Notes on the milliped Pleuroloma flavipes (Polydesmida: Xystodesmidae) in Wisconsin

The milliped Pleuroloma flavipes Rafinesque 1820 is one of the more widespread and better known North American millipeds. During the course of recent studies in Wisconsin, we have had opportunities to examine museum specimens and make field observations of this species. In this note, we report new locality records, discuss observations of mass aggregations, describe a color variation, and illustrate an individual with developmental abnormalities

Thalassiosira spp. Community Composition Shifts in Response to Chemical and Physical Forcing in the Northeast Pacific Ocean

Diatoms are genetically diverse unicellular photosynthetic eukaryotes that are key primary producers in the ocean. Many of the over 100 extant diatom species in the cosmopolitan genus Thalassiosira are difficult to distinguish in mixed populations using light microscopy. Here, we examine shifts in Thalassiosira spp. composition along a coastal to open ocean transect that encountered a 3-month-old Haida eddy in the northeast Pacific Ocean. To quantify shifts in Thalassiosira species composition, we developed a targeted automated ribosomal intergenic spacer analysis (ARISA) method to identify Thalassiosira spp. in environmental samples. As many specific fragment lengths are indicative of individual Thalassiosira spp., the ARISA method is a useful screening tool to identify changes in the relative abundance and distribution of specific species. The method also enabled us to assess changes in Thalassiosira community composition in response to chemical and physical forcing. Thalassiosira spp. community composition in the core of a 3-month-old Haida eddy remained largely (\u3e80%) similar over a 2-week period, despite moving 24 km southwestward. Shifts in Thalassiosira species correlated with changes in dissolved iron (Fe) and temperature throughout the sampling period. Simultaneously tracking community composition and relative abundance of Thalassiosira species within the physical and chemical context they occurred allowed us to identify quantitative linkages between environmental conditions and community response

\u3cem\u3eThalassiosira spp.\u3c/em\u3e Community Composition Shifts in Response to Chemical and Physical Forcing in the Northeast Pacific Ocean

Diatoms are genetically diverse unicellular photosynthetic eukaryotes that are key primary producers in the ocean. Many of the over 100 extant diatom species in the cosmopolitan genus Thalassiosira are difficult to distinguish in mixed populations using light microscopy. Here, we examine shifts in Thalassiosira spp. composition along a coastal to open ocean transect that encountered a 3-month-old Haida eddy in the northeast Pacific Ocean. To quantify shifts in Thalassiosira species composition, we developed a targeted automated ribosomal intergenic spacer analysis (ARISA) method to identify Thalassiosira spp. in environmental samples. As many specific fragment lengths are indicative of individual Thalassiosira spp., the ARISA method is a useful screening tool to identify changes in the relative abundance and distribution of specific species. The method also enabled us to assess changes in Thalassiosira community composition in response to chemical and physical forcing. Thalassiosira spp. community composition in the core of a 3-month-old Haida eddy remained largely (\u3e80%) similar over a 2-week period, despite moving 24 km southwestward. Shifts in Thalassiosira species correlated with changes in dissolved iron (Fe) and temperature throughout the sampling period. Simultaneously tracking community composition and relative abundance of Thalassiosira species within the physical and chemical context they occurred allowed us to identify quantitative linkages between environmental conditions and community response

Diatom hotspots driven by western boundary current instability

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 48(11), (2021): e2020GL091943, https://doi.org/10.1029/2020GL091943.Climatic changes have decreased the stability of the Gulf Stream (GS), increasing the frequency at which its meanders interact with the Mid-Atlantic Bight (MAB) continental shelf and slope region. These intrusions are thought to suppress biological productivity by transporting low-nutrient water to the otherwise productive shelf edge region. Here we present evidence of widespread, anomalously intense subsurface diatom hotspots in the MAB slope sea that likely resulted from a GS intrusion in July 2019. The hotspots (at ∼50 m) were associated with water mass properties characteristic of GS water (∼100 m); it is probable that the hotspots resulted from the upwelling of GS water during its transport into the slope sea, likely by a GS meander directly intruding onto the continental slope east of where the hotspots were observed. Further work is required to unravel how increasingly frequent direct GS intrusions could influence MAB marine ecosystems.This research was supported by the National Science Foundation (OCE-1657803 and OCE-1657855) and the Dalio Explorer Fund. H. Oliver was supported by a WHOI Postdoctoral Scholar award

Diatom Hotspots Driven by Western Boundary Current Instability

Abstract Climatic changes have decreased the stability of the Gulf Stream (GS), increasing the frequency at which its meanders interact with the Mid-Atlantic Bight (MAB) continental shelf and slope region. These intrusions are thought to suppress biological productivity by transporting low-nutrient water to the otherwise productive shelf edge region. Here we present evidence of widespread, anomalously intense subsurface diatom hotspots in the MAB slope sea that likely resulted from a GS intrusion in July 2019. The hotspots (at ∼50 m) were associated with water mass properties characteristic of GS water (∼100 m); it is probable that the hotspots resulted from the upwelling of GS water during its transport into the slope sea, likely by a GS meander directly intruding onto the continental slope east of where the hotspots were observed. Further work is required to unravel how increasingly frequent direct GS intrusions could influence MAB marine ecosystems

Réponse insuffisante à la stimulation en vue de FIV : maintenir la ponction ou choisir l' insémination ?

In women undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF), a poor ovarian response, defined as three of fewer mature follicles, can lead to cancellation of the cycle. However, in women with at least one patent tube and normal semen parameters, conversion to intrauterine insemination (IUI) is considered an option, offering reasonable pregnancy rates at a lower cost and without the complications associated with oocyte retrieval. Studies have shown that in cycles with only one mature follicle, IVF should be canceled. However, in cycles with 2 or 3 mature follicles, patients have the choice between IVF and conversion to IUI. Some studies have shown that IVF is superior to IUI in such cases, whereas other reports failed to find any difference. Most of these studies are retrospective and limited by the presence of several biases and low numbers of cycles, and to this date, there is no consensus on the best approach. We have thus designed a multicenter, randomized non-inferiority study, comparing live birth rates following conversion to IUI or IVF in patients with 2 or 3 mature follicles in COH cycles. Nine hundred and forty patients will be randomized on trigger day to either IVF or conversion to IUI. Our study will also include a medico-economic analysis

Surgical treatment of septate uterus in cases of primary infertility and before assisted reproductive technologies

Septate uterus is the most common congenital uterine malformation in women with infertility. Several criteria are available for the definition of septate uteri, such as the one proposed by the European Society of Human Reproduction and Embryology (ESHRE)/European Society for Gynecological Endoscopy (ESGE) (ESHRE/ESGE), or by the American Society for Reproductive Medicine (ASRM), with notable differences between the two. Recently, a simplified classification was proposed by the Congenital Uterine Malformations Experts (CUME), where a septum is defined as an internal indentation depth≥10mm. To date, there is no consensus on the management of women with a septate uterus and infertility. We have performed an extensive literature appraisal and reviewed all the available international guidelines in order to propose a management strategy for infertile patients with a uterine septum. Hysteroscopic septum incision seems to improve natural conception rates in the year following surgery. Moreover, it improves in vitro fertilization (IVF) outcomes when performed before the embryo transfer, by improving embryo implantation rates. On the other hand, for patients with an arcuate uterus (indentation<1.5cm according to the ASRM guidelines) and infertility, it seems that assisted reproductive technologies are the most appropriate first line treatment. However, in cases of recurrent implantation failure or recurrent pregnancy loss following IVF, hysteroscopic section could be proposed. Overall, we recommend hysteroscopic septum incision for patients with primary infertility, and for patients undergoing assisted reproductive technologies

Receptor Complementation and Mutagenesis Reveal SR-BI as an Essential HCV Entry Factor and Functionally Imply Its Intra- and Extra-Cellular Domains

HCV entry into cells is a multi-step and slow process. It is believed that the initial capture of HCV particles by glycosaminoglycans and/or lipoprotein receptors is followed by coordinated interactions with the scavenger receptor class B type I (SR-BI), a major receptor of high-density lipoprotein (HDL), the CD81 tetraspanin, and the tight junction protein Claudin-1, ultimately leading to uptake and cellular penetration of HCV via low-pH endosomes. Several reports have indicated that HDL promotes HCV entry through interaction with SR-BI. This pathway remains largely elusive, although it was shown that HDL neither associates with HCV particles nor modulates HCV binding to SR-BI. In contrast to CD81 and Claudin-1, the importance of SR-BI has only been addressed indirectly because of lack of cells in which functional complementation assays with mutant receptors could be performed. Here we identified for the first time two cell types that supported HCVpp and HCVcc entry upon ectopic SR-BI expression. Remarkably, the undetectable expression of SR-BI in rat hepatoma cells allowed unambiguous investigation of human SR-BI functions during HCV entry. By expressing different SR-BI mutants in either cell line, our results revealed features of SR-BI intracellular domains that influence HCV infectivity without affecting receptor binding and stimulation of HCV entry induced by HDL/SR-BI interaction. Conversely, we identified positions of SR-BI ectodomain that, by altering HCV binding, inhibit entry. Finally, we characterized alternative ectodomain determinants that, by reducing SR-BI cholesterol uptake and efflux functions, abolish HDL-mediated infection-enhancement. Altogether, we demonstrate that SR-BI is an essential HCV entry factor. Moreover, our results highlight specific SR-BI determinants required during HCV entry and physiological lipid transfer functions hijacked by HCV to favor infection