bluuebunny/crossref_metadata_2025 huggingface dataset:
Salutary Effects of the PULVAD, a Novel Implantable Counterpulsation Assist Device, on Cardiac Mechanoenergetics
Authors: Kontogiannis Christos , Aravantinos Dionysios , Nanas Ioannis , Kapelios Chris J. , Marinakis Sotirios , Vakrou Styliani , Sarchosi Smaragdi , Perrea Despina N. , Mason Jay W. , Nanas John N. , Malliaras Konstantinos
Published: June 2018

The Pressure Unloading Left Ventricular Assist Vevice (PULVAD) is a novel implantable counterpulsation LVAD, designed to provide ventricular unloading with augmentation of LV performance and retention of pulsatility. We assessed the effects of the PULVAD on hemodynamics and LV mechanoenergetics in seven farm pigs with acute ischemic heart failure. The PULVAD was implanted in the thorax and was connected to the ascending aorta. The PULVAD was pneumatically driven by a standard intra-aortic balloon pump console and was electrocardiogram-synchronized to provide LV pressure unloading along with diastolic aortic pressure augmentation. Hemodynamics, indices of LV mechanoenergetics, and coronary blood flow were measured without and after brief PULVAD support. PULVAD support decreased LV afterload and improved LV mechanical performance (increased ejection fraction, stroke volume, cardiac output and maximum elastance). The PULVAD concurrently reduced LV energy consumption (decreased stroke work and pressure–volume area) and optimized LV energetic performance (improved the ratio of stroke work to pressure–volume area). PULVAD support increased mean coronary blood flow, through dramatic augmentation of diastolic blood flow. In conclusion, the PULVAD unloads the failing LV, optimizes LV mechanoenergetics, and augments coronary blood flow. These salutary effects of short-term PULVAD support provide the foundation for long-term testing.
Physiology of Transcranial Direct Current Stimulation
Authors: Stagg Charlotte J. , Antal Andrea , Nitsche Michael A.
Published: June 2018

Direct current stimulation is a neuromodulatory noninvasive brain stimulation tool, which was first introduced in animal and human experiments in the 1950s, and added to the standard arsenal of methods to alter brain physiology as well as psychological, motor, and behavioral processes and clinical symptoms in neurological and psychiatric diseases about 20 years ago. In contrast to other noninvasive brain stimulation tools, such as transcranial magnetic stimulation, it does not directly induce cerebral activity, but rather alters spontaneous brain activity and excitability by subthreshold modulation of neuronal membranes. Beyond acute effects on brain functions, specific protocols are suited to induce long-lasting alterations of cortical excitability and activity, which share features with long-term potentiation and depression. These neuroplastic processes are important foundations for various cognitive functions such as learning and memory formation and are pathologically altered in numerous neurological and psychiatric diseases. This explains the increasing interest to investigate transcranial direct current stimulation (tDCS) as a therapeutic tool. However, for tDCS to be used effectively, it is crucial to be informed about physiological mechanisms of action. These have been increasingly elucidated during the last years. This review gives an overview of the current knowledge available regarding physiological mechanisms of tDCS, spanning from acute regional effects, over neuroplastic effects to its impact on cerebral networks. Although knowledge about the physiological effects of tDCS is still not complete, this might help to guide applications on a scientifically sound foundation.
Macroevolutionary consequences of sexual conflict
Authors: Hermansen Jo S. , Starrfelt Jostein , Voje Kjetil L. , Stenseth Nils C.
Published: June 2018

Intralocus sexual conflicts arise whenever the fitness optima for a trait expressed in both males and females differ between the sexes and shared genetic architecture constrains the sexes from evolving independently towards their respective optima. Such sexual conflicts are commonplace in nature, yet their long-term evolutionary consequences remain unexplored. Using a Bayesian phylogenetic comparative framework, we studied the macroevolutionary dynamics of intersexual trait integration in stalk-eyed flies (Diopsidae) spanning a time frame of more than 25 Myr. We report that increased intensity of sexual selection on male eyestalks is associated with reduced intersexual eyestalk integration, as well as sex-specific rates of eyestalk evolution. Despite this, lineages where males have been under strong sexual selection for millions of years still exhibit high levels of intersexual trait integration. This low level of decoupling between the sexes may indicate that exaggerated female eyestalks are in fact adaptive—or alternatively, that there are strong constraints on reducing trait integration between the sexes. Future work should seek to clarify the relative roles of constraints and selection in contributing to the varying levels of intersexual trait integration in stalk-eyed flies, and in this way clarify whether sexual conflicts can act as constraints on adaptive evolution even on macroevolutionary time scales.
The perils of paradise: an endangered species conserved on an island loses antipredator behaviours within 13 generations
Authors: Jolly Chris J. , Webb Jonathan K. , Phillips Ben L.
Published: June 2018

When imperilled by a threatening process, the choice is often made to conserve threatened species on offshore islands that typically lack the full suite of mainland predators. While keeping the species extant, this releases the conserved population from predator-driven natural selection. Antipredator traits are no longer maintained by natural selection and may be lost. It is implicitly assumed that such trait loss will happen slowly, but there are few empirical tests. In Australia, northern quolls (
Dasyurus hallucatus
) were moved onto a predator-free offshore island in 2003 to protect the species from the arrival of invasive cane toads on the mainland. We compared the antipredator behaviours of wild-caught quolls from the predator-rich mainland with those from this predator-free island. We compared the responses of both wild-caught animals and their captive-born offspring, to olfactory cues of two of their major predators (feral cats and dingoes). Wild-caught, mainland quolls recognized and avoided predator scents, as did their captive-born offspring. Island quolls, isolated from these predators for only 13 generations, showed no recognition or aversion to these predators. This study suggests that predator aversion behaviours can be lost very rapidly, and that this may make a population unsuitable for reintroduction to a predator-rich mainland.
Control of human gait stability through foot placement
Authors: Bruijn Sjoerd M. , van Dieën Jaap H.
Published: June 2018

During human walking, the centre of mass (CoM) is outside the base of support for most of the time, which poses a challenge to stabilizing the gait pattern. Nevertheless, most of us are able to walk without substantial problems. In this review, we aim to provide an integrative overview of how humans cope with an underactuated gait pattern. A central idea that emerges from the literature is that foot placement is crucial in maintaining a stable gait pattern. In this review, we explore this idea; we first describe mechanical models and concepts that have been used to predict how foot placement can be used to control gait stability. These concepts, such as for instance the extrapolated CoM concept, the foot placement estimator concept and the capture point concept, provide explicit predictions on where to place the foot relative to the body at each step, such that gait is stabilized. Next, we describe empirical findings on foot placement during human gait in unperturbed and perturbed conditions. We conclude that humans show behaviour that is largely in accordance with the aforementioned concepts, with foot placement being actively coordinated to body CoM kinematics during the preceding step. In this section, we also address the requirements for such control in terms of the sensory information and the motor strategies that can implement such control, as well as the parts of the central nervous system that may be involved. We show that visual, vestibular and proprioceptive information contribute to estimation of the state of the CoM. Foot placement is adjusted to variations in CoM state mainly by modulation of hip abductor muscle activity during the swing phase of gait, and this process appears to be under spinal and supraspinal, including cortical, control. We conclude with a description of how control of foot placement can be impaired in humans, using ageing as a primary example and with some reference to pathology, and we address alternative strategies available to stabilize gait, which include modulation of ankle moments in the stance leg and changes in body angular momentum, such as rapid trunk tilts. Finally, for future research, we believe that especially the integration of consideration of environmental constraints on foot placement with balance control deserves attention.
Microstructure and mechanical properties of different keratinous horns
Authors: Zhang Yuchen , Huang Wei , Hayashi Cheryl , Gatesy John , McKittrick Joanna
Published: June 2018

Animal horns play an important role during intraspecific combat. This work investigates the microstructure and mechanical properties of horns from four representative ruminant species: the bighorn sheep (Ovis canadensis), domestic sheep (Ovis aries), mountain goat (Oreamnos americanus) and pronghorn (Antilocapra americana), aiming to understand the relation between evolved microstructures and mechanical properties. Microstructural similarity is found where disc-shaped keratin cells attach edge-to-edge along the growth direction of the horn core (longitudinal direction) forming a lamella; multiple lamellae are layered face to face along the impact direction (radial direction, perpendicular to horn core growth direction), forming a wavy pattern surrounding a common feature, the tubules. Differences among species include the number and shape of the tubules, the orientation of aligned lamellae and the shape of keratin cells. Water absorption tests reveal that the pronghorn horn has the largest water-absorbing ability due to the presence of nanopores in the keratin cells. The loading direction (compressive and tensile) and level of hydration vary among the horns from different species. The differences in mechanical properties among species may relate to their different fighting behaviours: high stiffness and strength in mountain goat to support the forces during stabbing; high tensile strength in pronghorn for interlocked pulling; impact energy absorption properties in domestic and bighorn sheep to protect the skull during butting. These design rules based on evolutionary modifications among species can be applied in synthetic materials to meet different mechanical requirements.
Cancer immunotherapy: broadening the scope of targetable tumours
Authors: van den Bulk Jitske , Verdegaal Els ME , de Miranda Noel FCC
Published: June 2018

Cancer immunotherapy has experienced remarkable advances in recent years. Striking clinical responses have been achieved for several types of solid cancers (e.g. melanoma, non-small cell lung cancer, bladder cancer and mismatch repair-deficient cancers) after treatment of patients with T-cell checkpoint blockade therapies. These have been shown to be particularly effective in the treatment of cancers with high mutation burden, which places tumour-mutated antigens (neo-antigens) centre stage as targets of tumour immunity and cancer immunotherapy. With current technologies, neo-antigens can be identified in a short period of time, which may support the development of complementary, personalized approaches that increase the number of tumours amenable to immunotherapeutic intervention. In addition to reviewing the state of the art in cancer immunotherapy, we discuss potential avenues that can bring the immunotherapy revolution to a broader patient group including cancers with low mutation burden.
The mono(catecholamine) derivatives as iron chelators: synthesis, solution thermodynamic stability and antioxidant properties research
Authors: Zhang Qingchun , Jin Bo , Wang Xiaofang , Lei Shan , Shi Zhaotao , Zhao Jia , Liu Qiangqiang , Peng Rufang
Published: June 2018

There is a growing interest in the development of new iron chelators as novel promising therapeutic strategies for neurodegenerative disorders. In this article, a series of mono(catecholamine) derivatives, 2,3-bis(hydroxy)-
N
-(hydroxyacyl)benzamide, containing a pendant hydroxy, have been synthesized and fully characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy and mass spectrum. The thermodynamic stability of the chelators with Fe
III
, Mg
II
and Zn
II
ions was then investigated. The chelators enable formation of (3 : 1) Fe
III
complexes with high thermodynamic stability and exhibited improved selectivity to Fe
III
ion. Meanwhile, the results of 1,1-diphenyl-2-picryl-hydrazyl assays of mono(catecholamine) derivatives indicated that they all possess excellent antioxidant properties. These results support the hypothesis that the mono(catecholamine) derivatives be used as high-affinity chelator for iron overload situations without depleting essential metal ions, such as Mg
II
and Zn
II
ions.
Making of a single solid-state nanopore on the wall of fused silica capillary
Authors: Fang Fang , He Yan-Qin , Tian Li , Li Yun-Yun , Wu Zhi-Yong
Published: June 2018

A channel of nanometre size is an important platform for nanofluidic investigations. In this work, we show that a single solid nanopore can be generated by hydrogen fluoride etching of the outside wall of commercially available fused silica capillary. The geometry, size and the singleness were characterized by various means, including scanning electron microscope, electrolyte conductance measurement and a fluorescent microscope. The generation principle is also discussed. The nanopore thus generated features in low aspect ratio and exhibits typical nanofluidic effects such as ion concentration polarization, rectification and molecular translocation.
Effect of Hf-doping on electrochemical performance of anatase TiO
2
as an anode material for lithium storage
Authors: Gnedenkov Sergey V. , Sinebryukhov Sergey L. , Zheleznov Veniamin V. , Opra Denis P. , Voit Elena I. , Modin Evgeny B. , Sokolov Alexander A. , Yu. Ustinov Alexander , Sergienko Valentin I.
Published: June 2018

Hafnium-doped titania (Hf/Ti = 0.01; 0.03; 0.05) had been facilely synthesized via a template sol–gel method on carbon fibre. Physico-chemical properties of the as-synthesized materials were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, scanning transmission electron microscopy, X-ray photoelectron spectroscopy, thermogravimetry analysis and Brunauer–Emmett–Teller measurements. It was confirmed that Hf
4+
substitute in the Ti
4+
sites, forming Ti

1–
x

Hf

x

O
2
(
x
 = 0.01; 0.03; 0.05) solid solutions with an anatase crystal structure. The Ti

1–
x

Hf

x

O
2
materials are hollow microtubes (length of 10–100 µm, outer diameter of 1–5 µm) composed of nanoparticles (average size of 15–20 nm) with a surface area of 80–90 m
2
 g
–1
and pore volume of 0.294–0.372 cm
3
 g
–1
. The effect of Hf ion incorporation on the electrochemical behaviour of anatase TiO
2
in the Li-ion battery anode was investigated by galvanostatic charge/discharge and electrochemical impedance spectroscopy. It was established that Ti
0.95
Hf
0.05
O
2
shows significantly higher reversibility (154.2 mAh g
–1
) after 35-fold cycling at a
C
/10 rate in comparison with undoped titania (55.9 mAh g
–1
). The better performance offered by Hf
4+
substitution of the Ti
4+
into anatase TiO
2
mainly results from a more open crystal structure, which has been achieved via the difference in ionic radius values of Ti
4+
(0.604 Å) and Hf
4+
(0.71 Å). The obtained results are in good accord with those for anatase TiO
2
doped with Zr
4+
(0.72 Å), published earlier. Furthermore, improved electrical conductivity of Hf-doped anatase TiO
2
materials owing to charge redistribution in the lattice and enhanced interfacial lithium storage owing to increased surface area directly depending on the Hf/Ti atomic ratio have a beneficial effect on electrochemical properties.
Multi-scale investigation of the formation and properties of high-grade rutile TiO
2
from titanium slags using microwave heating
Authors: Chen Guo , Pu Jing , Chen Jin , Peng Jinhui , Srinivasakannan C. , Ruan Rongsheng
Published: June 2018

In this paper, the phase transition of titanium slag under microwave heating observed through electron microscopy was systematically investigated. The phase identification and transformation as well as the morphology of samples before and after each treatment were characterized using X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM). The XRD confirmed that sodium salt roasting could modify the phase composition of titanium slag. The microwave roasting in the presence of sodium salt increased the rutile TiO
2
with high crystallinity after acid leaching. The Raman spectroscopy demonstrated the phase transition of titanium slag from anosovite to rutile TiO
2
after a series of treatments, and the SEM analyses showed that the surface of calcined products grew plenty of rutile TiO
2
with typical characteristics. The results indicate a successful process for an effective and efficient way for the utilization of both titanium slag and preparation of rutile TiO
2
.
Synthesis and characterization of Zr- and Hf-doped nano-TiO
2
as internal standards for analytical quantification of nanomaterials in complex matrices
Authors: Ellis Laura-Jayne A. , Papadiamantis Anastasios G. , Weigel Stefan , Valsami-Jones Eugenia
Published: June 2018

The reliable quantification of nanomaterials (NMs) in complex matrices such as food, cosmetics and biological and environmental compartments can be challenging due to interactions with matrix components and analytical equipment (vials and tubing). The resulting losses along the analytical process (sampling, extraction, clean-up, separation and detection) hamper the quantification of the target NMs in these matrices as well as the compatibility of results and meaningful interpretations in safety assessments. These issues can be overcome by the addition of known amounts of internal/recovery standards to the sample prior to analysis. These standards need to replicate the behaviour of target analytes in the analytical process, which is mainly defined by the surface properties. Moreover, they need to carry a tag that can be quantified independently of the target analyte. As inductively coupled plasma mass spectrometry is used for the identification and quantification of NMs, doping with isotopes, target analytes or with chemically related rare elements is a promising approach. We present the synthesis of a library of TiO
2
NMs doped with hafnium (Hf) and zirconium (Zr) (both low in environmental abundance). Zirconia NMs doped with Hf were also synthesized to complement the library. NMs were synthesized with morphological and size properties similar to commercially available TiO
2
. Characterization included: transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, Brunauer–Emmett–Teller total specific surface area analysis, cryofixation scanning electron microscopy, inductively coupled plasma optical emission spectroscopy and UV–visible spectrometry. The Ti : Hf and Ti : Zr ratios were verified and calculated using Rietveld refinement. The labelled NMs can serve as internal standards to track the extraction efficiency from complex matrices, and increase method robustness and traceability of characterization/quantification.
Thickness-dependent humidity sensing by poly(vinyl alcohol) stabilized Au–Ag and Ag–Au core–shell bimetallic nanomorph resistors
Authors: Adhyapak Parag , Aiyer Rohini , Dugasani Sreekantha Reddy , Kim Hyeong-U , Song Chung Kil , Vinu Ajayan , Renugopalakrishnan Venkatesan , Park Sung Ha , Kim Taesung , Lee Haiwon , Amalnerkar Dinesh
Published: June 2018

We herein report a simple chemical route to prepare Au–Ag and Ag–Au core–shell bimetallic nanostructures by reduction of two kinds of noble metal ions in the presence of a water-soluble polymer such as poly(vinyl alcohol) (PVA). PVA was intentionally chosen as it can play a dual role of a supporting matrix as well as stabilizer. The simultaneous reduction of metal ions leads to an alloy type of structure. Ag(c)–Au(s) core–shell structures display tendency to form prismatic nanostructures in conjunction with nanocubes while Au(c)–Ag(s) core–shell structures show formation of merely nanocubes. Although UV–visible spectroscopy and X-ray photoelectron spectroscopy analyses of the samples typically suggest the formation of both Ag(c)–Au(s) and Au(c)–Ag(s) bimetallic nanostructures, the definitive evidence comes from high-resolution transmission electron microscopy–high-angle annular dark field elemental mapping in the case of Au(c)–Ag(s) nanomorphs only. The resultant nanocomposite materials are used to fabricate resistors on ceramic rods having two electrodes by drop casting technique. These resistors are examined for their relative humidity (RH) response in the range (2–93% RH) and both the bimetallic nanocomposite materials offer optimized sensitivity of about 20 Kohm/% RH and 300 ohm/% RH at low and higher humidity conditions, respectively, which is better than that of individual nanoparticles.
The high-level basis of body adaptation
Authors: Brooks Kevin R. , Clifford Colin W. G. , Stevenson Richard J. , Mond Jonathan , Stephen Ian D.
Published: June 2018

Prolonged visual exposure, or ‘adaptation’, to thin (wide) bodies causes a perceptual aftereffect such that subsequently seen bodies appear wider (thinner) than they actually are. Here, we conducted two experiments investigating the effect of rotating the orientation of the test stimuli by 90° from that of the adaptor. Aftereffects were maximal when adapting and test bodies had the same orientation. When they differed, the axis of the perceived distortion changed with the orientation of the body. Experiment 1 demonstrated a 58% transfer of the aftereffect across orientations. Experiment 2 demonstrated an even greater degree of aftereffect transfer when the influence of low-level mechanisms was reduced further by using adaptation and test stimuli with different sizes. These results indicate that the body aftereffect is mediated primarily by high-level object-based processes, with low-level retinotopic mechanisms playing only a minor role. The influence of these low-level processes is further reduced when test stimuli differ in size from adaptation stimuli.
The behaviour of overweight dogs shows similarity with personality traits of overweight humans
Authors: Pogány Ákos , Torda Orsolya , Marinelli Lieta , Lenkei Rita , Junó Vanda , Pongrácz Péter
Published: June 2018

Excessive food intake and the resulting excess weight gain is a growing problem in human and canine populations. Dogs, due to their shared living environment with humans, may provide a beneficial model to study the causes and consequences of obesity. Here, we make use of two well-established research paradigms (two-way choice paradigm and cognitive bias test), previously applied with dogs, to investigate the role of obesity and obesity-prone breeds for food responsiveness. We found no evidence of breed differences in food responsiveness due to one breed being more prone to obesity than another. Breed differences found in this study, however, can be explained by working dog status, i.e. whether the dog works in cooperation with, or independently from, humans. Our results also confirm that overweight dogs, as opposed to normal weight dogs, tried to maximize food intake from the higher quality food and hesitated to do the task when the food reward was uncertain. These results are very similar to those expected from the parallel models that exist between certain personality traits and being overweight in humans, suggesting that dogs are indeed a promising model for experimentally investigating obesity in humans.
Sensing study of quinoxaline analogues with theoretical calculation, single-crystal X-ray structure and real application in commercial fruit juices
Authors: Chakraborty Shampa , Goswami Shyamaprosad , Quah Ching Kheng , Pakhira Bholanath
Published: June 2018

Single-crystal X-ray structures of dimeric quinoxaline aldehyde (QA), quinoxaline dihydrazone (DHQ) and HQNM (Goswami S
et al.
2013
Tetrahedron Lett.
54
, 5075–5077. (
doi:10.1016/j.tetlet.2013.07.051
); Goswami S
et al.
2014
RSC Adv.
4
, 20 922–20 926. (
doi:10.1039/C4RA00594E
); Goswami S
et al.
2014
New J. Chem.
38
, 6230–6235. (
doi:10.1039/C4NJ01498G
)) are reported along with the theoretical study. Among them, QA is not acting as an active probe, but DHQ and HQNM are serving as selective and sensitive probe for the Fe
3+
cation and the Ni
2+
cation, respectively. DHQ can also detect the Fe
3+
in commercial fruit juices (grape and pomegranate).
How silanization influences aggregation and moisture sorption behaviours of silanized silica: analysis of porosity and multilayer moisture adsorption
Authors: Jiang Jun , Cao Jinzhen , Wang Wang , Xue Jing
Published: June 2018

Based on the results of nitrogen adsorption and dynamic vapour sorption as well as analysis by the Hailwood–Horrobin (H-H) model, the effects of γ-methacryloxypropyltrimethoxysilane (MPTS) on the agglomeration and moisture sorption properties of fumed silica particles were investigated. After adding various concentrations (2%, 4%, 6% and 8%) of MPTS, different degrees of silanization were obtained by showing various ─OH group contents on the silica surface, which resulted in silica agglomerates with different porous structures. The bigger mesopores in the unmodified silica agglomerates became smaller and finally disappeared after MPTS modification and the Bruanuer–Emmett–Teller surface area decreased more gradually with an increase in MPTS concentration. The H-H model fitted the sorption isotherms very well, and both hydrated water and dissolved water showed decreasing trends with the increase in MPTS concentration, showing reduced hygroscopicity. Up to 6% MPTS, the ─OH groups decreased with increasing MPTS concentration, as indicated by reduced
K
h
and
W
parameters, while at 8% MPTS an extensive self-condensation of MPTS occurred. Adsorption hysteresis appeared for moisture sorption on silanized silica, especially at low relative humidity values and at low MPTS concentrations, which could be explained by a synergistic effect of the surface ─OH group content and pore characteristics. These results could aid our understanding of the applications of silane-modified silica particles.
Male monkeys use punishment and coercion to de-escalate costly intergroup fights
Authors: Arseneau-Robar T. Jean M. , Müller Eliane , Taucher Anouk L. , van Schaik Carel P. , Bshary Redouan , Willems Erik P.
Published: June 2018

In numerous social species, males direct aggression towards female group members during intergroup fights, and this behaviour is commonly thought to function as mate guarding, even though males often target non-receptive females. In studying intergroup fights in a wild population of vervet monkeys, we found that male intragroup aggression was primarily directed towards individuals who had either just finished exhibiting, or were currently attempting to instigate intergroup aggression. Targeted females were less likely to instigate intergroup aggression in the future, indicating that male intragroup aggression functioned as coercion (when directed towards those who were currently trying to instigate a fight) and punishment (when directed towards those who had recently fought). These manipulative tactics effectively prevented intergroup encounters from escalating into fights and often de-escalated ongoing conflicts. Males who were likely sires were those most likely to use punishment/coercion, particularly when they were wounded, and, therefore, less able to protect vulnerable offspring should a risky intergroup fight erupt. This work, along with our previous finding that females use punishment and rewards to recruit males into participating in intergroup fights, highlights the inherent conflict of interest that exists between the sexes, as well as the role that social incentives can play in resolving this conflict. Furthermore, unlike other studies which have found punishment to be used asymmetrically between partners, these works represent a novel example of reciprocal punishment in a non-human animal.
Urban rat races: spatial population genomics of brown rats (
Rattus norvegicus
) compared across multiple cities
Authors: Combs Matthew , Byers Kaylee A. , Ghersi Bruno M. , Blum Michael J. , Caccone Adalgisa , Costa Federico , Himsworth Chelsea G. , Richardson Jonathan L. , Munshi-South Jason
Published: June 2018

Urbanization often substantially influences animal movement and gene flow. However, few studies to date have examined gene flow of the same species across multiple cities. In this study, we examine brown rats (
Rattus norvegicus
) to test hypotheses about the repeatability of neutral evolution across four cities: Salvador, Brazil; New Orleans, USA; Vancouver, Canada; and New York City, USA. At least 150 rats were sampled from each city and genotyped for a minimum of 15 000 genome-wide single nucleotide polymorphisms. Levels of genome-wide diversity were similar across cities, but varied across neighbourhoods within cities. All four populations exhibited high spatial autocorrelation at the shortest distance classes (less than 500 m) owing to limited dispersal. Coancestry and evolutionary clustering analyses identified genetic discontinuities within each city that coincided with a resource desert in New York City, major waterways in New Orleans, and roads in Salvador and Vancouver. Such replicated studies are crucial to assessing the generality of predictions from urban evolution, and have practical applications for pest management and public health. Future studies should include a range of global cities in different biomes, incorporate multiple species, and examine the impact of specific characteristics of the built environment and human socioeconomics on gene flow.
‘Green incubation': avian offspring benefit from aromatic nest herbs through improved parental incubation behaviour
Authors: Gwinner Helga , Capilla-Lasheras Pablo , Cooper Caren , Helm Barbara
Published: June 2018

Development of avian embryos requires thermal energy, usually from parents. Parents may, however, trade off catering for embryonic requirements against their own need to forage through intermittent incubation. This dynamically adjusted behaviour can be affected by properties of the nest. Here, we experimentally show a novel mechanism by which parents, through incorporation of aromatic herbs into nests, effectively modify their incubation behaviour to the benefit of their offspring. Our study species, the European starling, includes in its nest aromatic herbs which promote offspring fitness. We provided wild starlings with artificial nests including or excluding the typically selected fresh herbs and found strong support for our prediction of facilitated incubation. Herb effects were not explained by thermal changes of the nests
per se
, but by modified parental behaviours. Egg temperatures and nest attendance were higher in herb than herbless nests, egg temperatures dropped less frequently below critical thresholds and parents started their active day earlier. These effects were dynamic over time and particularly strong during early incubation. Incubation period was shorter in herb nests, and nestlings were heavier one week after hatching. Aromatic herbs hence influenced incubation in beneficial ways for offspring, possibly through pharmacological effects on incubating parents.
Exaggerated male legs increase mating success by reducing disturbance to females in the cave wētā
Pachyrhamma waitomoensis
Authors: Fea Murray , Holwell Gregory I.
Published: June 2018

Mate guarding is a widespread behaviour resulting from sperm competition and conflict over optimal remating rates. It is a key way in which males exhibit differential mating investment, and represents a complex interplay between mating effort, intrasexual competition, opportunity costs and sexual conflict. Nevertheless, although there are many examples of exaggerated male structures used to fight rivals, few animals have developed specialized male morphological adaptations for directly sheltering females from disturbance by non-rivals. Here we report on the use of sexually dimorphic, elongated male hind legs, which are used to guard females in the New Zealand cave wētā
Pachyrhamma waitomoensis
(Orthoptera: Rhaphidophoridae). We found that male hind legs alongside the female failed to deter rivals from accessing her or disrupting copulation. However, they did reduce the disturbance to females from other, non-rival animals such as juveniles and heterospecifics. Males with longer hind legs were more effective in reducing disturbance, and remained with females for longer. Longer guarding periods also led to higher numbers of matings between pairs. Models of males with artificially altered hind leg dimensions also showed a benefit to greater leg length, and artificially altering the disturbance rate to females also had a significant effect on pair duration. Our results indicate that nuisance disturbance to females may play an important role in driving sexual selection on male leg length and its exaggeration in this species.
True recognition of nestlings by hosts selects for mimetic cuckoo chicks
Authors: Noh Hee-Jin , Gloag Ros , Langmore Naomi E.
Published: June 2018

Brood parasitic cuckoos lay their eggs in other birds' nests, whereafter the young cuckoo hatches, ejects its nest-mates and monopolizes the care of the host parents. Theory predicts that hosts should not evolve to recognize and reject cuckoo chicks via imprinting because of the risk of mistakenly imprinting on a cuckoo chick in their first brood and thereafter always rejecting their own chicks. However, recent studies have revealed that some hosts do reject cuckoo chicks from the nest, indicating that these hosts’ recognition systems either do not rely on first brood imprinting, or use cues that are independent of chick phenotype. Here, we investigate the proximate mechanisms of chick rejection behaviour in the large-billed gerygone (Gerygone magnirostris), a host of the little bronze-cuckoo (Chalcites minutillus). We find that gerygones use true template-based recognition based on at least one visual chick trait (the number of hatchling down-feathers), and that this is further mediated by experience of adult cuckoos at the nest during egg-laying. Given the theoretical constraints of acquiring recognition templates via imprinting, gerygones must possess a template of own-chick appearance that is largely innate. This true recognition has facilitated the evolution of very rapid hatchling rejection and, in turn, striking visual mimicry of host young by little bronze-cuckoo chicks.
CETP inhibition and ADCY9 genotype: evidence of a qualitative pharmacogenetic interaction in cardiovascular disease?
Authors: Holmes Michael V , Davey Smith George
Published: June 2018

Background

CETP inhibitors raise circulating concentrations of HDL-cholesterol, and potent inhibitors also lower non-HDL-cholesterol and risk of vascular disease. Previous genome-wide pharmacogenetic analysis of a phase III randomized controlled trial (RCT) of the CETP inhibitor, dalcetrapib, found variants in ADCY9 to associate with response to treatment. More recently, findings from a pharmacogenetic analysis of the CETP inhibitor evacetrapib reported a lack of such an association.

Aims

To clarify the totality of evidence on whether ADCY9 genotype modifies the treatment response to CETP inhibition on risk of major adverse cardiac events through systematic review and meta-analysis.

Methods

We searched PubMed on 22nd May 2018 to identify RCTs of CETP inhibition that reported vascular disease effect estimates stratified by ADCY9 genotype. Stratum-specific estimates were pooled using fixed effect meta-analysis. Tests of heterogeneity between, and trend across, genotypic strata were assessed using Chi2.

Results

Nine studies were identified from PubMed, of which two (dal-OUTCOMES and ACCELERATE) were RCTs reporting the treatment response to CETP inhibition by ADCY9 genotype, and fulfilled the inclusion criteria. In meta-analysis of dal-OUTCOMES and ACCELERATE, treatment with a CETP inhibitor was associated with a relative risk (RR) for major adverse cardiac events of RR 0.80 (95%CI, 0.65-0.99) in carriers of ADCY9 rs1967309 AA. For carriers of AG, the corresponding estimate was a RR of 1.01 (95%CI, 0.89-1.13), and for GG carriers, it was RR 1.21 (95%CI, 1.06-1.40). We identified evidence of heterogeneity (P=0.004) and a trend (P=0.0009) across genotypic groups.

Conclusions

In contrast to the interpretation provided by authors of the analysis based in the ACCELERATE trial, the available evidence lends weak support to a potential interaction of CETP treatment by ADCY9 genotype on risk of major adverse cardiac events. Additional data, e.g. from the ongoing dal-GenE trial focused explicitly on this interaction, should provide further clarity regarding the robustness of this pharmacogenetic effect.
Biochemical, molecular and antibiotic resistance profile of multi-potential toluene metabolizing bacteria isolated from tannery effluents
Authors: Muccee Fatima , Ejaz Samina
Published: June 2018

The focus of present study was to isolate and characterize bacteria which can be effectively used for toluene, a highly recalcitrant pollutant, bioremediation. For isolation of bacteria from the tannery effluents selective enrichment and serial dilution methods were employed. The isolated bacteria were subjected to growth curve analysis, estimation of toluene removal efficiencies, biochemical tests, antibiotic sensitivity assays and molecular characterization based upon 16S rRNA gene. The rRNA genes sequences were analyzed through BLAST to determine similarity index of isolates with bacterial database sequences. To trace the evolutionary history, phylogenetic trees were constructed using MEGA version 7. Total twenty toluene metabolizing bacteria (IUBT1-2, 4-12, 16, 19, 21, 23-26, 28 and 30) were isolated and characterized. Their rRNA gene sequences have been submitted to Genbank. Fifteen of the twenty isolates showed homology toBrevibacillus agristrain NBRC 15538, four found similar toBacillus paralicheniformisstrain KJ-16 and one homologous toBurkholderia latastrain 383. All bacterial isolates were resistant to chloramphenicol but sensitive to teicoplanin and linezolid. However, few (i. e.; IUBT9 and 26) were sensitive to oxacillin. Biochemical characterization indicated all bacteria positive for alkaline phosphatases (100%). While many were found positive for p-nitrophenyl N-acetyl β, D-glucosaminidase (35%), hydroxyproline β-naphthylaminopeptidase (15%), esculinase (65%), mannitol (75%), sorbitol (95%) and inulin (90%) fermentation. Biochemical profile suggests the use of isolated bacteria for future exploitation in several fields like bioremediation of toluene, ethanol production, biomass hydrolysis, biosensors, biofertilizers, as a marker for milk pasteurization in dairy industries and evaluation of soil quality.

Importance

Toluene is a highly toxic environmental pollutant. We have isolated bacteria which can be effectively used for the removal of toluene from environmental resources. Moreover, these bacteria are capable to produce many valuable enzymes which can be used in many industrial processes for the production of a wide range of products. Further study may help to exploit these bacterial for the benefit of humanity.
Early split between African and European populations of Drosophila melanogaster
Authors: Kapopoulou Adamandia , Kapun Martin , Pavlidis Pavlos , Pieper Bjorn , Wilches Ricardo , Stephan Wolfgang , Laurent Stefan
Published: June 2018

Natural populations of the fruit fly Drosophila melanogaster have been used extensively as a model system to investigate the effect of neutral and selective processes on genetic variation. The species expanded outside its Afrotropical ancestral range during the last glacial period and numerous studies have focused on identifying molecular adaptations associated with the colonization of northern habitats. The sequencing of many genomes from African and non-African natural populations has facilitated the analysis of the interplay between adaptive and demographic processes. However, most of the non-African sequenced material has been sampled from American and Australian populations that have been introduced within the last hundred years following recent human dispersal and are also affected by recent genetic admixture with African populations. Northern European populations, at the contrary, are expected to be older and less affected by complex admixture patterns and are therefore more appropriate to investigate neutral and adaptive processes. Here we present a new dataset consisting of 14 fully sequenced haploid genomes sampled from a natural population in Umeå, Sweden. We co-analyzed this new data with an African population to compare the likelihood of several competing demographic scenarios for European and African populations. We show that allowing for gene flow between populations in neutral demographic models leads to a significantly better fit to the data and strongly affects estimates of the divergence time and of the size of the bottleneck in the European population. Our results indicate that the time of divergence between cosmopolitan and ancestral populations is 30,000 years older than reported by previous studies.
Metaproteomics Reveals Potential Mechanisms by which Dietary Resistant Starch Supplementation Attenuates Chronic Kidney Disease Progression in Rats
Authors: Zybailov Boris L , Glazko Galina V , Rahmatallah Yasir , Andreyev Dmitri S , McElroy Taylor , Karaduta Oleg , Byrum Stephanie D , Orr Lisa , Tackett Alan J , Mackintosh Samuel G , Edmondson Ricky D , Kieffer Dorothy A , Martin R J , Adams Sean H , Vaziri Nicolas D , Arthur John M
Published: June 2018

Background

Resistant starch is a prebiotic metabolized by the gut bacteria. It has been shown to attenuate chronic kidney disease (CKD) progression in rats. Previous studies employed taxonomic analysis using 16S rRNA sequencing and untargeted metabolomics profiling. Here we expand these studies by metaproteomics, gaining new insight into the host-microbiome interaction.

Methods

Differences between cecum contents in CKD rats fed a diet containing resistant starch with those fed a diet containing digestible starch were examined by comparative metaproteomics analysis. Taxonomic information was obtained using unique protein sequences. Our methodology results in quantitative data covering both host and bacterial proteins.

Results

5,834 proteins were quantified, with 947 proteins originating from the host organism. Taxonomic information derived from metaproteomics data surpassed previous 16S RNA analysis, and reached species resolutions for moderately abundant taxonomic groups. In particular, the Ruminococcaceae family becomes well resolved – with butyrate producers and amylolytic species such as R. bromii clearly visible and significantly higher while fibrolytic species such as R. flavefaciens are significantly lower with resistant starch feeding. The observed changes in protein patterns are consistent with fiber-associated improvement in CKD phenotype. Several known host CKD-associated proteins and biomarkers of impaired kidney function were significantly reduced with resistant starch supplementation. Data are available via ProteomeXchange with identifier PXD008845.

Conclusions

- Metaproteomics analysis of cecum contents of CKD rats with and without resistant starch supplementation reveals changes within gut microbiota at unprecedented resolution, providing both functional and taxonomic information. Proteins and organisms differentially abundant with RS supplementation point toward a shift from mucin degraders to butyrate producers.
Association of theGIPRGlu354Gln (rs1800437) polymorphism with hypertension in a brazilian population
Authors: Mattos Alexandro Marcio da Silva , Costa Sarah Conchon , Outuki Giovana , Koga Gustavo Kendy Camargo , Montemor Cláudia Nascimento , Longo Giana Zarbato , Watanabe Maria Angelica Ehara , Amarante Marla Karine , Mazzuco Tânia Longo
Published: June 2018

Objective

To know the prevalence of the Glu354Gln polymorphism of theGIPRgene, investigate possible associations with arterial hypertension and relationships with cardiometabolic diseases.

Method

A total of 311 subjects recruited from the Clinical Hospital of Londrina State University, located in a Brazilian metropolitan area. Random stratification was performed considering gender and geographic regions. Data were collected through interviews including anthropometric, sociodemographic and metabolic diseases related diseases. In order to analyzeGIPRGlu354Gln gene polymorphism, polymerase chain reaction followed by followed by restriction fragment length polymorphism (PCR-RFLP) was performed.

Results

The highest prevalence for the allele C carriers were found in the Caucasian 29.4% (p = 0.043, OR = 1,89), hypertensive 37.1% (p < 0.0001), smokers 38.3% (p = 0.014) and dyslipidemic group 41.2% (p = 0.019). In this work 46.9% of the participants (n = 146) presented diseases related to cardiometabolic diseases. The results indicated that 60% of hypertensive patients (p = 0.004) and 64.7% of dyslipidemic patients (p = 0.046) were male. Among participants who presented cardiometabolic diseases, arterial hypertension was the most prevalent disease (71.9%), followed by obesity (43.8%). The family comorbidities history to cardiometabolic diseases (DM2, AH, dyslipidemia and obesity) had no significant association with theGIPRGlu354Gln genetic polymorphism. Although there was no difference in the case-control analyses forGIPRGlu354Gln for cardiometabolic group, regarding C allele carriers there were twice associated with arterial hypertension (p<0,001) and dyslipidemia (p<0,03).

Conclusion

The prevalence of theGIPRGlu354Gln for the CC genotype and for the C polymorphic allele was 25.7% and 3.2%, respectively. This study shows the potential participation of theGIPRGlu354Gln polymorphism with the pathophysiology of arterial hypertension, dyslipidemia in this Brazilian population. Taking into account the rarity of the CC genotype, additional studies with larger numbers of participants could contribute to a better understanding.