We verified the usefulness of water quality indices (WQI) to assess the water quality from multiple measured parameters, and to evaluate spatial and temporal changes. Measured parameters include many ...of those recommended by the GEMS/Water UNEP program. Two WQI (subjective and objective - WQI sub(sub) and WQI sub(obj)) take into consideration 20 parameters. Another index (minimal - WQI sub(min)) was developed considering only three parameters: turbidity, dissolved oxygen, and either conductivity or dissolved solids. WQI sub(sub) tends to overestimate the pollution due to the use of a subjective constant, which is not necessarily correlated with the measured parameters. WQI sub(min) shows a similar trend to WQI sub(sub) and WQI sub(obj) at a lower analytical cost; however, it should be combined with WQI sub(obj) to corroborate the results. The use of WQI could be of particular interest for developing countries, because they provide cost-effective water quality assessment as well as the possibility of evaluating trends. As a case study, we report on the use of WQI to evaluate spatial and seasonal changes in the water quality from the Suquia River in Cordoba City (Argentina) and nearby locations. The city urban activity produces a serious and negative effect on the water quality; this is particularly severe in locations following the city sewage discharge. The dry season shows the worst water quality.
•Ducted Fuel Injection (DFI) enables for highly mixing controlled diesel combustion.•DFI enhances air entrainment in the near-nozzle region and turbulence at duct exit.•Remarkable droplet count ...reduction due to enhanced evaporation for DFI.•Impressive soot reduction potential due to narrower equivalence ratio distribution.
Enhancing mixture preparation upstream of the premixed autoignition zone is a solution to reduce soot emission formation in compression ignition engines. With this aim, in recent years, Ducted Fuel Injection (DFI) concept has been developed: DFI is based on the idea of injecting the fuel spray through a small cylindrical pipe within the combustion chamber at a certain distance from the nozzle injector hole. Recent research studies have highlighted the high potential of this innovative concept for soot mitigation in both constant volume vessel and engine-like operating conditions. However, the mechanisms driving the soot reduction have not yet been fully understood. The aim of this research work is to further investigate the DFI concept, evaluating its impact on the spray characteristics, on the air/fuel mixing and, therefore, on the soot formation phenomena. Firstly, an experimental activity was carried out by means of a constant volume vessel test bench with optical accesses to compare the spray evolution and sizing with and without duct adoption, over a wide range of vessel thermodynamic conditions and injection pressures. After that, a simulation setup was defined in the commercially available 3D-CFD software CONVERGE reproducing the experimental test bench, calibrating and validating the spray model. Firstly, the spray model was calibrated and validated considering the same non-reacting conditions exploited in the experimental analysis. Then, the calibrated spray model was used as a virtual tool to investigate the air entrainment process. As a results, the DFI adoption increases the air entrainment in the near-nozzle region caused by the high velocity spray that generates a pumping effect at the duct inlet. Moreover, mixing process is also enhanced by the turbulence distribution at the duct exit resulting in a narrower distribution of equivalence ratio at the ignition. As a consequence of the more effective air entrainment and improved turbulent mixing, DFI remarkably mitigates soot emissions, with a reduction up to 80% with respect to free spray configuration in all tested operating conditions.
Background
IgA nephropathy (IgAN) is a common complex disease with a strong genetic involvement. We aimed to identify novel, rare, highly penetrant risk variants combining family‐based linkage ...analysis with whole‐exome sequencing (WES).
Methods
Linkage analysis of 16 kindreds of South Italian ancestry was performed using an ‘affected‐only’ strategy. Eight most informative trios composed of two familial cases and an intrafamilial control were selected for WES. High‐priority variants in linked regions were identified and validated using Sanger sequencing. Custom TaqMan assays were designed and carried out in the 16 kindreds and an independent cohort of 240 IgAN patients and 113 control subjects.
Results
We found suggestive linkage signals in 12 loci. After sequential filtering and validation of WES data, we identified 24 private or extremely rare (MAF <0.0003) linked variants segregating with IgAN status. These were present within coding or regulatory regions of 23 genes that merged into a common functional network. The genes were interconnected by AKT, CTNNB1, NFKB, MYC and UBC, key modulators of WNT/β‐catenin and PI3K/Akt pathways, which are implicated in IgAN pathogenesis. Overlaying publicly available expression data, genes/proteins with expression notably altered in IgAN were included in this immune‐related network. In particular, the network included the glucocorticoid receptor gene, NR3C1, which is the target of corticosteroid therapy routinely used in the treatment of IgAN.
Conclusion
Our findings suggest that disease susceptibility could be influenced by multiple rare variants acting in a common network that could provide the starting point for the identification of potential drug targets for personalized therapy.
Summary
The effectiveness of a 12‐week course of sofosbuvir‐ledipasvir in treatment‐experienced HCV genotype 1b‐infected patients with cirrhosis is still under debate. Our primary endpoint was to ...compare the sustained virological response at post‐treatment week 12 (SVR12) of sofosbuvir‐ledipasvir in combination with ribavirin for 12 weeks, and sofosbuvir‐ledipasvir alone for 24 weeks. This was a prospective observational study that enrolled 424 (195 naive, 229 experienced; 164 treated for 12 weeks with Ribavirin and 260 with sofosbuvir‐ledipasvir alone for 24 weeks) consecutive HCV genotype 1b‐infected patients with cirrhosis. The SVR12 rates were 93.9% and 99.2% in patients treated for 12 and 24 weeks, respectively (P = .002). The baseline characteristics of patients treated for 12 weeks were significantly different from those treated for 24 weeks as regards their younger age (P = .002), prevalence of Child‐Pugh class A (P = .002), lower MELD scores (P = .001) and smaller number of nonresponders (P = .04). The shorter treatment was significantly associated with a lower SVR12 in univariate and multivariate analyses (P = .007 and P = .008, respectively). The SVR rate was unaffected by age, gender, BMI, Child‐Pugh class, MELD score or previous antiviral treatment. Patients receiving ribavirin experienced more episodes of ascites and headache but less recurrence of hepatocellular carcinoma (HCC), and were prescribed more diuretics and cardiopulmonary drugs. No patient discontinued treatment. The therapeutic regimen of sofosbuvir‐ledipasvir plus ribavirin administered for 12 weeks was less effective than sofosbuvir‐ledipasvir alone given for 24 weeks. At odds with European guidelines, the recommended 12‐week treatment with sofosbuvir‐ledipasvir alone might be suboptimal for this setting of patients.
The aerobic biodegradation of lindane (
γ-hexachlorocyclohexane) by a consortium of acclimated bacteria from sediment at a polluted site on the Suquia River, Cordoba, Argentina, is reported. The ...bacteria were acclimated for 30 days under aerobic conditions, using a minimal culture medium containing lindane
(0.034
mM)
as sole carbon source. Growth of the bacterial consortium decreased at a lindane concentration of
1.03
mM
and was totally inhibited at
2.41
mM
. The consortium showed initial lindane degradation rates of 4.92×10
−3, 11.0×10
−3 and
34.8×10
−3
mM
h
−1
when exposed to lindane concentrations of 0.069, 0.137 and
0.412
mM
, respectively. Chloride concentration increased during aerobic biodegradation, indicating lindane mineralization. A metabolite identified as
γ-2,3,4,5,6-pentachlorocyclohexene appeared during the first
24
h
of biodegradation. Four different bacteria, identified as
Sphingobacterium spiritivorum,
Ochrobactrum anthropi,
Bosea thiooxidans and
Sphingomonas paucimobilis, were isolated. Pure strains of
B. thiooxidans and
S. paucimobilis degraded lindane after 3 days of aerobic incubation. This is the first report of lindane biodegradation by
B. thiooxidans.
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