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1.
ACS Omega ; 7(1): 299-324, 2022 Jan 11.
Article in English | MEDLINE | ID: mdl-35036701

ABSTRACT

The Barakar coal seams of Jharia Basin have been evaluated for the geochemical and petrographic control of coalbed methane (CBM) reservoir characteristics. The coal core samples are analyzed for the total gas content, gas chromatography, stable isotopes (δ13C1), and geochemical, petrographic and vitrinite reflectance. The significant face (1.6-7.6%) and butt (0.9-5.3%) cleat intensities specify the brittle characteristics of coal seams and also favor the gas flow mechanism. The thermal cracking position of hydrocarbon compounds was evaluated, which signifies the excellent source rock potential of coal for gas genesis. The inputs of type III and IV organic matter illustrated by the van Krevelan diagram signify thermally matured coal seams. The low values of sorption time (τ) between 2.1 and 5.6 days designate excellent diffusion characteristics that is favored by the cleat intensities. The values of total gas content and sorption capacity (V L) reveal that moderate saturation indicates a higher gas content, attributed to the seam thickness and thermal maturity. Similarly, the CH4 concentrations (89.4-96.6 vol %) display that the genesis pattern is a function of thermal maturity; however, some samples fall under the mixed type substantiated by the stable isotope (δ13C1) (-25.40 to -64.90‰), emphasizing bacterial hold by seasonal influx of freshwater. The ternary facies diagram (Vmmf, Immf, Lmmf) also supports notable generation of methane gas and storage in the coal seams of the Jharia Basin. The volume percentage of each maceral determined from petrographic study was used to estimate the fraction of conversion (f) of the organic content (0.19-0.97). The values of "f" indicate that the Barakar coal has undergone maximum conversion, which may be attributed to the older early Permian coal and placed at a greater depth after deposition due to the basin sink. The high fraction of conversion and thermal maturity may also be explained due to the existence of volcanic intrusion (sills and dykes). The uniformity in the distribution of functional groups is shown by Fourier transform infrared spectra representing moderate to stronger peaks of aromatic carbon (CO and C=C) between 1750 and 1450 cm-1, which indicates that the presence of a larger total organic carbon content likely validates the removal of aliphatic compounds during gas genesis. The variations in the BET curve have been categorized as H1 hysteresis following the type II adsorption pattern, suggesting that cylindrical pores and some of the coal samples have a type IV H4 hysteresis pattern, characterized as the slit type of pores. The average values of the pore diameter indicate the dominance of mesopores suitable for gas storage and release and hence a major part of the pore volume is contributed by the mesopores having a width mainly between 2.98 and 4.48 nm. The significant role of the meso-macropore network (D 1 fractals) in methane storage of the coal matrix is represented by a moderate positive relationship of V L with D 1, which accentuated that meso-macropores developed due to devolatilization and dehydration of organic matter and also by geochemical alteration of macerals and minerals formed heterogenetic inner surfaces suitable for gas adsorption. The estimated recoverable resource applying Mavor Pratt methods is 8.78 BCM, which is found to be a more realistic resource value for the studied CBM block.

2.
ACS Omega ; 6(43): 28678-28698, 2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34746563

ABSTRACT

The carbon-rich Barakar and Barren Measures shale beds of the Jharia basin were evaluated for variation in pore size, pore structure, and fractal dimensions. The shale core samples were obtained from exploratory boreholes drilled at the Jharia basin. The shale samples were analyzed for organo-inorganic composition by FTIR, pore size, and pore structure using BET low-pressure N2 adsorption and pore geometry through FE-SEM photographs. The shale samples have significant carbon-rich content and are intercalated-banded in nature. The pore structures were evaluated through N2 isotherms and validated by SEM images, revealing the mixed contribution of organo-inorganic matter in pore formations controlled by geochemical alteration, diagenesis, and mineral interaction. The rough internal surfaces of the pore were evaluated by categorizing them into fractals D 1, D 2, and D 3. It is observed that the D 2 type of fractals is in abundance associated with mesopores. The positive trend of fractals with pore size, pore structure, depth, fixed carbon, and TOC suggests the influence of different parameters on the formation of pore internal rugged surfaces in shale beds. The FE-SEM images indicate shallow to deep pores with different pore structures with fair to good pore connectivity. In summary, the shale beds of Jharia have heterogeneous complex pore structures, a rough surface, and sorption mechanisms controlled by weathering/alteration, depositional conditions, and organo-inorganic content. In shale beds, gas storage and transport phenomena are directly related to pore size distribution, pore structure, and associated fractal dimensions. The calculated values using the proposed empirical models for porosity (EPOf) and permeability (EPEf) showed excellent linear correlation with the measured porosity (MPOc, R 2 = 0.8577) and permeability (MPEc, R 2 = 0.8577), which are close to measured values. The curve matching of EPOf with MPOc and EPEf with MPEc follows a similar path, validating the results and suitability of the models. Hence, the proposed models may be considered to estimate the porosity and permeability of shale and coal beds.

3.
Gen Hosp Psychiatry ; 65: 74-81, 2020.
Article in English | MEDLINE | ID: mdl-32535329

ABSTRACT

BACKGROUND: Sleep walking (SW) is a parasomnia behavior characterized by repetitious occurrence of ambulation during a partial arousal from non-rapid eye movement (NREM) sleep. Sleep-related eating (SRE) is one of the complex sleep behaviors that may accompany SW. Emerging evidence suggests that NREM parasomnias can be associated with atypical antipsychotic medication use. METHODS: We present a case series (n = 5) and a systematic review of the literature of cases of SW, with or without SRE (n = 23), associated with atypical antipsychotic use. RESULTS: Twenty-eight cases of SW, with and without SRE, with a mean age of 44.8 years (S.D. = 15.04) and a male predominance (75%; n = 21) were identified. Quetiapine was the most commonly implicated medication with SW and SRE (n = 14). Remission from SW/SRE was noted in all cases with measures including antipsychotic dosage reduction, discontinuation of medication, switching to an alternate medication, and use of continuous positive airway pressure (CPAP) for comorbid obstructive sleep apnea (OSA) treatment. CONCLUSIONS: Sleep walking (SW), with or without sleep related eating (SRE), can be a rare but reversible side effect associated with use of atypical antipsychotics. More research is warranted to elucidate the mechanisms underlying SW and SRE associated with atypical antipsychotic use.


Subject(s)
Antipsychotic Agents/adverse effects , Feeding Behavior/drug effects , Parasomnias/chemically induced , Quetiapine Fumarate/adverse effects , Somnambulism/chemically induced , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult
4.
Children (Basel) ; 5(3)2018 Mar 02.
Article in English | MEDLINE | ID: mdl-29498675

ABSTRACT

Treatment options may be limited for infants with obstructive sleep apnea when there is no surgically correctable upper airway lesion. We therefore evaluated, retrospectively, the efficacy of low-flow oxygen as a therapeutic option for infant obstructive sleep apnea. We reviewed the medical charts of 23 infants who had undergone a therapeutic trial of low-flow oxygen during polysomnography. Split-night polysomnography was used in 21/23 subjects while 2/23 had undergone two separate, full-night polysomnography sleep architecture and respiratory findings on the baseline polysomnogram segment that was obtained in room air were compared with the segment on low-flow oxygen (0.25-1 L/min). Wilcoxon signed rank or McNemar's test were used as indicated for comparing apnea hypopnea index and measures of sleep architecture at baseline and with oxygen therapy. The mean (±SD) age of subjects was 4.8 (±2.7) months, with 52% being males. The median apnea hypopnea index fell from a baseline of 18 (range 7-43) to 3 (range 1-19; p = 0.001) on oxygen. The baseline median obstructive/mixed apnea index decreased from 2 (range 1-16) to 1 during oxygen therapy (range 0-1; p = 0.003). Additionally, a significant decrease in central apnea index (median interquartile range (IQR) 1 (0-2) vs. 0 (0-1), p = 0.002) was noted. Sleep efficiency remained unaffected, while O2 saturation (SaO2) average and SaO2 nadir improved on oxygen. We were able to confirm the utility of low-flow oxygen in reducing central, obstructive, and mixed apneas and improving average oxygen saturation in infants with obstructive sleep apnea (OSA).

7.
Bipolar Disord ; 17(6): 677-82, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26257194

ABSTRACT

OBJECTIVE: The aim of the present case report was to describe the late onset of recurrent mania in a patient after ischemic injury to the cerebellum and dorsolateral medulla. METHODS: We studied an 86-year-old male with no prior psychiatric history who developed recurrent episodes of mania following a brain stroke. Additionally, he had neurological symptom constellation typical of Wallenberg syndrome. RESULTS: Magnetic resonance imaging of the brain revealed infarction in the inferomedial right cerebellar hemisphere and the right dorsolateral medulla in the right posterior inferior cerebellar artery (PICA) distribution. He was successfully managed with a combination of antipsychotic and mood-stabilizer medications. CONCLUSIONS: Post-stroke mania may be one of the rare manifestations of Wallenberg syndrome. This case adds to the emerging literature on cerebellar involvement in mood regulation and pathology of mania.


Subject(s)
Antipsychotic Agents/therapeutic use , Bipolar Disorder , Brain Stem/pathology , Lateral Medullary Syndrome , Aged, 80 and over , Bipolar Disorder/diagnosis , Bipolar Disorder/etiology , Bipolar Disorder/physiopathology , Functional Neuroimaging/methods , Humans , Lateral Medullary Syndrome/complications , Lateral Medullary Syndrome/diagnosis , Lateral Medullary Syndrome/psychology , Magnetic Resonance Imaging/methods , Male , Recurrence , Treatment Outcome
8.
J Emerg Trauma Shock ; 7(4): 327-31, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25400398

ABSTRACT

Traumatic events after a road traffic accident (RTA) can be physical and/or psychological. Posttraumatic stress disorder (PTSD) is one of the major psychological conditions which affect accident victims. Psychological issues may not be addressed in the emergency department(ED) immediately. There have been reports about a mismatch between the timely referrals from ED to occupational or primary care services for these issues. If left untreated, there may be adverse effects on quality of life (QOL) and work productivity. Hospital expenses, loss of income, and loss of work could create a never ending cycle for financial difficulties and burden in trauma victims. The aim of our review is to address the magnitude of PTSD in post-RTA hospitalized patients in Indian subcontinent population. We also attempted to emphasis on few management guidelines. A comprehensive search was conducted on major databases with Medical Subject Headings (MeSH) term 'PTSD or post-traumatic stress' and Emergency department and vehicle or road or highway or automobile or car or truck or trauma and India. Out of 120 studies, a total of six studies met our inclusion criteria and were included in the review. Our interpretation of the problem is that; hospital expenditure due to trauma, time away from work during hospitalization, and reduction in work performance, are three major hits that can lead RTA victims to financial crisis. Proposed management guidelines are; establish a coordinated triage, implementing a screening tool in the ED, and provide psychological counseling.

9.
J Clin Sleep Med ; 10(5): 577-9, 2014 May 15.
Article in English | MEDLINE | ID: mdl-24812544

ABSTRACT

Complex sleep apnea syndrome (CompSAS) is characterized by predominant obstructive sleep disordered breathing with evolution of central disordered breathing following exposure to nasal continuous positive airway pressure (CPAP) therapy in obstructive sleep apnea (OSA) patients. We report a case of CompSAS associated with use of a nasal expiratory positive airway (nEPAP, Provent) device. We therefore recommend obtaining objective sleep data to confirm treatment effectiveness of the nEPAP device for OSA prior to long-term prescription. Further research is warranted to understand the underlying pathophysiological mechanisms and risk factors associated with CompSAS.


Subject(s)
Positive-Pressure Respiration/adverse effects , Sleep Apnea, Obstructive/etiology , Aged , Humans , Male , Nose , Polysomnography , Positive-Pressure Respiration/instrumentation , Sleep Apnea, Obstructive/physiopathology , Sleep Apnea, Obstructive/therapy
13.
Gen Hosp Psychiatry ; 34(2): 209.e9-11, 2012.
Article in English | MEDLINE | ID: mdl-21937118

ABSTRACT

Tacrolimus has been associated with severe neurotoxicity in organ transplant patients. Catatonia can be a rare manifestation of tacrolimus-induced neurotoxicity as we report two cases of catatonia in solid organ transplant patients on tacrolimus. Catatonic symptoms completely resolved in these patients after reducing the tacrolimus dosage or switching it to alternative immunosuppressants. Catatonia symptoms in organ transplant patients should alert clinicians to look for tacrolimus-induced neurotoxicity despite normal serum tacrolimus levels and neuroimaging findings.


Subject(s)
Catatonia/etiology , Immunosuppressive Agents/adverse effects , Neurotoxicity Syndromes/complications , Neurotoxicity Syndromes/etiology , Organ Transplantation , Tacrolimus/adverse effects , Female , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Tacrolimus/therapeutic use
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