bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil Based Heavy Metals Originating from Anthropogenic Activities on Floristic Composition of Some Selected Sites in Kaduna Northern Guinea Savanna of Nigeria
Authors: Sodimu A. I. , Onwumere G. B. , Yilwa V. M. 
Published: October 2019

Soil based heavy metals originating from anthropogenic activities on floristic composition of some selected sites in Northern Guinea savanna of Nigeria were investigated. 50m x 50m plots were laid in each of the three (3) selected sites with 30m espacement between each plot. This is replicated three (3) times to make a total of nine (9) plots in all. Soil samples were collected at a depth of 25m with a soil auger and heavy metal analysis was carried out with the use of atomic absorption spectrophotometer. The floristic compositions were evaluated using line transect method. Flora were enumerated in all the sites irrespective of the growth form, (i.e. trees, shrubs and herbs). The data collected were subjected to descriptive statistic, Anova using SPSS while the diversity index was calculated using Shannon Weiner method. The study revealed the presence of six (6) soil based metals in the selected sites, Cd; Cu; Mn; Ni; V and Zn. Significance differences (P<0.05) exist in soil based heavy metal between sites. A total of two thousand two hundred and sixty one (2,261) floral species were evaluated. The population densities of the floristic composition are higher in site A than all the other sites while species diversity decrease significantly (P<0.05) from Site A to C. It is concluded that population densities and diversity of the floristic composition in the selected sites are influenced as a result of soil based heavy metals originating from anthropogenic activities in the sites. It is however recommended that there should be provision of guidelines for the abatement of pollution establishing standard for the control of fuel additives with respect to heavy metals. Also, there should be prescribed standard for the level of emission from automobile exhaust and energy generating plants and stations.
Evaluation of the Antihyperglycemic Effect of N-butanol Leaves Extracts of Iraqi Fumaria parviflora in Alloxan-prompt Diabetic Rats
Authors: Kadheem Enas Jawad , Hussein Ahmed Omar 
Published: October 2019

Objective: In this research, we evaluated the antihyperglycemic effect of leaves of Fumaria parviflora (F. parviflora) and implied mechanisms by using in vivo models of hyperglycemia.
Materials and Methods: Fifty male Wistar rats weighing 180-220 g were applied for the research. Soxhlet ethanolic extract of leaves of F. parviflora (EFP ) was prepared. Alloxan-induced diabetic rats were orally remedied with the extract (50, 100 or 200 mg/kg/day), metformin (200 mg/kg/day) for two weeks. Another animal received only extract, alloxan (diabetic control) or vehicle (control).
Results: pretreatment effect of plant extract on blood glucose levels of diabetic rats Blood glucose levels in all extract pretreated groups was lower (p<0.05) when compared with the levels in rats that received alloxan alone, Rats that we are treated with plant extract had normal blood glucose levels that ranged for 73.00±1.5 to76.00±0.54 mg/dl at the beginning (first day) of experiment. Blood glucose levels in these animals declined during the period of extract administration, but the values obtained were not significant compared to control excluded those that were obtained on the 14th day, p < 0.05
Conclusion: Leaves of F. parviflora possess blood glucose-lowering effects In Alloxan-Induced Diabetic Rat, The findings of a study indicated that F. parviflora has a significant hypoglycemic effect on Alloxan-induced diabetic rats with no effects in blood glucose levels of normal rats.
Expanded amino acid sequence of the PhaC box in the active center of polyhydroxyalkanoate synthases
Authors: Nambu Yuka , Ishii‐Hyakutake Manami , Harada Ken , Mizuno Shoji , Tsuge Takeharu 
Published: October 2019

Polyhydroxyalkanoate (PHA) synthases catalyze the polymerization reaction of the acyl moiety of hydroxyacyl‐coenzyme A into polyester. The catalytic subunit PhaC of PHA synthase has the PhaC box sequence at the active site that is typically described as G‐X‐C‐X‐G‐G (X is an arbitrary amino acid), and cysteine is an active center. In this study, an amino acid replacement was introduced into the PhaC box of the PHA synthase derived from Ralstonia eutropha (PhaCRe) to investigate the importance of highly conserved residues in polymerizing activity. Point mutagenesis revealed that PhaCRe mutants with the expanded PhaC box sequence ([GAST]‐X‐C‐X‐[GASV]‐[GA]) are functional PHA synthases. These findings highlight the low mutational robustness of the last glycine residue in the PhaC box as well as that of the active center cysteine.
Peak‐to‐Average Power Ratio Reduction Techniques
Authors: Guzmán Borja Genovés , Jiménez Víctor P. Gil , Pérez Roberto Pérez 
Published: October 2019

AbstractMulticarrier transmission schemes produce time‐domain (TD) signals with large envelope fluctuations. These signals suffer from nonlinear distortions when passing through a high‐power amplifier (HPA) because of its nonlinear transfer function. Several metrics are used to quantify the envelope fluctuations: peak‐to‐average power ratio (PAPR), crest factor (CF), and cubic metric (CM). Multiple techniques and algorithms have been proposed for reducing such metrics in the literature. This article reviews all the possible PAPR reduction techniques and emphasizes the importance of their application in multicarrier schemes. Besides, new variants adapted to multiple‐input multiple‐output (MIMO) orthogonal frequency division multiplexing (OFDM) are also presented, which take on importance in 5G systems. Finally, a comparison among these techniques is presented in terms of the key aspects considered when designing a 5G system: power increase, implementation complexity, bit error rate (BER) degradation, and required side information. It is shown that the selection of the PAPR reduction technique depends on the application, the system requirements, and the scenario.
Advanced Functional Materials and Cell‐Based Therapies for the Treatment of Ischemic Stroke and Postischemic Stroke Effects
Authors: Tapeinos Christos , Larrañaga Aitor , Tomatis Francesca , Bizeau Joëlle , Marino Attilio , Battaglini Matteo , Pandit Abhay , Ciofani Gianni 
Published: October 2019

AbstractIschemic stroke is considered one of the most threatening neurological disorders with high percentages of mortality and morbidity worldwide. Although in recent years, several nanotechnological advances have improved the survival rates, severe untreated poststroke side‐effects continue to significantly influence the way of life of many. Tissue plasminogen activator and mechanical thrombectomy are considered the gold standards for the treatment of acute cerebral ischemia. These, however, fail to improve postischemic disorders. Herein, after a brief description of the pathophysiology of ischemic stroke and the following biochemical cascade, the most recent biomaterial and cell‐based strategies are reviewed for its treatment. Other therapeutics that have been proposed not only for the treatment of cerebral ischemia but also for the regeneration of the infarcted brain that is responsible for a variety of disorders, including cognitive, motor, and speech problems are also presented. Finally, a few reported studies on diagnostic and theranostic nanostructures are also provided.
Fabrication of Curcumin‐Modified TiO2 Nanoarrays via Cyclodextrin Based Polymer Functional Coatings for Osteosarcoma Therapy
Authors: Zhang Meng , Zhang Jiting , Chen Jisheng , Zeng Yan , Zhu Zhihong , Wan Ying 
Published: October 2019

AbstractThe incomplete removal of bone tumors leads to increased local recurrence and poor prognosis. To prevent ostoperative tumor recurrence and simultaneously repair surgery‐caused bone defects, there is a need of great significance to develop implantable biomaterials possessing both cancer cell‐killing ability and excellent bioactivity. In this work, a functionalized titanium‐based implant is successfully fabricated by loading curcumin (CUR) onto cyclodextrin based polymer (pCD) modified titanium dioxide (TiO2) nanorod arrays. Herein, a polydopamine (pDA) assisted film is implemented as a first coating layer onto the surface of the TiO2 nanoarrays to guarantee the robust anchorage of the pCD. The pCD coating acts as a reservoir for CUR, allowing for efficient drug loading and sustained release of anticancer drugs. Studies show that the CUR‐modified surfaces (TiO2/pDA/pCD/CUR) can significantly promote apoptosis of osteosarcoma cells in vitro by inducing mitochondrial dysfunction caused by the ROS overproduction, and meanwhile, effectively inhibit the tumor growth in vivo. Moreover, such functionalized implants with surface density of loaded CUR at 22.48 µg cm−2 or lower support the attachment and proliferation of osteoblasts in vitro. These results successfully demonstrate that as‐prepared TiO2/pDA/pCD/CUR constructs have combined anticancer performance and good biocompatibility, which has great promise for the surgical therapy of bone tumors.
Recent Advances in Nanostrategies Capable of Overcoming Biological Barriers for Tumor Management
Authors: Huo Da , Jiang Xiqun , Hu Yong 
Published: October 2019

AbstractEngineered nanomaterials have been extensively employed as therapeutics for tumor management. Meanwhile, the complex tumor niche along with multiple barriers at the cellular level collectively hinders the action of nanomedicines. Here, the advanced strategies that hold promise for overcoming the numerous biological barriers facing nanomedicines are summarized. Starting from tumor entry, methods that promote tissue penetration of nanomedicine and address the hypoxia issue are also highlighted. Then, emphasis is given to the significance of overcoming both physical barriers, such as membrane‐associated efflux pumps, and biological features, such as resistance to apoptosis. The pros and cons for an individual approach are presented. In addition, the associated technical problems are discussed, along with the importance of balancing the therapeutic merits and the additional cost of sophisticated nanomedicine designs.
Intelligent Metamaterials Based on Nonlinearity for Magnetic Resonance Imaging
Authors: Zhao Xiaoguang , Duan Guangwu , Wu Ke , Anderson Stephan W. , Zhang Xin 
Published: October 2019

AbstractMetamaterials provide a powerful platform to probe and enhance nonlinear responses in physical systems toward myriad applications. Herein, the development of a coupled nonlinear metamaterial (NLMM) featuring a self‐adaptive response that selectively amplifies the magnetic field is reported. The resonance of the NLMM is suppressed in response to higher degrees of radio‐frequency excitation strength and recovers during a subsequent low excitation strength phase, thereby exhibiting an intelligent, or nonlinear, behavior by passively sensing excitation signal strength and responding accordingly. The nonlinear response of the NLMM enables us to boost the signal‐to‐noise ratio during magnetic resonance imaging to an unprecedented degree. These results provide insights into a new paradigm to construct NLMMs consisting of coupled resonators and pave the way toward the utilization of NLMMs to address a host of practical technological applications.
Regio‐ and Stereoselective Synthesis of Enynyl Boronates via Ruthenium‐Catalyzed Hydroboration of 1,4‐Diaryl‐Substituted 1,3‐Diynes
Authors: Sokolnicki Tomasz , Szyling Jakub , Franczyk Adrian , Walkowiak Jędrzej 
Published: October 2019

AbstractA facile ruthenium‐catalyzed regio‐ and stereoselective hydroboration of symmetrical, aromatic 1,3‐diynes with pinacolborane towards 2‐boryl‐1,4‐diaryl‐buta‐1‐en‐3‐ynes and their further transformation into potassium trifluoroborate salts is presented. The reaction proceeded efficiently for 1,4‐diphenylbutadiynes with various substituents on the phenyl rings and heterocyclic 1,4‐di(thiophen‐3‐yl)buta‐1,3‐diyne. The resulting products were isolated and fully characterized (1H, 13C, 11B and 1D NOESY NMR, IR, GC‐MS, HRMS or elemental analysis). Moreover, the crystal structure of an enynyl boronate was determined, proving the addition of boryl moiety at the internal carbon in the diyne, according to the anti‐Markovnikov rule. The results presented here are the first examples of selective catalytic monohydroboration of conjugated diynes. The products obtained due to the presence of the boryl group and the unsaturated bonds are potential synthons in the synthesis of natural compounds or active pharmaceutical ingredients (API). The model Suzuki coupling of 2‐boryl‐1,4‐diphenyl‐buta‐1‐en‐3‐ynes with iodobenzene was carried out to illustrate the utility of the resulting compounds.magnified image
A Flexible Solid‐State Aqueous Zinc Hybrid Battery with Flat and High‐Voltage Discharge Plateau
Authors: Liu Zhuoxin , Yang Qi , Wang Donghong , Liang Guojin , Zhu Youhuan , Mo Funian , Huang Zhaodong , Li Xinliang , Ma Longtao , Tang Tiancheng , Lu Zhouguang , Zhi Chunyi 
Published: October 2019

AbstractThe migration of zinc‐ion batteries from alkaline electrolyte to neutral or mild acidic electrolyte promotes research into their flexible applications. However, discharge voltage of many reported zinc‐ion batteries is far from satisfactory. On one hand, the battery voltage is substantially restricted by the narrow voltage window of aqueous electrolytes. On the other hand, many batteries yield a low‐voltage discharge plateau or show no plateau but capacitor‐like sloping discharge profiles. This impacts the battery's practicability for flexible electronics where stable and consistent high energy is needed. Herein, an aqueous zinc hybrid battery based on a highly concentrated dual‐ion electrolyte and a hierarchically structured lithium‐ion‐intercalative LiVPO4F cathode is developed. This hybrid battery delivers a flat and high‐voltage discharge plateau of nearly 1.9 V, ranking among the highest reported values for all aqueous zinc‐based batteries. The resultant high energy density of 235.6 Wh kg−1 at a power density of 320.8 W kg−1 also outperforms most reported zinc‐based batteries. A designed solid‐state and long‐lasting hydrogel electrolyte is subsequently applied in the fabrication of a flexible battery, which can be integrated into various flexible devices as powerful energy supply. The idea of designing such a hybrid battery offers a new strategy for developing high‐voltage and high‐energy aqueous energy storage systems.
Confined Fe2VO4⊂Nitrogen‐Doped Carbon Nanowires with Internal Void Space for High‐Rate and Ultrastable Potassium‐Ion Storage
Authors: Yang Chao , Lv Fan , Zhang Yelong , Wen Jie , Dong Kang , Su Hai , Lai Feili , Qian Guoyu , Wang Wei , Hilger André , Xu Yunhua , Zhu Yizhou , Deng Yida , Hu Wenbin , Manke Ingo , Chen Yanan 
Published: October 2019

AbstractDeveloping low‐cost, high‐capacity, high‐rate, and robust earth‐abundant electrode materials for energy storage is critical for the practical and scalable application of advanced battery technologies. Herein, the first example of synthesizing 1D peapod‐like bimetallic Fe2VO4 nanorods confined in N‐doped carbon porous nanowires with internal void space (Fe2VO4⊂NC nanopeapods) as a high‐capacity and stable anode material for potassium‐ion batteries (KIBs) is reported. The peapod‐like Fe2VO4⊂NC nanopeapod heterostructures with interior void space and external carbon shell efficiently prevent the aggregation of the active materials, facilitate fast transportation of electrons and ions, and accommodate volume variation during the cycling process, which substantially boosts the rate and cycling performance of Fe2VO4. The Fe2VO4⊂NC electrode exhibits high reversible specific depotassiation capacity of 380 mAh g−1 at 100 mA g−1 after 60 cycles and remarkable rate capability as well as long cycling stability with a high capacity of 196 mAh g−1 at 4 A g−1 after 2300 cycles. The first‐principles calculations reveal that Fe2VO4⊂NC nanopeapods have high ionic/electronic conductivity characteristics and low diffusion barriers for K+‐intercalation. This study opens up new way for investigating high‐capacity metal oxide as high‐rate and robust electrode materials for KIBs.
Aging Effect of a Cu(In,Ga)(S,Se)2 Absorber on the Photovoltaic Performance of Its Cd‐Free Solar Cell Fabricated by an All‐Dry Process: Its Carrier Recombination Analysis
Authors: Chantana Jakapan , Nishimura Takahito , Kawano Yu , Suyama Naoki , Yamada Akira , Kimoto Yoshinori , Kato Takuya , Sugimoto Hiroki , Minemoto Takashi 
Published: October 2019

AbstractCd‐free Cu(In,Ga)(S,Se)2 (CIGSSe) solar cells are fabricated by an all‐dry process (a Cd‐free and all‐dry process CIGSSe solar cell) with aged CIGSSe thin film absorbers. The aged CIGSSe thin films are kept in a desiccator cabinet under partial pressure of oxygen of ≈200 Pa for aging time up to 10 months. It is reported for the first time that aged CIGSSe thin film with increased aging time results in significant enhancement of photovoltaic performance of Cd‐free and all‐dry process CIGSSe solar cells, regardless of the alkali treatment. Based on carrier recombination analysis, carrier recombination rates at the interface and in the depletion region of the Cd‐free and all‐dry process CIGSSe solar cells are reduced owing to avoidance of sputtering damage on CIGSSe absorber surface, which is consistent with the strong electron beam‐induced current signal near CIGSSe surface after the increased aging time. It is implied that the interface and near‐surface qualities are clearly improved through the increased aging time, which is attributable to the self‐forming of Inx(O,S)y near CIGSSe surface, which acts as a buffer layer. Ultimately, the 22.0%‐efficient Cd‐free CIGSSe solar cell fabricated by all‐dry process is achieved with the aged Cs‐treated CIGSSe absorber with the aging time of 10 months.
Admixture in Mammals and How to Understand Its Functional Implications
Authors: Fontsere Claudia , de Manuel Marc , Marques‐Bonet Tomas , Kuhlwilm Martin 
Published: October 2019

AbstractAdmixture, the genetic exchange between differentiated populations appears to be common in the history of species, but has not yet been comparatively studied across mammals. This limits the understanding of its mechanisms and potential role in mammalian evolution. The authors want to summarize the current knowledge on admixture in non‐human primates, and suggest that it is important to establish a comparative framework for this phenomenon in humans. Genetic observations in domesticated mammals and their wild counterparts are discussed, and a brief global overview on other clades is presented. Based on this, some of the consequences of gene flow, including incompatibilities and their genomic footprint, as well as adaptive introgression are discussed, and suggestions for a functional genomics approach are made. It is proposed that the field is moving beyond descriptive observations in single species, to a comprehensive analysis of admixture and its impact. Admixture is becoming an integral part of mammalian evolution.
Effects of serum from breast cancer surgery patients receiving perioperative dexmedetomidine on breast cancer cell malignancy: A prospective randomized controlled trial
Authors: Liu Yan , Sun Jiaxin , Wu Tong , Lu Xiaoying , Du Yueyao , Duan Hongwei , Yu Weifeng , Su Diansan , Lu Jinsong , Tian Jie 
Published: October 2019

AbstractAdrenergic receptors (ARs) have gained attention for their involvement in breast cancer (BC) progression. Dexmedetomidine, a selective α2‐AR agonist, has been reported to increase the malignancy of BC cells in vitro or stimulate tumor growth in mice. However, clinical evidence is lacking. Clinical research in this area is important as dexmedetomidine is widely used in BC surgery patients. Here we allocated 24 women with primary BC to the dexmedetomidine group (who received a total dose of 2 μg kg−1 dexmedetomidine perioperatively) or to the control group (who received the same volume of normal saline). Venous blood was obtained from all patients immediately upon entering the operating room and 24 hours postoperatively. Serum was then exposed to MCF‐7 cells at a concentration of 10% for 24 hours. Cell proliferation, migration, and invasion were analyzed using EdU, Transwell, and Matrigel methods, respectively. We found that postoperative serum from those who received dexmedetomidine was associated with significantly increased cell proliferation, migration, and invasion compared with preoperative serum when used to culture MCF‐7 cells. The mean percentage change from post to preoperative values in these cell functions was significantly larger in the dexmedetomidine group than in the control group (proliferation, 30.44% vs 8.45%, P = .0024; migration, 15.90% vs 3.25%, P = .0015; invasion, 8.17% vs 2.13%, P = .04). In conclusion, these findings suggest that in patients undergoing surgery for primary BC, perioperative administration of dexmedetomidine might influence the serum milieu in a way that favors the malignancy of MCF‐7 cells.Clinical trial registration: NCT03108937.
Worse characteristics can predict survival effectively in bilateral primary breast cancer: A competing risk nomogram using the SEER database
Authors: Shen Kaiwen , Yao Longdi , Wei Jinli , Luo Zhou , Yu Wang , Zhai Huamin , Wang Jianwen , Chen Luhong , Fu Deyuan 
Published: October 2019

AbstractObjectiveThere is limited information from population‐based cancer registries regarding prognostic features of bilateral primary breast cancer (BPBC).MethodsFemale patients diagnosed with BPBC between 2004 and 2014 were randomly divided into training (n = 7740) and validation (n = 2579) cohorts from the Surveillance, Epidemiology, and End Results Database. We proposed five various models. Multivariate Cox hazard regression and competing risk analysis were to explore prognosis factors in training cohort. Competing risk nomograms were constructed to combine significant prognostic factors to predict the 3‐year and the 5‐year survival of patients with BPBC. At last, in the validation cohort, the new score performance was evaluated with respect to the area under curve, concordance index, net reclassification index and calibration curve.ResultsWe found out that age, interval time, lymph nodes invasion, tumor size, tumor grade and estrogen receptor status were independent prognostic factors in both multivariate Cox hazard regression analysis and competing risk analysis. Concordance index in the model of the worse characteristics was 0.816 (95% CI: 0.791‐0.840), of the bilateral tumors was 0.819 (95% CI: 0.793‐0.844), of the worse tumor was 0.807 (0.782‐0.832), of the first tumor was 0.744 (0.728‐0.763) and of the second tumor was 0.778 (0.762‐0.794). Net reclassification index of the 3‐year and the 5‐year between them was 2.7% and −1.0%. The calibration curves showed high concordance between the nomogram prediction and actual observation.ConclusionThe prognosis of BPBC depended on bilateral tumors. The competing risk nomogram of the model of the worse characteristics may help clinicians predict survival simply and effectively. Metachronous bilateral breast cancer presented poorer survival than synchronous bilateral breast cancer.