Design and characterization simulation of Ti: sapphire-based femtosecond laser system using Lab2 tools in the NI LabView

We report on the 825-nm center wavelength, 9.17 mJ pulse energy Ti:sapphire-based femtosecond laser system simulation carried out by Lab2 tools in LabVIEW (National Instruments, Inc.). The design investigation and characterization of stretched, amplified and compressed pulses made by intensity module and second harmonic generation (SHG) frequency-resolved optical gating (FROG) module in Lab2. The minimum pulse duration of ~37.80 fs at the output of the compressor end obtained by simulations. The variation of pulse energy, FWHM and central wavelength versus number of passes in the amplifier are computed. The lab2 tools help to design and characterize laser system before to set up on the optical table. The simulation results save time to calculate parameters which are essential in femtosecond laser system designing. The Lab2 simulation tools, along with financial constraints, it is easier, simple and efficient to obtain results in short time

Water-Nutrient-food Nexus The Role of Green Algae for Sustainable Food Production in Urban Wetlands Through Untreated Wastewater

The nutrients in domestic wastewater are increasingly being regarded as a valuable resource for energy and nutrient recovery for an Eco-city. The nutrient stream can be used safely for food production through ecological engineering interventions (introduction of green algae in urban wetlands). Effects of wastewater on growth yield and microbial contamination on hydroponic tomato (Lycopersicon esculentum) was studied in pilot scale wetland for 6 month under the presence of green algae (Euglena sp.) with different chlorophyll a concentration. Domestic wastewater (BOD 205 mg.L-1, TN 29 mg.L-1 and TP 8 mg.L-1) with loading rate of 0.9 L.m-2.d-1 was used for each wetland. The wastewater did not affect fruit pH, increased their size up to 1.7 ± 0.31 cm in diameter, and weight up to 69.3 ± 6.0 g. Microbial contamination (Total coliforms (TC) and Fecal coliforms (FC)) on fruit surface significantly decreased (p < 0.05) with the increasing algal concentration up to 240 μg.L-1. Inactivation of bacterial contamination (TC and FC) under the presence of algae associated with high dissolved oxygen concentration (9.7 ± 1.1 mg.L-1) and pH increases (8.2 ± 0.8) attributes in wetland. In summary, tomato production in urban wetlands under the presence of green algae enhances the importance of safe and sustainable food production through untreated wastewater

Passive immunization against highly pathogenic Avian Influenza Virus (AIV) strain H7N3 with antiserum generated from viral polypeptides protect poultry birds from lethal viral infection

Our studies were aimed at developing a vaccination strategy that could provide protection against highly pathogenic avian influenza virus (AIV), H7N3 or its variants outbreaks. A purified viral stock of highly pathogenic H7N3 isolate was lysed to isolate viral proteins by electrophresing on 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), followed by their elution from gel through trituration in phosphate buffered saline (PBS). Overall, five isolated viral polypeptides/proteins upon characterization were used to prepare hyperimmune monovalent serum against respective polypeptides independently and a mixture of all five in poultry birds, and specificity confirmation of each antiserum through dot blot and Western blotting. Antiserum generated from various group birds was pooled and evaluated in 2-week old broiler chicken, for its protection against viral challenge. To evaluate in-vivo protection of each antiserum against viral challenges, six groups of 2-week old broiler chicken were injected with antiserum and a seventh control group received normal saline. Each group was exposed to purified highly pathogenic AIV H7N3 strain at a dose 105 embryo lethal dose (ELD50). We observed that nucleoprotein (NP) antiserum significantly protected birds from viral infection induced morbidity, mortality and lowered viral shedding compared with antiserum from individual viral proteins or mixed polypeptides/proteins inclusive of NP component. The capability of individual viral polypeptide specific antisera to protect against viral challenges in decreasing order was nucleoprotein (NP) > hemagglutinin (HA) > neuraminidase (NA) > viral proteins mix > viral polymerase (PM) > non-structural proteins (NS). Our data provide proof of concept for potential utilization of passive immunization in protecting poultry industry during infection outbreaks. Furthermore conserved nature of avian NP makes it an ideal candidate to produce antiserum protective against viral infection

Non-linear propagation effects of intense femtosecond pulses on low order harmonics in solids

The non-linear propagation of the intense near-infrared (NIR) driving field in wide bandgap materials pose a challenge and an opportunity to control the spectral properties of high harmonic generation (HHG) in solids. Here, we have investigated the non-linear propagation effects of the ultrafast intense near-infrared (NIR) driving field at 800 nm of 40 fs pulse duration operating at a repetition rate of 1 kHz focused on the wide bandgap dielectrics such as MgO, Chromium (Cr) doped MgO (Cr: MgO), Sapphire (Sa) crystals and fused silica (FS). Furthermore, we have generated second and third harmonic (TH) in these materials to explore the non-linear response at a strong field. To quantify the non-linear propagation effects, low-order harmonics have been generated in reflection and compared with the harmonics generated in transmission. We observe spectral shifts and broadening of the driving field spectrum which is imprinted on the harmonics. We attribute these effects to strong photoionization, generation of free-carrier density and self-phase modulation effects. We have also studied the polarization dependence of second harmonic generation (SHG) and TH in FS. The linear polarization dependence of below bandgap harmonics in FS and Sa generated in reflection demonstrated the sharp anisotropy than in transmission. This work shows the sensitivity to control the spectral profile of harmonics by manipulating the driving field, showing the possibility of new tailored solid-state XUV sources for optical diagnostics

Anosmia in Parkinson’s Disease in Pakistan: A Matched Case – Control Study

Objective:  To assess olfactory dysfunction in Parkinson's disease (PD) patients in Pakistan utilizing an autochthonous smell test. Setting:  Tertiary care center, single-center study. Materials and Methods:  Eighty-seven non-demented patients with PD, who fulfilled Queen Square Brain Bank Criteria were enrolled at the Movement Disorder Clinic, Lahore General Hospital (LGH), Lahore. Fifty-eight controls matched by gender, age, and place of residence were enrolled among patients and visitors attending other hospital clinics. Both groups underwent olfactory testing using the Pakistani Smell Identification test (PKSIT). The participants were required to identify the smell from a set of choices and were scored out of 10. Results:  Among patients in the study group, the mean duration of disease was 4.7 years (range 6 months to 19 years). The PD onset mean age was 52.15 ± 13.02 years among patients. The mean number of smell test items accurately recognized by the PD patients was 4.55 ± 2.4. A multiple linear regression demonstrated that age (P < 0.05) but not disease duration (P = 0.899) was a significant determinant of the smell test result in PD and control groups. The mean number of smell test items appropriately recognized by the controls was 7.33 ± 1.69. Logistic regression showed that the PKSIT had 73.2% sensitivity and 84.3% specificity to distinguish PD from control. Conclusion:  PKSIT being easily available, cheap, and more convenient to use in the Pakistani population, can be used in the evaluation of olfactory dysfunction in PD subjects

Successful Surgical Resection of Advanced Gastrointestinal Stromal Tumor Post Neoadjuvent Therapy

We report a case of a 48-year-old Indian male who presented with swelling and firmness in his left upper part of the abdomen of one month duration with anorexia and weight loss. Initial examination revealed an intra abdominal mass of around 16.8x11.0x24.5cm with minimal left sided pleural effusion. A biopsy from the mass confirmed the diagnosis of gastrointestinal stromal tumour (GISTs) as supported by immmunohistochemistry results which showed strong positivity for c-kit while stains for smooth muscle actin, desmin, myoglobin, S100 Protein and cytokerstin remained negative. The patient was not suitable for surgical intervention in view of advanced tumor, and Imatinib Mesylate 400mg daily was started with the aim of making the tumor operable. Such therapy lasted for twenty months and was tolerated well by the patient. It then resulted in gradual tumor regression, following which the patient underwent successful tumor resection. Post surgical resection patient had no radiological evidence of intra abdominal tumor but mild left sided pleural effusion with left lower lobe atelectasis. The patient had uneventful post operative recovery and he is currently on Imatinib mesylate and tolerating treatment well with mild skin rash. The experience with preoperative imatinib on surgical resection rates and post operative outcomes is limited especially with primary locally advanced GISTs. In our case successful surgical resection was possible for a huge locally advanced GIST with unusually prolonged treatment of twenty months with imatinib preoperatively

Frequency of Elevated Mean Platelet Volume in Patients with Different Severities of Acute Ischemic Stroke

Objective: Determine the frequency of elevated mean platelet volume in patients with different severities of acute ischemic stroke who presented in Lahore general hospital Lahore.Study Design: Cross sectional survey.Duration: Study duration was 1year.Sample Size: 130 patients of acute ischemic stroke.Sample Technique: Non-probability purposive sampling.Methodology: Consecutive 130 patients of acute ischemic stroke presented to emergency department or admitted through OPD within 24 hours of onset of symptoms and fulfilling the inclusion criteria were selected. Patients were divided in two groups based on mRS scoring. MPV was measured by automated hematology analyser Sysmex KX-21. The severity of stroke was assessed by Modified Rankin Score (mRS) between 24 to 72 hours of onset of symptoms.Patients with acute ischemic stroke proved by CT brain presenting within 24 hours of symptom onset and Age 40 and above and both genders were include. Patients with hematological malignancies were excluded from study.Data Collection: 130 patients admitted patients (through emergency and outdoor), Lahore General Hospital, Lahore fulfilling the inclusion criteria were selected for study.The severity of stroke was assessed by modified Rankin Scoring (mRS). The patients were divided in to two groups based on mRS scoring. Mean platelet volume and mRS score were recorded. Major risk factors like hypertension, diabetes mellitus, smoking history and hypercholesterolemia if present were also recorded. The demographic information of these cases like name, age, sex and address recorded. The collected information was entered into SPSS version 11.0. Quantitative variables like age, mean platelet volume were analyzed as mean and standard deviation. Frequencies of elevated MPV in both groups were described. Gender and severity of stroke (mild, moderate to severe) were analysed as frequency and percentage. Elevated MPV was also analysed as frequency and percentage in both groupsResults:  Among the enrolled 130 patients 80 (61.5%) were males and 50 (38.5%) were females (Table 1, Graph 1) with age ranging from 41 – 74 years with a mean age of 56.85 ± 10.15 years. 45 (35%) patients had modified Rankin scale (mRS) between 0 to 2 while 85 (65%) patients had mRS between 3 to 6. Overall mean platelet volume was found to be elevated in 85 patients. Among them 62 (73%) patients had mRS of 3 – 6 (group 2) while 23 patients had mRS of 0 – 2 (group 1). Among the 45 (23%) patients who had normal mean platelet volume, 22 belonged to group 1 (mRS 0 – 2) while 23 were in group 2 (mRS 3 – 6).Conclusion: MPV, with an easy way of measurement, may be anearly and important predictor for the prognosis of ischemic stroke

Degradation assessment of nuclear power plant extraction steam piping after long term service

Degradation due to ageing in a Nuclear Power Plant’s Extraction Steam Piping has been assessed. Samples of twelve years old seamless carbon steel SA 106B pipe have been taken and subjected to metallographic examination, hardness testing, radiographic examination and ultrasonic thickness measurement to investigate and analyze ageing in piping material. Metallographic examination of aged sample revealed irregularly distributed graphite nodules in ferrite grains and on grain boundaries as well, the reduction in pearlite phase has also been observed from 40% to 25%. This Transformation in microstructure has reduced hardness of steel. Reduction in hardness has found 20.4% and 0.7% on inner and outer layer of the pipe material respectively. Corrosion pits having average depth of 0.07 mm have been found on external surface. Radiograph of aged pipe revealed material removal and wall thinning due to erosion on inner surface of pipe. The extent of erosion had been checked, which has found 8.7%