Resting-state connectivity and functional specialization in human medial parieto-occipital cortex

According to recent models of visuo-spatial processing, the medial parieto-occipital cortex is a crucial node of the dorsal visual stream. Evidence from neurophysiological studies in monkeys has indicated that the parieto-occipital sulcus (POS) contains three functionally and cytoarchitectonically distinct areas: the visual area V6 in the fundus of the POS, and the visuo-motor areas V6Av and V6Ad in a progressively dorsal and anterior location with respect to V6. Besides different topographical organization, cytoarchitectonics, and functional properties, these three monkey areas can also be distinguished based on their patterns of cortico-cortical connections. Thanks to wide-field retinotopic mapping, areas V6 and V6Av have been also mapped in the human brain. Here, using a combined approach of resting-state functional connectivity and task-evoked activity by fMRI, we identified a new region in the anterior POS showing a pattern of functional properties and cortical connections that suggests a homology with the monkey area V6Ad. In addition, we observed distinct patterns of cortical connections associated with the human V6 and V6Av which are remarkably consistent with those showed by the anatomical tracing studies in the corresponding monkey areas. Consistent with recent models on visuo-spatial processing, our findings demonstrate a gradient of functional specialization and cortical connections within the human POS, with more posterior regions primarily dedicated to the analysis of visual attributes useful for spatial navigation and more anterior regions primarily dedicated to analyses of spatial information relevant for goal-directed action

Rapid, 5 min, low temperature aqueous platinization for plastic substrates for dye-sensitized solar cells

This paper reports a rapid (5 min), low temperature (120 �C) method to platinize the counter electrodes of dye-sensitized solar cell (DSC) devices. This new method uses aqueous solutions and is based on chemical bath deposition of an activating Pd layer followed by Pt only using H2 gas as the reductant. This method has been tested on flexible, plastic substrates (indium tin oxide-coated polyethylene terephthalate or polyethylene naphthalate, ITO-PET or ITO-PEN, respectively). We report device efficiencies up to 7.2% on ITO-PET which is comparable to devices made using high temperature (400 �C) processing on rigid, fluoride-doped tin oxide (FTO) glass counter electrodes. The method is scalable and suitable for continuous roll-to-roll production

Expansion dynamics of a dipolar Bose-Einstein condensate

Our recent measurements on the expansion of a chromium dipolar condensate after release from an optical trapping potential are in good agreement with an exact solution of the hydrodynamic equations for dipolar Bose gases. We report here the theoretical method used to interpret the measurement data as well as more details of the experiment and its analysis. The theory reported here is a tool for the investigation of different dynamical situations in time-dependent harmonic traps.Comment: 12 pages. Submitted to PR

ACUTE STRESS AND TRAUMA AT WORK: PREVENTION AND RISK MANAGEMENT IN THE BANKING SECTOR

Background Relevance of the topic and the necessity for scientific investigation Robberies at the bank branches are potentially traumatic events. Many bank employees experiencing a robbery in their workplace suffer important negative consequences as numerous clinical symptoms of post-traumatic stress, worse physical health, impaired productivity and intention to leave their job, both immediately and up to six months after bank robbery. Despite decreasing in frequency, there is an ongoing risk in the bank branches: such events are difficult to predict, and primary intervention strategies may not completely eliminate the risk. Motives for choosing a particular topic Although bank robberies are potentially traumatic event, little is known about the psychological sequelae of those involved. Post-traumatic stress disorder (PTSD) literature has largely focused on victims of specific traumas, such as sexual violence, natural disaster, and military combat. PTSD in the occupational context is still under-investigated, and research mainly concerns specific occupational groups as emergency service personnel, police officers, firefighters, and health care workers. Studies concerning the psychological consequences of bank robberies are limited, mostly based on convenience samples, and vary in outcomes measures and design substantially, thus making comparisons difficult. \u2003 Research problem and why it is worthwhile studying Since only a minority of subjects experiencing such event in the workplace develop long-term clinically important symptoms and functional impairment, understanding the antecedents of occupational PTSD is a key goal of research. A better understanding of risk factors associated to post-traumatic stress reactions may improve early treatment and preventive intervention, thus reducing PTSD onset and worsening of symptoms. Research objectives The study has three main objectives. The first aim is to evaluate the impact of bank robbery on employees psychological well-being, thus investigating post-traumatic stress reactions. The second one is to better understand risk factors associated to the onset of post-traumatic symptomatology. Consequently, the third aim is to inform the development of new interventions and risk management strategies. Research methodology Nine hundred twenty-four employees of a primary Italian bank group, victims of 238 different robberies, voluntarily joined an employer-sponsored post-robbery support program: - a structured and collective support interview (i.e. psychological debriefing) was conducted with robbery victims within 7-15 days after the event (T1) at the bank branch. A self-reported questionnaire collected socio-demographic information, number of bank robberies occurred during participants\u2019 working life, detailed description of the last robbery with closed and open-ended questions, assessment of post-traumatic stress reaction (Impact of Event Scale); - a follow-up psychological assessment (through structured individual interviews) was conducted 45 days after the first session (T2). Interview investigated victims\u2019 general health conditions and self-reported trajectory of post-traumatic symptoms after robbery, victims\u2019 evaluation of the intervention, assessment of post-traumatic stress reaction (Impact of Event Scale). To accomplish with our objectives, the following statistical analysis were adopted: - Absolute and relative frequencies or means and standard deviations, \u3c72 and one-way ANOVA for categorical or continuous variables respectively. - Logistic and linear multilevel regression to estimate the impact of predictive values on post-traumatic symptoms: random intercept mixed-effect regression models to account for subjects\u2019 clustering within robberies. Three hierarchical models were adopted (Model 1: pre-trauma risk factors; Model 2: peri-trauma risk factors; Model 3: subjective perception and reaction to robberies). - Residual pseudo-likelihood test (H0: \u3c3 2 = 0) to assess the significance of unmeasured robbery- related factors; latent variable threshold model approach for the calculation of the variance partition coefficient. Results The final sample consisted in 595 subjects, victims of 238 different robberies. Correlates of early post-robbery reactions were age, being female, being cashier, geographical region, perception of robbers as out of control; after including feelings of fear, terror and hopelessness during the robbery, all the other variables lost statistical significance. IES scores decreased during the follow-up ( 06T1-T2=15.76; p34, a cut-off suggestive of Post-traumatic stress disorder (PTSD). In the multivariable model, age, being female, being cashier, presence of arms, being injured, were associated with PTSD diagnosis. After including early subjective reaction, IES score at T1 was the strongest predictor. Unmeasured robbery-related factors explained a significant portion (24%) of IES variance at T1 after excluding small groups (number of colleagues <5). Limitations Possible selection bias due to the voluntary participation into the intervention program cannot be excluded. Information on non-occupational traumatic events occurred in subjects\u2019 life time and pre-existent psychiatric disorders, as well as perceived support after the event, could not be collected. Assessment of post-traumatic stress symptoms relied on self-report measure without a thorough clinical examination; thus, Impact of Event Scale did not include all criteria for Post-traumatic stress disorder stated by recent DSM-V. Originality of the study The study gives an original contribution to the existing literature of psychological sequelae following bank robbery: to date, this is the longitudinal study with the largest sample assessing prevalence and predictors of post-traumatic stress symptoms; logistic and linear multilevel regression provided a valuable understanding of risk factors; furthermore, no studies had previous investigated the role of group factor in the aftermath of post-traumatic reaction following bank robbery or acute stress at work. Conclusion/Practical implication Our findings showed that bank robbery is a potential traumatizing event associated with both immediate and long-term posttraumatic stress symptoms. Results suggested the weight of subjective variables, such as personal perception of robbery severity and early emotional reaction, in identifying persons at higher risk to develop PTSD. Our findings may help management and prevention of acute stress and trauma in the banking sector, contributing to post-traumatic stress literature. Finally, group factors, an often overlooked dimension in post-traumatic stress literature, might affect the risk of PTSD, thus encouraging further research

Atom interferometry gravity-gradiometer for the determination of the Newtonian gravitational constant G

We developed a gravity-gradiometer based on atom interferometry for the determination of the Newtonian gravitational constant \textit{G}. The apparatus, combining a Rb fountain, Raman interferometry and a juggling scheme for fast launch of two atomic clouds, was specifically designed to reduce possible systematic effects. We present instrument performances and show that the sensor is able to detect the gravitational field induced by source masses. A discussion of projected accuracy for \textit{G} measurement using this new scheme shows that the results of the experiment will be significant to discriminate between previous inconsistent values.Comment: 9 pages,9 figures, Submitte

Three-dimensional eye position signals shape both peripersonal space and arm movement activity in the medial posterior parietal cortex

Research conducted over the last decades has established that the medial part of posterior parietal cortex (PPC) is crucial for controlling visually guided actions in human and non-human primates. Within this cortical sector there is area V6A, a crucial node of the parietofrontal network involved in arm movement control in both monkeys and humans. However, the encoding of action-in-depth by V6A cells had been not studied till recently. Recent neurophysiological studies show the existence in V6A neurons of signals related to the distance of targets from the eyes. These signals are integrated, often at the level of single cells, with information about the direction of gaze, thus encoding spatial location in 3D space. Moreover, 3D eye position signals seem to be further exploited at two additional levels of neural processing: (a) in determining whether targets are located in the peripersonal space or not, and (b) in shaping the spatial tuning of arm movement related activity toward reachable targets. These findings are in line with studies in putative homolog regions in humans and together point to a role of medial PPC in encoding both the vergence angle of the eyes and peripersonal space. Besides its role in spatial encoding also in depth, several findings demonstrate the involvement of this cortical sector in non-spatial processes

Crossing Over from Attractive to Repulsive Interactions in a Tunneling Bosonic Josephson Junction

We explore the interplay between tunneling and interatomic interactions in the dynamics of a bosonic Josephson junction. We tune the scattering length of an atomic $^{39}$K Bose-Einstein condensate confined in a double-well trap to investigate regimes inaccessible to other superconducting or superfluid systems. In the limit of small-amplitude oscillations, we study the transition from Rabi to plasma oscillations by crossing over from attractive to repulsive interatomic interactions. We observe a critical slowing down in the oscillation frequency by increasing the strength of an attractive interaction up to the point of a quantum phase transition. With sufficiently large initial oscillation amplitude and repulsive interactions the system enters the macroscopic quantum self-trapping regime, where we observe coherent undamped oscillations with a self-sustained average imbalance of the relative well population. The exquisite agreement between theory and experiments enables the observation of a broad range of many body coherent dynamical regimes driven by tunable tunneling energy, interactions and external forces, with applications spanning from atomtronics to quantum metrology.Comment: 10 pages, 8 figures, supplemental materials are include

Decoding information for grasping from the macaque dorsomedial visual stream

Neurodecoders have been developed by researchers mostly to control neuroprosthetic devices, but also to shed new light on neural functions. In this study, we show that signals representing grip configurations can be reliably decoded from neural data acquired from area V6A of the monkey medial posterior parietal cortex. Two Macaca fascicularis monkeys were trained to perform an instructed-delay reach-to-grasp task in the dark and in the light toward objects of different shapes. Population neural activity was extracted at various time intervals on vision of the objects, the delay before movement, and grasp execution. This activity was used to train and validate a Bayes classifier used for decoding objects and grip types. Recognition rates were well over chance level for all the epochs analyzed in this study. Furthermore, we detected slightly different decoding accuracies, depending on the task's visual condition. Generalization analysis was performed by training and testing the system during different time intervals. This analysis demonstrated that a change of code occurred during the course of the task. Our classifier was able to discriminate grasp types fairly well in advance with respect to grasping onset. This feature might be important when the timing is critical to send signals to external devices before the movement start. Our results suggest that the neural signals from the dorsomedial visual pathway can be a good substrate to feed neural prostheses for prehensile actions