A novel multi-model estimation of phosphorus in coal and its ash using FTIR spectroscopy.

The level of phosphorus must be carefully monitored for proper and effective utilization of coal and coal ash. The phosphorus content needs to be assessed to optimize combustion efficiency and maintenance costs of power plants, ensure quality, and minimize the environmental impact of coal and coal ash. The detection of low levels of phosphorus in coal and coal ash is a significant challenge due to its complex chemical composition and low concentration levels. Effective monitoring requires accurate and sensitive equipment for the detection of phosphorus in coal and coal ash. X-ray fluorescence (XRF) is a commonly used analytical technique for the determination of phosphorus content in coal and coal ash samples but proves challenging due to their comparatively weak fluorescence intensity. Fourier Transform Infrared spectroscopy (FTIR) emerges as a promising alternative that is simple, rapid, and cost-effective. However, research in this area has been limited. Until now, only a limited number of research studies have outlined the estimation of major elements in coal, predominantly relying on FTIR spectroscopy. In this article, we explore the potential of FTIR spectroscopy combined with machine learning models (piecewise linear regression-PLR, partial least square regression-PLSR, random forest-RF, and support vector regression-SVR) for quantifying the phosphorus content in coal and coal ash. For model development, the methodology employs the mid-infrared absorption peak intensity levels of phosphorus-specific functional groups and anionic groups of phosphate minerals at various working concentration ranges of coal and coal ash. This paper proposes a multi-model estimation (using PLR, PLSR, and RF) approach based on FTIR spectral data to detect and rapidly estimate low levels of phosphorus in coal and its ash (R 2 of 0.836, RMSE of 0.735 ppm, RMSE (%) of 34.801, MBE of - 0.077 ppm, MBE (%) of 5.499, and MAE of 0.528 ppm in coal samples and R 2 of 0.803, RMSE of 0.676 ppm, RMSE (%) of 38.050, MBE of - 0.118 ppm, MBE (%) of 4.501, and MAE of 0.474 ppm in coal ash samples). Our findings suggest that FTIR combined with the multi-model approach combining PLR, PLSR, and RF regression models is a reliable tool for rapid and near-real-time measurement of phosphorus in coal and coal ash and can be suitably modified to model phosphorus content in other natural samples such as soil, shale, etc.

Petrographic and Geochemical Controls on Methane Genesis, Pore Fractal Attributes, and Sorption of Lower Gondwana Coal of Jharia Basin, India.

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.

Variation in Pore Structure and Associated Fractal Dimensions of Barakar and Barren Measures Carbon-Rich Gas Shales of Jharia Basin, India.

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.

Organo-Lithotype Controls on Cleat/Fractures, Matrix-Associated Pores, and Physicomechanical Properties of Coal Seams of Raniganj Coalfield, India.

The organo-lithotype properties of Barakar and Raniganj Formation coal seams have been investigated to assess the process of cleat origin, occurrence, and their influence on strength properties. Coal cleats have wide applications in coalbed methane gas recovery, underground mine strata mechanics, beneficiation, and pulverization. However, there is very limited information available on the cleat occurrence and controlling parameters of Indian coals. In this view, a total of 31 coal samples were retrieved from eight exploratory boreholes intersecting coal-bearing formations like Barakar and Raniganj in the Raniganj Coalfield. We identified four distinct lithotypes in coal seams: (i) B, bright coal; (ii) Db, dull banded coal; (iii) Bb, bright banded coal; and (iv) Bd, banded coal. The abundance of bright-band-associated lithotype indicates organic matter that attained the early anoxic conditions after deposition. The cleat system in Barakar coal is comparatively better than in Raniganj coal controlled by the lithotype, type of organic matter, thermal maturity, and gelification extent. The carbon enrichment process in coal mainly controls the megascopic cleat genesis pattern. The positive trend of cleat intensities with the depth of coal seams as determined by megascopic, microscopic, and scanning electron microscope (SEM) studies postulates that the macro- to nanocleats are interdependent and developed during devolatilization due to loss of plasticity. The field emission scanning electron microscopy (FE-SEM) photographs have shown intricate microfractures and pore structures owing to the epigenetic characteristics. Vitrinite bands indicate that it comprises the partially deformed planer cleat system. The resistance to quartz weathering nature attributed to coal brittleness properties also contributed to cleat genesis. The total clay content exhibits an inverse relationship with different cleat intensities, suggesting that hydrous clay swells due to its inherent ultrafine characteristics, thus not supporting the cleat construction. However, it ropes the development of the irregular crack when organo-inorganic matter achieves the dry thermal conditions. The microfractures linked with different pore structures in studied coals can be classified into seven types: (i) vitrite-associated regular open-slit pores, (ii) vitriinertite-char allied irregular pores, (iii) irregular fracture-pore partially filled with clay, (iv) fissile pores along bedding planes of clay, (v) organic pores evolved due to external heat received from intrusives, (vi) deep organic pores evolved during compaction and thermal transformation, and (vii) pore fractures blocked by boghead algae. The clay content showed a positive relationship with physicomechanical properties, signifying the cementing characteristics of clay holding fractures and pores. There is significant variation in the strength properties of Barakar and Marren measures coal influenced by thermal maturity, lithotype characteristics, and organo-inorganic content.

The United Kingdom Diabetic Retinopathy Electronic Medical Record Users Group: Report 3: Baseline Retinopathy and Clinical Features Predict Progression of Diabetic Retinopathy.

PURPOSE: To determine the time and risk factors for developing proliferative diabetic retinopathy (PDR) and vitreous hemorrhage (VH). DESIGN: Multicenter, national cohort study. METHODS: Anonymized data of 50 254 patient eyes with diabetes mellitus at 19 UK hospital eye services were extracted at the initial and follow-up visits between 2007 and 2014. Time to progression of PDR and VH were calculated with Cox regression after stratifying by baseline diabetic retinopathy (DR) severity and adjusting for age, sex, race, and starting visual acuity. RESULTS: Progression to PDR in 5 years differed by baseline DR: no DR (2.2%), mild (13.0%), moderate (27.2%), severe nonproliferative diabetic retinopathy (NPDR) (45.5%). Similarly, 5-year progression to VH varied by baseline DR: no DR (1.1%), mild (2.9%), moderate (7.3%), severe NPDR (9.8%). Compared with no DR, the patient eyes that presented with mild, moderate, and severe NPDR were 6.71, 14.80, and 28.19 times more likely to develop PDR, respectively. In comparison to no DR, the eyes with mild, moderate, and severe NPDR were 2.56, 5.60, and 7.29 times more likely to develop VH, respectively. In severe NPDR, the eyes with intraretinal microvascular abnormalities (IRMA) had a significantly increased hazard ratio (HR) of developing PDR (HR 1.77, 95% confidence interval [CI] 1.25-2.49, P = .0013) compared with those with venous beading, whereas those with 4-quadrant dot-blot hemorrhages (4Q DBH) had 3.84 higher HR of developing VH (95% CI 1.39-10.62, P = .0095). CONCLUSIONS: Baseline severities and features of initial DR are prognostic for PDR development. IRMA increases risk of PDR whereas 4Q DBH increases risk of VH.

The UK Diabetic Retinopathy Electronic Medical Record (UK DR EMR) Users Group, Report 2: real-world data for the impact of cataract surgery on diabetic macular oedema.

AIM: To assess the rate of 'treatment-requiring diabetic macular oedema (DMO)' in eyes for the two years before and after cataract surgery. METHODS: Multicentre national diabetic retinopathy (DR) database study with anonymised data extraction across 19 centres from an electronic medical record system. INCLUSION CRITERIA: eyes undergoing cataract surgery in patients with diabetes with no history of DMO prior to study start. The minimum dataset included: age, visual acuity (all time-points), injection episodes, timing of cataract surgery and ETDRS grading of retinopathy and maculopathy. MAIN OUTCOME MEASURE: rate of developing first episode of treatment-requiring DMO in relation to timing of cataract surgery in the same eye. RESULTS: 4850 eyes met the inclusion criteria. The rate of developing treatment-requiring DMO in this cohort was 2.9% in the year prior to surgery versus 5.3% in the year after surgery (p<0.01). The risk of 'treatment-requiring DMO' increased sharply after surgery, peaking in the 3-6 months' period (annualised rates of 5.2%, 6.8%, 5.6% and 4.0% for the 0-3, 3-6, 6-9 and 9-12 months' post-operative time periods respectively). Risk was associated with pre-operative grade of retinopathy: risk of DMO in the first year post-operatively being 1.0% (no DR pre-operatively), 5.4% (mild non-proliferative diabetic retinopathy; NPDR), 10.0% (moderate NPDR), 13.1% (severe NPDR) and 4.9% (PDR) (p<0.01). CONCLUSIONS: This large real-world study demonstrates that the rate of developing treatment-requiring DMO increases sharply in the year after cataract surgery for all grades of retinopathy, peaking in the 3-6 months' postoperative period. Patients with moderate and severe NPDR are at particularly high risk.

The United Kingdom Diabetic Retinopathy Electronic Medical Record Users Group, Report 1: baseline characteristics and visual acuity outcomes in eyes treated with intravitreal injections of ranibizumab for diabetic macular oedema.

AIMS: To describe baseline characteristics and visual outcome for eyes treated with ranibizumab for diabetic macular oedema (DMO) from a multicentre database. METHODS: Structured clinical data were anonymised and extracted from an electronic medical record from 19 participating UK centres: age at first injection, ETDRS visual acuity (VA), number of injections, ETDRS diabetic retinopathy (DR) and maculopathy grade at baseline and visits. The main outcomes were change in mean VA from baseline, number of injections and clinic visits and characteristics affecting VA change and DR grade. RESULTS: Data from 12 989 clinic visits was collated from baseline and follow-up for 3103 eyes. Mean age at first treatment was 66 years. Mean VA (letters) for eyes followed at least 2 years was 51.1 (SD=19.3) at baseline, 54.2 (SD: 18.6) and 52.5 (SD: 19.4) at 1 and 2 years, respectively. Mean visual gain was five letters. The proportion of eyes with VA of 72 letters or better was 25% (baseline) and 33% (1 year) for treatment naïve eyes. Eyes followed for at least 6 months received a mean of 3.3 injections over a mean of 6.9 outpatient visits in 1 year. CONCLUSIONS: In a large cohort of eyes with DMO treated with ranibizumab injections in the UK, 33% of patients achieved better than or equal to 6/12 in the treated eye at 12 months compared with 25% at baseline. The mean visual gain was five letters. Eyes with excellent VA at baseline maintain good vision at 18 months.

UK AMD EMR USERS GROUP REPORT V: benefits of initiating ranibizumab therapy for neovascular AMD in eyes with vision better than 6/12.

BACKGROUND/AIMS: To study the effectiveness and clinical relevance of eyes treated with good (better than 6/12 or >70 Early Treatment Diabetic Retinopathy Study letters) visual acuity (VA) when initiating treatment with ranibizumab for neovascular age-related macular degeneration (nAMD) in the UK National Health Service. Currently eyes with VA better than (>) 6/12 are not routinely funded for therapy. METHODS: Multicentre national nAMD database study on patients treated 3-5 years prior to the analysis. Anonymised structured data were collected from 14 centres. The primary outcome was the mean VA at year 1, 2 and 3. Secondary measures included the number of clinic visits and injections. RESULTS: The study included 12 951 treatment-naive eyes of 11 135 patients receiving 92 976 ranibizumab treatment episodes. A total of 754 patients had baseline VA better than 6/12 and at least 1-year of follow up. Mean VA of first treated eyes with baseline VA>6/12 at year 1, 2, 3 were 6/10, 6/12, 6/15, respectively and those with baseline VA 6/12 to >6/24 were 6/15, 6/17, 6/20, respectively (p values <0.001 for comparing differences between 6/12 and 6/12-6/24 groups). For the second eyes with baseline VA>6/12, mean VA at year 1, 2, 3 were 6/9, 6/9, 6/10 and those with baseline VA 6/12 to >6/24 were 6/15, 6/15, 6/27, respectively (p values <0.001-0.005). There was no significant difference in the average number of clinic visits or injections between those with VA better and worse than 6/12. CONCLUSIONS: All eyes with baseline VA>6/12 maintained better mean VA than the eyes with baseline VA 6/12 to >6/24 at all time points for at least 2 years. The significantly better visual outcome in patients who were treated with good baseline VA has implications on future policy regarding the treatment criteria for nAMD patients' funding.

The neovascular age-related macular degeneration database: report 2: incidence, management, and visual outcomes of second treated eyes.

PURPOSE: To study the characteristics of second treated eyes in patients with neovascular age-related macular degeneration (nAMD) treated with ranibizumab in the United Kingdom National Health Service. DESIGN: Multicenter national nAMD database study. PARTICIPANTS: Twelve thousand nine hundred fifty-one treatment-naïve eyes of 11,135 patients receiving 92,976 ranibizumab injections. METHODS: Up to 5 years of routinely collected, anonymized data within electronic medical record systems were extracted remotely from 14 centers. Participating centers exclusively used ranibizumab to treat nAMD (loading phase of 3 monthly injections followed by monthly visits and pro re nata re-treatment). The minimum data set included: age, logarithm of the minimum angle of resolution (logMAR) visual acuity (VA) at baseline and at all subsequent visits, and injection episodes. MAIN OUTCOME MEASURES: Baseline, change and actual VA over 3 years, and number of treatments and clinic visits. RESULTS: During the study, 1816 (16.3%) of the 11 135 patients received treatment to the fellow eye. Mean baseline and final VA were 0.66 (standard deviation, 0.32) and 0.65 (0.40) for first treated eyes and 0.41 (0.34) and 0.56 (0.40) for second treated eyes. The rate of VA loss after the loading phase was similar in first and second treated eyes (0.03 and 0.05 logMAR units/year). When fellow eyes with baseline VA worse than 20/200 were excluded to restrict analyses to eyes at risk of nAMD, the rate of second-eye involvement was 14.0% per year (42%/3 years). Mean number of injections/visits in years 1, 2, and 3 were similar for first and second treated eyes (5.6/8.2, 3.9/8.0, 3.8/8.2 and 5.5/8.7, 3.6/9.4, and 3.8/9.1, respectively). CONCLUSIONS: Second treated eyes with nAMD commence treatment with better baseline VA, do not show significant vision gain but maintain better VA than first treated eyes at all time points for at least 3 years, making them the more important eye functionally. These data highlight the high burden of second eye involvement, with almost half of all eyes at risk requiring bilateral treatment by 3 years, and the need for regular monitoring of fellow eyes for best visual outcomes which theoretically may reduce the benefits of extended monitoring regimens.

Irreversible blindness due to multiple tuberculomas in the suprasellar cistern.

A 14-year-old girl developed fever, severe headache, vomiting, and no light perception in both eyes over a 3-day period without a previous complaint of visual or other neurologic difficulties. Neuro-ophthalmologic examination was normal apart from meningismus and blindness. Brain imaging showed ventriculomegaly and multiple enhancing nodules around the optic chiasm. Lumbar puncture showed an elevated opening pressure with lymphocytic pleocytosis. Polymerase chain reaction and enzyme-linked immunoabsorbent antibody tests on the cerebrospinal fluid were positive for Mycobacterium tuberculosis. There was no evidence of tuberculosis elsewhere in the body. Standard antituberculous treatment, including corticosteroids, did not reverse the blindness.

Isolated abscess of extraocular muscle in two young boys: clinical and imaging features.

PURPOSE: To report two cases of a cystic isolated extraocular muscle abscess in a young boy. METHOD: Case report. RESULTS: Two cases of young boys with a cystic isolated extraocular muscle abscess are described. Each presented as an inflammatory lesion in the orbit that had been stable for approximately three weeks. Neurodiagnostic imaging of the two cases revealed a cystic lesion in close proximity to an extraocular muscle. An ultrasound-guided aspiration of each lesion revealed material that, when cultured, grew Staphylococcus aureus. Both patients recovered with appropriate antibiotic therapy. No other systemic illness could be identified in either case. CONCLUSION: These cases illustrate that an isolated abscess involving an extraocular muscle may present like an inflammatory cyst even without any evidence of systemic illness. When evaluating and managing such lesions, the authors recommend the use of ultrasound-guided aspiration to avoid complications arising from delay in diagnosis and inappropriate treatment.

Use of the direct puncture technique in management of capillaro-venous malformations: case report.

BACKGROUND: Preoperative devascularization of the capillaro-venous malformations located in the aero-digestive tract is important for surgeons, to minimize blood loss during surgical excision of malformations. CASE PRESENTATION: Here we present two cases of capillaro-venous malformation in which we could successfully achieve preoperative devascularization, by directly injecting n-butyl cyano acrylate into the capillaro-venous bed. This technique is relatively easy, safe and cheap, and can be carried out immediately before surgery.