The effects of a split sleep–wake schedule on neurobehavioural performance and predictions of performance under conditions of forced desynchrony

Extended wakefulness, sleep loss, and circadian misalignment are factors associated with an increased accident risk in shiftwork. Splitting shifts into multiple shorter periods per day may mitigate these risks by alleviating prior wake. However, the effect of splitting the sleep–wake schedule on the homeostatic and circadian contributions to neurobehavioural performance and subjective assessments of one’s ability to perform are not known. Twenty-nine male participants lived in a time isolation laboratory for 13?d, assigned to one of two 28-h forced desynchrony (FD) schedules. Depending on the assigned schedule, participants were provided the same total time in bed (TIB) each FD cycle, either consolidated into a single period (9.33?h TIB) or split into two equal halves (2?×?4.67?h TIB). Neurobehavioural performance was regularly assessed with a psychomotor vigilance task (PVT) and subjectively-assessed ability was measured with a prediction of performance on a visual analogue scale. Polysomnography was used to assess sleep, and core body temperature was recorded to assess circadian phase. On average, participants obtained the same amount of sleep in both schedules, but those in the split schedule obtained more slow wave sleep (SWS) on FD days. Mixed-effects ANOVAs indicated no overall difference between the standard and split schedules in neurobehavioural performance or predictions of performance. Main effects of circadian phase and prior wake were present for both schedules, such that performance and subjective ratings of ability were best around the circadian acrophase, worst around the nadir, and declined with increasing prior wake. There was a schedule by circadian phase interaction for all neurobehavioural performance metrics such that performance was better in the split schedule than the standard schedule around the nadir. There was no such interaction for predictions of performance. Performance during the standard schedule was significantly better than the split schedule at 2?h of prior wake, but declined at a steeper rate such that the schedules converged by 4.5–7?h of prior wake. Overall, the results indicate that when the total opportunity for sleep per day is satisfactory, a split sleep–wake schedule is not detrimental to sleep or performance. Indeed, though not reflected in subjective assessments of performance capacity, splitting the schedule may be of some benefit, given its reduction of neurobehavioural impairment at night and its association with increased SWS. Therefore, for some industries that require operations to be sustained around the clock, implementing a split work–rest schedule may be of assistance.     

The effect of consecutive transmeridian flights on alertness,sleep–wake cycles and sleepiness: A case study

ABSTRACT

Travel across time zones disrupts circadian rhythms causing increased daytime sleepiness, impaired alertness and sleep disturbance. However, the effect of repeated consecutive transmeridian travel on sleep–wake cycles and circadian dynamics is unknown. The aim of this study was to investigate changes in alertness, sleep–wake schedule and sleepiness and predict circadian and sleep dynamics of an individual undergoing demanding transmeridian travel. A 47-year-old healthy male flew 16 international flights over 12 consecutive days. He maintained a sleep–wake schedule based on Sydney, Australia time (GMT + 10?h). The participant completed a sleep diary and wore an Actiwatch before, during and after the flights. Subjective alertness, fatigue and sleepiness were rated 4 hourly (08:00–00:00), if awake during the flights. A validated physiologically based mathematical model of arousal dynamics was used to further explore the dynamics and compare sleep time predictions with observational data and to estimate circadian phase changes. The participant completed 191?h and 159 736?km of flying and traversed a total of 144 time-zones. Total sleep time during the flights decreased (357.5?min actigraphy; 292.4?min diary) compared to baseline (430.8?min actigraphy; 472.1?min diary), predominately due to restricted sleep opportunities. The daily range of alertness, sleepiness and fatigue increased compared to baseline, with heightened fatigue towards the end of the flight schedule. The arousal dynamics model predicted sleep/wake states during and post travel with 88% and 95% agreement with sleep diary data. The circadian phase predicted a delay of only 34?min over the 16 transmeridian flights. Despite repeated changes in transmeridian travel direction and flight duration, the participant was able to maintain a stable sleep schedule aligned with the Sydney night. Modelling revealed only minor circadian misalignment during the flying period. This was likely due to the transitory time spent in the overseas airports that did not allow for resynchronisation to the new time zone. The robustness of the arousal model in the real-world was demonstrated for the first time using unique transmeridian travel.     

The effect of motion sickness on the sleep–wake cycle in rats exposed to prenatal hypoxia

This study is a follow-up to our previous research of the phenomenology and mechanisms of motion sickness (MS) and its relationship with changes in the sleep–wake cycle (SWC). We report data on the effect of MS on the SWC in 30-day-old intact rats and those exposed to prenatal hypoxia on days 13 and 19 of gestation. In all animal groups, MS was shown to decrease significantly the waking time and increase that of paradoxical sleep (PS). A link between hypothalamic MS and SWC regulatory mechanisms was revealed, and the role of this teamwork in the development of the sopite syndrome, which may be a sole manifestation of MS in some animals and man, was suggested. It was established that hypoxic exposure on day 19 of gestation had a greater damaging effect on the thalamocortical sleep-regulating structures than that on day 13, when it is only the hypothalamic-hippocampal slow-sleep regulatory systems that were found to be affected. Against this background, MS appreciably suppresses the brain excitatory systems that maintain wakefulness (supposed to be the ascending reticular activating system) and enhances those activating systems that regulate PS. It is exactly prenatal hypoxic exposure of rats on day 19 of gestation that enabled demonstrating the role of the evolutionarily young thalamocortical system in PS control.     

Effects on the prostate of environmental cadmium exposure – A cross-sectional population study in China

To explore possible effects of environmental cadmium exposure on prostate in humans, and the possible relationship of serum sex hormones to occurrence of clinic signs of tissue changes in the prostate, a case-control study was undertaken in the southeast part of China in 1998. A total of 297 male volunteers from a control area and two cadmium-polluted areas were included as subjects in this study. All the subjects were required to answer a questionnaire and to undergo a complete physical examination including digital-rectal examination (DRE). Blood and urine samples were collected. Serum total prostate specific antigen (PSA), total serum testosterone (T), follicle stimulating hormone (FSH) and luteinizing hormone (LH) were measured by radioimmunoassay and enzymeimmunoassay method, respectively. The data of urinary cadmium (U-Cd) and blood cadmium (B-Cd) were obtained by atomic absorption spectrometry (AAS) as an indicator of cadmium body burden. Statistical analysis was applied to investigate a possible relation between cadmium exposure and prostate pathological changes. The results show that there is a clear dose-response relationship between cadmium exposure and the prevalence of cases with abnormal PSA. The blood cadmium content in cases with positive DRE was significantly higher than that of subjects with negative DRE (P<0.05). Significant differences in the level of FSH between cases with positive DRE and the normal subjects were also noted (P<0.05). These results indicate that chronic environmental cadmium exposure is associated with injuries to human prostate. A possible relationship to changes in circulating sex hormones needs further investigation.     

The impact of high-heeled shoes on ankle complex during walking in young women—In vivo kinematic study based on 3D to 2D registration technique

Objective: To explore the accurate in vivo kinematic changes in the ankle complex when wearing low- and high-heel shoes (LHS and HHS, respectively). Materials and methods: Twelve young women were tested unilaterally. Three-dimensional models of the tibia, talus, and calcaneus were first created based on CT scan results. The subjects walked at a self-controlled speed in barefoot, LHS (4 cm), and HHS (10 cm) conditions. A fluoroscopy system captured the lateral fluoroscopic images of the ankle complex. The images of seven key positions in the stance phase were selected, and 3D to 2D bone model registrations were performed to determine the joint positions. The mean of 6 degree of freedom (DOF) range of motions (ROM), joint positions, and angular displacements of the ankle complex during the gait were then obtained. Results: For the talocrural joint, the rotational ROMs of the subjects either in LHS or HHS condition displayed no significant difference from those in barefoot condition. For the subtalar joint, all the rotational ROMs in the HHS condition and the internal/external rotations in the LHS condition significantly decreased compared with those in the barefoot condition. The talocrural joint was positioned significantly more plantarflexed, inverted, internally rotated, and posteriorly seated in all seven poses in HHS condition, compared with those in barefoot condition. Conclusion: HHS mainly affected the rotational motion of the ankle complex during walking. The talocrural joint position was abnormal, and the subtalar joint ROM decreased during the gait in HHS condition. Only a few kinematic changes occurred in LHS condition relative to the barefoot condition.     

The impact of landfilling and composting on greenhouse gas emissions – A review

Municipal solid waste is a significant contributor to greenhouse gas emissions through decomposition and life-cycle activities processes. The majority of these emissions are a result of landfilling, which remains the primary waste disposal strategy internationally. As a result, countries have been incorporating alternative forms of waste management strategies such as energy recovery from landfill gas capture, aerobic landfilling (aerox landfills), pre-composting of waste prior to landfilling, landfill capping and composting of the organic fraction of municipal solid waste. As the changing global climate has been one of the major environmental challenges facing the world today, there is an increasing need to understand the impact of waste management on greenhouse gas emissions. This review paper serves to provide an overview on the impact of landfilling (and its various alternatives) and composting on greenhouse gas emissions taking into account streamlined life cycle activities and the decomposition process. The review suggests greenhouse gas emissions from waste decomposition are considerably higher for landfills than composting. However, mixed results were found for greenhouse gas emissions for landfill and composting operational activities. Nonetheless, in general, net greenhouse gas emissions for landfills tend to be higher than that for composting facilities.     

The effect of sleep on motor skill learning in young badminton players aged 6–9 years

The objective of this study was to examine the effect of sleep on the acquisition of motor skills in young badminton players. Thirteen badminton players, aged 6–9 years (8.0 ± 0.3 years; mean ± SE), practiced the shuttle bouncing drill, and a skill none of the players had prior experience with. After practice sessions, shuttle bouncing performance was immediately tested and then retested 1 week later. We evaluated sleep parameters for 7 consecutive days using actigraphy. Using the median value of sleep efficiency, subjects were divided into two groups: good sleepers and poor sleepers. Good sleepers had shorter sleep latency (p < 0.05), longer wake after sleep onset (p < 0.001), longer total sleep time (p < 0.005), and higher sleep efficiency (p < 0.001) than the poor sleepers. Interestingly, improvement in shuttle bouncing performance was significantly greater in the good sleeper group than that in the poor sleeper group (p < 0.05). In addition, we found that changes in the shuttle bouncing performance positively correlated with sleep efficiency (β = 0.765, p < 0.01) and total sleep time (β = 0.588, p < 0.05) after adjusting for their badminton career. These data suggest that sleep may affect the acquisition of motor skills in young players.

     

The impact of gout on patient’s lives: a study of African-American and Caucasian men and women with gout

Introduction

The aim of this study was to examine the impact of gout on quality of life (QOL) and study differences by gender and race.

Methods

Ten race- and sex-stratified nominal groups were conducted, oversampling for African-Americans and women with gout. Patients presented, discussed, combined and rank-ordered their concerns.

Results

A total of 62 patients with mean age 65.1 years, 60% men, 64% African-American, participated in 10 nominal groups: African-American men (n = 23; 3 groups); African-American women (n = 18; 3 groups); Caucasian men (n = 15; 3 groups); and Caucasian women (n = 6; 1 group). The most frequently cited high-ranked concerns among the ten nominal groups were: (1) effect of gout flare on daily activities (n = 10 groups); (2) work disability (n = 8 groups); (3) severe pain (n = 8 groups); (4) joint swelling and tenderness (n = 6 groups); (5) food restrictions (n = 6 groups); (6) medication related issues (n = 6 groups); (7) dependency on family and others (n = 5 groups); (8) emotional Impact (n = 5 groups); (9) interference with sexual function (n = 4 groups); (10) difficulty with shoes (n = 4 groups); and (11) sleep disruption (n = 4 groups). Compared with men, women ranked the following concerns high more often: problems with shoes (n = 4 versus n = 0 groups); dependency (n = 3 versus n = 2 groups); and joint/limb deformity (n = 2 versus n = 0 group). Compared with Caucasians, African-Americans ranked the following concerns high more often: dietary restrictions (n = 6 versus n = 0 groups); severe pain (n = 6 versus n = 2 groups); gout bringing the day to a “halt” (n = 2 versus n = 0 group); effect on emotional health (n = 4 versus n = 1 groups); and the need for canes/crutches during flares (n = 2 versus n = 0 group).

Conclusions

Gout has a significant impact on a patient’s QOL. Important differences in the impact of gout by gender and race were noted.     

The combined impact of mechanical factors on the wall stress of the human ascending aorta – a finite elements study

Background

Biomechanical factors influence stress in the aortic wall. The aim of this study was to assess how the diameter and shape of the vessel, blood pressure and longitudinal systolic aortic stretching (SAS) caused by the contraction of the myocardium influence stress in the aortic wall.

Methods

Three computational models of the non-dilated aorta and aneurysms of the ascending aorta and aortic root were created. Then, finite elements analyses were carried out. The models were subjected to blood pressure (120 mmHg and 160 mmHg) and longitudinal systolic aortic stretching (0 mm, 5 mm, 10 mm and 15 mm). The influence of wall elasticity was examined too.

Results

Blood pressure had a smaller impact on the stress than the SAS. An increase in blood pressure from 120 mmHg to 160 mmHg increased the peak wall stress (PWS) on average by 0.1 MPa in all models. A 5 mm SAS caused a 0.1–0.2 MPa increase in PWS in all the models. The increase in PWS caused by a 10 mm and 15 mm SAS was 0.2 MPa and 0.4 MPa in the non-dilated aorta, 0.2–0.3 MPa and 0.3–0.5 MPa in the aneurysm of the ascending aorta, and 0.1–0.2 MPa and 0.2–0.3 MPa in the aortic root aneurysm model, respectively. The loss of elasticity of the aneurysmal wall resulted in an increase of PWS by 0.1–0.2 MPa.

Conclusions

Aortic geometry, wall stiffness, blood pressure and SAS have an impact on PWS. However, SAS had the biggest impact on wall stress. The results of this study may be useful in future patient-specific computational models used to assess the risk of aortic complications.

     

Changes in the sleep–wake rhythm,sleep quality,mood, and quality of life of patients receiving treatment for lung cancer: A longitudinal study

Studies on the diurnal sleep–wake rhythm of patients with lung cancer have mostly examined patients cross-sectionally, whereas the effects of lung cancer treatment over time have rarely been considered. Through long-term longitudinal tracking of patients with lung cancer, this study examined changes in their sleep–wake rhythm, sleep quality, anxiety, depressive symptoms, fatigue and quality of life (QoL) at various treatment stages. In addition, factors affecting their QoL were explored. Hierarchical linear modeling was adopted to analyze a convenience sample of 82 patients with lung cancer. The changes in their sleep–wake rhythm, sleep, mood (anxiety, depressive symptoms and fatigue) and QoL were observed at five time points: prior to treatment and at weeks 6, 12, 24 and 48 after the start of the treatment. The effects of sex, age, cancer stage, treatment type, comorbidities and time were controlled to determine the predictors of patients’ QoL. The results showed that patients’ sleep–wake rhythms were poor before treatments. Compared with baseline, the sleep–wake rhythms of the patients significantly improved at week 48, and anxiety significantly improved at weeks 6, 12, 24 and 48. By contrast, their fatigue became exacerbated at weeks 8 and 48. Moreover, QoL improved significantly from week 6 until the end of the treatment period. QoL was negatively affected by poor sleep quality (β = ?0.69, p = 0.00) and depressive symptoms (β = ?2.59, p < 0.001) and positively affected by regular sleep–wake rhythms (β = 0.23, p = 0.001). Therefore, clinical health-care professionals should focus more attention to the fatigue levels of patients with lung cancer before, during and after treatment. Health-care professionals may also need to provide such patients with health education regarding sleep hygiene and with emotional support to assist them in maintaining regular sleep–wake rhythms in order to improve their QoL.     

Temporal evolution of biochar's impact on soil nitrogen processes – a 15N tracing study

Biochar addition to soils has been proposed as a means to increase soil fertility and carbon sequestration. However, its effect on soil nitrogen (N) cycling and N availability is poorly understood. To gain better insight into the temporal variability of the impact of biochar on gross soil N dynamics, two ¹⁵N tracing experiments, in combination with numerical data analysis, were conducted with soil from a biochar field trial, 1 day and 1 year after application of a woody biochar type. The results showed accelerated soil N cycling immediately following biochar addition, with increased gross N mineralization (+34%), nitrification (+13%) and ammonium (NH₄⁺) and nitrate (NO₃⁻) immobilization rates (+4500% and +511%, respectively). One year after biochar application, the biochar acted as an inert substance with respect to N cycling. In the short term, biochar's labile C fraction and a pH increase can explain stimulated microbial activity, while in the longer term, when the labile C fraction has been mineralized and the pH effect has faded, the accelerating effect of biochar on N cycling ceases. In conclusion, biochar accelerates soil N transformations in the short-term through stimulating soil microbial activity, thereby increasing N bio-availability. This effect is, however, temporary.     

The impact of HPV infection on human glycogen and lipid metabolism – a review

Reinterpretation of the Wartburg effect leads to understanding aerobic glycolysis as a process that provides considerable amount of molecular precursors for the production of lipids, nucleotides and amino acids that are necessary for continuous growth and rapid proliferation characteristic for cancer cells.Human papilloma virus (HPV) is a number one cause of cervical carcinoma with 99% of the cervical cancer patients being HPV positive. This tight link between HPV and cancer raises the question if and how HPV impact cells to reprogram their metabolism? Focusing on early phase proteins E1, E2, E5, E6 and E7 we demonstrate that HPV activates plethora of metabolic pathways and directly influences enzymes of the glycolysis pathway to promote the Warburg effect by increasing glucose uptake, activating glycolysis and pentose phosphate pathway, increasing the level of lactate dehydrogenase A synthesis and inhibiting β-oxidation. Our considerations lead to conclusion that HPV is substantially involved in metabolic cell reprogramming toward neoplastic phenotype and its metabolic activity is the fundamental reason of its oncogenicity.     

Seasonal effects on the sleep–wake cycle,the rest–activity rhythm and quality of life for Japanese and Thai older people

Background: The sleep-wake cycle and the rest–activity rhythm are known to change with aging, and such changes have been implicated in higher levels of depression as well as an increased incidence of dementia. However, information supporting seasonal changes in the sleep–wake cycle, the rest–activity rhythm and quality of life in older community-dwelling people remains insufficient. The aim of the present study was to prospectively investigate seasonal effects on the sleep–wake cycle, the rest–activity rhythm and quality of life among older people living in areas of Japan or Thailand with different climate classifications.

Method: The survey was conducted from March 2016 to May 2017, and 109 participants were recruited from Japan and Thailand: 47 older people living in Akita prefecture, Japan, and 62 older people living in Chiang Mai or Nakhon Ratchasima, Thailand. According to the Köppen–Geiger classification of Asian climates comprising tropical, desert, steppe, temperate and subarctic climates, Akita prefecture, which is located in northern Japan, is classified as a humid subarctic climate, while the Thai study areas are classified as tropical savanna. To monitor parameters of the sleep–wake cycle during nighttime (e.g. total sleep time, sleep latency, sleep efficiency, awaking time and frequency of sleep interruptions) and to calculate parameters of the rest–activity rhythm over the 24 h profile (e.g., interdaily stability, intradaily variability, relative amplitude, mean of least active 5 h period and mean of most active 10 h period), all the participants from both countries wore an Actiwatch 2 device on their nondominant wrist continuously for 7 days during each local season. The World Health Organization Quality of Life Questionnaire-BREF (WHOQOL-BREF) was also assessed during each local season.

Results: The final sample size was 37 older people living in Akita prefecture, Japan, and 44 older people living in Thailand; these subjects completed the data collections during each local season. The dropout rates were 21% in Japan and 29% in Thailand. The results for the Japanese subjects showed a significantly shorter sleep time with higher levels of activity during the nighttime on summer (p < 0.001) and a fragmented rest–activity rhythm over the 24 h profile on winter (p < 0.001). The older Thai participants exhibited a poor state of night sleeping year-round, and a significant relationship was observed between seasonal variations in motor activity and the social domain of WHOQOL-BREF for each Thai season (|r| = 0.4, p < 0.01).

Conclusion: These findings provide new and important information regarding seasonal effects on the sleep–wake cycle, the rest–activity rhythm and quality of life in older community-dwelling people living in two different Asian climates. Consequently, clinical preventions targeting such seasonal variations might be useful for improving the quality of life of older Japanese and Thai individuals.     

Epidemiological study on chronotype among preschool children in Japan: Prevalence,sleep–wake patterns,and associated factors

Our current 24-h society and the weekday–weekend switch of our social clocks may affect young children’s sleep and circadian rhythms. However, such evidence is scarce. We conducted a nationwide epidemiological study of sleep and health in preschool children aged 3–5 years attending kindergarten or childcare centers in Japan, using stratified one-stage cluster sampling. The target population was 2 969 627 individuals (as of 1 April 2013). The Children’s ChronoType Questionnaire was used to measure chronotypes (morning (M)-type, neither (N)-type and evening (E)-type), and weekday and weekend sleep–wake parameters. Randomly sampled population estimates were obtained via respondents with a person-level weight, which accounted for survey responses and poststratification. Standard errors and 95% confidence intervals were adjusted for the complex survey design using jackknife estimation. A linear regression model of the correlation between chronotype and sleep–wake parameters and a multivariate logistic regression model for the links between chronotype and putative associated factors were used for statistical analyses. The estimated prevalence of M-, N- and E-types were 31.6%, 55.9% and 10.0%, respectively. The corresponding numbers of children were 937 910, 1 659 574 and 296 083. The remaining 2.5% was not specified. The proportions of children who woke up by themselves during the weekdays were 55.1%, 43.0% and 1.9% for M-, N- and E-types, respectively. Overall, bedtime, sleep onset time, wake-up time and get-up time during the weekdays were 21:04, 21:26, 6:55 and 6:59, respectively. Nocturnal sleep period, time in bed (TIB) and 24 h TIB (TIB and nap) during the weekdays were 9.49, 9.93 and 10.55 h, respectively. Sleep–wake timings were significantly and linearly delayed from M-, N-, to E-types (p < 0.001). The weekday 24 h TIB (10.47–10.66 h) and weekend nocturnal sleep period (9.58–9.76 h) did not differ significantly among chronotypes. For E-types, socially advanced weekdays rising times (approximately 1 h) caused nocturnal sleep deficit (0.57 h). Children’s socially scheduled times (e.g. start and finish times, mealtimes and daytime nap) and their parents’ diurnal preferences had significant adjusted odds ratios among E-types, while the significant unadjusted odds ratios for morning sunlight and multimedia exposure disappeared. These results suggest the importance of chronobiologically planned sleep discipline at home as well as assessment of socially scheduled times in children.     

Living on the edge – The predicted impact of renewed hunting on moose in national parks in Poland

Protected areas are the foundation of biodiversity conservation. However, due to their limited size, unfavourable shape, and isolation they often rarely provide sufficient protection. This problem particularly concerns large mammals, which play the role of key-species and usually have high spatial demands. Since 2001 the moose has been under a hunting ban in Poland after the species experienced a sharp decline due to overharvesting. As there are plans to reopen moose hunting in eastern Poland (excluding national parks and nature reserves), we analysed the potential impact of renewed hunting in areas neighbouring Biebrza and Polesie National Parks (eastern Poland) on moose populations inhabiting these protected areas and investigated the suitability of the existing buffer zones to provide additional protection to moose outside the park boundaries. Analyses were based on the tracking data derived from 33 GPS collared moose (24 – Biebrza NP and 9 – Polesie NP). All of the tracked moose utilized areas both inside and outside national parks. In the Biebrza PN, moose spent 46.9% of their time in areas surrounding the national park, whilst in Polesie NP the proportion was 64.5%. The highest utilization of areas outside both study sites occurred in autumn and winter (October–March), a period that considerably overlaps with the planned hunting season. The southern part of Biebrza NP and its official buffer zone covered 96.2% of all moose fixes, while Polesie NP, its official buffer zone and neighbouring landscape park covered 60.3% of moose records. The buffer zones proposed in this paper, whose widths were calculated on the basis of moose tracking data, would protect from 90.5 (Polesie) to 91.2% (Biebrza) of moose fixes. Proper delineation and adequate management plans in buffer zones would prevent the negative impacts of moose hunting, which has the potential to significantly influence ecotourism in national parks and their vicinity.     

The impact of forest management on litter-dwelling invertebrates: a subtropical–temperate contrast

Land use intensification in forests is a main driver of global biodiversity loss. Although historical state of land use differs between subtropical and temperate zones, gradients of land-use intensities similarly range from unmanaged to very intensively managed forests. Irrespective of similar land use forces in both climate zones, comparative studies on land use effects are still rare. Such studies are, however, promising in discovering more general impacts and geographical specifics of land use intensification. We studied litter-dwelling invertebrates along a gradient of increasing land use intensity in subtropical forests in Southern Brazil and temperate forests in Central Europe using similar sampling designs. Effects of land use intensity on the entire community were analyzed on the level of orders and feeding guilds. In both climate zones a similar number of individuals were caught when standardizes to 100 pitfall trap days, but taxa richness was higher in the subtropics. Moreover, community composition differed between both climate zones. In both regions, land use intensity did not affect taxa richness, but invertebrate abundance was affected in opposite ways; while increasing land use intensity resulted in a decrease of invertebrate abundance in the subtropics, an increase was observed in the temperate zone and this was mostly consistent regarding different feeding guilds. Management practices should take into account that the effect of land use intensity on biodiversity can differ drastically among climatic regions.     

On the influence of prenatal hypoxia on formation of the orexinergic system and sleep–wake cycle in early ontogenesis of rats

The role of orexin in the organization of the sleep–wake cycle (SWC) is well known. The aim of this study was to examine the timing of the orexinergic system formation in rat postnatal ontogenesis and to assess the role of orexin A in the SWC organization under normal conditions and after prenatal hypoxia undergone on days 14 and 19 of embryogenesis. The SWC was investigated in 30-day-old rats with electrodes implanted into the somatosensory and occipital cortex. Immunoreactivity within the orexigenic structures of the lateral hypothalamus was analyzed. It was shown that in control 14-day-old animals the orexinergic structures were in their formative stage, whereas in 30-day-old rats they were already as formed as in adults. In 14-day-old rats, prenatal hypoxia evoked retarded formation of the orexinergic system. In 30-day-old animals, hypoxia undergone in the prenatal period increased the activity of the orexinergic system, which was higher in animals exposed to hypoxia on day 19 than on day 14 of gestation. In 30-day-old rats, these changes were reflected in the SWC formation in the form of shorter slow-wave sleep, more fitful sleep and increased number of transitions from slow- to fast-wave sleep. The results obtained are discussed in the light of the adaptive-compensatory role of the orexigenic system in postnatal ontogenesis after prenatal damage to the central nervous system.     

The effect of hay blowing instead of hay raking on plant biodiversity – a case study of a dry meadow in a Swiss mountain region

Low-input dry meadows are habitats of high nature value. More and more, less time-consuming harvesting techniques replace different steps of the traditional hay making process. The use of leaf blowers instead of rakes for hay making became popular in the last ten years in Switzerland. Thus, we set up a case study to test effects on the conservation value. The studied dry meadow of high nature value is located in the municipality of Stans (Switzerland). After five years no significant differences between blown and raked plots in species richness, richness of target an indicator species, medium plant-indicator values, i.e. nutrients, humidity, light or in the species assemblages were observed. From 2010 until 2014 the moss cover increased in all plots. The differences between raked and blown plots were not significant. In 2015, however, the difference between the two treatments increased to 13%. While the moss cover of the blown plots remained at 20%, the moss cover of the raked plots dropped to 7%. These results from only one case study and only a short observation period of five years do not allow a generalization, but they give a first impression of the short-term effects. We recommend managers of dry meadows with high nature values to keep an eye on the change of moss cover and potential changes of conservation values when leaf blowers instead of rakes are used for hay harvesting.     

Changes in body mass index and smoking habits have a different impact on hemoglobin concentration in men and women: A longitudinal follow-up of the tromsø study, 1994–2002

Background: Body mass index (BMI) and smoking have been positively associated with hemoglobin concentration, and both are risk factors for cardiovascular disease.Objective: The aim of this study was to assess whether there were sex differences in how changes in BMI and smoking habits influenced hemoglobin concentration.Methods: In 1994–95 and 2001–02, a longitudinal, population-based study was conducted in the municipality of Tromsø, in northern Norway. Inhabitants aged ≥25 years were invited to participate. Participants replied to a questionnaire regarding health, physical activity, coffee and alcohol consumption, and smoking habits. Blood samples were drawn to analyze hemoglobin concentration.All analyses were performed separately for each sex. Differences between 1994–95 and 2001–02 were examined with t or χ² (McNemar) tests for paired data. Cross-sectional comparisons were made using 2-sample t tests. Different models of univariate and multiple linear regression analyses were used to investigate the impact of the various variables on hemoglobin change.Results: Data from a total of 2105 men and 2945 women were examined. At baseline, mean age was 58.9 years for men (range, 25–78 years) and 57.8 years for women (range, 25–82 years); mean BMI was 26.1 kg/m² for men and 25.8 kg/m² for women. In men, hemoglobin decreased with age, on average from 147.5 to 145.1 g/L. In women, hemoglobin decreased from 135.6 to 134.7 g/L, but increased with increasing age up to 54 years, and thereafter decreased gradually. Mean BMI increased 0.8 kg/m² in men and 1.2 kg/m² in women. In total, 394 of 2057 men (19%) and 499 of 2889 women (17%) stopped smoking or smoked fewer cigarettes per day. In a univariate regression model, an increase of 1 kg/m² in BMI was associated with an increase in hemoglobin of 1.1 g/L (95% CI, 0.84 to 1.27) in men and 0.4 g/L (95% CI, 0.30 to 0.56) in women. In another univariate model, smoking cessation was associated with a decrease in hemoglobin of 1.9 g/L (95% CI, ?3.32 to ?0.56) in men and 1.7 g/L (95% CI, ?2.93 to ?0.56) in women. In men who smoked less and had a BMI increase of >2.5 kg/m², hemoglobin decreased 0.3 g/L. In contrast, hemoglobin decreased 3.4 g/L in men who smoked less and lost weight (P for trend, < 0.001 by changing BMI). Women who smoked less had a decrease in hemoglobin independent of BMI changes.Conclusions: The positive association between an increase in BMI and hemoglobin was stronger in men than in women. The effect of smoking reduction on hemoglobin was attenuated with increasing BMI in men, but not in women.