Improved uniform persistence for partially diffusive models of infectious diseases: cases of avian influenza and Ebola virus disease.

Past works on partially diffusive models of diseases typically rely on a strong assumption regarding the initial data of their infection-related compartments in order to demonstrate uniform persistence in the case that the basic reproduction number $ \mathcal{R}_0 $ is above 1. Such a model for avian influenza was proposed, and its uniform persistence was proven for the case $ \mathcal{R}_0 > 1 $ when all of the infected bird population, recovered bird population and virus concentration in water do not initially vanish. Similarly, a work regarding a model of the Ebola virus disease required that the infected human population does not initially vanish to show an analogous result.

Continuous nucleation of metallic nanoparticles photocatalytic reduction.

Whether in organic synthesis or solar energy conversion, light can be a powerful reagent in chemical reactions and introduce new opportunities for synthetic control including duration, intensity, interval, and energy of irradiation. Here, we report the use of a molecular photosensitizer as a reducing agent in metallic nanoparticle syntheses. Using this approach, we report three key findings.

Mechanisms of oxidative removal of 1,4-dioxane via free chlorine rapidly mixing into monochloramine: Implications on water treatment and reuse.

Free chlorine (HOCl) and monochloramine (NHCl) are two of the most commonly used water disinfectants in water treatment; however, the capability of rapid mixing of HOCl into NHCl to induce oxidative reactions for efficient removal of contaminants remains largely unknown. In this study, 1,4-dioxane (1,4-D) removal was quantified during the rapid mixing of HOCl into NHCl, to evaluate the effects of solution pH and HOCl-to-NHCl ratio, and to identify mechanisms by which reactive species are generated in the system. Results showed that the highest 1,4-D removal was observed at the near-neutral pH of 6 with the HOCl-to-NHCl molar ratio of 1.

Is "Response/No Response" Too Simple a Notion for RTI Frameworks? Exploring Multiple Response Types With Latent Profile Analysis.

We conducted a secondary analysis of data from a randomized control trial to explore this question: Does "response/no response" best characterize students' reactions to a generally efficacious first-grade reading program, or is a more nuanced characterization necessary? Data were collected on 265 at-risk readers' word reading prior to and immediately following program implementation in first grade and in spring of second grade. Pretreatment data were also obtained on domain-specific skills (letter knowledge, decoding, passage comprehension, language) and domain-general skills (working memory, non-verbal reasoning). Latent profile analysis of word reading across the three time points with controls as a local norm revealed a group ( = 45) with mean word-reading scores of 0.

Optimizing Potable Water Reuse Systems: Chloramines or Hydrogen Peroxide for UV-Based Advanced Oxidation Process?

The tapping of municipal wastewater for potable reuse significantly enhances drinking water supply in drought-stricken regions worldwide. Membrane-based potable reuse treatment trains commonly employ ultraviolet-based advanced oxidation processes (UV-AOPs) to degrade trace organic contaminants in water to produce high-quality recycled water. Hydrogen peroxide (HO) is used as the default photo-oxidant.

Degradation of nitrilotris-methylenephosphonic acid (NTMP) antiscalant via persulfate photolysis: Implications on desalination concentrate treatment.

Nitrilotris-methylenephosphonic acid (NTMP) has been widely used as an antiscalant in reverse osmosis (RO) desalination and other industrial processes to inhibit scaling from calcium and other hardness ions. Removal of NTMP from RO concentrate can induce the precipitation of oversaturated scale-forming substances, enable additional water recovery from RO concentrate, and reduce the risk of eutrophication after brine disposal. This study investigated the kinetics and mechanisms of oxidative degradation of NTMP by UV photolysis of persulfate at 254 nm.

Using Moderator Analysis to Identify the First-Grade Children Who Benefit More and Less from a Reading Comprehension Program: A Step Toward Aptitude-by-Treatment Interaction.

Because of the importance of teaching reading comprehension to struggling young readers and the infrequency with which it has been implemented and evaluated, we designed a comprehensive first-grade reading comprehension program. We conducted a component analysis of the program's decoding/fluency (DF) and reading comprehension (COMP) dimensions, creating DF and DF+COMP treatments to parse the value of COMP. Students ( = 125) were randomly assigned to the 2 active treatments and controls.

A Longitudinal Analysis of the Trajectories and Predictors of Word Reading and Reading Comprehension Development Among At-Risk Readers.

This study explored the developmental trajectories and predictors of word reading and reading comprehension among young at-risk readers. In fall of first grade, 185 students identified as at-risk for reading difficulties were assessed on measures of domain-specific skills (phonological awareness, letter knowledge, and vocabulary), domain-general skills (working memory, nonverbal reasoning, and processing speed), and word reading and reading comprehension. Word reading and reading comprehension were assessed again in spring of grades 1-4.

Photolysis of Mono- and Dichloramines in UV/Hydrogen Peroxide: Effects on 1,4-Dioxane Removal and Relevance in Water Reuse.

Growing demands and increasing scarcity of fresh water resources necessitate potable water reuse, which has been implemented with the aid of UV-based advanced oxidation processes (UV/AOPs) that remove potentially hazardous trace organic contaminants from reclaimed water. During the potable reuse treatment process, chloramines are added to prevent membrane fouling that are carried over to the UV/AOP, where hydrogen peroxide (HO) is commonly added. However, the impact of chloramines on the photolysis of HO and the overall performance of the UV/AOP remains unknown.

UV Photolysis of Chloramine and Persulfate for 1,4-Dioxane Removal in Reverse-Osmosis Permeate for Potable Water Reuse.

A sequential combination of membrane treatment and UV-based advanced oxidation processes (UV/AOP) has become the industry standard for potable water reuse. Chloramines are used as membrane antifouling agents and therefore carried over into the UV/AOP. In addition, persulfate (SO) is an emerging oxidant that can be added into a UV/AOP, thus creating radicals generated from both chloramines and persulfate for water treatment.

Bromide-assisted catalytic oxidation of lead(ii) solids by chlorine in drinking water distribution systems.

This study investigated the effect of bromide on the oxidation of three lead(ii) solids by chlorine - a redox process critical to the control of lead release in drinking water distribution systems. Bromide had a strong catalytic effect on the oxidation of lead(ii) carbonate solids, but had a limited impact on the oxidation of lead(ii) phosphate.

A longitudinal study on predictors of early calculation development among young children at risk for learning difficulties.

The purpose of this study was to explore domain-general cognitive skills, domain-specific academic skills, and demographic characteristics that are associated with calculation development from first grade to third grade among young children with learning difficulties. Participants were 176 children identified with reading and mathematics difficulties at the beginning of first grade. Data were collected on working memory, language, nonverbal reasoning, processing speed, decoding, numerical competence, incoming calculations, socioeconomic status, and gender at the beginning of first grade and on calculation performance at four time points: the beginning of first grade, the end of first grade, the end of second grade, and the end of third grade.

A Minimum Spanning Forest Based Hyperspectral Image Classification Method for Cancerous Tissue Detection.

Hyperspectral imaging is a developing modality for cancer detection. The rich information associated with hyperspectral images allow for the examination between cancerous and healthy tissue. This study focuses on a new method that incorporates support vector machines into a minimum spanning forest algorithm for differentiating cancerous tissue from normal tissue.

Behavioral Attention: A Longitudinal Study of Whether and How It Influences the Development of Word Reading and Reading Comprehension among At-Risk Readers.

The purpose of this study was to examine the extent to which teacher ratings of behavioral attention predicted responsiveness to word reading instruction in first grade and third-grade reading comprehension performance. Participants were 110 first grade students identified as at-risk for reading difficulties who received 20 weeks of intensive reading intervention in combination with classroom reading instruction. Path analysis indicated that teacher ratings of student attention significantly predicted students' word reading growth in first grade even when they were competed against other relevant predictors (phonological awareness, nonword reading, sight word efficiency, vocabulary, listening comprehension, hyperactivity, nonverbal reasoning, and short term memory).