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Correlative imaging combines information from multiple modalities (physical–chemical–mechanical properties) at various length scales (centimetre to nanometre) to understand the complex biological materials across dimensions (2D–3D). Here, we have used numerous coupled systems: X-ray microscopy (XRM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), optical light microscopy (LM) and focused ion beam (FIB-SEM) microscopy to ascertain the microstructural and crystallographic properties of the wall-plate joints in the barnacle Semibalanus balanoides. The exoskeleton is composed of six interlocking wall plates, and the interlocks between neighbouring plates (alae) allow barnacles to expand and grow while remaining sealed and structurally strong. Our results indicate that the ala contain functionally graded orientations and microstructures in their crystallography, which has implications for naturally functioning microstructures, potential natural strengthening and preferred oriented biomineralization. Elongated grains at the outer edge of the ala are oriented perpendicularly to the contact surface, and the c-axis rotates with the radius of the ala. Additionally, we identify for the first time three-dimensional nanoscale ala pore networks revealing that the pores are only visible at the tip of the ala and that pore thickening occurs on the inside (soft bodied) edge of the plates. The pore networks appear to have the same orientation as the oriented crystallography, and we deduce that the pore networks are probably organic channels and pockets, which are involved with the biomineralization process. Understanding these multiscale features contributes towards an understanding of the structural architecture in barnacles, but also their consideration for bioinspiration of human-made materials. The work demonstrates that correlative methods spanning different length scales, dimensions and modes enable the extension of the structure–property relationships in materials to form and function of organisms.
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Context: Most papillary microcarcinomas (PMC) are indolent and subclinical, however as many as 10% can present with clinically significant nodal metastases. Objective/Design: Characterization of the genomic and transcriptomic landscape of PMC presenting with or without clinically significant lymph node metastases. Subjects/Samples: Formalin-fixed paraffin-embedded PMC samples from 40 patients with lateral neck nodal metastases (pN1b) and 71 PMC patients with documented absence of nodal disease (pN0). Outcome Measure(s): To interrogate DNA alterations in 410 genes commonly mutated in cancer and test for differential gene expression using a custom NanoString panel of 248 genes selected primarily based on their association with tumor size and nodal disease in the papillary thyroid cancer TCGA project. Results: The genomic landscapes of PMC with or without pN1b were similar. Mutations in TERT promoter (3%) and TP53 (1%) were exclusive to N1b cases. Transcriptomic analysis revealed differential expression of 43 genes in PMCs with pN1b compared to pN0. A random forest machine learning-based molecular classifier developed to predict regional lymph node metastasis demonstrated a negative predictive value of 0.98 and a positive predictive value of 0.72 at a prevalence of 10% pN1b disease. Conclusions: The genomic landscape of tumors with pN1b and pN0 disease was similar, whereas 43 genes selected primarily by mining the TCGA RNAseq data were differentially expressed. This bioinformatics-driven approach to the development of a custom transcriptomic assay provides a basis for a molecular classifier for pN1b risk stratification in PMC.
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1. Autonomous recording units are now routinely used to monitor birdsong, starting to supplement and potentially replace human listening methods. However, to date there has been very little systematic comparison of human and machine detection ability. 2. We present an experiment based on broadcast calls of nocturnal New Zealand birds in an area of natural forest. The soundscape was monitored by both novice and experienced humans performing a call count, and autonomous recording units. 3. We match records of when calls were broadcast with detections by both humans and machines, and construct a hierarchical generalised linear model of the binary variable of correct detection or not, with a set of covariates about the call (distance, sound direction, relative altitude, and line of sight) and about the listener (age, experience, and gender). 4. The results show that machines and humans have similar listening ability. Humans are more homogeneous in their recording of sounds, and this was not affected by their individual experience or characteristics. Humans were affected by trial and location, in particular one of the stations located in a small but deep valley. Despite recorders being affected significantly more than people by distance, altitude, and line of sight, their overall detection probability was higher. The specific location of recorders seems to be the most important factor determining what they record, and we suggest that for best results more than one recorder (or at least, microphone) is needed at each station to ensure all bird sounds of interest are captured.
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1. Conservation translocations are an important tool in wildlife management, but have traditionally suffered from a low success rate. Increasing understanding of animal behaviour is vital in improving the success of translocations, but few methods exist to efficiently monitor highly mobile and cryptic species post-release. 2. We present a novel approach to using dynamic occupancy modelling in combination with data derived from autonomous acoustic recording units to monitor the post-release behaviour of hihi (Notiomystis cincta), a threatened endemic bird, at a translocation site in New Zealand. The process of analysing large quantities of acoustic data was facilitated by using automated classifiers and manual validation, an approach that was both accurate and efficient. 3. We find that this approach detects behavioural change consistent with the transition from exploration of a new site to territory formation. We identify that hihi territories at the study site were closely linked to watercourses, but were not related to distance from release site. 4. We find that this method is able to effectively monitor post-release dispersal, and could provide a cost-efficient and less invasive alternative to radio-tracking for monitoring of vocal species.
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Background and Study Aims: Detecting esophageal achalasia remains a challenge. We describe the diagnostic utility of corona appearance, a novel endoscopic finding specific to esophageal achalasia. Patients and Methods: Corona appearance and seven conventional endoscopic findings were compared for sensitivity and consistency (-value) among 53 untreated esophageal achalasia patients who underwent endoscopy at our hospital. The following criteria had to be met during lower esophageal sphincter examination using the attached ST Hood short-type for positive corona appearance: A) congestion inside the hood, B) ischemic change around the hood, and C) palisade vessels outside the hood. Results: Corona appearance had the highest sensitivity (91%; -value, 0.71). Other findings in descending order of sensitivity included 1) functional stenosis of the esophagogastric junction (EGJ; 86%; -value, 0.58), 2) mucosal thickening and whitish change (71%; -value, 0.27), 3) abnormal contraction of the esophageal body (59%; -value, 0.32), 4) dilation of the esophageal lumen (58%; -value, 0.53), 5) liquid remnant (57%; -value, 0.51), 6) Wrapping around EGJ (49%; -value, 0.14), and 7) food remnant (30%; -value, 0.88). Even in 22 patients with poor (grade 1) intraluminal expansion, corona appearance had highest sensitivity (88%) compared to other endoscopic findings (-value, 0.63). Conclusions: Among endoscopic findings using a ST Hood short-type to diagnose esophageal achalasia, corona appearance had the highest sensitivity and its consistency (-value) among endoscopists was substantial compared to other endoscopic findings. Similar results were obtained for esophageal achalasia cases with poor expansion. Endoscopic diagnosis of esophageal achalasia with hood attached is useful.
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Poly-lactic electrospun porous fibers have been widely used in tissue engineering scaffolds. However, the application of linear Poly-lactic is limited due to its poor hydrophilicity, which leads to phase separation and has been seldom used in porous fiber preparation. Instead, using of branching Poly-lactic acts as a new effective method to prepare porous fibers because it can increase Poly-lactic polar property and make it easy to be formulated in the following application. In current study, we prepared an ultra-high molecular weight of high branching Poly-lactic with glycerol as the initiator by controlling the ring-opening polymerization time, adding amount of catalyst and glycerol. The structure, molecular weight and thermal properties of copolymers were tested subsequently. The result showed that the surface of the high branching Poly-lactic films is smooth, hydrophilic and porous. This branching Poly-lactic formed electrospun porous fibers, possessed a strong adsorption of silver ion. Comparing with the application of linear Poly-lactic and 3-arm Poly-lactic materials, our study provided a simple and efficient way to synthesize branching Poly-lactic polymer and prepare electrospun porous fibers, which may provide potential applications in the field of biomaterials for tissue engineering or antibacterial dressing.
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Poly-lactic electrospun porous fibers have been widely used in tissue engineering scaffolds. However, the application of linear Poly-lactic is limited due to its poor hydrophilicity, which leads to phase separation and has been seldom used in porous fiber preparation. Instead, using of branching Poly-lactic acts as a new effective method to prepare porous fibers because it can increase Poly-lactic polar property and make it easy to be formulated in the following application. In current study, we prepared an ultra-high molecular weight of high branching Poly-lactic with glycerol as the initiator by controlling the ring-opening polymerization time, adding amount of catalyst and glycerol. The structure, molecular weight and thermal properties of copolymers were tested subsequently. The result showed that the surface of the high branching Poly-lactic films is smooth, hydrophilic and porous. This branching Poly-lactic formed electrospun porous fibers, possessed a strong adsorption of silver ion. Comparing with the application of linear Poly-lactic and 3-arm Poly-lactic materials, our study provided a simple and efficient way to synthesize branching Poly-lactic polymer and prepare electrospun porous fibers, which may provide potential applications in the field of biomaterials for tissue engineering or antibacterial dressing.
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Predator dietary studies often assume that diet is reflective of the diversity and relative abundance of their prey. This interpretation ignores species-specific behavioural adaptations in prey that could influence prey capture. Here, we develop and describe a scalable biologging protocol, using animal-borne camera loggers, to elucidate the factors influencing prey capture by a seabird, the gentoo penguin (Pygoscelis papua). From the video evidence, we show, for the first time, that aggressive behavioural defence mechanisms by prey can deter prey capture by a seabird. Furthermore, we provide evidence demonstrating that these birds, which were observed hunting solitarily, target prey when they are most discernible. Specifically, birds targeted prey primarily while ascending and when prey were not tightly clustered. In conclusion, we show that prey behaviour can significantly influence trophic coupling in marine systems because despite prey being present, it is not always targeted. Thus, these predator-prey relationships should be accounted for in studies using marine top predators as samplers of mid to lower trophic level species.
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The costs of predation may exert significant pressure on the mode of communication used by an animal, and many species balance the benefits of communication (e.g. mate attraction) against the potential risk of predation. Four groups of toothed whales have independently evolved narrowband high-frequency (NBHF) echolocation signals. These signals help NBHF species avoid predation through acoustic crypsis by echolocating and communicating at frequencies inaudible to predators such as mammal-eating killer whales. Heaviside’s dolphins (Cephalorhynchus heavisidii) are thought to exclusively produce NBHF echolocation clicks with a centroid frequency around 125 kHz and little to no energy below 100 kHz. To test this, we recorded wild Heaviside’s dolphins in a sheltered bay in Namibia. We demonstrate that Heaviside’s dolphins produce a second type of click with lower frequency and broader bandwidth in a frequency range that is audible to killer whales. These clicks are used in burst-pulses and occasional click series but not foraging buzzes. We evaluate three different hypotheses and conclude that the most likely benefit of these clicks is to decrease transmission directivity and increase conspecific communication range. The expected increase in active space depends on background noise but ranges from 2.5 (Wenz Sea State 6) to 5 times (Wenz Sea State 1) the active space of NBHF signals. This dual click strategy therefore allows these social dolphins to maintain acoustic crypsis during navigation and foraging, and to selectively relax their crypsis to facilitate communication with conspecifics.
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Objective. To explore cross-sectional and longitudinal gray matter (GM) volume changes in migraine patients and their association with patients’ clinical characteristics and disease activity. Methods. Brain T2-weighted and 3D T1-weighted scans were acquired from 73 episodic migraineurs and 46 age- and sex-matched non-migraine controls at baseline. Twenty-four migraineurs and 25 controls agreed to be re-examined after a mean follow-up of 4 years. Using a general linear model and SPM12, a whole-brain analysis was performed to assess GM volume modifications. Results. At baseline, compared to controls, migraine patients showed lower cerebellar GM volume and higher volume of regions of the fronto-temporal lobes. At follow-up, migraineurs were significantly older than controls. Over the follow-up, migraineurs developed an increased volume of fronto-temporo-parietal regions, which was more prominent in patients with a higher baseline disease activity: long disease duration and high attack frequency. Migraineurs also developed decreased GM volume of visual areas, which was related to higher pain severity. Patients with an increased attack frequency at follow-up experienced both increased and decreased volume of nociceptive regions. In migraineurs, reduced GM volume of extrastriate visual areas during the follow-up was significantly correlated to baseline disease activity: shorter disease duration and lower attack frequency. Conclusion. In this cohort, the migraine brain changes dynamically over time and different pathophysiological mechanisms can occur in response to patients’ disease severity. The interaction between predisposing brain traits and experience-dependent responses might vary across different nociceptive and visual areas, thus leading to distinct patterns of longitudinal GM volume changes.
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