scholarly journals Molluscs of the Genus Glycymeris from Vogelherd Cave near Niederstotzingen (Lonetal, Southwestern Germany)

2021 ◽  
Vol 29 ◽  
Author(s):  
Benjamin Schuerch ◽  
Sibylle Wolf ◽  
Patrick Schmidt ◽  
Nicholas J. Conard
Keyword(s):  
Electron Microscope ◽  
Upper Paleolithic ◽  
Long Distance ◽  
Southern Germany ◽  
Mainz Basin ◽  
Time Period ◽  
Raster Electron Microscope ◽  
Wide Range ◽  
Lithic Artifacts ◽  
Best Fit

The site of Vogelherd in the Lone Valley of southwestern Germany has become world famous for its many unique artworks made from mammoth ivory, personal ornaments, flute fragments, lithic artifacts, and antler and bone artifacts. In the study below, the molluscs from Vogelherd are presented, offering us new insights on the mobility and social behavior of Aurignacian groups in the Lone Valley. Some of the mollusc finds come from the 1931 excavation of Gustav Riek; however, most of them were uncovered during the later re-excavations of the site between 2005 and 2012. In order to provide context for these finds, we compare the molluscs from Vogelherd with those from across Central Europe. The identifiable fragments from Vogelherd belong to the genus Glycymeris. The Glycymeris molluscs originated from the Mainz Basin. This determination makes it possible to reconstruct one of the farthest long-distance connections known for the Upper Paleolithic in Germany. In addition to the Glycymeris finds, we present a tool that was also made from a mollusc. This mollusc-tool, coming from the excavation of 1931 and attributed to the Aurignacian, is a unique find for this time period of southern Germany. With this piece, along with microscopic examinations and discussions of the Glycymeris molluscs, we present a wide range of possible uses for these finds. For example, we discuss the possible use of the molluscs as ochre containers. To test this, we used EDX-analysis and a raster electron microscope. We compare the Glycymeris molluscs of Vogelherd with those from Gravettian and Magdalenian contexts at Hohle Fels, Geißenklösterle, Petersfels, and Gnirshöhle, and we provide a list of all sites from Germany, Switzerland, Eastern France, and Belgium with Glycymeris finds. We use size comparisons to show differences as well among the Glycymeris finds of Vogelherd and other Upper Paleolithic sites in southwestern Germany. In conclusion, we demonstrate that the Glycymeris molluscs of Vogelherd best fit into the Aurignacian, and we provide other Aurignacian sites that contained similar finds. By discussing other long-distance connections in the Aurignacian of southern Germany, it becomes evident that Glycymeris molluscs are not specific only to the Swabian Aurignacian.

In-situ electrical-resistivity measurements in the high-voltage electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 68-69
Author(s):  
W. E. King
Keyword(s):  
Electrical Resistivity ◽  
Electron Microscope ◽  
High Voltage ◽  
Resistivity Measurements ◽  
Voltage Electron ◽  
High Voltage Electron Microscope ◽  
High Voltage Electron ◽  
Wide Range ◽  
Helium Gas

A side-entry type, helium-temperature specimen stage that has the capability of in-situ electrical-resistivity measurements has been designed and developed for use in the AEI-EM7 1200-kV electron microscope at Argonne National Laboratory. The electrical-resistivity measurements complement the high-voltage electron microscope (HVEM) to yield a unique opportunity to investigate defect production in metals by electron irradiation over a wide range of defect concentrations.A flow cryostat that uses helium gas as a coolant is employed to attain and maintain any specified temperature between 10 and 300 K. The helium gas coolant eliminates the vibrations that arise from boiling liquid helium and the temperature instabilities due to alternating heat-transfer mechanisms in the two-phase temperature regime (4.215 K). Figure 1 shows a schematic view of the liquid/gaseous helium transfer system. A liquid-gas mixture can be used for fast cooldown. The cold tip of the transfer tube is inserted coincident with the tilt axis of the specimen stage, and the end of the coolant flow tube is positioned without contact within the heat exchanger of the copper specimen block (Fig. 2).

scholarly journals CONSTRAINTS EXPERIENCED BY MUSHROOM GROWERS IN ADOPTING IMPROVED MUSHROOM PRODUCTION PRACTICES IN PUSA, BIHAR

2021 ◽  
Vol 8 (7) ◽  
pp. 97-106
Author(s):  
Saloni Sarraf ◽  
Dipak Kumar Bose ◽  
Jahanara Jahanara ◽  
Amit Kumar
Keyword(s):  
Transport Cost ◽  
Primary Data ◽  
Mushroom Cultivation ◽  
Short Time Period ◽  
Long Distance ◽  
Mushroom Production ◽  
Time Period ◽  
Production Practices ◽  
Short Time ◽  
Technical Guidance

Mushrooms (vegetarian meat/vegetable beef stick) is becoming fast popular because of its short time period between cultivation and harvesting; less initial investment and can be grown with locally available resources. Though more technology is available for boosting mushroom production, the yield so far achieved is not high. Hence, an attempt is made to find out the constraints faced by mushroom growers in adoption of improved mushroom production practices. Samastipur district of Bihar was purposively selected for the study because, Dr. Rajendra Prasad Central Agricultural University, a pioneer in mushroom production technology is located in the study area. 120 respondents from six villages of Pusa, Samastipur, Bihar forms the respondents of the present study. Primary data was collected from the mushroom growers and the responses were subjected to statistical analysis. The results indicated that unavailability of quality spawn, unavailability of skilled labor, absence of technical guidance, high transport cost, unavailability of storage facilities, high cost of spawn and long distance market were the most problematic constraints faced by the mushroom growers. Thus, it can be concluded that adequate extension service should be made available to make mushroom cultivation popular, market and marketing of the products.

scholarly journals FEI Titan 80-300 TEM

2016 ◽  
Vol 2 ◽  
Author(s):  
Andreas Thust ◽  
Juri Barthel ◽  
Karsten Tillmann
Keyword(s):  
Electron Microscope ◽  
Solid State ◽  
Spherical Aberration ◽  
Atomic Scale ◽  
Atomic Resolution ◽  
Lens System ◽  
Stage Design ◽  
Precise Positioning ◽  
Transmission Electron ◽  
Wide Range

The FEI Titan 80-300 TEM is a high-resolution transmission electron microscope equipped with a field emission gun and a corrector for the spherical aberration (<em>C</em><sub>S</sub>) of the imaging lens system. The instrument is designed for the investigation of a wide range of solid state phenomena taking place on the atomic scale, which requires true atomic resolution capabilities. Under optimum optical settings of the image <em>C</em><sub>S</sub>-corrector (CEOS CETCOR) the point-resolution is extended up to the information limit of well below 100 pm with 200 keV and 300 keV electrons. A special piezo-stage design allows ultra-precise positioning of the specimen in all 3 dimensions. Digital images are acquired with a Gatan 2k x 2k slow-scan charged coupled device camera.

The influence of floral morph ratios and low plant density on mating and fertility in a tristylous colonizing species

Botany ◽  
2018 ◽  
Vol 96 (8) ◽  
pp. 533-545 ◽  
Author(s):  
Christopher M. Balogh ◽  
Spencer C.H. Barrett
Keyword(s):  
Field Experiment ◽  
Seed Set ◽  
Plant Density ◽  
Pollen Limitation ◽  
Lythrum Salicaria ◽  
Long Distance ◽  
Experimental Conditions ◽  
Wide Range ◽  
Morph Ratios ◽  
Floral Morph

Sexual reproduction in heterostylous populations may be vulnerable to demographic conditions because of the small number of mating types in populations. Here, we investigate mating and fertility under natural and experimental conditions in tristylous Lythrum salicaria L., an invasive species that exhibits a wide range of floral morph ratios and demographic contexts. We grew 147 open-pollinated seed families from six populations with different morph structures to estimate intermorph mating (d). In a field experiment, we used progeny ratios from 47 spatially isolated individuals to estimate d, and measured the intensity of pollen limitation experienced by the morphs. The M- and S-morphs experienced high rates of d, regardless of population size or morph ratio. Estimates for the L-morph revealed low levels of intramorph mating in three dimorphic and two trimorphic populations, but near complete intramorph mating in a monomorphic population. Despite high levels of intermorph mating in the field experiment, the morphs experienced significant pollen limitation of fruit and seed set, but this did not differ in intensity among the morphs. Our field experiment demonstrates that although plant isolation was associated with pollen limitation of seed set, “long-distance” bee-mediated pollen flow served to maintain intermorph mating. Tristyly in L. salicaria is remarkably robust to the demographic variation associated with colonization.

Changes in the properties of the developing trophoblast of preimplantation mouse embryos as revealed by aggregation studies

Development ◽  
1977 ◽  
Vol 40 (1) ◽  
pp. 143-157
Author(s):  
Paul S. Burgoyne ◽  
Thomas Ducibella
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Supporting Cell ◽  
Mouse Embryos ◽  
Mixed Cell ◽  
Time Period ◽  
Preimplantation Mouse Embryos ◽  
Wide Range ◽  
Preimplantation Mouse

Mouse embryos (8-cell to early blastocyst) were denuded with pronase, and apposed in pairs which represented a wide range of stage combinations. These pairs either formed aggregates which differentiated into double-sized blastocysts, or they failed to aggregate. The 8–16-cell stages would not envelop late morulae/early blastocysts to form layered aggregates. This must mean that as the embryo differentiates into a blastocyst, the outer surface of the trophoblast loses its capacity for supporting cell spreading. The aggregation data also demonstrate that embryos almost completely lose their potential for aggregation at a very discrete stage in development – namely, between 8 and 9 h before blastocoel formation. It is argued that this is the stage at which the zonular tight junctional seal is completed, and that it is this physical barrier which prevents aggregation. It has been argued previously that the zonular tight junctional seal allows the creation of the special microenvironment which is necessary for the determination of the inner cells as inner cell mass. The completion of this seal 8–9 h before it is required for the formation of a blastocoel would provide a suitable time period for this cell determination to occur. The results obtained also relate to the technique of chimera production. Since the aim of this technique is to generate mice with mixed cell populations, it is important that the blastocyst formed following aggregation should have both cell lines present in the inner cell mass. This can best be assured by using relatively late morula stages (75 h post-HCG injection) since these will have already segregated their inner cells, but the incomplete seal will still allow aggregation to take place.

Chlorophyll-a Concentration Assessment Using Remotely Sensed Data over Multiple Years along the Coasts of the United Arab Emirates

2020 ◽  
pp. 345
Author(s):  
Eihab M. Fathelrahman ◽  
Khalid A. Hussein ◽  
Safwan Paramban ◽  
Timothy R. Green ◽  
Bruce C. Vandenberg
Keyword(s):  
Chlorophyll A ◽  
United Arab Emirates ◽  
Algal Blooms ◽  
Water Desalination ◽  
Least Square ◽  
Sufficient Information ◽  
Chlorophyll A Concentration ◽  
Explanatory Variables ◽  
Wide Range ◽  
Best Fit

The United Arab Emirates (UAE) recently witnessed algal/phytoplankton blooms attributed to the high concentrations of Chlorophyll-a associated with the spread and accumulation of a wide range of organisms with toxic effects that influence ecological and fishing economic activities and water desalination along coastal areas.  This research explores the UAE coasts as a case study for the framework presented here. In this research, we argue that advances in satellite remote sensing and imaging of spatial and temporal data offer sufficient information to find the best-fit regression method and relationship between Chlorophyll-a concentration and a set of climatic and biological explanatory variables over time. Three functional forms of regression models were tested and analysed to reveal that the Log-Linear Model found to be the best fit providing the most statistically robust model compared to the Linear and the Generalised Least Square models.  Besides, it is useful to identify the factors Sea Surface temperature, Calcite Concentration, Instantaneous Photosynthetically Available Radiation, Normalized Fluorescence Line Height, and Wind Speed that significantly influence Chlorophyll-a concentration. Research results can be beneficial to aid decision-makers in building a best-fit statistical system and models of algal blooms in the study area. The study found results to be sensitive to the study’s temporal time-period length and the explanatory variables selected for the analysis.

The Top 50 Most Cited Publications in Meniscus Research

2021 ◽  
Author(s):  
Kyle N. Kunze ◽  
Aidan Haddad ◽  
Alexander E. White ◽  
Matthew R. Cohn ◽  
Robert F. LaPrade ◽  
...  
Keyword(s):  
Sports Medicine ◽  
Citation Rate ◽  
Cross Sectional Study ◽  
Collective Knowledge ◽  
Cross Sectional ◽  
Anterior Cruciate Ligaments ◽  
Time Period ◽  
Wide Range ◽  
Anterior Cruciate

AbstractInjuries to the menisci of the knee are common in orthopedic sports medicine. Bibliometric studies can identify the core literature on a topic and help further our collective knowledge for both clinical and educational purposes. The purpose of the current study was to (1) identify and describe the 50 most cited articles in meniscus research over an 80-year time period to capture a wide range of influential articles and (2) identify the “citation classics” and milestone articles related to the meniscus of the knee. The Science Citation Index Expanded subsection of the Web of Science Core Collection was systematically searched for the 50 most cited meniscus articles. Data pertaining to bibliometric and publication characteristics were extracted and reported using descriptive statistics. The top 50 articles were published between the years 1941 and 2014 and collectively cited 13,152 times. The median (interquartile [IQR]) number of total citations per article was 203.5 (167.0–261.8), while the median citation rate was 9.6 (7.4–13.9) citations per year. The most cited article was “Knee joint changes after meniscectomy,” published in 1948. The article with the highest citation rate of 78.4 citations per year was “The long-term consequence of anterior cruciate ligaments and meniscus injuries – osteoarthritis,” published in 2007. The majority of articles were clinical outcome studies (n = 28, 56%). The top 50 most cited meniscus articles represent a compilation of highly influential articles which may augment reading curriculums and provide a strong knowledge base for orthopaedic surgery residents and fellows. The decade with the most articles was the 2000s, representing a recent acceleration in meniscus-based research. This is a level IV, cross-sectional study.

A Periodical of Their Own: Feminist Writing in Religious Print Media

2018 ◽  
Author(s):  
Jacqueline R. deVries
Keyword(s):  
Interwar Period ◽  
Print Media ◽  
Leadership Roles ◽  
Religious Traditions ◽  
Religious Media ◽  
Time Period ◽  
Wide Range ◽  
Institutional Structures ◽  
Feminist Writing ◽  
And Gender

In this volume’s rich survey of women’s print media in the interwar period, it might be surprising to find a chapter on feminist writing in religious periodicals – that is, if one assumes that Britain’s religious traditions were inhospitable contexts for feminist organising during this time period. But that assumption would not be entirely correct. The Anglican, Catholic, and Jewish communities in Britain – the three traditions explored here – certainly clung to theological and institutional structures that prevented women from moving freely or quickly into leadership roles. But these communities were never homogenous and their members expressed a wide range of attitudes about gender, sexuality, and women’s roles, some of which were highly progressive and found their way into print. The changing social and gender norms of the interwar period were much debated topics in Britain’s religious communities, and through their engagement with religious media, women found ways to influence those debates.

Assessing the Paleobiology of the Sunghir People

2014 ◽  
Author(s):  
Erik Trinkaus ◽  
Alexandra P. Buzhilova ◽  
Maria B. Mednikova ◽  
Maria V. Dobrovolskaya
Keyword(s):  
Western Europe ◽  
Human Remains ◽  
Human Existence ◽  
Upper Paleolithic ◽  
The People ◽  
Time Period ◽  
Human Burials ◽  
Human Foraging ◽  
The 19Th Century ◽  
Work Done

During the Mid Upper Paleolithic, the period of Late Pleistocene human existence within the Interpleniglacial, human foraging populations developed an increasingly sophisticated, elaborated, and complicated existence across Eurasia and probably across most of the Old World. This period of the Paleolithic saw the emergence of various forms of elaborate technology (e.g., ceramics and textiles, as well as elaborations of lithic and organic tool manufacture and use), expanded artistic manifestations, complex social behaviors (especially reflected in personal decoration and mortuary behavior), and increasingly effective and flexible means of subsistence and food processing. For these reasons, the people of this period were referred to, a dozen years ago, as the “Hunters of the Golden Age” (Roebroeks et al. 2000). In those and other assessments of these people, referred to as “Gravettian” in central and western Europe and by other names further east, there is frequent reference to the material from the northern Russian site of Sunghir (Сунгирь; Sungir’). The references to Sunghir are especially to the extremely rich human burials discovered during excavations in 1964 and 1969. The human paleontological materials from Sunghir, however, have only been superficially integrated into the broader assessments of human existence during this time period of hunter-gatherer fluorescence. Several volumes (and innumerable articles) have been written on aspects of the archeological work done at the Sunghir site (e.g., Sukachev et al. 1966; O.N. Bader 1978; N.O. Bader 1998; Seleznev 2008), and there have been two edited volumes concerned principally with the human remains from within and without the burials (Zubov and Karitonov 1984; Alexeeva et al. 2000). However, all of these volumes (as is appropriate) are in Russian, and only the last of them contains extensive English summaries of the contributions. As a result (given the linguistically challenged nature of many Western anthropologists—including one of us), detailed assessments of the Sunghir site and the Sunghir human remains have been slow to permeate the broader anthropological community. Originally, in the 19th century and through much of the 20th century, the focus was on the populational affinities of human remains that emerged from the Upper Paleolithic of Eurasia.

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