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1.
Contraception ; 101(1): 26-33, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655068

RESUMO

OBJECTIVES: To explore the reasons for discontinuation of the last contraceptive method used in women with a current unintended pregnancy. STUDY DESIGN: We conducted a retrospective analysis using contraceptive calendar data from Demographic and Health Surveys from 36 low- and middle-income countries from 2005 through 2014. The prevalence of contraception utilization and the contribution of each reason for contraceptive discontinuation was calculated, at country level as well as for the pooled dataset, for 10,901 women aged 15-49 before the current unintended pregnancies. RESULTS: Unintended pregnancies ranged from 5.5% of all pregnancies in the Kyrgyz Republic to 60.0% in Colombia and Peru. In Central Asian and in six African countries, over 80% of women with a current unintended pregnancy had not used any contraceptives in the previous five years. Use of long-acting modern methods remained consistently low across all countries. Among women who last used a traditional method, 83.8% discontinued due to failure. Among women who last used a long-acting modern method, 40.2% discontinued because of side effects. CONCLUSIONS: Our findings confirm that more than 65.0% of women with an unintended pregnancy in 36 low and middle-income countries were either non-users or using traditional methods. An additional 31.2% were using short-acting modern methods. Long-acting methods would have prevented the overwhelming majority of unintended pregnancies. IMPLICATIONS: This paper shows the need for the health system to support use of suitable methods, reduce switching failure and identify early when women are having concerns about the method they are using.


Assuntos
Comportamento Contraceptivo/estatística & dados numéricos , Anticoncepção/métodos , Gravidez não Planejada , Adolescente , Adulto , Anticoncepção/psicologia , Comportamento Contraceptivo/psicologia , Eficácia de Contraceptivos/estatística & dados numéricos , Países em Desenvolvimento , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez/estatística & dados numéricos , Estudos Retrospectivos , Inquéritos e Questionários , Adulto Jovem
2.
Phys Rev Lett ; 120(22): 221301, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29906152

RESUMO

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

3.
BJOG ; 124(10): 1558-1565, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27862850

RESUMO

OBJECTIVES: To determine the relation between place and skilled birth attendance at birth and early neonatal mortality. DESIGN: Retrospective analysis using data from Demographic and Health Surveys on obstetric complications. SETTING: Nine low and middle income countries between 2006 and 2013. POPULATION: 71 758 women aged 15-49 years. METHODS: A secondary analysis was carried out to investigate the occurrence and effect of obstetric complications on early neonatal mortality and association with place and attendance at birth. Obstetric complications studied were prolonged labour, puerperal infection and eclampsia. MAIN OUTCOME MEASURES: Association between early neonatal mortality and place and attendance at birth, unadjusted and adjusted for presence of severe obstetric complications. RESULTS: Thirty-five percent of all births were at home: 70% of these were without skilled attendamts. Obstetric complications were reported in 17 079 women: 82% of these women gave birth in health facilities. Overall, no association was observed between place of birth or attendance at birth and early neonatal mortality. When adjusted for obstetric complications, the odds of early neonatal deaths for births at home without a skilled attendant were 1.3 (95% CI 1.1-1.5) compared with 1.2 (95% CI 1.0-1.5) with a skilled attendant and births in health facilities. CONCLUSIONS: When adjusted for obstetric complications, births in health facilities were associated with reduced early neonatal mortality. However, reporting and referral bias account for at least part of the association. TWEETABLE ABSTRACT: Births in health facilities are linked with fewer early newborn deaths when adjusted for obstetric complications.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Instalações de Saúde/estatística & dados numéricos , Mortalidade Infantil , Tocologia/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Adolescente , Adulto , Demografia , Feminino , Parto Domiciliar/estatística & dados numéricos , Humanos , Lactente , Pessoa de Meia-Idade , Complicações do Trabalho de Parto/epidemiologia , Gravidez , Estudos Retrospectivos , Adulto Jovem
4.
Phys Rev Lett ; 115(12): 121803, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26430987

RESUMO

Search results for nucleon decays p→e^{+}X, p→µ^{+}X, n→νγ (where X is an invisible, massless particle) as well as dinucleon decays np→e^{+}ν, np→µ^{+}ν, and np→τ^{+}ν in the Super-Kamiokande experiment are presented. Using single-ring data from an exposure of 273.4 kton·yr, a search for these decays yields a result consistent with no signal. Accordingly, lower limits on the partial lifetimes of τ_{p→e^{+}X}>7.9×10^{32} yr, τ_{p→µ^{+}X}>4.1×10^{32} yr, τ_{n→νγ}>5.5×10^{32} yr, τ_{np→e^{+}ν}>2.6×10^{32} yr, τ_{np→µ^{+}ν}>2.2×10^{32} yr, and τ_{np→τ^{+}ν}>2.9×10^{31} yr at a 90% confidence level are obtained. Some of these searches are novel.

5.
Phys Rev Lett ; 114(14): 141301, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25910107

RESUMO

Super-Kamiokande (SK) can search for weakly interacting massive particles (WIMPs) by detecting neutrinos produced from WIMP annihilations occurring inside the Sun. In this analysis, we include neutrino events with interaction vertices in the detector in addition to upward-going muons produced in the surrounding rock. Compared to the previous result, which used the upward-going muons only, the signal acceptances for light (few-GeV/c^{2}-200-GeV/c^{2}) WIMPs are significantly increased. We fit 3903 days of SK data to search for the contribution of neutrinos from WIMP annihilation in the Sun. We found no significant excess over expected atmospheric-neutrino background and the result is interpreted in terms of upper limits on WIMP-nucleon elastic scattering cross sections under different assumptions about the annihilation channel. We set the current best limits on the spin-dependent WIMP-proton cross section for WIMP masses below 200 GeV/c^{2} (at 10 GeV/c^{2}, 1.49×10^{-39} cm^{2} for χχ→bb[over ¯] and 1.31×10^{-40} cm^{2} for χχ→τ^{+}τ^{-} annihilation channels), also ruling out some fraction of WIMP candidates with spin-independent coupling in the few-GeV/c^{2} mass range.

6.
Phys Rev Lett ; 113(12): 121802, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25279622

RESUMO

We present the results of searches for nucleon decay via n→ν[over ¯]π0 and p→ν[over ¯]π+ using data from a combined 172.8 kt·yr exposure of Super-Kamiokande-I,-II, and-III. We set lower limits on the partial lifetime for each of these modes: τn→ν[over ¯]π0>1.1×10(33) years and τp→ν[over ¯]π+>3.9×10(32) years at a 90% confidence level.

7.
Phys Rev Lett ; 113(10): 101801, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25238348

RESUMO

The trilepton nucleon decay modes p→e+νν and p→µ+νν violate |Δ(B-L)| by two units. Using data from a 273.4 kt yr exposure of Super-Kamiokande a search for these decays yields a fit consistent with no signal. Accordingly, lower limits on the partial lifetimes of τp→e+νν>1.7×10(32) years and τp→µ+νν>2.2×10(32) years at a 90% confidence level are obtained. These limits can constrain Grand Unified Theories which allow for such processes.

8.
BJOG ; 121 Suppl 4: 154-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25236650

RESUMO

In the World Health Organization Western Pacific Region, the high rates of births attended by skilled health personnel (SHP) do not equal access to quality maternal or newborn care. 'A healthy start for every newborn' for 23 million annual births in the region means that SHP and newborn care providers give quality intrapartum, postpartum and newborn care. WHO and the UNICEF Regional Action Plan for Healthy Newborn Infants provide a platform for countries to scale-up Early Essential Newborn Care (EENC). The plan emphasises the creation of an enabling environment for the practice of EENC; thereby, preventing 50,000 newborn deaths annually.


Assuntos
Assistência Perinatal/organização & administração , Assistência Perinatal/normas , Qualidade da Assistência à Saúde , Sudeste Asiático , Programas Gente Saudável , Humanos , Tocologia , Estudos de Casos Organizacionais , Filipinas , Cuidado Pós-Natal/normas , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde/organização & administração , Organização Mundial da Saúde
9.
Phys Rev Lett ; 112(9): 091805, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24655245

RESUMO

We report an indication that the elastic scattering rate of solar B8 neutrinos with electrons in the Super-Kamiokande detector is larger when the neutrinos pass through Earth during nighttime. We determine the day-night asymmetry, defined as the difference of the average day rate and average night rate divided by the average of those two rates, to be [-3.2 ± 1.1(stat) ± 0.5(syst)]%, which deviates from zero by 2.7 σ. Since the elastic scattering process is mostly sensitive to electron-flavored solar neutrinos, a nonzero day-night asymmetry implies that the flavor oscillations of solar neutrinos are affected by the presence of matter within the neutrinos' flight path. Super-Kamiokande's day-night asymmetry is consistent with neutrino oscillations for 4 × 10(-5) eV(2) ≤ Δm 2(21) ≤ 7 × 10(-5) eV(2) and large mixing values of θ12, at the 68% C.L.

10.
Phys Rev Lett ; 110(18): 181802, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23683190

RESUMO

Super-Kamiokande atmospheric neutrino data were fit with an unbinned maximum likelihood method to search for the appearance of tau leptons resulting from the interactions of oscillation-generated tau neutrinos in the detector. Relative to the expectation of unity, the tau normalization is found to be 1.42 ± 0.35(stat)(-0.12)(+0.14)(syst) excluding the no-tau-appearance hypothesis, for which the normalization would be zero, at the 3.8σ level. We estimate that 180.1 ± 44.3(stat)(-15.2)(+17.8) (syst) tau leptons were produced in the 22.5 kton fiducial volume of the detector by tau neutrinos during the 2806 day running period. In future analyses, this large sample of selected tau events will allow the study of charged current tau neutrino interaction physics with oscillation produced tau neutrinos.

11.
Phys Rev Lett ; 107(24): 241801, 2011 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-22242990

RESUMO

We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement.

12.
Phys Rev Lett ; 97(17): 171801, 2006 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-17155460

RESUMO

A search for the appearance of tau neutrinos from nu(mu) <--> nu(tau) oscillations in the atmospheric neutrinos has been performed using 1489.2 days of atmospheric neutrino data from the Super-Kamiokande-I experiment. A best fit tau neutrino appearance signal of 138+/-48(stat)-32(+15)(syst) events is obtained with an expectation of 78+/-26(syst). The hypothesis of no tau neutrino appearance is disfavored by 2.4 sigma.

13.
Phys Rev Lett ; 93(10): 101801, 2004 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-15447395

RESUMO

Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3)0.90 at 90% confidence level.

14.
Phys Rev Lett ; 93(2): 021802, 2004 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-15323899

RESUMO

A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)

15.
Phys Rev Lett ; 90(17): 171302, 2003 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12786067

RESUMO

We present the results of a search for low energy nu(e) from the Sun using 1496 days of data from Super-Kamiokande-I. We observe no significant excess of events and set an upper limit for the conversion probability to nu(e) of the 8B solar neutrino. This conversion limit is 0.8% (90% C.L.) of the standard solar model's neutrino flux for total energy=8-20 MeV. We also set a flux limit for monochromatic nu(e) for E(nu(e))=10-17 MeV.

16.
Phys Rev Lett ; 90(6): 061101, 2003 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-12633283

RESUMO

A search for the relic neutrinos from all past core-collapse supernovae was conducted using 1496 days of data from the Super-Kamiokande detector. This analysis looked for electron-type antineutrinos that had produced a positron with an energy greater than 18 MeV. In the absence of a signal, 90% C.L. upper limits on the total flux were set for several theoretical models; these limits ranged from 20 to 130 macro nu(e) cm(-2) s(-1). Additionally, an upper bound of 1.2 macro nu(e) cm(-2) s(-1) was set for the supernova relic neutrino flux in the energy region E(nu)>19.3 MeV.

17.
Surg Endosc ; 17(5): 711-5, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12616395

RESUMO

BACKGROUND: Because of the lack of evidence-based data comparing different techniques for thymectomy (Thx), a matched-pair study was conducted to evaluate the role of thoracoscopic Thx (tThx) more objectively. METHODS: Of 182 patients who underwent Thx, 3 groups according to the operation technique were matched for myasthenia gravis (MG) without thymoma, age, gender, and severity of MG. Twenty patients each who had Thx through anterolateral thoracotomy (aThx), extended median sternotomy (sThx), and tThx were compared for length of operation, postoperative morbidity, complete remission, quantification of improvement of MG, and cosmetic results. RESULTS: Complete tThx required 197 +/- 35 min as compared to 113 +/- 43 min for sThx and 82 +/- 27 min for aThx (P <0.001). With zero mortality the overall postoperative morbidity rate was 25% for sThx versus 15% for aThx and 5% for tThx (P <0.05). There was no difference in complete remission of MG. The median activities of daily living (ADL) scores improved by 6.0 (1-19) after tThx, 5.5 (2-4) after sThx, and 7.5 (0-12) after aThx. Best cosmetic results were achieved after tThx. CONCLUSIONS: There was adequate cumulative medium-term improvement of MG and less postoperative morbidity after tThx, which may become the preferred technique for Thx.


Assuntos
Miastenia Gravis/cirurgia , Timectomia/métodos , Adulto , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Análise por Pareamento , Miastenia Gravis/complicações , Estudos Retrospectivos , Índice de Gravidade de Doença , Toracoscopia/efeitos adversos , Toracoscopia/métodos , Timectomia/efeitos adversos , Timoma/patologia
18.
Phys Rev Lett ; 86(25): 5651-5, 2001 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-11415325

RESUMO

Solar neutrino measurements from 1258 days of data from the Super-Kamiokande detector are presented. The measurements are based on recoil electrons in the energy range 5.0-20.0 MeV. The measured solar neutrino flux is 2.32+/-0.03(stat)+0.08-0.07(syst)x10(6) cm(-2) x s(-1), which is 45.1+/-0.5(stat)+1.6-1.4(syst)% of that predicted by the BP2000 SSM. The day vs night flux asymmetry (Phi(n)-Phi(d))/Phi(average) is 0.033+/-0.022(stat)+0.013-0.012(syst). The recoil electron energy spectrum is consistent with no spectral distortion. For the hep neutrino flux, we set a 90% C.L. upper limit of 40x10(3) cm(-2) x s(-1), which is 4.3 times the BP2000 SSM prediction.

19.
Phys Rev Lett ; 86(25): 5656-60, 2001 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-11415326

RESUMO

We report the result of a search for neutrino oscillations using precise measurements of the recoil electron energy spectrum and zenith angle variations of the solar neutrino flux from 1258 days of neutrino-electron scattering data in Super-Kamiokande. The absence of significant zenith angle variation and spectrum distortion places strong constraints on neutrino mixing and mass difference in a flux-independent way. Using the Super-Kamiokande flux measurement in addition, two allowed regions at large mixing are found.

20.
Phys Rev Lett ; 85(19): 3999-4003, 2000 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11056609

RESUMO

The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau neutrinos or sterile neutrinos, as both hypotheses fit the data. Using data recorded in 1100 live days of the Super-Kamiokande detector, we use three complementary data samples to study the difference in zenith angle distribution due to neutral currents and matter effects. We find no evidence favoring sterile neutrinos, and reject the hypothesis at the 99% confidence level. On the other hand, we find that oscillation between muon and tau neutrinos suffices to explain all the results in hand.

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