The Formation Rate of Blue Stragglers in 47 Tucanae

We investigate the effects of changes in the blue straggler formation rate in globular clusters on the blue straggler distribution in the color-magnitude diagram. We find that the blue straggler distribution is highly sensitive to the past formation rate. Comparing our models to new UBV observations of a region close to the core of 47 Tucanae suggests that this cluster may have stopped forming blue straggler formation several Gyr ago. This cessation of formation can be associated with an epoch of primordial binary burning which has been invoked in other clusters to infer the imminence of core collapse.Comment: 17 pages, 9 figures, submitted to the Astrophysical Journa

Follow-up analysis of federal process of care data reported from three acute care hospitals in rural Appalachia

BACKGROUND: This investigation evaluated standardized process of care data collected on selected hospitals serving a remote rural section of westernmost North Carolina. METHODS: Centers for Medicare and Medicaid Services data were analyzed retrospectively for multiple clinical parameters at Fannin Regional Hospital, Murphy Medical Center, and Union General Hospital. Data were analyzed by paired t-test for individual comparisons among the three study hospitals to compare the three facilities with each other, as well as with state and national average for each parameter. RESULTS: Centers for Medicare and Medicaid Services "Hospital Compare" data from 2011 showed Fannin Regional Hospital to have significantly higher composite scores on standardized clinical process of care measures relative to the national average, compared with Murphy Medical Center (P = 0.01) and Union General Hospital (P = 0.01). This difference was noted to persist when Fannin Regional Hospital was compared with Union General Hospital using common state reference data (P = 0.02). When compared with national averages, mean process of care scores reported from Murphy Medical Center and Union General Hospital were both lower but not significantly different (-3.44 versus -6.07, respectively, P = 0.54). CONCLUSION: The range of process of care scores submitted by acute care hospitals in western North Carolina is considerable. Centers for Medicare and Medicaid Services "Hospital Compare" information suggests that process of care measurements at Fannin Regional Hospital are significantly higher than at either Murphy Medical Center or Union General Hospital, relative to state and national benchmarks. Further investigation is needed to determine what impact these differences in process of care may have on hospital volume and/or market share in this region. Additional research is planned to identify process of care trends in this demographic and geographically rural area

Intrauterine pregnancy following low-dose gonadotropin ovulation induction and direct intraperitoneal insemination for severe cervical stenosis

BACKGROUND: We present a case of primary infertility related to extreme cervical stenosis, a subset of cervical factor infertility which accounts for approximately 5% of all clinical infertility referrals. CASE PRESENTATION: A 37 year-old nulligravida was successfully treated with ovulation induction via recombinant follicle stimulating hormone (FSH) and direct intraperitoneal insemination (IPI). Anticipating controlled ovarian hyperstimulation with in vitro fertilization/embryo transfer (IVF), the patient underwent hysteroscopy and cervical recanalization, but safe intrauterine access was not possible due to severe proximal cervical stricture. Hysterosalpingogram established bilateral tubal patency and confirmed an irregular cervical contour. Since the cervical canal could not be traversed, neither standard intrauterine insemination nor transcervical embryo transfer could be offered. Prepared spermatozoa were therefore placed intraperitoneally at both tubal fimbria under real-time transvaginal sonographic guidance using a 17 gage single-lumen IVF needle. Supplementary progesterone was administered as 200 mg/d lozenge (troche) plus 200 mg/d rectal suppository, maintained from the day following IPI to the 8(th )gestational week. A singleton intrauterine pregnancy was achieved after the second ovulation induction attempt. CONCLUSIONS: In this report, we outline the relevance of cervical factor infertility to reproductive medicine practice. Additionally, our andrology evaluation, ovulation induction approach, spermatozoa preparation, and insemination technique in such cases are described

Models of Individual Blue Stragglers

This chapter describes the current state of models of individual blue stragglers. Stellar collisions, binary mergers (or coalescence), and partial or ongoing mass transfer have all been studied in some detail. The products of stellar collisions retain memory of their parent stars and are not fully mixed. Very high initial rotation rates must be reduced by an unknown process to allow the stars to collapse to the main sequence. The more massive collision products have shorter lifetimes than normal stars of the same mass, while products between low mass stars are long-lived and look very much like normal stars of their mass. Mass transfer can result in a merger, or can produce another binary system with a blue straggler and the remnant of the original primary. The products of binary mass transfer cover a larger portion of the colour-magnitude diagram than collision products for two reasons: there are more possible configurations which produce blue stragglers, and there are differing contributions to the blended light of the system. The effects of rotation may be substantial in both collision and merger products, and could result in significant mixing unless angular momentum is lost shortly after the formation event. Surface abundances may provide ways to distinguish between the formation mechanisms, but care must be taking to model the various mixing mechanisms properly before drawing strong conclusions. Avenues for future work are outlined.Comment: Chapter 12, in Ecology of Blue Straggler Stars, H.M.J. Boffin, G. Carraro & G. Beccari (Eds), Astrophysics and Space Science Library, Springe

Double Blue Straggler sequences in GCs: the case of NGC 362

We used high-quality images acquired with the WFC3 on board the HST to probe the blue straggler star (BSS) population of the Galactic globular cluster NGC 362. We have found two distinct sequences of BSS: this is the second case, after M 30, where such a feature has been observed. Indeed the BSS location, their extension in magnitude and color and their radial distribution within the cluster nicely resemble those observed in M 30, thus suggesting that the same interpretative scenario can be applied: the red BSS sub-population is generated by mass transfer binaries, the blue one by collisions. The discovery of four new W UMa stars, three of which lying along the red-BSS sequence, further supports this scenario. We also found that the inner portion of the density profile deviates from a King model and is well reproduced by either a mild power-law (\alpha -0.2) or a double King profile. This feature supports the hypothesis that the cluster is currently undergoing the core collapse phase. Moreover, the BSS radial distribution shows a central peak and monotonically decreases outward without any evidence of an external rising branch. This evidence is a further indication of the advanced dynamical age of NGC 362: in fact, together with M 30, NGC 362 belongs to the family of dynamically old clusters (Family III) in the "dynamical clock" classification proposed by Ferraro et al. (2012). The observational evidence presented here strengthens the possible connection between the existence of a double BSS sequence and a quite advanced dynamical status of the parent cluster.Comment: Accepted for publication by ApJ; 39 pages, 16 figures, 1 tabl

First Irish delivery following sequential, two-stage embryo and blastocyst transfer.

BACKGROUND: The timing of embryo transfer (ET) after in vitro fertilisation (IVF) remains controversial, and there are no reliable guidelines available to prospectively identify which patients would benefit from either day-3 or blastocyst transfer. While blastocyst transfer is generally favoured over day-3 transfers, very few IVF patients get both in the same treatment cycle. CASE DESCRIPTION: We report on a 35.5-year-old female with tubal factor infertility who underwent IVF, which included transfer of a fresh day-3 embryo and a thawed blastocyst frozen at day 6. Transfer occurred on two separate days (days 3 and 6) in a two-stage/dual catheter fashion and resulted in a healthy term singleton livebirth. CONCLUSIONS: While combined day-3 and day-5 ET has been available elsewhere for several years, this is the first description of its successful application in Ireland and confirms the effectiveness of coordinated two-stage transfer in a single IVF treatment cycle

Blastocyst transfer for multiple prior IVF failure: a five year descriptive study

Patients with recurrent IVF failure are generally regarded as having a poor prognosis, and when female age exceeds 35yrs such patients face a particularly bleak outlook. This study reported on blastocyst transfer (BT) performed over a five-year interval in patients seeking “second opinion” after multiple failed IVF cycles. Clinical features and reproductive outcomes were compared between two sets of poor-prognosis IVF patients undergoing BT for the first time, the initial group underwent treatment in 2002 (n=66) and a second group presented five years later (n=392). The two clinical sets had no patients in common. The 2002 group had an average of 3.5(±1.1) prior failed IVF cycles at baseline, and mean (±SD) patient age was 36.4(±3.9)yrs. Average number of oocytes retrieved in this group was 10.4(±5.3) with a fertilisation rate of 58.8%. Although embryo arrest resulted in no transfer for 19 patients (28.8%), clinical pregnancy was achieved for 59.6% of transfers. Five years later, 392 patients underwent BT, but this group had an average of 4.5(±2.3) prior failed IVF cycles. Mean (±SD) female age was 36.0(±3.9)yrs, and the average number of oocytes retrieved in this group was 9.1(±5.4); the fertilisation rate was 59.5%. No blastocysts were available for transfer in 99 cases (25.3%); clinical pregnancy was achieved for 50.0% of transfers. The number of blastocysts transferred was similar in the two groups (1.6 vs. 1.3; p=0.06); the twinning rate rose slightly from 8.2% to 15.1% (p=0.12) despite an increased utilisation of single embryo transfer in 2007 (19.7% vs. 22.2%; p=0.40). Comparisons from 2002 and 2007 found no important differences between the two patient groups, except for a significantly higher rate of prior failed cycles in the 2007 group (

The evolution of health policy guidelines for assisted reproduction in the Republic of Ireland, 2004-2009

This analysis reports on Irish regulatory policies for in vitro fertilisation (IVF) from 2004-2009, in the context of membership changes within the Medical Council of Ireland. To achieve this, the current (2009) edition of the Guide to Professional Conduct & Ethics was compared with the immediately preceding version (2004). The statutory composition of the Medical Council from 2004-2009 was also studied. Content analysis of the two editions identified the following differences: 1) The 2004 guide states that IVF "should only be used after thorough investigation has failed to reveal a treatable cause of the infertility", while the 2009 guide indicates IVF "should only be used after thorough investigation has shown that no other treatment is likely to be effective"; 2) The 2004 stipulation stating that fertilized ovum (embryo) "must be used for normal implantation and must not be deliberately destroyed" is absent from the 2009 guidelines; 3) The option to donate "unused fertilised ova" (embryos) is omitted from the 2009 guidelines; 4) The 2009 guidelines state that ART should be offered only by "suitably qualified professionals, in appropriate facilities, and according to the international best practice"; 5) The 2009 guidelines introduce criteria that donations as part of a donor programme should be "altruistic and non-commercial". These last two points represent original regulatory efforts not appearing in the 2004 edition. The Medical Practitioners Act 2007 reduced the number of physicians on the Medical Council to 6 (of 25) members. The ethical guidelines from 2004 preceded this change, while the reconstituted Medical Council published the 2009 version. Between 2004 and 2009, substantial modifications in reproductive health policy were incorporated into the Medical Council's ethical guidelines. The absence of controlling Irish legislation means that patients and IVF providers in Ireland must rely upon these guidelines by default. Our critique traces the evolution of public policy on IVF during a time when the membership of the Medical Council changed radically; reduced physician contribution to decision-making was associated with diminished protection for IVF-derived embryos in Ireland. Considerable uncertainty on IVF practice in Ireland remains

The ACS LCID project VII: the blue stragglers population in the isolated dSph galaxies Cetus and Tucana

We present the first investigation of the Blue Straggler star (BSS) population in two isolated dwarf spheroidal galaxies of the Local Group, Cetus and Tucana. Deep HST/ACS photometry allowed us to identify samples of 940 and 1214 candidates, respectively. The analysis of the star formation histories of the two galaxies suggests that both host a population of BSSs. Specifically, if the BSS candidates are interpreted as young main sequence stars, they do not conform to their galaxy's age-metallicity relationship. The analysis of the luminosity function and the radial distributions support this conclusion, and suggest a non-collisional mechanism for the BSS formation, from the evolution of primordial binaries. This scenario is also supported by the results of new dynamical simulations presented here. Both galaxies coincide with the relationship between the BSS frequency and the absolute visual magnitude Mv found by Momany et al (2007). If this relationship is confirmed by larger sample, then it could be a valuable tool to discriminate between the presence of BSSs and galaxies hosting truly young populations.Comment: Accepted for publication on ApJ. 15 pages, 3 tables, 13 figures. A version with high resolution figure can be downloaded from http://rialto.ll.iac.es/proyecto/LCID/?p=publication