Role of Reference Frames for a Safe Human-Robot Interaction.

Safety plays a key role in human-robot interactions in collaborative robot (cobot) applications. This paper provides a general procedure to guarantee safe workstations allowing human operations, robot contributions, the dynamical environment, and time-variant objects in a set of collaborative robotic tasks. The proposed methodology focuses on the contribution and the mapping of reference frames. Multiple reference frame representation agents are defined at the same time by considering egocentric, allocentric, and route-centric perspectives. The agents are processed to provide a minimal and effective assessment of the ongoing human-robot interactions. The proposed formulation is based on the generalization and proper synthesis of multiple cooperating reference frame agents at the same time. Accordingly, it is possible to achieve a real-time assessment of the safety-related implications through the implementation and fast calculation of proper safety-related quantitative indices. This allows us to define and promptly regulate the controlling parameters of the involved cobot without velocity limitations that are recognized as the main disadvantage. A set of experiments has been realized and investigated to demonstrate the feasibility and effectiveness of the research by using a seven-DOF anthropomorphic arm in combination with a psychometric test. The acquired results agree with the current literature in terms of the kinematic, position, and velocity aspects; use measurement methods based on tests provided to the operator; and introduce novel features of work cell arranging, including the use of virtual instrumentation. Finally, the associated analytical-topological treatments have enabled the development of a safe and comfortable measure to the human-robot relation with satisfactory experimental results compared to previous research. Nevertheless, the robot posture, human perception, and learning technologies would have to apply research from multidisciplinary fields such as psychology, gesture, communication, and social sciences in order to be prepared for positioning in real-world applications that offer new challenges for cobot applications.

HANDS: an RGB-D dataset of static hand-gestures for human-robot interaction.

The HANDS dataset has been created for human-robot interaction research, and it is composed of spatially and temporally aligned RGB and Depth frames. It contains 12 static single-hand gestures performed with both the right-hand and the left-hand, and 3 static two-hands gestures for a total of 29 unique classes. Five actors (two females and three males) have been acquired performing the gestures, each of them adopting a different background and light conditions. For each actor, 150 RGB frames and their corresponding 150 Depth frames per gesture have been collected, for a total of 2400 RGB frames and 2400 Depth frames per actor. Data has been collected using a Kinect v2 camera intrinsically calibrated to spatially align RGB data to Depth data. The temporal alignment has been performed offline using MATLAB, aligning frames with a maximum temporal distance of 66  ms. This dataset has been used in [1] and it is freely available at http://dx.doi.org/10.17632/ndrczc35bt.1.

A naturalistic study on the relationship among resilient factors, psychiatric symptoms, and psychosocial functioning in a sample of residential patients with psychosis.

OBJECTIVE: Resilience is a multidimensional process of adaptation aimed to overcome stressful or traumatic life experiences; only in the last few years it has been considered as a personal resource in psychosis and schizophrenia. This study aimed to assess the relationship between intrapersonal and interpersonal resilience factors and schizophrenia, particularly whether and how resilience can improve the course of psychotic illness. PATIENTS AND METHODS: In this observational study, all patients recruited had to fulfill the following inclusion criteria: diagnosis of schizophrenia spectrum disorder (Diagnostic and Statistical Manual of Mental Disorders-5); aged between 18 and 65 years; provided written informed consent; to be clinically stable (Clinical Global Impression Scale <3); history of illness ≥5 years; to be compliant with antipsychotic therapy over the last year; and regular submission to periodic monthly psychiatric visits. Patients were evaluated through the following scales: Resilience Scale for Adults (RSA) for resilience; Brief Psychiatric Rating Scale-Anchored version (BPRS-A), Scale for the Assessment of Negative Symptoms (SANS), and Scale for the Assessment of Positive Symptoms (SAPS) for psychotic symptomatology; and Life Skills Profile (LSP) for psychosocial functioning. Statistical analysis was performed by SPSS. Partial correlations were evaluated to assess the relationship between RSA total scores and subscores and BPRS-A, SANS, SAPS, and LSP total scores, removing the common variance among variables. Then, a series of hierarchical multiple linear regression models were used to examine the association between resilience, psychopathology, and psychosocial functioning. RESULTS: A statistically significant negative correlation among intrapersonal resilience factors and BPRS-A total score emerged, predicting psychiatric symptoms severity and explaining approximately 31% of the BPRS-A variance; otherwise, only the interpersonal resilience factors associated with social support were statistically and positively correlated with LSP total score, predicting psychosocial functioning and explaining the 11% of LSP variance. CONCLUSION: The specific contribution that resilience factors may have in predicting the severity of symptoms and the extent of psychosocial functioning emphasizes the importance of personalizing treatment for patients affected by schizophrenia, promoting personal resources, and translating them into better outcomes.

Effects of snake venom proteases on human fibrinogen chains.

BACKGROUND: Proteomic approach is an effective method to study changes in human plasma proteome. Coagulopathies are commonly encountered in victims of viper envenomation which were treated with an administration of immunoglobulin. Unfortunately, this treatment shows significant risk to the patient due to an anaphylactic reaction. Since Echis carinatus Venom (EV) toxins mainly acts both directly and indirectly on fibrinogen, we planned to establish a suitable analysis of its beta (FIBB) e gamma (FIBG) chains. This study will help us to understand the mechanism of envenomation and to find alternative treatments other than the common treatment with the administration of IgG. STUDY DESIGN AND METHODS: We evaluated the EV proteolytic activity on whole human plasma proteome from the blood of an healthy volunteer. Two-dimensional electrophoresis (2-DE) using mini-gel was performed to analyse EV effects on the differents fibrinogen chains. RESULTS: Changes in whole plasma proteome were focused on fibrinogen beta and gamma chains after EV incubation. Protein spots were detected and analyzed using ImageMaster 2D Platinum software. Results were represented as mean +/- standard deviation (mean+/-SD) with p<0.05 as a statistically significant value. 2-DE gel analysis showed that some spots of FIBB disappeared and some spots of FIBG decreased. CONCLUSION: We found that the proteomic approach is a valid method in studying in-depth causes of different diseases, in particular those are involved in coagulopathies linked with proteins like fibrinogen from victims of viper envenomation.

Ultrastructural and biochemical investigations of protein mobilization of Mucuna pruriens (L.) DC. cotyledons and embryo axis.

The mobilization of storage reserves, with particular emphasis on storage proteins of Mucuna pruriens (L.) DC., cotyledons, and embryo was investigated from the ultrastructural and biochemical points of view. Proteins and starch were the two main storage substances in cotyledons, and proteins and lipids were the main ones in the embryo. Embryo protein bodies were smaller and fewer in number than those of cotyledons. Structural and ultrastructural data determined between 24 and 48 h after imbibition and between 48 and 72 h after imbibition, the end of significant embryo and cotyledon protein mobilization, respectively, indicating more precocious storage protein mobilization in the axis than cotyledons. Moreover, storage protein mobilization in embryo and cotyledons occurred before the end of germination. Water soluble proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, producing 29 bands with molecular weights from 14 to 90 KDa. Embryo extract contained more proteins than cotyledon extract, contained seven characteristic bands, and showed a higher variability of the optical density trend than cotyledon.

Relationship between Hpt polymorphisms and serum protein electropherogram.

Serum protein electrophoresis is routinely used to identify pathologies involving dysproteinemia. The electropherogram mainly represents the most abundant serum proteins, one of which is the polymorphic haptoglobin (Hpt), characterized by a molecular heterogeneity with three major phenotypes (Hpt 1-1, 2-1, and 2-2). To improve the interpretation of electropherogram and possibly to extend its applicability, we aimed to explore the relationship between Hpt phenotypes (determined by immunoblotting) and protein profiles. Serum samples were separated by CZE with PROTEIN 6 and high-resolution methods. The PROTEIN 6 analysis showed significant associations between alpha2 zone profiles and Hpt phenotypes (chi-square=154.06, p<0.0001). The high-resolution method indicated significant differences between Hpt 2-2 and Hpt 1-1 peak mobilities, evidenced by receiver operating characteristic analysis, (area under the receiver operating characteristic curve=0.98, p<0.0001, standard error=0.01346, likelihood ratios=21.39), with 98.7% sensitivity, and 95.4% specificity. However, the structural heterogeneity of Hpt 2-1 made it difficult to relate with a particular profile. Thus, we developed an alternative approach that excluded the Hpt 1-1 or Hpt 2-2 phenotypes. This may prove to be a useful technique in clinical applications considering the involvement of Hpt 2-2 or Hpt 1-1 in various pathologies.

Proteomic analysis of the pathophysiological process involved in the antisnake venom effect of Mucuna pruriens extract.

Previously, we reported the antisnake venom properties of a Mucuna pruriens seed extract (MPE) and tested its in vivo efficacy against Echis carinatus venom (EV) in short- (1 injection) and long-term (three weekly injections) treatments. The aim of the present study was to investigate plasma proteome changes associated with MPE treatments and identify proteins responsible for survival of envenomated mice (CHALLENGED mice). Six treatment groups were studied. Three control groups: one saline, one short-term and one long-term MPE treatment. One group received EV alone. Two test groups received EV with either a short-term or long-term MPE treatment (CHALLENGED mice). The plasma from each group was analysed by 2-DE/MALDI-TOF MS. The most significant changes with treatment were: albumin, haptoglobin, fibrinogen, serum amyloid A and serum amyloid P. Most of these changes were explained by EV effects on coagulation, inflammation and haemolysis. However, MPE treatments prevented the EV-induced elevation in HPT. Consequently, HPT levels were similar to controls in the plasma of CHALLENGED mice. The plasma of CHALLENGED mice showed substantial proteomic modifications. This suggests the mechanism of MPE protection involves the activation of counterbalancing processes to compensate for the imbalances caused by EV.

Simultaneous determination of serum concentrations of levodopa, dopamine, 3-O-methyldopa and alpha-methyldopa by HPLC.

Levodopa is the medication of choice for Parkinson's disease. The biological complexity of levodopa and of its main derivatives makes their determination important in the clinical field. The aim of this study was to develop an HPLC method for the simultaneous determination of serum concentrations of levodopa, dopamine, 3-O-methyldopa and alpha-methyldopa. We compared UV and fluorimetric detection of native and derivatised compounds. Though less sensitive than other methods, UV detection is important to exclude naturally fluorescent, interfering substances. Fluorimetric detection of derivatised compounds is more sensitive than UV detection. Since 3-O-methyldopa does not react with the derivatising agent 1,2-diphenylethylenediamine, it cannot be detected. For simultaneous determination of the four compounds after pharmacological treatment of patients we therefore advise fluorimetric detection of the native compound.

Biosynthesis of vitamin C by yeast leads to increased stress resistance.

BACKGROUND: In industrial large scale bio-reactions micro-organisms are generally exposed to a variety of environmental stresses, which might be detrimental for growth and productivity. Reactive oxygen species (ROS) play a key role among the common stress factors--directly--through incomplete reduction of O(2) during respiration, or indirectly--caused by other stressing factors. Vitamin C or L-ascorbic acid acts as a scavenger of ROS, thereby potentially protecting cells from harmful oxidative products. While most eukaryotes synthesize ascorbic acid, yeast cells produce erythro-ascorbic acid instead. The actual importance of this antioxidant substance for the yeast is still a subject of scientific debate. METHODOLOGY/PRINCIPAL FINDINGS: We set out to enable Saccharomyces cerevisiae cells to produce ascorbic acid intracellularly to protect the cells from detrimental effects of environmental stresses. We report for the first time the biosynthesis of L-ascorbic acid from D-glucose by metabolically engineered yeast cells. The amount of L-ascorbic acid produced leads to an improved robustness of the recombinant cells when they are subjected to stress conditions as often met during industrial fermentations. Not only resistance against oxidative agents as H(2)O(2) is increased, but also the tolerance to low pH and weak organic acids at low pH is increased. CONCLUSIONS/SIGNIFICANCE: This platform provides a new tool whose commercial applications may have a substantial impact on bio-industrial production of Vitamin C. Furthermore, we propose S. cerevisiae cells endogenously producing vitamin C as a cellular model to study the genesis/protection of ROS as well as genotoxicity.

Structural characterization of the N-glycans of gpMuc from Mucuna pruriens seeds.

Mucuna pruriens seeds are used in some countries as a human prophylactic oral anti-snake remedy. Aqueous extracts of M. pruriens seeds possess in vivo activity against cobra and viper venoms, and protect mice against Echis carinatus venom. It was recently demonstrated that the seed immunogen generating the antibody that cross-reacts with the venom proteins is a multiform glycoprotein (gpMuc), and the immunogenic properties of gpMuc seemed to mainly reside in its glycan chains. In the present study, gpMuc was found to contain only N-glycans. Part of the N-glycans could be released with peptide-(N (4)-(N-acetyl-beta -glucosaminyl)asparagine amidase F (PNGase F-sensitive N-glycans); the PNGase F-resistant N-glycans were PNGase A-sensitive. The oligosaccharides released were analyzed by a combination of MALDI-TOF mass spectrometry, HPLC profiling of 2-aminobenzamide-labelled derivatives and (1)H NMR spectroscopy. The PNGase F-sensitive N-glycans comprised a mixture of oligomannose-type structures ranging from Man(5)GlcNAc(2) to Man(9)GlcNAc(2), and two xylosylated structures, Xyl(1)Man(3)GlcNAc(2) and Xyl(1)Man(4)GlcNAc(2). The PNGase A-sensitive N-glycans, containing (alpha 1-3)-linked fucose, were identified as Fuc(1)Xyl(1)Man(2)GlcNAc(2) and Fuc(1)Xyl(1)Man(3)GlcNAc(2). In view of the determined N-glycan ensemble, the immunoreactivity of gpMuc was ascribed to the presence of core (beta 1-2)-linked xylose- and core alpha (1-3)-linked fucose-modified N-glycan chains.

Antidiabetic oligocyclitols in seeds of Mucuna pruriens.

Using a combination of chromatographic and NMR techniques, the presence of D-chiro-inositol and its two galacto-derivatives is demonstrated in Mucuna pruriens seeds. The quantities detected explain the well-established antiglycaemic effect of Mucuna pruriens seeds.

Protection of Mucuna pruriens seeds against Echis carinatus venom is exerted through a multiform glycoprotein whose oligosaccharide chains are functional in this role.

In a previous paper we demonstrated that extracts of Mucuna pruriens seeds (MPE) protect mice against Echis carinatus venom (EV) by an immunological mechanism. In this paper we demonstrate that the MPE immunogen generating the antibody that cross-reacts with the venom proteins is a multiform glycoprotein (gpMuc) whose immunogenic properties mainly reside in its glycan-chains. The glycoprotein was purified from the protein extract of M. pruriens seeds using Concanavalin A affinity chromatography. Using 2-D gel electrophoresis it separated into seven isoforms having MWs in the range from 20.3 to 28.7 kDa and pIs from 4.8 to 6.5. N-terminal sequencing of these spots revealed close similarity since all of them contained the consensus sequence DDREPV-DT found in soybean Kunitz-type trypsin inhibitor. We suggest that gpMuc contains both N- and O-glycans. Mild alkaline treatment but not PNGase F led to loss of reactivity, indicating that O-glycans are probably involved in the antigenicity of gpMuc.

Capillary electrophoresis in diagnosis and monitoring of adenosine deaminase deficiency.

BACKGROUND: The diagnosis and monitoring of severe combined immunodeficiency disease (SCID) attributable to adenosine deaminase (ADA) deficiency requires measurements of ADA, purine nucleoside phosphorylase (PNP), and S-adenosyl-L-homocysteine-hydrolase (SAHH) activity and of deoxyadenosine metabolites. We developed capillary electrophoresis (CE) methods for the detection of key diagnostic metabolites and evaluation of enzyme activities. METHODS: Deoxyadenosine metabolites were separated in 30 mmol/L sodium borate-10 mmol/L sodium dodecyl sulfate (pH 9.80) at 25 degrees C on a 60-cm uncoated capillary. For determination of enzyme activities, substrate-product separation and measurements were carried out in 20 mmol/L sodium borate (pH 10.00) at 25 degrees C on a 42-cm uncoated capillary. RESULTS: Deoxynucleotides and deoxyadenosine were readily detectable in erythrocytes and urine, respectively. Both methods were linear in the range 2-500 micro mol/L (r >0.99). Intra- and interassay CV were <4%. Enzyme activities were linear with respect to sample amounts in the incubation mixture and to incubation time (r >0.99 for both). In erythrocytes from healthy individuals, mean (SD) ADA activity was 5619 (2584) nmol/s per liter of packed cells. In erythrocytes of SCID patients at diagnosis, ADA activity was 56.9 (48.3) nmol/s per liter of packed cells; SAHH activity was also much reduced. PNP activity was similar in patients and controls. CONCLUSIONS: CE can be used to test ADA deficiency and enables rapid assessment of ADA expression in hematopoietic cells of SCID patients during therapy.

Proteins from Mucuna pruriens and enzymes from Echis carinatus venom: characterization and cross-reactions.

Mucuna pruriens seeds have been widely used against snakebite in traditional medicine. The antivenin property of a water extract of seeds was assessed in vivo in mice. The serum of mice treated with extract was tested for its immunological properties. Two proteins of Echis carinatus venom with apparent molecular masses of 25 and 16 kDa were detected by Western blot analysis carried out using IgG of mice immunized with extract or its partially purified protein fractions. By enzymatic in-gel digestion and electrospray ionization-mass spectrometry/mass spectrometry analysis of immunoreactive venom proteins, phospholipase A(2,) the most toxic enzyme of snake venom, was identified. These results demonstrate that the observed antivenin activity has an immune mechanism. Antibodies of mice treated with non-lethal doses of venom reacted against some proteins of M. pruriens extract. Proteins of E. carinatus venom and M. pruriens extract have at least one epitope in common as confirmed by immunodiffusion assay.