Transient increases in intracellular calcium and reactive oxygen species levels in TCam-2 cells exposed to microgravity

The effects of microgravity on functions of the human body are well described, including alterations in the male and female reproductive systems. In the present study, TCam-2 cells, which are considered a good model of mitotically active male germ cells, were used to investigate intracellular signalling and cell metabolism during exposure to simulated microgravity, a condition that affects cell shape and cytoskeletal architecture. After a 24 hour exposure to simulated microgravity, TCam-2 cells showed 1) a decreased proliferation rate and a delay in cell cycle progression, 2) increased anaerobic metabolism accompanied by increased levels of intracellular Ca(2+), reactive oxygen species and superoxide anion and modifications in mitochondrial morphology. Interestingly, all these events were transient and were no longer evident after 48 hours of exposure. The presence of antioxidants prevented not only the effects described above but also the modifications in cytoskeletal architecture and the activation of the autophagy process induced by simulated microgravity. In conclusion, in the TCam-2 cell model, simulated microgravity activated the oxidative machinery, triggering transient macroscopic cell events, such as a reduction in the proliferation rate, changes in cytoskeleton-driven shape and autophagy activation

Managing rare and undetectable events in risk assessment: the case of a satellite system launch project

Assessing the wide diversity of risk types in large and complex projects using the traditional hyperbolic iso-risks curves may seem a simplistic and reductive approach, and evaluating the risk factor through the multiplication of likelihood and severity parameters results in defining as dangerous those risks that are associated either with rare but devastating consequences or with probable but minor effects. In this work, the authors aimed at focusing on those risks that, despite their low occurrence probability, may significantly compromise a project result. To this extent, a different formula has been used to compute the risk factor, keeping into account risk detectability and evaluating the potential consequences in four different domains (cost, time, performance, reputation). This approach has been validated on the case of a large industrial project related to the launch of an innovative mobile telecommunications system, collecting the experts' opinions in a primary Italian firm in aerospace industry

Storage Location Assignment Problem: implementation in a warehouse design optimization tool

This paper focuses on possible improvements of common practices of warehouse storage management taking cue from Operations Research SLAP (Storage Location Assignment Problem), thus aiming to reach an efficient and organized allocation of products to the warehouse slots. The implementation of a SLAP approach in a tool able to model multiple storage policies will be discussed, with the aim both to reduce the overall required warehouse space - to efficiently allocate produced goods - and to minimize the internal material handling times. The overcome of some of the limits of existing warehousing information management systems modules will be shown, sketching the design of a software tool able to return an organized slot-product allocation. The results of the validation of a prototype on an industrial case are presented, showing the efficiency increase of using the proposed approach with dedicated slot storage policy adoption

Integrating MRP in production systems simulation tools

Literature review suggests concentrating on the development of new reference model for manufacturing system simulation, which may implement an operation logic much closer to real industrial contexts. A production system modelling tool should be designed with the aim of standardizing and simplifying the simulation of manufacturing processes and to widespread this approach in SMEs. With this aim, the authors got committed in designing a reference model for providing a structural framework to support shop-floor simulation and optimization. This paper presents the basic framework logic and structure of the simulation tool, showing how it is possible to represent it in Business Process Modelling Notation (BPMN). On top of this, the efforts of implementing an MRP module on top of a simulation took which was originally conceived to embed look-back material handling policies area described, together with the operative solutions chosen to reach the integration

Storage Location Assignment Problem: implementation in a warehouse design optimization tool

This paper focuses on possible improvements of common practices of warehouse storage management taking cue from Operations Research SLAP (Storage Location Assignment Problem), thus aiming to reach an efficient and organized allocation of products to the warehouse slots. The implementation of a SLAP approach in a tool able to model multiple storage policies will be discussed, with the aim both to reduce the overall required warehouse space - to efficiently allocate produced goods - and to minimize the internal material handling times. The overcome of some of the limits of existing warehousing information management systems modules will be shown, sketching the design of a software tool able to return an organized slot-product allocation. The results of the validation of a prototype on an industrial case are presented, showing the efficiency increase of using the proposed approach with dedicated slot storage policy adoption

On tasks and soft skills in operations and supply chain management: analysis and evidence from the O*NET database

Purpose: The purpose of the study is to identify the soft skills and abilities that are crucial to success in the fields of operations management (OM) and supply chain management (SCM), using the ONET database and the classification of a set of professional figures integrating values for task skills and abilities needed to operate successfully in these professions. Design/methodology/approach: The study used the ONET database to identify the soft skills and abilities required for success in OM and SCM industries. Correlation analysis was conducted to determine the tasks required for the job roles and their characteristics in terms of abilities and soft skills. ANOVA analysis was used to validate the findings. The study aims to help companies define specific assessments and tests for OM and SCM roles to measure individual attitudes and correlate them with the job position. Findings: As a result of the work, a set of soft skills and abilities was defined that allow, through correlation analysis, to explain a large number of activities required to work in the operations and SCM (OSCM) environment. Research limitations/implications: The work is inherently affected by the database used for the professional figures mapped and the scores that are attributed within ONET to the analyzed elements. Practical implications: The information resulting from this study can help companies develop specific assessments and tests for the roles of OM and SCM to measure individual attitudes and correlate them with the requirements of the job position. The study aims to address the need to identify soft skills in the human sphere and determine which of them have the most significant impact on the OM and SCM professions. Originality/value: The originality of this study lies in its approach to identify the set of soft skills and abilities that determine success in the OM and SCM industries. The study used the ONET database to correlate the tasks required for specific job roles with their corresponding soft skills and abilities. Furthermore, the study used ANOVA analysis to validate the findings in other sectors mapped by the same database. The identified soft skills and abilities can help companies develop specific assessments and tests for OM and SCM roles to measure individual attitudes and correlate them with the requirements of the job position. In addressing the necessity for enhanced clarity in the domain of human factor, this study contributes to identifying key success factors. Subsequent research can further investigate their practical application within companies to formulate targeted growth strategies and make appropriate resource selections for vacant positions

Microbioreactor (micro-Matrix) potential in aerobic and anaerobic conditions with different industrially relevant microbial strains

Microscale fermentation systems are important high throughput tools in clone selection, and bioprocess set up and optimization, since they provide several parallel experiments in controlled conditions of pH, temperature, agitation, and gas flow rate. In this work we evaluated the performance of biotechnologically relevant strains with different respiratory requirements in the micro-Matrix microbioreactor. In particular Escherichia coli K4 requires well aerated fermentation conditions to improve its native production of chondroitin-like capsular polysaccharide, a biomedically attractive polymer. Results from batch and fed-batch experiments demonstrated high reproducibility with those obtained on 2 L reactors, although highlighting a pronounced volume loss for longer-term experiments. Basfia succiniciproducens and Actinobacillus succinogenes need CO2 addition for the production of succinic acid, a building block with several industrial applications. Different CO2 supply modes were tested for the two strains in 24 h batch experiments and results well compared with those obtained on lab-scale bioreactors. Overall, it was demonstrated that the micro-Matrix is a useful scale-down tool that is suitable for growing metabolically different strains in simple batch process, however, a series of issues should still be addressed in order to fully exploit its potential

Hyaluronan Hydrogels: Rheology and Stability in Relation to the Type/Level of Biopolymer Chemical Modification

BDDE (1,4-butanediol-diglycidylether)-crosslinked hyaluronan (HA) hydrogels are widely used for dermo-aesthetic purposes. The rheology and stability of the gels under physiological conditions greatly affect their clinical indications and outcomes. To date, no studies investigating how these features are related to the chemistry of the polymeric network have been reported. Here, four available HA-BDDE hydrogels were studied to determine how and to what extent their rheology and stability with respect to enzymatic hydrolysis relate to the type and degree of HA structural modification.1 H-/13 C-NMR analyses were associated for the quantification of the “true” HA chemical derivatization level, discriminating between HA that was effectively crosslinked by BDDE, and branched HA with BDDE that was anchored on one side. The rheology was measured conventionally and during hydration in a physiological medium. Sensitivity to bovine testicular hyaluronidase was quantified. The correlation between NMR data and gel rheology/stability was evaluated. The study indicated that (1) the gels greatly differed in the amounts of branched, crosslinked, and overall modified HA, with most of the HA being branched; (2) unexpectedly, the conventionally measured rheological properties did not correlate with the chemical data; (3) the gels’ ranking in terms of rheology was greatly affected by hydration; (4) the rheology of the hydrated gels was quantitatively correlated with the amount of crosslinked HA, whereas the correlations with the total HA modification level and with the degree of branched HA were less significant; (5) increasing HA derivatization/crosslinking over 9/3 mol% did not enhance the stability with respect to hyaluronidases. These results broaden our knowledge of these gels and provide valuable information for improving their design and characterization

VOF Simulation of The Cavitating Flow in High Pressure GDI Injectors

The paper describes the development in the OpenFOAM ® technology of a dynamic multiphase Volume-of-Fluid (VoF) solver, supporting mesh handling with topological changes, that has been used for the study of the physics of the primary jet breakup and of the flow disturbance induced by the nozzle geometry during the injector opening event in high-pressure Gasoline Direct Injection (GDI) engines. Turbulence modeling based on a scale-resolving approach has been applied, while phase change of fuel is accounted by means of a cavitation model that has been coupled with the VOF solver. Simulations have been carried out on a 6-hole prototype injector, especially developed for investigations in the framework of the collaborative project FUI MAGIE and provided by Continental Automotive SAS. Special attention has been paid to the domain decomposition strategy and to the code development of the solver, to ensure good load balancing and to minimize inter-processor communication, to achieve good performance and also high scalability on large computing clusters

Southwest Pacific subtropics responded to last deglacial warming with changes in shallow water sources

Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 29 (2014): 595–611, doi:10.1002/2013PA002584.This study examined sources of mixed layer and shallow subsurface waters in the subtropical Bay of Plenty, New Zealand, across the last deglaciation (~30–5 ka). δ18O and δ13C from planktonic foraminifera Globgerinoides bulloides and Globorotalia inflata in four sediment cores were used to reconstruct surface mixed layer thickness, δ18O of seawater (δ18OSW) and differentiate between high- and low-latitude water provenance. During the last glaciation, depleted planktonic δ18OSW and enriched δ13C (−0.4–0.1‰) indicate surface waters had Southern Ocean sources. A rapid δ13C depletion of ~1‰ in G. bulloides between 20 and 19 ka indicates an early, permanent shift in source to a more distal tropical component, likely with an equatorial Pacific contribution that persisted into the Holocene. At 18 ka, a smaller but similar shift in G. inflata δ13C depletion of ~0.3‰ suggests that deeper subsurface waters had a delayed reaction to changing conditions during the deglaciation. This contrasts with the isotopic records from nearby Hawke Bay, to the east of the North Island of New Zealand, which exhibited several changes in thermocline depth indicating switches between distal subtropical and proximal subantarctic influences during the early deglaciation ending only after the Antarctic Cold Reversal. Our results identify the midlatitude subtropics, such as the area around the North Island of New Zealand, as a key region to decipher high- versus low-latitude influences in Southern Hemisphere shallow water masses.Funding for this project came from NSF OCE-0823487 and 0823549-03.2014-12-1