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Tropical tree community composition and diversity variation along a volcanic elevation gradient

Journal of Mountain Science 2022年第12期19卷 3475-3486页

作者： Ruben MARTINEZ-CAMILO Manuel MARTINEZ-melENDEZ Nayely MARTINEZ-MIelENDEZ Derio Antonio JIMENEZ-LOPEZ Mauricio JOSE-RIOS Unidad Villa Corzo Facultad de IngenieríaUniversidad de Ciencias y Artes de Chiapas30520 Villa CorzoChiapasMexico Instituto de Ciencias Biológicas Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico Eizia A.C. 29045 Tuxtla GutiérrezChiapasMexico Departamento de Conservación de la Biodiversidad El Colegio de la Frontera Sur29290 San Cristóbal de las CasasChiapasMexico Orquidiario y Jardín Botánico de Comitán Secretaría de Medio Ambiente e Historia Natural30106 Comitán de DomínguezChiapasMexico Instituto de Investigación en Gestión de Riesgos y Cambio Climático Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico

Unraveling the factors that determine variation of diversity in tropical mountain systems is a topic for debate in plant *** is especially true in areas where topography is complex due to volcano elevational gradients and where forests are vulnerable to human *** this study we used a set of climatic(temperature,rainfall,and radiation solar),topographic(elevation,slope aspect,and slope orientation)and human disturbance variables to determine their effect on diversity and composition patterns of a tree community,considering three slope aspects of a tropical volcano in southeastern *** sampled trees in seventy 0.1-ha plots distributed on three slope aspects of the Tacanávolcano along an elevational gradient of 1500 to 2500 *** determined diversity patterns(general tree richness,exponential of Shannon index,and pioneer species richness)with linear regression models,and for beta diversity,we used a dissimilarity index(within and between elevational bands 100 m wide).The effect of a set of environmental and human disturbance variables on tree diversity and community composition was analyzed with general linear models and multivariate analyses,*** registered 2,949 individual trees belonging to 176 species and *** average species richness and alpha diversity per plot were 13(standard deviation±6)and 9(±5),*** tree richness and alpha diversity increased in the middle part(unimodal patterns)of the elevational gradient,but pioneer species richness decreased linearly with *** variance explained by general linear models was greater in richness(32%)than in alpha diversity(25.3%).The most important predictor variables were temperature(elevational gradient),which explained the unimodal pattern(richness and alpha diversity increase at intermediate levels of temperature),and slope orientation,which explained the increase in richness and alpha diversity toward the geographic *** temperature had a signific

关键词： Composition Environmental gradient Tree diversity patterns Tropical humid cloud forest Tropical volcanoes

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Synchronized bioluminescence behavior of a set of fireflies involving fractional operators of Liouville-Caputo type

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International Journal of Biomathematics 2018年第3期11卷 221-245页

作者： J. E. Escalante-Martínez J. F. Gómez-Aguilar C. Calderón-Ramón A. Aguilar-meléndez P. Padilla-Longoria Facultad de Ingenierla Mecdnica y eldctrica Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolución C.P. 93390 Poza Rica Veracruz Mdéxico CONACyT- Tecnoldgico Nacional de México/CENIDET Interior Internado Palmira S/N Col. Palmira C.P. 62490 Cuernavaca Morelos México Facultad de Ingeniería Mecdnica y eléctrica Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolución C.P. 93390 Poza Rica Veracruz México Facultad de Ingeniera Civil Universidad Veracruzana Av. Venustiano Carranza S/N Col. Revolución C.P. 93390 Poza Rica Veracruz México Instituto de Investigaciones en Matemdticas Aplicadas y Sistemas (IIMAS) UNAM Circuito Escolar Cd. Universitaria Del. Coyoacan México D.F. C.P. 04510 México

In this paper, a system of fractional differential equations that model the synchronized bioluminescence behavior of a set of fireflies put on two spatial arrangements is presented; the alternative representation of these equations contains fractional operators of IAouvillc-Caputo type. The objective of the model is to qualitatively recover synchronization and show that it is persistent. It is shown that the effort made by each firefly glow changes with respect to the number of male competitors and the distance between them. The conditions on biological parameters are interpreted.

关键词： Fractional calculus Liouville Caputo fractional derivative synchronicity fireflies bioluminescence Adams Bashforth-Moulton method.

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One-pot hydrothermal preparation of hierarchical manganese oxide nanorods for high-performance symmetric supercapacitors

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Journal of Energy Chemistry 2022年第2期31卷 116-126页

作者： Bidhan Pandit Emad S.Goda Mahmoud H.Abu elella Aafaq ur Rehman Sang Eun Hong Sachin R.Rondiya Pranay Barkataki Shoyebmohamad F.Shaikh Abdullah M.Al-Enizi Salah mel-Bahy Kuk Ro Yoon Department of Materials Science and Engineering and Chemical Engineering Universidad Carlos III de MadridAvenida de la Universidad 3028911 LeganésMadridSpain Organic Nanomaterials Lab Department of ChemistryHannam UniversityDaejeon 34054Republic of Korea Fire Protection Laboratory National Institute of Standards136Giza 12211Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Graduate School of Energy Science and Technology Chungnam National University99 Daehak-roYuseong-guDaejeon 34134Republic of Korea School of Chemistry Cardiff UniversityMain BuildingPark PlaceCardiffCF103AT WalesUnited Kingdom Department of Physics Visvesvaraya National Institute of TechnologySouth Ambazari RoadNagpur-440010MaharashtraIndia Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

An eco-friendly,new,and controllable approach for the preparation of manganese oxide(a-MnO_(2))nanorods has been introduced using hydrothermal reaction for supercapacitor *** in-depth crystal structure analysis ofα-MnO_(2) is analyzed by X-ray Rietveld refinement by using Full Prof program with the help of pseudo-Voigt profile *** developed a-MnO_(2) electrode attains a remarkable capacitance of 577.7 F/g recorded at a current density value of 1 A/g with an excellent cycle life when is used for 10,000 repeated cycles due to the porous nanorod-morphology assisting the ease penetration of electrolyte ions into the electroactive *** diffusive and capacitive contributions of the electrode have been estimated by considering standard numerical packages in *** successfully assembling the aqueous symmetric supercapacitor(SSC)cell by utilizing the as-preparedα-MnO_(2),an excellent capacitance of 163.5 F/g and energy density of 58.1 Wh/kg at the constant current density of 0.5 A/g are obtained with an expanded potential frame of 1.6 ***,the cell has exceptionally withstood up to 10,000 cycles with an ultimate capacitance retention of 94.1%including the ability to light an LED for 18 *** findings recommend the developed a-MnO_(2) electrode to be a highly felicitous electrode for the field of energy storage.

关键词： α-MnO_(2)nanorods Rietveld refinement Symmetrical supercapacitors High energy density

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Blind Modulation Recognition in Wireless MC-CDMA Systems Using a Support Vector Machine Classifier

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Wireless Engineering and Technology 2013年第3期4卷 145-153页

作者： Mohamed el-Hady Magdy Keshk Keshk el-Sayed elrabie Fathi el-Sayed Abd el-Samie Mohammed Abd el-Naby Egyptian Space Program National Authority for Remote Sensing and Space Science Cairo Egypt Faculty of electronic Engineering Menoufia University Menouf Egypt.

Automatic Digital Modulation Recognition (ADMR) is becoming an interesting problem with various civil and military applications. In this paper, an ADMR algorithm in Multi-Carrier Code Division Multiple Access (MC-CDMA) systems using Discrete Transforms (DTs) and mel-Frequency Cepstral Coefficients (MFCCs) is proposed. This algorithm uses various DT techniques such as the Discrete Wavelet Transform (DWT), Discrete Cosine Transform (DCT) and Discrete Sine Transform (DST) with MFCCs to extract features from the modulated signal and a Support Vector Machine (SVM) to classify the modulation orders. The proposed algorithm avoids over fitting and local optimal problems that appear in Artificial Neural Networks (ANNs). Simulation results shows the classifier is capable of recognizing the modulation scheme with high accuracy up to 90% - 100% using DWT, DCT and DST for some modulation schemes over a wide Signal-to-Noise Ratio (SNR) range in the presence of Additive White Gaussian Noise (AWGN) and Rayleigh fading channel, particularly at a low Signal-to-Noise ratios (SNRs).

关键词： ADMR MC-CDMA MFCC DT SVM ANN

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Stand-Alone Intelligent Voice Recognition System

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Journal of Signal and Information Processing 2014年第4期5卷 179-190页

作者： Mohammed R. Saady Hatem el-Borey el-Sayed A. el-Dahshan Ashraf Shamseldin Yahia Basic Science Department Faculty of Computers and Information Fayoum University El Fayoum Egypt Physics Department Faculty of Science Ain Shames University Cairo Egypt Egyptian E-Learning University Elmesaha El-Doki Giza Egypt

In this paper, an expert system for security based on biometric human features that can be obtained without any contact with the registering sensor is presented. These features are extracted from human’s voice, so the system is called Voice Recognition System (VRS). The proposed system?consists of a combination of three stages: signal pre-processing, features extraction by using?Wavelet Packet Transform (WPT) and features matching by using Artificial Neural Networks (ANNs). The features vectors are formed after two steps: firstly, decomposing the speech signal at level 7 with Daubechies 20-tap (db20), secondly, the energy corresponding to each WPT node is calculated which collected to form a features vector. One hundred twenty eight features vector for each speaker was fed to the Feed Forward Back-propagation Neural Network (FFBPNN). The data used in this paper are drawn from the English Language Speech Database for Speaker Recognition (elSDSR) database which composes of audio files for training and other files for testing. The performance of the proposed system is evaluated by using the test files. Our results showed that the rate of correct recognition of the proposed system is about 100% for training files and 95.7% for one testing file for each speaker from the elSDSR database. The proposed method showed efficiency results were better than the well-known mel Frequency Cepstral Coefficient (MFCC) and the Zak transform.

关键词： Voice Recognition Wavelet Packet Transform Feature Extraction Artificial Neural Network

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Ameliorative effects of melatonin and zinc oxide nanoparticles treatment against adverse effects of busulfan induced infertility in male albino mice

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BIOCelL 2022年第2期46卷 535-545页

作者： AMOURA M.ABOU-el-NAGA SHAKER A.MOUSA FAYEZ ALTHOBAITI EMAN FAYAD ENGY S.FAHIM Department of Zoology Faculty of ScienceMansoura UniversityMansouraEgypt The Pharmaceutical Research Institute Albany College of Pharmacy and Health SciencesRensselaerUSA Department of Biotechnology Faculty of SciencesTaif UniversityTaifSaudi Arabia

Testicular damage is one of the most hazardous effects as it’s associated with ***(Bu)is a highly toxic chemotherapeutic drug that affects *** male Swiss albino mice divided into six groups of 5 animals ***(oral 0.9%saline daily for 75 days);mel(20 mg/kg/day orally for 30 days);ZnO NPs(5 mg/kg/day *** 30 days);BU(single *** of 40 mg/kg and then left for 45 days);BU+mel(single 40 mg/kg dose of BU and left for 45 days followed by 20 mg/kg/day mel for 30 days);BU+ZnO NPs(single dose of 40 mg/kg of BU and left for 45 days,then 5 mg/kg/day ZnO NPs for 30 days).Preparation and Characterization of ZnO *** from testis prepared for ultrastructural investigations using TEM after Masson’s trichrome and toluidine blue *** induced histological and ultrastructural damage of the ***,the present results could be concluded that mel or ZnO NPs can protect the testicular tissue against ultrastructural alterations induced by BU by its antioxidant and anti-apoptotic effects.

关键词： Busulfan melatonin Zinc oxide nanoparticles Ultrastructure Testis Mice

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The Influence of Gonadectomy on Anxiolytic and Antidepressant Effects of melatonin in Male and Female Wistar Rats: A Possible Implication of Sex Hormones

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Neuroscience & Medicine 2012年第2期3卷 162-173页

作者： el Mrabet Fatima Zahra Lagbouri Ibtissam Mesfioui abdelhalim el Hessni Aboubakr Ouichou Ali Laboratory of Genetics Neuroendocrinology and Biotechnology Unit of Nervous and Endocrine Physiology Department of Biology Faculty of Sciences University Ibn Tofail Kenitra Morocco

The main objective of this study was to analyze the effects of sex, ovariectomy (Ovx) and orchidectomy (Orx) on antidepressant and anxiolytic effect of melatonin in forced swimming test, open field test and elevated plus maze test. Initially, 4 mg/kg of melatonin was daily administered, at 4:00 pm, to intact male and female rats during 8 weeks. Our results have shown that the effect of chronic injection of mel is sex dependent in the three behaviors tests. Females rats have responded better than males in behavior test study after administration of melatonin, this difference between the sexes may be related to the action of sex hormones (androgens and estrogens) on behavior in males as well as in females. Secondly, to determine the possible interaction between melatonin and steroid hormones, Ovx/sham female received mel at dose of 4mg/kg alone or NaCl (0.9%) alone, and Orx/sham male received mel at dose of 4 mg/kg alone or NaCl (0.9%) alone daily and during 8 weeks of treatment at 4:00 pm. All animals were tested in the open-field test, elevated plus maze test for anxiety behavior study, and forced swimming test for depression behavior study. Results revealed that mel exerts an anxiolytic and antidepressant effects in the orchidectomized males and in intact females, confirming that the suppression of androgens by orchidectomy improved anxiolytic and antidepressant effects of melatonin in males. However in females, the suppression of estrogen by ovariectomy masked the antidepressant and anxiolytic effects of melatonin. Our results confirmed that the antidepressant and anxiolytic effects of melatonin are linked to sex hormones.

关键词： melatonin Sex Dependent Anxiety Depression Behavior Tests Ovariectomy Orchidectomy Sex Hormones

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Pinealectomy and Exogenous melatonin Regulate Anxiety-Like and Depressive-Like Behaviors in Male and Female Wistar Rats

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Neuroscience & Medicine 2012年第4期3卷 394-403页

作者： el Mrabet Fatima Zahra Ouaaki Siham Mesfioui abdelhalim el Hessni Aboubakr Ouichou Ali Laboratory of Genetics Neuroendocrinology and Biotechnology Unit of Nervous and Endocrine Physiology Department of Biology Faculty of Sciences University Ibn Tofail Kenitra Morocco

The main objective of this work was to 1) study the influence of endogenous melatonin (mel) abolishment via pinealectomy and 2) explore exogenous mel effect on anxiety-like and depressive-like behavior in male and female rats. Rats were shamoperated (Sh) or pinealectomized (Px) and following subgroups were selected 1) Px/NaCl (0.9%) and Sh/NaCl (0.9%) : rats injected subcutaneously, once daily for 8 weeks, with saline solution NaCl (0.9%) as vehicle;2) Px/mel (4 mg/Kg) and Sh/mel (4 mg/Kg): Rats similarly injected with 4 mg/Kg of mel. All animals were housed under a photoperiod of (LD:16/8). After different treatments animals were tested in the open-field test (OFT), elevated plus maze test (EPM) to determine anxiety-like behavior, and forced swimming test (FST) to evaluate depressive-like level. Our results revealed that level of anxiety-like and depressive-like behavior are significantly higher in Px/NaCl (0.9%) when compared to Sh/NaCl (0.9%) group, suggesting that pinelectomy induced an anxiogenic and depressant effects. The Px effects would be due to the absence of endogenous mel synthesis and release. Additionally, we clearly demonstrated that the level of anxiety-like and depressive-like behavior are higher in Px/mel (4 mg/Kg) and Sh/mel when compared respectively to Px/NaCl (4 mg/Kg) and Sh/NaCl groups suggesting an anxiolytic and antidepressant effects of exogenous mel. Behavioral responses were sex dependent since the difference between females and males, especially, after melatonin administration, were statistically significant. These experiments provide evidence that pinealectomy and mel regulated emotionally behavior in male and female rats.

关键词： Pinealectomy melatonin Sex Dependent Anxiety Depression Behavioral Tests

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Grain Size Analysis and Wave Modeling on the Coastal Fringe of Larache （Ras R＇mel Beach）, North West of Morocco

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Journal of Shipping and Ocean Engineering 2012年第4期2卷 244-248页

作者： Nadia el Mekadem Brahim EI Moutchoul Ana M. Bemabeu Khalil el Hajjaji Department of Geology Faculty of Sciences University of Abdelmalek Essaadi Tetouan 93000 Morocco Department of Marine Geosciences Faculty of Marine Sciences University of Vigo Vigo E36310 Spain

The studied area is located in the northwestern Morocco. It occupies a 2.5 km long of coastline on the Atlantic shore. It is oriented NNE-SSW, clearly exposed to the dominant swells coming from west to northwest. The aim of this study is to determine the capacity of the waves that hit the shore to transport the sediments. To achieve our goal we chose a methodology that combines field sampling and laboratory analysis with digital modeling. In the first phase we sampled sediments from the study area along and across the beach line, dry sieving was used to determine the grain size distribution and the statistics derived from the sand samples were used to determine the critical shield stress （z＇cr, b） also to investigate the spatial variability and influence of transport on grain size characteristics. As for the second phase, we intended to create a wave climate modeling based on nautical chart, using ArcGIS then Matlab that allowed us to obtain the Swan model for the area. The correlation between those results showed the degree of contribution of wave in the distribution of sediments along the shore.

关键词： Grain size sedimentary distribution wave modeling Atlantic coast.

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Conversion of L-Tryptophan into melatonin Is the Possible Action Pathway Involved in the Effect of L-Tryptophan on Antidepressant-Related Behavior in Female Rats: Analysis of the Influence of Treatment Duration

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Journal of Behavioral and Brain Science 2013年第4期3卷 362-372页

作者： Sihame Ouakki Fatima Zahra el Mrabet Aboubaker el Hessni abdelhalem Mesfioui Paul Pévet Ali Ouichou Institute for Cellular and Integrative Neurosciences Strasbourg University Strasbourg France Laboratory of Genetics Neuroendocrinology and Biotechnology Unit of Nervous and Endocrine Physiology Faculty of Sciences Université Ibn Tofail Kenitra Morocco

The aim of this study was to determine the effect of pharmacological doses of melatonin (mel) and L-tryptophan (L-TRP) on depression-like behavior in female rats submitted to the forced swimming test (FST) after 2, 4, 6 or 8 weeks of treatment. This will allow exploring the different mechanisms of L-TRP actions particularly that due to its conversion into mel. For this purpose, four groups of 24 rats each were constituted;(Group 1: Control): received saline solution NaCl (0.9%), (Group 2: mel4): received 4 mg/Kg of mel, (Group 3: L-TRP4): received 4 mg/Kg of L-TRP and (Group 4: L-TRP20): received 20 mg/Kg of L-TRP. Animals of each group were distributed on 4 subgroups of 6 rats submitted to different time treatments. The duration of immobility (TIM) and struggling period (TST) of rats in FST were measured after 2, 4, 6 and 8 weeks of drug treatment and the effects of mel and L-TRP were compared. Chronical administration of different doses of mel or L-TRP failed to induce any anti-depressant activity in rats subjected to FST after 2 weeks of treatment. However, after 4 weeks, daily administration of mel at 4 mg/Kg significantly reduced the immobility period and enhanced struggling time. After 6 weeks, mel at 4 mg/Kg and L-TRP at 20 mg/Kg were both effective in reducing immobility and increasing struggling movement, their effects being statistically comparable. All treatments were able to significantly reduce immobility time and increase struggling duration after 8 weeks, but L-TRP at 4 mg/Kg was less potent than mel and L-TRP at 20 g/Kg. The antidepressant-like activity of L-TRP was dose and time dependent, and that of mel was time dependent. In conclusion, the study showed that at pharmacological doses, mel and L-TRP have anti-depressant action, and such effect is dependent on time treatment;mel?is more effective than L-TRP. In conclusion, L-TRP, through mel, 5-HT or by itself could modulate aminergic neurotransmission in the different brain areas to ensure its beha

关键词： melatonin L-Tryptophan Depression Forced Swimming Immobility Struggling Female Rats

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