bluuebunny/crossref_metadata_2025_split huggingface dataset:
The molecular structure of primary cilia revealed by cryo-electron tomography
Authors: Kiesel Petra , Viar Gonzalo Alvarez , Tsoy Nikolai , Maraspini Riccardo , Honigmann Alf , Pigino Gaia 
Published: March 2020

AbstractPrimary cilia are microtubule-based organelles involved in key signaling and sensing processes in eukaryotic cells. Unlike motile cilia, which have been thoroughly studied, the structure and the composition of primary cilia remain largely unexplored despite their fundamental role in development and homeostasis. They have for long been falsely regarded as simplified versions of motile cilia because they lack distinctive elements such as dynein arms, radial spokes, and central pair complex. However, revealing the detailed molecular composition and 3D structure of primary cilia is necessary in order to understand the mechanisms that govern their functions. Such structural investigations are so far being precluded by the challenging preparation of primary cilia for cryo-electron microscopy. Here, we developed an enabling method for investigating the structure of primary cilia at molecular resolution by cryo-electron tomography. We show that the well-known “9+0” arrangement of microtubule doublets is present only at the base of the primary cilium. A few microns away from the base the ciliary architecture changes into an unstructured bundle of EB1-decorated microtubule singlets and some actin filaments. Our results suggest the existence of a previously unobserved crosstalk between actin filaments and microtubules in the primary cilium. Our work provides unprecedented insights into the molecular structure of primary cilia and a general framework for uncovering their molecular composition and function in health and disease. This opens up new possibilities to study aspects of this important organelle that have so far been out of reach.
Mechanosensation Mediates Long-Range Spatial Decision-Making in an Aneural Organism
Authors: Murugan Nirosha J. , Kaltman Daniel H. , Jin Hong , Chien Melanie , Flores Ramses M. , Nguyen Cuong Q. , Tuzoff Dmitry , Minabutdinov Alexey , Kane Anna , Novak Richard , Ingber Donald E. , Levin Michael 
Published: March 2020

AbstractThe unicellular protistPhysarum polycephalumis an important emerging model for understanding how aneural organisms process information toward adaptive behavior. Here, we reveal thatPhysarumcan use mechanosensation to reliably make decisions about distant objects its environment, preferentially growing in the direction of heavier, substrate-deforming but chemically-inert masses. This long-range mass-sensing is abolished by gentle rhythmic mechanical disruption, changing substrate stiffness, or addition of a mechanosensitive transient receptor potential channel inhibitor. Computational modeling revealed thatPhysarummay perform this calculation by sensing the fraction of its growth perimeter that is distorted above a threshold strain – a fundamentally novel method of mechanosensation. Together, these data identify a surprising behavioral preference relying on biomechanical features and not nutritional content, and characterize a new example of an aneural organism that exploits physics to make decisions about growth and form.HighlightsThe aneural Physarum makes behavioral decisions by control of its morphologyIt has a preference for larger masses, which it can detect at long rangeThis effect is mediated by mechanosensing, not requiring chemical attractantsMachine learning reveals that it surveys environment and makes decision in < 4 hoursA biophysical model reveals how its pulsations enable long-distance mapping of environmental features
Gobies (Perciformes: Gobiidae) in Bolinao, northwestern Philippines
Authors: Stiefel Klaus M. , Manogan Dana P. , Cabaitan Patrick C. 
Published: March 2020

AbstractWe conducted a visual and photographic survey of the gobiidae in the Bolinao area of the Philipines, located on the western tip of the Lingayen gulf, on the west coast of Luzon island. We identified a total of 40 species, of which 18 are shrimp-associated. One species found (Myersina lachneri) constitutes a range expansion into the Philippines. This number of species is in the expected range compared to other studies of marine goby faunae in the coral triangle, despite the significant anthropogenic pressures onto the marine ecosystem in the surveyed area.
ZmCLA4 regulates leaf angle through multiple plant hormone-mediated signal pathways in maize
Authors: Dou Dandan , Han Shengbo , Ku Lixia , Liu Huafeng , Su Huihui , Ren Zhenzhen , Zhang Dongling , Zeng Haixia , Dong Yahui , Liu Zhixie , Zhu Fangfang , Zhao Qiannan , Xie Jiarong , Liu Yajing , Cheng Haiyang , Chen Yanhui 
Published: March 2020

AbstractLeaf angle in cereals is an important agronomic trait contributing to plant architecture and grain yield by determining the plant compactness. Although ZmCLA4 was identified to shape plant architecture by affecting leaf angle, the detailed regulatory mechanism of ZmCLA4 in maize remains unclear. ZmCLA4 was identified as a transcriptional repressor using the Gal4-LexA/UAS system and transactivation analysis in yeast. The DNA affinity purification (DAP)-seq assay showed that ZmCLA4 not only acts as a repressor containing the EAR motif (CACCGGAC), but was also found to have two new motifs, CCGARGS and CDTCNTC. On analyzing the ZmCLA4-bound targeted genes, we found that ZmCLA4, as a cross node of multiple plant hormone-mediated pathways, directly bound to ARF22 and IAA26 to regulate auxin transport and mediated brassinosteroid signaling by directly binding to BZR3 and 14-3-3. ZmCLA4 bound two WRKY genes involved with abscisic acid, two genes (CYP75B1, CYP93D1) involved with jasmonic acid, B3 involved in the response to ethylene, and thereby negatively regulated leaf angle formation. We built a new regulatory network for theZmCLA4gene controlling leaf angle in maize, which contributed to the understanding of ZmCLA4’s regulatory mechanism and will improve grain yields by facilitating optimization of plant architecture.
Association between social factors and gastrointestinal parasite product excretion in a group of non-cooperatively breeding carrion crows
Authors: Wascher Claudia A.F. 
Published: March 2020

AbstractThe social environment strongly affects the physiological stress response in group living animals, which in turn can affect the immune system and increase susceptibility to parasites. Here, I investigate relationships between social behavior and gastrointestinal parasite product excretion in the carrion crow (Corvus corone). Individuals from a population of non-cooperatively breeding carrion crows excreted less samples containing coccidian oocysts when kept in larger groups (8 or 9 individuals) compared to those individuals kept in smaller groups (2 or 3 individuals). Lower-ranking individuals excreted more samples containing parasite oocysts compared to higher-ranking individuals. The strength of affiliative relationships and number of related individuals in the group did not relate to the proportion of droppings containing coccidian oocysts. The present results confirm an association between social environment and parasite excretion patterns in carrion crows, but the patterns described in the present study differ from previously published data derived from a group of cooperatively breeding crows. This illustrates that differences between the social systems of carrion crows might result in different associations between the social environment and parasite product excretion patterns.Significance statementOne major cost of group living is an increase in susceptibility to parasites, however not all group living animals are affected by this in the same way. A better understanding how social behavior is associated with parasite burden can help to better understand evolution of group living. This study attempts to investigate associations between dominance rank, affiliative relationships as well as groups size and gastrointestinal parasite product excretion in a group of captive carrion crows. Lower-ranking individuals excreted more samples containing parasite oocysts compared to higher-ranking individuals, confirming an association between social relationships within the groups (for example dominance rank) and parasite excretion patterns.
Network resilience modelling: a New Zealand forestry supply chain case
Authors: Childerhouse Paul , Al Aqqad Mohammed , Zhou Quan , Bezuidenhout Carel 
Published: March 2020

PurposeThe objective of this research is to model supply chain network resilience for low frequency high impact disruptions. The outputs are aimed at providing policy and practitioner guidance on ways to enhance supply chain resilience.Design/methodology/approachThe research models the resilience of New Zealand's log export logistical network. A two-tier approach is developed; linear programming is used to model the aggregate-level resilience of the nation's ports, then discrete event simulation is used to evaluate operational constraints and validate the capacity of operational flows from forests to ports.FindingsThe synthesis of linear programming and discrete event simulation provide a holistic approach to evaluate supply chain resilience and enhance operational efficiency. Strategically increasing redundancy can be complimented with operational flexibility to enhance network resilience in the long term.Research limitations/implicationsThe two-tier modelling approach has only been applied to New Zealand's log export supply chains, so further applications are needed to insure reliability. The requirement for large quantities of empirical data relating to operational flows limited the simulation component to a single regionPractical implicationsNew Zealand's log export supply chain has low resilience; in most cases the closure of a port significantly constrains export capacity. Strategic selection of location and transportation mode by foresters and log exporters can significantly enhance the resilience of their supply chains.Originality/valueThe use of a two-tiered analytical approach enhances validity as each level's limitations and assumptions are addressed when combined with one another. Prior predominantly theoretical research in the field is validated by the empirical investigation of supply chain resilience.
Proposing a model of manager's strategic intelligence, organization development, and entrepreneurial behavior in organizations
Authors: Ahmadi Masoud , Baei Fahimeh , Hosseini-Amiri Seyyed-Mahmoud , Moarefi Alireza , Suifan Taghrid S. , Sweis Rateb 
Published: March 2020

PurposeThe main purpose of this article is to examine the relationship among the manager's Strategic Intelligence (SI) with Organization Development (OD), and Entrepreneurial Behaviour (EB) in governmental agencies in underdeveloped countries.Design/methodology/approachTo fulfill the purpose of this study, 274 staff were selected from a population of 480 based on stratified sampling. Descriptive and inferential statistics (including the measurement methods, KMO, Bartlett, Durbin–Watson, and path analysis tests) were performed by using SPSS22 software and Lisrel 8.5.FindingsBased on the results of the analysis, there is a positive significant relationship between the manager's SI and organizational development. Moreover, there is a positive significant relationship between the manager's SI and entrepreneurial behavior. However, examining the moderator variables including demographic characteristics revealed that the demographic characteristics have no effect on the manager's SI–OD relationship and manager's SI–EB relationship. Only gender influences the manager's SI–EB relationship.Practical implicationsThis research proposes a model of the relevant internal variables that have a positive effect on the organization's development and growth. The model is intended to help organizations gain competitive advantage and opportunity by improving the internal factors (managers' SI and entrepreneurial behavior of managers and staff) for the development and survival.Originality/valueThis study proposed a model of manager's SU, OD and Entrepreneurial Behavior in organizations based on data collected from underdeveloped countries. Also, the result of this study could be used by startup and entrepreneurial companies around the world.
The geographic mosaic in parallel: Matching patterns of newt tetrodotoxin levels and snake resistance in multiple predator–prey pairs
Authors: Reimche Jessica S. , Brodie Edmund D. , Stokes Amber N. , Ely Erica J. , Moniz Haley A. , Thill Vicki L. , Hallas Joshua M. , Pfrender Michael E. , Brodie Edmund D. , Feldman Chris R. 
Published: March 2020

Abstract

The Geographic Mosaic Theory of Coevolution predicts that coevolutionary arms races will vary over time and space because of the diverse ecological settings and population histories of interacting species across the landscape. Thus, understanding coevolution may require investigating broad sets of populations sampled across the range of the interaction. In addition, comparing coevolutionary dynamics between similar systems may reveal the importance of specific factors that structure coevolution.

Here, we examine geographic patterns of prey traits and predator traits in the relatively unstudied interaction between the Sierra garter snake (Thamnophis couchii) and sympatric prey, the rough‐skinned newt (Taricha granulosa), Sierra newt (Ta. sierrae) and California newt (Ta. torosa). This system parallels, in space and phenotypes, a classic example of coevolution between predatory common garter snakes (Th. sirtalis) and their toxic newt prey exhibiting hotspots of newt tetrodotoxin (TTX) levels and matching snake TTX resistance.

We quantified prey and predator traits from hundreds of individuals across their distributions, and functional trait matching at sympatric sites.

We show strong regional patterns of trait covariation across the shared ranges of Th. couchii and newt prey. Traits differ significantly among localities, with lower newt TTX levels and snake TTX resistance at the northern latitudes, and higher TTX levels and snake resistance at southern latitudes. Newts and snakes in northern populations show the highest degree of functional trait matching despite possessing the least extreme traits. Conversely, newts and snakes in southern populations show the greatest mismatch despite possessing exaggerated traits, with some snakes so resistant to TTX they would be unaffected by any sympatric newt. Nevertheless, individual variation was substantial, and appears to offer the opportunity for continued reciprocal selection in most populations.

Overall, the three species of newts appear to be engaged in a TTX‐mediated arms race with Th. couchii. These patterns are congruent with those seen between newts and Th. sirtalis, including the same latitudinal gradient in trait covariation, and the potential ‘escape’ from the arms race by snake predators. Such concordance in broad scale patterns across two distinct systems suggests common phenomena might structure geographic mosaics in similar ways.
Evidence for seasonal cycles in deep‐sea fish abundances: A great migration in the deep SE Atlantic?
Authors: Milligan Rosanna J. , Scott E. Marian , Jones Daniel O. B. , Bett Brian J. , Jamieson Alan J. , O’Brien Robert , Pereira Costa Sofia , Rowe Gilbert T. , Ruhl Henry A. , Smith Ken L. , de Susanne Philippe , Vardaro Michael F. , Bailey David M. 
Published: March 2020

Abstract

Animal migrations are of global ecological significance, providing mechanisms for the transport of nutrients and energy between distant locations. In much of the deep sea (>200 m water depth), the export of nutrients from the surface ocean provides a crucial but seasonally variable energy source to seafloor ecosystems. Seasonal faunal migrations have been hypothesized to occur on the deep seafloor as a result, but have not been documented.

Here, we analyse a 7.5‐year record of photographic data from the Deep‐ocean Environmental Long‐term Observatory Systems seafloor observatories to determine whether there was evidence of seasonal (intra‐annual) migratory behaviours in a deep‐sea fish assemblage on the West African margin and, if so, identify potential cues for the behaviour.

Our findings demonstrate a correlation between intra‐annual changes in demersal fish abundance at 1,400 m depth and satellite‐derived estimates of primary production off the coast of Angola. Highest fish abundances were observed in late November with a smaller peak in June, occurring approximately 4 months after corresponding peaks in primary production.

Observed changes in fish abundance occurred too rapidly to be explained by recruitment or mortality, and must therefore have a behavioural driver. Given the recurrent patterns observed, and the established importance of bottom‐up trophic structuring in deep‐sea ecosystems, we hypothesize that a large fraction of the fish assemblage may conduct seasonal migrations in this region, and propose seasonal variability in surface ocean primary production as a plausible cause. Such trophic control could lead to changes in the abundance of fishes across the seafloor by affecting secondary production of prey species and/or carrion availability for example.

In summary, we present the first evidence for seasonally recurring patterns in deep‐sea demersal fish abundances over a 7‐year period, and demonstrate a previously unobserved level of dynamism in the deep sea, potentially mirroring the great migrations so well characterized in terrestrial systems.
Species‐level drivers of mammalian ectoparasite faunas
Authors: Dáttilo Wesley , Barrozo‐Chávez Nathalia , Lira‐Noriega Andrés , Guevara Roger , Villalobos Fabricio , Santiago‐Alarcon Diego , Neves Frederico Siqueira , Izzo Thiago , Ribeiro Sérvio Pontes 
Published: March 2020

Abstract

Traditionally, most studies have described the organization of host–parasite interaction networks by considering only few host groups at limited geographical extents. However, host–parasite relationships are merged within different taxonomic groups and factors shaping these interactions likely differ between host and parasite groups, making group‐level differences important to better understand the ecological and evolutionary dynamics of these interactive communities.

Here we used a dataset of 629 ectoparasite species and 251 species of terrestrial mammals, comprising 10 orders distributed across the Nearctic and Neotropical regions of Mexico to assess the species‐level drivers of mammalian ectoparasite faunas. Specifically, we evaluated whether body weight, geographical range size and within‐range mammal species richness (i.e. diversity field) predict mammal ectoparasite species richness (i.e. degree centrality) and their closeness centrality within the mammal–ectoparasite network. In addition, we also tested if the observed patterns differ among mammal orders and if taxonomic closely related host mammals could more likely share the same set of ectoparasites.

We found that ectoparasite species richness of small mammals (mainly rodents) with large proportional range sizes was high compared to large‐bodied mammals, whereas the diversity field of mammals had no predictive value (except for bats). We also observed that taxonomic proximity was a main determinant of the probability to share ectoparasite species. Specifically, the probability to share ectoparasites in congeneric species reached up to 90% and decreased exponentially as the taxonomic distance increased.

Further, we also detected that some ectoparasites are generalists and capable to infect mammalian species across different orders and that rodents have a remarkable role in the network structure, being closely connected to many other taxa.

Hence, because many rodent species have synanthropic habits they could act as undesired reservoirs of disease agents for humans and urban animals. Considering the reported worldwide phenomenon of the proliferation of rodents accompanying the demographic decrease or even local extinction of large‐bodied mammal species, these organisms may already be an increasing health threat in many regions of the world.
Immunological outcomes in infants with ROP after dexamethasone and aminophylline
Authors: Balashova Larisa , Bykovskaya Svetlana , Korobova Ludmila , Kuznetsova Yulia , Kantardgy Elena , Mukhin Vladimir , Popov Andrey 
Published: March 2020

AbstractThis research aims to improve anaesthesia services given to preterm infants by the use of dexamethasone and aminophylline administrated under sevoflurane, and to analyze its effect on the cell‐mediated immunity (CD4+CD25+Foxp3+(T‐reg) and CD4+CD25highFoxp3+CD127low). We have examined 74 premature babies with retinopathy of prematurity (ROP) at the 3–5 stages during the 25–32 week gestation period (1–6 months after birth). Both immunomodulators had no significant effect on clinical parameters after one dose (P > .05). Aminophylline (2.4% solution, 0.1 mL/kg or 0.132 mL per infant on average) and dexamethasone (0.4% solution, 0.1 mg/kg or 0.132 mL per infant on average) were intravenously injected 15 minutes before the end of the surgery. Required anaesthesia depth was maintained with inhalation anaesthetic (1.5–2.0 IAC), and the minimum fresh gas flow was not less than 2 L. Blood samples were taken from the vein (anaesthesia induction stage) into the tubes containing EDTA (the anticoagulant), stored at 20–25°C, and then, processed and stained within 24 hours after sampling. Both immunomodulators had no significant effect on clinical parameters after one dose (P > .05). Short‐term shift in regulatory T‐cell level affected by dexamethasone has a negative effect combined with further withdrawal effect that this hormonal drug has. Aminophylline has such clinical effects as improving pulmonary ventilation, decrease in apnoea frequency, and improving blood gas indices. Aminophylline has less expressed but more prolonged positive effect during the day when used for several days. It may lead to a persistent positive effect with progressive treatment outcomes.
Modeling the buffer capacity of ingredients in salad dressing products
Authors: Longtin Madyson , Price Robert E. , Mishra Ritu , Breidt Fred 
Published: March 2020

AbstractThe pH of most acid food products depends on undefined and complex buffering of ingredients but is critically important for regulatory purposes and food safety. Our objective was to define the buffer capacity (BC) of ingredients in salad dressing products. Ingredients of salad dressings were titrated individually and in combination using concentrations typical of dressing products. Titration curves from pH 2 to 12 were generated with sodium hydroxide and hydrochloric acid, which were then used to generate BC curves. A matrix of concentration and pK values for a series of monoprotic buffers approximated the pH of each ingredient. Some buffer series required anion or cation corrections for accurate pH prediction, possibly due to the presence of salts of acid or bases. Most buffers had BC values less than 10‐fold the BC of acetic acid (0.25 β) typically in dressing formulations and had little influence on the final product pH of the dressings tested. Unexpectedly, we found that sugars in dressing formulations, including sucrose or corn syrup, exhibited buffering at pH values greater than 11 (0.035 β and 0.059 β, respectively), which was likely due to weakly acidic hydroxyl groups on the sugar molecules. However, the concentration and pK for buffers above pH 11 or below pH 2 were difficult to quantify due to the BC of water. The BC data may help to quantify the effects of salad dressing ingredients on the final product pH and benefit regulatory agencies and manufacturers in assessing product pH and safety.Practical ApplicationBuffer capacity data for salad dressing ingredients may help determine the influence ingredient addition will have on the final pH of a salad dressing product. The addition of low acid ingredients with little or no buffering may not significantly alter pH. The modeling method may be useful for regulatory purposes to estimate the effects of low acid ingredients on pH changes for food safety and may also be useful for product development of acid and acidified foods.