A survey of literature concerning the academic difficulties of bilingual Latins upon entering the public schools, and their possible solutions

Call number: LD2668 .R4 1966 R96

Species, Rotation, and Life-Form Diversity Effects on Soil Carbon in Experimental Tropical Ecosystems

Extensive areas of species-rich forests in the tropics have been replaced by tree monocultures over the last two decades, and the impact on biogeochemical cycles is unclear. We characterized effects on soil carbon dynamics of species identity and rotation frequency in experimental plantations containing three native, non-N-fixing tree species, Hyeronima alchoreoides, Cedrela odorata, and Cordia alliodora, grown in monocultures and in polycultures with two monocot species, Euterpe oleracea and Heliconia imbricata. Over all treatments, change in total soil organic carbon (TSOC, 0–15 cm) after 10 years ranged from a loss of 24% (0.9 mg/ha in 1-yr rotation of Cedrela) to an increase of 14% (0.6 mg/ha under Hyeronima polycultures). Species differed in their effects on quantities of TSOC (P = 0.038), but differences were more pronounced in light particulate organic matter (LPOM; P = 0.001), a biologically active, sand-size soil fraction that constituted 6% of TSOC. Effects of rotation frequency were strong; in Cedrela and Cordia, the 4-yr rotations had higher soil C stocks than did long-term monocultures, where soil C stocks had declined under 10-yr-old trees. Under Cedrela and Cordia, polycultures had significantly higher stocks of soil C than monocultures, whereas soil C stocks were high under Hyeronima in both cultures. In polycultures, Hyeronima dominated detrital inputs, contributing 88% of litterfall and fine-root growth, whereas Cedrela and Cordia contributed R2 = 0.70 and 0.14, respectively). These data suggested that roots drove soil C accrual in long-term rotations, and that mechanisms involving root chemistry, and not quantity of detrital inputs, best explained effects of species on soil C sequestration

Knowledge and Awareness Among Patients with Chronic Kidney Disease Stage 3

Knowledge is a prerequisite for changing behavior, and is useful for improving outcomes and reducing mortality rates in patients diagnosed with chronic kidney disease (CKD). The purpose of this article is to describe baseline CKD knowledge and awareness obtained as part of a larger study testing the feasibility of a self-management intervention. Thirty patients were recruited who had CKD Stage 3 with coexisting diabetes and hypertension. Fifty-four percent of the sample were unaware of their CKD diagnosis. Participants had a moderate amount of CKD knowledge. This study suggests the need to increase knowledge in patients with CKD Stage 3 to aid in slowing disease progression

Nitrogen fertilizer effects on soil carbon balances in Midwestern U.S. agricultural systems

A single ecosystem dominates the Midwestern United States, occupying 26 million hectares in five states alone: the corn–soybean agroecosystem [Zea mays L.–Glycine max (L.) Merr.]. Nitrogen (N) fertilization could influence the soil carbon (C) balance in this system because the corn phase is fertilized in 97–100% of farms, at an average rate of 135 kg N·ha−1·yr−1. We evaluated the impacts on two major processes that determine the soil C balance, the rates of organic-carbon (OC) inputs and decay, at four levels of N fertilization, 0, 90, 180, and 270 kg/ha, in two long-term experimental sites in Mollisols in Iowa, USA. We compared the corn–soybean system with other experimental cropping systems fertilized with N in the corn phases only: continuous corn for grain; corn–corn-oats (Avena sativa L.)–alfalfa (Medicago sativa L.; corn–oats–alfalfa–alfalfa; and continuous soybean. In all systems, we estimated long-term OC inputs and decay rates over all phases of the rotations, based on long-term yield data, harvest indices (HI), and root : shoot data. For corn, we measured these two ratios in the four N treatments in a single year in each site; for other crops we used published ratios. Total OC inputs were calculated as aboveground plus belowground net primary production (NPP) minus harvested yield. For corn, measured total OC inputs increased with N fertilization (P \u3c 0.05, both sites). Belowground NPP, comprising only 6–22% of total corn NPP, was not significantly influenced by N fertilization. When all phases of the crop rotations were evaluated over the long term, OC decay rates increased concomitantly with OC input rates in several systems. Increases in decay rates with N fertilization apparently offset gains in carbon inputs to the soil in such a way that soil C sequestration was virtually nil in 78% of the systems studied, despite up to 48 years of N additions. The quantity of belowground OC inputs was the best predictor of long-term soil C storage. This indicates that, in these systems, in comparison with increased N-fertilizer additions, selection of crops with high belowground NPP is a more effective management practice for increasing soil C sequestration

The Feasibility of a Using a Smart Button Mobile Health System to Self-Track Medication Adherence and Deliver Tailored Short Message Service Text Message Feedback

BACKGROUND: As many as 50% of people experience medication nonadherence, yet studies for detecting nonadherence and delivering real-time interventions to improve adherence are lacking. Mobile health (mHealth) technologies show promise to track and support medication adherence. OBJECTIVE: The study aimed to evaluate the feasibility and acceptability of using an mHealth system for medication adherence tracking and intervention delivery. The mHealth system comprises a smart button device to self-track medication taking, a companion smartphone app, a computer algorithm used to determine adherence and then deliver a standard or tailored SMS (short message service) text message on the basis of timing of medication taking. Standard SMS text messages indicated that the smartphone app registered the button press, whereas tailored SMS text messages encouraged habit formation and systems thinking on the basis of the timing the medications were taken. METHODS: A convenience sample of 5 adults with chronic kidney disease (CKD), who were prescribed antihypertensive medication, participated in a 52-day longitudinal study. The study was conducted in 3 phases, with a standard SMS text message sent in phases 1 (study days 1-14) and 3 (study days 46-52) and tailored SMS text messages sent during phase 2 (study days 15-45) in response to participant medication self-tracking. Medication adherence was measured using: (1) the smart button and (2) electronic medication monitoring caps. Concordance between these 2 methods was evaluated using percentage of measurements made on the same day and occurring within ±5 min of one another. Acceptability was evaluated using qualitative feedback from participants. RESULTS: A total of 5 patients with CKD, stages 1-4, were enrolled in the study, with the majority being men (60%), white (80%), and Hispanic/Latino (40%) of middle age (52.6 years, SD 22.49; range 20-70). The mHealth system was successfully initiated in the clinic setting for all enrolled participants. Of the expected 260 data points, 36.5% (n=95) were recorded with the smart button and 76.2% (n=198) with electronic monitoring. Concordant events (n=94), in which events were recorded with both the smart button and electronic monitoring, occurred 47% of the time and 58% of these events occurred within ±5 min of one another. Participant comments suggested SMS text messages were encouraging. CONCLUSIONS: It was feasible to recruit participants in the clinic setting for an mHealth study, and our system was successfully initiated for all enrolled participants. The smart button is an innovative way to self-report adherence data, including date and timing of medication taking, which were not previously available from measures that rely on recall of adherence. Although the selected smart button had poor concordance with electronic monitoring caps, participants were willing to use it to self-track medication adherence, and they found the mHealth system acceptable to use in most cases

Revision of Madagascar's Dwarf Lemurs (Cheirogaleidae:Cheirogaleus): Designation of Species, Candidate Species Status and Geographic Boundaries Based on Molecular and Morphological Data

The genus Cheirogaleus, the dwarf lemurs, is a radiation of strepsirrhine primates endemic to the island of Madagascar. The dwarf lemurs are taxonomically grouped in the family Cheirogaleidae (Infraorder: Lemuriformes) along with the genera Microcebus, Mirza, Allocebus, and Phaner. The taxonomic history of the genus Cheirogaleus has been controversial since its inception due to a paucity of evidence in support of some proposed species. In this study, we addressed this issue by expanding the geographic breadth of samples by 91 individuals and built upon existing mitochondrial (cytb and COII) and nuclear (FIBA and vWF) DNA datasets to better resolve the phylogeny of Cheirogaleus. The mitochondrial gene fragments D-loop and PAST as well as the CFTR-PAIRB nuclear loci were also sequenced. In agreement with previous genetic studies, numerous deep divergences were resolved in the C. major, C. minor and C. medius lineages. Four of these lineages were segregated as new species, seven were identified as confirmed candidate species, and four were designated as unconfirmed candidate species based on comparative mitochondrial DNA sequence data gleaned from the literature or this study. Additionally, C. thomasi was resurrected. Given the widespread distribution of the genus Cheirogaleus throughout Madagascar, the methodology employed in this study combined all available lines of evidence to standardize investigative procedures in a genus with limited access to type material and a lack of comprehensive sampling across its total distribution. Our results highlighted lineages that likely represent new species and identified localities that may harbor an as-yet undescribed cryptic species diversity pending further field and laboratory work.We are most grateful to the Ahmanson Foundation, the Theodore F. and Claire M. Hubbard Family Foundation, the Primate Action Fund / Conservation International, the Margot Marsh Biodiversity Foundation, and the National Geographic Society, for financial assistance

Self-management interventions in stages 1 to 4 chronic kidney disease: an integrative review

The prevalence, effect on health outcomes, and economic impact of chronic kidney disease (CKD) have created interest in self-management interventions to help slow disease progression to kidney failure. Seven studies were reviewed to identify knowledge gaps and future directions for research. All studies were published between 2010 and 2013; no investigations were conducted in the United States. Knowledge gaps included the focus on medical self-management tasks with no attention to role or emotional tasks, lack of family involvement during intervention delivery, and an inability to form conclusions about the efficacy of interventions because methodological rigor was insufficient. Educational content varied across studies. Strategies to improve self-management skills and enhance self-efficacy varied and were limited in scope. Further development and testing of theory-based interventions are warranted. There is a critical need for future research using well-designed trials with appropriately powered sample sizes, well-tested instruments, and clear and consistent reporting of results

DEAD-Box Helicase Proteins Disrupt RNA Tertiary Structure Through Helix Capture

DEAD-box helicase proteins accelerate folding and rearrangements of highly structured RNAs and RNA–protein complexes (RNPs) in many essential cellular processes. Although DEAD-box proteins have been shown to use ATP to unwind short RNA helices, it is not known how they disrupt RNA tertiary structure. Here, we use single molecule fluorescence to show that the DEAD-box protein CYT-19 disrupts tertiary structure in a group I intron using a helix capture mechanism. CYT-19 binds to a helix within the structured RNA only after the helix spontaneously loses its tertiary contacts, and then CYT-19 uses ATP to unwind the helix, liberating the product strands. Ded1, a multifunctional yeast DEAD-box protein, gives analogous results with small but reproducible differences that may reflect its in vivo roles. The requirement for spontaneous dynamics likely targets DEAD-box proteins toward less stable RNA structures, which are likely to experience greater dynamic fluctuations, and provides a satisfying explanation for previous correlations between RNA stability and CYT-19 unfolding efficiency. Biologically, the ability to sense RNA stability probably biases DEAD-box proteins to act preferentially on less stable misfolded structures and thereby to promote native folding while minimizing spurious interactions with stable, natively folded RNAs. In addition, this straightforward mechanism for RNA remodeling does not require any specific structural environment of the helicase core and is likely to be relevant for DEAD-box proteins that promote RNA rearrangements of RNP complexes including the spliceosome and ribosome

Serologic Screening for Genital Herpes: An Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance: Genital herpes simplex virus (HSV) infection is a prevalent sexually transmitted infection. Vertical transmission of HSV can lead to fetal morbidity and mortality. Objective: To assess the evidence on serologic screening and preventive interventions for genital HSV infection in asymptomatic adults and adolescents to support the US Preventive Services Task Force for an updated recommendation statement. Data Sources: MEDLINE, Cochrane Library, EMBASE, and trial registries through March 31, 2016. Surveillance for new evidence in targeted publications was conducted through October 31, 2016. Study Selection: English-language randomized clinical trials (RCTs) comparing screening with no screening in persons without past or current symptoms of genital herpes; studies evaluating accuracy and harms of serologic screening tests for HSV-2; RCTs assessing preventive interventions in asymptomatic persons seropositive for HSV-2. Data Extraction and Synthesis: Dual review of abstracts, full-text articles, and study quality; pooled sensitivities and specificities of screening tests using a hierarchical summary receiver operating characteristic curve analysis when at least 3 similar studies were available. Main Outcomes and Measures: Accuracy of screening tests, benefits of screening, harms of screening, reduction in genital herpes outbreaks. Results: A total of 17 studies (n = 9736 participants; range, 24-3290) in 19 publications were included. No RCTs compared screening with no screening. Most studies of the accuracy of screening tests were from populations with high HSV-2 prevalence (greater than 40% based on Western blot). Pooled estimates of sensitivity and specificity of the most commonly used test at the manufacturer's cutpoint were 99% (95% CI, 97%-100%) and 81% (95% CI, 68%-90%), respectively (10 studies; n = 6537). At higher cutpoints, pooled estimates were 95% (95% CI, 91%-97%) and 89% (95% CI, 82%-93%), respectively (7 studies; n = 5516). Use of this test at the manufacturer's cutpoint in a population of 100 000 with a prevalence of HSV-2 of 16% (the seroprevalence in US adults with unknown symptom status) would result in 15 840 true-positive results and 15 960 false-positive results (positive predictive value, 50%). Serologic screening for genital herpes was associated with psychosocial harms, including distress and anxiety related to positive test results. Four RCTs compared preventive medications with placebo, 2 in nonpregnant asymptomatic adults who were HSV-2 seropositive and 2 in HSV-2-serodiscordant couples. Results in both populations were heterogeneous and inconsistent. Conclusions and Relevance: Serologic screening for genital herpes is associated with a high rate of false-positive test results and potential psychosocial harms. Evidence from RCTs does not establish whether preventive antiviral medication for asymptomatic HSV-2 infection has benefit