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1.
Changes in the seasonal activity of several species of earthworms have been followed in a permanent pasture field for 18 months, 1945–6. The two soil conditions which chiefly determine activity are temperature and moisture. Other factors are the occurrence of an obligatory diapause in the two species Allolobophora nocturna and A. longa , and changes in population in A. chlorotica and Lumbricus terrestris.
Soil temperature and soil moisture also determined the weight of soil thrown up in the form of wormcasts during autumn, winter and spring. It is suggested that only two species, A. nocturna and A. longa , are responsible for wormcasts and that the other four common species present play little or no part in this activity.
At Rothamsted it was found that the previous agricultural history of the field is an important factor in determining the fauna. Old permanent pasture is characterized by a high percentage of A. nocturna and a rather lower percentage of A. caliginosa. Ploughing old permanent pasture and reseeding to grass after 1 or 2 years arable reduces the proportions of A. nocturna and A. caliginosa and increases that of Eisenia rosea. Arable fields have A. chlorotica as the dominant species and pasture fields 2–7 years grass after many years of arable fanning still show a high percentage of A. chlorotica and a low proportion of A. nocturna.
A survey of the Carse of Stirling, Scotland, showed that soil type is also an important factor in determining the earthworm fauna. A. caliginosa was the dominant species on the three soil types studied, but the subdominant species varied. On clay soil, A. longa was subdominant; on loam, A. longa and L. rubellus ; on sandy soil, A. longa, L. rubellus and A. chlorotica. The dominant species of pasture land at Rothamsted, A. nocturna , was not found at Stirling.  相似文献   

2.
The morphology, gill area and branchial formulae of six thalassinidean decapods ( Calocaris macandreae, Jaxea nocturna, Callianassa subterranea, Upogebia stellata, U. deltaura and U. pusilla ) are reported. Additionally, the rarely-encountered Axius stirhynchus receives brief attention. Gill formulae are presented; the simplest arrangements are found in the Callianassidae and Upogebiidae. The deeper-burrowing, deposit-feeding species that are regularly exposed to prolonged periods of hypoxia, i.e. Callianassa subterranea and Jaxea nocturna , had significantly larger gill areas than thalassinideans that occupied more oxygenated burrows ( Upogebia spp., Calocaris macandreae ). The increase in gill area was a result of flattening of the trichobranchiate gill filaments giving rise to a phylloid gill form. It is suggested that the efficiency of gas transfer, and hence diffusing capacity, was enhanced in the phylloid gill by the larger gill area and, because of the reduced cuticle thickness, by the shorter water-haemolymph diffusion distance. The increased diffusion capacity of the phylloid gill is interpreted as a functional adaptation to the more severe physicochemical burrow water conditions experienced by Callianassa subterranea and Jaxea nocturna .  相似文献   

3.
Ruellia nocturna , a large- and night-flowering shrub from Central Somalia is described and illustrated, and its relationship to other large-flowered species occurring in the area is discussed.  相似文献   

4.
Most arthropod burrows show a marked preferred orientation: they are not random in alignment. A recent burrow made by Jaxea nocturna Nardo is compared to three fossil burrows from the Austrian Tertiary. In each system very steep and very flat burrow sections can be distinguished. In three cases, including the Recent one, flat burrow sections dominate in length. In all burrow sections the distribution of trend angles is also not uniform but indicate preferred directions. In those cases where two mean vectors exist their position is nearly orthogonal, in systems with three mean vectors they form angles of nearly 60°. A relationship between these preferred directions to coastline orientation and current direction is likely.  相似文献   

5.
Desmopressin, a synthetic analog of the antidiuretic hormone, is used in the treatment of enuresis nocturna in children and increasingly also in adults. Nocturia in the elderly causes sleeping disorders and is associated with a higher risk of falling and increased mortality. Desmopressin leads to a significant decrement of nocturia and consequently, a better sleep quality and is for this reason increasingly prescribed in the old. Desmopressin causes borderline hyponatremia (130-135 mmol/l) in 15% and severe hyponatremia in 5% of all adult users. Factors that predispose to hyponatremia are a higher dose, age > 65 years, a low-normal serum sodium, a high 24-hour urine volume and co-medication (thiazide diuretics, tricyclic antidepressants, serotonin-reuptake-inhibitors, chlorpromazine, carbamazipine, loperamide, Non-Steroidal-Anti-Inflammatory-Drugs). Hyponatremia is associated with headache, nausea, vomiting, dizziness, and can cause somnolence, loss of consciousness and death. We present two cases where initiation of desmopressin led to hyponatremia, requiring hospitalization. In view of the high risk of desmopressin-associated hyponatremia in the older population, alternative treatment strategies for nocturia must be considered first. If desmopressin is prescribed, strict follow-up of serum sodium levels is necessary.  相似文献   

6.
Backround: Enuresis implies severe stress in affected children, and impairs quality of life and sleep. Children with enuresis experience difficulties in their arousal from sleep, possibly associated with disturbances of the circadian rhythm. In this study, we aimed to evaluate the sleep–wake cycle and sleep disturbances in children with monosymptomatic enuresis nocturna (MEN). Method: The study comprised 70 children with MEN who were admitted to the pediatrics and urology outpatients department and 94 age-matched healthy controls. Parents completed “Strengths and Difficulties Questionnaire,” Children’s Sleep Habits Questionnaire (CSHQ), Children’s Chronotype Questionnaire scale. Results: Children with enuresis had significantly more sleep and psychological problem. Enuresis group reported higher bedtime resistance, parasomnias, breathing-related problems, and daytime sleepiness in CHSQ (p < 0.05). Although circadian preference did not differ statistically between the groups (p > 0.05), sleep duration on school days and awakening and mid-sleep points, both on scheduled and free days, were found to be significantly different in the enuretic group (p < 0.05). In logistic regression analysis, age, sleep period on scheduled days, sleep inertia on scheduled and free days were significant predictor for enuresis. Discussion: Children with enuresis were more likely to experience problematic sleep. This may reflect that enuretic children have impaired sleep–wake cycles, leading to dysregulation of daily functional changes of bladder capacity and related hormones such as ADH. These findings might imply a sleep–wake disturbance in enuresis.  相似文献   

7.
Three burrow systems produced by Jaxea nocturna and one cluster of burrows produced by Upogebia pusilla where investigated in the Bay of Panzano, Northern Adriatic Sea, to determine preferred orientations. The distributions of dip directions differ between both producers. Steep shafts into the consolidated mud followed by large, shallowly inclined tunnels oriented in a manner similar to a spiral are characteristic for Jaxea nocturna burrows. In contrast, the Y-shaped burrows of Upogebia pusilla have entrance shafts that are less steep which are connected by a near-horizontal section, where a blind ending tunnel branches. Orientations of the dominating, shallowly inclined burrow parts are not randomly distributed in either Jaxea or in Upogebia burrows. Three preferred axial orientations with almost equal proportions in each direction are characteristic for the Jaxea burrow from the centre of the bay. This system transforms to a squared structure near the coast, where one direction parallels the shoreline and the other is oriented at right angles to the coast. The latter orientation demonstrates significant constancy in all investigated burrows. Upogebia burrow clusters coincide with the three preferred orientations of the Jaxea burrow from the bay centre, but the proportions of the directions are unequal. Burrow segments connecting the steep entrance shafts in Upogebia are oriented almost parallel to the shoreline, whereas at right angles to the coast the flat blind-ending tunnels incline towards the open sea. The study shows a strong coincidence between empirical and theoretical distributions of the dominating orientations in both species.  相似文献   

8.
A new species of Theletrum is described from the intestine of two palenose morays, Echidna nocturna, collected in Cuajiniquil, Guanacaste Province, Costa Rica. The new species differs from the type species, T. fustiforme Linton, 1910 by having a subspherical pars prostatica, a subspherical seminal vesicle extending anteriorly to the anterior border of the acetabulum, by the presence of a poorly developed hermaphroditic sac, and by having a larger body size. We also report eight additional species of digeneans parasitizing marine fishes in several localities along the Atlantic and Pacific coast of Costa Rica: Bianium simonei, Didymozoinae (metacercariae), Ectenurus virgulus, Hypocreadium myohelicatum, Lecithochirium microstomum, Pseudolecithaster sp., Stephanostomum casum, and Tergestia laticollis. In addition, we present an updated list of helminth parasites of marine fish from Costa Rica and discuss the importance of including parasites as an integral part of biodiversity inventories.  相似文献   

9.
Morning levels of serum melatonin, FSH, LH, prolactin (PRL), progesterone and estradiol were studied by RIA during the ovarian cycle, perimenopause and menopause in 79 healthy women. FSH and LH levels showed a slight nonsignificant increase from the fertile period to perimenopause, exhibiting a significantly greater increase during menopause. PRL, progesterone and estradiol showed parallel changes, reaching lower levels during menopause. Serum melatonin levels decreased with age, attaining minimum levels in menopause. FSH and estradiol were significantly correlated with melatonin in the follicular phase, while in the luteal phase a negative correlation was found between melatonin, progesterone and estradiol. No significant correlations were noted between serum hormone levels during the perimenopausal period. In menopause, as during the follicular phase, melatonin and FSH were negatively correlated. As expected, a significant positive correlation was found between morning serum levels of melatonin and nocturnal urinary excretion of this indoleamine in all groups studied.  相似文献   

10.
The weight of wormcasts thrown on to the surface of eight fields of differing agricultural history depends on the numbers of Allolobophora longa Ude and A. nocturna Evans present and also on the mean size of the individuals of these two species. The weight of wormcasts produced per acre per annum on the different fields varied from 1 to 25 tons and it is calculated that from 4 to 36 tons of soil per acre per annum pass through the alimentary tracts of the total population of earthworms present. The percentage pore space of a soil containing a high population of wormcasting species is much greater than that of a field with a high population of worms which do not produce wormcasts. In two old pastures, the amount of coarse sand relative to silt and clay was found to increase appreciably with depth: this distribution is probably a result of the long-continued activity of earthworms.  相似文献   

11.
This paper explores the extent to which women's work for earnings, education and couple communication over family planning influence current contraceptive use and children ever born in Nepal. Data came from the 1996 Nepal Family Health Survey. The findings indicate that education has a significant positive influence on current use of contraception and a significant negative influence on children ever born. There was virtually no relationship between women working and current use of contraception. However, in full models, there was a significant positive relationship for women who earn cash for work on current use and a significant negative relationship for children ever born. Working alone does not increase contraceptive use or reduce the number of children ever born in Nepal, but earning cash for work does. The husband/couple variables also proved to be important determinants of current use of contraception and children ever born.  相似文献   

12.
Gastroesophageal reflux (GER) is common in those with asthma, with 77% of asthmatics complaining of heartburn, with 41% experiencing reflux-associated respiratory symptoms. Likewise, 24% of those with asthma that is difficult to control have “clinically silent” GER. There are no studies examining nocturnal reflux symptoms in asthmatics. Esophageal dysmotility is also common, and abnormal esophageal acid contact times on 24h esophageal pH tests were found in 82% of asthmatics examined consecutively. Most asthmatics with GER also have abnormal esophageal acid contact times while in the supine position, reflecting sleep time. Endoscopic evidence of esophagitis was found in 43% of asthmatics. Two mechanisms of bronchoconstriction induced by esophageal acid have been proposed: a vagally mediated reflex, by which esophageal acid in the distal esophagus causes reflex bronchoconstriction, and microaspiration. Although there is conflicting evidence, distal esophageal acid causes a decrease in peak expiratory flow rates, an increase in respiratory resistance, and an increase in minute ventilation. If microaspiration is present, there is further augmentation of this airway response. Although only a few studies have been performed in those with nocturnal asthma with GER, one study in a pediatric population showed that esophageal acid infusions caused more airway responses at 04:00 than at 24:00. Also, asthmatic children with nocturnal asthma symptoms have a higher re-flux score, with a positive correlation between reflux score and nighttime-associated wheezing. Despite these findings in children, a study performed in sleeping adults with nocturnal asthma noted no alterations in airflow resistance with esophageal acid, concluding that GER contributed little to the nocturnal worsening of asthma. There are also gastroesophageal circadian issues that may influence GER in asthmatics. Gastric acid secretion peaks at approximately 21:00, and gastric emptying is delayed when a meal is given at 20:00 versus 08:00. Esophageal acid clearance is delayed significantly during sleep, and acid clearance occurs during arousals. Upper esophageal sphincter (UES) pressure also decreases with sleep onset, which may predispose to microaspiration. Further research is needed to clarify what role nocturnal reflux has on nocturnal asthma and airway inflammation and whether circadian rhythm factors alter airway responses to esophageal acid.  相似文献   

13.
Abstract

This paper explores the extent to which women's work for earnings, education and couple communication over family planning influence current contraceptive use and children ever born in Nepal. Data came from the 1996 Nepal Family Health Survey. The findings indicate that education has a significant positive influence on current use of contraception and a significant negative influence on children ever born. There was virtually no relationship between women working and current use of contraception. However, in full models, there was a significant positive relationship for women who earn cash for work on current use and a significant negative relationship for children ever born. Working alone does not increase contraceptive use or reduce the number of children ever born in Nepal, but earning cash for work does. The husband/couple variables also proved to be important determinants of current use of contraception and children ever born.  相似文献   

14.
The objective of this work was to explore Neurofeedback (NFB) effects on EEG current sources in Learning Disabled (LD) children, and to corroborate its beneficial consequences on behavioral and cognitive performance. NFB was given in twenty 30-min sessions to 11 LD children to reduce their abnormally high theta/alpha ratios (Experimental Group). Another five LD children with the same characteristics received a placebo treatment (Control Group). In the Control Group no changes in behavior or EEG current source were observed. In the Experimental Group, immediately after treatment children showed behavioral and cognitive improvements, but current source analysis showed few modifications; however, 2 months after treatment many changes occurred: a decrease in current of frequencies within the theta band, mainly in left frontal and cingulate regions, and enhancement in current of frequencies within the alpha band, principally in the right temporal lobe and right frontal regions, and of frequencies within the beta band, mainly in left temporal, right frontal and cingulate cortex regions. In conclusion, NFB is a possibly efficacious treatment for LD children with an abnormally high theta/alpha ratio in any lead. The changes observed in EEG current sources may reflect the neurophysiological bases of the improvement that children experienced in their behavioral and cognitive activities.  相似文献   

15.
Beat-to-beat parameters of heart rate (HR), intra-arterial blood pressure (BP), central venous pressure, and derived indexes of cardiac output and total peripheral resistance were recorded 18 h/day (from 1800 to 1200 h the following day) in four monkeys (Macaca mulatta) during 20 control days followed by 20 days of atrial demand pacing. The pacing rate was set at approximately 10 beats/min above the fastest hourly average HR recorded during the control period, i.e., sufficient to prevent the normal nocturnal fall in HR. Nocturnal pacing resulted in progressive weekly increases in central venous BP and arterial BP. Analyses of levels and diurnal trends in hemodynamic parameters and cardiac function curves across consecutive 5-day periods of nocturnal pacing revealed a hemodynamic pattern characteristic of high-output heart failure, which progressively increased (week by week) during the early morning hours (0500-0700). Sustained elevated left ventricular work resulting from the prevention of a nocturnal fall in HR may have been responsible for the reduction in cardiac function seen in this experimental model.  相似文献   

16.
Children with attention-deficit/hyperactivity disorder (ADHD) experience difficulties related to emotional reactivity and regulation. The current study examines differences in the emotional reactivity and regulation of children with and without ADHD in the context of their real-life experiences of negative emotion using a novel ecologically valid methodology. Eighty-three 8–12-year-old children (46 ADHD, 38 non-ADHD) participated in the study. Children completed the negative emotion narrative recall task, a novel task whereby children provided a narrative recall of a real-life event where they experienced negative emotion. ANCOVA indicated children with ADHD recalled significantly more overall frustration and intense frustration than children without ADHD. Children with ADHD exhibiting more negative emotional reactivity while recalling negative emotions than children without ADHD. The current study suggests that children with ADHD are uniquely impacted by negative emotional experiences and represents an important step in understanding the emotional reactivity and regulation of children with ADHD.  相似文献   

17.
The dynamics of direct current potentials of the brain was studied in 10-11-year-old children during sustained attention to successive presentation of series of Shulte tables. Children were examined twice: before and after the series of training to fast reading. A gradual increase in the level of direct current potentials during sustained attention was observed. The increase was more pronounced in children with excessive than in children with moderate reactions to the loading. After the series of training to fast reading, the increase in the level of direct current potentials was reduced in both groups. This aftertraining neurophysiological phenomenon was combined with a transformation of psychophysiological characteristics: a decrease in the time of viewing of Shulte tables and increase in the speed of reading. It is suggested that the shifts of direct current potentials reflects the dynamics of intensity of the cerebral energy metabolism.  相似文献   

18.
To validate cholinesterase activity as a biomarker of pesticide exposure, we characterized the tissue distribution (whole body, nervous tissue and crop/gizzard), activity at two seasons of cholinesterase in six different species of earthworms collected in an unpolluted field: Lumbricus terrestris, Lumbricus castaneus, Aporrectodea nocturna, Aporrectodea caliginosa, Allolobophora chlorotica and Aporrectodea rosea. The major part of total cholinesterase activity was found in the nervous tissue while activity in crop/gizzard was weak. The level of the total cholinesterase activity was stable for each species considered throughout the year (spring and autumn). Lumbricus species exhibited three-fold higher specific activity than the others (0.086+/-0.015 U mg(-1) and 0.235+/-0.036 U mg(-1) for Allolobophora or Aporrectodea, and Lumbricus species respectively). This stability of the base level makes cholinesterase activity a useful biomarker for monitoring effects of pesticide under natural conditions. Cholinesterase activity was characterized using different substrates and inhibitors. It seems likely that the cholinesterases are acetylcholinesterases in most species investigated as they preferentially hydrolyzed acetylthiocholine and were inhibited by eserine, but not by tetraisopropyl pyrophoramide (iso-OMPA). Characterization of cholinesterase from Allolobophora chlorotica is uncertain and it cannot be classified as a true AChE.  相似文献   

19.
The purpose of the current study was to examine protopathic stimulant use among children with the symptoms of ADHD but do not have a diagnosis of ADHD. Protopathic or prodromal stimulant use refers to the use of stimulants by children with the symptoms of ADHD prior to a diagnosis of ADHD. In the current study, we examined children with the symptoms of ADHD who received stimulant treatment across time and with respect to several background variables. Our results indicate that these children who receive stimulant treatment without a diagnosis of ADHD are significantly more like to be eventually diagnosed with ADHD than not. Results also indicate that these children who receive stimulant treatment but do not yet have a diagnosis of ADHD are significantly more likely to have insurance that does not pay for diagnostic procedures. These results are discussed in view of treatment.  相似文献   

20.
《Biomarkers》2013,18(6):517-524
Objective: To find the best lead exposure assessment marker for children.

Methods: We recruited 11 children, calculated a cumulative blood lead index (CBLI) for the children, measured their concurrent BLL, assessed their development, and measured their bone lead level.

Results: Nine of 11 children had clinically significant neurodevelopment problems. CBLI and current blood lead level, but not the peak lead level, were significantly or marginally negatively associated with the full-scale IQ score.

Conclusion: Lead exposure at younger age significantly impacts a child’s later neurodevelopment. CBLI may be a better predictor of neurodevelopment than are current or peak blood lead levels.  相似文献   

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