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Improving heat transfer in thermal systems has become a focus of many research studies due to the critical need for efficient waste of residual heat. The regulation of heat transfer between components in thermal systems has a direct impact on their efficiency and performance. As a result, effective heat management is critical to improving the efficiency of thermal systems and extending the life of their components. It should be noticed that baffles are important structural components widely used in various industrial applications like heat exchangers, solar collectors, electronic cooling, etc. In addition, baffles enhance fluid mixing and heat transfer behaviors. Most industrial systems do not operate in a steady state. In particular, transient phases occur during start-up and shut-down or during the control phase of controlled systems. Thus, in laminar flow, baffles induce flow unsteadiness or help the flow to bifurcate from a steady state to an unsteady flow. This paper treated the effects of different baffle shapes incorporated in channels on heat transfer rate, efficiency and friction factor in mixed and forced convection cases. Various experimental and numerical studies have been carried out on this topic to examine heat transfer enhancement compared to the flow energy. It was noticed that increasing the Reynolds number, blockage ratio and decreasing the Grashof number can achieve an increase in heat transfer. The maximum heat transfer enhancement was obtained for higher blockage ratio and higher Reynolds number in forced convective flow. The highest heat transfer improvement was obtained for the 45° angled baffles (between 150% and 850%). In mixed convective flow, the highest rate of heat transfer was obtained for transverse baffles (2.8 times compared to a similar channel with no baffles). Finally, This comprehensive review is beneficial for researchers focused on flow and heat transfer applications to use other baffle designs and fluids beyond air.

Improving heat transfer in thermal systems has become a focus of many research studies due to the critical need for efficient waste of residual heat. The regulation of heat transfer between components in thermal systems has a direct impact on their efficiency and performance. As a result, effective heat management is critical to improving the efficiency of thermal systems and extending the life of their components. It should be noticed that baffles are important structural components widely used in various industrial applications like heat exchangers, solar collectors, electronic cooling, etc. In addition, baffles enhance fluid mixing and heat transfer behaviors. Most industrial systems do not operate in a steady state. In particular, transient phases occur during start-up and shut-down or during the control phase of controlled systems. Thus, in laminar flow, baffles induce flow unsteadiness or help the flow to bifurcate from a steady state to an unsteady flow. This paper treated the effects of different baffle shapes incorporated in channels on heat transfer rate, efficiency and friction factor in mixed and forced convection cases. Various experimental and numerical studies have been carried out on this topic to examine heat transfer enhancement compared to the flow energy. It was noticed that increasing the Reynolds number, blockage ratio and decreasing the Grashof number can achieve an increase in heat transfer. The maximum heat transfer enhancement was obtained for higher blockage ratio and higher Reynolds number in forced convective flow. The highest heat transfer improvement was obtained for the 45° angled baffles (between 150% and 850%). In mixed convective flow, the highest rate of heat transfer was obtained for transverse baffles (2.8 times compared to a similar channel with no baffles). Finally, This comprehensive review is beneficial for researchers focused on flow and heat transfer applications to use other baffle designs and fluids beyond air. [ABSTRACT FROM AUTHOR]

Hypoxic pulmonary vasoconstriction (HPV) rapidly and reversibly matches lung ventilation (V) and perfusion (Q), optimizing oxygen uptake and systemic oxygen delivery. HPV occurs in small pulmonary arteries (PA), which uniquely constrict to hypoxia. Although HPV is modulated by the endothelium the core mechanism of HPV resides in PA smooth muscle cells (PASMC). The PASMC’s mitochondrial oxygen sensor lies within the electron transport chain (ETC) and includes NDUFS2 in ETC Complex-I. PASMC mitochondria respond to hypoxia by varying production of reactive oxygen species (ROS) and hydrogen peroxide in proportion to alveolar oxygen tension. Hypoxic ROS inhibition results in a state of reduction which triggers a redox-mediated inhibition of oxygen-sensitive, voltage-gated, potassium channels, including Kv1.5 and Kv2.1. Kv channel inhibition depolarizes the PASMC, opening of large-conductance calcium channels (CaL), elevating cytosolic calcium and activating the contractile apparatus. HPV is strongest in small PAs where sensors (hypoxia-responsive mitochondria) and effectors (oxygen-sensitive K+ channels) are enriched. Oxygenation at birth reverses fetal HPV, contributing to the rapid neonatal drop in pulmonary vascular resistance (PVR). A similar mitochondrial-K+ channel sensor-effector mechanism exists in the ductus arteriosus (DA), however in DASMC it is oxygen-induced increases in mitochondrial ROS that inhibit DASMC K+ channels, causing DA constriction. Atelectasis and pneumonia elicit HPV, which optimises V/Q matching, increasing systemic oxygenation. Whilst HPV in response to localized hypoxia in a single lung lobe does not increase PA pressure; global airway hypoxia, as occurs with altitude or sleep apnea, causes pulmonary hypertension. HPV can be inhibited by drugs, including calcium channel blockers, or used to maintain a dry operative field during single lung anesthesia for lung surgery. HPV does not normally cause lung edema but excessive, heterogenous HPV contributes to high altitude pulmonary edema. HPV is suppressed in COVID-19 pneumonia by a SARS-CoV-2 mitochondriopathy. HPV is a component of the body’s homeostatic oxygen sensing system. [ABSTRACT FROM AUTHOR]

Rural ecological revitalization constitutes a crucial guarantee for attaining comprehensive rural revitalization. Implementation of the strategy of carbon peaking and carbon neutrality in rural areas exerts a significant enabling role in rural ecological revitalization and green development. With low-carbon green development as the objective, this paper objectively analyzes the principal issues existing in the current rural ecological revitalization in China from the perspectives of rural environmental pollution, utilization of ecological resources, support of scientific and technological innovation, and the ecological revitalization industrial chain, and examines the connotation of promoting rural ecological revitalization against the backdrop of carbon peak and carbon neutrality. The scientific and technological innovation realization route of rural ecological revitalization is proposed from two aspects：the scientific identification of the key factors influencing rural ecological revitalization and the key content of scientific and technological innovation for rural ecological revitalization. From strengthening systematic and holistic planning and practice, guaranteeing the safety of agricultural products, insisting on moderate and high-quality coordinated development of agriculture and rural areas, developing diversified ecological industries based on local conditions, advocating integrated development of production and life ecology, and opening up policy support channels for rural ecological revitalization, the support measures and suggestions for enhancing ecological revitalization were put forward to fully exert rural ecological functions, so as to provide support for the realization of rural carbon neutrality and green high-quality sustainable development. [ABSTRACT FROM AUTHOR]

Corporate brand identity is becoming a strategic issue in the UK fashion industry, as it is complex and constantly under pressure to differentiate. Fashion brands are expanding through a range of channels and rapidly changing takeovers, and it is unclear whether internal stakeholders are aware of the possible consequences of these approaches. In particular, there appears to be no literature on how retail and wholesale brands develop and manage their corporate brand identities during these changes and whether they draw on any meaningful connections with their customers. To understand how brand architecture might support the development of brand strategies in the UK fashion industry, perceptions of corporate brand identities were explored in retail and wholesale brands. Fifteen qualitative semi-structured interviews were conducted with elite informants. The findings reveal that retail brand identities can become disconnected from their sub-brands; therefore, brand identity may be invisible to consumers, while wholesale brands maintain a strong visible brand identity dependent on the brand's values, historical legacy, innovation and positioning. A brand architecture model is developed that more accurately reflects the complex dimensions of UK fashion brands, particularly when channels expand and takeovers take place. These perspectives have not been reported in the literature. [ABSTRACT FROM AUTHOR]

This study aims to automate a geographic information system (GIS) for the conservation of irrigation canals in Casaorcco, Ayacucho - Peru. The research focuses on identifying and measuring channels of different orders using specific identification tokens. A Python script was developed to optimize data processing in ArcGIS. The results showed that the study area contains first, second, and third-order channels in various conditions. The Python script significantly accelerated data processing, improving decision-making for the conservation of irrigation canals. This study demonstrates the feasibility of automating ArcGIS GIS for more effective management of irrigation canals in Casaorcco, enhancing the conservation and maintenance of water infrastructure in the region. The implications of these findings suggest that the methodology can be applied to other regions and types of infrastructure, promoting more efficient and sustainable water resource management. [ABSTRACT FROM AUTHOR]

Wavefront shaping is a well-known method of restoring a focus deep within scattering media by manipulating the incident light. However, the achievable focus enhancement depends on and is limited by the optical and geometrical properties of the medium. These properties contribute to the number of linearly independent transmission channels for light propagating through the turbid medium. Correlations occur when the number of incident waves coupled into the scattering medium exceeds this finite number of transmission channels. This paper investigates the wavefront shaping of such correlated electric fields. The influence of the observed correlations persists even though the average electric field distribution at positions in the focal plane follows a circular complex Gaussian. We show that correlations of the transmitted electric fields reduce the achievable intensity enhancement, even deep in the turbid medium. The investigations are carried out using a Monte Carlo algorithm. It is based on the speckle statistics of independent waves and introduces correlations of neighbouring electric fields via a Cholesky decomposition of the covariance matrix. Additional investigations include scenarios where the electric fields are not completely randomized, such as for ballistic or insufficiently scattered light. Significant contributions from such little-scattered light are observed to reduce the intensity enhancement further. Data from simulations solving Maxwell's equations are compared with the results obtained from the Monte Carlo simulations for validation throughout this paper. [ABSTRACT FROM AUTHOR]

The results of long-term studies of the conjugate distribution of methane (CH4) and sulfide sulfur (Ssulfide) concentrations in the bottom sediments of watercourses of the steppe zone of the European part of Russia are analyzed. In addition to CH4 and Ssulfide, Eh and pH values, humidity and density were determined in different sediment horizons; CH4, dry residue, and pH values were determined in water. Concentrations of CH4 in the watercourses vary from <0.1 to 2007.0 μL/L (median 24.3 μL/L), with the largest number of values (72%) in the range 10.1–100.0 μL/L. The concentrations of CH4 and Ssulfide in the bottom sediments of watercourses are quite high and vary, respectively, from <0.01 to 51.0 µg/g of wet sediment (median 1.35 µg/g) and from <0.001 to 4.50 mg/g of wet sediment (median 0.813 mg/g). Usually, the CH4 and Ssulfide concentrations increase from the surface layer to the subsurface horizons, and then decrease. The difference between the distributions of Ssulfide and CH4 is the more frequent occurrence of maximum concentrations of Ssulfide in less deep sediment horizons. Seasonal changes were recorded in the vertical distribution of CH4 and Ssulfide not only in terms of their concentrations, but also in the position of maximum and minimum values. There is a weak positive correlation between the concentrations of CH4 and Ssulfide, which indicates the synchronous formation of these gases in separate layers of sediments of the studied watercourses. The positive correlation established between the CH4 concentrations in water and 0–2 cm layer of bottom sediments indicates that the sediments are an important source of CH4 in water and its emission into the atmosphere. [ABSTRACT FROM AUTHOR]

Red chili is a horticultural crop that has high economic value. In general, red chilies are used as a kitchen spice, herbal medicine, cosmetics, coloring agent and as an industrial ingredient. Red chilies are one of the centers in Sidodadi Ramunia Village, Beringin District, Deli Serdang Regency, where the red chili commodity is widely grown in this lowland area. If demand for red chili commodities increases, it will make red chili commodities one of the basic needs of society. Good and appropriate cultivation techniques are very necessary to obtain high quality production results. Red chili production will increase if red chili producers (farmers) have the skills to cultivate red chilies. This aims to analyze marketing channels, marketing margins and marketing efficiency of red chilies.The research method used is a quantitative approach and analytical descriptive methods. Sampling was carried out using the Slovin formula for farmer samples, while marketing institutions used the Snowball Sampling method. The results of this research show that in Sidodadi Ramunia village there are 2 marketing channels for red chilies, then the total marketing margin in channel I at the retailer level is IDR. 9,000/kg and the total marketing margin in channel II is IDR 13,000/kg at the collector and retailer level. The marketing efficiency of red chilies is classified as an efficient marketing channel because both channels have an efficiency value of <50%. However, the more efficient marketing channel is found in the second red chili marketing channel. [ABSTRACT FROM AUTHOR]

In order to investigate the impact of marine propeller wake fields on sediment siltation in shallow water channels, this study employs the unsteady RANS approach and the Volume of Fluid model. A full-scale numerical self-propulsion test was conducted on a 50,000 DWT oil tanker under the influence of a free surface. The research includes forecasting the effect of propeller wakes on sediment redeposition following the dredging of the approach channel to Jiaxing Port in the China Sea. Initially, uncertainty research was carried out on the full-scale ship and propeller system, and the credibility of the computational results was quantified. The simulated results based on the sediment transport numerical model were then compared and validated against actual data from monitoring stations. The self-propulsion performance and the velocity distribution of the propeller wake were examined under three different propeller speeds. Scenarios simulated included no ship navigation, daily single-ship navigation, and daily two-ship navigation, evaluating the siltation distribution within the channel over one month. The results demonstrate that ship propeller wakes positively influence the reduction of channel sedimentation, with the maximum monthly siltation reduction reaching 0.108 m during single-ship tidal navigation and 0.11 m during two-ship tidal navigation. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Teknologi dan Rekayasa Sumber Daya Air is the property of Brawijaya University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examined the effects of information providers, channels and types on the adoption of climate-resilient practices in Lesotho, deviating from the usual separate analysis of the relationships between information provider, channels and types. Previous studies have generated only partial insights into the influence of different information variables on adoption behaviour, neglecting a holistic representation of the interactive effects of all dimensions of information and adoption. Using a sample of 1,659 farmers from the Bureau of Statistics (BOS) database on the 2019/2020 agricultural production survey, the data was analysed using frequency counts, percentages and Probit regression. The results show that the majority of the farmers are male (53%), less than 30 years of age (59%), possess an education level between High School form 1 to 5 (59%), have between 5 and 10 persons per household (50%) and rely on subsistence farming as their main source of income (36%). The extension services provided, as indicated by at least 90% of the farmers, include information on farm management, crop selection, input use, credit, farm machinery, livestock, crop protection, conservation, marketing, irrigation and nutrition. In contrast, the information received is more focused on marketing, livestock production, agronomic practices, irrigation and fisheries production. The major extension service providers and sources of information are public service providers and radio. Agricultural extension information providers, channels and types influence the adoption of climate-resilient practices. The study recommends that extension information providers, channels and types be matched to specific contexts for improved effectiveness. [ABSTRACT FROM AUTHOR]

Preclinical evidence suggests that voltage gradients can act as a kind of top-down master regulator during embryogenesis and orchestrate downstream molecular-genetic pathways during organ regeneration or repair. Moreover, electrical stimulation shifts response to injury toward regeneration instead of healing or scarring. Cancer and embryogenesis not only share common phenotypical features but also commonly upregulated molecular pathways. Voltage-gated ion channel activity is directly or indirectly linked to the pathogenesis of cancer hallmarks, while experimental and clinical studies suggest that their modulation, e.g., by anesthetic agents, may exert antitumor effects. A large recent clinical trial served as a proof-of-principle for the benefit of preoperative use of topical sodium channel blockade as a potential anticancer strategy against early human breast cancers. Regardless of whether ion channel aberrations are primary or secondary cancer drivers, understanding the functional consequences of these events may guide us toward the development of novel therapeutic approaches.

Abstract Biometric systems are essential tools in modern society where most of our personal information lives in digital form. Although there is a significant variety of biometrics, electroencephalogram (EEG) signals are a useful technique to guarantee that the person is alive, they are universal, and not falsifiable. Nevertheless, EEG processing needs to address some challenges to become a viable technique to build production-ready biometric systems. These challenges include the adequate selection of features and channels that maximize the quality of the results and optimize resources. This work provides an analysis of which are the most important features and channels for the correct operation of a biometric system. The experimental analysis worked with two datasets and evaluated 19 features belonging to three groups, wavelet-based, spectral, and complexity. Five classifiers were trained: multilayer perceptron, AdaBoost, random forest, support vector machine, and K-nearest neighbors. The results found that the best feature for developing a biometric system is the standard deviation extracted from the coefficients of a three-level discrete wavelet transform. Additionally, the experimental results with the two datasets showed that the proposed method for channel selection can reduce the necessary number of channels while maintaining its performance. Our results, from one of the datasets, showed a reduction of 21 channels (from 32 to 11) and indicated that the best channels to develop biometric systems seem to be those located on the central area of the scalp.

The article presents a method for one-sided etching of channel openings in unetched microchannel plate blanks using dilute hydrofluoric acid. In this work, we used the blanks of MCP 18-10 microchannel plates. The treatment was carried out in 0.2 N hydrofluoric acid solution at room temperature without oscillating or stirring the solution. Following etching, the diameter of channel openings increased by over 10% of the diameter of MCP 18-10 channels, which increased the electron transmission of the device. [ABSTRACT FROM AUTHOR]

The shape of fins in flow channels of printed circuit heat exchangers (PCHE) significantly affects the heat exchanger performance. In the pre-cooler condition of the marine supercritical CO2 Brayton cycle power generation system, this study focuses on three typical discontinuous flow channel printed circuit heat exchangers. The investigation involves a numerical analysis of flow and heat transfer performance using CFD method. The comparative consequences illuminate that the rectangular fin channel exhibits the optimal heat transfer performance, and temperature drops are 1.18 times and 1.23 times, exceeding those of airfoil and rhombic fin channels, respectively. All three flow channels show different degrees of temperature drop reduction along the direction of fluid-flow. However, the rectangular fin channel demonstrates the worst flow performance, as pressure drops are 16.6 times and 17.8 times, higher than those of airfoil and rhombic fin channels, respectively. By calculating the values of Nu/f and Q/Δp, the comprehensive performance of each flow channel is ranked from high to low airfoil fin channel, rhombic fin channel, and rectangular fin channel. This research provides guidance for optimizing the design and applying PCHE in engineering for marine supercritical CO2 Brayton cycle pre-coolers. [ABSTRACT FROM AUTHOR]

We build on the view of the Exact Renormalization Group (ERG) as an instantiation of Optimal Transport described by a functional convection–diffusion equation. We provide a new information-theoretic perspective for understanding the ERG through the intermediary of Bayesian Statistical Inference. This connection is facilitated by the Dynamical Bayesian Inference scheme, which encodes Bayesian inference in the form of a one-parameter family of probability distributions solving an integro-differential equation derived from Bayes' law. In this note, we demonstrate how the Dynamical Bayesian Inference equation is, itself, equivalent to a diffusion equation, which we dub Bayesian Diffusion. By identifying the features that define Bayesian Diffusion and mapping them onto the features that define the ERG, we obtain a dictionary outlining how renormalization can be understood as the inverse of statistical inference. [ABSTRACT FROM AUTHOR]

Biometric systems are essential tools in modern society where most of our personal information lives in digital form. Although there is a significant variety of biometrics, electroencephalogram (EEG) signals are a useful technique to guarantee that the person is alive, they are universal, and not falsifiable. Nevertheless, EEG processing needs to address some challenges to become a viable technique to build production-ready biometric systems. These challenges include the adequate selection of features and channels that maximize the quality of the results and optimize resources. This work provides an analysis of which are the most important features and channels for the correct operation of a biometric system. The experimental analysis worked with two datasets and evaluated 19 features belonging to three groups, wavelet-based, spectral, and complexity. Five classifiers were trained: multilayer perceptron, AdaBoost, random forest, support vector machine, and K-nearest neighbors. The results found that the best feature for developing a biometric system is the standard deviation extracted from the coefficients of a three-level discrete wavelet transform. Additionally, the experimental results with the two datasets showed that the proposed method for channel selection can reduce the necessary number of channels while maintaining its performance. Our results, from one of the datasets, showed a reduction of 21 channels (from 32 to 11) and indicated that the best channels to develop biometric systems seem to be those located on the central area of the scalp. [ABSTRACT FROM AUTHOR]

Many anti-cancer drugs, such as taxanes, platinum compounds, vinca alkaloids, and proteasome inhibitors, can cause chemotherapy-induced peripheral neuropathy (CIPN). CIPN is a frequent and harmful side effect that affects the sensory, motor, and autonomic nerves, leading to pain, numbness, tingling, weakness, and reduced quality of life. The causes of CIPN are not fully known, but they involve direct nerve damage, oxidative stress, inflammation, DNA damage, microtubule dysfunction, and altered ion channel activity. CIPN is also affected by genetic, epigenetic, and environmental factors that modulate the risk and intensity of nerve damage. Currently, there are no effective treatments or prevention methods for CIPN, and symptom management is mostly symptomatic and palliative. Therefore, there is a high demand for better understanding of the cellular and molecular mechanisms involved in CIPN, as well as the development of new biomarkers and therapeutic targets. This review gives an overview of the current knowledge and challenges in the field of CIPN, focusing on the biological and molecular mechanisms underlying this disorder. [ABSTRACT FROM AUTHOR]

A method for measuring the resistive characteristics of channels in the blanks of microchannel plates was developed. Two probes were used for measurements, which minimized leakage currents through adjacent channels. The resistive properties of single channels of the microchannel insert in the reduced blank of MCP 18-10 were studied. It was established that the resistance of the channels depends on their position in the microchannel honeycomb. It was shown that the channels located in close proximity to the monolithic frame have less resistance compared to those located in the middle of a multicore glass honeycomb. [ABSTRACT FROM AUTHOR]

This study examines the influence of the Nigeria Agriculture Promotion Policy (APP) on the economic performance of small-scale palm oil marketers in Edo State. Employing a mixed-methods approach, data were collected from 110 palm oil markers across 11 local government areas (LGAs) in three senatorial districts in Edo State. Quantitative data obtained through questionnaires were analysed using descriptive statistics. Results reveal that the APP effectively enhanced the economic performance of palm oil marketers. Small-scale marketers experienced a significant income increase of 27.7%, rising from N445,072.73 in 2015 to N568,395.45 in 2021. However, the study identified certain limitations of the APP, such as the absence of regular training or skill development programs for marketers and limited access to loan facilities for procuring more efficient palm oil production machinery. These findings hold crucial implications for Nigeria's agricultural policies. The study recommends expanding market linkages at the macro level by promoting micro, small, and medium enterprises that facilitate profitable interactions between input suppliers, producers, processors, marketers, and other stakeholders within the palm oil value chains. Addressing these recommendations can foster the sustainable development of the agricultural sector in Nigeria.

In contrast to unitary evolutions, which are reversible, generic quantum processes (operations and quantum channels) are often irreversible. However, the degree of irreversibility is different for different channels, and it is desirable to have a quantitative characterization of irreversibility. In this paper, by exploiting the channel–state duality implemented by the Jamiołkowski–Choi isomorphism, we quantify the irreversibility of channels via entropy of the Jamiołkowski–Choi states of the corresponding channels and compare it with the notions of entanglement fidelity and entropy exchange. General properties of a reasonable measure of irreversibility are discussed from an intuitive perspective, and entropic measures of irreversibility are introduced. Several relations between irreversibility, entanglement fidelity, the degree of nonunitality, and decorrelating power are established. Some measures of irreversibility for a variety of prototypical channels are evaluated explicitly, revealing some information-theoretic aspects of the structure of channels from the perspective of irreversibility. [ABSTRACT FROM AUTHOR]

In this article scientific technologies for detecting qi in the living human body are reviewed. Among these electrodermal screening devices, the Apparatus for Meridian Identification (AMI) is elaborated in detail. Upon close examination of a specific AMI experiment, the data showed a significant difference between the right- and left-side Liver channels. The author concludes that this difference indicates that the right-side Liver channel passes through the Liver organ, while the left-side Liver channel does not. Further analysis of data from this experiment reveals previously unreported aspects of the relationship between the Spleen and Gall Bladder channels and the pancreas. [ABSTRACT FROM AUTHOR]

Gap junction channels are regulated by gates sensitive to cytosolic acidification and trans-junctional voltage (Vj). We propose that the chemical gate is a calmodulin (CaM) lobe. The fast-Vj gate is made primarily by the connexin's NH2-terminus domain (NT). The chemical gate closes the channel slowly and completely, while the fast-Vj gate closes the channel rapidly but incompletely. The chemical gate closes with increased cytosolic calcium concentration [Ca2+]i and with Vj gradients at Vj's negative side. In contrast, the fast-Vj gate closes at the positive or negative side of Vj depending on the connexin (Cx) type. Cxs with positively charged NT close at Vj's negative side, while those with negatively charged NT close at Vj's positive side. Cytosolic acidification alters in opposite ways the sensitivity of the fast-Vj gate: it increases the Vj sensitivity of negative gaters and decreases that of positive gaters. While the fast-Vj gate closes and opens instantaneously, the chemical gate often shows fluctuations, likely to reflect the shifting of the gate (CaM's N-lobe) in and out of the channel's pore. [ABSTRACT FROM AUTHOR]

Copyright of Estudios sobre el Mensaje Periodistico is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cone photoreceptors provide the foundation of most of human visual experience, but because they are smaller and less numerous than rods in most mammalian retinas, much less is known about their physiology. We describe new techniques and approaches which are helping to provide a better understanding of cone function. We focus on several outstanding issues, including the identification of the features of the phototransduction cascade that are responsible for the more rapid kinetics and decreased sensitivity of the cone response, the roles of inner-segment voltage-gated and Ca2+-activated channels, the means by which cones remain responsive even in the brightest illumination, mechanisms of cone visual pigment regeneration in constant light, and energy consumption of cones in comparison to that of rods.

Copyright of Food Science & Technology & Economy is the property of Grain Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Frigg Field, located in the Viking Graben of the Northern North Sea, contains complex submarine fan successions. Based on an interpretation of wellbores and seismic datasets with varying quality, previous works reported these successions to be characterized by submarine channels-infills. However, there are limited studies on the evolution history of these channels and their influence on sediment distribution. This study has combined the interpretation of wellbores and 3D seismic datasets to establish the spatial evolution of the submarine channels and their influence on sediment distribution. Petrophysical approaches, core studies and seismic attributes analysis were used to accomplish this work. Results show that the development of the Frigg fan complex was influenced by regional tectonics and sea level fluctuations that triggered sediment gravity flows. These gravity flows followed approximately N–S to NE–SW, E, and NW–SE trending submarine channels. Deposition began with the N–S to NE–SW trending channels that were followed by the eastward flowing submarine channel. The system with three major channels (NE–SW, E, and NW–SE) followed before the N–S to NE–SW trending system re-emerged. The final phase of deposition had the NE–SW, E and NW–SE trending channels. The revealed submarine channels facilitated the deposition of sediment lobes identified based on seismic attribute maps showing the geomorphology of the basin floor area during different periods. The observed geomorphological features show that the submarine channels became dominant during the deposition of the upper Frigg interval and their influence decreased toward the distal basinal areas. This suggests that the mapped submarine channels controlled sediment distribution in the study area. [ABSTRACT FROM AUTHOR]