bluuebunny/crossref_metadata_2025 huggingface dataset:
The promise of immunotherapy in genitourinary malignancies
Authors: Zhang Tian , Armstrong Andrew J , George Daniel J , Huang Jiaoti
Published: December 2018

A broad understanding of the tumor immune landscape has led to a revolution of immune checkpoint inhibitors in the treatment of multiple cancer types. In genitourinary malignancies, immune checkpoint inhibitors have improved outcomes for patients with metastatic renal cell carcinoma and metastatic urothelial carcinoma; however, these treatments have not yet proven broadly beneficial for patients with metastatic prostate cancer. Numerous prospective trials are ongoing to further improve outcomes with immunotherapy combinations and for biomarker development to predict benefit from immune checkpoint inhibition. This perspective article highlights our current immunotherapy approaches in each of the genitourinary malignancies and the ongoing clinical trials that may inform our future treatments in renal, urothelial, and prostate cancers.
RADIATION DOSES TO ANAESTHETISTS DURING PROSTATIC ARTERY EMBOLIZATION INTERVENTIONAL PROCEDURES
Authors: Garzón W J , Khoury H J
Published: December 2018

The objective of this study was to assess the radiation doses received by anaesthetists from prostatic artery embolization (PAE) procedures. Ten PAE procedures conducted in a reference hospital in the city of Recife, Brazil were investigated. Occupational dosimetry was performed using thermoluminescent dosemeters which were located next to the eyes, close to the thyroid (over the shielding), on the thorax (under the apron), on the wrist and on the feet of the physician’s body. The results showed that the anaesthetist’s feet received the highest doses followed by the eyes and the hands. In some complex PAE procedures the doses received by anaesthetists on the lens of the eyes and the effective dose were higher than those received by the main operator due to the anaesthetist’s close position to the patient’s table and the use of oblique projections. The personal dose equivalent Hp(3) per procedure for the anaesthetist’s right eyebrow ranged from 20.2 μSv to 568.3 μSv. This result shows that anaesthetists assisting PAE procedures can exceeds the annual eye lens dose limit of 20 mSv recommended by the ICRP with only one procedure per week if radiation protection measures are not implemented during procedures.
The cultural foundations of economic categories: finance and class in the marginalist revolution
Authors: Kaldor Yair
Published: December 2018

Economic categories are part of the everyday concepts people use to apprehend social reality. While scholars recognize their importance for social and economic processes, it is not clear how these categories develop when reality itself changes. I address this issue with a framework that incorporates a cultural emphasis on meaning-making with a macro-structural analysis of the conditions in which they take place. I apply this framework to the marginalist revolution of the late 19th century, which marks the birth of neoclassical economics and focus on the new understanding of ‘value’ that emerged during this period. I trace it to the rise of finance and the problem of price fluctuations, and show how its class standpoint helps explain the different outcomes of the marginalist revolution in England, Austria and France. The analysis provides insights into the power of economic ideas and the cultural dimension of structural changes.
Effects of extended-release eprinomectin on productivity measures in cow–calf systems and subsequent feedlot performance and carcass characteristics of calves
Authors: Andresen Claire E , Loy Dan D , Brick Troy A , Schulz Lee L , Gunn Patrick J
Published: December 2018

The objective of this study was to estimate the impact of a single injection of extended-release eprinomectin on economically relevant production variables in beef cows and calves as well as subsequent feedlot health, performance, and carcass traits of calves compared with a traditional, short duration anthelmintic. Animals from 13 cooperator herds across seven states were stratified within herd and assigned to one of two treatments; injectable doramectin (DOR; Dectomax; n = 828) or injectable eprinomection (EPR; Longrange; n = 832). Fecal samples were randomly collected from a subset of cows at both treatment and the end of grazing to evaluate fecal egg count (FEC). Continuous and categorical data were analyzed using the MIXED and GLIMMIX procedures of SAS, respectively. Cow treatment body weight (BW) and final BW were not different (P ≥ 0.40) between treatments. There were no differences (P ≥ 0.12) between treatments in cow ADG, change in BW, or body condition scores during the grazing season. While FEC at treatment did not differ (P = 0.18), cows treated with EPR had lower final FEC at the end of the grazing season (P = 0.02) and a greater reduction of FEC over the grazing season (P = 0.01). Calf treatment BW, weaning BW, and ADG did not differ between treatments (P ≥ 0.34). Incidence of pinkeye tended to be less (P = 0.06) for cows treated with EPR but was not different for calves (P = 0.43). Conception to AI, overall pregnancy rates, and calving interval were not different between treatments (P ≥ 0.45). A subset of calves from each herd was sent to Tri-County Steer Carcass Futurity (TCSCF) feedlot for the finishing phase. Calf BW did not differ at initiation of feeding (P = 0.20). While EPR calves tended to be heavier at reimplantation (P = 0.07), final BW and overall ADG were not different between treatments (P ≥ 0.13). Health records indicated lower morbidity for EPR calves (P = 0.05). Carcass performance including HCW, dressing percent, backfat, KPH, REA, YG, were not different between treatment groups (P ≥ 0.12). However, EPR calves had a greater marbling score, greater average quality grade (P < 0.01), and higher proportion of calves that graded average choice or greater (P = 0.03). Results of this study indicate no difference in cow or preweaning calf performance, however, carcass quality in the feedlot phase was improved. Thus, economic analysis indicates opportunities for return on investment if animals treated with EPR have improved health status and/or carcass quality during the feeding phase.
The impact of farrowing room noise on sows’ reactivity to piglets
Authors: Chapel Nichole M , Radcliffe J Scott , Stewart Kara R , Lucas Jeffrey R , Lay Donald C
Published: December 2018

Despite much interest in sow welfare, the impact of the acoustic environment on sow reactivity to her piglets is rarely considered. The objective of this study was to understand the impact of noise produced by mechanical ventilation and other sows on a sow’s reactivity to her piglets. Sows were farrowed in one of three environments: 1) with eight other sows exposed to constant fan noise (GROUP-FAN; n = 10), 2) alone with fan noise present (ISO-FAN; n = 10), and 3) alone without fans running (ISO-QUIET; n = 10). Sows were subjected for 5 min to a piglet removal event (REMOVAL) by an unknown handler twice, at 24 and 48 h postfarrowing. During a REMOVAL, sows were observed via video recording for changes in posture, eating and drinking behavior, and head orientation. Audio was recorded to quantify vocalizations by the sow. Once piglets were returned, sows underwent further behavior observations for 10 min (RETURN), resulting in approximately 15 min of total video observation. Sows were classified as young (second and third parity) and old (fifth parity and older). The YOUNG sows tended to be more Alert (looking toward the handler or their piglets) during REMOVE than OLD sows (P = 0.07; 2.01 and 1.33, respectively). The ISO-FAN sows vocalized the loudest during REMOVAL (P < 0.001) with ISO-QUIET sows performing the quietest vocalizations (GROUP-FAN: 72.22 ± 1.06 dB; ISO-FAN: 73.61 ± 1.07 dB; ISO-QUIET: 67.41 ± 0.99 dB). During RETURN, YOUNG sows spent more time sitting than OLD sows (P < 0.01; 7.48 ± 1.6% and 0.91 ± 1.8%, respectively). The ISO-QUIET sows tended to have more posture changes during the RETURN with ISO-FAN having the least changes (P = 0.06; GROUP-FAN: 1.23 ± 0.4; ISO-FAN: 0.44 ± 0.3; ISO-QUIET: 1.61 ± 0.4). Finally, sows decreased the amount of time Alert in the second RETURN (P = 0.03; first: 3.9 ± 0.6%; second: 2.5 ± 0.6%). Overall, sows acclimated to the removal and return events with decreased vocalizations and decreased Alert behaviors in the second REMOVAL and RETURN. Additionally, YOUNG sows performed more active behaviors than OLD sows, indicating that sows may become less interested in or cannot hear their piglets as they age. Finally, there is some indication that ventilation presence has an effect on sow–piglet communication with ISO-FAN sows having the loudest vocalizations when compared with sows without ventilation noise, indicating that ventilation noise may be a possible competitor with a sow’s ability to communicate with her piglets.
Methylene Blue Administration During and After Life-Threatening Intoxication by Hydrogen Sulfide: Efficacy Studies in Adult Sheep and Mechanisms of Action
Authors: Haouzi Philippe , Tubbs Nicole , Cheung Joseph , Judenherc-Haouzi Annick
Published: December 2018

Exposure to toxic levels of hydrogen sulfide (H2S) produces an acute cardiac depression that can be rapidly fatal. We sought to characterize the time course of the cardiac effects produced by the toxicity of H2S in sheep, a human sized mammal, and to describe the in vivo and in vitro antidotal properties of methylene blue (MB), which has shown efficacy in sulfide intoxicated rats. Infusing NaHS (720 mg) in anesthetized adult sheep produced a rapid dilation of the left ventricular with a decrease in contractility, which was lethal within about 10 min by pulseless electrical activity. MB (7 mg/kg), administered during sulfide exposure, maintained cardiac contractility and allowed all of the treated animals to recover. At a dose of 350 mg NaHS, we were able to produce an intoxication, which led to a persistent decrease in ventricular function for at least 1 h in nontreated animals. Administration of MB, 3 or 30 min after the end of exposure, whereas all free H2S had already vanished, restored cardiac contractility and the pyruvate/lactate (P/L) ratio. We found that MB exerts its antidotal effects through at least 4 different mechanisms: (1) a direct oxidation of free sulfide; (2) an increase in the pool of “trapped” H2S in red cells; (3) a restoration of the mitochondrial substrate-level phosphorylation; and (4) a rescue of the mitochondrial electron chain. In conclusion, H2S intoxication produces acute and long persisting alteration in cardiac function in large mammals even after all free H2S has vanished. MB exerts its antidotal effects against life-threatening sulfide intoxication via multifarious properties, some of them unrelated to any direct interaction with free H2S.
A Response to Gupta et al. (2019) Regarding the MoT3 Wheat Blast Diagnostic Assay
Authors: Yasuhara-Bell Jarred , Pieck Michael L. , Ruck Amy , Farman Mark L. , Peterson Gary L. , Stack James P. , Valent Barbara , Pedley Kerry F.
Published: December 2018

This is a response to a recent Letter to the Editor of Phytopathology, in which Gupta et al. (2019) caution against the indiscriminate use of the MoT3 diagnostic assay that distinguishes isolates of Magnaporthe oryzae in the Triticum lineage from those that do not cause aggressive wheat blast. We confirm that the assay does reliably distinguish between wheat and rice isolates from Bangladesh and worldwide, as described in the original paper by Pieck et al. (2017) . We have been unable to reproduce the equally intense amplification of WB12 and WB12-like sequences reported in Figure 1 of the Letter. Other data presented by Gupta et al. (2019) support the specificity of the MoT3 assay. Therefore, cautions beyond those always associated with accurate reproduction of diagnostic assays are unwarranted.
Rehabilitation treatment of spastic cerebral palsy with radial extracorporeal shock wave therapy and rehabilitation therapy
Authors: Lin Yongjie , Wang Guowei , Wang Bingchen
Published: December 2018

This aims to investigate the effect of combined use of radial extracorporeal shock wave therapy (rESWT) and conventional rehabilitation therapy on postoperative rehabilitation of children with spastic cerebral palsy.

Children with spastic cerebral palsy 6 weeks after multistage surgery were randomly divided into treatment group (received rESWT and conventional rehabilitation therapy) and control group (received conventional rehabilitation only). Before treatment, 2 weeks and 1 month after treatment, the Gross Motor Function Measure (GMFM), modified Ashworth Scale (MAS) of the hamstrings and triceps, plantar area and plantar pressure were examined for efficacy assessment.

A total of 82 children with spastic cerebral palsy were recruited, including 43 children in treatment group and 39 children in control group. There was no significant difference in the age, MAS score, and GMFM score between the 2 groups before treatment. There were statistically significant differences between the 2 groups at 2 weeks and 4 weeks after treatment, including the MAS score, GMFM score, plantar area and plantar pressure (P < .05). Within groups, there were also significant differences at different times (P < .05).

The rESWT combined with rehabilitation can quickly and effectively relieve paralysis of lower extremities, reduce the tension of hamstrings and calf muscles, relieve muscle spasm, and rapidly improve limb function in children with spastic cerebral palsy.
Symmetry breaking and inter-clonal behavioural variability in a slime mould
Authors: Vogel David , Dussutour Audrey , Deneubourg Jean-Louis
Published: December 2018

Cells are dynamic systems capable of switching from isotropic growth to polarized growth even in the absence of any pre-existing external asymmetry. Here, we study this process of symmetry breaking in the acellular slime mouldPhysarum polycephalum. In these experiments, slime moulds could grow on two identical opposed sources of calcium. We highlighted a positive correlation between growth dynamic, level of symmetry breaking and calcium concentration. We identified three populations of slime moulds within our clonal lineage with similar symmetry breaking behaviours but different motility characteristics. These behavioural differences between slime moulds emerged in the absence of any environmental differences. Such behavioural plasticity could generate cellular diversity, which can be critical for survival.
Continuous and discrete quantity discrimination in tortoises
Authors: Gazzola Andrea , Vallortigara Giorgio , Pellitteri-Rosa Daniele
Published: December 2018

The ability to estimate quantity, which is crucially important in several aspects of animal behaviour (e.g. foraging), has been extensively investigated in most taxa, with the exception of reptiles. The few studies available, in lizards, report lack of spontaneous discrimination of quantity, which may suggest that reptiles could represent an exception in numerical abilities among vertebrates. We investigated the spontaneous ability of Hermann's tortoises (Testudo hermanni) to select the larger quantity of food items. Tortoises were able to choose the larger food item when exposed to two options differing in size, but equal in numerousness (0.25, 0.50, 0.67 and 0.75 ratio) and when presented with two groups differing in numerousness, but equal in size (1 versus 4, 2 versus 4, 2 versus 3 and 3 versus 4 items). The tortoises succeeded in both size and numerousness discrimination, and their performance appeared to depend on the ratio of items to be discriminated (thus following Weber's Law). These findings in chelonians provide evidence of an ancient system for the extrapolation of numerical magnitudes from given sets of elements, shared among vertebrates.
Whole angiospermsWolffia columbianadisperse by gut passage through wildfowl in South America
Authors: Silva G. G. , Green A. J. , Weber V. , Hoffmann P. , Lovas-Kiss Á. , Stenert C. , Maltchik L.
Published: December 2018

For the first time to our knowledge, we demonstrate that whole angiosperm individuals can survive gut passage through birds, and that this occurs in the field. Floating plants of the genusWolffiaare the smallest of all flowering plants. Fresh droppings of white-faced whistling duckDendrocygna viduata(n= 49) and coscoroba swanCoscoroba coscoroba(n= 22) were collected from Brazilian wetlands. IntactWolffia columbianawere recovered from 16% ofD. viduataand 32% ofCoscorobasamples (total = 164 plantlets). The viability of plants was tested, and asexual reproduction was confirmed.Wolffia columbianais an expanding alien in Europe. Avian endozoochory of asexual angiosperm propagules may be an important, overlooked dispersal means for aquatic plants, and may contribute to the invasive character of alien species.
Female assortative mate choice functionally validates synthesized male odours of evolving stickleback river–lake ecotypes
Authors: Gahr Christoph L. , Boehm Thomas , Milinski Manfred
Published: December 2018

During mate choice decisions, females of many vertebrates use male olfactory cues to achieve immunogenetic optimality of their offspring. Three-spined sticklebacks (Gasterosteus aculeatus) populating habitats that differ in their parasite communities evolve locally adapted combinations of genetic variants encoded at the major histocompatibility complex (MHC). Such adaptation confers optimal resistance to the local parasite fauna. Immunogenetic signatures co-evolved with local parasites favour population-specific assortative mate choice behaviour. Previous studies have shown that female sticklebacks evaluate male MHC-associated olfactory cues during the process of mate choice, but how habitat-specific information is exchanged between males and females has remained elusive. Here, we directly demonstrate the molecular nature of the olfactory cue providing habitat-specific information. Under controlled laboratory conditions, females that are ready to mate prefer mixtures of synthetic MHC peptide ligands mimicking the optimal allele number of their original population. These results imply that female sticklebacks can determine the number of MHC alleles of their prospective mates, compare it to their own immunogenetic status, and, if optimal with respect to the immunogenetic complementarity, accept the male as mate. Our results suggest a potentially common mechanism of ecological speciation in vertebrates that is based on the olfactory assessment of habitat-specific immunogenetic diversity.
Automated sequence-level analysis of kinetics and thermodynamics for domain-level DNA strand-displacement systems
Authors: Berleant Joseph , Berlind Christopher , Badelt Stefan , Dannenberg Frits , Schaeffer Joseph , Winfree Erik
Published: December 2018

As an engineering material, DNA is well suited for the construction of biochemical circuits and systems, because it is simple enough that its interactions can be rationally designed using Watson–Crick base pairing rules, yet the design space is remarkably rich. When designing DNA systems, this simplicity permits using functional sections of each strand, called domains, without considering particular nucleotide sequences. However, the actual sequences used may have interactions not predicted at the domain-level abstraction, and new rigorous analysis techniques are needed to determine the extent to which the chosen sequences conform to the system’s domain-level description. We have developed a computational method for verifying sequence-level systems by identifying discrepancies between the domain-level and sequence-level behaviour. This method takes a DNA system, as specified using the domain-level tool Peppercorn, and analyses data from the stochastic sequence-level simulator Multistrand and sequence-level thermodynamic analysis tool NUPACK to estimate important aspects of the system, such as reaction rate constants and secondary structure formation. These techniques, implemented as the Python package KinDA, will allow researchers to predict the kinetic and thermodynamic behaviour of domain-level systems after sequence assignment, as well as to detect violations of the intended behaviour.
The role of turbulent hydrodynamics and surface morphology on heat and mass transfer in corals
Authors: Stocking Jonathan B. , Laforsch Christian , Sigl Robert , Reidenbach Matthew A.
Published: December 2018

Corals require efficient heat and mass transfer with the overlying water column to support key biological processes, such as nutrient uptake and mitigation of thermal stress. Transfer rates are primarily determined by flow conditions, coral morphology and the physics of the resulting fluid–structure interaction, yet the relationship among these parameters is poorly understood especially for wave-dominated coral habitats. To investigate the interactive effects of these factors on fluxes of heat and mass, we measure hydrodynamic characteristics
in situ
over three distinct surface morphologies of massive stony corals in a Panamanian reef. Additionally, we implement a numerical model of flow and thermal transport for both current and wave conditions past a natural coral surface, as well as past three simplified coral morphologies with varying ratios of surface roughness spacing-to-height. We find oscillatory flow enhances rates of heat and mass transfer by 1.2–2.0× compared with unidirectional flow. Additionally, increases in Reynolds number and in surface roughness ratio produce up to a 3.3× and a 2.0× enhancement, respectively. However, as waves begin to dominate the flow regime relative to unidirectional currents, the underlying physical mechanisms mediating transfer rates shift from predominantly turbulence-driven to greater control by inertial accelerations, resulting in larger heat and mass transfer for small surface roughness ratios. We show that for rough corals in wave-dominated flows, novel trade-off dynamics for heat and mass transfer exist between broadly spaced roughness that enhances turbulence production versus narrowly spaced roughness that produces greater surface area. These findings have important implications for differential survivorship during heat-induced coral bleaching, particularly as thermal stress events become increasingly common with global climate change.
Optimization of topological complexity for one-dimensional arterial blood flow models
Authors: Fossan Fredrik E. , Mariscal-Harana Jorge , Alastruey Jordi , Hellevik Leif R.
Published: December 2018

As computational models of the cardiovascular system are applied in modern personalized medicine, maximizing certainty of model input becomes crucial. A model with a high number of arterial segments results in a more realistic description of the system, but also requires a high number of parameters with associated uncertainties. In this paper, we present a method to optimize/reduce the number of arterial segments included in one-dimensional blood flow models, while preserving key features of flow and pressure waveforms. We quantify the preservation of key flow features for the optimal network with respect to the baseline networks (a 96-artery and a patient-specific coronary network) by various metrics and quantities like average relative error, pulse pressure and augmentation pressure. Furthermore, various physiological and pathological states are considered. For the aortic root and larger systemic artery pressure waveforms a network with minimal description of lower and upper limb arteries and no cerebral arteries, sufficiently captures important features such as pressure augmentation and pulse pressure. Discrepancies in carotid and middle cerebral artery flow waveforms that are introduced by describing the arterial system in a minimalistic manner are small compared with errors related to uncertainties in blood flow measurements obtained by ultrasound.
Reusable building blocks in biological systems
Authors: Mireles Victor , Conrad Tim O. F.
Published: December 2018

One of the most widely recognized features of biological systems is their modularity. The modules that constitute biological systems are said to be
redeployed and combined
across several conditions, thus acting as building blocks. In this work, we analyse to what extent are these building blocks reusable as compared with those found in randomized versions of a system. We develop a notion of decompositions of systems into phenotypic building blocks, which allows them to overlap while maximizing the number of times a building block is reused across several conditions. Different biological systems present building blocks whose reusability ranges from single use (e.g. condition specific) to constitutive, although their average reusability is not always higher than random equivalents of the system. These decompositions reveal a distinct distribution of building block sizes in real biological systems. This distribution stems, in part, from the peculiar usage pattern of the elements of biological systems, and constitutes a new angle to study the evolution of modularity.
Particle-based computational modelling of arterial disease
Authors: Ahmadzadeh H. , Rausch M. K. , Humphrey J. D.
Published: December 2018

Accumulated glycosaminoglycans (GAGs) can sequester water and induce swelling within the intra-lamellar spaces of the medial layer of an artery. It is increasingly believed that stress concentrations caused by focal swelling can trigger the damage and delamination that is often seen in thoracic aortic disease. Here, we present computational simulations using an extended smoothed particle hydrodynamics approach to examine potential roles of pooled GAGs in initiating and propagating intra-lamellar delaminations. Using baseline models of the murine descending thoracic aorta, we first calculate stress distributions in a healthy vessel. Next, we examine increases in mechanical stress in regions surrounding GAG pools. The simulations show that smooth muscle activation can partially protect the wall from swelling-associated damage, consistent with experimental observations, but the wall can yet delaminate particularly in cases of smooth muscle dysfunction or absence. Moreover, pools of GAGs located at different but nearby locations can extend and coalesce, thus propagating a delamination. These findings, combined with a sensitivity study on the input parameters of the model, suggest that localized swelling can alter aortic mechanics in ways that eventually can cause catastrophic damage within the wall. There is, therefore, an increased need to consider roles of GAGs in aortic pathology.
Thin-film models for an active gel
Authors: Kitavtsev G. , Münch A. , Wagner B.
Published: December 2018

In this study, we present a free-boundary problem for an active liquid crystal starting with the Beris–Edwards theory that uses a tensorial order parameter and includes active contributions to the stress tensor and then derive from it the Eriksen model for an active polar gel and scalar order parameter to analyse the rich defect structure observed in applications such as the adenosinetriphosphate-driven motion of a thin film of an actin filament network. The small aspect ratio of the film geometry allows for an asymptotic approximation of the free-boundary problem in the limit of weak elasticity of the network and strong active terms. The new thin-film model captures the defect dynamics in the bulk as well as wall defects and thus presents a significant extension of previous models based on the Leslie–Erickson–Parodi theory. As an example we derive the explicit solution for an active gel confined to a channel, which has discontinuous director profile leading to a bidirectional flow structure generated by the active terms.
Testing causal quantum theory
Authors: Kent Adrian
Published: December 2018

Causal quantum theory assumes that measurements or collapses are well-defined physical processes, localized in space–time, and never give perfectly reliable outcomes and that the outcome of one measurement only influences the outcomes of others within its future light cone. Although the theory has unusual properties, it is not immediately evident that it is inconsistent with experiment to date. I discuss its implications and experimental tests.
Empathy modulates the temporal structure of social attention
Authors: Hedger Nicholas , Haffey Anthony , McSorley Eugene , Chakrabarti Bhismadev
Published: December 2018

Individuals with low empathy often show reduced attention towards social stimuli. A limitation of this literature is the lack of empirical work that has explicitly characterized how this relationship manifests itself over time. We investigate this issue by analysing data from two large eye-tracking datasets (total
n
= 176). Via growth-curve analysis, we demonstrate that self-reported empathy (as measured by the empathy quotient—EQ) predicts the temporal evolution of gaze behaviour under conditions where social and non-social stimuli compete for attention. In both datasets, we found that EQ not only predicted a global increase in social attention, but predicted a different temporal profile of social attention. Specifically, we detected a reliable effect of empathy on gaze towards social images after prolonged viewing. An analysis of switch latencies revealed that low-EQ observers switched gaze away from an initially fixated social image more frequently and at earlier latencies than high-EQ observers. Our analyses demonstrate that modelling these temporal components of gaze signals may reveal useful behavioural phenotypes. The explanatory power of this approach may provide enhanced biomarkers for conditions marked by deficits in empathy-related processes.
Oxygen, temperature and the deep-marine stenothermal cradle of Ediacaran evolution
Authors: Boag Thomas H. , Stockey Richard G. , Elder Leanne E. , Hull Pincelli M. , Sperling Erik A.
Published: December 2018

Ediacaran fossils document the early evolution of complex megascopic life, contemporaneous with geochemical evidence for widespread marine anoxia. These data suggest early animals experienced frequent hypoxia. Research has thus focused on the concentration of molecular oxygen (O
2
) required by early animals, while also considering the impacts of climate. One model, the Cold Cradle hypothesis, proposed the Ediacaran biota originated in cold, shallow-water environments owing to increased O
2
solubility. First, we demonstrate using principles of gas exchange that temperature does have a critical role in governing the bioavailability of O
2
—but in cooler water the supply of O
2
is actually lower. Second, the fossil record suggests the Ediacara biota initially occur approximately 571 Ma in deep-water facies, before appearing in shelf environments approximately 555 Ma. We propose an ecophysiological underpinning for this pattern. By combining oceanographic data with new respirometry experiments we show that in the shallow mixed layer where seasonal temperatures fluctuate widely, thermal and partial pressure (
p
O
2
) effects are highly synergistic. The result is that temperature change away from species-specific optima impairs tolerance to low
p
O
2
. We hypothesize that deep and particularly stenothermal (narrow temperature range) environments in the Ediacaran ocean were a physiological refuge from the synergistic effects of temperature and low
p
O
2
.
Inter-stride variability triggers gait transitions in mammals and birds
Authors: Granatosky Michael C. , Bryce Caleb M. , Hanna Jandy , Fitzsimons Aidan , Laird Myra F. , Stilson Kelsey , Wall Christine E. , Ross Callum F.
Published: December 2018

Speed-related gait transitions occur in many animals, but it remains unclear what factors trigger gait changes. While the most widely accepted function of gait transitions is that they reduce locomotor costs, there is no obvious metabolic trigger signalling animals when to switch gaits. An alternative approach suggests that gait transitions serve to reduce locomotor instability. While there is evidence supporting this in humans, similar research has not been conducted in other species. This study explores energetics and stride variability during the walk–run transition in mammals and birds. Across nine species, energy savings do not predict the occurrence of a gait transition. Instead, our findings suggest that animals trigger gait transitions to maintain high locomotor rhythmicity and reduce unstable states. Metabolic efficiency is an important benefit of gait transitions, but the reduction in dynamic instability may be the proximate trigger determining when those transitions occur.
Ultra-high matrix mineralization of sperm whale auditory ossicles facilitates high sound pressure and high-frequency underwater hearing
Authors: Schmidt Felix N. , Delsmann Maximilian M. , Mletzko Kathrin , Yorgan Timur A. , Hahn Michael , Siebert Ursula , Busse Björn , Oheim Ralf , Amling Michael , Rolvien Tim
Published: December 2018

The auditory ossicles—malleus, incus and stapes—are the smallest bones in mammalian bodies and enable stable sound transmission to the inner ear. Sperm whales are one of the deepest diving aquatic mammals that produce and perceive sounds with extreme loudness greater than 180 dB and frequencies higher than 30 kHz. Therefore, it is of major interest to decipher the microstructural basis for these unparalleled hearing abilities. Using a suite of high-resolution imaging techniques, we reveal that auditory ossicles of sperm whales are highly functional, featuring an ultra-high matrix mineralization that is higher than their teeth. On a micro-morphological and cellular level, this was associated with osteonal structures and osteocyte lacunar occlusions through calcified nanospherites (i.e. micropetrosis), while the bones were characterized by a higher hardness compared to a vertebral bone of the same animals as well as to human auditory ossicles. We propose that the ultra-high mineralization facilitates the unique hearing ability of sperm whales. High matrix mineralization represents an evolutionary conserved or convergent adaptation to middle ear sound transmission.
Stress behaviour and physiology of developing Arctic barnacle goslings (
Branta leucopsis
) is affected by legacy trace contaminants
Authors: Scheiber Isabella B. R. , Weiß Brigitte M. , de Jong Margje E. , Braun Anna , van den Brink Nico W. , Loonen Maarten J. J. E. , Millesi Eva , Komdeur Jan
Published: December 2018

Natural populations are persistently exposed to environmental pollution, which may adversely impact animal physiology and behaviour and even compromise survival. Responding appropriately to any stressor ultimately might tip the scales for survival, as mistimed behaviour and inadequate physiological responses may be detrimental. Yet effects of legacy contamination on immediate physiological and behavioural stress coping abilities during acute stress are virtually unknown. Here, we assessed these effects in barnacle goslings (
Branta leucopsis
) at a historical coal mine site in the Arctic. For three weeks we led human-imprinted goslings, collected from nests in unpolluted areas, to feed in an abandoned coal mining area, where they were exposed to trace metals. As control we led their siblings to feed on clean grounds. After submitting both groups to three well-established stress tests (group isolation, individual isolation, on-back restraint), control goslings behaved calmer and excreted lower levels of corticosterone metabolites. Thus, legacy contamination may decisively change stress physiology and behaviour in long-lived vertebrates exposed at a young age.
High species richness and lineage diversity of reef corals in the mesophotic zone
Authors: Muir Paul R. , Wallace Carden C. , Pichon Michel , Bongaerts Pim
Published: December 2018

Coral reefs are increasingly threatened by thermal bleaching and tropical storm events associated with rising sea surface temperatures. Deeper habitats offer some protection from these impacts and may safeguard reef-coral biodiversity, but their faunas are largely undescribed for the Indo-Pacific. Here, we show high species richness of scleractinian corals in mesophotic habitats (30–125 m) for the northern Great Barrier Reef region that greatly exceeds previous records for mesophotic habitats globally. Overall, 45% of shallow-reef species (less than or equal to 30 m), 78% of genera, and all families extended below 30 m depth, with 13% of species, 41% of genera, and 78% of families extending below 45 m. Maximum depth of occurrence showed a weak relationship to phylogeny, but a strong correlation with maximum latitudinal extent. Species recorded in the mesophotic had a significantly greater than expected probability of also occurring in shaded microhabitats and at higher latitudes, consistent with light as a common limiting factor. The findings suggest an important role for deeper habitats, particularly depths 30–45 m, in preserving evolutionary lineages of Indo-Pacific corals. Deeper reef areas are clearly more diverse than previously acknowledged and therefore deserve full consideration in our efforts to protect the world's coral reef biodiversity.
Post-Cretaceous bursts of evolution along the benthic-pelagic axis in marine fishes
Authors: Ribeiro Emanuell , Davis Aaron M. , Rivero-Vega Rafael A. , Ortí Guillermo , Betancur-R Ricardo
Published: December 2018

Ecological opportunity arising in the aftermath of mass extinction events is thought to be a powerful driver of evolutionary radiations. Here, we assessed how the wake of the Cretaceous–Palaeogene (K-Pg) mass extinction shaped diversification dynamics in a clade of mostly marine fishes (Carangaria), which comprises a disparate array of benthic and pelagic dwellers including some of the most astonishing fish forms (e.g. flatfishes, billfishes, remoras, archerfishes). Analyses of lineage diversification show time-heterogeneous rates of lineage diversification in carangarians, with highest rates reached during the Palaeocene. Likewise, a remarkable proportion of Carangaria's morphological variation originated early in the history of the group and in tandem with a marked incidence of habitat shifts. Taken together, these results suggest that all major lineages and body plans in Carangaria originated in an early burst shortly after the K-Pg mass extinction, which ultimately allowed the occupation of newly released niches along the benthic-pelagic habitat axis.
Resource stoichiometry shapes community invasion resistance via productivity-mediated species identity effects
Authors: Yang Tianjie , Han Gang , Yang Qingjun , Friman Ville-Petri , Gu Shaohua , Wei Zhong , Kowalchuk George A. , Xu Yangchun , Shen Qirong , Jousset Alexandre
Published: December 2018

Diversity–invasion resistance relationships are often variable and sensitive to environmental conditions such as resource availability. Resource stoichiometry, the relative concentration of different elements in the environment, has been shown to have strong effects on the physiology and interactions between different species. Yet, its role for diversity–invasion resistance relationships is still poorly understood. Here, we explored how the ratio of nitrogen (N) and phosphorus affects the productivity and invasion resistance of constructed microbial communities by a plant pathogenic bacterium,
Ralstonia solanacearum
. We found that resource stoichiometry and species identity effects affected the invasion resistance of communities. Both high N concentration and resident community diversity constrained invasions, and two resident species, in particular, had strong negative effects on the relative density of the invader and the resident community productivity. While resource stoichiometry did not affect the mean productivity of the resident community, it favoured the growth of two species that strongly constrained invasions turning the slope of productivity–invasion resistance relationship more negative. Together our findings suggest that alterations in resource stoichiometry can change the community resistance to invasions by having disproportionate effects on species growth, potentially explaining changes in microbial community composition under eutrophication.
Macroecology of birds potentially susceptible to West Nile virus
Authors: Tolsá María J. , García-Peña Gabriel E. , Rico-Chávez Oscar , Roche Benjamin , Suzán Gerardo
Published: December 2018

Zoonotic diseases transmitted by wildlife affect biological conservation, public and animal health, and the economy. Current research efforts are aimed at finding wildlife pathogens at a given location. However, a meta-analytical approach may reveal emerging macroecological patterns in the host–pathogen relationship at different temporal and spatial scales. West Nile virus (WNV) is a pathogen with worldwide detrimental impacts on bird populations. To understand macroecological patterns driving WNV infection, we aimed to recognize unknown competent reservoirs using three disease metrics—serological prevalence (SP), molecular prevalence (MP) and mortality (M)—and test if these metrics are correlated with the evolutionary history, geographical origin of bird species, viral strain, time–space and methodology. We performed a quantitative review of field studies on birds sampled for WNV. We obtained 4945 observations of 949 species from 39 countries. Our analysis supported the idea that MP and M are good predictors of reservoir competence, and allowed us to identify potential competent reservoirs. Furthermore, results indicated that the variability of these metrics was attributable to phylogeny, time–space and sample size. A macroecological approach is needed to recognize susceptible species and competent reservoirs, and to identify other factors driving zoonotic diseases originating from wildlife.
Expansion in geographical and morphological space drives continued lineage diversification in a global passerine radiation
Authors: Kennedy Jonathan D. , Borregaard Michael K. , Marki Petter Z. , Machac Antonin , Fjeldså Jon , Rahbek Carsten
Published: December 2018

Why diversification rates vary so extensively across the tree of life remains an important yet unresolved issue in biology. Two prominent and potentially independent factors proposed to explain these trends reflect the capacity of lineages to expand into new areas of (i) geographical or (ii) ecological space. Here, we present the first global assessment of how diversification rates vary as a consequence of geographical and ecological expansion, studying these trends among 15 speciose passerine families (together approximately 750 species) using phylogenetic path analysis. We find that relative slowdowns in diversification rates characterize families that have accumulated large numbers of co-occurring species (at the 1° scale) within restricted geographical areas. Conversely, more constant diversification through time is prevalent among families in which species show limited range overlap. Relative co-occurrence is itself also a strong predictor of ecological divergence (here approximated by morphological divergence among species); however, once the relationship between co-occurrence and diversification rates have been accounted for, increased ecological divergence is an additional explanatory factor accounting for why some lineages continue to diversify towards the present. We conclude that opportunities for prolonged diversification are predominantly determined by continued geographical range expansion and to a lesser degree by ecological divergence among lineages.
Clonal evolution and genome stability in a 2500-year-old fungal individual
Authors: Anderson James B. , Bruhn Johann N. , Kasimer Dahlia , Wang Hao , Rodrigue Nicolas , Smith Myron L.
Published: December 2018

Individuals of the basidiomycete fungus
Armillaria
are well known for their ability to spread from woody substrate to substrate on the forest floor through the growth of rhizomorphs. Here, we made 248 collections of
A. gallica
in one locality in Michigan's Upper Peninsula. To identify individuals, we genotyped collections with molecular markers and somatic compatibility testing. We found several different individuals in proximity to one another, but one genetic individual stood out as exceptionally large, covering hundreds of tree root systems over approximately 75 hectares of the forest floor. Based on observed growth rates of the fungus, we estimate the minimum age of the large individual as 2500 years. With whole-genome sequencing and variant discovery, we also found that mutation had occurred within the somatic cells of the individual, reflecting its historical pattern of growth from a single point. The overall rate of mutation over the 90 mb genome, however, was extremely low. This same individual was first discovered in the late 1980s, but its full spatial extent and internal mutation dynamic was unknown at that time. The large individual of
A. gallica
has been remarkably resistant to genomic change as it has persisted in place.
Impact of immune activation on stored sperm viability in ant queens
Authors: Chérasse Sarah , Aron Serge
Published: December 2018

Ant queens mate on a single occasion early in life and store millions of sperm cells in their spermatheca. By carefully using stored sperm to fertilize eggs, they can produce large colonies of thousands of individuals. Queens can live for decades and their lifetime reproductive success is dependent on their ability to keep stored sperm alive. Maintaining high sperm viability requires metabolic energy which could trade-off with other costly processes such as immunity. We tested the impact of immune activation on the survival of stored sperm by prompting
Lasius niger
ant queens to mount a melanization response and subsequently measuring sperm viability in their spermatheca. Since queens face different challenges that influence energy allocation depending on the life stage of their colony, we measured sperm viability after immune activation in both newly mated queens (incipient) and in queens 1 year after mating (established). We found that immune activation reduced sperm viability in established queens but not in incipient queens, showing that the cost of immunity on sperm preservation depends on the life stage. Unexpectedly, established queens had significantly higher sperm viability in their spermatheca compared to incipient queens suggesting that ant queens are able to remove dead sperm from their spermatheca.
Divergent selection on the biomechanical properties of stamens under wind and insect pollination
Authors: Timerman David , Barrett Spencer C. H.
Published: December 2018

Wind pollination has evolved from insect pollination in numerous angiosperm lineages and is associated with a characteristic syndrome of morphological traits. The traits initiating transitions to wind pollination and the ecological drivers involved are poorly understood. Here, we examine this problem in
Thalictrum pubescens
, an ambophilous (insect and wind pollination) species that probably represents a transitional state in the evolution of wind pollination. We investigated wind-induced pollen release by forced harmonic motion by measuring stamen natural frequency (

f
n

), a key vibration parameter, and its variability among nine populations. We assessed the repeatability of

f
n

over consecutive growing seasons, the effect of this parameter on pollen release in a wind tunnel, and male reproductive success in the field using experimental manipulation of the presence or absence of pollinators. We found significant differences among populations and high repeatability within genotypes in

f
n

. The wind tunnel assay revealed a strong negative correlation between

f
n

and pollen release. Siring success was greatest for plants with lower

f
n

when pollinators were absent, but this advantage diminished when pollinators were present. Our biomechanical analysis of the wind–flower interface has identified

f
n

as a key trait for understanding early stages in the transition from insect to wind pollination.