Coke Wastewater Treatment by a Three-Step Activated Sludge System

The treatment of industrial coke wastewater was studied in a laboratory-scale activated sludge system. The concentrations of the main pollutants in the wastewater ranged between 800 and 1870 mg COD/l, 100–221 mg phenols/l, 198–427 mg SCN/l, 133–348 mg ${\text{NH}}_4^ + - {{\text{N}} \mathord{\left/ {\vphantom {{\text{N}} {\text{l}}}} \right. \kern-0em} {\text{l}}}$ and 11–41 mg CN^?/l. To avoid inhibition phenomena resulting from the high concentrations of thiocyanate, ammonium nitrogen and cyanide a three-step process was implemented. The first step was anoxic for the removal of nitrates, followed by an oxic step during which biodegradation of phenols and thiocyanates took place, and by a second oxic step to oxidize ammonium nitrogen to nitrate. The dilution effect due to the recirculation of the final effluent to the head of the process and also, the separation of the nitrification step from the biodegradation of thiocyanate led to much higher efficiencies than when the process was carried out simultaneously. Very high removals were obtained (99% phenols, 97% SCN^?, 63% COD, 98% ${\text{NH}}_4^ + - {\text{N}}$ , 90% total-N and 99% cyanide) employing hydraulic residence times of 15.4 h for denitrification, 98 h for phenol and thiocyanate biodegradation and 86 h for nitrification.     

Short-term spatiotemporal variation of soil CO2 emission,temperature, moisture and aeration in sugarcane field reform areas under the influence of precipitation events

Soil CO₂ emission (FCO₂) in agricultural areas results from the interaction of different factors such as climate and soil conditions. Our objective was to investigate the spatiotemporal variation of FCO₂, temperature (T_soil), moisture (M_soil) and air-filled pore space (AFPS), as well as their interactions, during the sugarcane field reform. The study was conducted on a 90 × 90 m sampling grid with 100 points at 10 m spacings. Ten assessments of FCO₂, T_soil and M_soil were carried out at each point over a 28-day period. The greatest mean values of FCO₂ (0.74 g m⁻² hr⁻¹) and M_soil (31.7%) were obtained on Julian day 276, 2013, being associated with precipitation events at the study site. Also, the smallest values of AFPS (19.17%) and T_soil (20.90°C) were observed on the same day. The spatial variability of FCO₂, T_soil, M_soil and AFPS was best described by an adjusted spherical model, although an exponential model better fitted some results. The spatial pattern of all soil attributes showed little temporal persistency, indicating a high complexity for FCO₂ during precipitation. Correlation maps assisted in identifying regions where M_soil and AFPS better controlled the emission process and where T_soil was important. A major challenge for world agriculture is to increase the efficiency of conventional soil management practices. We highlight the importance of the spatial pattern of soil properties that directly influence the CO₂ emission dynamics. Future mitigation actions should involve less intense tillage and ensure homogeneous applications of soil inputs, thereby reducing production costs and the contribution of these activities to CO₂ emissions during the sugarcane field reform.     

Nitric oxide impacts bovine sperm capacitation in a cGMP‐dependent and cGMP‐independent manner

We aimed to elucidate whether NO acts in in vitro sperm capacitation in bovine via cGMP/PKG1 pathway. For this, cryopreserved bovine sperm were capacitated in vitro with 20 µg/ml heparin (Control) plus treatments: 1 mM L‐arginine (L‐arg, NO precursor), 50 µM Rp‐8‐Bromo‐β‐phenyl‐1,N²‐ethenoguanosine‐3′,5′‐cyclic monophosphorothioate (Rp‐8‐Br‐cGMPS, selective inhibitor of the binding site for cGMP in PKG1), 1 mM 2‐Phenyl‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl 3‐oxide (PTIO, NO scavenger), and the combinations of L‐arg + RP‐8‐Br‐cGMPS and L‐arg + PTIO. Sperm motility and vigour were determined by phase‐contrast microscopy, capacitation status by chlortetracycline staining, and the intracellular concentration of cGMP was measured by ELISA. Data were subjected to analysis of variance and means compared with SNK test at 5% probability. Motility and vigour were lower in sperm treated with PTIO when compared to Control and other treatments (p < .05). The L‐arg treatment showed the highest percentage of capacitated sperm when compared to the Control and other treatments (Rp‐8‐Br‐cGMPS, L‐arg + Rp‐8‐Br‐cGMPS and PTIO) (69.8 ± 3.4%, 51.2 ± 3.0, 51.1 ± 2.1, 51.2 ± 3.0 and 45.5 ± 2.7, respectively) (p < .05). The capacitation ratio (%) was lower in treatments with Rp‐8‐Br‐cGMPS, L‐arg + Rp‐8‐Br‐cGMPS and PTIO, respectively (p < .05). Lastly, cGMP concentration (pmol/ml) was lower in PTIO and L‐arg + PTIO (1.3 ± 0.3 and 1.6 ± 0.4) and was higher in Rp‐8‐Br‐cGMPS and L‐arg + Rp‐8‐Br‐cGMPS (3.7 ± 0.4 and 4.0 ± 0.5) treatments. We showed that during in vitro capacitation of cattle: (a) NO influences sperm motility and vigour; (b) NO is associated with cGMP synthesis through two independent pathways and (c) the cGMP/PKG1 pathway has a partial role in sperm capacitation and does not involve the L‐arg/NO.     

Chemical Characterization and Release of Polyphenols from Pecan Nut Shell [<Emphasis Type="Italic">Carya illinoinensis</Emphasis> (Wangenh) C. Koch] in Zein Microparticles for Bioactive Applications

The pecan nut [Carya illinoinensis (Wangenh) C. Koch] is a natural source of polyphenols with antioxidant properties. In this study, the encapsulation of aqueous and hydroalcoholic extracts of pecan nut shell were evaluated for the release of bioactive compounds and antioxidant potential in order to explore food applications using zein as encapsulating agent. The extracts showed high contents of total phenolics, condensed tannins and high antioxidant activity. Concentrations of proanthocyanidins were 9-fold higher in hydroalcoholic extracts. The LC-DAD analysis showed that catechins were the major phenolic compounds in samples, with epigallocatechin levels up to 138.62 mg mL^?1. Zein microparticles loaded with aqueous extract released 2.3 times more phenolic compounds than the hydroalcoholic extracts and the DSC thermograms showed that extracts of pecan nut shell remained thermally stable up to 240 °C. The zein microcapsules obtained in this study were efficiently encapsulated and represent an interesting additive due its high antioxidant capacity, physicochemical characteristics and morphology. The use of zein microparticles combined with natural extracts constitute a step forward in the improvement of current technology for delivering phenolic compounds with applications in functional foods and nutraceuticals.     

The effects of osmolality on sperm quality in <Emphasis Type="Italic">Jenynsia multidentata</Emphasis> (Cyprinodontiformes: Anablepidae)

Sperm quality tests on fish are classically used for evaluating cryopreservation procedures, and they are also promising to assess aquatic toxicity and biomarkers of xenobiotic effects on reproduction. Osmotic shock from the storage medium is one of the main factors affecting sperm quality during evaluation. Thus, the objective of this study was to evaluate the effects of different osmolalities (240–460 mOsm/kg) for at least 4 days on the sperm quality parameters of the viviparous fish Jenynsia multidentata. The level of significance was (P < 0.05). The plasma osmolality of J. multidentata is 326 ± 3.9 mOsm/kg. The motility of fresh semen was higher in osmolalities of 280 and 300 mOsm/kg but did not differ between osmolalities from 240 to 320 mOsm/kg. Above 380 mOsm/kg, the motility observed was 0 %. Over the time period studied motility increased with increasing osmolality, and the most constant and long-lasting rates were between 300 and 320 mOsm/kg. On the 4th day of evaluation, higher membrane integrity rates were observed between 280 and 360 mOsm/kg, higher mitochondrial membrane potential was observed between 300 and 460 mOsm/kg, and higher DNA integrity rates were observed between 260 and 380 mOsm/kg. Moreover, osmolalities ≥460 and ≤240 resulted in the lowest motility and DNA integrity levels. Over 4 days, the plasma membrane integrity was significantly lower at ≤260 and ≥400 mOsm/kg, and the mitochondrial membrane potential was significantly lower only in osmolalities ≤240 mOsm/kg. Therefore, we conclude that for sperm quality preservation in J. multidentata, an osmolality of 300–320 mOsm/kg of the most suitable diluent is necessary. Furthermore, we conclude that the storage of sperm in a hyposmotic (<260 mOsm/kg) or hyperosmotic (>400 mOsm/kg) solution affects not only motility but also other sperm quality parameters.     

Molecular characterization of Diplodia seriata,a new pathogen of Prunus laurocerasus in Italy

Twig cankers and diebacks were observed on cherry laurel (Prunus laurocerasus L.) hedges located in a private garden of Perugia (Central Italy). Four fungal isolates, forming gray colonies and aerial mycelium, were obtained from cankers. For each isolate, Koch’s postulates were fulfilled by inoculating cherry laurel plants. Based on cultural characteristics, rep-PCR and phylogenetic analyses on ITS and EF1-α nucleotides sequences, the isolates were identified as Diplodia seriata De Not. To the best of our knowledge, this is the first report of D. seriata as a new pathogen of P. laurocerasus. The severe symptoms and the wide distribution of the host plant make the pathogen potentially dangerous for this ornamental species.     

Wildlife translocation: the conservation implications of pathogen exposure and genetic heterozygosity

Background  

A key challenge for conservation biologists is to determine the most appropriate demographic and genetic management strategies for wildlife populations threatened by disease. We explored this topic by examining whether genetic background and previous pathogen exposure influenced survival of translocated animals when captive-bred and free-ranging bighorn sheep (Ovis canadensis) were used to re-establish a population that had been extirpated in the San Andres Mountains in New Mexico, USA.     

Development and characterization of carbon-honeycomb monoliths from kenaf natural fibers: A preliminary study

A series of carbon-honeycomb monoliths from kenaf natural fibers (KNF) have been prepared and characterized. Firstly, KNF were physically mixed with polyvinyl acetate (PVA) as a binder and next the mixture was extruded through a die to form disc type monoliths. After the extrusion, the monoliths were dried, carbonized and, finally, physically activated with synthetic air at different temperatures (350-550 °C). The carbon-honeycomb monoliths were characterized by N₂ adsorption at −196 °C, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). The experimental results indicate that the method proposed in this work was suitable for the synthesis of solid carbon monoliths with the presence of large meso- and macropores like long parallel and straight canals extended through their structure. MIP data and SEM images illustrate an evident and progressive aperture of the blocked parallel channels with an increase of the activation temperature.     

Mesohabitat associations of the threatened San Marcos salamander (Eurycea nana) across its geographic range

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Exotic and invasive species compromise the seed bank and seed rain dynamics in forests undergoing restoration at urban regions

The control of exotic and invasive species in areas undergoing recovery is a challenge for ecological restoration and this problem may be even greater in urbanized areas. This study evaluated the seed bank and seed rain of a 5-year-old riparian forest located at the metropolitan region of Belo Horizonte in southeast Brazil, and verified changes over time in the abundance and species richness and whether planted species already were providing propagules to the site. At the forest, fifteen parcels of 100 m² were distributed randomly and soil samples were collected thrice (October 2011, March 2012 and July 2012) to evaluate the seed bank. Seed traps were installed in nine parcels to collect propagules over 1 year. Propagules were segregated and germinate at greenhouse. Species richness and abundance were estimated, and variance and similarity were quantified. In total, 86 species were recorded in the seed banks, 41.9% natives and 33.7% exotics, with the predominance of herbs (87.2%) and only 7% of trees. Species classified as weeds amounted to 52.3%. In the seed rain 642 seedlings germinated but they belonged to only 10 species, half of them were exotics. Regarding life forms, half of the species were arboreal and dominated the samples, highlighting the exotic species Melia azedarach. The species richness of the seed bank did not differ by season, unlike the seed rain which varied significantly by month. Seed bank and seed rain species had a very low floristic similarity with the list of planted species, suggesting that few planted trees had dispersed or were stocking propagules. Many non-planted species were recorded, mostly exotics and/or invasive that were probably derived from the surrounding urban matrix. These might interrupt the successional dynamics of the restoration forest and compromise the restoration process in the medium and long-terms. Our results highlight: (1) the importance of monitoring areas undergoing restoration; (2) that restoration methods and management actions directed to control exotic and invasive species are particularly important for sites in urban regions; and (3) the relevance of conserving forest fragments as sources of propagules for nearby areas.