Ion chromatography–electrospray mass spectrometry for the identification of low-molecular-weight organic acids during the 2,4-dichlorophenol degradation

End-product identification of organic pollutants during oxidation water treatments is of environmental concern due to their potential toxicity. In this work the coupling of ion chromatography (IC), equipped with a membrane ion suppressor, and electrospray ionization mass spectrometry (ESI-MS) has been successfully exploited for the identification of novel low molecular weight organic acids formed as final by-products of 2,4-dichloro-phenol (DCP) degradation by Fenton's reagent, an oxidation method widely employed to degrade recalcitrant organic pollutants in industrial wastewater. The IC-ESI-MS analytical set-up not only allowed the detection of known organic acids but also the identification of 13 new low molecular weight organic acids as a result of extensive oxidation of the parent organic pollutant. Some of the novel organic acids were shown to be chlorine containing by-products and, consequently, of environmental concern. The analytical set-up could be used for characterizing the unknown organic carbon fraction arising from oxidation water treatments.

Hydraulic shear stress calculation in a sequencing Batch biofilm reactor with granular biomass

This paper reports the results of an experimental study specifically aimed at developing a simple methodology for calculating hydrodynamic shear forces in a sequencing batch biofilm reactor (SBBR) system with granular biomass. Using such a methodology, the hydrodynamic shear forces are simply calculated by measuring bed porosity and pressure losses. In addition, by applying this methodology an explanation for the biomass evolution from biofilm to granules under aerobic conditions has been provided and the following mechanism has been proposed: (i) formation of a thin biofilm that fully covers the carrier; (ii) increase of biofilm thickness; (iii) break-up of the attached biofilm with release of biofilm particles; (iv) rearrangement of biofilm particles in smooth granules. The hydrodynamic shear forces trend during the start-up period provides an explanatory key for the generation process of granular biomass. In fact, during the first two steps, the SBBR is characterized by rather weak shear forces values (lower than 1 dyn/cm2). Under these weak shear forces, the biofilm grows by increasing its thickness through a porous structure and weak adhesion strengths. Such a continuous increase of biofilm thickness produces an increase of the shear forces with negative effect on biomass stability, causing the detachment of biofilm particles. In turn, such detachment causes a further sharp increase of shear forces (more than 10 times) that promotes the rearrangement of the detached biofilm particles in smooth granules. A correlation between biomass density and hydrodynamic shear forces was observed. In particular, the biomass density linearly increases with the increase of shear stress.

Photon transitions in Upsilon(2S) and Upsilon(3S) decays

We have studied the inclusive photon spectra in Upsilon(2S) and Upsilon(3S) decays using a large statistics data sample obtained with the CLEO III detector. We present the most precise measurements of electric dipole (E1) photon transition rates and photon energies for Upsilon(2S) --> gammachi(bJ)(1P) and Upsilon(3S) --> gammachi(bJ)(2P) (J = 0, 1, 2). We measure the rate for a rare E1 transition Upsilon(3S) --> gammachi(b0)(1P) for the first time. We also set upper limits on the rates for the hindered magnetic dipole (M1) transitions to the eta(b)(1S) and eta(b)(2S) states.

Search for X(3872) in gammagamma fusion and radiative production at CLEO

We report on a search for the recently reported X(3872) state using 15.1 fb(-1) of e(+)e(-) data taken in the sqrt[s] = 9.46-11.30 GeV region. Separate searches for the production of the X(3872) in untagged gammagamma fusion and e(+)e(-) annihilation following initial state radiation are made by taking advantage of the unique angular correlation between the leptons from the decay J/psi --> l(+)l(-) in X(3872) decay to pi(+)pi(-)J/psi. No signals are observed in either case, and 90% confidence upper limits are established as (2J+1)Gamma(gammagamma)(X(3872))B(X --> pi(+)pi(-)J/psi) < 12.9 eV and Gamma(ee)(X(3872))B(X- -> pi(+)pi(-)J/psi) < 8.3 eV.

Study of the semileptonic charm decays D(0)-->pi(-)l(+)nu and D(0)-->K(-)l(+)nu

We investigate the decays D(0)-->pi(-)l(+)nu and D(0)-->K(-)l(+)nu, where l is e or mu, using approximately 7 fb(-1) of data collected with the CLEO III detector. We find R(0) identical with B(D(0)-->pi(-)e(+)nu)/B(D(0)-->K(-)e(+)nu)=0.082+/-0.006+/-0.005. Fits to the kinematic distributions of the data provide parameters describing the form factor of each mode. Combining the form factor results and R(0) gives |f(pi)(+)(0)|(2)|V(cd)|(2)/|f(K)(+)(0)|(2)|V(cs)|(2)=0.038(+0.006+0.005)(-0.007-0.003).

Measurement of the muonic branching fractions of the narrow upsilon resonances

The decay branching fractions of the three narrow Upsilon resonances to mu(+)mu(-) have been measured by analyzing about 4.3 fb(-1) e(+)e(-) data collected with the CLEO III detector. The branching fraction B(Upsilon(1S)-->mu(+)mu(-))=(2.49+/-0.02+/-0.07)% is consistent with the current world average, but B(Upsilon(2S)-->mu(+)mu(-))=(2.03+/-0.03+/-0.08)% and B(Upsilon(3S)-->mu(+)mu(-))=(2.39+/-0.07+/-0.10)% are significantly larger than prior results. These new muonic branching fractions imply a narrower total decay width for the Upsilon(2S) and Upsilon(3S) resonances and lower other branching fractions that rely on these decays in their determination.

Observation of 1(-)0(-) final states from psi(2S) decays and e(+)e(-) annihilation

Using CLEO data collected from CESR e(+)e(-) collisions at the psi(2S) resonance and nearby continuum at sqrt[s]=3.67 GeV, we report the first significantly nonzero measurements of light vector-pseudoscalar hadron pair production (including rhopi, omegapi, rhoeta, and K(*0)K0 ) and the pi(+)pi(-)pi(0) final state, both from psi(2S) decays and direct e(+)e(-) annihilation.

Search for the lepton-flavor-violating leptonic B(0)-->mu(+/-)tau(-/+) and B(0)-->e(+/-)tau(-/+)

We have searched a sample of 9.6 x 10(6) BB events for the lepton-flavor-violating leptonic B decays, B(0)-->mu(+/-)tau(-/+) and B(0)-->e(+/-)tau(-/+). The tau lepton was detected through the decay modes tau-->lnunu(-) , where l=e, mu. There is no indication of a signal, and we obtain the 90% confidence level upper limits B(B(0)-->mu(+/-)tau(-/+))<3.8 x 10(-5) and B(B(0)-->e(+/-)tau(-/+))<1.3 x 10(-4).

First observation and Dalitz analysis of the D0-->K(0)Setapi(0) decay

Using 9.0 fb(-1) of integrated luminosity in e(+)e(-) collisions near the Upsilon(4S) mass collected with the CLEO II.V detector we report the first observation of the decay D0-->K(0)(S)etapi(0). We measure the ratio of branching fractions, BR(D0-->K(0)(S)etapi(0))BR / (D0-->K(0)(S)pi(0))=0.46+/-0.07+/-0.06. We perform a Dalitz analysis of 155 selected D0-->K(0)(S)etapi(0) candidates and find leading contributions from a(0)(980)K(0)(S) and K(*)(892)eta intermediate states.

Tertiary filtered municipal wastewater as alternative water source in agriculture: a field investigation in Southern Italy

Results are reported concerning a 2-year field investigation on municipal wastewater reclamation for the irrigation of two experimental crops: tomato and fennel. Throughout the investigation, approximately 500 m(3) of tertiary membrane filtered wastewater without further disinfection was supplied to one of two parcels (500 m(2) each) of a test field located in Southern Italy. The second parcel was comparatively irrigated with 500 m(3) of conventional well water. Objectives of the investigation were (i) the evaluation of the performance of a membrane filtration pilot plant (productivity=0.7 m(3)h(-1)) for tertiary treatment and (ii) the comparison between agronomic results (features of soil and crops) after irrigation with reclaimed wastewater versus conventional groundwater. Over long term operation, the pilot plant performance resulted very good in terms of suspended solids and bacterial removal. Referring to the agronomic results, no substantial differences were observed after 2 years, both in terms of microbiological quality of the crops and characteristics of the soil. The whole results indicate membrane filtered municipal effluent as a viable alternative water resource for irrigation.

Chronic hemodialysis in a Nigerian teaching hospital: practice and costs

The incidence of end-stage renal disease (ESRD) is on the rise in developing countries. To identify issues related to renal replacement therapy in ESRD patients in the developing world, we analyzed the practice and costs of hemodialysis in Nigerian ESRD patients. Ten ESRD patients were dialyzed at the Jos University Teaching Hospital, Jos, Plateau State, Nigeria, between June 15 and July 15, 2003. In these patients, we analyzed initiation, vascular access issues, frequency, duration, adequacy and economics of chronic hemodialysis. The Nigerian patients were referred to the nephrologist for the first time only when they had developed frank uremia. No patient had a permanent vascular access at the time dialysis was initiated. Only two patients had a functioning dialysis fistula, while the other eight patients were dialyzed through temporary femoral vein catheters that were removed after each dialysis. Frequency of dialysis was three times weekly in 2 patients, twice weekly in 1 patient and once weekly or less frequently in 7 patients. The duration of a dialysis session was prescribed to be 4 hours, but sessions often lasted for as long as 10 hours because of breakdowns of the antiquated dialysis machines. The urea reduction ratio was 45.3 +/- 8.6%. In every case, the cost of dialysis was borne by the patients and their families. Comparison of the cost of dialysis, with extensive re-use of supplies, to monthly incomes of Nigerians with different professions revealed that the great majority of Nigerians cannot afford three times weekly dialysis. Underdialysis in Nigerian ESRD patients is common and caused by socioeconomic factors and technologic deficits. One step towards correction of underdialysis could be sharing of the cost of dialysis by the public.

Oxidation pathways for ozonation of azo dyes in a semi-batch reactor: a kinetic parameters approach

In this study ozone and the H2O2/O3 oxidation system are used to decolorize aqueous solutions of Orange II (Or-II) and Acid Red 27 (AR-27). Investigations are carried out in a semi-batch bubble column reactor. A system of series-parallel reactions is proposed to describe the mechanism of dye oxidation. The stoichiometric ratio for the first reaction is found to be 1 mol dye per mol O3, while the overall ozone demand for both reactions one and two is found to be 5 and 6 moles for Or-II and AR-27 respectively. Molecular and radical kinetics are compared: a radical scavenger, t-butanol, can be added to ensure only the molecular reaction of ozone, or hydrogen peroxide can be supplied through a peristaltic pump, to initiate radical reactivity. Results reveal that colour removal is ensured by direct ozone attack. For both dyes, TOC removal efficiencies of 50 - 60 % are obtained by the action of the hydroxyl free radical. However, this is not improved by addition of H2O2, thus demonstrating that organic species alone ensure HO degrees radical production during ozonation. Both the mass transfer and the ozone reactivity with the dyes are considered to evaluate the kinetic parameters for the molecular pathway.

Integration of chemical and biological oxidation in a SBBR for tannery wastewater treatment

This paper reports the results of an investigation aimed at evaluating the laboratory-scale performance of an innovative process for treating tannery wastewater. In this process, biological degradation, carried out in a sequencing batch biofilm reactor (SBBR), is combined with chemical oxidation by ozone. Tannery wastewater treatment was carried out, at laboratory scale, on a real primary effluent coming from a centralised plant treating wastewater produced by a large tannery district in Northern Italy. SBBR performance both without and with ozonation, was assessed with very satisfactory results. In particular, in the latter instance the recorded COD, TKN and TSS average removals, (96%), (92%) and (98%) respectively, allowed the maximum allowable concentration values fixed by the Italian regulation in force to be achieved without any additional polishing step. During the investigation biofilm properties (biofilm concentration and biofilm density) and flow dynamics aspects (head loss, shear stress, bed porosity) were also studied. A major feature of the process is that, with or without ozonation, it was characterised by very low specific sludge production (0.05 kgVSS/kgCODremoved) and high biofilm density (i.e. 87-122 gVSS/Lsludge) both contributing to a rather high biofilm concentration (i.e. 31-44 gTSS/Lfilter).

Optimized conditions for simultaneous determination of opiates, cocaine and benzoylecgonine in hair samples by GC–MS

The present paper describes a qualitative and quantitative method for the simultaneous detection of opiates, cocaine and benzoylecgonine from human hair samples. Every step of the analytical procedure was studied to find the optimized conditions. Nine different incubation systems were examined. The influence of different pH values of samples on the isolation of analytes from the incubation media by Bond Elut cartridges and the stability of the compounds of interest in the different incubation media and conditions were investigated. The extracting power of different incubation media was studied as well. The phosphate buffer 0.1 N at pH 5 was chosen as the extraction medium in an optimized procedure for simultaneous determination of opiates, cocaine and benzoylecgonine in hair samples. The method developed was validated. Recoveries were 90% for morphine (M), 81% for 6-monoacetylmorphine (6-AM), 90% for codeine (CD), 86% for cocaine (C) and 90% for benzoylecgonine (BE). Relative standard deviation for inter-day precision was better than 12%. The limits of detection resulted as 0.05 ng/mg for M and C, as 0.08 for 6-AM and as 0.2 ng/mg for BE. Forty hair samples collected from drug abusers admitted to centers for detoxification treatment were analyzed obtaining 23 positive results for opiates and/or cocaine. Twelve hair specimens longer than 10 cm were analyzed following a sectional approach. In the six positive cases, it was interesting to find that the 6-AM/M ratio generally decreased for each sample from the proximal segment to the distal segments. Moreover, the 6-AM/M ratio was generally lower than 1 in the intermediate and distal segments.

Ultrastructural changes in the lungs of neonatal rats intratracheally inoculated with meconium

Meconium aspiration syndrome has been for many years an important cause of neonatal respiratory distress in newborn babies and sporadically reported in animals. This investigation was designed to study the ultrastructural and morphometric changes in the lungs of neonatal rats following the intratracheal inoculation of meconium. Seven-day-old Fischer-344 rats (n = 24) were randomly allocated in two groups. One group was intratracheally inoculated with saline solution and the second group received homologous meconium. Neonates were euthanatized at 1, 3 and 7 postinoculation days (PID) and lungs were examined by light and electron microscopy. Saline solution did not induce any ultrastructural changes in the lung. In contrast, meconium induced deciliation, recruitment of neutrophils and pulmonary alveolar macrophages to the bronchoalveolar space, intravascular sequestration of neutrophils and aggregation of platelets at PID 1 and 3. Other ultrastructural changes at PID 1 and 3 included interstitial edema and escape of red cells and fibrin into the alveolar space and interstitium. Interstitial edema and sequestration of neutrophils were responsible for the significant increase in thickness of alveolar septa. At PID 7 there was hyperplasia and enlargement of type II pneumocytes as well as interstitial proliferation of mesenchymal cells with intra-alveolar fibrosis. It was concluded that intratracheal inoculation of meconium in neonatal rats induces acute ultrastructural changes followed by a reparative response.

Interprotein interactions are responsible for the confined diffusion of a G-protein-coupled receptor at the cell surface

The monitoring of the movements of membrane proteins (or lipids) by single-particle tracking enables one to obtain reliable insights into the complex dynamic organization of the plasma membrane constituents. Using this technique, we investigated the diffusional behaviour of a G-protein-coupled receptor. The trajectories of the receptors revealed a diffusion mode combining a short-term rapid confined diffusion with a long-term slow diffusion. A detailed statistical analysis shows that the receptors have a diffusion confined to a domain which itself diffuses, the confinement being due to long-range attractive inter-protein interactions. The existing models of the dynamic organization of the cell membrane cannot explain our results. We propose a theoretical Brownian model of interacting proteins that is consistent with the experimental observations and accounts for the variations found as a function of the domain size of the short-term and long-term diffusion coefficients.

Tannery wastewater treatment by sequencing batch biofilm reactor

The paper reports the results of an investigation aimed to evaluate the performances of an innovative process for treating tannery wastewater. In such a process biological degradation, carried out in a sequencing batch biofilm reactor (SBBR), is combined with chemical oxidation by ozone. The treatment was carried out at laboratory scale on a real primary effluent coming from a centralized plant treating the wastewater of a large tannery district in Northern Italy. SBBR performances without and with ozonation were compared with very satisfactory results particularly in the latter instance when the recorded COD, TKN, and TSS average removals, (96%), (92%), and (98%), respectively, permitted to achieve the fixed limits enforced by Italian regulation without needing any additional polishing step. With or without ozonation, the process that resulted was characterized by a specific sludge production (0.1 kgVSS/kg CODremoved) significantly lower than the values featuring conventional biological systems (i.e., 0.3-0.5 VSS/kg CODremoved). Moreover, as in the reactor the biomass density results were very high, i.e., 98 gVSS/Lsludge, it was possible to achieve and maintain biomass concentration as high as 20 gVSS/L.

[Determination of blood alcohol among aviation personnel: proposed operative protocol]

The problems of the use/abuse of alcohol need a special attention by the Public Authorities, based on the scientific evidences related to the subject. We would like to define in the present paper the procedures for alcohol testing (and drug testing) in the sailors, following the international aviation authorities (ICAO, JAR-OPS-1, FAA) recommendations. A Working Group was established to study both the scientific and the legal aspects of the problems related to alcohol testing in Italy. Experts from the Università "La Sapienza" and from Alitalia studied the alcohol testing issues abroad to set out criteria, guidelines and procedures for random testing in Italy.