Serverless streaming for emerging media: towards 5G network-driven cost optimization

Multimedia Tools and Applications - Immersive 3D media is an emerging type of media that captures, encodes and reconstructs the 3D appearance of people and objects, with applications in...     

Monitoring the effect of high pressure and transglutaminase treatment of milk on the evolution of flavour compounds during lactic acid fermentation using PTR-ToF-MS

In this study, the effects of thermal or high hydrostatic pressure (HHP) treatment of a milk base in the absence or presence of a transglutaminase (TGase) protein cross-linking step on the flavour development of yoghurt were investigated. The presence of several tentatively identified volatile flavour compounds (VOCs), both during the enzymatic treatment and the lactic acid fermentation of the milk base, were monitored using a proton transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS). The formation of the major flavour compounds (acetaldehyde, diacetyl, acetoin, and 2-butanone) followed a sigmoidal trend described by the modified Gompertz model. The HHP treatment of milk increased significantly the volatile compound formation rate whereas it did not affect the duration of the lag phase of formation, with the exception of acetaldehyde and diacetyl formation. On the contrary, the TGase cross-linking of milk did not significantly modify the formation rate of the volatile compounds but shortened the duration of the lag phase of their formation.     

Principles and Current Clinical Landscape of Multispecific Antibodies against Cancer

Building upon the resounding therapeutic success of monoclonal antibodies, and supported by accelerating progress in engineering methods, the field of multispecific therapeutic antibodies is growing rapidly. Over 140 different molecules are currently in clinical testing, with excellent results in recent phase 1–3 clinical trials for several of them. Multivalent bispecific IgG-modified formats predominate today, with a clear tendency for more target antigens and further increased valency in newer constructs. The strategies to augment anticancer efficacy are currently equally divided between disruption of multiple surface antigens, and additional redirection of cytotoxic T or NK lymphocytes against the tumor. Both effects complement other modern modalities, such as tyrosine kinase inhibitors and adoptive cell therapies, with which multispecifics are increasingly applied in combination or merged, for example, in the form of antibody producing CAR-T cells and oncolytics. While mainly focused on B-cell malignancies early on, the contemporary multispecific antibody sector accommodates twice as many trials against solid compared to hematologic cancers. An exciting emerging prospect is the targeting of intracellular neoantigens using T-cell receptor (TCR) fusion proteins or TCR-mimic antibody fragments. Considering the fact that introduction of PD-(L)1 inhibitors only a few years ago has already facilitated 5-year survival rates of 30–50% for per se highly lethal neoplasms, such as metastatic melanoma and non-small-cell lung carcinoma, the upcoming enforcement of current treatments with “next-generation” immunotherapeutics, offers a justified hope for the cure of some advanced cancers in the near future.     

Development and Evaluation of a Continuous Ambient PM2.5 Mass Monitor

A Continuous Ambient Mass Monitor (CAMM) for fine particle mass (PM_2.5) has recently been developed at the Harvard School of Public Health. The principle of this method is based on the measurement of the increase in pressure drop across a membrane filter (Fluoropore^TM) during particle sampling. The monitor consists of a conventional impactor inlet to remove particles larger than 2.5 mu m, a diffusion dryer to remove particle-bound water, a filter tape to collect particles, a filter tape transportation system to allow unassisted sampling, and a data acquisition and control unit. For each sampling period (typically 30- 60 min), a new segment of the filter tape is exposed so that particles remain close to equilibrium with the sample air during their collection. This results in mini mization of volatilization and adsorption artifacts during sampling. Furthermore, since the required flow rate for the fine particle mass monitoring channel is only 0.3 L / min, the relative humidity of the air sample can be easily reduced to 40% or less using a NafionTM diffusion dryer to remove particle-bound water. The CAMM has a detection limit of > 5 mu g / m³ for PM_2.5 concentrations averaged over 1 h. The performance of the newly developed monitor was investigated through laboratory and field studies. Laboratory tests included a calibration of the CAMM using polystyrene latex (PSL) and silica particles. A series of field studies were conducted in 7 cities with presumably different PM_2.5 chemical composition. The 24 1-h CAMM measurements were averaged and compared to Harvard Impactor (HI) 24 h PM_2.5 integrated measurements. Based on 211 valid sampling days, the measurements obtained from the Harvard Impactor and the CAMM were highly correlated (r² = 0.90). The average CAMM-to-HI concentration ratio was 1.07 (+- 0.18).     

Performance Stability of the Harvard Ambient Particle Concentrator

The Harvard Ambient Particle Concentrator (HAPC) has been used routinely for exposure testing for a period of approximately three years. The stability of concentrator performance has been investigated as a function of local meteorological conditions, ambient particle concentrations, composition, and size distribution. Concentrator performance is characterized by the concentration enrichment factor (CEF), a ratio of concentrated particle mass (or sulfate) concentration to the ambient concentration. Over three years of normal operation, the mass and sulfate CEFs averaged 27.9 and 28.6, respectively. The majority of variability in the CEF was found to be related to the mass median aerodynamic diameter (MMAD) of ambient particles and to the HAPC's total operating pressure drop.

The 50% cutpoint of the HAPC is 0.15 μ m. Between 0.15 and 2.5 μ m, the HAPC concentrates ambient particle mass by approximately a factor of 28. It is logical that changes in particle CEF should be influenced by the amount of ambient particle mass within the concentrator's effective size range.

The concentrator operates optimally at a pressure drop of 2.5 in. of water per stage. Total pressure drop ranges from 7.5–25 in. of water, depending on the alignment of the slits of the virtual impactors and other parameters. Increases in the pressure drop result in decrease of the CEF, mainly due to excessive particle loss by impaction on the edges of the collection slit. In contrast, the minor operating pressure drop was found to be consistently lower on days where neither the ambient particle mass, temperature, or relative humidity were high. This subset of days was found to have a higher CEF than days where any of the three variables were high. The HAPC minor flow pressure drops are thus monitored carefully, since they are the most controllable indicator of concentration enrichment efficiency.     

Installation of PV systems in Greece—Reliability improvement in the transmission and distribution system

Photovoltaic (PV) power systems are becoming one of the most developing investment areas in the field of Renewable Energy Sources (RES). A statement of the status quo of PV power systems in Greece, and their contribution towards the improvement of power system reliability, is the scope of the present paper. Siting and installation of PV power systems is performed according to a recent Greek law, along with environmental and geographical constraints. Meteorological data are computed, formulated and imported to appropriate software in order to simulate the PV units and generate their power output. Data for unserved loads, resulting from load shedding during peak hours, are compared to the above estimated power production. Assuming that a proportion of the eventually unsupplied power could be provided by the accessed power generation of the PV units, the reliability of both transmission and distribution system is improved. The impact on the transmission system is shown by an improvement of LOLP and LOEP indices, whereas peak shaving for the Interconnected Greek Transmission System (IGTS) is also illustrated. For the distribution system the impact is quantified using the distribution system reliability indices SAIDI, SAIFI, and CAIDI. Finally, the resulting improvement is also expressed in financial terms.     

Generation of linalool derivatives in an artificial honey produced from bees fed with linalool-enriched sugar syrup

This paper presents a novel procedure to investigate the bioconversion of nectar components via the ‘intermediate’ honeybee and under the effect of the conditions in the beehive. The procedure was applied with linalool, the major component in the extract of Citrus spp. flowers, in order to investigate its bioconversion to linalool derivatives, the major volatiles of citrus honey. Bees were fed daily with 1 L sugar syrup 1:1 (w/v) containing 1 mL of (±) linalool, while control bees were fed with the same amount of linalool-free syrup. The artificial honey was analysed by means of ultrasound-assisted extraction followed by GC–MS analysis. The results show that the formation of both furan and pyran linalool oxides as well as terpendiol I is favoured, probably catalysed by the enzymes secreted by the bee. On the contrary, important linalool derivatives of citrus honey such as lilac aldehydes, cis- and trans-dehydroxy linalool oxides (E)-2,6-dimethyl-6-hydroxy-2,7-octadienal and (Z)-8-hydroxylinalool were absent in the artificial honey, suggesting the requirement of a plant-derived enzyme for their bioconversion. The same stands for (E)-8-hydroxylinalool, major volatile of citrus honey, although small amounts were present in the artificial honey. From these results, it can be concluded that feeding honeybees with linalool-enriched sugar syrup is not an effective way to produce artificial citrus honey similar to the natural one.     

Application of high-pressure treatment on ovine brined cheese: Effect on composition and microflora throughout ripening

Ovine brined cheese was high-pressure (HP) treated at 200 or 500 MPa for 15 min at 20 °C on the 15th day of ripening. Compared to control cheese, HP treatment did not affect significantly (P > 0.05) the pH values, moisture, fat in dry matter, protein in dry matter and salt in moisture contents of cheeses at 90 days. The counts of total aerobic mesophilic bacteria, thermophilic lactococci, thermophilic lactobacilli and non starter lactic acid bacteria (NSLAB) were not affected by HP treatment of cheese at 200 MPa throughout ripening. After 90 days of ripening, the same microbial groups in cheese treated at 500 MPa were about 1.2, 3.6, 2.1 and 4 log units lower than in control cheese respectively. Coliforms were reduced faster at non detectable levels in HP treated cheeses than in control cheese. Regarding the bacterial enzymatic activities in cheese, aminopeptidase activity (Apep) was marginally favoured by both HP treatments. However, its activity was decreased at 90 days due probably to loss in brine. In contrast, lactate dehydrogenase (LDH) activity, following the bacteria cell lysis, was negatively affected by HP treatment at 500 MPa throughout ripening.Industrial relevanceThe data obtained from this work suggest that application of HP treatment under optimized conditions on ovine cheese in brine can be used to reduce effectively the undesirable microbial load in it and to cause moderate enhancement of aminopeptidase activity, without modifying its composition.