Emperor penguin body surfaces cool below air temperature.

Emperor penguins Aptenodytes forsteri are able to survive the harsh Antarctic climate because of specialized anatomical, physiological and behavioural adaptations for minimizing heat loss. Heat transfer theory predicts that metabolic heat loss in this species will mostly depend on radiative and convective cooling. To examine this, thermal imaging of emperor penguins was undertaken at the breeding colony of Pointe Géologie in Terre Adélie (66°40' S 140° 01' E), Antarctica in June 2008. During clear sky conditions, most outer surfaces of the body were colder than surrounding sub-zero air owing to radiative cooling. In these conditions, the feather surface will paradoxically gain heat by convection from surrounding air. However, owing to the low thermal conductivity of plumage any heat transfer to the skin surface will be negligible. Future thermal imaging studies are likely to yield further insights into the adaptations of this species to the Antarctic climate.

Estimating metabolic heat loss in birds and mammals by combining infrared thermography with biophysical modelling.

Infrared thermography (IRT) is a technique that determines surface temperature based on physical laws of radiative transfer. Thermal imaging cameras have been used since the 1960s to determine the surface temperature patterns of a wide range of birds and mammals and how species regulate their surface temperature in response to different environmental conditions. As a large proportion of metabolic energy is transferred from the body to the environment as heat, biophysical models have been formulated to determine metabolic heat loss. These models are based on heat transfer equations for radiation, convection, conduction and evaporation and therefore surface temperature recorded by IRT can be used to calculate heat loss from different body regions. This approach has successfully demonstrated that in birds and mammals heat loss is regulated from poorly insulated regions of the body which are seen to be thermal windows for the dissipation of body heat. Rather than absolute measurement of metabolic heat loss, IRT and biophysical models have been most useful in estimating the relative heat loss from different body regions. Further calibration studies will improve the accuracy of models but the strength of this approach is that it is a non-invasive method of measuring the relative energy cost of an animal in response to different environments, behaviours and physiological states. It is likely that the increasing availability and portability of thermal imaging systems will lead to many new insights into the thermal physiology of endotherms.

Ecophysiological response of Adelie penguins facing an experimental increase in breeding constraints.

Foraging strategies play a key role in breeding effort. Little is known, however, about their connection with hormonal and nutritional states, especially when breeding constraints vary. Here, we experimentally increased foraging costs and thus breeding constraints by handicapping Adélie penguins (Pygoscelis adeliae) with dummy devices representing 3-4% of the penguins' cross-sectional area. We examined food-related stress (via plasma corticosterone concentration) and nutritional state (via metabolite levels). Concurrently, we investigated the use of ecological niches via the isotopic signature of red blood cells indicating the trophic position (delta(15)N) and the spatial distribution (delta(13)C) of penguins. Handicapped birds performed approximately 70% longer foraging trips and lost approximately 60% more body mass than controls and their partners. However, corticosterone levels and the nutritional state were unchanged. The isotopic signature revealed that males and females differed in their foraging behaviour: upper trophic levels contributed more in the males' diet, who foraged in more pelagic areas. Handicapped and partner birds adopted the same strategy at sea: a shift towards higher delta(13)C values suggested that they foraged in more coastal areas than controls. This change in foraging decisions may optimize feeding time by decreasing travelling time. This may partly compensate for the presumed lower foraging efficiency of handicapped birds and for the energetic debt of their partners who had to fast approximately 70% longer on the nest. We propose that this flexible use of ecological niches may allow birds facing increased breeding constraints to avoid chronic stress and to minimize the impact on their body condition.

[Algorithm for an etiological classification of prematurity]. / Algoritmo para la asignación etiológica de la prematuridad.

UNLABELLED: The etiology of preterm birth is difficult to classify. It is usually divided into three clinical types according to its clinical presentation: medically indicated; caused by ruptured membranes; and spontaneous or idiopathic. However, this classification is controversial, imprecise and can result in multiple interpretations when applied. OBJECTIVE: To design an etiologically based classification of preterm birth, and to design a system to easily assign each case during the perinatal period. METHODS: Review of literature, qualitative analysis using consensus methods through nominal group technique, and quantitative analysis of a pilot study using a first version of the algorithm. RESULTS: A classification is made to establish a general division between the "primary cause" and "associated causes" of preterm birth, that allows remote causes or risk factors to be included. The primary cause includes seven categories: inflammatory (ruptured membranes and related); vascular (intrauterine growth restriction and related); maternal-local; maternal-systemic; fetal pathology; fetal distress; idiopathic. The medically indicated preterm birth is defined as a previous or independent category and so is compatible with the other, previously mentioned causes . An algorithm was designed to make it easier to classify the primary cause of preterm birth using a flowchart. CONCLUSIONS: A pragmatic classification of preterm birth is proposed that may help to achieve better precision and agreement between clinicians.

Consecutive aquatic jump-gliding with water-reactive fuel.

Robotic vehicles that are capable of autonomously transitioning between various terrains and fluids have received notable attention in the past decade due to their potential to navigate previously unexplored and/or unpredictable environments. Specifically, aerial-aquatic mobility will enable robots to operate in cluttered aquatic environments and carry out a variety of sensing tasks. One of the principal challenges in the development of such vehicles is that the transition from water to flight is a power-intensive process. At a small scale, this is made more difficult by the limitations of electromechanical actuation and the unfavorable scaling of the physics involved. This paper investigates the use of solid reactants as a combustion gas source for consecutive aquatic jump-gliding sequences. We present an untethered robot that is capable of multiple launches from the water surface and of transitioning from jetting to a glide. The power required for aquatic jump-gliding is obtained by reacting calcium carbide powder with the available environmental water to produce combustible acetylene gas, allowing the robot to rapidly reach flight speed from water. The 160-gram robot could achieve a flight distance of 26 meters using 0.2 gram of calcium carbide. Here, the combustion process, jetting phase, and glide were modeled numerically and compared with experimental results. Combustion pressure and inertial measurements were collected on board during flight, and the vehicle trajectory and speed were analyzed using external tracking data. The proposed propulsion approach offers a promising solution for future high-power density aerial-aquatic propulsion in robotics.

Associations between neural injury markers of intrauterine growth-restricted infants and neurodevelopment at 2 years of age.

Objectives: The aim of this study was to evaluate the relationships between brain injury biomarkers in intrauterine growth-restricted (IUGR) infants (S100B and neuron-specific enolase (NSE)) and neurodevelopment at 2 years of age. Methods: This prospective case-control study was a cooperative effort among Spanish Maternal and Child Health Network (Retic SAMID) hospitals. At inclusion, biometry for estimated fetal weight and feto-placental Doppler variables were measured for each infant. Maternal venous blood and fetal umbilical arterial blood samples were collected at the time of delivery and neural injury markers S100B and NSE concentrations were measured. Neurodevelopment was evaluated at 2 years of age using the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III). Results: Fifty six pregnancies were included. Thirty-one infants were classified as IUGR and 25 as non-IUGR. Neurodevelopmental evaluation at 2 years of age indicated that there were no between-group differences for any of the tests. For all patients in both groups, we found statistically significant inverse relationships between the concentrations of NSE in the cord blood and the results of the cognitive test (r = -271, p = .042), fine motor subtest (r = -280, p = .036), and social-emotional test (r = -349, p = .015). We also found statistically significant differences between the concentrations of S100B in the cord blood and the results of the cognitive test (r = -306, p = .022) and expressive communication subtest (r = -304, p = .023). For the IUGR group, we found a significant inverse relationship between the concentrations of S100B in the maternal serum and the results of adaptive behavior test (p < .05). In the non-IUGR group, we found statistically significant inverse relationships between the concentration of NSE in the cord blood and the results of the fine motor subtest (r = -446, p = .025) and social-emotional test (r = -489, p = .021). The difference between the concentration of S100B in the cord blood and the language composite score was also statistically significant (p = .038). Conclusions: At 2 years of age, the concentrations of NSE and S100B were higher in the non-IUGR and IUGR groups with the worst scores for some areas of neurodevelopmental evaluation. The value of these biomarkers for prognostic neurodevelopmental use requires further investigation for both non-IUGR and IUGR infants.

[Reduced postnatal growth in very low birth weight newborns with GE < or = 32 weeks in Spain]. / Restricción posnatal del crecimiento en recién nacidos españoles de muy bajo peso con edad gestacional menor o igual a 32 semanas.

AIM: To analyze postnatal growth restriction in a cohort of very low birth weight (VLBW) infants with gestational age < or = 32 weeks in 55 Spanish neonatal units (SEN 1500 Network) during 2002 and 2003. METHODS: Weight, length and head circumference were recorded at birth, and at discharge. Weight was also recorded at 28 days postnatal, and 36 weeks of postmenstrual age. Growth restriction was measured as the shift in weight z score from birth to 28th day. RESULTS: The study included 2317 VLBW infants. Weight z score at birth, 28 days, 36 weeks of postmenstrual age and discharge were: -0.66 +/- 1.3, -2.54 +/- 1.35, -3.12 +/- 1.7, -1.56 +/- 1.1, respectively. Length z score at birth and at discharge were: -0.88 +/- 1.8, and -1.97 +/- 1.56. Head circumference z score at birth and at discharge: -0.83 +/- 1.87, and -0.60 +/- 1.96. Prenatal steroids, gestational age, place of birth, type of hospital, CRIB score, symptomatic patent ductus arteriosus and late-onset bacterial sepsis were related with the shift in weight z score at 28 days (multiple linear regression), but explained very little (14 %) of his change. Weight and length at discharge were under the 10th percentile in 77 % and 80 % of the infants, respectively. CONCLUSIONS: VLBW infants < or = 32 GA suffer postnatal growth restriction with respect to intrauterine growth pattern, which is more relevant in the first 28 days of life, in patients with more severe illnesses, and differs among neonatal units. Perinatal and neonatal items evaluated are poorly related with restriction.

Cerebrospinal fluid leucocyte counts in healthy neonates.

OBJECTIVES: To determine the cerebrospinal fluid (CSF) white blood cell (WBC) count of normal term neonates, and compare the CSF WBC profile of normal and symptomatic infants without infection of the central nervous system (CNS). METHOD: Neonates were included if (a) they were at risk of congenital Toxoplasma infection and had undergone a lumbar puncture to assess CNS involvement, and (b) serial specific serum IgG and IgM determinations had ruled out congenital infection. According to neonatal chart reviews, 30 consecutive patients without CNS infection were classified as normal (absolutely asymptomatic) or symptomatic (any kind of symptoms). RESULTS: CSF WBC count was higher in 11 symptomatic (7/mm(3), 0-30/mm(3)) than in 19 normal (1/mm(3), 0-5/mm(3)) neonates (p<0.01). CONCLUSION: Normal neonatal CSF contains up to 5 WBCs/mm(3). Mild pleocytosis can be found in symptomatic infants without CNS infection.

Feeding behaviour of free-ranging penguins determined by oesophageal temperature.

Sea birds play a major role in marine food webs, and it is important to determine when and how much they feed at sea. A major advance has been made by using the drop in stomach temperature after ingestion of ectothermic prey. This method is less sensitive when birds eat small prey or when the stomach is full. Moreover, in diving birds, independently of food ingestion, there are fluctuations in the lower abdominal temperature during the dives. Using oesophageal temperature, we present here a new method for detecting the timing of prey ingestion in free-ranging sea birds, and, to our knowledge, report the first data obtained on king penguins (Aptenodytes patagonicus). In birds ashore, which were hand-fed 2-15 g pieces of fish, all meal ingestions were detected with a sensor in the upper oesophagus. Detection was poorer with sensors at increasing distances from the beak. At sea, slow temperature drops in the upper oesophagus and stomach characterized a diving effect per se. For the upper oesophagus only, abrupt temperature variations were superimposed, therefore indicating prey ingestions. We determined the depths at which these occurred. Combining the changes in oesophageal temperatures of marine predators with their diving pattern opens new perspectives for understanding their foraging strategy, and, after validation with concurrent applications of classical techniques of prey survey, for assessing the distribution of their prey.

Mononucleosis caused by Epstein-Barr virus and cytomegalovirus in children: a comparative study of 124 cases.

We present 124 children who had mononucleosis. The patients were selected according to strict clinical features. Twenty (16.1%) of the 124 children were proved to have cytomegalovirus mononucleosis and 104 (83.8%) children had Epstein-Barr virus mononucleosis. The symptoms were similar in both groups. Significant differences were found only for the presence of cervical lymphadenopathy, which was more frequent in the Epstein-Barr group (83.2%) compared with the cytomegalovirus group (75%). Fever was the most frequent symptom in both groups. Cytomegalovirus mononucleosis was significantly more frequent in children younger than 4 years.

[Congenital adrenal hyperplasia: an association with increased fetal nuchal translucency]. / Hiperplasia suprarrenal congénita: asociación con translucencia nucal fetal aumentada.

A neonate with increased nuchal translucency and congenital adrenal hyperplasia is described. The possible interferences in hormone assays when values are much higher than the average assay range are also discussed.

[Clinical progress of neonatal non-ketotic hyperglycinemia under treatment]. / Evolución de la hiperglicinemia no cetósica neonatal en tratamiento.

INTRODUCTION: Non-ketotic hyperglycinemia is a congenital error in the breakdown of glycine. The most common type is the classical neonatal form, which begins at the age of a few days with symptoms of lethargy, hypotonia, myoclonia, convulsions, apneas and, frequently, ends in death. Survivors usually develop intractable epilepsy and mental retardation. There is no effective treatment for this condition, but trials have been carried out with a therapy that diminishes the levels of glycine, benzoate (BZ), and another that blocks the excitatory effect in N-methyl-D-aspartate receptors: dextromethorphan (DTM). CASE REPORT: We report on the progress of a classical neonatal case, which began at the age of a few hours with hypotonia and stupor, without myoclonias or seizures, but with a suppression wave trace on the electroencephalogram (EEG). Cerebrospinal fluid (CSF) showed glycine levels of 141 micromol/L (the normal level is 6.66 +/- 2.66 micromol/L), with a CSF/plasma ratio of 0.19 (the normal ratio is < 0.02). Treatment was started on the thirteenth day with BZ and DTM, and alertness and eye fixation improved in just three days; at the same time the EEG readings become normal. The glycine level in plasma returned to normal at two months and that in CSF was considerably reduced, although with CSF/plasma levels that were still high. At present the patient is 4 years old, has never had convulsions, EEG results have always been normal, and continues with BZ, DTM, carnitine and diet. The patient has presented a high degree of hypermotoric behaviour, but is currently more attentive and more sociable, has been walking from the age of 35 months and has a quotient in the different areas of development of 40-50. CONCLUSIONS: The clinical progress made by our patient could be said to be anything but negligible, and we therefore recommend that treatment should be started as early as possible after diagnosis.

Respiratory exchanges in the incubated egg of the domestic guinea fowl.

The daily O2 uptake (MO2) and CO2 production (MCO2) rates were measured in guinea fowl eggs with a wide range of mass specific shell water vapor conductance, spGH2O [0.108 to 0.365 mg.(g.Torr.day)-1], from day 10 to the end of incubation, day 28. The respiration rate showed a plateau, from day 22 to day 24, typical of a precocial bird: MO2 approximately 21.4 and MCO2 approximately 15.2 mmol.day-1. The plateau MO2 value was that predicted by allometric relation. At the plateau, respiratory exchanges appeared significantly limited by spGH2O. The limiting effect of spGH2O on respiratory metabolism began as soon as day 18 (64% of incubation time). The respiratory ratio was 0.75 at day 10, decreased to 0.65-0.66 on days 12-14 and stabilized at 0.70-0.71 on days 20-28.

Optimum incubation conditions of the domestic guinea fowl egg.

1. During artificial incubation of 8000 guinea fowl eggs, the effects of temperature, relative humidity, rate of inflowing air and age of the laying flocks were determined. 2. Total duration of incubation was divided into setter (0 to 24 days) and hatcher (25 to 28 days) periods. Eggs transferred at the end of the setter period, (ET, % of fertile eggs) and hatching rate (HR, % of transferred eggs) were calculated, as well as the total hatching rate expressed as percentage of fertile eggs. 3. In the range 36 to 39 degrees C, temperature affected significantly (P < 0.001) ET and HR, with optima at 37.2 and 37.0 degrees C +/- 0.1 degrees C respectively. 4. During incubating period, relative humidity in the range 40 to 64% (water vapour partial pressure, PH2O = 17 to 34 Torr at 36 to 39 degrees C), significantly (P < 0.001) affected the total diffusive water loss and hatchling mass, both expressed as percentage of fresh egg mass. ET was significantly affected by water loss, the highest ET being for water loss of 13.3 +/- 0.5%. Optimal relative humidity was calculated to be 48 to 52% (PH2O = 23 to 25 Torr at 37.2 degrees C). 5. The rate of inflowing air significantly (P < 0.001) affected HR, with an optimum at 3.1 LSTPD/(h.egg). 6. The age of the laying flock significantly (P < 0.001) increased water loss; this was explained by a parallel increase of the mass specific shell conductance to water vapour. 7. Finally optimum incubation conditions were deduced, giving total hatching rates of 78 to 81% of fertile eggs, improving by 5 to 8% the best results obtained routinely in commercial practice.

Prey ingestion revealed by oesophagus and stomach temperature recordings in cormorants.

We examined the accuracy of both stomach and oesophagus temperature sensors-deployed on captive Brandt's cormorants-for determination of the mass of food ingested and the number of prey items swallowed. The oesophageal temperature sensor was a better detector of all feeding events, including that of small prey which were missed by the stomach sensor. Adapted to free-ranging animals (and coupled to data loggers for recording seawater temperature), oesophagus temperature recorders, in conjunction with both recordings of energy expenditure (e.g. doubly labelled water, heart rate) and determination of position (e.g. Argos transmitter, time/depth recorder), should provide further important insights into the foraging success of marine endotherms.

[Intra-articular steroids in chronic juvenile arthritis]. / Esteroides intraarticulares en la artritis crónica juvenil.

The use of intraarticular steroids was evaluated in 15 children with chronic pauciarticular juvenile arthritis. Of the 25 joints injected, 23 responded favorably. At the 6-month check-up, 65% remained in remission. One year after injection, 42% maintained a good response. The beneficial effect of the injection was not associated with age, sex, erythrosedimentation or arthritis duration. A small atrophic lesion in the area of the injection in one patient was the only complication.

Kinetics of stable isotope and body composition in olive baboons (Papio anubis) estimated by deuterium dilution space: a pilot study.

Morphometrics and isotope-labelled water were used to determine body composition [total body water, total body fat and fat-free mass (FFM)] of three captive female olive baboons (Papio anubis). Mean mass was 16.5 kg, comparable with other captive settings but heavier than wild olive baboons. Average water content was 66%; FFM averaged 90.5%. Baboon females have less body fat than human counterparts. Compared with captive or wild baboons, these females were adequately nourished for their energy expenditure. A positive association between total mass and FFM existed, but due to the small sample no general relationship was observed for body fat or FFM and condition or size measures. The kinetics of deuterium equilibration in body fluids for baboons was determined as 3-4 hours after injection, similar to that for humans. Deuterium dilution technique appears to be an appropriate method for studying body composition in baboons, although a larger sample is needed for relationships between morphometric indices and body composition.