TASK DEFINITION: Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
PROBLEM: TransLink is urging customers to avoid non-essential travel today and to stay home where possible in the difficult weather conditions. TransLink chief executive officer Peter Strachan said bus and train services were continuing to run where possible, however all CityCat and CityFerry services had been cancelled until further notice. "These are extremely difficult conditions for South East Queensland---we are running essential services where possible but safety remains to be the most important," Mr Strachan said. "Severe weather and associated flooding has impacted on all modes of public transport, with bus, ferry and train services all impacted to varying degrees. "If you are planning to use public transport at anytime over the next few days, then I would recommend you check that your intended service is still running." Service disruptions for today include: l City network trains running hourly on all lines. l Bus diversions, delays and cancellations in some regions, particularly across Brisbane, Ipswich and the Sunshine Coast. l CityCat and CityFerry services cancelled. Queensland Rail Chief Executive Officer Paul Scurrah said rising waterways had closed some train lines, and road closures and damage to property throughout the South-East had contributed to a shortage of available rail employees. "We intend to run trains hourly on all lines, similar to the timetable we operate on Christmas Day. We will also be looking to run other additional services to meet demand as required. At this stage we will run services stopping at all stations which will depart at the same time on the hour, however, this is all subject to the weather conditions and the availability of traincrew." Mr Scurrah encouraged all customers to visit the Translink website for specific departure times for their station, and asked for patience in the event of delays. "Queensland Rail appreciates that reduced services may cause disruptions but it is simply unavoidable. We have a dedicated and experienced team monitoring the situation around the clock and will be working to reopen the network as soon as practicably possible," Mr Scurrah said. The latest service disruption information is available on the TransLink website www.translink.com.au.

SOLUTION: Which means of transport is NOT available during the special period?

PROBLEM: Humans use six times as much water today as they did 100 years ago. People living in developed countries use a far greater proportion of the worlds water than people in less developed countries. What do people use all of that water for? Besides drinking and washing, people need water for agriculture, industry, household uses, and recreation (Figure Water use can be consumptive or non-consumptive, depending on whether the water is lost to the ecosystem. Non-consumptive water use includes water that can be recycled and reused. For example, the water that goes down the drain and enters the sewer system is purified and then redistributed for reuse. By recycling water, the overall water consumption is reduced. Consumptive water use takes the water out of the ecosystem. Can you name some examples of consumptive water use? Some of the worlds farmers still farm without irrigation by choosing crops that match the amount of rain that falls in their area. But some years are wet and others are dry. For farmers to avoid years in which they produce little or no food, many of the worlds crops are produced using irrigation. Water used for home, industrial, and agricultural purposes in different regions. Globally more than two-thirds of water is for agriculture. Three popular irrigation methods are: Overhead sprinklers. Trench irrigation: canals carry water from a water source to the fields. Flood irrigation: fields are flooded with water. All of these methods waste water. Between 15% and 36% percent of the water never reaches the crops because it evaporates or leaves the fields as runoff. Water that runs off a field often takes valuable soil with it. A much more efficient way to water crops is drip irrigation (Figure 1.2). With drip irrigation, pipes and tubes deliver small amounts of water directly to the soil at the roots of each plant or tree. The water is not sprayed into the air or over the ground, so nearly all of it goes directly into the soil and plant roots. Why do farmers use wasteful irrigation methods when water-efficient methods are available? Many farmers and farming corporations have not switched to more efficient irrigation methods for two reasons: 1. Drip irrigation and other more efficient irrigation methods are more expensive than sprinklers, trenches, and flooding. 2. In the United States and some other countries, the government pays for much of the cost of the water that is used for agriculture. Because farmers do not pay the full cost of their water use, they do not have any financial incentive to use less water. What ideas can you come up with to encourage farmers to use more efficient irrigation systems? Aquaculture is a different type of agriculture. Aquaculture is farming to raise fish, shellfish, algae, or aquatic plants (Figure 1.3). As the supplies of fish from lakes, rivers, and the oceans dwindle, people are getting more fish from aquaculture. Raising fish increases our food resources and is especially valuable where protein sources are limited. Farmed fish are becoming increasingly common in grocery stores all over the world. Workers at a fish farm harvest fish they will sell to stores. Growing fish in a large scale requires that the fish stocks are healthy and protected from predators. The species raised must be hearty, inexpensive to feed, and able to reproduce in captivity. Wastes must be flushed out to keep animals healthy. Raising shellfish at farms can also be successful. For some species, aquaculture is very successful and environmental harm is minimal. But for other species, aqua- culture can cause problems. Natural landscapes, such as mangroves, which are rich ecosystems and also protect coastlines from storm damage, may be lost to fish farms (Figure 1.4). For fish farmers, keeping costs down may be a problem since coastal land may be expensive and labor costs may be high. Large predatory fish at the 4th or 5th trophic level must eat a lot, so feeding large numbers of these fish is expensive and environmentally costly. Farmed fish are genetically different from wild stocks, and if they escape into the wild they may cause problems for native fish. Because the organisms live so close together

SOLUTION: water that can be recycled and reused is called ____________water use.

PROBLEM: Spectrins comprise - and -subunits made up predominantly of a series of homologous repeating units of about 106 amino acids; the - and -chains form antiparallel dimers by lateral association, and tetramers through head-to-head contacts between the dimers. Here we consider the first of these interactions. (1) We confirm earlier observations, showing that the first two paired repeats (IR1 with IR21, and IR2 with RI20) at one end of the erythroid spectrin (II) dimer are necessary and sufficient to unite the chains; (2) we resolve a conflict in published reports by showing that the strength of the interaction is considerably increased on adding the adjoining pair of repeats (IR3-IR19); (3) in brain (IIII) spectrin the first two pairs of repeats are similarly essential and sufficient for heterodimer formation; (4) this interaction is ~60-fold stronger than that in the erythroid counterpart, but no enhancement can be detected on addition of three further pairs of repeats; (5) formation of a tight II dimer probably depends on structural coupling of the first two repeats in each chain; (6) an analysis of the sequences of the strongly interacting repeats, IR1, IIR1, IR21 and IIR20 and repeats in -actinin, which also interact very strongly in forming an antiparallel dimer, affords a possible explanation for the different properties of the two spectrin isoforms in respect of the stability of the inter-chain interactions, and also suggests the evolutionary path by which the erythroid and non-erythroid sequences diverged.

SOLUTION:
Alpha-spectrin and beta-spectrin subunits form parallel or antiparallel heterodimers?