The race between classical microbial fuel cells, sediment-microbial fuel cells, plant-microbial fuel cells, and constructed wetlands-microbial fuel cells: Applications and technology readiness level.

Microbial fuel cell (MFC) is an interesting technology capable of converting the chemical energy stored in organics to electricity. It has raised high hopes among researchers and end users as the world continues to face climate change, water, energy, and land crisis. This review aims to discuss the journey of continuously progressing MFC technology from the lab to the field so far. It evaluates the historical development of MFC, and the emergence of different variants of MFC or MFC-associated other technologies such as sediment-microbial fuel cell (S-MFC), plant-microbial fuel cell (P-MFC), and integrated constructed wetlands-microbial fuel cell (CW-MFC). This review has assessed primary applications and challenges to overcome existing limitations for commercialization of these technologies. In addition, it further illustrates the design and potential applications of S-MFC, P-MFC, and CW-MFC. Lastly, the maturity and readiness of MFC, S-MFC, P-MFC, and CW-MFC for real-world implementation were assessed by multicriteria-based assessment. Wastewater treatment efficiency, bioelectricity generation efficiency, energy demand, cost investment, and scale-up potential were mainly considered as key criteria. Other sustainability criteria, such as life cycle and environmental impact assessments were also evaluated.

High riding innominate artery: An unusual pulsatile pretracheal mass.

Anterior neck masses are common and such patients commonly present to ultrasonography units for further evaluation of underlying pathology. We encountered an atypical case of pulsatile anterior neck swelling in a 45-year-old lady. Evaluation of the swelling using neck ultrasonography and color doppler study revealed that the mass was of vascular origin and contrast-enhanced computed tomography of neck confirmed the presence of an aberrant high riding innominate artery. Knowledge of such variants is of great importance and should be reported by the concerned radiologist. Lack of knowledge of such variants may lead to inadvertent surgical complications during procedures and can be life-threatening to the patient.

Performance assessment of aeration and radial oxygen loss assisted cathode based integrated constructed wetland-microbial fuel cell systems.

The present study explores low-cost cathode development possibility using radial oxygen loss (ROL) of Canna indica plants and intermittent aeration (IA) for wastewater treatment and electricity generation in constructed wetland-microbial fuel cell (CW-MFC) system. Two CW-MFC microcosms were developed. Amongst them, one microcosm was planted with Canna indica plants for evaluating the ROL dependent cathode reaction (CW-MFC dependent on ROL) and another microcosm was equipped with intermittent aeration for evaluating the intermittent aeration dependent cathode reaction (CW-MFC with additional IA). The CW-MFC with additional IA has achieved 78.71% and 53.23%, and CW-MFC dependent on ROL has achieved 72.17% and 46.77% COD removal from synthetic wastewater containing glucose loads of 0.7gL-1and 2.0gL-1, respectively. The maximum power density of 31.04mWm-3 and 19.60mWm-3 was achieved in CW-MFC with additional IA and CW-MFC dependent on ROL, respectively.

Low temperature growth of ZnO nanotubes for fluorescence quenching detection of DNA.

In this work, large-scale and single-crystalline ZnO nanotubes were fabricated by a simple technique from an aqueous solution at a low temperature of 65 °C. According to detailed morphology, structural and compositional analyses showed that the ZnO nanotubes [diameter ~200 nm (wall thickness ~50 nm); length ~1 µm] have single-crystallite with wurtzite structure. As-prepared ZnO nanotubes showed an effective fluorescence quenching for the detection of calf thymus DNA. In particular, increasing DNA concentrations (5-50 µM) into the fixed concentration of ZnO nanotubes (50 µM) progressively quenched the intrinsic fluorescence of nanotubes, which showed that the nanotubes fluorescence was efficiently quenched upon binding to DNA. At the highest ZnO-DNA molar ratios of 1:1.8, around 50.1 % of fluorescence quenching of DNA was observed. Significance of this study provides simple, cost-effective, and low temperature synthesis of ZnO nanotubes revealed better fluorescence property toward a platform of DNA sensor. ZnO nanotubes with diameter of ~200 nm (wall thickness ~50 nm) and length of about 1 µm prepared at low temperature (65 °C) showed fluorescence was efficiently quenched upon binding to DNA. In particular, around 50.1 % of DNA fluorescence quenching at the highest ZnO-DNA molar ratios of 1:1.8 was observed.

Novel Biomimatic Synthesis of ZnO Nanorods Using Egg White (Albumen) and Their Antibacterial Studies.

Zinc oxide (ZnO) is well-recognized as a biocompatible multifunctional material with outstanding properties as well as low toxicity and biodegradability. In this work, a simple and versatile technique was developed to prepare highly crystalline ZnO nanorods by introducing egg white to a bio-inspired approach. X-ray diffraction (XRD) and selected area electron diffraction (SAED) pattern results indicated that the ZnO nanorods have single phase nature with the wurtzite structure. Field emission scanning electron microscopy (FESEM) and Transmission electron microscopy (TEM) results showed the nanometer dimension of the nanorods. Raman, FTIR, and TGA/DTA analyses revealed the formation of wurtzite ZnO. The antibacterial properties of ZnO nanorods were investigated using both Gram-positive and Gram-negative microorganisms. These studies demonstrate that ZnO nanorods have a wide range of antibacterial activities toward various microorganisms that are commonly found in environmental settings. Survival ratio of bacteria decreased with increasing powder concentration, i.e., increase in antibacterial activity. The antibacterial activity of the ZnO nanorods toward Pseudomonas aeruginosa was stronger than that of Escherichia coli and Staphylococcus aureus. Surprisingly, the antibacterial activity did not require specific UV activation using artificial lamps, rather activation was achieved under ambient lighting conditions. Overall, the experimental results suggest that ZnO nanorods could be developed as antibacterial agents against a wide range of microorganisms to control and prevent the spreading and persistence of bacterial infections. This research introduces a new concept to synthesize ZnO nanorods by using egg white as a biological template for various applications including food science, animal science, biochemistry, microbiology and medicine.

Safety and efficacy of endoscopic dilation for primary and anastomotic Crohn's disease strictures.

BACKGROUND: Literature on endoscopic dilation of Crohn's disease (CD) strictures, especially for primary (non-anastomotic) strictures is limited. METHODS: A historical cohort study was performed on patients who underwent endoscopic stricture dilations for CD in our IBD center. Primary endpoint was the efficacy of first endoscopic dilation in preventing the need for surgery in primary strictures compared to anastomotic strictures. Cox proportional hazards models using robust sandwich covariance matrix estimate were used to evaluate the need for surgery and any further endoscopic intervention. RESULTS: In our study cohort (mean age 42.2 ± 13.1 years, 57% females, 16.4% current smokers, and median follow-up 1.8 years), 128 patients underwent a total of 430 endoscopic stricture dilations for 169 strictures (88 primary, 81 secondary). Forty-two patients (32.8%) required surgery in the follow-up period, with a mean interval period between first dilation and surgery of 33 months. There was no difference between primary or anastomotic strictures with respect to the need for surgery (34.1% vs. 29.6%, p=0.53), redilation (59.1% vs. 58%, p=0.89) or total interventions (surgery+redilations, 71.6% vs. 72.8%, p=0.86). Multivariable analysis did not show any significant difference between patients who received and did not receive intralesional steroid injections, biologics or immunomodulators with respect to the need for repeat intervention or surgery. CONCLUSION: Efficacy and safety of endoscopic dilation are similar between primary and anastomotic CD strictures. Intralesional steroid injection or use of biologics did not decrease the need for re-intervention or surgery for either primary or anastomotic strictures.

Olanzapine and risperidone effects on appetite and ghrelin in chronic schizophrenic patients.

Olanzapine and other second generation antipsychotics have been associated with weight gain, which may be related to changes in appetite and food intake. However, it is unclear whether changes in appetite in response to treatment with second generation antipsychotics are persistent in patients treated chronically with these medications and the extent to which changes in appetite are related to any continuing weight gain associated with long-term treatment with these drugs. In a randomized 5-month study of the effects of olanzapine and risperidone on metabolic changes in chronic schizophrenic patients, we assessed appetite changes using two scales and correlated appetite changes with weight gain and metabolic changes. There is evidence that the hormone ghrelin is related to appetite stimulation and falls during satiation after meals, and therefore, may be a physiological concomitant indicating appetite changes. We therefore, also measured ghrelin before and after a fatty meal at baseline and after 2 months of drug treatment. Neither olanzapine nor risperidone increased appetite during the 5 months of study drug treatment, and there was a trend for a decrease in appetite over time. Weight only increased slightly during treatment and changes in appetite scores were not correlated with changes in weight or changes in glucose or lipids. Fasting ghrelin did not increase in olanzapine- or risperidone-treated patients, and there were no significant changes in ghrelin responses to a fatty meal between baseline and 2 months of drug treatment, and no differences in response in olanzapine- vs. risperidone-treated patients. Our findings suggest that in chronic schizophrenic patients treated with multiple antipsychotics in the past, olanzapine or risperidone do not induce increases in appetite and appetite changes are not related to any further small drug-induced weight gain in these chronically treated patients. However, it is possible that different relationships may exist between appetite and weight changes induced by the medications in drug naive patients newly started on olanzapine or risperidone.