We observe the suppression of the 1D transport of an interacting elongated Bose-Einstein condensate in a random potential with an amplitude that is small compared to the typical energy per atom, ...dominated by the interaction energy. Numerical calculations reproduce our observations well. We propose a scenario for disorder-induced trapping of the condensate in agreement with our findings.
Background and Aims Pterostylisis an Australasian terrestrial orchid genus of more than 400 species, most of which use a motile, touch-sensitive labellum to trap dipteran pollinators. Despite studies ...dating back to 1872, the mechanism of pollinator attraction has remained elusive. This study tested whether the fungus gnat-pollinated Pterostylis sanguinea secures pollination by sexual deception.MethodsThe literature was used to establish criteria for confirming sexual deception as a pollination strategy. Observations and video recordings allowed quantification of each step of the pollination process. Each floral visitor was sexed and DNA barcoding was used to evaluate the degree of pollinator specificity. Following observations that attraction to the flowers is by chemical cues, experimental dissection of flowers was used to determine the source of the sexual attractant and the effect of labellum orientation on sexual attraction. Fruit set was quantified for 19 populations to test for a relationship with plant density and population size.Key ResultsA single species of male gnat (Mycetophilidae) visited and pollinated the rewardless flowers. The gnats often showed probing copulatory behaviour on the labellum, leading to its triggering and the temporary entrapment of the gnat in the flower. Pollen deposition and removal occurred as the gnat escaped from the flower via the reproductive structures. The labellum was the sole source of the chemical attractant. Gnats always alighted on the labellum facing upwards, but when it was rotated 180 ° they attempted copulation less frequently. Pollination rate showed no relationship with orchid population size or plant density.ConclusionsThis study confirms for the first time that highly specific pollination by fungus gnats is achieved by sexual deception in Pterostylis. It is predicted that sexual deception will be widespread in the genus, although the diversity of floral forms suggests that other mechanisms may also operate.
We present a detailed analysis of the 1D expansion of a coherent interacting matterwave (a Bose-Einstein condensate) in the presence of disorder. A 1D random potential is created via laser speckle ...patterns. It is carefully calibrated and the self-averaging properties of our experimental system are discussed. We observe the suppression of the transport of the BEC in the random potential. We discuss the scenario of disorder-induced trapping taking into account the radial extension in our experimental 3D BEC and we compare our experimental results with the theoretical predictions.
Abstract Background Comparative studies on the use of meshes and acellular dermal matrices (ADM) in implant-based breast reconstruction (IBBR) have not yet been performed. Methods This prospective, ...randomized, controlled, multicenter pilot study was performed at four Austrian breast cancer centers. Fifty patients with oncologic or prophylactic indication for mastectomy and IBBR were randomized to immediate IBBR with either an ADM (Protexa® ) or a titanized mesh (TiLOOP® Bra). Complications, failed reconstruction, cosmetic outcome, patients' quality of life and the thickness of the overlying tissue were recorded immediately postoperatively and 3 and 6 months after surgery. Results 48 patients participated in the study (Protexa® group: 23; TiLOOP® Bra group: 25 patients). The overall complication rate was 31.25% with similar rates in both groups (Protexa® group: 9 versus TiLOOP® Bra group: 6; p = 0.188). There was a higher incidence of severe complications leading to failed reconstructions with implant loss in the Protexa® group than in the TiLOOP® Bra group (7 versus 2; p < 0.0001). An inverted T-incision technique led to significantly more complications and reconstructive failure with Protexa® (p = 0.037, p = 0.012, respectively). There were no significant differences in patients' satisfaction with cosmetic results (p = 0.632), but surgeons and external specialists graded significantly better outcomes with TiLOOP® Bra (p = 0.034, p = 0.032). Conclusion This pilot study showed use of TiLOOP® Bra or Protexa® in IBBR is feasible leading to good cosmetic outcomes and high patient satisfaction. To validate the higher failure rates in the Protexa® group, data from a larger trial are required. NCT02562170
To evaluate the incidence of pulmonary ischaemia in COVID-19 patients on extracorporeal membrane oxygenation (ECMO), and its correlation with pulmonary artery thrombosis.
Computed tomography (CT) ...thorax of all patients receiving ECMO with proven COVID-19 pneumonitis between March and May 2020 were analysed for the presence and extension of pulmonary thromboembolic disease.
Fifty-one patients were reviewed. The mean (range) age of 45 (26–66) years; 38/51 (74.5%) were men. All patients had severe COVID-19 pneumonitis, and 18/51 (35.3%) had macroscopic thrombosis (15 with associated ischaemia); however, 13/51 (25.5%) patients had ischaemia without associated thrombus.
The majority of patients with COVID-19 who received ECMO had areas of ischaemia within consolidated lungs, almost half of these without subtending pulmonary artery thrombosis. Although the prognostic significance of these findings is unclear, they are highly suggestive of lung ischaemia due to isolated microvascular immune thrombosis.
•High incidence of pulmonary artery thrombosis in COVID-19 ECMO patients.•Lung ischaemia seen in patients with and without visible pulmonary artery thrombus.•Ischaemia with no visible thrombus suggest microvascular thrombosis.
Summary
The aetiology and management of haemostatic abnormalities in critical care patients are considered in this narrative review. The mechanisms of normal haemostasis and derangements that occur ...as a result of sepsis and organ dysfunction are discussed. Finally, the management of haemostatic abnormalities as they relate to critical care practice are considered, including the management of heparin‐induced thrombocytopenia.
Untreated hereditary antithrombin deficiency in pregnancy is associated with maternal venous thromboembolism (VTE) and possibly with fetal loss. Thromboprophylaxis during pregnancy is recommended, ...but dosages remain controversial.Our objective was to perform a retrospective assessment of thrombotic events and pregnancy outcomes in women with hereditary antithrombin deficiency managed according to a standard protocol. Pregnancies in individuals with hereditary antithrombin deficiency were identified from a hospital database. Women with no prior VTE received enoxaparin 40 mg daily until 16 weeks gestation and thereafter 40 mg twice daily. Women with prior VTE received intermediate dose enoxaparin (1 mg/kg) once daily, increased to twice daily at 16 weeks and anti-Xa monitored dosing. Thromboprophylaxis was stopped at initiation of labour or 12 hours prior to caesarean and 50 IU/kg antithrombin concentrate given. Thromboprophylaxis was restarted after delivery. Eighteen pregnancies in 11 women with antithrombin deficiency were identified. Seventeen pregnancies (94%) were successful. Median gestation was 39 weeks (range 30–41) and median birth-weight was 2,995 g (910–4,120 g), but 6/17 infants (35%) were small for gestational age (p=0.01). Estimated blood loss at delivery was median 375 ml (200–600 ml). Four pregnancies were complicated by VTE; one newly presented with a thrombotic event, two patients were not taking thromboprophylaxis and one occurred despite thromboprophylaxis. Two novel mutations (p.Leu317Ser and p.His33GInfsX32) are described. In conclusion, in antithrombin deficiency the use of low-molecular-weight heparin in pregnancy and puerperium with antithrombin concentrate pre-delivery was associated with successful pregnancy outcome; rates of VTE appear to be lower than previously reported, but remain elevated.
Objective Aromatase inhibitors are essential as endocrine treatment for hormone receptor-positive postmenopausal breast cancer patients. Menopausal symptoms are often aggravated during endocrine ...treatment. We investigated whether vaginal estriol is a safe therapeutic option to overcome the urogenital side-effects of aromatase inhibitors. Serum hormone levels were used as the surrogate parameter for safety.
Methods Fasting serum hormone levels of ten postmenopausal breast cancer patients receiving aromatase inhibitors were prospectively measured by electro-chemiluminescence immunoassays and gas chromatography/mass spectrometry before and 2 weeks after daily application of 0.5 mg vaginal estriol (Ovestin® ovula), respectively.
Results Two weeks of daily vaginal estriol treatment did not change serum estradiol or estriol levels. However, significant decreases in levels of serum follicle stimulating hormone (p = 0.01) and luteinizing hormone (p = 0.02) were observed. Five out of six breast cancer patients noticed an improvement in vaginal dryness and/or dyspareunia.
Conclusions The significant decline in gonadotropin levels, indicating systemic effects, has to be kept in mind when offering vaginal estriol to breast cancer patients receiving an aromatase inhibitor.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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