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We're concerned with future accelerators of high intensity protons for isotope production. To this end, we initiate a proposal to design an innovative superconducting H+ 3 cyclotron TR150, aiming at proton energy of 70–150 MeV and proton current of ∼ 1.0 mA. Cyclotrons in this energy range are not developed world-wide; moreover numerous highly interesting and increasingly demanded radio­nuclides are in this energy range. Our machine shall be designed to accelerate H+ 3 ion, the simplest and stable triatomic molecular ion, by injection from an external ion source and extraction by stripping. This has potential to extract proton beam of variable energies with very high extraction efficiency, and thus enables to simultaneously provide multiple proton beams for multiple external production targets. A baseline design of our machine and the beam dynamics studies are presented in this paper.

Passive magnetic channel is a kind of beam focusing elements in a cyclotron. It consists of several soft iron bars that are magnetized by the main field in a cyclotron. In this paper, we proposed a topology optimization method to design the pole shape in passive magnetic channel, this method does not require any fixed geometry pattern or initial design. The nonlinear static magnetic finite-element analysis model is used to calculate the objective magnetic field function. Persuade iron material with variable density is used to describe the iron distribution during the iteration. Method of Moving Asymptotes (MMA) is used to optimize the control variable of iron density distribution on magnetic channel cross-section. In three numerical examples, magnetic channels for a 250 MeV superconducting cyclotron is provided, where the design goal is to provide the given magnetic field gradient and bending angle. The relationship between the design goal and the pole shape pattern is discussed. It reveals that magnetic channel pattern with only 2 iron bars is possible for some design goals.

Two AC magnets were installed to scan the 500 MeV proton beam in a circular pattern on the TRIUMF ISAC target. Rotating the proton beam produces a more uniform average power deposition, which increases the maximum amount of total beam power that targets can tolerate. The magnet system consists of a pair of two ferrite AC magnets that rotate the proton beam at a frequency of up to 400 Hz. A new tune was developed to produce a controllable spot size, while having an approximate parallel beam on target and a 90° phase advance between the raster magnets and the target. A set of diagnostics was developed to monitor the rotating beam. Online tests have shown that we can increase the radioactive ion beams (RIB) yields from a target while maintaining same maximum temperature.

Study Design: This is a prospective observational study of 60 consecutive cases with facial scars and contour deformity who underwent structural fat grafting. Objectives: The aim of the present article is to highlight how fat grafting helps to improve aesthetic and functional outcome in facial scars and contour deformities. It also highlights the factors that need to be considered while planning autologous fat grafting to get better aesthetic results. Methods: This is a prospective observational study of 60 consecutive cases with facial scars and contour deformity. The study was conducted from May 2014 to April 2019 in a tertiary care hospital. All the patients were followed up for a minimum period of 1 year from the date of surgery. Assessment of post-operative aesthetic outcome, in terms of satisfaction, was done using the Visual Analogue Scale (VAS), which ranges from 1 to 10 by the patient and operative surgeon. Results: The mean age was 30.8 9.8 years. Out of 60 patients, 20 patients underwent additional procedure like dermabrasion and collagen dressing to improve aesthetic outcome. Among 60 patients, 24 patients had transient edema and 10 patients had bruising at the recipient site. There were no major donor site complications except pain which was managed conservatively. Mean patient satisfaction score is 7 and mean surgeon satisfaction score is 7.25. Conclusion: Despite the ongoing concerns about survival and longevity of fat grafts and also unpredictability of long-term outcomes, fat grafting has become a very useful surgical tool to improve the quality of facial scars and correct contour deformity. Our series shows excellent outcome both clinically as well as from the patient satisfaction. Future research is warranted in the fields of the adipocyte derived stem cells and to expand the clinical application of fat grafting.

A SCC-250 MeV cyclotron, producing a 250 MeV proton beam, is under development in Huazhong University of Science and Technology (HUST) for proton therapy. The magnetic flux density, as a function of radius, decreases rapidly in the beam extraction region, which increases the radial beam size continuously along the extraction orbit. In this paper, an extraction channel inside the SCC-250 MeV is designed to control the beam size using passive magnetic channels. An equivalent lumped parameter method is used to establish the model of the extraction channel in the complex fringe magnetic field of the main magnet. Then, the extraction channel is designed using the lattice design software MADX. The beam envelopes are verified using particle tracing method. The maximum radial size of 6.8 mm and axial size of 4.3 mm meet the requirements of the extraction from the SCC-250 MeV.

Background: While using radial forearm free flap in palate reconstruction, the pedicle lies in the nasal floor, constantly exposed to the nasal secretions and turbulent air current. To overcome this problem, we have designed a procedure which utilises the adipofascial extension to wrap the pedicle and nasal side of the flap. Materials and Methods: The study was done during 2017 and 2018, 2 years’ period. Totally 13 consecutive patients with defect in the palate status post-oncological resection and those in whom local flaps were not enough to cover the defect were included into the study. These patients were divided into two groups. First group in whom adipofascial extension was not used to cover the pedicle and second group in whom adipofascial extension was used to cover the pedicle. The incidence of nasal crusting, secondary haemorrage, blow out and flap necrosis were analysed and compared. Results: In Group 1, we had 2 among 6 (33%) patients with secondary haemorrage. One patient had partial flap loss. On exploring, we noticed thrombosis of cephalic vein. We did not had any incidence of blow out of the pedicle. In Group 2, none of the patients had any secondary haemorrage. All flaps healed well. On doing nasal endoscopy at 6 months of follow-up, all flaps showed complete mucosalisation at the nasal side. Conclusion: Use of adipofascial extension while planning a radial forearm free flap to cover the nasal side of the flap and pedicle in the nasal floor helps to reduce the nasal crusting and secondary haemorrhage.

A fast-switching, high-repetition-rate magnet and power supply have been developed for and operated at TRIUMF, to deliver a proton beam to the new ultracold neutron (UCN) facility. The facility possesses unique operational requirements: a time-averaged beam current of 40~$\mu$A with the ability to switch the beam on or off for several minutes. These requirements are in conflict with the typical operation mode of the TRIUMF cyclotron which delivers nearly continuous beam to multiple users. To enable the creation of the UCN facility, a beam-sharing arrangement with another facility was made. The beam sharing is accomplished by the fast-switching (kicker) magnet which is ramped in 50~$\mu$s to a current of 193~A, held there for approximately 1~ms, then ramped down in the same short period of time. This achieves a 12~mrad deflection which is sufficient to switch the proton beam between the two facilities. The kicker magnet relies on a high-current, low-inductance coil connected to a fast-switching power supply that is based on insulated-gate bipolar transistors (IGBTs). The design and performance of the kicker magnet system and initial beam delivery results are reported., Comment: 16 pages, 21 figures

This article describes the new primary proton beamline 1U at TRIUMF. The purpose of this beamline is to produce ultracold neutrons (UCN) for fundamental-physics experiments. It delivers up to 40 µA of 480 MeV protons from the TRIUMF cyclotron to a tungsten spallation target and uses a fast kicker to share the beam between the Center for Molecular and Materials Science and UCN. The beamline has been successfully commissioned and operated with a beam current up to 10 µA, facilitating first large-scale UCN production in Canada. This article describes the new primary proton beamline 1U at TRIUMF. The purpose of this beamline is to produce ultracold neutrons (UCN) for fundamental-physics experiments. It delivers up to 40 microA of 480 MeV protons from the TRIUMF cyclotron to a tungsten spallation target and uses a fast kicker to share the beam between the Center for Molecular and Materials Science and UCN. The beamline has been successfully commissioned and operated with a beam current up to 10 microA, facilitating first large-scale UCN production in Canada.

A novel method for producing a kind of light glass-mat- reinforced thermoplastic (GMT) sheets by using a pneumatic technique is presented. The tensile and flexural properties of produced light GMT sheets, with various lengths of glass fibers and PP content, were determined experimentally. Results of the experimental investigation show that the light GMT sheets are fully suitable for engineering applications.

Orbital floor fractures pose a grave threat for injury to the infraorbital nerve, resulting in the patient suffering from a disturbing paraesthesia. It is challenging for the operating surgeon to release and secure the entrapped nerve with reconstruction of the orbital floor. We present an interesting case of orbital floor fracture with entrapped infraorbital nerve, wherein we have decompressed the nerve and provided it, a new course.

In a fixed-field alternating-gradient (FFAG) accelerator, eliminating pulsed magnet operation permits rapid acceleration to synchrotron energies, but with a much higher beam-pulse repetition rate. Conceived in the 1950s, FFAGs are enjoying renewed interest, fuelled by the need to rapidly accelerate unstable muons for future high-energy physics colliders. Until now a 'scaling' principle has been applied to avoid beam blow-up and loss. Removing this restriction produces a new breed of FFAG, a non-scaling variant, allowing powerful advances in machine characteristics. We report on the first non-scaling FFAG, in which orbits are compacted to within 10 mm in radius over an electron momentum range of 12-18 MeV/c. In this strictly linear-gradient FFAG, unstable beam regions are crossed, but acceleration via a novel serpentine channel is so rapid that no significant beam disruption is observed. This result has significant implications for future particle accelerators, particularly muon and high-intensity proton accelerators. © 2012 Macmillan Publishers Limited. All rights reserved.

This paper is concerned with two-dimensional (r, θ) thermoelastic dynamic responses of a long functionally graded hollow cylinder subjected to asysmmetrical thermal and mechanical loads. The material properties, except the Poisson's ratio, are assumed to be temperature independent and vary exponentially and continuously in the radial direction. By means of finite difference method and Newmark method, the motion governing equations of the long FGM hollow cylinder are solved. Comparisons between this paper's results and the corresponding analytical results validate the proposed solution. In addition, the effects of the volume fraction, temperature boundary conditions on the hollow cylinder's deformations and stresses distributions are examined, and many other valuable thermoelastic dynamic characteristics are revealed.

Due to the combination of fixed magnetic field operation with strong focusing, non-scaling FFAGs have a significant potential for future particle accelerator applications. However, this technology has a number of unique features, which must be fully studied before this potential can be realised. To do this, a proof-of-principle non-scaling FFAG, called EMMA – Electron Model for Many Applications – has been constructed at the STFC Daresbury Laboratory in the UK. It has been designed by an international collaboration of accelerator scientists and engineers. It will demonstrate the principle of non-scaling FFAGs and be used to study the features of this type of accelerator in detail.

Midline cleft of the lower lip and mandible is an extremely rare condition. Since 1819, when the first case was reported by Couronne, fewer than 80 cases have been described in the world literature so far. The cleft has also been described as facial cleft no. 30 by Paul Tessier. The condition varies in severity from a mild variety in which there is a submucous cleft and notching in the lower lip to a severe variety, involving the tongue, floor of the mouth, mandible, absent hyoid, atrophic neck muscles, and sternum. In this case report, a female child having complete midline cleft of the lower lip and mandible, with bifid tongue stuck to the floor of the mouth, absent hyoid bone and flexion contracture band extending from the confluence of the tip of the tongue, floor of the mouth, cleft mandible to the manubrium sterni is described, with special emphasis on surgical planning and management.

The CELSIUS ring is equipped with a pellet target used as an internal target for experiments at the WASA-facility. The pellet target generates a stream of frozen hydrogen pellets, the size of which is now reduced to 25–30 μm. We discuss the interaction between the pellet target and the stored beam under the influence of RF and electron cooling in terms of measurements and computer simulations. Energy loss measurements using Schottky spectra were performed to measure the effective pellet target thickness. We present Monte Carlo tracking simulations including the beam–target interaction as well as RF and electron cooling. The general behaviour is reproduced but the simulations overestimate the beam lifetime compared to observations.

HIRFL-CSR, a new ion Cooler-Storage-Ring (CSR) project, is the post-acceleration system of the Heavy Ion Research Facility in Lanzhou (HIRFL). It consists of a main ring (CSRm) and an experimental ring (CSRe). From the HIRFL cyclotron system the heavy ions will be accumulated, cooled and accelerated in the CSRm, then extracted fast to produce radioactive ion beams (RIB) or highly charged heavy ions. Those secondary beams will be accepted and stored by the CSRe for many internal-target experiments with electron cooling.

This paper is devoted to the simulation of electron cooling and intrabeam scattering processes of a heavy ion beam in the proposed HIRFL-CSR, according to the analytical cooling force formulae and the intrabeam scattering growth rate expressions. Some important effects like the betatron and synchrotron oscillations, and space charge effect of the electron beam have been considered. Time evolution of beam emittances and momentum spread under joint action of the electron cooling and intrabeam scattering are shown. The dependence of ion beam properties in equilibrium on the number of particles and the electron current are presented.

Adenosine deaminase and protein tyrosine phosphatase activities in liver and peritoneal macrophages were estimated in control, streptozotocin induced diabetes and insulin treated diabetic groups of Swiss albino mice. Both the enzyme levels were elevated while glycogen content decreased in the liver of diabetic group of animals as compared to controls, while in insulin treated group, they were comparable to control levels. In macrophages also, both adenosine deaminase which plays an important role in their maturation and protein tyrosine phosphatase enzyme involved in their activation were high in diabetic group, whereas in insulin treated diabetic group, the values were comparable to control levels. *** DIRECT SUPPORT *** A00FN011 00003

This chapter introduces fields of application for the cyclotron, some speculative, and gives illustrations of activity in some older fields of application. It describes some cyclotron technology and contains a discussion of the factors that may limit the intensity of the beam from cyclotrons. Keywords: cyclotrons; accelerators; radioisotopes

The 2A beamline, one of the TRIUMF cyclotron primary extraction beamlines, is 60 m in length. It is now routinely operating up to 70 uA (proton beam) at 500 MeV for ISAC. ISAC requires a diffuse spot of specific size on the radioactive beam production target at the end of 2A. To help achieve this, we developed a program aimed at obtaining a better understanding and more accurate description of 2A optics and the extracted beam from the cyclotron. The beam sizes along 2A were measured with profile monitors and compared with theoretical predictions. During the course of this work, we discovered that the transfer matrix, involved in the optics calculations, between the stripping foil and the beamline entrance was incorrect. After correcting this error, we obtained good agreement between the measured and calculated envelopes. We report on the details of this work as well as on a measurement of the beam characteristics as a function of stripper foil thickness.

Coronary artery disease is a major cause of morbidity and has various risk factors. Lipid profile i.e. low HDL-cholesterol, high LDL cholesterol, high total cholesterol, high triglycerides playing important role in its causation. Recently interest has been shown in the oxidized fraction of LDL as one of the risk factors. In the present study 60 age and sex matched normal healthy individuals were taken as controls and 60 patients of CAD were taken. Cholesterol was measured by enzymatic method, HDL cholesterol by phosphotungstate precipitation method. Serum levels of LDL fraction of cholesterol was measured by a new and simpler method of precipitation. Result was expressed as mol/L of diene conjugates. It was observed that LDL cholesterol, VLDL cholesterol, total cholesterol, total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol were significantly raised and HDL cholesterol was significantly low in patients. (p

The present situation of the low energy probe LE2 in TRIUMF cyclotron is that the thickness of the finger 5 is uniform over a radial length of 3.25 inch and its weight which amounts to ∼ 447 g is affecting its re-circulating ball mechanism and causing it to fall below the median plane over its range of movement. We therefore re-design it in order to reduce its weight. First, we made simulations and determined the optimum thickness of the probe head vs its radial length. These simulation results are found to be in good agreement with experimental measurements made. Finally, we calculated the temperature rise caused by the beam power dumped on the probe, and figured out the maximum current of beam that can be dumped on the finger.

In the actual operation of the storage ring CELSIUS with the hydrogen pellet target, we sometimes observe a cooling phenomenon in the longitudinal phase space, that is, the circulating beam’s rf phase width gets shrunk instead of blown up. This phenomenon occurs independently on the electron cooling. In this paper we intend to study and interpret this phenomenon as well as the beam lifetime in the presence of hydrogen pellet target with and without rf and with and without electron cooling by using Monte Carlo simulations [1].

In this report two diagnostic methods for a neutralised electron beam on the JINR test bench are presented and compared: the time of flight method and the pencil beam method.

The TRIUMF cyclotron operates routinely at 200 /spl mu/A extracted at 500 MeV. Because of growing demands for beam, up to 400 /spl mu/A is envisaged: this would require /spl sim/ 1 mA from the H/sup -/ ion source and injection beamline. The phase acceptance of the cyclotron is roughly 36/spl deg/, so the local peak beam current just before injection would be higher than 4 mA. This leads to large space charge effects on the beam transverse envelope and longitudinal bunching efficiency. The beam profiles and the bunching efficiency were measured for different currents up to 575 /spl mu/A . These were used in space charge transport calculations to determine the beam optic properties and the space charge neutralization level. Extending the calculations to higher intensities, it is found that with the present double drift double harmonic bunching system, the bunching efficiency decreases dramatically above a dc current of 600 /spl mu/A . To enable reaching the envisaged 400 /spl mu/A from the cyclotron, it requires either raising the cyclotron phase acceptance from the present /spl sim/ 36/spl deg/ to 50/spl deg/ by for example increasing the energy gain per turn at injection, or by adding another fundamental harmonic buncher.

A new series of experiments (mainly astrophysics) began at TRIUMF in July 2001 when the ISAC-I linear accelerator began delivering up to 1.5 MeV/u radioactive ion beams (RIB) to users. A superconducting linear accelerator extending the RIB energy to 6.5 MeV/u has recently been approved and is now being constructed (ISAC-II). Record RIB intensities are being achieved from different target ion sources with a primary incident proton beam of 500 MeV, up to 50 /spl mu/A intensity. This will later be increased to 100 /spl mu/A, compatibly with target acceptance. Furthermore, an additional 100 /spl mu/A extracted proton beam is being considered for simultaneous (RIB) production from a second target-ion source system. This would significantly enhance the research potential of the laboratory. Four simultaneous high-intensity extracted beams would therefore be required for a total maximum cyclotron accelerated current of about 400 /spl mu/A. Recently we have been able to deliver 300 /spl mu/A to the existing three high intensity beam lines at 90% duty cycle. The cw delivery of beam was limited only by the presently available external beam dump capacity. In this paper we will review the present operational experience at 200/250 /spl mu/A, the future plans for intensity upgrade to 350/400 /spl mu/A, and the intrinsic factors limiting the total accelerated intensity beyond 400 /spl mu/A.

A biochemical study consisting of estimation of serum adenosine deaminase and ascorbic acid was carried out in 20 patients of recurrent tonsillitis (i) during the acute attack, (ii) after medical treatment and (iii) after tonsillectomy. These parameters were compared with a control group of 20 healthy individuals. The study revealed significant decrease of ADA and ascorbic acid levels during acute stage of recurrent tonsillitis, and subsequent recovery after medical treatment and tonsillectomy. Levels of ascorbic acid were similarly reflected. In the acute stage of recurrent tonsillitis, tonsils, instead of acting as protective barriers, appear to become a source for the breakdown of immunological mechanism.

To determine the effect of timing of cord clamping on iron stores of term infants at 3 months of age.Prospective randomized clinical trial.Tertiary hospital.107 term neonates born to mothers with uncomplicated pregnancies and with hemoglobin more than 10 g/dl.The 107 infants were randomized to either early (n = 48) or late (n = 59) clamping groups at the time of delivery. Outcome measures evaluated were serum ferritin and hemoglobin in the infant at 3 months age.The groups were comparable for maternal age, parity, weight, supplemental iron intake in pregnancy, infant's birth weight, gestation and sex. Maternal and cord ferritin and hemoglobin values at birth were comparable. The infant ferritin at 3 months were also similar.Iron stores at 3 months in term infants are not influenced by timing of cord clamping at birth.

To assess the oxidative stress across the cell membrane in patients suffering from pregnancy induced hypertension, erythrocyte malonyldialdehyde, vitamin E, reduced glutathione, glucose-6-phosphate dehydrogenase activity and plasma urate levels were estimated in 25 non pregnant women, 40 normotensive pregnant women and 40 women with pregnancy induced hypertension (PIH). As compared to non pregnant women, there was a significant increase in the levels of erythrocyte malonyldialdehyde and plasma urate in normotensive pregnant women, which were further increased in women with PIH. Erythrocyte glutathione levels were raised in normotensive pregnant women as compared to non pregnant women. Its levels were decreased in patients of PIH as compared to normotensive pregnant women. Cellular bio-availability of vitamin E was depressed in both normotensive pregnancy as well as patients with pregnancy induced hypertension as compared to non pregnant women.

Six serum enzymes, alkaline phosphatase, cholinesterase, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transpeptidase were studied in 30 cases of protein energy malnutrition (PEM). The mean serum values of alkaline phosphatase, cholinesterase and lactate dehydrogenase in cases of PEM were significantly lower than the controls, lowering being maximum in PEM Grade IV. The mean serum values of aspartate aminotransferase and alanine aminotransferase in patients with PEM were significantly higher than the controls. The mean serum values of gamma-glutamyl transpeptidase showed similar significant rise in all but PEM Grade IV. The degree of increase in the serum values of these three enzymes were maximum in cases with PEM Grade I. These findings suggest that abnormalities in blood levels of these enzymes occur in any form of PEM and these are related to the severity of the disease.

Effect of different doses (2.5 mg, 5 mg, 10 mg and 40 mg/kg), s.c., for 2 weeks, of cyproheptadine (CYP) on brain cholesterol and phospholipid of albino rats was investigated. Cyp. 2.5 mg/kg, showed increase in brain cholesterol and phospholipid contents whereas other doses caused a decrease in phospholipid level.

An isolate of Getah virus was obtained from Culex mosquitos collected in Mao'an Village, Baoting County, Hainan Province, China, in 1964. The virus (strain M-1) replicated in laboratory-bred Aedes aegypti and Cx. fatigans (= quinquefasciatus), and was transmitted by laboratory-bred Ae. albopictus to healthy newborn albino mice. Skeletal muscles of newborn albino mice experimentally infected with the virus showed degeneration, atrophy, necrosis, and inflammatory changes of muscle fibers. Antibody prevalence in humans and animals ranged from 10.3% by neutralization tests of samples from healthy people in 1979 to 26.4% by CF tests of samples from people with febrile illnesses in 1982. The high prevalence of antibody in pigs, horses, and goats (17.6% to 37.5%) indicated that infection with Getah or a closely related virus is relatively common in domestic animals.

This paper describes novel Point-to-Point TTL (PPTTL™) architecture between timing controller and source driver ICs. The application of PPTTL will be verified 15.4″ WXGA prototype TFT LCD panel with 2layer PCB layout. The advantage of PPTTL includes low cost, low power consumption, and low EMI radiation ect. Also PPTTL is suitable for COG package even large size panel.

Estimation of net primary production (NPP) of intertidal seaweeds by the harvest method is beset with a number of problems, prominent among which is the lack of a method to quantify precisely the dead and decaying parts, as these two fractions do not accumulate in situ, but get washed away and cast ashore. In the light of this, while presenting the results of NPP of 3 intertidal seaweeds from Veraval on the western coast of India, the merits and demerits of different methods adopted hitherto are discussed.

The results of experimental investigations on the anomalous breakdown characteristics of polymethyacrylate (PMMA) immersed in transformer oil are reported in this paper. The insulation was subjected to a combination of direct and impulse voltages. The anomalous breakdown voltage was found to decrease when the polarity of superimposed impulse voltage was opposite to that of the direct voltage and to increase when the polarities of both are the same. The polarity of the resultant appled voltage was also found to affect the length of the breakdown path. An attempt is made to explain such anomalous behavior with the help of space charge accumulation in modern synthetic insulating materials. The variation of direct voltage prestress time on the anomalous breakdown voltage are also discussed. Copyright ? 1982 by The Institute of Electrical and Electronics Engineers, Inc.

Les resultats des effets de la temperature de l'air, de l'humidite relative et de la vitesse du vent sur la biomasse des trois agarophytes suivants: Gracilaria corticata, Gelidium pusillum et Hypnea musciformis

The relative photosynthetic rates of fronds of Ulva lactuca Linn. (Ulvales, Chlorophyceae) sampled from upper, middle and lower littoral zones, were measured when submerged and at different levels of desiccation under laboratory conditions. The upper and middle littoral fronds showed increased rates of photosynthesis under exposure to air but the lower littoral ones showed maximal rates under submergence and registered lower rates under exposure. The rates of the upper littoral fronds were significantly higher than those of lower ones, under desiccated conditions. The upper ones had higher moisture content than the middle and lower littoral fronds during submergence but they were fast to lose their moisture under desiccation. The moisture levels at which the photosynthetic rates began to fall were 45%, 72% and 100%, in the upper, middle and lower littoral fronds, respectively. It is inferred from this study that the upper littoral fronds of the species, which are subjected to longer periods of exposure and consequently more desiccation during emergence in nature, are better adapted to emerged conditions than the lower ones. The results further suggest that the three types of fronds could be locally adapted ecads or ecotypes, the differences being the outcome of their responses to the physical conditions operating along the intertidal belt. Key-words: Ulva lactuca, intertidal, seaweeds, desiccation, photosynthesis, ecad, ecotype, submergence, emergence