Experimental and Theoretical Studies of the Environmental Sensitivity of the Absorption Spectra and Photochemistry of Nitenpyram and Analogs

Neonicotinoid (NN) pesticides have widespread use, largely replacing other pesticides such as the carbamates. Hence, there is a need to understand their environmental fates at a molecular level in various media, especially water. We report here the studies of a nitroenamine NN, nitenpyram (NPM), in aqueous solution where the absorption cross sections in the actinic region above 290 nm are observed to dramatically decrease compared to those in nonaqueous solvents. Quantum chemical calculations show that addition of a proton to the tertiary amine nitrogen in NPM breaks the conjugation in the chromophore, shifting the absorption to shorter wavelengths, consistent with experiment. However, surprisingly, adding a proton to the secondary amine nitrogen leads to its immediate transfer to the NO2 group, preserving the conjugation. This explains why the UV absorption of ranitidine (RAN), which has a similar chromophore but only secondary amine nitrogens, does not show a similar large blue shift in water. Photolysis quantum yields in aqueous NPM solutions were measured to be φ = 0.18 ± 0.07 at 254 nm, (9.4 ± 1.6) × 10-2 with broadband radiation centered at 313 nm and (5.2 ± 1.1) × 10-2 for broadband radiation centered at 350 nm (errors are 2σ). The major products in aqueous solutions are an imine that was also formed in the photolysis of the solid and a carboxylic acid derivative that is unique to the photolysis in water. Combining the larger quantum yields in water with the reduced absorption cross sections results in a calculated lifetime of NPM of only 5 min at a solar zenith angle of 35°, typical of 40°N latitude on April 1. The products do not absorb in the actinic region and hence will be long-lived with respect to photolysis

Structure determination of disordered metallic sub-monolayers by helium scattering: a theoretical and experimental study

An approach based on He scattering is used to develop an atomic-level structural model for an epitaxially grown disordered sub-monolayer of Ag on Pt(111) at 38 K. Quantum scattering calculations are used to fit structural models to the measured angular intensity distribution of He atoms scattered from this system. The structure obtained corresponds to narrowly size-dispersed compact clusters with a modest translational disorder, and not to fractals, which might be expected due to the low surface temperature. The clusters are up to two layers in height, the lower one having only a few defects. The relations between specific features of the angular scattering distribution, and properties such as the cluster sizes and shapes, the inter-cluster distance distribution, etc. are discussed. The results demonstrate the usefulness of He scattering as a tool for unraveling new complex surface phases. © 1998 Elsevier Science B.V. All rights reserved

First Evidence for Adoption in California Sea Lions

Demographic parameters such as birth and death rates determine the persistence of populations. Understanding the mechanisms that influence these rates is essential to developing effective management strategies. Alloparental behavior, or the care of non-filial young, has been documented in many species and has been shown to influence offspring survival. However, the role of alloparental behavior in maintaining population viability has not been previously studied. Here, we provide the first evidence for adoption in California sea lions and show that adoption potentially works to maintain a high survival rate of young and may ultimately contribute to population persistence. Alloparental behavior should have a positive effect on the population growth rate when the sum of the effects on fitness for the alloparent and beneficiary is positive

Collective emotions online and their influence on community life

E-communities, social groups interacting online, have recently become an object of interdisciplinary research. As with face-to-face meetings, Internet exchanges may not only include factual information but also emotional information - how participants feel about the subject discussed or other group members. Emotions are known to be important in affecting interaction partners in offline communication in many ways. Could emotions in Internet exchanges affect others and systematically influence quantitative and qualitative aspects of the trajectory of e-communities? The development of automatic sentiment analysis has made large scale emotion detection and analysis possible using text messages collected from the web. It is not clear if emotions in e-communities primarily derive from individual group members' personalities or if they result from intra-group interactions, and whether they influence group activities. We show the collective character of affective phenomena on a large scale as observed in 4 million posts downloaded from Blogs, Digg and BBC forums. To test whether the emotions of a community member may influence the emotions of others, posts were grouped into clusters of messages with similar emotional valences. The frequency of long clusters was much higher than it would be if emotions occurred at random. Distributions for cluster lengths can be explained by preferential processes because conditional probabilities for consecutive messages grow as a power law with cluster length. For BBC forum threads, average discussion lengths were higher for larger values of absolute average emotional valence in the first ten comments and the average amount of emotion in messages fell during discussions. Our results prove that collective emotional states can be created and modulated via Internet communication and that emotional expressiveness is the fuel that sustains some e-communities.Comment: 23 pages including Supporting Information, accepted to PLoS ON

T Lymphocytes Promote the Antiviral and Inflammatory Responses of Airway Epithelial Cells

T cells modulate the antiviral and inflammatory responses of airway epithelial cells to human rhinoviruses (HRV)

Dupuytren's contracture: a retrospective database analysis to determine hospitalizations in the Netherlands

Background: Dupuytren's contracture is a condition of the palmar fascia involving contractures of the fascia and skin in the hand. Current treatment for Dupuytren's contracture is mainly limited to surgery. In the Netherlands, little is known about the prevalence of Dupuytren's contracture. In this study we determined the prevalence of patients with a hospitalization for Dupuytren's contracture in the Netherlands and characterized their (re)hospitalizations. Methods. From the PHARMO database, which consists of multiple observational databases linked on a patient level, all patients hospitalized for Dupuytren's contracture between 2004 and 2007 were included in the source population (ICD-9-CM code 728.6). Numbers from this source population were used to provide estimates of hospitalizations for Dupuytren's contracture in the Netherlands. Patients with a medical history in the PHARMO database of at least 12 months before their hospitalization were included in the study cohort and followed until end of data collection, death, or end of study period, whichever occurred first. Type of admission, length of stay, recorded procedures, treating specialty, number of rehospitalizations for Dupuytren's contracture, and time to first rehospitalization were assessed. Results: Of 3, 126 patients included in the source population, 3, 040 were included in the study population. The overall prevalence of patients with a hospitalization for Dupuytren'

Performance of two questionnaires to measure treatment adherence in patients with Type-2 Diabetes

<p>Abstract</p> <p>Background</p> <p>Most valid methods to measure treatment adherence require time and resources, and they are not easily applied in highly demanding Primary Health Care Clinics (PHCC). The objective of this study was to determine sensitivity, specificity, predictive values, likelihood ratios, and post-test probabilities of two novel questionnaires as proxy measurements of treatment adherence in Type-2 diabetic patients.</p> <p>Methods</p> <p>Two questionnaires were developed by a group of experts to identify the patient's medical prescription knowledge (knowledge) and their attitudes toward treatment adherence (attitudes) as proxy measurements of adherence. The questionnaires were completed by patients receiving care in PHCC pertaining to the Mexican Institute of Social Security in Aguascalientes (Mexico). Pill count was used as gold standard. Participants were selected randomly, and their oral hypoglycemic prescriptions were studied. The main outcome measures for each questionnaire were sensitivity, specificity, predictive values, likelihood ratios, and post-test probabilities, all as an independent questionnaire test and in a serial analysis.</p> <p>Results</p> <p>Adherence prevalence was 27.0% using pill count. Knowledge questionnaire showed the highest sensitivity (68.1%) and negative predictive value (82.2%), the lowest negative likelihood ratio (0.58) and post-test probability for a negative result (0.16). Serial analysis showed the highest specificity (77.4%) and positive predictive value (40.1%) as well as the highest positive likelihood ratio (1.8) and post-test probability for a positive result (0.39).</p> <p>Conclusion</p> <p>Medical Prescription Knowledge questionnaire showed the best performance as proxy measurement to identify non-adherence in type 2 diabetic patients regarding negative predictive value, negative likelihood ratio, and post-test probability for a negative result. However, Medical Prescription Knowledge questionnaire performance may change in contexts with higher adherence prevalence. Therefore, more research is needed before using this method in other contexts.</p

Adherence to secondary prophylaxis and disease recurrence in 536 Brazilian children with rheumatic fever

<p>Abstract</p> <p>Background</p> <p>More than 15 million people worldwide have rheumatic fever (RF) and rheumatic heart disease due to RF. Secondary prophylaxis is a critical cost-effective intervention for preventing morbidity and mortality related to RF. Ensuring adequate adherence to secondary prophylaxis for RF is a challenging task. This study aimed to describe the rates of recurrent episodes of RF, quantify adherence to secondary prophylaxis, and examine the effects of medication adherence to the rates of RF in a cohort of Brazilian children and adolescents with RF.</p> <p>Methods</p> <p>This retrospective study took place in the Pediatric Rheumatology outpatient clinic at a tertiary care hospital (Instituto de Puericultura e Pediatria Martagão Gesteira) in Rio de Janeiro, Brazil, and included patients with a diagnosis of RF from 1985 to 2005.</p> <p>Results</p> <p>536 patients with RF comprised the study sample. Recurrent episodes of RF occurred in 88 of 536 patients (16.5%). Patients with a recurrent episode of RF were younger (p < 0.0001), more frequently males (p = 0.003), and less adherent (p < 0.0001) to secondary prophylaxis than patients without RF recurrence. Non-adherence to medication at any time during follow-up was detected in 35% of patients. Rates of non-adherence were higher in the group of patients that were lost to follow-up (42%) than in the group of patients still in follow-up (32%) (p = 0.027). Appointment frequency was inadequate in 10% of patients. Higher rates of inadequate appointment frequency were observed among patients who were eventually lost to follow-up (14.5%) than in patients who were successfully followed-up (8%) (p = 0.022). 180 patients (33.5%) were lost to follow up at some point in time.</p> <p>Conclusions</p> <p>We recommend implementation of a registry, and a system of active search of missing patients in every service responsible for the follow-up of RF patients. Measures to increase adherence to secondary prophylaxis need to be implemented formally, once non-adherence to secondary prophylaxis is the main cause of RF recurrence. Detection of irregularity in secondary prophylaxis or in appointments should be an alert about the possibility of loss of follow-up and closer observation should be instituted.</p