Small Amounts Of Food Research Articles

Immunization with DAT fragments is associated with long-term striatal impairment, hyperactivity and reduced cognitive flexibility in mice

BackgroundPossible interactions between nervous and immune systems in neuro-psychiatric disorders remain elusive. Levels of brain dopamine transporter (DAT) have been implicated in several impulse-control disorders, like attention deficit / hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). Here, we assessed the interplay between DAT auto-immunity and behavioural / neurochemical phenotype.MethodsMale CD-1 mice were immunized with DAT peptide fragments (DAT-i), or vehicle alone (VEH), to generate elevated circulating levels of DAT auto-antibodies (aAbs). Using an operant delay-of-reward task (20 min daily sessions; timeout 25 sec), mice had a choice between either an immediate small amount of food (SS), or a larger amount of food after a delay (LL), which increased progressively across sessions (from 0 to 150 sec).ResultsDAT-i mice exhibited spontaneous hyperactivity (2 h-longer wake-up peak; a wake-up attempt during rest). Two sub-populations differing in behavioural flexibility were identified in the VEH control group: they showed either a clear-cut decision to select LL or clear-cut shifting towards SS, as expected. Compared to VEH controls, choice-behaviour profile of DAT-i mice was markedly disturbed, together with long-lasting alterations of the striatal monoamines. Enhanced levels of DA metabolite HVA in DAT-i mice came along with slower acquisition of basal preferences and with impaired shifting; elevation also in DOPAC levels was associated with incapacity to change a rigid selection strategy. This scarce flexibility of performance is indicative of a poor adaptation to task contingencies.ConclusionsHyperactivity and reduced cognitive flexibility are patterns of behaviour consistent with enduring functional impairment of striatal regions. It is yet unclear how anti-DAT antibodies could enter or otherwise affect these brain areas, and which alterations in DAT activity exactly occurred after immunization. Present neuro-behavioural alterations, coming along with an experimentally-induced rise of circulating DAT-directed aAbs, open the issue of a potential role for auto-immunity in vulnerability to impulse-control disorders.

A fruit in hand is worth many more in the bush: Steep spatial discounting by free-ranging rhesus macaques (Macaca mulatta)

Decision making is one of the principal cognitive processes underlying goal-directed behaviour and thus there is justifiably strong interest in modeling it. However, many of these models have yet to be tested outside of the laboratory. At the same time, field work would benefit from the use of experimental methods developed in the laboratory to determine the causal relationships between environmental variables and behaviour. We therefore adapted a laboratory-derived experimental paradigm to test decision making in the wild. The experiment used an indifference-point procedure to determine the influence of both the amount and distance of food on choice behaviour. Free-ranging rhesus monkeys were given the choice between a smaller amount of food at a closer distance and a larger amount farther away. In four conditions, we held the closer amount constant across trials and varied the farther amount to determine the point at which the monkeys were indifferent to the choice alternatives. For example, in condition one, we used one piece of food at the closer location, and determined how many pieces would be equivalent in the farther location. Four different closer amounts were tested to obtain an indifference point curve, with the indifference amounts at the farther location plotted against the closer amounts. The slope of the obtained linear indifference curve was surprisingly high, suggesting that rhesus monkeys significantly discount food that is farther away. Possible reasons for this steep spatial discounting are discussed.

Tracking of food quantity by coyotes (Canis latrans)

Previous studies have demonstrated that Weber's Law mediates quantitative discrimination abilities across various species. Here, we tested coyotes' (Canis latrans) ability to discriminate between various quantities of food and investigated whether this ability conforms to predictions of Weber's Law. We demonstrate herein that coyotes are capable of reliably discriminating large versus small quantities of discrete food items. As predicted by Weber's Law, coyotes' quantitative discrimination abilities are mediated by the ratio between the large and small quantities of food and exhibit scalar variability. Furthermore, in this task coyotes were not discriminating large versus small quantities based on olfactory cues alone.

The importance of being weaned: From guidelines to practice

The appropriate time to wean is a topic of hot debate and mothers are left with the dilemma of when it is actually best to introduce their child to solid foods. But, as Professor Marion Hetherington, University of Leeds, asks: who is right? Introducing complementary foods to an infant is an important stage of their life. Mothers regard this time as a special milestone, a time to celebrate and a key stage in their child's growing up. This transition marks the beginning of the baby's readiness to join the family at mealtimes and to share in the same foods. Mothers are encouraged to enjoy this process, not to rush it and to respond to the needs of their babies. Parents are offered guidance on when, what and how to wean. However, advice has changed over the past decade and there has been some confusion, especially when maternal experience conflicts with government guidelines. What happens, for example, when heavyweights such as the World Health Organization (WHO) or trusted community-based health professionals suggest that babies should be weaned no earlier than six months but mothers are faced with a hungry, irritable four month old? Do mothers wait until that critical age to offer solid foods or do they know best for their own baby? It would seem that despite changes to the guidance on solid food introduction, most mothers do not follow recommendations, with as few as 1% of British mothers weaning at or after six months.1 Guidance about when to introduce complementary foods to the infant diet is critically important but advice to mothers can vary across countries, perhaps reflecting cultural differences in the methods and timing of this process. Mothers want the best for their babies, but what is best and what is the evidence for the optimal time to wean? Who knows best WHO? The WHO has over the past decade advocated that infants should be breastfed exclusively for six months.2 The first of its guiding principles for the introduction of complementary feeding for breastfed infants states that one should: 'Start at six months of age with small amounts of food and increase the quantity as the child gets older, while maintaining frequent breastfeeding.'2 Undoubtedly, exclusive breastfeeding for at least four months provides the best start in life, with considerable health advantages, including significantly improved developmental outcomes. What has been in doubt and the topic of considerable debate is the optimal duration of exclusive breastfeeding to provide the greatest benefit against the potential risks, specifically within the developed world. Articles challenging the WHO's recommendation for exclusive breastfeeding for the first six months do so on many different levels: the quality and relevance of the evidence underlying the recommendation for developed countries, 3 the potential energy gap between infant requirements and energy transfer from the mother,4 the risk of iron deficiency,5 and the pragmatic view that fewer than an estimated 35% of mothers worldwide follow the guidance to breastfeed exclusively for six months (WHO 2009 communications). Following these challenges, the WHO has been moved to respond through its communications arm to defend its guidance, stating: WHO recommends mothers worldwide to exclusively breastfeed infants for the child's first six months to achieve optimal growth, development and health. Thereafter, they should be given nutritious complementary foods and continue breastfeeding up to the age of two years or beyond.6 Early weaning Clearly, mothers are being encouraged to introduce complementary foods at six months but in responding to their baby's needs may wish to do this sooner. However, early weaning (before four months) is linked to health problems such as wheeze and diarrhoea and it may also be linked to poorer energy regulation and more rapid weight gain. Early weaning is associated with a significantly increased risk of obesity by the age of three years and this effect can be independent of rapid infant weight gain. …

P3-S1.18 Side effects of doxycycline in adolescents treated for pelvic inflammatory disease

BackgroundOur purpose was to assess adverse reactions to doxycline in adolescents under treatment for PID.MethodsAt the Harris County (Houston), Texas, USA Juvenile Detention Center from May 2008 through January 2010,...

Using judgement bias to measure positive affective state in dogs

Interest in the induction and measurement of positive affective states in non-human animals is increasing. Here, we used a test of cognitive (judgement) bias, based on the finding that individuals experiencing different affective states judge ambiguous stimuli differently, to measure whether a positive low arousal affective state (e.g. ‘satisfaction’/‘contentment’) could be induced in domestic dogs as a result of their experiencing a food-based rewarding event. In this rewarding event, subjects (1 year old female Beagles) had to search for small amounts of food randomly placed within a maze arena. Using a balanced within-subjects design, the dogs ( N = 12) received a cognitive bias test either without experiencing the rewarding event (the ‘Neutral’ treatment), or directly after experiencing the rewarding event (the ‘Post-consumption’ treatment). In the test, dogs were trained that one visual cue (e.g. dark grey card) predicted a positive event (food in a bowl) whilst a different cue (e.g. light grey card) predicted a relatively ‘negative’ event (empty bowl). We hypothesised that dogs tested after experiencing the rewarding event, and in a presumed post-consummatory positive affective state, would be more likely to judge visually ambiguous stimuli (intermediate grey cards) positively, compared to dogs in the ‘Neutral’ treatment. In contrast, we found that they took significantly longer to approach an intermediate ambiguous stimulus, suggesting that they were less likely to anticipate food (a negative judgement) compared to dogs in the ‘Neutral’ treatment group. Various explanations for the observed results are discussed, in particular how reward acquisition and consumption may influence positive affective state induction in animals.

Can lemurs (Eulemur fulvus and E. macaco) use abstract representations of quantities to master the reverse-reward contingency task?

In previous studies we demonstrated that brown and black lemurs (Eulemur fulvus and E.macaco) showed self-control abilities under a reverse-reward contingency. They were able to significantly select the smaller quantity of food to be rewarded with the larger one and to generalize this ability when presented with two rewards that differed in quality. In the present study, previously trained subjects had to choose between graphic representations of two different quantities of food under the reverse-reward contingency. Three out of four subjects learned to associate a graphic representation of the reward with the corresponding quantity. Only one subject consistently selected the representation of the smaller quantity to be rewarded with the larger quantity of food and therefore showed abstraction as well as relative numerousness skills. Indeed, she was able to discriminate between representations of different quantities and to ordinate them. We discuss how primates mentally represent food quantities and how self-control is involved in foraging strategies.

EXTENDED PAUSING BY HUMANS ON MULTIPLE FIXED-RATIO SCHEDULES WITH VARIED REINFORCER MAGNITUDE AND RESPONSE REQUIREMENTS

We conducted three experiments to reproduce and extend Perone and Courtney's (1992) study of pausing at the beginning of fixed-ratio schedules. In a multiple schedule with unequal amounts of food across two components, they found that pigeons paused longest in the component associated with the smaller amount of food (the lean component), but only when it was preceded by the rich component. In our studies, adults with mild intellectual disabilities responded on a touch-sensitive computer monitor to produce money. In Experiment 1, the multiple-schedule components differed in both response requirement and reinforcer magnitude (i.e., the rich component required fewer responses and produced more money than the lean component). Effects shown with pigeons were reproduced in all 7 participants. In Experiment 2, we removed the stimuli that signaled the two schedule components, and participants' extended pausing was eliminated. In Experiment 3, to assess sensitivity to reinforcer magnitude versus fixed-ratio size, we presented conditions with equal ratio sizes but disparate magnitudes and conditions with equal magnitudes but disparate ratio sizes. Sensitivity to these manipulations was idiosyncratic. The present experiments obtained schedule control in verbally competent human participants and, despite procedural differences, we reproduced findings with animal participants. We showed that pausing is jointly determined by past conditions of reinforcement and stimuli correlated with upcoming conditions.

Food Allergy & Asthma Redux

Source: Liu AH, Jaramillo R, Sicherer S, et al. National prevalence and risk factors for food allergy and relationship to asthma: results from the National Health and Nutrition Examination Survey 2005–2008. J Allergy Clin Immunol. 2010; 126(4): 798– 806; doi: 10.1016/j.jaci.2010.07.026Investigators from multiple institutions reviewed data from the 2005–2006 National Health and Nutrition Examination Survey (NHANES) to estimate the rates of food allergy (FA) in the United States, identify populations at high risk for FA, and explore the associations with other atopic conditions. Serum specific IgE food panels (peanut, cow’s milk, egg white, and shrimp) were obtained on 79.3% of the 10,348 participants. Based on specific cut-offs for IgE levels against each food, participants were classified as having unlikely FA, possible FA, or likely FA. Clinical FA rates were estimated by summing 50% of the number of participants with possible FA and 95% of those with likely FA. A classification of “sensitization” was made in study participants who had an IgE level above the lower limit of detection for at least one food allergen. Participants were considered to have other atopic conditions, including asthma, hay fever, and eczema, based on self-report and doctor-confirmed diagnoses. Both the sampling and analytical methodologies were designed to provide nationally representative estimates.Among the diverse group of study participants, allergic sensitization to at least one food allergen was identified in 16.8% of those enrolled. The rate of asthma in the study population was 14.6%, hay fever 10.8%, and eczema 9.1%. The overall national prevalence of clinical FA was estimated to be 2.5%; estimates for clinical FA to milk, egg, and peanuts were 0.4%, 0.23%, and 1.3%, respectively. Rates of clinical FA were highest in children aged 1 to 5 years, at 4.2%, and lowest in adults over 60, at 1.3%. The prevalence of clinical FA to milk, eggs, and peanut were each about 1.8% in children aged 1 to 5 years, while the rates of peanut allergies were highest in children aged 6 to 19, at 10.7%. Rates of allergy to multiple foods were highest in children aged 1 to 5 years, at 0.4%.The risk of possible or likely FA was increased in non-Hispanic blacks (OR=3.06; 95% CI, 2.14–4.36), males (OR=1.87; 95% CI, 1.32–2.16), and children (OR=2.04; 95% CI, 1.42–2.93). Study participants with doctor-diagnosed asthma also had increased risk of food sensitization. Those with likely FA had an adjusted OR for current asthma of 3.8 (95% CI, 1.5–10.7); emergency department visits for asthma were notably increased in those with likely FA (OR=6.9; 95% CI, 2.4–19.7). In general, FA was more prevalent in individuals living in poverty and least prevalent in those with higher household incomes. The authors postulate that unrecognized FA may contribute to the severity of asthma.Dr Nimmagadda has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.FA prevalence has been rising in the United States over the past decade. Substantial increases in peanut and tree nut allergy have been well documented during this time period.1 Specific risk factors for the development of FA have not been well established. The results of the current study reinforce the concept that male subjects and children are at highest risk for the development of FA. Surprisingly, an increased risk was found in non-Hispanic black individuals as well.Associations between atopic dermatitis and FA have been well established.2,3 However, the association with the development of asthma in children with FA has only recently been documented. The asthma predictive risk index has included FA as a risk factor for the development of asthma in wheezing children younger than 3 years of age.4The authors of this study also point out that the presence of FA may potentially increase asthma severity. Foods in general were not thought to contribute to asthma exacerbations. However, they may play a larger role than previously thought.Asthma is present in nearly all subjects who have fatal anaphylactic reactions to food exposure.5 In food-allergic children with worsening asthma symptoms, the exposure to small amounts of foods can increase bronchial hyperreactivity without inducing bronchospasm.6 Thus, pediatricians should be aware of worsening asthma symptoms in food-allergic children despite adequate asthma therapy. Reinforcing food avoidance should be undertaken at each visit in children with both FA and asthma.

Feeding ecology of Pachyurus bonariensis Steindachner, 1879 (Sciaenidae: Perciformes) in the Ibicuí River, Southern Brazil: ontogenetic, seasonal and spatial variations

Knowledge of the feeding ecology of fish is essential for understanding the functioning of freshwater communities. Here we report on an analysis of the diet of Pachyurus bonariensis Steindachner, 1879, a freshwater sciaenid. Fish were collected bimonthly from December 1999 to January 2002 at three locations along the Ibicuí River in the Rio Grande do Sul State, Brazil. At each location, the specimens were collected in both lentic and lotic environments. The stomachs of 324 fish were analysed for contents and fullness. The main items were Ephemeroptera, Diptera (larvae), Trichoptera and Odonata. Annelida, plant matter, Decapoda, Diptera (pupae), Coleoptera and Mollusca were present in small amounts. The fish consumed smaller amounts of food in winter than in other seasons. The most important source of dietary variation for P. bonariensis was the ontogenetic, related to intrinsic biological characters. However, spatial variation was also found, suggesting that this species can adapt its diet to environmental changes. Although P. bonariensis showed ontogenetic and spatial variations in the main items consumed, the main items were always insects, characterising P. bonariensis as a fish with an insectivorous feeding habit in the Ibicuí River.

Are dogs (Canis familiaris) misled more by their owners than by strangers in a food choice task?

Dogs are highly skilled in understanding a large variety of human social cues and use them appropriately to solve a number of different cognitive tasks. They rely on human signals even when these are contradictory or misleading and ultimately prevent them from correctly solving a task. In the following two experiments, we investigated whether the owner and a stranger differently influenced dogs' choices in food discrimination tasks. In Experiment 1, 48 dogs were tested in 3 different conditions: (1) choice between a large and a small amount of dog pellets with no demonstration; (2) choice between a large and a small amount of dog pellets after having witnessed the owner/stranger favouring the small quantity; (3) choice between two single food pellets after observing the owner/stranger choosing one of them. In Experiment 2, 48 dogs could choose between two foods of different palatability: in Condition1, dogs chose between a slice of sausage and a dry pellet with no demonstration. In Condition2, the same choice was available but with a person (owner/stranger) showing a preference for the dry pellet. In Condition3, dogs chose between a single dry pellet and 8 slices of sausage, with the person (owner/stranger) showing a preference for the pellet. In both experiments, dogs conformed to the human's indications even though these led to the selection of the less advantageous option (i.e. the smaller amount of food in Experiment 1 or the low quality food in Experiment 2). However, the owner and the stranger did not differently influence the dogs' behaviour. Results show that dogs are willing to follow a person's indication even when this is visibly (if perhaps only mildly) counterproductive to them and that they are socially prepared to rely equally on cues given by the owner and an unfamiliar friendly person.

Food and Levothyroxine Administration in Infants and Children

Administer tablets and capsules with water on an empty stomach, preferably one-half hour to an hour before breakfast. Administer four hours apart from antacids, iron, and calcium supplements (Prod Info Tirosint oral capsules, 2006; Prod Info Synthroid oral tablets, 2005; Prod Info Levoxyl oral tablets, 2004). Levothyroxine tablets may be crushed and suspended in 5 to 10 milliliters of water prior to administration. The suspension should be given immediately by a spoon or dropper. The crushed tablet may also be sprinkled over a small amount of food (applesauce or cooked cereal). Foods containing large amounts of soybean, fiber, or iron should not be used for administering levothyroxine (Prod Info Synthroid oral tablets, 2005).

Finding Inspiration and a Profession

You have accessThe ASHA LeaderFirst Person on the Last Page1 Apr 2010Finding Inspiration and a ProfessionFirst Person on the Last Page Yael Lefkowitz Yael Lefkowitz Google Scholar More articles by this author https://doi.org/10.1044/leader.FPLP.15042010.39 SectionsAbout ToolsAdd to favorites ShareFacebookTwitterLinked In I hope to become a speech-language pathologist—a decision that was validated last summer when I volunteered at a rehab hospital and nursing home, not realizing that this experience would influence the direction of my future career. Although I am not a morning person, I practically jumped out of bed each day to get to the hospital and wished that there were more hours in the workday. I observed everything from swallow evaluations to treatment sessions for Parkinson’s disease to stroke support groups. I also made numerous visits to the amyotrophic lateral sclerosis (ALS) clinic. Everyone, from the clinicians around me to the patients, was so inspiring and enlightening that each day was more exciting than the next. When I walked into the room of a long-term care patient to observe a swallow evaluation with a clinician, I saw a woman who appeared to be wilting away, yet the clinicians would not give up on her. She had a PEG tube, but SLPs wanted to determine if she could withstand even a small amount of food by mouth so that she would feel more alive during her last days. I expected the ALS clinic visits would be difficult emotionally, yet I found myself looking forward to them. The patients with ALS are some of the strongest and most determined people I have ever met. Walking into the exam rooms, I envisioned being an inspiration to these patients—but I was mistaken. Instead, they were my inspiration. One patient was a middle-aged woman who looked stunning with her perfectly done makeup, beautiful hair, and stylish outfit. The wheelchair and her partially paralyzed hands were the only clues to the disease. She refused to give up and was determined not to let ALS rob her dignity. These patients had a tremendous impact on my life, and someday I hope that I might influence theirs. One of the first patients with ALS that I visited kept asking questions about my life and my plans for the future. In responding, I asked myself the same questions about his life. What were his plans for the future? With the progression of his disease, I knew he would be lucky to attend his daughter’s next birthday. Yet, he still cared to ask about my aspirations. His selfless interest taught me never to compare my situation with others. These patients taught me how to truly appreciate the gift of speech—sometimes without saying a word—and as an SLP, I will do everything possible to impart this gift to as many as I can. Author Notes Yael Lefkowitz, is a senior at Stern College for Women in New York City. She hopes to attend graduate school in the New York area in fall 2010 and then to work in a hospital setting. Contact her at [email protected] Advertising Disclaimer | Advertise With Us Advertising Disclaimer | Advertise With Us Additional Resources FiguresSourcesRelatedDetails Volume 15Issue 4April 2010 Get Permissions Add to your Mendeley library History Published in print: Apr 1, 2010 Metrics Downloaded 312 times Topicsasha-topicsleader_do_tagleader-topicsasha-article-typesCopyright & Permissions© 2010 American Speech-Language-Hearing AssociationLoading ...

Nutrition in vulnerable communities in economically marginalized societies

Childhood malnutrition is highly prevalent in developing countries. Globally 35% (3.5 million) of child deaths before the age of five years were attributed to under nutrition in 2004. Vulnerable communities generally consume a diet based mainly on plant-based staples, and a low consumption of animal source foods, fruit and vegetables predisposes these communities to micronutrient deficiencies. In this paper, South African data is used to illustrate the poor diet and consequences thereof in vulnerable communities. Childhood malnutrition and maternal overweight often co-exist in the same community. Dietary modification strategies to address malnutrition should therefore focus on the nutritional quality of the diet, rather than on energy content only. Animal foods are particularly rich sources of bio-available iron, zinc and vitamin A (the micronutrients of greatest concern), and these nutrients are difficult to obtain in adequate amounts from plant foods alone. Foods of animal sources (particularly muscle tissue) also enhance the absorption of the less bio-available non-heme iron. Dietary modification strategies need to be introduced from a very young age. In the developed world, commercially available baby products play an important role in meeting the nutritional requirements of infants, but in developing countries cost and possible contamination (bottle feeds) prohibit the use of baby products. Addition of small amounts of foods of animal sources can improve the nutritional quality of the diet, as well as the nutritional status and functional outcomes of vulnerable populations. A moderate increase in the consumption of animal source foods will provide critical nutritional benefits without a significant increase in the risk of chronic diseases in the poor. Constraints for frequent consumption of animal source foods include availability, affordability and lack of cold storage facilities. Adequate dietary intake is essential for good nutrition, but frequent infections can also lead to malnutrition. The underlying causes of malnutrition, i.e. inadequate care on the one hand, and insufficient health services and an unhealthy environment on the other hand, should also therefore be addressed.

Bioavailability in healthy adults of efavirenz capsule contents mixed with a small amount of food

The effect of mixing the contents of efavirenz capsules (sprinkles) with a small amount of food on the bioavailability and pharmacokinetics of efavirenz in healthy adults was evaluated. In a randomized, three-period, crossover study, 24 healthy adult subjects were divided equally into two groups. Group I received treatments A, B, and C, and those in group II received treatments A, D, and E. Treatment A was three efavirenz 200-mg intact capsules under fasting conditions. Treatments B, C, D, and E were three efavirenz 200-mg capsule contents mixed with two teaspoons of applesauce, grape jelly, yogurt, or infant formula, respectively. A single dose was given on days 1, 21, and 41. The steady-state mean maximum observed concentration, time of maximum observed concentration, area under the concentration-time curve (AUC) half-life, taste, and safety were assessed. The AUC after administration of a single 600-mg dose of efavirenz sprinkles mixed with two teaspoons of any of the food vehicles to healthy adults was bioequivalent to a 600-mg efavirenz dose given as intact capsules under fasting conditions. Subjects rated efavirenz mixed with grape jelly as the most palatable. Adverse events and laboratory abnormalities were similar for all treatments. The AUC of efavirenz 600 mg administered as capsule sprinkles with two teaspoons of applesauce, grape jelly, yogurt, or infant formula was bioequivalent to a single dose of efavirenz 600 mg given as intact capsules under fasting conditions in healthy adults.

Summer Burrows of Ord's Kangaroo Rats (Dipodomys ordii) in Western Nebraska: Food Content and Structure

Extent of larder hoarding differs among species of kangaroo rats, and limited information is available for food stored in burrows by Ord's kangaroo rat (Dipodomys ordii)—the most widespread species of Dipodomys. I excavated 9 burrows recently used by adult D. ordii during summer in the Sandhill Region of Nebraska. I observed only small quantities of food stored in burrows. Eight of 9 burrows contained segments of sand dropseed (Sporobolus cryptandrus) in limited quantities. These segments consisted of upper leaves with fruits (containing seeds) housed in sheaths. My observations represent the first documentation of D. ordii storing food in burrows under natural conditions. Compared to the burrows of other species of kangaroo rat, burrows of D. ordii were simple in structure with 1 main tunnel and 1–3 entrances. In summer, Ord's kangaroo rats commonly harvest seeds from plants in the Sandhill Region of Nebraska, but individuals apparently do not store large quantities of food in burrows, which suggests they store food in scatter hoards during this season.

Cognitive impulsivity in animal models: Role of response time and reinforcing rate in delay intolerance with two-choice operant tasks

Impulsivity, a key symptom of ADHD (attention-deficit hyperactivity disorder), is also common in obsessive-compulsive and addictive disorders. There is rising interest in animal models of inhibitory-control impairment. Adolescent rats were tested daily in the intolerance-to-delay (ID) task (session 25 min, timeout 20 s), involving choice between either immediate small amount of food (SS), or larger amount of food after a delay (LL). The mixed 5-HT(1A/7) agonist (8-OH-DPAT, 0 or 0.060 mg/kg i.p.) was administered acutely just before the last three sessions at highest delays. In addition to the classical choice parameter (percent LL preference), the spontaneous waiting (termed response time, RT) occurring between end of a timeout (TO) and next nose-poke was calculated. The pace between consecutive reinforcer deliveries is given by the mean inter-trial interval (mITI, i.e. TO + RT). Hence, the impact of any given delay may be proportional to this pace and be expressed as delay-equivalent odds, i.e. the extent by which delays are multiples of the mITI. Data revealed that RT/mITI increased sharply from around 15 s/35 s to around 30 s/50 s when imposed delay changed from 30 s to 45 s (i.e. odds from 0.91 to 1.06). This suggests that rats adopted a strategy allowing them to keep in pace with perceived reinforcing rate. The increasing delay constraint directly influenced the length of rats' spontaneous waiting (RT) before next decision. For higher delays, with odds >1, rats shifted to a clear-cut SS preference, which is devoid of any exogenous temporal constraint. A challenge with 8-OH-DPAT (0 or 0.060 mg/kg i.p.) decreased impulsive choice but also increased RT. Thus, tapping onto 5-HT(1A/7) receptors slightly enhanced RT/mITI values, possibly reflecting ability of rats to cope with slower reinforcing rates and/or with delay-cancelled reward paces. In summary, delay-induced states of aversion may arise from the innate tendency to rely on a regular rate of reinforcement. Conversely, a drug-enhanced capacity to cope with delay may involve an internal ability to adjust expectancy about such a reinforcing rate.

Ecological features of permanent ectoparasites

There are more than 9000 species of permanent ectoparasites of terrestrial vertebrates among insects and acarines. Permanent ectoparasites spend entire life time or only part of their life cycle on and inside the skin, hairs and feathers of their hosts. Such ectoparasites feed on blood, lymph, products of dermal glands and particles of skin, hairs and feathers. Permanent ectoparasites can be characterized by the following features: often consumption of small amounts of food, small to moderate fecundity, short period of development of one generation, short life span and incapability to starvation for a long period of time. They infest new host individuals through the direct contact between hosts or by the phoretic way.

Relationships Between Fruits And Seed Sizes, Germination And Early Seedling Growth Of Some Edible Plant Species In Southeastern Nigerian Rainforest

Relationships between fruits and seeds sizes; seed germination and early seedling growth of seedlings of 25 plant species were studied at the University of Agriculture, Umudike, Nigeria. The destruction of Nigeria rainforest without an assured method of naturally regenerating it, has contributed to some edible plant species being either fewer per hectare or endangered in abandoned farmlands. Fruits of 25 plant species were collected from the rainforest at Umudike, Nigeria. For each plant species 100 fruits and seeds were selected for the study. All the fruits containedbetween 1 and 30 seeds. The length, width and weight of fruits and seeds of the plant species varied within and between plant species. The biggest fruits were those of Pentaclethra macrophylla with length ranging of between 435.22 and 508.52 mm while the biggest seeds were those of Plukernetia conophora each had length range of between 60.39 and 98.14 mm.. The length and width of each fruit and seed were measured using Digimatic Mitutoyo caliper. For each fruit and seeds, the weight was measured using electric weighing balance, Ohaus Corporation, Model Scout Prospu 402. Broadcast of 100 seeds of each plant species was done on germination boxes of size 30 x 60 cm, and watered twice daily. All the viable seeds germinated, however, mechanical dormancy was observed in the fruits of Spondias mombin, Tetrapleura tetraptera and Canarium schweinfurthii, whose seeds were covered by fibrous material. There was no co-relationship between seed size and germination rate because both small and big seeds started germination within the same week. The observed seedling types were Phanerocotylar – epigeal – reserve, (52.9%), Phanerocotylar – epigeal – foliaceous (20%) and Cryptocotylar – hypogeal – reserve (12.0 %), Phenerocotylar – hypogeal – reserve (8) and Cryptocotylar-epigeal-reserve (8%). There was a significant different inthe growth rate of seedlings of the plant species. The rate of growth of 0.05 m per month of seedlings of Persea americana and Dacryodes edulis was comparatively high presumably because of the food stored in the seed. The rate of growth of 0.001 m per month of Dialium guineense seedlings was very poor presumably because of the relatively small quantity of food stored in the seed. Carpolobia lutea produced numerous branches exhibiting shrubby characteristics. It is recommended that fruits should be collected from different provenances and their proximate composition analysed. Fruits having desirable qualities should be genetically improved.

Process-induced food toxicants: occurrence, formation, mitigation, and health risks

Preface. List of contributors. PART I: Specific Toxicants Related to Processing Technology. 1 Introduction to Food Process Toxicants ( David R. Lineback and Richard H. Stadler ). 1.1 History and Role of Food Processing. 1.2 General Approaches to Food Processing. 1.3 Concerns about Food Safety during Food Processing. 1.4 Food-Borne Processing Toxicants: Setting Priorities. 1.5 Issues of Process Toxicants Present in Small Amounts in Foods. 1.6 Outlook. 2 Thermal Treatment. 2.1 Acrylamide ( Craig Mills, Donald S. Mottram, and Bronislaw L. Wedzicha ). 2.2 Acrolein ( Takayuki Shibamoto ). 2.3 Heterocyclic Aromatic Amines ( Robert J. Turesky ). 2.4 Hazards of Dietary Furan ( P. Michael Bolger, Shirley S-H. Tao, and Michael Dinovi ). 2.5 Hydroxymethylfurfural (HMF) and R elated Compounds ( Francisco J. Morales ). 2.6 Chloropropanols and Chloroesters ( Colin G. Hamlet and Peter A. Sadd ). 2.7 Maillard Reaction of Proteins and Advanced Glycation End Products (AGE s) in Food ( Thomas Henle ). 2.8 Polyaromatic Hydrocarbons ( Jong-Heum Park and Trevor M. Penning ). 3 Fermentation. 3.1 Ethyl Carbamate (Urethane) ( Colin G. Hamlet ). 3.2 Biogenic Amines ( Livia Simon Sarkadi ). 4 Preservation. 4.1 N -Nitrosamines, Including N -Nitrosoaminoacids and Potential Further Nonvolatiles ( Michael Habermeyer and Gerhard Eisenbrand ). 4.2 Food Irradiation ( Eileen M. Stewart ). 4.3 Benzene ( Adam Becalski and Patricia Nyman ). 5 High Hydrostatic Pressure ( Alexander Mathys and Dietrich Knorr ). 5.1 Introduction. 5.2 HPP. 5.3 Chemical and Matrix Effects. 5.4 Microbial Effects. 5.5 Allergenic Potential. 5.6 Conclusion. Annex. References. 6 Alkali and/or Acid Treatment. 6.1 The Dietary Significance of Processing-Induced Lysinoalanine in Food ( Mendel Friedman ). 6.2 Dietary Significance of Processing-Induced D-Amino Acids ( Mendel Friedman ). 6.3 Chloropropanols ( Jan Velisek ). PART II: General Considerations. 7 Application of HACCP for the Management of Processing Contaminants ( Yasmine Motarjemi, Richard H. Stadler, Alfred Studer, and Valeria Damiano ). 7.1 Introduction. 7.2 Processing Contaminants: Risks and Control Measures. 7.3 HACCP: the Backbone of Food Safety Assurance. 7.4 Application of HACCP to Processing Contaminants. 7.5 A Case Study on the Application of the HACCP Approach for the Management of Processing Contaminants: Extruded Cereal Snack. 7.6 Conclusions. Acknowledgment. References. 8 Emerging Food Technologies ( Fanbin Kong and R. Paul Singh ). 8.1 Introduction. 8.2 Pulsed Electric Fields. 8.3 Pulsed UV Light. 8.4 Ultrasound. 8.5 Microwave and Radio-Frequency Processing. 8.6 Ohmic Heating. 8.7 Infrared Heating. References. 9 Food Processing and Nutritional Aspects ( Josef Burri, Constantin Bertoli, and Richard H. Stadler ). 9.1 Introduction. 9.2 Food Processing and Major Benefits. 9.3 Conclusions and Future Research Needs. References. 10 Risk Communication ( David Schmidt and Danielle Schor ). 10.1 Introduction. 10.2 Attitudes about Food-Related Risks. 10.3 Ranking Risks: Placing Risks in Context. 10.4 Effective Communication Techniques: Examples. 10.5 Challenges and Barriers. 10.6 Future Prospects. References. 11 Risk/Risk and R isk/Benefit Considerations ( Leif Busk ). 11.1 Introduction. 11.2 Mitigation and Potential Risk of Other Possible Food Safety-Related Issues. 11.3 Research Needs. 11.4 Challenges and Future Prospects. References. Index.