Some studies of the reactions of aromatic nitro compounds with nitrogen and carbon nucleophiles

Kinetic and equilibrium studies have been made of the reactions of a series of ring-substituted anilines with l,3,5-trinitrobenzene (TNB) and with 4- nitrobenzofuroxan (4-NBF) in dimethyl sulfoxide (DMSO). There is evidence from (^1)H NMR spectroscopy that in the presence of Dabco these reactions yield anionic σ-adducts. Kinetic studies are compatible with a two-step process involving initial nucleophilic attack by amine to give a zwitterionic intermediate which can transfer an acidic proton to Dabco. In the case of TNB the proton transfer step is rate-limiting due to the high rate of reversion of the zwitterion to reactants. Measurement of substituent effects shows that values of the equilibrium constant K(_1) for the initial zwitterions formation decrease by a factor of ca 1000 as R, the ring substituent in the anilines, is changed from 4-OMe to 3-CN (p=-3.82), while values of K(_Dabco) for the proton transfer equilibrium increase by a similar factor (p=+3.62). Hence overall values of K(_1)Doabco show only a small variation with the nature of R. Related studies with 4-NBF indicate that there is a balance between nucleophilic attack and proton transfer as the rate limiting step. This is due to the lower value for the rate of reversion of the zwitterion to reactants in the case of 4- NBF, relative to TNB. Values of K(_Doabco) are found to be larger for the 4-NBF reaction than for the TNB reaction, indicating greater electron withdrawing ability for the 4- NBF system than for TNB .(_pKa) values in DMSO for the nine aniline derivatives used were measured using the proton transfer equilibrium with 2,4-dimtrophenol. (^1)H NMR studies in d(_6)-DMSO show that the carbanions of nitromethane, nitroethane and 2-nitropropane add to 4-nitrobenzofiirazan derivatives to give carbon- bonded σ-adducts. With time there is evidence for the base-catalysed elimination of nitrous acid from the adducts to yield anionic alkene derivatives. Kinetic and equilibrium results for the corresponding reactions in methanol have been measured. Three ring-substituted benzyl triflones were prepared and reactions of the carbanions formed from them with 4,6-dinitrobenzofuroxan, 1,3,5-trinitrobenzene and benzofurazan derivatives were examined. There is evidence for the initial formation of σ-adducts followed by rapid elimination of HSO2CF3. Rate constants for these reactions in methanol are reported

EVALUATING THE EFFECT OF INDUSTRIAL EFFLUENTS ON CHEMICAL COMPOSITION OF SOIL IN VILLAGE DINGI, DISTRICT HARIPUR

The present report is an outcome of research work conducted in Dingi village, District Haripur in 2012. The research aimed to assess and analyze the effects of industrial effluents on the soil fertility of the village, investigate contributing factors responsible for soil pollution and underlying causes creating the problems. Data analysis revealed that area had problems pertaining to water and soil quality. The key factors affecting soil fertility were the careless discharge of the untreated industrial effluents from Hattar Industrial Estate (HIE) into the natural stream passing through village. The results were compared with the soil standards set by the World Wide Fund for Nature (WWF) and European Committee Commission (ECC) and all of these were exceeding the permissible limits and affecting the soil fertility. The soils were found not fit for agriculture. The investigation highlighted the need to take some effective steps to manage the monitoring program set for checking of industries by the government according to set rules and regulation

Are disaggregate industrial returns sensitive to economic policy uncertainty

© 2019 Elsevier B.V. This study investigates the impact of economic policy uncertainty on disaggregate US sector based returns. Our work is motivated by the presence of non-linear relationship between US economic policy uncertainty and equity returns of sampled US sectors. The paper uses weekly data from January 1995 to December 2015 for all the return indices and economic policy uncertainty data mainly based on policy issues, provision set for the US federal tax code and disagreement among economic forecasters. Our results indicate that information technology, utilities, industrial and telecommunication sectors remain insensitive to changes in the US economic policy uncertainty. However, financial and the consumer discretionary sectors show significant long run asymmetric relationship with the EPU.Accepted versio

Optic nerve sheath diameter evaluated by transorbital sonography in healthy volunteers from Pakistan

Objective: Raised intracranial pressure (ICP) is a common manifestation of severe brain injury. Rapid diagnosis and timely intervention is required to prevent secondary brain damage and death. Measurement of optic nerve sheath diameter (ONSD) by ultrasound is increasingly used as a marker to detect raised ICP. Knowledge of normal ONSD in a healthy population is essential to interpret this measurement. We aimed to evaluate normal optic nerve sheath diameter in healthy volunteers in Pakistan. Methodology: It was a prospective, observational study in which one hundred healthy volunteers of Pakistani origin, aged more than 18 years were recruited in the study. The ultrasound probe was placed on the superior and lateral aspect of the orbit against the upper eyelid with the eye closed. For each subject, the primary investigator performed three measurements on each eye. The measurements of each eye were then averaged to yield a mean ONSD. Results: The median ONSD of right eye was 4.84 mm and 95% of individuals had mean ONSD in the range 4.84–4.97 mm while the median ONSD of left eye was 4.86 mm and 95% of individuals had mean ONSD in the range 4.85–4.96 mm. There was no difference among the 3 repeated measures of ONSD in each eye. There was no relationship between ONSD with age, gender and measurement taken between left and right eyes. Conclusion: 95% of study sample have an ONSD less than 4.82 mm. ONSD more than 4.82 mm in this population should be considered abnormal and may reflect raised intracranial pressure

Drop size in a liquid pulsed sieve-plate extraction column

Peer reviewedPublisher PD

City tumour board Karachi: an innovative step in multidisciplinary consensus meeting and its two years audit.

Management of cancer patients is a team work which usually comprises of surgeons, oncologists, radiologists, pathologists, psychiatrist, nutritionist and a nurse. Any patient who is suffering from any tumour needs a multimodality meeting as cancer treatment is not a single persons job. Most of the time, it is difficult to get the whole team together for a plan discussion due to their busy schedule. This problem was overcome by starting a tumour board meeting early morning of Sunday in Karachi which was named City Tumour Board (CTB) Karachi . Its first meeting was held on Sunday March 28, 2010 and since then it takes place regularly fortnightly. Till March 2012, 44 sessions were conducted and total 264 cases were discussed. Here we present an audit of these two years. On average, in 60% of cases, tumour was up (36%) or down staged (12%) while in 52% of cases the stage remained unchanged. In 70% of cases (inclusive of above 60%), initial treatment plan was changed after discussion in the tumour board. This data signifies the importance of tumour board especially in a Pakistani setup where patient and even referring persons are not well aware of this disease and its outcome. It is advisable that every case should be discussed in tumour board before embarking on any treatment so that the best treatment plan can be given. It is also important that all relevant specialists should be present in the tumour board when planning for any treatment

Working in a Physically Dangerous Work Environment: Employee Vitality and Sustainable Behavior

There is a limited understanding of the antecedents and consequences of employee vitality during war zone exposure. The current study is one of the first ones to investigate the direct effects of perceived danger on employee vitality by collecting data from Afghanistan, one of the most dangerous countries in the world. Furthermore, it was investigated how employee vitality affects sustainable behavior at the workplace. The hypotheses of the study have been tested by using data from two surveys collected from 192 employees working in small-sized private businesses in Afghanistan. The results indicate that high levels of perceived danger negatively impact employee vitality at work. In addition, we found that employees with vitality engage in more pro-environmental behavior in the workplace. The engagement of vital employees in pro-environmental behavior is higher among those employees who have a high level of environmental awareness. This paper concludes by presenting the limitations and implications of this study, as well as highlighting potential avenues for future research

Activity of Indoleamine 2, 3 Dioxygenase (IDO) in Type 2 Diabetes Mellitus Patients in Pakistan

To assess the activity of Indoleamine 2, 3 Dioxygenase (IDO) in Type 2 Diabetes Mellitus Patients in PakistanMethods: In this prospective study, activity and expression of IDO , was assessed in sera of diabetics and healthy controls (n=28). Colorimetric Assay was performed to analyze IDO activity in samples.Results: A significant difference was observed between the means of control and diabetic patients with a p-value of 0.0001.Conclusion: IDO concentrations were significantly higher in the serum of samples of diabetes mellitus patients as compared to contro