Effect of Alkyl Chain Branching Point on 3D Crystallinity in High N‐Type Mobility Indolonaphthyridine Polymers

Herein, this study investigates the impact of branching‐point‐extended alkyl chains on the charge transport properties of three ultrahigh n‐type mobility conjugated polymers. Using grazing incidence wide‐angle X‐ray scattering, analysis of the crystallinity of the series shows that while π–π interactions are increased for all three polymers as expected, the impact of the side‐chain engineering on polymer backbone crystallinity is unique to each polymer and correlates to the observed changes in charge transport. With the three polymers exhibiting n‐type mobilities between 0.63 and 1.04 cm² V^?1 s^?1, these results ratify that the indolonaphthyridine building block has an unprecedented intrinsic ability to furnish high‐performance n‐type organic semiconductors.     

Recent Progress in High‐Mobility Organic Transistors: A Reality Check

Over the past three decades, significant research efforts have focused on improving the charge carrier mobility of organic thin‐film transistors (OTFTs). In recent years, a commonly observed nonlinearity in OTFT current–voltage characteristics, known as the “kink” or “double slope,” has led to widespread mobility overestimations, contaminating the relevant literature. Here, published data from the past 30 years is reviewed to uncover the extent of the field‐effect mobility hype and identify the progress that has actually been achieved in the field of OTFTs. Present carrier‐mobility‐related challenges are identified, finding that reliable hole and electron mobility values of 20 and 10 cm² V^?1 s^?1, respectively, have yet to be achieved. Based on the analysis, the literature is then reviewed to summarize the concepts behind the success of high‐performance p‐type polymers, along with the latest understanding of the design criteria that will enable further mobility enhancement in n‐type polymers and small molecules, and the reasons why high carrier mobility values have been consistently produced from small molecule/polymer blend semiconductors. Overall, this review brings together important information that aids reliable OTFT data analysis, while providing guidelines for the development of next‐generation organic semiconductors.     

Groundwater Protection,Risk Awareness,Knowledge Transfer and Public Health: The Role of “Future Custodians”

A survey of young adults was conducted at several 3rd level agricultural institutions across Ireland over a 6-month period. The results from the agri-student survey were compared and contrasted with those of an identical survey of private well owners. Students (n?=?246) scored significantly lower than well owners (n?=?245) in two developed metrics, namely “groundwater source awareness” and “groundwater contamination awareness” (p?n?=?476). Clusters comprised four predictors: presence of an elderly householder (predictor importance = 0.91), residence within the household during well design (predictor importance = 0.55), presence of an infant or young child (≤5 years) in the household (predictor importance = 0.48) previous instance of gastrointestinal illness or symptoms within the household (predictor importance = 0.31) The results of this research may be used to inform future risk management, communication and knowledge transfer policies, which are currently required to ensure the safeguarding of private groundwater supplies both in Ireland and further afield.     

Evaluation and critique of Healthcare Failure Mode and Effect Analysis applied in a radiotherapy case study

Healthcare Failure Mode and Effect Analysis (HFMEA®) has been developed to support the proactive analysis of health care treatment processes. Its use has been reported in several studies with both positive and negative comments regarding the quality of the results and the efficacy of the method. This paper examines the HFMEA® methodology and discusses the challenges that were encountered during its application to a proactive analysis of radiotherapy patient record systems in a large public hospital. Several weaknesses in the HFMEA® method and particularly in the HFMEA Decision Tree^TM are also discussed. Recommendations to support future HFMEA® studies and also for the re‐design of the HFMEA Decision Tree^TM to overcome the identified weaknesses are included. Based on these recommendations, a new decision tree is presented to guide future analyses. © 2012 Wiley Periodicals, Inc.     

Ingested engineered nanomaterials: state of science in nanotoxicity testing and future research needs

Background

Engineered nanomaterials (ENM) are used extensively in food products to fulfill a number of roles, including enhancement of color and texture, for nutritional fortification, enhanced bioavailability, improved barrier properties of packaging, and enhanced food preservation. Safety assessment of ingested engineered nanomaterials (iENM) has gained interest in the nanotoxicology community in recent years. A variety of test systems and approaches have been used for such evaluations, with in vitro monoculture cell models being the most common test systems, owing to their low cost and ease-of-use. The goal of this review is to systematically assess the current state of science in toxicological testing of iENM, with particular emphasis on model test systems, their physiological relevance, methodological strengths and challenges, realistic doses (ranges and rates), and then to identify future research needs and priorities based on these assessments.

Methods

Extensive searches were conducted in Google Scholar, PubMed and Web of Science to identify peer-reviewed literature on safety assessment of iENM over the last decade, using keywords such as “nanoparticle”, “food”, “toxicity”, and combinations thereof. Relevant literature was assessed based on a set of criteria that included the relevance of nanomaterials tested; ENM physicochemical and morphological characterization; dispersion and dosimetry in an in vitro system; dose ranges employed, the rationale and dose realism; dissolution behavior of iENM; endpoints tested, and the main findings of each study. Observations were entered into an excel spreadsheet, transferred to Origin, from where summary statistics were calculated to assess patterns, trends, and research gaps.

Results

A total of 650 peer-reviewed publications were identified from 2007 to 2017, of which 39 were deemed relevant. Only 21% of the studies used food grade nanomaterials for testing; adequate physicochemical and morphological characterization was performed in 53% of the studies. All in vitro studies lacked dosimetry and 60% of them did not provide a rationale for the doses tested and their relevance. Only 12% of the studies attempted to consider the dissolution kinetics of nanomaterials. Moreover, only 1 study attempted to prepare and characterize standardized nanoparticle dispersions.

Conclusion

We identified 5 clusters of factors deemed relevant to nanotoxicology of food-grade iENM: (i) using food-grade nanomaterials for toxicity testing; (ii) performing comprehensive physicochemical and morphological characterization of iENM in the dry state, (iii) establishing standard NP dispersions and their characterization in cell culture medium, (iv) employing realistic dose ranges and standardized in vitro dosimetry models, and (v) investigating dissolution kinetics and biotransformation behavior of iENM in synthetic media representative of the gastrointestinal (GI) tract fluids, including analyses in a fasted state and in the presence of a food matrix. We discussed how these factors, when not considered thoughtfully, could influence the results and generalizability of in vitro and in vivo testing. We conclude with a set of recommendations to guide future iENM toxicity studies and to develop/adopt more relevant in vitro model systems representative of in vivo animal and human iENM exposure scenarios.

     

Resident supervision in the operating room: does this impact on outcome?

Resident supervision by faculty is a sine qua non of surgical education, yet objective standards for supervision are difficult to quantify. Over a 12-month period, using departmental data on morbidity, mortality outcome, and faculty status in the operating room, the association between complications, death, and attending physician presence were analyzed by Chi-square tests of association in 2 x 2 contingency tables, or by the Mantel-Haenszel Chi-square to control for a stratifying variable. A total of 4417 cases were reported. Attending physicians were either scrubbed or present in the OR 91.8% of the time, although there was considerable variation among services. The overall mortality rate was 6.2% and complications occurred in 7.0% overall. Greater attending physician presence was significantly associated with lower mortality and complication rates overall. When stratified by service, the association was less marked. However, presence of attending physicians varied significantly by service. To adjust for this variation, elective services were compared with all the "nonelective" services. When this categorization was used as the stratifying variable, the association between increased attending physician involvement and decreased complication and mortality rates was statistically significant (Mantel-Haenszel Chi-square, p < 0.0005 for both).     

Further improvements to the Bauer-Millward attack on the Hill cipher

The Bauer-Millward attack on the Hill cipher seeks to recover the individual rows of the decryption matrix instead of the entire matrix. The authors present some improvements to the Bauer-Millward attack that reduce the computational workload by a factor of φ(L), where φ is the Euler totient function, and L is the length of the alphabet. They also present a method of efficiently combining the top rows to recover the decryption matrix. Performance statistics are provided for blocks up to size 5, and example analyses are given for blocks up to size 8. Previous authors have stopped at size 4.     

Alcohol use disorder history moderates the relationship between avoidance coping and posttraumatic stress symptoms.

Avoidance coping (AVC) is common in individuals with posttraumatic stress disorder (PTSD) and in individuals with alcohol use disorder (AUD). Given that PTSD and AUD commonly co-occur, AVC may represent a risk factor for the development of comorbid posttraumatic stress and alcohol use. In this study, the relationship between AVC and PTSD symptoms (PTSS) was examined in individuals with versus without AUDs. Motor vehicle accident (MVA) victims were assessed 6 weeks postaccident for AUD history (i.e. diagnoses of current or past alcohol abuse or dependence) and AVC. PTSS were assessed 6 weeks and 6 months post-MVA. All analyses were conducted on the full sample of MVA victims as well as on the subset of participants who were legally intoxicated (blood alcohol concentration ≥ 0.08) during the accident. It was hypothesized that the relationship between AVC and PTSS would be stronger in those individuals with an AUD history and especially strong in the subset of individuals who were legally intoxicated during the MVA. Results were largely supportive of this hypothesis, even after controlling for in-hospital PTSS, gender, and current major depression. Early assessment of AUD history and avoidance coping may aid in detecting those at elevated risk for PTSD, and intervening to reduce AVC soon after trauma may help buffer the development of PTSD + AUD comorbidity. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Comparison of Quercetin Pharmacokinetics Following Oral Supplementation in Humans

Abstract: The objective of the study was to investigate the absorption of quercetin aglycone in 18 healthy human subjects administered via the following oral carrier systems: suspension of quercetin (quercetin QU995 powder in Tang^® and spring water), nutritional bars (First Strike?), and chews (RealFX? Q‐Plus?). Subjects were divided into 3 groups of 6 individuals each receiving 500 mg quercetin in one of the aforementioned formulations. Blood levels were monitored immediately pre‐ and for 32 h postadministration. The concentration of total quercetin in blood samples was determined by solid phase extraction followed by high‐performance liquid chromatography analysis. Pharmacokinetic parameters were determined by noncompartmental modeling using Kinetica software. The C_max of quercetin was highest with RealFX? Q‐Plus? Chews (1051.9 ± 393.1 μg/L) achieved within 3.3 h as compared to that for First Strike? Bars (698.1 ± 189.5 μg/L in 2.3 h) and Tang^® suspension (354.4 ± 87.6 μg/L in 4.7 h). The results showed no statistically significant difference in quercetin absorption among groups due to high variability within groups receiving quercetin from same dosage form. This study represents the first comprehensive evaluation of quercetin absorption from quercetin fortified oral food products at doses commonly used for quercetin supplementation. Practical Application: The current study describes for the first time, comprehensive evaluation of quercetin PK in humans from quercetin fortified oral food products at doses commonly used for quercetin supplementation. Owing to quercetin's potent antioxidant and anti‐inflammatory actions, quercetin is widely being used as a nutritional supplement. In order to maximize the bioavailability of quercetin for its use in efficacy studies, it is important to determine its ideal oral carrier system and route for its delivery. The current research unveils vital information about quercetin supplementation to the international community, especially to soldiers, athletes, and the dietary supplement industry.     

Comparative Evaluation of Intestinal Nitric Oxide in Embryonic Zebrafish Exposed to Metal Oxide Nanoparticles

Nanoparticle (NP) exposure may induce oxidative stress through generation of reactive oxygen and nitrogen species, which can lead to cellular and tissue damage. The digestive system is one of the initial organs affected by NP exposure. Here, it is demonstrated that exposure to metal oxide NPs induces differential changes in zebrafish intestinal NO concentrations. Intestinal NO concentrations are quantified electrochemically with a carbon fiber microelectrode inserted in the intestine of live embryos. Specificity of the electrochemical signals is demonstrated by NO‐specific pharmacological manipulations and the results are correlated with the 4,5‐diaminofluorescein‐diacetate (DAF‐FM‐DA). NPs are demonstrated to either induce or reduce physiological NO levels depending on their redox reactivity, type and dose. NO level is altered following exposure of zebrafish embryos to CuO and CeO₂ NPs at various stages and concentrations. CuO NPs increase NO concentration, suggesting an intestinal oxidative damage. In contrast, low CeO₂ NP concentration exposure significantly reduces NO levels, suggesting NO scavenging activity. However, high concentration exposure results in increased NO. Alterations in NO concentration suggest changes in intestinal physiology and oxidative stress, which will ultimately correspond to NPs toxicity. This work also demonstrates the use of electrochemistry to monitor in vivo changes of NO within zebrafish organs.