Addition of Different Biochars as Catalysts during the Mesophilic Anaerobic Digestion of Mixed Wastewater Sludge

Biochar (BC) recently gained attention as an additive for anaerobic digestion (AD). This work aims at a critical analysis of the effect of six BCs, with different physical and chemical properties, on the AD of mixed wastewater sludge at 37 °C, comparing their influence on methane production and AD kinetics. AD batch tests were performed at the laboratory scale operating 48 reactors (0.25 L working volume) for 28 days with the addition of 10 g L−1 of BC. Most reactors supplemented with BCs exhibited higher (up to 22%) methane yields than the control reactors (0.15 Nm3 kgVS−1). The modified Gompertz model provided maximum methane production rate values, and in all reactors the lag-phase was equal to zero days, indicating a good adaptation of the inoculum to the substrate. The potential correlations between BCs’ properties and AD performance were assessed using principal component analysis (PCA). The PCA results showed a reasonable correlation between methane production and the BCs’ O–C and H–C molar ratios, and volatile matter, and between biogas production and BCs’ pore volume, specific surface area, and fixed and total carbon. In conclusion, the physic-chemical properties of BC (specifically, hydrophobicity and morphology) showed a key role in improving the AD of mixed wastewater sludge

One year of FBG-based thermo-hygrometers in operation in the CMS experiment at CERN

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The prognostic role of baseline CEA and CA 19-9 values and their time-dependent variations in advanced colorectal cancer patients submitted to first-line therapy.

Serum marker evaluation is an easily available prognostic indicator that may help clinicians to discriminate patients with an aggressive disease; there are few and small-sized studies exploring the prognostic role of baseline carcinoembryonic antigen (CEA) values and their variations during first-line therapy, and even fewer data are available for carbohydrate antigen 19-9 (CA 19-9). Our aim was to analyze the role of those prognostic markers to exploit them in daily clinical practice. Data of 892 patients with marker determination before and 3 and/or 6 months during therapy were extracted from two institutional databases. Patients were grouped according to single marker variation as always negative (G0), decreasing (G1), stable (G2), or increasing (G3). We evaluated the progression-free survival (PFS) and the overall survival (OS) of all the patents and correlated them with CEA and CA 19-9 values. A concordance between response to therapy and marker decrease was evident in 50.2% and in 34.4% of the patients for CEA and CA 19-9. Patients with low CEA or CA 19-9 baseline values had a longer PFS (15.1 vs. 10.5; 13.6 vs. 10.2 months) and OS (32.0 vs. 22.3; 30.5 vs. 20.1 months). The same results of PFS and OS were obtained by analyzing the data of the four different groups. Multivariate analyses confirmed the independent prognostic role of CEA and CA 19-9. Baseline CEA and CA 19-9 levels and their kinetics demonstrated to be independent prognostic factors. CA 19-9 dosage is not recommended; a possible role of CA 19-9 in patients with negative CEA could be worth further evaluation

Review of biochar application in anaerobic digestion processes

Among a wide variety of promising uses, in recent years the possibility of using biochar (BC) as additive to improve anaerobic digestion (AD) processes has attracted a growing interest. AD is a well-established biochemical process converting biomasses into biogas, a renewable energy source that can be directly used in heating and power generation rather than upgraded to bio-methane. Further, digestate (i.e. AD solid residue) could be valorised as soil improver. However, despite a growing number of full-scale biogas plants in Europe, (from about 6,200 in 2009 to 17,600 in 2016, according to European Biogas Association), some challenges limiting optimal AD performances still exist. They mainly include risks of acidification and/or potential inhibition of methanogenesis, hazards of atmospheric and water pollution derived from digestate addition to soil, as well as high energetic and economic costs for cleaning and upgrading of biogas. Thereby, many inorganic and carbonaceous additives have been investigated to stabilize AD and enhance methane production. Among them, BC is cost-effective and doesn’t need to be separated from digestate at the end of the AD process. Actually BC can improve digestate quality in terms of nutrients retention, increase of carbon to nitrogen ratio and reduction of nutrient leaching to soil. In addition, BC production and AD do not appear as competing processes, since biomasses with high lignocellulosic and low moisture contents, optimal for BC generation, are scarcely biodegradable during AD. Although a growing number of studies has verified the possibility of increasing methane production by BC addition during AD, to date, a clear comprehension of potential interactions between BC and AD process has not been fully reached. Since BC can be produced with a wide variety of physico-chemical properties adapted to specific applications, a proper knowledge of these mechanisms and of the related BC properties represent crucial issues. Therefore, the present study aimed to: 1. analyse the mechanisms by which BC would counteract some of the main AD limitations; 2. to perform an economic and environmental assessment of BC production and application in AD. Around 200 studies were selected and analysed by means of an extensive literature review on Science Direct, Scopus, and other scientific databases. Based on the analysis of the reviewed literature, it can be observed that the positive influence of BC on AD processes may act through different potential mechanisms: (1) increase of the buffering capacity of the AD system; (2) mitigation of potential inhibitors (NH3/NH4+ and others); (3) acting as a support medium for biomass immobilization and acclimation; (4) promotion of interspecies electron transfer between microbial populations; (5) enhancement of digestate quality; (6) in-situ biogas cleaning and upgrading (depletion of CO2 and H2S). In general, some of the key properties of BC for the above-mentioned mechanisms are high alkalinity, adequate sorption capacity for specific compounds, high surface area and porous structure able to promote microbial population immobilization and inhibitors’ adsorption, varied functional groups and superficial chemical properties, large electrical conductivity and electron exchange capacity. The economic and environmental analysis suggested that BC environmental applications are encouraged by the net mitigation of carbon emissions; while the economic feasibility of BC production could be linked to the promising energy content of lignocellulosic feedstocks. Further, the environmental benefits related to BC application to AD processes can be synergistically improved by coupling the use of BC derived from lignocellulosic feedstocks to the carbon neutral AD to optimize biogas productio

Gonadal Function in Male Patients With Metastatic Renal Cell Cancer Treated With Sunitinib

Background/aim: Single-agent tyrosine kinase inhibitors are still prescribed as first-line treatment to a relevant subgroup of patients with metastatic renal cell carcinoma (mRCC). These agents are known to cause disfunction of many endocrine glands (e.g., thyroid). In this two-step trial, we aimed to assess gonadal function among male patients with mRCC treated with sunitinib. Patients and methods: We enrolled a first cross-sectional cohort of pre-treated (>6 months) patients and a subsequent cohort of treatment-naïve patients who were prospectively followed-up. All patients were screened for hypogonadism and received a Functional Assessment of Cancer Therapy - General (FACT-G) questionnaire at study entry and after 6 months of therapy. Patients who were candidates for testosterone replacement therapy (TRT) also received a FACT-G questionnaire at baseline and 3 months after supplementation. Results: Among the 30 enrolled patients, the prevalence of hypogonadism was found to be higher in those receiving sunitinib for a longer period (27.3% at baseline, 41.7% in the first 6 months, and 68.4% after 9 months of therapy). The testosterone level of patients correlated with quality of life (R=0.32). A total of six patients received TRT, with a significant improvement in their global quality of life after the first 3 months of treatment. Conclusion: An increasing prevalence of hypogonadism was seen among male patients who received long-term treatment with sunitinib. TRT was associated with relevant improvements in quality of life. These findings corroborate similar published observations and encourage the assessment of gonadal function in male patients with mRCC under treatment with sunitinib