Ammonium recovery from agro-industrial digestate using bioelectrochemical systems.

Growing food and biomass production at the global scale has determined a corresponding increase in the demand for and use of nutrients. In this study, the possibility of recovering nitrogen from agro-industrial digestate using bioelectrochemical systems was investigated: two microbial electrolysis cells (MECs) were fed with synthetic and real digestate (2.5 gNH4+-N L-1). Carbon felt and granular graphite were used as anodes in MEC-1 and MEC-2, respectively. As to synthetic wastewater, the optimal nitrogen load (NL) for MEC-1 and -2 was 1.25 and 0.75 gNH4+-N d-1, respectively. MEC-1 showed better performance in terms of NH4+-N removal efficiency (39 ± 2.5%) and recovery rate (up to 70 gNH4+-N m-2d-1), compared to MEC-2 (33 ± 4.7% and up to 30 gN m-2d-1, respectively). At the optimal hydraulic retention time, lower NH4+-N removal efficiencies and recovery rates were observed when real digestate was fed to MEC-1 (29 ± 6.6% and 60 ± 13 gNH4+-N m-2d-1, respectively) and MEC-2 (21 ± 7.9% and 10 ± 3.6 gNH4+-N m-2d-1, respectively), likely due to the higher complexity of the influent. The average energy requirements were 3.6-3.7 kWh kgNremoved-1, comparable with values previously reported in the literature and lower than conventional ammonia recovery processes. Results are promising and may reduce the need for costly and polluting processes for nitrogen synthesis.

Bioaugmentation-Assisted Phytostabilisation of Abandoned Mine Sites in South West Sardinia.

Bioaugmentation-assisted phytoremediation implies the administration of selected plant growth promoting bacteria, which significantly improve plant growth and sequestration of heavy metals. In this work, 184 bacterial strains associated with roots of Pistacia lentiscus were isolated from plants spontaneously growing in the abandoned Sardinian mining areas (SW Sardinia, Italy) and phylogenetically characterised. Twenty-one bacterial isolates were assayed for properties relevant for plant growth promotion and metal tolerance. Five different strains, belonging to the genera Novosphingobium, Variovorax, Streptomyces, Amycolatopsis, Pseudomonas, were selected based on their properties for the greenhouse phytoremediation tests. Among the tested inocula, the strain Variovorax sp. RA128A, able to produce ACC deaminase and siderophore, was able to significantly enhance germination and increase length and weight of shoots and roots. Irrespective of the applied treatment, mastic shrub was able to accumulate Cd, Pb and Zn especially in roots.

Start-up of a granular sludge sequencing batch reactor for the treatment of 2,4-dichlorophenol-contaminated wastewater.

In this study, a granular sludge sequencing batch reactor (GSBR) was started-up for the biological aerobic treatment of wastewater containing highly toxic 2,4-dichlorophenol (2,4-DCP), in presence of readily biodegradable sodium acetate (NaAc) as the growth substrate. Different influent concentrations of NaAc (420-800 mg/L) and 2,4-DCP (0-20 mg/L), as well as different operating conditions (i.e. cycle length), were tested in order to determine the optimal strategy for successful GSBR start-up: stable granulation and complete 2,4-DCP removal were achieved only when high NaAc influent concentration and volumetric organic loading rates (800 mg/L and 1.9 kgCOD/(m(3)·d), respectively), prolonged reaction phase (cycle time of 4 hours) and gradual increase of 2,4-DCP concentration in the influent were applied, thus providing useful information for process optimization in view of future scale-up. Granules were initially colonized by fungi which progressively disappeared during the start-up process, and complete 2,4-DCP removal was mostly due to bacterial activity, in particular Betaproteobacteria, as shown by fluorescence in situ hybridization (FISH).

Biological treatment of nitrogen-rich refinery wastewater by partial nitritation (SHARON) process.

Wastewater discharges containing high nitrogen levels can be toxic to aquatic life and cause eutrophication. In this study, the application of the SHARON (Single reactor for High activity Ammonium Removal Over Nitrite) process for the treatment of refinery wastewater (sour water) was evaluated, in view of its coupling with the ANAMMOX (ANaerobic AMMonium OXidation) process. A Continuous Flow Stirred Tank Reactor was initially fed with a synthetic medium, and the applied NH4-N concentration and wastewater/synthetic medium ratio were progressively increased up to 2000 mgN/L and 100%, respectively. Despite the high potential toxic effect of the real wastewater, overall SHARON performance did not decrease with the increasing real wastewater/synthetic medium ratio, and biomass showed progressive acclimation to the toxic compounds in the real wastewater, as demonstrated by toxicity assessments. NH4-N and dissolved organic carbon removal efficiency were around 50% and 65%, respectively. Moreover, the effluent was characterized by a NO2-N/NH4-N ratio of 0.9 +/- 0.01 and low nitrate concentration (<30 mgN/L), in line with the requirements for the subsequent treatment by the ANAMMOX process.

Effects of the cometabolite/growth substrate ratio on the aerobic degradation of 4-monochlorophenol.

Chlorinated phenolic compounds like 4-monochlorophenol (4CP) are characterized by high toxicity even at relatively low concentrations and by strong persistency in both water and soils. Since cometabolism was proved to enhance 4CP biological removal, a conventional Sequencing Batch Reactor (SBR) was used in this study for the cometabolic aerobic degradation of 4CP at different influent concentrations and volumetric organic loading rates (40-50 mg/L and 0.129-0.323 kgCOD-4CP/m3·d, respectively), with sodium acetate (NaAc) as the growth substrate. The effects of different 4CP/NaAc ratios on SBR performances were evaluated in terms of 4CP removal efficiencies and maximum specific removal rates in order to maximize reactor performances: a decrease in NaAc dosage as external growth substrate would lead to definitely lower operating costs. A positive correlation was observed between 4CP maximum specific removal rates and the applied 4CP/NaAc ratios, thus making further reduction in NaAc dosage possible.

Landfill gas generation after mechanical biological treatment of municipal solid waste. Estimation of gas generation rate constants.

Mechanical biological treatment (MBT) of residual municipal solid waste (RMSW) was investigated with respect to landfill gas generation. Mechanically treated RMSW was sampled at a full-scale plant and aerobically stabilized for 8 and 15 weeks. Anaerobic tests were performed on the aerobically treated waste (MBTW) in order to estimate the gas generation rate constants (k,y(-1)), the potential gas generation capacity (L(o), Nl/kg) and the amount of gasifiable organic carbon. Experimental results show how MBT allowed for a reduction of the non-methanogenic phase and of the landfill gas generation potential by, respectively, 67% and 83% (8 weeks treatment), 82% and 91% (15 weeks treatment), compared to the raw waste. The amount of gasified organic carbon after 8 weeks and 15 weeks of treatment was equal to 11.01+/-1.25kgC/t(MBTW) and 4.54+/-0.87kgC/t(MBTW), respectively, that is 81% and 93% less than the amount gasified from the raw waste. The values of gas generation rate constants obtained for MBTW anaerobic degradation (0.0347-0.0803y(-1)) resemble those usually reported for the slowly and moderately degradable fractions of raw MSW. Simulations performed using a prediction model support the hypothesis that due to the low production rate, gas production from MBTW landfills is well-suited to a passive management strategy.

Acetate-fed aerobic granular sludge for the degradation of chlorinated phenols.

In this study, the possibility to use acetate-fed aerobic granular sludge for the degradation of low chlorinated 4-mono-chlorophenol (4CP) and highly chlorinated 2,4,6-tri- chlorophenol (TCP) was investigated. A Granulated Sequencing Batch Reactor (GSBR) was used to carry out the experiments, with acetate as growth substrate. 4CP concentration in the influent ranged between 0 and 50 mg/l, while TCP concentration varied between 0 and 15 mg/l. Different operating conditions were applied in order to obtain the complete aerobic degradation of 4CP. For TCP degradation, anaerobic feeding and control of dissolved oxygen concentration in the bulk liquid were used to keep the granules core under anaerobic conditions due to diffusion limitations: the possibility to obtain TCP reductive dechlorination under aerated conditions was thus investigated. Differences in granules shape and size were observed with 4CP and TCP dosed in the influent, and the effects of such toxic compounds on acetate removal were evaluated.Aerobic granules grown on acetate as carbon source proved to be an interesting solution for the degradation of 4CP, showing good resistance to high 4CP concentrations in the influent even if unacclimated. The presence of TCP did not irreversibly inhibit biomass activity, and complete TCP degradation was achieved after acclimation.

[Cytological and bacteriological changes in women using the IUD]. / Alterazioni citologiche e batteriologiche nelle portatrici di DIU.

PIP: Vaginal cytological and bacteriological reports on 505 women with copper potentiated IUDs were examined and compared to those of a control group of 1050 women. No significant degree of difference in the incidence of dysplasia was observed though a modest increase in vaginal swelling, particularly that caused by monilia, was noted. (author's modified)^ieng

[Abscessing salpingo-oophoritis caused by Actinomyces in a woman using an IUD]. / Salpingo-ovarite ascessuale da Actinomices in donna portatrice di IUD.

PIP: Recent studies have demonstrated that there is a connection between actinomycetic genital swelling and longterm use of the Lippes Loop. After a literature review, a case of actinomycetic abscessing salpingo-ovaritis in a woman who had worn the same Lippes Loop for 12 years is reported. It is concluded that Actinomyces must be always considered a potential etiological agent in all cases where genital swelling is found in patients fitted with such loops. (author's modified)^ieng

Prolactin plasma levels and oral contraceptives at low dosage.

In the present study the Authors consider whether estroprogestins at low dosage may influence the basal levels of plasma Prolactin in a group of patients subdivided on the basis of their different ways of life. The results show that oral contraceptives containing 30 microgrammes of EE do not induce modifications on PRL levels; however these are significantly (p less than or equal to 0.01) lower in the smoker group. It has therefore been hypothesised that smoke may interfere with the regulatory mechanisms of PRL, even if the practical effects of such action in the ambit of the physiopathology of reproduction is not yet clear.

PIP: In this study, the authors considered whether estroprogestins at low dosage may influence the basal levels of plasma prolactin (PRL) in a group of patients subdivided on the basis of different lifestyle. Results showed that oral contraceptives containing 30 mcg ethinyl estradiol do not induce modifications of PRL levels; however, these are significantly lower (P or= 0.01) in the smoking group. It has therefore been hypothesized that smoke may interfere with the regulatory mechanisma of PRL, even if the practical effects of suck action on the physiopathology of reproduction are not yet clear.

Alpha-fetoprotein assay in patients treated with low-dose oral contraceptives.

AFP has proven to be a useful marker for liver neoplasms. The authors assayed AFP plasma levels in patients taking low-dose estro- progestinics . Patients were divided into three groups on the basis of their living habits. No difference was found in any group between AFP levels before and after treatment. However, in the group of smokers using oral contraceptives AFP levels were significantly higher.

PIP: Alpha-fetoprotein (AFP) plasma levels were assayed in women taking low dose combined preparations as AFP has proven to be a useful marker for benign or malignant liver neoplasms. 150 patients who sought advice on oral contraceptives (OCs) at the day centers of the Department of Obstetrics and Gynecology, University of Sassari (Italy) were examined. They ranged in age from 18-40 and all underwent the usual tests for detecting changes in the hepato-biliary function. Patients with previous liver pathologies were excluded on the basis of anamnesis and hematochemical tests. The study concentrated on 110 patients who were subdivided into 3 groups on the basis of some living habits. Group 1 included women only taking OCs; group 2 those who took OCs and smoked 10 or more cigarettes per day (OC+smoke); and group 3 included patients using OCs and taking alcoholic drinks as a habit (OC+alcohol). Serum AFP was assayed in all patients prior to treatment; the 2nd assay was carried out after a period of therapy with combined OCs lasting from 24-36 months. The data obtained were statistically analyzed according to the variance method. All changes in AFP levels in the 3 groups before and after combined OC treatment were compared and differences between the groups studied. There were no statistical differences between AFP levels before and after treatment in the 3 groups examined. In all cases, AFP levels were well below 25ng%ml. In the group of smokers who used OCs, AFP levels were significantly higher than in the higher 2 groups. These increased levels were always within normal limits and never reached 25ng%ml; AFP exceeding this value is considered as evidence of liver damage. The data show that the association of smoking and OCs can have unfavorable impications for the liver function.

Prognostic value of hCG, progesterone, 17-beta estradiol and the echoscopic examination in threatened abortion during the first trimester.

The Authors refer on the validity of echoscopic examination and hCG, progesterone and 17-beta estradiol values in the prognosis of threatened abortion during the first trimester of pregnancy in 62 patients. The echoscopic examination allowed a prognosis to be made in accordance with the clinical evolution of threatened abortion in 90% of the cases; the plasma levels of hCG and progesterone in 87% of the cases; 17-beta estradiol in 83% of the cases. The Authors conclude that the simultaneous assay of hCG, progesterone and 17-beta estradiol plasma levels does not improve the prognostic validity of echoscopy but, in some cases, can provide essential details on the etiology of threatened abortion itself.

Incidence and duration of breast-feeding in a group of primiparae after physiological delivery.

A study has been performed on the incidence and duration of breast feeding in a group of 103 primiparous women who delivered in the Obstetrics Department of Sassari in 1980. The most important maternal variables that could be related with breast feeding were maternal age, level of school education, maternal feelings concerning the present pregnancy and maternal information concerning the advantages of breast feeding.

A population of fast radio bursts at cosmological distances.

Searches for transient astrophysical sources often reveal unexpected classes of objects that are useful physical laboratories. In a recent survey for pulsars and fast transients, we have uncovered four millisecond-duration radio transients all more than 40° from the Galactic plane. The bursts' properties indicate that they are of celestial rather than terrestrial origin. Host galaxy and intergalactic medium models suggest that they have cosmological redshifts of 0.5 to 1 and distances of up to 3 gigaparsecs. No temporally coincident x- or gamma-ray signature was identified in association with the bursts. Characterization of the source population and identification of host galaxies offers an opportunity to determine the baryonic content of the universe.

Transformation of a star into a planet in a millisecond pulsar binary.

Millisecond pulsars are thought to be neutron stars that have been spun-up by accretion of matter from a binary companion. Although most are in binary systems, some 30% are solitary, and their origin is therefore mysterious. PSR J1719-1438, a 5.7-millisecond pulsar, was detected in a recent survey with the Parkes 64-meter radio telescope. We show that this pulsar is in a binary system with an orbital period of 2.2 hours. The mass of its companion is near that of Jupiter, but its minimum density of 23 grams per cubic centimeter suggests that it may be an ultralow-mass carbon white dwarf. This system may thus have once been an ultracompact low-mass x-ray binary, where the companion narrowly avoided complete destruction.