Modified Cav1.4 Expression in the Cacna1fnob2 Mouse Due to Alternative Splicing of an ETn Inserted in Exon 2

The Cacna1fnob2 mouse is reported to be a naturally occurring null mutation for the Cav1.4 calcium channel gene and the phenotype of this mouse is not identical to that of the targeted gene knockout model. We found two mRNA species in the Cacna1fnob2 mouse: approximately 90% of the mRNA represents a transcript with an in-frame stop codon within exon 2 of CACNA1F, while approximately 10% of the mRNA represents a transcript in which alternative splicing within the ETn element has removed the stop codon. This latter mRNA codes for full length Cav1.4 protein, detectable by Western blot analysis that is predicted to differ from wild type Cav1.4 protein in a region of approximately 22 amino acids in the N-terminal portion of the protein. Electrophysiological analysis with either mouse Cav1.4wt or Cav1.4nob2 cDNA revealed that the alternatively spliced protein does not differ from wild type with respect to activation and inactivation characteristics; however, while the wild type N-terminus interacted with filamin proteins in a biochemical pull-down experiment, the alternatively spliced N-terminus did not. The Cacna1fnob2 mouse electroretinogram displayed reduced b-wave and oscillatory potential amplitudes, and the retina was morphologically disorganized, with substantial reduction in thickness of the outer plexiform layer and sprouting of bipolar cell dendrites ectopically into the outer nuclear layer. Nevertheless, the spatial contrast sensitivity (optokinetic response) of Cacna1fnob2 mice was generally similar to that of wild type mice. These results suggest the Cacna1fnob2 mouse is not a CACNA1F knockout model. Rather, alternative splicing within the ETn element can lead to full-length Cav1.4 protein, albeit at reduced levels, and the functional Cav1.4 mutant may be incapable of interacting with cytoskeletal filamin proteins. These changes, do not alter the ability of the Cacna1fnob2 mouse to detect and follow moving sine-wave gratings compared to their wild type counterparts

The diversity and evolution of pollination systems in large plant clades: Apocynaceae as a case study

Background and Aims Large clades of angiosperms are often characterized by diverse interactions with pollinators, but how these pollination systems are structured phylogenetically and biogeographically is still uncertain for most families. Apocynaceae is a clade of >5300 species with a worldwide distribution. A database representing >10 % of species in the family was used to explore the diversity of pollinators and evolutionary shifts in pollination systems across major clades and regions. Methods The database was compiled from published and unpublished reports. Plants were categorized into broad pollination systems and then subdivided to include bimodal systems. These were mapped against the five major divisions of the family, and against the smaller clades. Finally, pollination systems were mapped onto a phylogenetic reconstruction that included those species for which sequence data are available, and transition rates between pollination systems were calculated. Key Results Most Apocynaceae are insect pollinated with few records of bird pollination. Almost three-quarters of species are pollinated by a single higher taxon (e.g. flies or moths); 7 % have bimodal pollination systems, whilst the remaining approx. 20 % are insect generalists. The less phenotypically specialized flowers of the Rauvolfioids are pollinated by a more restricted set of pollinators than are more complex flowers within the Apocynoids + Periplocoideae + Secamonoideae + Asclepiadoideae (APSA) clade. Certain combinations of bimodal pollination systems are more common than others. Some pollination systems are missing from particular regions, whilst others are over-represented. Conclusions Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades

Spheres vs. rods in fluidized beds: Numerical and experimental investigations

For the past century, fluidized beds have been standard equipment in many branches of industry. In most applications they are used to manipulate granular and powder-like materials, whose particles can roughly be approximated as spheres. Therefore, numerical models and investigations have focused mainly on fluidized beds with spherical particles. Recent decades witnessed an increase in the use of fluidized beds in biomass processing. Unlike other materials typically used in fluidized beds, biomass is characterized by relatively large and elongated particles. For the sake of simplicity, numerical models for simulating fluidization of elongated particles have so far neglected a lot of specifics that can occur during this process and even applied the same models and conclusions that were developed for fluidization of spherical particles. The goal of this thesis is to define what is necessary for performing physically correct Computational Fluid Dynamics - Discrete Element Model (CFD-DEM) simulations of elongated particles fluidization. This thesis emphasizes the difference in fluidization between spherical and elongated particles and looks into ways to include specific particle and fluid interactions related to elongated particles into numerical (CFD-DEM) model. Results fromCFD-DEMsimulationswere validated using two experimental techniques, magnetic particle tracking (MPT) and X-ray tomography (XRT). This thesis is part of larger project of multi-scale modeling of fluidized beds with elongated particles and is focusing on the middle scale, bridging fully resolved, direct numerical simulations (DNS) with large scale, two fluid model (TFM) or multi-phase - particle in cell (MP-PIC) models, capable of simulating industrial sized fluidized beds. This thesis first looks in to the effect of including shape induced lift force and hydrodynamic torque, which were so far neglected in CFD-DEM simulations of elongated particles. It is shown that including lift force and hydrodynamic torque leads to considerable changes in the particle vertical velocity and particle preferred orientation in the fluidized bed. Looking into the mixing characteristics, as one of the most important parameters of fluidized beds, also considerable differenceswere found. Further differences in fluidization behaviour of spherical and elongated particles, as well as the effect of increasing particle aspect ratio, were shown experimentally, using MPT. Clear differences between spherical and elongated particles were found concerning the particle velocity and rotational velocity distributions. The effect of increasing particle aspect ratio and gas inlet velocity on fluidization of elongated particles was shown. Using XRT, the difference in bubbling and slugging fluidization between spherical and elongated particles was shown. In the end, the effect of newly developed multi-particle correlations for hydrodynamic forces and torque was tested, and it is concluded that they can improve the accuracy of simulations of dense fluidized beds containing elongated particles. The findings of this thesis clearly show that the models and assumptions developed for fluidization of spherical particles cannot simply be transferred to the fluidization of elongated particles. The results presented here give a new insight in the fluidization of elongated particles. They are also valuable for validation and development of larger scale models capable of simulating industrial size fluidized bed with elongated particles.Complex Fluid Processin

Spherical versus elongated particles – Numerical investigation of mixing characteristics in a gas fluidized bed

The possibility to offer good intermixing between particles is one of the main properties that make fluidized beds such an important industrial appliance. In this work, we use CFD-DEM simulations to compare mixing characteristics of spherical (AR-1) to elongated spherocylindrical particles (AR-4) of aspect ratio In simulation of AR-4 particles, single-particle and multi-particle correlations for hydrodynamic forces are tested. The results show that elongated particles have more vigorous intermixing and lower mixing times compared to spherical particles. Multi-particle correlations have a slight effect on particle mixing, and they increase the difference between AR-1 and AR-4 particles at higher gas velocities. Including hydrodynamic lift force and torque in the case of AR-4 particles leads to more vigorous mixing and lower mixing times.Complex Fluid Processin

Fluidization of elongated particles—Effect of multi-particle correlations for drag, lift, and torque in CFD-DEM

Having proper correlations for hydrodynamic forces is essential for successful CFD-DEM simulations of a fluidized bed. For spherical particles in a fluidized bed, efficient correlations for predicting the drag force, including the crowding effect caused by surrounding particles, are already available and well tested. However, for elongated particles, next to the drag force, the lift force, and hydrodynamic torque also gain importance. In this work, we apply recently developed multi-particle correlations for drag, lift and torque in CFD-DEM simulations of a fluidized bed with spherocylindrical particles of aspect ratio 4 and compare them to simulations with widely used single-particle correlations for elongated particles. Simulation results are compared with previous magnetic particle tracking experimental results. We show that multi-particle correlations improve the prediction of particle orientation and vertical velocity. We also show the importance of including hydrodynamic torque.Complex Fluid Processin

Peranan Kepala Desa dalam Pelaksanaan Pembangunan di Desa Ombarade, Kecamatan Wewewa Tengah, Kabupaten Sumba Barat Daya

The Village Head is responsible for carrying out development in his area and meeting all the needs of its citizens, one of which is the provision of public facilities through infrastructure development. The people of Ombarade Village, Southwest Sumba Regency really need facilities and infrastructure to make it easier for their people to carry out their activities. This study aims to reveal the role of the village head in the implementation of development, as well as to examine the obstacles of the village head in the implementation of development. This study was designed with empirical research using an approach to see and examine facts in the field using interview data collection techniques. The data used are primary data and secondary data. Furthermore, the data were analyzed descriptively qualitatively. The results showed that the authority of the Ombarade Village Head, Wewewa Tengah District, Southwest Sumba Regency regarding the implementation of development based on Law Number 6 of 2014, Regulation of the Minister of Home Affairs Number 114 of 2014. On the other hand, one of the inhibiting factors for village development lies in the lack of facilities. and infrastructure and supporting facilities. In addition, the lack of socialization regarding work programs or the like related to the village development process also affects the smooth implementation of village development

Effect of lift force and hydrodynamic torque on fluidisation of non-spherical particles

The aim of many industrial processes is to manipulate solid particle aggregates within gas suspensions. Prime examples of such processes include fluidised bed reactors, cyclone separators, and dust collectors. In recent years, fluidised bed reactors have been used in the gasification of biomass particles. When fluidised, these particles are subject to various hydrodynamic forces such as drag, lift and torque due to interactions with the fluid. Computational approaches, which can be used to replicate laboratory and industrial scale processes, offer a crucial method for the study of reactor design and for the formulation of optimal operating procedures. Until now, many computer models have assumed particles to be spherical whereas, in reality, biomass feedstocks typically consist of non-spherical particles. While lift and torque are of minimal importance for spherical particles, non-spherical particles experience varying lift force and torque conditions, depending on particle orientation relative to the direction of the fluid velocity. In this study, we present a numerical investigation on the effect of different lift force and torque correlations on fluidised spherocylindrical particles. We find that lift force has a significant influence on particle velocities parallel to the direction of gravity. On the other hand, particle orientation is dependent on hydrodynamic torque. Results from this numerical study provide new insight with regards to the dynamics of non-spherical particles that can be of paramount importance for industrial processes involving non-spherical particles.Complex Fluid ProcessingIntensified Reaction and Separation System

Fluidization of spherical versus elongated particles - experimental investigation using X-ray tomography

In many industrial applications, particles used in fluidized bed clearly deviate from ideal spheres. This leads to an increasing need for better understanding and developing better simulation models for fluidization of non-spherical particles. So far, the literature is quite scarce when it comes to experimental results which can be used for validation of numerical models. Also, the exact difference in fluidization behavior between spherical and elongated particles in dense fluidizing conditions is not well understood. In this work, we apply X-ray tomography to compare the fluidization behavior of a bed of a Geldart D-type spherical particles of aspect ratio 4 to that of volume equivalent spherocylindrical particles for different gas velocities. Even though the beds of both spherical and elongated particles are operating in the slugging regime, due their size and high bed height to width ratio, we see clear differences in their fluidization behavior. Our results indicate that the bed of elongated particles is slugging less than the one with spherical particles. This is indicated by a lower average bubble size in the case of elongated particles, together with a higher bubble rise velocity. The bed of elongated particles has a considerably higher distribution of small and medium bubbles. The slug waiting time distribution and slug frequency distribution indicate that a bed of elongated particles periodically switches between slugging and turbulent fluidization, unlike the bed of spherical particles which remains in the constant slugging regime.Complex Fluid ProcessingChemE/AfdelingsbureauChemE/Product and Process Engineerin