Top PDF A Study on Biological Threats to Texas Freshwater Resources

A Study on Biological Threats to Texas Freshwater Resources

A Study on Biological Threats to Texas Freshwater Resources

Our findings showed that triploid grass carp consumed giant salvinia, which is the first time this has been documented in a controlled setting. Previous research concluded that triploid grass carp would not consume giant salvinia even if it is the only plant available, most likely because the plant contains a metabolic inhibitor that is toxic to fish if consumed in quantity (Sanders, unpubl. data). Our research indicates that juvenile triploid grass carp will consume giant salvinia when presented as both a single food source as well as select for it in a community. It should be noted that giant salvinia utilized in our study was a mix of secondary and tertiary growth forms, and it is likely that consumption rate and overall preference varies between growth forms, with primary and secondary growth preferred over dense tertiary growth due to their relative ease of handling. Despite contradicting previous research, this conclusion is not entirely
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Diversity, distribution and long-term changes in freshwater Unionidae in Texas

Diversity, distribution and long-term changes in freshwater Unionidae in Texas

In the summer of 2012, we spent three wonderful weeks at the Cornell University Biological Field Station on Lake Oneida doing extensive molluscs survey and enjoying the warm hospitality of its faculty, staff, and especially the Station’s Director, Lars Rudstam. This trip was a result of several discussions with Lars in the preceding years about a potential collaboration between the Great Lakes Center and the Cornell Biological field station at Shackelton Point to understand the possible reasons for the decline in the molluscan diversity in Lake Oneida. This lake was a subject of multiple studies at the beginning of the 20 th century conducted by a prominent malacologist Frank Baker, who published several detailed descriptions of its molluscan fauna, including quantitative data. According to Baker, in the early 20 th century this lake hosted an abundant and diverse molluscan community of 41 species, including 12 unionid bivalves. However, later studies conducted by Willard Harman and John Forney in 1967, and later in 1992-1995, stated that due to habitat loss, introduction of invasive species, and other aspects of human activity, the diversity of molluscs has dramatically declined. By the mid-1990s, 20 species of molluscs found in the lake in 1918 had disappeared, indicating a 50% decline in diversity. At the same time, at least 11 species of molluscs were introduced, including the zebra mussels and quagga mussels, which have had a devastating effect on the native unionid mussels. During our preliminary study of molluscs of Lake Oneida in 2010, we found 19 species, including 6 species that were previously listed as lost, suggesting at least a partial recovery in the molluscan community. In 2012 we collected 272 samples, paying special attention to historical sites that were previously sampled by Baker and other scientists. Identification of these historical sites from literature wasn’t easy after 100 years of development, and required a lot of “detective” work. Preliminary analysis of the collected samples indicated that at least 32 species of molluscs are currently present in Oneida Lake. Two species were found for the first time, including a very rare native snail Armiger crista (Photo 2) and the exotic snail Cipangopaludina chinensis (Chinese mystery snail) (Photo 3). Only dead shells of native Unionidae were found during our study, suggesting complete extirpation of these bivalves from the lake, most likely due to the impact of zebra mussels. The overall mollusc assemblage of Oneida Lake is currently dominated by invasive species, especially zebra and quagga mussels. These two dreissenid species comprise over 90% of the wet total mass of all molluscs in the lake (Photo 4). Results of this study will be presented at the next meeting of the International Association for Great Lakes Research in 2013. (2012)
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Diversity, distribution and long-term changes in freshwater Unionidae in Texas.

Diversity, distribution and long-term changes in freshwater Unionidae in Texas.

In the summer of 2012, we spent three wonderful weeks at the Cornell University Biological Field Station on Lake Oneida doing extensive molluscs survey and enjoying the warm hospitality of its faculty, staff, and especially the Station’s Director, Lars Rudstam. This trip was a result of several discussions with Lars in the preceding years about a potential collaboration between the Great Lakes Center and the Cornell Biological field station at Shackelton Point to understand the possible reasons for the decline in the molluscan diversity in Lake Oneida. This lake was a subject of multiple studies at the beginning of the 20 th century conducted by a prominent malacologist Frank Baker, who published several detailed descriptions of its molluscan fauna, including quantitative data. According to Baker, in the early 20 th century this lake hosted an abundant and diverse molluscan community of 41 species, including 12 unionid bivalves. However, later studies conducted by Willard Harman and John Forney in 1967, and later in 1992-1995, stated that due to habitat loss, introduction of invasive species, and other aspects of human activity, the diversity of molluscs has dramatically declined. By the mid-1990s, 20 species of molluscs found in the lake in 1918 had disappeared, indicating a 50% decline in diversity. At the same time, at least 11 species of molluscs were introduced, including the zebra mussels and quagga mussels, which have had a devastating effect on the native unionid mussels. During our preliminary study of molluscs of Lake Oneida in 2010, we found 19 species, including 6 species that were previously listed as lost, suggesting at least a partial recovery in the molluscan community. In 2012 we collected 272 samples, paying special attention to historical sites that were previously sampled by Baker and other scientists. Identification of these historical sites from literature wasn’t easy after 100 years of development, and required a lot of “detective” work. Preliminary analysis of the collected samples indicated that at least 32 species of molluscs are currently present in Oneida Lake. Two species were found for the first time, including a very rare native snail Armiger crista (Photo 2) and the exotic snail Cipangopaludina chinensis (Chinese mystery snail) (Photo 3). Only dead shells of native Unionidae were found during our study, suggesting complete extirpation of these bivalves from the lake, most likely due to the impact of zebra mussels. The overall mollusc assemblage of Oneida Lake is currently dominated by invasive species, especially zebra and quagga mussels. These two dreissenid species comprise over 90% of the wet total mass of all molluscs in the lake (Photo 4). Results of this study will be presented at the next meeting of the International Association for Great Lakes Research in 2013. (2012)
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Use of literature mining for early identification of emerging contaminants in freshwater resources

Use of literature mining for early identification of emerging contaminants in freshwater resources

Chemical and microbial contaminants in the aquatic environment pose a potential threat to humans and to ecosys- tems. Humans may be exposed to contaminants in water resources when used for drinking water production, agricul- ture, aquaculture or recreation. Climatological, social and demographic changes, as well as the increasing sensitivity of analytical techniques, may result in the augmented detection of contaminants. Recent research has shown that it takes about 15 years from the time of the first scientific study mentioning the presence of a contaminant in the envi- ronment for the issue to peak in scientific attention and regulatory action. One possible factor influencing this lengthy period is that the first article becomes lost in the vast number of publications. In this study, we therefore developed a methodology using literature mining to identify the first scientific study which reports the presence of a contaminant in the aquatic environment. The developed semi-automated methodology enables health and environment agen- cies to inform policy makers about contaminants in the aquatic environment that could be significant for public and environmental health in national, international and river basin settings. The methodology thereby assists the proactive governance of emerging contaminants in the aquatic environment. This was illustrated by a retrospective analysis of the period of emergence in the Netherlands of: (1) perfluorooctanoic acid in surface water, and (2) biological indus- trial wastewater treatment systems as potential infection sources for Legionnaires´ disease.
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Global impacts of energy demand on the freshwater resources of nations

Global impacts of energy demand on the freshwater resources of nations

Findings in the present study can be placed within an emerging body of literature that suggests an imbalance in the use of natural resources (29, 30, 65–67) with exchanges between developed and less-developed countries having become increasingly ecologically unequal. The analysis of virtual freshwater transfers to affluent eastern provinces of China from other provinces in ref. 60 highlights that such an imbalance in resource use can also occur within countries. To address such transfers, ref. 60 suggests a number of policy mechanisms based on shared producer and consumer responsibility (68) that could be implemented and used to fund agricultural and industrial freshwater efficiency programs. In the context of findings in the present study, we would suggest that such mechanisms could also be used at the global level to ensure both the security of energy supply in areas where final demand lies and to address social, economic, and environmental issues where freshwater consumption to meet this demand originates. Ultimately, as argued by refs. 25 and 69, the analysis presented here provides information that can be used by policy makers to identify critical sectors and geographic regions at the water–energy nexus. When developing energy policy, deci- sions can then be made to invest in protecting these critical points to reduce social, environmental, and economic burdens. For ex- ample, in the 1970s, the government of Saudi Arabia identified threats to territorial freshwater resources as a major issue for the oil industry, such that the industry is now based almost entirely on the use of desalination technology and brackish water (70), a fact reflected in our analysis which finds comparatively low freshwater consumption in this region. Our analysis provides information that could enable transfer of resources between countries to en- able similar sectorial changes to protect freshwater resources and ensure security of the energy supply.
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Resources and Threats of the Eco-Tourism Development in Georgia

Resources and Threats of the Eco-Tourism Development in Georgia

Abstract: Ecological tourism can play a certain role in solving the problems of environment protection and sustainable and safe development of the country. The article considers some specific problems of the eco-tourism development in Georgia. The results of the study of the tourism potential in the regions in 2009-2014 revealed that: Georgia has substantial means to develop eco-tourism. This is true not only for the protected areas, but also for individual natural and geographical areas of the different regions (historical areas) of the country. The distinctive feature of the country’s eco-tourism potential is particularly diversified relief forms and natural eco-systems, in particular, intense variation of the landscapes and great contrasts between them (seaside and mountain, humid subtropical and arid zone, river gorges and steppe landscapes alternate over small areas), widely distributed endemic biological species, and traditional ethnographic, farming and domestic cultural forms survived in the historical regions (mostly in the mountains) of the country. The principal eco-tourism value is the natural eco-systems being only insignificantly modified due to industrial changes and maintaining their “natural originality”. In addition, numerous remnants of historical and cultural heritage give them a certain value. They naturally merge with the environment and not dominate over it, but add to its beauty. The threats to the environment are mostly associated with an increasing anthropogenic “aggression”, destruction of the traditional mode of nature management meaning certain degree of responsibility and deficient environmental laws and mechanisms of their execution. The problem is further aggravated by the fact that due to the limited territories, the eco-systems of the country are particularly sensitive to technogenic pressure. Concrete eco-tourism projects must inevitably envisage preliminary geo-ecological works.
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A Review on Present Status, Potentials and Threats of Freshwater Fish Biodiversity of Nadia District, West Bengal, India

A Review on Present Status, Potentials and Threats of Freshwater Fish Biodiversity of Nadia District, West Bengal, India

Making of unscientific dam, Occupancy of river bed by people, withdrawal of water for irrigation, deforestation, urbanization and industrialization has caused drastic changes the river bed and hydrology in terms of natural flow. Out of these, wanton killing, overexploitation of fishery resources and over-fishing due to high economic value has exacerbated the vulnerability of the fish population in different ecosystem of in the district of Nadia like other places of West Bengal. The most comprehensive, effective and evaluating procedure for the conservation status of animal and plant species in the world is IUCN. There are several species in threaten and endangered condition in West Bengal. Here required data is still insufficient and unavailable of many fishes for IUCN red list evaluation. So, proper survey is needed for those fishes.
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UTILIZATION OF WEEDS AS BIOLOGICAL RESOURCES AND AS A MANAGEMENT TOOL

UTILIZATION OF WEEDS AS BIOLOGICAL RESOURCES AND AS A MANAGEMENT TOOL

It is accepted that in some situations in agricultural fields, there are huge crop losses due to excessive and unmanaged weed growth.. However, as discussed in this essay, Asia-Pacific countries should look at the positive aspects of weeds as well; i.e. their utilization as resources. As indicatedabove, proper utilization of weeds can contribute significantly to enhance the income of the poor farmers, besides giving various other benefits in various ecosystems.

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THE UNIVERSITY OF TEXAS SCHOOL OF LAW THE OIL, GAS AND ENERGY RESOURCES LAW SECTION OF THE STATE BAR OF TEXAS

THE UNIVERSITY OF TEXAS SCHOOL OF LAW THE OIL, GAS AND ENERGY RESOURCES LAW SECTION OF THE STATE BAR OF TEXAS

Although early Texas cases held that the leasehold estate granted a possessory interest, they did not always interpret the leasehold estate as a fee simple determinable estate. 7 However, in Stephens County v. Mid-Kansas Oil & Gas Co., 8 the Supreme Court of Texas held that the typical oil and gas lease conveyed to the lessee the ownership of oil and gas in place for so long as oil or gas was produced in paying quantities. Although the leasehold interest was held to be a fee simple interest, since theoretically the estate could continue indefinitely, due to the language of the habendum clause, “so long as,” the interest conveyed was determined to be a defeasible fee interest since upon cessation of production in the secondary term, the leasehold estate would terminate. The court arrived at its decision by ascertaining the intent of the parties as stated in the specific language of the habendum clause of the lease. The same result is reached in leases containing a habendum clause stating, “so long thereafter as.”
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Scott A. Stockwel l. Department of Biological Science s Texas Tech University Lubbock, Texas INTRODUCTION

Scott A. Stockwel l. Department of Biological Science s Texas Tech University Lubbock, Texas INTRODUCTION

Pedipalp chela length in adult males less than twice chela width, in females and immature males greater tha n twice chel width ; pedipalp chelae weakly carinate ; metasomal segment II wi[r]

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Antagonistic effects of biological invasion and environmental warming on detritus processing in freshwater ecosystems

Antagonistic effects of biological invasion and environmental warming on detritus processing in freshwater ecosystems

this system, at least, it appears that the larger size of the invasive species and the effect of environmental warming will partly offset this negative effect through increased resource processing in the invasive species at higher tem- peratures. Uniquely, this study has shown that the replace- ment may not impact ecosystem functioning as much as previously thought if other factors enhance the shredding activity of the invasive species, although the higher preda- tory efficiency of D. villosus may reduce overall shredding through predation on other macroinvertebrate shredders (Dodd et al. 2014). Our findings therefore constitute a case of antagonistic stressors (Jackson et al. 2016) and provide new insights into the interactions that link environmental thermal regimes with ecological responses across multiple levels of organisation (i.e., metabolic processes of individu- als, populations dynamics of invasive and native species, and ecosystem functioning; cf. Woodward et al. 2010). The wider application of MTE analysis, with respect to inva- sive species, could prove beneficial in terms of identifying ‘risk’ species during horizon scanning. The results of this study will help predict the possible effect that D. villosus will have on freshwater ecosystems as it displaces native species under a warming climate. While estuaries, lakes, and stream outlets represent the current strongholds of D. villosus, suitable habitats exist in lower order streams (especially where channelised) and colonisation may be restricted only by stochastic processes (Altermatt et al. 2016), hence further colonisation of headwaters is likely to be a matter of time for this and many other Ponto–Cas- pian species (Gallardo and Aldridge 2015). Studying and understanding these complex linkages and feedbacks in more detail is vital if ecologists are to deliver more effec- tive modelling of invasion dynamics to inform prevention and mitigation measures.
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Human Resources. Employee Retirement System of Texas (ERS)

Human Resources. Employee Retirement System of Texas (ERS)

The Texas Tuition Promise Fund will give you an important opportunity to prepay and save for your child’s future education at an accredited public or private junior/ community college as well as 4-year colleges and universities through the country. The Texas Tuition Promise Fund is a Section 529 prepaid tuition plan. The

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Freshwater resources under success and failure of  the Paris climate agreement

Freshwater resources under success and failure of the Paris climate agreement

Our estimate that 26.8 % of global population today live under absolute water scarcity (> 1000 p/fu) is within the range of 21.0 %–27.5 % (average 24.7 %) reported by pre- vious studies applying the WCI on river basin level (Gerten et al., 2013; Arnell and Lloyd-Hughes, 2014; Kummu et al., 2016). Estimates of future SSP populations living in river basins with > 1000 p/fu under present-day climate conditions are given by Arnell and Lloyd-Hughes (2014) who estimate a range of 39.5 %–54.2 % for the affected global population across different SSP scenarios. This is considerably higher than the range of our estimates of 31.5 %–44.9 %; but due to the lack of other comparable studies, it is not clear whether these discrepancies are caused by the choice of the hydrolog- ical model or by the difference in scale (basin or grid cell) at which the WCI is calculated. However, using the same hy- drological model as in our study, Gerten et al. (2013) esti- mate that 38.5 % of global population in the revised A2r sce- nario (Grübler et al., 2007) from the Special Report on Emis- sions Scenarios would live in river basins with > 1000 p/fu under current climate conditions, which is close to our es- timate of 41.0 % for the SSP3 scenario, to which the A2r scenario is comparable in terms of total population (12.3 bil- lion compared to 12.6 billion in 2100). In contrast, the cor- responding estimate by Arnell and Lloyd-Hughes (2014) is as high as 54.2 % for the SSP3 scenario, which indicates that using LPJmL to assess water scarcity generally tends to re- sult in lower estimates of future population affected by water scarcity.
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A study on Advanced Persistent Threats

A study on Advanced Persistent Threats

“An adversary that possesses sophisticated levels of expertise and significant resources which allow it to create opportunities to achieve its objectives by using multiple attack vectors (e.g., cyber, physical, and deception). These objectives typically include establishing and extending footholds within the information technology infrastructure of the targeted organizations for purposes of exfiltrat- ing information, undermining or impeding critical aspects of a mission, program, or organization; or positioning itself to carry out these objectives in the future. The advanced persistent threat: (i) pursues its objectives repeatedly over an ex- tended period of time; (ii) adapts to defenders’ efforts to resist it; and (iii) is determined to maintain the level of interaction needed to execute its objectives”. This definition provides a good base for distinction between traditional threats and APTs. The distinguishing characteristics of APTs are: (1) specific targets and clear objectives; (2) highly organized and well-resourced attackers; (3) a long-term campaign with repeated attempts; (4) stealthy and evasive attack techniques. We elaborate on each of these characteristics below.
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Study on the Threats to Vultures (Aegypiinae) in Macedonia

Study on the Threats to Vultures (Aegypiinae) in Macedonia

Factors that vultures faced and resulted with their number decline were especially intensive after the World War II. Most of them led to the total disappearance of vultures in some regions and significant number decline in other regions. In continuation we give overview of the identified threats as reasons for the decline with the known cases. Data on these cases were derived from literature sources and rarely by interviews with experts that could provide some data as well as local inhabitants (farmers, shepherds, hunters etc.). The threats were analyzed for each species separately and their importance was assessed. The assessment performed is based only on accessible data and thus can not provide complete coverage of the situation. However, the conclusions can be used as a suitable base for the preparation of conservation plans of vultures in Macedonia and will be helpful in the preparation of the National Action Plan of Recovery and Conservation of Vultures.
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Māori and freshwater: a comparative study of freshwater co-management agreements in New Zealand

Māori and freshwater: a comparative study of freshwater co-management agreements in New Zealand

Water governance is a significant local, regional, and national challenge that echoes parallel concerns held around the world. New Zealand has a unique approach to reconciliation between colonised Indigenous Peoples and state control, which is often cited by other Indigenous societies as a model worth investigating. Over the past 20 years, Treaty settlements have been established that have seen the ownership of the beds of lakes and rivers returned to their rightful iwi. This has created the need for co- management agreements in order to meet the needs and challenges facing effective management between Indigenous people and local government. Representative, adaptive, exercising rangatiratanga and the inclusion of Indigenous knowledge are all elements essential to co-management regimes in New Zealand. This research aims to identify how local authorities are responding to and providing co-management avenues for Māori involvement in freshwater governance and establish how effective the various co-management regimes studied are at incorporating Māori involvement. A comparative analysis of three co-management regimes in New Zealand, Te
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Increasing pressure on freshwater resources due to terrestrial feed ingredients for aquaculture production

Increasing pressure on freshwater resources due to terrestrial feed ingredients for aquaculture production

The feed ingredients are of animal origin ( fishery products, terrestri- al livestock products, terrestrial invertebrate products), of plant origin (cereal protein products, oilseed protein products, pulse and grain le- gume seed products, miscellaneous plant protein products), single cell protein, lipids (oils and fats), premixes, additives, fertilizers and ma- nures. Feed ingredients that are used in aquafeeds investigated here are explained in detail in Tacon et al. (2009) . A special case is Red swamp craw fish, as an established or encouraged forage crop serves to provide the basis of a food web from which craw fish derive most of their nutritional needs and is therefore not included in Fig. 3 . In Fig. 3 the dietary habit of each species investigated in this study is indicated. The freshwater fishes include herbivores, planktivores, carnivores and omnivores. With the exception of rainbow trout (piscivore) and mullet (carnivore in the fry life stage and omnivore in the juvenile and growout stage) the diadromous and marine fish species included are carnivores. All crustaceans in this study are omnivores, with Giant tiger prawns being planktivores in early life stages, changing their feeding behavior later on to carnivorous. The differences in feed composition have a sig- ni ficant effect on the water footprint, which we will allude to in detail.
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Modelling freshwater resources use and the economic impacts of demand-driven water scarcity

Modelling freshwater resources use and the economic impacts of demand-driven water scarcity

Currently, there is a growing number of expert- and policy-maker platforms such as the World Water Forum, the International Network of Basin Organizations or the World Water Week in Stockholm, focusing on water management issues from a local to a global level. Furthermore, the 2030 Water Resources Group through its private-public-civic society collaboration aims at solving the mismatches between demand and supply of freshwater by 2030. In the recent Sustainable Development Goals (SDG) framework, water is introduced as a major topic through a standalone goal (Goal 6). This SDG is emphasising the human rights dimension of access to drinking water, sanitation and hygiene (WASH) in line with the previous Millennium Development Goals (Target 7.C). Alongside, the aim of sustainable freshwater use is set through sub-goal 6.4. Thus, by 2030, it is set “[to] substantially increase water-use efficiency across all sectors and [to] ensure sustainable withdrawals and supply of freshwater to address water scarcity, and [to] substantially reduce the number of people suffering from water scarcity”. An expanding body of academic work has focused on the topic of future demand-driven water scarcity coming from socioeconomic development and climate change. This was facilitated by the methodological improvements in water demand estimations and data collection. Due to the distributed nature of water withdrawals, quantitative evaluations of freshwater uses are determined indirectly through estimation efforts, notably when assessed at a larger scale such as a country or the globe. More detailed national statistics combined with remote sensing data of crop growth and groundwater depletion have enabled a better understanding of evapotranspiration patterns and irrigation water uses. Furthermore, water life-cycle analyses for different industrial activities have allowed for a more detailed quantification of water inputs in sectors outside agriculture. Thus, such estimations in conjunction with projections of demand levels coming from economic and population growth have revealed a water “supply gap” which, by 2030, could be in the order of 2000km 3 (McKinsey 2009) representing a third of the estimated
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Freshwater bivalve fauna in the western ghats rivers of karnataka, India: diversity, distribution patterns, threats and conservation needs

Freshwater bivalve fauna in the western ghats rivers of karnataka, India: diversity, distribution patterns, threats and conservation needs

In some part of India sand mining affect the river aquatic biota but there are no data available regarding the impact of sand mining on bivalves from the Western Ghats. According to the report by IUCN, Pseudomulleria dalyi (EN) is the only threatened bivalve species. Its population in River Tunga is threatened by the overharvesting of the fishes (using explosive and toxic chemicals) that provide P. dalyi with a host to complete its life cycle. Several bivalves are predominantly susceptible to water pollution, as they accumulate toxins quickly (Salanki et al., 2003), and have been unfavorably affected in polluted habitats. Anthropogenic (bathing and washing), agricultural pollution, tourism and fishing using chemicals and explosives are all major threats to bivalve population. To avoid this effect on freshwater bivalves in future continuous monitoring of pollution aspects and population, ecological studies are needed. In some part of Western Ghats region, freshwater bivalves are used for minor ailments by native people but no work on has been done on these aspects (Prabhakar and Roy, 2009). The data on bivalve diversity and other studies are not complete so the statuses of many species are not known. The freshwater bivalve population is declining worldwide (Bogan, 1993), conservation of this fauna is vital due to their unique role in the river ecosystem. Apart from this, they form a part of our natural heritage and biodiversity. Hence they should be conserved for future generations and their loss will have negative consequences for the freshwater ecosystems in which they live and on which we depend.
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A Study and Review on Advanced Persistent Threats

A Study and Review on Advanced Persistent Threats

Advanced Persistent Threats (APTs) are a cybercrime category directed at business and political targets. APTs require a high degree of stealithiness over a prolonged duration of operation in order to be successful. The attack objectives therefore typically extend beyond immediate financial gain, and compromised systems continue to be of service even after key systems have been breached and initial goals reached. Definitions of precisely what an APT is can vary widely, but can best be summarized by their named requirements:

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