Environmental impacts of alternative cement binders.

Cement production is among the most difficult industrial activities to decarbonize. Various measures have been proposed and explored to reduce its CO2 emissions. Among these measures, the substitution of portland cement (PC) clinker with alternative materials is arguably the most effective, and consequently is an area of high research and commercial interest. However, few studies have systematically quantified environmental impacts of alternative, i.e., non-PC, clinkers. Here, we quantify and compare environmental impacts arising from the production of binders derived from several of the most commonly investigated alternative cement systems. We show that binders derived from most of these alternative cements result in lower greenhouse gas (GHG) emissions as well as other indicators of environmental impacts relative to the PC binder. The extent of these reductions varies as a function of energy requirements for production, process-related emissions from clinker formation, and raw materials demand. While utilization of alternative cements can be environmentally beneficial, similar reductions in GHG emissions can be achieved through use of partial replacement of PC with mineral admixtures. In this work, we quantitatively demonstrate the potential for alternative binders to mitigate environmental burdens and highlight the need to consider trade-offs among environmental impact categories when assessing these products

Master\u27s Recital

List of performers and performances

Transport fluctuations in integrable models out of equilibrium

We propose exact results for the full counting statistics, or the scaled cumulant generating function, pertaining to the transfer of arbitrary conserved quantities across an interface in homogeneous integrable models out of equilibrium. We do this by combining insights from generalised hydrodynamics with a theory of large deviations in ballistic transport. The results are applicable to a wide variety of physical systems, including the Lieb-Liniger gas and the Heisenberg chain. We confirm the predictions in non-equilibrium steady states obtained by the partitioning protocol, by comparing with Monte Carlo simulations of this protocol in the classical hard rod gas. We verify numerically that the exact results obey the correct non-equilibrium fluctuation relations with the appropriate initial conditions.Comment: v1: 7 + 8 pages, 6 figures. v2: 32 pages, format and discussion improved. v3: typo in the formula for c4 corrected. v4: 33 pages, discussion further improve

Chromatin accessibility dynamics of Chlamydia-infected epithelial cells.

Chlamydia are Gram-negative, obligate intracellular bacterial pathogens responsible for a broad spectrum of human and animal diseases. In humans, Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection worldwide and is the causative agent of trachoma (infectious blindness) in disadvantaged populations. Over the course of its developmental cycle, Chlamydia extensively remodels its intracellular niche and parasitises the host cell for nutrients, with substantial resulting changes to the host cell transcriptome and proteome. However, little information is available on the impact of chlamydial infection on the host cell epigenome and global gene regulation. Regions of open eukaryotic chromatin correspond to nucleosome-depleted regions, which in turn are associated with regulatory functions and transcription factor binding. We applied formaldehyde-assisted isolation of regulatory elements enrichment followed by sequencing (FAIRE-Seq) to generate temporal chromatin maps of C. trachomatis-infected human epithelial cells in vitro over the chlamydial developmental cycle. We detected both conserved and distinct temporal changes to genome-wide chromatin accessibility associated with C. trachomatis infection. The observed differentially accessible chromatin regions include temporally-enriched sets of transcription factors, which may help shape the host cell response to infection. These regions and motifs were linked to genomic features and genes associated with immune responses, re-direction of host cell nutrients, intracellular signalling, cell-cell adhesion, extracellular matrix, metabolism and apoptosis. This work provides another perspective to the complex response to chlamydial infection, and will inform further studies of transcriptional regulation and the epigenome in Chlamydia-infected human cells and tissues

Permeability is the critical factor governing the life cycle environmental performance of drinking water treatment using living filtration membranes.

Living Filtration Membranes (LFMs) are a water filtration technology that was recently developed in the lab (Technology Readiness Level 4). LFMs have shown filtration performance comparable with that of ultrafiltration, far better fouling resistance than conventional polymer membranes, and good healing capabilities. These properties give LFMs promise to address two significant issues in conventional membrane filtration: fouling and membrane damage. To integrate environmental considerations into future technology development (i.e., Ecodesign), this study assesses the life cycle environmental performance of drinking water treatment using LFMs under likely design and operation conditions. It also quantitatively ranks the engineering design and operation factors governing the further optimization of LFM environmental performance using a global sensitivity analysis. The results suggest that LFMs' superior fouling resistance will reduce the life cycle environmental impacts of ultrafiltration by 25% compared to those of a conventional polymer membrane in most impact categories (e.g., acidification, global warming potential, and carcinogenics). The only exception is the eutrophication impact, where the need for growth medium and membrane regeneration offsets the benefits of LFMs' fouling resistance. Permeability is the most important factor that should be prioritized in future R&D to further improve the life cycle environmental performance of LFMs. A 1% improvement in the permeability will lead to a ∼0.7% improvement in LFMs' environmental performance in all the impact categories, whereas the same change in the other parameters investigated (e.g., LFM lifespan and regeneration frequency) typically only leads to a <0.2% improvement

Evaluating narrative operative reports for endoscopic sinus surgery in a residency training program

Objective: The narrative operative report (NR) bears testimony to critical elements of patient care. Residents' NRs also provide insights into their comprehension of the procedure. NR documentation is an informal element of surgical residency training but data regarding quality of such training are scant. We aim to evaluate the NR within a residency training program. Methods: The quality of NRs for endoscopic sinus surgery (ESS) was evaluated through a retrospective analysis of 90 NRs for ESS. Thirty-four elements that the attending surgeon regards as "critical" variables, or quality indicators (QIs), that should be documented, were studied to evaluate quality. A "performance metric (PM)," defined as the average percent of QIs dictated/total word count, was determined. Subgroup analysis by the level of training was additionally performed. Results: Surgical indications, procedural steps, and immediate postoperative findings were accurately documented in 71%, 84%, and 82% of patients, respectively. The attending surgeon had the highest proportion of included key elements (89% +/- 6.2%) followed by junior residents (87% +/- 5.7%) and then senior residents (80% +/- 14%) (P = .008). The attending surgeon also demonstrated the highest PM, followed by senior and then junior residents (P < .0001). Conclusions: The quality of NRs was found to be high overall, but not "perfect" for either the attending or trainee surgeon. The PM among residents was expectedly lower than the attending surgeon. We propose that a synoptic reporting system that ensures inclusion of key elements may be helpful in training residents (and attendings) in creating comprehensive and efficient NRs. Level of Evidence: 3Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

A roadmap for production of cement and concrete with low-CO2 emissions

This review will show that low-CO2 cements can be produced to give superior durability, based on a sound understanding of their microstructure and how it impacts macro-engineering properties. For example, it is essential that aluminium is available in calcium-rich alkali-activated systems to offset the depolymerisation effect of alkali cations on C-(N-)A-S-H gel. The upper limit on alkali cation incorporation into a gel greatly affects mix design and source material selection. A high substitution of cement clinker in low-CO2 cements may result in a reduction of pH buffering capacity, hence susceptibility to carbonation and corrosion of steel reinforcement. With careful mix design, a more refined pore structure and associated lower permeability can still give a highly durable concrete. It is essential to expand thermodynamic databases for current and prospective cementitious materials so that concrete performance and durability can be predicted when using low-CO2 binders. Cationic copolymer and amphoteric plasticisers, when available commercially, will enhance the development of alkali-activated materials. The development of supersonic shockwave reactors will enable the conversion of a wide range of virgin and secondary source materials into cementitious materials, replacing blast furnace slag and coal fly ash that have dwindling supply. A major obstacle to the commercial adoption of low-CO2 concrete is the prescriptive nature of existing standards and design codes, so there is an urgent need to shift towards performance-based standards. The roadmap presented here is not an extension of current cement practice, but a new way of integrating fundamental research, equipment innovation, and commercial opportunity

Study of Foaming Properties and Effect of the Isomeric Distribution of Some Anionic Surfactants

Using different reaction conditions of photosulfochlorination of n-dodecane, two samples of anionic surfactants of sulfonate type are obtained. Their micellar behavior has been already reported and the relationship between their isomeric distribution and their chemical structures and micellar behaviors have been more thoroughly explored. In this investigation, we screened the foaming properties (foaming power and foam stability) by a standardized method very similar to the Ross–Miles foaming tests to identify which surfactants are suitable for applications requiring high foaming, or, alternatively, low foaming. The results obtained for the synthesized surfactants are compared to those obtained for an industrial sample of secondary alkanesulfonate (Hostapur 60) and to those of a commercial sample of sodium dodecylsulfate used as reference for anionic surfactants. The foam formation and foam stability of aqueous solutions of the two samples of dodecanesulfonate are compared as a function of their isomeric distribution. These compounds show good foaming power characterized in most cases by metastable or dry foams. The highest foaming power is obtained for the sample rich in primary isomers which also produces foam with a relatively high stability. For the sample rich in secondary isomers we observe under fixed conditions a comparable initial foam height but the foam stability turns out to be low. This property is interesting for applications requiring low foaming properties such as dishwashing liquid for machines. The best results are observed near and above the critical micellar concentrations and at 25 C for both the samples

The Law and Policy of Child Maltreatment

Each year in the United States some four million children are reported to child protective services and hundreds of thousands of children are confirmed victims of maltreatment. This chapter provides a brief overview of the civil and criminal law’s response to child abuse and neglect. It summarizes the major federal statutes that provide funding to the states to support both civil and criminal law responses to maltreatment. It discusses the division of responsible for responding to child maltreatment between the federal and state governments (federalism). It also provides a summary of the constitutional framework for handling both civil and criminal child maltreatment cases