Spatially Extended Charge Density Wave Switching by Nanoscale Local Manipulation in a VTe2 Monolayer

Monolayer transition metal dichalcogenide VTe2 exhibits multiple charge density wave (CDW) phases, mainly (4 × 4) and (4 × 1). Here we report facile dynamic and tens-of-nanometer scale switching between these CDW phases with gentle bias pulses in scanning tunneling microscopy. Bias pulses purposely stimulate a reversible random CDW symmetry change between the isotropic (4 × 4) and anisotropic (4 × 1) CDWs, as well as CDW phase slips and rotation. The switching threshold of ∼1.0 V is independent of bias polarity, and the switching rate varies linearly with the tunneling current. Density functional theory calculations indicate that a coherent CDW phase switching incurs an energy barrier of ∼2.0-3.0 eV per (4 × 4) unit cell. While there is a challenge in understanding the observed large-area CDW random fluttering, we provide some possible explanations. The ability to manipulate electronic CDW phases sheds new light on tailoring CDW properties on demand.

Weight Status Prediction Using a Neuron Network Based on Individual and Behavioral Data

BACKGROUND

The worldwide epidemic of weight gain and obesity is increasing in response to the evolution of lifestyles. Our aim is to provide a new predictive method for current and future weight status estimation based on individual and behavioral characteristics.

METHODS

The data of 273 normal (NW), overweight (OW) and obese (OB) subjects were assigned either to the training or to the test sample. The multi-layer perceptron classifier (MLP) classified the data into one of the three weight statuses (NW, OW, OB), and the classification model accuracy was determined using the test dataset and the confusion matrix.

RESULTS

On the basis of age, height, light-intensity physical activity and the daily number of vegetable portions consumed, the multi-layer perceptron classifier achieved 75.8% accuracy with 90.3% for NW, 34.2% for OW and 66.7% for OB. The NW and OW subjects showed the highest and the lowest number of true positives, respectively. The OW subjects were very often confused with NW. The OB subjects were confused with OW or NW 16.6% of the time.

CONCLUSIONS

To increase the accuracy of the classification, a greater number of data and/or variables are needed.

Interface versus Bulk Light-Induced Switching in Spin-Crossover Molecular Ultrathin Films Adsorbed on a Metallic Surface

Spin-crossover molecules present the unique property of having two spin states that can be controlled by light excitation at low temperature. Here, we report on the photoexcitation of [Fe^II((3, 5-(CH₃)₂Pz)₃BH)₂] (Pz = pyrazolyl) ultrathin films, with thicknesses ranging from 0.9 to 5.3 monolayers, adsorbed on Cu(111) substrate. Using X-ray absorption spectroscopy measurements, we confirm the anomalous light-induced spin-state switching observed for sub-monolayer coverage and demonstrate that it is confined to the first molecular layer in contact with the metallic substrate. For higher coverages, the well-known light-induced excited spin-state trapping effect is recovered. Combining continuous light excitation with thermal cycling, we demonstrate that at low temperature light-induced thermal hysteresis is measured for the thicker films, while for sub-monolayer coverage, the light enables extension of the thermal conversion over a large temperature range. Mechanoelastic simulations underline that, due to the intermolecular interactions, opposite behaviors are observed in the different layers composing the films.

Experience of memory: transfer of the motor feeling of fluency linked to our interaction with the environment

In the field of memory, it is now admitted that an experience of memory is not only the consequence of the activation of a precise content, but also results from an inference associated with the transfer of the manner in which the process was carried out (i.e., fluency) in addition to the transfer of the process itself. The aim of this work was to show that experience of memory is also associated with the fluency that is due to the transfer of a processing carried out in our past interactions with our environment, independently the fluency associated with the stimulus in progress. First, participants performed a perceptual discrimination task (geometric shapes: circle or square) that involves a fluent or a non-fluent gesture to respond. Motor fluency vs. non-fluency was implicitly associated with the colour of the geometric shapes. Second, participants had to perform a classical memory recognition task. During the recognition phase, items appeared either with the colour associated with motor fluency or with the colour associated with motor non-fluency. We used a Go-NoGo task to avoid having a confused factor (response space). Results show that items were better recognised with a colour associated with motor fluency than with a colour associated with non-motor fluency. These findings support the idea that an experience of memory is also associated with the transfer of the motor feeling of fluency linked to our past interactions with the environment.

Negative Differential Resistance in Spin-Crossover Molecular Devices

We demonstrate, based on low-temperature scanning tunneling microscopy (STM) and spectroscopy, a pronounced negative differential resistance (NDR) in spin-crossover (SCO) molecular devices, where a Fe^II SCO molecule is deposited on surfaces. The STM measurements reveal that the NDR is robust with respect to substrate materials, temperature, and the number of SCO layers. This indicates that the NDR is intrinsically related to the electronic structure of the SCO molecule. Experimental results are supported by density functional theory (DFT) with nonequilibrium Green's function (NEGF) calculations and a generic theoretical model. While the DFT+NEGF calculations reproduce NDR for a special atomically sharp STM tip, the effect is attributed to the energy-dependent tip density of states rather than the molecule itself. We, therefore, propose a Coulomb blockade model involving three molecular orbitals with very different spatial localization as suggested by the molecular electronic structure.

Objective evaluation of the first post-lockdown on physical activity, sedentary behavior and food choice in a sample of French young adult students

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Young adult students spent more time in moderate physical activity post lockdown.

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Sedentary behaviors remained stable for the two periods in young adult students.

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Food balance score was better during than after the lockdown in young adult students.

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Total number of food portions decreased in female students after the lockdown.

From mid-March through early May 2020, France limited outdoor activities to one hour per day because of the Covid-19 epidemic. This inside lockdown could have a lasting impact on post-lockdown sedentary and physical activities and food choice. The aim of this study is to compare behaviors before and after the lockdown in a sample of French young adult students (sex ratio = 1:1, 22 ± 3 y old). Over a period of 4 days in both April and after mid-May 2020, 50 students used the WellBeNet smartphone application to record accelerometry data to evaluate their sedentary behavior and physical activity, and food consumption. Some behaviors remained stable for both periods: sedentary behavior, light-intensity activity, the number of meals per day, the number of portions of fruits, nuts, dairy products, vegetables, legumes and meat-fish-egg. Moderate-intensity activity duration was higher (+1.4%, p < 0.0001), whereas the food balance score was lower (−0.3, p = 0.06) during the return to free-living conditions. Different food behaviors in male and female students were observed between the two periods. The total daily number of food portions and of whole starchy products post lockdown was lower in female students (−1.07 and −0.47 portion/d, p = 0.07 and 0.04) but remained stable in male students, post-lockdown. The consumption of snacks was similar in men and women during the lockdown, whereas it was higher in men post-lockdown (+0.8 portion/d, p = 0.01). During the COVID-19 lockdown, food consumption choice was better overall and the moderate-intensity physical activity level was lower compared with the free-living subsequent period.

Identification and Manipulation of Defects in Black Phosphorus

We identify and manipulate commonly occurring defects in black phosphorus, combining scanning tunneling microscopy experiments with density functional theory calculations. A ubiquitous defect, imaged at negative bias as a bright dumbbell extending over several nanometers, is shown to arise from a substitutional Sn impurity in the second sublayer. Another frequently observed defect type is identified as arising from an interstitial Sn atom; this defect can be switched to a more stable configuration consisting of a Sn substitutional defect + P adatom, by application of an electrical pulse via the STM tip. DFT calculations show that this pulse-induced structural transition switches the system from a non-magnetic configuration to a magnetic one. We introduce States Projected Onto Individual Layers (SPOIL) quantities which provide information about atom-wise and orbital-wise contributions to bias-dependent features observed in STM images.

Possible Impact of a 12-Month Web- and Smartphone-Based Program to Improve Long-term Physical Activity in Patients Attending Spa Therapy: Randomized Controlled Trial

Background

Lack of physical activity (PA) and sedentary behaviors are leading risk factors for noncommunicable diseases (NCDs). Web- and smartphone-based interventions are effective in increasing PA in older adults and in patients with NCD. In many countries, spa therapy, commonly prescribed to patients with NCD, represents an ideal context to initiating lifestyle changes.

Objective

This study aimed to evaluate, in patients attending spa therapy, the effectiveness of an intervention combining a face-to-face coaching and, when returning home, a web- and smartphone-based PA program on the achievement of PA guidelines (PAG) 12 months after the end of spa therapy.

Methods

This was a 12-month, prospective, parallel-group randomized controlled trial. Patients were enrolled during spa therapy and randomized 1:1 to intervention or control group who received PA usual advice. From the end of spa therapy, PA, weight, waist circumference, and quality of life of the participants were assessed by phone every 2 months. Primary outcome was meeting PAG (PA ≥600 metabolic equivalent of task) at 12 months. Secondary outcomes were meeting current PAG at 6 months; sedentary time, weight, waist circumference, PA, and quality of life at 6 and 12 months. Objective use data of the web- and smartphone-based PA program were collected. Analytic methods included intention to treat and constrained longitudinal data analyses.

Results

The study sample included 228 participants (n=176, 77.2% females) with a mean age of 62.4 (SD 6.7) years and a mean BMI of 28.2 (SD 4.2) kg/m². Approximately 53.9% (123/228) of the participants were retired. No group differences were found for any baseline variable. At 12 months, the proportion of patients achieving PAG was significantly higher in intervention group than in the control group (81% vs 67% respectively, odds ratio 2.34, 95% CI 1.02-5.38; P=.045). No difference between intervention and control group was found neither in achieving PAG at 6 months nor for sedentary time, weight, and waist circumference at 6 and 12 months. Regarding quality of life, the physical component subscale score was significantly higher at 12 months in the intervention group than in the control group (mean difference: 4.1, 95% CI 1.9-6.3; P<.001). The mean duration use of the program was 7.1 (SD 4.5) months. Attrition rate during the first 2 months was 20.4% (23/113) whereas 39.8% (45/113) of the participants used the program for at least 10 months.

Conclusions

PA increased in both the intervention group and the control group. However, at 12 months, more participants met PAG in the intervention group compared with the controls. This indicates that the web- and smartphone-based program could have maintained PA in the intervention group. In addition, a spa therapy seems to be an ideal time and framework to implement PA education.

Trial Registration

ClinicalTrials.gov NCT02694796; https://clinicaltrials.gov/ct2/show/NCT02694796

Voltage-Induced Bistability of Single Spin-Crossover Molecules in a Two-Dimensional Monolayer

Bistable spin-crossover molecules are particularly interesting for the development of innovative electronic and spintronic devices as they present two spin states that can be controlled by external stimuli. In this paper, we report the voltage-induced switching of the high spin/low spin electronic states of spin-crossover molecules self-assembled in dense 2D networks on Au(111) and Cu(111) by scanning tunneling microscopy at low temperature. On Au(111), voltage pulses lead to the nonlocal switching of the molecules from any─high or low─spin state to the other followed by a spontaneous relaxation toward their initial state within minutes. On the other hand, on Cu(111), single molecules can be addressed at will. They retain their new electronic configuration after a voltage pulse. The memory effect demonstrated on Cu(111) is due to an interplay between long-range intermolecular interaction and molecule/substrate coupling as confirmed by mechanoelastic simulations.

Are 2020’s medical students still suffering from gender stereotypes? An Italian study

Background

Gender medicine is crucial to reduce health inequalities in Europe. Knowledge about medical students' attitudes and beliefs regarding sex and gender is important to improve gender medicine courses. The aim of this study is to evaluate gender awareness and its predictors in Italian medical students.

Methods

During 2020, we performed a cross-sectional study among medical students from the University of Turin, Italy. We used the validated Nijmegen Gender Awareness Scale in Medicine (N-GAMS) to investigate gender sensitivity (GS) and gender role ideology towards patients (GRIP) or doctors (GRID). Multivariable logistic regression model was performed to explore potential predictors of gender awareness.

Results

Globally, 430 participants completed the survey (68.4% were females). The 62.5% of male students had a poor knowledge of gender medicine. GRID score significantly differs between males and females (1.64±0.68 vs 1.51±0.49; p = 0.028). Males had lower GS scores (coefB -0.96, p &lt; 0.05), while students who had a better knowledge on gender medicine (coefB 0.14, p &lt; 0.05) and those who have received good example from tutors (coefB 0.14, p &lt; 0.05) were more gender-sensitive. Older age (coefB 0.04, p &lt; 0.05), a better knowledge on gender medicine (coefB 0.12, p &lt; 0.05) and having had a tutor sensitive to gender issues (coefB 0.13, p &lt; 0.05) were predictors of more stereotyped opinions towards patients. Having had a tutor aware of gender medicine (coefB 0.03, p &lt; 0.05), male sex (coefB 0.12, p &lt; 0.05) and older age (coefB 0.03, p &lt; 0.05) were associated with more stereotypes towards doctors.

Conclusions

Gender stereotypes are still common. During university courses and practical training more attention must be paid to explain that stereotyped gender differences are not scientifically proven and they do not contribute to provide better care. Therefore, the implementation of gender specific teaching throughout elective courses should be seriously considered.

Key messages

Receiving more knowledge and more attention about gender medicine during university education was associated with higher gender stereotypes in our sample of medical students. Interventions in European university education are needed to make gender medicine education more effective in order to reduce gender stereotypes and contribute to better care.

Gender medicine: a cross-sectional survey on knowledge and curriculum among Italian medical students

Introduction

Gender and sex are important predictors of many attitudes and behaviours that have an impact on health and disease. Gender medicine is then a fundamental approach for better quality of care in Europe. Few information is available on Italian medical students and their knowledge about gender medicine. Our study aimed to investigate knowledge about gender medicine in a sample of Italian medical students in order to identify specific knowledge gaps and improve Medicine degree curricula.

Methods

In 2020, an online cross-sectional survey was conducted on 430 medical students of the University of Turin, Italy. Participants filled out a questionnaire consisting of 29 items concerning the areas of knowledge and attitudes regarding gender medicine. Multivariable logistic regression model was performed to explore potential predictors of knowledge among students.

Results

More than 60% of the students knew the correct definition of gender medicine and around 90% of them knew the difference between sex and gender. In total, 58.16% of female students had a good level of knowledge, significantly more than male students (37,5%; p &lt; 0.001); female students also showed a higher mean score compared to male students (respectively 17.96±2.75 vs 16.59±3.20, p &lt; 0.001). Using a multivariate linear regression model, with level of knowledge about gender medicine used as a continuous variable, we found that being female was the only potential predictor of high consideration of gender medicine in patient management.

Conclusions

The results indicate that students have a good knowledge and high regard for gender medicine. Female students seem more aware of the importance of gender medicine and areas of improvement can be identified. Future European physicians must consider gender medicine in order to encourage a patient-tailored approach and to reduce gender gap still existent in current practice.

Key messages

Gender medicine is a fundamental approach to improve quality of care and to reduce gender gap among European patients. Medical students should be more aware and trained about gender and sex differences during clinical practice in order to encourage a patient-tailored medicine.

Pre-exposure prophylaxis' knowledge, attitudes, practices amongst italian men who have sex with men

Background

Pre-exposure prophylaxis (PrEP) is suitable for human immunodeficiency virus (HIV)high-infection-risk people, foremost amongst males who have sex with other males (MSM). This study evaluated knowledge, attitudes and practices regarding PrEP in a sample of Italian MSM, in order to hypothesize strategies to implement PrEP awareness and use.

Methods

An online survey was given to an opportunistic sample of Italian MSM. The questionnaire investigated sexual behaviour, knowledge on HIV and PrEP awareness, attitudes and practices. Univariable and multivariable logistic regressions were conducted to identify possible associations with PrEP knowledge.

Results

A total of 196 MSM completed the survey. Overall data showed very good HIV and safe sexual behaviour knowledge (94.4% of correct answers). Nevertheless, our sample rarely used PrEP because of existing barriers: high therapy price (26.9%)and fear of side effects (23.8%). Only 10.3% of partecipants were informed on HIV and PReP by institutional channels, even less (7.5%) from specialized physicians and general practitioners. The most significant association with PrEP knowledge was having regular HIV-tests (adjusted odds ratio (AdjOR) = 3.16; confidence interval (CI) = 1.06-9.29);

Conclusions

PreP's Knowledge was well established, but PrEP use was not widespread. It is necessary to improve communication on PrEP and to lower existing barriers in order to grant access to PrEP access.

Key messages

Barriers to access PrEP have to be lowered. Healthcare personnel has to be involved in PrEP's benefits communication.

Depression and post-traumatic stress disorder symptoms during the COVID-19 pandemic in Italy

Introduction

Social restrictions imposed by the Italian Government during the COVID-19 emergency might have had a significant impact on mental health. The purpose of this study was to estimate the prevalence of depressive and post-traumatic stress disorder (PTDS) symptoms in a sample of Italian citizens during the first COVID-19 pandemic wave.

Materials and methods

A cross-sectional survey was carried out between April and June 2020 using a snowball sampling. Depressive symptoms were explored through the Patient Heath Questionnaire-2 (PHQ-2), while the post-traumatic stress disorder (PTDS) was investigated through the SPAN (Startle, Physical arousal, Anger, Numbness) questionnaire. Poisson regression models were used to explore the association between the outcomes under study and sociodemographic/housing characteristics.

Results

A total of 10.758 interviews were collected and 7.847 (73%), complete for a minimum set of indicators (age, sex, area of residence), were included in the final analysis. The majority of the respondents were females (71%). Sample mean age was 48.6 years. The prevalence of depressive symptoms was 21.2% and that of PTDS was 43.8%. Symptoms of depression and PTDS significantly diminished across age groups, in particular in people over 70 years compared with people aged 14-29 years (PR 0.65, 95% CI 0.49-0.86). A higher prevalence was found in students compared with retired people, both for depressive symptoms (PR 1.49, 95% CI: 1.05-2.10) and PTDS (PR 1.31, 95% CI: 1.02-1.69).

Conclusions

Prevalence of depressive and PTDS symptoms was high, in particular among younger people and students. That could potentially lead to adverse mental health outcomes in the future, with serious public health consequences. As the pandemic emergency is not solved yet, it is necessary to implement preventive strategies in order to protect the mental well-being of particularly vulnerable subgroups in the population.

Key messages

The prevalence of psychological symptoms was high in this sample during the first wave of COVID-19 pandemic.

The subgroups of the population at higher risk for adverse psychological outcomes were younger people and students.

Energy Intake Evaluation by a Learning Approach Using the Number of Food Portions and Body Weight

An accurate quantification of energy intake is critical; however, under-reporting is frequent. The aim of this study was to develop an indirect statistical method of the total energy intake estimation based on gender, weight, and the number of portions. The energy intake prediction was developed and evaluated for validity using energy expenditure. Subjects with various BMIs were recruited and assigned either in the training or the test group. The mean energy provided by a portion was evaluated by linear regression models from the training group. The absolute values of the error between the energy intake estimation and the energy expenditure measurement were calculated for each subject, by subgroup and for the whole group. The performance of the models was determined using the test dataset. As the number of portions is the only variable used in the model, the error was 26.5%. After adding body weight in the model, the error decreased to 8.8% and 10.8% for the normal-weight women and men, respectively, and 11.7% and 12.8% for the overweight women and men, respectively. The results prove that a statistical approach and knowledge of the usual number of portions and body weight is effective and sufficient to obtain a precise evaluation of energy intake after a simple and brief enquiry.

Thermal Bistability of an Ultrathin Film of Iron(II) Spin-Crossover Molecules Directly Adsorbed on a Metal Surface

Spin-crossover molecules are very attractive compounds to realize multifunctional spintronic devices. Understanding their properties when deposited on metals is therefore crucial for their future rational implementation as ultrathin films in such devices. Using X-ray absorption spectroscopy, we study the thermal transition of the spin-crossover compound Fe^II((3,5-(CH₃)₂Pz)₃BH)₂ from submonolayer to multilayers on a Cu(111) substrate. We determine how the residual fraction of high spin molecules at low temperature, as well as the bistability range and the temperature of switching, depends on the layer thickness. The most spectacular effect is the clear opening of a 35 ± 9 K thermal hysteresis loop for a 3.0 ± 0.7 monolayers thick film. To better understand the role played by the substrate and the dimensionality on the thermal bistability, we have performed Monte Carlo Arrhenius simulations in the framework of a mechanoelastic model that include a molecule-substrate interaction. This model reproduces well the main features observed experimentally and can predict how the spin-crossover transition is modified by the thickness and the substrate interaction.

Robust magnetic anisotropy of a monolayer of hexacoordinate Fe(ii) complexes assembled on Cu(111)

The tris pyrazolyl borate ligand imposes a rigid scaffold around Fe(ii) ensuring a robust magnetic anisotropy when the molecules assembled as monolayers suffer from the dissymmetric environment of the substrate/vacuum interface.

Intraconfigurational Transition due to Surface-Induced Symmetry Breaking in Noncovalently Bonded Molecules

The interaction of molecules with surfaces plays a crucial role in the electronic and chemical properties of supported molecules and needs a comprehensive description of interfacial effects. Here, we unveil the effect of the substrate on the electronic configuration of iron porphyrin molecules on Au(111) and graphene, and we provide a physical picture of the molecule-surface interaction. We show that the frontier orbitals derive from different electronic states depending on the substrate. The origin of this difference comes from molecule-substrate orbital selective coupling caused by reduced symmetry and interaction with the substrate. The weak interaction on graphene keeps a ground state configuration close to the gas phase, while the stronger interaction on gold stabilizes another electronic solution. Our findings reveal the origin of the energy redistribution of molecular states for noncovalently bonded molecules on surfaces.

Direct Observation of the Reduction of a Molecule on Nitrogen Pairs in Doped Graphene

Incorporating functional atomic sites in graphene is essential for realizing advanced two-dimensional materials. Doping graphene with nitrogen offers the opportunity to tune its chemical activity with significant charge redistribution occurring between molecules and substrate. The necessary atomic scale understanding of how this depends on the spatial distribution of dopants, as well as their positions relative to the molecule, can be provided by scanning tunneling microscopy. Here we show that a noncovalently bonded molecule such as CoPc undergoes a variable charge transfer when placed on N-doped graphene; on a nitrogen pair, it undergoes a redox reaction with an integral charge transfer whereas a lower fractional charge transfer occurs over a single nitrogen. Thus, the charge state of molecules can be tuned by suitably tailoring the conformation of dopant atoms.

Vaccination knowledge, attitudes and practices in patients with HIV: a cross-sectional survey

Background

Infectious diseases are more common and severe in patients with HIV, which show different response to vaccines and a diminished protection. It is therefore very important to assess knowledge and attitudes towards vaccination in people with HIV, since precise vaccination coverage and vaccine hesitancy are not well established in this subgroup of patients.

Methods

A sample of 119 patients with HIV completed a cross-sectional survey. Patients were recruited during their routine medical examination at the infectious diseases clinic in Turin. The survey explored these main areas: demographics and history of HIV infection, vaccination history, attitudes towards vaccination, confidence in the public health system, contagion risk and disease seriousness perception. In this preliminary phase descriptive analysis were conducted.

Results

Preliminary data show that mean age of the participants was 49.51 years, 80% were males. The median of HIV infection duration was 10 years, while the median of the lymphocyte count was 762.50 cells/mm3. The disease with the highest vaccination coverage was tetanus (88.7%), considered a serious or very serious disease by 85.6% of the participants, despite low or very low contagion risk perception (84.1%). The disease with the lowest vaccination coverage was Herpes Zoster (7.3%), despite high or very high seriousness perception (70%). Furthermore, 99.1% of the participants showed high or very high confidence toward public health system professionals, and the majority of them (59.5%) stated that vaccines are more useful for the community than for the single person.

Conclusions

Vaccination coverage is still not fully satisfactory regarding diseases considered infrequent or mild. Considering the high level of confidence toward the public health system that has emerged, it is necessary to implement informative and operative strategies about vaccination for European HIV patients, which are particularly at risk regarding infectious diseases.

Key messages

Vaccination coverage and risk perception in HIV patients is not satisfactory for many diseases and an effort to implement informative strategies in Europe is needed. The role of vaccination in preventing infectious diseases in HIV patients should be recognized and strengthened by relying on the high level of confidence toward European public health systems.

Controlling Hydrogen-Transfer Rate in Molecules on Graphene by Tunable Molecular Orbital Levels

Molecular switches are building blocks of potential interest to store binary information, especially when they can be organized in periodic lattices. Among the variety of possible systems, switches based on hydrogen transfer are of special importance because they allow the switching operation to occur without severe conformational change that may interfere with neighboring molecular units. We have studied the excitation process of hydrogen transfer inside porphyrin molecules assembled on a graphene surface, using a low-temperature scanning tunneling microscope. We show that this hydrogen transfer is induced by an electronic resonant tunneling process through the molecular orbitals. Using nitrogen doping of graphene, we tune the rate of hydrogen transfer by shifting the molecular orbital energies owing to the charge transfer at nitrogen dopant sites in the graphene lattice. The control of the switching process allows the storage of information inside a molecular lattice, which is demonstrated by writing an artificial pattern inside a molecular island.

Importance of Epitaxial Strain at a Spin-Crossover Molecule-Metal Interface

Spin-crossover molecules are very appealing for use in multifunctional spintronic devices because of their ability to switch between high-spin and low-spin states with external stimuli such as voltage and light. In actual devices, the molecules are deposited on a substrate, which can modify their properties. However, surprisingly little is known about such molecule-substrate effects. Here we show for the first time, by grazing incidence X-ray diffraction, that an Fe^II spin-crossover molecular layer displays a well-defined epitaxial relationship with a metal substrate. Then we show, by both density functional calculations and a mechanoelastic model, that the resulting epitaxial strain and the related internal pressure can induce a partial spin conversion at low temperatures, which has indeed been observed experimentally. Our results emphasize the importance of substrate-induced spin state transitions and raise the possibility of exploiting them.

How to Measure Sedentary Behavior at Work?

Background: Prolonged sedentary behavior (SB) is associated with increased risk for chronic conditions. A growing number of the workforce is employed in office setting with high occupational exposure to SB. There is a new focus in assessing, understanding and reducing SB in the workplace. There are many subjective (questionnaires) and objective methods (monitoring with wearable devices) available to determine SB. Therefore, we aimed to provide a global understanding on methods currently used for SB assessment at work.

Methods: We carried out a systematic review on methods to measure SB at work. Pubmed, Cochrane, Embase, and Web of Science were searched for peer-reviewed English-language articles published between 1st January 2000 and 17th March 2019.

Results: We included 154 articles: 89 were cross-sectional and 65 were longitudinal studies, for a total of 474,091 participants. SB was assessed by self-reported questionnaires in 91 studies, by wearables devices in also 91 studies, and simultaneously by a questionnaire and wearables devices in 30 studies. Among the 91 studies using wearable devices, 73 studies used only one device, 15 studies used several devices, and three studies used complex physiological systems. Studies exploring SB on a large sample used significantly more only questionnaires and/or one wearable device.

Conclusions: Available questionnaires are the most accessible method for studies on large population with a limited budget. For smaller groups, SB at work can be objectively measured with wearable devices (accelerometers, heart-rate monitors, pressure meters, goniometers, electromyography meters, gas-meters) and the results can be associated and compared with a subjective measure (questionnaire). The number of devices worn can increase the accuracy but make the analysis more complex and time consuming.

Tuning the Electronic and Dynamical Properties of a Molecule by Atom Trapping Chemistry

The ability to trap adatoms with an organic molecule on a surface has been used to obtain a range of molecular functionalities controlled by the choice of the molecular trapping site and local deprotonation. The tetraphenylporphyrin molecule used in this study contains three types of trapping sites: two carbon rings (phenyl and pyrrole) and the center of a macrocycle. Catching a gold adatom on the carbon rings leads to an electronic doping of the molecule, whereas trapping the adatom at the macrocycle center with single deprotonation leads to a molecular rotor and a second deprotonation leads to a molecular jumper. We call "atom trapping chemistry" the control of the structure, electronic, and dynamical properties of a molecule achieved by trapping metallic atoms with a molecule on a surface. In addition to the examples previously described, we show that more complex structures can be envisaged.

A Novel Smartphone Accelerometer Application for Low-Intensity Activity and Energy Expenditure Estimations in Overweight and Obese Adults

Physical inactivity and sedentary behaviors are on the rise worldwide and contribute to the current overweight and obesity scourge. The loss of healthy life style benchmarks and the lack of the need to move make it necessary to provide feedback about physical and sedentary activities in order to promote active ways of life. The aim of this study was to develop a specific function adapted to overweight and obese people to identify four physical activity (PA) categories and to estimate the associated total energy expenditure (TEE). This function used accelerometry data collected from a smartphone to evaluate activity intensity and length, and TEE. The performance of the proposed function was estimated according to two references (Armband® and FitmatePro®) under controlled conditions (CC) for a 1.5-h scenario, and to the Armband® device in free-living conditions (FLC) over a 12-h monitoring period. The experiments were carried out with overweight and obese volunteers: 13 in CC and 27 in FLC. The evaluation differences in time spent in each category were lower than 7% in CC and 6% in FLC, in comparison to the Armband® and FitmatePro® references. The TEE mean gap in absolute value between the function and the two references was 9.3% and 11.5% in CC, and 8.5% according to Armband® in FLC.

The eMouveRecherche application competes with research devices to evaluate energy expenditure, physical activity and still time in free-living conditions

The proliferation of smartphones is creating new opportunities to monitor and interact with human subjects in free-living conditions since smartphones are familiar to large segments of the population and facilitate data collection, transmission and analysis. From accelerometry data collected by smartphones, the present work aims to estimate time spent in different activity categories and the energy expenditure in free-living conditions. Our research encompasses the definition of an energy-saving function (Pred^EE) considering four physical categories of activities (still, light, moderate and vigorous), their duration and metabolic cost (MET). To create an efficient discrimination function, the method consists of classifying accelerometry-transformed signals into categories and of associating each category with corresponding Metabolic Equivalent Tasks. The performance of the Pred^EE function was compared with two previously published functions (f(η,d)aedes,f(η,d)nrjsi), and with two dedicated sensors (Armband® and Actiheart®) in free-living conditions over a 12-h monitoring period using 30 volunteers. Compared to the two previous functions, Pred^EE was the only one able to provide estimations of time spent in each activity category. In relative value, all the activity categories were evaluated similarly to those given by Armband®. Compared to Actiheart®, the function underestimated still activities by 10.1% and overestimated light- and moderate-intensity activities by 7.9% and 4.2%, respectively. The total energy expenditure error produced by Pred^EE compared to Armband® was lower than those given by the two previous functions (5.7% vs. 14.1% and 17.0%). Pred^EE provides the user with an accurate physical activity feedback which should help self-monitoring in free-living conditions.

High-intensity interval training reduces abdominal fat mass in postmenopausal women with type 2 diabetes

AIM

This study compared the effect of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) for 16 weeks on whole-body and abdominal fat mass (FM) in postmenopausal women with type 2 diabetes (T2D).

METHODS

Seventeen women (69±1 years; BMI: 31±1kg.m^-2) were randomly assigned to either a HIIT [60×(8s at 77-85% HR_max, 12s of active recovery)] or MICT (40min at 55-60% of their individual HRR) cycling program for 16 weeks, 2 days/week. Dual-energy X-ray absorptiometry was used to measure whole-body and regional FM content, including abdominal adiposity and visceral adipose tissue. Plasma cholesterol, HDL, LDL, triglycerides, glucose and HbA_1c levels were measured. Levels of nutritional intake and physical activity were evaluated by 7-day self-reports.

RESULTS

Dietary energy (caloric) intake, physical activity level and total body mass did not vary in either group from the beginning to the end of the training intervention. Overall, total FM decreased and total fat-free mass significantly increased over time (by around 2-3%). Total FM reduction at the end of the intervention was not significantly different between groups. However, significant loss of total abdominal (-8.3±2.2%) and visceral (-24.2±7.7%) FM was observed only with HIIT. Time effects were noted for HbA_1c and total cholesterol/HDL ratio.

CONCLUSION

With no concomitant caloric restriction, an HIIT program in postmenopausal women with T2D (twice a week for 16 weeks) appeared to be more effective for reducing central obesity than MICT, and could be proposed as an alternative exercise training program for this population.

Control of Molecule-Metal Interaction by Hydrogen Manipulation in an Organic Molecule

Free-base porphyrin molecules offer appealing options to tune the interaction with their environment via the manipulation of their inner hydrogen atoms and molecular conformation. Using scanning tunneling microscopy we show, through a systematic study, that the molecular conformation, electronic gap, wave function, and molecule-substrate interaction are modified by hydrogen switch or removal. Experimental results in combination with ab initio calculations provide an understanding of the underlying physical process.

Molecular adsorbates as probes of the local properties of doped graphene

Graphene-based sensors are among the most promising of graphene's applications. The ability to signal the presence of molecular species adsorbed on this atomically thin substrate has been explored from electric measurements to light scattering. Here we show that the adsorbed molecules can be used to sense graphene properties. The interaction of porphyrin molecules with nitrogen-doped graphene has been investigated using scanning tunneling microscopy and ab initio calculations. Molecular manipulation was used to reveal the surface below the adsorbed molecules allowing to achieve an atomic-scale measure of the interaction of molecules with doped graphene. The adsorbate's frontier electronic states are downshifted in energy as the molecule approaches the doping site, with largest effect when the molecule sits over the nitrogen dopant. Theoretical calculations showed that, due to graphene's high polarizability, the adsorption of porphyrin induces a charge rearrangement on the substrate similar to the image charges on a metal. This charge polarization is enhanced around nitrogen site, leading to an increased interaction of molecules with their image charges on graphene. Consequently, the molecular states are stabilized and shift to lower energies. These findings reveal the local variation of polarizability induced by nitrogen dopant opening new routes towards the electronic tuning of graphene.

Charge transfer and electronic doping in nitrogen-doped graphene

Understanding the modification of the graphene’s electronic structure upon doping is crucial for enlarging its potential applications. We present a study of nitrogen-doped graphene samples on SiC(000) combining angle-resolved photoelectron spectroscopy, scanning tunneling microscopy and spectroscopy and X-ray photoelectron spectroscopy (XPS). The comparison between tunneling and angle-resolved photoelectron spectra reveals the spatial inhomogeneity of the Dirac energy shift and that a phonon correction has to be applied to the tunneling measurements. XPS data demonstrate the dependence of the N 1s binding energy of graphitic nitrogen on the nitrogen concentration. The measure of the Dirac energy for different nitrogen concentrations reveals that the ratio usually computed between the excess charge brought by the dopants and the dopants’ concentration depends on the latter. This is supported by a tight-binding model considering different values for the potentials on the nitrogen site and on its first neighbors.

Electronic interaction between nitrogen atoms in doped graphene

Many potential applications of graphene require either the possibility of tuning its electronic structure or the addition of reactive sites on its chemically inert basal plane. Among the various strategies proposed to reach these objectives, nitrogen doping, i.e., the incorporation of nitrogen atoms in the carbon lattice, leads in most cases to a globally n-doped material and to the presence of various types of point defects. In this context, the interactions between chemical dopants in graphene have important consequences on the electronic properties of the systems and cannot be neglected when interpreting spectroscopic data or setting up devices. In this report, the structural and electronic properties of complex doping sites in nitrogen-doped graphene have been investigated by means of scanning tunneling microscopy and spectroscopy, supported by density functional theory and tight-binding calculations. In particular, based on combined experimental and simulation works, we have systematically studied the electronic fingerprints of complex doping configurations made of pairs of substitutional nitrogen atoms. Localized bonding states are observed between the Dirac point and the Fermi level in contrast with the unoccupied state associated with single substitutional N atoms. For pyridinic nitrogen sites (i.e., the combination of N atoms with vacancies), a resonant state is observed close to the Dirac energy. This insight into the modifications of electronic structure induced by nitrogen doping in graphene provides us with a fair understanding of complex doping configurations in graphene, as it appears in real samples.

Deficits in egocentric-updating and spatial context memory in a case of developmental amnesia

Patients with developmental amnesia usually suffer from both episodic and spatial memory deficits. DM, a developmental amnesic, was impaired in her ability to process self-motion (i.e., idiothetic) information while her ability to process external stable landmarks (i.e., allothetic) was preserved when no self-motion processing was required. On a naturalistic and incidental episodic task, DM was severely and predictably impaired on both free and cued recall tasks. Interestingly, when cued, she was more impaired at recalling spatial context than factual or temporal information. Theoretical implications of that co-occurrence of deficits and those dissociations are discussed and testable cerebral hypothesis are proposed.

Grain boundaries in graphene on SiC(0001̅) substrate

Grain boundaries in epitaxial graphene on the SiC(0001̅) substrate are studied using scanning tunneling microscopy and spectroscopy. All investigated small-angle grain boundaries show pronounced out-of-plane buckling induced by the strain fields of constituent dislocations. The ensemble of observations determines the critical misorientation angle of buckling transition θc = 19 ± 2°. Periodic structures are found among the flat large-angle grain boundaries. In particular, the observed θ = 33 ± 2° highly ordered grain boundary is assigned to the previously proposed lowest formation energy structural motif composed of a continuous chain of edge-sharing alternating pentagons and heptagons. This periodic grain boundary defect is predicted to exhibit strong valley filtering of charge carriers thus promising the practical realization of all-electric valleytronic devices.

Electronic interaction between nitrogen-doped graphene and porphyrin molecules

The chemical doping of graphene is a promising route to improve the performances of graphene-based devices through enhanced chemical reactivity, catalytic activity, or transport characteristics. Understanding the interaction of molecules with doped graphene at the atomic scale is therefore a leading challenge to be overcome for the development of graphene-based electronics and sensors. Here, we use scanning tunneling microscopy and spectroscopy to study the electronic interaction of pristine and nitrogen-doped graphene with self-assembled tetraphenylporphyrin molecules. We provide an extensive measurement of the electronic structure of single porphyrins on Au(111), thus revealing an electronic decoupling effect of the porphyrins adsorbed on graphene. A tip-induced switching of the inner hydrogen atoms of porphyrins, first identified on Au(111), is observed on graphene, allowing the identification of the molecular conformation of porphyrins in the self-assembled molecular layer. On nitrogen-doped graphene, a local modification of the charge transfer around the nitrogen sites is evidenced via a downshift of the energies of the molecular elecronic states. These data show how the presence of nitrogen atoms in the graphene network modifies the electronic interaction of organic molecules with graphene. These results provide a basic understanding for the exploitation of doped graphene in molecular sensors or nanoelectronics.

Fine mapping of quantitative trait loci underlying sensory meat quality traits in three French beef cattle breeds

Improving the traits that underlie meat quality is a major challenge in the beef industry. The objective of this paper was to detect QTL linked to sensory meat quality traits in 3 French beef cattle breeds. We genotyped 1,059, 1,219, and 947 young bulls and their sires belonging to the Charolais, Limousin, and Blonde d'Aquitaine breeds, respectively, using the Illumina BovineSNP50 BeadChip (Illumina Inc., San Diego, CA). After estimating relevant genetic parameters using VCE software, we performed a linkage disequilibrium and linkage analysis on 4 meat traits: intramuscular fat content, muscle lightness, shear force, and tenderness score. Heritability coefficients largely ranged between 0.10 and 0.24; however, they reached a maximum of 0.44 and 0.50 for intramuscular fat content and tenderness score, respectively, in the Charolais breed. The 2 meat texture traits, shear force and tenderness score, were strongly genetically correlated (-0.91 in the Charolais and Limousin breed and -0.86 in the Blonde d'Aquitaine breed), indicating that they are 2 different measures of approximately the same trait. The genetic correlation between tenderness and intramuscular fat content differed across breeds. Using a significance threshold of 5 × 10(-4) for QTL detection, we found more than 200 significant positions across the 29 autosomal chromosomes for the 4 traits in the Charolais and Blonde d'Aquitaine breeds; in contrast, there were only 78 significant positions in the Limousin breed. Few QTL were common across breeds. We detected QTL for intramuscular fat content located near the myostatin gene in the Charolais and Blonde d'Aquitaine breeds. No mutation in this gene has been reported for the Blonde d'Aquitaine breed; therefore, it suggests that an unknown mutation could be segregating in this breed. We confirmed that, in certain breeds, markers in the calpastatin and calpain 1 gene regions affect tenderness. We also found new QTL as several QTL on chromosome 3 that are significantly associated with meat tenderness in the Blonde d'Aquitaine breed. Overall, these results greatly contribute to the goal of building a panel of markers that can be used to select animals of high meat quality.

Comparison of total energy expenditure assessed by two devices in controlled and free-living conditions

The objective of this study was to evaluate the validity of total energy expenditure (TEE) provided by Actiheart and Armband. Normal-weight adult volunteers wore both devices either for 17 hours in a calorimetric chamber (CC, n = 49) or for 10 days in free-living conditions (FLC) outside the laboratory (n = 41). The two devices and indirect calorimetry or doubly labelled water, respectively, were used to estimate TEE in the CC group and FLC group. In the CC, the relative value of TEE error was not significant (p > 0.05) for Actiheart but significantly different from zero for Armband, showing TEE underestimation (-4.9%, p < 0.0001). However, the mean absolute values of errors were significantly different between Actiheart and Armband: 8.6% and 6.7%, respectively (p = 0.05). Armband was more accurate for estimating TEE during sleeping, rest, recovery periods and sitting-standing. Actiheart provided better estimation during step and walking. In FLC, no significant error in relative value was detected. Nevertheless, Armband produced smaller errors in absolute value than Actiheart (8.6% vs. 12.8%). The distributions of differences were more scattered around the means, suggesting a higher inter-individual variability in TEE estimated by Actiheart than by Armband. Our results show that both monitors are appropriate for estimating TEE. Armband is more effective than Actiheart at the individual level for daily light-intensity activities.

Imaging of photonic modes in an AlN-based photonic crystal probed by an ultra-violet internal light source

The spatial distribution of photon modes confined in a 0D cavity and a 1D W1 waveguide is investigated on AlN-based photonic crystal (PC) membranes by spectrally resolved scanning confocal microscopy in the ultra-violet spectral range. The influence of the fabrication-induced disorder of the PC on the photon modes is analyzed. The cavity modes are shown to be robust with respect to disorder, whereas the 1D modes of the W1 waveguide are localized near its cut-off frequency. Those modifications of the lowest energy photonic modes are compared to simulations of weakly disordered photonic structures.

Long-range ordered nanodomains of grafted electroactive molecules

We demonstrate the capability to build zero and one-dimensional electroactive molecular nanostructures ordered over a macroscopic scale and stable under ambient conditions. To realize these arrays, we use the selective grafting of functionalized thiols (juglon and terthiophene based) on a self-organized metallic template. The nanoscale patterning of the molecular conductance is demonstrated and analyzed by scanning tunneling spectroscopy. Finally, the influence of the nanostructuring on electro-chemical properties is measured, paving the way to an all-bottom-up fabrication of nanostructured templates for nanosciences.

Identification of nitrogen dopants in single-walled carbon nanotubes by scanning tunneling microscopy

Using scanning tunnelling microscopy and spectroscopy, we investigated the atomic and electronic structure of nitrogen-doped single walled carbon nanotubes synthesized by chemical vapor deposition. The insertion of nitrogen in the carbon lattice induces several types of point defects involving different atomic configurations. Spectroscopic measurements on semiconducting nanotubes reveal that these local structures can induce either extended shallow levels or more localized deep levels. In a metallic tube, a single doping site associated with a donor state was observed in the gap at an energy close to that of the first van Hove singularity. Density functional theory calculations reveal that this feature corresponds to a substitutional nitrogen atom in the carbon network.

Directed growth of mixed self-assembled monolayers on a nanostructured template: a step toward the patterning of functional molecular domains

We report on the elaboration of networks of SAM domains. More precisely, we show the feasibility in making arrays of functionalized alkylthiol nanodomains bordered with an alkylthiol matrix. The several step process relies on the replication of a self-organized cobalt array grown on Au(111). The SAM process takes place in solution. The chemical affinity of thiol for gold leads to the selective grafting of molecules on the surface. After having removed the inorganic array, alkylthiol functionalized with a terthiophene unit is grafted in free gold areas. The efficiency of the replication of the initial template depends on the stability of the first SAM. We also investigate electronic tunnel transport through oligothiophene islands with the STM. The variation of the molecular contrast with bias voltage between the two molecular species indicates a potential resonant tunneling mechanism through the orbitals of the aromatic compound.

Protein feeding pattern, casein feeding, or milk-soluble protein feeding did not change the evolution of body composition during a short-term weight loss program

Studies have shown that timing of protein intake, leucine content, and speed of digestion significantly affect postprandial protein utilization. Our aim was to determine if one can spare lean body mass during energy restriction by varying the quality and the timing of protein intake. Obese volunteers followed a 6-wk restricted energy diet. Four groups were compared: casein pulse, casein spread, milk-soluble protein (MSP, = whey) pulse, and MSP spread (n = 10-11 per group). In casein groups, caseins were the only protein source; it was MSP in MSP groups. Proteins were distributed in four meals per day in the proportion 8:80:4:8% in the pulse groups; it was 25:25:25:25% in the spread groups. We measured weight, body composition, nitrogen balance, 3-methylhistidine excretion, perception of hunger, plasma parameters, adipose tissue metabolism, and whole body protein metabolism. Volunteers lost 7.5 ± 0.4 kg of weight, 5.1 ± 0.2 kg of fat, and 2.2 ± 0.2 kg of lean mass, with no difference between groups. In adipose tissue, cell size and mRNA expression of various genes were reduced with no difference between groups. Hunger perception was also never different between groups. In the last week, due to a higher inhibition of protein degradation and despite a lower stimulation of protein synthesis, postprandial balance between whole body protein synthesis and degradation was better with caseins than with MSP. It seems likely that the positive effect of caseins on protein balance occurred only at the end of the experiment.