870 research outputs found
LA ESTRUCTURA DE LA FAMILIA Y LA FERTILIDAD EN PUERTO RICO.
This is a report of the findings from a survey of attitudes and behavior with respect to birth control. The survey was conducted in 1953-54, and involved interviews of approximately one hour with lower class families marriedIess than zo years. Studies prior to this survey had shown 'that rnost Puerto Rican families have more children than they want to have. These earlier studies had also shown that the discrepancy was apparently not due to lack of knokwledge about birth control, unavailability of birth control material s, or religious objections to contraception. Exploratory studies by the authors of this article had suggested further factors which might explain the difference. These were tested by the survey. The dependent variable "family planning" was divided into the following categories: NevĂ©r Users, Quitters, Current Users, and Sterilized. Five blocks of independent variables were included in the interview. They were: 1. General Value System: Fatalism-striving, traditionalism-modernism, aspirations for self and children, and tendencies toward general planning. 2. Family Action Possibilities: Marital happiness, agreement on general issues, sexual satisfaction, communication on general issues, communication on family size ideals and birth control, modesty handicaps, familistic organization types, family readiness of actionon birth control. 3. Specijic Family Size Attitedes: Attitudes towards importance of children, ideal family size, sense of pressure of fertility on family resources, interest in spacing children. 4. Informational and Attitudinal Attributes: Information on methods, attitudes toward birth control, agreement on birth control. 5. Background Factors: Residence, occupation,education, religiĂłn, rental value of house, type of marital union, age at marriage. The hypotheses were that successful use of birth control would be associated with (1) modernism-striving-planning; (2) happiness-agreement-communication-readiness; (3) sma11 family mindedness; and ( 4) know'ledge about and favorable attitudes toward birth control methods. In addition, it was hypothesized that each of these four blocks of variableswould be related to each other in the same ways. The hypotheses with respect to background variables were less conventional. It was hypothesized that religious affiliation (catholic-protestant) would fail to differentiate; that economic status and education would not-differentiate (because the sample is limited to lower class); ,that YOllfiger wives are less likely to practice birth control; and that rural, consensually .married families will prefer large families. There are more than 8,000 separate hypotheses which rnight be tested if a11 variables of each "block" are tabulated with a11 variables ofevery other block", Of the 8,000, 81 wereseleeted. Of these 81 -associations,47 were found to be significant at the 5 per cent level, 29 we,:e not significant, and 5 reversed theexpected relationship. The five unexpected findings included: (a)rural.consensual marriages werethe most favorable (rather than the .least favorable) toward small families, · (b) subjects using birth control were likely to be less satisfied (rather than more satisfied) with general life conditions, and (c) in families where birth control had long been used, the wife was likely tĂș be less satisfied (rather. than more sĂĄtisfied) sexuapy. The authors conclude that the foflowing factors are. important for effective planning;: (1) a general "modera" value system; (2) definite views favoring sma11 families, (3) sufficient information on birth control methods and favorable attitudes towards using them; and (4}. effectlve family organization.Resumen en inglĂ©s
Towards an Intelligent Tutor for Mathematical Proofs
Computer-supported learning is an increasingly important form of study since
it allows for independent learning and individualized instruction. In this
paper, we discuss a novel approach to developing an intelligent tutoring system
for teaching textbook-style mathematical proofs. We characterize the
particularities of the domain and discuss common ITS design models. Our
approach is motivated by phenomena found in a corpus of tutorial dialogs that
were collected in a Wizard-of-Oz experiment. We show how an intelligent tutor
for textbook-style mathematical proofs can be built on top of an adapted
assertion-level proof assistant by reusing representations and proof search
strategies originally developed for automated and interactive theorem proving.
The resulting prototype was successfully evaluated on a corpus of tutorial
dialogs and yields good results.Comment: In Proceedings THedu'11, arXiv:1202.453
The diastereoselective Meth-Cohn epoxidation of camphor-derived vinyl sulfones
Some camphor-derived vinyl sulfones bearing oxygen functionality at the allylic position have been synthesized and their nucleophilic epoxidation reactions under Meth-Cohn conditions have been explored. The Îł-oxygenated camphor-derived vinyl sulfones underwent mildly diastereoselective nucleophilic epoxidation reactions, affording the derived sulfonyloxiranes in up to 5.8:1 dr. The observed diastereoselectivities were sensitive to the reaction conditions employed. In contrast, no stereoselectivity was observed in the nucleophilic epoxidation of the corresponding Îł-oxygenated isobornyl vinyl sulfone. A tentative mechanism has been proposed to explain the origins of the diastereoselectivit
Neutrophil cell surface receptors and their intracellular signal transduction pathways
AbstractNeutrophils play a critical role in the host defense against bacterial and fungal infections, but their inappropriate activation also contributes to tissue damage during autoimmune and inflammatory diseases. Neutrophils express a large number of cell surface receptors for the recognition of pathogen invasion and the inflammatory environment. Those include G-protein-coupled chemokine and chemoattractant receptors, Fc-receptors, adhesion receptors such as selectins/selectin ligands and integrins, various cytokine receptors, as well as innate immune receptors such as Toll-like receptors and C-type lectins. The various cell surface receptors trigger very diverse signal transduction pathways including activation of heterotrimeric and monomeric G-proteins, receptor-induced and store-operated Ca2+ signals, protein and lipid kinases, adapter proteins and cytoskeletal rearrangement. Here we provide an overview of the receptors involved in neutrophil activation and the intracellular signal transduction processes they trigger. This knowledge is crucial for understanding how neutrophils participate in antimicrobial host defense and inflammatory tissue damage and may also point to possible future targets of the pharmacological therapy of neutrophil-mediated autoimmune or inflammatory diseases
Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires
The production of tt⟠, W+bb⟠and W+cc⟠is studied in the forward region of protonâproton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fbâ1 . The W bosons are reconstructed in the decays WââÎœ , where â denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of , and is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 0.02 \mbox{fb}^{-1}. The bosons are reconstructed in the decays , where denotes muon or electron, while the and quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions
Multidifferential study of identified charged hadron distributions in -tagged jets in proton-proton collisions at 13 TeV
Jet fragmentation functions are measured for the first time in proton-proton
collisions for charged pions, kaons, and protons within jets recoiling against
a boson. The charged-hadron distributions are studied longitudinally and
transversely to the jet direction for jets with transverse momentum 20 GeV and in the pseudorapidity range . The
data sample was collected with the LHCb experiment at a center-of-mass energy
of 13 TeV, corresponding to an integrated luminosity of 1.64 fb. Triple
differential distributions as a function of the hadron longitudinal momentum
fraction, hadron transverse momentum, and jet transverse momentum are also
measured for the first time. This helps constrain transverse-momentum-dependent
fragmentation functions. Differences in the shapes and magnitudes of the
measured distributions for the different hadron species provide insights into
the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb
public pages
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