Estructura hidrográfica de la Bahía de Bluefields, Nicaragua

In March and October of 2000, under the DIPAL II project (Proyecto para el Desarrollo Integral de la Pesca Artesanal en la Región Autónoma del Atlántico Sur), two hydrographic surveys were carried out in the Bay of Bluefields to study their hydrography during the dry and rainy seasons. Water temperature, salinity and turbidity were determined both at the surface and the bottom of the bay. The results obtained are consistent with previous studies carried out in this area. In March, water temperature and salinity were lower and higher, respectively, than in October. Water turbidity increased with increased fresh water input as a result of a greater movement of suspended sediments and organic matter into the water body. Saline wedges were observed in deep strata during the two months of sampling in the adjacent areas to the bars of The Bluff and Hone Sound. In the first case the wedge extended to the northwest up to the area of Bluefields, while in the second case it extended to the west reaching the western coast of the bay. The vertical gradient of salinity was stronger in October, when the superficial flow of fresh water in the whole bay was more intense. A circulation pattern related to the salinity field was recognised: fresh water introduced by the Caño Negro and Escondido rivers moves along the western coast of the bay, while sea water enters the bay towards the northwest, throughout the whole water column, at the bars of The Bluff and Hone Sound. Fresh water introduced by the River Torsuani moves along the eastern coast towards the open sea at the southern end of the bay

Prospects for reduction of the impact of wastewater discharge from urban areas on surface water quality in view of legal regulations

Despite full adoption of EU requirements into current legal regulations in Poland, surface waters as sewage receivers in urban areas still cannot be considered fully protected, especially against contamination from sewer overflows and storm water systems. The examples discussed demonstrate that urban wastewater discharged from sewer overflows and storm water systems during rainfalls has a clearly dominant share in the load of pollutants emitted to the receiver. It is therefore important to develop efficient tools of water protection against these contaminants. Uniform but rather limited provisions applicable throughout the country do not take account of specific local conditions, especially size of wastewater receivers and size and characteristics of the catchment area, preventing therefore effective and economically viable water protection. The results of this research, carried out in Lodz, examining pollution loads discharged from the urban catchment area, illustrate that current approach to surface water protection issues requires a revision. Feasibility of regulatory changes in the area of setting requirements for effective receiver protection against pollutants discharged from urban areas was presented, considering the impact of untreated wastewater on the receiving water. It is also necessary to take comprehensive measures both in terms of research on pollutant emissions and their impact on the receiver and the method to utilize the results of such studies. This would enable more widespread use of urban wastewater discharge system modeling, which in turn would enable a reliable assessment of their impact on the receiver and taking appropriate modernization decisions. All of these activities are preconditions for sustainable rainwater management in urban areas

The ng_ζ1 toxin of the gonococcal epsilon/zeta toxin/antitoxin system drains precursors for cell wall synthesis

Bacterial toxin–antitoxin complexes are emerging as key players modulating bacterial physiology as activation of toxins induces stasis or programmed cell death by interference with vital cellular processes. Zeta toxins, which are prevalent in many bacterial genomes, were shown to interfere with cell wall formation by perturbing peptidoglycan synthesis in Gram-positive bacteria. Here, we characterize the epsilon/zeta toxin–antitoxin (TA) homologue from the Gram-negative pathogen Neisseria gonorrhoeae termed ng_ɛ1 / ng_ζ1. Contrary to previously studied streptococcal epsilon/zeta TA systems, ng_ɛ1 has an epsilon-unrelated fold and ng_ζ1 displays broader substrate specificity and phosphorylates multiple UDP-activated sugars that are precursors of peptidoglycan and lipopolysaccharide synthesis. Moreover, the phosphorylation site is different from the streptococcal zeta toxins, resulting in a different interference with cell wall synthesis. This difference most likely reflects adaptation to the individual cell wall composition of Gram-negative and Gram-positive organisms but also the distinct involvement of cell wall components in virulence

Toward Zero Variance in Proteomics Sample Preparation:Positive-Pressure FASP in 96-Well Format (PF96) Enables Highly Reproducible, Time- and Cost-Efficient Analysis of Sample Cohorts

As novel liquid chromatography-mass spectrometry (LC-MS) technologies for proteomics offer a substantial increase in LC-MS runs per day, robust and reproducible sample preparation emerges as a new bottleneck for throughput. We introduce a novel strategy for positive-pressure 96-well filter-aided sample preparation (PF96) on a commercial positive-pressure solid-phase extraction device. PF96 allows for a five-fold increase in throughput in conjunction with extraordinary reproducibility with Pearson product-moment correlations on the protein level of r = 0.9993, as demonstrated for mouse heart tissue lysate in 40 technical replicates. The targeted quantification of 16 peptides in the presence of stable-isotope-labeled reference peptides confirms that PF96 variance is barely assessable against technical variation from nanoLC-MS instrumentation. We further demonstrate that protein loads of 36-60 μg result in optimal peptide recovery, but lower amounts ≥3 μg can also be processed reproducibly. In summary, the reproducibility, simplicity, and economy of time provide PF96 a promising future in biomedical and clinical research