Optoelectronic Instrument Monitors pH in a Culture Medium

An optoelectronic instrument monitors the pH of an aqueous cell-culture medium in a perfused rotating-wall-vessel bioreactor. The instrument is designed to satisfy the following requirements: It should be able to measure the pH of the medium continuously with an accuracy of 0.1 in the range from 6.5 to 7.5. It should be noninvasive. Any material in contact with the culture medium should be sterilizable as well as nontoxic to the cells to be grown in the medium. The biofilm that inevitably grows on any surface in contact with the medium should not affect the accuracy of the pH measurement. It should be possible to obtain accurate measurements after only one calibration performed prior to a bioreactor cell run. The instrument should be small and lightweight. The instrument includes a quartz cuvette through which the culture medium flows as it is circulated through the bioreactor. The cuvette is sandwiched between light source on one side and a photodetector on the other side. The light source comprises a red and a green light-emitting diode (LED) that are repeatedly flashed in alternation with a cycle time of 5 s. The responses of the photodiode to the green and red LEDs are processed electronically to obtain a quantity proportional to the ratio between the amounts of green and red light transmitted through the medium

Ethical issues associated with in-hospital emergency from the medical emergency team's perspective: a national survey

Medical Emergency Teams (METs) are frequently involved in ethical issues associated to in-hospital emergencies, like decisions about end-of-life care and intensive care unit (ICU) admission. MET involvement offers both advantages and disadvantages, especially when an immediate decision must be made. We performed a survey among Italian intensivists/anesthesiologists evaluating MET's perspective on the most relevant ethical aspects faced in daily practice

Rough-and-tumble play as a window on animal communication.

Rough-and-tumble play (RT) is a widespread phenomenon in mammals. Since it involves competition, whereby one animal attempts to gain advantage over another, RT runs the risk of escalation to serious fighting. Competition is typically curtailed by some degree of cooperation and different signals help negotiate potential mishaps during RT. This review provides a framework for such signals, showing that they range along two dimensions: one from signals borrowed from other functional contexts to those that are unique to play, and the other from purely emotional expressions to highly cognitive (intentional) constructions. Some animal taxa have exaggerated the emotional and cognitive interplay aspects of play signals, yielding admixtures of communication that have led to complex forms of RT. This complexity has been further exaggerated in some lineages by the development of specific novel gestures that can be used to negotiate playful mood and entice reluctant partners. Play-derived gestures may provide new mechanisms by which more sophisticated communication forms can evolve. Therefore, RT and playful communication provide a window into the study of social cognition, emotional regulation and the evolution of communication systems

When the individual comes into play: The role of self and the partner in the dyadic play fighting of rats

Social play in rats is rewarding and important for the development of brain and social skills. There are differences in the amount of play behavior displayed among individuals, with earlier studies suggesting that, despite variation across trials, individual differences tend to be consistent. In the present study, juvenile Lister-hooded rats were paired with a different, unfamiliar same-sex partner on three days and based on the amount of play each individual initiated, it was characterized as a high, medium or low player. Using this categorization, we explored three features related to individual differences. First, we show that by increasing the number of test days from two, as was done in a previous study (Lesscher et al., 2021), to three, characterization was effectively improved. Secondly, while the earlier study only used males, the present study showed that both sexes exhibit a similar pattern of individual differences in the degree of playfulness. Even though low players consistently initiated less play than medium and high players, all rats varied in how much play they initiated from one trial to the next. Thirdly, we assessed two potential mechanisms by which the playfulness of one rat can modify the level of playfulness of the other rat (i.e., emotional contagion vs homeostasis). Analyses of individuals' contribution to the play of dyads suggest that rats consistently adjust their play behavior depending on the behavior displayed by the partner. Since this adjustment can be positive or negative, our data support a homeostatic mechanism, whereby individuals increase or decrease the amount of play they initiate, which results in the experience of an overall stable pattern of play across trials. Future research will investigate the neural bases for individual differences in play and how rats maintain a preferred level of play

Enzymatic synthesis of lignin derivable pyridine based polyesters for the substitution of petroleum derived plastics

Following concerns over increasing global plastic pollution, interest in the production and characterization of bio-based and biodegradable alternatives is rising. In the present work, the synthesis of a series of fully bio-based alternatives based on 2,4-, 2,5-, and 2,6-pyridinedicarboxylic acid-derived polymers produced via enzymatic catalysis are reported. A similar series of aromatic-aliphatic polyesters based on diethyl-2,5-furandicarboxylate and of the petroleum-based diethyl terephthalate and diethyl isophthalate were also synthesized. Here we show that the enzymatic synthesis starting from 2,4-diethyl pyridinedicarboxylate leads to the best polymers in terms of molecular weights (M n = 14.3 and M w of 32.1 kDa when combined with 1,8-octanediol) when polymerized in diphenyl ether. Polymerization in solventless conditions were also successful leading to the synthesis of bio-based oligoesters that can be further functionalized. DSC analysis show a clear similarity in the thermal behavior between 2,4-diethyl pyridinedicarboxylate and diethyl isophthalate (amorphous polymers) and between 2,5-diethyl pyridinedicarboxylate and diethyl terephthalate (crystalline polymers)

Regulating Glucose and pH, and Monitoring Oxygen in a Bioreactor

A system that automatically regulates the concentration of glucose or pH in a liquid culture medium that is circulated through a rotating-wall perfused bioreactor is described. Another system monitors the concentration of oxygen in the culture medium

Basal Ganglia Involvement in the Playfulness of Juvenile Rats

Play is an important part of normal childhood development and can be readily studied in the laboratory rat in the form of rough‐and‐tumble play. Given the robust nature of rough‐and‐tumble play, it has often been assumed that the basal ganglia would have a prominent role in modulating this behavior. Recent work using c‐fos expression as a metabolic marker for neural activity combined with temporary inactivation of relevant corticostriatal regions and pharmacological manipulations of opioid, cannabinoid, and dopamine systems has led to a better understanding of how basal ganglia circuitry may be involved in modulating social play in the juvenile rat. Studies using selective play deprivation have also provided insight into the consequences of playful experiences on basal ganglia function. Data reviewed in this paper support a role for the basal ganglia in social play and also suggest that corticostriatal functioning also benefits from playful activities

Mechanistic investigation of the effect of endoglucanases related to pulp refining

Endoglucanases are increasingly being touted as the ultimate solution for reducing energy consumption during the refining process in the pulp and paper industry. However, due to the high variety of endoglucanases in different enzyme formulations, these perform heterogeneously when applied to different pulps. In this study, the effect of four endoglucanases on softwood and hardwood pulp was studied using confocal laser scanning microscopy (CLSM) after addition of fluorescently labelled carbohydrate binding modules (CBMs). Nuclear magnetic resonance (NMR) analysis and high-performance liquid chromatography quantification of released oligo- and monosaccharides was performed for in-depth mechanistical investigation. Changes in the crystallinity levels caused by enzymatic degradation of amorphous regions were monitored by incubation with two different CBMs from Caldicellulosiruptor bescii and from Thermobifida fusca with high preference to either amorphous or crystalline regions of cellulose, respectively. When dosed at identical activity on the endoglucanase specific CellG5 substrate, CLSM analysis indicated the highest decrease of amorphous regions for those endoglucanases which were also most active in laboratory refining trials and which released highest amounts of cellooligomers from pulp. Using 13C-NMR analysis, an increase in para-crystalline cellulose caused by enzyme application was observed. Release of reducing sugars was determined at identical CellG5 dosage, indicating a high variance between the enzymes, especially when complex enzyme formulations were used. Scanning electron microscopy images were obtained for visualization of the endoglucanase activity. The results of mechanistical studies indicate that reduction of amorphous moieties of pulp by endoglucanases is especially beneficial for the refining proces

Making sense of social pretense: The effect of the dyad, sex and language ability in a large observational study of children’s behaviors in a social pretend play context

Pretend play with peers is purportedly an important driver of social development in the preschool period, however, fundamental questions regarding the features of children’s pretend play with a peer, and the effect of the dyad for pretend play, have been overlooked. The current study undertook detailed behavioral coding of social pretend play in 134 pairs of 5-year-old children (54% boys) in order to address three main aims: (i) describe the duration and proportion of children engaging in key social pretend play behaviors, namely, calls for attention, negotiation (comprising role assignment and joint proposals) and enactment of pretend play, (ii) examine the effect of the dyad in influencing the occurrence of different social pretend play behaviors, and (iii) assess the independent and combined effect of individual child characteristics (i.e., language ability and sex) that may influence social pretend play behaviors beyond the influence of the dyad. Results demonstrated the overwhelming effect of the dyad in shaping children’s social pretend play behaviors, with language ability and sex explaining relatively little of the total variability in play behaviors. Results are discussed considering the contribution that this type of study can make to theories of associations between children’s social development and social pretend play.LEGO Foundatio