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Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments, such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, and generally lacked quantitative measurements. Here, we report the development, implementation, and initial results of a multilingual, international questionnaire to assess self-reported quantity and quality of perception in 3 distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, and 8 others, aged 19-79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste, and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change ±100) revealed a mean reduction of smell (-79.7 ± 28.7, mean ± standard deviation), taste (-69.0 ± 32.6), and chemesthetic (-37.3 ± 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell but also affects taste and chemesthesis. The multimodal impact of COVID-19 and the lack of perceived nasal obstruction suggest that severe acute respiratory syndrome coronavirus strain 2 (SARS-CoV-2) infection may disrupt sensory-neural mechanisms.

Harmful algal blooms (HAB) are natural environmental occurrences that can disrupt ecosystem function that supports fisheries and aquaculture, as well as rendering harvested seafood, especially shellfish, unsafe for consumption by humans or wildlife species. Many dinoflagellates that cause HAB have a life cycle with a sexually produced resting stage called the resting cyst. The resting cyst enables the species to persist in an area where conditions for growth vary seasonally. These species often are found as vegetative stages only during a short period of the year. Most of the time is spent dormant or quiescent as thick-walled resting cysts with very low metabolic activity. By summarizing findings from an iterative series of research projects investigating different parts of the sexual life cycle, a more complete picture of the role of the sexual stages emerges, illuminating the consequences of life cycle within the environmental context. Gametes, the sexual stages, are formed at the end of the growing season in response to environmental signals which remain largely unknown. Gametes have lower cell-specific density and different swimming behavior compared to vegetative cells. Specifically, vegetative cells perform daily vertical migrations; whereas, gametes accumulate in patterns influenced by lower cell-specific density, changed swimming behavior, and attraction to each other. The patterns and patches of accumulated gametes (sexually induced cells) aggregate into larger and larger patterns. Together with large-scale hydrographic water movements, such as upwelling, water stratification, and fronts, cells originating from a low vegetative cell density background distribution assemble and become concentrated within a constricted space, thus forming a dense "bloom." This process is distinctly different from the paradigm of blooms resulting from simple, vegetative cell divisions. Undisturbed blooms of cyst-producing dinoflagellate gametes end with gamete fusion into diploid zygotes that transform into resting cysts. The resting cysts sink according to shape and cell-specific density into the silt fraction of the sediment. Cyst preservation depends upon the oxygenation level of the sediment and the presence of fauna. Hypoxic/anoxic conditions lower cyst mortality from benthic grazers. The reestablishment of motile, vegetative cells occurs under seasonally favorable conditions, and successful population growth depends upon environmental conditions, such as weather and nutrient availability. Factors that increase HAB risks of resting cyst-producing dinoflagellates are eutrophication leading to high cell numbers and high cyst preservation in hypoxic benthic zones. Hydrographic factors causing increased cell accumulation also are important, and intensified water stratification can amplify encystment success. These insights underscore mechanisms by which climate change is affecting HAB ecology and subsequent effects upon marine and coastal fisheries and aquaculture. [ABSTRACT FROM AUTHOR]

This article describes how data are used to analyze the pattern of ionization energies of the lanthanide elements. Different observed pathways of ionization between different ground states are discussed, and the effects of pairing, exchange, and orbital interactions on ionization energies of the lanthanides are evaluated. When all the above effects are taken into account, the pattern of ionization energies of the lanthanide elements is similar to that of the main group elements and increases across the period from left to right. (Contains 2 notes, 3 tables, and 8 figures.)

This quantitative dinoflagellate cyst study reveals an enormous difference in survival rates in oxygenated versus anoxic sediments. Replicate samples of concentrated natural dinoflagellate cysts with the same initial species composition (1.4 × 104 resting cysts·cm−3 sediment, 61% filled with live-appearing contents) were placed in bags of 20 µm plankton screen. Replicate bags containing 10.0 cm−3 concentrated cyst samples were placed on the seafloor in different environments in Long Island Sound, USA (anoxic and oxygenated), as well as refrigerated in test tubes in the laboratory. Three sets of 15 bags were placed in each environment. Once every year for four consecutive years, three bags were recovered from each set, and the contents were analyzed by cyst counting and germination experiments. An enormous difference in preservation potential between samples in oxygenated versus anoxic environments was revealed. The number of dinoflagellate cysts decreased abruptly within the first year in the oxygen-rich environment; living cysts became very rare (only 5% remained) and also empty walls of cysts disappeared (20% of total cysts remained). In anoxic sediment samples, living cysts also decreased significantly with time, but less quickly. After 1 year, 35% of the living cysts in the anoxic environment and 70% of the living cysts refrigerated in test tubes remained intact. After 4 years, 21% of the cysts with contents in the anoxic environment remained, and 31% in test tubes. The empty cyst walls remained intact for a longer time under anoxic conditions, especially of species known to fossilize well. Germination experiments showed that cysts with live-appearing contents were likely alive, because species with identifiable live-appearing cysts were also identified as vegetative cells in corresponding slurry cultures. The cyst assemblage was dominated by Protoperidinaceae, Dipolopsalidaceae, and Gonyaulacaceae. Of special interest is the ichthyotoxic Margalefodinium polykrikoides, the bloom-forming Peridinium quinquecorne, which has an undescribed resting cyst, and a previously undescribed Krypoperidinium species. The results show greater preservation of dinoflagellate cysts in "dead-zone sea bottoms" and may also provide an answer to the question of the absence of cyst beds in an area despite observed sedimentation of dense blooms. [ABSTRACT FROM AUTHOR]

Theories of perception have traditionally dismissed the sense of smell as a notoriously variable and highly subjective sense, mainly because it does not easily fit into accounts of perception based on visual experience. So far, philosophical questions about the objects of olfactory perception have started by considering the nature of olfactory experience. However, there is no philosophically neutral or agreed conception of olfactory experience: it all depends on what one thinks odors are. We examine the existing philosophical methodology for addressing our sense of smell: on the one hand appeals to phenomenology that focus on the experiential dimensions of odor perception and on the other approaches that look at odor sources and their material dimensions. We show that neither strategy provides enough information to account for the human sense of smell and argue that the inclusion of the missing dimension of biology, with its concern for the function (or functions) of olfaction, provides the means to develop a satisfactory and empirically informed philosophy of smell. [ABSTRACT FROM AUTHOR]

ABSTRACT Scrippsiella spp. resting cysts, unlike many other dinoflagellate cysts, possess an outer layer of calcite beneath which is a thin sporopollenin wall. This feature may affect cyst survival through [...]

ABSTRACT Large-scale, open, microalgal feed cultures for hatchery and nursery production of marine invertebrates inevitably becomes contaminated with various microbes that can affect productivity and usability of the harvested biomass. [...]

Olfactory dysfunction is amongst the many symptoms of Long COVID. Whilst most people that experience smell loss post COVID-19 recover their sense of smell and taste within a few weeks, about 10% of cases experience long-term problems, and their smell recovery journey often begins a few months later when everyday items start to smell distorted. This is known as parosmia. The aim of this study was to identify the key food triggers of parosmic distortions and investigate the relationship between distortion and disgust in order to establish the impact of parosmia on diet and quality of life. In this cross-sectional study (n = 727), respondents experiencing smell distortions completed a questionnaire covering aspects of smell loss, parosmia and the associated change in valence of everyday items. There was a significant correlation between strength and disgust (p < 0.0001), and when the selected items were reported as distorted, they were described as either unpleasant or gag-inducing 84% of the time. This change in valence associated with loss of expected pleasure and the presence of strange tastes and burning sensations must certainly lead to changes in eating behaviours and serious longer-term consequences for mental health and quality of life. [ABSTRACT FROM AUTHOR]

One previously unstudied aspect of differences between sexual and asexual life stages in large‐scale transport and accumulation is density (mass per unit volume) of cells in each life stage. The specific density was determined for Scrippsiella lachrymosa cells in medium with and without nitrogen (N) enrichment through density‐gradient centrifugation. Growth medium without N addition is often called "encystment medium" when used for the purpose of resting cyst formation in cyst‐forming dinoflagellates; mating gametes are usually seen after 2–3 days. Significant differences in specific density were found after 2 days in encystment medium simultaneously with the observation of typical gamete swimming behavior and mating. The specific density of cells in encystment medium was 1.06 g · cm−3; whereas, the specific density of cells in growth medium was 1.11 g · cm−3. Cells in encystment medium were found to have significantly increased lipid content, reduced chlorophyll content, and reduced internal complexity. The findings may explain differential transport of less dense and chemotactically aggregating gametes into surface blooms in contrast to denser vegetative cells that perform daily vertical migration and do not aggregate. Passive accumulation of non‐migrating gametes into layers in stagnant water also can be explained, as well as sinking of zygotes when the storage of highly dense starch increases. Resting cysts had a density of over 1.14 g · cm−3 and would sink to become part of the silt fraction of the sediment. We suggest that differences in behavior and buoyancy between sexual and asexual life stages cause differences in cell accumulation, and therefore large‐scale, environmental transport could be directly dependent upon life‐cycle transitions. [ABSTRACT FROM AUTHOR]

A museum or gallery is usually thought of as a space containing objects arranged in a chosen way. Understanding the multisensory factors that modulate an audience's experiences of artworks in their settings offers museum curators and architects opportunities to enhance visitors' sensory engagement with their collections. Barry C Smith, Director of the Institute of Philosophy, Centre for the Study of the Senses, School of Advanced Study, University of London, considers a number of ways this can happen. [ABSTRACT FROM AUTHOR]

The ionization energies of atoms and atomic ions in the s,p,d,and f blocks of the periodic table are reviewed. The irregular behavior of the first and second ionization energies across the transition metal and rare earth periods is explained in terms of electronic configurations of atoms and ions.

The growth of continuously generated, large-scale datasets, and new analytics to handle them, has created expectations, in some quarters, that new insights can be generated that will help us address the biggest challenges that face us as a species and therefore can shape future societal outcomes. It is hoped that these new technologies will lead not just to new discoveries but also to new questions and thinking that will deliver significant scientific advances. Perhaps there will be some genuine scientific advances but since many of the challenges that face us reside in the human world and depend upon how humans behave, we need to turn to the humanities and the social sciences as well as the natural sciences and look at the role Big Data could play there in adding to, or shaping, our future. And here, what concerns us is not just the assumptions guiding the new analytic techniques for data mining, data merging, linking and analysis, born out of smarter AI algorithms, it is a more fundamental issue about the constraints and limitations of the kind of data inputs and outputs being appealed to in Big Data systems and whether they are well served to provide an understanding of the human world. [ABSTRACT FROM AUTHOR]

Background: Although most Scotch whisky is blended from different casks, a firm distinction exists in the minds of consumers and in the marketing of Scotch between single malts and blended whiskies. Consumers are offered cultural, geographical and production reasons to treat Scotch whiskies as falling into the categories of blends and single malts. There are differences in the composition, method of distillation and origin of the two kinds of bottled spirits. But does this category distinction correspond to a perceptual difference detectable by whisky drinkers? Do experts and novices show differences in their perceptual sensitivities to the distinction between blends and single malts? To test the sensory basis of this distinction, we conducted a series of blind tasting experiments in three countries with different levels of familiarity with the blends versus single malts distinction (the UK, the USA and France). In each country, expert and novice participants had to perform a free sorting task on nine whiskies (four blends, four single malts, one single grain, plus one repeat) first by olfaction, then by tasting. Results: Overall, no reliable perceptual distinction was revealed in the tasting condition between blends and single malts by experts or novices when asked to group whiskies according to their similarities and differences. There was nonetheless a clear effect of expertise, with experts showing a more reliable classification of the repeat sample. French experts came closest to a making a distinction between blends and single malts in the olfactory condition, which might be explained by a lack of familiarity with blends. Interestingly, the similarity between the blends and some of their ingredient single malts explained more of participants' groupings than the dichotomy between blends and single malts. Conclusions: The firmly established making and marketing distinction between blends and single malts corresponds to no broad perceptually salient difference for whisky tasters, whether experts or novices. The present study indicates that successfully blended whiskies have their own distinctive and recognizable profiles, taking their place in a common similarity space, with groupings that can reflect their component parts. [ABSTRACT FROM AUTHOR]

Various life cycle stages of cyst-producing dinoflagellates often appear differently colored under the microscope; gametes appear paler while zygotes are darker in comparison to vegetative cells. To compare physiological and photochemical competency, the pigment composition of discrete life cycle stages was determined for the common resting cyst-producing dinoflagellate Scrippsiella lachrymosa. Vegetative cells had the highest cellular pigment content (25.2 ± 0.5 pg · cell−1), whereas gamete pigment content was 22% lower. The pigment content of zygotes was 82% lower than vegetative cells, even though they appeared darker under the microscope. Zygotes of S. lachrymosa contained significantly higher cellular concentrations of β-carotene (0.65 ± 0.15 pg · cell−1) than all other life stages. Photoprotective pigments and the de-epoxidation ratio of xanthophylls-cycle pigments in S. lachrymosa were significantly elevated in zygotes and cysts compared to other stages. This suggests a role for accessory pigments in combating intracellular oxidative stress during sexual reproduction or encystment. Resting cysts contained some pigments even though chloroplasts were not visible, suggesting that the brightly colored accumulation body contained photosynthetic pigments. The differences in pigmentation between life stages have implications for interpretation of pigment data from field samples when sampled during dinoflagellate blooms. [ABSTRACT FROM AUTHOR]

Two mesocosm experiments were conducted to study the interaction of a commercial oyster-nursery system with the surrounding embayment, specifically, nutrient and plankton dynamics. The nursery was stocked with 80-200 L of oysters, sized 3-5 mm. Ambient water and the water passed through the oyster nursery were incubated in mesocosms, and nutrients and plankton were monitored over the course of 27-h incubations. The first experiment conducted in July 2009 captured a phytoplankton community dominated by Peridinium quinquecorne, a rare dinoflagellate not previously reported in the northeastern USA. Dissolved nitrogen compounds in all mesocosms were depleted within the first 6 h. The second experiment was conducted in September 2009, when a more typical and diverse phytoplankton community was present. Unlike the first experiment, Nitrate plus nitrite in the mesocosms was not depleted. Both experiments indicated little difference between the water passed through the oyster nursery and the ambient water in terms of subsequent nutrient and plankton dynamics, indicating little 'legacy effect' of the oyster nursery upon nutrients and plankton in this embayment. This conclusion was reached under the specific operating conditions typical for this nursery system, as chosen by the commercial partner in the study; changes in oyster stocking or flow rate are likely to change the results. [ABSTRACT FROM AUTHOR]

This paper briefly describes the many different sets of ionic and covalent radii available. A simple model of ionic and covalent bonding is proposed and an equation to calculate internuclear distances of covalent, ionic and metallic lattices is described. Derivation of covalent radii and the use of a proposed model of metallic structure and bonding to derive ionic radii are discussed. A brief summary of the development of the simple equation for calculating internuclear distances of ionic compounds is provided. Values of internuclear distances calculated from the derived radii are compared to observed values and give good agreement, showing strong evidence that ionic and covalent radii are not additive and electronegativity influences bonding and internuclear distances. Ionic radii derived from the proposed model are applied to calculate lattice energies which agree well with literature values/values calculated by the Born Haber cycle. Work functions of transition metals are shown to be simple inverse functions of the derived radii. Internuclear distances of inter-metallic compounds are calculated and compared with observed values to show good agreement. This work shows that the proposed model of metallic structure complements the band theory and expressions introduced in this work can be used to predict ionic and covalent bond lengths (in different environments) that have not yet been determined as well as being a method for resolving bond type. [ABSTRACT FROM AUTHOR]

The article discusses the role of metacognition to the individual. The author talks about the ide of psychologist Joelle Proust about the role of metacognition in constituting oneself as a person. Also tackled is the recommendation of Proust about the understanding of the notion, metacognition is an indispensible part of the toolkit for the human mind.

This paper discusses in detail the calculation of internuclear distances of heteronuclear single bond covalent molecules in the gaseous state. It reviews briefly the effect of electronegativity in covalent bond length. A set of single bond covalent radii and electronegativity values are proposed. Covalent bond lengths calculated by an adapted form of a simple expression (which calculated internuclear separation of different Group 1 and Group 2 crystalline salts to a remarkable degree of accuracy) show very good agreement with observed values. A small number of bond lengths with double bonds as well as bond lengths in the crystalline state are calculated using the same expression and when compared with observed values also give good agreement. This work shows that covalent radii are not additive and that radii in the crystalline state are different from those in the gaseous state. The results also show that electronegativity is a major influence on covalent bond lengths and the set of electronegativity scale and covalent radii proposed in this work can be used to calculate covalent bond lengths in different environments that have not yet been experimentally measured. [ABSTRACT FROM AUTHOR]

Is relativism about truth ever a coherent doctrine? Some people have argued that an answer to this question depends on whether there can be cases of genuine disagreement where those who disagree hold conflicting beliefs towards the same proposition and yet are each entitled to say that what they believe is true. These have been called cases of faultless disagreement and are often explored by considering the case of disagreements about taste. However, this is not the right way to formulate the relativist's doctrine, and the discussions of taste are often based on a faulty view about the nature of taste and about the workings of predicates of taste. I examine the taste case in more detail and consider the prospects for a genuine form of truth relativism. [ABSTRACT FROM AUTHOR]

Is relativism about truth ever a coherent doctrine? Some people have argued that an answer to this question depends on whether there can be cases of genuine disagreement where those who disagree hold conflicting beliefs towards the same proposition and yet are each entitled to say that what they believe is true. These have been called cases of faultless disagreement and are often explored by considering the case of disagreements about taste. However, this is not the right way to formulate the relativist's doctrine, and the discussions of taste are often based on a faulty view about the nature of taste and about the workings of predicates of taste. I examine the taste case in more detail and consider the prospects for a genuine form of truth relativism. [ABSTRACT FROM AUTHOR]

ABSTRACT: Differences of evaluative judgments are often assumed to be a reason to prefer pluralism, relativism or subjectivism to objectivism, and this preference is even more pronounced in the case of judgements of taste. A comparison between perceptual and moral disagreements, however, enables us to understand that differences in judgments may be due to a difference in access to the situation or object, and not necessarily to a difference in value. The feeling of irresolvable differences that sometimes arises in situations of evaluation, may not hold in the absence of objective values and / or common values, but be due to a difficulty or inability to capture the perspective, or circumstances of assessment wherein the other agents are placed. [ABSTRACT FROM PUBLISHER]

The relationship among pricing, revenue management (RM) controls and capacity directly impacts the profitability potential of an airline's schedule. Too much capacity in a market leads to wide open RM controls with deeply discounted prices to stimulate demand to fill the available seats at unprofitable yields. On the other hand, a schedule that does not supply enough capacity can lead to higher prices and stringent controls that invite competition. Understanding the relationship between the scheduled capacity, pricing structure and RM controls gives an airline the opportunity to better align scheduled capacity, adjust pricing structures and manage the seat inventory to maximize profitability. This article provides a practical approach to understanding the impact of scheduled capacity and pricing structures on overall network revenue. A macro-level metric known as the ‘price balance statistic’ is described for evaluating the quality of a given pricing strategy and guiding a search algorithm to identify an optimal alignment between pricing structure, scheduled capacity and RM controls using marginal revenue principles. [ABSTRACT FROM AUTHOR]

Online travel retailing is an e-commerce success story. Different retail models exist to sell travel products over the web. These models include online travel agencies, supplier websites, distressed inventory websites, reverse auction web sites, shopping bots, search engines, and portals. Online travel agencies, such as Expedia and Travelocity, are the most mature business accounting for more than half of online leisure travel sales. Online travel agencies acquire inventory from multiple airlines, hotels, car rental companies, cruise lines, and event organisers. They merchandise this inventory as standalone as well as packaged categories to online shoppers who benefit from a wide variety of products across multiple suppliers. In this paper, a decision support framework for an online travel agency is discussed. The framework includes disaggregate demand estimation, pricing and product display, marketing, revenue planning, and deal evaluation. The underlying Operations Research models is discussed along with challenges associated with data collection and implementation. The authors discuss the impact of online travel retailing on supplier yield management systems. Decision support models discussed are also applicable to online travel retailers other than online travel agencies. The decision support framework should serve as an exposition to the Operations Research opportunities in the emerging field of online travel retailing.Journal of Revenue and Pricing Management (2006) 5, 72–80. doi:10.1057/palgrave.rpm.5160012 [ABSTRACT FROM AUTHOR]