scholarly journals Structure and Biodiversity of Rhodolith Seabeds: A Special Issue

Diversity ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 300 ◽  
Author(s):  
Fernando Tuya

Rhodolith seabeds function as ‘ecosystems engineers’, which globally provide a range of ‘ecosystem services’. However, knowledge on the structure, composition and distribution of rhodolith seabeds is still lacking. This Special Issue comprises six articles, addressing specific questions of rhodolith seabeds, and covering a wide range of topics. Two papers provide new large-scale information on the presence, structure and distribution of rhodolith beds at two southern hemisphere areas, in particular continental shelfs off South Africa and Brazil. Another two studies contributed to the discovery on new algal species from rhodolith beds, including Sporolithon franciscanum, a new rhodolith-forming species from Brazil, and the small benthic alga Schizocladia ischiensis. In terms of associated fauna, the taxonomic composition and patterns of abundance of decapod crustaceans are described in another article, including the description of a depth-partitioning in the abundance of juveniles and adults of the crab Nanocassiope melanodactylus. Rhodoliths are often present in fossilized deposits, so we can track changes in their presence with climate fluctuations. High temperatures during the Eocene and widespread oligotrophic conditions are finally connected with low abundances of rhodolith beds at mid and high latitudes, despite a larger presence at equatorial regions.

2012 ◽  
Vol 90 (8) ◽  
pp. 807-815 ◽  
Author(s):  
Michael J.S. Belton

Recent space observations of cometary nuclei show evidence of internal (cryovolcanic) activity while retaining aspects of their primitive origins. Using discoveries made during the two most recent cometary encounters: EPOXI at 103P/Hartley 2 and Stardust-NExT at 9P/Tempel 1, we test a hypothesis for their physical evolution, which, if true, could provide a unified basis for understanding the relative ages of their surfaces and the causes of a wide range of cometary activity. We show: (i) that the categorization of 103P/Hartley 2 as hyperactive is not a reflection of the extent of activity over the surface of the nucleus for which we find a normal H2O production rate; (ii) that the heterogeneous spatial distribution of CO2 and H2O in the inner comae of 9P/Tempel 1 and 103P/Hartley 2 is best explained by processes associated with cometary activity rather than the presence of primitive compositional heterogeneities in the nucleus; and (iii) that most of the quasi-circular depressions seen on the surface of 9P/Tempel are the result of outburst activity. The apparent absence of circular depressions and large scale layering on 103P/Hartley 2 present a challenge to the evolutionary hypothesis although the small size of its nucleus may ultimately provide an explanation.


2014 ◽  
Vol 26 (4) ◽  
pp. 435-435
Author(s):  
Koichi Osuka

As a disaster-prone country, Japan has endured many earthquake disasters. The latest cases include the 1995 Great Hanshin-Awaji earthquake disaster, the 2004 Niigata Chuetsu earthquake, and the 2011 Great East Japan earthquake. Since the 1995 Great Hanshin-Awaji earthquake in particular, many robot researchers have started undertaking the research and development of rescue robots. Their practical applications have a long way to go, so to continue ongoing robot research and development, we should also be aware that comparatively few researchers and engineers are actually engaged in such research and development. Great earthquakes (or tsunami) are both rare and unpredictable, which makes it very difficult to establish research policies for rescue robots intended for specialized use in disaster response. We should also realize that Japan is almost constantly hit by one or another every year – e.g., the typhoons that hit Japan directly every year and themselves triggering other disasters caused by landslides or avalanches due to heavy rainfall. The Japanese populace is so accustomed to such happenings but, nevertheless, few actions have been taken unlike those against large-scale earthquakes. It is often said that an effective disaster response system can only be developed after we have experienced many actual disasters. It then occurs to us that we must first construct disaster response systems – rescue robots, etc. – directly targeting daily natural disasters. Any large-scale disaster response system can be built on such constant efforts. On the other hand, any disaster response system against daily natural disasters could only be developed by locally domiciled researchers and engineers. This makes us feel that it is possible to increase the number of personnel who become involved in disaster response research and development. Based on the above context, this special issue provides a wide range of articles on region-specific disasters and disaster response actions, focusing on their localities and specialties. We sincerely hope that this special issue will help in promoting research and development on rescue robots and putting them to practical use.


2021 ◽  
Vol 5 ◽  
Author(s):  
Kevin Queenan ◽  
Soledad Cuevas ◽  
Tafadzwanashe Mabhaudhi ◽  
Michael Chimonyo ◽  
Rob Slotow ◽  
...  

Food systems face growing challenges to meet targets of Zero Hunger (SDG 2), and South Africa is no exception given its triple burden of malnutrition, foodborne disease outbreaks, and threats of climate change to food production. Broiler meat is South Africa's most affordable meat option, supporting household food and nutrition security. Although considered healthier and less environmentally harmful than ruminant meat, it is not without food safety risks and environmental impacts. This research aimed to present the foremost commercial broiler system narratives in South Africa, around targets of SDG 2, and to discuss key considerations for policymakers. Twenty-nine key informants and stakeholders, purposively selected to cover a wide range of opinions, participated in semi-structured interviews. Transcripts underwent a qualitative framework analysis. Results showed a highly efficient system, dominated by a small number of interlinked large-scale actors, vulnerable to competition from cheaper imports, yet pressurized to maintain high food safety and environmental impact standards, with a price-sensitive consumer base. Existing policies lack integration and enforcement capacity, and are undermined by siloed government departments, and mistrust and power struggles between public and private sectors. We propose removal of silo walls, and trust building through participatory policy development, with collaborative and transformative public-private partnerships that are designed to build capacity to deliver sustainable solutions.


2019 ◽  
Vol 6 (4) ◽  
pp. 427-432
Author(s):  
Nishesh Sharma ◽  
Ajay Singh ◽  
Felicia Lalremruati ◽  
_ Vanlalmalsawmi ◽  
Rohit Sharma

Industrial revolutions, advancements in health care, pharmaceuticals, transportation can be attributed to advancements made in the field of science and technology. Environment and natural resources has paid a heavy cost for most of industrial development. Rapid depletion of non-renewable sources of energy eventually leading towards the energy crisis, direct or indirect release of industrial effluents into soil and natural water bodies, global warming are among major consequences of industrialization. Ever since these environmental concerns have been recognized substantial studies have been conducted to minimize, control pollution and restore environment and natural resources. Among several measures cultivation of algae on large scale stands out to be a multipurpose solution. Inherent potential of microalgae species to accumulate lipids makes algae an efficient source of biofuel. Beside this ability of algae to detoxify polluted water and industrial effluent support utilization of algae for environment management and restoration. Efficient CO2 fixation, ability to tolerate wide range of environmental conditions, minimal nutritional requirements further support commercial cultivation of algal species to achieve their widespread application. However, efforts are required to develop large scale cultivation protocols (beyond the range of photobioreactors) so as to achieve practical applicability of algae and their products. Alongwith, cultivation protocols there is simultaneous need of either selection of naturally occurring high yielding strains / species or genetic improvement. Standardization of optimum cultivation conditions along with harvesting procedure is equally important.


2014 ◽  
Vol 8 (1) ◽  
pp. 154-154
Author(s):  
Mingjin Chu

The Open Civil Engineering Journal, which is one of the most relevant international journals in civil engineering area, wishes to promote the latest researches in engineering structures. This special issue contains 8 invited outstanding articles covering a wide range of topics. We have assembled recent studies in the field of several typical structures, attempting to provide a glimpse into the wide range of engineering problems. It is expected that the special issue will benefit researchers and engineers who are interested in the design of protective structures and stimulate the research interests in this important an d promising area of civil engineering. A brief overview of each article published in this special issue is provided here. In “Experimental Study on Assembled Monolithic Concrete Shear Walls Built with Precast Two-way Hollow Slabs” , Zhijuan Sun et al. present a quasi-static experiment on one reinforced concrete shear wall and two shear walls built with precast two-way hollow slab. Test result shows that the new type of shear walls experienced the loading process from the whole wall to the portioned wall due to the internal and vertical joints of the wall body, which can be applied in practical construction. In “Study on Metering Scheme of Seismic Experiment for Shear Wall Built with Precast Hollow Slab” , Zhijuan Sun et al. present the measuring scheme of shear wall deformation and steel strain. The special mechanical characteristic of the shear wall built with precast two-way hollow slab is the relative deformation of the concrete on both sides of vertical joint. The study shows that the measuring methods of shear wall deformation and relative deformation are reasonable and feasible. In “Experimental Study on Precast Concrete Shear Walls with Different Hollow Slabs” , Qinyan Zhao et al. present a test on two shear walls built with precast two-way hollow slab with different details. The study shows that brittle shear failure can be avoided and the failure behaviors tend to evolve from integral wall to the combination of wall and columns. Also, compressive capacity of walls can be affected by the dimension of transverse holes. In “Test Study on Strength and Permeability Properties of Lime -Fly Ash Loess Under Freeze-Thaw Cycles”, Zhiquan Zhang and Yufen Zhang present a study on the engineering behaviors of lime-fly ash loess using uniaxial compressive test, fast direct shearing test and permeability test. Test data show that uniaxial compressive strength of lime-fly ash loess has good water stability and freeze-thaw stability, and can be applied in permafrost subgrade. In “Unloading Phenomena Characteristics in Brittle Rock Masses by A Large-scale Excavation in Dam Foundation”, Changgen Yan et al. investigate a large-scale excavation around the foundation of the dam. The characteristics of unloading rock masses were described with the acoustic wave velocity monitoring method. The unloading deformation has a direct temporal dependence, and increases quickly during the first 90 days, then with a slower rate from 90 to 180 days, and after that the unloading deformation will be small enough to be neglected In “A Review on Progressive Collapse of Building Structures” , Hao Wang et al. assess the recent studies on the progressive collapse of building structures from experimental study, numerical simulation and theoretical analysis. The design methods to prevent progressive collapse for building structures are also discussed. In “Damage Identification of Continuous Rigid Frame Concrete Bridge”, Shengnan Huang et al. present a large-scale experimental study on safety monitoring methodology for continuous rigid frame concrete bridge. Two load stages and ten different load steps were simulated to test various scenario of long-term loading and different levels of overload. Curva ture mode method was adopted to detect the damage during the exercises. In addition, the Finite-Element Analysis (FEA) was utilized, and the experimental recurring was verified positively through FEA model. In “Corrosion Monitoring Using Embedded Piezoelectric Sensors”, Lei Qin et al. develop a new type of corrosion detection technique for reinforced concrete. The technique used piezoelectric sensors to detect the ultrasonic signals during corrosion. The state of bonding layer of concrete and steel bar could be monitored. It can also detect the initial of corrosion and cracking of bonding layer. I am grateful to all the authors and reviewers for the contribution and support during the course of editing this special issue. Their prompt responses have made it possible for us to publish this special issue on time.


Author(s):  
V. C. Kannan ◽  
A. K. Singh ◽  
R. B. Irwin ◽  
S. Chittipeddi ◽  
F. D. Nkansah ◽  
...  

Titanium nitride (TiN) films have historically been used as diffusion barrier between silicon and aluminum, as an adhesion layer for tungsten deposition and as an interconnect material etc. Recently, the role of TiN films as contact barriers in very large scale silicon integrated circuits (VLSI) has been extensively studied. TiN films have resistivities on the order of 20μ Ω-cm which is much lower than that of titanium (nearly 66μ Ω-cm). Deposited TiN films show resistivities which vary from 20 to 100μ Ω-cm depending upon the type of deposition and process conditions. TiNx is known to have a NaCl type crystal structure for a wide range of compositions. Change in color from metallic luster to gold reflects the stabilization of the TiNx (FCC) phase over the close packed Ti(N) hexagonal phase. It was found that TiN (1:1) ideal composition with the FCC (NaCl-type) structure gives the best electrical property.


2015 ◽  
Vol 2 (2) ◽  
pp. 85-94
Author(s):  
Christina Landman

Dullstroom-Emnotweni is the highest town in South Africa. Cold and misty, it is situated in the eastern Highveld, halfway between the capital Pretoria/Tswane and the Mozambique border. Alongside the main road of the white town, 27 restaurants provide entertainment to tourists on their way to Mozambique or the Kruger National Park. The inhabitants of the black township, Sakhelwe, are remnants of the Southern Ndebele who have lost their land a century ago in wars against the whites. They are mainly dependent on employment as cleaners and waitresses in the still predominantly white town. Three white people from the white town and three black people from the township have been interviewed on their views whether democracy has brought changes to this society during the past 20 years. Answers cover a wide range of views. Gratitude is expressed that women are now safer and HIV treatment available. However, unemployment and poverty persist in a community that nevertheless shows resilience and feeds on hope. While the first part of this article relates the interviews, the final part identifies from them the discourses that keep the black and white communities from forming a group identity that is based on equality and human dignity as the values of democracy.


Author(s):  
О. Кravchuk ◽  
V. Symonenkov ◽  
I. Symonenkova ◽  
O. Hryhorev

Today, more than forty countries of the world are engaged in the development of military-purpose robots. A number of unique mobile robots with a wide range of capabilities are already being used by combat and intelligence units of the Armed forces of the developed world countries to conduct battlefield intelligence and support tactical groups. At present, the issue of using the latest information technology in the field of military robotics is thoroughly investigated, and the creation of highly effective information management systems in the land-mobile robotic complexes has acquired a new phase associated with the use of distributed information and sensory systems and consists in the transition from application of separate sensors and devices to the construction of modular information subsystems, which provide the availability of various data sources and complex methods of information processing. The purpose of the article is to investigate the ways to increase the autonomy of the land-mobile robotic complexes using in a non-deterministic conditions of modern combat. Relevance of researches is connected with the necessity of creation of highly effective information and control systems in the perspective robotic means for the needs of Land Forces of Ukraine. The development of the Armed Forces of Ukraine management system based on the criteria adopted by the EU and NATO member states is one of the main directions of increasing the effectiveness of the use of forces (forces), which involves achieving the principles and standards necessary for Ukraine to become a member of the EU and NATO. The inherent features of achieving these criteria will be the transition to a reduction of tasks of the combined-arms units and the large-scale use of high-precision weapons and land remote-controlled robotic devices. According to the views of the leading specialists in the field of robotics, the automation of information subsystems and components of the land-mobile robotic complexes can increase safety, reliability, error-tolerance and the effectiveness of the use of robotic means by standardizing the necessary actions with minimal human intervention, that is, a significant increase in the autonomy of the land-mobile robotic complexes for the needs of Land Forces of Ukraine.


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