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Purpose To test the hypothesis that severely damaged eyes are more likely to experience postoperative complications after an ArtificialIris®(AI) implantation than other iris defects.Methods Patients after iris reconstruction with an AI were included in this consecutive case series of the Department of Ophthalmology, University of Mainz, Germany. Best-corrected visual acuity (BCVA), objective refraction (KR 8900 Topcon, Tokyo, Japan) and Scheimpflug imaging of the anterior segment with Pentacam®(Oculus, Wetzlar, Germany)and postoperative complications were evaluated.Results Thirty-two eyes of 32 patients after AI implantation were included, separated in partial or total aniridia in a closed globe (group 1, n = 16) and after perforating globe injury (group 2, n = 16). Two or more previous surgeries in the corresponding eye were found in two patients (12.5%) in group 1 and eleven patients (69%) in group 2 (p = 0.001). The time span between initial trauma or iris defect and AI implantation was not significantly related to the occurrence and severity of postoperative complications (p= 0.89). Postoperative complications were classified into mild and severe and showed no differences between group 1 and group 2 (mild: 1 vs. 0; p= 0.52; severe: 5 vs. 6 p= 0.8).Conclusion AI implantation is a treatment option for various iris defects. An individual, case-based decision should be made with strict indication also considering other possible methods for pupil reconstruction. The postoperative outcome is not affected by the time point of AI implantation. So, an implantation is already possible as early as six weeks after the previous trauma.

High resolution differential scanning calorimetry (DSC) and molecular dynamics (MD) simulations were used to investigate the effect of three lignin dimers on the gel to fluid phase transition in DPPC lipid bilayers. The goal of this research is to begin to understand the partitioning of model lignin dimers into lipid bilayers and its effects on the gel to fluid transition temperature (Tm). The long-term objective is to establish structure–function relationships for well-defined lignin derivatives at biologically relevant surfaces. This work uses a newly synthesized guiacylglycerol guaiacol ester with a hydroxypropenyl (HOC3H4−) group resembling natural lignin (GG dimer), compared with a truncated GG dimer without the HOC3H4– and benzyl-modified GG dimers. The DSC results show that the dimer most like natural lignin (with a hydroxypropenyl tail) has log K= 2.72 ± 0.05, and MD simulations show that it associates with the headgroups of the lipid but does not penetrate strongly into the interior of the bilayer. Therefore, this dimer has little effect on the Tmvalue. In contrast, the truncated dimer, which has been used as a representative GG dimer in prior studies, partitions into the bilayer, as seen in MD simulations, and shifts Tmbecause of its increased lipophilicity (DSC log K= 3.45 ± 0.20). Similarly, modification of the natural GG dimer by benzylation of the phenol makes it lipophilic (DSC log K= 3.38 ± 0.28), causing it to partition into the bilayer, as seen in MD simulations and shift Tm. In MD, we capture the transition from gel to fluid phase by defining and analyzing a normalized deuterium order parameter averaged over all carbon atoms located in the middle of the lipid tails. In this way, the phase transition can be clearly observed and, importantly, MD results show the same trend of transition temperature shifts as the DSC results. Furthermore, we compare partition coefficients estimated from free energy profiles calculated in MD to those obtained from experiment and they are in qualitative agreement. The success at predicting the structural effects of lignin dimers on lipid bilayers suggests that MD simulations can be used in the future to screen the interactions of lignin oligomers and their derivatives with lipid bilayers.

The need for renewable bioenergy sources has renewed interest in lignin chemistry; however, structural elucidation and characterization of lignin degradation products remain a challenge because of lack of effective analytical methods. The analysis of lignin oligomers has been accomplished by simple deprotonation of weakly acidic phenolic moieties using NaOH and analyzed in a negative ESI mass spectrometry. Although simple deprotonation works to produce excellent results for many types of lignin compounds, others can undergo extensive in-source fragmentation for certain bond types making structural elucidation more complicated. Herein, we present an alternative method for analyzing lignin model compounds using chloride adduct chemistry. In this study, nine β-O-4 dimers, an (4-Ο-α)(β-Ο-4) trimer, and a (β-O-4)(β-O-4) trimer were synthesized and analyzed using chloride adduct mass spectrometry in the negative mode using NH4Cl as the chloride source. Stable chloride adducted molecular ions were observed for all analyzed compounds. Tandem mass spectrometry experiments performed on each precursor ion produced “signature” fragment ions specific to each analyte. The compelling features of this method include the production of stable chloride adduct molecular ions that do not undergo in-source fragmentation, in contrast to simple deprotonation methods that can lead to extensive fragmentation for some structures, the appearance of the chlorine isotope pattern for enhanced recognition of molecular ions, and production of monolignol sequence specific fragment ions using tandem mass spectrometry.

Objective: The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic resonance spectroscopy sequence (point-resolved spectroscopy) parameter optimization that enables thermometry during deep hyperthermia treatments.Materials and Methods: Different Lorentz peak-fitting methods and a peak finding method using singular value decomposition of a Hankel matrix were compared. Phantom measurements on organic substances (mayonnaise and pork) were performed inside the hyperthermia 1.5-T magnetic resonance imaging system for the parameter optimization study. Parameter settings such as voxel size, echo time, and flip angle were varied and investigated.Results: Usually all peak analyzing methods were applicable. Lorentz peak-fitting method in MATLAB proved to be the most stable regardless of the number of fitted peaks, yet the slowest method. The examinations yielded an optimal parameter combination of 8 cm3voxel volume, 55 millisecond echo time, and a 90° excitation pulse flip angle.Conclusion: The Lorentz peak-fitting method in MATLAB was the most reliable peak analyzing method. Measurements in homogeneous and heterogeneous phantoms resulted in optimized parameters for the magnetic resonance spectroscopy sequence for thermometry.

The integrated use of optical technologies for patient monitoring is addressed in the framework of time-resolved treatment delivery for scanned ion beam therapy. A software application has been designed to provide the therapy control system (TCS) with a continuous geometrical feedback by processing the external surrogates tridimensional data, detected in real-time via optical tracking. Conventional procedures for phase-based respiratory phase detection were implemented, as well as the interface to patient specific correlation models, in order to estimate internal tumor motion from surface markers. In this paper, particular attention is dedicated to the quantification of time delays resulting from system integration and its compensation by means of polynomial interpolation in the time domain. Dedicated tests to assess the separate delay contributions due to optical signal processing, digital data transfer to the TCS and passive beam energy modulation actuation have been performed. We report the system technological commissioning activities reporting dose distribution errors in a phantom study, where the treatment of a lung lesion was simulated, with both lateral and range beam position compensation. The zero-delay systems integration with a specific active scanning delivery machine was achieved by tuning the amount of time prediction applied to lateral (14.61 ± 0.98 ms) and depth (34.1 ± 6.29 ms) beam position correction signals, featuring sub-millimeter accuracy in forward estimation. Direct optical target observation and motion phase (MPh) based tumor motion discretization strategies were tested, resulting in -0.3(2.3)% and -1.2(9.3)% median (IQR) percentual relative dose difference with respect to static irradiation, respectively. Results confirm the technical feasibility of the implemented strategy towards 4D treatment delivery, with negligible percentual dose deviations with respect to static irradiation.

Real-time experiments involving fragmentation of the precursor molecular ion of n-butylbenzene (m/z134) to produce product ions C7H+7(m/z91) and C7H+8(m/z92), were used to observe the motion of ions in a commercial quadrupole ion trap. Initially, ghost resonance peaks were observed for excitation of the precursor ion at qzvalues of 0.4 and 0.5 on the qzaxis of the stability diagram. Further experiments involving the generation of two-dimensional contour plots confirmed that these ghost peaks, which were in agreement with mathematical equations describing the motion of ions in a quadrupole field, arose due to waveboard artifacts. Two-dimensional contour surface plots showed non-linear secular frequency canyons from a qzvalue of 0.5 to higher values corresponding with higher drive radio frequency (rf) voltages on the stability diagram. This observation confirmed that ions are subjected to non-linear effects in this mass scan range. The octapole and hexapole field lines were observed at qzvalues of 0.65 and 0.78, respectively.

Abstract Increasing evidence supports a role for altered mitochondrial function in the pathogenesis of neuron degeneration in Alzheimer’s disease (AD). Although several studies have examined the effect of amyloid beta peptide (Aß), on activities of individual proteins in primary neuron cultures, there have been no studies of the effects of Aß on the mitochondrial proteome. Here, we quantitatively measured changes in mitochondrial proteins of primary rat cortical neuron cultures exposed to 25 µM Aß 25–35 for 16 h using isotope coded affinity tag (ICAT) labeling and 2-dimensional liquid chromatography/tandem mass spectrometry (2D-LC/MS/MS) which allows simultaneous identification and quantification of cysteine-containing proteins. The analysis of enriched mitochondrial fractions identified 10 proteins including sodium/potassium-transporting ATPase, cofilin, dihydropyrimidinase, pyruvate kinase and voltage dependent anion channel 1 that were statistically significantly ( P < 0.05) altered in Aß-treated cultures. Elevations of proteins associated with energy production suggest that cells undergoing Aß-mediated apoptosis increase synthesis of proteins essential for ATP production and efflux in an attempt to maintain metabolic function.

Bovine embryos produced in vitro differ considerably in quality from embryos developed in vivo. The in vitro production system profoundly affects the competence to form blastocysts, the number of cells of the total embryo and of the inner cell mass (ICM), and the incidence of apoptosis. To our knowledge, the effects of different postfertilization regimens before and after completion of the fourth embryonic cell cycle on these aspects have not yet been investigated. In the present study, we assessed the blastulation rate by stereomicroscopy and the cell number of the total embryo, of the ICM, and of the cells with apoptotic changes by confocal laser-scanning microscopy after staining with propidium iodide and TUNEL. Two groups of embryos were developed in heifers, after superovulation, until 45 or 100 h postovulation (po) and, after collection on slaughter, were further cultured in vitro until Day 7 po. A third and fourth group comprised embryos that were produced entirely in vitro or in vivo. The results indicate that passage in vivo of the fourth cell cycle does not prevent acceleration of the formation of the blastocoele in vitro but may be the critical factor contributing to a higher cell number in the total blastocyst and its ICM. The lower quality of in vitro-produced embryos can be attributed to the ICM having less viable cells because of a lower number of cells and a higher incidence of apoptosis that appears to be determined before completion of the fourth cell cycle.

Objective:Several studies have reported an association between abdominal aortic dilatation and peripheral arterial occlusive disease. Narrowing of aortic diameter, also called abdominal aortic hypoplasia, and peripheral arterial occlusive disease have received insufficient attention. Precise estimates of the relationship between aortic hypoplasia and peripheral arterial occlusive disease are lacking. In this study, we assessed the relationship between abdominal aortic diameter and peripheral arterial occlusive disease. Methods:In this cross-sectional study, we analyzed 1572 patients 18 to 79 years of age, newly referred to the vascular center of our hospital with clinically manifest atherosclerotic arterial disease or for treatment of cardiovascular risk factors. Diameter measurements were used to subdivide patients according to tertiles of abdominal aortic diameter. Peripheral arterial occlusive disease was assessed by adjusted Rose questionnaire, ankle-brachial pressure index, and the presence of gangrene or leg ulcers. Results:Compared with patients with normal aortic diameter, peripheral arterial occlusive disease was twice as prevalent in patients at both ends of the aortic diameter spectrum. When the lowest tertile was compared with the middle tertile in male patients, the adjusted odds ratio was 1.7 (95% CI, 1.0-3.1). When the highest tertile was compared with the middle tertile, the adjusted odds ratio was 2.1 (95% CI, 1.2-3.4). Similar results were found in female patients. The adjusted odds ratio of lowest versus middle tertile was 2.4 (95% CI, 1.1-5.0) and 1.8 (95% CI, 0.8-4.0) when the highest tertile was compared with the middle tertile. Conclusion:The risk of peripheral arterial occlusive disease was increased in the lower and upper distribution of aortic diameter. Apparently, both patients with an aortic diameter too large and patients with an aortic diameter too small are prone to peripheral arterial occlusive disease. This is the first large study that shows that small aortic diameter is associated with peripheral arterial occlusive disease. (J Vasc Surg 2001;34:1085-9.)

Purpose:Several antithrombotic therapies are available for the treatment of patients with peripheral vascular diseases. It is unknown how quality of life and costs of treatment are influenced by different therapies. This study assessed the cost-effectiveness of oral anticoagulants versus aspirin in patients after infrainguinal bypass grafting surgery. Methods:Clinical outcome events and event-free survival were collected from 2650 patients in 77 centers who participated in the Dutch Bypass Oral anticoagulants or Aspirin trial. Approximately half the patients had critical ischemia; 60% received vein grafts, and 20% had femorocrural bypass grafts. A model that was primarily driven by clinical outcome events was used as a means of determining quality of life (EuroQol EQ-5D) and costs for each patient. The main outcome measure was the incremental health care costs in relation to the additional number of quality-adjusted life years and the additional number of event-free years. Results:The mean costs during the 21 months of follow-up were ϵ 6875 per patient in the oral anticoagulants group versus ϵ 7072 in the aspirin group (difference, 197; 95% CI, –746 to 343). The event-free survival was 1.10 years in the group treated with oral anticoagulants versus 1.09 years in the group treated with aspirin (difference, 0.01; 95% CI, –0.07 to 0.08), whereas the corresponding quality-adjusted life years were 1.06 and 1.05, respectively (difference, 0.01; 95% CI, –0.03 to 0.06). Conclusion:Health care costs, event-free survival, and quality-adjusted life years in patients after infrainguinal bypass surgery were not different in patients treated with aspirin and patients treated with oral anticoagulants. The extra costs of monitoring patients treated with oral anticoagulants were limited and play no role in the decision for treatment. (J Vasc Surg 2001;34:254-62.)

In the normal operation of quadrupole ion trap mass spectrometers, approximately half of the trapped ions are ejected through the source endcap during a mass‐selective instability scan. This reduces the sensitivity of the instrument by ∼50%. In this preliminary study, a circuit was constructed that produced a dipolar DC offset on the axial modulation waveform to recover this lost ion current. A variable (0 to 10 V DC), positive and negative offset was applied to the source and detector endcap, respectively. This DC offset axially displaced the ion cloud toward the detector endcap increasing the probability of detection. Several compounds, including 11 pesticides, were evaluated. Sensitivity enhancements ranged from 13 to 97% (theoretical 100%). No spectral resolution problems were observed; however, a compound‐dependent mass discrimination was observed in several cases. This mass discrimination problem is currently under investigation. Copyright © 2001 John Wiley & Sons, Ltd.

An apparatus has been constructed wherein the transparency of a glass/polymer sheet/glass assembly undergoing vacuum de-airing can be monitored continuously. Experimental conditions can be varied independently, such as vacuum level, cold (ambient) de-airing time, and oven temperature. The behavior of polyvinyl butyral and an ionomeric interlayer (SGP) with different rheological properties and surface roughness were studied using various de-airing conditions. Initial results show that the clarity of the assembly is a monotonically increasing function of time in the oven at a given vacuum level. All assemblies made from these interlayers became clear with sufficient vacuum time at ambient temperature. The assembly from polyvinyl butyral with protrusion-type surface pattern clears up faster than that with indentation-type. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 521–528, 2001

Structures consisting of thin plates stiffened by a system of ribs or diaphragms form a class of structural elements of practical importance in various engineering applications. A differential quadrature analysis of free vibration of plates with eccentric stiffeners is presented. The plate and the stiffeners are treated separately. Simultaneous governing differential equations are derived from the plate dynamic equilibrium, the stiffener dynamic equilibrium, and equilibrium and compatibility conditions along the interface of a plate segment and a stiffener. The plate and the stiffeners have displacements in three dimensions. Shear forces and in-plane forces in the plate are considered to satisfy the compatibility at the interface of a plate segment and a stiffener. Meanwhile, in-plane inertia effects in the plate and in the stiffener are ignored. The application of the differential quadrature method is demonstrated by three examples: a simply supported plate with central eccentric stiffener, a clamped square plate with central eccentric stiffener, and a double-ribbed plate with all edges clamped. The natural frequencies are compared with the experimental results, and with the results obtained by finite element analysis. Very good agreement was found.

Objectives:The purpose of this study was to determine the optimal intensity of oral anticoagulation in patients who participated in a randomized trial of oral anticoagulants or aspirin after infrainguinal bypass graft surgery. Methods:The distribution of patient-time spent in international normalized ratio (INR) classes of 0.5 INR unit was calculated assuming a linear change between successive measurements. INR-specific incidence rates of ischemic and hemorrhagic events were calculated as the ratio of the number of events at a certain INR category and the total patient-time spent in that class. The relationship between INR class and event rates was quantified by rate ratios calculated in a Poisson regression model. Results:In 1326 patients (mean age, 69 years) 41,928 INR measurements were recorded in 1698 patient-years. Patients spent 50% of the total time within the target range of 3.0 to 4.5 INR. Most of the patient-time (60%) was spent between 2.5 and 3.5 INR. For each increasing class of 0.5 INR, the incidence of ischemic events (n = 154, INR data on event available in 49%) decreased by a factor of 0.97 (95% CI, 0.87-1.08). The incidence of major bleeding (n = 123, INR data on event available in 65%) increased significantly by a factor of 1.27 (95% CI, 1.19-1.34) for each increasing 0.5 INR category. The optimal target range was 3.0 to 4.0 INR, with an incidence of 3.8 events (0.9 ischemic and 2.9 hemorrhagic) per 100 patient-years. Conclusions:The target range of 3.0 to 4.0 INR is the optimal range of achieved anticoagulation intensity and is safe for the prevention of ischemic events in patients after infrainguinal bypass graft surgery. (J Vasc Surg 2001;33:522-7.)

Objective:To provide a long-term perspective on the durability of the proximal abdominal aortic aneurysm endograft fixation from a single device series with perpendicular neck measurements in two groups of patients with complete 2- and 3-year follow-up. Design:This was a prospective study of postoperative, radiologic images. Setting:The study used a referral center, institutional practice, and ambulatory patients. Subjects:From January 1994 until May 1998, 37 endografts were implanted for abdominal aortic aneurysm. In the first postoperative year, there were four unrelated deaths and six conversions, leaving 27 patients with complete 24-month data and 13 with complete 36-month data. Main Outcome Measure:Computed tomography angiograms were processed on a work station to measure the neck perpendicular to the central lumen line of the aorta. The surface area at the proximal endovascular anastomosis was recorded at each follow-up interval and related to the postoperative size at the same level. Results:Significant dilatation of the surface area was found: 20% (16% to 27%) at 24 months (c2= 30; P< .001, Friedman) and 23% (18% to 28%) at 36 months (c2= 27; P< .001, Friedman). This increase in neck size was continuous and linear, with a yearly rate of approximately 10% surface area; translated into diameter, this approximates 1 mm/y. Conclusion:A continuous aortic enlargement of approximately 1 mm/y at the level of the proximal endovascular anastomosis was found. Because of the practice of oversizing the endograft relative to the infrarenal aortic neck, a loss of the endovascular seal may not become apparent until several years after endovascular abdominal aortic aneurysm repair is performed. (J Vasc Surg 2001;33:S64-9.)

Lignin derived from lignocellulosic biomass is the largest source of renewable bioaromatics present on earth and requires environmentally sustainable separation strategies to selectively obtain high-value degradation products. Applications of supramolecular interactions have the potential to isolate lignin compounds from biomass degradation fractions by the formation of variable inclusion complexes with cyclodextrins (CDs). CDs are commonly used as selective adsorbents for many applications and can capture guest molecules in their internal hydrophobic cavity. The strength of supramolecular interactions between CDs and lignin model compounds that represent potential lignocellulosic biomass degradation products can be characterized by assessing the thermodynamics of binding stability. Consequently, the inclusion interactions of β-CD and lignin model compounds G-(β-O-4′)-G, G-(β-O-4′)-truncG (guaiacylglycerol-β-guaiacyl ether), and G-(β–β′)-G (pinoresinol) were investigated empirically by electrospray ionization mass spectrometry and isothermal titration calorimetry, complemented by molecular dynamics (MD) simulations. Empirical results indicate that there are substantial differences in binding stability dependent on the linkage type. The lignin model β–β′ dimer showed more potential bound states including 1:1, 2:1, and 1:2 (guest:host) complexation and, based on binding stability determinations, was consistently the most energetically favorable guest. Empirical results are supported by MD simulations that reveal that the capture of G-(β–β′)-G by β-CD is promising with a 66% probability of being bound for G-(β-O-4′)-truncG compared to 88% for G-(β–β′)-G (unbiased distance trajectory and explicit counting of bound states). These outcomes indicate CDs as a promising material to assist in separations of lignin oligomers from heterogeneous mixtures for the development of environmentally sustainable isolations of lignin compounds from biomass fractions.

Purpose:The incidence, time-of-onset, and anatomical distribution of recurrent stenoses after remote endarterectomy in superficial femoral artery (SFA) occlusive disease were studied. Methods:Patients undergoing SFA remote endarterectomy procedures were examined with duplex surveillance. Patients were examined at 6 weeks, 3, 6, 9, and 12 months, and then annually. Recurrent stenosis was defined as a peak systolic velocity ratio of 2.5 or higher. Duplex results were also compared with clinical and hemodynamic changes. Results:Restenoses were identified in 46 of 101 (46%) limbs treated after a mean interval of 5.8 months (range, 1 to 18 months). These 46 limbs formed the base of this study. The median follow-up period was 25 months. Thirty-eight (83%) of all restenoses were detected within 1 year. The lesions were located within the entire SFA and were not specifically related to the adductor canal or distal stented region only. Multiple stenoses were found in 21 limbs. Only 10 (22%) restenoses were correlated with worsening of clinical symptoms, change of ankle-brachial index, or both. Ten of 23 cases (43%) of nonrevised restenoses progressed to occlusion. These 10 occlusions occurred in all patients with restenosis that developed within the first year. Nonrevised late restenoses (more than 1 year) were not associated with any reocclusion. Conclusion:Recurrent stenoses after SFA remote endarterectomy were noticed in 46 of 101 (46%) limbs. Most restenoses (83%) developed within the first year. In the nonrevised group, time-of-onset restenosis (less than 1 year) was correlated with a higher risk for occlusion ( P= .02). The location of restenoses were found without any anatomical site of preference along the entire endarterectomized SFA segment. (J Vasc Surg 1999;30:106-13.)

Purpose:The purpose of this study was to compare quality of life in patients with and without various ischemic complications after infrainguinal bypass grafting surgery for occlusive vascular disease. Methods:A sample of patients (n = 746) randomized in the Dutch BOA study (n = 2645), a multicenter trial that compared the effectiveness of oral anticoagulant therapy with aspirin in the prevention of infrainguinal bypass graft occlusions, was entered in this study. On the basis of clinical outcomes of the trial, the patients were grouped as follows: patients with patent grafts (n = 409); patients with nontreated graft occlusions, subdivided into an asymptomatic group (n = 32) and a symptomatic group (n = 65); patients with subsequent revascularizations (n = 194); patients with amputations (n = 36); and patients with failed secondary revascularizations followed by secondary amputation (n = 38). In case an outcome event occurred, the patients were regrouped accordingly. Every half year, the patients completed a Short Form–36 and a EuroQol questionnaire. A multilevel model was used for repeated measure analysis. Results:The mean follow-up time was 21 months. The quality of life in patients with nontreated asymptomatic occlusions was roughly similar to the quality of life in patients with patent grafts. Patients with symptomatic nontreated occlusions had the lowest outcome with regard to pain as compared with the other groups. Furthermore, physical and social functioning was lower for these patients than for patients with patent grafts. Revascularizations, successful or not, negatively affected pain, social functioning, and physical and emotional role. After successful revascularization, some improvement was observed in pain, physical and social functioning, and general and mental health as compared with the group with nontreated symptomatic occlusions. Amputation deteriorated physical functioning strikingly, especially after failed secondary revascularization. These patients also had the lowest scores of all the groups in the dimensions of social functioning, physical and emotional role, and mental health. EuroQol score showed deterioration of quality of life after all events, except for asymptomatic occlusions. The same patterns emerged if we stratified our analysis according to the indication for the initial operation: claudication or limb salvage. Quality of life was constant over time in all the groups in the observed period. Conclusion:Quality of life in patients with asymptomatic occluded grafts is similar to quality of life in patients with patent grafts. Revascularization of symptomatic occluded grafts improves quality of life to a certain extent. Amputation, in particular after failed secondary revascularization, seemed to be the lowest possible outcome. The results of the Short Form-36 and EuroQol measurements were in line with the clinical expectations. The association of disease severity with scores on the instruments supports the construct validity of these outcome measures for an objective assessment of quality of life in controlled studies. (J Vasc Surg 1999;29:913-9.)

The development of postural adjustments during reaching movements was longitudinally studied in seven infants with cerebral palsy (CP) between 4 and 18 months of age. Five infants developed spastic hemiplegia, one spastic tetraplegia, and one spastic tetraplegia with athetosis. Each assessment consisted of a simultaneous recording of video data and surface EMGs of arm, neck, trunk, and leg muscles during reaching in various lying and sitting positions. The basic organization of postural adjustments of the children developing spastic CP was intact. Their main problem was a deficient capacity to modulate the postural adjustments to task‐specific constraints ‐ a deficit which was attributed to a combination of an impaired motor coordination and deficits in sensory integration. The child with spastic‐dyskinetic CP showed distinct abnormalities in the basic organization of postural adjustments.

The development of postural adjustments during reaching movements was longitudinally studied in seven infants with cerebral palsy (CP) between 4 and 18 months of age. Five infants developed spastic hemiplegia, one spastic tetraplegia, and one spastic tetraplegia with athetosis. Each assessment consisted of a simultaneous recording of video data and surface EMGs of arm, neck, trunk, and leg muscles during reaching in various lying and sitting positions. The basic organization of postural adjustments of the children developing spastic CP was intact. Their main problem was a deficient capacity to modulate the postural adjustments to task-specific constraints – a deficit which was attributed to a combination of an impaired motor coordination and deficits in sensory integration. The child with spastic-dyskinetic CP showed distinct abnormalities in the basic organization of postural adjustments.

A thermosolid mechanics analysis based on sound thermodynamic and mechanical principles is derived for a thermoelastic solid in which the elastic coefficient is temperature-dependent, and thus the TEC (thermal expansion coefficient) must be stress-dependent. The theory is applied to the case of slender elastic members with full axial restraint and subjected to a uniform increase in temperature. Numerical results are presented for a wide range of materials and slenderness ratios.

This paper provides a numerical tool to calculate the load provided by the clamp plate which anchors the disk stack of a Winchester disk drive and the distribution of that load circumferentially around the plate support. The analysis is verified by comparison with experimental data.

We attempted to assess whether magnetic resonance imaging (MRI)-MR angiography (MRA)-MR spectroscopy (MRS) measurements can be used in the differentiation of patients in whom severe carotid lesions result in chronically hypoperfused regions and in whom the collateral capacity is sufficient to maintain a normal cerebral blood flow. Sixty-six patients with severe stenosis of the internal carotid artery (ICA) and 19 control subjects underwent MRI, ¹H MRS, and MRA. Anaerobic metabolic changes in the middle cerebral artery (MCA) territory were studied by assessing N-acetyl-L-aspartate (NAA)/choline and lactate/NAA ratios. Quantitative flow was measured in the ICA, in the basilar artery, and in the MCA. Thirty-four patients had borderzone infarcts, 16 patients had territory infarcts, and 16 patients had no infarcts on MRI. Patients with borderzone infarcts had significantly reduced flow in the ICA (P &lt; 0.001) and in the MCA (P &lt; 0.05) and decreased NAA/choline ratios (P &lt; 0.001) in non-infarcted regions compared with control subjects (P &lt; 0.001) but also compared with patients with territory infarcts (P &lt; 0.05) and patients without infarcts (P &lt; 0.05). Flow measurements in the ICA and MCA and metabolic measurements in the MCA territory can be applied to select patients in whom cerebral perfusion pressure is insufficient to maintain normal cellular integrity. J. Magn. Reson. Imaging 1999;9:1–9 © 1999 Wiley-Liss, Inc.