35 research outputs found
Prognostic factors for esophageal squamous cell Carcinoma-A Population-Based study in Golestan province, Iran, a high incidence area
Golestan Province in northern Iran is an area with a high incidence of esophageal squamous cell carcinoma (ESCC). We aimed to investigate prognostic factors for ESCC and survival of cases in Golestan, on which little data were available. We followed-up 426 ESCC cases participating in a population-based case-control study. Data were analyzed using the Kaplan-Meier method and the Cox proportional hazard models. Median survival was 7 months. Age at diagnosis was inversely associated with survival, but the association was disappeared with adjustment for treatment. Residing in urban areas (hazard ratio, HR = 0.70; 95 CI 0.54-0.90) and being of non-Turkmen ethnic groups (HR = 0.76; 95 CI 0.61-0.96) were associated with better prognosis. In contrast to other types of tobacco use, nass (a smokeless tobacco product) chewing was associated with a slightly poorer prognosis even in models adjusted for other factors including stage of disease and treatment (HR = 1.38; 95 CI 0.99-1.92). Opium use was associated with poorer prognosis in crude analyses but not in adjusted models. Almost all of potentially curative treatments were associated with longer survival. Prognosis of ESCC in Golestan is very poor. Easier access to treatment facilities may improve the prognosis of ESCC in Golestan. The observed association between nass chewing and poorer prognosis needs further investigations; this association may suggest a possible role for ingestion of nass constituents in prognosis of ESCC. © 2011 Aghcheli et al
Emulating On-Orbit Interactions Using Forward Dynamics Based Cartesian Motion
The paper presents a novel Hardware-In-the-Loop (HIL) emulation framework of
on-orbit interactions using on-ground robotic manipulators. It combines Virtual
Forward Dynamic Model (VFDM) for Cartesian motion control of robotic
manipulators with an Orbital Dynamics Simulator (ODS) based on the Clohessy
Wiltshire (CW) Model. VFDM-based Inverse Kinematics (IK) solver is known to
have better motion tracking, path accuracy, and solver convergency than
traditional IK solvers. Therefore it provides a stable Cartesian motion for
manipulator-based HIL on-orbit emulations. The framework is tested on a
ROS-based robotics testbed to emulate two scenarios: free-floating satellite
motion and free-floating interaction (collision). Mock-ups of two satellites
are mounted at the robots' end-effectors. Forces acting on the mock-ups are
measured through an in-built F/T sensor on each robotic arm. During the tests,
the relative motion of the mock-ups is expressed with respect to a moving
observer rotating at a fixed angular velocity in a circular orbit rather than
their motion in the inertial frame. The ODS incorporates the force and torque
values on the fly and delivers the corresponding satellite motions to the
virtual forward dynamics model as online trajectories. Results are comparable
to other free-floating HIL emulators. Fidelity between the simulated motion and
robot-mounted mock-up motion is confirmed.Comment: Submitted to ICRA2023, for associated video, see:
https://www.youtube.com/watch?v=N2KYCKJ4KM
An assistive robotic hand based on human computer interface (HCI) and shape memory alloy (SMA) actuator
Rehabilitation and assistive robotics is an emerging field of research where researchers are trying to develop
tailored made robotic devices to address the challenge of disability. This paper presents a study on feedback
controlled wearable robotic hand for grasping. The proposed design is compact and sufficiently light to be
used as an assistive hand. It is tendon driven and jointless
structure that has the potential to be used as an
assistive device for stroke patients. The concept has been implemented for index and thumb fingers as a first
prototype to enable grasping. Shape memory alloy (SMA) actuator and bias force mechanism are used for the
purpose of hand’s flexion and extension. This paper describes the mechatronic design of the wearable hand,
simulation, modeling, and development of the actuation unit and sensory system. Experiments of open loop
controller were conducted to understand the hand characterization and grip force provided by index finger. A
feedback controller (proportional controller) was implemented for this prototype with gripping force as the
feedback parameter. It was observed that approximately 2.25 A current caused 4 cm displacement for SMA
actuator. The maximum temperature of the SMA actuator was achieved to be 100 °C. The attainable gripping
force was around 2 N for a load free finger. The conducted experiments showed promising results that
encourages further development on this
Microscopic structure of the intestine of beluga (Huso huso) from hatching until ranching to sea
Microscopic structure of intestine of beluga was studied from hatching until releasing to sea. Larvae were fixed in bouin’s solution, dehydrated and embedded in paraffin wax. Sections of 5-7 μm thick were produced and stained according to standard histological techniques: Hematoxylin-Eosin (HαE) and Periodic Acid Schiff (PAS). One day old larvae possessed a primordial intestine, which is lined by a simple columnar ciliated epithelium. At 3 days after hatching, an oblique furrow of the digestive tube wall started to develop on the dorsal- posterior region of the yolk sac and divided the alimentary canal into two differentiated regions: the future stomach and intermediate intestine. At this time spiral valve started to differentiate. Granules of embryonic pigment accumulated in the spiral valve lumen forming the melanin plug. At 7 days after hatching intermediate gut and spiral gut were lined by a columnar ciliated epithelium. The terminal section of the digestive tract was differentiated into a short rectal duct lined with a cuboidal epithelium. The urinary bladder connected with rectum at this time. At 13 days after hatching the number of vacuoles filled with lipid increase in intermediate gut and spiral gut. Between 17-19 days post hatching beluga larvae have a period of mixed nutrition. At 25 days after hatching cells of intermediate gut showed long microvilli. At 36 days after hatching the number of goblet cells increased in spiral gut. At 43 days after hatching several intestine glands were visible in connective tissue of intermediate gut which was lined by a simple columnar ciliated epithelium. Between 57-75 days after hatching the number and size of mucosal folds increased in intestine. This information may be useful to improve rearing efficiency of beluga and the other sturgeons
Survey on health status in aquaculture sturgeons centers (Mazandaran, Guilan And Golestan Provinces)
Study of survey health management and diseases in hatcheries and fish farms can help us to knowledge and application control methods such as: prevention, treatment and increase high levels of production in hatchery and farms, finally. This survey carried out from 2005 to 2008 for 4 years in sturgeon hatcheries and farms of Golestan province. Sturgeon fishes include Huso Huso, Ship sturgeon, Acipenser persicus collected and for virology, bacteriology, fungius and hematology examined. Also, physicochemical parameters measured and recorded in different stages of culture. Results of this study showed that all of samples in virology was negative and did not observe any doubetful causes. In bacteriology CFU was variation from 3/9 ×105 to 6/9×10. The most parasites that detected in this survey was Cocolanus espherolanus, Sceria binopsulus semiarmatus and Amphilina fuliacea that separates from Acipenser Percicus, especially. The results about hematology parameters some important hematological indices of ship sturgeon include: The total RBC for female and mail specimens measured as 5.3±1.5 ×10^5, 4.8±0.5×10^5 per mm^3 respectively. The amount of haematocrit and hemoglobin for female and mail determined: 34.3±2.8, 35±1.4 percent and 10.3±0.9, 8.9±0.8 gr/dl .The MCV: 216.3± 96.2, 736.5± 102.5, MCH: 720.2±309.5, 186±0.7 and MCHC: 30±0.8, 25.5±3.4 percent respectively.The total WBC were (female, male): 21320±1054, 20580±777 per mm^3 and neutrophil: 16.4±2.5, 17±1.4 percent and lymphocyte: 74.4±2.4, 73.5± 0.7 percent and eosinophil: 6±1.4, 6.4±0.5 percent, monocyte: 2.8±0.8, 3.5±0.7 percent. There was not any significant differences (p>0.05) between mentioned parameters in male and female (students t-test). Also evaluation of hematological parameters in bluga ( Huso huso) include: total RBC were (male , female) 5±0.3 ×105 , 4.9±0.6 ×105 per mm^3 ,respectively and hematocrit: 33.2±6.7 , 35.4±3.4 percent and hemoglobin: 11.2±1.5 , 12.2±1gr/dl and MCV: 669.9±172.2, 723.9±982.4 and MCH: 226.2±42.5, 249.5±35.4 and MCHC: 34.1±2.4, 34.6±3.6 percent respectively. The totals WBC were (male, female): 24800±707.1, 23042±1375.4 per mm^3 and neutrophil: 18.5±0.7, 21.4±1.1 percent and lymphocyte: 73.5±1.4, 68.4±1.1 percent and eosinophil: 5±2.8, 7±1.2 percent and monocyte: 3.5±3.5, 3.2±0.8 percent. According to statistically study the count of lymphocyte had significant difference between male and female fish and this count in male was higher than female. (p≥0.05)
Sand fly synthetic sex-aggregation pheromone co-located with insecticide reduces the incidence of infection in the canine reservoir of visceral leishmaniasis: a stratified cluster randomised trial
The predominant sand fly vector of the intracellular parasite Leishmania infantum, that causes human and canine visceral leishmaniasis in the Americas, is Lutzomyia longipalpis. Dogs are the proven reservoir. Vector control tools to reduce transmission suited to this predominantly exophilic vector are lacking. Insecticide-impregnated dog collars protect dogs against infectious bites from sand fly vectors, and result in reductions of new infections in both dogs and humans. However, collars are costly for endemic communities, and alternative approaches are needed. Recently the bulk synthesised sex-aggregation pheromone of male Lu. longipalpis was shown to attract large numbers of conspecific females to lethal pyrethroid insecticides, indicating the potential for use in a vector control application. This study, conducted in Brazil, evaluated the efficacy of this novel lure-and-kill approach to reduce seroconversion and infection incidence with L. infantum in the canine reservoir, in addition to measuring its impact on household abundance of Lu. longipalpis. Deployed in 14 stratified clusters, the outcomes were compared to those attributed to insecticide impregnated collars fitted to dogs in another 14 clusters; each intervention was compared to 14 clusters that received placebo treatments. The beneficial effects of the lure-and-kill method were most noticeable on confirmed infection incidence and clinical parasite loads, and in reducing sand fly abundance. The overall effect of the two interventions were not statistically dissimilar, though the confidence intervals were broad. We conclude that the novel low-cost lure-and-kill approach should be added to the vector control toolbox against visceral leishmaniasis in the Americas
Development and performance evaluation of a linear actuator based wearable assistive device
For an assistive device to be usable in carrying out
activities of daily living, it is highly important that the device be
compact, light in weight and portable. It is even more important
that the device be comfortable and safe to use. As different
people have different hand sizes, the assistive hands must be
designed considering the variety of hand sizes that can be
accommodated without any compromise in safety or comfort.
This can be best achieved by making use of a joint-less structure
that takes the shape of the hand that wears it. This paper
proposes the design of an assistive device that is lightweight,
compact, safe and comfortable. This device assists the hand in
gripping objects used in daily life activities. The performance
evaluation of this device is carried out by measuring the gripforce
exerted by the finger-tip on the object. The maximum
range of grip-force exerted by this assistive hand is between 2.5
to 4.5 N. The minimum grip-force that can be applied is 0.9 N.
The experiments conducted show the viability of the assistive
device
Modified prone position to dissect the popliteal fossa
Introduction: Traditionally, the prone position is used for dissecting the popliteal fossa, which requires endotracheal intubation. Access to the airway in this position is limited, hence the complications. It is not surprising that the prone position is not favoured by the anaesthetists, especially in patients with a high body mass index. We describe a safe and novel alternative to the prone position. Methods: The modified prone position (MPP) is described as an alternative position that facilitates access to the airway. Results: Between October 2007 and May 2010, 12 patients underwent popliteal fossa dissection using the MPP. All patients had general anaesthesia using a laryngeal mask airway with the exception of one, who had an epidural anaesthesia. There were no airway or haemodynamic complications. The surgical access to the popliteal fossa was as good as with the traditional prone position. Conclusions: The MPP was satisfactory for both the surgeon and the anaesthetists. The authors now use this position routinely for dissecting the popliteal fossa