Population genomics and connectivity of Vazella pourtalesii sponge grounds of the northwest Atlantic with conservation implications of deep sea vulnerable marine ecosystems.

Sponges are key ecosystem engineers that shape, structure and enhance the biodiversity of marine benthic communities globally. Sponge aggregations and reefs are recognized as vulnerable marine ecosystems (or VMEs) due to their susceptibility to damage from bottom-contact fishing gears. Ensuring their long-term sustainability, preservation, and ecosystem functions requires the implementation of sound scientific conservation tools.

Putative past, present, and future spatial distributions of deep-sea coral and sponge microbiomes revealed by predictive models.

Knowledge of spatial distribution patterns of biodiversity is key to evaluate and ensure ocean integrity and resilience. Especially for the deep ocean, where in situ monitoring requires sophisticated instruments and considerable financial investments, modeling approaches are crucial to move from scattered data points to predictive continuous maps. Those modeling approaches are commonly run on the macrobial level, but spatio-temporal predictions of host-associated microbiomes are not being targeted.

Reversible Capture Mechanism of CO as a Zn(II)-Methylcarbonate.

In this study, we elucidate the reaction mechanism for capturing CO with the ZnL(MeOH) complex (L=diacetyl-2-(4-methyl-3-thiosemicarbazone)-3-(2-hydrazinatopyridine)) in a methanol solution, using density functional theory calculations. One pathway involves the protonation of ZnL(MeOH) by methylcarbonic acid, followed by ligand exchange of MeOH with MeOCO . An alternative mechanism suggests a tautomerization between ZnL(MeOH) and Zn(HL)(OMe), followed by CO insertion.

Breaking the plane: BH is a three-dimensional structure.

In this study, we delved into the structure of BH and questioned some of its accepted assumptions. By exploring the potential energy surface, we found a new three-dimensional structure as the global minimum. This finding is in contrast with the previously hypothesized planar and cage-like models.

Unveiling the electronic and structural consequences of removing two electrons from BH.

The notion that a regular icosahedron is unattainable in neutral BH has persisted for nearly 70 years. This is because 24 valence electrons are used for B-H bonds, while another 24 electrons are necessary to maintain the deltahedron, unlike the 26 used in the dianion. According to Wade-Mingos rules, the neutral system should be a deltahedron with a capped face.

Hiatal hernia repair with biosynthetic mesh reinforcement: a qualitative systematic review.

Introduction: Reinforcement of crural closure with synthetic resorbable mesh has been proposed to decrease recurrence rates after hiatal hernia repair, but continues to be controversial. This systematic review aims to evaluate the safety, efficacy, and intermediate-term results of using biosynthetic mesh to augment the hiatus.

Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed throughout this systematic review.

Causal inference indicates that poor responders have similar outcomes with the antagonist protocol compared with flare.

Objective: To use causal inference to investigate whether the flare or antagonist protocol is better for poor responders going through controlled ovarian stimulation.

Design: A retrospective study.

Setting: Retrieval cycles from the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System.

Bacillary Layer Detachment in an Atypical Case of Central Serous Chorioretinopathy Associated with High Hyperopia.

A 16-year-old boy with elevated hyperopia presented to the office with a 24-h history of bilateral blurred vision, mainly of the left eye, and bilateral central serous chorioretinopathy. He showed a clinically recognizable bacillary layer detachment in one eye and excellent multimodal diagnostic image correlation, with the best-corrected visual acuity as 20/400. He had bilateral serous retinal detachment, as confirmed by optical coherence tomography.

Association of healthcare system factors with childhood leukemia mortality in Peru, 2017-2019: A population-based analysis.

Background: Childhood leukemia mortality is expected to increase in certain developing Latin American countries by 2030. The development of tailored public health interventions could benefit by understanding the role of healthcare system factors. Therefore, we aimed to evaluate the area-level association of healthcare system factors with leukemia mortality among Peruvian children aged 0-19.

Microwave-enhanced synthesis of 26-amino-22-oxocholestanes and their cytotoxic activity.

The synthesis of a series of 26-amino-22-oxocholestanes derived from diosgenin was accomplished via the substitution of an iodine atom at C-26 by primary and secondary amines. The reactions were conducted in refluxing acetonitrile and through microwave-assisted heating. The latter shows significant improvements in terms of reaction times going from hours to a few minutes or even seconds for completion.

Preferential habitats prediction in syngnathids using species distribution models.

Syngnathids are considered as flagship species for marine conservation. Seahorses and pipefish are highly vulnerable to anthropogenic and environmental disturbances, but most species are currently considered Data Deficient by IUCN, requiring more biological and ecological research. Although syngnathids are well known for their unusual breeding biology, some aspects on the ecology of this family have rarely received attention.

-Hydroboration-oxidation products in Δ-steroids a hydroboration--hydroboration mechanism.

Herein, we report for the first time a "-hydroboration-oxidation product" isolated and characterized under traditional hydroboration-oxidation conditions using cholesterol and diosgenin as substrates. These substrates are excellent starting materials because of the rigidity and different structural environments around the double bond. Further investigations based on experimental evidence, in conjunction with theoretical studies, indicate that the formation of this -species occurs a -hydroboration of the major product to generate the corresponding Δ-structure and the subsequent hydroboration by the β-face.

The curriculum of the plague.

The Covid-19 pandemic can be read as an eruption of the Real: a traumatic event that overwhelms our capacity for symbolization and exposes the fragility of the imaginary. Albert Camus addresses this traumatic dimension in his 1947 novel in which he reserves a rather puzzling statement for the closing paragraph: A plague never disappears, he wrote, but can lie dormant only to reappear once again "for the education of men". What lessons can be learned from the pandemic we are experiencing right now? While Covid-19 is often discussed from a biological perspective, the magnitude of the tragedy raises questions far beyond the confines of the natural/medical sciences, questions about humanity, our limits and possibilities, and the transcendent.

SARS-CoV-2 Infection with Associated Rhabdomyolysis and Probable Myocarditis.

Unlabelled: We describe a patient with SARS-CoV-2 and severe pneumonia who required mechanical ventilation and developed associated rhabdomyolysis with probable myocardial involvement as evidenced by cardiac enzyme abnormalities and echocardiographic findings. Repeat testing should be done in cases highly suspicious for SARS-CoV-2 as initial molecular tests may be negative, as in our case.

Learning Points: SARS-CoV-2 infection may be associated with rhabdomyolysis and myocarditis.

Author Correction: Removal of deep-sea sponges by bottom trawling in the Flemish Cap area: conservation, ecology and economic assessment.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Climate-induced changes in the suitable habitat of cold-water corals and commercially important deep-sea fishes in the North Atlantic.

The deep sea plays a critical role in global climate regulation through uptake and storage of heat and carbon dioxide. However, this regulating service causes warming, acidification and deoxygenation of deep waters, leading to decreased food availability at the seafloor. These changes and their projections are likely to affect productivity, biodiversity and distributions of deep-sea fauna, thereby compromising key ecosystem services.

Removal of deep-sea sponges by bottom trawling in the Flemish Cap area: conservation, ecology and economic assessment.

Deep-sea sponge grounds are vulnerable marine ecosystems, which through their benthic-pelagic coupling of nutrients, are of functional relevance to the deep-sea realm. The impact of fishing bycatch is here evaluated for the first time at a bathyal, sponge-dominated ecosystem in the high seas managed by the Northwest Atlantic Fisheries Organization. Sponge biomass surfaces created from research survey data using both random forest modeling and a gridded surface revealed 231,140 t of sponges in the area.

Origin of the isotropic motion in crystalline molecular rotors with carbazole stators.

Herein we report two crystalline molecular rotors and that show extremely narrow signals in deuterium solid-state NMR spectroscopy. Although this line shape is typically associated with fast-moving molecular components, our VT H NMR experiments, along with X-ray diffraction analyses and periodic DFT computations show that this spectroscopic feature can also be originated from low-frequency intramolecular rotations of the central phenylene with a cone angle of 54.7° that is attained by the cooperative motion of the entire structure that distorts the molecular axis to rotation.

Predicted distribution of the glass sponge Vazella pourtalesi on the Scotian Shelf and its persistence in the face of climatic variability.

Emerald Basin on the Scotian Shelf off Nova Scotia, Canada, is home to a globally unique aggregation of the glass sponge Vazella pourtalesi, first documented in the region in 1889. In 2009, Fisheries and Oceans Canada (DFO) implemented two Sponge Conservation Areas to protect these sponge grounds from bottom fishing activities. Together, the two conservation areas encompass 259 km2.

Revisiting the Formation Mechanism of 1,3,4-Oxadiazole-2(3 H)-ones from Hydrazonyl Chloride and Carbon Dioxide.

The reaction mechanism for the synthesis of 1,3,4-oxadiazole-2(3 H)-ones from hydrazonyl chloride and CO in the presence of CsF/18-crown-6 and toluene, is revisited via density functional theory computations. Although this reaction was earlier classified as a 1,3-dipolar cycloaddition, we found some competing pathways involved therein. The mechanisms including the (F-CO) anion and the nitrile imine intermediate are some options.

Bonding and Mobility of Alkali Metals in Helicenes.

In this work, we analyze the interactions of alkali metal cations with [6]- and [14]helicene and the cation mobility of therein. We found that the distortion of the carbon skeleton is the reason that some of the structures which are local minima for the smallest cations are not energetically stable for K , Rb , and Cs . Also, the most favorable complexes are those where the cation is interacting with two rings forming a metallocene-like structure, except for the largest cation Cs , where the distortion provoked by the size of the cation destabilizes the complex.

Revisiting the racemization mechanism of helicenes.

Herein we propose a general mechanism for the racemization of [n]helicenes up to n = 24. It is a concerted process for n = 4-7, but a multi-step mechanism is followed for n≥ 8, involving 2n- 14 intermediates. The changes in the barriers are a delicate consequence of the steric hindrance and the π-interactions.

Does HSO exist?

The possible existence of HSO in aqueous sulfuric acid is analyzed in detail. For bare HSO, the computed free energy barrier for the exergonic transformation of HSO into the HSOHO complex is only 3.8 kcal mol.