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Postoperative surgical site infection (SSI) is associated with high rates of disability, especially following instrumented spinal surgeries. The management of implant-associated SSI is challenging. This study analysed data from hospital databases to assess the incidence and characteristics related to postoperative SSI after posterior thoracolumbar and lumbar instrumentation. Patient demographics, infection characteristics, details of treatment and perioperative factors were reviewed (January 2010–December 2020). Oswestry Disability Index (ODI), Patient Health Questionnaire-9 (PHQ-9) and Visual Analogue Scale (VAS) scores for back and leg pain were analysed preoperatively and postoperatively until final follow-up. Of the 27,881 procedures collected from the databases, 521 (1.8%) patients were diagnosed with SSI. Of these, 191 (36.7%) patients underwent at least one revision surgery for SSI. The infection rate was significantly higher in patients with lumbar spinal stenosis than in patients with scoliosis or kyphosis (P <0.01). The most commonly isolated pathogen was meticillin-susceptible Staphylococcus aureus (43.4%). The rate of complications secondary to antibiotic treatment was 7.8%, and long-term antibiotic suppression was reported in 15.2% of patients. Instrumentation was retained in 175 (91.6%) patients, and all SSIs were controlled without recurrence during follow-up. Analysis of 27,881 patients showed an average SSI rate of 1.8%. Patients with deep wound SSI can be treated successfully in most cases with retention of instrumentation. Early diagnosis, positive revision surgery with strict irrigation, thorough debridement and a long-term course of antibiotics are critical to eradicate infection, retain implants, decrease morbidity and achieve wound healing. [ABSTRACT FROM AUTHOR]

[Display omitted] • A model has been proposed for the prediction of breakage in a high-shear mixer. • The capillary number and the pore saturation appear to be the key parameters. • Data fitted to the model is well-predicted. • The model does currently not extend to different powder-binder systems. Granule breakage is an important rate process in wet granulation that promotes product uniformity and controls product size and strength. In this work, a model to predict granule breakage is proposed and experimentally validated. The model assumes exponential of the surviving granules, dependent on a probability of breakage; a function of powder and binder properties, as well as operating parameters. Validation experiments were performed with a breakage-only granulator, filled with cohesive, non-granulating sand. Premade pellets made from lactose monohydrate and silicone oils were granulated at several impeller speeds, and the number of survivors was observed over time. The results revealed that the number of granules did indeed decay exponentially. It was found that the overall probability of breakage was inversely proportional to the capillary number. Moreover, the pore saturation played an important role in determining the probability of breakage, with higher pore saturations reducing breakage overall. A comparison with experimental data from literature revealed that the developed models agrees qualitatively with the experimental data, but is unable to fully capture the effect of powder properties and powder-binder interaction. [ABSTRACT FROM AUTHOR]

Highlights: [•] HfO2 based MIM structures are used to explore the field-effect control of BD paths. [•] Experimental results are supported by the QPC model of the post-BD conduction. [•] The results suggest the feasibility of the field-effect control through BD paths. [•] Simulations based on top of the barrier model confirm the reported field-effect. [Copyright &y& Elsevier]

Abstract: Wet granule breakage is a significant mechanism, particularly in high shear mixer granulation. This paper presents a study of the wet breakage mechanism using a Breakage Only Granulator. Granules with varying powder and liquid binder properties were created using single drop nucleation. These granules were inserted in a Breakage Only Granulator, a high shear mixer granulator with non-granulating cohesive sand as the bulk medium. Two different impellers were used at impeller speeds of 500 and 750rpm. An 11° beveled edge impeller was used to create both impact and shear in the granulator, and a flat plate impeller was used to minimize impact and maximize shear in the granulator. The fraction of granules which broke during the granulation process was used as a measure of granule breakage within the granulator. These results were compared with Stokes deformation numbers calculated using mean dynamic peak flow stresses measured in unconfined uni-axial compression tests. Results for the beveled edge impeller blade show increasing breakage with increasing Stokes deformation number. Significant breakage was observed at high Stokes deformation number. Increasing impeller speed increased the magnitude of breakage. The Stokes deformations number appears to be a reasonable predictor for granule breakage within the granulator. Results for the flat plate impeller show very little breakage at 500rpm, and significant breakage for only one formulation at 750rpm. This suggests that either impact is dominant over shear for breakage within the granulator, or that the two impeller designs give substantially different collision velocities in the granulator. The impeller speed, type and shape have a profound effect on granule breakage in high shear mixer granulators. [ABSTRACT FROM AUTHOR]

Abstract: Resultant is a classical algebraic tool for determining whether or not a polynomial systems have a common root without explicitly solving for the roots. But, the complexity of resultants can be very high in practice. In this paper, by using the theories and methods of computer algebra, two reliable algorithms for computing multi-resultant problems-Dixon resultant and Macaulay resultant were established, two new Maple procedures dixonres and macaulayres were established, too. Some examples are presented to illustrate the implementations of the programs. This would be useful for solving a system of polynomial equations. [Copyright &y& Elsevier]

Optimisation of grinding circuits is invariably dependent on sound process models together with process simulators that can solve the process models accurately. Most of the process models are solved numerically because analytical solutions are not available, which can lead to errors in the results due to the numerical approximation of mathematical equations. Whiten [1], and Valery Jnr & Morrell [2,3] have developed a dynamic model with numerical simulation for autogenous and semi-autogenous mills, and validated the model with dynamic response of mills in terms of power draw, grinding charge level, slurry level and product size distribution to changes in feed rate, feed size, feed hardness and water addition [2,3]. In this work, an analytical solution for their dynamic model of tumbling mills has been developed based on the knowledge of solutions to the first-order nonhomogeneous linear differential equations. Two algorithms, Direct Single Time method (DST) and Direct Multiple Time method (DMT), were applied to obtain the analytical solutions respectively. It was found that analytical solutions are more accurate than the traditional finite difference numerical methods. However, the DST analytical method has a drawback of numerical instability due to the accumulation of round-off errors which are amplified by exponential functions, whilst the DMT method can provide stable solutions. To test the DMT analytical method, two cases of SAG mill dynamic operation were studied with both the traditional numerical method and the newly developed analytical method, further proving the robustness and feasibility of the analytical solutions. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression of Jade-1 and β-catenin and their effect in the development of renal cell carcinoma (RCC).Methods: The expression of Jade-1 and β-catenin in 11 normal kidney tissue specimens (normal group) and 60 RCC specimens (RCC group) was determined using real-time polymerase chain reaction and immunohistochemistry. Also, their effect on early relapses of RCC was analyzed after 5 years of follow-up.Results: The expression of Jade-1 protein in the RCC group was significantly lower than that in the normal group (0.1655 vs 0.7438, P < .05), and the expression of β-catenin protein was significantly greater than that in the normal group (0.2756 vs 0.0855, P < .05). The expression of Jade-1 mRNA in the RCC group was 0.202 times that in the normal group, which were lower (P < .05). The expression of β-catenin mRNA was 1.014 times that in the normal group (P > .05). The expression of Jade-1 protein and β-catenin protein in poorly differentiated RCC specimens was significantly lower and higher than the expression in the well-differentiated RCC specimen (P < .05), respectively. Patients with negative Jade-1 expression and positive β-catenin expression were found to have shorter survival on univariate analysis (P < .05).Conclusion: RCC with a low expression of Jade-1 and high expression of β-catenin is associated with a poor outcome and decreased survival. [ABSTRACT FROM AUTHOR]

Accidental superheated liquid emissions into the atmosphere yield two-phase releases. The resulting flashing jet, driven by thermal nonequilibrium and mechanical forces, breaks up into massive droplets, fostering beneficial conditions for fire, explosion, and toxic diffusion. In this work, a 20 L tank was built to examine two-phase flow behaviors during depressurized releases of superheated liquids via a high-speed camera and phase Doppler anemometry. Different breakup regimes of flashing jet and dimensionless groups that effectively represent thermodynamic (R p Ja) and mechanical (We v Oh) driving effects were determined. Based on the interaction between the two effects, quantitative criteria to distinguish different regimes were developed. The accompanying jet characteristics, including jet angle (θ), area fraction (f A), droplet diameter (d SMD), and droplet velocity (u d), and their relationship with jet breakup were revealed. Results show that non-flashing (NFB), partially flashing (PFB), and fully flashing (FFB) breakups coincide with R p Ja (We v Oh)1/7 < 41, 41 ≤ R p Ja (We v Oh)1/7 < 223, and 223 ≤ R p Ja (We v Oh)1/7, respectively. For small-sized nozzles (d ≤3 mm), θ 2 and f A2 increase within 41 ≤ R p Ja (We v Oh)1/7 < 558 and then keep stable. The difference for large-sized nozzles resides in 223 ≤ R p Ja (We v Oh)1/7 < 558 (early FFB regime), where θ 2 and f A2 decrease slightly due to the enhanced droplet evaporation. In 41 ≤ R p Ja (We v Oh)1/7, d SMD2 decreases and u d2 increases, but at an extremely low rate within 558 ≤ R p Ja (We v Oh)1/7. [ABSTRACT FROM AUTHOR]

[Display omitted] • The breakage of single pharmaceutical tablets with different properties was investigated. • The tablet breakage patterns in an air gun was captured using an ultrahigh-speed camera. • The tablet breakage rate and amount of fines reduced with decreasing tablet porosity. • Low porosity tablets chipped while high porosity tablets disintegrated into small fragments. Milling is commonly used for controlling the size distribution of granules in the pharmaceutical dry granulation process. A thorough understanding of the breakage of single compacts is crucial in unravelling the complex interactions that exist between different pharmaceutical feed materials and the mill process conditions. However, limited studies in the literature have examined the impact breakage of single pharmaceutical compacts. In this study, pharmaceutical powders including the microcrystalline MCC 101, MCC 102 and MCC DG were compressed at different pressures and tablets with different porosities and thicknesses were produced. Impact breakage tests were conducted in an air gun and the tablet impact velocities and breakage patterns were analysed using a Phantom ultrahigh-speed camera. It was observed that the tablet breakage rate and the amount of fines reduced as the tablet porosity decreased. In addition, thin tablets with low porosity exhibited semi-brittle fracture and less intense crack propagation while thick tablets with high porosity primarily disintegrated into fine fragments. Thus, this study provides a better understanding of the breakage behaviour of different pharmaceutical materials and can potentially be used to describe the breakage modes of compacts in the ribbon milling processes. [ABSTRACT FROM AUTHOR]

• A new breakage function for PBM was validated with a variety of feed materials and ribbons. • The relationship between the PBM model parameters and ribbon porosity was established. • Good agreement was obtained between PBM and experimental granule size distribution. • The amount of fines in the milled ribbon product is linearly proportional to ribbon porosity. Dry granulation is commonly used in the pharmaceutical industry for compressing heat and moisture sensitive feed materials into compacts, subsequently followed by milling. Population balance models (PBMs) are often used to explore the effects of milling conditions on the granule size distribution (GSD) but limited studies have investigated the effects of the feed material and ribbon properties on the resulting GSD. In this work, a variety of feed materials and ribbons with different mechanical properties were used to validate a mass-based bi-modal breakage function developed in a previous study (Olaleye et al., 2019). Ribbon like tablets (referred to as ribblets) with a range of precisely controlled porosities were produced using an Instron machine and pharmaceutical excipients including the microcrystalline cellulose MCC 101, MCC DG and a DCPA/MCC mixture. Roll compacted ribbons were also produced using MCC 102 and MCC DG excipients. The ribblets and ribbons were milled in an impact-dominated cutting mill and PBM parameters were obtained from the ribblet milling data. Mechanistic models related to the feed ribbon property were then developed. It was found that the PBM with the mass-based bi-modal breakage function can accurately predict the GSDs of both the milled ribblets and roll compacted ribbons. The model developed was successfully linked to ribbon properties such as porosity for the first time and the model parameter a that reflects the fines mode in the bi-modal breakage function increased linearly with ribblet porosity. This work demonstrates the versatility of the developed PBM and provides a systematic approach for describing the ribbon milling process. [ABSTRACT FROM AUTHOR]

Effects of screw-to-roll speed ratio ϑ and roll gap S on ribbon porosity. Dry granulation through roll compaction is a technology commonly used in the pharmaceutical industry for producing roll compacted ribbons. The significance of the feed screw speed and roll speed during ribbon production was highlighted in recent publications. However, previous studies focused primarily on the individual effects of either the feed screw speed or roll speed on ribbon porosity, and the synergetic effect of these parameters was rarely examined. The aim of this study therefore was to investigate the effects of the screw-to-roll speed ratio on the porosity of roll compacted ribbons, produced at different roll compaction conditions using the microcrystalline cellulose MCC, Avicel PH-102 feed material. It was observed that ribbon porosity decreased linearly with increasing screw-to-roll speed ratio. Furthermore, an increase in the speed ratio led to an increase in the roll gap and mass throughput while a decrease in the screw constant was observed. Thus, this study demonstrates that the screw-to-roll speed ratio can be treated as one of the critical process parameters for controlling ribbon porosity and can also be used to determine the optimum operating regimes during roll compaction. [ABSTRACT FROM AUTHOR]

Abstract: Toxic ratio TR is a valuable tool in the discrimination of excess toxicity from baseline effect. Although some authors realized that internal effect concentration or critical body residual (CBR) calculated from bioconcentration factor (BCF) should be used in the TR, the effect of BCF on the discrimination of excess toxicity from baseline effect has not been investigated. In this paper, 951 acute toxicity data to fish (LC50) and 1088 BCFs were used to investigate the relationship between TR and BCF. The results showed that some compounds identified as reactive compounds exhibit excess toxicity, but some do not. BCF is closely related to TR and can significantly affect the TR value. The real excess toxicity which is used to identify reactive chemicals from baseline should be based on the toxic ratio of internal effect concentrations, rather than on the ratio of external effect concentrations, TR. The use of LC50 alone to determine TR can result in errors in TR because toxicokinetics (as estimated by the BCF) are ignored. The foundation in the discrimination of excess toxicity from baseline effect is based on the linear relationship between log BCF and hydrophobicity expressed as log KOW. However, log BCF is not linearly related with log KOW for all the compounds. The BCFs with log KOW >7 or <0 are either overestimated or underestimated by the linear baseline BCF model. Parallel lines are observed from calculated log CBR values for baseline and less inert compounds. The log BCF values overestimated or underestimated by log KOW from the baseline BCF model can result in mis-prediction and mis-classification among baseline, less inert and reactive compounds. [Copyright &y& Elsevier]

Abstract: Interspecies correlations allow the prediction of toxicity to a number of other species. However, little attention has been paid to the theoretical considerations of the interspecies relationship based on the differences of bio-uptake and toxic mechanism between species. This study examines the interspecies correlations of toxicity between species of Vibrio fischeri, river bacteria, algae, Daphnia magna, carp, Tetrahymena pyriformis, fathead minnow and guppy based on the theoretical background. The results show that there are good interspecies correlations between marine bacterium and fresh water bacteria or fish and fish. It is suggested that compounds share the same bio-uptake and toxic mechanism of action between the species. On the other hand, poor interspecies relationships were found between toxicities to algae and T. pyriformis or D. magna. It is suggested that compounds have different toxic mechanisms of action between these species. Interspecies relationships can be improved by inclusion of the octanol/water partition coefficient or the energy of the lowest unoccupied molecular orbital. They reflect the difference of bio-uptake or toxic mechanism of action between species for organic compounds. Benzoic acids show very different toxicity contributions to the three species, V. fischeri, D. magna and carp. They can be easily absorbed into the unicellular bacteria, V. fischeri. On the contrary, the skin and lipid content of multicellular organisms, such as D. magna and fish, can strongly inhibit the bio-uptake for ionizable compounds, which results in the different toxic effect between V. fischeri and D. magna or carp. Good correlation coefficients were observed between toxicities to V. fischeri and D. magna or fishes by inclusion of hydrophobic and ionization parameters. V. fischeri or D. magna can serve as a surrogate of fish toxicity for hydrophobic and ionizable compounds studied. Toxic mechanisms of action are discussed based on the theoretical background of the interspecies correlation. [Copyright &y& Elsevier]

Abstract: A large toxicity data set containing the toxicities of 250 phenols and 252 aliphatic compounds to Tetrahymena pyriformis was classified into different groups based on the structure and substituted functional groups. QSAR analysis was performed between the toxicity and calculated descriptors, expressed as hydrophobicity, polarity and ionization. Through an analysis of these class-based compounds, significant relationships were developed between the toxicity and hydrophobicity for non-polar and polar narcotic compounds. A single model for both non-polar and polar narcotics was developed by inclusion of a polar descriptor as well as the hydrophobic parameter log P. The highly hydrophobic polar narcotics can be treated as non-polar narcotics because their polar functional group(s) makes a relatively small contribution as compared to their hydrophobicity. A cut-off to classify the polar narcotics is difficult because polarity of a chemical not only depends on one or two functional groups (i.e. amino- or hydroxyl-) substituted on the compound, but also on the overall hydrophobicity of the compound. The toxicity increases with increasing the ionization by increasing the interaction between ionisable compounds and macromolecules at the target sites. However, the toxicity decreases with increasing the ionization by decreasing the bio-uptake for extremely ionisable compounds. A significant QSAR equation has been developed between the toxicity to T. pyriformis and the descriptors of hydrophobic, polarity/polarizability and ionization parameters for 457 compounds (R 2 =0.87). These compounds contain non-polar, polar and reactive compounds, and some of them are extremely ionisable. The models developed are simple, interpretable and transparent, using a small number of descriptors. [Copyright &y& Elsevier]

• A new breakage function was developed for milling of ribbons with different porosities. • The relationship between the model parameters and ribbon porosity was established. • Good agreement was obtained between the mechanistic model and experimental results. • The model is able to predict granule size distribution from ribbon milling process. Dry granulation through roll compaction followed by milling is a widely used pharmaceutical process. The material properties of powders and the roll compaction process conditions affect the strength of ribbons, and subsequently the granule size distribution (GSD). Accurate prediction of the granule size distribution from milling of ribbons with different properties is essential for ensuring tablet quality in the final compaction stage. In this study, MCC, PH-102 ribbons with precisely controlled porosities were produced and milled in a cutting mill and granule size distribution was analysed using QicPic. A population balance model with a new breakage function based on the Weibull function was developed to model the ribbon milling process. Eight model parameters were initially obtained for each ribbon porosity and very good agreement between the model and experimental results was obtained. Sensitivity analysis was then performed and thus reduced the number of model parameters that changed with ribbon porosity to two in the breakage function. The refined model was able to predict the granule size distribution both within and outside the experimental boundaries. It was shown that the model developed in this study has a great potential for predicting granule properties and therefore the optimisation of the dry granulation process. [ABSTRACT FROM AUTHOR]

Competing Interests: The authors declare that they have no conflict of interest.