bluuebunny/crossref_metadata_2025_split huggingface dataset:
Drought resistance across California ecosystems: evaluating changes in carbon dynamics using satellite imagery
Authors: Malone Sparkle L. , Tulbure Mirela G. , Pérez‐Luque Antonio J. , Assal Timothy J. , Bremer Leah L. , Drucker Debora P. , Hillis Vicken , Varela Sara , Goulden Michael L. 
Published: November 2016

AbstractDrought is a global issue that is exacerbated by climate change and increasing anthropogenic water demands. The recent occurrence of drought in California provides an important opportunity to examine drought response across ecosystem classes (forests, shrublands, grasslands, and wetlands), which is essential to understand how climate influences ecosystem structure and function. We quantified ecosystem resistance to drought by comparing changes in satellite‐derived estimates of water‐use efficiency (WUE = net primary productivity [NPP]/evapotranspiration [ET]) under normal (i.e., baseline) and drought conditions (ΔWUE = WUE2014 − baseline WUE). With this method, areas with increasing WUE under drought conditions are considered more resilient than systems with declining WUE. Baseline WUE varied across California (0.08 to 3.85 g C/mm H2O) and WUE generally increased under severe drought conditions in 2014. Strong correlations between ΔWUE, precipitation, and leaf area index (LAI) indicate that ecosystems with a lower average LAI (i.e., grasslands) also had greater C‐uptake rates when water was limiting and higher rates of carbon‐uptake efficiency (CUE = NPP/LAI) under drought conditions. We also found that systems with a baseline WUE ≤ 0.4 exhibited a decline in WUE under drought conditions, suggesting that a baseline WUE ≤ 0.4 might be indicative of low drought resistance. Drought severity, precipitation, and WUE were identified as important drivers of shifts in ecosystem classes over the study period. These findings have important implications for understanding climate change effects on primary productivity and C sequestration across ecosystems and how this may influence ecosystem resistance in the future.
Electrochemical Characterization of the Microfabricated Electrochemical Sensor‐Array System
Authors: Pitman Kätlin , Raud Merlin , Scotti Gianmario , Jokinen Ville P. , Franssila Sami , Nerut Jaak , Lust Enn , Kikas Timo 
Published: November 2016

AbstractMicrofabrication technology has been used to prepare a microchip sensor‐array with six sets of platinum electrodes. Chromium/platinum (10 nm/100 nm thick) were sputtered on a borosilicate wafer and patterned by wet etching method. The electrodes were designed with working electrode area of 700×400 μm in the middle and a 200 μm wide and 2600 μm long counter electrode surrounding it from three sides in a U‐shape. The connection pads (1000×1500 μm) were located at the edge of a sensor‐array chip. Silicon wafer was etched through to form holes with slanting side walls for immobilization cavities. The silicon and the borosilicate wafers were adhesion bonded with SU‐8 epoxy resin. The cyclic voltammetry and electrochemical impedance experiments were carried out in a three‐electrode electrochemical system to characterize the fabricated sensor‐array chip. The results show that the current density depends on the electrode potential sweep rate ν. Also, current density depends on the concentration of potassium hexacyanoferrate(III). At slow potential sweep rates (ν≤0.01 V s−1) the steady‐state signal is achieved and the electrodes behave as micro‐electrodes. Such an array is a promising candidate for fast and simple biochemical oxygen demand (BOD) measurements.
A moving particle semi‐implicit method for free surface flow: Improvement in inter‐particle force stabilization and consistency restoring
Authors: Xiang Hao , Chen Bin 
Published: November 2016

AbstractThe moving particle semi‐implicit (MPS) method has been widely applied in free surface flows. However, the implementation of MPS remains limited because of compressive instability occurred when the particles are under compressive stress states. This study proposed an inter‐particle force stabilization and consistency restoring MPS (IFS‐CR‐MPS) method to overcome this numerical instability. For inter‐particle force stabilization, a hyperbolic‐shaped quintic kernel function is developed with a non‐negative and smooth second order derivative to satisfy the stability criterion under compressive stress state. Then, a contrastive study is conducted on the contradiction between the common understanding of the conventional MPS hyperbolic‐shaped kernel function and its performance. The result shows that the conventional MPS hyperbolic‐shaped kernel function can easily cause violent repulsive inter‐particle force and then lead to the compressive instability. Therefore, the first order derivative of the modified hyperbolic‐shaped quintic kernel function is recommended as the form of the contribution of the neighbor particles to achieve a more stable inter‐particle repulsive force. For consistency restoring, the Taylor series expansion and the hyperbolic‐shaped quintic kernel are combined to improve the accuracy of the viscosity and pressure calculation. The IFS‐CR‐MPS algorithm is subsequently verified by the inviscid hydrostatic pressure, jet impacting, and viscous droplet impacting problems. These results can be used for choosing kernel function and the contribution of neighbor particles in particle methods. Copyright © 2016 John Wiley & Sons, Ltd.
Neural signatures of trust in reciprocity: A coordinate‐based meta‐analysis
Authors: Bellucci Gabriele , Chernyak Sergey V. , Goodyear Kimberly , Eickhoff Simon B. , Krueger Frank 
Published: November 2016

AbstractTrust in reciprocity (TR) is defined as the risky decision to invest valued resources in another party with the hope of mutual benefit. Several fMRI studies have investigated the neural correlates of TR in one‐shot and multiround versions of the investment game (IG). However, an overall characterization of the underlying neural networks remains elusive. Here, a coordinate‐based meta‐analysis was employed (activation likelihood estimation method, 30 articles) to investigate consistent brain activations in each of the IG stages (i.e., the trust, reciprocity and feedback stage). Results showed consistent activations in the anterior insula (AI) during trust decisions in the one‐shot IG and decisions to reciprocate in the multiround IG, likely related to representations of aversive feelings. Moreover, decisions to reciprocate also consistently engaged the intraparietal sulcus, probably involved in evaluations of the reciprocity options. On the contrary, trust decisions in the multiround IG consistently activated the ventral striatum, likely associated with reward prediction error signals. Finally, the dorsal striatum was found consistently recruited during the feedback stage of the multiround IG, likely related to reinforcement learning. In conclusion, our results indicate different neural networks underlying trust, reciprocity, and feedback learning. These findings suggest that although decisions to trust and reciprocate may elicit aversive feelings likely evoked by the uncertainty about the decision outcomes and the pressing requirements of social standards, multiple interactions allow people to build interpersonal trust for cooperation via a learning mechanism by which they arguably learn to distinguish trustworthy from untrustworthy partners. Hum Brain Mapp 38:1233–1248, 2017. © 2016 Wiley Periodicals, Inc.
Cognitive phenotypes in parkinson's disease differ in terms of brain‐network organization and connectivity
Authors: Lopes Renaud , Delmaire Christine , Defebvre Luc , Moonen Anja J. , Duits Annelien A. , Hofman Paul , Leentjens Albert F.G. , Dujardin Kathy 
Published: November 2016

AbstractCognitive deficits are common in Parkinson's disease and we suspect that dysfunctions of connected brain regions can be the source of these deficits. The aim of the present study was to investigate changes in whole‐brain intrinsic functional connectivity according to differences in cognitive profiles in Parkinson's disease. 119 participants were enrolled and divided into four groups according to their cognitive phenotypes (determined by a cluster analysis): (i) 31 cognitively intact patients (G1), (ii) 31 patients with only slight mental slowing (G2), (iii) 43 patients with mild to moderate deficits mainly in executive functions (G3), (iv) 14 patients with severe deficits in all cognitive domains (G4–5). Rs‐fMRI whole‐brain connectivity was examined by two complementary approaches: graph theory for studying network functional organization and network‐based statistics (NBS) for exploring functional connectivity amongst brain regions. After adjustment for age, duration of formal education and center of acquisition, there were significant group differences for all functional organization indexes: functional organization decreased (G1 > G2 > G3 > G4‐5) as cognitive impairment worsened. Between‐group differences in functional connectivity (NBS corrected, P < 0.01) mainly concerned the ventral prefrontal, parietal, temporal and occipital cortices as well as the basal ganglia. In Parkinson's disease, brain network organization is progressively disrupted as cognitive impairment worsens, with an increasing number of altered connections between brain regions. We observed reduced connectivity in highly associative areas, even in patients with only slight mental slowing. The association of slowed mental processing with loss of connectivity between highly associative areas could be an early marker of cognitive impairment in Parkinson's disease and may contribute to the detection of prodromal forms of Parkinson's disease dementia. Hum Brain Mapp 38:1604–1621, 2017. © 2016 Wiley Periodicals, Inc.
Acute systemic MK‐801 induced functional uncoupling between hippocampal areas CA3 and CA1 with distant effect in the retrosplenial cortex
Authors: Buchtová Helena , Fajnerová Iveta , Stuchlík Aleš , Kubík Štěpán 
Published: November 2016

ABSTRACTThe hippocampus and retrosplenial cortex are integrated within a higher‐order cognitive circuit supporting relational (spatial, contextual, episodic) forms of learning and memory. Hippocampal place cells can coordinate multiple parallel representations in the same physical environment. Novel environment exploration triggers expression of immediate‐early genes (IEGs) Arc and Homer1a in spatial context‐specific ensembles of CA1 and CA3 neurons. Less is know about ensemble coding in the retrosplenial cortex (RSC), a region directly connected and functionally coupled to CA1. Hippocampal and retrosplenial damage is found in patients with schizophrenia alongside cognitive deficits affecting relational memory. Systemic administration of non‐competitive NMDAR antagonists such as MK‐801 is used to model psychosis in animals and humans. Acute systemic MK‐801 (0.15 mg/kg) impaired cognitive control in rats and ensemble code for spatial context in CA1. Here, we use expression of immediate‐early genes Arc and Homer 1a to examine ensemble coding in rat CA3 and RSC to test if the effect of MK‐801 extends upstream and downstream of CA1, respectively. Different rats explored the same context twice (A/A), explored two distinct contexts (A/B) or remained in their home cage (CC). In contrast to CA1, MK‐801 did not affect ensemble coding in CA3. Unlike CA3 and CA1, similarity of RSC ensembles active during exploration did not reflect change in spatial context, but MK‐801 (0.15 mg/kg) increased similarity in RSC ensembles active during spontaneous behavior in the home cage. The data provide support for MK‐801‐induced functional uncoupling between CA3 and CA1 and suggest that ensemble coding deficit may extend downstream of CA1. This deficit may reflect hyperassociative state in the cognitive circuit underlying cognitive disorganization in psychosis. © 2016 Wiley Periodicals, Inc.
Repetition reveals ups and downs of hippocampal, thalamic, and neocortical engagement during mnemonic decisions
Authors: Reagh Zachariah M. , Murray Elizabeth A. , Yassa Michael A. 
Published: November 2016

ABSTRACTThe extent to which current information is consistent with past experiences and our capacity to recognize or discriminate accordingly are key factors in flexible memory‐guided behavior. Despite a wealth of evidence linking hippocampal and neocortical computations to these phenomena, many important factors remain poorly understood. One such factor is repeated encoding of learned information. In this experiment, participants completed a task in which study stimuli were incidentally encoded either once or three separate times during high‐resolution fMRI scanning. We asked how repetition influenced recognition and discrimination memory judgments, and how this affects engagement of hippocampal and neocortical regions. Repetition revealed shifts in engagement in an anterior (ventral) CA1‐thalamic‐medial prefrontal network related to true and false recognition. Conversely, repetition revealed shifts in a posterior (dorsal) dentate/CA3‐parahippocampal‐restrosplenial network related to accurate discrimination. These differences in engagement were accompanied by task‐related correlations in respective anterior and posterior networks. In particular, the anterior thalamic region observed during recognition judgments is functionally and anatomically consistent with nucleus reuniens in humans, and was found to mediate correlations between the anterior CA1 and medial prefrontal cortex. These findings offer new insights into how repeated experience affects memory and its neural substrates in hippocampal‐neocortical networks. © 2016 Wiley Periodicals, Inc.
Visual short‐term memory for high resolution associations is impaired in patients with medial temporal lobe damage
Authors: Koen Joshua D. , Borders Alyssa A. , Petzold Michael T. , Yonelinas Andrew P. 
Published: November 2016

ABSTRACTThe medial temporal lobe (MTL) plays a critical role in episodic long‐term memory, but whether the MTL is necessary for visual short‐term memory is controversial. Some studies have indicated that MTL damage disrupts visual short‐term memory performance whereas other studies have failed to find such evidence. To account for these mixed results, it has been proposed that the hippocampus is critical in supporting short‐term memory for high resolution complex bindings, while the cortex is sufficient to support simple, low resolution bindings. This hypothesis was tested in the current study by assessing visual short‐term memory in patients with damage to the MTL and controls for high resolution and low resolution object‐location and object‐color associations. In the location tests, participants encoded sets of two or four objects in different locations on the screen. After each set, participants performed a two‐alternative forced‐choice task in which they were required to discriminate the object in the target location from the object in a high or low resolution lure location (i.e., the object locations were very close or far away from the target location, respectively). Similarly, in the color tests, participants were presented with sets of two or four objects in a different color and, after each set, were required to discriminate the object in the target color from the object in a high or low resolution lure color (i.e., the lure color was very similar or very different, respectively, to the studied color). The patients were significantly impaired in visual short‐term memory, but importantly, they were more impaired for high resolution object‐location and object‐color bindings. The results are consistent with the proposal that the hippocampus plays a critical role in forming and maintaining complex, high resolution bindings. © 2016 Wiley Periodicals, Inc.
Material Specificity Drives Medial Temporal Lobe Familiarity But Not Hippocampal Recollection
Authors: Kafkas Alex , Migo Ellen M. , Morris Robin G. , Kopelman Michael D. , Montaldi Daniela , Mayes Andrew R. 
Published: November 2016

ABSTRACTThe specific role of the perirhinal (PRC), entorhinal (ERC) and parahippocampal cortices (PHC) in supporting familiarity‐based recognition remains unknown. An fMRI study explored whether these medial temporal lobe (MTL) structures responded in the same way or differentially to familiarity as a function of stimulus type at recognition. A secondary aim was to explore whether the hippocampus responds in the same way to equally strong familiarity and recollection and whether this is influenced by the kind of stimulus involved. Univariate and multivariate analyses revealed that familiarity responses in the PRC, ERC, PHC and the amygdala are material‐specific. Specifically, the PRC and ERC selectively responded to object familiarity, while the PHC responded to both object and scene familiarity. The amygdala only responded to familiarity memory for faces. The hippocampus did not respond to stimulus familiarity for any of the three types of stimuli, but it did respond to recollection for all three types of stimuli. This was true even when recollection was contrasted to equally accurate familiarity. Overall, the findings suggest that the role of the MTL neocortices and the amygdala in familiarity‐based recognition depends on the kind of stimulus in memory, whereas the role of the hippocampus in recollection is independent of the type of cuing stimulus. © 2016 The Authors Hippocampus Published by Wiley Periodicals, Inc.
Spectral diffuse reflectance and autofluorescence imaging can perform early prediction of blood vessel occlusion in skin flaps
Authors: Chen Shuo , Zhu Caigang , Hoe‐Kong Chui Christopher , Sheoran Gyanendra , Tan Bien‐Keem , Liu Quan 
Published: November 2016

Flap transfer has become a common technique in reconstructive surgery. However, a significant number of compromised skin flaps are not successfully salvaged because the current clinical method for flap assessment relies heavily on the clinician's experience. Vascular occlusion is the major reason for flap failure, thus the accurate and objective early prediction of blood vessel occlusion is vitally important. Our parallel point measurement study has demonstrated the great potential of joint diffuse reflectance and autofluorescence spectroscopy in the early detection and differentiation of venous and arterial occlusion in skin flaps. Unfortunately, the technique of point measurements is not suitable to examine a large skin flap when a high spatial resolution is required. In this study, we attempted to overcome this problem by performing spectral diffuse reflectance and autofluorescence imaging on a rat skin flap model. Both imaging data and reconstructed spectra were used to statistically differentiate control flaps, arterially occluded flaps and venously occluded flaps. Our preliminary results suggest that the technique of joint diffuse reflectance and autofluorescence spectroscopic imaging can achieve high classification accuracy thus could be used to detect and differentiate flaps with venous and arterial occlusion accurately at an early time point in a large skin flap.
Typical reconstructed spectra of (a) diffuse reflectance and (b) autofluorescence after normalization.magnified imageTypical reconstructed spectra of (a) diffuse reflectance and (b) autofluorescence after normalization.
Prevalence and incidence of sarcopenia in the very old: findings from the Newcastle 85+ Study
Authors: Dodds Richard Matthew , Granic Antoneta , Davies Karen , Kirkwood Thomas B. L. , Jagger Carol , Sayer Avan Aihie 
Published: November 2016

AbstractIntroductionRecognition that an older person has sarcopenia is important because this condition is linked to a range of adverse outcomes. Sarcopenia becomes increasingly common with age, and yet there are few data concerning its descriptive epidemiology in the very old (aged 85 years and above). Our aims were to describe risk factors for sarcopenia and estimate its prevalence and incidence in a British sample of the very old.MethodsWe used data from two waves (2006/07 and 2009/10) of the Newcastle 85+ Study, a cohort born in 1921 and registered with a Newcastle/North Tyneside general practice. We assessed sarcopenia status using the European Working Group on Sarcopenia in Older People (EWGSOP) definition. Grip strength was measured using a Takei digital dynamometer (Takei Scientific Instruments Ltd., Niigata, Japan), gait speed was calculated from the Timed Up and Go test, and lean mass was estimated using a Tanita‐305 body fat analyzer. We used logistic regression to examine associations between risk factors for prevalent sarcopenia at baseline and incident sarcopenia at follow‐up.ResultsEuropean Working Group on Sarcopenia in Older People sarcopenia was present in 21% of participants at baseline [149/719 participants, mean age 85.5 (0.4) years]. Many participants had either slow gait speed or weak grip strength (74.3%), and hence measurement of muscle mass was frequently indicated by the EWGSOP definition. Incidence data were available for 302 participants, and the incident rate was 3.7 cases per 100 person years at risk. Low Standardized Mini‐Mental State Examination, lower occupational social class, and shorter duration of education were associated with sarcopenia at baseline, while low muscle mass was associated with incident sarcopenia. Low body mass index (BMI) was a risk factor for both in a graded fashion, with each unit decrease associated with increased odds of prevalent [odds ratio (OR) 1.29, 95% confidence interval (CI): 1.21, 1.37] and incident (OR 1.20, 95% CI: 1.08, 1.33) sarcopenia.ConclusionsTo our knowledge, this is the first study to describe prevalence and incidence of EWGSOP sarcopenia in the very old. Low BMI was a risk factor for both current and future sarcopenia; indeed, there was some evidence that low BMI may be a reasonable proxy for low lean mass. Overall, the high prevalence of sarcopenia among the very old suggests that this group should be a focus for future research.
Towards understanding the distribution and tumor targeting of sericin regulated spherical calcium phosphate nanoparticles
Authors: Zhao Ruibo , Ren Xiaoyuan , Xie Chungang , Kong Xiangdong 
Published: November 2016

AbstractThe study of calcium phosphate (CaP) nanoparticles in vivo is still incomplete, which has limited their applications for biomedical delivery. Herein, we synthesized amorphous spherical calcium phosphate (S‐CaP) nanoparticles with an average size of 80 nm via a co‐precipitation method in the presence of silk sericin as the regulation template. S‐CaP was labeled by the near‐infrared dye reagent DiR, and then, the labeled nanoparticles (S‐CaP@DiR) were used to investigate the distribution and degradation in healthy mice by IVIS and TEM. The results showed that the S‐CaP nanoparticles were mainly distributed in the liver, and ∼90% of them (500 μg) could be degraded by the liver within 2 weeks. Tumor‐bearing mice were then prepared, and the S‐CaP was injected intravenously. Strikingly, the nanoparticles can effectively target solid tumors in cancer cell‐bearing mice, indicating that the solid tumor was a foundation for the enrichment of the nanoparticles by the EPR effect, which showed the important potential of biodegradable inorganic nanoparticles in clinical drugs for tumor therapy.