bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deterioration processes affecting prehistoric rock art engravings in granite in NW Spain
Authors: Pozo‐Antonio J.S. , Rivas T. , Carrera F. , García L. 
Published: May 2018

AbstractPrehistoric rock art sites are endangered despite conservation efforts. The lack of scientific documentation regarding weathering agents affecting rock art and the absence of specific diagnostic protocols hinder the development of conservation strategies. The aim of this research was to investigate active deterioration processes in a granite petroglyph site located in Mougás (Galicia, NW Spain) by characterizing the granite, conducting a geotechnical study of the outcrop and describing and analysing the main weathering processes. Two main deterioration factors were identified. First, water favours block disjunction at the massif scale and causes pitting and surface erosion at the millimetre scale that affects the readability of the engravings. Second, high temperatures associated with wildfires cause mineral transformations that increase the susceptibility of the rock to weathering. Identifying deterioration factors is a first step in developing appropriate preventive conservation measures, which should aim to reduce rock contact time with water (technically affordable in the short term) and to reduce the probability of wildfire occurrence (technically more complex and possibly with longer‐term results). Copyright © 2018 John Wiley & Sons, Ltd.
Provably secure and authenticated data sharing protocol for IoT‐based crowdsensing network
Authors: Karati Arijit , Biswas G. P. 
Published: May 2018

AbstractWith the rapid developments in embedded sensor technology, the internet of things (IoT) becomes the most focused research trend in the recent years. However, the integration of such technology into mobile crowdsensing networks results in many security challenges. Data confidentiality and authenticity are the two key privacy concerns in any IoT‐based crowdsensing environment. Focusing on these security issues, we present a new cryptographic protocol to meet those challenges. Our protocol is based on two new schemes; first is an encryption scheme, which utilizes the idea of identity‐based encryption, and the second is a designated verifier signature scheme. Here, we design a pairing‐free and random oracle‐free encryption scheme with a small‐size public parameter where the anonymity of IoT‐recipient is maintained. Besides, the proposed designated verifier signature scheme facilitates the signatory to send a signature without sending the original message. The security of the encryption and signature schemes are proven in the standard security model based on the difficulty of proposed modified interactive quadratic residuosity “(MIQR)” assumption. Moreover, the schemes are compared with other relevant schemes and found several merits in terms of functionality. Thus, the proposed protocol is applicable in many IoT‐enabled crowdsourcing environments where the authenticity of confidential data is the major concern.
Batch‐based security‐aware spectrum sharing with simultaneous assignment decisions in time‐critical IoT networks with cognitive radio capabilities
Authors: Bany Salameh Haythem , Almajali Sufyan , Ayyash Moussa , Elgala Hany 
Published: May 2018

AbstractCognitive radio (CR) is considered as a key enabling communication technology that offers efficient wireless connectivity to Internet of Things (IoT) devices. Its integration with the future 5G architecture is expected to advance the IoT paradigm. Security attacks can severely degrade the performance of such CR‐based IoT (CRIoT) networks. The effect of security attacks can be reduced by implementing defensive approaches. However, such solutions come at the expense of degrading spectrum efficiency and consuming more network resources. In this paper, we investigate the spectrum sharing and access problem in a multidevice single‐transceiver CRIoT network with time‐critical applications under jamming attacks. Our main goal is to maximize the number of simultaneously served IoT devices over all available idle channels while ensuring delay requirement, hardware, link quality, security attacks, and spectrum utilization constraints. This problem is formulated as a total unimodular binary linear programming, which is shown to be solvable in polynomial time. Unlike most of previous security‐aware channel assignment solutions that conduct the channel assignment sequentially, our solution simultaneously provides secured distributed channel‐assignment decisions for multiple CRIoT links (batching method). Batching can be realized through an admission control stage for CR IoT devices to announce their control packets. Simulation results reveal that our solution significantly improves network performance compared to previous security‐aware schemes.
A unified performance analysis of decode‐and‐forward dual‐hop relaying‐based wireless energy harvesting with space modulation
Authors: Badarneh Osamah S. , Althunibat Saud , Mesleh Raed , Magableh Amer M. 
Published: May 2018

AbstractSpace modulation techniques (SMTs) are a group of multiple‐input–multiple‐output wireless systems in which the spatial indexes of transmit antennas are utilized to convey additional information bits. The SMTs promise significant enhancements in terms of spectral and energy efficiencies and attract significant research interest in literature. Several SMTs have been proposed including spatial modulation (SM) and quadrature SM. In this study, the performance of dual‐hop decode‐and‐forward relaying SM and quadrature SM in the presence of wireless power transfer is analyzed and thoroughly discussed. Specifically, we derive exact closed‐form expressions for the pairwise error probability (PEP). In addition, we derive simple and accurate asymptotic expressions for the PEP at high signal‐to‐noise ratio, which provides insight into the influence of different system parameters. The obtained PEP expressions are then employed to evaluate the overall average bit error rate (BER). It is worth highlighting that the derived expressions are unified in the sense that they are valid for the aforementioned SMTs and for two well‐known practical energy harvesting protocols, namely, power‐splitting receiver and time‐switching receiver. In addition, we derive a unified closed‐form expressions for the outage probability and achievable throughput at the destination node. The impact of diverse system parameters, such as the power‐splitting factor, the energy‐harvesting time factor, and the distance between the source and the relay nodes, on the overall system performance is studied. The accuracy of the analytical derivations is validated through Monte Carlo simulations results.
From funding liquidity to market liquidity: Evidence from the index options market
Authors: Liu Chunbo , Zhang Cheng , Zhou Zhiping 
Published: May 2018

AbstractThis study examines the relationship between funding liquidity and market liquidity using daily data on the S&P 500 index options. We find that options market liquidity is positively correlated with funding liquidity after controlling for market uncertainty. Further analysis reveals that the positive relationship between funding liquidity and market liquidity in the options market is mainly driven by short‐term and deep out‐of‐the‐money options. Our results remain robust after controlling for the confounding effects of the equity market and different data frequencies.
The deletion of dicer in mature myelinating glial cells causes progressive axonal degeneration but not overt demyelination in adult mice
Authors: Li Tao , Wang Jingjing , Wang Hongkai , Yang Yujian , Wang Shouyu , Huang Nanxin , Wang Fei , Gao Xing , Niu Jianqin , Li Zhifang , Mei Feng , Xiao Lan 
Published: May 2018

AbstractMyelinating glial cells (MGCs), oligodendrocytes (OLs) in the central nervous system (CNS) and Schwann cells (SCs) in the peripheral nervous system (PNS), generate myelin sheaths that insulate axons. After myelination is completed in adulthood, MGC functions independent from myelin are required to support axon survival, but the underlying mechanisms are still unclear. Dicer is a key enzyme that is responsible for generating functional micro‐RNAs (miRNAs). Despite the importance of Dicer in initiating myelination, the role of Dicer in mature MGCs is still unclear. Here, Dicer was specifically deleted in mature MGCs in 2‐month old mice (PLP‐CreERT; Dicer fl/fl) by tamoxifen administration. Progressive motor dysfunction was observed in the Dicer conditional knockout mice, which displayed hind limb ataxia at 3 months post recombination that deteriorated into paralysis within 5 months. Massive axonal degeneration/atrophy in peripheral nerves was responsible for this phenomenon, but overt demyelination was not observed in either the CNS or PNS. In contrast to the PNS, signs of axonal degeneration were not observed in the CNS of these animals. We induced a Dicer deletion in oligodendroglia at postnatal day 5 in NG2‐CreERT; Dicer fl/fl mice to evaluate whether Dicer expression in OLs is essential for axonal survival. Dicer deletion in oligodendroglia did not cause motor dysfunction at the age of 7 months. Neither axonal atrophy nor demyelination was observed in the CNS. Based on our results, Dicer expression in SCs is required to maintain axon integrity in adult PNS, and Dicer is dispensable for maintaining myelin sheaths in MGCs.
USING SINGLE‐CASE DESIGNS TO EVALUATE COMPONENTS OF TRIBAL HOME‐VISITATION PROGRAMS
Authors: Chomos Julianna C. , Evans William P. , Bolan Marc , Merritt Lindsay , Meyer Aleta , Novins Douglas K. 
Published: May 2018

ABSTRACTSingle‐case designs are typically used in classroom and clinical settings to assess the behavioral impacts of an intervention with an individual child. Using two illustrative case studies, this article describes the extension of this model to home‐visitation programs serving tribal communities and examines the lessons learned throughout the process of adapting this approach. Our experience suggests that the benefits of using this design outweigh the associated challenges and allows researchers to expand the use of single‐case designs to previously unexplored settings. Specifically, some of the benefits discussed include allowing for evaluative rigor in contexts with small samples, allowing everyone who qualifies to immediately participate, providing visual representations of the outcome—making the results more tangible and accessible to a broader audience, and allowing for a deep level of cultural sensitivity. The article also provides some general guidelines to address the practical challenges one may face when attempting to use single‐case designs in novel ways within nonschool settings.
Integrated microRNA and mRNA sequencing analysis of age‐related changes to mouse thymic epithelial cells
Authors: Jia Hong‐Ling , Zeng Xiao‐Qin , Huang Feng , Liu Ya‐Meng , Gong Bi‐Shuang , Zhang Kai‐Zhao , Zeng Jiang‐Hui , Guo Dong‐Guang , Wang Zhuo‐Ya , Li Yu‐Gu 
Published: May 2018

AbstractMicroRNAs (miRNAs) play key roles in the regulation of gene expression during multiple physiological processes, including early development, differentiation, and ageing. However, their involvement in age‐related thymic involution is not clear. In this study, we profiled the global transcriptome and miRNAome of thymic epithelial cells in 1‐ and 3‐month‐old male and female mice, and predicted the possible transcription factors and target genes of the four most significantly differentially expressed miRNAs (DEMs) (miR‐183‐5p, miR‐199b‐5p, miR‐205‐5p, and miR‐200b‐3p) by performing bioinformatics analyses. We also evaluated the relationships between the significantly DEMs and mRNAs. We performed quantitative polymerase chain reaction to confirm the changes in the expression of the miRNAs and their predicted target genes. We found that miR‐183‐5p, miR‐199b‐5p, miR‐205‐5p, and miR‐200b‐3p can be used as a biomarker group for mouse thymus development and involution. In addition, the predicted target genes (Ptpn4, Slc2a9, Pkib, Pecam1, and Prkdc), which were identified by mRNA sequencing analysis, were mainly involved in growth, development, and accelerated senescence. In conclusion, miRNAs and their predicted target genes likely play important roles in thymus development and involution. To the best of our knowledge, this is the first study to systematically analyze the relevance of miRNAs and their targets by mRNA sequencing in mouse thymic epithelial cells. © 2018 IUBMB Life, 70(7):678–690, 2018
Injectable hydrogels and nanocomposite hydrogels for cartilage regeneration
Authors: Jeznach Oliwia , Kołbuk Dorota , Sajkiewicz Pawe 
Published: May 2018

AbstractCartilage loss due to age‐related degeneration and mechanical trauma is a significant and challenging problem in the field of surgical medicine. Unfortunately, cartilage tissue can be characterized by the lack of regenerative ability. Limitations of conventional treatment strategies, such as auto‐, allo‐, and xenografts or implants stimulate an increasing interest in the tissue engineering approach to cartilage repair. This review discusses the application of polymer‐based scaffolds, with an emphasis on hydrogels in cartilage tissue engineering. We highlight injectable hydrogels with various micro‐ and nanoparticles, as they constitute a novel and attractive type of scaffolds. We discuss advantages, limitations, and future perspectives of injectable nanocomposite hydrogels for cartilage tissue regeneration. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2762–2776, 2018.
Effect of compliance during periodontal maintenance therapy on levels of bacteria associated with periodontitis: A 6‐year prospective study
Authors: Costa Fernando Oliveira , Vieira Thaís Riberal , Cortelli Sheila Cavalca , Cota Luís Otávio Miranda , Costa José Eustáquio , Aguiar Maria Cássia Ferreira , Cortelli José Roberto 
Published: May 2018

AbstractBackgroundIt is well established that regular compliance during periodontal maintenance therapy (PMT) maintains the stability of periodontal clinical parameters obtained after active periodontal therapy (APT). However, compliance during PMT has not yet been related to subgingival bacterial levels. Thus, this study followed individuals in PMT over 6 years and longitudinally evaluated the effects of compliance on periodontitis‐associated bacterial levels and its relation to periodontal status.MethodsFrom a 6‐year prospective cohort study with 212 individuals in PMT, 91 were determined to be eligible. From this total, 28 regular compliers (RC) were randomly selected and matched for age and sex with 28 irregular compliers (IC). Complete periodontal examination and microbiological samples were obtained 5 times: T1 (prior to APT), T2 (after APT), T3 (2 years), T4 (4 years), and T5 (6 years). Total bacteria counts and levels of Actinomyces naeslundii, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were evaluated through quantitative polymerase chain reaction.ResultsRC had less tooth loss and better clinical and microbiological conditions over time when compared with IC. IC had higher total bacterial counts and higher levels of T. denticola. Moreover, among IC, total bacterial counts were positively associated with plaque index and bleeding on probing, while levels of A. naeslundii, T. forsythia, and T. denticola were negatively associated with clinical attachment loss (4 to 5 mm) among RC.ConclusionsCompliance positively influenced subgingival microbiota and contributed to stability of periodontal clinical status. Regular visits during PMT sustained microbiological benefits provided by APT over a 6‐year period.
1,25‐dihydroxyvitamin D deficiency accelerates alveolar bone loss independent of aging and extracellular calcium and phosphorus
Authors: Gong Aixiu , Chen Jie , Wu Jun , Li Jing , Wang Lin , Goltzman David , Miao Dengshun 
Published: May 2018

AbstractBackgroundVitamin D is critical for bone homeostasis and immunomodulation. We therefore assessed whether 1,25‐dihydroxyvitamin D (1,25(OH)2D) deficiency in mice with targeted deletion of the gene encoding 25‐hydroxyvitamin D‐1α‐hydroxylase (1α(OH)ase [1αOH)ase−/−mice]) results in alveolar bone loss and periodontal inflammation in vivo.MethodsTen‐week‐old and 12‐month‐old 1α(OH)ase−/−mice and wild‐type littermates were fed a normal diet or a rescue diet, and the phenotype of the periodontium was then analyzed using microcomputed tomography, histology, immunohistochemistry, and real‐time Reverse transcription‐polymerase chain reaction (RT‐PCR).ResultsAlveolar bone loss was increased and maxillary bone mineral density (BMD), osteoblast numbers, and the number of osterix‐positive cells were decreased significantly in 1α(OH)ase−/−mice compared with wild‐type mice. Although aging from 10 weeks to 12 months accentuated these changes, and a rescue diet reduced them, the alterations in the 1α(OH)ase−/−mice exceeded the effects of aging and diet change. Nuclear factor kappa light‐chain‐enhancer of activated B cells (NF‐кB) p65 and CD3 positive cells, and the gene expression levels of interleukin (IL)‐1β, tumor necrosis factor (TNF)‐α, matrix metalloproteinase (MMP)‐3 and ‐8 were all increased significantly in periodontal tissues of 1α(OH)ase−/−mice compared with wild‐type mice. Aging from 10 weeks to 12 months also accentuated these changes, and a rescue diet reduced them, however, the alterations in the 1α(OH)ase−/−mice exceeded the effects of aging and diet change.Conclusion1,25(OH)2D deficiency in the 1α(OH)ase−/−mice accelerated alveolar bone loss by inhibiting osteoblastic bone formation and enhancing periodontal tissue degeneration in a calcium‐ and phosphorus‐ as well as an age‐independent manner.
Annexin‐1 as a salivary biomarker for gingivitis during pregnancy
Authors: Hassan Manar N. , Belibasakis Georgios N. , Gumus Pinar , Öztürk Veli Özgen , Emingil Gulnur , Bostanci Nagihan 
Published: May 2018

AbstractBackgroundIt is well established that there is higher susceptibility to gingival inflammation during pregnancy. Annexin‐1 (ANXA1) is an anti‐inflammatory protein which has been identified in gingival tissue exudates by discovery proteomics. This cross‐sectional case‐control study investigated the levels and association of ANXA1 and pro‐inflammatory mediator interleukin (IL)‐1β in the saliva of pregnant and non‐pregnant women.MethodsWhole unstimulated saliva from 69 non‐pregnant and 78 pregnant women was collected prior to measurement of probing depth, clinical attachment level, bleeding on probing, and plaque. Then, the women were split into 3 subgroups depending on their periodontal status (healthy, gingivitis, and periodontitis). The levels of ANXA1 and IL‐1β were measured with enzyme‐linked immunosorbent assay and reported as pg/mg after normalizing against the total protein levels.ResultsSignificantly higher ANXA1 levels were exhibited in pregnant women with gingivitis compared with health (P < 0.05) and in pregnant women with gingivitis compared with the respective non‐pregnant group (P < 0.0001). There was a significantly higher level of IL‐1β in gingivitis than in health in pregnant women (P < 0.05) and significantly higher levels in periodontitis compared with health in non‐pregnant women (P < 0.05). Looking at the IL‐1 β:ANXA1 ratio, the non‐pregnant periodontitis group displayed a significantly higher ratio compared with the respective pregnant group (P < 0.05). In the non‐pregnant subpopulation, the ratio was significantly higher in periodontitis compared with health (P < 0.01).ConclusionSalivary ANXA1 levels are elevated in the presence of gingivitis only in pregnant, but not non‐pregnant women, rendering this molecule as a potential salivary biomarker for non‐invasive early screening for gingival inflammation during pregnancy.
Patagonian ash on sub‐Antarctic South Georgia: expanding the tephrostratigraphy of southern South America into the Atlantic sector of the Southern Ocean
Authors: Oppedal Lea Toska , van der Bilt Willem G. M. , Balascio Nicholas L. , Bakke Jostein 
Published: May 2018

ABSTRACTFingerprinting non‐visible volcanic ash (cryptotephra) enables precise dating and time synchronization of palaeoclimate archives. Recent analytical advances allow us to strengthen and expand existing tephrostratigraphical frameworks and harness the full potential of this powerful geochronological tool. Here, we present geochemical (electron microprobe) and chronological (14C) evidence to show that ash found in a peat section on the sub‐Antarctic island of South Georgia correlates to the ∼2950 cal a BP Alpehué eruption of the Chilean Sollipulli volcano. This discovery marks the first tephra fingerprint on South Georgia and expands the recently refined tephrostratigraphy of Patagonia ∼3000 km into the Southern Ocean. As deposition of this tephra horizon coincides with a major shift in regional atmospheric conditions, future finds may yield information on the spatiotemporal pattern of Southern Ocean climate dynamics.
Coastal zones as important habitats of coccolithophores: A study of species diversity, succession, and life‐cycle phases
Authors: Godrijan Jelena , Young Jeremy R. , Marić Pfannkuchen Daniela , Precali Robert , Pfannkuchen Martin 
Published: May 2018

AbstractCoccolithophores are unicellular calcifying eukaryotes with a complex life‐cycle; they are important primary producers, and major drivers of global biogeochemical cycles. The majority of research on coccolithophores has been focused on open ocean waters, while the knowledge of their roles in coastal ecosystems is limited. Early 20thcentury studies of the Adriatic coast produced major taxonomic papers describing half of the projected diversity of coccolithophores. Afterwards, there have been only scarce records of their diversity and ecology in the Adriatic, and coastal systems in general. We aimed to assess coccolithophore diversity and species succession, and closely examine their ecological preferences in the coastal area of the northern Adriatic. We recorded coccolithophores throughout the year at 100% frequency, documented 52 taxa, abundances as high as 2.4 × 105cells L−1, and noted the winter domination over the phytoplankton community. Out of 52 observed coccolithophore taxa, 31 were heterococcolithophorids and 21 holococcolithophorids. Moreover, seven pairs of heterococcolith and holococcolith phases were noted, and two strategies of temporal separation of life‐cycle phases were observed. We report ecological preferences of those life‐cycle pairs and give in situ evidence that holo‐ and heterococcolith phases are widening the specie's ecological niches. This expansion allows the species to exploit a wider range of ecological conditions and enables phenotypic plasticity, important in response to changes in the environment. With this study we emphasize that coastal areas are highly productive for coccolithophore studies. Our results indicate that a shift in research effort on coccolithophores in the coastal waters is needed.