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Robotic solutions for delivery tasks in urban and unstructured areas have represented a solid and considerable field of research in recent years. The aim of the proposed paper is to present the technical feasibility and usability of a robotic solution able to carry items from outdoor areas up to the user’s apartment and vice-versa. The proposed solution is based on three heterogeneous mobile platforms, working in three different environments (domestic, condominium, outdoor), able to cooperate among themselves and with other machines in the framework (i.e. the elevator of the condominium). The evaluation was performed in realistic environments involving 30 end-users.

Since 2013, the regional network of transplantation centers "LAZIO TRANSPLANT" have adopted a new, mixed system for the allocation of liver grafts.The organs from donors aged 65 are assigned to patients with higher Model for End-stage Liver Disease (MELD) scores on a common regional waiting list, whereas those from donors aged65 are allocated to patients with higher MELD scores on a specific local waiting list (LWL) at each center, on a rotational basis.The new mixed allocation model grants a more rational allocation of the "standard" organs to the patients with the actual worst MELD score in the entire region, avoiding the possibility that a patient in relatively better clinical condition might be transplanted before a more severely ill patient on another center's waiting list. Nonstandard organs, presenting slightly increased transplant risks, are still allocated on a rotational basis among the different transplant centers, ensuring them the possibility to select, on the basis of a global clinical risk evaluation, those patients in their LWL whose MELD score would not grant any possibility to compete for the "standard" organ allocation.The application of the new model had no negative impact on the overall number of transplants performed or on the global list-satisfaction percentages, but has slightly improved the cumulative mortality of the patients in the waiting list, granting to the clinically worst patients a prompt graft allocation, independent of the local center belonging.

Purpose: Despite results of randomized trials that support adjuvant radiation therapy (RT) after radical prostatectomy (RP) for prostate cancer with adverse pathologic features (APF), many clinicians favor selective use of salvage RT. This survey was conducted to evaluate the beliefs and practices of radiation oncologists (RO) and urologists (U) regarding RT after RP. Methods and Materials: We designed a Web-based survey of post-RP RT beliefs and policies. Survey invitations were e-mailed to a list of 926 RO and 591 U. APF were defined as extracapsular extension, seminal vesicle invasion, or positive surgical margin. Differences between U and RO in adjuvant RT recommendations were evaluated by comparative statistics. Multivariate analyses were performed to evaluate factors predictive of adjuvant RT recommendation. Results: Analyzable surveys were completed by 218 RO and 92 U (overallresponse rate, 20%). Adjuvant RT was recommended based on APF by 68% of respondents (78% RO, 44% U, p

Peccioli, a small medieval town in Italy, became one of the first places in the world where a robot was used (not demonstrated) to carry out a public service in the urban environment (from 15 June 2010 to 7 August 2010). Thirty-five real users accepted to trash their domestic waste using the robot DustCart, a mobile robot designed to collect, transport, and discharge rubbish bags in complete autonomy. During the testing period, the robot safely traveled along the public streets of Peccioli, carrying out its daily service and sharing the urban environment with the passers-by, bicycles, and cars, without causing any problems.

In recent years, advances and improvements in engineering and robotics have in part been due to strengthened interactions with the biological sciences. Robots that mimic the complexity and adaptability of biological systems have become a central goal in research and development in robotics. Usually, such a collaboration is addressed to a 2-fold perspective of (i) setting up anthropomorphic platforms as test beds for studies in neuroscience and (ii) promoting new mechatronic and robotic technologies for the development of bio-inspired or humanoid high-performance robotic platforms. This paper provides a brief overview of recent studies on sensorimotor coordination in human motor control and proposes a novel paradigm of adaptive learning for sensorimotor control, based on a multi-network high-level control architecture. The proposed neurobiologically inspired model has been applied to a robotic platform, purposely designed to provide anthropomorphic solutions to neuroscientific requirements. The goal of thi...

Mercury (Hg) in water partially occurs in the form of dissolved atomic vapor, the so-called Dissolved Gaseous Mercury (DGM). DGM can range from 2.5 to 25% of Total Hg (THg). DGM plays an important role in the Hg transfer through the air-water interface. The presented device measures the DGM concentration with the limit of detection 0.05 ng/L in the sample of water (250 mL) taken from a maximum depth of 300 m (limit is imposed by the anodized aluminum watertight sampling cylinder strength and acceptable pressure at the input of the internal solenoid valves). A full process cycle, made-up of sampling, measuring and restoring macro-stages, needs about 20 minutes to be completed and the DGM concentration values are immediately transmitted out for user analysis. Continuous automatic cycle processes can be executed since intra/inter contaminations are carefully avoided. The device is mounted on board of the “V-FIDES” Autonomous Underwater Vehicle (AUV)1 also equipped with a multi-parametric probe measuring physical sea water parameters (pH, salinity, oxygen, etc.).

This study retrospectively evaluated two groups of pregnant women. Group A women (n=1,338) were universally screened for gestational diabetes mellitus (GDM) and GDM patients were intensively treated. In Group B (n=4,035), screening was performed only in women at high risk for GDM and treatment was conventional. This study confirms the validity of a cost-effective screening program for the diagnosis of GDM and that selective screening may be an option only in a situation where healthcare resources are very scarce and/or universal screening of any kind is not feasible. Once the diagnosis of GDM has been made, metabolic management with an intensive approach is important to reduce maternal and fetal morbidity. Diagnosis of GDM and intensive treatment represent a cost for the public health system, but permit a significant monetary savings in terms of costs linked to maternal and neonatal morbidity.

Technological advances in the robotic and ICT fields represent an effective solution to address specific societal problems to support ageing and independent life. One of the key factors for these technologies is that they have to be socially acceptable and believable to the end-users. This paper aimed to present some technological aspects that have been faced to develop the Robot-Era system, a multi-robotic system that is able to act in a socially believable way in the environments daily inhabited by humans, such as urban areas, buildings and homes. In particular, this paper focuses on two services—shopping delivery and garbage collection—showing preliminary results on experiments conducted with 35 elderly people. The analysis adopts an end-user-oriented perspective, considering some of the main attributes of acceptability: usability, attitude, anxiety, trust and quality of life.

A research work on the interaction control of a cable-actuated robot arm, the Dexter arm, is presented in this paper. Firstly, general considerations on the cable-actuated structures and their application potential are provided and then the Dexter structure peculiarities are accurately analyzed in order to develop proper control solutions. Starting from the analysis of the limitations of the compliance control schemes in Cartesian space and in joint space, previously implemented and experimentally validated on the Dexter arm, a novel control strategy, named impedance-compliance controller, is developed. The proposed control strategy tries to combine the benefits of a compliance control scheme in Cartesian space with the benefits of an impedance control scheme in the operational space by compensating the dynamics of the sole proximal joints. The impedance-compliance controller is capable to achieve accurate smooth motions while guaranteeing functional control of the whole structure, even though a greater computational complexity is required The last section of the paper, dedicated to the experimental results, points out the differences with the previously experimented control solutions anti provides some proofs of the increased Dexter functionality.

This paper presents a research work on compliant control of an anthropomorphic robot arm used as a 'personal robot', for assistance to humans in different aspects of their everyday life. In personal applications of robotics, human-robot interaction represents a critical factor for a robot design and introduces strict requirements on its behavior and control, which has to ensure safety and effectiveness. In this work, the problem of controlling the Dexter anthropomorphic robot arm with variable compliance has been investigated, not only to ensure safety in the interaction with humans, but especially to increase the robot functionality in tasks of physical interaction, performed in co-operation with humans. Two different control schemes have been formulated and implemented on the peculiar structure of the robotic arm, so as to compare their performance through experimental trials. Both schemes aim at realising a self-controlled compliant behavior without using information from force/torque sensors. The experimental comparison outlines how the performance of the two control systems are inverted with respect to the theoretical considerations, based on the classical control theory, on their accuracy and effectiveness. The paper firstly describes the two implemented control systems; then, the performance of the two controllers in the experimental trials are shown and compared, and the functional compliance of the better one is graphically demonstrated.

This paper investigates the problem of controlling an anthropomorphic robot arm with autonomously variable compliance in order to ensure safety in the interaction with humans and, above all, to increase the robot functionality in tasks of physical interaction, performed in co-operation with humans. The research work aims at applications in service robotics where the robot arm is used as a 'personal robot', for assistance to humans in different aspects of their everyday life. In personal applications of robotics, human-robot interaction represents a critical factor for the design of the robot and introduces strict requirements on its behavior and control, which has to ensure safety and effectiveness. Two different compliant control schemes have been developed for the peculiar structure of the Dexter robot arm, an anthropomorphic 8 d.o.f. manipulator, and their performances have been comparatively evaluated through experimental trials. The comparative evaluation of the two control schemes, through the analysis of their different advantages and disadvantages, points out an overall better performance of the compliant control scheme in the joint space, relatively to the management of the mechanics of the robotic system. So, it emerges how the performances of the two control systems are inverted with respect to the theoretical considerations on their accuracy and effectiveness, that could be done on the basis of the classical control theory. After a brief description of the control models, the paper focuses on the experimental sessions aimed at verifying the level of accuracy, affordability, functionality and safety of the implemented control systems.

The research in the field of Advanced Robotics is turning its attention more and more to the Man and his assistance, by developing systems such as service robots, personal robots, and even humanoid robots. Interaction control of such robot manipulators is of paramount importance for an effective execution of manipulation and tracking and, over all, for a safe and effective interaction with the humans. This paper concerns with the problem of the control of an 8 degree of freedom anthropomorphic arm, named DEXTER, mounted on the mobile platform of the MOVAID System, a robotic system for household personal assistance. The goal is to realize a compliant control for this manipulator in tasks of assistance to disabled and elderly people. On the basis of the control theory applied to Industrial Robotics, a specific compliant control solution has been developed for the DEXTER peculiar mechanical structure and actuation system, which cause a coupled joint configuration. The solution provides the capability of regulating the robot compliance according to the level of stiffness of the interaction environment. The paper describes the theoretical model of the control system, the implementation on the MOVAID platform and the experimental results in the execution of a set of demonstration tasks.

To assess the clinical outcome of epithelial ovarian cancer patients who developed an apparently isolated lymph node recurrence after primary therapy.The authors retrospectively assessed 69 patients with epithelial ovarian cancer who were clinically or pathologically free of disease after primary therapy and who subsequently developed an apparently isolated lymph node recurrence. The median follow-up of survivors was 74.5 months.Median age was 58 years, FIGO stage was III-IV in 52 (75%) patients, residual disease after primary surgery was1 cm in 36 (52%), first-line chemotherapy consisted of paclitaxel-/platinum-based chemotherapy in 44 (64%), time to recurrence was12 months in 43 (62%), recurrence was pelvic and/or para-aortic in 41 (59%), and treatment at recurrence consisted of chemotherapy alone in 44 (64%), surgery plus chemotherapy in 22 (32%), surgery alone in one patient, surgery plus irradiation in one, and irradiation alone in one patient. Survival after recurrence was significantly related to the type of treatment (chemotherapy alone versus surgery plus chemotherapy, median: 20.8 months versus not reached, p=0.0002), and patient age (58 versus58 years, median: 26.8 versus 44.0 months, p=0.02). Overall survival was significantly related to the type of treatment (chemotherapy alone versus surgery plus chemotherapy, median: 45.4 months versus not reached, p=0.0001), patient age (58 versus58 years, median: 45.4 versus 62.9 months, p=0.03) and time to recurrence (12 months versus12 months, median: 45.4 versus 66.9 months, p=0.01). Cox model showed that treatment at recurrence was the strongest independent prognostic variable for both survival after recurrence (hazard ratio [HR]=0.277, p=0.0003) and overall survival (HR=0.249, p=0.0002).Patients who underwent surgery plus chemotherapy had a 72% reduction in the risk of death after recurrence and a 75% reduction in the risk of death after initial diagnosis when compared with those treated with chemotherapy alone. Secondary cytoreductive surgery appears to be able to prolong survival in epithelial ovarian cancer patients with apparently isolated lymph node recurrence.

The aim of this paper was to assess hypersensitivity reactions in 69 patients who received carboplatin (CBDCA) retreatment for recurrent ovarian cancer. Hypersensitivity reactions developed in 15 (21.7%) patients and occurred during the second cycle of retreatment in 13 (86.7%) of them. Reactions consisted of skin rash, flushing, itching, or abdominal cramping in eight (53.3%) and severe respiratory or cardiovascular events in seven patients (46.7%). One patient had a chest pain, without any other symptoms suggestive of hypersensitivity, followed by cardiac arrest unresponsive to standard resuscitative measures. All the other cases promptly recovered from symptoms. Logistic regression analysis showed that allergy history and CBDCA retreatment interval (interval time between the last cycle of first-line chemotherapy and CBDCA retreatment) were independent predictive variables for the risk of hypersensitivity, whereas patient age, first-line chemotherapy, total CBDCA dose given during first-line treatment, recurrence treated with CBDCA (first versus other), and CBDCA regimen at recurrence had no predictive value. Hypersensitivity reaction rate was higher in patients with CBDCA retreatment interval longer than 23.4 months compared to those with a shorter interval (36.3% versus 8.3%, P = 0.0132). Nine patients were subsequently treated with cisplatin, and two (22.2%) still developed allergic reactions. In conclusion, hypersensitivity reactions to CBDCA retreatment can occur in approximately one fifth of the cases, and a CBDCA retreatment interval longer than 2 years appears to be the strongest predictive variable for the development of allergic reactions.

This paper presents a self-organizing neural network model for visuo-motor coordination of a redundant humanoid robot arm in reaching tasks. The proposed approach is based on a biologically-inspired model which replicates some characteristics of human control: learning occurs through an action-perception cycle and does not requires explicit knowledge of the geometry of the manipulator. The transformation learned is a mapping from spatial movement direction to joint rotation. During learning, the system creates relations between the motor data associated to endogenous movements performed by the robotic arm and the sensory consequences of such motor actions, i.e. the final position and orientation of the end effector. The learnt relations are stored in the neural map structure and are then used, after learning, for generating motor commands aimed at reaching a given point in 3D space. The work is an extension of (E. Guglielmelli, et al.) including the end-effector orientation control. Experimental trials confirmed the system capability to control the end effector position and orientation and also to manage the redundancy of the robotic manipulator in reaching the 3D target point even with additional constraints, such as one or more clamped joints without additional learning phases

This paper presents the application of a neural approach in the control of a 7-DOF robotic head. The inverse kinematics problem is addressed, for the control of the gaze fixation point of two cameras mounted on the robotic head. The proposed approach is based on a biologically-inspired model, which replicates the human brain capability of creating associations between motor and sensory data, by learning. The model is implemented here by self organizing neural maps. During learning, the system creates relations between the motor data associated to endogenous movements performed by the robotic head and the sensory consequences of such motor actions, i.e. the final position of the gaze fixation point. The learnt relations are stored in the neural map structure and are then used, after learning, for generating motor commands aimed at reaching a given fixation point. The approach proposed here allows to solve the inverse kinematics and joint redundancy problems for the ARTS robotic head, with good accuracy and robustness. Experimental trials confirmed the system capability to control the gaze direction and fixation point and also to manage the redundancy of the robotic head in reaching the target fixation point even with additional constraints, such as a clamped joint or two symmetric joint angles (e.g. eye joints).

In recent years, advances and improvements in engineering and robotics have been strengthening interactions between biological science and robotics in the goal of mimicking the complexity of biological systems. In this paper, motor control paradigms inspired by human mechanisms of sensory-motor coordination are applied to a biologically-inspired, purpose-designed robotic platform. The goal was to define and implement a multi-network architecture and to demonstrate that progressive learning of object grasping and manipulation can greatly increase performance of a robotic system in terms of adaptability, flexibility, growing competences and generalization, while preserving the robustness of traditional control. The paper presents the neural approach to sensory-motor coordination and shows preliminary results of the integration with the robotic system by means of simulation tests and experimental trials.

We present a sensory-motor coordination scheme for a robot hand-arm-head system that provides the robot with the capability to reach for and to grasp an object, while pre-shaping the fingers to the required grasp configuration. A model for sensory-motor coordination derived from studies in humans inspired the development of the scheme. A special feature of this model is the prediction of the tactile image perceived after grasping. The proposed scheme is based on a neuro-fuzzy module that, after a learning phase, starting from visual data, calculates the position and orientation of the hand for grasping, selects the best-suited hand configuration, and predicts the tactile feedback after grasping. The implementation of the scheme on a humanoid robot allowed experimental validation of its effectiveness in robotics and provided perspectives on applications of sensory predictions in robot motor control

In this article, we present a neurobiologically inspired multinetwork architecture based on knowledge of cortico-cortical connectivity and its application on an anthropomorphic head-arm-hand robotic system to provide reach-and-grasp kinematics based on multimodal sensorimotor learning. The system incorporates artificial neural network modules (matching units) trained by the locally weighted projection regression (LWPR) algorithm that enables progressive learning from simple to more complex sensorimotor tasks. We report the actual performance of the system by comparing the simulation with the experimental results obtained by the implementation on the real world artefact

In this paper we address the problem of executing fast gaze shifts toward a visual target with a robotic platform. The robotic platform is represented by an anthropomorphic head with seven degrees of freedom (DOFs) that was designed to mimic the physical dimensions (i.e. geometry and masses), the performances (i.e. angle and velocities) and the functional abilities (i.e. neck-movements and eyes vergence) of the human head. In the proposed approach the problem of coordinating and exploiting a fast gaze shift is investigated by inserting the knowledge of long-lasting neuro-physiologic studies into the control paradigm of the robot. The major advantage of this approach is that the problem of controlling the robotic artifact is reformulated as a sensory-motor integration problem. In this case, the design of the robot control itself takes great advantages of the existing neuroscientific knowledge in the field. In this approach the "golden performance" of the robotic head is represented by the accurate eye-head coordination that is observed during head-free gaze saccades in humans. To this aim, we implemented and tested on the robotic head a well-characterized, biologically inspired model of gaze control and we verified if the resulting motor output were coherent with the reported patterns of eye-head coordination in humans

This paper presents a neural model for visuo-motor coordination of a redundant robotic manipulator in reaching tasks. The model was developed for, and experimentally validated on, a neurobotic platform for manipulation. The proposed approach is based on a biologically-inspired model, which replicates the human brain capability of creating associations between motor and sensory data, by learning. The model is implemented here by self-organizing neural maps. During learning, the system creates relations between the motor data associated to endogenous movements performed by the robotic arm and the sensory consequences of such motor actions, i.e. the final position of the end effector. The learnt relations are stored in the neural map structure and are then used, after learning, for generating motor commands aimed at reaching a given point in 3D space. The approach proposed here allows to solve the inverse kinematics and joint redundancy problems for different robotic arms, with good accuracy and robustness. In order to validate this, the same implementation has been tested on a PUMA robot, too. Experimental trials confirmed the system capability to control the end effector position and also to manage the redundancy of the robotic manipulator in reaching the 3D target point even with additional constraints, such as one or more clamped joints, tools of variable lengths, or no visual feedback, without additional learning phases

The paper proposes an anticipation mechanism to improve the perception-action loop of robots interacting with real-world environments. According to recent neuroscientific findings, sensory anticipation can increase the effectiveness of perception-action loops and reduce the delays in obtaining the sensory information, especially in case of complex sensory modalities like vision, that affect pure feed-back structures. In the proposed scheme, perception crucially involves comparison processes between incoming stimuli and expected perceptions (EPs), built from previous perceptions, current motor commands, and internal models of the robot and the environment. Background knowledge plays here a helpful role, as it reduces the computational burden of perception and motor coordination tasks in partially structured environments. In the work presented here, an EP mechanism has been applied in the visuo-motor coordination of an anthropomorphic 8 d.o.f. robotic manipulator equipped with a vision system, in order to evaluate the conditions of applicability of the proposed strategy, and to validate the viability and effectiveness of the initial hypothesis.

This paper describes an experimental work conducted in order to estimate the conditions of applicability of expected perception (EP) based on a scheme for robot sensorimotor coordination. The starting hypothesis is that predictions of incoming sensory data can improve sensorymotor coordination respect to pure feedback loops. This implies that the environment presents a level of predictability, as in realistic environments. An implementation of the EP-based scheme has been realized on a platform composed by the Dexter 8-d.o.f. robotic arm and a color camera, for executing a pushing task in a real-world environment. Its performance, where defined as a combination of the error in the trajectory following and the computational effort, has been compared with that of a feedback-based system executing the same task in the same environmental conditions. The results have been put in relation with the degree of environmental predictability, which was controlled in the experimental trials. The experimental results give support and useful insights for analyzing the applicability of the EP-based scheme.

Human–robot interaction represents a critical factor in the design of personal robots as well as in the implementation of robot behavior and control. This work investigates and proposes solutions to the problem of controlling an anthropomorphic robot arm for personal assistance, by dealing with the peculiarities of its design, i.e. the mechanics of its cable-actuated, intrinsically compliant structure, and by emphasizing its potential in applications of physical and functional interaction with the environment and with human users. To satisfy the requirements of increasing the safety in the interaction and the robot functionality in tasks performed in cooperation with humans, three solutions are developed and tested for the considered personal robot. The initial idea is aimed at developing an efficient as well as computational convenient interaction control strategy, i.e. a compliance control scheme in the Cartesian space. The analysis of its limited performance suggests two further control strategies, i.e. a compliance control scheme in the joint space and an impedance–compliance control scheme. Their compared analysis points out that all the three solutions can safely operate in the human environment, but from a functional point of view only the last two schemes can effectively control the personal robot arm in its whole workspace. The paper describes the mechanics of the considered robot arm, with special regard to its anthropomorphism and cable-actuation and presents in details the three control schemes. They are critically evaluated through the experimental results achieved in tasks of physical and functional interaction with the environment and with human users. The impedance–compliance controller emerges as the more appropriate to the addressed application as well as to the peculiar cable-actuated structure.

In order to evaluate the prevalence of gestational diabetes mellitus (GDM) and the presence of risk factors for GDM, we conducted a retrospective study of a cohort of Italian women. In addition, we compared universal versus selective screening to validate the ADA's recommendations in our population. From June 1st, 1995 to December 31st, 2001, universal screening for GDM was performed in 3950 women. The glucose challenge test (GCT) was positive (GCT+) in 1389 cases (35.2%). The 1-h glucose level after GCT enabled us to diagnose GDM directly in 24 pregnant women. Oral glucose tolerance test (OGTT) was performed in 1221 GCT+ women (144 cases with GCT+ dropped out) and GDM was diagnosed in 284 (23.2%) of them. OGTT was also performed in 391 randomly chosen, women from the GCT negative (GCT-) group. In this last group 25 (6.3%) women had GDM. Thus, the total number of subjects with GDM was 333 out of 3806 with a prevalence of 8.74% in the entire cohort. Assuming that the rate of GDM observed in the random sample of GCT- women is applicable to the whole group of 2561 GCT- women, then 161 GCT- patients could also have GDM. This will further increase the estimated prevalence for the whole cohort up to 12.3% (i.e. 469 out of 3806 pregnant women). There were 236 (5.6%) women with a low risk for GDM (normal weight, age less than 25 years and without a family history of diabetes). In this group we found 34 cases and five cases with positive screening test and GDM, respectively. Thus, if we excluded low risk women from the screening test, as suggested by ADA recommendations, only five women with GDM would have been missed. However, about 95% of our population were at medium or high risk for GDM and, therefore, would have been screened. The rate of GDM was significantly higher in women with a positive history of diabetes, increasing age, previous pregnancies, pre-pregnancy overweight and short stature. After logistic regression analysis, GDM diagnosis was significantly correlated with age (P

Personal Robotics is widely recognized as a major challenge for current Robotics Research. Robots assisting humans and closely interacting with them have to meet acceptability requirements which in turn leads one to reconsider the concept of autonomy in robotics. This paper presents an abstract analysis of possible levels of semi-autonomy in Personal Robots and illustrates a case-study in which adaptable semi-autonomy is implemented and experimentally validated. Explanation modules, for human-robot communication in the planning phase, and user modeling techniques, that allow the system to adapt to its user's needs and preferences, are proposed as ways to achieve adaptive semi-autonomy

In this work, the reactivity in air of three heavy-oil fly-ashes was investigated by using two different methods: thermal analysis and a laboratory entrained-flow furnace. The combustion tests were carried out in a temperature range of 700–900 °C. The reactivity classification based on thermo-analysis data agreed well with that obtained by combustion tests in the furnace.

For the success of male reproductive processes, anther and pollen development are finely timed and choreographed (Koltunow et al. 1990; Scott et al. 1991). Gene expression is temporally and spatially regulated during anther development, producing highly differentiated cells and tissues responsible for non-reproductive and reproductive functions. Anther-specific mRNAs have been shown to encode a number of proteins (Goldberg et al. 1993; McCormick 1991). Multiple molecular events under tight gene control are also involved in the progression of microspores through the pollen developmental pathway (Bedinger and Edgerton 1990). Variations in the protein patterns of male gametophytes related to different stages of development have been widely demonstrated (Bedinger and Edgerton 1990; Delvallee and Dumas 1988; Hruba and Tupy 1998; Stinson et al. 1987; Tupy et al. 1983; Vergne and Dumas 1988). Therefore, the importance of protein degradation and turnover closely associated to the pathway of anther and pollen development can be hypothesized.

Leptin can be considered as a peripheral signal which informs the centers about the mass of energy stores. Studies done on the human adult population have demonstrated that degree of adiposity and insulin levels play a major role as determinants of leptin circulating levels. The aim of this study was to evaluate which factors may influence leptin levels at birth. We examined the role played by baby size and by the metabolic environment the fetus was exposed to during pregnancy. We considered 85 newborns from normal (n = 60), gestational (GDM, n = 17) and pregestational (IDDM = 8) diabetes mellitus mothers. At delivery, blood was taken from the umbilical cord vein. Babies from normal and GDM mothers were subdivided into AGA (appropriate for gestational age) and LGA (large for gestational age). There was no difference in leptin levels between babies from normal or GDM mothers belonging to the same weight category, but leptin levels were always higher in LGA than in AGA newborns, and highly correlated with birth weight (r = 0.34, P = 0.001). Moreover, IDDM mothers gave birth to newborns with significantly higher levels of leptin and insulin when compared with normal and GDM mothers. Diabetes of both GDM and IDDM mothers was clinically well controlled (HbA1c was 4.0 and 7.2, respectively). The correlation between leptin and insulin was significant only when newborns from IDDM mothers were included in the regression analysis (r = 0.39, P = 0.0002). Our results suggest that degree of adiposity is one of the main regulators of leptin concentration in the human newborn and that babies exposed to an altered, though clinically controlled, metabolic environment, as in IDDM mothers, have increased levels of leptin.

The development of personal robots dedicated to service tasks, such as the assistance to the disabled and the elderly at home and/or in residential institutions, is certainly one of the most attractive challenges currently being faced by the robotics community world-wide. This paper aims at providing a specific contribution to one of the most interesting technical problems related to the development of such systems, i.e. high-level control and supervision during task execution, and describes an innovative approach for a semi-autonomous personal robot for household applications, based on the concepts of 'levels of autonomy' and 'system distribution'. It also describes the implementation of such an approach for the supervisor of the MOVAID robotic system, for residential care of disabled and elderly people. In the paper, the proposed approach is presented. Its current implementation for the MOVAID prototype, based on an object-oriented behavioural scheme, is also illustrated with preliminary indications on the experimental results and possible future developments.

Rat neonatal mortality to endotoxin and age-related changes in adherent splenic cell mediator production in vitro were investigated. Neonatal rat pups, 24, 48, 96, and 216 h old or maternal adult rats were administered doses of Salmonella enteritidis endotoxin, (.024 mg to 7.5 mg/kg) and survival was monitored for 72 h. Mortality demonstrated high sensitivity (p.05) of neonates to endotoxin (particularly 24 h old neonates). Endotoxin administration .6 mg/kg intracardiac) produced a 100% lethality in 24 h neonates (p.05) versus 23% or less lethality in the 48 to 216 h old age group. Endotoxin administration (.4 mg/kg subcutaneous) also produced 100% lethality in 24 h old neonates compared with reduced mortality versus older age groups. Endotoxin in vitro stimulated (p.05) adherent splenic cell thromboxane (TX)B2, interleukin-6, and nitrite production in most groups. Splenic cell nitrite production was higher (p.05) in the 24 h old neonates, but lower in 48 h and 96 h old groups compared with maternal adults. Splenic cell TXB2 production was higher (p.05) in the 24 h and 216 h old neonates relative to maternal adults. In conclusion, 24 h old rat pups are more susceptible to endotoxic shock than older age groups and adults, and exhibit altered production of the cellular mediators nitric oxide and TXB2.

Objective To determine whether the ovary influences adrenal androgen secretion in polycystic ovary syndrome (PCOS). Design The adrenal androgen secretion was evaluated before and during ovarian suppression with a long-acting GnRH agonist. Setting Department of Obstetrics and Gynecology, Pisa, Italy. Participants Women with PCOS and high (10 subjects) and normal (12 subjects) DHEAS levels and 6 normal women. Interventions After 1 mg dexamethasone, an ACTH-(1-24) stimulation test was performed in the early follicular phase of the menstrual cycle. The test was repeated after two injections of a long-acting GnRH analogue (GnRH-a). Main Outcome Measures Basal plasma levels of gonadotropins, E 2 , T, androstenedione (A), 17 α -hydroxyprogesterone (17-OHP), DHEAS, and Cortisol (F) were evaluated before the evening administration of dexamethasone. Serum A, T, 17-OHP, DHEAS, and F were measured 9 hours after dexamethasone and in samples collected 60 and 120 minutes after ACTH IV injection. Results In the high DHEAS group the maximum increases in T, A, 17-OHP, and DHEAS in response to ACTH were significantly higher than in normal DHEAS PCOS women and in normal women. The GnRH-a modified the A and T responses to ACTH in the high DHEAS group. Conclusions Ovarian steroids, or other extra-ovarian factors, seem to be responsible for the increased A and T responses to the corticotropin stimulation demonstrated in some PCOS women.

It is well known that targets moving along track within a Synthetic Aperture Radar (SAR) field of view are imaged as defocused objects. The SAR stripmap mode is tuned to stationary ground targets and the mismatch between the SAR processing parameters and the target motion parameters causes the energy to spill over to adjacent image pixels, thus not only hindering target feature extraction, but also reducing the probability of detection. The problem can be remedied by generating the image using a filter matched to the actual target motion parameters, effectively focusing the SAR image on the target. For a fixed rate of motion the target velocity can be estimated from the slope of the Doppler frequency characteristic. The processing is carried out on the range compressed data but before azimuth compression. The problem is similar to the classical problem of estimating the instantaneous frequency of a linear FM signal (chirp). This paper investigates the application of three different time-frequency analysis techniques to estimate the instantaneous Doppler frequency of range compressed SAR data. In particular, we compare the Wigner-Ville distribution, the Gabor expansion and the Short-Time Fourier transform with respect to their performance in noisy SAR data. Criteria are suggested to quantify the performance of each method in the joint time- frequency domain. It is shown that these methods exhibit sharp signal-to-noise threshold effects, i.e., a certain SNR below which the accuracy of the velocity estimation deteriorates rapidly. It is also shown that the methods differ with respect to their representation of the SAR data.

Mathematical formalism and computational considerations have led to the development of nonstationary filtering concepts that use coherent frames to exploit waveform frequency content that is localized in time. This paper deals with nonstationary filtering concepts that utilize phase space information provided by the Weyl-Heisenberg and wavelet coherent frames. In both cases, the frame formulations possess optimum simultaneous localization in phase space that follows from the use of Gaussian based frame functions. A filtering procedure is presented that first formulates a noise-free waveform signature template in phase space, and then uses this template for nonstationary filtering. The nonstationary filtering operation can be applied either before or after classical matched filtering to obtain improved peak signal-to-root mean square (rms) noise ratio (SNR) performance for enhanced detection or waveform feature extraction. The advantage arises from exploiting the time varying spectrum of the waveform. The manner in which the SNR improvement comes about is examined so that it can be properly interpreted in the context of candidate applications. The procedure is described and the performance is demonstrated using both the Weyl- Heisenberg and wavelet coherent frames applied to examples of linear FM and Barker coded waveforms. The nonstationary filter performance used with the matched filter is compared to classical stationary matched filter performance for the case of additive white Gaussian noise.

Group B streptococci (GBS) are a leading cause of sepsis and meningitis in neonates. Since cytokines are thought to play an important role in septic shock, we have studied serum levels of tumor necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6) in BALB/c mice infected with type III GBS. TNF alpha and IL-6 were detected by the L929 cytotoxicity and the B9 proliferation assays, respectively, in serial serum samples obtained after infection. After i.p. challenge with an LD50, serum TNF alpha rose above baseline values as early as 3 hr, peaked at 7 hr, and returned to baseline values at 20 hr. IL-6 serum levels rose concomitantly with TNF alpha, peaking 8 hr after challenge. No serum TNF alpha activity was detected in the course of sublethal infections. However, a transient rise in TNF alpha levels was observed after i.v. inoculation of high numbers (greater than or equal to 1 x 10(8) of heat-killed GBS. When groups of mice were injected i.v. with a single dose of anti-TNF alpha rabbit serum 2 hr before challenge with an LD90 or LD30, no effect was noted in terms of survival, although the serum TNF alpha peak was completely abrogated. Serum TNF alpha does not seem to play an obligatory role in GBS-induced lethality of adult mice. However, further studies are needed to assess better the role of this cytokine in the pathogenesis of GBS sepsis.