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We have used neutron diffraction to observe the vortex lattice of UPt3. This is the first such measurement in a heavy-fermion system, a superconductor below 1 K, or in a system with such a long magnetic penetration depth (6000 ± 75 A). It also provides the first value for the pair coherence length, 111 ± 2 A, to be obtained directly within the pairing state of UPta. The lattice is oblique hexagonal with conventional quantization. Its anisotropy can be explained by considering a combination of gap and Fermisurface anisotropics. The lattice does not appear to change near the transitions between the superconducting phases identified by other techniques.PACS numbers: 74.70.Tx, 61.12.Bt, 74.60.GeThere is considerable indirect evidence that the heavyfermion material UPts is not a conventional 5-wave superconductor [l]. This evidence consists primarily of the observation of power-law, rather than exponential, behavior in its thermal and transport properties. Transverse ultrasound [2] and muon spin relaxation (ju'*'SR) measurements [3] show diiTerent power laws for diff"erent crystalline directions in a manner consistent with the E\g symmetry [4]. Further indications of higher-/ pairing lie in torsional oscillator [5], ultrasound [6], and specific-heat measurements [7] which show evidence for possible phase transitions within the superconducting state. At r=0 ultrasound anomalies occur [8] when //^ 0.65//^ 2 (Hllc) and H^0.25Hc2(H±c). Since the transition occurs as a function of magnetic field, i.e., vortex density, and the probes observing it are sensitive to vortex motion, it is natural to suggest [9] that this transition corresponds to changes in the vortex lattice at this field. Because of this and the possibility that the unconventional superconducting state manifests itself directly in the vortex lattice, we have used neutron diffraction to study the vortex lattice in UPt3.Our sample is a right circular cylinder ^ 5 mm in diameter and 30 mm long oriented with c along the cylinder axis. The boule was Czochralski grown and float zone purified, and then annealed in vacuum for 150 h at 1300°C and cooled slowly to room temperature. The extrapolated r=0 resistivity along the a axis was 1.3 /iHcm, equivalent to a mean free path /-1700 A, and the superconducting transition in zero field was clearly split (from specific-heat measurement [10]), with Tc~ = 0.451 and r/=0.507 K.Neutron scattering from the vortex lattice was first suggested by de Gennes and Matricon [11], first measured in niobium by Cribier et al. [12], and subsequently observed in a number of cubic materials [13][14][15], in technetium [15], and in YBa2Cu307 [16]. Our experiment was performed using the small-angle neutron scattering (SANS) apparatus in the cold-neutron guide hall of the Ris

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The 91-day extended-regimen COC with low-dose EE supplementation was found to be effective in suppressing ovarian activity and inhibiting ovulation and was well tolerated. Return to ovulation was rapid, occurring within approximately one month after discontinuation of COC.

Objective The objective was to evaluate the contraceptive effectiveness, safety, and acceptability of a novel vaginal pH regulator over seven cycles of use. Study design A single-arm, open-label, phase 3 study was conducted across 112 sites in the United States in sexually active 18–35-year-old women at risk of pregnancy. Women administered the study treatment ≤ 1 h before each episode of intercourse. Women recorded use of study drug, coital information, and any symptoms experienced in electronic diaries. The primary outcome was the seven-cycle cumulative pregnancy rate as calculated using the Kaplan–Meier methodology; secondary outcomes included safety. Overall satisfaction was assessed via written questionnaires. Results A total of 1384 women were enrolled in the study from July 2017 to November 2018. Mean age was 27.7 ± 4.4 years; most women were white (69.0%). The seven-cycle cumulative pregnancy percentage was 13.7% [95% confidence interval (CI): 10.0%–17.5%], meeting the prespecified primary endpoint of having the upper bound 95% CI ≤ 21%. Most common adverse events (AEs) occurring in ≥ 2% of women were vulvovaginal burning sensation, vulvovaginal pruritus, urinary tract infection, vulvovaginal pain, mycotic infection, bacterial vaginosis, and nasopharyngitis. Of 1330 women who used the study drug at least once, fewer than 2% of women discontinued due to any AEs, and < 1% of women discontinued due to genitourinary symptoms. Overall, > 80% of women reported being “very satisfied” or “satisfied” with study treatment. Conclusions In this phase 3 study, the novel vaginal pH regulator demonstrated 86.3% contraceptive effectiveness, was safe and well tolerated, and was highly acceptable. Implications This novel vaginal pH regulator is a safe, nonhormonal, woman-controlled method of contraception that expands women's options.