scholarly journals Biodeterioration Patterns and Their Interpretation for Potential Applications to Stone Conservation: A Hypothesis from Allelopathic Inhibitory Effects of Lichens on the Caestia Pyramid (Rome)

2020 ◽  
Vol 12 (3) ◽  
pp. 1132 ◽  
Author(s):  
Giulia Caneva ◽  
Maria Rosaria Fidanza ◽  
Chiara Tonon ◽  
Sergio Enrico Favero-Longo
Keyword(s):  
Biochemical Properties ◽  
Lichen Species ◽  
Archaeological Sites ◽  
Inhibitory Effects ◽  
Stone Conservation ◽  
Lichen Substances ◽  
Potential Applications ◽  
The Rich ◽  
Source Of Information

The colonisation of stone by different organisms often leaves biodeterioration patterns (BPs) on the surfaces even if their presence is no longer detectable. Peculiar weathering patterns on monuments and rocks, such as pitting phenomena, were recognised as a source of information on past colonisers and environmental conditions. The evident inhibition areas for new bio-patinas observed on the marble blocks of the Caestia Pyramid in Rome, recognisable as tracks of previous colonisations, seem a source for developing new natural products suitable for restoration activities. To hypothesise past occurring communities and species, which gave rise to such BPs, we carried out both in situ observations and analyses of the rich historical available iconography (mainly photographs). Moreover, we analysed literature on the lichen species colonising carbonate stones used in Roman sites. Considering morphology, biochemical properties and historical data on 90 lichen species already reported in Latium archaeological sites, we suppose lichen species belonging to the genus Circinaria (Aspicilia s.l.) to be the main aetiological agent of such peculiar BPs. These results seem relevant to highlight the long-lasting allelopathic properties of some lichen substances potentially applicable as a natural product to control colonisation, improving the environmental and economical sustainability of stone restoration.

scholarly journals Herpetological phylogeographic analyses support a Miocene focal point of Himalayan uplift and biological diversification

2020 ◽  
Author(s):  
Wei Xu ◽  
Wen-Jie Dong ◽  
Ting-Ting Fu ◽  
Wei Gao ◽  
Chen-Qi Lu ◽  
...  
Keyword(s):  
Middle Miocene ◽  
Focal Point ◽  
Himalayan Region ◽  
The World ◽  
Early Paleocene ◽  
The Rich ◽  
Source Of Information ◽  
The Himalaya ◽  
Exact Timing

Abstract The Himalaya are among the youngest and highest mountains in the world, but the exact timing of their uplift and origins of their biodiversity are still in debate. The Himalayan region is a relatively small area but with exceptional diversity and endemism. One common hypothesis to explain the rich montane diversity is uplift-driven diversification–that orogeny creates conditions favoring rapid in situ speciation of resident lineages. We test this hypothesis in the Himalayan region using amphibians and reptiles, two environmental sensitive vertebrate groups. In addition, analysis of diversification of the herpetofauna provides an independent source of information to test competing geological hypotheses of Himalayan orogenesis. We conclude that the origins of the Himalayan herpetofauna date to the early Paleocene, but that diversification of most groups was concentrated in the Miocene. There was an increase in both rates and modes of diversification during the early to middle Miocene, together with regional interchange (dispersal) between the Himalaya and adjacent regions. Our analyses support a recently proposed stepwise geological model of Himalayan uplift beginning in the Paleocene, with a subsequent rapid increase of uplifting during the Miocene, finally give rise to the intensification of the modern South Asia Monsoon.

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.

Synthesis and biochemical properties of the novel, enzymatically stable mRNA cap analogues with versatile potential applications

2005 ◽  
Author(s):  
Marcin Kalek ◽  
Jacek Jemielity ◽  
Ewa Grudzien ◽  
Joanna Zuberek ◽  
Zbigniew M. Darzynkiewicz ◽  
...  
Keyword(s):  
Biochemical Properties ◽  
The Novel ◽  
Potential Applications

scholarly journals Influence of protein (human galectin-3) design on aspects of lectin activity

2020 ◽  
Vol 154 (2) ◽  
pp. 135-153 ◽  
Author(s):  
Gabriel García Caballero ◽  
Donella Beckwith ◽  
Nadezhda V. Shilova ◽  
Adele Gabba ◽  
Tanja J. Kutzner ◽  
...  
Keyword(s):  
Protein Design ◽  
Full Range ◽  
Biological Information ◽  
The Novel ◽  
Modular Assembly ◽  
Binding Partners ◽  
Galectin 3 ◽  
Potential Applications ◽  
Similar Affinity

Abstract The concept of biomedical significance of the functional pairing between tissue lectins and their glycoconjugate counterreceptors has reached the mainstream of research on the flow of biological information. A major challenge now is to identify the principles of structure–activity relationships that underlie specificity of recognition and the ensuing post-binding processes. Toward this end, we focus on a distinct feature on the side of the lectin, i.e. its architecture to present the carbohydrate recognition domain (CRD). Working with a multifunctional human lectin, i.e. galectin-3, as model, its CRD is used in protein engineering to build variants with different modular assembly. Hereby, it becomes possible to compare activity features of the natural design, i.e. CRD attached to an N-terminal tail, with those of homo- and heterodimers and the tail-free protein. Thermodynamics of binding disaccharides proved full activity of all proteins at very similar affinity. The following glycan array testing revealed maintained preferential contact formation with N-acetyllactosamine oligomers and histo-blood group ABH epitopes irrespective of variant design. The study of carbohydrate-inhibitable binding of the test panel disclosed up to qualitative cell-type-dependent differences in sections of fixed murine epididymis and especially jejunum. By probing topological aspects of binding, the susceptibility to inhibition by a tetravalent glycocluster was markedly different for the wild-type vs the homodimeric variant proteins. The results teach the salient lesson that protein design matters: the type of CRD presentation can have a profound bearing on whether basically suited oligosaccharides, which for example tested positively in an array, will become binding partners in situ. When lectin-glycoconjugate aggregates (lattices) are formed, their structural organization will depend on this parameter. Further testing (ga)lectin variants will thus be instrumental (i) to define the full range of impact of altering protein assembly and (ii) to explain why certain types of design have been favored during the course of evolution, besides opening biomedical perspectives for potential applications of the novel galectin forms.

scholarly journals Variability and improvement of optical and antimicrobial performances for CQDs/mesoporous SiO2/Ag NPs composites via in situ synthesis

2021 ◽  
Vol 10 (1) ◽  
pp. 403-411
Author(s):  
Youliang Cheng ◽  
Mingjie Wang ◽  
Changqing Fang ◽  
Ying Wei ◽  
Jing Chen ◽  
...  
Keyword(s):  
Uv Light ◽  
Carbon Quantum Dots ◽  
Diffusion Method ◽  
Ag Nps ◽  
Uniform Size ◽  
High Antibacterial Activity ◽  
Fluorescent Materials ◽  
Potential Applications ◽  
Mesoporous Sio2

Abstract To change the optical properties and improve the antibacterial performances of carbon quantum dots (CQDs) and Ag NPs, mesoporous SiO2 spheres were combined with them to form the composites. In this paper, CQDs with a uniform size of about 3.74 nm were synthesized using glucose as carbon source. Then, CQDs/mesoporous SiO2/Ag NPs composites were obtained in situ under UV light irradiating by using mesoporous SiO2 and Ag NO3 as the carrier and silver resource, respectively. The diameter of CQDs/mesoporous SiO2/Ag NPs particles was in the range of 200–250 nm. With the increase in irradiating time, the red-shift in the UV-Vis spectrum for as-prepared CQDs/mesoporous SiO2/Ag NPs composites was found, and the adsorption peak was widened. In addition, the composites showed a high antibacterial activity against Staphylococcus aureus and Escherichia coli via disc diffusion method. These results indicated that inhibition circles for Ag NPs/mesoporous SiO2/CQDs and mesoporous SiO2/Ag NPs were similar in diameter. Furthermore, the two composites had a better bactericidal performance compared with other particles. Therefore, as-prepared CQDs/mesoporous SiO2/Ag NPs composites in this paper have great potential applications for fluorescent materials and antibacterial materials.

Beneficial Effects of Liposomal Formulations of Lichen Substances: A Review

2021 ◽  
Vol 18 ◽  
Author(s):  
Vinay Bharadwaj Tatipamula ◽  
Ha Thi Nguyen ◽  
Biljana Kukavica
Keyword(s):  
Substantial Improvement ◽  
Traditional Medicines ◽  
Beneficial Effects ◽  
Liposomal Formulations ◽  
Lichen Substances ◽  
Potential Applications ◽  
Lichen Metabolites ◽  
North And South America ◽  
North And South ◽  
Low Solubility

: Lichens are commonly used as essential traditional medicines to treat various conditions, including skin disorders, wounds, digestive, respiratory, obstetric, and gynecological problems in many cultures in Africa, Asia, Europe, Haitian, Oceania, and North and South America. Lichens have been deeply investigated for their phytochemical properties, and to date, numerous compounds (also known as substances) have been successfully isolated from the extracts. However, the low solubility and bioavailability of pure lichen substances have been widely recognized as the significant issues hindering their biological applications. Recently, several groups have investigated the properties and the potential applications of lichen metabolites-based liposomal formulations and revealed a substantial improvement in their solubility, bioactivity, and toxicity in the animal. Thus, in this topical review, we aimed to provide an overview of liposomal structures, the efficacy of liposomal formulations, as well as their beneficial effects as compared to the free compounds themselves.

scholarly journals A Leaf Point Documents Hunting with Spears in the Middle Paleolithic at Hohle Fels, Germany

2021 ◽  
Vol 2021 (30) ◽  
Author(s):  
Veerle Rots ◽  
Justin Coppe ◽  
Nicholas Conard
Keyword(s):  
Life History ◽  
Evolutionary Development ◽  
Functional Study ◽  
Middle Paleolithic ◽  
Projectile Technology ◽  
Excellent Preservation ◽  
The Rich ◽  
Pointed End ◽  
The University

During the 2020 season at Hohle Fels Cave in the Ach Valley of southwestern Germany the excavation team from the University of Tübingen recovered a bifacial leaf point in archaeological horizon (AH) X. This horizon is the fifth deepest of the Middle Paleolithic horizons at the site and is located roughly 120 cm beneath the base of the rich Aurignacian layers of the cave. The new leaf point, or Blattspitze in German, is the first artifact of its kind found in situ in the Swabian caves since Gustav Riek’s excavation at Haldenstein Cave near the source of the Lone River recovered two leaf points in excellent preservation in 1936. The new find allowed our team to conduct the first techno-functional study of a freshly recovered leaf point from the European Middle Paleolithic. This study demonstrates that the leaf point was hafted at the less pointy end of the artifact. The leaf point bears clear damage to the pointed end of the artifact that occurred during a hunting episode. A Neanderthal knapper further damaged the tool during an attempt to resharpen and rejuvenate the tool. This damage was likely the reason the knapper discarded the leaf point at Hohle Fels. This result and a re-examination of the two leaf points from Haldenstein Cave indicate that late Neanderthals used Blattspitzen for hunting large game. The current results do not explicitly prove that spears with hafted leaf points were always thrown or used as thrusting spears, and one can easily imagine scenarios in which a weapon of this kind could be used in both ways. Ideally, the ongoing excavation at Hohle Fels will recover more leaf points, which will give us the opportunity to document the technological variability of this kind of tool with regard to their manufacture, function and life history. We also view the current research at Hohle Fels as an excellent opportunity to gain a better and more strongly contextualized understanding of the technological system linking lithic, botanical and osseous technologies during this phase of the Middle Paleolithic. This paper also considers the place that hafted leaf points have within the broader evolutionary development of hunting and projectile technology.

Functional significance of compensatory overloaded rat fast muscle

1982 ◽  
Vol 52 (2) ◽  
pp. 473-478 ◽  
Author(s):  
R. R. Roy ◽  
I. D. Meadows ◽  
K. M. Baldwin ◽  
V. R. Edgerton
Keyword(s):  
Biochemical Properties ◽  
Slow Muscle ◽  
Repetitive Stimulation ◽  
Contractile Properties ◽  
Sectional Area ◽  
Shortening Velocity ◽  
Cross Sectional ◽  
Time To Peak ◽  
Isometric Twitch

Chronic overload of a skeletal muscle by removing its synergists produces hypertrophy and marked changes in its metabolic and biochemical properties. In this study alterations in the contractile properties of the plantaris 12–14 wk after bilateral removal of the soleus and gastrocnemius were investigated. In situ isometric and isotonic contractile properties of overloaded plantaris (OP), normal plantaris (NP), and normal soleus (NS) were tested at 33 +/- 1 degree C. Op were 97% heavier than NP and produced 43 and 46% higher twitch (Pt) and tetanic (Po) tensions. However, NP produced more tension per cross-sectional area than OP (mean 26.2 vs. 21.6 N/cm2; P less than 0.001). Isometric twitch time to peak tension (TPT) and half-relaxation time (1/2RT) were significantly longer in OP (mean 36.4 vs. 32.5 ms and 23.9 vs. 18.4 ms). Mean maximum shortening velocity (Vmax, mm/s per 1,000 sarcomeres) were 34.1 for NP and 18.1 for OP (P less than 0.001). The degree of conversion toward the Vmax of NS was 74% compared with only 19 and 14% for TPT and 1/2RT. OP produced a higher proportion of Po at a given stimulation frequency than NP and showed less fatigue than NP after repetitive stimulation. Chronic overload of the fast plantaris modified to varying degrees the contractile properties studied toward that resembling a slow muscle. Although the maximum tension of OP was markedly enhanced it was not in proportion to the increase in muscle mass.

scholarly journals THE LAND BEHIND THE LAND BEHIND BAGHDAD: ARCHAEOLOGICAL LANDSCAPES OF THE UPPER DIYALA (SIRWAN) RIVER VALLEY

Iraq ◽  
2017 ◽  
Vol 79 ◽  
pp. 47-69 ◽  
Author(s):  
Jesse Casana ◽  
Claudia Glatz
Keyword(s):  
Bronze Age ◽  
Physical Geography ◽  
River Valley ◽  
Archaeological Sites ◽  
Archaeological Survey ◽  
Near Eastern ◽  
The North ◽  
Wide Range ◽  
Regional Project ◽  
The Rich

While the Diyala (Kurdish Sirwan) River Valley is storied in Near Eastern archaeology as home to the Oriental Institute's excavations in the 1930s as well as to Robert McC. Adams’ pioneering archaeological survey, The Land Behind Baghdad, the upper reaches of the river valley remain almost unknown to modern scholarship. Yet this region, at the interface between irrigated lowland Mesopotamia and the Zagros highlands to the north and east, has long been hypothesized as central to the origins and development of complex societies. It was hotly contested by Bronze Age imperial powers, and offered one of the principle access routes connecting Mespotamia to the Iranian Plateau and beyond. This paper presents an interim report of the Sirwan Regional Project, a regional archaeological survey undertaken from 2013–2015 in a 4000 square kilometre area between the modern city of Darbandikhan and the plains south of Kalar. Encompassing a wide range of environments, from the rugged uplands of the Zagros front ranges to the rich irrigated basins of the Middle Diyala, the project has already discovered a wealth of previously unknown archaeological sites ranging in date from the Pre-Pottery Neolithic through the modern period. Following an overview of the physical geography of the Upper Diyala/Sirwan, this paper highlights key findings that are beginning to transform our understanding of this historically important but poorly known region.

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