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The design of Ripple-2, a wireless in-situ soil moisture sensing system is presented in this paper. The main objective of such system is to collect high fidelity and fine grained data both spatially and temporally compared to radar remote sensing, which is the more traditional way of capturing soil moisture, and to use the former to validate and calibrate the latter. To do so, the in-site sensor network must cover a sufficiently large area, on the order of at least a few square kilometers. At the same time, cost constraints (both in deployment and in maintenance) puts a limit on the total number of sensor nodes, resulting in a very sparse (on average) network. The main challenge in designing the system lies in achieving reliability and energy efficiency in such a sparse network. For instance, in our pilot deployment, a 200mx400m area is covered by 22 nodes (average inter-node distance > 50m). Traditional WSN technology typically calls for many more nodes to be deployed in such an area. Ripple-2 is introduced as a non-traditional WSN architecture where (1) the network is physically and logically segmented into isolated clusters, (2) a regular node (or end device, ED) only communicates with the cluster head (CH) of its segment, and (3) the ED-CH communication is distinct from the CH-sink (or CH-Data Server) and both links can use virtually any kind of point-to-point wireless technology. We use both simulated and empirical results to demonstrate the effectiveness of Ripple-2; it proves to be ideal for low duty-cycle data collection applications due to its exceptional small network overhead (typically smaller than 1%) and its robustness to the size of the network [ABSTRACT FROM AUTHOR]

The Sleep and the hibernation are provided as power saving mode on computers. This paper discusses the advantage of the hibernation, proposes a method to accelerate the resume transition by more than a few times, and shows the test results on Windows system. This method is implemented in “ThinkPad” that is a brand of laptop computers developed by Lenovo. [ABSTRACT FROM PUBLISHER]

The number of mobile devices such as smart phones, tablet PCs, e-book readers and laptop computers is increasing. It is important for longer battery life and green energy to reduce power consumption when those devices are in running state. What is also important is to reduce standby power, because those devices stay in standby state for a longer period of time than in running state and the power consumption in standby state is far from negligible. This paper discusses the software algorithm on laptop computers which learns how and when a laptop computer is placed into standby state and is resumed by a user, predicts when a user will resume the computer, and automatically changes the depth of the standby state to reduce the power consumption without resume performance degradation. This method is implemented in “TinkPad” that is a brand of laptop computers developed by Lenovo. [ABSTRACT FROM PUBLISHER]

Memetic algorithms combine evolutionary algorithms with local search heuristics in order to speed up the evolutionary process. the bacterial memetic algorithm applies the bacterial operators instead of the genetic algorithm's crossover and mutation operator. in this paper a novel diversity induction method is proposed for bacterial memetic algorithm. Hibernation of some individuals in the population is applied for avoiding premature convergence to local optima. This operation can help in turning back from unpromising region of the search space by previously found solutions represented in hibernated bacteria. [ABSTRACT FROM PUBLISHER]

Clusters of computing servers have become integral components to support various online services and other large computational workloads. With the growing use of cluster systems in web servers, file distribution and database transactions, power conservation and efficiency have been identified as critical issues in the design of server cluster systems. The server cluster electricity costs are of the order of millions annually for larger clusters, and add up to a significant part of the electrical power consumption in all. To reduce power consumption, a master in a server cluster should hibernate the idle servers following the pattern observed from the historical data. This technique saves energy that would have been consumed by the idle servers if not hibernated. We focus on finding patterns from historical data and arriving at decision logic to send a server to hibernation. [ABSTRACT FROM AUTHOR]

The current "epidemic" of methamphetamine is not the first since the drug's discovery in 1893 by a Japanese pharmacologist. This paper identifies patterns common across four perceived methamphetamine epidemics. The discussion includes social conditions predating epidemics, dormancy of the problem, surge and alarm, morphing of the problem, hibernation, amnesia, and incubation. The paper concludes with implications for: legal production of the drug, physicians and pharmacists, enforcement strategies, prevention efforts, treatment, and management of the epidemic and its aftermath. ..PAT.-Unpublished Manuscript [ABSTRACT FROM AUTHOR]

Hibernating mammals survive winter season by periodically lowering their body temperature down to the freezing point. The hibernation regulation therefore means a great challenge to their cardiovascular systems. To elucidate the underlying adaptation, we compared the excitation-contraction (E-C) coupling in ventricular cardiomyocytes from hibernating (HGS) and awake (AGS) ground squirrels. Whole-cell voltage clamp showed that the current through L-type Ca2+ channels (LCC) was down-regulated in HGS compared with that in AGS. However, simultaneous recording of fluo-4 fluorescence revealed that the Ca2+ transient triggered by LCC current was not decreased. The gain of Ca2+-induce Ca2+ release (CICR) was thus enhanced remarkably in hibernation. To seek the molecular mechanisms, we investigated the intermolecular signaling between a single LCC and ryanodine receptors (RyRs). Loose-patch confocal imaging showed that the LCC-RyR coupling exhibited shortened latency and increased chance-of-hit in HGS. The enhancement of LCC-RyR signaling efficiency was not attributable to any difference in the Ca2+ contents in the sarcoplasmic reticulum (SR). Realtime PCR and western blot both revealed that the expression of junctophilin-2, a protein anchoring the RyR-residing SR to the LCC-residing T-tubules, was up-regulated in HGS. These data indicated hibernation comes with a regulation that enhances the efficiency of E-C coupling in heart cells. This molecular and functional remodeling is exactly opposite to that occurring in failing hearts, and thus provides an ideal research model for seeking new strategies against heart failure. [ABSTRACT FROM AUTHOR]

Hibernation is a fully reversible condition characterized by hypometabolism and deep hypothermia. Core body temperature (Tb) in hibernating ground squirrels decreases to within 1 or 2°C of ambient temperature (Ta) and can fall to as low as -3°C (Barnes, 1989). In recent work, we showed that the arctic ground squirrel enters hibernation through activation of CNS adenosine A1 receptors (A1AR) (Jinka et al., 2011), in a manner consistent with the inhibition of thermogenesis. Similarly, A1AR agonists in nonhibernating species mediate a hypothermic response through effects on the CNS (Anderson et al., 1994). Several aspects of the hibernation phenotype have therapeutic implications (Drew et al., 2001). Here we harness mechanisms hibernating animals use to cool during onset of torpor for therapeutic hypothermia (TH). TH is the only treatment known to improve prognosis for cardiac arrest patients (Hypothermia-after-Cardiac-Arrest-Study-Group, 2002). Thermoregulatory responses such as shivering, however, complicate cooling in comatose cardiac arrest patients and limit efficacy of TH in conscious stroke patients (Zgavc et al., 2011). Stimulating CNS A1AR to suppress thermogenesis mimics the process hibernating animals use to cool during onset of hibernation. Here we describe a strategy of targeted temperature management based on principles of CNS control of hibernation. All work on animals was approved by the UAF IACUC. In these experiments the A1AR agonist 6N-cyclohexyladenosine (CHA) was administered to rats (male, 69-75 days old; 250- 350g, n=6) at a Ta of 16°C to lower body temperature. 8-(p- Sulfophenyl)theophylline (8-SPT), a nonselective adenosine receptor antagonist that does not cross the blood brain barrier was administered prior to CHA to mitigate direct effects of CHA on the heart. Asphyxial cardiac arrest was performed as before (Dave et al., 2006). Rats were anesthetized with 4% isoflurane and a 30:70 mixture of O2 and N2O followed by endotracheal intubation and mechanical ventilation. Vecuronium (1mg/kg) was injected iv and apnea induced by disconnecting the ventilator from the endotracheal tube to induce cardiac arrest. Adequacy of isoflurane anesthesia was assessed prior to onset of neuromuscular blockade and maintained at this level for less than 10 min before cardiac arrest induced a comatose state. Resuscitation was initiated after 8 min of apnea. Rats resuscitated within 120 sec were screened for additional inclusion criteria and randomly allocated to TH or normothermic control (NC) treatment groups. Subcutaneous body temperature was monitored using IPTT-300 transponders (Biomedic Data Systems, Inc., USA). Treatments: The TH group was administered 8-SPT (25mg/kg,ip) 15min prior to CHA 1mg/kg,ip. This drug combination was administered 6 times at 4h intervals to rats held at a Ta of 16°C. The NC group was administered 8-SPT vehicle (saline) 15 min prior to CHA vehicle (0.1M phosphate buffer) in the same manner as 8-SPT/CHA and held in a neonatal incubator set to 29°C. Treatment commenced 70min after restoration of spontaneous circulation (ROSC) and continued for 24h. The final injection of CHA was administered at 20h and rats rewarmed at 24h by returning to the home room at a Ta of 20°C. Histology: 7 days after ROSC rats were perfused as before (Dave et al., 2006) and hippocampal CA1 regions examined for histopathology. Results: Mean ± SEM Tb was 33.5°C±0.07 and 33.5°C±0.14 in the NC and TH groups at onset of treatment. Tb in all 3 NC rats increased to 36.5-36.8 within 15 min of placement at 29°C and remained between 36.2 and 37.3°C until death. Only 1 rat in the NC group survived to 7 days. The remaining 2 rats died between 13-18h after ROSC. Tb in the 3 rats treated with TH decreased to 31.0 to 31.6°C within 3h of CHA injection and remained between 31.8 and 29.2°C for 24h before rewarming. Rats rewarmed within 5h after transfer to a Ta of 20°C, 4h after the last injection of CHA. Qualitative assessment of CA1 histopathology in TH treated rats indicated an absence of pathology; the CA1 in TH treated rats appeared similar to CA1 in naïve rats. Quantitative analysis by an observer unaware of treatment indicated that the number of healthy neurons in CA1 of TH treated rats was not statistically different from naïve rats, p=0.154, n=3-5. Conclusion: Activation of CNS A1AR in animals exposed to a thermal gradient (Ta of 16°C) is a simple and effective means of inducing TH. Animals cooled in this manner survived cardiac arrest better than control treated animals and showed no evidence of histopathology in CA1 when compared to naïve rats. These results suggest that by mimicking mechanisms used by hibernating animals to cool it will be possible to administer therapeutic hypothermia in a highly effective, noninvasive and reversible manner. [ABSTRACT FROM AUTHOR]

Hibernating ground squirrels survive physiological deviations so removed from the mammalian norm that they inevitably lead to death in non-hibernators. In 13-lined ground squirrels and other circannual, or obligate, hibernators, a season of homeothermy that begins with reproduction and ends with obesity is segregated from a season of hibernation. Hibernation is characterized by cycles between extended (~2 weeks) bouts of torpor, punctuated by short (12 hr) arousals to typical euthermic conditions that are superimposed upon months of continuous fasting and inactivity. In torpor, the hibernating mammal exhibits profound drops in heart rate from a few hundred to a few beats/min, metabolic rate to a few percent of active, and core body temperature from 37°C to near zero. Remarkably, the physiological depressions are spontaneously reversed without harm during each arousal. Moreover, at the end of hibernation, the animal returns to homeothermy with surprisingly little muscle, gut or bone disuse atrophy. Clearly, numerous features of the hibernation phenotype would be beneficial if they could be harnessed and applied to humans. Because superimposition of hibernating species on the mammalian phylogeny implies that the common ancestor of all mammals was a hibernator (6), the possibility of deriving useful therapies that mimic various aspects of the hibernation phenotype is within the realm of science, and not merely science fiction. The first step towards achieving this goal is to define the molecular pathways and mechanisms used during natural hibernation to orchestrate and manage their remarkable phenotypic plasticity. Because hibernation's varied phenotypes are so distinctive, it is unlikely that hypothesis-driven work based on understanding of non-hibernators will provide the transformative data needed to understand hibernation at a molecular level. Our approach to this problem is to interrogate a precisely timed set of samples from 13-lined ground squirrels representing hibernation's major physiological phenotypes for biochemical differences. Our working hypothesis is that hibernation is a cycle-within-a-cycle, with the torporarousal cycles being embedded within a summer-winter seasonal cycle. This model predicts a resetting of baseline physiology between the summer and winter modes that leads to tissue protection and that it is only in the protected winter state that torpor can be elicited. To test the predictions of this hypothesis and identify the underlying molecular mechanisms, we have collected an extensive tissue bank representing multiple timepoints throughout the year that represent key transitions in both cycles together. These samples are being examined with high-throughput 'omics' methodologies to identify the metabolites, proteins and transcripts in multiple organs that are candidates to support and drive the remarkable physiological transitions of hibernation. Early data support our model of an altered baseline physiology that separates winter from summer animals and reveal a surprising degree of tissue-specific variation that reflects unique aspects of organ function in the changes observed (1-5). [ABSTRACT FROM AUTHOR]

In the 1960s Cahill defined fasting in 3 phases with Phase II as fat using and protein conserving which is extended by animals adapted to long-term fasts without detrimental effects. Hibernation is a form of extreme fasting and black bears, Ursus americanus, undergo 5 months where they do not eat, drink, urinate or defecate while the body temperature is maintained only 5°C below normal. To accomplish this, they have a high hypothalamic set-point for fall hyperphagia and large fat reserve with a high proportion of polyunsaturated fatty acids. During transition to phase II there is elevated leptin, enhanced gut flora, decreased thyroxin and declining urea:creatinine ratios which together represent a period of fall "walking hibernation". The inhibitory effect of leptin on neuropeptide Y from the arcuate nucleus may initiate the onset of anorexia and the bear's entrance into their winter den. Bears are relatively unique in that they undergo pregnancy and lactation while fasting. There is 47% greater fat and 26% greater protein deposition for reproductive bears in the fall to offset their greater rate of mass and energy loss during denning. Long-term fasting in obese humans results in cardiac muscle protein loss and dysfunction, however, echocardiographic images of bears revealed no left ventricular resculpturing or reduced thickness during winter inactivity and chronic hypotension. Bears showed dramatic respiratory sinus arrhythmia with long pauses between breaths and profoundly depressed heart rates as low as 4 bpm. Accelerated heart rate during inhalation enhances oxygen transport within the heart tissue while the period of dramatically reduced heart rate acts to minimize energy expenditure and conserve cardiac protein. Skeletal muscle biopsies were taken from the biceps femoris, gastrocnemius and vastus lateralis during early and late denning. There was no loss of number, cross sectional area of fibers or marked transition of SO to FG fibers. Denning bears lost only about 0.03% protein/day, a value that is an order of magnitude below that reported for rats and humans, perhaps due to high ketone body inhibition of gluconeogenesis associated with a low thyroid activation of proteolysis and low urea:creatine ratio. This conservation of morphology and protein is atypical of starvation or disuse-induced skeletal muscle atrophy models. Bears underwent a period of skeletal muscle protein accretion with synthesis rates 1.4 times higher than degradation during the summer. Rates of synthesis and breakdown decreased 60-70% from summer to fall during the "walking hibernation" transition period with a concomitant 30-60% drop in RNA, a decreased ratio of RNA to DNA and an elevated δ 15N value in skeletal muscles. But all parameters then remained unchanged throughout the 5 months of denning without food or water. However, not all muscle behaves identically during fasting. There was a 4-11 % loss of protein from the gastrocnemius and biceps femoris muscle by lactating bears but no loss from the vastus lateralis. Protein synthesis could occur in a selected muscle if amino acids are made available by the marginal degradation of other skeletal muscles in concert with proteolysis of organs, collagen and smooth muscle. The collagen metabolites hydroxyproline and glycine were elevated in denned bears. In addition, proteolysis of kidney tissue releases large amounts of serine that was high in late winter. The gastrointestinal tract may also be a labile protein source as seen in an elevation of blood alpha amino acids. Winter protein demands during the Phase II fast are further reduced by: 1) no winter arousal bouts, 2) delayed implantation for pregnant females, 3) no fur growth and 4) urea nitrogen salvaging (UNS) to avoid urinary nitrogen loss. Bears recycle almost 100% of their urea, perhaps due to UTB urea transporters in the bladder and intestines which salvage urea for microbial hydrolysis in the intestine. The resulting ammonia is transported to the liver where it is reamminated into new amino acids and muscle protein. UNS is unregulated in hibernators 10-40 fold during fasting and torpor as shown by 15N labeled urea studies. Bears exhibit subtle EMG patterns throughout the denning period with peripheral vasodilation which may disperse heat and facilitate wound healing. As a result of conserved protein, fiber morphology and isometric/isotonic contraction patterns, bears during 150 days of confinement and complete food deprivation exhibit only marginal loss of strength. Muscle performance measured both in vivo and in vitro declined only 23% from early to late winter compared to a 70% loss predicted for humans confined to a hospital bed (inactive but well fed) for 150 days. Bears are truly adapted long-term fasters. [ABSTRACT FROM AUTHOR]

Hibernation under extreme cold environment needs a preparation period of some length in which most physiological functions are thought to be remodelled in wide range to adapt to hibernation. Brown adipose tissue (BAT) is an indispensable organ to complete the hibernation behavior, particularly in arousing from hibernation of hypothermia. Taking into consideration the restraint of most physiological functions by low body temperature, remodelling before hibernation occurs possibly in BAT function too. A concrete mechanism of the 'preparation' is still unclear, but the molecular-level remodelling of BAT must be performed during the preparation period of hibernation, because most gene expression stops during deep hibernation. The dominant pathway of BAT thermogenesis occurs through the β3-adrenergic receptor. We investigated the role of the β3-adrenergic system in BAT thermogenesis during arousal from hibernation both in vivo and in vitro. Necessary surgical procedures were carried out under isoflurane anesthesia. Stimulation of BAT by CL316,243 significantly facilitated arousal from hibernation and it also induced arousal in deep hibernating animals, while the β3-antagonist SR59230A inhibited arousal from hibernation. Syrian hamsters in the hibernation group (H) contained BAT that was significantly greater in overall mass, total protein, and thermogenic uncoupling protein-1 than BAT from the warm-acclimated group (WA). Although the ability of the β3-agonist CL316,243 to induce BAT thermogenesis at 36°C was no different between H and WA, its maximum ratio over the basal value at 12°C in H was significantly larger than that in WA. Forskolin, adenylyl cyclase activator, stimulation at 12°C produced equivalent BAT responses in these two groups. These results suggest that BAT in hibernating animals has potent thermogenic activity with a highly effective β3-receptor mechanism at lower temperatures. Hence we hypothesized that the high effectiveness of the receptor mechanism may be due to an increase in number of the receptor that possibly occurs during the preparation period. To investigate the hypothesis, we measured β3-receptor mRNA of BAT removed from animals in 4 stages of activity, WA, CA (cold-acclimated), H and IBA (inter-bout arousal, awake phase during hibernation) by using RT-PCR method. Gene expression of the β3-receptor in BAT of hibernating hamster was significantly smaller by about 40% and 60% than that of WA and CA respectively, but was not different from that of IBA. Results showed that the facilitation of BAT function in hibernating animals may be due to remodelling of the messenger pathway between two molecules, β3-receptor and adenylyl cyclase. [ABSTRACT FROM AUTHOR]

Hibernation is an adaptive strategy in bats that facilitates coping with low ambient temperatures (Ta) and scarce food during winter. The decline in metabolic rate (MR) and body temperature (Tb) of a bat during hibernation brings about a significant reduction in nutrients and water use, enhancing the probability of survival (Geiser and Koertner, 2010). However, hibernation is not a constant state of reduced Tb and MR, rather it comprises bouts of torpor interspersed with periods of arousal, when the animal returns to its normothermic Tb and MR (French, 1985). Although, bats arouse for only 5-10% of the time that they hibernate, arousals can account for over 85% of a hibernating bat's energy expenditure (Wang, 1978). Many different hypotheses attempting to explain periodic arousals have been proposed (Thomas and Geiser, 1997); all relate arousals to processes, such as metabolism and water loss, that vary in the same direction with Tb and Ta. Consequently, they give rise to the same prediction, namely that torpor bout length (TBL) is negatively correlated with Ta and Tb. This correlation alone cannot establish a causal link between arousal and the proposed processes, and, in addition, it introduces a difficulty in distinguishing between the hypotheses. We tested the "water balance" hypothesis, first proposed by Fisher and Manery (1967) that asserts that hibernating animals continuously lose water through evaporation while hibernating, and the ensuing dehydration initiates arousals, during which the animal rehydrates by drinking (Thomas and Geiser, 1997). We tested our hypothesis in groups of a small bat, Kuhl's pipistrelle (Pipistrellus kuhlii), that were all maintained at constant Ta and constant absolute humidity. We assumed that at constant Ta, bats have similar Tbs and MRs, and that water vapor density at the skin surface is saturated at skin temperature. We manipulated the difference in water vapor density (ew) between the skin surface (es) and the adjacent ambient air (ea) by changing ea, and measured water loss in Kuhl's pipistrelles in both dry and humid air, at constant Ta. We found that TBL and TEWL were significantly related in hibernating Kuhl's pipistrelles, independent of MR and/or Ta, supporting the water balance hypothesis, while distinguishing it from other hypotheses that relate processes correlated with MR, Ta, or both. We also found that arousal frequency during hibernation was positively related with the amount of body mass (mb) lost during this period, suggesting that bats with higher rates of TEWL that awoke more frequently lost more mb and thus end hibernation with smaller fat reserves. These results demonstrate the importance of TEWL in survival of overwintering bats. Most, if not all, temperate zone bats in both suborders, the Yangochiroptera and Yinpterochiroptera, are hibernators (Altringham, 2011). Therefore, due to the similarities in the ecological and behavioral characteristics of these animals, the possibility exists that what we found in P. kuhlii, a vespertilionid bat, may occur in other hibernating bat species of different families. [ABSTRACT FROM AUTHOR]