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•Novel MMBC fabrication from RM and lignin wastes via one-step pyrolysis in N2 atmosphere.•MMBC exhibited hierarchical porous structure, various functional groups, and metallic ...Fe.•Incorporated RM promoted syngas generation and hydrocarbons decomposition of lignin.•Demonstrated multifunctionality (adsorption, reduction, and catalysis) of MMBC.
This study fabricated a new and multifunctional mixed metal-biochar composites (MMBC) using the mixture of two abundant industrial wastes, red mud (RM) and lignin, via pyrolysis under N2 atmosphere, and its ability to treat wastewater containing various contaminants was comprehensively evaluated. A porous structure (BET surface area = 100.8 m2 g−1) was created and metallic Fe was formed in the MMBC owing to reduction of Fe oxides present in RM by lignin decomposition products during pyrolysis at 700 °C, which was closely associated with the transformation of liquid to gaseous pyrogenic products. The potential application of the MMBC was investigated for the removal of heavy metals (Pb(II) and Ni(II)), oxyanions (As(V) and Cr(VI)), dye (methylene blue), and pharmaceutical/personal care products (para-nitrophenol and pCBA). The aluminosilicate mineral, metallic Fe, and porous carbon matrix derived from the incorporation of RM and lignin contributed to the multifunctionality (i.e., adsorption, chemical reduction, and catalytic reaction) of the MMBC. Thus, engineered biochar composites synthesized from selected industrial wastes can be a potential candidate for environmental applications.
Data acquired by the Fast Auroral Snapshot (FAST) Small Explorer during the 24–25 September 1998 geomagnetic storm have been used to determine the controlling parameters for ionospheric outflows. The ...data were restricted to dayside magnetic local times. Two primary sources of ion outflows are considered: ion heating through dissipation of downward Poynting flux and electron heating through soft electron precipitation. Ion outflows are shown to be correlated with both, although ion outflows have a higher correlation with soft electrons, measured by the density of precipitating electrons. At 4000 km altitude it is found that fi = 1.022 × 109±0.341nep2.200±0.489, where fi is the ion flux in cm−2 s−1 and nep is precipitating electron density, with a correlation coefficient r = 0.855, based on log‐log regression. This scaling law can be mapped to other altitudes by scaling the flux and density with the magnetic field magnitude. The ion flux is also correlated with the Poynting flux, fi = 2.142 × 107±0.242S1.265±0.445, where S is the Poynting flux at 4000 km altitude in mW m−2 and r = 0.721. Either of these two scaling laws can be used specify ion outflow fluxes, since there is a strong intercorrelation between the various parameters. In particular the present study cannot completely eliminate either of the two candidate processes (ion versus electron heating in the ionosphere, corresponding to Poynting flux versus soft electron precipitation). Soft electron precipitation does have a higher correlation coefficient, however, and if possible the precipitating electron density scaling law should be used. Since Poynting flux may be more easily specified in global simulations, for example, this scaling law is a useful alternate. For the interval under study the ion outflows were dominated by oxygen ions, predominantly in the form of ion conics, with a characteristic energy of order 10–30 eV.
Ciprofloxacin-resistant shigellosis outbreaks among men who have sex with men (MSM) have not been reported in Asia. During 3 March to 6 May 2015, the Notifiable Disease Surveillance System detected ...nine non-imported Shigella sonnei infections among human immunodeficiency virus (HIV) -infected Taiwanese MSM. We conducted a molecular epidemiological investigation using a 1 : 5 matched case–control study and laboratory characterizations for the isolates. Of the nine patients, four reported engagement in oral–anal sex before illness onset. Shigellosis was associated with a syphilis report within 12 months (adjusted odds ratio (aOR) 8.6; 95% CI 1.05–70.3) and no HIV outpatient follow-up within 12 months (aOR 22.3; 95% CI 2.5–201). Shigella sonnei isolates from the nine patients were all ciprofloxacin-resistant and the resistance was associated with S83L and D87G mutations in gyrA and S80I mutation in parC. The nine outbreak isolates were discriminated into two closely related pulsed-field gel electrophoresis (PFGE) genotypes and seven 8-locus multilocus variable-number tandem repeat analysis (MLVA8) types that suggest multiple sources of infections for the outbreak and possible under-recognition of infection among Taiwanese MSM. The outbreak isolates were characterized to be variants of the intercontinentally transmitted SS18.1 clone, which falls into the globally prevalent phylogenetic sub-lineage IIIb. Inter-database pattern similarity searching indicated that the two PFGE genotypes had emerged in the USA and Japan. The epidemiological characteristics of this outbreak suggest roles of risky sexual behaviours or networks in S. sonnei transmission. We urge enhanced surveillance and risk-reduction interventions regionally against the interplay of HIV and shigellosis among MSM.
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•Microwave activated biochar (MAB) as biosorbent for landfill leachate treatment.•MAB was produced via single-step microwave steam activation (STMSA) method.•The MAB showed comparable ...adsorption capacity with commercial activated carbon.•Optimum parameters: m =0.4 g/L, t =24 h, pH = 2–3, Co =660 mg/L, qe =595 mg/g, COD removal = 65 %.•The data fitted Freundlich isotherm and pseudo-second order kinetic models.
Improving the sustainability and cost-effectiveness of biochar production is crucial to meet increased global market demand. Here, we developed a single-step microwave steam activation (STMSA) as a simplified yet efficient method to produce microwave activated biochar (MAB) from waste palm shell (WPS). The STMSA recorded a higher heating rate (70 °C/min) and higher conversion (45 wt%) of WPS into highly microporous MAB (micropore surface area of 679.22 m2/g) in contrast with the conventional heating approach (≤ 12−17 wt%). The MAB was then applied as biosorbent for hazardous landfill leachate (LL) treatment and the adsorption performance was compared with commercial activated carbon under different pH, adsorbent quantity, adsorbate concentrations, and contact times. The MAB demonstrated high adsorption capacity, achieving maximum adsorption efficiency at 595 mg/g and 65 % removal of chemical oxygen demand (COD) with 0.4 g/L of adsorbent amount under optimal acidic conditions (pH ≈ 2–3) after 24 h of contact time. The Freundlich isotherm and pseudo second-order kinetic models were well-fitted to explain the equilibrium adsorption and kinetics. The results indicate the viability of STMSA as a fast and efficient approach to produce activated biochar as a biosorbent for the treatment of hazardous landfill leachate.
AbstractGabions are the most commonly adopted cushion layer for shielding rigid debris-resisting barriers against boulder impact. Despite the prevalent use of gabions, they comprise heavy rock ...fragments that are not easily transported up steep natural terrain. The advent of using light-weight cellular glass as an alternative cushion layer provides an innovative approach for absorbing impact energy. However, a lack of insight on their load attenuation characteristics has hindered its potential implementation. In this study, cellular glass was subjected to successive impacts to replicate the dynamic loading of boulders by using a large-scale pendulum setup. Results reveal that for a single impact at 70 kJ, crushing exhibited by cellular glass leads to 25% lower impact force compared to gabions, which rely predominantly on rock fragment rearrangement to absorb energy. However, gabions exhibit more effective load spreading, with a diffusion angle three times greater than cellular glass. To ensure robust designs for cellular glass, the Johnson’s damage number is proposed to quantify the plastic deformation and to improve estimates of the cushioning efficiency represented by the load-reduction factor (Kc) used in current design.
ABSTRACT The Large Binocular Telescope Interferometer (LBTI) is a versatile instrument designed for high angular resolution and high-contrast infrared imaging (1.5-13 m). In this paper, we focus on ...the mid-infrared (8-13 m) nulling mode and present its theory of operation, data reduction, and on-sky performance as of the end of the commissioning phase in 2015 March. With an interferometric baseline of 14.4 m, the LBTI nuller is specifically tuned to resolve the habitable zone of nearby main-sequence stars, where warm exozodiacal dust emission peaks. Measuring the exozodi luminosity function of nearby main-sequence stars is a key milestone to prepare for future exo-Earth direct imaging instruments. Thanks to recent progress in wavefront control and phase stabilization, as well as in data reduction techniques, the LBTI demonstrated in 2015 February a calibrated null accuracy of 0.05% over a 3 hr long observing sequence on the bright nearby A3V star β Leo. This is equivalent to an exozodiacal disk density of 15-30 zodi for a Sun-like star located at 10 pc, depending on the adopted disk model. This result sets a new record for high-contrast mid-infrared interferometric imaging and opens a new window on the study of planetary systems.
Despite the growing recognition of a host genetic effect on shaping gut microbiota composition, the genetic determinants of oral microbiota remain largely unexplored, especially in the context of ...oral diseases. Here, we performed a microbiome genome-wide association study in 2 independent cohorts of patients with oral squamous cell carcinoma (OSCC, n = 144 and 67) and an additional group of noncancer individuals (n = 104). Besides oral bacterial dysbiosis and signatures observed in OSCC, associations of 3 loci with the abundance of genus-level taxa and 4 loci with β diversity measures were detected (q < 0.05) at the discovery stage. The most significant hit (rs10906082 with the genus Lachnoanaerobaculum, P = 3.55 × 10–9 at discovery stage) was replicated in a second OSCC cohort. Moreover, the other 2 taxonomical associations, rs10973953 with the genus Kingella (P = 1.38 × 10–9) and rs4721629 with the genus Parvimonas (P = 3.53 × 10–8), were suggestive in the meta-analysis combining 2 OSCC cohorts. Further pathway analysis revealed that these loci were enriched for genes in regulation of oncogenic and angiogenic responses, implicating a genetic anchor to the oral microbiome in estimation of casual relationships with OSCC. Our findings delineate the role of host genotypes in influencing the structure of oral microbial communities.
Genetic and acquired factors are thought to be interrelated and imperative to estimate the risk and prognosis of oral squamous cell carcinoma (OSCC). HOX transcript antisense intergenic RNA (HOTAIR) ...plays crucial roles in gene regulation and is regulated in a variety of cancers. Polymorphisms in HOTAIR have been recently linked to the predisposition to diverse malignancies. In the present study, we aimed to evaluate the influences of HOTAIR gene polymorphisms, combined with environmental triggers, on the susceptibility to oral tumorigenesis. Four single-nucleotide polymorphisms of the HOTAIR gene— rs920778, rs1899663, rs4759314, and rs12427129—were tested in 1,200 control participants and 907 patients with OSCC. We detected a significant association of rs1899663 with the risk of OSCC (adjusted odds ratio, 2.227; 95% confidence interval 95% CI, 1.197 to 4.146; P = 0.012) after adjustment for 3 potential confounders: smoking, betel quid chewing, and alcohol consumption. In further analyses where habitual exposure to each of 3 environmental factors was excluded, we found that, in addition to rs1899663, non–betel quid users who carried the polymorphic allele of rs920778 were more prone to develop OSCC than were those homozygous for wild-type allele (TC: odds ratio OR, 1.472; 95% CI, 1.069 to 2.029; P = 0.018; TC+CC: OR, 1.448; 95% CI, 1.060 to 1.977; P = 0.020). Moreover, in exploring the relationship between HOTAIR gene polymorphisms and the clinical status of only patients with OSCC who were non–betel quid chewers (excluding the advanced clinical stage), we found that rs920778 and rs4759314 were correlated with the development of large-size tumors (OR, 1.891; 95% CI, 1.027 to 3.484; P = 0.04) and increased lymph node metastasis (OR, 4.140; 95% CI, 1.785 to 9.602; P = 0.001), respectively. Further functional assessments link rs920778 to the regulation of HOTAIR expression and epigenetic status. Our results reveal an interactive effect of HOTAIR gene polymorphisms and betel quid chewing on the development and progression of oral cancer.
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