[Transformation Characteristics of Dissolved Organic Matter During UV/Chlorine Treatment of Municipal Secondary Effluent].

As an emerging advanced oxidation technology, UV/chlorine treatment is capable of effectively oxidizing various organic pollutants. Till now, the transformation of dissolved effluent organic matter (dEfOM) in real wastewater during UV/chlorine treatment remains unclear. In this study, ultraviolet and fluorescence spectroscopy were combined with Fourier transform ion cyclotron resonance mass spectrometry to probe the transformation of dEfOM in two municipal secondary effluents during UV/chlorine treatment. Meanwhile, the newly formed chlorinated byproducts (Cl-BPs) are particularly concerned. Generally, aromatic compounds and fluorescent components could be readily removed after UV/chlorine treatment, and most of the dEfOM underwent transformation rather than mineralization. Protein-like components, which accounted for the largest proportion of fluorescent components, were subject to a preferential reaction. UV/chlorine treatment could result in the degradation of CHOS compounds and the formation of CHO compounds. During this process, unsaturated and reduced compounds of large molecules were preferentially removed, whereas saturated and oxidized compounds with low molecular weight were produced. Moreover, the concentrations of trihalomethanes and haloacetic acids increased substantially after UV/chlorine treatment. In total, 255 and 133 Cl-BPs were detected in the respective effluents after UV/chlorine treatment. In addition, 12 and 43 possible precursor-Cl-BPs pairs were identified, respectively, based on electrophilic substitution and addition reactions by means of mass difference analysis. This study is expected to provide fundamental information for practical application of the UV/chlorine treatment process.

Analysis of hospitalization costs and length of stay for oral cancer patients undergoing surgery: Evidence from Hunan, China.

OBJECTIVE: To provide information about hospitalization costs and length of stay (LOS) for inpatients undergoing oral cancer (OC) surgery, and to investigate the association of hospitalization costs and LOS with demographics, tumor subsite, surgery-related and hospital characteristics. METHODS: Data extracted from Chinese National Health Statistics Network Reporting System database in Hunan, China during 2017-2019 were analyzed using quantile regression models. RESULTS: A total of 6,420 OC patients undergoing surgery were identified. After controlling potential compounding variables, the median hospitalization cost was significantly higher in male than in female patientsby $515.70 at the median (p < 0.001). Patients aged over 60 hadsignificantly less costs by $294.85 at the meanthan did those below 60, while no differenceof LOS existed across age. OC patients with neck dissection had significantly higher costs by $1,983.33 at the median than those without (P < 0.001). Regional flaps were the most economical, with lower costs than free flaps by $3,084 (P < 0.001) and the pectoralis major myocutaneous flap (PMMF) by $549.45 (P < 0.001) at the median. CONCLUSION: Male is a significant driver of hospitalization costs and LOS for OC, and age over 60 is associated with lower costs, but not with LOS. Mouth primary site is associated with the highest costs and LOS, while lip primary site the lowest. Absence of neck dissection in early-stage OC can significantly reduce costs and LOS, but its oncological validity needs more evidence. Regional flaps are less expensive than free flaps and the PMMF for oral reconstruction, and are recommended in select patients.

Do betel quid and areca nut chewing deteriorate prognosis of oral cancer? A systematic review, meta-analysis, and research agenda.

OBJECTIVE: To explore the correlations between the habit of betel quid and areca nut (BQ-AN) chewing and the prognosis of oral cancer (OC). METHODS: We performed a systematic review and meta-analysis to clarify this issue. Data searches were performed using PubMed, Web of Science, Epistemonikos, and Embase databases through November 2019. The primary outcome was the difference in the prognosis of OC between BQ-AN chewers and non-chewers, measured in terms of 5-year overall survival (OS) and 5-year disease-specific survival (DSS) log (HR) reported in articles. The pooled HR with 95% CI of 5-year OS and 5-year DSS was calculated using a fixed-effects model. RESULTS: Ten articles with eleven OS or DSS survival studies (one of the articles contained two studies), which were published between 2003 and 2017, were eligible for inclusion in the present study. All the 11 studies were observational studies, among which 10 were retrospective and 1 was prospective. One study measured both OS and DSS. Eight studies, with a total of 2,761 patients, used 5-year OS as the primary endpoint and four studies, with a total of 2,551 patients, used 5-year DSS. Overall, the pooled HR evaluating BQ-AN chewers was 1.26 (95% CI: 1.09-1.46) for 5-year OS and 1.40 (95% CI: 1.15-1.70) for 5-year DSS, compared with non-chewers. There was a significant association between BQ-AN chewing and OC survival. CONCLUSIONS: Betel quid and areca nut chewing is significantly associated with poor prognosis in patients with OC.

Functional genes (dsr) approach reveals similar sulphidogenic prokaryotes diversity but different structure in saline waters from corroding high temperature petroleum reservoirs.

Oil reservoirs and production facilities are generally contaminated with H2S resulting from the activity of sulphidogenic prokaryotes (SRP). Sulphidogenesis plays a major role in reservoir souring and microbial influenced corrosion in oil production systems. In the present study, sulphidogenic microbial diversity and composition in saline production fluids retrieved from three blocks of corroding high temperature (79 ~ 95 °C) oil reservoirs with high sulfate concentrations were investigated by phylogenetic analyses of gene fragments of the dissimilatory sulfite reductase (dsr). Analysis of dsr gene fragments revealed the presence of several clusters of sulphidogenic prokaryotes that cover the orders Desulfovibrionales (Desulfovibrio, Desulfomicrobium thermophilum), Desulfobacterales (Desulfobacterium, Desulfosarcina, Desulfococcus, Desulfotignum, Desulfobotulus, Desulfobulbus), Syntrophobacterales (Desulfacinum, Thermodesulforhabdus, Desulforhabdus), Clostridiales (Desulfotomaculum) and Archaeoglobales (Archaeoglobus); among which sequences affiliated to members of Desulfomicrobium, Desulfotomaculum and Desulfovibrio appeared to be the most encountered genera within the three blocks. Collectively, phylogenetic and non-metric multidimensional scaling analyses indicated similar but structurally different sulphidogenic prokaryotes communities within the waters retrieved from the three Blocks. This study show the diversity and composition of sulphidogenic prokaryotes that may play a role in the souring mediated corrosion of the oilfield and also provides a fundamental basis for further investigation to control oil reservoir souring and corrosion of pipelines and topside installations.