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Objectives: During the early COVID-19 pandemic, college students had to switch to an online learning and online communication environment facing the chances of information overload, misinformation or conflicting information about COVID-19. This study aims to assess the communication needs that have arisen among college students to shed light on the development of a health communication campaign tailored toward college students. Methods: A series of 10 focus group discussions were conducted with 38 total participants. Each group has 2-6 undergraduate or graduate student participants. Nvivo was used to analyze the transcripts. Results: The students reported that they received conflicting information or misinformation. They requested messages with language that was easy to understand with infographics while being culturally appropriate. They advocated for regular and concise email updates from campus leadership. Most participants also preferred COVID-19 control and prevention information on social media. Conclusion: This study revealed the current status and the needs for health information about COVID-19 prevention and control among college students. [ABSTRACT FROM AUTHOR]

In wire electrical discharge machining (WEDM), cutting efficiency is a significant process index whose improvement has always been the research focus. Among the many factors affecting cutting efficiency, discharge energy is the most important factor. Different energy distribution form pulses were obtained by changing the peak currents at single-pulse different discharge stages. Through single-pulse discharge experiments, pulse energy distribution how to impact discharge channel motion characteristics was studied. When the energy distribution is changed through gradually increasing the peak current, an outward-pointing pressure difference will be formed inside the channel, which provides a driving force for the channel to move faster, accelerating the material erosion rate and increasing the discharge crater surface size. The cutting results reveal consistent variations in the cutting efficiency and surface size of individual discharge crater with the pulse energy distribution form. Through changing single-pulse energy distribution, the cutting efficiency can be improved by about 21%. [ABSTRACT FROM AUTHOR]

This article focuses on the advancement of fantasy policy solutions to irregular migration, drawing on the case study of the UK/French border. In 2018 people began to cross the English Channel in significant numbers to seek asylum. This led to much commentary and a raft of new legislation seeking to criminalise people crossing the Channel and end rights to seek asylum in the UK. In this article, we explore the interaction between two sets of fantasies that are advanced by politicians and mainstream political parties in the UK. That is: the liberal technocratic fantasy – that this phenomenon can be efficiently 'fixed' through interventions in policing and multilateral cooperation with neighbouring EU states; and the illiberal fantasy that extreme and performative punishments can solve it. These fantasies intersect and break at different points in time, and involve many of the same policy solutions which are represented in different terms. Importantly, both of these fantasies reproduce racialised and colonial logics and ultimately serve border imperialism. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the voltage instability in proton exchange membrane fuel cells operating at high current densities, which is important for improving their reliability and durability. Based on experimental findings regarding transparent fuel cells, a method is proposed to identify different types of voltage instability via statistical results of linear changing rate and oscillation amplitude. The types and boundaries of voltage instability are elucidated while evaluating the impact of cathode relative humidity and flow rate on voltage instability. The findings reveal that (1) the voltage instability is greatly influenced by the cathode-side relative humidity and flow rate, (2) there are three typical types of voltage instability: voltage decline, voltage oscillation, and both, and (3) voltage decline occurs at low cathode humidity, while voltage oscillation becomes more severe at large cathode humidity and low flow rate; (4) Reduction of water content in the membrane leads to voltage decline, while an increase in water content in the catalyst layer, gas diffusion layer, and channels leads to voltage oscillation. A full-condition map diagram demonstrating voltage instability during high current density conditions is presented. The method for creating this map for voltage instability will be employed to enhance fuel cell performance. [ABSTRACT FROM AUTHOR]

The micro-channel fabrication in carbon fiber-reinforced polymer (CFRP) composite through electrical discharge machining (EDM) process followed by the comprehensive study of dimensional deviation in the conceived micro-channels are presented in this work. The factors namely, voltage (V), tool rotational speed (TRS), and feed rate (FR) were considered for assessing their impact on channel width deviation (CWD). In addition to the variance analysis,, two potential metaheuristic optimizers, the Butterfly optimization algorithm (BOA) and the Spotted Hyena optimization algorithm (SHO) were used to identify the optimal operating parameters of the aforementioned process. The BOA revealed that the optimal process variables were FR = 5.99 µm/s, V = 150 volt, and TRS = 577.08 rpm for a CWD = 74.96 µm. In contrary, SHO revealed that FR = 5.99 µm/s, V = 150 volt, TRS = 542.96 rpm, and CWD = 74.53 µm were the corresponding optimal values. Overcuts were observed in the fabricated micro-channels and a detailed illustration of the mechanism of overcut formation was provided. [ABSTRACT FROM AUTHOR]

The Radar Cross Section (RCS) plays a crucial role in radar systems, serving to detect and characterize radar targets. Moreover, the need to penetrate foliage and capture images of man-made structures like roads and buildings has driven the development of very high frequency/ultra high frequency (VHF/UHF)-based radar systems. In this context, we propose a novel polyphase-coded spread spectrum (PCSS) radar system designed for RCS measurements and ISAR imaging over VHF/UHF radio channels in open environments. To provide a comprehensive understanding, we examined the open range, considering factors such as amplitude distribution function, root mean square (RMS) delay, and coherence bandwidth, followed by a link budget analysis. We also conducted a comparative study of RCS measurements to evaluate the performance of the proposed radar system, demonstrating its effectiveness through theoretical calculations. Furthermore, we assessed the radar imaging capabilities by applying the CLEAN algorithm to improve the quality of the generated images. [ABSTRACT FROM AUTHOR]

In this article, we report the design and fabrication of a 'do-it-yourself' microfluidic channel with a circular cross-section, created outside a cleanroom facility. In this approach, the fabrication of the channel do not require any chemical etching or lithography steps, making it safe and suitable for small research groups. The channel is fabricated using the soft-lithography method in polydimethylsiloxane (Sylgard® 184). A copper wire with a diameter of 240 µm is used as a mold, and the channel is created using the wire pull-out method. This work also addresses the optimal use of polydimethylsiloxane in channel fabrication, as well as the challenges faced when connecting the microchannel to the outside world via tubing and techniques to overcome them. All simulations were conducted using COMSOL Multiphysics 6.0. The analytical, simulation, and test results, show a good match. [ABSTRACT FROM AUTHOR]

This study conducts a thorough numerical analysis of a complex problem involving magnetohydrodynamic flow, radiation, activation energy, Soret, the Dufour effect, and heat transfer in a permeable channel for a Maxwell fluid. Governing equations for momentum, concentration, and heat are transformed into ordinary differential equations through a similarity transformation, enabling focused analysis. Utilizing a fourth-order Runge-Kutta scheme, we compute dimensionless velocity, temperature, and concentration fields for the steady motion of a Maxwell fluid in a channel. To ensure accuracy, our results are validated against existing research, showing excellent agreement. The study investigates the impact of various physical parameters on fluid motion, revealing insights such as decreased velocity and concentration with increased chemical reaction, and rising fluid temperature. Additionally, concentration distribution decreases with a chemical reaction and a higher Schmidt number. This research enhances understanding of complex fluid dynamics, providing valuable insights for engineering applications, particularly in industries requiring precise fluid behavior control. [ABSTRACT FROM AUTHOR]

The icing problem seriously affects the efficiency of channel water delivery in low temperature conditions. A low-temperature and long-distance channel model test platform was established to study the icing process. Through this model test platform, water temperature and formation of ice cover were tested and discussed. Furthermore, the relationship between border ice width and its influencing factors were studied quantitatively. The test results show that through the recirculating flume at a negative temperature environment, the model test platform can simulate the icing process under a long-distance water delivery situation. The water temperature decreases with the increase of delivery distance and operating time. The formation of ice cover begins from the growth of border ice; however, the static formation of ice cover is rapid, but the dynamic formation of ice cover shows an obvious process of border ice lateral growth. An equation for border ice width and ice concentration was established for prediction. [ABSTRACT FROM AUTHOR]

Enclosed depressions, termed pockmarks, are widespread seafloor morphologies, commonly associated with fluid seepage. This study provides the first detailed documentation of pockmarks offshore the South Westland margin of the South Island/Te Waipounamu, Aotearoa New Zealand. Pockmarks are identified from multibeam bathymetry (25-m grid) through manual and semi-automated selection in water depths of 100–2600 m. Pockmarks are most concentrated at 400–850 m water depth on continental slope areas between submarine canyons. A continuum of pockmark morphologies includes – (1) large (>0.5 km2 area) and irregularly shaped pockmarks above partially infilled channels; (2) small and circular pockmarks (∼100–200 m diameter; ∼0.008–0.03 km2 area) occurring between canyons; and (3) elongated and intermediate size pockmarks, generally oriented along-slope and often occurring above buried sediment waves. Elongated pockmarks appear to have been modified by near-seafloor oceanographic and/or turbidity current flows. Pockmark features occur across many locations around Aotearoa, including both the eastern and western margins. Some similar pockmark morphologies are identified in these different tectonic, sedimentary, and oceanographic settings, suggesting that there may be some similarity in formative mechanisms, but clear mechanisms leading to their formation remain enigmatic. [ABSTRACT FROM AUTHOR]

This paper conducts a state-of-the-art review for a particular emerging field of Production Research: pricing optimisation, channel and uncertainty. This is achieved by presenting a set of state-of-the-art papers accepted to this special issue, and co-word analysis to trace the development of this research field. Data for co-word analysis is based on literature search in the International Journal of Production Research, since 1961 using Web of Science with the Keywords 'pricing optimization', 'channel' or 'uncertainty'. Pricing approaches and tools have attracted more and more attentions from multiple disciplinary such as supply-chain management and marketing. The objective of this special issue is to contribute new insights to the extant body of knowledge in pricing optimisation, channel and uncertainty, specifically for 55th anniversary of International Journal of Production Research. [ABSTRACT FROM AUTHOR]

One of the most important contributions that S. George Pemberton made to the field of ichnology was the identification that burrowed firmgrounds associated with the Glossifungites Ichnofacies, commonly demarcate important sequence stratigraphic allogenic surfaces, and more recently described autogenic surfaces. This study considers an outcrop example from the Turonian Ferron Sandstone of central Utah, wherein high and low abundance monospecific suites of Glossifungites isp. are preserved landward of marginal-marine settings, recording colonization in channels under low salinity conditions. High abundances of Glossifungites isp. are associated with sloped areas of the erosional surfaces due to environmental preference, and with clay-rich underlying lithologies owing to either substrate selection or toponomy. These suites of the Glossifungites Ichnofacies demarcate surfaces at the bases of small, stacked channels encased in coastal plain strata. Stacking suggests repeated colonization related to an autogenic process. The enclosing strata and estimated position of the shoreline indicate a more landward affinity than previously reported for the ichnogenus Glossifungites, which is normally related to erosional nearshore processes or, less commonly, to offshore submarine channel development. Glossifungites-like burrows are constructed in modern freshwater settings by subaqueous insects, such as mayfly nymphs, but the trace fossil widths reported from the Ferron Sandstone are up to one and a half times larger than these modern examples. This suggests that the described trace fossils were made by marine-recruited, brackish-water crustaceans that created similar-sized burrows, or if constructed by subaqueous insects, the tracemakers were divergent in size or body plan from known modern tracemakers. [ABSTRACT FROM AUTHOR]

The fisheries sub-sector in Tanzania is challenged with limited use of Information and Communication Technology (ICT) for information gathering and dissemination. Fishers obtain fisheries information from extension officers and their fellow fishers through mainly word of mouth in physical meetings. Despite the growth in access and availability of ICT channels on Mobile phones and Internet in recent years, the fisheries sub-sector decision-makers mainly use conventional media (radio, television, personal communications) in gathering and disseminating fisheries information. Understanding the characteristics of communication channels and their effectiveness in fisheries information gathering and dissemination is of great importance. A comprehensive comparison of the six ICT channels (short message services, cellular phone call, television, radio, mobile application, and website) was done in this study using effectiveness probability. The findings from this study indicated that, short message service (SMS) and cellular phone calls are most effective for fishers. Mobile application, cellular phone calls, websites, and SMS are effective for fish traders and fisheries officers. However, the cellular phone call was not cost-effective compared to mobile applications and websites. This study recommends the development of multi-channel (SMS, web-based, and mobile application) fisheries information system to enhance fisheries information gathering and dissemination process to meet realistic information needs of all fisheries stakeholders. [ABSTRACT FROM AUTHOR]

Discharge channel motion characteristics are one of the focuses of electrical discharge machining (EDM) mechanism research. Based on single pulse discharge experiments, discharge channel motion laws of wire-cut EDM (WEDM) under different electrical parameters were researched. Results show that discharge channel motion speeds are highest at the beginning of the discharge, then drop sharply, and finally enter a relatively stable state, due to the current density change, pressure difference change between the inside and outside of the discharge channel, and the electrode wire shape itself. When discharge time lasts from 0.5 μs to 5 μs, the discharge channel average moving speed drops by about 60%, and when discharge time lasts about 15–25 μs, the discharge channel diameter expands to the maximum. Continuous machining experiment reveals that the variation laws of both cutting efficiency and a single discharge crater surface area with electrical parameters are consistent, that is, the motion laws of a single pulse discharge channel can microcosmically reveal cutting efficiency variation laws in WEDM macroscopically. Improving cutting efficiency only by increasing pulse energy (especially pulse width) is difficult. In high-speed WEDM (HSWEDM) process, the pulse width exceeding 75 μs is proved to have little effect on cutting efficiency improvement. [ABSTRACT FROM AUTHOR]

A proximal distributary channel deposit in the Turonian Ferron Sandstone of central Utah contains a trace-fossil assemblage comprised of turtle tracks (Chelonipus), vertebrate swim trace fossils (Characichnos), repichnial traces of mollusks (Archaeonassa), Rhizocorallium, and Teredolites. Mayflies are abundant producers of horizontal, spreiten, U-shaped burrows in modern freshwater channels, but rarely ascribed as producers of Rhizocorallium in the rock record. The in situ trace fossils studied are interpreted as a freshwater assemblage. Teredolites occurs within allochthonous debris reworked from stratigraphically lower brackish-water deposits. This Ferron Sandstone assemblage provides an example of the juxtaposition of freshwater ichnocoenose with exhumed brackish-water clasts. Caution must be exercised in environmental interpretation when taking into consideration both adjacent floodplain and the sedimentary structures surrounding the clasts. Complex trace-fossil relationships such as these may play a role in the scarcity of Rhizocorallium reports from freshwater deposits in the rock record, and may be more common than presently recognized. This study illustrates the importance of addressing the detailed ichnology above and below the base of channel deposits in progradational environments (e.g., delta plain), where reworked, brackish-water deposits (and bored clasts) may be entrained within overlying lower salinity facies. [ABSTRACT FROM AUTHOR]

The fabrication quality of horizontal fluid channels without supports using SLM is low, which further affects friction loss in channels. In the paper, circular fluid channels with diameters from 2 to 14 mm were built horizontally using 316L SS. The surface roughness on the top inner channel is 50–80 μm, while the rest part is approximately 10 μm. The cylindricity is around 0.2 and circularity is 0.16. The fabrication quality was significantly improved using reduced energy input with a compensation model. Friction factor measurements indicate that 75/Re is still valid in laminar flow regardless of fabrication quality. The friction factor in turbulent flow is 0.0034–0.0137, which is higher than the classical theory. Improved fabrication quality slightly reduces the friction factor. A corrected Colebrook model is developed to predict the friction factors for SLM horizontal fluid channels. Building orientation and fluid path need to be considered for reducing pressure loss. [ABSTRACT FROM AUTHOR]

This contribution reports on the field mapping of 9 exceptionally well-exposed channel-levée complexes from Taza–Guercif Basin (NE Morocco), belonging to the Late Miocene Tachrift turbidite system. Separated from each another by hemipelagic marlstones, the mapped channel-levée complexes exhibit thicknesses in the range of 5–25 m. Four main sedimentary facies associations were mapped, including channel-fill sandstones, levée thin-bedded heterolithics, chaotic mass transport deposits, and hemipelagic marlstones. In addition, two end-member styles of channel-fills spatial stacking were recognized, reflecting different modes of channel belt development and/or location along the slope profile, namely: (a) a lateral-migration pattern, resulting from lateral migration of high-sinuosity levéed channel belts, as opposed to (b) a vertically stacked pattern, interpreted to reflect the vertical aggradation of levéed channel belts with a relatively low sinuosity. The geological map accompanying this contribution provides the basis for more in-depth sedimentological investigations on the channels of the Tachrift turbidite system. [ABSTRACT FROM AUTHOR]

This article critically assesses calls for "normativity" in counter-radicalisation and counter-extremism, and suggests that aligning with hegemonic narratives about securing the "pre-crime" space is problematic in a context of emancipation. Utilising interviews with a number of Prevent officials (including Channel "de-radicalisation" mentors), the article argues that when any counter-radicalisation regime is implemented, two traits are necessarily inherent: identity construction, and "concerned concern", both of which are based on subjective speculation about an individual's future intent. Identity construction in preemptive counter-terrorism works through prejudiced human imagination in order to normalise perceived and "risky" divergence, but which is mired in contradictions precisely because practitioners interpret risk (and therefore divergence) differently. Concerned concern is a paradoxical constitution both of support for and protection against individuals. Ultimately, in exploring these two concepts, the article critically engages with the notion that Prevent is "just another safeguarding duty". Building on earlier critical terrorism scholarship, this discussion shows how worst-case logics apparent in national discourse are largely absent at the point of implementation, yet pejorative identity-construction and some suspicion (no matter how banalised) are implicit in any risk-managing scheme in a counter-terrorism context. These qualities are incompatible with an emancipatory agenda. [ABSTRACT FROM AUTHOR]

The bipolar plate (BP) is one of the main drivers of the polymer electrolyte membrane fuel cell (PEMFC) stack cost, and must also perform some critical functions simultaneously within the stack to ensure the required level of overall performance and durability. Therefore, the choice of material and production method for BPs that will meet the requirements for commercial BPs is crucial in PEMFC development. Compared to other material options such as graphite and composites, metals are more promising for the production of durable, thin, light, and low-cost BPs. However, there is still a need to reduce their processing cost through the development of cost-effective and mass production-friendly forming techniques that will not jeopardize the performance and durability of the formed plates. This paper discusses the various currently available fabrication methods for metallic BPs, with attention to their potentials for mass production and capabilities to produce plates that meet the performance and cost targets of commercial PEMFC BPs. In prospects of development drivers going forward, the potentials of hydroforming to outperform stamping for mass production of low-cost metallic plates are discussed. Current limitations facing high-quality metallic BP production and research trends are also highlighted. [ABSTRACT FROM AUTHOR]

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We describe the importance of active layer positioning for a gate electrode in organic thin-film transistors (TFTs). For this study, we utilizea numerical simulation based on 2-D Atlas, which is a two-dimensional technology computer aided design (so called 2D TCAD) software tool created by Silvaco. Variation in the electrical characteristics of pentacene TFTs is systematically explored by changing the mismatch length (LM) between the active layer and gate electrode in the bottom-gate top-contact configuration. It is found that as the LM increases, the electrical performance of pentacene TFTs is exponentially degraded in terms of drain current on/off characteristics. In particular, we explain this phenomenon by examining variations in charge distribution and gate electric field in the TFT channel region byincreasing the LM. [ABSTRACT FROM AUTHOR]

In this study, effects of embossing temperature, time, and force on production of a microfluidic device were investigated. Polymethyl methacrylate (PMMA) substrates were hot embossed by using a micromilled aluminum mold. The process parameters were altered to observe the variation of replication rate in width and depth as well as symmetry of the replicated microfluidic channels. Analysis of variance (ANOVA) on the experimental results indicated that embossing temperature was the most important process parameter, whereas embossing time and force have less impact. One distinguishing aspect of this study is that, the channels were observed to be skewed to either side of the channel depending on the location of the protrusions on the mold. The mechanism of the skewness was investigated by finite element analysis and discussed in detail. Results showed that the skewness depends on the flow characteristics of the material and could be reduced by increasing the embossing temperature. The best replication rates were obtained at parameter settings of 115°C, 10 kN, and 8 min for the molds with minimum 56 µm wide features of 120 µm depth. We also showed that the fabricated channels could be successfully sealed by solvent-assisted thermo-compressive bonding at 85°C under 5.5 kN force. [ABSTRACT FROM AUTHOR]

Oligomerization of the mixed-lineage kinase domain-like protein (MLKL) is essential for its cation channel function in necroptosis. Here we show that the MLKL channel is an octamer comprising two previously identified tetramers most likely in their side-by-side position. Intermolecule disulfide bonds are present in the tetramer but are not required for octamer assembly and necroptosis. MLKL forms oligomers in the necrosome and is then released from the necrosome before or during its membrane translocation. We identified two MLKL mutants that could not oligomerize into octamers, although they formed a tetramer, and also, one MLKL mutant could spontaneously form a disulfide bond-linked octamer. Subsequent analysis revealed that the tetramers fail to translocate to the plasma membrane and that the MLKL octamer formation depends on α-helices 4 and 5. While MLKL could be detected from outside the cells, its N- and C-terminal ends could not be detected, indicating that the MLKL octamer spans across the plasma membrane, leaving its N and C termini inside the cell. These data allowed us to propose a 180° symmetry model of the MLKL octamer and conclude that the fully assembled MLKL octamers, but not the previously described tetramers, act as effectors of necroptosis. [ABSTRACT FROM AUTHOR]

A new method for splitting droplets in a channel was presented. Two interdigital transducers were fabricated on a 1280yx-LiNbO3substrate using microelectrical technology. A poly (dimethylsiloxane) (PDMS) channel with PVC sheet and a PDMS block was mounted on the piezoelectric substrate. Surface acoustic waves were used to change the volume ratio of the split daughter droplets. Splitting experiments were done using red aqueous droplets in paraffin oil. Results show that surface acoustic waves can affect the ratio of split daughter droplets. A PDMS block in one of the daughter microchannels can obviate the remerging of daughter droplets. The work is helpful for microfluidic analysis on piezoelectric microfluidic devices. [ABSTRACT FROM AUTHOR]

In this paper a novel approach is proposed to investigate the characteristics of the plasma channel and material removal in electrochemical discharge machining (ECDM) of glass. For this purpose, a specific pulsed voltage was applied to the ECDM process to perform single discharging on the glass workpiece. In this way, a voltage slightly lower than the critical voltage was applied as the offset voltage. Meanwhile the working voltages above the critical voltage were applied to the process in a specific period of time to produce single sparks. The signatures of the single sparks on the workpiece surface were used to determine the characteristics of the plasma channel. According to the results, the average diameter of 260 µm was achieved for the plasma channel in the glass machining conditions. This paper also reports a thermophysical model for material removal in ECDM process based on the finite element method (FEM) and plasma channel diameter achieved in this study. The amount of the removed material as well as the diameter and depth of the crater, achieved by the FEM, was measured and compared with the experimental outcomes. The results demonstrate the consistency of the proposed model with the experimental observations. [ABSTRACT FROM PUBLISHER]

Experimental analysis is conducted in order to estimate the distribution of air (gas) flow velocity in the advanced six-channel cyclone with spiral shell, and to measure the resistance and purifying effectiveness of the cyclone with spiral shell. The device is used for separating the minuscule solid particles from contaminated air (gas) flow. The multifunctional measuring instrument TESTO-452 with the attachedPito-Prandtltube was used for carrying out the experiments. The air (gas) velocity in all six-cyclone channels, the resistance of six-channel cyclone with spiral shell and the effectiveness of air (gas) flow purification, depending on the position of curvilinear semi-rings and the average air (gas) flow velocity in the cyclone channels, were measured during the experiments. [ABSTRACT FROM PUBLISHER]

The purpose of this study is to evaluate the behavior and mechanism of a debris flow on various slopes through numerical simulation. The numerical simulation consisted of using equations related to mass conservation and momentum conservation in order to consider erosion and deposition, and the Finite Difference Method was applied. As the inflow water discharge in the upstream of the channel increases, the curve of the water discharge exhibits instability and, as time passes, the fluctuation of the high water discharge continues. In regions where the mountain areas and the ocean are connected, it is deduced that the high level of sediment concentration can greatly affect the environment surrounding the ocean. The numerical model of this study was applied in Kangwon Province of South Korea. The results show that when the debris flow reaches downstream, the flow discharge and water flow depth increase. Erosion occurs more than deposition and much of the sediment runs off downstream. The result of the simulation performed at point of sediment discharge runoff is 114,216m3. This study will provide useful information in predicting disasters caused by debris flow and in planning for various countermeasures to prevent debris-flow-related disasters. [ABSTRACT FROM PUBLISHER]

This study assessed the barriers to the use of radio as a channel of agricultural information by farmers in Ushongo local government area of Benue State, Nigeria. One hundred thirty-two (132) respondents were selected using purposive and random sampling techniques. Data were collected using a structured questionnaire. The results revealed that the respondents have more access to Ashi Waves FM, and their preferred format for radio programmes is radio drama. The major barrier to the use of radio is poor signals from radio stations. Logistic regression statistics showed that age and family size significantly affect respondents’ level of access to radio. It is recommended that radio progammes be presented in drama format and Ashi Waves FM be used to convey information to farmers. Also, radio stations are encouraged to install efficient transmitters. [ABSTRACT FROM PUBLISHER]

“She is of good behaviour and a good Muslim. Against this background, I accept on the evidence before me that this defendant gathered together the contents of the SD card in order to explore and understand the charges which her brothers faced. There is no evidence that she was motivated by their ideology or was preparing to follow them.” The judge in the case of Umm Ahmed clarified to the court that she had not been involved in illegality or had any intention to pose a threat to the UK. Despite this recognition, he sentenced Begum to a 12-month prison term for possessing the magazineInspirewhich she had been reading to understand her charged brother’s case. What is unknown is the story of how Umm Ahmed was subjected to a deradicalisation programme, under the auspices of PREVENT and CHANNEL, without any indication of actual involvement in terrorism. The use of deradicalisation narratives in schools, universities and hospitals has led to the criminalisation of large sections of the various Muslim communities in the UK. Based on our experience of cases such as Umm Ahmed, we hope to present a view of how an aggressive anti-Muslim narrative that is based on assumptions subverts the political expression/identity of individuals by turning them into potential threats. The advocacy group CAGE has been working with Umm Ahmed in order to highlight the abuse of the terrorism narrative in her case, but also to understand the actual implementation of PREVENT and CHANNEL beyond their conceptual promotion as a safeguarding tool. By understanding the everyday interactions with PREVENT, a picture can be formed of the way that a false presentation of narratives can lead to a person becoming an “extremist” or “terrorist”, while the truth may lie in a completely alternative place. [ABSTRACT FROM PUBLISHER]

Progressive-pressure electrolyte flow is employed to improve efficiency and accuracy of radial electrochemical machining of blisk channels. Flow field simulation indicates that the use of progressive-pressure flow gives a high electrolyte flow rate in the inter-electrode gap, allowing a high cathode feed rate without shortcut. Experiments show that the high feed rate leads to high machining efficiency. Under the progressive-pressure flow, the surface roughnesses of the convex part, concave part, and hub of channels are reduced and the machining accuracy of the hub is enhanced. Furthermore, the allowances of the hub can be reduced by using progressive-pressure electrolyte flow. [ABSTRACT FROM PUBLISHER]

We consider a nematic liquid crystal flowing in converging and divergent channels delimited by two intersecting solid planes forming angular sector region. There is a source or sink of nematic, at the planes intersection, whether the nematic flow is outwards or inwards. We find the planar multiple configurations of the director of the nematic satisfying in-plane planar hard-anchoring boundary conditions for 4′-n-pentyl-4-cyanobiphenyl (5CB). Also, we obtain the corresponding velocity profiles parametrised by the Reynolds number for non-slip boundary conditions. We have obtained both symmetric and asymmetric velocity profiles for outwards and inwards flows, nevertheless, none of these profiles has counterflows regions as it occurs for isotropic liquids. Finally, we calculate the mass rate and Frank’s elastic energy for the same multiple velocity profiles and nematic textures we found. We hope this model can be useful as an extreme confining case which helps to understand the industrially important processes of blade coating and cavity filling of liquid crystalline materials. [ABSTRACT FROM AUTHOR]

This article argues that Prevent, Britain’s counter-radicalisation policy, has been an important and under-analysed site for contemporary renegotiations of threat; first, in that it seeks to act on threats existing within a radically unknowable future, and second, in terms of how it identifies those subjects seen to represent this future threat. In its ambition to tame this radical contingency, Prevent represents an extension of governmentality that acts at the level of potential, before the threat being targeted has come to exist. It does so by mediating these unknowable futures through ascriptions of identification, values and the danger it sees posed by disassociations from “Britishness” and then intervenes in the present, both pre-emptively through community cohesion and at a precautionary level through the Channel programme. What is at stake is the (re)generation and the policing of the boundaries of secured life, and ultimately, it will be argued, the possibilities of contemporary politics. [ABSTRACT FROM PUBLISHER]

This article presents the results of a laboratory investigation of the mechanisms of surfactant-enhanced air sparging (SEAS) in different media. Two kinds of media (medium sand and gravel) were used in one-dimensional column experiments, designed to determine (1) the functional relationship between the air saturation and surface tension of water during SEAS, and (2) the contaminant removal mechanisms in different air travel modes (channels and bubbles) under different surface tension values. The results demonstrated that when air traveled in the form of channels, a decrease in surface tension accordingly reduced capillary pressure in porous media. Air saturation therefore increased, thereby considerably improving contaminant removal. The variations in removal efficiency under different surface tension values coincide with the trend of air saturation change. When air traveled in the form of bubbles, the SEAS-induced air saturation in the column was directly affected by foam stability and foamability, rather than by the surface tension of water. Surfactant addition improved only the contaminant removal rate, but the decrease in lingering concentration was insignificant. The results of this study can serve as theoretical bases for SEAS application in contaminated sites. [ABSTRACT FROM AUTHOR]

Slip flow occurs in a wide variety of practical chemical engineering processes. This work models, for the first time, the interaction of surface slip and system rotation normal to the flow direction. It is found that the flow fields are affected considerably. For Poiseuille flow, slip increases the longitudinal flow rate at low rotation, but decreases it at high rotation. For Couette flow, slip decreases the longitudinal drag. The solutions are also exact solutions of the Navier-Stokes equations. [ABSTRACT FROM PUBLISHER]

Influence of phosphorus doping in the a-Si:H layer with various deposition time and phosphine gas flow rate in hydrogenated amorphous silicon thin film transistor (a-Si:H TFT) has been investigated. The a-SiN:H layer, the phosphorus doped a-Si:H layer and the n+ a-Si:H layer were deposited by plasma enhanced chemical vapor deposition (PECVD) using SiH4, PH3, Ar, H2 and NH3 gases. Proper phosphorus doping in the a-Si:H layer affected the channel of the a-Si:H TFT and improved the characteristics. Also, the field effect mobility was increased from 0.22 to 0.61 cm2/V·s. The characteristics of phosphorus doping in the a-Si:H TFT were investigated and compared with the conventional a-Si:H TFT. [ABSTRACT FROM PUBLISHER]

Polymer electrolyte membrane fuel cell (PEMFC) stacks are widely studied for their own advantages. The flow maldistribution in unit cells may severely influence the fuel cell stack performance, mainly including the uniformity of current density and the voltage. Investigations of flow maldistribution in PEMFC stacks are rarely found, and presented results are unsystematic, scattered, and even contradictory. Thus, it is necessary to review and summarize the previous concerned papers, and to get some methods or guidelines for reducing the flow maldistribution in PEMFC stacks. In this paper, the existing literature concerning flow maldistributions in PEMFC stacks is reviewed. The effects of the arrangement of flow configurations, design parameters, and operating conditions on the flow maldistribution are discussed. Some suggestions are outlined to reduce the flow maldistribution in PEMFC stacks. The need for further research is also discussed. [ABSTRACT FROM AUTHOR]

We study theoretically the incompressible, viscous, oscillatory hydromagnetic Couette flow in a horizontal fluid-saturated highly permeable porous medium parallel-plate channel rotating about an axis perpendicular to the plane of the plates under the action of a uniform magnetic field, B0, inclined at an angle θ to the axis of rotation. The flow is generated by the non-torsional oscillation of the lower plate of the channel. The reduced unsteady momentum equations are nondimensionalized with appropriate variables. Exact solutions under specified boundary conditions are obtained using the Laplace transform method (LTM). The flow regime is found to be controlled by a rotational parameter (K2), which is the reciprocal of the Ekman number (Ek), the square of the Hartmann magnetohydrodynamic number (M2), a porous medium permeability parameter (Kp), which is the inverse of the Darcy number (Da), oscillation frequency (ω), dimensionless time (T), and magnetic field inclination (θ). The influence of these parameters on the primary (u1) and secondary (v1) velocity field is presented graphically and studied in detail. Asymptotic behavior of the solutions is also examined for several cases of the square of the Hartmann number, rotation parameter, and oscillation angular frequency. The existence of modified Hartmann boundary layers is also identified. The present study has important applications in MHD (magnetohydrodynamic) energy generator flows, chemical engineering magnetic materials processing, conducting blood flows, and process fluid dynamics. [ABSTRACT FROM AUTHOR]

The current research attempts to investigate the use of the two sources of dealers' soft channel power (i.e., expert power and referent power) as a means of achieving three desirable channel relationship outcomes in Zimbabwe's channel of distribution system. The field study is conducted in Harare and Chitungwiza, and research data are collected from 447 small and medium-size enterprise (SME) manufacturers. Dealers' expert power and referent power are found to be important sources of channel power that positively influence SME manufacturers' trust, relationship commitment, and relationship satisfaction. It is concluded that managers in dealers' firms can improve their channel relationships with SME manfacturers if they acquire or enhance their expert power and referent power. [ABSTRACT FROM AUTHOR]

Given a noisy communication channel γ, the aim of this paper is to investigate γ-decodable codes and γ-correctable codes. Examples are given for channels with possible errors caused by deletions. The γ-correctability does not imply γ-decodability but ensures error recovery. In general, the properties of γ-correctability and γ-decodability have little in common. Some general properties concerning γ-decodable codes and γ-correctable codes are derived. Moreover, we propose a special kind of codes called γ-separable codes having a unique decodability. [ABSTRACT FROM AUTHOR]

An approximated analytical solution of the Navier-Stokes equations describing the laminar flow through a three-dimensional rectangular channel with wall suction or injection is presented. The solution is developed in terms of a stream function whose variation is described by a separation approach in combination with the polynomial approximation of the spatial velocity profiles. The approximated profiles agree well with simulated results obtained from the commercial code ANSYS CFX 10. [ABSTRACT FROM AUTHOR]

Results are presented from both linear stability analysis and numerical simulations of three-dimensional nonlinear convection in a Boussinesq fluid in an annular channel, under experimental boundary conditions, rotating about a vertical axis uniformly heated from below. The focus is placed on the Prandtl number Pr = 7.0, representing liquid water at room temperature. The linear analysis shows that, when the aspect ratio is sufficiently small, there exists only one stationary mode that occupies the whole fluid container. When the aspect ratio is moderate or large, however, there exist three different linear solutions: (i) the outer sidewall-localized traveling wave propagating against the sense of rotation; (ii) the inner sidewall-localized traveling wave propagating in the same sense as rotation; and (iii) both the counter-traveling waves occurring simultaneously. Guided by the result of the linear stability analysis, fully three-dimensional simulations are then performed for a channel with a moderate aspect ratio. It is found that neither the prograde nor the retrograde mode is physically realizable near threshold and beyond. The dynamics of nonlinear convection in a rotating channel are chiefly characterized by the interaction between the sidewall-localized waves and the interior convection cells/rolls, producing an interesting and unusual nonlinear phenomenon. In order to compare with the classical Rayleigh-Benard problem without vertical sidewalls, we also study linear and nonlinear convection at exactly the same parameters but in an infinitely extended layer with periodic horizontal conditions. This reveals that both the linear instability and nonlinear convection in a rotating channel are characteristically different from those in a rotating layer with periodic horizontal conditions. [ABSTRACT FROM AUTHOR]

A 3-D vanadium-manganese phosphate, [C4H12N2]2MnII(VVO2)2( [image omitted]O2)(PO4)4(H2O)4 (1), was synthesized hydrothermally and characterized by single crystal X-ray diffraction. This complex crystallizes in the triclinic system with the space group P1 and cell parameters a = 7.070(2) Å, b = 12.356(4) Å, c = 17.120(6) Å, α = 75.698(9)°, β = 85.651(12)°, γ = 78.331(10)°, and Z = 2. The 3-D vanadium-manganese phosphate formed from VIV octahedral chains and VV-MnII-VV clusters, which are linked via PO4 tetrahedra. Complex 1 contains channels in three directions in which diprotonated piperazine ions and water molecules reside. Characterization by element analysis, IR, XPS, fluorescence spectrum, and TG analysis are also described. [ABSTRACT FROM AUTHOR]

A 3D coordination polymer with 1D hexagonal channels of [KMn4(IDC)3(prz)· 3H2O]n (1) (H3IDC = imidazole-4,5-dicarboxylic acid, prz = piperazine) was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic with four independent Mn(II) atoms. The IDC3 - anions alternately bridge the Mn(2) and Mn(4) cations to form a 1D infinite linear chain, which is connected by the Mn(1) and Mn(3) through IDC3 - ligands to generate a concertina sheet. The sheets are further interlinked by IDC3 - ligands to form 3D frameworks with 1D hexagonal channels (7.251 × 8.677 Å), which is occupied by water molecules and K+ ions. Magnetic susceptibility measurements of 1 exhibit antiferromagnetic interactions between the nearest Mn(II) atoms. [ABSTRACT FROM AUTHOR]

The electrophysiological technique of patch-clamp was used to characterize the pore properties of site-directed mutants in the Vibrio cholerae general diffusion porin OmpU. Changes in conductance and selectivity were observed, thus confirming the predicted pore location of these residues, based on homology with the Escherichia coli porins OmpF and OmpC. Some mutants acquire a weak selectivity for cations, which mirrors the properties of the homologous, deoxycholic acid sensitive, OmpT porin of V. cholerae. However, the mutants remain insensitive to deoxycholic acid, like wildtype OmpU. This result suggests that channel selectivity is not an important determinant in the sensitivity to this drug, and is in agreement with our finding that the neutral deoxycholic acid, and not deoxycholate, is the actual active form in channel block. Modifications in the kinetics of spontaneous closures were also noted, and are similar to those found for the E. coli channels. In addition, mutants at the D116 residue on the L3 loop display marked transitions to sub-conductance states. The results reported here are compared to a phenotypical characterization of the mutants in terms of permeability to maltodextrins and β-lactam antibiotic sensitivity. No strict correlations are observed, suggesting that distinct, but somewhat overlapping, molecular determinants control electrophysiological properties and substrate permeability. [ABSTRACT FROM AUTHOR]

A 3D porous coordination polymer with 1D open nanotubular channel has been constructed hydrothermally using Zn(II) and planar rigid ligand IDC3 -(imidazole-4,5-dicarboxylic acid). The channels are occupied by water molecules. The compound displays strong blue fluorescent emission at room temperature. [ABSTRACT FROM AUTHOR]

HTTP is a key application-level protocol in enabling Internet services. The trend of network convergence and mobile accessibility brings new challenges to the protocol. This paper describes the design and implementation of an architecture for Java-based HTTP input channel for multi-access wireless network. An HTTP input channel can adapt its behavior according to the changing network status in a context-aware fashion. The adaptation includes both selecting and dynamically switching the underlying connection used, as well as coping with disconnection situation. The adaptation is performed at channel level instead of device level, so that multiple connections in one user device can be utilized simultaneously. Experiments were performed in a GPRS-WLAN integrated environment to demonstrate the operational correctness of the architecture. Performance metrics were measured and analyzed. [ABSTRACT FROM AUTHOR]

An inorganic-organic hybrid compound {[Cu(phen)3]2PW11VO40 · 2H2O (1) has been hydrothermally prepared and structurally characterized by elemental analyses, IR, CV, TG, magnetic susceptibility measurements and single crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group C2/c with a = 27.232(2) Å, b = 25.351(2) Å, c = 16.2748 (4) Å, β = 105.20°, V = 10842.3 Å3, Z = 4, R1 = 0.0490 and wR2 = 0.1362. The structure of 1 exhibits a three-dimensional supramolecular network, formed by hydrogen-bonding and π-π stacking interactions. The three-dimensional network consists of one-dimensional honeycomb channels, which accommodate free water molecules. The size of the channel is 10.4 × 10.4 Å. Electrochemistry of 1 shows it undergoes three one-electron reversible redox processes. Variable-temperature magnetic measurements show typical antiferromagnetic interactions in the 2-300 K temperature range. [ABSTRACT FROM AUTHOR]

The behaviour of cations in nanopores plays an important role in transport processes in the biological and industrial membranes, porous electrodes, ion channels, and nanomaterials in general. Molecular dynamics simulations have been carried out to study the selectivity mechanism of nanopores by studying the ion permeation events through non-charged carbon nanotubes (10,0) which have an effective diameter of 0.4374 nm. We have investigated pure NaCl, pure KCl and equimolar mixture of NaCl and KCl (50/50) aqueous solutions. Our results show that a membrane of uncharged nanotubes of the appropriate diameter can select K+ against Na+ without the presence of external electric field or surface charges. The key to the ion selectivity is that Na+-H2O clusters are more stable than K+-H2O clusters, and Na+ ions have higher desolvation energy than K+ ions. When both Na+ and K+ are present in the same solution, there is a competition between the two types of cations and the nanotubes select K+ over Na+.We also studied the effects of temperature and pressure to find the conditions, which permit Na+ to permeate through the nanotubes. [ABSTRACT FROM AUTHOR]

Water is probably the most important molecule in biology. It solvates molecules, all biochemical reactions occur in it and it is a major driving force in protein folding. Phospholipid membranes separate different water environments, but connections do exist between the different compartments. The integral membrane proteins (IMPs) form these connections. In the case of ions, IMPs form the passageways that regulate ion movement across the membrane. Structural information from three ion distinct channels are examined to see how these channels first select for and then control the movement of their target ions. This review focuses on how these channels select for target ions and control their movement while taking into account and using different properties of water. This includes the use of hydrophobic gates, mimicking the water environment, and controlling ions indirectly by controlling water. [ABSTRACT FROM AUTHOR]

The loss of phosphorous (P) from the landscape is commonly viewed as deleterious for surface water quality. However, the quantities lost and the impact this can have on surface waters depends on numerous mechanisms that occur whilst en route. The aim of this review is to give an outline of these mechanisms and thus how sources of P in the agricultural landscape are connected to the impairment of surface water quality. Processes are dealt with by examining the potential for P loss from the landscape and its availability to aquatic plants during flow overland and subsurface flow and once in streamflow or a lake or reservoir. By examining the connectivity between P loss and the impact on surface water quality, potential mitigation and management of P losses are discussed for various aquatic systems. [ABSTRACT FROM AUTHOR]