Spacing and Three-bird Flights of mallards breeding in pothole habitat

1983 ◽  
Vol 61 (4) ◽  
pp. 839-847 ◽  
Author(s):  
Rodger D. Titman
Keyword(s):  
Average Length ◽  
Behaviour Pattern ◽  
Territorial Behaviour ◽  
Nutrient Requirements ◽  
Natural Conditions ◽  
Wild Stock ◽  
Bird Flight ◽  
Mixed Reproductive Strategy ◽  
Forced Copulation ◽  
Fixed Area

Wild mallards (Anas platyrhynchos) were observed in pothole habitat near Minnedosa, Manitoba. The breeding mallards behaved territorially: both members of a pair were attached to a fixed area, and males were aggressive toward intruding females and pairs. Territorial behaviour was most pronounced during a brief period (13–22 days) from just prior to laying until early incubation. The most frequently observed aggressive behaviour pattern was the Three-bird Flight which effectively expelled intruders from the territory. The behaviour of birds in one area where density was artificially increased through the release of hand-reared birds of wild stock was compared with that of mallards under natural conditions. Under higher population density, pairs occupied smaller territories, the frequency of Three-bird Flights was reduced, and the average length and number of participants in each pursuit was reduced. Territorial behaviour in mallards appears to have evolved because of advantages to the male in preventing cuckoldry by defending his mate from males intent on forced copulation, alerting her to the presence of predators, and in allowing her to feed with a minimum of interruption during this period when she has special nutrient requirements. Three-bird Flights do not appear to be strictly territorial. Males appear to employ a mixed reproductive strategy whereby they defend their mates and also seek to inseminate females other than their mates.

Forced Copulation as a Reproductive Strategy of Male Lesser Scaup: a Field Test of Some Predictions

Behaviour ◽  
1985 ◽  
Vol 92 (1-2) ◽  
pp. 146-167 ◽  
Author(s):  
Alan D. Afton
Keyword(s):  
Reproductive Effort ◽  
Strong Support ◽  
Pair Formation ◽  
Exact Nature ◽  
Natural Conditions ◽  
Annual Variations ◽  
Lesser Scaup ◽  
Forced Copulation ◽  
And Performance ◽  
The Relationship

I presented evidence that sperm transfer can occur during forced copulation (FC) under natural conditions, and tested predictions of the fertilization strategy hypothesis, with field data from a marked population of lesser scaup breeding in southwestern Manitoba. As predicted, males directed FC attempts at fertilizable females and seemingly had tactics that increased their effectiveness in inseminating such females. Males selected older females (the more productive) when attempting FCs in 1 year of the study. FC rates were highest in the morning when chances of successful fertilization were probably highest. FC rates were positively correlated with annual variations in female reproductive effort and performance, but the exact nature of the relationship requires further study. Mate-and nonmate-defense by males and other behaviours which probably function as anticuckoldry tactics were observed. Contrary to BARASH'S (1977a) prediction, paired males attempted FCs more frequently than did unpaired males. Although pair formation through mate-switches is probably a more profitable strategy than FC for unpaired males, FC may be an important "last resort" strategy for older, experienced unpaired males late in the season. In general, my results provided strong support for the male fertilization strategy hypothesis.

Experimental evaluation of agonistic behaviour, chemical communication, spacing, and intersexual associations of the Eastern Red-backed Salamander (Plethodon cinereus) near its northern range limit

2015 ◽  
Vol 93 (10) ◽  
pp. 773-781 ◽  
Author(s):  
N. Rollinson ◽  
D. Hackett
Keyword(s):  
Plethodon Cinereus ◽  
Experimental Chamber ◽  
Agonistic Behaviour ◽  
Foraging Activity ◽  
Territorial Behaviour ◽  
Range Limit ◽  
Pheromonal Communication ◽  
Northern Range Limit ◽  
Fixed Area ◽  
Modest Degree

Territorial behaviour is the use of aggression and advertisement in the defense of a fixed area. In the Eastern Red-backed Salamander (Plethodon cinereus (Green, 1818)), territoriality is prevalent in Virginia, USA, near the southern extent of its range, but few studies have examined whether northern populations exhibit territorial behaviour. We tested for some prerequisites of territorial behaviour in P. cinereus at the northern extent its range, near North Bay, Ontario, Canada. In laboratory trials, we found that adult male P. cinereus exhibited a modest degree of aggression, and intruding salamanders attempted to escape the experimental chamber more often than residents. We also found that P. cinereus were able to differentiate between familiar and unfamiliar substrates, suggesting pheromonal communication and a potential for territorial advertisement. However, while male–female pairs were common at six sampling sites during the mating season, adult salamanders consistently exhibited a random spatial distribution during the nonmating season. Our study suggests that local P. cinereus exhibit low-level aggression but may not defend fixed areas. One possibility is that P. cinereus may generally not benefit from territorial behaviour in cooler climates, as evapotranspiration rates will be lower and foraging activity less restricted compared with more southern climates.

EURRECA’s Approach for Estimating Micronutrient Requirements

2011 ◽  
Vol 81 (4) ◽  
pp. 256-263 ◽  
Author(s):  
Christophe Matthys ◽  
Pieter van ‘t Veer ◽  
Lisette de Groot ◽  
Lee Hooper ◽  
Adriënne E.J.M. Cavelaars ◽  
...  
Keyword(s):  
Reference Values ◽  
Policy Decision ◽  
Individual Variability ◽  
The Body ◽  
Decision Makers ◽  
Nutrient Requirements ◽  
Factorial Approach ◽  
Dietary Reference Values ◽  
Health Policy Decision ◽  
Quantitative Integration

In Europe, micronutrient dietary reference values have been established by (inter)national committees of experts and are used by public health policy decision-makers to monitor and assess the adequacy of diets within population groups. The approaches used to derive dietary reference values (including average requirements) vary considerably across countries, and so far no evidence-based reason has been identified for this variation. Nutrient requirements are traditionally based on the minimum amount of a nutrient needed by an individual to avoid deficiency, and is defined by the body’s physiological needs. Alternatively the requirement can be defined as the intake at which health is optimal, including the prevention of chronic diet-related diseases. Both approaches are confronted with many challenges (e. g., bioavailability, inter and intra-individual variability). EURRECA has derived a transparent approach for the quantitative integration of evidence on Intake-Status-Health associations and/or Factorial approach (including bioavailability) estimates. To facilitate the derivation of dietary reference values, EURopean micronutrient RECommendations Aligned (EURRECA) is developing a process flow chart to guide nutrient requirement-setting bodies through the process of setting dietary reference values, which aims to facilitate the scientific alignment of deriving these values.

Pilonidal Sinus: How to Choose Between Excision and Open Granulation Versus Excision and Primary Closure?

Swiss Surgery ◽  
2002 ◽  
Vol 8 (6) ◽  
pp. 255-258 ◽  
Author(s):  
Perruchoud ◽  
Vuilleumier ◽  
Givel
Keyword(s):  
Hospital Stay ◽  
Pilonidal Sinus ◽  
Primary Closure ◽  
Average Length ◽  
Length Of Hospital Stay ◽  
Healing Time ◽  
Incision And Drainage ◽  
The Mean ◽  
Primary Healing

Aims: The purpose of this study was to evaluate excision and open granulation versus excision and primary closure as treatments for pilonidal sinus. Subjects and methods: We evaluated a group of 141 patients operated on for a pilonidal sinus between 1991 and 1995. Ninety patients were treated by excision and open granulation, 34 patients by excision and primary closure and 17 patients by incision and drainage, as a unique treatment of an infected pilonidal sinus. Results: The first group, receiving treatment of excision and open granulation, experienced the following outcomes: average length of hospital stay, four days; average healing time; 72 days; average number of post-operative ambulatory visits, 40; average off-work delay, 38 days; and average follow-up time, 43 months. There were five recurrences (6%) in this group during the follow-up period. For the second group treated by excision and primary closure, the corresponding outcome measurements were as follows: average length of hospital stay, four days; average healing time, 23 days; primary healing failure rate, 9%; average number of post-operative ambulatory visits, 6; average off-work delay, 21 days. The average follow-up time was 34 months, and two recurrences (6%) were observed during the follow-up period. In the third group, seventeen patients benefited from an incision and drainage as unique treatment. The mean follow-up was 37 months. Five recurrences (29%) were noticed, requiring a new operation in all the cases. Discussion and conclusion: This series of 141 patients is too limited to permit final conclusions to be drawn concerning significant advantages of one form of treatment compared to the other. Nevertheless, primary closure offers the advantages of quicker healing time, fewer post-operative visits and shorter time off work. When a primary closure can be carried out, it should be routinely considered for socio-economical and comfort reasons.

Thierry Kuntzel and the Rise of Video Art

2018 ◽  
Author(s):  
Hilary Radner ◽  
Alistair Fox
Keyword(s):  
New Technology ◽  
Video Art ◽  
Video Technology ◽  
Natural Conditions

Raymond Bellour describes how his interest in video art grew out of his personal friendship with Thierry Kuntzel and the latter’s growing interest in experimental filmmaking using the new technology, and how this interest prompted him to seek to understand how the new medium was leading to a modification of perception. He goes on to explain how video technology enables the production of images that escape the natural conditions deemed to constrain photography, also emphasizing the influence of painting on video art.

Extrakorporális és intrakorporális anasztomózis rövid távú eredményeinek összehasonlítása malignus daganat miatt végzett laparoszkópos jobb oldali hemikolektómia esetén

2020 ◽  
Vol 73 (4) ◽  
pp. 148-152
Author(s):  
Kornél Vajda ◽  
László Sikorszki
Keyword(s):  
Length Of Stay ◽  
Gold Standard ◽  
Average Length ◽  
Colon Surgery ◽  
Right Hemicolectomy ◽  
Malignant Tumours ◽  
Short Term ◽  
Significant Difference ◽  
Laparoscopic Assisted ◽  
Laparoscopic Hemicolectomy

Összefoglaló. Bevezetés: A laparoszkópia térhódítása a jobb oldali colon műtéteknél is nyilvánvaló. Ma legtöbb helyen a laparoszkóposan asszisztált jobb oldali hemikolektómia extrakorporális anasztomózissal a gold standard. A morbiditás randomizált vizsgálatok alapján még 30% körüli. A technikai fejlődés lehetővé tette az intrakorporális anasztomózist. Célkitűzés: Retrospektív módon elemezni rosszindulatú jobb oldali vastagbéldaganat miatt végzett laparoszkópos hemikolektómiák rövid távú eredményeit a két módszer összehasonlításával. Eredmények: 2018. 01. 01. – 2019. 12. 31. között 184 jobb oldali hemikolektómiát végeztünk, ezek közül 122 történt malignus betegség miatt. 51 esetben nyitott és 71 esetben laparoszkópos műtét történt. 37 férfi (átlagéletkor: 70,59 év) és 34 nő (átlagéletkor: 72,14 év) volt. 50 esetben extrakorporális (EA) és 21 esetben pedig intrakorporális anasztomózist (IA) végeztünk. Az EA csoportban 18, míg az IA csoportban 3 szövődmény alakult ki 30 napon belül (p = 0,067). Az EA csoportból 3, az IA csoportból 1 beteget veszítettünk el 30 napon belül (p = 0,66). Az átlagos ápolási idő az EA csoportban 9,48 (5–32) nap, míg az IA csoportban 6,52 (4–19) nap volt (p = 0,001) a szövődményes esetekkel együtt. A szövődményes esetek nélkül az EA csoportban 6,35 (5–10) nap, az IA csoportban pedig 5,55 (4–8) napnak bizonyult (p = 0,09). A műtéti idő pedig az EA csoportban 147 (90–240) perc, az IA csoportban pedig 146,47 (90–265) perc volt (p = 0,11). Konklúzió: Az irodalommal összhangban azt találtuk, hogy IA esetén kevesebb a szövődmény, ezzel is összefüggésben rövidebb az átlagos ápolási idő, és a műtéti időt tekintve nincs szignifikáns különbség. Ezeket figyelembe véve az intrakorporális anasztomózis javasolható jobb oldali laparoszkópos hemikolektómia esetén. Summary. Introduction: Laparoscopy became evident for right-sided colon surgery too. Today the laparoscopic-assisted right-hemicolectomy is the gold standard with extracorporeal anastomosis. Morbidity according to randomized trials is still approximately 30%. The development of the surgical technique resulted in the creation of intracorporeal anastomosis. Our aim was to compare the short-term results of the two methods. Aim: To analyse the short-term results of right-sided hemicolectomy that were performed due to malignant tumours with the comparison of the two methods. Results: A cohort of 184 right-sided hemicolectomy were performed from 01.01.2018 to 31.12.2019 from which 122 were operated on because of a malignant disease. 51 open and 71 laparoscopic operations were performed. The average age of 37 men and 34 women were 70.59 and 72.14 years, respectively. 50 patients underwent extracorporeal (EA) anastomosis and 21 intracorporeal (IA) anastomosis. Within 30 days the number of complications were 18 in the EA group and 3 in the IA group (p = 0.067). 3 from the EA group and 1 from IA group died within 30 days (p = 0.66). The average length of stay were 9.48 days in the EA group and 6.52 days in the IA group together with the complicated cases (p = 0.001) while 6.35 days and 5.55 days without the complicated cases (p = 0.09). The average duration of operation was 147 minutes in the EA and 146.47 minutes in the IA group (p = 0.11). Conclusion: We found concordance with the literature that there are fewer complications in case of IA which might be related to shorter length of stay. There is no significant difference between the surgical times. Bearing these facts in mind, IA might be suggested for right- sided laparoscopic hemicolectomy.

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