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Background: The organic dyes with non-fullerene acceptors (NFAs) have aided in the creation of competitive organic solar cells (OSCs) with long-term sustainability. A series of NFA dyes (IDIC-R1-IDIC-R9) have been designed by varying the end-capped fluorinated moieties (PD1-PD6) at indaceno (IDIC) core., Methods: All the calculations were performed by density functional theory (DFT) and time-dependent DFT (TD-DFT)-based approaches. All the geometries were optimized at B3LYP/6-31G + (d,p) of DFT level at their ground state energies. Out of several density functionals, the CAM-B3LYP with 6-31G + (d,p) basis sets was selected after a benchmark study to carry out further calculations. All the dyes had their bandgaps in 0.11-3.12 eV while their starting reference dye had a bandgap value of 2.01 eV., Results: Their ionization potential (IP) implied that these dyes have strong tendency to lose electrons. The λ max of the dyes was slightly redshifted from the IDIC (476 nm) and IDIC-R (479 nm) when changing solvent polarity from methanol to DCM and then chloroforms. The natural bond orbital (NBO) analysis showed the (S63)LP → (C61-C62)π* with highest stabilization energy. Their electron injection analysis showed that these dyes can be a good anode material against the aluminum and gold electrodes. The intramolecular charge transfer (ICT) process and stability of the dyes were investigated using frontier molecular orbital (FMO) and natural bond orbital (NBO) analysis., Conclusion: Among all dyes, IDIC-R8 has the highest linear polarizability and second-order hyperpolarizability (β total ). All the dyes demonstrated promising non-linear optical (NLO) properties due to their low charge transfer barriers. Scientists would be able to exploit these properties to identify the best NLO materials for existing applications., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Autosomal recessive disorders are prevalent in Pakistan, a developing South Asian country where consanguineous marriages are common. This study seeks to determine the prevalence of monogenic causes in children presenting with nephrocalcinosis and nephrolithiasis at a dialysis and transplant center in Karachi, Pakistan. A retrospective analysis was conducted in children aged 1-18 years presenting with nephrocalcinosis, between 2010 and 2019. Demographic information, clinical profile, laboratory parameters and stone analysis were collected, on a pre-designed questionnaire. One hundred and twenty-six children were included, with 11 and 3 diagnosed with renal tubular acidosis and Bartter's syndrome respectively. Next-generation sequencing and Sanger sequencing was performed on 112 children. Eighty-seven patients were diagnosed with primary hyperoxaluria, with mutations in alanine-glyoxylate-aminotransferase gene found in 73, followed by glyoxylate reductase/hydroxy-pyruvate reductase in 13, and 4-hydroxy-2-oxaloglutarate aldolase in 1. Twenty-five patients reported negative for mutations. Sixty-four percent were males, with a statistically significant difference (p < 0.05). History of parental consanguineous marriage was found in 98% of the cohort. Fifty-four and 40 patients presented to the clinic with Chronic Kidney Disease Stage 1 and Stage 5, respectively, with a statistically significant difference p = 0.007. Mutations noted in our cohort are different and more severe than those reported in the developed world. The disease poses a major disease burden in developing world context with the only treatment option of combined liver-kidney transplantation not available in Pakistan., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Pediatric urolithiasis remains endemic in low-resource countries where infants constitute 17-40% of all children with urolithiasis. This study reports socio-economic factors, medical history and chemical composition of urinary stones in 976 infants of up to 2 years of age. Between 1992 and 2016, 976 infants presented to our institute with 1038 stones. Chemical composition of stones was analyzed by Fourier transformation infrared spectroscopy (FTIR). The mean age of infants was 19.5 ± 5.74 months with a M:F ratio of 5.5:1. Half (50%) of the infants were rural dwellers, 90% belonged to low socio-economic class and 70% were malnourished. A history of chronic diarrhoea was reported in 13% and urinary tract infections in 5%. The anatomic location was bladder in 487 (46.9%), kidney in 246 (23.6%), ureter in 142 (13.6%), urethra in 2 (0.2%) and 161 (15.5%) were passed spontaneously. Overall frequency of compounds in stones showed ammonium acid urate (AAU) in 772 (74.37%), calcium oxalate (CaOx) in 410 (39.5%). Uric acid (UA) in 119 (11.46%), calcium phosphate apatite (CaP) in 96 (9.25%), magnesium ammonium phosphate (Struvite) in 45 (4.34%), cystine in 12 (1.16%) and xanthine in 40 (3.85%). Frequency of compounds was similar in genders. Infants of age 0-6 months had higher frequency of UA (28%), CaOx (50%) and low AAU (61%) as compared to 11, 39 and 75%, respectively, in 7-24 months (p < 0.049) (p < 0.002) (p < 0.001). Nucleus of stones showed pure AAU in 63 and 43% on the surface due to addition of CaOx, struvite and CaP. Our study has shown that AAU is a major component of stones in infants where the main risk factors are poverty, malnutrition, diarrheal diseases and dehydration.

The goal of this study was to investigate metabolic risk factors in pediatric stone formers in an emerging economy. A prospective, data collection enrolled 250 children age <1-15 years at our center. Risk factors were evaluated by gender and in age groups <1-5, 6-10 and 11-15 years. Patients were evaluated for demographics, blood and 24 h urine for calcium, magnesium, phosphate, uric acid, electrolytes and additional protein, citrate, ammonia and oxalate in urine. All reported values were two sided and statistical significance was considered at p value ≤0.05. The mean age at diagnosis was 7.50 ± 3.56 years with a male to female ratio of 1.84:1. A family history of urolithiasis was found in 41 (16.4 %), urinary tract infection in 18 (7 %) and chronic diarrhea in 75 (30 %). Hypercalcemia was seen in 37 (14.8 %), hyperuricemia in 23 (9.2 %) and hyperphosphatemia in 6 (2.4 %). Urinary metabolic abnormalities were identified in 248 (98 %) of the cases. Hypocitraturia was found in 207 (82.8 %), hyperoxaluria in 62 (26.4 %), hyperuricosuria in 82 (32.8 %), hypercalciuria in 51 (20.4 %), hyperphosphaturia in 46 (18.4 %), hyperammonuria in 10 (4 %), hypocalciuria in 82 (32.8 %), and hypovolemia in 73 (29.2 %). Risk factors were similar between genders except higher rates of hyponatriuria, hypophosphaturia, and hypocalciuria in females. Hyperuricosuria, hyponatriuria, and hypovolemia were highest in 1-5 years (52, 49, 49 %) as compared to (18, 21, 12 %) those in 11-15 years (p < 0.001), respectively. This study shows that careful metabolic analysis can identify risk factors in 98 % of the children where appropriate metaphylaxis can be undertaken both for treatment and prevention of recurrence.