Household liquidity and incremental financing decisions:theory and evidence

In this paper we develop a stochastic model for household liquidity. In the model, the optimal liquidity policy takes the form of a liquidity range. Subsequently, we use the model to calibrate the upper bound of the predicted liquidity range. Equipped with knowledge about the relevant control barriers, we run a series of empirical tests on a panel data set of Dutch households covering the period 1992-2007. The results broadly validate our theoretical predictions that households (i) exhaust most of their short-term liquid assets prior to increasing net debt, and (ii) reduce outstanding net debt at the optimally selected upper liquidity barrier. However, a small minority of households appear to act sub-optimally. Poor and vulnerable households rely too frequently on expensive forms of credit (such as overdrafts) hereby incurring substantial amounts of fees and fixed borrowing costs. Elderly households and people on social benefits tend to accumulate too much liquidity. Finally, some households take on expensive short-term credit while having substantial amounts of low-yielding liquid assets

Characterization of a β-glucanase produced by Rhizopus microsporus var. microsporus, and its potential for application in the brewing industry

BACKGROUND: In the barley malting process, partial hydrolysis of β-glucans begins with seed germination. However, the endogenous 1,3-1,4-β-glucanases are heat inactivated, and the remaining high molecular weight β-glucans may cause severe problems such as increased brewer mash viscosity and turbidity. Increased viscosity impairs pumping and filtration, resulting in lower efficiency, reduced yields of extracts, and lower filtration rates, as well as the appearance of gelatinous precipitates in the finished beer. Therefore, the use of exogenous β-glucanases to reduce the β-glucans already present in the malt barley is highly desirable. RESULTS: The zygomycete microfungus Rhizopus microsporus var. microsporus secreted substantial amounts of β-glucanase in liquid culture medium containing 0.5% chitin. An active protein was isolated by gel filtration and ion exchange chromatographies of the β-glucanase activity-containing culture supernatant. This isolated protein hydrolyzed 1,3-1,4-β-glucan (barley β-glucan), but showed only residual activity against 1,3-β-glucan (laminarin), or no activity at all against 1,4-β-glucan (cellulose), indicating that the R. microsporus var. microsporus enzyme is a member of the EC 3.2.1.73 category. The purified protein had a molecular mass of 33.7 kDa, as determined by mass spectrometry. The optimal pH and temperature for hydrolysis of 1,3-1,4-β-glucan were in the ranges of 4–5, and 50–60°C, respectively. The Km and Vmax values for hydrolysis of β-glucan at pH 5.0 and 50°C were 22.39 mg.mL(-1 )and 16.46 mg.min(-1), respectively. The purified enzyme was highly sensitive to Cu(+2), but showed less or no sensitivity to other divalent ions, and was able to reduce both the viscosity and the filtration time of a sample of brewer mash. In comparison to the values determined for the mash treated with two commercial glucanases, the relative viscosity value for the mash treated with the 1,3-1,4-β-glucanase produced by R. microsporus var. microsporus. was determined to be consistently lower. CONCLUSION: The zygomycete microfungus R. microsporus var. microsporus produced a 1,3-1,4-β-D-glucan 4-glucanhydrolase (EC 3.2.1.73) which is able to hydrolyze β-D-glucan that contains both the 1,3- and 1,4-bonds (barley β-glucans). Its molecular mass was 33.7 kDa. Maximum activity was detected at pH values in the range of 4–5, and temperatures in the range of 50–60°C. The enzyme was able to reduce both the viscosity of the brewer mash and the filtration time, indicating its potential value for the brewing industry

Production and purification of influenza virus like particles using single-use technologies

There is an increasing trend in the biopharmaceutical market towards the implementation of single-use technologies (SUT) in bioprocesses. These technologies address the needs of bio therapeutic development and manufacturing with appealing advantages over the conventional systems. SUT can be operated at lower costs, eliminating the need for cleaning and regeneration of components, improving process-to-process turnaround, being more flexible enabling modular facilities, and easy to scale up. This work describes the up and downstream processing of Influenza Virus-like particles (VLPs), produced using the baculovirus expression system with High Five cells. The single-use Mobious ®Bioreactor is compared with a glass stirred tank in terms of growth kinetics, cell viability, stability and VLPs production, showing comparable results. The use of this single-use bioreactor was already reported by our group for the successful production of a hepatitis C VLP vaccine candidate. Moreover, we report on the development of a single-use platform process for purification of Influenza VLPs. We have undertaken an effort to replace chromatographic steps from our platform, with the ultimate goal of an all filtration purification process. The proposed process employs either normal or tangential flow filtration for the clarification stage, followed by a cascade of ultrafiltration steps with different pore sizes and a sterile filtration step to achieve the needed concentration and purity specifications. Efforts to clear nucleic acid without the use of an endonuclease digestion step and the impact on the downstream unitary operations will also be described. By optimizing the filtration mode of operation we were able to achieve product recoveries of 80%. Globally, we have about 1.8 log reduction value (LRV) of DNA and total protein removal and a baculovirus’ LRV of 4. Overall, using SUT across all biomanufacturing operations we are able to speed up the process, to improve the scale-up and to reduce costs due to the removal of chromatographic and cleaning and validation steps

Comparative recognition by human IgG antibodies of recombinant proteins representing three asexual erythrocytic stage vaccine candidates of Plasmodium vivax

In previous immuno-epidemiological studies of the naturally acquired antibody responses to merozoite surface protein-1 (MSP-1) of Plasmodium vivax, we had evidence that the responses to distinct erythrocytic stage antigens could be differentially regulated. The present study was designed to compare the antibody response to three asexual erythrocytic stage antigens vaccine candidates of P. vivax. Recombinant proteins representing the 19 kDa C-terminal region of MSP-1(PvMSP19), apical membrane antigen n-1 ectodomain (PvAMA-1), and the region II of duffy binding protein (PvDBP-RII) were compared in their ability to bind to IgG antibodies of serum samples collected from 220 individuals from the state of Pará, in the North of Brazil. During patent infection with P. vivax, the frequency of individuals with IgG antibodies to PvMSP1(19), PvAMA-1, and PvDBP-RII were 95, 72.7, and 44.5% respectively. Although the frequency of responders to PvDBP-RII was lower, this frequency increased in individuals following multiple malarial infections. Individually, the specific antibody levels did not decline significantly nine months after treatment, except to PvMSP1(19). Our results further confirm a complex regulation of the immune response to distinct blood stage antigens. The reason for that is presently unknown but it may contribute to the high risk of re-infection in individuals living in the endemic areas.Universidade de São Paulo Faculdade de Ciências Farmacêuticas Departamento de Análises Clínicas e ToxicológicasUniversidade Federal do Pará Centro de Ciências Biológicas Departamento de PatologiaInternational Centre for Genetic Engineering and Biotechnology Centro de Ciências Biológicas Malaria Research GroupUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de Microbiologia, Imunologia e ParasitologiaUNIFESP, EPM, Depto. de Microbiologia, Imunologia e ParasitologiaSciEL

Sustainability assessment of half-sandwich panels based on alkali-activated ceramic/slag wastes cement versus conventional building solutions

This study assessed the sustainability of two partition walls and intended to contribute to the Circular Economy in the construction sector. A life cycle approach and a multi-criteria decision support method were applied to know the environmental, functional, and economic performances of the production process of half-sandwich panels based on alkali-activated ceramic/slag waste cement, choosing as system boundary the method “cradle to gate”. The proposed building solutions differ from each other in the type of insulating material used, either extruded polystyrene foam (APXPS) or expanded cork agglomerate board (APICB). Besides, a comparative analysis of the developed building solutions versus three reference constructive solutions: i) a conventional heavyweight partition wall, ii) a lightweight gypsum wall panel, and iii) a conceptual lightweight sandwich membrane building solution was performed. Results showed that the two proposed half-sandwich wall panels (APXPS and APICB) resulted in the most sustainable alternatives, of which the APXPS obtained the best overall results since it combined the best environmental, functional, and economic behavior. Besides, the environmental contribution analysis determined that the greatest environmental burden to the Global Warming Potential (GWP), in the case of the APXPS was associated with the XPS (57%), being the alkali activator (23%) placed as the second major contributor. When the ICB was used as the insulation layer, the energy used (nearly 38%) and the sodium silicate (about 17%) were the larger contributors to CO2 emissions. It is worth mentioning that the use of ICB represented a negative contribution (of about −34%) to the GWP category.This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/ 04029/2020, and the research project “CirMat: CIRcular aggregates for sustainable road and building MATerials”(ref. 16_Call#2)is funded by Iceland, Liechtenstein and Norway through the EEA Grants and Norway Grants, operationalized by the Portuguese Office of the Secretary of State for the Environment. RENEw, POCI-01-0247-FEDER-033834, that was co-funded by Fundo Europeu de Desenvolvimento Regional (FEDER), with Programa Operacional da Competitividade e Internacionalizaçao ˜ do Portugal 2020 (COMPETE 2020) The authors acknowledge the support of the DST group construction company for funding the project Chair DST/IB-S: Smart Systems for Construction

A 3D KINEMATICAL ANALYSIS OF LONG JUMP IN THE “GOLD MEETING RIO OF ATHLETICS 2007”

This study was based on the 3D kinematical analysis of long jump in an official competition of the International Association of Athletics Federation. A six camera kinematical analysis system was used to reconstruct the 3D coordinates of eighteen points, modeling the athlete’s body with the follow segments: head, trunk, arms, forearms, thighs, calves and feet. Several performance variables concerning the center of mass trajectories and velocities were used to characterize and compare the individual jumps. Descriptive statistics was used to compare the results obtained with those found in the literature

Bioprocess integration for human mesenchymal stem cells: from up to downstream processing scale-up to cell proteome characterization

Human mesenchymal stem cells (hMSC) are relevant cell-based products for autologous and allogeneic therapies. To deliver the required cell numbers and doses to therapy, scaling up production and purification processes (at least to the liter-scale) while ensuring high purity, viability and maintaining cells’ critical quality attributes (CQA) and functionality is essential [1]. Therefore, the aim of this work was to prove scalability of an integrated streamlined bioprocess compatible with current good manufacturing practices (cGMP) comprised by cell expansion, harvesting and volume reduction unit operations using human mesenchymal stem cells (hMSC) isolated from bone marrow (BM-MSC) and adipose tissues (AT-MSC). BM-MSC and AT-MSC expansion and harvesting steps were scaled-up from spinner flasks to 2 L scale stirred tank single-use bioreactor using synthetic microcarriers and xeno-free medium, ensuring high cellular volumetric productivities (50 x 106 cell.L-1.day-1), expansion factors (14 - 16 fold) and cell recovery yields (80%). For the concentration step, flat sheet cassettes (FSC) and hollow fiber cartridges (HF) were compared showing a fairly linear scale-up, with a need to slightly decrease the permeate flux (30 - 50 LMH, respectively) to maximize cell recovery yield. Nonetheless, FSC allowed to recover 18% more cells after a volume reduction factor of 50. Overall, at the end of the entire bioprocess more than 65% of viable (\u3e 95%) hMSC could be recovered without compromising cell’s CQA of viability, identity and differentiation potential. “Omic” tools in combination with standard analytical assays allow for a better cell characterization, increasing product and process understanding [2] and are thus fundamental for process development. Thus, alongside the standard quality assays for evaluating hMSC’s CQA, a proteomics workflow based on mass spectrometry tools was established to characterize the impact of processing on hMSC’ CQA. Overall, through sensitivity, robustness and throughput, this type of workflow provided the identification of specific signatures of the final product. Therefore, it proves to be essential to understand the cells’ final quality as well as to evaluate the impact of manufacturing at different stages of processing. References: [1] Pattasseril J et al, BioProcess Int. 2013, 3, 38–46. [2] Campbell A et al, Stem Cells Transl. Med. 2015, 4, 1155–1163. The authors acknowledge UniMS – Mass Spectrometry Unit team (ITQB-NOVA/iBET, Oeiras, Portugal), iNOVA4Health Research Unit (LISBOA-01-0145-FEDER-007344), and Fundação para a Ciência e Tecnologia (FCT, Portugal) for funding the project CARDIOSTEM (MITP-TB/ECE/0013/2013), and the grants SFRH/BD/51940/2012 (MIT-Portugal), SFRH/BD/52302/2013, SFRH/BD/52481/2014, SFRH/BPD/86513/201

Photodeposition of silver on Zinc/Calcium ferrite nanoparticles: A contribution to efficient effluent remediation and catalyst reutilization

The efficient photodegradation of textile dyes is still a challenge, especially considering resistant azo dyes. In this work, zinc/calcium mixed ferrite nanoparticles prepared by the sol-gel method were coupled with silver by a photodeposition method to enhance the photocatalytic potency. The obtained zinc/calcium ferrites are mainly cubic-shaped nanoparticles sized 15 ± 2 nm determined from TEM and XRD and an optical bandgap of 1.6 eV. Magnetic measurements indicate a superparamagnetic behavior with saturation magnetizations of 44.22 emu/g and 27.97 emu/g, respectively, for Zn/Ca ferrite and Zn/Ca ferrite with photodeposited silver. The zinc/calcium ferrite nanoparticles with photodeposited silver showed efficient photodegradation of the textile azo dyes C.I. Reactive Blue 250 and C.I. Reactive Yellow 145. Subsequent cycles of the use of the photocatalyst indicate the possibility of magnetic recovery and reutilization without a significant loss of efficiency.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UIDB/04650/2020) and research project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020) funded by FCT, FEDER, PORTUGAL2020, and COMPETE2020

Engineering scalable manufacturing of high-quality human MSC for cell therapy: From up to downstream processing integration to cell proteome characterization

Human mesenchymal stem cells (hMSC) are relevant cell therapy products for autologous and allogeneic therapies. To deliver the required cell numbers and doses to therapy, scaling up production and purification processes (at least to the liter-scale) while ensuring high purity, viability and maintaining cells’ critical quality attributes (CQA) and functionality is essential. Therefore, the aim of this work was to prove scalability of an integrated streamlined bioprocess compatible with current good manufacturing practices (cGMP) comprised by cell expansion, harvesting, volume reduction and washing unit operations using human mesenchymal stem cells (hMSC) isolated from bone marrow (BM-MSC) and adipose tissues (AT-MSC). Single-use technologies were adopted at different steps of the manufacturing workflow to support process integration and scale-up. BM-MSC and AT-MSC expansion and harvesting steps were scaled-up from spinner flasks to 2 L single-use stirred tank bioreactor using synthetic microcarriers and xeno-free medium, ensuring high cellular volumetric productivities (50 x 106 cell.L-1.day-1), expansion factors (14 - 16 fold) and cell recovery yields (\u3e80%). For the volume reduction and washing steps, flat sheet cassettes (FSC) and hollow fiber cartridges (HF) were compared showing a fairly linear scale-up, with a need to slightly decrease the permeate flux (30 - 50 LMH, respectively) to maximize cell recovery yield. Nonetheless, FSC performed better allowing recovering 18% more cells after a volume reduction factor of 50 without compromising cell’s CQA of viability, identity and differentiation potential. “Omic” tools in combination with standard analytical assays allow for a better cell characterization, increasing product and process understanding and are thus fundamental for process development. Thus, alongside the standard quality assays for evaluating hMSC’s CQA, a proteomics workflow based on mass spectrometry tools was established to characterize the impact of processing on hMSC’ CQA. Overall, through sensitivity, robustness and throughput, this type of workflow provided the identification of specific signatures of the final product. Therefore, it proves to be essential to understand the cells’ final quality as well as to evaluate the impact of manufacturing at different stages of processing. The authors acknowledge UniMS – Mass Spectrometry Unit team (ITQB-NOVA/iBET, Oeiras, Portugal), iNOVA4Health Research Unit (LISBOA-01-0145-FEDER-007344), and Fundação para a Ciência e Tecnologia (FCT, Portugal) for funding the project CARDIOSTEM (MITP-TB/ECE/0013/2013), and the grants SFRH/BD/51940/2012 (MIT-Portugal), SFRH/BD/52302/2013, SFRH/BD/52481/2014, SFRH/BPD/86513/2012