bluuebunny/crossref_metadata_2025_split huggingface dataset:
Century-scale variability in late-summer rainfall events recorded over seven centuries in subannually laminated lacustrine sediments, White Pass, British Columbia
Authors: Cockburn Jaclyn M.H. , Lamoureux Scott F. 
Published: January 2007

AbstractFormation of annually laminated sediments in Summit Lake, White Pass, British Columbia is controlled by runoff generated by snowpack and glacier melt and major rainfall events. The 700-yr varve record is divided into two subannual series (early and late) based on sedimentological criteria and sedimentary structures within each varve. A comparison of recent subannual laminae with nearby meteorological records supports the interpretation they are formed by river discharge events generated by major snow and glacier melt events and large late-summer rainfall events. A significant correlation exists between the late subannual thickness series and the size of the largest rainfall events in late summer. The long record indicates there was an abrupt increase in the thickness and frequency of major rainfall-induced sedimentary events at the end of the seventeenth century. In addition, the frequency of laminae generated by early runoff events also increased. However, early subannual varve thickness component remains statistically the same as the thickness prior to the end of the seventeenth century. This suggests the change in varve thickness at this time is due to increases in major late-summer rainfall frequency rather than increased sediment availability caused by regional Little Ice Age glacier advances.
High-speed navigation of unmanned ground vehicles on uneven terrain using potential fields
Authors: Shimoda Shingo , Kuroda Yoji , Iagnemma Karl 
Published: January 2007

SUMMARYMany applications require unmanned ground vehicles (UGVs) to travel at high speeds on sloped, natural terrain. In this paper, a potential field-based method is proposed for UGV navigation in such scenarios. In the proposed approach, a potential field is generated in the two-dimensional “trajectory space” of the UGV path curvature and longitudinal velocity. In contrast to traditional potential field methods, dynamic constraints and the effect of changing terrain conditions can be easily expressed in the proposed framework. A maneuver is chosen within a set of performance bounds, based on the local potential field gradient. It is shown that the proposed method is subject to local maxima problems, rather than local minima. A simple randomization technique is proposed to address this problem. Simulation and experimental results show that the proposed method can successfully navigate a small UGV between predefined waypoints at speeds up to 7.0 m/s, while avoiding static hazards. Further, vehicle curvature and velocity are controlled during vehicle motion to avoid rollover and excessive side slip. The method is computationally efficient, and thus suitable for onboard real-time implementation.
Development of an image-guided robotic system for surgical positioning and drilling
Authors: Tseng Ching-Shiow , Huang Chiao-Chi , Chen Chen-San 
Published: January 2007

AbstractThis study develops a novel image-guided robotic system that can be used to position biopsy needles or drill fixation holes. After the patient has received a CT-scan, the registration of the image, localizer (patient), and robot frames will be done by finding the optimum transformation matrix among the image and localizer coordinates of the fiducial markers and the DRFs mounted on the robot. Then, surgical paths planned on the computer displayed images can be transformed to the robot frame, and the robot is thus capable to move surgical tools to the preplanned location. The positioning error is about 2 mm and the orientation error is about 0.23°.
Velocity space approach to motion planning of nonholonomic systems
Authors: Duleba Ignacy , Khefifi Wissem 
Published: January 2007

SUMMARYIn this paper, a velocity space method of motion planning for nonholonomic systems is presented. This method, based on Lie algebraic principles and locally around consecutive current states, plans a motion towards a goal. It is effective as most of the computations can be carried out analytically. This method is illustrated on the unicycle robot and the inverted pendulum.
Real-time motion planning for robot manipulators in unknown environments using infrared sensors
Authors: Wang Shuguo , Bao Jin , Fu Yili 
Published: January 2007

SUMMARYThis paper deals with sensor-based motion planning method for a robot arm manipulator operating among unknown obstacles of arbitrary shape. It can be applied to online collision avoidance with no prior knowledge of the obstacles. Infrared sensors are used to build a description of the robot's surroundings. This approach is based on the configuration space but the construction of the C-obstacle surface is avoided. The point automation is confined on some planes with square grids in the C-space. A path-searching algorithm based on square grids is used to guide the automation maneuvering around the C-obstacles on the selected planes. To avoid the construction of the C-obstacle surface, the robot geometry model is expanded, and the static collision detection method is used. Hence, the computation time is reduced and the algorithm can work in real time. The effectiveness of the proposed method is verified by a series of experiments.
A novel PID control parameters tuning approach for robot manipulators mounted on oscillatory bases
Authors: Lin J. , Huang Z.-Z. 
Published: January 2007

SUMMARYThis research focuses on the issue of dynamic modeling and controlling a robotic manipulator attached to a compliant base. Such a system is known under the name macro–micro system, characterized by the number of control actuators being less than the number of state variables. The equations of motion for a two-link planar elbow arm mounted on an oscillatory base has been presented in this investigation. In order to study the sensitivity of tuning the PID parameters to achieve the desired performance, the Grey relational analysis has first been proposed. Therefore, the aim of this work is to apply Grey theory to optimize parameters for partial states feedback of a PID controller for such a structure. The experimental results of the proposed methodology also show that it is technically and economically feasible to develop a low-cost, reliable, automatic, less time-consuming controller for robotics mounted on oscillatory bases.
An integrated agent-based software architecture for mobile and manipulator systems
Authors: Nebot Patricio , Cervera Enric 
Published: January 2007

SUMMARYMobile manipulation involves the most important key issue in robotics: integration. While hardware integration seems to be nearly solved due to the increasing dominance of PC-compatible systems, software integration is still a challenge, since a lot of issues arise with the variety of operating systems, device drivers, application libraries, and programming languages which need to be merged in any real-world robotic system. This paper presents a software architecture, which seamlessly integrates robot arms, mobile bases, vision systems and sensing devices, in a distributed, homogeneous agent framework. Based on the Java platform, the agent-based architecture allows great flexibility in the integration of components, and provides a simple yet extensible and powerful software layer to develop further mobile manipulating environments. Detailed software issues, as well as preliminary results are shown, which pave the way towards the development of network-ready applications involving mobile and manipulating artifacts.
Mapping the integration of social and ethical issues in health technology assessment
Authors: Lehoux Pascale , Williams-Jones Bryn 
Published: January 2007

Background:Since its inception, the field of health technology assessment (HTA) has stressed the need for consideration of ethical and social issues. However, few concepts or analytic tools have been developed, and because of the complexity of the endeavor and a lack of integration of work already produced, such concepts remain difficult to apply in HTA.Objectives:Through a descriptive “map” of concepts, tools, and processes, we summarize the most tangible efforts on the part of HTA producers to address social and ethical issues.Methods:A literature review and content analysis of HTA reports in the Centre for Reviews and Dissemination database enables a synthesis of the reflections on, initiatives around, and gaps in knowledge related to the integration of social and ethical issues in HTA.Results:We examine: (i) the aim of integrating ethical and social issues in HTA, (ii) the theoretical approaches used, (iii) the methods and processes applied, and (iv) the implications for HTA producers. We highlight two levels at which social and ethical issues can be considered: throughout the production process of HTA reports and as part of the organizational structure of HTA agencies.Conclusions:Given the profound societal changes that occur in relation to healthcare technology development, HTA producers have a responsibility to inform and enlighten technology-related public and policy debates. Fulfilling this role, though, requires that socioethical dimensions of technologyandHTA are made explicit.
Economic evaluations of leukemia: A review of the literature
Authors: Kasteng Frida , Sobocki Patrik , Svedman Christer , Lundkvist Jonas 
Published: January 2007

Objectives:Leukemia, together with lymphoma and multiple myeloma, are hematological malignancies, malignancies of the blood-forming organs. There are four major types of leukemia: acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), and chronic lymphocytic leukemia (CLL). There is a growing amount of literature of the health economic aspects of leukemia. However, no comprehensive review is yet performed on the health economic evidence for the disease. Hence, our aim was to review and analyze the existing literature on economic evaluations of the different types of leukemia.Methods:A systematic literature search used electronic databases to identify published cost analyses and economic evaluations of leukemia treatments. After reviewing all identified studies, sixty studies were considered relevant for the purpose of the review.Results:The identified studies were published after 1990, with a few exceptions. Many of the identified economic evaluations in leukemia, particularly for ALL and AML, may be defined as cost-minimization analyses, where only the costs of different treatment strategies are compared. In CML, a new treatment, imatinib, was introduced in 2001 and several cost-effectiveness analyses have since then been conducted comparing imatinib with previous first line treatments.Conclusions:This review indicates that there is a shortage of cost-effectiveness information in leukemia. The introduction of new therapies will stress the need for new economic evaluations in this group of diseases. More information about the total costs, that is, including indirect costs, and quality of life effects would be valuable in future evaluations in leukemia.
Effectiveness and safety of endoscopic thoracic sympathectomy for excessive sweating and facial blushing: A systematic review
Authors: Malmivaara Antti , Kuukasjärvi Pekka , Autti-Ramo Ilona , Kovanen Niina , Mäkelä Marjukka 
Published: January 2007

Objectives:Despite controversies, endoscopic thoracic sympathectomy (ETS) has been used as a treatment for excessive sweating of hands and face and for facial blushing. This study aims to evaluate the effectiveness of ETS for the current indications in a systematic review.Methods:Controlled clinical trials and cohort studies with more than 100 patients were included. Abstracts were searched from MEDLINE and CCTR from 1966 to June 2004. Two reviewers extracted the data and assessed study quality. Data on effectiveness and safety were synthesized qualitatively.Results:We did not find any controlled clinical trials. Fifteen prospective studies were included. The internal and external quality of these studies were poor overall. Follow-up was commonly less than 2 years, during which time excessive sweating and facial blushing seemed to decrease among most patients. Immediate complications related to thoracoscopy occurred in up to 10 percent of patients. Compensatory sweating below breast level was reported in up to 90 percent of the patients. Other common side effects included dryness of face and hands, gustatory sweating, and neuralgic pain. Several other less common side effects were reported.Conclusions:The evidence of the effectiveness of ETS is weak due to a lack of randomized trials. The intervention leads to severe immediate complications in some of the patients, and to persistent side-effects for many of the patients.
Telemedicine in pediatric and perinatal cardiology: Economic evaluation of a service in English hospitals
Authors: Dowie Robin , Mistry Hema , Young Tracey A. , Weatherburn Gwyn C. , Gardiner Helena M. , Rigby Michael , Rowlinson Giselle V. , Franklin Rodney C. G. 
Published: January 2007

Objectives:Pediatric cardiology has an expanding role in fetal and pediatric screening. The aims of this study were to observe how district hospitals use a pediatric telecardiology service, and to compare the costs and outcomes of patients referred to specialists by means of this service or conventionally.Methods:A telemedicine service was set up between a pediatric cardiac center in London and four district hospitals for referrals of second trimester women, newborn babies, and older children. Clinicians in each hospital decided on the role for their service. Clinical events were audited prospectively and costed, and patient surveys were conducted.Results:The hospitals differed in their selection of patient groups for the service. In all, 117 telemedicine patients were compared with 387 patients seen in London or in outreach clinics. Patients selected for telemedicine were generally healthier. For all patients, the mean cost for the initial consultation was £411 for tele-referrals and £277 for conventional referrals, a nonsignificant difference. Teleconsultations for women and children were significantly more expensive because of technology costs, whereas for babies, ambulance transfers were much more costly. After 6-months follow-up, the difference between referral methods for all patients was nonsignificant (telemedicine, £3,350; conventional referrals, £2,172), and nonsignificant within the patient groups.Conclusions:Telemedicine was perceived by cardiologists, district clinicians, and families as reliable and efficient. The equivocal 6-month cost results indicate that investment in the technology is warranted to enhance pediatric and perinatal cardiology services.
Cost-effectiveness analysis of prenatal diagnosis intervention for Down's syndrome in China
Authors: Chen Yingyao , Qian Xu , Li Jun , Zhang Jie , Chu Annie , Schweitzer Stuart O. 
Published: January 2007

Objectives: The cost-effectiveness of prenatal diagnosis intervention for Down's syndrome (DS) in China was assessed and evidence-based information for policy makers and providers is presented.Methods: Based on field surveys in four selected cities in China and a literature review, the economic evaluation of prenatal diagnosis for DS from a societal perspective is conducted by cost-effectiveness analysis.Results: In current clinical practice, for a cohort of 10,000 pregnant women, the strategy that delivers karyotyping by chorionic villus sampling (CVS) or amniocentesis (AC) only to those pregnant women 35 years of age and older (maternal age screening strategy) can detect .67 DS births. The strategy that offers the diagnostic test after maternal serum screening with α-fetoprotein and human chorionic gonadotrophin (maternal serum screening strategy) can detect 1.41 DS births. The cost per prevented DS birth by the maternal age screening strategy and maternal serum screening strategy is US$13,091 and US$56,048, respectively. Sensitivity analysis shows that the maternal serum screening strategy can be cost-effective if uptake rate of CVS or AC for patients with positive serum tests increase while the cost of serum screening decreases.Conclusions: Although, in general, serum screening has been found to be more cost-effective than maternal age screening, this appears not to be the case in China. The reasons appear to be low uptake rate of the maternal serum strategy, low uptake rate of CVS or AC, and the high price of serum screening. Our findings are that health system factors concerning technology utilization are important determinants of the technology's efficiency.
Emerging Technologies: Systems Biology
Authors: Srivastava Ranjan , Varner Jeffrey 
Published: January 2007

AbstractThe field of systems biology is based on the paradigm that the whole is greater than the sum of the parts. Through a combination of high‐throughput experiments analyzing “‐omic” scale phenomenon and the development of new computational techniques and algorithms, it is now feasible to study biological systems in a way that was previously not possible. During the 232nd National Meeting of the American Chemical Society, a session devoted to the emerging technology of Systems Biology was held. A number of talks on a wide variety of subjects covering cell signaling, network regulation and analysis, novel experimental procedures, synthetic biology, and metabolic flux analysis were presented. All of these approaches shared the common theme of using a systems biology approach to aid in the understanding of fundamental biology, with an eye toward applications for the benefit of society.
ESCA and UPS Spectra of Nitronaphthylamines. Shake-up structures, relaxation effects and through-space interaction between the two substituents
Authors: Giuseppe Distefano  , Derek Jones  , Alberto Modelli  , Salvatore Pignataro  
Published: January 2007

The X-ray and UV photoelectron spectra of several nitronaphthylamine isomers are reported. In some cases, the nitro N1ssignal is accompanied by an intense satellite band 1.5-2.0 eV from the main photoline having 60-150% of its intensity; also in the corresponding O1senergy region a satellite band is present having a larger energy separation from the main peak (2.0-2.35eV) and smaller relative intensity (Ish= 10-30%). The difference between the ionization energy values of the nitro and amino N1ssignal (ΔN1s) is found to follow the same trend found for the intensity of the satellite and log ϵ, the optical absorption coefficient of the HOMO-LUMO charge-transfer (CT) transition.These satellites are ascribed to a shake-up process involving a CT transition from the naphthylamine part of the molecule towards a π* MO localized on the nitro group on the basis of a simple model we have previously proposed for nitroanilines and other aromatic derivatives.The trend of ΔN1sis thought to derive mainly from a greater "interatomic" valence band relaxation accompanying nitro N1sionization than amino N1sionization, rather than from variation of the ground state charges at the two nitrogen atoms.The UPS spectra indicate that there is no sizeable variation of the ground state mesomeric interaction between the two substituents on changing the position of the nitro group, and suggest mutual interaction of the two substituents when they are adjacent.
Electron Spectroscopic Study of Nitric Oxide Adsorbed on Copper
Authors: M H Matloob  , M W Roberts  
Published: January 2007

The interaction of NO with copper has been investigated by electron spectroscopy. Nitric oxide is shown to be molecularly adsorbed in a linearly bonded configuration at 85 K; this adlayer is unstable above 120 K, resulting in an exclusively oxygen adlayer at 295 K, the nitrogen being desorbed. At 85 K N(1s) peaks observed at 401 and 406 eV are associated with two different surface species. We suggest that the former dissociates while the latter desorbs at a binding energy of 406 eV on thermal activation of the adlayer.
Interaction of nitric oxide with Cu at 295 K results in dissociative chemisorption with both oxygen and nitrogen retained at the surface. The surface concentration suggests that each nitrogen and oxygen adatom is bridge-bonded to two surface copper atoms. Estimates of absolute surface coverages are made by comparing the intensities of the N(1s) and O(1s) peaks with the Cu(2p) substrate intensity, while valence level spectroscopy (He I and II radiation) supplements core-level spectroscopy for discriminating between molecular and dissociated surface species.
Assessment of degradation and generation of humus in a coffee soil affected by weed cover by means of a stable carbon isotopic ratio
Authors: Watanabe A. , Takada H. , Sarno  , Afandi  , Adachi T. , Oki Y. , Senge M. 
Published: January 2007

SummaryWe evaluated the effect of soil conservation by weeds on the degradation and generation of humic acids, fulvic acids, and water‐soluble non‐humic substances (WS‐NHS) in a red‐acid soil (Vertic Dystrudept) (Indonesia) from the changes in humus composition and stable carbon isotopic ratio (δ13C). Three plots, a weeded plot (T‐1; the common practice), a plot covered with Paspalum conjugatum Berg., a C4 plant (T‐2), and a plot in which native weeds were allowed to grow (T‐3), were prepared. An incubation experiment determined the δ13C values of the humus fractions generated from Paspalum in soil. Based on the increase in δ13C value, the proportion of total C that originated from Paspalum C after 4 years under coffee was 16 ± 4% in the T‐2 topsoil (0–10 cm). Humic and fulvic acids in the T‐1 topsoil decreased to 46 and 84%, respectively, whilst both increased or remained constant in the T‐2 and T‐3 soils. The WS‐NHS content varied little and was independent of land management. The preferential loss of the humic acids with a smaller degree of humification as assessed by their darkness in colour was shown in T‐1. The decrease in the degree of humification suggested the accumulation of the weed‐derived humic acids in T‐2 and T‐3. In the T‐2 topsoil, 36 ± 2%, 13 ± 3% and 15 ± 2% of C in the humic acids, fulvic acids and WS‐NHS, respectively, were estimated to be Paspalum‐derived after 4 years. The estimated initial C loss during the same period was 17 ± 3%, 14 ± 2% and 7 ± 2%, respectively, for those fractions, which suggests the fastest turnover rate for the humic acids and significant retardation of their degradation in soil colonized by weeds.
Effects of transverse movement of water in xylem on patterns of water transport within current‐year shoots of kudzu vine, Pueraria lobata
Authors: TANEDA H. , TATENO M. 
Published: January 2007

Summary

This study investigated the effects on water transport patterns of the transverse water movement in xylem, on a whole‐shoot scale, using current‐year shoots of kudzu vine (Pueraria lobata (Willd.) Ohwi).
The connections between xylem vessels were detected by dye injection and were found to be distributed throughout the internode. This means that short internodes limit the connections between vessels. The hydraulic conductance of the internode‐to‐petiole path decreased with successive cutting of the internodes.
To estimate hydraulic patterns at the whole‐shoot scale, the hydraulic conductance of the shoot base‐to‐petiole path (KBP) were measured. These were compared with two mathematical models representing extreme examples of connections between vessels – the interconnected model and the independent model. The former model assumes a high capacity for the transverse movement of water in xylem tissues. The KBP values measured were explained more accurately by the interconnected model than by the independent model.
These results suggest that kudzu vine has a large capacity for the transverse movement of water in xylem, which contributes to the effective transport of water from internodes to leaves that offsets sectored transport at the whole‐shoot scale.