Much research has been done on time series of financial market in last two decades using linear and non-linear correlation of the returns of stocks. In this paper, we design a method of network reconstruction for the financial market by using the insights from machine learning tool. To do so, we analyze the time series of financial indices of S&P 500 around some financial crises from 1998 to 2012 by using feature ranking approach where we use the returns of stocks in a certain day to predict the feature ranks of the next day. We use two different feature ranking approaches-Random Forest and Gradient Boosting-to rank the importance of each node for predicting the returns of each other node, which produces the feature ranking matrix. To construct threshold network, we assign a threshold which is equal to mean of the feature ranking matrix. The dynamics of network topology in threshold networks constructed by new approach can identify the financial crises covered by the monitored time series. We observe that the most influential companies during global financial crisis were in the sector of energy and financial services while during European debt crisis, the companies are in the communication services. The Shannon entropy is calculated from the feature ranking which is seen to increase over time before market crash. The rise of entropy implies the influences of stocks to each other are becoming equal, can be used as a precursor of market crash. The technique of feature ranking can be an alternative way to infer more accurate network structure for financial market than existing methods, can be used for the development of the market.New conical-shaped geometrical supramolecular H-bonded liquid crystal complexes were formed through 12 intermolecular interactions of H-bonding between flexible core (adipic acid, A) and lateral chloro-substituted azopyridines (Bn). The chains of the terminally alkoxy substituted base (n) were changed between 8 and 16 carbons. Mesomorphic and optical examinations of the prepared complexes were measured via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Fourier-transform infrared spectroscopy (FT-IR) was used to confirm the Fermi bands of the H- bonding interactions. Induced nematogenic mesophases that cover the whole lengths of alkoxy-chains were detected. The non-linear geometries of the designed supramolecular complexes were also confirmed via Density functional theory (DFT) calculations. It was found that the length of terminal alkoxy chain of the base moiety highly affects the geometrical structure of the investigated complexes. Moreover, it increases the thermodynamic energy and influences the geometrical parameters. The electrical properties of each of the acid component (A), the base (B16) and their 12 complex (A/2B16) were evaluated using the Keithley measurement-source unit. The optical properties studies showed that the influences in the optical absorption and the reduction of the energy gap of the complex compared to its individual components made the resulted supramolecular H-bonded complex soft material suitable for solar energy investigations.Animals use diverse solutions to land on vertical surfaces. Here we show the unique landing of the gliding gecko, Hemidactylus platyurus. Our high-speed video footage in the Southeast Asian rainforest capturing the first recorded, subcritical, short-range glides revealed that geckos did not markedly decrease velocity prior to impact. Unlike specialized gliders, geckos crashed head-first with the tree trunk at 6.0 ± 0.9 m/s (~140 body lengths per second) followed by an enormous pitchback of their head and torso 103 ± 34° away from the tree trunk anchored by only their hind limbs and tail. A dynamic mathematical model pointed to the utility of tails for the fall arresting response (FAR) upon landing. We tested predictions by measuring foot forces during landing of a soft, robotic physical model with an active tail reflex triggered by forefoot contact. As in wild animals, greater landing success was found for tailed robots. Experiments showed that longer tails with an active tail reflex resulted in the lower adhesive foot forces necessary for stabilizing successful landings, with a tail shortened to 25% requiring over twice the adhesive foot force.The effect of the strain on the spin and valley dependent transport properties, including the conductance and polarization, through a monolayer MoS2 superlattice under Rashba spin-orbit coupling is theoretically investigated. It is found that the conductance strongly depends on the spin and valley degrees of freedom, and spin-inversion can be achieved by MoS2 superlattice. Also, the spin and valley dependent conductance in a monolayer MoS2 superlattice can be efficiently adjusted via strain and the number of the superlattice barriers. Moreover, it is demonstrated that both the magnitude and sign of the spin and valley polarization depend on the strain strength, the number of barriers, and electrostatic barrier height. Both full spin and valley polarized current (with 100% or - 100% efficiency) can be realized in a MoS2 superlattice under strain.The function of the amyloid precursor protein (APP) is not fully understood, but its cleavage product amyloid beta (Aβ) together with neurofibrillary tangles constitute the hallmarks of Alzheimer's disease (AD). Yet, imbalance of excitatory and inhibitory neurotransmission accompanied by loss of synaptic functions, has been reported much earlier and independent of any detectable pathological markers. Recently, soluble APP fragments have been shown to bind to presynaptic GABAB receptors (GABABRs), subsequently decreasing the probability of neurotransmitter release. In this body of work, we were able to show that overexpression of wild-type human APP in mice (hAPPwt) causes early cognitive impairment, neuronal loss, and electrophysiological abnormalities in the absence of amyloid plaques and at very low levels of Aβ. hAPPwt mice exhibited neuronal overexcitation that was evident in EEG and increased long-term potentiation (LTP). Overexpression of hAPPwt did not alter GABAergic/glutamatergic receptor components or GABA production ability. Nonetheless, we detected a decrease of GABA but not glutamate that could be linked to soluble APP fragments, acting on presynaptic GABABRs and subsequently reducing GABA release. By using a specific presynaptic GABABR antagonist, we were able to rescue hyperexcitation in hAPPwt animals. Our results provide evidence that APP plays a crucial role in regulating inhibitory neurotransmission.Marsupials exhibit unique biological features that provide fascinating insights into many aspects of mammalian development. These include their distinctive mode of reproduction, altricial stage at birth, and the associated heterochrony that is required for their crawl to the pouch and teat attachment. Marsupials are also an invaluable resource for mammalian comparative biology, forming a distinct lineage from the extant placental and egg-laying monotreme mammals. Despite their unique biology, marsupial resources are lagging behind those available for placentals. The fat-tailed dunnart (Sminthopsis crassicaudata) is a laboratory based marsupial model, with simple and robust husbandry requirements and a short reproductive cycle making it amenable to experimental manipulations. Here we present a detailed staging series for the fat-tailed dunnart, focusing on their accelerated development of the forelimbs and jaws. This study provides the first skeletal developmental series on S. crassicaudata and provides a fundamental resource for future studies exploring mammalian diversification, development and evolution.Thermal management in devices directly affects their performance, but it is difficult to apply conventional cooling methods such as the use of cooling liquids or fans to micro devices owing to the small size of micro devices. In this study, we attempted to solve this problem by employing a heat sink fabricated using copper with porous structures consisting of single-layer graphene on the surface and graphene oxi de inside the pores. The porous copper/single-layer graphene/graphene oxide composite (p-Cu/G/rGO) had a porosity of approximately 35%, and the measured pore size was approximately 10 to 100 µm. The internal GO was reduced at a temperature of 1000 °C. On observing the heat distribution in the structure using a thermal imaging camera, we could observe that the p-Cu/G/rGO was conducting heat faster than the p-Cu, which was consistent with the simulation. Furthermore, the thermal resistance of p-Cu/G/rGO was lower than those of the p-Cu and pure Cu. When the p-Cu/G/rGO was fabricated into a heat sink to mount the light emitting diode (LED) chip, the measured temperature of the LED was 31.04 °C, which was less than the temperature of the pure Cu of 40.8 °C. After a week of being subjected to high power (1000 mA), the light intensity of p-Cu/G/rGO decreased to 95.24%. However, the pure Cu decreased significantly to 66.04%. The results of this study are expected to be applied to micro devices for their effective thermal management.Apolipoprotein E (ApoE) plays multiple roles in lipid transport, neuronal signaling, glucose metabolism, mitochondrial function, and inflammation in the brain. It is also associated with neurodegenerative diseases, and its influence differs depending on the isoform. In particular, the ε4 allele of APOE is the highest genetic risk factor for developing late-onset Alzheimer's disease (AD). However, the mechanism by which ApoE4 contributes to the pathogenesis of AD remains unclear. We investigated the effect of ApoE4 on autophagy in the human brains of ApoE4 carriers. Compared to non-carriers, the expression of FoxO3a regulating autophagy-related genes was significantly reduced in ApoE4 carriers, and the phosphorylation level of FoxO3a at Ser253 increased in ApoE4 carriers, indicating that FoxO3a is considerably repressed in ApoE4 carriers. As a result, the protein expression of FoxO3a downstream genes, such as Atg12, Beclin-1, BNIP3, and PINK1, was significantly decreased, likely leading to dysfunction of both autophagy and mitophagy in ApoE4 carriers. In addition, phosphorylated tau accumulated more in ApoE4 carriers than in non-carriers. Taken together, our results suggest that ApoE4 might attenuate autophagy via the repression of FoxO3a in AD pathogenesis. The regulation of the ApoE4-FoxO3a axis may provide a novel therapeutic target for the prevention and treatment of AD with the APOE4 allele. The murine postnatal leptin surge occurs within the first 4 weeks of life and is critical for neuronal projection development within hypothalamic feeding circuits. Here we describe the influence of nutritional status on the timing and magnitude of the postnatal leptin surge in mice. Plasma leptin concentrations were measured 1-3 times per week for the first 4 weeks of life in C57BL/6J pups reared in litters adjusted to 3 (small), 7-8 (normal), or 11-12 (large) pups per dam fed breeder chow or raised in litters of 7-8 by dams fed high-fat diet (HFD) ad libitum starting either prior to conception or at parturition. Mice raised in small litters become fatter than pups raised in either normal or large litters. The leptin surge in small litter pups starts earlier, lasts longer, and is dramatically larger in magnitude compared to normal litter pups, even when leptin concentrations are normalized to fat mass. https://www.selleckchem.com/MEK.html In mice reared in large litters, weight gain is diminished and the surge is both significantly delayed and lower in magnitude compared to control pups.

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