One of the many theories about alcoholism is the learning and reinforcement theory, which explains alcoholism by considering alcohol ingestion as a reflex response to some stimulus and as a way to reduce an inner drive state such as fear or anxiety. Characterizing life situations in terms of approach and avoidance, this theory holds that persons tend to be drawn to pleasant situations or repelled by unpleasant ones. In the latter case, alcohol ingestion is said to reduce the tension or feelings of unpleasantness and to replace them with the feeling of euphoria generally observed in most persons after they have consumed one or more drinks. Some experimental evidence tends to show that alcohol reduces fear in an approach-avoidance situation. Conger trained one group of rats to approach a food goal and, using aversive conditioning, trained another group to avoid electric shock. After an injection of alcohol the pull away from the shock was measurably weaker, while the pull toward the food was unchanged. The obvious troubles experienced by alcoholic persons appear to contradict the learning theory in the explanation of alcoholism. The discomfort, pain, and punishment they experience should presumably serve as a deterrent to drinking. The fact that alcoholic persons continue to drink in the face of family discord, loss of employment, illness, and other sequels of repeated bouts is explained by the proximity of the drive reduction to the consumption of alcohol; that is, alcohol has the immediate effect of reducing tension while the unpleasant consequences of drunken behavior come only later. The learning paradigm, therefore, favors the establishment and repetition of the resort to alcohol. In fact, the anxieties and feelings of guilt induced by the consequences of excessive alcohol ingestion may themselves become the signal for another bout of alcohol abuse. The way in which the clue for another bout could be the anxiety itself is explained by the process of stimulus generalization, conditions Or events occurring at the time of reinforcement tend to acquire the characteristics of stimuli. When alcohol is consumed in association with a state of anxiety or fear, the emotional state itself takes on the properties of a stimulus, thus triggering another drinking bout. The role of punishment is becoming increasingly important in formulating a cause of alcoholism based on the principles of learning theory. While punishment may serve to suppress a response, experiments have shown that in some cases it can serve as a reward and reinforce the behavior. Thus if the alcoholic person has learned to drink under conditions of both reward and punishment, either type of condition may precipitate renewed drinking. Ample experimental evidence supports the hypothesis that excessive alcohol consumption can be learned. By gradually increasing the concentration of alcohol in drinking water, psychologists have been able to induce the ingestion of larger amounts of alcohol by an animal than would be normally consumed. Other researchers have been able to achieve similar results by varying the schedule of reinforcement; that is, by requiring the animal to consume larger and larger amounts of the alcohol solutions before rewarding it. In this manner, animals learn to drink enough to become dependent on alcohol in terms of demonstrating withdrawal symptoms. Which of the following, according to the passage, contribute(s) to alcoholism Ⅰ. the need to reduce tensions and anxieties Ⅱ. the anxieties resulting from guilt feelings about previous drinking bouts Ⅲ. punishment for alcoholic behavior
A. Ⅰ only
B. Ⅰ and Ⅱ only
C. Ⅰ, Ⅱ, and Ⅲ
D. Ⅱ and Ⅲ only
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Malnutrition during weaning age—when breast milk is being replaced by semi-solid foods—is highly prevalent in children of poor households in many developing countries. While the etiology (病因学) is complex and multifactorial, the immediate causes are recognized as feeding at less than adequate levels for child growth and development, and recurrent infections, including diarrhea, resulting mainly from ingestion of contaminated foods. As a result, many young children, particularly between six months to two years of age, experience weight loss and impaired growth and development. Studies by investigators in various countries have concentrated on traditional food preparation methods and have resulted in offering cheap and practical answers to these problems based on familiar, indigenous and culturally acceptable home processing practices. Two such answers have arisen. Firstly, cereal fermentation is used for reducing the risk of contamination under the existing inappropriate conditions for food preparation and storage in many households. Secondly, a tiny amount of sprouted grains flour is used in preparation of weaning foods as a magic way to lessen the viscosity without decreasing energy density. Anti-microbial substances in fermented foods cause acidity.
A method to eliminate pathogenic (致病的) bacteria and inhibit their growth during storage of weaning preparations can benefit nutrition and health in young children considerably. Use of fermented foods for feeding children of weaning age appears to be an effective solution. Fermented foods have lower levels of diarrhoeal germ contamination, they are suitable for child feeding, and can be safely stored for much longer periods of time than fresh foods. The practice has been a traditional way of food preservation in many parts of the world. The anti-microbial properties of fermented foods and their relative higher safety—documented since the early 1900’s—have been indicated in a number of studies.
B. In Ghana, it is common to ferment maize dough before cooking it as porridge. In Kenya, cereal-based porridge and milk are traditionally fermented. Preserving milk in the form of yogurt has been known to many households living in hot climate.
C. What are the underlying mechanisms by which fermentation processes help to prevent or reduce contamination A possible answer suggests that during the fermentation process foods become more acid. This explains why diarrhea-causing bacteria are not able to grow in fermented foods as rapidly as in unfermented ones. It is also hypothesized that some of the germs present in the foods are killed or inhibited from growing through the action of antimicrobial substances produced during fermentation. The fermented foods can, therefore, be kept for a longer time compared to fresh ones. It has been shown that while contamination levels in cooked unfermented foods increase with storage time, fermented foods remain less contaminated.
D. Whatever the underlying mechanisms, the fact is that the exercise reduces contamination without adding to the household cost both in terms of time and money. Its preparation is easy. The cereal flour is mixed with water to form a dough which is left to be fermented; addition of yeast (酵母), or mixing with a small portion of previously fermented dough is sometimes needed. The dough can then be cooked into porridge for feeding to the child.Although beneficial, unfortunately the practice is going out of fashion, partly because of current emphasis on the use of fresh foods, particularly for children. For example, a study on the use of fermented foods for young children in Kenya, demonstrated that while foods are still frequently fermented at home for child feeding, their use is becoming less popular, particularly in urban area where commercial products are more available. Clearly they now need to be promoted.
E. Directions:
F. The statements below relate to the passage you have just read. Identify whether they are TRUE or FALSE and mark the corresponding letter (T for True and F for False) on the Answer Sheet with a single line through the center.
根据所给情景,用英语写一张50字左右的便条。 李大为告诉王东,他要请王东去听音乐会,但把票忘在书桌上了。他急着回去拿票。叫王东先去,一小时后在剧院门口等他。
请根据下面短文回答第66~70题: Mr. Zhang is touring in a foreign country, and this is the room card of the hotel he is living in. (作图) Mr. Zhang lives in ______。
以中药材为原料,在中医药理论指导下,按规定的处方和制法大量生产,有特有名称并标明功能主治、用法用量和规格的药品()
A. 药品
B. 药物
C. 剂型
D. 中成药
E. 制剂