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Notes: This article describes a new, direct way to measure the time evolution of single light pulses in the subnanosecond region using time-of-flight analysis. The light pulse is coupled into a set of 40 optical fibers of increasing length arranged in an array. The output of the fiber array is imaged onto a fast gated optical imager (gatewidth 100 ps) coupled to a CCD camera (12 bit). The intensified part of the pulse of each fiber corresponds to the intensity of the light pulse at a different time due to the different transmission time of each fiber. Additional, two-dimensional (2D) spatial resolution is possible if image guides are used instead of fibers. The temporal resolution is limited by the gatewidth of the detector. The difference in length between the longest and the shortest fiber determines the total period of time displayed by the system (1 ns). The pulse characteristics of a recently developed short-pulse Raman-excimer laser are analyzed as an example of an application. Laser parameters like pulse length, energy stability, and jitter are measured with the fiber array. © 1996 American Institute of Physics.

Notes: Objective  To facilitate understanding of disagreement between mothers and adolescents when they report on adolescents’ mental symptoms, discrepancy of reports were studied in relation to depressive symptoms of mothers and self-esteem of adolescents.Participants  Sixty-eight mother–adolescent pairs participated. All the adolescents (11–17 years) were referred to child and adolescent psychiatric outpatient clinics in Norway for emotional or behavioural disorders.Methods  The adolescents completed the questionnaire Youth Self Report (YSR), and mothers completed the corresponding Child Behaviour Checklist (CBCL). Maternal depression was measured with the Hospital Anxiety and Depression Scales and adolescent self-esteem was measured with Self-Perception Profile for Adolescents.Results  Mothers’ level of depression emerged as a significant variable (P 〈 0.001) predicting CBCL-YSR discrepancy on internalizing disorders, explaining 41% of the variance. With increased levels of depression mothers tended to report more internalizing problems compared to the adolescents. For mother–adolescent discrepancy on externalizing problems, adolescents’ age was the most significant variable. With increasing age the adolescents were more in agreement with their mothers when reporting their externalizing problems. But also self-esteem problems concerning their looks made adolescents inclined to admit more externalizing problems, thus being more in agreement with their mothers.Conclusions  Subjective, psychological variables such as mothers’ level of depression and self-esteem of adolescents may be useful to consider when interpreting informant discrepancy concerning the mental problems of adolescents.

Notes: Maximal oxygen uptake (Vo2max was evaluated after high-altitude training in rowers. Nine rowers trained in a camp at 1822 m for 3 weeks with no change in Vo2max or 6-min work capacity on a rowing ergometer at sea level. In contrast, 9 control rowers training at sea level increased Vo2max by 4 (0-8)% and work capacity by 3 (0-11)% (median and range). In rowers emphasizing endurance training during a summer of competitive rowing (n=9), Vo2max and work capacity increased by 6 (0-13)% and 3 (-1-6)%, respectively and no significant changes were noted in rowers performing interval training (n= 9). Exhaustive rowing on an ergometer was characterized by elevated plasma adrenaline, noradrenaline (n=13) and lactate (n=14) (to 19 (11-31), 74 (50-109) nmol l1 and 15 (11-22) mmol-I1, respectively). In heavyweight rowers (n=11), blood volume was 7.0 (5.9-8.3) litres, left ventricular wall thickness 13 (11-15) mm and end-diastolic diameter 57 (54-66) mm (n=11). This study demonstrated an elevated blood volume in rowers as well as myocardial hypertrophy and large internal heart diameters. In well-trained rowers, endurance training is superior to interval training for elevating Vo2max and work capacity, but high-altitude training does not contribute to increasing Vo2max or work capacity at sea level.

Notes: The aim of the study was to examine the time course of changes in pressure pain threshold (PPT), visual analogue scale (VAS) pain and tenderness scores, McGill Pain Questionnaire (MPQ) descriptors, pain areas, skin temperature and mean arterial pressure (MAP) following intensive eccentric exercise. In 11 healthy male subjects, eccentric exercise of the first dorsal interosseous muscle (FDI) of the right hand with 114% maximum voluntary contraction weight (MVC) was used to induce post-exercise muscle soreness (PEMS) in the right hand, while the left hand served as a control. At 24 h to 48 h all the pain profiles indicated the presence of PEMS in the right hand when compared to before exercise (P〈0.05). MPQ and pain area assessments also indicated PEMS immediately after the exercise, while the pain assessment by PPT and tenderness VAS showed insignificant pain immediately after the exercise. Skin temperature measured in the first web space of the hand did not change at any time. MAP was significantly reduced at 48 h. It is concluded that eccentric exercise of a small hand muscle is followed by PEMS and a reduced MAP after 48 h that may suggest a role of central mechanisms in the PEMS, thereby giving further insight into clinical aspects of muscle pain.

Notes: Objective To evaluate the predictive values of fetal fibronectin, bacterial vaginosis, endotoxin and cervical length for preterm birth (〈 35 and 〈 37 weeks) and neonatal morbidity in twin pregnancies.Participants One–hundred and twenty–one women with twin pregnancies recruited into a prospective longitudinal study at three antenatal clinics in the southwest of Sweden.Methods Cervical or vaginal fluid was sampled and determined for fetal fibronectin (〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:14700328:BJO1398:ges" location="ges.gif"/〉 0.05 μg/mL was used as cutoff), endotoxin (〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:14700328:BJO1398:ges" location="ges.gif"/〉 100 pg/mL) and bacterial vaginosis (presence of clue cells) at two week intervals from 24 to 34 weeks of gestation. The cervical length was measured with transvaginal sonography at the same time intervals.Main outcome measures Occurrence of preterm birth (〈 35 and 〈 37 weeks of gestation) and neonatal morbidity.Results All positive fetal fibronectin samples obtained at screening between 24 and 34 weeks predicted birth 〈 35 weeks (RR 18.0; 95% CI2.2–145.9). A positive fetal fibronectin at 28 weeks of gestation predicted delivery 〈 35 weeks (RR 6.3; 95% CI 2.6–15.1) with a sensitivity, specificity, positive and negative predictive value of 50.0, 92.0, 62.5 and 87.3%, respectively. An independent association between fetal fibronectin at 28 weeks and preterm birth (〈 35 weeks) was verified with logistic regression (P= 0.03). A positive fetal fibronectin at 28 weeks of gestation predicted neonatal morbidity (RR 5.1; 95% CI 2.4–11.0) and a longer period of care at the neonatal intensive care unit. The predictive power of cervical sonography was generally low but cervical length (cutoff 〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:14700328:BJO1398:les" location="les.gif"/〉 33 mm) measured at 28 weeks of gestation was significantly associated with birth 〈 37 weeks (RR 2.2; 95% CI 1.1–4.2). The presence of endotoxin correlated to bacterial vaginosis, but these tests were not significantly related to preterm birth or neonatal morbidity.Conclusions Fetal fibronectin predicted preterm birth and neonatal morbidity in twin pregnancies. The predictive value of cervical length determinations was low. Endotoxin and bacterial vaginosis had no predictive power for preterm delivery in this study.

Notes: In a number of studies it has been shown that psychological factors in general and specifically emotional factors can be correlated to changes in immunological function and defence mechanisms. Although the mediating pathways between the central nervous system and the immune system still remain unclear, it is known that some of the‘classical stress hormones’such as cortisol and catecholamines have modulatory effects on different immunological parameters. In this investigation we wished to study the effect of brief hypnotically induced emotional States on monocyte chemotaxis and endocrinological parameters. Eleven highly hypnotically susceptible volunteers were, while in a deep trance, given suggestions to re-experience earlier life experiences involving intense anger and depression in random order. Before concluding hypnosis subjects were given suggestions to re-experience a feeling of happiness and well-being. Monocyte chemotactic activity in sera and serum levels of cortisol, as well as venous plasma levels of the catecholamines epinephrine, norepinephrine. DOPA and DOPAC. were measured before hypnosis, after each emotional stale and immediately after hypnosis. The results showed a significant difference (P〈0.02) in chemotactic activity between the angry and the depressed emotional states, the depressed state exhibiting a decreased chemotactic index compared with the angry slate. Chemolactic index after the happy relaxed emotional state also showed a significant (P〈0.01) increase compared with both chemotactic index before hypnosis and chemotactic activity after the angry and depressed state. Though there were significant differences between emotions and between emotions and the before-hypnosis-concision, no clear-cut significant differences between the emotional slates of anger and depression could be detected for serum cortisol levels and catecholamine plasma levels. Significant positive correlations (P〈0.01) for differences in chemotactic activity and differences in plasma DOPA levels between emotional states was found. When investigated in vitro, DOPA did not in itself exhibit monocyte chemotactic properties. No other significant correlations between differences in chemotactic activity and other endocrinological parameters could be detected. Soluble interleukin-2 receptors in serum were also measured. No significant differences were found.

Notes: This study was performed to investigate the effects of intermittent hypoxic exposure on blood and exercise parameters. Eight sea level residents were exposed to 2 h daily stimulus to 4100 m altitude in a hypobaric chamber for a total of 14 days. Exercise performance was evaluated at sea level before and after the hypoxic stimulation. Blood samples were obtained before, during, and at time points up to 14 days after the hypoxic exposure. No changes were observed in haemoglobin, haematocrit, reticulocytes, serum transferrin receptors, or EPO levels in the blood. Submaximal cycle (150 W) ergometer exercise corresponded to a oxygen uptake of 1.9±0.1 and 1.9±0.1 L min−1 before and after the intermittent altitude exposure, respectively. At maximal exercise the workloads attained were 343±17 and 354±27 W before and after the exposure, with corresponding oxygen uptakes of 4.0±0.2 and 4.2±0.2 L min−1. It is concluded that intermittent hypoxic exposure to 4100 m altitude for 2 h daily and a total of 14 days does not affect exercise capacity.

Notes: Tobacco seedlings were grown in nutrient agar at a range of ammonium nitrate concentrations either without added sucrose, or with 100 mol m–3 sucrose. In the absence of added sucrose, nitrogen-limited plants had increased levels of glucose, fructose and sucrose, decreased chlorophyll, decreased protein, and decreased Rubisco activity, but the level of the transcript for the small subunit of Rubisco (RbcS) did not decrease compared with nitrogen-sufficient plants. When sucrose was added to nitrogen-sufficient seedlings, there was an increase of sucrose, glucose and fructose in the leaves, growth was increased, and the chlorophyll and protein content, Rubisco activity, and the RbcS transcript level did not change. When sucrose was added to nitrogen-limited seedlings, there was a further increase of sucrose, glucose and fructose, growth was not increased, and there was a further decrease of chlorophyll, protein and Rubisco activity, and a marked decrease of the RbcS transcript level. To check that the decrease of the RbcS transcript level was not an indirect effect due to changes of nitrogen metabolites after adding sugars, glucose was added to Chenopodium cells in the presence and absence of glutamine or azaserine. Changes of glutamine that suffice to increase and decrease the level of the transcript for nitrate reductase (Nia) do not affect the RbcS transcript concentration, and glucose addition still led to a decrease of the RbcS transcript level when the internal glutamine concentration was high. Tobacco seedlings were also grown in nutrient agar at a range of phosphate concentrations either without added sucrose, or with 100 mol m–3 sucrose. Phosphate-limited seedlings did not show a decrease of chlorophyll, protein, Rubisco activity, or the level of the RbcS transcript, compared with phosphate-sufficient seedlings. The addition of sucrose to phosphate-limited plants led to a similar increase of sugars to that seen after adding sucrose to nitrogen-limited seedlings, but did not alter chlorophyll, protein, Rubisco activity, or the level of the RbcS transcript. The addition of sucrose to phosphate-limited plants led to a slight increase of the level of the transcript for nitrate reductase (Nia), increased nitrate reductase activity, and a marked increase of the amino acid content. Phosphate limitation led to an increased level of the transcript for the regulatory subunit of ADP glucose pyrophosphorylase (AgpS2), and this response was strengthened when sucrose was added. The regulation of AgpS2 expression by phosphate and sucrose was further investigated by feeding sucrose and phosphate to detached source leaves via the transpiration stream. The level of the AgpS2 transcript decreased after feeding phosphate and increased after feeding sucrose, and the effect of sucrose was antagonised by phosphate. It is concluded that the response to sugar signalling is modulated by nitrogen and phosphate in a gene-specific manner. The significance of these results for understanding the visual phenotype of nitrogen- and phosphate-limited plants, and the response of photosynthesis and starch synthesis to the plant nutrient status is discussed.

Notes: These experiments investigate events involved in triggering sugar accumulation in the cold in tubers of Solanum tuberosum L. cv. Desirée. Sugar content, 14C-glucose metabolism, metabolite levels and activities of sucrose phosphate synthase (SPS) and starch-degrading enzymes were followed after transfer to 4°C. (i) Net sucrose accumulation began between 2 and 4 d. By 10 d, reducing sugars were also increasing. From 20 d onwards, sugar accumulation slowed. Sucrose fell, but reducing sugars continued to increase. (ii) To measure unidirectional sucrose synthesis, U-[14C]glucose was injected into tubers after various times at 4°C. The tubers were then incubated for 6 h. After 1 d at 4°C, both the absolute and the relative (expressed as a percentage of the metabolized label) rates of sucrose synthesis decreased compared to those at 20°C. Between 2 and 4 d at 4°C, labelling of sucrose increased 3-fold, to over 60% of the metabolized label. This high rate was maintained for up to 50 d in cold storage. When tissue slices were incubated with 2.5 mol m−3 U-[14C]glucose, the rate of labelling of sucrose in slices from 6 d cold-stored material was higher than in slices from warm-stored material, irrespective of whether the incubation occurred at 4°C or at 20°C. (iii) Hexose-phosphates increased during the first day after transfer to 4°C. Their levels fell during the next 3 d, as sucrose synthesis increased. They then rose (until 20 d) and fell, in parallel with the rise and decline of sucrose levels. UDPglucose remained unaltered during the first 4 d, and then increased and decreased in parallel with sucrose. (iv) SPS activity assayed in optimal conditions and the total amount of SPS protein did not change. However, when assayed in the presence of phosphate and limiting substrate concentrations, activity rose 3–5-fold between 2 and 4 d. (v) Amylases and phosphorylases were investigated using zymograms to separate isoforms. Phosphorylases did not change. Between 2 and 4 d at 4°C, a new amylolytic activity appeared. (vi) Estimates of the specific activity of the phosphorylated intermediates and the absolute rate of sucrose synthesis (calculated from the 14C-labelling data and metabolite analysis) showed that changed kinetic properties of SPS and decreased levels of hexose-phosphate are accompanied by a 6–8-fold stimulation of sucrose synthesis. They also show that the final level of sugar is partly determined by a cycle of sugar synthesis and degradation. (vii) It is concluded that the onset of sugar accumulation in cold-stored tubers is initiated by a change in the kinetic properties of SPS and the appearance of a new amylolytic activity. It is discussed how other factors, including hexose-phosphate levels and subcellular compartmentalization, could also influence the final levels of sugars by altering the balance of sugar synthesis and remobilization.