title: Comparison of earthworm and chemical assays of the bioavailability of aged 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, and heavy metals in orchard soils

authors: Gaw, Sally K.

subjects: Bioavailability

abstract: Orchard soils can contain elevated concentrations of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE), 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p′-DDT), and heavy metals as a result of historical agrichemical applications. The bioavailability of p,p′-DDE, p,p′-DDT, As, Cd, Cu, and Pb from five field-aged New Zealand orchards and three grazing soils was assessed by using a 28-d bioassay with Aporrectodea caliginosa and chemical assays. Significant relationships were found between total soil and earthworm tissue concentrations for p,p′-DDE (p < 0.001), p,p′-DDT (p < 0.001), Cu (p < 0.001), and Pb (p < 0.01). Two neutral salt solutions, 0.01 M CaCl2 and 1 M NH4NO3, were used as surrogate measures of the bioavailability of heavy metals. Copper was the only heavy metal for which significant correlations were found between neutral-salt-extractable and earthworm tissue concentrations (p < 0.001). Up to 28% of the aged DDT residues were released from the soils by Tenax over a 24-h extraction period. Significant relationships (p < 0.01) between the Tenax-extractable and earthworm tissue concentrations for p,p′-DDE and p,p′-DDT showed that Tenax provides a good surrogate measure of the bioavailability of these compounds to A. caliginosa. Surprisingly, there was a similarly significant relationship (p < 0.001) between the total soil and earthworm tissue concentrations for p,p′-DDE and p,p′-DDT, suggesting that total soil concentrations alone were sufficient to predict uptake by A. caliginosa. These results demonstrate that the aged agrichemical residues in orchard soils, and particularly p,p′-DDE and p,p′-DDT, remain highly bioavailable to A. caliginosa despite decades of weathering and continue to present an environmental risk

text: Comparison of earthworm and chemical assays of the bioavailability of aged 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, and heavy metals in orchard soils Orchard soils can contain elevated concentrations of 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE), 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (p,p′-DDT), and heavy metals as a result of historical agrichemical applications. The bioavailability of p,p′-DDE, p,p′-DDT, As, Cd, Cu, and Pb from five field-aged New Zealand orchards and three grazing soils was assessed by using a 28-d bioassay with Aporrectodea caliginosa and chemical assays. Significant relationships were found between total soil and earthworm tissue concentrations for p,p′-DDE (p < 0.001), p,p′-DDT (p < 0.001), Cu (p < 0.001), and Pb (p < 0.01). Two neutral salt solutions, 0.01 M CaCl2 and 1 M NH4NO3, were used as surrogate measures of the bioavailability of heavy metals. Copper was the only heavy metal for which significant correlations were found between neutral-salt-extractable and earthworm tissue concentrations (p < 0.001). Up to 28% of the aged DDT residues were released from the soils by Tenax over a 24-h extraction period. Significant relationships (p < 0.01) between the Tenax-extractable and earthworm tissue concentrations for p,p′-DDE and p,p′-DDT showed that Tenax provides a good surrogate measure of the bioavailability of these compounds to A. caliginosa. Surprisingly, there was a similarly significant relationship (p < 0.001) between the total soil and earthworm tissue concentrations for p,p′-DDE and p,p′-DDT, suggesting that total soil concentrations alone were sufficient to predict uptake by A. caliginosa. These results demonstrate that the aged agrichemical residues in orchard soils, and particularly p,p′-DDE and p,p′-DDT, remain highly bioavailable to A. caliginosa despite decades of weathering and continue to present an environmental risk

year: 2012

title: Pragmatic internet egress routing for improving player latency in interactive multiplayer games

authors: Fayomi, Oladimeji

subjects: Latency-aware routing

abstract: Interactive multiplayer games rely on the network to ensure a smooth and
responsive experience. When the latency between a game server and a client
is beyond a threshold, the client is unable to play the game properly and often
abandons the game. We posit that this unfortunate disconnection is avoidable
in certain cases. Because Border Gateway Protocol (BGP) is agnostic to
latency, the paths used by clients may be suboptimal latency-wise. Providing
performance-aware routing on the Internet in general is a hard problem, and
proposals to change BGP or the core of the Internet struggled to gain traction.
However, Multiplayer games provide a workable problem: it may be possible to
attain feasible (i.e., sufficiently low) latency for players without major changes
to the Internet core.

This thesis presents a pragmatic latency-aware routing control approach
which tackles interactive multiplayer games and other applications that need to
operate under some specific latency threshold but are not bandwidth-hungry.
The proposed approach – Overwatch, leverages BGP Egress Peer Engineering
(EPE) and capitalises on the well-connected nature of game provider networks
to offer multiple paths to reach their clients. By selecting a feasible path
for each client, Overwatch can maximise the number of clients/players in the
game. One of the key advantages of Overwatch is its deployability, which is
enabled by its explicit routing feature using commodity hardware, which is
interoperable with existing devices and does not require collaboration with
other networks. Overwatch controls traffic along feasible paths according to
an operator-defined algorithm. The current implementation is based on a
Segment Routing over IPv6 (SRv6) dataplane. This implementation was used
to evaluate Overwatch in a scenario with 300 clients. Prior to that, we ran
a set of Internet measurements involving relevant game servers in Europe to
calibrate the experiments. The evaluation highlights Overwatch’s benefit in
selecting feasible paths for the players when such paths exist, thus keeping
players online.

text: Pragmatic internet egress routing for improving player latency in interactive multiplayer games Interactive multiplayer games rely on the network to ensure a smooth and
responsive experience. When the latency between a game server and a client
is beyond a threshold, the client is unable to play the game properly and often
abandons the game. We posit that this unfortunate disconnection is avoidable
in certain cases. Because Border Gateway Protocol (BGP) is agnostic to
latency, the paths used by clients may be suboptimal latency-wise. Providing
performance-aware routing on the Internet in general is a hard problem, and
proposals to change BGP or the core of the Internet struggled to gain traction.
However, Multiplayer games provide a workable problem: it may be possible to
attain feasible (i.e., sufficiently low) latency for players without major changes
to the Internet core.

This thesis presents a pragmatic latency-aware routing control approach
which tackles interactive multiplayer games and other applications that need to
operate under some specific latency threshold but are not bandwidth-hungry.
The proposed approach – Overwatch, leverages BGP Egress Peer Engineering
(EPE) and capitalises on the well-connected nature of game provider networks
to offer multiple paths to reach their clients. By selecting a feasible path
for each client, Overwatch can maximise the number of clients/players in the
game. One of the key advantages of Overwatch is its deployability, which is
enabled by its explicit routing feature using commodity hardware, which is
interoperable with existing devices and does not require collaboration with
other networks. Overwatch controls traffic along feasible paths according to
an operator-defined algorithm. The current implementation is based on a
Segment Routing over IPv6 (SRv6) dataplane. This implementation was used
to evaluate Overwatch in a scenario with 300 clients. Prior to that, we ran
a set of Internet measurements involving relevant game servers in Europe to
calibrate the experiments. The evaluation highlights Overwatch’s benefit in
selecting feasible paths for the players when such paths exist, thus keeping
players online.

year: 2024

title: Paremias xeocosmolóxicas de predición do tempo en galego e maorí (Geocosmologic paroemias of weather prediction in Galician and Maori)

authors: Lopez-Fernandez, Laura

abstract: This comparative study collects phraseological units -dictons- (Rodegem 1984 e Sevilla Muñoz 1988; 1992) related to the semantic field of weather forecast from two cultures, which have not been in contact, and which are located in the antipodes of the planet: Galician and Maori. The methodology used utilizes a diachronic analysis (although not diastratic), of geocosmological proverbs, that can be or not in use nowadays, which include dictons about atmospheric phenomena, observation of the stars and star lore, and weather forecast through observation of animals, especially birds. The dictons collected in Maori do not come from informants but from the few books and digital sources available at the moment and this represents only a fragment of their traditional oral culture, thought and legacy of the different iwis. The collected dictons in Galician have been collected from a variety of digital corpus and resources.

text: Paremias xeocosmolóxicas de predición do tempo en galego e maorí (Geocosmologic paroemias of weather prediction in Galician and Maori) This comparative study collects phraseological units -dictons- (Rodegem 1984 e Sevilla Muñoz 1988; 1992) related to the semantic field of weather forecast from two cultures, which have not been in contact, and which are located in the antipodes of the planet: Galician and Maori. The methodology used utilizes a diachronic analysis (although not diastratic), of geocosmological proverbs, that can be or not in use nowadays, which include dictons about atmospheric phenomena, observation of the stars and star lore, and weather forecast through observation of animals, especially birds. The dictons collected in Maori do not come from informants but from the few books and digital sources available at the moment and this represents only a fragment of their traditional oral culture, thought and legacy of the different iwis. The collected dictons in Galician have been collected from a variety of digital corpus and resources.

year: 2015