Smaller Pellet Size Research Articles

T3 Transection as a Mouse Model of Bowel Dysfunction after Spinal Cord Injury

Bowel dysfunction, in the form of constipation and/or incontinence, is one of the most prevalent and life-impacting co-morbidities associated with spinal cord injury (SCI) with no long- term treatment available. The extent to which SCI-induced changes in the colon (e.g. inflammation, fibrosis, and reduced enteric neuron density) cause progressive dysfunction is understudied. There remains a significant unmet need to develop strategies to prevent or reverse bowel dysfunction after SCI. This need remains, in part, due to the lack of a mouse model which recapitulates the human condition. We hypothesized that a T3 spinal transection in mice would trigger bowel dysfunction alongside early colonic inflammation and downstream remodeling of the colon musculature as seen in both humans and rats after SCI. Bowel dysfunction was defined as increased number of fecal pellets within the colon, smaller pellet size, and decreased water content in the stool. The number of fecal pellets within the colon increased significantly in animals receiving SCI compared to sham (laminectomy only) injuries by 4 days post injury (dpi) and persisted to 21dpi. Furthermore, fecal pellet size was significantly decreased in the SCI animals at 21dpi and trended toward decreased water content. Together, these functional measurements are indicative of chronic bowel dysfunction after T3 transection. We next molecularly interrogated whole colon tissue for inflammatory cytokine levels and found increased levels of IFN-γ at 4 dpi but not at 21dpi and found increased collagen deposition in the colonic musculature at both 4 and 21 dpi in the SCI versus sham animals. The acute spike in INF-γ and deposition of collagen after injury are consistent with our hypothesis that T3 transection causes acute inflammation followed by remodeling of the colon wall. Establishing this mouse model will enable further interrogation of cell-type specific responses and signaling pathways using transgenic models. T32 Fellowship in Physiology (GM118292) and T32 Fellowship Neurobiology of CNS Injury & Repair (5T32 NS077889) This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Sandpile modelling of dual location fuelling in fusion plasmas

We modify the Chapman sandpile model (Chapman et al 2001 Phys. Rev. Lett. 86 2814) to form comparisons with pellet pacing, which is used to reduce or eliminate ELMs in a fusion plasma. We employ a variation of that model in which a pedestal with feedback is introduced (Bowie and Hole 2018 Phys. Plasmas 25 012511), which we further modify to provide for dual fuelling—sand is added both at the centre of the sandpile, and near the edge. We observe that when the additional sand is added at the top of the pedestal, mass loss events (MLEs) are largely suppressed. While this suppression comes at a cost by way of reduction in total energy confinement, that reduction is lower than the reduction in MLE size. The trade-off between MLE suppression and reduction in energy confinement depends not only on the amount of extra sand, but also on its precise location relative to the top of the pedestal. We suggest that the approach of constant dual fuelling may be equally applicable to plasmas, and may suggest a strategy for ELM suppression in fusion plasmas. We observe that when the proposed amount of extra sand is added in ‘pellets’, using frequencies and amounts based on those proposed for ELM suppression for ITER, MLEs are similarly suppressed, although MLEs are not significantly suppressed when the pellet rate does not substantially exceed the MLE frequency. This suggests that pellet injection at the top of the pedestal at small pellet size and high frequency may represent a reasonable physical proxy for our proposed scheme. However, our results suggest that it is not the synchronisation of pellets to ELM frequencies which is the key factor for ELM suppression in this regime, but rather the introduction of additional fuelling at the top of the pedestal.

Silver Nano-Coating of Liquid Wood for Nanocomposite Manufacturing

The green composites from renewable resources are being increasingly studied because of their potential to provide benefits to the natural environment. Biotechnologies such as liquid wood injection moulding have several merits into account. Liquid wood is a thermoplastic material made from byproducts of the wood pulp industry. The liquid wood is in the form of pellets, which for processing will be melted and injected, just like plastics. This study is set to explore the potential advantages of combining liquid wood with silver nanoparticles. The use of silver-nanoparticles as antimicrobial agent is being evaluated for biomedical devices as well as furniture in many public places. In order to solve manufacturing problems in handling and spreading nano-particles in injection moulding products, an innovative methodology has been used. Plastic pellets are coated by Physical vapor deposition (PVD) with a nanometric layer of metallic silver. This continuous nanofilm produces silver nanoparticles during the plastification stage of the injection moulding process. Nano-coating fragmentation allows to distribute silver nano-platelets in the polymer matrix with very low contents and incomparable homogeneity. PVD coating has been optimized to take into account the nature of the raw material to process, mainly in terms of high-water content and small pellet size. Differential scanning calorimetry (DSC) on liquid wood granules coated with silver showed that no alteration has been produced in PVD. In fact, DSC scans show that no interaction is present between the polymer structure and the metal coating. These studies allow also a preliminary evaluation of the properties belongs of the new biomaterial, while opening for discussion the potential applications and future use in a wide variety of areas such as: bioengineering, medical and others.

A Pilot Analysis of Morphometric Assessment of Itraconazole Brands Using Dermoscopy and its Relevance in the Current Scenario.

Background:Itraconazole (ITZ) is widely used for cutaneous and systemic mycoses. Its bioavailability is inconsistent and shows interindividual variations. The quality of ITZ pellets is an important factor determining its absorption profile and thereby the therapeutic effect. Analysis of morphometric characteristics is a surrogate method to determine the same. Pellet number and size are the most important parameters in this regard.Aim:We aimed to delineate few low-cost brands, the assessed variables of which fell within the formulated criteria.Materials and Methods:In all, 22 (100 mg) formulations of ITZ were included. The pellet number was calculated manually and pellet size was determined using a dermoscope with an inbuilt measurement tool. Furthermore, size variation with respect to the innovator US Food and Drug Administration (FDA)-approved brand was determined.Results:There is a large variation in pellet number and average pellet size among different brands. Pellet number ranged from 121 to 820 and average size from 959 to 1845 μm. Few brands had dummy pellets and loose powder within the capsule. Two brands within the price range of less than Rs. 20 per capsule fulfilled the three formulated criteria: of a good pellet count, small pellet size, and low size variation. Two other brands also satisfied these criteria but were priced between Rs. 20 and 30 per capsule. The innovator US FDA-approved brand had the highest number of pellets and minimum size variation but is the costliest of all assessed brands.Limitations of the Study:We cannot comment on inter-batch variation as ours was a one-point assessment. Advanced techniques such as scanning electron microscopy and drug release profile, which would have given further useful information on pellet quality, were beyond our scope.Conclusion:There is marked variation in the assessed characteristics of ITZ formulations. These morphometric characteristics may have a significant bearing on the quality of ITZ. And thus analysis of these can help clinicians make an informed decision in choosing an ITZ formulation to achieve optimal efficacy.

Potential role of fecal microbiota from patients with slow transit constipation in the regulation of gastrointestinal motility

The gut microbiota is involved in various physiological functions, and disturbances in the host-microbiome have been proven to contribute to the dysfunction of gut; however, whether microbiota participates in the pathogenesis of constipation remains unclear. In this study, we extracted and analyzed microbiota in feces from constipated donors who had undergone effective therapy with fecal microbiota transplantation, transplanted microbiota into pseudo-germ-free mice, and measured gut motility. These mice presented with lower pellet frequency and water percentage, smaller pellet size, delayed gastrointestinal transit time, and weaker spontaneous contractions of colonic smooth muscle. To determine the mechanism underlying delayed gut motility, microbial metabolites were measured. Short chain fatty acids and secondary bile acids were decreased in mice receiving microbiota from constipated donors. Moreover, the compositional changes of gut microbiota in constipated patients were identified, including the operational taxonomic unit, and the species richness and α diversity were much greater than those in healthy volunteers. These findings suggest that alterations of the microbiome might affect gut motility via altered microbial-derived metabolites in the development of constipation, and the restoration of disturbed microbiota might improve the clinical phenotype. This study indicates that regulating the intestinal environment may be a novel therapy strategy for constipation.

Commercial catalysts screening for liquid phase nitrobenzene hydrogenation

In this work, a series of commercially available materials was screened for the catalytic hydrogenation of nitrobenzene (NB). The materials revealed different performances, particularly different activities in what concerns the NB conversion, and notably diverse selectivities towards the industrially desired reaction product, aniline (ANL). The catalysts’ active phases are based on Pd and Ni (respectively groups I and II), namely 1wt.% Pd/Al2O3 (catalyst I.1), 0.3wt.% Pd/Al2O3 (catalyst I.2), 0.3wt.% Pd/Al2O3 (catalyst I.3), and 50wt.% NiO/(Al2O3+SiO2) (catalyst II.1). The fresh and used materials were characterized by several physical-chemical techniques, specifically scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), nitrogen adsorption (with BET surface area determination), X-ray diffraction (XRD), H2 temperature-programmed reduction (TPR), inductively coupled plasma mass spectrometry (ICP-MS) and elemental (CHNS) analysis. It was shown that the catalysts are stable in the conditions studied and no deactivation was found. The characterization results allowed explaining the catalytic behavior of the tested materials. In particular, catalyst I.1 was found to be the less active, probably due to its much lower BET surface area (and larger Pd particle size). On the other hand, catalyst I.2 was the more active, which was well correlated to the smaller average particle size (along with narrower Pd particle size distribution) and smaller pellet size, although the active metal content is low. Finally, it was observed that catalyst II.1 is the most selective towards light by-products (benzene (Bz), cyclohexylamine (CHA), cyclohexanol (CHOL) and cyclohexanone (CHONA)), probably due to its lower pore size dimensions.

Comparison of different pellet injection systems for ELM pacing

ELM control in ITER is important to avoid the rapid erosion of plasma facing components (PFC) and core plasma pollution. Pacing and mitigation of ELMs can be achieved by injection of cryogenic deuterium pellets into the plasma. Successful control relies on precisely timed reliable delivery of pellets with reasonable size and velocity. To minimize unwanted fuelling constraints high speed and small pellet size seem of advantage. Efforts to develop pellet launcher systems optimised for pacing purposes have been undertaken, based on the two major accelerator types, the centrifuge and the gas or blower gun.

Increasing the shell thickness by controlling the core size of zeolite capsule catalyst: Application in iso-paraffin direct synthesis

Three kinds of H-ZSM-5 zeolite capsule catalysts were prepared on Ru/SiO 2 catalyst pellets with different size. Characterization indicated that defect-free H-ZSM-5 capsule had been constructed on the Ru/SiO 2 surface successfully. And small Ru/SiO 2 pellet with large external surface was favorable for zeolite capsule growth under the same zeolite synthesis conditions. In the iso -paraffin direct synthesis via Fischer–Tropsch synthesis (FTS) reaction, zeolite capsule catalysts, especially the one with smaller pellet size, realized the higher iso -paraffin selectivity comparing with conventional FTS Ru/SiO 2 catalyst, and physically mixed catalyst of Ru/SiO 2 with H-ZSM-5 zeolite.

Modeling of a Solid-State Polycondensation Process for the Production of PET

In the modeling of the solid-state polycondensation, the degree of dependence on the reaction step and diffusion step depends on the size of the prepolymer pellet. In other words, the model of the solid-state polycondensation processes should be a function of the size of the prepolymer pellet. In the present work a hybrid model based on the fuzzy techniques is proposed to represent simultaneously the characteristics of the reaction step and the diffusion step of the PET SSP process. The fuzzy technique was employed to take account of the “medium” particle size. The simulation results show the effectiveness of the hybrid model proposed. For the small pellet size, the hybrid model represents the behavior of the reaction-controlled step while the hybrid model depicts the behavior of the diffusion-controlled step for a large pellet size.

Significance of inoculation density control in production of polysaccharide and ganoderic acid by submerged culture of Ganoderma lucidum

Control of inoculation density was significant for cell growth, morphology, and production of polysaccharide and ganoderic acid in submerged culture of the higher fungus Ganoderma lucidum. A maximal cell concentration of 15.7 g dry cell weight (DW)/l was obtained at an inoculation density of 330 mg DW/l. For inoculation density within the range of 70–670 mg DW/l, a large inoculation density led to a small pellet size and high production of extracellular and intracellular polysaccharides, while a relatively big pellet size and high accumulation of ganoderic acid were observed at a low inoculation density. It was also shown that small pellet size resulted in high polysaccharide production, while large pellet size led to high production of ganoderic acid.

A simple form of immobilisation and its effects on morphologic trends and metabolic activity of pellet-forming microfungi

A simple form of immobilisation (support) of two pellet-form mycelial microorganisms on powdered core of maize cob is described. At a constant weight of support, the pellet number and size and, therefore, the pellet's surface to volume ratio were highly conditioned by the mean diameter of the support particles. Independently of the chemical nature of the support, an increase in surface to volume ratio produced an enhancement of the microbial metabolic activity, up to a point at which the small pellet size approximated the organisms in the culture to the filamentous form and reversed the tendency. Optimisation of the metabolic activity, with an important increase in the production of extracellular amylases, could be obtained by varying support diameter and amount per unit volume of culture.