Stability of Anticoagulation Following Acenocoumarin in Stroke Patients: Role of Pharmacogenomics and Acquired Factors.

OBJECTIVE: Pharmacogenomics plays an important role in drug metabolism. A stable anticoagulation is important for primary and secondary prevention of cardioembolic stroke and cerebral venous sinus thrombosis (CVST). We report the role of cytochrome P450 ( CYP2C9*2/*3 ) and vitamin K epoxide reductase subunit 1 ( VKORC1 ) genotypes and acquired causes in maintaining stability of anticoagulation following acenocoumarin in cardioembolic stroke and CVST. METHODS: The study comprised 157 individuals with cardioembolic stroke and CVST who were on acenocoumarin. Their comorbidities, comedication, and dietary habits were noted. Prothrombin time and international normalized ratio (INR) were measured during follow-up, and the coagulation status was categorized as stable (>50% occasions in therapeutic range) and unstable (>50% below and above therapeutic range). Genotyping of VKORC1 , CYP2C9*2 , and CYP2C9*3 was done by polymerase chain reaction-restriction fragment length polymorphism. Bleeding and embolic complications were noted. The predictors of unstable INR were evaluated using multivariate analysis. RESULTS: INR was stable in 47.8% and unstable in 52.2% of patients. Patients with mutant genotypes required low dose of acenocoumarin. The predictors of unstable INR were metallic valve (odds ratio [OR] 4.07, 95% confidence interval [CI] 1.23-13.49, P = 0.02), use of digoxin (OR 0.031, 95% CI 0.13-0.74, P = 0.09), proton pump inhibitor (OR 0.23, 95% CI 0.06-0.91, P = 0.037), sodium valproate (OR 0.22, 95% CI 0.05-0.85, P = 0.029), and CYP2C9*2 genotype (OR 5.57, 95% CI 1.19-26.06, P = 0.02). CONCLUSIONS: Variant genotypes of VKORC1 , CYP2C9*2 , and CYP2C9*3 required lower dose of acenocoumarin, and CYP2C9*2 was associated with unstable INR. Comedication is a modifiable risk factor that needs attention.

Determinants of body weight changes during Ramadan fasting in India amid COVID-19: A cross-sectional study.

Ramadan intermittent fasting (RIF) presents unique challenges and opportunities for public health and clinical practice, especially in populations with a high prevalence of non-communicable diseases. This study aims to investigate the impact of RIF on weight change among Indian Muslims and explore the associated demographic, dietary, and behavioral factors. A cross-sectional survey was conducted with a sample of Indian Muslim adults who observed RIF. Participants were asked to report their demographic information, family and personal health history, and dietary and lifestyle behaviors before and during Ramadan month. The primary outcome was body weight change, with secondary outcomes including changes in dietary patterns, physical activity, and other health-related lifestyle behaviors. The study found that during Ramadan, nearly half of the participants (48.5%) self-reported a retained initial weight, while a significant fraction (30.9%) self-reported a modest weight reduction between 0.5 to 2.5 kg at the end of Ramadan. Additionally, self-reported eating practices demonstrated moderately altered by about half (48.4%) of the study participants, with 32.2% reporting minor changes and 8.2% indicating substantial changes. An urban residence was associated with a higher likelihood of weight gain, where urban residents showed 3 times the odds of increased weight compared to rural inhabitants. Employment status emerged as a significant determinant for weight fluctuation, influencing both weight gain and loss. During Ramadan, there was a significant rise in snacking frequency, increasing from 21.7% to 32.6% in comparison with pre-Ramadan. The consumption of large quantities of food more frequently grew from 14.9% to 36%, and the incidence of eating despite not being hungry went up from 17.4% to 33.2%. The study demonstrates that RIF is associated with variable changes in body weight among adult Indian Muslims, influenced by urbanization, employment status, and dietary changes. The findings suggest that clinicians should provide tailored advice about body weight regulation during Ramadan and consider integrating community-based health initiatives within religious settings to improve health outcomes.

Healing wounds, defeating biofilms: Lactiplantibacillus plantarum in tackling MRSA infections.

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) infections are well-known hospital-borne infections and are a major contributing factor to global health concerns of antimicrobial resistance due to the formation of biofilms. Probiotics are known to assist in the healing of wounds through immunomodulation and also possess anti-pathogen properties via competitive inhibition. The probiotic bacterium, Lactiplantibacillus plantarum MTCC 2621 and its cell-free supernatant (Lp2621) have previously been reported to have antibacterial, excellent antioxidant, and wound healing activity in in vitro conditions and wounds contaminated with S. aureus in mice. Methods: In the current study, we evaluated its anti-MRSA, biofilm inhibition and eradication efficacy, immunomodulatory activity in THP-1 cells, and wound healing potential in wounds contaminated with MRSA infection in mice. Results: In agar well diffusion assay, Lp2621 showed anti-MRSA activity and revealed dose-dependent inhibition and eradication of biofilm by crystal violet assay as well as by Confocal Scanning Laser Microscopy (CLSM) analysis. Further, Lp2621 showed immunomodulatory activity at varied concentrations as measured by IL-6 and IL-10 gene expression in THP-1 cells. Similar findings were observed in serum samples of mice after treatment of excision wound contaminated with MRSA infection by Lp2621 gel, as evident by expression of IL-6 (pro-inflammatory) and IL-10 (anti-inflammatory) cytokines. Conclusions: Overall, our results show that Lp2621 has potent anti-MRSA and antioxidant properties and can prevent and eliminate biofilm formation. It also showed promise when applied to mice with MRSA-infected wounds.

A clinico-radiological study of deep cerebral venous thrombosis.

PURPOSE: Isolated deep cerebral venous thrombosis (DCVT) may have different presentation and outcome compared to DCVT with additional sinus thrombosis. We compare clinico-radiological findings and outcomes of patients with isolated DCVT with those having additional sinus thrombosis. METHODS: Forty-one DCVT patients with or without additional sinus thrombosis were included. Deep CVT was diagnosed if there was thrombosis of straight sinus, vein of Galen, internal cerebral vein, or basal vein of Rosenthal on MR venography (MRV). Isolated DCVT patients were classified as Group A and those with additional sinus thrombosis as Group B. The clinical features, risk factors, MRI findings, and outcomes at 1, 3, and 6 months were compared between Groups A and B. RESULTS: Median age was 28 years, and 22 (54%) were females. Eight (19.5%) patients were in Group A and 33 (80.5%) in Group B. Group B patients had shorter duration of illness (7 vs 30 days; p = 0.01), frequent vomiting [25 (75.7%) vs 2 (25%); p = 0.01], and papilledema [13 (39%) vs 0 (0%); p = 0.04]. Risk factors were comparable. MRI revealed bilateral thalamic [5 (62.5%) vs 6 (18.2%)] and basal ganglia [(4 (50%) vs 6 (18.2%)] lesions more frequently in Group A. At 1 month, 2 (6%) patients died in Group B and none in Group A, and 24 had good outcome (50% Group A and 60.6% in Group B). At 3 months, 30 had good outcome (62.5% Group A and 80.6% in Group B). Improvement after 3 months was negligible. CONCLUSION: Isolated DCVT is rare, and additional sinus thrombosis is associated with more severe illness and death. However, long-term outcomes in the survivors are similar between the two groups.

Cranial fibrous dysplasia: An institutional experience and review of the literature.

BACKGROUND: Cranial or craniofacial fibrous dysplasia (CFD) is a rare entity which most often presents with either incidental finding or with pain/cosmetic disfigurement or visual/hearing problems. Multidisciplinary treatment with close follow-up or medical management/surgery is options. Management of these lesions can often give satisfying results. There is a dearth of neurosurgical literature on this subject matter. Our objective was to review the clinical symptomatology and outcome of CFD patients managed in our institution. METHODS: This is a retrospective observational study of CFD patients managed in our institution over a period of 5 years. Clinical and radiological data were collected from departmental database. Outcomes were evaluated immediately and on 1-4 years follow-up. RESULTS: A total of 21 patients were managed over a period of 5 years with age ranging from 12 to 55 years and symptoms of cosmetic issues or visual disturbance. Preoperative computed tomography scan with 3D reconstruction with bone window was done in all patients. In most of the patients (16/20), immediate reconstruction was done following excision. Five patients were managed conservatively. Follow-up was obtained over a period ranging from 1 to 4 years and all (except one) patients are doing well. Only one patient had permanent visual impairment in spite of early intervention. CONCLUSION: Craniofacial dysplasia has various modalities of management. Careful selection of patients for surgical or conservative management is feasible with good results both in short and long term.

Insight Into the Beneficial Role of Lactiplantibacillus plantarum Supernatant Against Bacterial Infections, Oxidative Stress, and Wound Healing in A549 Cells and BALB/c Mice.

Lactiplantibacillus plantarum MTCC 2621 is a well-characterized probiotic strain and is reported to possess many health benefits. However, the wound healing potential of this probiotic is yet to be explored. Here, we have assessed the antibacterial, antioxidant, and wound healing activities of cell-free supernatant of Lactiplantibacillus plantarum MTCC 2621 (Lp2621). Lp2621 exhibited excellent antibacterial activity against the indicator bacteria in the agar well diffusion assay. Lp2621 did not show any hemolytic activity. The safety of Lp2621 gel was established using the skin irritation assay in BALB/c mice, and no dermal reactions were observed. The supernatant showed 60-100% protection of A549 cells against H2O2-induced stress. In the scratch assay, Lp2621 accelerated wound healing after 24 h of treatment. The percent wound healing was significantly higher in cells treated with Lp2621 at 18-24 h posttreatment. In an excision wound healing in mice, topical application of Lp2621 gel showed faster healing than the vehicle- and betadine-treated groups. Similar wound healing activity was observed in wounds infected with Staphylococcus aureus. Histological examination revealed better wound healing in Lp2621-treated mice. Topical treatment of the wounds with Lp2621 gel resulted in the upregulation of pro-inflammatory cytokine IL-6 in the early phase of wound healing and enhanced IL-10 expression in the later phase. These findings unveil a protective role of Lp2621 against bacterial infection, oxidative stress, and wound healing.

Impact of anticoagulation status on recanalization and outcome of cerebral venous thrombosis.

Effective anticoagulation status may determine the recanalization and outcome of cerebral venous thrombosis (CVT). We report impact of anticoagulation status on recanalization and outcome of CVT. This is a retrospective study on 126 patients with CVT diagnosed on magnetic resonance venography (MRV). Their clinical features and risk factors were noted. The data were retrieved from a prospectively maintained registry, and international normalized ratio (INR) was noted after discharge till 3 months. All the patients were on acenocoumarol. Based on INR value, patients were categorized as Group A (effective anticoagulation INR within the therapeutic range or above) and Group B (ineffective anticoagulation INR > 50% below the therapeutic range). A repeat MRV at 3 months was done for recanalization. Outcome at 3 months was evaluated using modified Rankin Scale (mRS), and categorized as good (mRS ≤ 2) and poor (mRS 2 or more) 101(80.2%) patients were in group A and 25(19.8%) in group B. Their demographic, risk factors, magnetic resonance imaging (MRI) and MRV findings were comparable. On repeat MRV, recanalization occurred in 22/24(91.7%); 15(88%) in group A and 7(100%) in group B. Recanalization was independent of coagulation status. Seven (5.6%) patients died and 107(84.9%) had good outcome; 85(84.2%) in group A and 22(88%) in group B. Kaplan Meier analysis also did not reveal survival or good outcome benefits between the groups. In CVT, outcome and recanalization at 3 months are not dependent on coagulation status. Further prospective studies are needed regarding duration of anticoagulant and its impact on recanalization and outcome.

The novel galactosyl transferase-like (SbGalT) gene from Salicornia brachiata maintains photosynthesis and enhances abiotic stress tolerance in transgenic tobacco.

We hereby report in planta function characterization of a novel galactosyl transferase-like (SbGalT) gene from Salicornia brachiata for enhanced abiotic stress tolerance. The SbGalT gene had an open reading frame of 1563 bp. The ectopic expression of SbGalT gene in tobacco improved the seed germination, seedling growth, biomass accumulation and potassium/sodium ratio under salt and osmotic stress. The SbGalT over-expression delayed stress-induced senescence, pigment break-down and ion induced cytotoxicity in tobacco. Higher contents of organic solutes and potassium under stress maintained the osmotic homeostasis and relative water content in tobacco. Higher activity of antioxidant enzymes under stress in transgenic tobacco curtailed the accumulation of reactive oxygen species (ROS) and maintained the membrane integrity. The chlorophyll a fluorescence transient indicated no effects of the imposed strengths of stress on basal state of photosystem (PS) I in transgenic tobacco over-expressing the SbGalT gene. Due to improved membrane integrity, the transgenic tobacco exhibited improved photosynthesis, stomatal conductance, intercellular CO2, transpiration, maximum quantum yield and operating efficiency of PSII, electron transport, photochemical and non-photochemical quenching. In agreement with photosynthesis, physiological health, tolerance index and growth parameters, transgenic tobacco accumulated higher contents of sugar, starch, amino acid, polyphenol and proline under stress conditions. The multivariate data analysis exhibited significant statistical distinctions among osmotic adjustment, physiological health and growth, and photosynthetic responses in control and SbGalT transgenic tobacco under stress conditions. The results strongly indicated novel SbGalT gene as a potential candidate for developing the smart agriculture.

Flavonoids: Potential Candidates for the Treatment of Neurodegenerative Disorders.

Neurodegenerative disorders, such as Parkinson's disease (PD), Alzheimer's disease (AD), Amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD), are the most concerning disorders due to the lack of effective therapy and dramatic rise in affected cases. Although these disorders have diverse clinical manifestations, they all share a common cellular stress response. These cellular stress responses including neuroinflammation, oxidative stress, proteotoxicity, and endoplasmic reticulum (ER)-stress, which combats with stress conditions. Environmental stress/toxicity weakened the cellular stress response which results in cell damage. Small molecules, such as flavonoids, could reduce cellular stress and have gained much attention in recent years. Evidence has shown the potential use of flavonoids in several ways, such as antioxidants, anti-inflammatory, and anti-apoptotic, yet their mechanism is still elusive. This review provides an insight into the potential role of flavonoids against cellular stress response that prevent the pathogenesis of neurodegenerative disorders.

Proteotoxicity: A Fatal Consequence of Environmental Pollutants-Induced Impairments in Protein Clearance Machinery.

A tightly regulated protein quality control (PQC) system maintains a healthy balance between correctly folded and misfolded protein species. This PQC system work with the help of a complex network comprised of molecular chaperones and proteostasis. Any intruder, especially environmental pollutants, disrupt the PQC network and lead to PQCs disruption, thus generating damaged and infectious protein. These misfolded/unfolded proteins are linked to several diseases such as Parkinson's disease, Alzheimer's disease, Huntington's disease, and cataracts. Numerous studies on proteins misfolding and disruption of PQCs by environmental pollutants highlight the necessity of detailed knowledge. This review represents the PQCs network and environmental pollutants' impact on the PQC network, especially through the protein clearance system.

Role of Oxidative Stress in Tuberculous Meningitis: a Clinico-Radiological Correlation.

Central nervous system infection may be associated with oxidative stress and may influence clinical severity and outcome. We report oxidative stress markers in the patients with tuberculous meningitis (TBM) and correlate these with clinico-radiological severity and outcome. Fifty-six patients with TBM diagnosed on the basis of clinical, cerebrospinal fluid (CSF), and magnetic resonance (MRI) were included. Plasma glutathione (GSH), total antioxidant capacity (TAC), and malondialdehyde (MDA) were measured in the patients and 55 matched healthy controls. Hospital death was noted. Disabilities at 3 and 6 months were categorized using the modified Rankin Scale (mRS) as poor (mRS > 2) or good (mRS ≤ 2). The patients had lower levels of GSH (1.49 ± 0.49 vs 2.57 ± 0.39 mg/dL, p Ë‚ 0.001) and TAC (0.25 ± 0.17 vs 2.20 ± 0.31 mmol Trolox Eq/L, p Ë‚ 0.001), and higher level of MDA (6.61 ± 1.72 vs 3.09 ± 0.38 nmol/mL, p < 0.001) compared to controls. Total antioxidant capacity correlated with cranial nerve palsy and CSF pleocytosis. Patients with tuberculoma had lower GSH compared to those without. Six patients died in the hospital, and they had lower GSH (p < 0.01) and TAC (p = 0.02) levels compared to those who survived. Thirty-one and 36 patients had a good outcome at 3 and 6 months respectively. The patients with good outcome had higher GSH level.

The Role of Clinical Variables and VKORC1 Polymorphism in Efficacy and Stability of Acenocoumarol in Neurological Patients.

OBJECTIVE: To analyze the clinical importance of VKORC1 polymorphism and its correlation with stability of oral anticoagulation. PATIENTS AND METHODS: In a hospital-based study, the patients on oral anticoagulant (OAC) were included during 2013-2016. The patients received OAC for cardioembolic stroke, cerebral venous sinus thrombosis (CVST), and prevention of deep vein thrombosis (DVT). Demographic, clinical, and neurological findings were recorded. Stability of anticoagulation was determined by percentage of time international normalized ratio (INR) values were in therapeutic range. Time in therapeutic range (TTR) >65% was defined as stable and <65% was defined unstable. VKORC 1 polymorphism was studied by polymerase chain reaction and correlated with daily dose of OAC and stability of INR. RESULTS: A total of 157 patients with a median age of 40 years were included in the study. Ninety-two patients received OAC for secondary stroke prevention, 62 for CVST, and 3 for DVT. Out of 2976 INR reports, 1458 (49%) were in the therapeutic range, 997 (33.1%) were below the therapeutic range, and 521 (17.5%) were above the therapeutic level. Stable INR was obtained in 75 (47.77%) patients which was improved by drug modification in 3 and dietary adjustment in 12 patients. VKORC1 polymorphism revealed GG genotype in 127 (80.9%), GA genotype in 22 (14%), and AA genotype in 8 (5.1%) patients. Therapeutic range of INR was seen in 49%, below therapeutic range was seen in 31.5%, and above in 17.5%. CONCLUSION: VKORC1 polymorphism was related to mean daily dose of OAC but not to the stability of INR.

Environmentally Friendly Plasma-Treated PEDOT:PSS as Electrodes for ITO-Free Perovskite Solar Cells.

Solution processed poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) transparent electrodes (TEs) offer great potential as a low cost alternative to expensive indium tin oxide (ITO). However, strong acids are typically used for enhancing the conductivity of PEDOT:PSS TEs, which produce processing complexity and environmental issues. This work presents an environmentally friendly acid free approach to enhance the conductivity of PEDOT:PSS using a light oxygen plasma treatment, in addition to solvent blend additives and post treatments. The plasma treatment was found to significantly reduce the sheet resistance of PEDOT:PSS TEs from 85 to as low as 15 Ω sq-1, which translates to the highest reported conductivity of 5012 S/cm for PEDOT:PSS TEs. The plasma treated PEDOT:PSS TE resulted in an ITO-free perovskite solar cell efficiency of 10.5%, which is the highest reported efficiency for ITO-free perovskite solar cells with a PEDOT:PSS electrode that excludes the use of acid treatments. This research presents the first demonstration of this technology. Moreover, the PEDOT:PSS TEs enabled better charge extraction from the perovskite solar cells and reduced hysteresis in the current density-voltage (J-V) curves.

Overexpression of SbSI-1, A Nuclear Protein from Salicornia brachiata Confers Drought and Salt Stress Tolerance and Maintains Photosynthetic Efficiency in Transgenic Tobacco.

A novel Salicornia brachiata Salt Inducible (SbSI-1) gene was isolated and overexpressed in tobacco for in planta functional validation subjected to drought and salt stress. SbSI-1 is a nuclear protein. The transgenic tobacco overexpressing SbSI-1 gene exhibited better seed germination, growth performances, pigment contents, cell viability, starch accumulation, and tolerance index under drought and salt stress. Overexpression of SbSI-1 gene alleviated the build-up of reactive oxygen species (ROS) and curtailed the ROS-induced oxidative damages thus improved the physiological health of transgenic tobacco under stressed conditions. The higher activities of antioxidant enzymes, lower accumulation of ROS, higher membrane stability, relative water content, and polyphenol contents indicated the better survival of the transgenic tobacco than wild-type (WT) tobacco under stressed conditions. Transgenic tobacco had a higher net photosynthetic rate, PSII operating efficiency, and performance index under drought and salt stress. Higher accumulation of compatible solutes and K+/Na+ ratio in transgenic tobacco than WT showed the better osmotic and redox homeostasis under stressed conditions. The up-regulation of genes encoding antioxidant enzymes (NtSOD, NtAPX, and NtCAT) and transcription factors (NtDREB2 and NtAP2) in transgenic tobacco under stressed conditions showed the role of SbSI-1 in ROS alleviation and involvement of this gene in abiotic stress tolerance. Multivariate data analysis exhibited statistical distinction among growth responses, physiological health, osmotic adjustment, and photosynthetic responses of WT and transgenic tobacco under stressed conditions. The overexpression of SbSI-1 gene curtailed the ROS-induced oxidative damages and maintained the osmotic homeostasis under stress conditions thus improved physiological health and photosynthetic efficiencies of the transgenic tobacco overexpressing SbSI-1 gene.

Shelf life stability comparison in air for solution processed pristine PDPP3T polymer and doped spiro-OMeTAD as hole transport layer for perovskite solar cell.

This data in brief includes forward and reverse scanned current density-voltage (J-V) characteristics of perovskite solar cells with PDPP3T and spiro-OMeTAD as HTL, stability testing conditions of perovskite solar cell shelf life in air for both PDPP3T and spiro-OMeTAD as HTL as per the description in Ref. [1], and individual J-V performance parameters acquired with increasing time exposed in ambient air are shown for both type of devices using PDPP3T and spiro-OMeTAD as HTL. The data collected in this study compares the device stability with time for both PDPP3T and spiro-OMeTAD based perovskite solar cells and is directly related to our research article "solution processed pristine PDPP3T polymer as hole transport layer for efficient perovskite solar cells with slower degradation" [2].

Crystallization of a perovskite film for higher performance solar cells by controlling water concentration in methyl ammonium iodide precursor solution.

An optimal small amount of water added into methyl ammonium iodide (MAI) solution in isopropyl alcohol (IPA) helps perovskite crystallization and leads to larger grain size from sequential deposition of perovskite films. The concentration of water was varied from 1% to 7% (vol% of IPA) in MAI solution and optical absorption, crystallization, morphology of perovskite films and their photovoltaic performance were studied in perovskite solar cells. 5% by volume was found to lead to preferential crystallization in the (110) plane with grain size about three times that of perovskite films prepared without adding water into the MAI solution. The optimal water concentration of 5% by volume in the MAI solution led to average perovskite grain size of ∼600 nm and solar cell efficiency of 12.42% at forward scan with a rate of 0.5 V s(-1). Device performance decreases after increasing water concentration beyond 5% in the MAI solution due to formation of the PbI2 phase. Transient photocurrent and photovoltage measurements show the shortest charge transport time at 0.99 µs and the longest charge carrier life time at 13.6 µs for perovskite films prepared from 5% water in MAI solution, which improved perovskite solar cell efficiency from 9.04% to 12.42%.

Interfacial Study To Suppress Charge Carrier Recombination for High Efficiency Perovskite Solar Cells.

We report effects of an interface between TiO2-perovskite and grain-grain boundaries of perovskite films prepared by single step and sequential deposited technique using different annealing times at optimum temperature. Nanoscale kelvin probe force microscopy (KPFM) measurement shows that charge transport in a perovskite solar cell critically depends upon the annealing conditions. The KPFM results of single step and sequential deposited films show that the increase in potential barrier suppresses the back-recombination between electrons in TiO2 and holes in perovskite. Spatial mapping of the surface potential within perovskite film exhibits higher positive potential at grain boundaries compared to the surface of the grains. The average grain boundary potential of 300-400 mV is obtained upon annealing for sequentially deposited films. X-ray diffraction (XRD) spectra indicate the formation of a PbI2 phase upon annealing which suppresses the recombination. Transient analysis exhibits that the optimum device has higher carrier lifetime and short carrier transport time among all devices. An optimum grain boundary potential and proper band alignment between the TiO2 electron transport layer (ETL) and the perovskite absorber layer help to increase the overall device performance.

Origin of photogenerated carrier recombination at the metal-active layer interface in polymer solar cells.

The role of the metal-active layer interface in photogenerated recombination has been investigated using nanoscale current sensing atomic force microscopy (CS-AFM) and intensity modulated photocurrent spectroscopy (IMPS) in as-deposited, pre-annealed and post-annealed bulk heterojunction (BHJ) solar cells. Aluminum (Al) confined post-annealed BHJ solar cells exhibited a significantly improved device efficiency compared to pre-annealed BHJ solar cells having similar photocarrier harvesting ability in the active layer. The nanoscale topography and CS-AFM results indicate a uniform PCBM rich phase at the metal-active layer interface in the post-annealed cells, but PCBM segregation in the pre-annealed cells. These two different annealing processes showed different carrier dynamics revealed using IMPS under various light intensities. The IMPS results suggest reduced photo generated carrier recombination in uniform PCBM rich post-annealed BHJ solar cells. This study reveals the importance of the metal-bend interface in BHJ solar cells in order to obtain efficient charge carrier extraction for high efficiency.

Catalytic cracking of non-edible sunflower oil over ZSM-5 for hydrocarbon bio-jet fuel.

Non-edible sunflower oils that were extracted from sunflower residual wastes were catalytically cracked over a ZSM-5 catalyst in a fixed-bed reactor at three different reaction temperatures: 450°C, 500°C and 550°C. The catalyst was characterized using XRD, FT-IR, BET and SEM. Characterizations of the upgraded sunflower oils, hydrocarbon fuels, distillation residues and non-condensable gases were carried out. The effect of the reaction temperature on the yield and quality of liquid products was discussed. The results showed that the reaction temperature affected the hydrocarbon fuel yield but had a minor influence on its properties. The highest conversion efficiency from sunflower oils to hydrocarbon fuels was 30.1%, which was obtained at 550°C. The reaction temperature affected the component content of the non-condensable gases. The non-condensable gases generated at 550°C contained the highest content of light hydrocarbons (C1-C5), CO, CO2 and H2. Compared to raw sunflower oils, the properties of hydrocarbon fuels including the dynamic viscosity, pH, moisture content, density, oxygen content and heating value were improved.

Benzothiadiazole-based polymer for single and double junction solar cells with high open circuit voltage.

Single and double junction solar cells with high open circuit voltage were fabricated using poly{thiophene-2,5-diyl-alt-[5,6-bis(dodecyloxy)benzo[c][1,2,5]thiadiazole]-4,7-diyl} (PBT-T1) blended with fullerene derivatives in different weight ratios. The role of fullerene loading on structural and morphological changes was investigated using atomic force microscopy (AFM) and X-ray diffraction (XRD). The XRD and AFM measurements showed that a higher fullerene mixing ratio led to breaking of inter-chain packing and hence resulted in smaller disordered polymer domains. When the PBT-T1:PC60BM weight ratio was 1 : 1, the polymer retained its structural order; however, large aggregated domains formed, leading to poor device performance due to low fill factor and short circuit current density. When the ratio was increased to 1 : 2 and then 1 : 3, smaller amorphous domains were observed, which improved photovoltaic performance. The 1 : 2 blending ratio was optimal due to adequate charge transport pathways giving rise to moderate short circuit current density and fill factor. Adding 1,8-diiodooctane (DIO) additive into the 1 : 2 blend films further improved both the short circuit current density and fill factor, leading to an increased efficiency to 4.5% with PC60BM and 5.65% with PC70BM. These single junction solar cells exhibited a high open circuit voltage at ∼ 0.9 V. Photo-charge extraction by linearly increasing voltage (Photo-CELIV) measurements showed the highest charge carrier mobility in the 1 : 2 film among the three ratios, which was further enhanced by introducing the DIO. The Photo-CELIV measurements with varying delay times showed significantly higher extracted charge carrier density for cells processed with DIO. Tandem devices using P3HT:IC60BA as bottom cell and PBT-T1:PC60BM as top cell exhibited a high open circuit voltage of 1.62 V with 5.2% power conversion efficiency.