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Balamuthia mandrillaris – a brief overview of the parasite causing encephalitis
No full textBalamuthia mandrillaris is a unicellular protist, known to cause infection of the central nervous system. The life cycle of B. mandrillaris is divided into vegetative, infectious trophozoites and dormant cysts. The ability of B. mandrillaris to produce a rare but fatal infection has resulted in considerable interest in this parasite by the scientific community. However, the pathogenic mechanisms remain incompletely understood. Additionally, symptoms vary from patient to patient, hence diagnosis is often delayed. This delay in diagnosis is compounded further with limited availability of expertise or tools for diagnosis resulting in symptom-based personalized therapy, nonetheless, the prognosis remains extremely poor. Recent studies have shown the use of nanomedicine as a promising approach against parasitic infections such as B. mandrillaris. This, together with the availability of whole genome sequence information, coupled with high throughput genomics-based approaches to make B. mandrillaris genetically tractable should be of interest to study its molecular pathogenetic mechanisms and as a model organism to study cellular differentiation, growth, motility, and biochemical pathways. Overall, future research should move beyond the descriptive pathology of Balamuthia infection towards a mechanistic understanding of host entry, blood-brain barrier traversal, neuronal damage, immune evasion, and cyst biology
A group-theoretic approach to elimination measurements of qubit sequences
No full textMost measurements are designed to tell you which of several alternatives have occurred, but it is also possible to make measurements that eliminate possibilities and tell you an alternative that did not occur. Measurements of this type have proven useful in quantum foundations and in quantum cryptography. Here we show how group theory can be used to design such measurements. This requires that the set of states being considered possesses a symmetry described by a group. After some general considerations, we focus on the case of measurements on two-qubit states that eliminate one state. We then move on to construct measurements that eliminate two three-qubit states and four four-qubit states. The sets of states eliminated constitute cosets of a subgroup. A condition that constrains the construction of elimination measurements is then presented. Finally, in an appendix, we briefly consider the case of elimination measurements with failure probabilities and an elimination measurement on n-qubit states
3D Printing in the Construction Sector: Identification of Key Topics, Technologies, Applications and Relevant Factors Discussed in the Literature
No full text3D printing is transforming the construction industry by reducing material waste, enhancing design flexibility, and shortening construction timelines. As a rapidly advancing technology, it offers innovative solutions for efficient, sustainable, and advanced building practices. This study aims to give an overview of the contents treated in the literature on 3D printing of concrete, with a focus on key topics, technologies, applications, and parameters influencing printability. Following a systematic review process, 1079 studies were analyzed in terms of objectives, structural applications, and printing technologies. The findings reveal a strong emphasis on parameters such as strength, interlayer bonding, and rheological properties, while durability-related aspects like freeze-thaw resistance and water absorption are explored more seldom. The study underscores the need for material optimization to balance fresh-state and hardened-state properties, ensure long-term structural performance, and incorporate sustainable materials. By addressing these gaps, this research identifies critical pathways for advancing 3D printing in construction and provides recommendations for achieving durable, efficient, and environmentally sustainable solutions
Analysis and synthesis denoisers for forward-backward plug-and-play algorithms
No full textIn this work we study the behavior of the forward-backward (FB) algorithm when the proximity operator is replaced by a sub-iterative procedure to approximate a Gaussian denoiser, in a Plug-and-Play (PnP) fashion. In particular, we consider both analysis and synthesis Gaussian denoisers within a dictionary framework, obtained by unrolling dual-FB iterations or FB iterations, respectively. We analyze the associated minimization problems as well as the asymptotic behavior of the resulting FB-PnP iterations. In particular, we show that the synthesis Gaussian denoising problem can be viewed as a proximity operator. For each case, analysis and synthesis, we show that the FB-PnP algorithms solve the same problem whether we use only one or an infinite number of sub-iteration to solve the denoising problem at each iteration. To this aim, we show that each "one sub-iteration" strategy within the FB-PnP can be interpreted as a primal-dual algorithm when a warm-restart strategy is used. We further present similar results when using a Moreau-Yosida smoothing of the global problem, for an arbitrary number of sub-iterations. Finally, we provide numerical simulations to illustrate our theoretical results. In particular we first consider a toy compressive sensing example, as well as an image restoration problem in a deep dictionary framework
Fault interruption scheme for HVDC systems using GaN-HEMT and VCB
No full textPower electronics switching devices played an important role in high-voltage DC circuit breaker development. Timely isolation of faulty portions of an HVDC transmission line from a healthy system is a basic requirement for a fault interruption. In this scenario, the integration of hybrid DC circuit breakers (HDCCBs) with wideband-gap semiconductor devices enables the effective management of high power, currents, and voltages. The SiC-MESFET and the GaN-HEMT are commonly used wideband-gap-based semiconductor devices. This paper introduces a fault interruption scheme for HVDC power systems, featuring the advancement of a hybrid DC circuit breaker. The proposed HDCCB design consists of two parts, one part is based on a VCB as a mechanical circuit breaker, and the second part involves electronic switches for fault interruption. The electronic switches are designed through the combination of GaN and HEMT to achieve fast switching to achieve rapid interruption of fault current. The system model is implemented through a Simulink model to perform a comparative analysis between the presented and existing protection topologies. Current commutation is achieved through the attainment of artificial zero current crossing to interrupt the DC fault. GaN-HEMT emerges as a more reliable and fast switching element compared to other electronic switches like Sic-MESFET as validated by the presented simulative results. The presented model shows better fault-clearing times of 2.2 ms and 2 ms for experimental parameters of (500 kV and 9kA) and (100 kV and 10kA), respectively. This fault-clearing time shows an improvement of 52.38% and 50% compared to the SiC-MESFET-based electronic switches used by the existing mechanisms. The outcomes of the proposed design are evaluated in terms of fault current, commutated current, and voltage across the commutated capacitor.</p
The deep structure of the Pernambuco Plateau, Northeast Brazil, and its implications for Equatorial Atlantic rifting
No full textThe Pernambuco Plateau Basin (PPB) of northeastern Brazil contains an important record of continental rifting at the boundary between the major South Atlantic basins and the Equatorial Atlantic Gateway (EAG). The geology and structure of the PPB is described using high quality long-offset multi-channel seismic data. The deep seismic imaging reported here shows that the PPB is not thick continental crust with a thin sediment veneer but thinned continental crust with half grabens in which sediment thicknesses reaches in excess of 3 km. Within these deep grabens we find large halokinetic structures in the form of salt diapirs and pillows that root into the early syn-rift. Sub-marine volcanic edifices are also clearly imaged, the oldest of which have bases close to the syn-to-post rift transition. We discuss the PPB evolution integrating the implications of the newly observed evidence for syn-rift salt deposition and early post-rift sub-marine volcanic activity as well as a reanalysis of recent plate models. The proposed best fit model has PPB rifting in the Aptian and early Albian, with final break-up relatively late in the Albian
A Novel Spatio-Temporal Rate-Splitting-based Power Allocation Optimization Strategy for RIS-assisted 6G MU-MISO Communication Systems
No full textReconfigurable intelligent surfaces (RISs) can dynamically adjust phase shifts to achieve scalability in networks, while rate-splitting multiple access (RSMA) can dynamically allocate spectrum and power resources according to the communication needs of IoT devices and reduce the energy consumption of the system. Therefore, the integration of RIS and RSMA can not only enhance the performance of IoT communication systems, but also reduces wastage of limited resources. This paper proposes a novel spatio-temporal rate-splitting-based power allocation optimization strategy for RIS-assisted multi-user (MU) systems to maximize channel capacity and energy efficiency gains. Leveraging the proposed spatio-temporal minimum mean squared error (STMMSE) principle and the rate splitting-based optimal power consumption (RS-OPC) method, the approach considers the Cramér-Rao bound for channel errors and derives expressions for maximizing channel capacity and obtaining the optimal solution. The proposed method selectively adjusts power values for different users and transmission types of symbols to achieve optimal power allocation objectives, thereby ensuring communication quality while optimizing channel capacity. This offers communication systems a higher configurability and resource optimization. Extensive simulation results including channel capacity, energy efficiency (EE) and spectral efficiency (SE) validate the effectiveness of the proposed method
High Moisture Extrusion Based Texturization and Functional Modulation of Pea Protein Isolate through Integration with Cultivated Beef
No full textThe increasing global demand for meat can be sustainably leveraged by alternative protein, but the inferior quality of current plant-based meat analogues has somewhat disillusioned consumers. Small inclusion level of cultivated beef (CB) to bulk pea protein isolate in the high moisture extrusion (HME) showed a process unlock how to modulate the texture and instrumental sensory properties of the hybrid pea protein extrudates. Such novel co-extrusion delivered improved physicochemical and flavour properties as well as imparted distinct change in texture and microstructure. A comparison between hybrid pea protein extrudates with 10% CB (E-PCB10) and 2% CB (E-PCB2) showed a clear enhancement of the water holding (∼16.7-fold) and oil holding (∼67-fold) capacities in E-CPB10 and the instrumental sensory analyses also showed up to 30% reduction of key off-flavour markers of pea protein in E-PCB10 along with reduction in bitterness and astringency. E-PCB10 and E-PCB2 exhibit different microstructure compared to E-PPI, and E-PCB10 showed increased hardness, resilience, cohesiveness and chewiness as well as the mechanical strength. The scanning electron microscopy of extrudates revealed that higher concentrations of cultivated beef disrupted the pea protein matrix and the laminar structure in E-PPI becomes less easy to discern in E-PCB2 and E-PCB10. The increasing percentage of CB leads to a more enhanced protein-protein cross-linking in E-PCB10. These findings demonstrated for the first time that an addition of as little as 2% and 10% of cultivated beef can modulate the texture and microstructure of pea protein extrudate. This could lead to a promising texturization process for plant protein via microstructure modulation, reducing off-taste, and enhancing functional features to develop high-quality, hybrid alternative protein-based meat analogue
Origins and fate of polycyclic aromatic hydrocarbons (PAHs) in sustainable drainage systems (SuDS) in a Scottish urban area: Implications for groundwater systems
No full textIncreasing urbanisation and the effects of climate change have resulted in a decrease in water quality and availability worldwide. At the same time, flooding in urban areas has become one of the most prevalent natural disasters worldwide. Sustainable drainage systems (SuDS) are resilient stormwater management solutions that can help reduce flooding by mimicking natural drainage processes and promoting infiltration. Numerous studies have focused on the benefits SuDS provide. But, to date, studies fail to investigate the risks that detention basins pose to groundwater quality, particularly the potential for infiltration of stormwater pollutants such as polycyclic aromatic hydrocarbons (PAHs). To address this important knowledge gap, this study combines gas chromatography–mass spectrometry (GC–MS) techniques for PAHs characterisation with numerical modelling tools to investigate organic pollutant infiltration patterns. We find that high levels of PAHs originating from urban areas are temporarily stored in SuDS basins and are likely to reach shallow water tables within one year. Multiple factors such as vegetation, precipitation, drainage area size, total organic carbon content in the soil and soil saturation influence the PAHs infiltration rates within the basins. More broadly, this study highlights the need for more research regarding SuDS dynamics to prevent both flooding and groundwater deterioration.<br/
Seamounts of Cabo Verde: A review of their ecological and economic significance, anthropogenic impacts, and conservation needs
No full textThe deep-sea areas of the Cabo Verde Archipelago remain largely unexplored, with seamounts standing out as the most prominent and abundant geomorphological features. The ecological significance of these underwater structures is well-documented in various regions of the planet, as they often serve as biodiversity hotspots, stepping stones for species connectivity and, in some cases, areas with high levels of endemism. However, the biology and ecology of the seamounts around Cabo Verde are still largely unknown. Preliminary studies of the geomorphology, oceanographic characteristics and ecology of specific features suggest that the Cabo Verde seamount network — comprising 14 known conspicuous seamounts as well as smaller elevations less than 1000 m — harbours high biological diversity. That biodiversity associated with the Cabo Verde seamounts spans a wide range of forms, from microscopic organisms to cetaceans, encompassing both pelagic and benthic communities. Commercial activities associated with seamounts, in particular fishing, are a critical aspect to consider for ecosystem management. Evaluating their current uses, future prospects, and the existing and potential threats the Cabo Verde seamounts face is essential for effective and sustainable marine spatial planning. This study reviews and synthesises the current knowledge on the Cabo Verde seamounts within its Exclusive Economic Zone (EEZ), focusing on their environmental and biological aspects, including geology, oceanography, and associated biological communities. Key topics include primary production, zooplankton communities, benthic organisms, large vertebrates such as elasmobranchs, sea turtles, seabirds, and cetaceans, as well as microbes and trophic linkages. Additionally, this review explores the socio-economic dimensions linked to seamounts, highlighting their importance to the local economy and emphasizing the need for effective marine spatial management plans. These considerations are crucial for balancing conservation efforts with sustainable use, ensuring the long-term health of these vital underwater ecosystems.</p
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