The evolving role of preprints in the dissemination of COVID-19 research and their impact on the science communication landscape

The world continues to face a life-threatening viral pandemic. The virus underlying the Coronavirus Disease 2019 (COVID-19), Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has caused over 98 million confirmed cases and 2.2 million deaths since January 2020. Although the most recent respiratory viral pandemic swept the globe only a decade ago, the way science operates and responds to current events has experienced a cultural shift in the interim. The scientific community has responded rapidly to the COVID-19 pandemic, releasing over 125,000 COVID-19–related scientific articles within 10 months of the first confirmed case, of which more than 30,000 were hosted by preprint servers. We focused our analysis on bioRxiv and medRxiv, 2 growing preprint servers for biomedical research, investigating the attributes of COVID-19 preprints, their access and usage rates, as well as characteristics of their propagation on online platforms. Our data provide evidence for increased scientific and public engagement with preprints related to COVID-19 (COVID-19 preprints are accessed more, cited more, and shared more on various online platforms than non-COVID-19 preprints), as well as changes in the use of preprints by journalists and policymakers. We also find evidence for changes in preprinting and publishing behaviour: COVID-19 preprints are shorter and reviewed faster. Our results highlight the unprecedented role of preprints and preprint servers in the dissemination of COVID-19 science and the impact of the pandemic on the scientific communication landscape.

An analysis of bioRxiv and medRxiv during the first 10 months of the COVID-19 pandemic reveals that the pandemic has resulted in a cultural shift in the use of preprints for disseminating pandemic-related science.     

The lens eyes of the box jellyfish <Emphasis Type="Italic">Tripedalia cystophora</Emphasis> and <Emphasis Type="Italic">Chiropsalmus sp.</Emphasis> are slow and color-blind

Box jellyfish, or cubomedusae, possess an impressive total of 24 eyes of four morphologically different types. Compared to other cnidarians they also have an elaborate behavioral repertoire, which for a large part seems to be visually guided. Two of the four types of cubomedusean eyes, called the upper and the lower lens eye, are camera type eyes with spherical fish-like lenses. Here we explore the electroretinograms of the lens eyes of the Caribbean species, Tripedalia cystophora, and the Australian species, Chiropsalmus sp. using suction electrodes. We show that the photoreceptors of the lens eyes of both species have dynamic ranges of about 3 log units and slow responses. The spectral sensitivity curves for all eyes peak in the blue-green region, but the lower lens eye of T. cystophora has a small additional peak in the near UV range. All spectral sensitivity curves agree well with the theoretical absorbance curve of a single opsin, strongly suggesting color-blind vision in box jellyfish with a single receptor type. A single opsin is supported by selective adaptation experiments.     

Early effects of tobacco smoke exposure on vascular dynamics in the microcirculation.

The purpose of these studies is to examine the early effects of chronic tobacco smoke exposure on vascular dynamics in the mesenteric microcirculation. Female rats were exposed daily to tobacco smoke from five reference cigarettes for a period of 2 mo. At the end of this period the smoke-treated rats had gained 12 g less than sham-treated controls, and arterial blood pressure in the smoke-treated animals was slightly less than pressure in the sham-treated animals. These are characteristic effects of tobacco smoke exposure on rats. Following the treatment period, red blood cell (RBC) velocity in single mesenteric capillaries and microvascular pressures in arterioles and venules were measured in accordance to established methods. There was no significant difference in pressure distribution on the arterial side of the mesenteric vascular network, but pressure in the venules of the smoke-treated animals was significantly higher than that of the sham-treated group. In association with the higher venular pressure in the smoke-treated animals, capillary RBC velocity (an index of capillary flow) was significantly lower. The reduction in velocity was in proportion to the decrease in pressure drop (arteriole-venule) across the capillary network.     

Post-translational control of the long and winding road to cholesterol

The synthesis of cholesterol requires more than 20 enzymes, many of which are intricately regulated. Post-translational control of these enzymes provides a rapid means for modifying flux through the pathway. So far, several enzymes have been shown to be rapidly degraded through the ubiquitin–proteasome pathway in response to cholesterol and other sterol intermediates. Additionally, several enzymes have their activity altered through phosphorylation mechanisms. Most work has focused on the two rate-limiting enzymes: 3-hydroxy-3-methylglutaryl CoA reductase and squalene monooxygenase. Here, we review current literature in the area to define some common themes in the regulation of the entire cholesterol synthesis pathway. We highlight the rich variety of inputs controlling each enzyme, discuss the interplay that exists between regulatory mechanisms, and summarize findings that reveal an intricately coordinated network of regulation along the cholesterol synthesis pathway. We provide a roadmap for future research into the post-translational control of cholesterol synthesis, and no doubt the road ahead will reveal further twists and turns for this fascinating pathway crucial for human health and disease.     

Shoot Na+ Exclusion and Increased Salinity Tolerance Engineered by Cell Type–Specific Alteration of Na+ Transport in Arabidopsis

Soil salinity affects large areas of cultivated land, causing significant reductions in crop yield globally. The Na⁺ toxicity of many crop plants is correlated with overaccumulation of Na⁺ in the shoot. We have previously suggested that the engineering of Na⁺ exclusion from the shoot could be achieved through an alteration of plasma membrane Na⁺ transport processes in the root, if these alterations were cell type specific. Here, it is shown that expression of the Na⁺ transporter HKT1;1 in the mature root stele of Arabidopsis thaliana decreases Na⁺ accumulation in the shoot by 37 to 64%. The expression of HKT1;1 specifically in the mature root stele is achieved using an enhancer trap expression system for specific and strong overexpression. The effect in the shoot is caused by the increased influx, mediated by HKT1;1, of Na⁺ into stelar root cells, which is demonstrated in planta and leads to a reduction of root-to-shoot transfer of Na⁺. Plants with reduced shoot Na⁺ also have increased salinity tolerance. By contrast, plants constitutively expressing HKT1;1 driven by the cauliflower mosaic virus 35S promoter accumulated high shoot Na⁺ and grew poorly. Our results demonstrate that the modification of a specific Na⁺ transport process in specific cell types can reduce shoot Na⁺ accumulation, an important component of salinity tolerance of many higher plants.     

Demonstration of neurosecretory substance in previously scanned specimens: adaptation of the Gomori aldehyde-fuchsin method for correlative SEM/TEM/LM histochemistry.

The Gomori aldehyde-fuchsin (AF) method for selective staining of neurosecretory substance (NSS) has been adapted to tissue previously prepared for both scanning and transmission electron microscopy (SEM/TEM). The procedure results in precise correlation of light microscopic (LM) histochemistry with SEM/TEM of the same tissue.     

Effects of obtaining a blood culture on subsequent management of young febrile children without an evident focus of infection.

To assess the effects of obtaining a blood culture on the subsequent diagnostic and therapeutic management of young febrile children without an evident focus of bacterial infection, we carried out a randomized controlled clinical trial of this procedure in 146 children 3 to 24 months of age who presented to our emergency department with an unexplained temperature of 39.0 degrees C or higher. Random assignment to either have (67 children) or not have (79) a blood sample taken for culture resulted in groups equivalent in age, sex, weight, socioeconomic status, temperature at enrolment and laboratory test results. No differences were detected in the rates of subsequent hospital admission, outpatient visits, determination of complete blood count or other blood tests, urinalysis or urine culture, chest or other roentgenography, or administration of antibiotics or other medications. Knowledge of the absence of such differences should be helpful in evaluating the relative benefits and costs of blood culture for young febrile children.     

Increase in liver acid lipase of thyroidectomized rats by thyroid hormones and its inhibition by actinomycin D

Acid lipase activity in the livers of thyroidectomized rats is increased by administration of L-thyroxine. The response is dose-dependent and can be demonstrated within 12 h after treatment. L-Triiodothyronine also evokes a rapid increase in acid lipase activity, and this increase can be inhibited by co-administration of actinomycin D.     

Biology of Oxyeleotris heterodon and its major prey,Ophieleotris aporos,two floodplain sleepers (Pisces: Eleotrididae) of the Sepik River fishery,northern Papua New Guinea

Synopsis Oxyeleotris heterodon attains 483 mm standard length (1.83 kg) and Ophieleotris aporos 245 mm (0.171 kg). Both species feature significantly in the local fishery in lowlands. Ophieleotris aporos is approximately one hundred times more abundant than Ox. heterodon in catches and landings which were influenced by river flood conditions in both species. Oxyeleotris heterodon is predominantly piscivorous but also eats Macrobrachium spp. prawns; fish prey consumed are almost exclusively Op. aporos. Ophieleotris aporos is omnivorous and feeds mainly on aquatic insects. Condition, fat deposition, feeding and reproduction in Op. aporos were related to the flood cycle with increases in the flood season; in Ox. heterodon variations in these factors related more to the availability of Op. aporos, seasonal changes being less marked. Ophieleotris aporos matures at a small size, has large gonads, small eggs and is highly fecund; Ox. heterodon exhibited opposite trends in these life-history characteristics by comparison. Reproductive styles adopted by the two species are interpreted in relation to the different predation pressures they experience. Oxyeleotris heterodon may not be adapted to high adult mortality and the fisheries implications of this are discussed.