Nocturnal Period Research Articles

Feed intake pattern of broiler chickens under intermittent lighting: Do birds eat in the dark?

This paper reflects the results of a short experiment conducted in parallel with a larger trial which aimed to test the assumption that ‘consumption of feed by broiler chickens during periods of darkness is largely negligible’. To that effect, on d 31, feeders of birds raised under intermittent lighting (IL), i.e. 1 h of light [1L]:3 h of dark (3D):1L:3D:1L:3D:1L:3D:2L:6D, were weighed at the onset and at the end of each period of darkness (or scotoperiod). Moreover, in order to compare the feeding behavior of IL birds with that of broilers raised under continuous lighting (CL, i.e. 18L:6D), their feeders were weighed in parallel and at the same time points. On d 31, feed intake of IL birds during scotoperiods represented 45% of their 24 h feed intake. Both CL and IL birds presented anticipatory feed intake prior to the long nocturnal period of darkness (6D), as well as higher feed intake right at the onset of lighting at 06:00. Feed intake of CL birds during the 6D nocturnal scotoperiod was negligible at around 2% of their total feed intake. Intermittent lighting birds exhibited excitement at the start of each hour-length scotoperiod and, within that time, ingested around 2.5 times the amount of feed ingested by CL birds. Although short, this study revealed several interesting observations which might be worth further exploring in a larger, lengthier, behavior-focused experiment. Amongst other factors, it might be interesting to understand whether the high feed intake observed during scotoperiods for IL birds in reflective of the whole flock or rather a coping mechanism developed mainly by hierarchically lower-ranking birds to achieve their daily feed intakes requirements.

Autonomous greenhouse microclimate through hydroponic design and refurbished thermal energy by phase change material

The rapidly increasing demand for agricultural food needs coupled with rising energy costs marked challenges for ensuring food bigger than any previous period. Therefore, greenhouses agriculture is a main focus for farmers, engineers and greenhouses designers in view of ways of improvement that provides. Compared to the conventional greenhouses, hydroponics warrant better quality, greater nutrient content, higher yield, efficient water and fertilizer use, but also more energy requirements. A new Hydroponic Greenhouse was designed and installed in the Research and Technology Center of Energy in Tunisia. A Solar Air Heater with Latent thermal storage using Phase Change Material was also realized for the hydroponic greenhouse heating taking into account the thermal heat loads of the specific application. In this work, the microclimate of the Hydroponic Greenhouse without heating was pursued to evaluate the performance of the hydroponic design. Hydroponic greenhouse allowed better environment than conventional greenhouses. During daytime, the new greenhouse temperature exceeded 18 °C and the difference between the inside and the outside reached mostly 6 °C. The relative humidity ranged between 20 and 35% the day and 70–85% at night.Several measurements were also carried out after the heating to pursue the Solar Air Heater contribution. The temperature of the hydroponic greenhouse during nighttime after the heating raised by 6 °C and the nocturnal temperature was mainly over 15 °C. The diurnal temperature of the Heated Hydroponic Greenhouse was generally higher than 32 °C. Compared to conventional solar heating, the two packed beds of latent storage energy improved the indoor greenhouse environment especially during harsh and nocturnal periods.

Heart rate variability rebound following exposure to persistent and repetitive sleep restriction.

While it is well established that slow-wave sleep electroencephalography (EEG) rebounds following sleep deprivation, very little research has investigated autonomic nervous system recovery. We examined heart rate variability (HRV) and cardiovagal baroreflex sensitivity (BRS) during four blocks of repetitive sleep restriction and sequential nights of recovery sleep. Twenty-one healthy participants completed the 22-day in-hospital protocol. Following three nights of 8-hr sleep, they were assigned to a repetitive sleep restriction condition. Participants had two additional 8-hr recovery sleep periods at the end of the protocol. Sleep EEG, HRV, and BRS were compared for the baseline, the four blocks of sleep restriction, and the second (R2) and third (R3) nocturnal recovery sleep periods following the last sleep restriction block. Within the first hour of each sleep period, vagal activation, as indexed by increase in high frequency (HF; HRV spectrum analysis), showed a rapid increase, reaching its 24-hr peak. HF was more pronounced (rebound) in R2 than during baseline (p < 0.001). The BRS increased within the first hour of sleep and was higher across all sleep restriction blocks and recovery nights (p = 0.039). Rebound rapid eye movement sleep was observed during both R2 and R3 (p = 0.004), whereas slow-wave sleep did not differ between baseline and recovery nights (p > 0.05). Our results indicate that the restoration of autonomic homeostasis requires a time course that includes at least three nights, following an exposure to multiple nights of sleep curtailed to about half the normal nightly amount.

Patterns of Downstream Migration of Pink Salmon Oncorhynchus gorbuscha in the Malaya Khusi River (Sakhalin Oblast)

Patterns of downstream migration of juvenile pink salmon Oncorhynchus gorbuscha in the Malaya Khusi River (northeast of Sakhalin island) are revealed as a result of observations conducted in 2014–2017. Downstream migration starts in May when water is warmed up to 4–5°С. The bulk of fish migrates seaward at 5–10°С. The duration of downstream migration is ~2.5 months. Downstream migration is confined to nocturnal period. Downstream migrants are distributed predominantly in the meadstream, at the line of fastest flow. Some species-specific mechanisms of downstream migration are made clear. The total number of pink salmon downstream migrants during the period of observations is calculated.

Oxidation of benzoic acid from biomass burning in atmospheric waters

This work evaluates the degradation of benzoic acid, a tracer from biomass burning, by different oxidation agents (Fe (III); H2O2; sunlight; and combinations of the previous ones) in model solutions and in real atmospheric waters. The extent of reactions was assessed by Ultraviolet–Visible and molecular fluorescence spectroscopies. The oxidation of benzoic acid occurred with the chemical oxidants Fe (III), H2O2, Fe (III) and H2O2 simultaneously in the presence of sunlight, and with Fe (III) and H2O2 simultaneously in the absence of light. The decrease of the pH value from neutral to acid for atmospheric waters generally increased the extent of oxidation. Sunlight was an important oxidation agent, and its combination with chemical oxidants increased the oxidation rate of benzoic acid, possibly due to the photogeneration of hydroxyl radicals. The results also suggested the occurrence of direct and indirect photolysis of benzoic acid in atmospheric waters. Moreover, the oxidation of benzoic acid produced new and more complex chromophoric compounds, which were then degraded. In addition, the nocturnal period is not sufficient for the full degradation of benzoic acid and of the intermediates formed by Fenton-like oxidation. The diurnal period may be enough for their full degradation through photo-Fenton-like oxidation, but this depends on the composition of the atmospheric waters, namely of the chromophoric content. Thus, this study highlights that benzoic acid from biomass burning, and its derivatives, may persist in atmospheric waters for periods of longer than one day, becoming available for other reactions, and may also affect the terrestrial and aquatic ecosystems through the wet depositions.

Microhabitat selection of axolotls, Ambystoma mexicanum, in artificial and natural aquatic systems

Studies of habitat selection are crucial for the conservation of threatened amphibians. Wild salamanders are often distributed near rocks or vegetation, which provide shelter. However, nothing is known about habitat selection of the Mexican axolotl (Ambystoma mexicanum), an endangered salamander of great cultural and ecological value. This study aims to test the relationship between vegetation presence and the distribution of captive-raised axolotls in two systems: a closed canal in their native ecosystem (n = 10) and an artificial canal within a zoological park (n = 6). We used radio-telemetry to analyse the hourly distribution and movement patterns of axolotls in each study site during 72-h observational periods. We found that movement patterns and microhabitat selection were related to vegetation coverage and diurnal and nocturnal periods. Sex and age had no effect in habitat selection. Axolotls in both study sites preferred vegetated microhabitats, but in Xochimilco this preference was only significant during daytime when they were less active. These habitat-specific patterns of spatial distribution may represent behavioural strategies for reducing predation. The first approach of behavioural insights from this study will inform the construction of refuges to reduce the alarming depletion of axolotls in the wild.

Fasted High-Intensity Interval and Moderate-Intensity Exercise Do Not Lead to Detrimental 24-Hour Blood Glucose Profiles.

To compare the effect of a bout of high-intensity interval training (HIT) with a bout of moderate-intensity continuous training (MICT) on glucose concentrations over the subsequent 24-hour period. Fourteen people with type 1 diabetes [T1D (duration of T1D, 8.2 ± 1.4 years)], all on a basal-bolus regimen, completed a randomized, counterbalanced, crossover study. Continuous glucose monitoring was used to assess glycemic control after a single bout of HIT (six 1-minute intervals) and 30 minutes of MICT on separate days compared with a nonexercise control day (CON). Exercise was undertaken after an overnight fast with omission of short-acting insulin. Capillary blood glucose samples were recorded before and after exercise to assess the acute changes in glycemia during HIT and MICT. There was no difference in the incidence of or percentage of time spent in hypoglycemia, hyperglycemia, or target glucose range over the 24-hour and nocturnal period (12:00 am to 6:00 am) between CON, HIT, and MICT (P > 0.05). Blood glucose concentrations were not significantly (P = 0.49) different from pre-exercise to post-exercise, with HIT (0.39 ± 0.42 mmol/L) or MICT (-0.39 ± 0.66 mmol/L). There was no difference between exercise modes (P = 1.00). HIT or 30 minutes of MICT can be carried out after an overnight fast with no increased risk of hypoglycemia or hyperglycemia. If the pre-exercise glucose concentration is 7 to 14 mmol/L, no additional carbohydrate ingestion is necessary to undertake these exercises. Because HIT is a time-efficient form of exercise, the efficacy and safety of long-term HIT should now be explored.

Abstract 005: Hemodynamic and Renal Changes in Obese Patients 12 Months After Bariatric Surgery

Aim: to study changes in central and peripheral 24h-BP, as well as in estimated glomerular filtration rate (eGFR) and albuminuria (Alb), 12 months after bariatric surgery (BS). Methods: Sixty-two patients (39% hypertensives) with severe obesity (BMI 42.7±5.6 Kg/m 2 ) were evaluated prospectively before (0) and 1,3,6 and 12 months after undergoing BS. Peripheral and central BP parameters were determined by the Mobil-O-Graph device. Renal function was evaluated by eGFR and Alb. Generalized estimation equations were used to evaluate repeated measures in the variables analyzed. Results: at 12 months weight (-35.7±9.9 Kg) and waist circumference (-27 ± 9.2 cm) decreased (p&lt;0.001 for both). The Table shows a significant decrease in only systolic BP, in both the 24h and daytime periods, but not in the nocturnal period. There was a decrease in plasma aldosterone (Ald) levels (mean,95%CI: -36.7 pg/mL, -60 to -13.4, p=0.003). After adjusting for age, BP 0 , variation (Δ) of weight, Δ Ald and having or not HT at baseline, the only significant covariables in Δ 24h-SBP and Δ day-SBP were previous HT and Δweight. There was a decrease in eGFR (mean,95%CI: -5.6 mL/min/1.73m 2 , -9.4 to -1.8, p=0.005) and Alb (Z=-2.04,p=0.042). According to the constructed variance analysis models, the Δ Alb was dependent on Alb 0 and on Δ night-SBP, but not on the baseline hypertensive state, on the Δ eGFR nor on the Δweight (adjusted r 2 =0.606). Δ eGFR was independent of baseline eGFR and Δ weight. Conclusions: patients with morbid obesity significantly reduce heart rate and 24h- and day- SBP, both central and peripheral, 12 months after undergoing BS. In addition, there is a significant decrease in plasma Ald, eGFR and Alb.

Precision feeding strategy for growing pigs under heat stress conditions.

This study evaluated the responses of individual daily precision (IPF) and conventional 2-phase (CON) feeding systems (FS) in terms of pig growth performance, nutrient balance, serum parameters, and meal patterns of growing pigs reared under thermoneutral (TN: 23 °C) and heat stress (high temperature [HT]: 30 °C) conditions. The animals in each treatment were assigned on the basis of equal BW to the experimental treatments (12 animals per treatment at 41.0 ± 4.87 kg of BW). The experiment lasted 55 d (phase 1 from days 0 to 27 and phase 2 from days 28 to 55). Pigs fed CON received within each phase a constant blend of diets with high and low nutrient density supplying the estimated nutrient requirements of the group, whereas the IPF pigs received daily a personalized blend providing the estimated amount of nutrients according to individual feed intake and body weight information. Body mineral content, and lean and fat masses were assessed through dual-energy X-ray absorptiometry at the beginning and end of each phase. Data were analyzed using a linear mixed-effect model, with fixed effects of the FS, temperature (AT), and the 2-way interaction between FS and AT and random effects of blocks. In relation to CON pigs, IPF pigs reduced (P < 0.05) Lys (19%), protein (16%), and P (14%) intake without impairing (P > 0.05) body composition. Nitrogen excretion was 24% lower (P < 0.05) in IPF pigs than in CON pigs; however, both groups had similar N retention efficiency thoroughly the trial. Amount of time feeding, feed intake rate, and feed intake per meal were 15% lower (P < 0.05) in pigs raised under HT than under TN conditions. During the phase 2, only amount of time feeding, feed intake rate, and feed intake per meal were decreased (P < 0.05) in pigs under HT conditions during nocturnal (2000 to 0500 h) and diurnal (0501 to 1959 h) periods. Haptoglobin levels were affected by the AT, showing an increase of 70% and 43% in HT at 28 and 55 d of the experiment, respectively. Pigs raised under HT conditions had 10% lower (P < 0.05) serum albumin concentration at day 55 than those under TN conditions. For serum urea concentrations, IPF pigs had 28% lower (P < 0.01) levels than CON pigs. Even though HT conditions considerably reduced growth performance and activated inflammatory responses in growing pigs, IPF was not able to rescue performance during HT; however, it was equally effective at improving nutrient utilization and maintaining body composition in HT and TN conditions.

Overnight memory consolidation facilitates rather than interferes with new learning of similar materials-a study probing NMDA receptors.

Although sleep-dependent consolidation and its neurochemical underpinnings have been strongly researched, less is known about how consolidation during sleep affects subsequent learning. Since sleep enhances memory, it can be expected to pro-actively interfere with learning after sleep, in particular of similar materials. This pro-active interference should be enhanced by substances that benefit consolidation during sleep, such as D-cycloserine. We tested this hypothesis in two groups (Sleep, Wake) of young healthy participants receiving on one occasion D-cycloserine (175 mg) and on another occasion placebo, according to a double-blind balanced crossover design. Treatment was administered after participants had learned a set of word pairs (A-B list) and before nocturnal retention periods of sleep vs. wakefulness. After D-cycloserine blood plasma levels had dropped to negligible amounts, i.e., the next day in the evening, participants learned, in three sequential runs, new sets of word pairs. One list-to enhance interference-consisted of the same cue words as the original set paired with a new target word (A-C list) and the other of completely new cue words (D-E set). Unexpectedly, during post-retention learning the A-C interference list was generally better learned than the completely new D-E list, which suggests that consolidation of previously encoded similar material enhances memory integration rather than pro-active interference. Consistent with this view, new learning of word pairs was better after sleep than wakefulness. Similarly, D-cycloserine generally enhanced learning of new word pairs, compared to placebo. This effect being independent of sleep or wakefulness, leads us to speculate that D-cycloserine, in addition to enhancing sleep-dependent consolidation, might mediate a time-dependent process of active forgetting.

Glucose Variables in T1D Studies with Dapagliflozin—Pooled Analysis of Continuous Glucose Monitoring Data from DEPICT-1 and 2

Improved glycemic control and weight loss, without increased hypoglycemia, were demonstrated in two short-term, 24-week, Phase 3 studies of the SGLT2 inhibitor dapagliflozin (DAPA) as adjunct to adjustable insulin in patients with inadequately controlled T1D (DEPICT-1 and 2). In this post-hoc analysis we pooled continuous glucose monitoring (CGM) data at baseline and week 24 from both studies. In total, 1591 patients were included (DAPA 5 mg N=530; DAPA 10 mg N=529; placebo N=532). Baseline characteristics were comparable between the study groups. DAPA treatment significantly reduced mean interstitial glucose, mean amplitude of glucose excursions (MAGE), and postprandial glucose, while expanding the time in glycemic target range (&amp;gt;70 mg/dL to ≤180 mg/dL)(Table). In addition, DAPA treatment did not increase the percent of glucose readings ≤70 mg/dL or ≤54 mg/dL, or the percent of readings ≤70 mg/dL in the nocturnal period (00:00 to 05:59). These results demonstrate that DAPA as adjunct to insulin in patients with T1D reduced glycemic variability without increasing time in the hypoglycemia range.Table. Pooled CGM parametersCGM parameterTreatment armMean baseline value (SD)Mean Week 24 value (SD)Adjusted mean change from baseline (SE)Difference vs. placebo (95% CI)Mean 24-hour glucose readings (mg/dL)DAPA 5 mg193.00 (28.78)179.93 (32.41)-8.40 (1.30)−15.48 (−18.82, −12.13)DAPA 10 mg191.00 (28.11)174.87 (26.59)–11.82 (1.32)−18.90 (−22.25, − 15.54)Placebo191.64 (29.04)194.34 (32.62)7.07 (1.33)MAGE (mg/dL)DAPA 5 mg170.53 (30.55)154.67 (34.21)–12.48 (1.37)−13.36 (−16.89, −9.83)DAPA 10 mg171.01 (31.59)154.52 (34.52)–13.06 (1.39)−13.94 (−17.48, −10.40)Placebo168.99 (31.46)166.94 (31.62)0.88 (1.40)Percent of 24-hour glucose values within &amp;gt;70 – ≤180 mg/dL (%)DAPA 5 mg43.38 (12.22)51.69 (14.49)6.48 (0.60)9.07 (7.55, 10.59)DAPA 10 mg43.98 (12.32)53.89 (13.26)8.08 (0.60)10.67 (9.15, 12.20)Placebo43.66 (12.64)43.10 (13.97)–2.59 (0.61)Percent of glucose readings ≤70 mg/dL over 24-hours (%)DAPA 5 mg4.96 (4.64)4.85 (4.89)–0.43 (0.21)0.06 (–0.47, 0.59)DAPA 10 mg5.30 (4.90)5.10 (4.44)–0.33 (0.21)0.16 (–0.38, 0.69)Placebo5.14 (5.56)4.83 (4.72)–0.49 (0.21)Percent of glucose readings ≤54 mg/dL (%)DAPA 5 mg2.22 (2.87)2.02 (2.83)–0.32 (0.13)–0.14 (–0.47, 0.19)DAPA 10 mg2.34 (3.13)2.05 (2.63)–0.34 (0.13)–0.16 (–0.48, 0.17)Placebo2.28 (3.82)2.15 (3.15)–0.19 (0.13)Postprandial glucose readings by CGM (mg/dL)DAPA 5 mg199.42 (40.51)192.97 (43.90)–0.85 (1.99)–8.55 (–13.70, –3.41)DAPA 10 mg196.61 (38.57)186.93 (36.21)–5.05 (2.02)–12.76 (–17.93, –7.58)Placebo197.35 (42.32)199.68 (44.36)7.70 (2.03)Percent of nocturnal (00:00–05:59) glucose values ≤70 mg/dL (%)DAPA 5 mg5.94 (7.64)5.95 (8.26)–0.38 (0.36)–0.15 (–1.07, 0.78)DAPA 10 mg5.52 (7.22)6.00 (7.60)–0.18 (0.37)0.06 (–0.87, 0.99)Placebo5.83 (7.74)5.85 (7.64)–0.24 (0.37) Disclosure C. Mathieu: Research Support; Self; Novo Nordisk A/S. Advisory Panel; Self; Novo Nordisk A/S. Speaker's Bureau; Self; Novo Nordisk A/S. Research Support; Self; Sanofi. Speaker's Bureau; Self; Sanofi. Advisory Panel; Self; Sanofi. Research Support; Self; Merck Sharp &amp; Dohme Corp.. Speaker's Bureau; Self; Merck Sharp &amp; Dohme Corp.. Advisory Panel; Self; Merck Sharp &amp; Dohme Corp.. Research Support; Self; Eli Lilly and Company. Speaker's Bureau; Self; Eli Lilly and Company. Advisory Panel; Self; Eli Lilly and Company. Research Support; Self; Novartis AG. Speaker's Bureau; Self; Novartis AG. Advisory Panel; Self; Novartis AG, Bristol-Myers Squibb Company. Speaker's Bureau; Self; AstraZeneca. Advisory Panel; Self; AstraZeneca, Pfizer Inc., Janssen Pharmaceuticals, Inc., Boehringer Ingelheim GmbH. Speaker's Bureau; Self; Boehringer Ingelheim GmbH. Advisory Panel; Self; Hanmi Pharmaceutical. Research Support; Self; Roche Diagnostics Corporation. Advisory Panel; Self; Roche Diagnostics Corporation. Research Support; Self; Medtronic. Advisory Panel; Self; Medtronic, MannKind Corporation. Research Support; Self; Intrexon. Advisory Panel; Self; Intrexon, Dianax, UCB, Inc.. Research Support; Self; Abbott. P. Dandona: Advisory Panel; Self; AstraZeneca. Consultant; Self; AstraZeneca. Research Support; Self; AstraZeneca. M. Phillip: Other Relationship; Self; Sanofi, Medtronic MiniMed, Inc., Novo Nordisk A/S. Speaker's Bureau; Self; Eli Lilly and Company. Research Support; Self; Merck &amp; Co., Inc., Bristol-Myers Squibb Company, Kamada, Lexicon Pharmaceuticals, Inc.. Other Relationship; Self; DreaMed Diabetes, Ltd.. Speaker's Bureau; Self; Abbott. T. Oron: None. L. Hansen: Employee; Self; MedImmune. F.A. Thoren: Employee; Self; AstraZeneca. J. Xu: Employee; Self; AstraZeneca. A. Langkilde: Employee; Self; AstraZeneca. Stock/Shareholder; Self; AstraZeneca.

A Case Study of Turbulence in the Nocturnal Boundary Layer During the Indian Summer Monsoon

Observations from the Cloud-Aerosol Interaction and Precipitation Enhancement Experiment-Integrated Ground Observation Campaign (CAIPEEX-IGOC) provide a rare opportunity to investigate nocturnal atmospheric surface-layer processes and surface-layer turbulent characteristics associated with the low-level jet (LLJ). Here, an observational case study of the nocturnal boundary layer is presented during the peak monsoon season over Peninsular India using data collected over a single night representative of the synoptic conditions of the Indian summer monsoon. Datasets based on Doppler lidar and eddy-covariance are used for this purpose. The LLJ is found to generate nocturnal turbulence by introducing mechanical shear at higher levels within the boundary layer. Sporadic and intermittent turbulent events observed during this period are closely associated with large eddies at the scale of the height of the jet nose. Flux densities in the stable boundary layer are observed to become non-local under the influence of the LLJ. Different turbulence regimes are identified, along with transitions between turbulent periods and intermittency. Wavelet analysis is used to elucidate the presence of large-scale eddies and associated intermittency during nocturnal periods in the surface layer. Although the LLJ is a regional-scale phenomenon it has far reaching consequences with regard to surface-atmosphere exchange processes.

Validation of the Sleep-Wake Scoring of a New Wrist-Worn Sleep Monitoring Device.

To test the sleep-wake scoring reliability of a new wrist-worn sleep monitoring device. Twenty-seven adult good sleepers underwent 1 night of polysomnography (PSG) while wearing both the new device (myCadian [MC]; CurAegis Technologies, Rochester, New York, United States) and commercially available actigraphy (Actiwatch 2 [AW]; Philips Respironics, Murrysville, Pennsylvania, United States) on their nondominant wrist. PSG tests were manually stage scored. After excluding missing data, 20 participants had full-night data on all three devices with 17,734 total 30-second epochs. Using PSG as the gold standard, pooled epoch-by-epoch agreement for sleep and wake was calculated for each device using percent agreement and Cohen kappa statistic. Positive predictive values for both sleep and wake epochs, as well as sleep continuity statistics, were calculated. Percent agreement with PSG-scored wake and sleep was 91.3% for MC (kappa = 0.67) and 87.7% for AW (kappa = 0.50). Positive predictive values for sleep epochs were 94.4% and 90.8% for MC and AW, respectively, and 74.5% and 65.6% for wake. Both devices underestimated wake and overestimated sleep compared to PSG. Descriptively, compared to PSG, sleep latency was higher with MC and wake after sleep onset higher with AW. Total sleep time and sleep efficiency were more similar across devices. The kappa statistic for MC is consistent with a high level of agreement with PSG. Overall, the reliability of MC compared to PSG scoring was slightly more favorable than that of AW. Findings suggest that MC provides reliable sleep-wake scoring during a nocturnal sleep period for good sleepers.

Creeping in the night: What might ecologists be missing?

Wildlife activity patterns tend to be defined by terms such as diurnal and nocturnal that might not fully depict the complexity of a species’ life history strategy and behavior in a given system. These activity pattern categories often influence the methodological approaches employed, including the temporal period of study (daylight or nighttime). We evaluated banded mongoose (Mungos mungo) behavior in Northern Botswana through the use of remote sensing cameras at active den sites in order to characterize early morning behavior for this diurnal species. Our approach, however, provided the facility to capture unexpected nocturnal activity in a species that had otherwise only been studied during daylight hours. Camera traps were deployed for 215 trap days (24 hour data capture period) at den sites, capturing 5,472 photos over all events. Nocturnal activity was identified in 3% of trap days at study den sites with both vigilant and non-vigilant nocturnal behaviors identified. While vigilant behaviors involved troop fleeing responses, observations of non-vigilant behaviors suggest nonresident mongoose may investigate den sites of other troops during nocturnal time periods. There was no association between the occurrence of nocturnal activity and lunar phase (Fisher’s exact test, n = 215, p = 0.638) and thus, increased moonlight was not identified as a factor influencing nocturnal behavior. The drivers and fitness consequences of these nocturnal activities remain uncertain and present intriguing areas for future research. Our findings highlight the need for ecological studies to more explicitly address and evaluate the potential for temporal variability in activity periods. Modifying our approach and embracing variation in wildlife activity patterns might provide new insights into the interaction between ecological phenomenon and species biology that spans the diurnal–nocturnal spectrum.

Abiotic drivers of activity in a large, free-ranging, freshwater teleost, Murray cod (Maccullochella peelii).

The allocation of time and energy to different behaviours can impact survival and fitness, and ultimately influence population dynamics. Intrinsically, the rate at which animals expend energy is a key component in understanding how they interact with surrounding environments. Activity, derived through locomotion and basic metabolism, represents the principal energy cost for most animals, although it is rarely quantified in the field. We examined some abiotic drivers of variability in locomotor activity of a free-ranging freshwater predatory fish, Murray cod (Maccullochella peelii), for six months using tri-axial accelerometers. Murray cod (n = 20) occupied discrete river reaches and generally exhibited small-scale movements (<5 km). Activity was highest during crepuscular and nocturnal periods when water temperatures were warmest (19–30°C; January–March). As water temperatures cooled (9–21°C; April–June) Murray cod were active throughout the full diel cycle and dormant periods were rarely observed. Light level, water temperature and river discharge all had a significant, non-linear effect on activity. Activity peaked during low light levels, at water temperatures of ~20°C, and at discharge rates of ~400 ML d-1. The temporal changes observed in the behaviour of Murray cod likely reflect the complex interactions between physiological requirements and prey resource behaviour and availability in driving activity, and highlight the importance of empirical field data to inform bioenergetics models.

Hygienic Behavior of Honeybee (Apis mellifera L.) and Efficiency of Volatile Oils against Varroa destructor

The study was carried out at the apiary of Department of Plant Protection Faculty of Agriculture Al-Azhar University, Cairo, Egypt, to determine the effects of diurnal and nocturnal periods on hygienic behavior of Carniolan F1 and Italian F1 hybrids colonies under Nasr City environmental conditions, and to evaluate the using of plant oils against Varroa destructor mite. Hygienic behavior in honeybee Apis mellifera, is measured by determining the rate ofthe bees uncap and remove dead sealed brood. Significant differences between hygienic behavior during diurnal and nocturnal activities, as well as between hybrids were found. The average of hygienic percentages at diurnal of Italian F1 hybrid colonies were 63.33, 82.67, and 85.33 % and for Carniolan F1 hybrid colonies were 45.33, 59.67, and 77.33 % after 12, 18 and 24 hrs, respectively. The average of hygienic percentages at nocturnal of Italian F1 hybrid colonies were 93.00, 98.00, and 100.00 % and for Carniolan F1 hybrid colonies were 67.00, 83.67, and 95.00 % after 12, 18 and 24 hrs, respectively. The highest mean numbers of fallen mites/colony (39.67 mites) were obtained from colonies treated with olive oil, followed by 35.00 mites from colonies treated with Mitac, then 27.00 mites from colonies treated with mustard oil. It could be advisable to use plant oils to control Varroa mite infesting honeybee colonies to avoid the appearance of mite resistant strains and products pollution.

Numerical simulations for the sources apportionment and control strategies of PM2.5 over Pearl River Delta, China, part II: Vertical distribution and emission reduction strategies

The contribution of various emission sources to the vertical structure of the PM2.5 concentration and the modeling of emission reduction strategies are emphasized in this study. Analysis of vertical distribution of PM2.5 concentration in the planetary boundary layer (PBL) reveals that strong diurnal cycle exists during the pollution episodes, with heavier surface pollution in nocturnal periods. Contributions from transportation and agriculture are mainly restricted to the surface, while contributions from industry and power are distributed in a relatively higher layer. In the northerly-controlled episodes, the contribution of local emissions mainly accumulates below 300 m and the impact of the emissions from surrounding cities can reach 500–600 m during nocturnal periods. The contributions outside of Guangdong are uniformly distributed within 1000 m altitude. In the daytime, the contribution of emissions is basically uniform throughout the PBL. In the southerly-controlled episodes, the contribution of local emission mainly concentrates below 400 m during the nocturnal periods. Emissions from surrounding cities can exert the influence below 1000 m height, and the contribution outside of Guangdong reaches even 1500 m. In the daytime, the contribution of emissions in the PBL is distributed evenly. The highest altitude of the contribution from different subdomains that can reach is closely related to the physical property of the PBL. The industrial and agricultural emissions are the most important contributors for the surface PM2.5 concentration. Results from emission reduction experiments show that PM2.5 reduces significantly near the pollution center. Although control efficiency decreases with the increasing reduction ratio, the efficiency differences between 30% and 50% reduction is limited. In particular, 10% reduction in industrial emission causes PM2.5 concentration to be slightly higher in the afternoon. Furthermore, below 200-m height, emission reduction experiments perform the effective reduction in PM2.5 concentration, and higher reduction ratio results in larger reduced PM2.5 concentration on almost all layers in the PBL.

Estimation of nocturnal CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and N&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;O soil emissions from changes in surface boundary layer mass storage

Abstract. Annual budgets of greenhouse and other trace gases require knowledge of the emissions throughout the year. Unfortunately, emissions into the surface boundary layer during stable, calm nocturnal periods are not measurable using most micrometeorological methods due to non-stationarity and uncoupled flow. However, during nocturnal periods with very light winds, carbon dioxide (CO2) and nitrous oxide (N2O) frequently accumulate near the surface and this mass accumulation can be used to determine emissions. Gas concentrations were measured at four heights (one within and three above canopy) and turbulence was measured at three heights above a mature 2.5 m maize canopy from 23 July to 10 September 2015. Nocturnal CO2 and N2O fluxes from the canopy were determined using the accumulation of mass within a 6.3 m control volume and out the top of the control volume within the nocturnal surface boundary layer. Diffusive fluxes were estimated by flux gradient method. The total accumulative and diffusive fluxes during near-calm nights (friction velocities &lt; 0.05 ms−1) averaged 1.16 µmol m−2 s−1 CO2 and 0.53 nmol m−2 s−1 N2O. Fluxes were also measured using chambers. Daily mean CO2 fluxes determined by the accumulation method were 90 to 130 % of those determined using soil chambers. Daily mean N2O fluxes determined by the accumulation method were 60 to 80 % of that determined using soil chambers. The better signal-to-noise ratios of the chamber method for CO2 over N2O, non-stationary flow, assumed Schmidt numbers, and anemometer tilt were likely contributing reasons for the differences in chambers versus accumulated nocturnal mass flux estimates. Near-surface N2O accumulative flux measurements in more homogeneous regions and with greater depth are needed to confirm the conclusion that mass accumulation can be effectively used to estimate soil emissions during nearly calm nights.

Adaptive genomic evolution of opsins reveals that early mammals flourished in nocturnal environments

BackgroundBased on evolutionary patterns of the vertebrate eye, Walls (1942) hypothesized that early placental mammals evolved primarily in nocturnal habitats. However, not only Eutheria, but all mammals show photic characteristics (i.e. dichromatic vision, rod-dominated retina) suggestive of a scotopic eye design.ResultsHere, we used integrative comparative genomic and phylogenetic methodologies employing the photoreceptive opsin gene family in 154 mammals to test the likelihood of a nocturnal period in the emergence of all mammals. We showed that mammals possess genomic patterns concordant with a nocturnal ancestry. The loss of the RH2, VA, PARA, PARIE and OPN4x opsins in all mammals led us to advance a probable and most-parsimonious hypothesis of a global nocturnal bottleneck that explains the loss of these genes in the emerging lineage (> > 215.5 million years ago). In addition, ancestral character reconstruction analyses provided strong evidence that ancestral mammals possessed a nocturnal lifestyle, ultra-violet-sensitive vision, low visual acuity and low orbit convergence (i.e. panoramic vision).ConclusionsOverall, this study provides insight into the evolutionary history of the mammalian eye while discussing important ecological aspects of the photic paleo-environments ancestral mammals have occupied.

Desmopressin and nocturnal voiding dysfunction: Clinical evidence and safety profile in the treatment of nocturia

ABSTRACTIntroduction: Nocturia is a common urinary condition experienced by both men and women. While desmopressin has historically been utilized to treat conditions such as central diabetes insipidus and primary nocturnal enuresis, there is an increased interest in the use of desmopressin in the management of adult nocturia.Areas covered: This article provides a review on the pathophysiology of nocturia and the clinical outcomes and safety profile of desmopressin in the management of adult nocturnal voiding dysfunction.Expert opinion: To date, desmopressin is the only anti-diuretic hormone that is approved for nocturia. Published literature on desmopressin demonstrate good clinical efficacy in terms of number of nocturnal voids, voided volume and sleep period. Newer formulations have shown that a minimum dosage of 25 μg orally disintegrating sublingual desmopressin appears to be ideal for women, whereas men usually benefit from a minimum of 50 μg. Of the known adverse drug reactions, hyponatremia remains a major concern especially in patients over 65 years of age. At present, long term data on desmopressin remains scarce. Lastly, it is important to stress that no single treatment deals with nocturia in all contexts, and careful assessment remains essential to identify the appropriate and safest treatment in each patient.