C in patients on maintenance haemodialysis. Results: Sixty-eight percent of the patients on maintenance haemodialysis were found to be positive for anti HCV antibody. Prevalence in normal individuals was 10 percent and relative risk for the patients on maintenance haemodialysis were 6.8. Conclusion: hepatitis-C is endemic among patients on maintenance haemodialysis and prevalence is much higher in developing countries as compared to developed world. (author)

[en] Background: For the growth and development of the unborn child, amniotic fluid is absolutely necessary. Strong interactions between the fetus, placenta, and parts of the mother are given their volume1. Oligohydramnios is defined as having an amniotic fluid index (AFI) <5th percentile or AFI 5 cm during pregnancy and no water at a depth of 23 cm before the cornea. This is a common problem that occurs in 35% of pregnancies during childbirth2. Aim: To determining the correlation between oligohydramnios in pregnant women who are late in pregnancy (3rd trimester) and adverse birth outcomes such as partial surgery, decreased Apgar score, and lower birth weight. Study design: Cohort study Study set up: Obstetrics and Gynecology Department, Fatima Memorial Hospital Lahore. Study period: six months starting 15-01-2022 to 14-07-2022 Methods: 242 females were enrolled. Two groups of participants were created: group II had normal AFI and group I had oligohydramnios. Females given intra venous fluids to group I after ruling out any contra indication. The perinatal result was then documented. SPSS version 20 was used to enter and evaluate all of the gathered data. Results: In exposed group the mean age was 27.79±6.72 years, whereas in unexposed group the mean age was 28.25±6.77 years. The C-section was done in 124(51.2%) females. RR = 0.693 [1.25-3.49] While the Low Birth Weight and poor APGAR score has shown protective effect. Practical implication: Oligohydramniosmeans decreased amniotic fluid around the fetus. There is deficiency of amniotic fluid < 200 ml at a time. Approximately 8-10% of pregnant ladies may have decreased level of amniotic fluid but 5% have been confirmed diagnosis of oligohydramnios. Conclusion: So complications of surgery are directly related to the severity of oligohydramnios in pregnant women while low birth weight and poor APGAR scores has shown protective effect in women presented in last trimester of pregnancy. (author)

[en] Objective: This study was carried out to determine the frequency, etiological factors, modes of presentation, accuracy of diagnostic modalities, operative findings and surgical treatment of tubal pregnancies. Design: Observational study. Place and duration of study: This study was conducted in gynae unit iii, Sir Ganga Ram Hospital, Lahore from January 1995 to December 1996. Subject and Methods: All the patients diagnosed as a case of tubal pregnancy in two years period were included in the study. Detailed history regarding the symptoms and risk factors of tubal pregnancy was taken followed by clinical examination. The diagnostic and treatment modality used and operative findings were also recorded. All the data was recorded on a proforma and finally the results were analysed. Results: Incidence of tubal pregnancy was found out to be 1:305 deliveries. Out of these, 70% of the cases occurred in the age group of 21-30 years and in patients with low parity (in para 0-2) 65% of the patients had high risk factor e.g previous abdominopelvic surgery PID or history of infertility. Pain was the commonest symptom (90% of cases) followed by vaginal bleeding (80%) adnexal masses (70%) and amenorrhea (65%). Acute tubal pregnancy was found in 85% of the cases while 15% of cases had chronic tubal pregnancy. Tubal pregnancy in the ampullary region was detected in 65% patients. Conclusion: Previous abdominopelvic surgery, PID or history of infertility and use of intra-uterine contraceptive device are the main etiologic factors. Most of the patients present at a very late stage with ruptured tubal pregnancy followed by salpingostomy in 95% of cases. Only 5% of cases had conservative surgical treatment i.e salpingostomy. Culdocentesis ultrasonography and laparoscopy were good diagnostic modalities. (author)

[en] Objective: To evaluate the current trend of antimicrobial susceptibility pattern of Salmonella typhi and paratyphi. Methodology: This observational laboratory based study was conducted at Department of Microbiology, Khawaja Muhammad Safdar Medical College, Sialkot from January 1, to June 30, 2019. Blood culture samples were collected aseptically, sub cultured and identified as Samonella typhi or paratyphi A, as recommended by clinical laboratory standard institute. Results: A total of 2773 samples were collected, among these 1945(70%) were from neonates and were excluded from the study. Among rest 828(30%) blood culture samples, 55(6.64%) yielded growth of Salmonella typhi and paratyphi. Out of total Salmonella species, 44(80%) were Salmonella typhi and 11(20%) were Salmonella Paratyphi A. Multidrug resistant salmonella were 47% and extensively drug resistant salmonella were 16%. Meropenem and azithromycin showed 100% sensitivity while ceftriaxone in 84% cases. Conclusion: Trends of antibiotic susceptibility are changing as flouroquinolones are less effective than first line drugs. Extensively drug resistant cases of typhoid are also detected, which needs regular monitoring of sensitivity pattern. (author)

[en] Subgrade is a most important part of a pavement structure, which should have a reasonable stiffness modulus and shear strength. CBR (California Bearing Ratio) test is performed to evaluate stiffness modulus and shear strength of subgrade soils. However, CBR test is laborious and time consuming, particularly when soil is highly plastic like Jamshoro soil. In order to overcome this limitation, it may be appropriate to correlate CBR value of soil with its index properties like grain size analysis, Atterberg limits, and compaction characteristics such as MDD (Maximum Dry Density) and OMC (Optimum Moisture Content). This paper expresses the correlations between CBR value of Jamshoro soil and its index properties. SLRA (Single Linear Regression Analysis) and MLRA(Multiple Linear Regression) based Models were utilized. It is seen that MLRA gave better correlations up to R2 of about 0.984. It is observed that the Soaked CBR value can be predicted with confidence from LL (Liquid Limit), PI (Plasticity Index) and percent finer while the un-soaked CBR value can be obtained from LL, plasticity index and MDD. (author)

[en] Objective: To assess the beneficial effect of intravenous pamidronate treatment in children with osteogenesis imperfecta (OI). Study Design: Experimental study. Place and Duration of Study: Endocrine Unit at the National Institute of Child Health, Karachi, Pakistan, from January 2007 to December 2011. Methodology: All children diagnosed with osteogenesis imperfecta on the basis of repeated spontaneous fractures and typical radiological findings registered during the study period, were included in this study. Pamidronate therapy were offered to those with more than 3 fractures per year or had platyspondyly. Pamidronate disodium was diluted in isotonic saline and administered by slow ravenous infusion over 3 hours in a dosage 1 mg/kg/day for 3 consecutive days 3 monthly for 2 years. Fracture rate, bone mineral density (BMD), mobility score, wellbeing and pain episodes were evaluated at baseline and 2 years after the treatment. Good response was defined as less than 2 fractures per year or mobility score improvement and poor response as more than 2 fracture per year with mobility score less than 2. Results: Seventy two patients were included in this study. There were 40 boys and 32 girls with mean age of 3.64 +- 3.2 years. The annual fracture rate decreased overall from 5.8 +- 1.61 to 0.6 +- 0.93 (p < 0.001). BMD Z-score improved from -5.3 +- 1.74 to -1.7 +- 0.72 (p < 0.001). Mobility score was 0.94 +- 1.30 at baseline and 2.5 +- 1.02 at the end of the treatment (p < 0.001). Wellbeing gained from 3.63 +- 1.44 to 7.8 +- 1.18 (p < 0.001) and pain episode improved from 24.1 +- 8.15 to 2.7 +- 8.31 (p < 0.001). Good response was noted in 92% of patients and poor response in 8% patients. Conclusion: Bisphosphonate seems to be an effective symptomatic treatment for children with osteogenesis imperfecta irrespective of severity of mutation or clinical phenotype. Cyclical bisphosphonate therapy has a positive effect on fracture rate, BMD, mobility score, wellbeing and pain episode. (author)

[en] Aim: To determine the success of bipolar hemiarthroplasty in patients with fracture neck of femur. Study Design: Descriptive Case series. Setting: Department of Orthopaedics and Spinal Surgery, Ghurki Trust Teaching Hospital/Lahore Medical & Dental College, Lahore from 3rd August 2011 to 4th August 2012. Methodology: Fifty patients with fracture neck of femur treated with bipolar hemiarthroplasty were included. Investigations like X-rays pelvis with both hips were carried out. Epidural or spinal anaesthesia was used. Modified Hardinge direct lateral approach and supine position was used for bipolar prosthesis. Postoperatively all patients were mobilized with full weight-bearing after 24 to 48 hours with assistance from physiotherapist and intravenous antibiotic continued for 48-72 hours followed by orally till wound healed. Results: There were 20 males and 30 females with male to female ratio 1:1.5. The mean±SD between the ages was 63.36±7.27 years. The success rate was 37 (74%) and 13 (26%) was not successful. Conclusion: Bipolar hemiarthroplasty is safe and effective treatment modality in patients with femur neck fractures especially in older age patients. (author)