scholarly journals The Reserva de la Biosfera Barranca de Metztitlán (Hidalgo): An illustrated checklist of bromeliads and orchids and their high levels of Mexican endemisms

PhytoKeys ◽  
2019 ◽  
Vol 118 ◽  
pp. 105-123
Author(s):  
Claudia T. Hornung-Leoni ◽  
Yesenia J. Chavarria-Olmedo ◽  
Ivón M. Ramírez-Morillo
Keyword(s):  
Relative Abundance ◽  
New Records ◽  
Ex Situ ◽  
Risk Category ◽  
Herbarium Specimens ◽  
Natural Area ◽  
Mexican State ◽  
Different Types ◽  
Conservation Plan

This study presents a list of species of the two most important families with epiphytic elements, Bromeliaceae and Orchidaceae, from the Reserva de la Biosfera Barranca de Metztitlán (RBBM), the largest Reserve in Hidalgo, Mexico. Thirty-four species are included, 26 corresponding to species in three genera of bromeliads, and eight species in six genera of orchids. The new records represent 26.5% of the total listed in the area; nine of them are new records for the Reserve (RBBM) and one is new for Hidalgo State. This study reveals that endemism for both families is very important in the Reserve (55.88%), since it includes 13 Mexican bromeliads, of which two are endemic to Hidalgo and one to the Reserve, and three orchids, two endemic to Mexico and one to the Reserve. We found species with different types of relative abundance: rare (16) and occasional (7). Additionally, we include information about the category (IUCN, CITES, NOM-059-SEMARNAT) as well as uses reported in the literature for the species in the RBBM. The checklist is strictly based on information obtained from deposited herbarium specimens as well as from those collected during fieldwork. We suggest that a conservation plan (in situ and ex situ) for the RBBM is important and necessary. The predominant habit for both families is epiphytic (17 species); even though there are terrestrial (7) and saxicolous (2), and the remaining are facultative species (8). Nine species are included in some risk category. The present work is the most complete and updated list of Bromeliaceae and Orchidaceae for this important natural area in the Mexican State of Hidalgo. However, more fieldwork is needed to document the biodiversity of the area in general and its flora in particular, as a way to highlight the importance of protected areas in preserving biodiversity.

scholarly journals The Role of Gardens in Integrated Conservation Practice

2019 ◽  
pp. 177-188
Author(s):  
Audrey Denvir ◽  
Jeannine Cavender-Bares ◽  
Antonio González-Rodríguez
Keyword(s):  
Plant Conservation ◽  
Ex Situ ◽  
Conservation Practice ◽  
Integrated Research ◽  
Academic Researchers ◽  
Conservation Plan ◽  
Species Specific ◽  
Integrated Conservation

Gardens and horticulturists play an increasingly important role in plant conservation, both in situ and ex situ. Integrated research and conservation of species intends to work across fields to connect science to conservation practice by engaging actors from different sectors, including gardens. The case of integrated conservation of Quercus brandegeei, a microendemic oak species in Baja California Sur, Mexico, is presented as an example of a collaboration between gardens and academic researchers to create a species-specific conservation plan that incorporates horticultural knowledge.

scholarly journals Heavy metal phytoremediation: Potential and advancement

2020 ◽  
pp. 81-93
Author(s):  
Pushpa Chaudhary Tomar ◽  
Shilpa Samir Chapadgaonkar ◽  
Varsha Panchal ◽  
Arpita Ghosh
Keyword(s):  
Heavy Metal ◽  
Industrial Waste ◽  
Research Work ◽  
Industrial Effluents ◽  
Ex Situ ◽  
Plant Tissues ◽  
Land Resource ◽  
Environmental Friendly ◽  
Different Types

Industrial activities lead to the release of different types of toxic metals into the environment. Phytoremediation has been established as one of the environmental-friendly and economical processes that have the potential for the remediation of industrial waste. Phytoremediation is used to extract metals from industrial effluents using ex-situ and in-situ treatments. Also, phytoremediation may be used to reclaim the polluted land resource for agricultural purposes. Moreover, this also prevents the bioaccumulation and biomagnification of xenobiotics from farming activities if carried out from polluted land. Phyto-mining can be done to recover and reuse the heavy metals from plant tissues after phytoremediation by plants. This study aimed to give a comprehensive review of recent research work in heavy metal phytoremediation.

scholarly journals Structural Vulnerability Assessment of Heritage Timber Buildings: A Methodological Proposal

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 881
Author(s):  
Amirhosein Shabani ◽  
Mahdi Kioumarsi ◽  
Vagelis Plevris ◽  
Haris Stamatopoulos
Keyword(s):  
Construction Material ◽  
Ex Situ ◽  
Structural Vulnerability ◽  
Environmental Threats ◽  
Construction Techniques ◽  
Vulnerability Assessments ◽  
Different Types ◽  
Risk Knowledge

The conservation of heritage structures is pivotal not only due to their cultural or historical importance for nations, but also for understanding their construction techniques as a lesson that can be applied to contemporary structures. Timber is considered to be the oldest organic construction material and is more vulnerable to environmental threats than nonorganic materials such as masonry bricks. In order to assess the structural vulnerability of heritage timber structures subjected to different types of risk, knowledge about their structural systems and configurations, the nature and properties of the materials, and the behavior of the structure when subjected to different risks, is essential for analysts. In order to facilitate the procedure, different assessment methods have been divided into the categories in situ and ex situ, which are applicable for vulnerability assessments at the element and full-scale level of a case study. An existing methodology for structural vulnerability assessments and conservation of heritage timber buildings is reviewed and a new methodology is proposed.

The surface structure of GaAs(100) studied by RHEED and REM

1990 ◽  
Vol 48 (4) ◽  
pp. 626-627
Author(s):  
Tung Hsu ◽  
G.S. Petrich ◽  
P. I. Cohen
Keyword(s):  
Molecular Beam ◽  
Flux Ratio ◽  
High Energy ◽  
Ex Situ ◽  
High Energy Electron ◽  
Grown Film ◽  
Mbe Growth ◽  
Different Types ◽  
Reflection Electron Microscopy

Three GaAs( 100) samples, each grown on a differently misoriented GaAs( 100) substrate, were prepared using molecular beam epitaxy (MBE) and characterized by in situ reflection high energy electron diffraction (RHEED) and ex situ RHEED and reflection electron microscopy (REM): A: the substrate is 2° off the (100) toward [011] (A misorientation),B: the substrate is 2° off the (100) toward (B misorientation), andC: the substrate is within 0.1° of (100) (Fig. 1).The goals were to compare the effects of MBE growth and oxidation on the different types of steps formed on these surfaces. Understanding the processes involved in promoting ordering of terrace lengths, and reduction of meandering and step bunching is crucial to current attempts to fabricate quantum wire structures.Samples were prepared by chemically etching the substrates and then growing 0.2μm of GaAs at 600°C, at a rate of 0.4μm/h, and using a 3:1 As:Ga flux ratio. Shapes of the in situ RHEED spots were used to measure the step configuration while the oscillation of RHEED intensities was used to determine the thickness of the grown film.

scholarly journals Palaeogeographical heritage of the Permian Period in the network of protected areas and museums of the Perm Region

2020 ◽  
Vol 169 ◽  
pp. 02018
Author(s):  
Yuliya Glazyrina ◽  
Larisa Zhuzhgova ◽  
Sergey Buzmakov ◽  
Pavel Sannikov
Keyword(s):  
Protected Areas ◽  
Point Of View ◽  
Ex Situ ◽  
Museum Collections ◽  
Different Types ◽  
The City ◽  
Perm Region

Article presents an overview of palaeogeographical heritage of the Permian Period in the network of protected areas and museums of the Perm Region. Permian Period, received its name after the city of Perm in Russia, includes the so-called “Main Permian Field”. It contains two types of palaeogeorgaphical heritage: marine and terrestrial. The representation of palaeogeographical objects of different types is analysed for the geoheritage of the protected areas in situ. Geoheritage ex situ, in the network of the regional museum collections, is estimated from the representative aspects. Recommendations on optimization of the protected areas network and museum acquisition is given from the point of view of paleo-geographical heritage objects representation.

scholarly journals Confirmación de la distribución de Notiosorex crawfordi en Hidalgo, México.

2014 ◽  
Vol 30 (1) ◽  
Author(s):  
Shirley Lombera Nopal ◽  
Violeta Canales Almaraz ◽  
Maricela López Mejía ◽  
Génesis Mejía Vera ◽  
Jesús Castillo-Cerón
Keyword(s):  
United States Of America ◽  
New Records ◽  
The United States ◽  
Great Distance ◽  
Nuevo Leon ◽  
Northern Mexico ◽  
Nuevo León ◽  
Mexican State ◽  
Different Types ◽  
New Localities

We added four recent records from three new localities for the desert shrew Notiosorex crawfordi, in the Mexican state of Hidalgo. The distribution commonly accepted for this shrew occupies the southern part of the United States of America, and the neighboring region of Northern Mexico (Baja California Norte and Sur, Sonora, Chihuahua, Colima, Tamaulipas, Sinaloa, Durango and Zacatecas). The records confirm the existence of the species in the state and extend its distribution until the municipality of Tetepango, 31 km to SW of the Grutas de Xoxafi and through the municipality of Tulancingo de Bravo, 75.8 km SE of the Grutas de Xoxafi, and 542 km south of the southernmost records recognized in Nuevo Leon. These records come to give certainty of the existence of this species in Hidalgo, since the scarce records and the great distance to the next known accepted locality (3 km SW Galeana, Nuevo Leon). The record most resent was obtained at 2001, and the scarce records made the presence of N. crawfordi in Hidalgo seem uncertain. The new records are located in areas in which developed different types of xeric scrublands, vegetation in which inhabits this shrew commonly. The existence of Notiosorex in Hidalgo will can pass unnoticed because this shrew is considered rare and difficult to capture.

scholarly journals Phototrophs in alternative energy

2021 ◽  
Vol 11 (3) ◽  
pp. 358-371
Author(s):  
M. S. Konovalo ◽  
E. Yu. Konovalova ◽  
I. N. Egorova ◽  
G. O. Zhdanova ◽  
D. I. Stom
Keyword(s):  
Microbial Fuel Cells ◽  
Alternative Energy ◽  
Biofuel Cells ◽  
Ex Situ ◽  
Unicellular Algae ◽  
Enzymatic Biofuel Cells ◽  
Main Emphasis ◽  
Different Types

Abstract: The role of phototrophs is examined in alternative energy, with the main emphasis on unicellular algae. Particular attention is paid to the use of phototrophs for generating electricity using biofuel cells (plant and enzymatic biofuel cells are discussed). This study focuses on microbial fuel cells (MFC), which, along with electric power, allow obtaining biofuels and biohydrogen. This article explains the factors limiting the MFC power, and ways of overcoming them. For example, it seems promising to develop various photobioreactors in order to reduce the loss of MFC power due to overvoltage. The use of microphototrophs in MFC has led to the development of photosynthetic MFC (or PhotoMFC) through the design of autotrophic photobioreactors with forced illumination. They allow generating oxygen through photosynthesis, both in situ and ex situ, by recirculating oxygen from the photobioreactor to the cathode chamber. Artificial redox mediators can be used here, transferring electrons directly from the non-catalytic cathode to O2, formed as a result of the photosynthetic activity of algae. Biologically catalyzed cathodes have been proven to generate less power than chemical catalysts. It is noted, that the MFC installations with the micro-algae allow utilizing a wider circle of different connections – the components of effluents and withdrawals: organic acids, sugar, alcohols, fats and other substrata. The use of phototrophs for the production of biofuels is of special interest. Several different types of renewable biofuels can be produced from microalgae, the production of which can be combined with wastewater treatment, CO2 capture and production of various compounds.

scholarly journals Pulsed electric current sintering of TiB2-based ceramics using nitride additives

2021 ◽  
Vol 1 (1) ◽  
pp. 28-33
Author(s):  
Naeimeh Sadat Peighambardoust ◽  
Çağın Çevik ◽  
Tannaz Assar ◽  
Sunghoon Jung ◽  
Seon Yong Lee ◽  
...  
Keyword(s):  
Ex Situ ◽  
X Ray Diffraction ◽  
Si3n4 Ceramic ◽  
X Ray ◽  
Pulsed Electric Current ◽  
Different Types ◽  
Microstructural Evaluation ◽  
In Situ Formation ◽  
Field Assisted Sintering

In this research, various types of nitride additives were incorporated into titanium diboride attaining dense TiB2-based ceramics by field-assisted sintering technique. The addition of different types of nitride additives, namely Si3N4, BN, AlN, and TiN, significantly improved the sinterability of TiB2, achieving near fully dense ceramics. The X-ray diffraction analysis and microstructural evaluation confirmed the presence of the h-BN compound in all specimens. In the TiB2-Si3N4 ceramic, Si3N4 additive reacted with B2O3 oxide, in-situ generating h-BN, and SiO2 phases. Although the h-BN phase was produced in the TiB2-AlN specimen, the main proportion of AlN remained in the sample as an unreacted ex-situ phase. In terms of the TiB2-TiN ceramic, some of the nitrogen and boron atoms could leave the TiN and TiB2 crystalline structures, contributing to the in-situ formation of h-BN.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

The use of transmission and analytical electron microscopy in studying reactions and phase transformations in thin film

1993 ◽  
Vol 51 ◽  
pp. 842-843
Author(s):  
K. Barmak
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Phase Transformations ◽  
Analytical Electron Microscopy ◽  
Ex Situ ◽  
Multilayer Thin Films ◽  
Absolute Concentration ◽  
Analytical Electron ◽  
Deposition Step

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.

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