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Background: Chlamydomonas reinhardtii is gaining recognition as a promising expression system for the production of recombinant proteins. However, its performance as a cellular biofactory remains suboptimal, especially with respect to consistent expression of heterologous genes. Gene silencing mechanisms, position effect, and low nuclear transgene expression are major drawbacks for recombinant protein production in this model system. To unveil the molecular changes following transgene insertion, retention, and expression in this species, we genetically engineered C. reinhardtii wild type strain 137c (strain cc-125 mt+) to express the fluorescent protein mVenus and subsequently analysed its intracellular proteome. Results: The obtained transgenic cell lines showed differences in abundance in more than 400 proteins, with multiple pathways altered post-transformation. Proteins involved in chromatin remodelling, translation initiation and elongation, and protein quality control and transport were found in lower abundance. On the other hand, ribosomal proteins showed higher abundance, a signal of ribosomal stress response. Conclusions: These results provide new insights into the modifications of C. reinhardtii proteome after transformation, highlighting possible pathways involved in gene silencing. Moreover, this study identifies multiple protein targets for future genetic engineering approaches to improve the prospective use of C. reinhardtii as cell biofactory for industrial applications. [ABSTRACT FROM AUTHOR]

Background: Chlamydomonas reinhardtii is gaining recognition as a promising expression system for the production of recombinant proteins. However, its performance as a cellular biofactory remains suboptimal, especially with respect to consistent expression of heterologous genes. Gene silencing mechanisms, position effect, and low nuclear transgene expression are major drawbacks for recombinant protein production in this model system. To unveil the molecular changes following transgene insertion, retention, and expression in this species, we genetically engineered C. reinhardtii wild type strain 137c (strain cc-125 mt+) to express the fluorescent protein mVenus and subsequently analysed its intracellular proteome. Results: The obtained transgenic cell lines showed differences in abundance in more than 400 proteins, with multiple pathways altered post-transformation. Proteins involved in chromatin remodelling, translation initiation and elongation, and protein quality control and transport were found in lower abundance. On the other hand, ribosomal proteins showed higher abundance, a signal of ribosomal stress response. Conclusions: These results provide new insights into the modifications of C. reinhardtii proteome after transformation, highlighting possible pathways involved in gene silencing. Moreover, this study identifies multiple protein targets for future genetic engineering approaches to improve the prospective use of C. reinhardtii as cell biofactory for industrial applications. [ABSTRACT FROM AUTHOR]

In the United States, after age 65, households face income and health risks, and a large fraction of these risks are transitory. While consumption significantly responds to transitory income shocks, out-of-pocket medical expenses do not. In contrast, both consumption and out-of-pocket medical expenses respond to transitory health shocks. Thus, most US elderly keep their out-of-pocket medical expenses close to a satiation point that varies with health. Consumption responds to health shocks mostly because adverse health shocks reduce the marginal utility of consumption. The effect of health on marginal utility changes the optimal transfers due to health shocks. (JEL D12, E21, G22, G51, I10, J14, J26) [ABSTRACT FROM AUTHOR]

SUMMARY: Diatoms are photosynthetic unicellular microalgae that drive global ecological phenomena in the biosphere and are emerging as sustainable feedstock for an increasing number of industrial applications. Diatoms exhibit enormous taxonomic and genetic diversity, which often results in peculiar biochemical and biological traits. Transposable elements (TEs) represent a substantial portion of diatom genomes and have been hypothesized to exert a relevant role in enriching genetic diversity and making a core contribution to genome evolution. Here, through long‐read whole‐genome sequencing, we identified a mutator‐like element (MULE) in the model diatom Phaeodactylum tricornutum, and we report the direct observation of its mobilization within the course of a single laboratory experiment. Under selective conditions, this TE inactivated the uridine monophosphate synthase (UMPS) gene of P. tricornutum, one of the few endogenous genetic loci currently targeted for selectable auxotrophy for functional genetics and genome‐editing applications. We report the observation of a recently mobilized transposon in diatoms with unique features. These include the combined presence of a MULE transposase with zinc‐finger SWIM‐type domains and a diatom‐specific E3 ubiquitin ligase of the zinc‐finger UBR type, which are suggestive of a mobilization mechanism. Our findings provide new elements for the understanding of the role of TEs in diatom genome evolution and in the enrichment of intraspecific genetic variability. Significance Statement: We identified a DNA transposon in the diatom Phaeodactylum tricornutum. This mutator‐like element encodes a transposase and a diatom‐specific E3 ubiquitin ligase, suggestive of a mobilization mechanism. We documented independent insertions that spontaneously inactivated the uridine monophosphate synthase (UMPS) locus, a common selectable marker. We provide insights on the role of transposons in diatom genome dynamics and evolution, and on the potential challenges of choosing UMPS as a selection locus in diatoms. [ABSTRACT FROM AUTHOR]

Vehicle integrated photovoltaics (VIPV) are among the identified solutions to reduce the environmental impacts of the transport sector. The model developed here simulates the VIPV system. It considers various usage patterns and vehicle types, several characteristics of the photovoltaic system and all the losses that may decrease energy yield. Focusing on a passenger car, simulations indicate the order of influence of the parameters on the outputs of the model: geographic locality, shading, thresholds due to extra-consumption needed to charge the vehicle's battery from the photovoltaic (PV) system and occurrence of recharge with the grid. With technology projections for 2030, with 30% shading, VIPV will cover a distance of up to 1444 km per year. This represents up to 12% of the driven mileage. For the best month, it can reach up to 14 km/day. For average Europe and realistic conditions, VIPV cover 648 km per year. Life cycle assessment (LCA) of a solarized passenger car shows a negative balance for a low-carbon electricity mix and average solar irradiance. In favorable conditions, the carbon footprint is up to 489 kg of CO2-equivalent avoided emissions on a 13-year lifespan. Beyond the focus on km and LCA, VIPV may provide useful functions in non-interconnected zones and for resilience in disaster areas. [ABSTRACT FROM AUTHOR]

The green microalga Chlamydomonas reinhardtii is emerging as a promising cell biofactory for secreted recombinant protein (RP) production. In recent years, the generation of the broadly used cell wall–deficient mutant strain UVM4 has allowed for a drastic increase in secreted RP yields. However, purification of secreted RPs from the extracellular space of C. reinhardtii strain UVM4 is challenging. Previous studies suggest that secreted RPs are trapped in a matrix of cell wall protein aggregates populating the secretome of strain UVM4, making it difficult to isolate and purify the RPs. To better understand the nature and behaviour of these extracellular protein aggregates, we analysed and compared the extracellular proteome of the strain UVM4 to its cell-walled ancestor, C. reinhardtii strain 137c. When grown under the same conditions, strain UVM4 produced a unique extracellular proteomic profile, including a higher abundance of secreted cell wall glycoproteins. Further characterization of high molecular weight extracellular protein aggregates in strain UVM4 revealed that they are largely comprised of pherophorins, a specific class of cell wall glycoproteins. Our results offer important new insights into the extracellular space of strain UVM4, including strain-specific secreted cell wall proteins and the composition of the aggregates possibly related to impaired RP purification. The discovery of pherophorins as a major component of extracellular protein aggregates will inform future strategies to remove or prevent aggregate formation, enhance purification of secreted RPs, and improve yields of recombinant biopharmaceuticals in this emerging cell biofactory. Key points: • Extracellular protein aggregates hinder purification of recombinant proteins in C. reinhardtii • Unassembled cell wall pherophorins are major components of extracellular protein aggregates • Known aggregate composition informs future strategies for recombinant protein purification [ABSTRACT FROM AUTHOR]

This work is devoted to the modeling and structural analysis of ventilation networks in small-scale mines using a physically oriented modeling method that ensures power conservation. Small-scale mines are common in the mineral extraction industry of underdeveloped countries and their physical characteristics are taken into account in the modeling process. The geometrical topology of the ventilation network in addition with the conservation laws of the fluid distribution along the network are considered in order to obtain a simple modeling methodology. Non-linear characteristics of the interconnected fluid dynamics represent a challenge to determine significant features of the system from a control point of view. Observability and controllability properties are analyzed by considering the structural systems approach. An structural analysis provides information based on the network topology independently of the mine parameters allowing the number of sensors and actuators to be reduced while also preserving the observability and controllability of the ventilation system. Experimental results are provided by building a small-scale ventilation network benchmark to evaluate the proposed model and its properties. [ABSTRACT FROM AUTHOR]

On-board photovoltaic (PV) energy generation is starting to be deployed in a variety of vehicles while still discussing its benefits. Integration requirements vary greatly for the different vehicles. Numerous types of PV cells and modules technologies are ready or under development to meet the challenges of this demanding sector. A comprehensive review of fast-changing vehicle-integrated photovoltaic (VIPV) products and lightweight PV cell and module technologies adapted for integration into electric vehicles (EVs) is presented in this paper. The number of VIPV projects and/or products is on a steady rise, especially car-based PV integration. Our analysis differentiates projects according to their development stage and technical solutions. The advantages and drawbacks of various PV cell and module technologies are discussed, in addition to recommendations for wide-scale deployment of the technologies. [ABSTRACT FROM AUTHOR]

Mankind has recognized the value of land plants as renewable sources of food, medicine, and materials for millennia. Throughout human history, agricultural methods were continuously modified and improved to meet the changing needs of civilization. Today, our rapidly growing population requires further innovation to address the practical limitations and serious environmental concerns associated with current industrial and agricultural practices. Microalgae are a diverse group of unicellular photosynthetic organisms that are emerging as next-generation resources with the potential to address urgent industrial and agricultural demands. The extensive biological diversity of algae can be leveraged to produce a wealth of valuable bioproducts, either naturally or via genetic manipulation. Microalgae additionally possess a set of intrinsic advantages, such as low production costs, no requirement for arable land, and the capacity to grow rapidly in both large-scale outdoor systems and scalable, fully contained photobioreactors. Here, we review technical advancements, novel fields of application, and products in the field of algal biotechnology to illustrate how algae could present high-tech, low-cost, and environmentally friendly solutions to many current and future needs of our society. We discuss how emerging technologies such as synthetic biology, high-throughput phenomics, and the application of internet of things (IoT) automation to algal manufacturing technology can advance the understanding of algal biology and, ultimately, drive the establishment of an algal-based bioeconomy. [ABSTRACT FROM AUTHOR]

Conventional microbial fuel cells (MFCs) consist of biological anodes and abiotic cathodes separated by a proton-exchange membrane. The abiotic cathode usually catalyses the reduction of oxygen to produce water by means of expensive catalysts such as platinum.1The cathodic reaction is often limiting in MFCs and researchers are now focusing on efficient, low-cost catalysts to improve oxygen reduction at the cathode. This paper describes a photosynthetic biocathode in a sediment-type MFC constructed without a proton-exchange membrane. The carbon and stainless steel cathode did not contain any catalyst, but was covered in a biofilm composed of a complex community including microalgae and cyanobacteria. Although electroactive species were detected in the cathode biofilm, no biocatalysis of oxygen reduction was observed. Enhancement of the current output was mostly due to the production of pure oxygen near the cathode surface by the photosynthetic biofilm. Photosynthesis could produce dissolved oxygen levels approximately four times higher than oxygen levels obtained by aeration. The MFC was able to generate a maximum power density of 11 mW/m2(projected anode area) over six months without feeding. [ABSTRACT FROM AUTHOR]

In this paper we consider linear structured systems which represent a large class of parameter-dependent linear systems and we study invariants for such systems under a large group of transformations including state feedback. In this context we consider the dimension of the maximal output-nulling invariant subspace of a linear structured system, the number and structure of its invariant zeros and its structure at infinity. We give generic characterizations of the invariants in terms of properties of the directed graph that can be naturally associated with a linear structured system. [ABSTRACT FROM AUTHOR]

In this paper we consider phase-type distributions. These distributions correspond to the random hitting time of an absorbing Markov chain. They are used for modelling various random times, in particular, those which appear in manufacturing systems as processing times, times to failure, repair times, etc. The Markovian nature of these distributions allows the use of very efficient matrix based computer methods for performance evaluation. In this paper we give a system theory oriented introduction to phase-type distributions. We concentrate mainly on the representation problem which consists of finding a Markov chain associated with some phase-type distribution. This is a realization problem in the sense of system theory with a lot of links with the classical linear system theory but also with a number of constraints which make the problem harder but more interesting. Indeed this problem has strong connections with the positive realization problem in control theory. The paper recalls known results, gives some new results, and points out the main remaining problems. [ABSTRACT FROM AUTHOR]

Introduces the notion of structured phase-type representations. Definition of a generic property for structured phase-type representations; Proof that an irreducible structured representation of a given order corresponds to a distribution whose degree is equal to the order; Discussion on the study of generic simplicity.

In this paper, linear structured systems with delays are defined and a simple graph representation for these systems is given. Then, the generic controllability of time-delay systems is introduced and a graph criterion for controllability is provided. The generic row-by-row decoupling problem without prediction of such systems is then studied and graphical necessary and sufficient solvability conditions for this problem is derived. [ABSTRACT FROM AUTHOR]

In this paper, it is shown that a static state feedback control law rejects the disturbance and simultaneously performs input-output decoupling, while ensuring internal stability of the closed loop system, if and only if an integer equality holds for the global undisturbed system and the row subsystems of the combined plant (where the disturbance is handled as a control input), namely in terms of their respective total contents (sums of the orders of the multiplicities of its infinite and finite unstable invariant zeros). [ABSTRACT FROM AUTHOR]

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The purpose of this paper is to propose an analytical method for the performance evaluation of closed-loop production lines with unreliable machines and finite buffers. Such a system consists of a set of K machines separated by buffers of finite capacity. There is a fixed number of pallets circulating in the closed loop. We assume that machines have deterministic processing times but are subject to failures. Failures and repair times are exponentially distributed. We approximate the behavior of this system by a continuous flow model. The continuous flow model is then analyzed with a decomposition technique, which is similar to that used for (open) production lines. Numerical experiments are reported that show that the results provided by this method are in general fairly accurate. [ABSTRACT FROM AUTHOR]

We consider transfer lines without buffer storage in between the machines and with synchronous transfer. The processing time of each machine is a constant but machines are unreliable. Our analysis is based on the overall completion time of the transfer line, which is the time between successive transfers of parts within the line. Two techniques are presented. The first one provides lower and upper bounds on the production rate. These bounds can be made as tight as desired. The second technique provides an approximation of the production rate. It is based on the approximation of some distributions by simpler distributions having the same mean and coefficient of variation. We first consider the case of transfer lines with identical processing times and exponential times to failure and times to repair. Extensions to different processing times and general repair times are also discussed. [ABSTRACT FROM AUTHOR]