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Pacific salmon (Oncorhynchus spp.) are exposed to environmental and anthropogenic stresses due to their wide geographic distribution, long migrations, and complex life histories. Understanding how these stressors interact to affect population abundance is essential for conservation and sustainable management of salmon. We investigate the causal effects on population dynamics of hatchery-enhanced Japanese chum salmon (O. keta), focusing on the period of sharp decline since the early 2000s and the rebound in 2022. We used 50 years of fishery and hatchery release data and 40 years of high-resolution SST datasets in 30 coastal areas in Japan, as well as monthly mean SST data along the Japanese chum salmon migration route in the high seas. We provide initial evidence that SST at release and that in the migration route, size at release, northward expansion of a piscivorous fish, and intraspecific competition influence the abundance of Japanese chum salmon. The sudden increase in 2022 was driven by an increase in Age-4 fish. The age structure shift towards younger age at maturity was observed in all areas except the Honshu Pacific and was particularly pronounced in the Hokkaido Sea of Japan and the Sea of Okhotsk and, where winter SST in the North Pacific and the Gulf of Alaska had a positive effect on return rates. Size at release and Russian chum salmon also had a positive effect. On the other hand, SST at release and yellowtail (Seriola quinqueradiata), as well as summer SST in the Sea of Okhotsk had a negative effect on return rate. Our regression model predicted the return rate well, while explaining 43-75% of the variation in regional populations. Our results highlight winter SST as a driver of younger age at maturity but the trade-off between returned fish and body size.

Ionic liquids can retard the perovskite crystallization with the aim to form compact films with larger and more uniformly distributed grain size. The ionic liquid driven crystallization is exploited to prepared a record planar perovskite solar cell with stabilized power output of 19.5%.

Abstract Energy storage is equally important as energy production. The modern human society demands lightweight, flexible, inexpensive and environment friendly energy storage systems. Batteries are the major energy storage devices, but slow charge-discharge rate, short life cycles and bulkiness of battery limit its applications in portable and wearable devices. Lately, supercapacitors have been receiving a great attention as alternative energy storage devices because of their distinctive features such as high power density, light weight, fast charging-discharging rate, secure operation and long life span. Supercapacitors, also called electrochemical capacitors, are already being used in various applications such as hybrid vehicles, power back up, military services and portable electronics like laptops, mobile phones, wrist watches, wearable devices, roll-up displays, electronic papers, etc. The materials utilized in the supercapacitors play a prominent role, because the performance of supercapacitors depends on its properties. Specific capacitance of a supercapacitor depends on the surface area and the pore size distribution of the electrode material used for its fabrication. Compared with the transition metal oxides and conducting polymers, carbon and its different types provide larger surface area. However, this high surface area of carbon is not completely accessible for the electrolyte. In this context, metal oxide nanostructures are considered quite attractive candidates in energy storage applications due to their unique properties. Metal oxide nanostructures based energy storage devices have been shown to exhibit superior electrochemical performance due to their high surface to volume ratio and high mechanical flexibilities. The supercapacitor performance depends on morphology and oxidation state of metal oxide. Metal oxides such as RuO2, MnO2, TiO2, NiO, CoO, CuO, and composite materials are potential candidates for supercapacitor applications. RuO2 and MnO2 are the prominent electrode materials due to higher energy density with higher theoretical capacitance of about 1450 and 1270 F/g, respectively. RuO2 limits its utilization being scarce, extremely expensive (5000/- @1g) and toxic to some extent. At the same time MnO2 has its own benefits like cheap material cost, plentiful availability in the earth’s crust, and environmental friendliness. However, the conductivity of MnO2 is much lower ranging from 10-7 to10-3 S/cm. The main advantage of MnO2 is that it shows much higher specific capacitance with aqueous electrolytes as compared to other gel or solid electrolytes. But associated with this advantage is the problem that MnO2 is soluble in water and cell becomes dead after a few charging and discharging cycles. The previous reported studies suggest that MnO2 electrode supercapacitors (when material is synthesised by hydrothermal method without a surfactant) show low cyclic stability and specific capacitance. Triethanolamine (TEA) is a good surfactant for synthesis of metal oxides but has not been used for synthesis of MnO2. It is possible to synthesise MnO­2 nanostructures with desirable crystalline structures and morphology using TEA as surfactant, which won’t dissolve in water over high number of charge-discharge cycles. The aim of this study is to synthesize the metal oxide based manganese nanostructure material to explore its applicability as the electrode in supercapacitor. For this, b-MnO2 nanostructures have been synthesized via TEA assisted hydrothermal method at different reaction temperatures. Silver doped MnO2 nanocomposite and Carbon-MnO2 composite electrode materials have also been synthesized by hydrothermal method expecting enhanced electrochemical performance of the cell. The structural and crystallite size study of the materials have been carried out using X- ray diffraction (XRD). The morphological studies have been carried out by using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). X-ray Photoelectron Spectroscopy (XPS) analysis is performed for material purity, quantity and binding energy of those elements that are present within the top 1-12 nm of the sample surface. Fourier Transform Infrared Spectroscopy (FTIR) investigation has been undertaken to identify the functional groups in the material. Supercapacitors have been fabricated using the electrodes which are prepared with the various synthesized β-MnO2 and its composite materials. The electrochemical performance has been tested with three different analytical tools including cyclic voltammetry, galvanostatic charge discharge and electrochemical impedance spectroscopy. XRD data of MnO2 samples are in agreement with JCPDS card no. 81-2261, which suggests the formation of β-MnO2 tetragonal planes with lattice parameters a = b = 4.3985 Å and c = 2.8701 Å. The intensity of the diffraction peaks is found to increase as the synthesis temperature is increased from 60℃ to 120. XPS analysis of β-MnO2 sample synthesised at 120℃ reveals the surface oxidation state of manganese with Mn4+ 2P3/2 and Mn4+ 2P1/2 peaks located at 642.1 eV and 652.5 eV. SEM micrographs suggested that the temperature of synthesis affects the surface morphology and nanorods structure of MnO2 and that the high surface area and porous β-MnO2 nanorods are developed by hydrothermal synthesis at the reaction temperature near 100℃. The porosity of the nanostructures assists in better ion transportation in the electrode and improves the contact area for electrolyte ions to perform rapid surface redox reactions. Selected Area Electron Diffraction (SAED) pattern of β-MnO2 showed crystal planes at (110), (101), (210), (220), and (301) with interplanar spacing 3.109 Å, 2.403 Å, 1.959 Å, 1.555 Å, and 1.300 Å, respectively in agreement with the results obtained from XRD. FTIR exhibited the MnO2 vibrational bands at 707.1 and 529.2 cm-1. As expected, the β-MnO2 nanorods analysed as supercapacitor electrode in 1M Na2SO4 liquid electrolyte exhibited high specific capacitance of 89.63, 128.05, 461.59 and 288.72 F/g at a scan rate of 10 mV/s (on a wide potential window of 0-0.8 V) for the sample synthesized at temperatures 60℃, 80℃, 100℃ and 120℃, respectively. The best performance is observed for electrode of the MnO2 synthesised at 100℃, which can be attributed to large surface area (due to larger size nanorods) available for charge-storage and for redox-reactions (pseudocapacitive type of charge-storage). The energy densities recorded are 7.11, 10.55, 38.89 and 30.67 Wh/Kg at a power density of 0.4 kW/Kg. The morphological analysis of Ag doped MnO2 performed by SEM revealed a particle size of about 50 nm. The highest specific capacitance is found to be 523.91 F/g at the scan rate 10 mV/s (on a potential window of 0-0.8 V). Doping of Ag in MnO2 increases the specific capacitance of the supercapacitor as compared to pure MnO2 nanorods. Carbon-MnO2 supercapacitor has given specific capacitance value (560 F/g at scan rate 10 mV/s on a potential window of 0-0.8 V) which is even higher than AgMnO2 electrode based symmetric supercapacitor. The specific capacitance increases as carbon has higher surface area leading to increased adsorption of ions on the surface of electrode. The thesis also suggests various extended research options like different electrolytes, other electrode materials and fabrication of asymmetric supercapacitors aiming at further enhanced and desirable characteristics.

Alcohol-induced muscle disease (AIMD) is a composite term to describe any muscle pathology (molecular, biochemical, structural or physiological) resulting from either acute or chronic alcohol ingestion or a combination thereof. The chronic form of AIMD is arguably the most prevalent skeletal muscle disorder in the Western Hemisphere affecting more than 2000 subjects per 100,000 population and is thus much more common than hereditary disorders such as Becker or Duchenne muscular dystrophy. Paradoxically, most texts on skeletal myopathies or scientific meetings covering muscle disease have generally ignored chronic alcoholic myopathy. The chronic form of AIMDs affects 40-60% of alcoholics and is more common than other alcohol-induced diseases, for example, cirrhosis (15-20% of chronic alcoholics), peripheral neuropathy (15-20%), intestinal disease (30-50%) or cardiomyopathy (15-35%). In this article, we summarise the pathological features of alcoholic muscle disease, particularly biochemical changes related to protein metabolism and some of the putative underlying mechanisms. However, the intervening steps between the exposure of muscle to ethanol and the initiation of the cascade of responses leading to muscle weakness and loss of muscle bulk remain essentially unknown. We argue that alcoholic myopathy represents: (a) a model system in which both the causal agent and the target organ is known; (b) a myopathy involving free-radical mediated pathology to the whole body which may also target skeletal muscle and (c) a reversible myopathy, unlike many hereditary muscle diseases. A clearer understanding of the mechanisms responsible for alcoholic myopathy is important since some of the underlying pathways may be common to other myopathies.

The most commonly known renewable energy sources include the wind, wave, hydroelectric, biomass, and solar energy. Photovoltaic cells are divided into three main categories and referred to as generations of photovoltaic cells. The first generation of photovoltaic includes the monocrystalline silicon and multicrystalline silicon based solar cells. The second generation solar cells include amorphous silicon-based thin film solar cells - cadmium telluride/cadmium sulfide (CdTe/CdS) solar cells and copper indium gallium selenide (CIGS) solar cells. In third generation solar cells, the electrolyte plays a vital role in deciding the power conversion efficiency as well as stability. Liquid electrolytes are the conventional type of electrolyte and the most widely used transport medium. Polymer electrolytes are ionic conductors prepared by the dissolution of salts in a suitable polymer. Polymer electrolytes are divided into solid polymer electrolyte (SPE), gel polymer electrolyte (GPE) and composite polymer electrolyte (CPE).

An important topic in Monte Carlo neutron transport calculations is to verify that the statistics of the calculated estimates are correct. Undersampling, non-converged fission source distribution and inter-cycle correlations may result in inaccurate results. In this paper, we study the effect of the number of neutron histories on the distributions of homogenized group constants and assembly discontinuity factors generated using Serpent 2 Monte Carlo code. We apply two normality tests and a so-called "drift-in-mean" test to the batch-wise distributions of selected parameters generated for two assembly types taken from the MIT BEAVRS benchmark. The results imply that in the tested cases the batch-wise estimates of the studied group constants can be regarded as normally distributed. We also show that undersampling is an issue with the calculated assembly discontinuity factors when the number of neutron histories is small.