The proposed dropping of the genus crassostrea for all Pacific cupped oysters and its replacement by a new genus magallana: a dissenting view

The World Register of Marine Species (WoRMS) currently registers all Pacific cupped oysters that were formerly members of the genus Crassostrea in a new genus, Magallana. Magallana gigas is designated as an ‘‘accepted name,’’ whereas a search for Crassostrea gigas results in the message ‘‘no matching results found.’’ This has caused dismay among many biologists, aquaculturists, and other stakeholders with an interest in the Pacific and other oysters. This note, which is authored by 27 interested scientists, presents a dissenting view and a rebuttal of the proposed change of genus

Can biological quantum networks solve NP-hard problems?

There is a widespread view that the human brain is so complex that it cannot be efficiently simulated by universal Turing machines. During the last decades the question has therefore been raised whether we need to consider quantum effects to explain the imagined cognitive power of a conscious mind. This paper presents a personal view of several fields of philosophy and computational neurobiology in an attempt to suggest a realistic picture of how the brain might work as a basis for perception, consciousness and cognition. The purpose is to be able to identify and evaluate instances where quantum effects might play a significant role in cognitive processes. Not surprisingly, the conclusion is that quantum-enhanced cognition and intelligence are very unlikely to be found in biological brains. Quantum effects may certainly influence the functionality of various components and signalling pathways at the molecular level in the brain network, like ion ports, synapses, sensors, and enzymes. This might evidently influence the functionality of some nodes and perhaps even the overall intelligence of the brain network, but hardly give it any dramatically enhanced functionality. So, the conclusion is that biological quantum networks can only approximately solve small instances of NP-hard problems. On the other hand, artificial intelligence and machine learning implemented in complex dynamical systems based on genuine quantum networks can certainly be expected to show enhanced performance and quantum advantage compared with classical networks. Nevertheless, even quantum networks can only be expected to efficiently solve NP-hard problems approximately. In the end it is a question of precision - Nature is approximate.Comment: 38 page

Techniques - Ultrasound-guided percutaneous nephrolithotomy: How we do it.

Ultrasonography has emerged as an alternative to fluoroscopy for image-guided percutaneous nephrolithotomy (PCNL) in many countries. Compared to fluoroscopy-guided PCNL (F-PCNL), ultrasound-guided PCNL (US-PCNL) is easier to learn and reduces radiation exposure to patients and providers. Despite these advantages, uptake of ultrasound-guided PCNL (US-PCNL) in Canada has been almost nonexistent, largely because it is not incorporated into urologists' training. In this article, we seek to familiarize Canadian urologists with this approach by describing our step-by-step technique for US-PCNL. Additionally, we provide keys to successful implementation of this technique

Wider sampling reveals a non-sister relationship for geographically contiguous lineages of a marine mussel

The accuracy of phylogenetic inference can be significantly improved by the addition of more taxa and by increasing the spatial coverage of sampling. In previous studies, the brown mussel Perna perna showed a sister-lineage relationship between eastern and western individuals contiguously distributed along the South African coastline. We used mitochondrial (COI) and nuclear (ITS) sequence data to further analyze phylogeographic patterns within P.perna. Significant expansion of the geographical coverage revealed an unexpected pattern. The western South African lineage shared the most recent common ancestor (MRCA) with specimens from Angola, Venezuela, and Namibia, whereas eastern South African specimens and Mozambique grouped together, indicating a non-sister relationship for the two South African lineages. Two plausible biogeographic scenarios to explain their origin were both supported by the hypotheses-testing analysis. One includes an Indo-Pacific origin for P.perna, dispersal into the Mediterranean and Atlantic through the Tethys seaway, followed by recent secondary contact after southward expansion of the western and eastern South African lineages. The other scenario (Out of South Africa) suggests an ancient vicariant divergence of the two lineages followed by their northward expansion. Nevertheless, the Out of South Africa hypothesis would require a more ancient divergence between the two lineages. Instead, our estimates indicated that they diverged very recently (310 kyr), providing a better support for an Indo-Pacific origin of the two South African lineages. The arrival of the MRCA of P.perna in Brazil was estimated at 10 [0-40] kyr. Thus, the hypothesis of a recent introduction in Brazil through hull fouling in wooden vessels involved in the transatlantic itineraries of the slave trade did not receive strong support, but given the range for this estimate, it could not be discarded. Wider geographic sampling of marine organisms shows that lineages with contiguous distributions need not share a common ancestry.Portuguese National Science Foundation (FCT) [EXPL/BIA-BIC/1471/2012]; South Africa Research Chairs Initiative (SARChI) of the Department of Science and Technologyinfo:eu-repo/semantics/publishedVersio

Synthetic glycans control gut microbiome structure and mitigate colitis in mice

Relative abundances of bacterial species in the gut microbiome have been linked to many diseases. Species of gut bacteria are ecologically differentiated by their abilities to metabolize different glycans, making glycan delivery a powerful way to alter the microbiome to promote health. Here, we study the properties and therapeutic potential of chemically diverse synthetic glycans (SGs). Fermentation of SGs by gut microbiome cultures results in compound-specific shifts in taxonomic and metabolite profiles not observed with reference glycans, including prebiotics. Model enteric pathogens grow poorly on most SGs, potentially increasing their safety for at-risk populations. SGs increase survival, reduce weight loss, and improve clinical scores in mouse models of colitis. Synthetic glycans are thus a promising modality to improve health through selective changes to the gut microbiome

COAST (Cisplatin ototoxicity attenuated by aspirin trial): A phase II double-blind, randomised controlled trial to establish if aspirin reduces cisplatin induced hearing-loss

Background: Cisplatin is one of the most ototoxic chemotherapy drugs, resulting in a permanent and irreversible hearing loss in up to 50% of patients. Cisplatin and gentamicin are thought to damage hearing through a common mechanism, involving reactive oxygen species in the inner ear. Aspirin has been shown to minimise gentamicin-induced ototoxicity. We, therefore, tested the hypothesis that aspirin could also reduce ototoxicity from cisplatin-based chemotherapy. Methods: A total of 94 patients receiving cisplatin-based chemotherapy for multiple cancer types were recruited into a phase II, double-blind, placebo-controlled trial and randomised in a ratio of 1:1 to receive aspirin 975 mg tid and omeprazole 20 mg od, or matched placebos from the day before, to 2 days after, their cisplatin dose(s), for each treatment cycle. Patients underwent pure tone audiometry before and at 7 and 90 days after their final cisplatin dose. The primary end-point was combined hearing loss (cHL), the summed hearing loss at 6 kHz and 8 kHz, in both ears. Results: Although aspirin was well tolerated, it did not protect hearing in patients receiving cisplatin (p-value = 0.233, 20% one-sided level of significance). In the aspirin arm, patients demonstrated mean cHL of 49 dB (standard deviation [SD] 61.41) following cisplatin compared with placebo patients who demonstrated mean cHL of 36 dB (SD 50.85). Women had greater average hearing loss than men, and patients treated for head and neck malignancy experienced the greatest cHL. Conclusions: Aspirin did not protect from cisplatin-related ototoxicity. Cisplatin and gentamicin may therefore have distinct ototoxic mechanisms, or cisplatin-induced ototoxicity may be refractory to the aspirin regimen used here