Impacts of regional socioeconomic statuses and global events on solid waste research reflected in six waste-focused journals

The research pertaining to solid waste is undergoing extensive advancement, thereby necessitating a consolidation and analysis of its research trajectories. The existing biblio-studies on solid waste research (SWR) lack thorough analyses of the factors influencing its trends. This article presents an innovative categorization framework that categorizes publications from six SWR journals utilizing Source Latent Dirichlet Allocation. First analyse changes in publication numbers across main categories, subcategories, journals, and regions, providing a macro-level study of SWR. Temporal analysis of keywords supplements a micro-level study of SWR, which highlights that emerging technologies with low Technology Readiness Level receive significant attention, while studies on widespread technologies are diminishing. Additionally, this study demonstrates the substantial influence of socioeconomic factors and previous SWR publications on current and future SWR trends. Finally, the article confirms the impact of global events on SWR trends by examining the structural breakpoints of SWR and their correlation with global events.

Categorization of leaching behaviors of elements from commercially treated incineration bottom ash in Singapore

Leaching of potentially hazardous substances, especially the heavy metals from Incineration Bottom Ash (IBA) is a major problem in its recyclable usage. To address this concern, treatment of IBA is indispensable before it can be reused. IBA subjected to laboratory-scale treatment typically yields clearer conclusions in terms of leaching behaviors, benefiting from the controlled laboratory environment. However, the leaching behaviors of commercially treated IBA appear to be more ambiguous due to the complex and comprehensive nature of industrial-scale treatments, where multiple treatment techniques are involved concurrently. Furthermore, treatment efficiencies vary among different plants. In this study, three types of commercially treated IBA were sampled from leading waste treatment companies in Singapore. Characterization and leaching tests were performed on the treated IBAs in both standardized and modified manners to simulate various scenarios. Besides deionized water, artificial seawater was used as a leachant in leaching tests for simulating seawater intrusion. The results reveal the promoting effect of seawater on the leaching levels of several elements from three types of treated IBA, which may require special attention for IBA application and landfill near the coast. Furthermore, the elements examined in these three types of commercially treated IBA generally comply with the non-hazardous waste acceptance criteria outlined in Council Decision, 2003/33/EC (2003), except Sb. By combining two leaching tests, the elements were categorized into different types of leaching behavior, making it possible to prepare and respond to the concerning leaching scenarios in future engineering applications.

Aging Increases Global Annual Food Greenhouse Gas Emissions up to 300 Million Tonnes by 2100

The dietary preferences of the elderly population exhibit distinct variations from the overall averages in most countries, gaining increasing significance due to aging demographics worldwide. These dietary preferences play a crucial role in shaping global food systems, which will result in changed environmental impacts in the future such as greenhouse gas (GHG) emissions. We present a quantitative evaluation of the influence of population aging on the changes in GHG emissions from global food systems. To achieve this, we developed regional dietary coefficients (DCs) of the elderly based on the Global Dietary Database (GDD). We then reconciled the GDD with the dataset from the Food and Agriculture Organization of the United Nations (FAO) to calculate the food GHG emissions of the average population in each of the countries. By applying the DCs, we estimated the national food GHG emissions and obtained the variations between the emissions from aged and average populations. We employed a modified version of the regional integrated model of climate and the economy model (RICE) to forecast the emission trends in different countries based on FAO and GDD data. This integrated approach allowed us to evaluate the dynamic relationships among aging demographics, food consumption patterns, and economic developments within regions. Our results indicate that the annual aging-embodied global food GHG emissions will reach 288 million tonnes of CO2 equivalent (Mt CO2e) by 2100. This estimation is crucial for policymakers, entrepreneurs, and researchers as it provides insights into a potential future environmental challenge and emphasizes the importance of sustainable food production and consumption strategies to GHG emission mitigations associated with aging dietary patterns.

Photothermal-Controllable Microneedles with Antitumor, Antioxidant, Angiogenic, and Chondrogenic Activities to Sequential Eliminate Tracheal Neoplasm and Reconstruct Tracheal Cartilage

The optimal treatment for tracheal tumors necessitates sequential tumor elimination and tracheal cartilage reconstruction. This study introduces an innovative inorganic nanosheet, MnO2 /PDA@Cu, comprising manganese dioxide (MnO2 ) loaded with copper ions (Cu) through in situ polymerization using polydopamine (PDA) as an intermediary. Additionally, a specialized methacrylic anhydride modified decellularized cartilage matrix (MDC) hydrogel with chondrogenic effects is developed by modifying a decellularized cartilage matrix with methacrylic anhydride. The MnO2 /PDA@Cu nanosheet is encapsulated within MDC-derived microneedles, creating a photothermal-controllable MnO2 /PDA@Cu-MDC microneedle. Effectiveness evaluation involved deep insertion of the MnO2 /PDA@Cu-MDC microneedle into tracheal orthotopic tumor in a murine model. Under 808 nm near-infrared irradiation, facilitated by PDA, the microneedle exhibited rapid overheating, efficiently eliminating tumors. PDA's photothermal effects triggered controlled MnO2 and Cu release. The MnO2 nanosheet acted as a potent inorganic nanoenzyme, scavenging reactive oxygen species for an antioxidant effect, while Cu facilitated angiogenesis. This intervention enhanced blood supply at the tumor excision site, promoting stem cell enrichment and nutrient provision. The MDC hydrogel played a pivotal role in creating a chondrogenic niche, fostering stem cells to secrete cartilaginous matrix. In conclusion, the MnO2 /PDA@Cu-MDC microneedle is a versatile platform with photothermal control, sequentially combining antitumor, antioxidant, pro-angiogenic, and chondrogenic activities to orchestrate precise tracheal tumor eradication and cartilage regeneration.

Hydrolytic degradation and biodegradation of polylactic acid electrospun fibers

Increased use of bioplastics, such as polylactic acid (PLA), helps in reducing greenhouse gas emissions, decreases energy consumption and lowers pollution, but its degradation efficiency has much room for improvement. The degradation rate of electrospun PLA fibers of varying diameters ranging from 0.15 to 1.33 μm is measured during hydrolytic degradation under different pH from 5.5 to 10, and during aerobic biodegradation in seawater supplemented with activated sewage sludge. In hydrolytic conditions, varying PLA fiber diameter had significant influence over percentage weight loss (W%L), where faster degradation was achieved for PLA fibers with smaller diameter. W%L was greatest for PLA-5 > PLA-12 > PLA-16 > PLA-20, with average W%L at 30.7%, 27.8%, 17.2% and 14.3% respectively. While different pH environment does not have a significant influence on PLA degradation, with W%L only slightly higher for basic environments. Similarly biodegradation displayed faster degradation for small diameter fibers with PLA-5 attaining the highest degree of biodegradation at 22.8% after 90 days. Hydrolytic degradation resulted in no significant structural change, while biodegradation resulted in significant hydroxyl end capping products on the PLA surface. Scanning electron microscopy (SEM) imaging of degraded PLA fibers showed a deteriorated morphology of PLA-5 and PLA-12 fibers with increased adhesion structures and irregularly shaped fibers, while a largely unmodified morphology for PLA-16 and PLA-20.

Unveiling the Microfiber Release Footprint: Guiding Control Strategies in the Textile Production Industry

Microplastic fibers from textiles have been known to significantly contribute to marine microplastic pollution. However, little is known about the microfiber formation and discharge during textile production. In this study, we have quantified microfiber emissions from one large and representative textile factory during different stages, spanning seven different materials, including cotton, polyester, and blended fabrics, to further guide control strategies. Wet-processing steps released up to 25 times more microfibers than home laundering, with dyeing contributing to 95.0% of the total emissions. Microfiber release could be reduced by using white coloring, a lower dyeing temperature, and a shorter dyeing duration. Thinner, denser yarns increased microfiber pollution, whereas using tightly twisted fibers mitigated release. Globally, wet textile processing potentially produced 6.4 kt of microfibers in 2020, with China, India, and the US as significant contributors. The study underlined the environmental impact of textile production and the need for mitigation strategies, particularly in dyeing processes and fiber choice. In addition, no significant difference was observed between the virgin polyesters and the used ones. Replacing virgin fibers with recycled fibers in polyester fabrics, due to their increasing consumption, might offer another potential solution. The findings highlighted the substantial impact of textile production on microfiber released into the environment, and optimization of material selection, knitting technologies, production processing, and recycled materials could be effective mitigation strategies.

Molecular insight into DOM fate using EEM-PARAFAC and FT-ICR MS and concomitant heavy metal behaviors in biologically treated landfill leachate during coagulation: Al speciation dependence

Various combined processes with pre-coagulation have been developed for biologically treated landfill leachate, but the microscopic-level processes occurring during coagulation remain largely unknown. Herein, dissolved organic matter (DOM) fate using fluorescence excitation emission matrix spectroscopy combined with parallel factor analysis and electrospray ionization coupled Fourier transform-ion cyclotron resonance mass spectrometry and concomitant heavy metal (HM) behaviors were explored at the molecular level. In addition, AlCl3 and two polyaluminum chloride (PACl) species (dominated by [AlO4Al12(OH)24(H2O)12]7+ and [(AlO4)2Al28(OH)56(H2O)26]18+, respectively) were used. The results show that all coagulants are efficient at removing DOM. PACl was found to be advantageous over AlCl3 in overcoming pH fluctuation, which is ascribed to the different dominant mechanisms, namely, entrapment and sweep flocculation for AlCl3 and charge neutralization for PACl. Consequently, PACl was more effective at removing humic substances, usually high-molecular-weight, oxygen-rich and unsaturated, than protein substances. For HM removal, PACl was likewise better and more stable, where As, Cu, Ni, Co and Hg were removed predominantly via adsorption, and Cr, Zn, Pb, Cd and Mn were removed via coprecipitation. Correlation analysis showed that humic substances tended to complex with HMs and be removed synergistically due to the ubiquitous occurrences of aromatic structures and oxygen-containing functional groups.

An automated toxicity based prioritization framework for fast chemical characterization in non-targeted analysis

Identification of environmental pollutants with harmful effects is commonly conducted by non-targeted analysis (NTA) using liquid chromatography coupled with high-resolution mass spectrometry. Prioritization of possible candidates is important yet challenging because of the large number of candidates from MS acquisitions. We aimed to prioritize candidates to the exposure potential of organic chemicals by their toxicity and identification evidence in the matrix. We have developed an R package application, "NTAprioritization.R", for fast prioritization of suspect lists. In this workflow, the identification levels of candidates were first rated according to spectral matching and retention time prediction. The toxicity levels were rated according to candidates' toxicity of different endpoints or ToxPi score. Finally, the various levels of candidates were identified as Tier 1 - 5 descending in priority. For validation, we used this workflow to identify pollutants in a sludge water sample spiked with 28 environmental pollutants. The workflow reduced the candidate list of over 6,982 candidates to a final list of 2,779 compounds and prioritized them to 5 tiers (Tier 1 - 5), including 21 out of 28 spiked standards. Overall, this study shows the added value of an automated prioritization R package for the fast screening of environmental pollutants based on the NTA method.

Stabilization and strengthening of chromium(VI)-contaminated soil via magnesium ascorbyl phosphate (MAP) and phytase addition

Cr(VI) contamination of soil threatens the environment and reduces soil strength. Therefore, both Cr(VI) stabilization and soil reinforcement should be considered in site remediation for future construction. This study investigated a biochemical treatment process using magnesium ascorbyl phosphate (MAP) and phytase. MAP was hydrolyzed via phytase catalysis to produce ascorbic acid (AA) and MgHPO₄·3H₂O precipitation. The AA reduced Cr(VI) into low-toxic Cr(III), which precipitated as Cr(OH)₃ and CrPO₄. More than 90% of the 500 mg/kg Cr(VI) in soil was reduced by 5% MAP (wt% of soil) and 1% phytase (vol/vol of soil water) doses at the geotechnically optimal soil moisture content of 16.8%. The MgHPO₄·3H₂O precipitates filled soil pores and enhanced the unconfined compression strength of treated soil by more than two times. This research reports a novel and practical enzymatically induced phosphate precipitation process for the remediation of Cr(VI)-contaminated soil.

Global void ratio of municipal solid waste for compression indices estimation

Compressibility is one of the important engineering properties of municipal solid waste (MSW) affecting the stability and functionality of a landfill. Although the correlations between MSW properties and compression parameters have been established, they either have low accuracy and small datasets or are only limited to a few specific landfills in a region. In this study, a new method using the initial global void ratio (e₀*) of MSW to estimate the compression indices is developed based on a comprehensive MSW dataset. The dataset consists of 124 sets (91 laboratory and 33 field) of MSW compression results obtained from 44 studies in 13 countries with different income levels and climate conditions. We categorized MSW as a ternary mixture with biodegradable (B), reinforcing (R), and inert (I) fractions, and suggested average specific gravity values (G_s,B = 1.20, G_s,R = 1.07, and G_s,I = 2.64), respectively. The e₀* values were calculated using the initial dry unit weight (γ_d,0) and ternary composition of MSW. The correlations between the e₀* and the immediate compression index, secondary compression index induced by mechanical creep, and secondary compression index induced by bio-compression of MSW were evidently established. The results are applicable to the MSW with B = 0-79.2 %, R = 0-54.0 %, I = 2.8-100.0 %, and γ_d,0 = 2.0-14.2 kN/m³. A simple flowchart was established to estimate the compression indices and strains of MSW disposed on in landfills and dumpsites in countries with different income levels.

Morphology-Tailored Hydroxyapatite Nanocarrier for Rhizosphere-Targeted Phosphorus Delivery

High hydrophilicity and soil fixation collectively hamper the delivery of phosphorus (P) released from conventional chemical phosphorus fertilizers (CPFs) to plant rhizosphere for efficient uptake. Here, a phosphorus nutrient nanocarrier (PNC) based on morphology-tailored nanohydroxyapatite (HAP) is constructed. By virtue of kinetic control of building blocks with designed calcium phosphate intermediates, rod-like and hexagonal prism-like PNCs are synthesized, both having satisfactory hydrophobicity (water contact angle of 105.4^- 132.9°) and zeta potential (-17.43 to -58.4 mV at pH range from 3 to 13). Greenhouse experiments demonstrate that the P contents increase by up to 183% in maize rhizosphere and up to 16% in maize biomass when compared to the CPF. Due to the water potential gradient driven by photosynthesis and transpiration, both PNCs are stably transported to maize rhizosphere, and they are capable to counteract soil fixation prior to uptake by plant roots. Within the synergies of the HAP morphological characteristics and triggered phosphate starvation response, root anatomy confirms that two pathways are elucidated to enhance plant P replenishment from the PNCs. Together with structure tunability and facile synthesis, our results offer a new nanodelivery prototype to accommodate plant physiological traits by tailoring the morphology of HAP.

Masses and size distributions of mechanically fragmented microplastics from LDPE and EPS under simulated landfill conditions

Landfills contain significant amounts of plastic waste (PW) and microplastics (MPs). However, the contributions of various PW fragmentation processes to the quality and quantity of MPs in landfills are unclear. In this study, LDPE and EPS pieces were mixed with sand to simulate landfilled solid waste, which experienced one-dimensional abiotic compression under vertical stress of 100-800 kPa for 1-300 days. The generated MPs were stained and quantified with a fluorescent microscope. The numbers and masses of the fragmented MPs increase with the increasing compression stress and duration following linear or exponential trends. EPS has a lower stiffness than LDPE, thus generates more MPs under the same compression conditions. Stress-dependent and time-dependent fragmentation mechanisms are distinguished, the former is driven by sand-plastic porosity reduction and the latter is due to microscopic interfacial creep with minimal porosity reduction. Most of the mechanically fragmented MPs have diameters < 100 µm. The MPs size distributions follow an established power-law model, which are dependent on stress, duration, porosity reduction, and fragmentation mechanism. Our results serve as conservative estimations on long-term MPs generation in real landfills, which provide confirmative and quantitative evidence to support the previous studies reporting the varied MPs abundances and properties within landfills.

Cradle-to-grave emissions from food loss and waste represent half of total greenhouse gas emissions from food systems

Global greenhouse gas (GHG) emissions from food loss and waste (FLW) are not well characterized from cradle to grave. Here GHG emissions due to FLW in supply chain and waste management systems are quantified, followed by an assessment of the GHG emission reductions that could be achieved by policy and technological interventions. Global FLW emitted 9.3 Gt of CO₂ equivalent from the supply chain and waste management systems in 2017, which accounted for about half of the global annual GHG emissions from the whole food system. The sources of FLW emissions are widely distributed across nine post-farming stages and vary according to country, region and food category. Income level, technology availability and prevailing dietary pattern also affect the country and regional FLW emissions. Halving FLW generation, halving meat consumption and enhancing FLW management technologies are the strategies we assess for FLW emission reductions. The region-specific and food-category-specific outcomes and the trade-off in emission reductions between supply chain and waste management are elucidated. These insights may help decision makers localize and optimize intervention strategies for sustainable FLW management.

Applications of crushing and grinding-based treatments for typical metal-containing solid wastes: Detoxification and resource recovery potentials

Metal-containing solid wastes can induce serious environmental pollution if managed improperly, but contain considerable resources. The detoxification and resource recoveries of these wastes are of both environmental and economic significances, being indispensable for circular economy. In the past decades, attempts have been made worldwide to treat these wastes. Crushing and grinding-based treatments have been increasingly applied, the operating apparatus and parameters of which depend on the waste type and treatment purpose. Based on the relevant studies, the applications of crushing and grinding on four major types of solid wastes, namely spent lithium-ion batteries (LIBs) cathode, waste printed circuit boards (WPCBs), incineration bottom ash (IBA), and incineration fly ash (IFA) are here systematically reviewed. These types of solid wastes are generated in increasing amounts, and have the potentials to release various organic and inorganic pollutants. Despite of the widely different texture, composition, and other physicochemical properties of the solid wastes, crushing and grinding have been demonstrated to be universally applicable. For each of the four wastes, the technical route that involving crushing and grinding is described with the advantages highlighted. The crushing and grinding serve either mainstream or auxiliary role in the processing of the solid wastes. This review summarizes and highlights the developments and future directions of crushing and grinding-based treatments.

Application of the IoT in the Food Supply Chain─From the Perspective of Carbon Mitigation

With the rising demands on supply chain transparency and food security, the rapid outspread of the Internet of Things (IoT) to improve logistical efficiency, and the rising penetration of sensor technology into daily life, the extensive integration of the IoT in the food sector is well anticipated. A perspective on potential life cycle trade-offs in regard to the type of integration is necessary. We conduct life cycle assessment (LCA) integrated with shelf life-food loss (SL-FL) models, showing an overall 5-fold leverage on carbon reduction, which is diet dependent and a function of income. Meat presents the highest leverage, 35 ± 11-times, owing to its high carbon footprint. Two-thirds (65%) of global sensors (1 billion) engaged in monitoring fruits and vegetables can mitigate less than 7% of the total reduced carbon emissions. Despite the expected carbon emission reductions, widespread adoption of the IoT faces multiple challenges such as high costs, difficulties in social acceptance, and regional variability in technological development. Furthermore, changes in the distribution of transportation resources and dealer service models, requirements regarding the accuracy of sensor data analysis, efficient and persistent operation of devices, development of agricultural infrastructure, and farmer education and training have all increased uncertainty. Nonetheless, the research trend in smart sensors toward smaller chips and the potential integration of machine learning or blockchain as further steps make it possible to leverage these advantages to facilitate market penetration. These insights facilitate the future optimization of the application of IoT sensors for sustainability.

[Differential diagnosis of gallbladder polypoid lesions by micro-flow imaging]

OBJECTIVE

To explore the value of micro-flow imaging (MFI) in evaluating blood flow characteristics and differential diagnosis of gallbladder polypoid lesions.

METHODS

We retrospectively analyzed the clinical data and ultrasound images of 73 patients with gallbladder polypoid lesions, including 24 patients with pathologically confirmed neoplastic polyps (n=24) and 49 with non-neoplastic polyps (n=49). All the patients underwent conventional ultrasound, MFI and contrast enhanced ultrasound (CEUS) before cholecystectomy. The blood flow characteristics of the lesions in color Doppler flow imaging (CDFI) and MFI were compared, and the consistency of the findings by these two modalities with those of CEUS were evaluated by weighted Kappa consistency test. The diagnostic performance of MFI for gallbladder polypoid lesions was assessed.

RESULTS

There were significant differences between MFI and CDFI in the evaluation of blood flow characteristics of gallbladder polypoid lesions (χ²=37.684, P < 0.001). MFI showed better performance than CDFI in displaying the blood flow characteristics of the polyps. The consistency in the findings was 0.118 between CDFI and CEUS and 0.816 between MFI and CEUS. The sensitivity, specificity and accuracy of MFI in distinguishing neoplastic polyps from non-neoplastic polyps were 75.00%, 93.88% and 87.67%, respectively.

CONCLUSION

MFI has a good consistency with CEUS in displaying the blood flow characteristics of gallbladder polypoid lesions and can accurately distinguish neoplastic polyps from non-neoplastic polyps, thus providing new ultrasound diagnostic evidence to support clinical decisions on optimal treatments of gallbladder polypoid lesions.

[Carotid intraplaque neovascularization is correlated with the risk of revascularization following percutaneous coronary intervention]

OBJECTIVE

To investigate the correlation of intraplaque neovascularization (IPN) detected by carotid contrast-enhanced ultrasound (CEUS) with revascularization in patients following percutaneous coronary intervention (PCI).

METHODS

This study was conducted among 105 patients who were followed up for more than 12 months after PCI. All the patients received CEUS examination for assessment of carotid plaque formation and IPN, which were compared between patients with revascularization (REV group, n=27) and those without revascularization (N-REV group, n=78). ROC curve was used to analyze the diagnostic efficacy of CEUS for predicting revascularization. Univariate and multivariate logistic regression analyses were performed to identify the risk factors associated with revascularization.

RESULTS

In the REV group, the IPN score was 0 in 1 (3.7%) patient, 1 in 8 (29.6%) patients, 2 in 15 (55.6%) patients and 3 in 3 (11.1%) patients. Significant differences were noted between REV and N-REV groups in plaque length (15.70±6.93 vs 12.10±6.64, P < 0.05), maximum plaque thickness (3.69±1.12 vs 3.14±1.18, P < 0.05) and IPN (1.74±0.71 vs 0.87±0.63, P < 0.001). IPN score was identified as an independent risk factor for revascularization in patients following PCI, and at the cutoff value of 1.5, its sensitivity, specificity, positive predictive value, and negative predictive value for predicting the occurrence of revascularization were 74%, 89%, 69%, and 91%, respectively, with an AUC of 0.848 (95% CI: 0.703-0.905, P < 0.001).

CONCLUSION

CEUS allows noninvasive and semi-quantitative assessment of neovascularization in carotid artery plaques, and IPN detected by CEUS is correlated with the risk of revascularization in patients following PCI.

Polylactic acid face masks: Are these the sustainable solutions in times of COVID-19 pandemic?

The global massive consumption of disposable face masks driven by the ongoing COVID-19 pandemic has emerged as a blooming disaster to both the land and marine environment that might last for generations. Growing public concerns have been raised over the management and control of this new form of plastic pollution, and one of the proposed sustainable solution is to use renewable and/or biodegradable resources to develop mask materials in order to minimize their environmental impacts. As a representative biodegradable polymer, polylactic acid (PLA) has been proposed as a promising candidate to produce non-woven face masks instead of those fossil-based polymers. To further explore the feasibility of this alternative mask material, the present work aims to study both the hydrolytic and bio-degradation behaviors of pure PLA-derived 3-ply disposable face masks at ambient temperature. Hydrolytic degradability was investigated at different pH conditions of 2, 7 and 13 with the whole piece of face mask soaked for regular timed intervals up to 8 weeks. Weight loss study showed neutral and acidic conditions had minimal effect on PLA masks, but rapid degradation occurred under basic conditions in the first week with a sharp 25% decrease in weight that slowly tapered off, coupled with solution pH dropping from 13 to 9.6. This trend was supported by mechanical property, bacterial filtration efficiency (BFE) and particulate filtration efficiency (PFE) studies. Masks soaked in basic conditions had their modulus and tensile strength dropped by more than 50% after 8 weeks where the middle layer reached 68% and 90% respectively just after 48 h, and BFE and PFE decreased by 14% and 43% respectively after 4 weeks, which was much more significant than those in neutral and acidic conditions. Base degradation was also supported by nuclear magnetic resonance (NMR) and fourier transform infrared (FTIR), which disclosed that only the middle layer undergo major degradation with random chain scission and cleavage of enol or enolate chain ends, while outer and inner layers were much less affected. Scanning electron microscopy (SEM) attributed this observation to thinner PLA fibers for the middle layer of 3-7 μm diameter, which on average is 3 times smaller. This degradation was further supported by gel permeation chromatography (GPC) which saw an increase in lower molecular weight fragment Mw ~ 800 Da with soaking duration. The biodegradation behavior was studied under OECD 301F specification in sewage sludge environment. Similarly, degradation to the middle meltblown layer was more extensive, where the average weight loss and carbon loss was 25.8% and 25.7% respectively, double that of outer/inner spunbond layer. The results showed that the face masks did not completely disintegrate after 8 weeks, but small solubilized fragments of PLA formed in the biodegradation process can be completely mineralized into carbon dioxide without generation of secondary microplastic pollution in the environment. PLA masks are therefore a slightly greener option to consider in times of a pandemic that the world was caught unprepared; however future research on masks could be geared towards a higher degradability material that fully breaks down into non-harmful components while maintaining durability, filtration and protection properties for users.

Selective separation and recovery of lithium, nickel, MnO2, and Co2O3 from LiNi0.5Mn0.3Co0.2O2 in spent battery

The recovery of valuable metals from the LiNi_0·5Mn_0·3Co_0·2O₂ in spent batteries deserves more attention. We report a series of feasible procedures to selectively recover the four metals (Li, Ni, Mn, and Co) using a combination of hydrometallurgical and pyrometallurgyical processes. Firstly, oxalic acid is used to dissolve Li and precipitate the other three metals in oxalate forms. It is found that under the optimal condition, about 98% of the Li is dissolved, and on average 93% of the other three metals are transformed to precipitated oxalates. The oxalates are then transformed to NiO·Mn₂O₃·Co₃O₄ by being calcinated at 723 K under atmospheric environment. The selective recovery of NiO·Mn₂O₃·Co₃O₄ can be achieved by using H₂SO₄ under three different conditions. The first step is to use H₂SO₄ to selectively dissolve CoO from the Co₃O₄. Then the combination of H₂SO₄ and ultrasound is adopted to dissolve NiO, during which the ultrasound destroys the surficial oxide film on the NiO. Afterwards, the Mn₂O₃ is transformed to MnO₂ and Mn²⁺ in heated H₂SO₄. The Co, Ni and Mn ions are dissolved in a sequence, which facilitates their separation and recovery. As the main components of the final residual solids, Co₂O₃ and MnO₂ present in distinctly different sizes and shapes, which are beneficial for their separation and direct usage.

Sequestration of free and chelated Ni(II) by structural Fe(II): Performance and mechanisms

Ni(II) and chelated Ni(II) in wastewater are of environmental concern. This study explores the sequestration potential of structural Fe(II) in solid phase (≡Fe(II)) on Ni(II) and EDTA-Ni(II) using freshly prepared ferrous hydroxyl complex (FHC) as the Fe(II)-bearing mineral. The 1 mM Ni(II) could be completely sequestrated in 20 min by 3 mM FHC, although the sequestrated Ni(II) was partially released after 20 min. It is calculated that up to 156 mg Ni(II)/g Fe(II) can be sequestrated by ≡Fe(II) under neutral pH and anaerobic condition. According to the characterizations of the solid products, the large surface area for Ni(II) adsorption and the high ≡Fe(II) reduction capacity for Ni(II) reduction are the main contributors to the Ni(II) sequestration. After the reaction, the FHC is transformed to stable Fe-Ni layered double hydroxides. The concomitant ions can be either promotional or inhibitory to the sequestration performance depending on the ion type. The combination of FHC and Fe(III) can effectively sequestrate EDTA-Ni(II), whereas FHC alone has a low efficiency. Fe(III) substitutes Ni(II) from the EDTA-Ni(II), benefiting the subsequent Ni(II) sequestration by ≡Fe(II). This study demonstrates that ≡Fe(II) suspension is an cost-effective option for remediating Ni(II)-containing wastewater.

RTP: One Effective Platform to Probe Reactive Compound Transformation Products and Its Applications for a Reactive Plasticizer BADGE

Reactive compounds, such as covalent toxicants/drugs, have their ubiquitous occurrences and are known to react with protein or DNA in human beings, but their reactions with endogenous metabolites are rarely understood. Currently, a viable platform is demanded for discovering their reaction products since their efficacy/toxicity may be altered after the reaction. We aim to develop a platform for identifying unknown abiotic or biotransformation products for these reactive compounds. Based on stable isotope-labeling (SIL) metabolomics, we have developed a novel and robust analytical platform, reactive compound transformation profiler (RTP), which can automatically analyze preannotated high-resolution mass spectrometry (LC-HRMS) data sets and uncover probable transformation products. Generally, RTP consists of four complementary steps: (1) selecting peak pairs of light and heavy-labeled products, (2) defining the "core structure mass" for possible reaction search, (3) constructing an endogenous metabolite reaction database, and (4) developing algorithms to propose the potential transformation products by searching against the database with a single-/multiple-site reaction. Its performance was validated using the reactive plasticizer bisphenol A diglycidyl ether (BADGE) in several sample matrices. This platform enabled the identification of novel transformation products while also demonstrating its capacity to filter out the false-positive signals and provide product annotation. The RTP is freely accessible at https://github.com/FangLabNTU/Reactive-Compound-Transformation-Profiler-RTP-.

A comprehensive review on the analytical method, occurrence, transformation and toxicity of a reactive pollutant: BADGE

Bisphenol A diglycidyl ether (BADGE)-based epoxy resin is one of the most widely used epoxy resins with an annual production amount of several million tons. Compared with all other legacy or emerging organic compounds, BADGE is special due to its toxicity and high reactivity in the environment. More and more studies are available on its analytical methods, occurrence, transformation and toxicity. Here, we provided a comprehensive review of the current BADGE-related studies, with focus on its production, application, available analytical methods, occurrences in the environment and human specimen, abiotic and biotic transformation, as well as the in vitro and in vivo toxicities. The available data show that BADGE and its derivatives are ubiquitous environmental chemicals and often well detected in human specimens. For their analysis, a water-free sample pretreatment should be considered to avoid hydrolysis. Additionally, their complex reactions with endogenous metabolites are areas of great interest. To date, the monitoring and further understanding of their transport and fate in the environment are still quite lacking, comparing with its analogues bisphenol A (BPA) and bisphenol S (BPS). In terms of toxicity, the summary of its current studies and Environmental Protection Agency (EPA) ToxCast toxicity database suggests BADGE might be an endocrine disruptor, though more detailed evidence is still needed to confirm this hypothesis in in vivo animal models. Future study of BADGE should focus on its metabolic transformation, reaction with protein and validation of its role as an endocrine disruptor. We believe that the elucidation of BADGEs can greatly enhance our understandings of those reactive compounds in the environment and human.

Dissolution magnitude and kinetics of ZnO nanoparticles mediated by water are dependent on O vacancy abundance: The environmental implications

Metal oxide nanoparticles (NPs) dissolution in water environment is an important issue with regard to their environmental behaviors. The metal ion dissolves from surface defective site, but the effect of defect abundance remains largely unknown. This study aims to reveal this effect using ZnO NPs and O vacancy as the model system. The abundance of O vacancy is modulated by using different precursors and changing calcination atmosphere and temperature. X-ray photoelectron spectroscopy characterization shows that surface O vacancy abundance is effectively modulated to be distributed in a wide range from 15.3% to 41.8%. The deviation of O/Zn mole-ratio from 1.00 is used to denote O vacancy abundance in the bulk crystal, and the deviation reaches up to 0.32. Experiments show that the kinetics and magnitude of ZnO NPs dissolution vary in H₂O, which are highly dependent on O vacancy abundance. In comparison, the specific surface area and aggregation state take minor roles. Particularly, Zn²⁺ dissolution rate in the first hour is more linearly correlated with surface O vacancy abundance than with specific surface area. Defects and their abundances should thus be co-considered with other physicochemical properties to fully understand the dissolution behaviors of metal oxide NPs in water environment. This study is of significance in comprehensively assessing and predicting the environmental risk of metal oxide NPs.

A systematic assessment of aeration rate effect on aerobic degradation of municipal solid waste based on leachate chemical oxygen demand removal

Aeration is one mainstream technique to accelerate municipal solid waste (MSW) degradation in landfills. The determination of an appropriate aeration rate is critical to the design and operation of a landfill aeration system. In this study, we analyze 132 waste degradation tests reported in forty one studies in the literature. We use L min^-1 kg^-1 dry organic matter (L min^-1 kg^-1 DOM) as the uniform unit to quantify the aeration rates in all tests. The first order rate coefficient for chemical oxygen demand (COD) removal in leachate (k_COD) is selected as the parameter to characterize MSW degradation process. We further divide aerobic tests into five aerobic groups base on the respective aeration rates, i.e., <0.02, 0.02-0.1, 0.1-0.3, 0.3-1, and >1 L min^-1 kg^-1 DOM. With an increase in the aeration rate, the k_COD increases first and then decreases. The aeration rate between 0.1 and 0.3 L min^-1 kg^-1 DOM has the best enhancement on the k_COD. The k_COD values are not much higher than the anaerobic and semi-aerobic tests when the aeration rates are <0.1 L min^-1 kg^-1 DOM, because such aeration rates may be lower than the actual oxygen consumption rates. An aeration rate >0.3 L min^-1 kg^-1 DOM reduces the k_COD likely due to excess water evaporation and ventilation cooling. Among the analyzed results, the aeration rate is the most related to the k_COD in principal component analysis than the other factors, including liquid recirculation and addition, waste total density, waste degradation level, and waste initial temperature.

Hsa-miR-10a-5p promotes pancreatic cancer growth by BDNF/SEMA4C pathway

This article aims to explore the expression and mechanism of miR-10a-5p in pancreatic cancer. MiR-10a-5p mimic, MiR-10a-5p inhibitor and negative control were transfected into human pancreatic cancer cell line SW1990. Real-time quantitative PCR technology was used to analyze the expression level of miR-10a-5p in pancreatic cancer tissues and cells. The proliferation, invasion and apoptosis of SW1990 cells in each group were detected by CCK-8 analysis, Transwell analysis, TUNEL method and flow cytometry. Targetscan7.2 was used to predict the target protein of MiR-10a-5p, and the expression of related proteins was detected by Western blot analysis. The results showed that the expression of miR- 10a-5p in cancer tissues of patients with pancreatic cancer was significantly higher than that in adjacent tissues (P <0.05). The expression of miR-10a-5p in cancer cells increased significantly, which could promote the proliferation and invasion of SW1990 cells and inhibit apoptosis (P <0.05). Overexpression of miR-10a-5p can regulate the expression of BDNF and SEMA4C. miR-10a-5p can promote the occurrence and development of pancreatic cancer by regulating the BDNF / SEMA4C pathway, and may become a molecular target for the diagnosis and treatment of pancreatic cancer in the future.

Scaling up laboratory column testing results to predict coupled methane generation and biological settlement in full-scale municipal solid waste landfills

Prediction of methane (CH₄) generation and settlement of biodegrading municipal solid waste (MSW) is of primary interest to landfills aiming at biogas recovery for energy generation and MSW stabilization. We investigate these two concurring processes using datasets from 35 laboratory column tests and 8 pilot- and full-scale landfill cells available in the literature. We fit the datasets using three CH₄ generation models, i.e., conventional first-order decay (FOD) model, coupled FOD model, and coupled Gompertz model. The latter two models are proposed in this study which couple CH₄ generation with biological settlement strain (ε_B) instead of elapsed time. Each model requires only four to five input parameters which can be reasonably estimated a priori based on the initial conditions of the MSW and landfills. The performances of the models are compared using jackknife resampling approach and normalized root-mean-square error (NRMSE) values. The coupled Gompertz model results in on average 50% lower NRMSE when predicting the time-dependent CH₄ generation in all the datasets compared to the other two models. Thus, we demonstrate that CH₄ generation from biodegrading MSW in landfills can be better predicted using the corresponding ε_B than the elapsed time.

Use mechanochemical activation to enhance interfacial contaminant removal: A review of recent developments and mainstream techniques

Interfacial processes, including adsorption and catalysis, play crucial roles in environmental contaminant removal. Mechanochemical activation (MCA) emerges as a competitive method to improve the performance of adsorbents and catalysts. The development and application of MCA in the last decades are thereby systematically reviewed, particularly highlighting its contribution to interfacial process modulation. Two typical apparatuses for MCA are ball milling (BaM) and bead milling (BeM). Compared to BaM, BeM is able to yield a much higher MCA intensity, because it could pulverize bulk solid particles to nearly 100 nm. Since MCA intensity on the adsorbents and catalysts is directly responsible for the contaminant removal afterwards, quantitative and qualitative determination methods for valid MCA intensity are introduced. MCA benefits both the adsorption kinetics and capacity of powdered activated carbon by increasing the specific surface area. Carbon oxidation should be given an additional attention, but potentially favors the adsorption of heavy metals. MCA favors the catalyst performance by providing abundant surface functional group and increasing the free energy in the near-surface region. Finally, the future research needs are identified.

[Update in immune regulatory dysfunction of dendritic cells in sepsis]

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Further development of sepsis usually leads to septic shock or even death. Many previous studies have focused on the abnormal reactions of monocytes/macrophages, neutrophils, complement system, or cytokine inflammation in sepsis. Many evidences in recent years suggest that dendritic cells, as the most powerful antigen-presenting cells in innate immune system of body, play important role during the process of immune disorders of sepsis. In this article, I review the main classification, immune function, monitoring method, regulatory pathways of dendritic cells and their clinical significance in immune disorders of sepsis, so as to find new strategies for immune regulation of sepsis.

High-temperature annealing of ZnO nanoparticles increases the dissolution magnitude and rate in water by altering O vacancy distribution

The effects and mechanism of high-temperature annealing, a frequently-used strategy to modulate the properties of nanoparticles (NPs), on the dissolution of zinc oxide (ZnO) NPs are investigated in this study. The results show that annealing increases the ZnO NPs dissolution magnitude via increasing O vacancy abundance on the surface and in the bulk crystal. The face-dependent distribution of O vacancy is revealed by characterizing ZnO single crystal, and the (000-1) face has a higher abundance than the (10-10) face. Particularly, O vacancy abundance in the bulk (000-1) is about 3 times higher than in the bulk (10-10). Annealing further strengthens the face-dependence of O vacancy distribution, therefore both raw and annealed (000-1) faces contribute dominantly to the dissolution of ZnO NPs. Typical topographies of the surface defect sites on the (000-1) face and their evolutions during dissolution are collected. Annealing promotes the formation of larger and deeper etching pits. Elevated solution temperature and annealing synergize to further accelerate ZnO dissolution. The dissolution behaviors of ZnO NPs with different annealing statuses, surface properties, and solution temperatures investigated in this study have potential implications to the evaluations of environmental fate and risk of metal oxide NPs.

The relationship between plasma homocysteine levels and MTHFR gene variation, age, and sex in Northeast China

Background

Hyperhomocysteinemia (HHcy) is the risk factor for cardiovascular disease and stroke. However, the impacts on the genetic variation of methylene tetrahydrofolate reductase (MTHFR) on plasma homocysteine levels in the Northeast Chinese population have not been studied. Therefore, this study was carried out to determine the relationship between HHcy and MTHFR gene variation, and whether it was influenced by age and sex of the population in Northeast China.

Materials and Methods

A total of 466 subjects were randomly enrolled in this study. According to the homocysteine levels (Hcy ≥ 15 μmol/L) of the subjects, they were divided into hyperhomocysteine (HHcy = 206) and normal homocysteine (Hcy = 260). Polymerase chain reaction/high-resolution dissolution curve and homocysteine determination kit methods were used for genotype testing and homocysteine detection, respectively.

Results

High plasma homocysteine levels are associated with MTHFR 677T and 1298A [P < 0.00, odds ratio (confidence interval) = 1.842 (1.418-2.394) >1], which is related to increasing age (P_range = 0.0005-0.0161), with the homocysteine levels of males higher than females (P < 0.0001).

Conclusion

High plasma homocysteine levels were linked to the MTHFR gene mutation. In addition, plasma homocysteine levels increased significantly with age with male's homocysteine levels higher than that of females.

A thiocyanopalladation/carbocyclization transformation identified through enzymatic screening: stereocontrolled tandem C-SCN and C-C bond formation

Herein we describe a formal thiocyanopalladation/carbocyclization transformation and its parametrization and optimization using a new elevated temperature plate-based version of our visual colorimetric enzymatic screening method for reaction discovery. The carbocyclization step leads to C-SCN bond formation in tandem with C-C bond construction and is highly stereoselective, showing nearly absolute 1,2-anti-stereoinduction (5 examples) for substrates bearing allylic substitution, and nearly absolute 1,3-syn-stereoinduction (16 examples) for substrates bearing propargylic substitution. Based upon these high levels of stereoinduction, the dependence of the 1,2-stereoinduction upon cyclization substrate geometry, and the generally high preference for the transoid vinyl thiocyanate alkene geometry, a mechanistic model is proposed, involving (i) Pd(ii)-enyne coordination, (ii) thiocyanopalladation, (iii) migratory insertion and (iv) β-elimination. Examples of transition metal-mediated C-SCN bond formation that proceed smoothly on unactivated substrates and allow for preservation of the SCN moiety are lacking. Yet, the thiocyanate functionality is of great value for biophysical chemistry (vibrational Stark effect) and medicinal chemistry (S,N-heterocycle construction). The title transformation accommodates C-, O-, N- and S-bridged substrates (6 examples), thereby providing the corresponding carbocyclic or heterocyclic scaffolds. The reaction is also shown to be compatible with a significant range of substituents, varying in steric and electronic demand, including a wide range of substituted aromatics, fused bicyclic and heterocyclic systems, and even biaryl systems. Combination of this new transformation with asymmetric allylation and Grubbs ring-closing metathesis provides for a streamlined enantio- and diastereoselective entry into the oxabicyclo[3.2.1]octyl core of the natural products massarilactone and annuionone A, as also evidenced by low temperature X-ray crystal structure determination. Utilizing this bicyclic scaffold, we demonstrate the versatility of the thiocyanate moiety for structural diversification post-cyclization. Thus, the bridging vinyl thiocyanate moiety is smoothly elaborated into a range of derivative functionalities utilizing transformations that cleave the S-CN bond, add the elements of RS-CN across a π-system and exploit the SCN moiety as a cycloaddition partner (7 diverse examples). Among the new functionalities thereby generated are thiotetrazole and sulfonyl tetrazole heterocycles that serve as carboxylate and phosphate surrogates, respectively, highlighting the potential of this approach for future applications in medicinal chemistry or chemical biology.

Constant load and constant volume response of municipal solid waste in simple shear

Constant load and constant volume simple shear testing was conducted on relatively fresh municipal solid waste (MSW) from two landfills in the United States, one in Michigan and a second in Texas, at respective natural moisture content below field capacity. The results were assessed in terms of two failure strain criteria, at 10% and 30% shear strain, and two interpretations of effective friction angle. Overall, friction angle obtained assuming that the failure plane is horizontal and at 10% shear strain resulted in a conservative estimation of shear strength of MSW. Comparisons between constant volume and constant load simple shear testing results indicated significant differences in the shear response of MSW with the shear resistance in constant volume being lower than the shear resistance in constant load. The majority of specimens were nearly uncompacted during specimen preparation to reproduce the state of MSW in bioreactor landfills or in uncontrolled waste dumps. The specimens had identical percentage of <20mm material but the type of <20mm material was different. The <20mm fraction from Texas was finer and of high plasticity. MSW from Texas was overall weaker in both constant load and constant volume conditions compared to Michigan waste. The results of these tests suggest the possibility of significantly lower shear strength of MSW in bioreactor landfills where waste is placed with low compaction effort and constant volume, i.e., "undrained", conditions may occur. Compacted MSW specimens resulted in shear strength parameters that are higher than uncompacted specimens and closer to values reported in the literature. However, the normalized undrained shear strength in simple shear for uncompacted and compacted MSW was still higher than the normalized undrained shear strength reported in the literature for clayey and silty soils.

Quantification of parameters influencing methane generation due to biodegradation of municipal solid waste in landfills and laboratory experiments

The energy conversion potential of municipal solid waste (MSW) disposed of in landfills remains largely untapped because of the slow and variable rate of biogas generation, delayed and inefficient biogas collection, leakage of biogas, and landfill practices and infrastructure that are not geared toward energy recovery. A database consisting of methane (CH4) generation data, the major constituent of biogas, from 49 laboratory experiments and field monitoring data from 57 landfills was developed. Three CH4 generation parameters, i.e., waste decay rate (k), CH4 generation potential (L0), and time until maximum CH4 generation rate (tmax), were calculated for each dataset using U.S. EPA's Landfill Gas Emission Model (LandGEM). Factors influencing the derived parameters in laboratory experiments and landfills were investigated using multi-linear regression analysis. Total weight of waste (W) was correlated with biodegradation conditions through a ranked classification scheme. k increased with increasing percentage of readily biodegradable waste (Br0 (%)) and waste temperature, and reduced with increasing W, an indicator of less favorable biodegradation conditions. The values of k obtained in the laboratory were commonly significantly higher than those in landfills and those recommended by LandGEM. The mean value of L0 was 98 and 88L CH4/kg waste for laboratory and field studies, respectively, but was significantly affected by waste composition with ranges from 10 to 300L CH4/kg. tmax increased with increasing percentage of biodegradable waste (B0) and W. The values of tmax in landfills were higher than those in laboratory experiments or those based on LandGEM's recommended parameters. Enhancing biodegradation conditions in landfill cells has a greater impact on improving k and tmax than increasing B0. Optimizing the B0 and Br0 values of landfilled waste increases L0 and reduces tmax.

Abstract P3-01-13: Risk factors of non-sentinel lymph node metastasis in breast cancer patients with metastatic sentinel lymph node

Objective To study the factors influencing the non-sentinel lymph node(NSLN) status and to assess Memorial Sloan-Kettering Cancer Center (MSKCC) nomogram performance in predicting SLN metastases in a sentinel lymph node(SLN) positive Chinese breast cancer population. Methods Data were collected from breast cancer patients who were diagnosed with pathological positive sentinel lymph node and received further axillary lymph node dissection(ALND) in Shanghai Ruijin Hospital from January 2011 to August 2014. Use MSKCC nomogram to calculate each patient's NSLN metastasis risk score. The receiver operator characteristic curve(ROC curve)and the area under the ROC curve(AUC)was used to assess the predictive accuracy of the model. Results Among the 1147 patients who received sentinel biopsy in our center, 150 SLN positive patients who received ALND were enrolled in this study. By univariate analysis, multifocal breast cancer (P = 0.017), SLN+/SLN ratio (P = 0.010) and axillary lymphadenopathy displayed by ultrasound(P = 0.005) are the influencing factors of NSLN metastases. By multivariate analysis, multifocal breast cancer (OR 7.25, 95% CI 1.73∼30.43, P = 0.007), SLN+/SLN ratio≥0.5 (OR 2.564, 95% CI 1.22∼5.39, P = 0.013) and axillary lymphadenopathy displayed by ultrasound (OR 2.471, 95% CI 1.18∼5.19, P = 0.017) are the independent influencing factors of NSLN metastases. The AUC of MSKCC nomogram in this population is 0.677. Conclusion For breast cancer patients with positive sentinel lymph node, multifocality, SLN+/SLN ratio and axillary lymphadenopathy displayed by ultrasound is related to NSLN metastasis. MSKCC has low accuracy in predicting NSLN status of this population.

Citation Format: Huang J, Chen X, Shen K, Li Y, Chen W, He J, Zhu L, Huang O, Zong Y, Fei X, Jin X. Risk factors of non-sentinel lymph node metastasis in breast cancer patients with metastatic sentinel lymph node. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-01-13.

The role of middle calyx puncture in percutaneous nephrolithotomy: relative factors and choice considerations

Percutaneous nephrolithotomy (PCNL) is a well established procedure for management of renal calculi. It is generally believed that the access to the renal pelvic system via the desired calyx is the most crucial step during the whole procedure. The adequacy of the access directly influences the success and complication rates of PCNL. Traditionally, a lower pole access was routinely performed for less complication. Upper calices are also preferred for access in a given condition with large and complex calculi. However, the middle calices access is seldom selected. In aim to provide the reader some advantages of middle pole approach and a broaden horizon in determining the strategy of renal puncture, the present review describes the anatomical basis of the percutaneous tract. It provides a literature review of the success rate and efficiency of middle calyx access alone with the advantage of this approach, especially in dealing with large and complex stones.

Archaeal community structure in leachate and solid waste is correlated to methane generation and volume reduction during biodegradation of municipal solid waste

Duplicate carefully-characterized municipal solid waste (MSW) specimens were reconstituted with waste constituents obtained from a MSW landfill and biodegraded in large-scale landfill simulators for about a year. Repeatability and relationships between changes in physical, chemical, and microbial characteristics taking place during the biodegradation process were evaluated. Parameters such as rate of change of soluble chemical oxygen demand in the leachate (rsCOD), rate of methane generation (rCH4), rate of specimen volume reduction (rVt), DNA concentration in the leachate, and archaeal community structures in the leachate and solid waste were monitored during operation. The DNA concentration in the leachate was correlated to rCH4 and rVt. The rCH4 was related to rsCOD and rVt when waste biodegradation was intensive. The structures of archaeal communities in the leachate and solid waste of both simulators were very similar and Methanobacteriaceae were the dominant archaeal family throughout the testing period. Monitoring the chemical and microbial characteristics of the leachate was informative of the biodegradation process and volume reduction in the simulators, suggesting that leachate monitoring could be informative of the extent of biodegradation in a full-scale landfill.

Abstract P6-06-57: Progesterone receptor status and Ki-67 index may predict early relapse in luminal B/HER2 negative breast cancer patients

Purpose

Few studies has documented early relapse in luminalB/HER2-negative breast cancer. We examined prognostic factors for early relapse among these patients to improve treatment decision-making.

Patients and Methods

A total 398 patients with luminalB/HER2-negative breast cancer were included. Kaplan-Meier curves were applied to estimate disease-free survival (DFS) and Cox regression to identify prognostic factors.

Results

Absence of progesterone receptor (PR) expression was associated with higher tumor grade (p&lt; .001) and Ki-67 index (p = .010). PR-absent patients received more chemotherapy than the PR-present group (p = .009). After a median follow-up of 2 years, 17 patients (4.3%) had early relapses and 6 patients (1.5%) had died. The 2-year disease-free survival (DFS) was 97.2% in the PR-present and 88.6% in the PR-absent groups (Log-rank p = .004). Also, patients with a high Ki-67 index (defined as &gt;30%) had a reduced DFS when compared with low Ki-67 index group (≤30%) (97.6% vs 91.3%, respectively, Log-rank p = .025). In multivariate analysis, PR absence was significantly associated with a reduced DFS (HR = 4.031, 95% CI 1.293-12.574, p = .016).

Conclusion

PR absence was a prognostic factor for early relapse in luminal B/HER2-negative breast cancer, while a high Ki-67 index suggested a higher risk of early relapse.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-57.

Valosin-containing protein regulates the proteasome-mediated degradation of DNA-PKcs in glioma cells

DNA-dependent protein kinase (DNA-PK) has an important role in the repair of DNA damage and regulates the radiation sensitivity of glioblastoma cells. The VCP (valosine-containing protein), a chaperone protein that regulates ubiquitin-dependent protein degradation, is phosphorylated by DNA-PK and recruited to DNA double-strand break sites to regulate DNA damage repair. However, it is not clear whether VCP is involved in DNA-PKcs (DNA-PK catalytic subunit) degradation or whether it regulates the radiosensitivity of glioblastoma. Our data demonstrated that DNA-PKcs was ubiquitinated and bound to VCP. VCP knockdown resulted in the accumulation of the DNA-PKcs protein in glioblastoma cells, and the proteasome inhibitor MG132 synergised this increase. As expected, this increase promoted the efficiency of DNA repair in several glioblastoma cell lines; in turn, this enhanced activity decreased the radiation sensitivity and prolonged the survival fraction of glioblastoma cells in vitro. Moreover, the VCP knockdown in glioblastoma cells reduced the survival time of the xenografted mice with radiation treatment relative to the control xenografted glioblastoma mice. In addition, the VCP protein was also downregulated in ∼25% of GBM tissues from patients (WHO, grade IV astrocytoma), and the VCP protein level was correlated with patient survival (R²=0.5222, P<0.05). These findings demonstrated that VCP regulates DNA-PKcs degradation and increases the sensitivity of GBM cells to radiation.

Family quality of life of Chinese families of children with intellectual disabilities

BACKGROUND

The concepts of quality of life and family quality of life (FQOL) are increasingly being studied in the field of intellectual disabilities (ID) in China as important frameworks for: (1) assessing families' need for supports and services; (2) guiding organisational and service delivery system changes; and (3) evaluating quality family outcomes. The present study focused on exploring the perceptions of Chinese families who have a child with an ID regarding FQOL as well as examining the factor structure of FQOL concept from Chinese families.

METHODS

The Chinese version of the Family Quality of Life Scale was used to survey Chinese families living in the urban and suburban areas of Beijing who have a child with ID. A total of 442 families participated in this study. Confirmatory factor analysis was used to test the factor structure of FQOL. Multivariate analysis was also used to examine group differences among families in terms of family demographic variables.

RESULTS

A five-factor structure of the FQOL construct was found in the Chinese sample, suggesting a similar factor structure found from US families in the literature. Different living conditions (e.g. housing and transportation) tended to affect significantly families' satisfaction ratings of their FQOL. It is also found that family income and severity of disability of the child are predictors of families' satisfaction ratings of FQOL.

CONCLUSION

The preliminary findings of this study suggest a cross-cultural factor structure comparability of FQOL between samples in the USA and China. Results call for further examination of the family-centred service and support as a mediator on the interactive relationship between family characteristics, family needs and FQOL outcomes.

Serine/threonine protein phosphatase 6 modulates the radiation sensitivity of glioblastoma

Increasing the sensitivity of glioblastoma cells to radiation is a promising approach to improve survival in patients with glioblastoma multiforme (GBM). This study aims to determine if serine/threonine phosphatase (protein phosphatase 6 (PP6)) is a molecular target for GBM radiosensitization treatment. The GBM orthotopic xenograft mice model was used in this study. Our data demonstrated that the protein level of PP6 catalytic subunit (PP6c) was upregulated in the GBM tissue from about 50% patients compared with the surrounding tissue or control tissue. Both the in vitro survival fraction of GBM cells and the patient survival time were highly correlated or inversely correlated with PP6c expression (R²=0.755 and −0.707, respectively). We also found that siRNA knockdown of PP6c reduced DNA-dependent protein kinase (DNA-PK) activity in three different GBM cell lines, increasing their sensitivity to radiation. In the orthotopic mice model, the overexpression of PP6c in GBM U87 cells attenuated the effect of radiation treatment, and reduced the survival time of mice compared with the control mice, while the PP6c knocking-down improved the effect of radiation treatment, and increased the survival time of mice. These findings demonstrate that PP6 regulates the sensitivity of GBM cells to radiation, and suggest small molecules disrupting or inhibiting PP6 association with DNA-PK is a potential radiosensitizer for GBM.