Models of Protocells Undergoing Asymmetrical Division

The conditions that allow for the sustained growth of a protocell population are investigated in the case of asymmetrical division. The results are compared to those of previous studies concerning models of symmetrical division, where synchronization (between duplication of the genetic material and fission of the lipid container) was found under a variety of different assumptions about the kinetic equations and about the place where molecular replication takes place. Such synchronization allows a sustained proliferation of the protocell population. In the asymmetrical case, there can be no true synchronization, since the time to duplication may depend upon the initial size, but we introduce a notion of homogeneous growth that actually allows for the sustained reproduction of a population of protocells. We first analyze Surface Reaction Models, defined in the text, and we show that in many cases they undergo homogeneous growth under the same kinetic laws that lead to synchronization in the symmetrical case. This is the case also for Internal Reaction Models (IRMs), which, however, require a deeper understanding of what homogeneous growth actually means, as discussed below.

Comparing stigma between French people experiencing schizophrenia versus bipolar disorders

BACKGROUND

Among the multiple challenges that people experiencing mental illness in general, and schizophrenia or bipolar disorders in particular, have to face, stigma appears to be one of the most difficult to tackle. In France, the body of research about stigma regarding people experiencing schizophrenia or bipolar disorders is growing, but not as much as in other western countries.

AIMS

In this context, our study aims to explore and compare stigma in French people experiencing schizophrenia or bipolar disorders, along with their respective mental healthcare system experience, in order to better address them within public health policies.

METHODS

20 French mental health service users experiencing schizophrenia and 20 experiencing bipolar disorders answered the Stigma Scale, which assesses three dimensions of stigma (discrimination, difficulties of divulgation and lack of positive aspects). A semi-structured interview was used to collect information about the experience of the mental healthcare system (level of information, access to diagnosis, treatment, access to psychoeducation, etc.).

RESULTS

People experiencing schizophrenia and people experiencing bipolar disorders are different populations in terms of social impairment. However, they share a comparable negative experience of the mental healthcare system and a comparable level of information about their illness, to the exception of diagnosis divulgation, as people experiencing bipolar disorders have a better access to their diagnosis. People experiencing schizophrenia perceive a higher actual discrimination than people experiencing bipolar disorders.

CONCLUSIONS

Public health policies should take into account the strong perception of actual discrimination of people experiencing schizophrenia, with capitalizing on what seems beneficial for people experiencing bipolar disorders.

Serum HMGB1 levels are independently associated with glucose clamp-derived measures of insulin resistance in women with PCOS

PURPOSE

PCOS is associated with low grade inflammation which could play a role in insulin resistance and ovarian dysfunction. Preliminary findings suggested that serum levels of HMGB1, a cytokine involved in inflammation, might be altered in women with PCOS. Primary aim of this study was to assess whether HMGB1 serum concentrations are associated with PCOS and with the state of insulin resistance of these women.

METHODS

Sixty women with PCOS, selected to have a similar proportion of subjects with altered or normal insulin sensitivity, and 29 healthy controls were studied. Serum HMGB1 levels were compared in subgroups of PCOS women and controls. In PCOS women, insulin sensitivity was assessed by the glucose clamp technique and HMGB1 was measured at baseline and after acute hyperinsulinemia.

RESULTS

HMGB1 levels were similar in women with PCOS and controls and no elements used for diagnosing PCOS were associated with serum HMGB1. However, HMGB1 concentrations were higher in insulin-resistant vs insulin-sensitive PCOS women (p = 0.017), and inversely associated with insulin-induced total and non-oxidative glucose metabolism. In both subgroups of PCOS women, serum HMBG1 levels significantly increased after acute hyperinsulinemia.

CONCLUSIONS

These data suggest that HMGB1 levels are not associated with PCOS per se, but with insulin resistance. Further research should establish the underlying nature of this relationship, and whether this protein might play a role in the metabolic complications of PCOS.

Comparison of effect of CdS QD and ZnS QD and their corresponding salts on growth, chlorophyll content and antioxidative capacity of tomato

When applied in the same concentration to tomato plants, cadmium sulfate (CdSO4) and zinc sulfate (ZnSO4) were transported from soil to roots and from roots to shoots more readily than their nano counterparts: cadmium sulfide quantum dots (CdS QD) and zinc sulfide quantum dots (ZnS QD). Compared to the CdS QD, he higher rate of transport of CdSO4 resulted in a greater negative effect on growth, chlorophyll content, antioxidant properties, lipid peroxidation and activation of antioxidant defence systems. Although ZnSO4 was transported more rapidly than ZnS QD, the overall effect of Zn addition was positive (increase in total plant mass, stem length, antioxidant content and decrease in lipid peroxidation). However, these effects were more pronounced in the case of ZnS QD, suggesting that the mechanisms underpinning the activity of ZnS QD and ZnSO4 were different. Thus, the risk of phytotoxicity and food chain transfer of the two elements depended on their form (salt or nanoform), and consequently their effects on plants' growth and physiology were different.

Cadmium Sulfide Quantum Dots, Mitochondrial Function and Environmental Stress: A Mechanistic Reconstruction through In Vivo Cellular Approaches in Saccharomyces cerevisiae

Research on the effects of engineered nanomaterials (ENMs) on mitochondria, which represent one of the main actors in cell function, highlighted effects on ROS production, gametogenesis and organellar genome replication. Specifically, the mitochondrial effects of cadmium sulfide quantum dots (CdS QDs) exposure can be observed through the variation in enzymatic kinetics at the level of the respiratory chain and also by analyzing modifications of reagent and products in term of the bonds created and disrupted during the reactions through Fourier-transform infrared spectroscopy (FTIR). This study investigated both in intact cells and in isolated mitochondria to observe the response to CdS QDs treatment at the level of electron transport chain in the wild-type yeast Saccharomyces cerevisiae and in the deletion mutant Δtom5, whose function is implicated in nucleo-mitochondrial protein trafficking. The changes observed in wild type and Δtom5 strains in terms of an increase or decrease in enzymatic activity (ranging between 1 and 2 folds) also differed according to the genetic background of the strains and the respiratory chain functionality during the CdS QDs treatment performed. Results were confirmed by FTIR, where a clear difference between the QD effects in the wild type and in the mutant strain, Δtom5, was observed. The utilization of these genetic and biochemical approaches is instrumental to clarify the mitochondrial mechanisms implicated in response to these types of ENMs and to the stress response that follows the exposure.

The physiological sonographic features of the ovary in healthy subjects: a joint systematic review and meta-analysis by the Italian Society of Gynecology and Obstetrics (SIGO) and the Italian Society of Endocrinology (SIE)

PURPOSE

There is a lack of uniformity in the definition of normal ovary ultrasound parameters. Our aim was to summarize and meta-analyze the evidence on the topic. Full-text English articles published through December 31, 2020 were retrieved via MEDLINE and Embase. Data available for meta-analysis included: ovarian follicular count, ovarian volume, and ovarian Pulsatility Index (PI) assessed by Doppler ultrasound.

METHODS

Cohort, cross-sectional, prospective studies with a single or double arm were considered eligible. Interventional studies were included when providing baseline data. Both studies on pre- and post-menopausal women were screened; however, data on menopausal women were not sufficient to perform a meta-analysis. Studies on pre-pubertal girls were considered separately. Eighty-one papers were included in the meta-analysis.

RESULTS

The mean ovarian volume was 6.11 [5.81-6.42] ml in healthy women in reproductive age (5.81-6.42) and 1.67 ml [1.02-2.32] in pre-pubertal girls. In reproductive age, the mean follicular count was 8.04 [7.26-8.82] when calculated in the whole ovary and 5.88 [5.20-6.56] in an ovarian section, and the mean ovarian PI was 1.86 [1.35-2.37]. Age and the frequency of the transducers partly modulated these values. In particular, the 25-30-year group showed the higher mean follicular count (9.27 [7.71-10.82]), followed by a progressive age-related reduction (5.67 [2.23-9.12] in fertile women > 35 years). A significant difference in follicular count was also found according to the transducer's upper MHz limit.

CONCLUSION

Our findings provide a significant input to improve the interpretation and diagnostic accuracy of ovarian ultrasound parameters in different physiological and pathological settings.

Super-Exponential Growth in Models of a Binary String World

The Theory of the Adjacent Possible (TAP) equation has been proposed as an appropriate description of super-exponential growth phenomena, where a phase of slow growth is followed by a rapid increase, leading to a "hockey stick" curve. This equation, initially conceived to describe the growth in time of the number of new types of artifacts, has also been applied to several natural phenomena. A possible drawback is that it may overestimate the number of new artifact types, since it does not take into account the fact that interactions, among existing types, may produce types which have already been previously discovered. We introduce here a Binary String World (BSW) where new string types can be generated by interactions among (at most two) already existing types. We introduce a continuous limit of the TAP equation for the BSW; we solve it analytically and show that it leads to divergence in finite time. We also introduce a criterion to distinguish this type of behavior from the familiar exponential growth, which diverges only as t → ∝. In the BSW, it is possible to directly model the generation of new types, and to check whether the newborns are actually novel types, thus discarding the rediscoveries of already existing types. We show that the type of growth is still TAP-like, rather than exponential, although of course in simulations one never can observes true divergence. We also show that this property is robust with respect to some changes in the model, as long as it deals with types (and not with individuals).

Serum Mass Spectrometry Proteomics and Protein Set Identification in Response to FOLFOX-4 in Drug-Resistant Ovarian Carcinoma

Ovarian cancer is a highly lethal gynecological malignancy. Drug resistance rapidly occurs, and different therapeutic approaches are needed. So far, no biomarkers have been discovered to predict early response to therapies in the case of multi-treated ovarian cancer patients. The aim of our investigation was to identify a protein panel and the molecular pathways involved in chemotherapy response through a combination of studying proteomics and network enrichment analysis by considering a subset of samples from a clinical setting. Differential mass spectrometry studies were performed on 14 serum samples from patients with heavily pretreated platinum-resistant ovarian cancer who received the FOLFOX-4 regimen as a salvage therapy. The serum was analyzed at baseline time (T0) before FOLFOX-4 treatment, and before the second cycle of treatment (T1), with the aim of understanding if it was possible, after a first treatment cycle, to detect significant proteome changes that could be associated with patients responses to therapy. A total of 291 shared expressed proteins was identified and 12 proteins were finally selected between patients who attained partial response or no-response to chemotherapy when both response to therapy and time dependence (T0, T1) were considered in the statistical analysis. The protein panel included APOL1, GSN, GFI1, LCATL, MNA, LYVE1, ROR1, SHBG, SOD3, TEC, VPS18, and ZNF573. Using a bioinformatics network enrichment approach and metanalysis study, relationships between serum and cellular proteins were identified. An analysis of protein networks was conducted and identified at least three biological processes with functional and therapeutic significance in ovarian cancer, including lipoproteins metabolic process, structural component modulation in relation to cellular apoptosis and autophagy, and cellular oxidative stress response. Five proteins were almost independent from the network (LYVE1, ROR1, TEC, GFI1, and ZNF573). All proteins were associated with response to drug-resistant ovarian cancer resistant and were mechanistically connected to the pathways associated with cancer arrest. These results can be the basis for extending a biomarker discovery process to a clinical trial, as an early predictive tool of chemo-response to FOLFOX-4 of heavily treated ovarian cancer patients and for supporting the oncologist to continue or to interrupt the therapy.

Protein Analysis of A. halleri and N. caerulescens Hyperaccumulators When Exposed to Nano and Ionic Forms of Cd and Zn

Hyperaccumulator plant species growing on metal-rich soils can accumulate high quantity of metals and metalloids in aerial tissues, and several proteomic studies on the molecular mechanisms at the basis of metals resistance and hyperaccumulation have been published. Hyperaccumulator are also at the basis of the phytoremediation strategy to remove metals more efficiently from polluted soils or water. Arabidopsis halleri and Noccea caerulescens are both hyperaccumulators of metals and nano-metals. In this study, the change in some proteins in A. halleri and N. caerulescens was assessed after the growth in soil with cadmium and zinc, provided as sulphate salts (CdSO₄ and ZnSO₄) or sulfide quantum dots (CdS QDs and ZnS QDs). The protein extracts obtained from plants after 30 days of growth were analyzed by 2D-gel electrophoresis (2D SDS-PAGE) and identified by MALDI-TOF/TOF mass spectrometry. A bioinformatics analysis was carried out on quantitative protein differences between control and treated plants. In total, 43 proteins resulted in being significatively modulated in A. halleri, while 61 resulted in being modulated in N. caerulescens. Although these two plants are hyperaccumulator of both metals and nano-metals, at protein levels the mechanisms involved do not proceed in the same way, but at the end bring a similar physiological result.

Engineered Nanomaterial Exposure Affects Organelle Genetic Material Replication in Arabidopsis thaliana

Mitochondria and chloroplasts not only are cellular energy sources but also have important regulatory and developmental roles in cell function. CeO₂, FeOx ENMs, ZnS, CdS QDs, and relative metal salts were utilized in Murashige-Skoog (MS) synthetic growth medium at different concentrations (80-500 mg L^-1) and times of exposures (0-20 days). Analysis of physiological and molecular response of A. thaliana chloroplasts and mitochondrion demonstrates that ENMs increase or decrease functionality and organelle genome replication. Exposure to nanoscale CeO₂ and FeOx causes an 81-105% increase in biomass, whereas ZnS and CdS QDs yielded neutral or a 59% decrease in growth, respectively. Differential effects between ENMs and their corresponding metal salts highlight nanoscale-specific response pathways, which include energy production and oxidative stress response. Differences may be ascribed to ENM and the metal salt dissolution rate and the toxicity of the metal ion, which suggests eventual biotransformation processes occurring within the plant. With regard to specific effects on plastid (pt) and mitochondrial (mt) DNA, CdS QD exposure triggered potential variations at the substoichiometric level in the two organellar genomes, while nanoscale FeOx and ZnS QDs caused a 1- to 3-fold increase in ptDNA and mtDNA copy numbers. Nanoparticle CeO₂ exposure did not affect ptDNA and mtDNA stoichiometry. These findings suggest that modification in stoichiometry is a potential morpho-functional adaptive response to ENM exposure, triggered by modifications of bioenergetic redox balance, which leads to reducing the photosynthesis or cellular respiration rate.

Attractor-Specific and Common Expression Values in Random Boolean Network Models (with a Preliminary Look at Single-Cell Data)

Random Boolean Networks (RBNs for short) are strongly simplified models of gene regulatory networks (GRNs), which have also been widely studied as abstract models of complex systems and have been used to simulate different phenomena. We define the “common sea” (CS) as the set of nodes that take the same value in all the attractors of a given network realization, and the “specific part” (SP) as the set of all the other nodes, and we study their properties in different ensembles, generated with different parameter values. Both the CS and of the SP can be composed of one or more weakly connected components, which are emergent intermediate-level structures. We show that the study of these sets provides very important information about the behavior of the model. The distribution of distances between attractors is also examined. Moreover, we show how the notion of a “common sea” of genes can be used to analyze data from single-cell experiments.

Out-of-hospital cardiac arrest in COVID-19 era. A single center experience

Introduction

In the COVID-19 pandemic several adverse cardiovascular sequelae (myocarditis, AMI and heart failure) has been reported but it is unclear whether there is an influence of COVID-19 on incidence of out-of-hospital sudden death (OHCA) and its management by emergency medical services (EMS)

Aim

The aim of the study was to evaluate these items comparing OHCA during COVID-19 pandemic to that of pre-COVID era using the Progetto Vita Registry.

Method

We compared (OHCA) that occurred in Piacenza province during the first three months of COVID-19 outbreak (from February to April 2020, Period A) with those that occurred during the same period in 2019 (from February to April 2019, Period B) We collected data from the electronic database of the emergency medical system to identify patients affected by COVID-19, including both patient with symptoms suggestive of infection (history of fever before out-of-hospital cardiac arrest, with cough, dyspnea, or both) and patients with positive results of pharyngeal swabs test to detect SARS-CoV-2 obtained before the event or after death.

Results

1. Demographic characteristics of patients were similar in both periods (Period A 70/156 Female, mean age 79.2±5 yrs, Period B 39 Female, mean age 81.5±4 years,)

2. An higher number of OHCA were observed in the Period A vs Period B (A 156 cases vs B 78 cases, p 0.005). 68 cases (43%) of OHCA were associated with a COVID-19 disease

3. The EMS response time was longer in Period A vs B (A 16.4±4 min, vs B 11.1±3 min, p 0.05)

4. Initial cardiac rhythm was shockable in 10 subjects in the Period A (6,4%) and in 15 subjects in Period B (19.2%, p 005), possibly related to longer EMS response time

5. The global survival rate was higher in Period B vs A (B 5 patients, 6.4% vs 0 patients 0% p 0.05)

6. No one received cardiopulmonary resuscitation from bystanders in Period B.

Conclusion

During COVID-19 pandemic in Piacenza there was an increase in OCHA compared to the pre-COVID era. The COVID 19 Pandemic influences the bystanders attitude to practice an early cardiopulmonary resuscitation intervention and the performance of EMS, worsening the outcome of patients.

Funding Acknowledgement

Type of funding sources: None.

Rehabilitation in post-COVID patients. A single center experience

 

The COVID 19 disease is frequently associated with significant disability related to intensive care unit-acquired weakness, decontitioning, myopathies and neuropathies. However there are no data on the results of a specific rehabilitative treatment in this group of patients.

The aim of our work was to evaluate the effectiveness f a personalized rehabilitative therapy in group of post-COVID patients (A, 47 patients, average age 65.3±11.6 y, 27 M,) comparing the results with a group of post-cardiosurgical patients COVID 19 negative (B, 47 patients, average age 63.5±10.3 y, 29 M) evaluating the degree of clinical complexity (Rehabilitation Complexity Scale, RCS-E V13) and the degree of autonomy recovery (Six-minute walking test SMWT, Barthel Index, BI) pre and post-treatment.

In Group A patients the Rehabilitation program is associated with a significant improvement in autonomy recovery (BI admission 29.7±20 vs discharge 72.7±28.6 p<0.005, SMWT admission 146±25 vs 318±18 m, p<0.005) and in clinical complexity (RCS admission 10.9±1.1 vs discharge 5.3, p<0.05).

At admission the comparison between Group A vs B has show:

1. a reduced pre-rehabilitation hospital stay (days) in Group Vs A (B 8.2±2 vs 31±5 0.005)

2. a similar degrre of clinical complexity (RCS scale A 10.9±1.1 vs 1.6±11.2 p ns)

3. a greater loss autonomy in post-COVID patients (BI scale A 29.7±20 vs B 47.7±19, p 0.05; SMWT A 145±25 m vs B 255±18 m, p 0.05)

After a similar period of rehabilitation (A 29.7±12.8 days vs B 29.6±10 days, p ns) we observed in both Groups:

1. a reduction of clinical complexity ((RCS scale A 5.3±2 vs 6.6±2 p ns

2. an improvement of degree of autonomy recovery ((BI scale A 72.7±28 vs B 47.7±19, p ns; SMWT A 385±18 m vs B 410±25m, p ns)

Conclusions

Post-COVID patients show a greater loss of autonomy than post-cardiosurgery patients. Rehabilitative treatment has proven effective in ensuring adequate functional recovery with similar results to those obtained in the population of cardiological subjects COVID 19 negative.

Funding Acknowledgement

Type of funding sources: None.

Asymptotic Information-Theoretic Detection of Dynamical Organization in Complex Systems

The identification of emergent structures in complex dynamical systems is a formidable challenge. We propose a computationally efficient methodology to address such a challenge, based on modeling the state of the system as a set of random variables. Specifically, we present a sieving algorithm to navigate the huge space of all subsets of variables and compare them in terms of a simple index that can be computed without resorting to simulations. We obtain such a simple index by studying the asymptotic distribution of an information-theoretic measure of coordination among variables, when there is no coordination at all, which allows us to fairly compare subsets of variables having different cardinalities. We show that increasing the number of observations allows the identification of larger and larger subsets. As an example of relevant application, we make use of a paradigmatic case regarding the identification of groups in autocatalytic sets of reactions, a chemical situation related to the origin of life problem.

Evaluating the plasmon-exciton interaction in ZnO tetrapods coupled with gold nanostructures by nanoscale cathodoluminescence

Plasmon-exciton coupling is gaining increasing interest for enhancing the performance of optoelectronic, photonic and photo-catalytic devices. Herein we evaluate the interaction of excitons in zinc oxide tetrapods with surface plasmons of gold nanostructures with different morphologies. The gold nanostructures are grown in situ on ZnO tetrapods by means of a photochemical process, resulting in clean interfaces. The modification of the synthesis parameters results in different morphologies, as isolated nanoparticles, nano-domes or nanoparticles aggregates. Plasmon-exciton interaction is evaluated by means of cathodoluminescence spectroscopy and mapping at the nanoscale. The ZnO excitonic emission is strongly blue-shifted and broadened in close proximity of the gold nanostructures. This effect is explained by the formation of a Schottky barrier that is strongly mediated by the morphology of metal nanostructures.

The association of smoking status with glycemic control, metabolic profile and diabetic complications- Results of the Australian National Diabetes Audit (ANDA)

BACKGROUND

Tobacco smoking and diabetes mellitus contribute significantly to the overall health burden and mortality of Australians. We aimed to assess the relationship of smoking with glycemic control, metabolic profile and complications in Australian patients living with diabetes.

METHODS

We analysed the 2011-2017 biennial Australian National Diabetes Audit cross-sectional data. Patients were classified as current, past or never smokers. Linear (or quantile) and logistic regression models were used to assess for associations.

RESULTS

Data from 15,352 patients were analysed, including 72.2% with type 2 diabetes. Current smokers comprised 13.5% of the study population. Current and past smokers had a median HbA_1c that was 0.49% and 0.14% higher than never smokers, respectively, as well as higher triglyceride and lower HDL levels (all p values < .0001). Compared to never smokers, current smokers had higher odds of severe hypoglycemia and current and past smokers had higher odds of myocardial infarction, stroke, peripheral vascular disease, lower limb amputation, erectile dysfunction and peripheral neuropathy (all p values ≤.001), with no significant change over time.

CONCLUSION

When compared to never smokers, current and past smokers had poorer glycemic and lipid control and higher odds of macrovascular and microvascular complications. Despite this, current smoking remains prevalent among Australians with diabetes.

Improved electroless platinum contacts on CdZnTe X- and γ-rays detectors

Platinum is a promising candidate for the realization of blocking electrical contacts on cadmium-zinc-telluride (CdZnTe or CZT) radiation detectors. However, the poor mechanical adhesion of this metal often shortens the lifetime of the final device. In this work, a simple and effective procedure to obtain robust platinum contacts by electroless deposition is presented. Microscopical analysis revealed the final thickness and composition of the contact layer and its adhesion to the bulk crystal. The blocking nature of the Pt-CdZnTe junction, essential to obtain low noise devices, was confirmed by current–voltage measurements. The planar Pt-CdZnTe-Pt detectors showed good room temperature spectroscopic performance with energy resolution of 4% (2.4 keV) and 3% (3.7 keV) FWHM at 59.5 and 122.1 keV, respectively. Finally, we showed, for the first time, that platinum contacts allow the estimation of the carrier lifetime and mobility of both holes and electrons by using current transient measurements. This demonstrated the optimal hole extraction capability of such contacts.

Differences in toxicity, mitochondrial function and miRNome in human cells exposed in vitro to Cd as CdS quantum dots or ionic Cd

Cadmium is toxic to humans, although Cd-based quantum dots exerts less toxicity. Human hepatocellular carcinoma cells (HepG2) and macrophages (THP-1) were exposed to ionic Cd, Cd(II), and cadmium sulfide quantum dots (CdS QDs), and cell viability, cell integrity, Cd accumulation, mitochondrial function and miRNome profile were evaluated. Cell-type and Cd form-specific responses were found: CdS QDs affected cell viability more in HepG2 than in THP-1; respective IC₂₀ values were ∼3 and ∼50 μg ml^-1. In both cell types, Cd(II) exerted greater effects on viability. Mitochondrial membrane function in HepG2 cells was reduced 70 % with 40 μg ml^-1 CdS QDs but was totally inhibited by Cd(II) at corresponding amounts. In THP-1 cells, CdS QDs has less effect on mitochondrial function; 50 μg ml^-1 CdS QDs or equivalent Cd(II) caused 30 % reduction or total inhibition, respectively. The different in vitro effects of CdS QDs were unrelated to Cd uptake, which was greater in THP-1 cells. For both cell types, changes in the expression of miRNAs (miR-222, miR-181a, miR-142-3p, miR-15) were found with CdS QDs, which may be used as biomarkers of hazard nanomaterial exposure. The cell-specific miRNome profiles were indicative of a more conservative autophagic response in THP-1 and as apoptosis as in HepG2.

Data on miRNome changes in human cells exposed to nano- or ionic- forms of Cadmium

The data included in this paper are associated with a research article entitled 'Differences in toxicity, mitochondrial function and miRNome in human cells exposed in vitro to Cd as CdS quantum dots or ionic Cd' [1]. The article concerns the use of miRNAs as biomarkers for engineered nanomaterials (ENMs) risk assessment. Two different type of human cells, HepG2 and THP-1, were exposed to different forms of Cadmium: nanoscale, as CdS quantum dots (CdS QDs), and ionic, as CdSO₄ 8/3 –hydrate (Cd(II)). The cells were treated with sub-toxic doses of CdS QDs; 3 µg ml⁻¹ in HepG2 and 6.4 µg ml⁻¹ and 50 µg ml⁻¹ in THP-1, as well as equivalent cadmium doses as Cd(II). In this dataset, changes in expression levels of miRNAs are reported. In addition, GO enrichment analyses of target genes of miRNAs modulated by Cd stress, network analysis of the microRNome and an in silico pathway analysis are also reported. These data enhance and also summarize much of the data independently presented in the research article and therefore, must be considered as supplementary.

Cadmium sulfide quantum dots impact Arabidopsis thaliana physiology and morphology

The differential mechanisms of CdS QDs (Quantum Dots) and Cd ion toxicity to Arabidopsis thaliana (L.) Heynh were investigated. Plants were exposed to 40 and 60 mg L^-1 for CdS QDs and 76.9 and 115.2 mg L^-1 CdSO₄·7H₂O and toxicity was evaluated at 5, 20, 35 (T5, T20, T35) days after exposure. Oxidative stress upon exposure was evaluated by biochemical essays targeting non-enzymatic oxidative stress physiological parameters, including respiration efficiency, total chlorophylls, carotenoids, ABTS and DPPH radicals reduction, total phenolics, GSH redox state, lipid peroxidation. Total Cd in plants was measured with AAS. Root and leaf morphology and element content were assessed in vivo utilizing low-vacuum Environmental Scanning Electron Microscopy (ESEM) with X-ray microanalysis (EDX). This integrated approach allowed identification of unique nanoscale CdS QDs toxicity to the plants that was distinct from CdSO₄ exposure. The analyses highlighted that CdS QDs and Cd ions effects are modulated by the developmental stage of the plant, starting from T20 till T35 the plant development was modulated by the treatments, in particular CdS QDs induced early flowering. Both treatments induced Fe accumulation in roots, but at different intensities, while CdS QDs was associated with Mn increase into plant leaf. CdSO₄ elicited higher levels of oxidative stress compared with QDs, especially the former treatment caused more intense respiration damages and reduction in chlorophyll and carotenoids than the latter. The two types of treatments impact differently on root and leaf morphology.

[Integrating close relatives of people experiencing schizophrenia in the mental health system]

OBJECTIVES

Schizophrenia is a long-term, stigmatized disease which often leads to social impairment, unemployment and isolation, with heavy negative social and psychological consequences both on patients and their families. Close relatives' perceptions of the illness have an impact on their mood, and then on the course of the patient's disease itself. In this context, our objective is to evaluate the perceptions of French close relatives of people with schizophrenia or schizophrenia spectrum disorders, about the disease itself, as well as their experience within the mental healthcare system.

METHODS

Our population is constituted of close relatives of people experiencing schizophrenia or schizophrenia spectrum disorders, recruited through an active patient and families association. We used a French translation of a standardized questionnaire, the Brief Illness Perception Questionnaire, as well as an extensive semi-structured interview assessing the experience of the mental healthcare system (diagnosis divulgation, information about disease and treatment, family psychoeducation, hospitalization experience, and access to health professionals). Some questions in the last were open-ended questions, which allowed us to gather detailed and personal responses, in order to be able to illustrate our quantitative findings with brief clinical cases.

RESULTS

Among the 27 close relatives included in our research, results to the standardized questionnaires show threatening perceptions of the disease, in particular regarding the probable duration of the disease and the frequency of symptoms. In our study, a better access to diagnosis is associated with a shorter perceived probable duration of the disease, while an easier communication with healthcare professionals (in particular nurses) is associated with the perception of a better efficiency of the treatment. Family psychoeducation seems to be associated with the perception of less frequent symptoms. When the patient lives independently or is older, close relatives of our sample perceive a higher risk of chronicity of the disease. Our results tend to confirm the available literature on the subject of information towards families in psychiatric services: indeed, studies, especially in the field of nursing research, have shown that families tend to feel excluded from care processes and from useful information exchanges about the patient's illness. Our study also confirms the fact that family psychoeducation seems to reduce the frequency of present symptoms in the patient as perceived by the close relative. This effect could be caused by a better understanding of the real symptoms or by an enhancement of the family mood and functioning. Even if the patient's hospitalization was a difficult or very difficult experience for close relatives, it showed no relationship with their illness negative perceptions. Sociodemographic variables of the patient, such as age or the fact of living in an independent household, were associated in our research with the close relatives' view of a higher potential chronicity of the illness; this could be explained by a different stage of acceptation of the illness when compared to close relatives taking care of a younger or still dependent patient.

CONCLUSIONS

Our results plead for further research on a larger and less homogeneous sample. Confirming our findings could help build useful recommendations leading to better integrated families who currently seem to feel relatively isolated and exclused in the healthcare process, despite the strategic role they could play and despite the many recommendations of public health policies in that matter. Efforts should continue to be made to reach the goal of a better inclusion of families and close relatives of people experiencing schizophrenia or schizophrenia spectrum disorders, in particular in the field of information and communication with health professionals, both areas which seem to have a potential effect on close relatives' illness negative perceptions. Family psychoeducation deserves more attention and should be more systematically proposed to French families with an easier and free access.

Kinetic Rate Constants of Gold Nanoparticle Deposition on Silicon

We fabricated gold nanoparticles on nanoporous silicon microparticles using electroless deposition in a hydrofluoric acid solution containing gold chloride. The reaction was followed by UV spectrometer analysis of the absorbance of the solution (proportional to the nanoparticle concentration) for two temperatures (20 and 50 °C). The results indicate that the process is autocatalytic, described by a pseudo-first-order reaction, the apparent rate constant k_obs of which was determined by utilizing UV spectrometer data. We found that the reaction rate constant at 20 °C is 7 × 10^-3 s^-1 and that at 50 °C is 2.9 × 10^-2 s^-1. Scanning electron microscope (SEM) analysis of samples and diffusion-limited aggregation (DLA) simulations were used to validate the results. This study aims to resolve the kinetics of the electroless deposition of gold on silicon at the nanoscale, in the present state of art missing a quantitative characterization, for certain conditions of growth and given values of temperature and concentration of the reagents. Results may have applications to the synthesis of gold nanoparticles and their use as nanosensors, drug delivery systems, or metal nanometamaterials with advanced optical properties.

Effect of family psychoeducation and access to information on illness negative perceptions: a study on French families of persons experiencing schizophrenia

Background

A better understanding of schizophrenia, a chronic disease often leading to heavy negative consequences both on users and families, has been shown to reduce those difficulties. Studies recommend family psychoeducation, as this structured educative intervention reduces parents’ depressive symptoms, enhances family mood, and decreases risks of relapse for users. Our objective is to assess whether family psychoeducation and access to information has an effect on close relatives’ illness negative perceptions.

Methods

Our sample consists in 27 close relatives of persons with schizophrenia. We used a semi-structured interview assessing access to psycho-education and information about illness and diagnosis. We also used the Brief Illness Perception Questionnaire, which explores various illness negative perceptions, as well as probable causes of the illness.

Results

A better access to diagnosis for families is associated with a shorter perceived probable illness duration (p=.044). Family psychoeducation programs, followed by 38,5% of close relatives, reduces their perception of the frequency of user’s present symptoms (p=.029). This could be caused by a better understanding of real symptoms, or by an enhancement of family mood. Also, family psychoeducation has an effect on causal attributions: 50% of close relatives with access to family psychoeducation believed in a substance abuse causality, opposed to 12,5% of the others (p=.036).

Conclusions

Family psychoeducation could help allowing a shift in causal attributions and more generally enhancing family reaction to the disease, which, in turn, can have an impact on the user’s recovery process. Thus, this intervention deserves more attention and should be more systematically proposed to French families, alongside with an easier access to information.

Foreign body granuloma in the maxillofacial region: a case report

Foreign bodies can penetrate in soft tissues of the maxillofacial region through injuries and cutaneous lacerations from trauma. Most commonly found bodies are glass, metal and wood. We report the case of a 50-year-old male patient who came to our maxillofacial department complaining about the presence of an intraoral nodule located in the right upper gingival mucosa. The patient reported the story of a road accident, three months earlier, falling from a scooter without the aid of a protective helmet.

Sustainable Growth and Synchronization in Protocell Models

The growth of a population of protocells requires that the two key processes of replication of the protogenetic material and reproduction of the whole protocell take place at the same rate. While in many ODE-based models such synchronization spontaneously develops, this does not happen in the important case of quadratic growth terms. Here we show that spontaneous synchronization can be recovered (i) by requiring that the transmembrane diffusion of precursors takes place at a finite rate, or (ii) by introducing a finite lifetime of the molecular complexes. We then consider reaction networks that grow by the addition of newly synthesized chemicals in a binary polymer model, and analyze their behaviors in growing and dividing protocells, thereby confirming the importance of (i) and (ii) for synchronization. We describe some interesting phenomena (like long-term oscillations of duplication times) and show that the presence of food-generated autocatalytic cycles is not sufficient to guarantee synchronization: in the case of cycles with a complex structure, it is often observed that only some subcycles survive and synchronize, while others die out. This shows the importance of truly dynamic models that can uncover effects that cannot be detected by static graph theoretical analyses.

In Vivo-In Vitro Comparative Toxicology of Cadmium Sulphide Quantum Dots in the Model Organism Saccharomyces cerevisiae

The aim of this work was to use the yeast Saccharomyces cerevisiae as a tool for toxicogenomic studies of Engineered Nanomaterials (ENMs) risk assessment, in particular focusing on cadmium based quantum dots (CdS QDs). This model has been exploited for its peculiar features: a short replication time, growth on both fermentable and oxidizable carbon sources, and for the contextual availability of genome wide information in the form of genetic maps, DNA microarray, and collections of barcoded mutants. The comparison of the whole genome analysis with the microarray experiments (99.9% coverage) and with the phenotypic analysis of 4688 barcoded haploid mutants (80.2% coverage), shed light on the genes involved in the response to CdS QDs, both in vivo and in vitro. The results have clarified the mechanisms involved in the exposure to CdS QDs, and whether these ENMs and Cd²⁺ exploited different pathways of response, in particular related to oxidative stress and to the maintenance of mitochondrial integrity and function. Saccharomyces cerevisiae remains a versatile and robust alternative for organismal toxicological studies, with a high level of heuristic insights into the toxicology of more complex eukaryotes, including mammals.

Cortical-like mini-columns of neuronal cells on zinc oxide nanowire surfaces

A long-standing goal of neuroscience is a theory that explains the formation of the minicolumns in the cerebral cortex. Minicolumns are the elementary computational units of the mature neocortex. Here, we use zinc oxide nanowires with controlled topography as substrates for neural-cell growth. We observe that neuronal cells form networks where the networks characteristics exhibit a high sensitivity to the topography of the nanowires. For certain values of nanowires density and fractal dimension, neuronal networks express small world attributes, with enhanced information flows. We observe that neurons in these networks congregate in superclusters of approximately 200 neurons. We demonstrate that this number is not coincidental: the maximum number of cells in a supercluster is limited by the competition between the binding energy between cells, adhesion to the substrate, and the kinetic energy of the system. Since cortical minicolumns have similar size, similar anatomical and topological characteristics of neuronal superclusters on nanowires surfaces, we conjecture that the formation of cortical minicolumns is likewise guided by the interplay between energy minimization, information optimization and topology. For the first time, we provide a clear account of the mechanisms of formation of the minicolumns in the brain.

Functionalization of carbon fiber tows with ZnO nanorods for stress sensor integration in smart composite materials

The physical and operating principle of a stress sensor, based on two crossing carbon fibers functionalized with ZnO nanorod-shaped nanostructures, was recently demonstrated. The functionalization process has been here extended to tows made of one thousand fibers, like those commonly used in industrial processing, to prove the idea that the same working principle can be exploited in the creation of smart sensing carbon fiber composites. A stress-sensing device made of two functionalized tows, fixed with epoxy resin and crossing like in a typical carbon fiber texture, was successfully tested. Piezoelectric properties of single nanorods, as well as those of the test device, were measured and discussed.

Silica diatom shells tailored with Au nanoparticles enable sensitive analysis of molecules for biological, safety and environment applications

Diatom shells are a natural, theoretically unlimited material composed of silicon dioxide, with regular patterns of pores penetrating through their surface. For their characteristics, diatom shells show promise to be used as low cost, highly efficient drug carriers, sensor devices or other micro-devices. Here, we demonstrate diatom shells functionalized with gold nanoparticles for the harvesting and detection of biological analytes (bovine serum albumin-BSA) and chemical pollutants (mineral oil) in low abundance ranges, for applications in bioengineering, medicine, safety, and pollution monitoring.

An in vivo biosensing, biomimetic electrochemical transistor with applications in plant science and precision farming

The in vivo monitoring of key plant physiology parameters will be a key enabler of precision farming. Here, a biomimetic textile-based biosensor, which can be inserted directly into plant tissue is presented: the device is able to monitor, in vivo and in real time, variations in the solute content of the plant sap. The biosensor has no detectable effect on the plant's morphology even after six weeks of continuous operation. The continuous monitoring of the sap electrolyte concentration in a growing tomato plant revealed a circadian pattern of variation. The biosensor has the potential to detect the signs of abiotic stress, and therefore might be exploited as a powerful tool to study plant physiology and to increase tomato growth sustainability. Also, it can continuously communicate the plant health status, thus potentially driving the whole farm management in the frame of smart agriculture.

Inter- and intraspecific variability in physiological traits and post-anoxia recovery of photosynthetic efficiency in grasses under oxygen deprivation

Low oxygen conditions occur in grass sites due to high and frequent precipitation, poor soil quality, and over-irrigation followed by slow drainage. Three warm-season and one cool-season grass were analyzed at metabolic level during a time-course experiment performed in a controlled anoxic environment. Prolonged oxygen depletion proved detrimental by leading to premature death to all the species, with the exception of seashore paspalum. Moreover, the anoxia tolerance observed in these grasses has been associated with slow use of carbohydrates, rather than with their relative abundance, which was more important than their antioxidant capacity. Further physiological characterization of eight seashore paspalum genotypes to anoxia was also performed, by examining the variation in photosystem II (PSII) efficiency and gas exchange during post-anoxia recovery. Multivariate analysis highlighted the presence of three main clusters of seashore paspalum genotypes, characterized by different ability to restore the PSII photochemistry during recovery after one day of anoxia. Taken together, our data demonstrate that the analysis of post-anoxia recovery of fluorescence and gas exchange parameters can represent a fast and reliable indicator for selecting species and cultivars more able to acclimate their photosynthetic apparatus.

Emergency treatment of hypoglycaemia: a guideline and evidence review

AIM

To examine the current treatment guidelines for the emergency management of hypoglycaemia and the evidence underpinning recommendations.

METHODS

International diabetes agencies were searched for hypoglycaemia treatment guidelines. Guidelines were assessed using the Appraisal of Guidelines Research and Evaluation II (AGREE II) instrument. An electronic database search was conducted for evidence regarding emergency treatment of hypoglycaemia in adults, and relevant articles were critically appraised.

RESULTS

Of the international diabetes agencies, six sets of guidelines were deemed relevant and of sufficient detail for appraisal by AGREE II. The evidence search returned 2649 articles, of which 17 pertaining to the emergency management of hypoglycaemia were included. High-quality evidence for the management of hypoglycaemia was lacking, limiting treatment recommendations. In general, guidelines and studies were somewhat concordant and recommended 15-20 g of oral glucose or sucrose, repeated after 10-15 min for treatment of the responsive adult, and 10% intravenous dextrose or 1 mg intramuscular glucagon for treatment of the unresponsive adult. No evidence was found for other treatment approaches.

CONCLUSION

Evidence for the emergency treatment of hypoglycaemia in adults is limited, is often low grade and mostly pre-dates contemporary management of diabetes. Guideline recommendations are limited by the lack of randomized trials. Further high-quality studies are required to inform the optimum management of this frequently occurring emergency condition.

Nucleo-mitochondrial interaction of yeast in response to cadmium sulfide quantum dot exposure

Cell sensitivity to quantum dots (QDs) has been attributed to a cascade triggered by oxidative stress leading to apoptosis. The role and function of mitochondria in animal cells are well understood but little information is available on the complex genetic networks that regulate nucleo-mitochondrial interaction. The effect of CdS QD exposure in yeast Saccharomyces cerevisiae was assessed under conditions of limited lethality (<10%), using cell physiological and morphological endpoints. Whole-genomic array analysis and the screening of a deletion mutant library were also carried out. The results showed that QDs: increased the level of reactive oxygen species (ROS) and decreased the level of reduced vs oxidized glutathione (GSH/GSSG); reduced oxygen consumption and the abundance of respiratory cytochromes; disrupted mitochondrial membrane potentials and affected mitochondrial morphology. Exposure affected the capacity of cells to grow on galactose, which requires nucleo-mitochondrial involvement. However, QDs exposure did not materially induce respiratory deficient (RD) mutants but only RD phenocopies. All of these cellular changes were correlated with several key nuclear genes, including TOM5 and FKS1, involved in the maintenance of mitochondrial organization and function. The consequences of these cellular effects are discussed in terms of dysregulation of cell function in response to these "pathological mitochondria".

Charge-separation enhancement in inverted polymer solar cells by molecular-level triple heterojunction: NiO-np:P3HT:PCBM

Hole collection and transport are crucial physical processes in bulk-heterojunction (BHJ) solar cells, which represent major bottlenecks due to their limitations in power conversion efficiency (PCE). Hence, a more efficient alternative is needed to accept and transport holes to the collection electrode in BHJ solar cells. Here, we bring both electron and hole collection centres close to the point of exciton generation by infiltrating P3HT poly(3-hexylthiophene):PCBM ([6,6]-phenyl-C61-butyric acid methyl ester) blend into a highly porous interconnected p-type NiO-nanoparticle (NiO-np) network, through solvent-assisted grafting. In this study, a hybrid polymer solar cell is demonstrated with a P3HT:PCBM:NiO-np triple-heterojunction active layer which showed greatly improved rectification behaviour, long electron lifetime and generated higher PCE of 4% under AM 1.5 solar illumination with a 75% increase in PCE with respect to the P3HT:PCBM device. The optimum NiO-np amount and active-layer thickness were found to be 2% and 250 nm, respectively.

Modeling, Fabrication and Testing of a Customizable Micromachined Hotplate for Sensor Applications

In the sensors field the active sensing material frequently needs a controlled temperature in order to work properly. In microsystems technology, micro-machined hotplates represent a platform consisting of a thin suspended membrane where the sensing material can be deposited, usually integrating electrical stimuli and temperature readout. The micro-hotplate ensures a series of advantages such as miniaturized size, fast response, high sensitivity, low power consumption and selectivity for chemical sensing. This work compares the coplanar and the buried approach for the micro-hotplate heaters design with the aim to optimize the fabrication process and to propose a guideline for the choice of the suitable design with respect to the applications. In particular, robust Finite Element Method (FEM) models are set up in order to predict the electrical and thermal behavior of the micro-hotplates. The multiphysics approach used for the simulation allows to match as close as possible the actual device to the predictive model: geometries, materials, physics have been carefully linked to the fabricated devices to obtain the best possible accuracy. The materials involved in the fabrication process are accurately selected in order to improve the yield of the process and the performance of the devices. The fabricated micro-hotplates are able to warm the active region up to 400 °C (with a corresponding power consumption equal to 250 mW @ 400 °C) with a uniform temperature distribution in the buried micro-hotplate and a controlled temperature gradient in the coplanar one. A response time of about 70 ms was obtained on the virtual model, which perfectly agrees with the one measured on the fabricated device. Besides morphological, electrical and thermal characterizations, this work includes reliability tests in static and dynamic modes.

A new method to integrate ZnO nano-tetrapods on MEMS micro-hotplates for large scale gas sensor production

A new method, which is easily scalable to large scale production, has been developed to obtain gas sensor devices based on zinc oxide (ZnO) nanostructures with a 'tetrapod' shape. The method can be easily extended to other kinds of nanostructures and is based on the deposition of ZnO nanostructures through polymeric masks by centrifugation, directly onto properly designed MEMS micro-hotplates. The micromachined devices, after the mask is peeled off, are ready for electrical bonding and sensing test. Sensor response has been successfully measured for some gases and volatile organic compounds with different chemical properties (ethanol, methane, nitrogen dioxide, hydrogen sulfide).

Geometrical Patterning of Super-Hydrophobic Biosensing Transistors Enables Space and Time Resolved Analysis of Biological Mixtures

PEDOT

PSS is a conductive polymer that can be integrated into last generation Organic Electrochemical Transistor (OECT) devices for biological inspection, identification and analysis. While a variety of reports in literature demonstrated the chemical and biological sensitivity of these devices, still their ability in resolving complex mixtures remains controversial. Similar OECT devices display good time dynamics behavior but lack spatial resolution. In this work, we integrated

PEDOT

PSS with patterns of super-hydrophobic pillars in which a finite number of those pillars is independently controlled for site-selective measurement of a solution. We obtained a multifunctional, hierarchical OECT device that bridges the micro- to the nano-scales for specific, combined time and space resolved analysis of the sample. Due to super-hydrophobic surface properties, the biological species in the drop are driven by convection, diffusion, and the externally applied electric field: the balance/unbalance between these forces will cause the molecules to be transported differently within its volume depending on particle size thus realizing a size-selective separation. Within this framework, the separation and identification of two different molecules, namely Cetyl Trimethyl Ammonium Bromid (CTAB) and adrenaline, in a biological mixture have been demonstrated, showing that geometrical control at the micro-nano scale impart unprecedented selectivity to the devices.

The Search for Candidate Relevant Subsets of Variables in Complex Systems

We describe a method to identify relevant subsets of variables, useful to understand the organization of a dynamical system. The variables belonging to a relevant subset should have a strong integration with the other variables of the same relevant subset, and a much weaker interaction with the other system variables. On this basis, extending previous work on neural networks, an information-theoretic measure, the dynamical cluster index, is introduced in order to identify good candidate relevant subsets. The method does not require any previous knowledge of the relationships among the system variables, but relies on observations of their values over time. We show its usefulness in several application domains, including: (i) random Boolean networks, where the whole network is made of different subnetworks with different topological relationships (independent or interacting subnetworks); (ii) leader-follower dynamics, subject to noise and fluctuations; (iii) catalytic reaction networks in a flow reactor; (iv) the MAPK signaling pathway in eukaryotes. The validity of the method has been tested in cases where the data are generated by a known dynamical model and the dynamical cluster index is applied in order to uncover significant aspects of its organization; however, it is important that it can also be applied to time series coming from field data without any reference to a model. Given that it is based on relative frequencies of sets of values, the method could be applied also to cases where the data are not ordered in time. Several indications to improve the scope and effectiveness of the dynamical cluster index to analyze the organization of complex systems are finally given.

Branched gold nanoparticles on ZnO 3D architecture as biomedical SERS sensors

We present a new 3D surface-enhanced Raman spectroscopy substrate made of branched gold nanoparticles supported on ZnO tetrapods that was proved to be effective in different biomedical application such as drug detection and cancer cells analysis.

The Proteomic Response of Arabidopsis thaliana to Cadmium Sulfide Quantum Dots, and Its Correlation with the Transcriptomic Response

A fuller understanding of the interaction between plants and engineered nanomaterials is of topical relevance because the latter are beginning to find applications in agriculture and the food industry. There is a growing need to establish objective safety criteria for their use. The recognition of two independent Arabidopsis thaliana mutants displaying a greater level of tolerance than the wild type plant to exposure to cadmium sulfide quantum dots (CdS QDs) has offered the opportunity to characterize the tolerance response at the physiological, transcriptomic, and proteomic levels. Here, a proteomics-based comparison confirmed the conclusions drawn from an earlier transcriptomic analysis that the two mutants responded to CdS QD exposure differently both to the wild type and to each other. Just over half of the proteomic changes mirrored documented changes at the level of gene transcription, but a substantial number of transcript/gene product pairs were altered in the opposite direction. An interpretation of the discrepancies is given, along with some considerations regarding the use and significance of -omics when monitoring the potential toxicity of ENMs for health and environment.

Growth and division in a dynamic protocell model

In this paper a new model of growing and dividing protocells is described, whose main features are (i) a lipid container that grows according to the composition of the molecular milieu (ii) a set of “genetic memory molecules” (GMMs) that undergo catalytic reactions in the internal aqueous phase and (iii) a set of stochastic kinetic equations for the GMMs. The mass exchange between the external environment and the internal phase is described by simulating a semipermeable membrane and a flow driven by the differences in chemical potentials, thereby avoiding to resort to sometimes misleading simplifications, e.g., that of a flow reactor. Under simple assumptions, it is shown that synchronization takes place between the rate of replication of the GMMs and that of the container, provided that the set of reactions hosts a so-called RAF (Reflexive Autocatalytic, Food-generated) set whose influence on synchronization is hereafter discussed. It is also shown that a slight modification of the basic model that takes into account a rate-limiting term, makes possible the growth of novelties, allowing in such a way suitable evolution: so the model represents an effective basis for understanding the main abstract properties of populations of protocells.

Selective response inversion to NO₂ and acetic acid in ZnO and CdS nanocomposite gas sensor

High sensitivity zinc oxide (ZnO) tetrapods (TPs) have been functionalized by nucleating cadmium sulphide (CdS) nanoparticles (NPs) directly on their surface with a spotted coverage thanks to an optimized synthesis in dimethylformamide (DMF). The obtained hybrid coupled material has been used to realize a gas sensing device with a highly porous nanostructured network, in which the proper alternation of ZnO-TPs and CdS-NPs gives rise to unconventional chemoresistive behaviours. Among the different tested gases and vapours, the sensor showed a unique fingerprint response-inversion between 300 °C and 400 °C only for nitrogen dioxide (NO2) and acetic acid (CH3COOH).