A recent Monographs Working Group of the International Agency for Research on Cancer concluded that there is limited evidence for a causal association between exposure to asbestos and stomach cancer.
...We performed a meta-analysis to quantitatively evaluate this association. Random effects models were used to summarise the relative risks across studies. Sources of heterogeneity were explored through subgroup analyses and meta-regression.
We identified 40 mortality cohort studies from 37 separate papers, and cancer incidence data were extracted for 15 separate cohorts from 14 papers. The overall meta-SMR for stomach cancer for total cohort was 1.15 (95% confidence interval 1.03-1.27), with heterogeneous results across studies. Statistically significant excesses were observed in North America and Australia but not in Europe, and for generic asbestos workers and insulators. Meta-SMRs were larger for cohorts reporting a SMR for lung cancer above 2 and cohort sizes below 1000.
Our results support the conclusion by IARC that exposure to asbestos is associated with a moderate increased risk of stomach cancer.
The presence of organic micropollutants (OMPs) in natural water bodies has become an emerging concern due to their fast dissemination into natural water sources, high persistence, ubiquitous nature, ...and detrimental impact on the environment and human health. This study evaluated the Membrane Aerated Biofilm Reactor (MABR) efficiency in the removal of 13 OMPs commonly reported in water. Results demonstrated that OMPs removal is dependent on biofilm thickness and bacterial cell density, microbial community composition and physicochemical properties of OMPs. Effective removals of ammonium and organic carbon (COD, >50%), acetaminophen (70%) and triclosan (99%) were obtained even at early stages of biofilm development (thickness < 0.33 mm, 2.9 ×105 cell mL−1). An increase in biofilm thickness and cell density (1.02 mm, 2.2 ×106 cell mL−1) enhanced the system performance. MABR achieved over 90% removal of nonpolar, hydrophobic and hydrophilic OMPs and 22–69% removal of negatively charged and acidic OMPs. Relative abundances of Zoogloea, Aquabacterium, Leucobacter, Runella, and Paludilbaculum bacteria correlated with the removal of certain OMPs. In addition, MABR achieved up to 96% nitrification and 80% overall COD removal by the end of the experiment. The findings from this study demonstrated MABRs to be a feasible option to treat municipal wastewater polluted by OMPs.
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•Optimal MABR performance obtained at thicknesses > 0.87 mm and 1.2 × 106 cells mL-1.•MABR achieved > 90% removal of nonpolar, uncharged OMPs included in Group 1.•MABR achieved 22–69% removal of acidic, ionic, hydrophobic OMPs of Group 2.•The MABR removed less than 15% of highly recalcitrant OMPs included in Group 3.•Zoogloea, Leucobacter, Runella relative abundance correlated with OMP removal.
Enhancement, due to constructive interference through the many possible reaction channels, occurs in two-neutron transfer reactions from a bound system A to a weakly-bound system (A+2), whenever the ...intermediate system is unbound and consists of a continuum with a resonant state. We elucidate this phenomenon in the case of 6He, modeled as two neutrons in the orbitals of an intermediate 5He nucleus, comparing the realistic case of an unbound (A+1) system with an artificially bound case. A properly modeled continuum in these calculations is found to be crucial and leads to significant enhancement due to pairing correlations.
We explore two-particle transfer reactions as a crucial probe of the occurrence of shape coexistence in shape phase transitions. The (t,p) reactions to the ground state and to excited 0+ states are ...calculated for the isotope chain of even-even Zirconium isotopes starting from stable nuclei up to beyond current experimental limits. Two-particle spectroscopic factors derived from Monte Carlo Shell Model calculations are used, together with the sequential description of the two-particle transfer reaction mechanism. The calculation shows a clear signature for a shape phase transition between 98Zr and 100Zr, which displays coexistence of a deformed ground state with an excited spherical 0+ state. Furthermore, we show that there is a qualitative difference with respect to the case of a normal shape phase transition that can be discriminated with two-neutron transfer reactions.
Quantum Phase Transitions arising in algebraic and collective models of nuclear structure are reviewed. The concept of quantum phases and phase transitions is described as well as those of critical ...point symmetries and quasi-dynamical symmetries. Algebraic and collective models are compared and the connections between them are explored. Differences between even–even and odd–even systems are discussed. Several applications of critical point symmetries are given in both the even and odd sectors. Details of the spherical to γ−unstable and spherical to axially deformed quantum shape phase transition are covered in some detail as well as other transitions and alternative approaches.
Bisphosphonates (BPs) are widely used to treat several metabolic and oncological diseases affecting the skeletal system. Despite BPs’ well-known therapeutic potential, they also displayed important ...side effects, among which is BPs-related osteonecrosis of the jaw, by targeting osteoclast activities, osteoblast, and osteocyte behavior. The aim of this study is to evaluate the biological effects of zoledronic acid (ZOL) in an in vitro model of periodontal ligament stem cells (PDLSCs) by using an experimental setting that resembles the in vivo conditions. PDLSCs were treated with different concentrations of ZOL ranging from 0.1 to 5 μM. The effects of ZOL exposure were evaluated on cell viability via 3-4,5-Dimethylthiaoly-2,5-diphenyltetrazolium bromide (MTT), cell cycle analysis, apoptosis detection, and immunofluorescence. Quantitative real-time polymerase chain reaction (PCR), colorimetric detection of alkaline phosphatase activity, and Alizarin Red S staining were performed to investigate the osteogenic potential of PDLSCs exposed to ZOL. MTT analysis showed that the viability of PDLSCs exposed to ZOL concentration ≥1.5 μM for 3 and 6 days was significantly lower (P < 0.001) than that of untreated cells. The percentage of apoptotic cells was significantly higher in PDLSCs exposed for 4 days to ZOL at 2 μM (P < 0.01) and 5 μM (P < 0.001) when compared to the control. Moreover, ZOL treatment (3 days) accounted for alterations in cell cycle distribution, with an increase in the proportion of cells in G0/G1 phase and a reduction in the proportion of cells in S phase. Chronic exposure (longer than 7 days) of PDLSCs to ZOL accounted for the downregulation of ALP, RUNX2, and COL1 genes at all tested concentrations, which fit well with the reduced alkaline phosphatase activity reported after 7 and 14 days of treatment. Reduced Col1 deposition in the extracellular matrix was reported after 14 days of treatment. Increased calcium deposits were observed in treated cells when compared to the control cultures. In conclusion, chronic exposure to 1 μM ZOL induced significant reduction of osteogenic differentiation, while ZOL concentrations ≥1.5 μM are required to impair PDLSCs viability and induce apoptosis.
The majority of human societies allow polygynous marriage, and the prevalence of this practice is readily understood in evolutionary terms. Why some societies prescribe monogamous marriage is however ...not clear: current evolutionary explanations--that social monogamy increases within-group co-operation, giving societies an advantage in competition with other groups--conflict with the historical and ethnographic evidence. We show that, within the framework of inclusive fitness theory, monogamous marriage can be viewed as the outcome of the strategic behaviour of males and females in the allocation of resources to the next generation. Where resources are transferred across generations, social monogamy can be advantageous if partitioning of resources among the offspring of multiple wives causes a depletion of their fitness value, and/or if females grant husbands higher fidelity in exchange for exclusive investment of resources in their offspring. This may explain why monogamous marriage prevailed among the historical societies of Eurasia: here, intensive agriculture led to scarcity of land, with depletion in the value of estates through partitioning among multiple heirs. Norms promoting high paternity were common among ancient societies in the region, and may have further facilitated the establishment of social monogamy. In line with the historical and ethnographic evidence, this suggests that monogamous marriage emerged in Eurasia following the adoption of intensive agriculture, as ownership of land became critical to productive and reproductive success.
Age-related cognitive impairment and dementia are an increasing societal burden. Epidemiological studies indicate that lifestyle factors, e.g. physical, cognitive and social activities, correlate ...with reduced dementia risk; moreover, positive effects on cognition of physical/cognitive training have been found in cognitively unimpaired elders. Less is known about effectiveness and action mechanisms of physical/cognitive training in elders already suffering from Mild Cognitive Impairment (MCI), a population at high risk for dementia. We assessed in 113 MCI subjects aged 65-89 years, the efficacy of combined physical-cognitive training on cognitive decline, Gray Matter (GM) volume loss and Cerebral Blood Flow (CBF) in hippocampus and parahippocampal areas, and on brain-blood-oxygenation-level-dependent (BOLD) activity elicited by a cognitive task, measured by ADAS-Cog scale, Magnetic Resonance Imaging (MRI), Arterial Spin Labeling (ASL) and fMRI, respectively, before and after 7 months of training vs. usual life. Cognitive status significantly decreased in MCI-no training and significantly increased in MCI-training subjects; training increased parahippocampal CBF, but no effect on GM volume loss was evident; BOLD activity increase, indicative of neural efficiency decline, was found only in MCI-no training subjects. These results show that a non pharmacological, multicomponent intervention improves cognitive status and indicators of brain health in MCI subjects.
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