bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sleep patterns, daytime predation, and the evolution of diurnal sleep site selection in lorisiforms
Authors: Svensson Magdalena S. , Nekaris K.A.I. , Bearder Simon K. , Bettridge Caroline M. , Butynski Thomas M. , Cheyne Susan M. , Das Nabajit , de Jong Yvonne A. , Luhrs Averee M. , Luncz Lydia V. , Maddock Simon T. , Perkin Andrew , Pimley Elizabeth , Poindexter Stephanie A. , Reinhardt Kathleen D. , Spaan Denise , Stark Danica J. , Starr Carly R. , Nijman Vincent 
Published: July 2018

AbstractObjectivesSynthesize information on sleep patterns, sleep site use, and daytime predation at sleep sites in lorisiforms of Asia and Africa (10 genera, 36 species), and infer patterns of evolution of sleep site selection.Materials and methodsWe conducted fieldwork in 12 African and six Asian countries, collecting data on sleep sites, timing of sleep and predation during daytime. We obtained additional information from literature and through correspondence. Using a phylogenetic approach, we established ancestral states of sleep site selection in lorisiforms and traced their evolution.ResultsThe ancestral lorisiform was a fur‐clinger and used dense tangles and branches/forks as sleep sites. Use of tree holes and nests as sleep sites emerged ∼22 Mya (range 17–26 Mya) in Africa, and use of bamboo emerged ∼11 (7–14) Mya in Asia and later in Africa. Fur clinging and some sleep sites (e.g., tree holes, nests, but not bamboo or dense tangles) show strong phylogenetic signal. Nests are used by Galagoides, Paragalago, Galago and Otolemur; tree holes by Galago, Paragalago, Sciurocheirus and Perodicticus; tangles by Nycticebus, Loris, Galagoides, Galago, Euoticus, Otolemur, Perodicticus and Arctocebus; all but Sciurocheirus and Otolemur additionally sleep on branches/forks. Daytime predation may affect sleep site selection and sleep patterns in some species of Nycticebus, Galago, Galagoides, Otolemur and Perodicticus. Most lorisiforms enter their sleep sites around sunrise and leave around sunset; several are active during twilight or, briefly, during daytime.ConclusionVariations in sleep behavior, sleep patterns and vulnerability to daytime predation provide a window into the variation that was present in sleep in early primates. Overall, lorisiforms use the daytime for sleeping and no species can be classified as cathemeral or polycyclic.
Sleep variability and nighttime activity among Tsimane forager‐horticulturalists
Authors: Yetish Gandhi , Kaplan Hillard , Gurven Michael 
Published: July 2018

AbstractObjectivesA common presumption in sleep research is that “normal” human sleep should show high night‐to‐night consistency. Yet, intra‐individual sleep variation in small‐scale subsistence societies has never been studied to test this idea. In this study, we assessed the degree of nightly variation in sleep patterns among Tsimane forager‐horticulturalists in Bolivia, and explored possible drivers of the intra‐individual variability.MethodsWe actigraphically recorded sleep among 120 Tsimane adults (67 female), aged 18–91, for an average of 4.9 nights per person using the Actigraph GT3X and Philips Respironics Actiwatch 2. We assessed intra‐individual variation using intra‐class correlations and average deviation from each individual's average sleep duration, onset, and offset times ().ResultsOnly 31% of total variation in sleep duration was due to differences among different individuals, with the remaining 69% due to nightly differences within the same individuals. We found no statistically significant differences in Tsimane sleep duration by day‐of‐the‐week. Nightly variation in sleep duration was driven by highly variable sleep onset, especially for men. Nighttime activities associated with later sleep onset included hunting, fishing, housework, and watching TV.ConclusionsIn contrast to nightly sleep variation in the United States being driven primarily by “sleeping‐in” on weekends, Tsimane sleep variation, while comparable to that observed in the United States, was driven by changing “bedtimes,” independent of day‐of‐the‐week. We propose that this variation may reflect adaptive responses to changing opportunity costs to sleep/nighttime activity.
The cost of deep sleep: Environmental influences on sleep regulation are greater for diurnal lemurs
Authors: Samson David R. , Bray Joel , Nunn Charles L. 
Published: July 2018

AbstractObjectivesPrimates spend almost half their lives asleep, yet we know little about how evolution has shaped variation in the duration or intensity of sleep (i.e., sleep regulation) across primate species. Our objective was to test hypotheses related to how sleeping site security influences sleep intensity in different lemur species.MethodsWe used actigraphy and infrared videography to generate sleep measures in 100 individuals (males = 51, females = 49) of seven lemur species (genera: Eulemur, Lemur, Propithecus, and Varecia) at the Duke Lemur Center in Durham, NC. We also generated experimental data using sleep deprivation for 16 individuals. This experiment used a pair‐wise design for two sets of paired lemurs from each genus, where the experimental pair experienced a sleep deprivation protocol while the control experienced normal sleeping conditions. We calculated a sleep depth composite metric from weighted z scores of three sleep intensity variables.ResultsWe found that, relative to cathemeral lemurs, diurnal Propithecus was characterized by the deepest sleep and exhibited the most disruptions to normal sleep‐wake regulation when sleep deprived. In contrast, Eulemur mongoz was characterized by significantly lighter sleep than Propithecus, and E. mongoz showed the fewest disruptions to normal sleep‐wake regulation when sleep deprived. Security of the sleeping site led to greater sleep depth, with access to outdoor housing linked to lighter sleep in all lemurs that were studied.ConclusionsWe propose that sleeping site security was an essential component of sleep regulation throughout primate evolution. This work suggests that sleeping site security may have been an important factor associated with the evolution of sleep in early and later hominins.
Savanna chimpanzees adjust sleeping nest architecture in response to local weather conditions
Authors: Stewart Fiona A. , Piel Alexander K. , Azkarate Jurgi C. , Pruetz Jill D. 
Published: July 2018

AbstractObjectivesGreat ape nests are hypothesized to aid safe, secure sleep via providing thermoregulation or protection from predators and vectors. We aimed to describe and investigate variation in chimpanzee nest architecture across two populations in response to local weather conditions.Materials and MethodsWe experimentally tested whether nests provide insulation by measuring heat loss within and outside nests, and took detailed measurements of the number, size, and type of materials used in nest building across two dry‐habitat research sites (Fongoli, Senegal, and Issa, Tanzania). We tested application of principal components analysis (PCA) to extract composite quantitative measures of the key components of shape and architecture, before testing how PCs vary across populations with overnight weather conditions that reflect hypothesized thermoregulatory function.ResultsHeat loss is greater and occurs faster outside of nests. PCA allowed meaningful comparison of nests within and between sites. Nest variation at both sites revealed chimpanzees built thicker nests in cooler conditions and used more broken branches and support in moister conditions. Chimpanzees in Fongoli used more lining and mattress material in colder conditions, whilst in Issa nest depth and support branch size were larger in windier conditions.DiscussionShape and architectural measures reflected insulation and stability of nest structure. Chimpanzees in Fongoli and Issa may achieve the same functional goals by adjusting nest shape and architecture in different ways. These results suggest that wild chimpanzees show flexible building techniques in response to local, overnight weather conditions in making an insulating and stable, supportive platform for sleep.
Nocturnal activity in wild chimpanzees (Pan troglodytes): Evidence for flexible sleeping patterns and insights into human evolution
Authors: Tagg Nikki , McCarthy Maureen , Dieguez Paula , Bocksberger Gaëlle , Willie Jacob , Mundry Roger , Stewart Fiona , Arandjelovic Mimi , Widness Jane , Landsmann Anja , Agbor Anthony , Angedakin Samuel , Ayimisin Ayuk Emmanuel , Bessone Mattia , Brazzola Gregory , Corogenes Katherine , Deschner Tobias , Dilambaka Emmanuel , Eno‐Nku Manasseh , Eshuis Henk , Goedmakers Annemarie , Granjon Anne‐Céline , Head Josephine , Hermans Veerle , Jones Sorrel , Kadam Parag , Kambi Mohamed , Langergraber Kevin E. , Lapeyre Vincent , Lapuente Juan , Lee Kevin , Leinert Vera , Maretti Giovanna , Marrocoli Sergio , Meier Amelia , Nicholl Sonia , Normand Emmanuelle , Ormsby Lucy Jayne , Piel Alex , Robinson Orume , Sommer Volker , ter Heegde Martijn , Tickle Alexander , Ton Els , van Schijndel Joost , Vanleeuwe Hilde , Vergnes Virginie , Wessling Erin , Wittig Roman M. , Zuberbuehler Klaus , Kuehl Hjalmar , Boesch Christophe 
Published: July 2018

AbstractObjectivesWe investigated occurrences and patterns of terrestrial nocturnal activity in wild chimpanzees (Pan troglodytes) and modelled the influence of various ecological predictors on nocturnal activity.MethodsData were extracted from terrestrial camera‐trap footage and ecological surveys from 22 chimpanzee study sites participating in the Pan African Programme: The Cultured Chimpanzee. We described videos demonstrating nocturnal activity, and we tested the effects of the percentage of forest, abundance of predators (lions, leopards and hyenas), abundance of large mammals (buffalos and elephants), average daily temperature, rainfall, human activity, and percent illumination on the probability of nocturnal activity.ResultsWe found terrestrial nocturnal activity to occur at 18 of the 22 study sites, at an overall average proportion of 1.80% of total chimpanzee activity, and to occur during all hours of the night, but more frequently during twilight hours. We found a higher probability of nocturnal activity with lower levels of human activity, higher average daily temperature, and at sites with a larger percentage of forest. We found no effect of the abundance of predators and large mammals, rainfall, or moon illumination.DiscussionChimpanzee terrestrial nocturnal activity appears widespread yet infrequent, which suggests a consolidated sleeping pattern. Nocturnal activity may be driven by the stress of high daily temperatures and may be enabled at low levels of human activity. Human activity may exert a relatively greater influence on chimpanzee nocturnal behavior than predator presence. We suggest that chimpanzee nocturnal activity is flexible, enabling them to respond to changing environmental factors.
Lord of The Crowns: A New Precious in the Kingdom of Clustomesogens
Authors: Guy Kevin , Ehni Philipp , Paofai Serge , Forschner Robert , Roiland Claire , Amela‐Cortes Maria , Cordier Stéphane , Laschat Sabine , Molard Yann 
Published: July 2018

AbstractReplacing pure inorganic materials by functional organic–inorganic hybrid ones to lower production costs has become a major challenge, in particular for the optoelectronic industry. Adding nanostructuration abilities meanwhile preserving homogeneity is even more challenging for this class of new materials. Here we show that red‐NIR emissive ternary molybdenum cluster salts can be assembled to liquid crystalline 15C5 crown ethers. The resulting hybrids are homogeneous and stable up to high temperature despite the weakness of the supramolecular interactions binding both components. These are illustrated by 133Cs MAS NMR. All hybrids show hexagonal columnar arrangements and strong red‐NIR emission. Surprisingly, when chlorinated clusters are used instead of brominated ones, the mesophase stability is largely enhanced.
Gold(I)‐Catalyzed Tandem Cycloisomerization of 1,5‐Enyne Ethers by Hydride Transfer
Authors: Lu Xiao‐Lin , Lyu Mao‐Yun , Peng Xiao‐Shui , Wong Henry N. C. 
Published: July 2018

AbstractA novel gold‐catalyzed tandem protocol, initiated by hydride transfer in the presence of catalytic (C6F5)3PAuCl/AgSbF6, for the formation of fused polycyclic ring systems has been achieved. This tandem reaction provides rapid access to various fused polycyclic species in a single chemical operation, leading to stereospecific formation of two carbon–carbon bonds and three rings.
Electrostatic‐Driven Dynamic Jamming of 2D Nanoparticles at Interfaces for Controlled Molecular Diffusion
Authors: Luo Jianhui , Zeng Minxiang , Peng Baoliang , Tang Yijie , Zhang Lecheng , Wang Pingmei , He Lipeng , Huang Dali , Wang Ling , Wang Xuezhen , Chen Mingfeng , Lei Shijun , Lin Pengcheng , Chen Ying , Cheng Zhengdong 
Published: July 2018

AbstractDynamically engineering the interfacial interaction of nanoparticles has emerged as a new approach for bottom‐up fabrication of smart systems to tailor molecular diffusion and controlled release. Janus zwitterionic nanoplates are reported that can be switched between a locked and unlocked state at interfaces upon changing surface charge, allowing manipulation of interfacial properties in a fast, flexible, and switchable manner. Combining experimental and modeling studies, an unambiguous correlation is established among the electrostatic energy, the interface geometry, and the interfacial jamming states. As a proof‐of‐concept, the well‐controlled interfacial jamming of nanoplates enabled the switchable molecular diffusion through liquid–liquid interfaces, confirming the feasibility of using nanoparticle‐based surfactants for advanced controlled release.
Exploration into the Syntheses of Gallium‐ and Indiumborates under Extreme Conditions: M5B12O25(OH): Structure, Luminescence, and Surprising Photocatalytic Properties
Authors: Vitzthum Daniela , Wurst Klaus , Pann Johann M. , Brüggeller Peter , Seibald Markus , Huppertz Hubert 
Published: July 2018

AbstractExplorative solid‐state chemistry led to the discovery of the two new compounds Ga5B12O25(OH) and In5B12O25(OH). Extreme synthetic conditions within the range of 12 GPa and a temperature of 1450 °C realized in a Walker‐type multianvil apparatus resulted in the formation of an unprecedented tetragonal structure with the exclusive presence of condensed BO4 tetrahedra, forming cuboctahedral cavities. Doping of these cavities with Eu3+ in In5B12O25(OH) yielded in an orange–red luminescence. Photocatalytic tests of In5B12O25(OH) revealed a hydrogen production rate comparable to TiO2 but completely co‐catalyst free.
Limited progress in sustainable development: Factors influencing the environmental management and reporting of South African JSE‐listed companies
Authors: Kitsikopoulos Claudia , Schwaibold Ute , Taylor Douglas 
Published: July 2018

AbstractAlthough public, governmental, international and stakeholder pressure have led to corporations conforming to better sustainability performance, there has been an insignificant reduction in environmental degradation levels, and progress in sustainable development is limited. This study examines which factors influencing environmental management and reporting in South Africa could potentially contribute to this limited progress. The study was based on a series of interviews with sustainability managers of JSE‐listed firms. Results suggest that stock exchange listing requirements, internal processes and structures, experienced staff and the sustainability committee positively influence environmental and overall corporate sustainability, yet that resource and time constraints, as well as reporting fatigue, potentially limit the advancement of sustainable development. This restricts the further reduction of environmental degradation, which is urgently necessary in light of the harmful impacts that for example climate change has on the environment, societies and economies.
Iron overloaded polarizes macrophage to proinflammation phenotype through ROS/acetyl‐p53 pathway
Authors: Zhou Yun , Que Ke‐Ting , Zhang Zhen , Yi Zu J. , Zhao Ping X. , You Yu , Gong Jian‐Ping , Liu Zuo‐Jin 
Published: July 2018

AbstractPurposeMacrophages play critical roles in inflammation and wound healing and can be divided into two subtypes: classically activated (M1) and alternatively activated (M2) macrophages. Macrophages also play important roles in regulating iron homeostasis, and intracellular iron accumulation induces M1‐type macrophage polarization which provides a potential approach to tumor immunotherapy through M2 tumor‐associated macrophage repolarization. However, the mechanisms underlying iron‐induced M1 polarization remain unclear.MethodsWestern blotting, qRT‐PCR, and flow cytometry were used to detect the polarization indexes in RAW 264.7 murine macrophages treated with iron, and Western bloting and qRT‐PCR were used to detect p21 expression. The compound 2,7‐dichlorofluorescein diacetate was used to measure reactive oxygen species (ROS) levels in macrophages after iron or N‐acetyl‐l‐cysteine (NAC) treatment. The p300/CREB‐binding protein (CBP) inhibitor C646 was used to inhibit p53 acetylation, and Western bloting, qRT‐PCR, and immunofluorescence were used to detect p53 expression and acetylation. BALB/c mice were subcutaneously injected with H22 hepatoma cells, and macrophage polarization status was investigated after tail intravenous injection of iron. Immunohistochemical staining was used to evaluate the protein expression of cluster of differentiation 86 (CD86) and EGF‐like module‐containing mucin‐like hormone receptor‐like 1 (F4/80) in the subcutaneous tumors.ResultsIron overload induced M1 polarization by increasing ROS production and inducing p53 acetylation in RAW cells, and reduction in ROS levels by NAC repressed M1 polarization and p53 acetylation. Inhibition of acetyl‐p53 by a p300/CBP inhibitor prevented M1 polarization and inhibited p21 expression. These results showed that high ROS levels induced by iron overload polarized macrophages to the M1 subtype by enhancing p300/CBP acetyltransferase activity and promoting p53 acetylation.
Synergistic Production of Methyl Lactate from Carbohydrates Using an Ionic Liquid Functionalized Sn‐Containing Catalyst
Authors: Wang Fenfen , Wen Yi , Fang Yanxiong , Ji Hongbing 
Published: July 2018

AbstractConsiderable progress has been made recently in the catalytic conversion of renewable biomass resources to methyl lactate (MLA). However, conceiving eco‐friendly and effective catalytic systems for the production of MLA from biomass carbohydrates remains a key challenge. Herein, we report a multifunctional catalyst Sn(salen)/IL, consisting of a Sn(salen) complex and an imidazolium‐based ionic liquid (IL), which acts via an intramolecular synergistic effect to convert carbohydrates to MLA in methanol. The versatile properties of the resultant catalyst were revealed to be responsible for the conversion of fructose to MLA and the efficient suppression of undesired side reactions. This catalyst displayed outstanding catalytic activity, high selectivity, and excellent recyclability, giving an MLA yield of up to 68.9 % at 160 °C after 2 h. The results of this study will contribute to new approaches for designing synergistic catalysts for producing liquid fuels and chemicals from biomass resources.
Quantitative Real‐Time Monitoring of Antibody‐Induced Internalization of Epidermal Growth Factor Receptor on Single Living Mammalian Cells Using Scanning Electrochemical Microscopy
Authors: Matsumae Yoshiharu , Takahashi Yasufumi , Shiku Hitoshi , Matsue Tomokazu 
Published: July 2018

AbstractAn antibody‐induced internalization of epidermal growth factor receptor (EGFR) was quantitatively monitored using scanning electrochemical microscopy (SECM) at the single‐cell level. The antibody Cetuximab is used for cancer treatment because of its capability to bind and internalize EGFR, which is one of the key membrane proteins associated with many cancers. To monitor antibody‐induced EGFR internalization, Cetuximab was simply labelled with enzymes and the resulting enzymatic products were then electrochemically detected by using a microelectrode. By optimizing experimental parameters, such as immunostaining condition, enzyme type, and buffer solution, we were able to successfully monitor the EGFR internalization by using SECM, from which we found a decrease in current responses from a single living cell by 20 % in the first 60 min, suggesting different internalization pathways from inherent ligand‐induced internalization.
Chemical Synthesis of Bioactive Naturally Derived Cyclic Peptides Containing Ene‐Like Rigidifying Motifs
Authors: De Leon Rodriguez Luis M. , Williams Elyse T. , Brimble Margaret A. 
Published: July 2018

AbstractThe development of synthetic methods to prepare conformationally constrained peptides and peptide–polyketide hybrids remain an important chemical challenge. It is known that structural rigidity correlates with the specificity, bioactivity, and stability of these peptide systems, thus rigid systems are particularly attractive leads for development of potent biopharmaceuticals. Herein we provide an overview of recent developments in the syntheses of naturally derived constrained peptides and peptide–polyketide hybrids, with a particular emphasis on those systems containing an ene‐like bond.
Triazoles as T2‐Exchange Magnetic Resonance Imaging Contrast Agents for the Detection of Nitrilase Activity
Authors: Zhang Jia , Han Zheng , Lu Jiaqi , Li Yuguo , Liao Xuhe , van Zijl Peter C. , Yang Xing , Liu Guanshu 
Published: July 2018

AbstractWe characterized the T2‐exchange (T2ex) magnetic resonance imaging (MRI) contrast of azole protons that have large chemical shifts from the water proton resonance as a function of pH, temperature, and chemical modification. Our results showed that 1,2,4‐triazoles could be tuned into excellent diamagnetic T2ex contrast agents, with an optimal exchange‐based relaxivity r2ex of 0.10 s−1 mm−1 at physiological pH and B0=9.4 T. A fit of r2ex data to the Swift–Connick equation indicated that imino proton exchange of triazoles is dominated by a base‐catalyzed process at higher pH values and an acid‐catalyzed process at lower pH. The magnitude of r2ex was also found to be heavily dependent on chemical modifications, that is, enhanced by electron‐donating groups, such as amines and methyls, or by intramolecular hydrogen bonding between the imino proton and the carboxyl, and weakened by electron‐withdrawing groups like bromo, cyano, and nitro. In light of these findings, we applied T2ex MRI to assess the activity of nitrilase, an enzyme catalyzing the hydrolysis of 1,2,4‐triazole‐3‐carbonitrile to 1,2,4‐triazole‐3‐carboxylic acid, resulting in the enhancement of R2ex. Our findings suggest that 1,2,4‐triazoles have potential to provide sensitive and tunable diagnostic probes for MRI.
Recent Advances in Aromatic Antimony Clusters
Authors: Li Lei‐Jiao , Ali Basharat , Chen Zhongfang , Sun Zhong‐Ming 
Published: July 2018

AbstractThis paper highlights the compounds containing Sb cluster fragments, either synthesized in the solid‐state, discovered from the gas phase, or only theoretically predicted. These Sbn clusters feature unique chemical bonding, fascinating structures, and special stabilities that can be well rationalized by aromaticity or antiaromaticity. A deep understanding to their electronic structures is essential and will greatly facilitate the experimental synthesis of new Sbn cluster‐based materials.