bluuebunny/crossref_metadata_2025_split huggingface dataset:
Towards an understanding of self‐reports of sleep
Authors: Gehrman Philip , Matt Georg E. , Turingan Maria , Dinh Quyen , Ancoli‐Israel Sonia 
Published: March 2003

SummarySleep research has made extensive use of self‐report measures relying on a response format that requires respondents to provide single, specific numerical estimates. The cognitive processes involved in storing and retrieving sleep‐related information allow only approximate numeric estimates of sleep behavior. Based on a fuzzy set model of survey responses, a response format is proposed to better capture the inherent vagueness of quantitative estimates of sleep behavior. Ninety‐three adults (mean age 29.3 years) participated in two interviews, 1 month apart, consisting of questions about health‐related behaviors. Questions were asked in both traditional point estimate and fuzzy response formats. A subset of questions was repeated at the end of each interview to examine test–retest reliability. Subjects filled out daily diaries each morning during the month between interviews. Quantitative estimates of usual sleep behavior were found to be highly reliable. Point estimates differed significantly from fuzzy boundary estimates. Differences between lower and upper boundary estimates indicated substantial ranges in estimates of usual sleep: total sleep time (6–8.2 h), sleep latency (26–44 min), bed time (11:25 PM–12:56 AM) and waking time (7:24–8:39 AM). Mean diary‐recorded bed and waking times fell between the lower and upper boundary estimates in more than 53% of cases, and between the lower and upper extreme estimates in more than 92% of cases. Fuzzy response formats provide an opportunity to report more completely what can be recalled about sleep behavior. They also provide a useful framework for better understand the meaning of traditional point estimate formats.
Insomnia and global sleep dissatisfaction in Finland
Authors: Ohayon Maurice M. , Partinen Markku 
Published: March 2003

SUMMARYThe purpose of this study is to assess the prevalence of insomnia symptoms and diagnoses in the general population of Finland. A total of 982 participants, aged 18 years or older and representative of the general population of Finland, were interviewed by telephone using the Sleep‐EVAL system. The participation rate was 78%. The questionnaire included the assessment of sleep habits, insomnia symptomatology according to Diagnostic and Statistical Manual of Mental Disorders‐IV (DSM‐IV) and International Classification of Sleep Disorders (ICSD), associated and sleep/mental disorders and daytime consequences. The overall prevalence of insomnia symptoms occurring at least three nights per week was 37.6%. Difficulty initiating sleep were mentioned by 11.9% of the sample, difficulty maintaining sleep by 31.6%, early morning awakenings by 11.0% and non‐restorative sleep by 7.9% of the sample. Global dissatisfaction with sleep was found in 11.9% of the sample. Daytime consequences (fatigue, mood changes, cognitive difficulties or daytime sleepiness) were reported by 39.9% of participants with insomnia symptoms and 87.6% of those with sleep dissatisfaction. A deterioration of sleep in summer or winter was associated with more complaints of sleep dissatisfaction. Prevalence of any DSM‐IV insomnia diagnosis was 11.7%. More specifically, DSM‐IV diagnosis of primary insomnia had a prevalence of 1.6% and DSM‐IV diagnosis of insomnia related to another mental disorder was at 2.1%. Insomnia was a symptom of another sleep disorder in about 16% of cases and of a mental disorder in about 17% of cases. As reported in other Nordic studies, sleep quality was worse in summer. Insomnia symptomatology was common and was reported by more than a third of Finnish participants. Compared with other European countries studied with the same methodology (France, the UK, Germany, and Italy), the prevalence of DSM‐IV insomnia diagnosis was 1.5 to two times higher in Finland.
The ontogeny of mammalian sleep: a reappraisal of alternative hypotheses
Authors: Frank Marcos G. , Heller H. Craig 
Published: March 2003

SUMMARYNewborn mammals spend as much as 90% or more of their time in a sleep state characterized by frequent twitches, rapid eye movements (REMs), and irregular respiratory cycles. These motor and respiratory patterns resemble the phasic motor/respiratory components of adult REM sleep, and as a consequence, this sleep state is traditionally viewed as an immature form of REM sleep. An alternative view is that a significant portion of what has been called REM sleep in these species is a form of spontaneous activity typical of the immature nervous system. In this review, we compare and contrast these two opposing views about the ontogenetic origins of REM sleep, and review the evidence most often cited to support the idea that REM sleep is present in newborn altricial mammals. Critical review of this evidence indicates that REM sleep may not be present at birth in these species; rather, it appears that all mammals early in development exhibit spontaneous, dissociated activity that progressively becomes organized into the distinct states of REM and non‐rapid eye movement sleep.
Characterization of nuclease‐resistant ribozymes directed against hepatitis B virus RNA*
Authors: Morrissey D. V. , Lee P. A. , Johnson D. A. , Overly S. L. , McSwiggen J. A. , Beigelman L. , Mokler V. R. , Maloney L. , Vargeese C. , Bowman K. , O'Brien J. T. , Shaffer C. S. , Conrad A. , Schmid P. , Morrey J. D. , Macejak D. G. , Pavco P. A. , Blatt L. M. 
Published: March 2003

summary. Hepatitis B virus (HBV) is responsible for > 350 million cases of chronic hepatitis B worldwide and 1.2 million deaths each year. To explore the use of ribozymes as a novel therapy for HBV infection, nuclease‐resistant ribozymes that target highly conserved regions of HBV RNA were screened in cell culture. These synthetic ribozymes have the potential to cleave all four major HBV RNA transcripts and to block the HBV lifecycle by cleavage of the pregenomic RNA. A number of the screened ribozymes demonstrate activity in cell culture systems, as measured by decreased levels of HBV surface antigen, HBV e antigen and HBV DNA. In addition, a lead anti‐HBV ribozyme maintains activity against a lamivudine‐resistant HBV variant in cell culture. Treatment of HBV transgenic mice with lead anti‐HBV ribozymes significantly reduced viraemia compared with saline‐treated animals and was as effective as treatment with lamivudine. In conclusion, the therapeutic use of a ribozyme alone or in combination with current therapies (lamivudine or interferons) may lead to improved HBV therapy.
Aetiology, clinical course and outcome of sporadic acute viral hepatitis in pregnancy*
Authors: Khuroo M. S. , Kamili S. 
Published: March 2003

summary. Hepatitis E causes large‐scale epidemics in endemic areas. The disease, during epidemics, has increased incidence and severity in pregnant women. Sporadic acute viral hepatitis (AVH) is common in endemic areas. The relationship of sporadic AVH and pregnancy has not been well studied. Over a 3‐year period we prospectively studied 76 pregnant women and 337 non‐pregnant women of childbearing age with sporadic acute viral hepatitis for aetiology, clinical course and outcome of disease. The aetiology in sporadic AVH was hepatitis A virus (HAV) in six (1.5%), hepatitis B virus (HBV) in 62 (15%), hepatitis C virus (HCV) in seven (1.7%), hepatitis D virus (HDV) co‐infection in six (1.5%), hepatitis E virus (HEV) in 205 (49.6%), and hepatitis non‐A‐to‐E (HNAE) in 127 (30.7%). Sixty‐five (85.5%) pregnant women and 140 (41.5%) nonpregnant women had hepatitis E. The proportion of pregnant women was 31.7% in HEV group and 5.3% in non‐HEV group [P < 0.001; OR=8.3 (95%C1 4.2–16.3)]. The prevalence of HEV in pregnant women in first trimester (76.9%), second trimester (88.9%), third trimester (83.8%) and puerperium (100%) did not differ significantly (P=0.09). Forty‐seven (61.8%) of the 76 pregnant women developed fulminant hepatic failure (FHF), 69.2% in HEV group and 10% in non‐HEV group (P < 0.001). Thirty‐four (10.1%) nonpregnant women developed fulminant hepatic failure, 10% in HEV group and 9.7% in non‐HEV group (P=0.86). FHF had occurred in four (40%) of 10 patients with HE in first trimester as against 41 (74.5%) of 55 patients in second trimester and beyond (P=0.015). Amongst the major complications of fulminant hepatic failure, cerebral oedema (53.2%) and disseminated intravascular coagulation (21.3%) occurred more often in pregnant women than in nonpregnant women (29.4% and 2.8%; P=0.03 and 0.016, respectively) while infections occurred more often in nonpregnant women (36.1%) than in pregnant women (10.6%; P=0.003). Fifty (61.7%) patients with FHF died [25 (53.2%) pregnant women and 25 (69.5%) nonpregnant women (P=0.06)]. Cerebral oedema and HEV aetiology were independent variables of survival in patients with FHF. Patients with cerebral oedema had worse prognosis and patients with HEV aetiology had best chances of survival. Hence HEV was the most common cause of sporadic AVH in this endemic area. High proportion of pregnant women and increased severity of disease in pregnancy were limited to patients with hepatitis E. Sporadic AVH caused by agents other than HEV did not show any special predilection to or increased severity in pregnancy. FHF in pregnant women caused by HEV was an explosive disease with short pre‐ encephalopathy period, rapid development of cerebral oedema and high occurrence of disseminated intravascular coagulation and may represent a severe manifestation of a Schwartzmann‐like phenomenon.
The safety and tolerability of daily infergen plus ribavirin in the treatment of naíïve chronic hepatitis C patients
Authors: Pockros P. J. , Reindollar R. , McHutchinson J. , Reddy R. , Wright T. , Boyd D.G. , Wilkes L.B. 
Published: March 2003

summary.  The treatment of chronic hepatitis C patients was enhanced when the combination of interferon alfa‐2b and ribavirin was shown to be safe and more effective than interferon monotherapy. To date, no published reports have addressed the use of consensus interferon (CIFN) when combined with ribavirin. We conducted a pilot study to compare the safety and tolerability of daily CIFN plus ribavirin to CIFN monotherapy for the initial treatment of chronic hepatitis C patients. Forty subjects were randomized to two treatment groups; CIFN 9 μg daily, or CIFN 9 μg daily plus ribavirin 1000 or 1200 mg daily. All subjects received 48 weeks of therapy except for nongenotype 1 subjects in the combination treatment group who received only 24 weeks of therapy. The results show that at baseline, age, gender, risk factors, race, RNA titres, and liver histology were not different between the two groups. The proportion of subjects with genotype 1 infection was 50% (10/20) and 55% (11/20) for the monotherapy and combination therapy groups, respectively. Fifty (10/20) and sixty‐five (13/20) per cent of subjects in the monotherapy and combination therapy groups exhibited a 2‐log or greater decrease in viral titre at week 12 (P = NS). Using intent‐to‐treat analysis, 20% and 40% of enrolled subjects exhibited a sustained viral response in the monotherapy and combination therapy groups, respectively (P = NS). The proportion of subjects requiring dose reduction was 55% (11/20) and 65% (13/20), respectively. Study discontinuations for any reason were 25% (5/20) and 35% (7/20) for the monotherapy and combination groups, respectively. Discontinuations due to adverse events related to study drug were 20% (4/20) and 25% (5/20), respectively. A total of four serious adverse events occurred, two in each treatment group, only one of which was determined to be study‐drug related. It is concluded that the safety and tolerability profiles of the two treatments were similar suggesting that daily dosing of CIFN may be difficult to tolerate resulting in discontinuation of therapy in a significant proportion of patients. The combination regimen resulted in a trend towards a higher viral response rate than monotherapy treatment. These data suggest that CIFN may be safely combined with ribavirin and may enhance the sustained response rate but is not well tolerated in US patients when given in a daily dosing regimen.
The use of marked bait in studies of the territorial organization of the European Badger (Meles meles)
Authors: Delahay R. J. , Brown J. A. , Mallinson P. J. , Spyvee P. D. , Handoll D. , Rogers L. M. , Cheeseman C. L. 
Published: March 2003

ABSTRACTBait‐marking is a widely used technique for determining the territorial configuration of social groups of the European Badger (Meles meles). Applications include ecological research and applied wildlife management problems. Bait laced with indigestible plastic pellets is fed to Badger social groups, and the markers are identified in subsequent defecations. Feeding a unique colour and/or shape of pellet to each social group allows the origin of droppings to be assigned. This method is particularly suited to Badgers because they mark their territorial boundaries with communal latrines. In this paper the technique is described in detail for the first time in the scientific literature. Data from sequential visits to latrines during the survey period showed significant short‐term variation in the number of marked droppings counted at individual latrines. This suggests that counting marked droppings may be of limited value in quantifying defecation rates and latrine use. However, counts of droppings at latrines could be useful if repeated over time and/or grouped into broad categories. Bait marking does provide reliable data for the estimation of territorial boundaries between Badger groups, although it is labour intensive and time‐consuming, with the best results obtained by experienced fieldworkers.
Lessons from lean beasts: conservation biology of the mustelids
Authors: Bright Paul W. 
Published: March 2003

ABSTRACTWhat features of the mustelids might yield insight into issues of general importance for conservation and ecology? This review focuses attention on correlates of threat, intra‐guild competition and reintroductions. Using the IUCN classification of the status of mustelid species, I constructed a statistical model of correlates of threat. This suggested that otters and martens, and mustelids with small distributional range sizes, were the most threatened. Whether or not a species was hunted and its habitat specificity did not correlate with threat. This analysis should be treated as indicative only, because the response variable (threat) was not totally independent of the explanatory variables. There is growing evidence that intra‐guild predation influences mustelids. In Scotland, there is some evidence for spatial segregation between Pine Martens and Red Foxes (a potential predator). Pine Marten relative abundance was higher in woodland interior than woodland edge. Red Foxes were equally abundant in woodland edge and interior. However, habitat fragmentation (woodland patch size) was the strongest correlate of relative abundance of both species. Research on mustelids has demonstrated the importance of appropriate release techniques during reintroductions. It has also shown that reintroductions of small numbers of animals can be successful, provided that they are conducted in high quality habitats. The implication is that habitat suitability assessments need to be given high priority. In this respect, research in Britain suggests that inferring habitat needs from areas of relict distribution may lead to highly misleading conclusions.
Pteridine fluorescence for age determination of Anopheles mosquitoes
Authors: Wu D. , Lehane M. J. 
Published: March 2003

SummaryThe age structure of mosquito populations is of great relevance to understanding the dynamics of disease transmission and in monitoring the success of control operations. Unfortunately, the ovarian dissection methods currently available for determining the age of adult mosquitoes are technically difficult, slow and may be of limited value, because the proportion of diagnostic ovarioles in the ovary declines with age. By means of reversed‐phase HPLC this study investigated the malaria vectors Anopheles gambiae and An. stephensi to see if changes in fluorescent pteridine pigments, which have been used in other insects to determine the age of field‐caught individuals, may be useful for age determination in mosquitoes. Whole body fluorescence was inversely proportional to age (P < 0.001, r2 > 91%) up to 30 days postemergence, with the regression values: y = 40580–706x for An. gambiae, and y = 52896–681x for An. stephensi. In both species the main pteridines were 6‐biopterin, pterin‐6‐carboxylic acid and an unidentified fluorescent compound. An. gambiae had only 50–70% as much fluorescence as An. stephensi, and fluorescent compounds were relatively more concentrated in the head than in the thorax (ratios 1 : 0.8 An. gambiae; 1 : 0.5 An. stephensi). The results of this laboratory study are encouraging. It seems feasible that this simpler and faster technique of fluorescence quantification could yield results of equivalent accuracy to the interpretation of ovarian dissection. A double‐blind field trial comparing the accuracy of this technique to marked, released and recaptured mosquitoes is required to test the usefulness of the pteridine method in the field.
Evaluation of insecticide‐treated cattle as a barrier to re‐invasion of tsetse to cleared areas in northeastern Zimbabwe
Authors: Warnes M. L. , Van Den Bossche P. , Chihiya J. , Mudenge D. , Robinson T. P. , Shereni W. , Chadenga V. 
Published: March 2003

SummaryA field trial in Zimbabwe investigated the efficacy of insecticide‐treated cattle as a barrier to prevent the re‐invasion of tsetse, Glossina morsitans and G. pallidipes (Diptera: Glossinidae), into cleared areas. The original tsetse barrier consisted of insecticide‐treated odour‐baited targets, at an operational density of four to five targets per km2, supported by insecticide‐treatments of cattle with either deltamethrin dip (Decatix®, Coopers) at two‐weekly intervals, or deltamethrin pour‐on (Spoton®, Coopers) at monthly intervals, in a band ≈ 20 km wide from the re‐invasion front. Tsetse catch, and trypanosomiasis incidence in nine sentinel herds was recorded for 7–8 months, respectively, before the targets were removed, leaving only the insecticide treatment of the local cattle to stem the re‐invasion of tsetse.After the removal of the target barrier, the tsetse readily invaded the trial area and the incidence of trypanosomiasis in sentinel herds increased, while their PCVs decreased. After seven months without the targets in place, trypanosomiasis prevalence in the local stock had reached alarmingly high levels; the trial was terminated prematurely and the target barrier re‐deployed. Immediately after the re‐deployment of the target barrier, the tsetse catch in the trial area reverted to acceptable levels along the re‐invasion front, and trypanosomiasis incidence in the sentinel cattle decreased.It is concluded that, under the conditions of the field trial, the insecticidal treatment of local cattle did not in itself form an effective barrier to tsetse re‐invasion. By contrast, the target barrier performed as was predicted by mathematical and experimental analysis, and readily cleared the tsetse infestation and reduced trypanosomosis incidence in the trial area.
Risk factors in habitats of the tickIxodes ricinusinfluencing human exposure toEhrlichia phagocytophilabacteria
Authors: Walker A. R. , Alberdi M. P. , Urquhart K. A. , Rose H. 
Published: March 2003

SummaryIxodes ricinusL. (Acari: Ixodida) were sampled during 1996–99 in southern Scotland, on vegetation using cloth drags, on humans by removal from clothing and on roe deer (Capreolus capreolusL.) by searching legs of culled deer. Developmental microclimate was recorded by automatic recorders and questing microclimate by portable instruments during tick collections. Ticks and deer were examined for infection withEhrlichia phagocytophilabacteria (Rickettsiales) using microscopy and polymerase chain reaction. This pathogen causes tick‐borne fever of sheep in Europe and human granulocytic ehrlichiosis in North America, but in Europe human clinical ehrlichiosis due toE. phagocytophilahas not been recorded despite serological evidence of exposure.Among three types of habitat, coniferous woodland was most infested with questing ticks (560 ticks/km of drag; mean numbers collected on long trousers: 24.3 larvae, 13.5 nymphs and 0.8 adult ticks/km walked), deciduous woodland had slightly lower infestation (426 ticks/km drag) and upland sheep pasture had much lower infestation (220 ticks/km drag). Of the three main vegetation types, bracken was least infested (360 ticks/km drag), ericas most (430 ticks/km drag) and grassland had intermediate infestation density (413 ticks/km drag). Questing and developmental microclimates were poor predictors of exposure within these habitats, except lower infestation of pastures was attributed to greater illumination there. Collectors who walked a total of 300 km through all habitats (taking 360 h in all seasons), wearing cotton trousers hanging outside rubber boots, were bitten by only four nymphs and 11 larvae ofI. ricinus(but no adult ticks). There was a negative correlation between densities of deer and ticks collected, although presence of deer remains a major indicator of exposure.The proportion of infected ticks was fairly uniform at four sites studied. Overall prevalence ofE. phagocytophilainI. ricinuswas 3.3% in nymphs (40/1203) but only ∼1.5% in adults of both sexes (although males do not bite). It was estimated that nymphs ofI. ricinusgave 4.4% probability of one infected bite/person/year (for occupational exposure during this research) due to presence in all seasons and habitats, their human biting rate of 0.011 nymphs/h or 0.013 nymphs/km and widespread infection withE. phagocytophila.The frequency distribution of intensity of infection in ticks was approximately normal (mean 98 morulae/nymph infected), thus there is a high risk of receiving a high dose from any one infected tick bite.
The effect of a ‘don't know’ option on test scores: number‐right and formula scoring compared
Authors: Muijtjens  , Mameren H van , Hoogenboom  , Evers  , Vleuten C P M van der 
Published: March 2003

ObjectivesIn multiple‐choice tests using a `don't‐know' option the number of correct minus incorrect answers was used as the test score (formula scoring) in order to reduce the measurement error resulting from random guessing. In the literature diverging results are reported when comparing formula scoring and number‐right scoring, the scoring method without the don't‐know option.DesignTo investigate which method was most appropriate, both scoring methods were used in true–false tests (block tests) taken at the end of a second‐ and third‐year educational module (block). The students were asked to answer each item initially by choosing from the response options true, false or don't know, and secondly to replace all don't‐know answers by a true–false answer.SettingMaastricht University, The Netherlands.SubjectsMedical students.ResultsThe correct scores for the don't‐know answered items were found to be 4·5% and 5·9%, respectively, higher than expected with pure random guesswork. This represents a source of bias with formula scoring, because students who were less willing to guess obtained lower scores. The average difference in the correct minus incorrect score for the two scoring methods (2·5%, P < 0·001, and 3·4%, P < 0·001, respectively) indicates the size of the bias (compare: the standard deviation of the score equals 11%). Test reliability was higher with formula scoring (0·72 vs. 0·66 and 0·74 vs. 0·66), but the difference decreased when the test was restricted to items which were close to the core content of the block (0·81 vs. 0·77, resp. 0·75 vs. 0·70).ConclusionsIn deciding what scoring method to use, less bias (number‐right scoring) has to be weighed against higher reliability (formula scoring). Apart from these psychometric reasons educational factors must be considered.