Spatio-temporal variability of Borer Polychaetes in Posidonia oceanica beds and its relation to meadow structure

Posidonia oceanica forms an extremely productive and complex ecosystem in the coastal Mediterranean Sea providing a suitable habitat for hundreds of plant and animal species. Among motile invertebrates associated to Posidonia meadows, polychaete borers of the plant sheaths represent a unique group which exploit a peculiar microhabitat. They belong to the family Eunicidae with three dominant species, Lysidice collaris, L. ninetta and L. unicornis. Due to their strong association with Posidonia shoots, these animals are particularly suitable to study the plant and animal spatial relationships and their pattern of variability. The aim of this work was to evaluate the frequency of occurrence of these animals (Index of Borer, IB) at different spatial and temporal (summer vs winter) scales in two Posidonia meadows off the Ischia Island (Gulf of Naples, Italy), which are exposed to different degrees of human impact and of hydrological conditions. Results showed IB values of L. collaris (the most abundant species) significantly different between meadows and at scales from 10s to 100s of meters, as well as between summer and winter. The IB of L. ninetta showed significant differences only at scales of 10s of meters while, on the contrary, the IB of L. unicornis (the less abundant species) did not show variability at any spatial and temporal scales. Most of the variance was at the more impacted and less water movement exposed meadow, suggesting higher level of small and intermediate scales of patchiness of borers at this meadow. These variation patterns are discussed in relation to local environmental differences between the studied Posidonia beds

Innovative strategy for polyhydroxyalkanoates recovery from mixed microbial cultures. Effects of aqueous phase and solvent extraction on polymer properties

This work aimed to investigate various methods of polyhydroxyalkanoates (PHA) extraction and to optimize the recovery in the view of reducing solvents’ use and waste. The extraction tests were applied on PHA-rich biomass collected at the end of the accumulation step, conducted both at pilot and lab scale. PHA-rich biomass obtained from the lab scale process was produced from synthetic feedstock (mixture of acetic and propionic acids), while fermented organic waste was used for PHA production at pilot scale. In the extraction tests, different solutions of NaOH, also in combination with a surfactant (sodium dodecyl sulfate, SDS), were used to recover the polymer from the non-polymeric cellular material (NPCM). Different times (3, 6 and 24 h) and concentrations (0.05 – 1 M) were tested, evaluating also the effect of adding SDS (0.1 % w/v). As a benchmark, solvent extraction with chloroform and oxidation with NaClO were also conducted. Finally, extracted samples were characterized through several techniques: DSC, TGA, GC-FID, capillary viscosimetry. Alkaline treatment at short times and low concentrations resulted to be more efficient in terms of purity (85 – 99 % w/w PHA) and recovery (higher than 80 % w/w), than higher concentration. On the other hand, the presence of SDS had dramatic effects on the recovery (lower than 50 % w/w) and also on the molecular weight, which was two folds lower than that obtained from alkaline extraction. Overall, extraction with aqueous phase reagents had no effects on thermal properties, which resulted to be in the range of those reported in literature

Hydrogenophilic and bioelectrochemical production of acetate with a pure culture of Acetobacterium Woodii

In recent years there has been a growing interest in the potential use of autotrophic acetogenic bacteria to produce compounds of interest through CO2 fixation, representing an alternative solution to currently used CO2 storage technologies. This group of microorganisms are ubiquitous in nature and they are characterised by a Wood-Ljungdahl pathway that combines CO2 fixation with adenosine triphosphate (ATP) synthesis by using H2 as electron donor. In this work the autotrophic production of acetate by a pure colture of Acetobacterium woodii has been tested under hydrogenophilic or bioelectrochemical conditions. More in details, the hydrogenophilic tests were conducted at two different pH values (5.5 and 7.5) with an H2 partial pressure of 0.52 atm, while bioelectrochemical tests were performed at an applied cathodic potential of -0.90 V vs. SHE (Standard Hydrogen Electrode). The bioelectrochemical tests were set up in H-type reactors (250 mL), in which graphite rods were used as electrodic material and an anion exchange membrane served to separate the anodic and cathodic chambers while allowing anions migration for electroneutrality maintenance. The hydrogenophilic tests resulted in different kinetics depending on the applied pH value. The bioelectrochemical tests, performed at a pH value of 7.5, reached an acetate production rate 2 times higher than in the hydrogenophilic experiments at pH 7.5, as well as an increase in the efficiency of using the reducing power, suggesting an improvement in hydrogen uptake. At pH 5.5, on the other hand, production is improved by increasing the partial pressure of H

Modelling Mixed Microbial Culture Polyhydroxyalkanoate Accumulation Bioprocess towards Novel Methods for Polymer Production Using Dilute Volatile Fatty Acid Rich Feedstocks

Volatile fatty acid (VFA) rich streams from fermentation of organic residuals and wastewater are suitable feedstocks for mixed microbial culture (MMC) Polyhydroxyalkanoate (PHA) production. However, many such streams have low total VFA concentration (1–10 gCOD/L). PHA accumulation requires a flow-through bioprocess if the VFAs are not concentrated. A flow through bioprocess must balance goals of productivity (highest possible influent flow rates) with goals of substrate utilization efficiency (lowest possible effluent VFA concentration). Towards these goals, dynamics of upshift and downshift respiration kinetics for laboratory and pilot scale MMCs were evaluated. Monod kinetics described a hysteresis between the upshift and downshift responses. Substrate concentrations necessary to stimulate a given substrate uptake rate were significantly higher than the concentrations necessary to sustain the attained substrate uptake rate. A benefit of this hysteresis was explored in Monte Carlo based PHA accumulation bioprocess numerical simulations. Simulations illustrated for a potential to establish continuous flow-through PHA production bioprocesses even at a low (1 gCOD/L) influent total VFA concentration. Process biomass recirculation into an engineered higher substrate concentration mixing zone, due to the constant influent substrate flow, enabled to drive the process to maximal possible PHA production rates without sacrificing substrate utilization efficiency

Production of short-chain fatty acid from CO2 through mixed and pure culture in a microbial electrosynthesis cell

The continuous accumulation of atmospheric CO2 requires the development of new technologies for its mitigation. Carbon capture and utilization (CCU) technologies aim to convert CO2 into precious compounds like chemicals and fuels. Biological fixation is an attractive CCU strategy in terms of cost, sustainability and variety of products. Chemoautotrophic microorganisms such as methanogens and acetogens are able to reduce CO2 into acetate and methane, respectively. Acetogens bacteria are able to use CO2 for cell growth through the Wood Liujhundal pathway, moreover, the final precursor (i.e. Acetyl-CoA) of the autotrophic metabolism, is also used in energy metabolism with acetate production as a waste product. Furthermore, it is possible to obtain multicarbon products of autotrophic origin starting from acetyl-CoA and acetate. The biotechnological use of these microorganisms requires the presence of H2 as substrate, which is used as an electron donor in the pathway. This reaction can be sustained by a biocathode in a microbial electrosynthesis cell, in which the reducing power is generated by a polarized electrode. This study proposes the use of a microbial electrosynthesis cell for conversion to acetate in H-cells by either a mixed culture enriched with Acetobacterium woodii or a pure culture of Acetobacterium woodii, to observe the difference in terms of acetate production and reducing power consumption efficiency. The mixed culture was obtained from a mixture of activated sludge and anaerobic digestate, treated by a protocol capable to select acetogenic microorganisms without the use of specific chemical inhibitors (2-Bromoethanesulfonate). Both inoculums were tested at room temperature (25°C) in the cathodic chamber of the H-cell at potentials in the range of -0.7 to -1.1 V vs SHE. The obtained results showed that the enriched mixed culture produced at -0.7 vs SHE a mixture of volatile fatty acids including C4 and C5 molecules with an overall coulombic efficiency of 50%, while at the potential of -0.9 vs SHE methane constituted the main product of the biocathode. The pure culture, on the other hand, showed a specific production of acetate with a coulombic efficiency of 44% at -0.9 vs SHE and 63% at -1.1 vs SHE. Furthermore, a drastic decrease in biocathode biomass was observed in pure culture, suggesting a higher tendency to form biofilms on the electrode unlike the mixed culture, which showed a standard growth profile in the bulk

Acetogenic inoculum selection for acetate production from waste biomasses via thermal shock treatment

Innovative treatment and utilization of waste biomass streams are crucial for increase environmental sustainability of human activities. Sewage sludge from the biological degradation of biomass can be valorized for the selection of biocatalysts capable to convert CO2 into valuable products. Indeed, chemoautotrophic microorganisms, like methanogens and acetogens, respectively, are able to convert CO2 into CH4 or acetate by using hydrogen as electron donor, i.e., their utilization for several bio-based CO2 reutilization processes has been widely proposed by several authors. Chemoautothrophic acetogens are widely present in waste streams deriving from the organic matter degradation, however, due to the syntrophic relationship between acetogens and acetoclastic methanogens in anaerobic environments, autothropihc acetate results immediately converted into methane. Therefore, the selection of an acetogenic inoculum which allow to obtain CO2 reduction into acetate, requires methanogens inhibition. Among the different methanogen’s inhibition strategies, the most common method is the use of BES (bromo-ethane sulphonate) which results a not scalable technique for large scale application. A most promising and sustainable approach is offered by the adoption of a thermal treatment which allows to the selection of an acetogenic inoculum, thanks ot the sporogenous capacity of acetogenic bacteria. This work presents the results obtained in the thermal pre-treatment of different type of waste biomasses coming from pilot and full-scale biological processes for the selection of an acetogenic inoculum able to convert CO2 into acetate. Each waste biomass was treated by a thermal shock procedure that consisted in the treatment of the dried biomass at 120°C for 2 hours. Acetogenic inoculums obtained by the thermal pre-treatment of an acidogenic fermentate, an activated sludge and a mesophilic anaerobic digestate, were tested under hydrogenophilic conditions in comparison with blank tests and raw inoculums. The results clearly indicate the effectiveness of the thermal pre-treatment in the selection of the acetogenic microorg

Demographics, Patterns of Care, and Survival in Pediatric Medulloblastoma

We evaluated the American College of Surgeon’s National Cancer Data Base (NCDB) to describe current hospital-based epidemiologic frequency, survival, and patterns of care of pediatric medulloblastoma. We analyzed NCDB 1998–2011 data on medulloblastoma for children ages 0–19 years using logistic and poisson regression, Kaplan–Meier survival estimates, and Cox proportional hazards models. 3647 cases of medulloblastoma in those aged 0–19 years were identified. Chemotherapy was received by 79 and 74% received radiation, with 65% receiving both therapies. Those who received radiation were more likely to be older than four, while those who received chemotherapy were more likely to be age four and younger. Variables associated with receipt of neither radiation nor chemotherapy included age at diagnosis of \u3c 1 year, female gender, being of race other than black or white, having no insurance, and living in a residential area with a low level of high school graduates. Better overall survival was observed as age at diagnosis increased, in females, and having received radiation. Compared to medulloblastoma, NOS, better survival was observed for those with demoplastic medulloblastoma, with worse survival in those with large cell medulloblastoma. Majority received multi- disciplinary therapy and radiation had the greatest effect on survival. Ages four and under were most likely to receive chemotherapy and least likely to receive radiation. Suboptimal treatment included 17.8% that did not receive chemotherapy, of which 11.8% received neither chemotherapy nor radiation. Disparities associated with medical access were characteristics for not receiving standard treatment, which resulted in poor outcome

Geographical Concentration of Rural Poverty in Bangladesh

This paper was presented at the dialogue on Mapping Poverty for Rural Bangladesh: Implications for Pro-poor Development. The dialogue was organised as part of CPD's ongoing agricultural policy research and advocacy activities with IRRI under the PETRRA project. The study reported geographical concentration of rural poverty in Bangladesh for 425 upazilas in 2000-01. The study measured and mapped incidence of poverty (using Headcount Index), intensity of poverty (using Poverty Gap Index) and severity of poverty (using Squared Poverty Gap Index). It has analyzed factors contributing to the spatial concentration of poverty. It is hoped that the findings of the study would be helpful in identifying target areas and priorities for agricultural R&D interventions and poverty reduction programmes.Poverty, Rural Poverty, Bangladesh

Polyhydroxyalkanoates production by mixed microbial cultures in sequencing batch reactors operated under different feeding conditions

The production of polyhydroxyalkanoates (PHA) by mixed microbial cultures (MMC) requires a multistage process, whereby the microbial selection of PHA-storing microorganisms plays a key role on the overall performance. A strategy to favor the microbial selection consists in the alternance of excess (feast phase) and absence (famine phase) of the external carbon source. In this work, three runs of a lab-scale Sequencing Batch Reactor (SBR) operated under different working conditions for the establishment of the feast and famine (F/F) regime were analyzed. A fixed organic loading rate of 4.25 gCOD (Chemical Oxygen Demand)/L d, and a fixed cycle length of 12 h were applied to the SBR. The F/F regime consisted of fully aerobic dynamic (ADF) or aerobic/anoxic (AE/ANOX) conditions. Results showed an intracellular PHA content as high as 40 ± 2 (%, w/w) when ADF conditions were applied with the organic feeding solution made of acetate (85 % on COD basis) and propionic (15%) acids. The hydroxyvalerate content in the stored polymer increased (from 25 ± 1 to 41 ± 3, % w/w) by increasing the propionic fraction (up to 35%) in the feeding solution. The AE/ANOX condition resulted in a lower PHA-storing ability which warrants further investigations

Multimodality Therapy Improves Survival in Intramedullary Spinal Cord Metastasis of Lung Primary

Background: Most metastatic spinal cord lesions are located either in the intradural, extramedullary, or in the epidural compartments. Intramedullary spinal cord metastasis (ISCM) is a rare central nervous system spread of cancer. The aim of this report was to evaluate ISCM in the published literature. Methods: A literature review of PubMed from 1960 to 2016 was undertaken for the publications having demographic, clinical, histological, and outcome data. Results: A total of 59 relevant papers were identified, showing 128 cases of intramedullary metastasis from lung cancer. The incidence of lung cancer as the primary malignancy with intramedullary metastasis was 56%. The median time from diagnosis of primary to intramedullary metastasis was 6 months. Survival improved with multimodality therapy compared to monotherapy (4 months vs. 6.3 months) (hazard ratio = 0.501; 95% confidence interval, 0.293–0.857). Conclusion: Lung cancer is the predominant cause of intramedullary involvement of the spinal cord. Overall prognosis is poor, although a multimodality approach was associated with improved survival