The Atmospheric Lifetime Experiment and the Global Atmospheric Gas Experiment (ALE/GAGE)

The ALE/GAGE project was designed to determine the global atmospheric lifetimes of the chlorofluorocarbons CCl3F and CCl2F2 (F-11 and F-12), which had been identified as the main gases that cause stratospheric ozone depletion. The experimental procedures also provided the concentrations of CH3CCl3, CCl4 and N2O. The extended role of the project was to evaluate the mass balances of these gases as well. Methylchloroform (CH3CCl3) serves as a tracer of average atmospheric OH concentrations and hence the oxidizing capacity of the atmosphere. Nitrous oxide (N2O) is a potent greenhouse gas and can also deplete the ozone layer. Measurements of these gases were taken with optimized instruments in the field at a frequency of about 1 sample/hr. Toward the end of the present project methane measurements were added to the program. The final report deals with the research of the Oregon Graduate Institute (OGI) as part of the ALE/GAGE program between 4/1/1988 and 1/31/1991. The report defines the scope of the OGI project, the approach, and the results

Emissions Of Greenhouse Gases From Rice Agriculture

This project produced detailed data on the processes that affect methane and nitrous oxide emissions from rice agriculture and their inter-relationships. It defines the shifting roles and potential future of these gases in causing global warming and the benefits and tradeoffs of reducing emissions. The major results include: 1). Mechanisms and Processes Leading to Methane Emissions are Delineated. Our experiments have tested the standard model of methane emissions from rice fields and found new results on the processes that control the flux. A mathematical mass balance model was used to unravel the production, oxidation and transport of methane from rice. The results suggested that when large amounts of organic matter are applied, the additional flux that is observed is due to both greater production and reduced oxidation of methane. 2). Methane Emissions From China Have Been Decreasing Over the Last Two Decades. We have calculated that methane emissions from rice fields have been falling in recent decades. This decrease is particularly large in China. While some of this is due to reduced area of rice agriculture, the bigger effect is from the reduction in the emission factor which is the annual amount of methane emitted per hectare of rice. The two most important changes that cause this decreasing emission from China are the reduced use of organic amendments which have been replaced by commercial nitrogen fertilizers, and the increased practice of intermittent flooding as greater demands are placed on water resources. 3). Global Methane Emissions Have Been Constant For More Than 20 Years. While the concentrations of methane in the atmosphere have been leveling off in recent years, our studies show that this is caused by a near constant total global source of methane for the last 20 years or more. This is probably because as some anthropogenic sources have increased, others, such as the rice agriculture source, have fallen. Changes in natural emissions appear small. 4). Nitrous Oxide Emissions From Rice Fields Increase as Methane Emissions Drop. Inundated conditions favor anaerobic methane production with high emission rates and de-nitrification resulting in modest nitrous oxide emissions. Under drier conditions such as intermittent flooding, methane emissions fall and nitrous oxide emissions increase. Increased nitrogen fertilizer use increases nitrous oxide emissions and is usually accompanied by reduced organic matter applications which decreases methane emissions. These mechanisms cause a generally inverse relationship between methane and nitrous oxide emissions. Reduction of methane from rice agriculture to control global warming comes with tradeoffs with increased nitrous oxide emissions. 5). High Spatial Resolution Maps of Emissions Produced. Maps of methane and nitrous oxide emissions at a resolution of 5 min × 5 min have been produced based on the composite results of this research. These maps are necessary for both scientific and policy uses

Assessing nitrate contamination risks in groundwater : a machine learning approach

Groundwater is one of the primary sources for the daily water requirements of the masses, but it is subjected to contamination due to the pollutants, such as nitrate, percolating through the soil with water. Especially in built-up areas, groundwater vulnerability and contamination are of major concern, and require appropriate consideration. The present study develops a novel framework for assessing groundwater nitrate contamination risk for the area along the Karakoram Highway, which is a part of the China Pakistan Economic Corridor (CPEC) route in northern Pakistan. A groundwater vulnerability map was prepared using the DRASTIC model. The nitrate concentration data from a previous study were used to formulate the nitrate contamination map. Three machine learning (ML) models, i.e., Support Vector Machine (SVM), Multivariate Discriminant Analysis (MDA), and Boosted Regression Trees (BRT), were used to analyze the probability of groundwater contamination incidence. Furthermore, groundwater contamination probability maps were obtained utilizing the ensemble modeling approach. The models were calibrated and validated through calibration trials, using the area under the receiver operating characteristic curve method (AUC), where a minimum AUC threshold value of 80% was achieved. Results indicated the accuracy of the models to be in the range of 0.82–0.87. The final groundwater contamination risk map highlights that 34% of the area is moderately vulnerable to groundwater contamination, and 13% of the area is exposed to high groundwater contamination risk. The findings of this study can facilitate decision-making regarding the location of future built-up areas properly in order to mitigate the nitrate contamination that can further reduce the associated health risks. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Muhammad Imran” is provided in this record*

Ataxic Variant Of Guillain Barre Syndrome: A Case Report

A 17-year-old girl was admitted after acute onset of unsteady gait succeeding acute gastroenteritis. Neurological examination reported normal power in all four limbs, impaired finger-nose, heel-shin tests, areflexia and ataxic gait. We eliminated other diseases with cerebellar symptoms; for example, Wernicke encephalopathy, multiple sclerosis, cerebellar vascular disease , encephalitis in the brain stem and cerebellum. Blood serum collected from the patient during the acute phase showed no anti-ganglioside antibodies. As the patient presented with evident cerebellar ataxia without muscle weakness, ophthalmoplegia or proprioceptive sensory disruption a diagnosis of ataxic form of Guillain-Barré syndrome (GBS) after nerve conduction studies. Though ataxic GBS is not a settled impression, we should have to give heed to the potential existence of such a scarce GBS variant

Predictors of Early Seizures After First Acute Stroke

ABSTRACT Background and objective: There is a lack of local data regarding the frequency and predictors of early seizures after stroke. The objective of this study was to determine the frequency of early seizures after stroke and identify the predictors which lead to them after first acute stroke. Methods: This cross-sectional observational study was conducted in the Department of Neurology, Pakistan Institute of Medical Sciences, Islamabad from October 2021 to June 2022. A total of 310 consecutive eligible patients of acute stroke were recruited. Key inclusion criteria included any patient of \u3e20 years of age with confirmed diagnosis of stroke on imaging, non-traumatic, with no history of seizures in past. Data was analyzed by SPSS version 23.0. Results: The mean age of patients in the seizures group was 48.40 ± 20.9 years. Hypertension was the most common co-morbid present in 225 (76.5%) patients. Early seizures were found in 52 (16.8%) patients with 42 (80.76%) having seizures in first 24 hours of stroke (p value 0.001). On National Institute of Health Sciences Scale (NIHSS) score most patients 125 (40.3%) had moderate severity score i.e. score in between 7 to 25 (p value 0.05). Ischemic stroke was identified as the stroke variety with most of the early seizures i.e. 16 (30.76%) (p value 0.003). Conclusion: Early seizures were not infrequent after acute stroke (16.77%) in our study. Early seizures were associated with younger age, cortical region lesion, ischemic stroke, followed by cerebral venous thrombosis. Higher NIHSS score and greater disability was associated with increased incidence of early seizures

Dysphagia among Middle-Aged Females

Objective: To assess the association of dysphagia with iron deficiency anemia in female patients. Study Design: Descriptive Study Setting & Duration: Department of ENT at Fauji Foundation Hospital Rawalpindi from April 2019 to April 2021. Material and Methods: Approval of the study was obtained from the Hospital Ethical Committee and then Informed Consent was obtained from all the patients. A total of 42 female patients with dysphagia were selected by Consecutive convenient sampling. After detailed history and physical examination, Complete Blood Count and X-ray Barium Swallow were done in all these patients, followed by Rigid Endoscopy under GA. Tissue biopsy was done in all the patients from suspicious areas. The data was analyzed for frequencies by SPSS 24. Results: 42 female patients were included in this study. The mean age of these patients was 46.30 years, ranging from 32 to 65 years. 40 (95%) of these patients showed Esophageal webs in the cricopharyngeal region, while 2 (5%) of them had irregular strictures in the post cricoid region of Hypopharynx. Iron deficiency anaemia was found in 32 (76.19%) patients. Histopathology report showed Squamous Cell Carcinoma in 2 patients with post cricoid strictures, while the rest 40 with webs showed chronic inflammation with fibrosis. Rigid esophagoscopy with web dilatation was highly effective procedure for treatment in 40 (95%) patients. Repeated dilatations were needed in 14 (33%) of the patients. The 2 patients with malignancy underwent Chemo-radiotherapy. Conclusion:  Iron deficiency anemia has a strong association with dysphagia in middle age female patients and is a potential risk factor for malignant transformation. Timely diagnosis and prevention of anaemia may result not only in decrease in PVS but also a decreased incidence of hypopharyngeal carcinoma in the vulnerable population. Key words: Dysphagia, Iron deficiency anemia, Post cricoid Carcinoma

Comparison of Peritonsillar Bupivacaine versus Peritonsillar Dexamethasone in Post-Tonsillectomy Pain Management

Objective: To compare efficacy of Peritonsillar Dexamethasone with Peritonsillar Bupivacaine in managing post-tonsillectomy pain in children. Study design: Randomized Controlled Trial Setting & Period: ENT Department Fauji Foundation Hospital (FFH) Rawalpindi from 01-06-2019 to 31-11-2020. Material &Methods: A total of sixty patients of both genders between ages of 5-15 years fulfilling the recognized criteria for tonsillectomy were selected. They were equally divided into two groups; Group A received peritonsillar Bupivacaine while Group B received peritonsillar Dexamethasone. Mean post-tonsillectomy Visual Analogue Score (VAS) at 1st, 2nd and 7th day were recorded in both groups and compared using independent sample ‘t’ test. Results: In group A Mean post-tonsillectomy VAS at 24 hours was 6.73±1.44 SD while in group B it was 5.93±1.26 SD (p-value 0.025). Mean post-tonsillectomy VAS at 48 hours was 5.60±1.25 SD and 4.37±1.03 SD (p-value 0.000) respectively in groups A and B. At 7th post operative day, Mean VAS was noted as 3.27±0.74 SD and 2.30±0.79 SD (p-value 0.000) respectively in group A and B.  Conclusion: Peritonsillar Dexamethasone is more effective than peritonsillar Bupivacaine in controlling post-tonsillectomy pain in children. Statistically significant difference was noted for mean post-tonsillectomy VAS at 1st, 2nd and 7th day. Key Words: Tonsillectomy, visual analogue score, postoperative pain, dexamethasone, bupivacaine

Dysphagia among Middle-Aged Females

Objective: To assess the association of dysphagia with iron deficiency anemia in female patients. Study Design: Descriptive Study Setting & Duration: Department of ENT at Fauji Foundation Hospital Rawalpindi from April 2019 to April 2021. Material and Methods: Approval of the study was obtained from the Hospital Ethical Committee and then Informed Consent was obtained from all the patients. A total of 42 female patients with dysphagia were selected by Consecutive convenient sampling. After detailed history and physical examination, Complete Blood Count and X-ray Barium Swallow were done in all these patients, followed by Rigid Endoscopy under GA. Tissue biopsy was done in all the patients from suspicious areas. The data was analyzed for frequencies by SPSS 24. Results: 42 female patients were included in this study. The mean age of these patients was 46.30 years, ranging from 32 to 65 years. 40 (95%) of these patients showed Esophageal webs in the cricopharyngeal region, while 2 (5%) of them had irregular strictures in the post cricoid region of Hypopharynx. Iron deficiency anaemia was found in 32 (76.19%) patients. Histopathology report showed Squamous Cell Carcinoma in 2 patients with post cricoid strictures, while the rest 40 with webs showed chronic inflammation with fibrosis. Rigid esophagoscopy with web dilatation was highly effective procedure for treatment in 40 (95%) patients. Repeated dilatations were needed in 14 (33%) of the patients. The 2 patients with malignancy underwent Chemo-radiotherapy. Conclusion:  Iron deficiency anemia has a strong association with dysphagia in middle age female patients and is a potential risk factor for malignant transformation. Timely diagnosis and prevention of anaemia may result not only in decrease in PVS but also a decreased incidence of hypopharyngeal carcinoma in the vulnerable population. Key words: Dysphagia, Iron deficiency anemia, Post cricoid Carcinoma