Brachistochrone on a velodrome

The Brachistochrone problem, which describes the curve that carries a particle under gravity in a vertical plane from one height to another in the shortest time, is one of the most famous studies in classical physics. There is a similar problem in track cycling, where a cyclist aims to find the trajectory on the curved sloping surface of a velodrome that results in the minimum lap time. In this paper, we extend the classical Brachistochrone problem to find the optimum cycling trajectory in a velodrome, treating the cyclist as an active particle. Starting with two canonical cases of cycling on a sloping plane and a cone, where analytical solutions are found, we then solve the problem numerically on the reconstructed surface of the velodrome in Montigny le Bretonneux, France. Finally, we discuss the parameters of the problem and the effects of fatigue.

Effect of selection on ancestry: an exactly soluble case and its phenomenological generalization

We consider a family of models describing the evolution under selection of a population whose dynamics can be related to the propagation of noisy traveling waves. For one particular model that we shall call the exponential model, the properties of the traveling wave front can be calculated exactly, as well as the statistics of the genealogy of the population. One striking result is that, for this particular model, the genealogical trees have the same statistics as the trees of replicas in the Parisi mean-field theory of spin glasses. We also find that in the exponential model, the coalescence times along these trees grow like the logarithm of the population size. A phenomenological picture of the propagation of wave fronts that we introduced in a previous work, as well as our numerical data, suggest that these statistics remain valid for a larger class of models, while the coalescence times grow like the cube of the logarithm of the population size.

Phenomenological theory giving the full statistics of the position of fluctuating pulled fronts

We propose a phenomenological description for the effect of a weak noise on the position of a front described by the Fisher-Kolmogorov-Petrovsky-Piscounov equation or any other traveling-wave equation in the same class. Our scenario is based on four hypotheses on the relevant mechanism for the diffusion of the front. Our parameter-free analytical predictions for the velocity of the front, its diffusion constant and higher cumulants of its position agree with numerical simulations.

Immunosensors for pollutants working in organic media. Study of performances of different tracers with luminescent detection

A comparative study of enzymatic and non-enzymatic labels combined with luminescence detection, developed for immunosensing of pesticide residues (carbaryl, 1-naphthol, irgarol 1051) in organic media, is presented. Peroxidase and alkaline phosphatase enzymes with fluorogenic (3-p-hydroxyphenylpropanoic acid) and luminogenic (AMPPD derivative) substrates, respectively, were assessed as enzymatic markers. As an alternative, terbium(III) chelate, with time-resolved fluorescence detection, was evaluated as a non-enzymatic label. The best sensitivity was achieved by use of alkaline phosphatase in an immunocomplex capture assay format (I (50) values 0.06, 0.27, and 7.45 microg L(-1) in buffer, 1:1 methanol-buffer, and methanol, respectively). Results were also good (I (50) 1.00 and 6.30 microg L(-1) for water and aqueous-organic mixture, respectively) for Tb(III) chelate in an immobilized conjugate assay format. Use of alkaline phosphatase label to measure carbaryl (100 ng L(-1)) in different spiked river water samples, after solid-phase extraction and analyte elution with an ethyl acetate-methanol mixture, resulted in recoveries ranging from 81 to 98%, with acceptable precision (CV 4-14%, n=4).

Double-blind randomized evaluation of clinical and biological tolerance of polyethylene glycol 4000 versus lactulose in constipated children

OBJECTIVES

To assess the safety of a polyethylene glycol (PEG) 4000 laxative without additional salts in pediatric patients.

STUDY DESIGN

This was a 3-month multicenter, randomized, double-blind, double-dummy, lactulose-controlled, parallel study enrolling 96 ambulatory constipated children aged 6 months to 3 years, treated daily with 4-8 g PEG or 3.33 g-6.66 g lactulose. Total protein, albumin, iron, electrolytes, and vitamins B9 (folates), A and D (25OHD3) were measured in blood before and after treatment (day 84) in a central laboratory.

RESULTS

The percentage of children with at least one value out of normal range at day 84 with respect to baseline status (with or without at least one value out of normal range), i.e. the primary endpoint, was 87% and 90% in the PEG and lactulose groups, respectively, without any difference between groups. The whole blood parameters showed no qualitative or quantitative treatment-related changes. Vitamin A values were above normal range in 56% and 41% of children at baseline versus 33% and 36% at day 84 in the PEG and lactulose groups, respectively. Iron values were similarly under normal range in 47% and 51% at baseline versus 42% and 51% at day 84. Clinical tolerance was similar for both treatments except for vomiting and flatulence, which were significantly higher with lactulose. Significantly higher improvements were evidenced with PEG regarding stool consistency, appetite, fecaloma and use of additional laxatives.

CONCLUSION

This 3-month study in 96 constipated children aged 6 months to 3 years confirms the long-term tolerance of PEG 4000 in pediatrics and indicates a PEG efficacy similar to or greater than that of lactulose.

Improving agglutination tests by working in microfluidic channels

Latex agglutination tests are used for the diagnosis of diseases in man and animals. They are generally simple, cheap, and do not require sophisticated equipment, nor highly specialized skills. In this Technical Note, we put latex agglutination tests in a microfluidic format. The experiment is performed in PDMS (polydimethylsiloxane) microchannels, using streptavidin-coated superparamagnetic beads and a magnetic field. The target molecule is biotinylated protein A. By taking full advantage of the microfluidic conditions (scaling down of the detection volume and controlled action of the shear flow), we achieved an analytical sensitivity of 10 fmol l(-1)(several hundreds of fg ml(-1)) and a fast response (a few minutes) ; the test is also quantitative. Performances of agglutination tests can thus be improved by orders of magnitude by adapting them to a microfluidic format; this comes in addition to the usual advantages offered by this technology (integration, high throughput etc.).

Binding properties of the conjugates of oligo(2'-O-methylribonucleotides) with minor groove binders targeted to double stranded DNA

Design, synthesis, physico-chemical and in vitro biological studies of new pyrimidine oligo(2'-O-methylribonucleotide) conjugates with oligocarboxamide minor groove binders (MGB) and benzoindoloquinoline intercalator (BIQ) are described. These conjugates formed stable triple helices with the target double-stranded DNA and inhibited its in vitro transcription upon binding.

Aggregation of paramagnetic particles in the presence of a hydrodynamic shear

We present an experimental study of the aggregation of paramagnetic particles, in the presence of controlled laminar shear flow, conducted in microchannels subjected to an external magnetic field. The microfluidic channels are made of either glass/silicon or polydimethylsiloxane. In ranges of time up to hundreds of seconds, the growth mechanism of the linear chain consists of the accumulation of isolated particles or small clusters onto existing chains, which are all moving at different speeds. In this time regime the chain length increases linearly and has a growth rate that increases as a power law with the shear. At longer times the chain lengths saturate. The Smoluchovski model, which assumes single particle-chain interactions only, closely reproduces the observations both qualitatively and quantitatively. In particular, the evolution of the growth rate of the mean chain length with respect to the shear rate S, predicted as S1/4, is found to be consistent with the experiments.

Multiple glioblastomas: CT and MR features

The aim of this study was to analyze the CT and MR features of multiple glioblastomas, and to determine the best imaging modality for the initial diagnosis. The CT (four exams) and MR imaging (eight exams) of eight patients with proven multiple glioblastomas were reviewed by two neuroradiologists. The lesions were always hypo- or isodense on CT and hyperintense on T2-weighted images (100%). They were usually hypo- or isointense on T1-weighted images (90%). Edema and mass effect were very variable. After contrast media administration, the enhancement was mostly strong (71% on CT and 70% on MR), often either heterogeneous or ring-like. The different lesions of a patient often had a different pattern on MR (75% of cases). Meningeal or ventricular enhancement, suggestive of a possible way of dissemination, was rare. In case of multiple cerebral masses, multiple glioblastomas should be considered as a possible diagnosis in addition to the better known diagnosis of brain metastases, abscesses, or multifocal lymphomas. Moderate edema and mass effect on MR associated with strong and heterogeneous enhancement are suggestive of feature of multiple glioblastomas. Magnetic resonance allows rarely the visualization of a dissemination route.

Luminescent cryptands. 3-aroylcoumarin macrobicyclic complexes of europium(III) and terbium(III): the effect of coumarin substitution

Substituted 3-aroylcoumarins incorporated in a polyethylenoxy cryptand (2.2.2) by the 3-aroyl group were synthesized with the purpose of developing new markers to be used in time-resolved fluorimetric bioaffinity assays based on the unique luminescence properties of Eu(III) and Tb(III) ions. Some spectral properties and luminescence intensities of the complexes were measured in acetonitrile and MeOH. The mechanism of metal sensitization depended on lanthanide and will be discussed in detail.

DEA: An architecture for goal planning and classification

We introduce the differential efficiency algorithm, which partitions a perceptive space during unsupervised learning into categories and uses them to solve goal-planning and classification problems. This algorithm is inspired by a biological model of the cortex proposing the cortical column as an elementary unit. We validate the generality of this approach by testing it on four problems with continuous time and no reinforcement signal until the goal is reached (constrained object moves, Hanoi tower problem, animat control, and simple character recognition).

Probability distribution of the free energy of a directed polymer in a random medium

We calculate exactly the first cumulants of the free energy of a directed polymer in a random medium for the geometry of a cylinder. By using the fact that the nth moment <Z(n)> of the partition function is given by the ground-state energy of a quantum problem of n interacting particles on a ring of length L, we write an integral equation allowing to expand these moments in powers of the strength of the disorder gamma or in powers of n. For n small and n approximately (Lgamma)(-1/2), the moments <Z(n)> take a scaling form which allows us to describe all the fluctuations of order 1/L of the free energy per unit length of the directed polymer. The distribution of these fluctuations is the same as the one found recently in the asymmetric exclusion process, indicating that it is characteristic of all the systems described by the Kardar-Parisi-Zhang equation in 1+1 dimensions.

A PET investigation of the attribution of intentions with a nonverbal task

Several authors have demonstrated that theory of mind is associated with a cerebral pattern of activity involving the medial prefrontal cortex. This study was designed to determine the cerebral regions activated during attribution of intention to others, a task which requires theory-of-mind skills. Eight healthy subjects performed three nonverbal tasks using comic strips while PET scanning was performed. One condition required subjects to attribute intentions to the characters of the comic strips. The other two conditions involved only physical logic and knowledge about objects' properties: one condition involved characters, whereas the other only represented objects. The comparison of the attribution of intention condition with the physical logic with characters condition was associated with rCBF increases in the right middle and medial prefrontal cortex including Brodmann's area (BA) 9, the right inferior prefrontal cortex (BA 47), the right inferior temporal gyrus (BA 20), the left superior temporal gyrus (BA 38), the left cerebellum, the bilateral anterior cingulate, and the middle temporal gyri (BA 21). The comparison of the physical logic with characters condition and the physical logic without characters condition showed the activation of the lingual gyri (BA 17, 18, 19), the fusiform gyri (BA 37), the middle (BA 21) and superior (BA 22, 38) temporal gyri on both sides, and the posterior cingulate. These data suggest that attribution of intentions to others is associated with a complex cerebral activity involving the right medial prefrontal cortex when a nonverbal task is used. The laterality of this function is discussed.

[Vertebro-epidural lumbosacral vascular malformations. An unusual cause of lumbo-sciatic pain]

Sciatica is most commonly caused by nerve root compression secondary to herniated disk. Rarely, it can be due to a lumbosacral vascular malformation. We present five cases with such a malformation, presenting as a chronic lumboradiculagia. The patients were explored with computed tomography, MRI and selective spinal angiography. Polymorphic anatomic and hemodynamic aspect of these cases are reported: 1. One vertebral hemangioma with epidural extension; 2. Three purely epidural malformations: a) one epidural cavernous hemangioma, b) one epidural arteriovenous malformation, c) one epidural varix; 3. One paravertebral arteriovenous fistula with epidural venous drainage. Diagnosis of these rare malformations may be difficult. A multiplanar cross-sectional magnetic resonance and computed tomography scan with contrast enhancement can show characteristic abnormalities and may assist in recognition these malformations. Selective spinal angiography confirms the diagnosis, allows to classify the malformation and is required to evaluate endovascular therapeutic possibilities.

Shaping Solid-State Supramolecular Cavities: Chemically Induced Accordionlike Movement of gamma-Zirconium Phosphate Containing Polyethylenoxide Pillars

The hydrophilic oxygen atoms of polyethylenoxide chains inserted as pillars in gamma-zirconium phosphate form hydrogen bonds with the acid groups of the host. As a result the pillars are almost perpendicular to the gamma layers. Upon changing the pH level of the supernatant solution the hydrogen bonds are broken and the pillars become almost perpendicular to the layers (shown schematically). Thus there is a reversible enlargement-shortening of the interlayer space.

Investigating theory of mind in schizophrenia: influence of verbalization in disorganized and non-disorganized patients

The ability to attribute intentions to others was studied in 13 disorganized and 13 non-disorganized schizophrenic patients, 13 depressed and 13 normal controls. Subjects were asked to complete 28 comic strips requiring theory of mind skills by choosing one out of three answer cards. The answer cards were simple pictures in a first condition and short sentences in a second condition. This study, which used the cognitive neuropsychological approach, underlies the existence of a link between disorganization patterns in schizophrenia and a deficit in the attribution of intentions to others, independently of the pictorial or verbal form of the mode of answering. In addition, results show that the non-disorganized schizophrenic group, depressed and normal controls perform similarly in both pictorial/verbal conditions. The influence of the absence/presence of verbal material on a task investigating theory of mind in schizophrenia is discussed.

[Intracranial dural arteriovenous fistula with perimedullary venous drainage]

Two cases of intracranial dural arterio-venous fistula (DAVF) with perimedullary venous drainage are reported. In both cases, MRI T2-weighted (T2W) images showed an hypersignal within the cervical cord with sparing of the thoracic cord. In one case perimedullary vessels were demonstrated on T1W images after gadolinium i.v. administration. A complete spinal angiogram did not show evidence of fistula but demonstrated the lack of opacification of the conus medullaris venous drainage. Cerebral angiogram demonstrated in the first case a foramen magnum DAVF and in the second case a petrous apex DAVF. Hypersignal limited to the cervical cord at MRI on T2W images remain exceptionnal in case of intracranial DAVF with perimedullary venous drainage. When neurological symptoms are suggestive, post gadolinium T1W sequences should be conducted, followed by selective spinal angiogram. If normal venous drainage is not objectivated (e.g. opacification of radiculo-medullary veins on the late phase), cerebral angiogram should be done to rule out an intracranial DAVF.

[Percutaneous vertebroplasty of the cervico-thoracic junction using an anterior route. Technique and results. Report of nine cases]

Percutaneous vertebroplasty using fluoroscopy is a well known technique. Visualization of the posterior wall of the vertebra is mandatory. Good assessment of this part of the vertebra is usually difficult at the cervico-thoracic junction. We propose an original method to obtain adequate visualization of the posterior wall, avoiding the shoulders superposition. Using this technique, we performed twelve vertebroplasties in nine patients (one angioma and eleven metastatic lesions). Clinical outcome was good for all patients, even a total filling of the vertebra body by the cement was obtained in only eight cases on twelve. No clinical complication was observed.

[The nasopharynx and deep spaces of the face: anatomy and applications to pathology]

Deep facial spaces are anatomically delineated by the layers of deep cervical fascia. They are located between the skull base and the hyoid bone. Each space contains specific anatomic structures, which can be responsible for specific pathologic processes. Deep facial spaces can be divided in two medial odd spaces (pharyngeal mucosal and retropharyngeal spaces), and in three lateral even spaces (retrostylian, prestylian, and masticator spaces). The dividing of these core tissues are useful for the analysis of the lesions found in this area. CT scan and MRI (with axial and coronal views) provide precise analysis. The main lesions are: -medially, adenoidal hyperplasias and squamous cell carcinomas (pharyngeal mucosal space), adenopathies and abscess (retropharyngeal space). -laterally, salivary tumors (prestylian space), adenopathies, schwannomas and paragangliomas (retrostylian space). Masticator space (and especially pterygopalatine fossa) is an important way of communication and is often involved by the extension of locoregional pathologic processes.

[The contribution of "time-of-flight" MRI-angiography in the study of neurovascular interactions (hemifacial spasm and trigeminal neuralgia)]

The purpose of this study was to investigate capabilities of Magnetic Resonance Angiography (MRA) in delineating neurovascular compression which has emerged as the most frequent etiology in cases of Hemi-Facial Spasm and Trigeminal Neuralgia. MR investigations were carried out at 1.5 t unit (Magnetom Vision, Siemens). The examination consisted of 3D time-of-flight MRA (3d TOF) protocol, with a FISP sequence (Fast Imaging Steady Precession) and magnetization transfer. Imaging parameters were; TR 39 ms, TE 7 ms; MX 256-512; FOV 210-210 mm. Time acquisition is 10 mm 30 s. The axially acquired angiographic slices were reformatted with a multiplanar reconstruction program (MPR) along and across the plane of facial and trigeminal nerves. Then millimetric raw data images were postprocessed with a maximum intensity projection (MIP) technique. 58 patients presented either with hemifacial spasm (36 cases, 16 women, 20 men, mean age: 58.5 y) or trigeminal neuralgia (22 cases, 13 women, 8 men, mean age: 51 y) were compared with 17 patients (9 women, 8 men, mean age: 57.5 y) as references. MRA with MIP and MPR techniques reliably demonstrates neurovascular compression at the root entry zone (REZ), and allows recognition of the implicated vascular loop in 34 the cases of hemifacial spasm investigated. Raw data were post-processed in an axially oblique plane parallel to the acoustico-facial bundle and secondarily reconstructed in coronally obliques views. These reconstructed images clearly delineate the cross-compression of the emerging facial nerve. The neurovascular conflict was related to an arterial loop from the postero-inferior cerebellar artery (PICA, 21 cases, 61%) and the antero-inferior cerebellar artery (AICA, 8 cases, 23%). Vertebral artery is implicated in conflicts in 5 cases. In 2 cases MRA exploration was negative. In HFS group distance between Vth nerve emergency and neuro vascular contact was measured and compared with control group; there is a significative difference (p < 0.01). In case of trigeminal neuralgia, MRA demonstrates neurovascular compression at the root entry zone of the Vth nerve of 16 patients. In theses cases, oblique and coronally reconstructed images are crucial in demonstrating neurovascular contacts. The vessel implicated in conflict is always the superior cerebellar artery (SCA). A supero-medial loop of the superior cerebellar artery was depicted in these 16 cases. Although 3 patients had negative MRA and MR studies, a case of compression of the origin of the Vth nerve by a enlarged draining vein in a case of brainstem arterio-venous malformation, a petrous apex meningioma was incidentally discovered and thoroughly investigated with gadolinium T1 weighted sequences and 1 demyelinating plaques located along the intraaxial course of the Vth nerve were noticed. In control group on 34 explanations only there are only 4 contacts between Vth nerve and SCA. MRA with a 3D-TOF FISP sequence allows recognition of neurovascular conflicts in case of hemifacial spasm and trigeminal neuralgia while MIP helps to characterize the implicated vessel. Sources images need to be carefully assessed in order to depict unsuspected pathology.

[MRI of degenerative extrapyramidal syndromes. Parkinson disease, progressive supranuclear palsy and multiple system atrophy]

MR imaging of the brain, particularly with high field MR imagers, may demonstrate signal abnormalities consistent with deposits of iron or other paramagnetic substances in extrapyramidal disorders. The diagnosis of Parkinson's disease and progressive supranuclear palsy can be made on clinical grounds in most of the cases and MR signs are of little help in the diagnosis of these diseases. In patients with parkinsonian disorders poorly responding to therapy, MR imaging may be useful in demonstrating signal abnormalities in the putamen that may help to establish the diagnosis of striatonigral degeneration (component of multiple system atrophy) with a poorer prognosis than Parkinson's disease. Finally, MR imaging may be useful in the exclusion of other disease processes.

Preschool vision testing with a new device, the Scolatest

To determine the reliability of results obtained in preschool children by school nurses with a new device for testing vision, the Scolatest, 153 children aged 4 to 5 years were presented with the Snellen E on the standard American Optical projector and with five letters of the Sheridan test (H, O, V, T and X) on the Scolatest. Another 212 children aged 3 to 4 years were presented with the Allen symbols on the projector and with the Pigassou symbols on the Scolatest. The tests with the projector were given at 6 m by an experienced pediatric orthoptist, those with the Scolatest at 2.5 m by a school nurse. The proportion of good responses was higher with the Pigassou symbols than with the Allen symbols. The results with the Sheridan letters and the Snellen E were similar up to 20/30; beyond 20/30 the Snellen E appeared unreliable. The four vision-testing systems were also presented by a school nurse at 2.5 m on the Scolatest to 102 children aged 4 to 5 years (Snellen E and the five Sheridan letters) and 80 children aged 3 to 4 years (Allen and Pigassou symbols). The proportions of good responses were more comparable. The results suggest that a working distance of 2.5 m should be used in testing vision in preschool children. Visual screening at this distance should test acuity beyond the 20/30 equivalence if results comparable to those at 20 feet with the 20/30 standard requirement are to be obtained.

In vivo time course of synthesis and processing of major schizont membrane polypeptides in Plasmodium falciparum

A rapid method of separating membrane co-sedimentable and soluble components of Plasmodium infected erythrocytes is presented. We propose a nomenclature for major P. falciparum polypeptides, applicable to different isolates and based on their cellular location and stage specificity. For four of these polypeptides (185 kDa = Mp1; 120 kDa = Mp3; 76 kDa = Mp5; 90 kDa= Sp2) supposed to play a role in protective immunity, monospecific antibodies were available. We have studied their fate at the time of merozoïte release and reinvasion, and the possible correlations between these polypeptides, by pulse-chase experiments.

Cloning of cDNAS that code for Plasmodium chabaudi antigens of the erythrocytic forms and cross-hybridize with P. falciparum

Several Plasmodium chabaudi antigens are synthesized and the corresponding mRNAs are detected by cell-free translation only during specific stages of the erythrocytic cycle. Ring stage mRNA was used to construct a cDNA library in the plasmid vector pBR 322. The library was screened by differential hybridization with cDNA specific for ring stage parasites or schizonts. Two clones which showed some stage specificity and seven which did not were retained. Three clones were characterized by hybrid-selected translation. Clones 451, 148 and 443 contain sequences homologous to the messages for a 27 kDa stage-specific antigen, a 37 kDa early antigen and a 24 kDa antigen, respectively. The nine clones cross-hybridize to various degrees with cDNA from P. falciparum but cross hybridization intensities do not reflect the strength of immunological cross-reactivity.

Destruction of Leishmania mexicana amazonensis amastigotes within macrophages in culture by phenazine methosulfate and other electron carriers

Exposure of macrophages infected with Leishmania mexicana amazonensis to phenazine methosulfate (PMS) resulted in rapid damage and disappearance of the intracellular amastigotes without obvious ill effects to the host cells. The reduction of the percent infection was related to the concentration of PMS and to the duration of the pulse. Most Leishmania disappeared within 2 h of a 2-h pulse with 10 muM of the drug. In contrast, pretreatment of the macrophages with PMS followed by removal of the drug before infection did not result in disappearance of the parasites. The pH of the PMS medium markedly influenced the disappearance of Leishmania: maximum effect was observed at pH 8.0, while the effect was negligible at pH 6.3. The pH effect may be related to pseudobase formation by the PMS cation. Dose-response curves for PMS were similar for resident, elicited, or activated macrophages. Observations by time-lapse cinemicrography documented the explosion-like fragmentation of the amastigotes within 1-2 h of exposure of infected macrophages to the drug. Parasite-derived granules and vacuoles were seen to scatter within the parasitophorous vacuoles. This early damage to the parasites was confirmed by transmission electron microscopic observations. Infected macrophages incubated with PMS displayed detectable vacuolar fluorescence, indicating that PMS or a metabolite of PMS had access to the vacuoles. A series of other electron carriers, including phenyl methanes, phenazines, oxazines, a xanthene, and a naphthoquinone, given continuously for 18 h, also induced the disappearance of the Leishmania. The most potent was crystal violet, active at 70 nM. The presence of apolar substituents enhanced activity and this is probably related to increased permeation of the dyes. Finally, PMS, as well as other electron carriers examined, also reduced the growth of Leishmania promastigotes in culture. The results are compatible with a direct effect of the drugs on the intracellular amastigotes, involving only a permissive participation of the macrophages. We propose that the diverse agents destroy the amastigotes by redox-cycling generation of active oxygen metabolites at or near the parasites. Alternatively, the effect of the drugs could be mediated by toxic free radical reduction species of the drugs or by interference with electron flow or with the intermediary metabolism of Leishmania.

Progressive-addition lenses in the management of esotropia with a high accommodation/convergence ratio

In 25 children esotropia due to abnormal synkinesis between accommodation and accommodative convergence was corrected with progressive-addition lenses. Twelve of the children had been wearing conventional bifocals; the other 13 were given progressive lenses for the first time. The near esodeviation was satisfactorily neutralized in most cases, and nearly all the children had some stereopsis. All adapted well and without difficulty to the progressive lenses.