2,091 research outputs found
Inflorescence stem grafting made easy in Arabidopsis
UNLABELLED BACKGROUND Plant grafting techniques have deepened our understanding of the signals facilitating communication between the root and shoot, as well as between shoot and reproductive organs. Transmissible signalling molecules can include hormones, peptides, proteins and metabolites: some of which travel long distances to communicate stress, nutrient status, disease and developmental events. While hypocotyl micrografting techniques have been successfully established for Arabidopsis to explore root to shoot communications, inflorescence grafting in Arabidopsis has not been exploited to the same extent. Two different strategies (horizontal and wedge-style inflorescence grafting) have been developed to explore long distance signalling between the shoot and reproductive organs. We developed a robust wedge-cleft grafting method, with success rates greater than 87%, by developing better tissue contact between the stems from the inflorescence scion and rootstock. We describe how to perform a successful inflorescence stem graft that allows for reproducible translocation experiments into the physiological, developmental and molecular aspects of long distance signalling events that promote reproduction. RESULTS Wedge grafts of the Arabidopsis inflorescence stem were supported with silicone tubing and further sealed with parafilm to maintain the vascular flow of nutrients to the shoot and reproductive tissues. Nearly all (87%) grafted plants formed a strong union between the scion and rootstock. The success of grafting was scored using an inflorescence growth assay based upon the growth of primary stem. Repeated pruning produced new cauline tissues, healthy flowers and reproductive siliques, which indicates a healthy flow of nutrients from the rootstock. Removal of the silicone tubing showed a tightly fused wedge graft junction with callus proliferation. Histological staining of sections through the graft junction demonstrated the differentiation of newly formed vascular connections, parenchyma tissue and lignin accumulation, supporting the presumed success of the graft union between two sections of the primary inflorescence stem. CONCLUSIONS We describe a simple and reliable method for grafting sections of an Arabidopsis inflorescence stem. This step-by-step protocol facilitates laboratories without grafting experience to further explore the molecular and chemical signalling which coordinates communications between the shoot and reproductive tissues
Use of prenatal testing, emotional attachment to the fetus and fetal health locus of control
This study examines the relationship between maternal emotional attachment to the fetus, beliefs about fetal health locus of control, and use of prenatal testing (i.e., amniocentesis and maternal serum screening). To date, no research has directly addressed the link between these psychosocial variables and prenatal testing uptake. Ninety-one pregnant women at risk for fetal abnormalities (i.e., 35 years of age or older) participated in the study, of whom 35 had no testing, 27 had serum screening, and 29 had amniocentesis in their current pregnancy.
Results of a hierarchical multiple regression partially supported the hypothesis that internal and powerful others Fetal Health Locus of Control (Labs & Wurtele, 1986) and prenatal testing status would be predictive of attachment (Prenatal Attachment Inventory; Muller, 1993) over and above the effects of gestational age, maternal age and attitude toward abortion. Fetal Health Locus of Control beliefs regarding oneâs own role (FHLC-I) in determining the health of oneâs fetus were found to be predictive of prenatal attachment. Results failed to support the hypothesis that the role of health professionals (FHLC-P) would be predictive of prenatal attachment. As predicted, women who had not used prenatal testing or who underwent amniocentesis tended to have stronger prenatal attachment than those who underwent serum screening only.
Results supported the hypotheses that stronger attachment to the fetus would be positively correlated with both FHLC-I and FHLC-P scores. Women who had no testing were found to hold less favourable attitudes toward abortion and rate their religious as stronger than those who had amniocentesis. Emotional attachment to the fetus was stronger among women who had previous miscarriages than those who had not, but did not differ between women who had a previous abortion and those who had not
Image Processing: How the Retina Detects the Direction of Image Motion
In the retina, the beautifully symmetrical âstarburstâ amacrine cells interact with each other in a way that creates asymmetrical responses to moving images at their dendritic tips. This computation, occurring in a retinal interneuron, is a foundation of the directional signals transmitted by the retina to the brain
Atlas of Myriapod Biogeography. I. Indigenous Ordinal and Supra-Ordinal Distributions in the Diplopoda: Perspectives on Taxon Origins and Ages, and a Hypothesis on the Origin and Early Evolution of the Class
The biogeographic significance of Diplopoda is substantiated by 50 maps documenting indigenous occurrences of the 16 orders, the three Spirostreptida s. l. suborders â Cambalidea, Epinannolenidea, Spirostreptidea â and all higher taxa including Diplopoda itself. The class is indigenous to all continents except Antarctica and islands/archipelagos in all temperate and tropical seas and oceans except the Arctic; it ranges from Kodiak Island and the northern Alaskan Panhandle, United States (USA), southern Hudson Bay, Canada, and near or north of the Arctic Circle in Iceland, continental Scandinavia, and Siberia to southern âmainlandâ Argentina, the southern tips of Africa and Tasmania, and Campbell Island, subantarctic New Zealand. The vast, global distribution is interrupted by sizeable, poorly- or unsampled areas including the Great Basin, USA; the Atacama Desert region of Chile and neighboring countries; southern South American islands; the central Kalahari and Sahara deserts; the Gobi Desert, Mongolia, and all of north-central and western China; from north of the Caspian Sea, Russia, to central Kazakhstan; and the âOutbackâ of central Australia. Five Arabian countries lack both samples and published records of indigenous diplopods â Bahrain, Kuwait, Oman, Qatar, and United Arab Emirates â as do Turks and Caicos, in the New World, and Mauritania and possibly Egypt, Africa. New records, including the first for Chilognatha from Botswana and the first specific localities from Northern Territory, Australia, are cited in the Appendix. Increased emphasis on mappings in taxonomic research is warranted along with investigations of insular âspecies swarmsâ that constitute a microcosm of the early evolution of the class. The largest âspecies swarmâ in the Diplopoda is Diplopoda itself!
Four taxa â Glomerida, Platydesmida, Julida, and Callipodida â occur exclusively in former Laurasian Territory, and seven â Glomeridesmida, Sphaerotheriida, Siphonophorida, Spirobolida, Epinannolenidea, Spirostreptidea, and Stemmiulida â all absent from Europe, are primarily southern/Gondwanan except for secondary dispersals in Mexico/Central America by all but Sphaerotheriida, which are absent from the New World. Siphoniulida and Siphonocryptida, known from only two and four areas, respectively, are declining towards extinction; the former may constitute a relictual intermediate between Colobognatha and Eugnatha. Polyxenida, Polyzoniida, Chordeumatida, and Polydesmida occur on nearly all continents, while Cambalidea, extinct in Europe, inhabit North/Central America and southeast Asia with an isolated area in Iran. Southeast Asia, from southern China to Sumatra, harbors all 16 orders plus Cambalidea and Spirostreptidea. Southern taxa were passively transported to Asia beginning in the Silurian on terranes that rifted from the âproto-Australiaâ area of the Gondwana deriving from breakup of the supercontinent Pannotia (hereafter âGondwana Iâ); they drifted northwards and accreted to Siberia+Kazakhstania/âEuramerica,â and later the âproto-Laurasiaâ part of Pangaea, from the Permian to the Jurassic. Laurasian taxa could not penetrate southeastern Asia until those terranes had accreted and the region was available for colonization; before this, they evolved, differentiated, and dispersed east/southeastward from source areas in Euramerica, as evidenced by detached faunal remnants in present-day Central Asia and the Himalayas. Southeastern Asia is thus a âmixing areaâ for northern and southern diplopods as is Mexico/Central America, which Gondwanan forms entered in the Late Carboniferous, ~ 306 ma, when Euramerica collided with the âproto-South America/Africaâ region of Gondwana I, thereby forming Western Pangaea. Closure of the Panama Portal in the Pliocene, ~ 5 ma, allowed northward dispersals of South American forms but is too recent to account for occurrences throughout the Central American land bridge and even into the USA, though it probably explains northward spread of Epinannolenidea and the polydesmidan family Paradoxosomatidae to Costa Rica. Occurrence of the latter in Dominica, Lesser Antilles, is regarded as indigenous rather than introduced and probably represents occurrence in the âProto-Antilleanâ area before it rifted from northern South America in the Cretaceous/ Paleocene, ~ 66 ma.
As the earliest Paleozoic fossil is from Scottish Silurian deposits, an operative hypothesis explaining early diplopod evolution requires origin far enough before then for major dichotomies to have taken place and for ancestral forms to have dispersed and become established relatively simultaneously on both Gondwana I and the northern âmicro-continentsâ (Baltica, Laurentia, and Siberia). Only one source area meets these requirements, the Avalonia terrane of Gondwana I before it rifted in the early Ordovician (~ 480 ma) and drifted to and combined with Baltica in the mid-Ordovician (~ 450 ma); 10 my later, Baltica+Avalonia merged with Laurentia to form Euramerica. Presence on Avalonia and neighboring parts of Gondwana I prior to rifting mandates at least Mid- to Late Cambrian origin ( \u3c 524 ma) on or near this terrane with rapid divergence and dispersal onto Gondwana I proper, such that ancestral stock was partitioned when Avalonia rifted. Forms remaining on Gondwana I continued to evolve, differentiate, and disperse, eventually reaching the âproto-east/southeast Asiaâ terranes before they rifted, while those on Avalonia were confined to this terrane until collisions with Baltica and Laurentia allowed them to colonize these unoccupied lands with numerous vacant niches, which drove evolution in different directions from that taking place simultaneously and in âparallelâ on Gondwana I.
Relative ordinal-group ages are postulated as Polyxenida \u3e Polydesmida \u3e Siphoniulida \u3e Siphonocryptida \u3e Spirostreptida s. l./Cambalidea \u3e Chordeumatida \u3e Polyzoniida \u3e Glomeridesmida \u3e Sphaerotheriida \u3e Epinannolenidea \u3e Stemmiulida ~ Siphonophorida \u3e Spirobolida \u3e Spirostreptidea \u3e Glomerida ~ Platydesmida \u3e Callipodida \u3e Julida.
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Investigating the Integration of Student Learning Resources in Preparation for the NCLEX-RN: Phase One of a Canadian Two-Phase Multi-Site Study
Evidence-informed education practices are critical in determining effective student preparatory learning resources for the NCLEX-RN examination. Standardized testing in nursing education programs has been demonstrated to increase students NCLEX-RN success. A widely researched assessment tool for predicting NCLEX-RN examination outcomes is the HESITM RN Exit Exams. The HESI Exit Exam (E2) was determined to be between 93.36% and 99.16% accurate in predicting NCLEX-RN success (N = 49,115) with samples derived from various nursing programs throughout the United States.
Purpose: This two-phase, multi-site ex-post facto study was to investigate NCLEX-RN Student Preparatory Learning Resources within the Canadian context. Phase One, which is reported here, was to determine if there was a relationship between student HESITM RN Exit and Computer Adaptive Testing (CAT) Exam scores, student grade point average (GPA), and the time lag between graduation and writing the National Licensure exam, and student outcome on the NCLEX-RN exam.
Procedure: New nursing graduates were emailed study information and asked to provide their consent for the use of their student data (GPA, HESITM Exit and CAT Exam scores) for research purposes and to request that they self-report (via a password protected secure email address created for this study) their NCLEX-RN Licensure exam date and result (pass/fail) of their first exam writing.
Results: Among a convenience sample of 117 new nursing alumni (graduates of 2015) from three universities in Nova Scotia, we found statistically significant mean differences in HESITM RN Exit Exam Version 1, Version 2, and CAT scores among those students that were successful on the NCLEX-RN exam versus those students that were not successful on their first writing of the NCLEX-RN exam. There was an inverse statistically significant relationship between time lag and NCLEX-RN outcome indicating that the longer the time period from graduation to writing, the less likely that the student will be successful. We found no relationship between student GPA and NCLEX-RN outcome.
Discussion: Phase One results of this study suggest that there are differences in HESITM RN Exit exam and CAT scores among those students who were successful on the first write of NCLEX-RN exam versus those students who were not successful.. Although HESITM exams are just one type of the many available nursing resources to assist students to prepare for writing the National Licensure examination, our findings are significant and warrant Canadian nurse educatorsâ attention.
Résumé
Les pratiques de formation fondĂ©es sur des rĂ©sultats probants sont essentielles pour dĂ©terminer lâefficacitĂ© des ressources dâapprentissage prĂ©paratoires Ă lâexamen NCLEX-RN offertes aux Ă©tudiantes. Il a Ă©tĂ© dĂ©montrĂ© que lâutilisation dâexamens standardisĂ©s dans les programmes de formation en sciences infirmiĂšres augmente le taux de rĂ©ussite des Ă©tudiants Ă lâexamen NCLEX-RN. Un outil dâĂ©valuation qui a Ă©tĂ© largement Ă©tudiĂ© et qui permet de prĂ©dire les rĂ©sultats dâexamen au NCLEX-RN est lâexamen final HESIMD RN. Il a Ă©tĂ© dĂ©terminĂ© que lâexamen final HESI (E2) prĂ©disait avec une prĂ©cision se situant entre 93,36 % et 99,16 % le taux de rĂ©ussite Ă lâexamen NCLEX-RN (N = 49 115) dans des Ă©chantillons provenant de diffĂ©rents programmes de sciences infirmiĂšres aux Ătats-Unis.
Objectif : Cette Ă©tude multi-sites, en deux phases, rĂ©alisĂ©e a posteriori visait Ă examiner les ressources dâapprentissage prĂ©paratoires au NCLEX-RN offertes aux Ă©tudiantes dans le contexte canadien. La premiĂšre phase, dont il est question dans cet article, Ă©tait conçue pour dĂ©terminer sâil existait une relation entre les rĂ©sultats dâexamens finaux au HESIMD RN, les rĂ©sultats au test adaptatif informatisĂ© (TAI), la moyenne gĂ©nĂ©rale (MG) des Ă©tudiants, lâintervalle de temps entre lâobtention du diplĂŽme et le passage de lâexamen national dâautorisation Ă exercer, et les rĂ©sultats Ă lâexamen NCLEX-RN.
ProcĂ©dure : Les nouvelles diplĂŽmĂ©es en sciences infirmiĂšres recevaient un courriel fournissant des informations sur lâĂ©tude et sollicitant leur consentement pour lâutilisation de donnĂ©es de leur dossier dâĂ©tudiante (leur MG, leur rĂ©sultat Ă lâexamen final HESIMD et leur rĂ©sultat au TAI) Ă des fins de recherche. Ce message leur demandait Ă©galement de dĂ©clarer (par lâentremise dâune adresse courriel sĂ©curisĂ©e protĂ©gĂ©e par mot de passe et crĂ©Ă©e pour lâĂ©tude) la date et le rĂ©sultat (rĂ©ussite/Ă©chec) de leur premier examen dâautorisation Ă exercer NCLEX-RN.
RĂ©sultats : Dans lâĂ©chantillon de convenance de 117 nouvelles diplĂŽmĂ©es en sciences infirmiĂšres (diplĂŽmĂ©es de 2015) de trois universitĂ©s en Nouvelle-Ăcosse, nous avons dĂ©couvert des diffĂ©rences de moyennes statistiquement significatives entre les Ă©tudiantes qui ont rĂ©ussi Ă lâexamen NCLEX-RN et celles qui ne lâont pas rĂ©ussi Ă la premiĂšre tentative, pour leurs rĂ©sultats Ă lâexamen final HESIMD RN, version 1 et version 2, et les rĂ©sultats du TAI. . Une relation inverse statistiquement significative fut remarquĂ©e entre lâintervalle de temps avant de passer lâexamen NCLEX-RN et le rĂ©sultat Ă âcet examen, ce qui indique que plus la pĂ©riode est longue entre lâobtention du diplĂŽme et le passage de lâexamen, moins il est probable que lâĂ©tudiante rĂ©ussisse lâexamen. Nous nâavons trouvĂ© aucune relation entre la MG de lâĂ©tudiante et le rĂ©sultat au NCLEX-RN.
Discussion : Les rĂ©sultats de la premiĂšre phase de cette Ă©tude indiquent quâil existe des diffĂ©rences quant aux rĂ©sultats Ă lâexamen final HESIMD RN et au TAI entre les Ă©tudiantes qui ont rĂ©ussi lâexamen NCLEX-RN la premiĂšre fois et celles qui lâont Ă©chouĂ©. Bien que les examens HESIMD ne soient quâun type de ressources parmi de nombreuses autres ressources disponibles en sciences infirmiĂšres pour aider les Ă©tudiantes Ă se prĂ©parer Ă lâexamen national dâautorisation Ă exercer, nos rĂ©sultats sont significatifs et mĂ©ritent lâattention des infirmiĂšres formatrices canadiennes
Spacelab energetic ion mass spectrometer
Basic design criteria are given for an ion mass spectrometer for use in studying magnetospheric ion populations. The proposed instrument is composed of an electrostatic analyzer followed by a magnetic spectrometer and simultaneously measures the energy per unit and mass per unit charge of the ion species. An electromagnet is used for momentum analysis to extend the operational energy range over a much wider domain than is possible with the permanent magnets used in previous flights. The energetic ion source regions, ion energization mechanisms, field line tracing, coordinated investigations, and orbit considerations are discussed and operations of the momentum analyzer and of the electrostatic energy analyzer are examined
Optimizing Strategies to Improve Interprofessional Practice for Veterans, Part 1
A grant from the One-University Open Access Fund at the University of Kansas was used to defray the authorâs publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Introduction
Interprofessional patient care is a well-recognized path that health care systems are striving toward. The Veteranâs Affairs (VA) system initiated interprofessional practice (IPP) models with their Geriatric Evaluation and Management (GEM) programs. GEM programs incorporate a range of specialties, including but not limited to, medicine, nursing, social work, physical therapy and pharmacy, to collaboratively evaluate veterans. Despite being a valuable resource, they are now faced with significant cut-backs, including closures. The primary goal of this project was to assess how the GEM model could be optimized at the Pittsburgh, Pennsylvania VA to allow for the sustainability of this important IPP assessment. Part 1 of the study evaluated the IPP process using program, patient, and family surveys. Part 2 examined how well the geriatrician matched patients to specialists in the GEM model. This paper describes Part 1 of our study.
Methods
Three strategies were used: 1) a national GEM program survey; 2) a veteran/family satisfaction survey; and 3) an absentee assessment.
Results
Twenty-six of 92 programs responded to the GEM IPP survey. Six strategies were shared to optimize IPP models throughout the country. Of the 34 satisfaction surveys, 80% stated the GEM clinic was beneficial, 79% stated their concerns were addressed, and 100% would recommend GEM to their friends. Of the 24 absentee assessments, the top three reasons for missing the appointments were transportation, medical illnesses, and not knowing/remembering about the appointment. Absentee rate diminished from 41% to 19% after instituting a reminder phone call policy.
Discussion
Maintaining the sustainability of IPP programs is crucial for the health of our veterans. This project uncovered tools to improve the GEM IPP model for our veterans that can be incorporated nationally. Despite the lengthy nature of IPP models, patients and families appreciated the thoroughness, requested transportation and food, and responded well to reminder phone calls. A keen eye on these issues and concomitant medical complexity needs to be observed when planning IPP models to ensure sustainability
Blackflies (Diptera: Simuliidae) of Southern Guyana with keys for the identification of adults and pupae: a review
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