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Background:The center-center technique for syndesmosis fixation has been described as an improved and reliable technique for proper reduction of the syndesmosis during ankle fracture repair. Concurrently, the use of flexible fixation with a suture button is becoming an established means of syndesmosis stabilization. The purpose of this cadaveric study was to assess for medial structure injury during the placement of a suture button using the center-center technique for ankle syndesmosis repair at 3 insertion intervals.Methods:Simulated open syndesmosis repair was performed on 10 cadaveric specimens. Three intervals were measured at 10 mm, 20 mm, and 30 mm proximal to the level of the distal tibial articular surface along the fibula. Proper longitudinal alignment of the center-center technique was completed under fluoroscopic guidance and was marked on the medial aspect of the tibia. The 3 intervals were drilled in the appropriate technique trajectory. The suture button was subsequently passed through each drill-hole interval. A single observer used a digital caliper to measure the distance from each suture button aperture with respect to the tibialis anterior tendon, tibialis posterior tendon, and greater saphenous vein and nerve.Results:A total of 30 interval measurements (10 cadavers with 3 suture button segments each) were used for data analysis. Direct impingement on the greater saphenous vein was seen in 11 of 30 (36.6%) interval measurements. Six of the 11 (54.5%) observed saphenous structure impingement events occurred at the 10-mm drill hole.Conclusion:The results of the present study suggest that the use of the center-center technique for syndesmosis repair with suture button fixation risks preventable injury to the greater saphenous neurovasculature.Clinical Relevance:To understand the medial ankle anatomy, as it pertains to insertion of flexible syndesmotic fixation in a cadaveric model, to aid in prevention of clinical iatrogenic injury.

This case study describes the failure analysis of an automotive lower ball joint that fractured under normal driving conditions. Through spectroscopy, the material was determined to be SAE-AISI 5135H steel. The metallographic examination revealed a tempered martensitic structure, and hardness measurements radially across the surface of the cut ball stud suggested that the stud was through hardened. Scanning electron microscopy of the fracture surfaces indicated fatigue as the main failure mechanism. Finite element analysis was used to analyze the performance of the part under a normal loading condition. A detailed fatigue analysis to determine the effect of various loads on the life of the ball joint was completed using three methods: S-N curve approximation using hardness values, S-N approach using Basquin’s equation, and a linear elastic crack-growth model. The cause of failure was determined to be from surface cracks forming in the high stress concentration neck region where the ball and stud are joined. The presence of a small surface flaw in this region was shown to significantly reduce the fatigue life of the ball joint.

Drawing on a thematic analysis of relevant policy documents, the aim of this paper is to comment on an apparent disconnect between two associated contemporary UK policy areas: planning for heatwaves and community resilience. Regional and national policy documents that plan for heatwaves in the UK tend to focus on institutional emergency responses and infrastructure development. In these documents, although communities are mentioned, they are understood as passive recipients of resilience that is provided by active institutions. Meanwhile, contemporary discussion about community resilience highlights the potential for involving communities in planning for and responding to emergencies (although the concept is also the subject of critique). Within this context, the paper proposes that – through engagement with the ‘community resilience’ policy agenda and its critique – effort should be made to articulate and realise greater participation by individuals, and voluntary and community sector groups in heatwave preparation, planning and response.

Summary Background Proximal medial gastrocnemius release (PMGR) is the newest technique for addressing clinically significant gastrocnemius contracture, whose safety and efficacy has been evaluated in several modern case series. Material & Methods This anatomic study evaluated the safety of a PMGR technique modification by testing the hypothesis that the lateral border of the semimembranosus would be easily identified under surgical conditions and would localize the approach safely away from popliteal structures. Results & Conclusions The results of this study revealed that although the semimembranosus was easily referenced, it localized the approach with a much narrower margin for safety than suggested by previous literature.

Peroneal tendon disorders are a common cause of persistent posterolateral ankle pain. The diagnosis of peroneal tendon pathology is frequently overlooked by the referring clinician, who is often unfamiliar with this pathology. In this chapter, we discuss our nonoperative protocol as well as our surgical management of peroneal tendon repair, tenolysis, tenodesis, SPR repair/fibular groove deepening for tendon instability, excision of an os peroneum, and tendon reconstruction with autograft/allograft transfers. Also discussed is our postoperative protocol as well as pearls/pitfalls during surgery

Background: Ankle fractures are among the most common lower extremity injuries. Proper care requires evaluation for syndesmotic ligament disruption. Ankle arthroscopy has been proposed as an intraoperative tool that can evaluate stability. Our focus was to evaluate the amount of displacement produced in the coronal, sagittal, and transverse planes visualized through ankle arthroscopy in a cadaveric model. Methods: Seven below-knee specimens were mounted in a traction tower. Four groups were evaluated: no ligamentous disruption; anterior inferior tibiofibular ligament and interosseous ligament disruption; above plus anterior talofibular ligament and calcaneofibular ligament disruption; and posterior inferior tibiofibular ligament and transverse ligament disruption. Force was applied and measured using a digital scale. The amount of displacement of the fibula in relation to the center of the incisura was measured under arthroscopic evaluation using a calibrated probe. Results: An intact syndesmosis and lateral ankle ligaments provided multiplanar stability. In group 2, syndesmosis diastasis was appreciated in the transverse-external rotation plane with as little as 6 lb of force. In group 3, a greater amount of displacement was appreciated with less force. Multiplane instability was visible in every specimen with as little as 2 lb of force. Group 4 specimens were completely disrupted and so grossly unstable that testing was impossible. Conclusion: Ankle arthroscopy has the potential to evaluate even partial disruption of the syndesmotic ligament complex. Instability in the sagittal and transverse planes was encountered early in the spectrum of disruption. Traditional evaluation methods have poor sensitivity for instability in these planes. Clinical Relevance: Arthroscopic evaluation of subtle displacement in multiple planes may assist the surgeon in understanding the extent of the syndesmotic injury. Further studies are necessary to determine to what extent instability requires fixation as well as the role for arthroscopy in assessing anatomic reduction of the syndesmosis after fixation is performed.

Objective To evaluate the acceptability and feasibility of a scalable obesity treatment program integrated with pediatric primary care (PC) and delivered using interactive voice technology (IVR) to families from underserved populations. Design and Methods Fifty parent-child dyads (child 9-12 yrs, BMI > 95th percentile) were recruited from a pediatric PC clinic and randomized to either an IVR or a wait-list control (WLC) group. The majority were lower-income, African-American (72%) families. Dyads received IVR calls for 12 weeks. Call content was informed by two evidence-based interventions. Anthropometric and behavioral variables were assessed at baseline and 3-month follow-up. Results Forty-three dyads completed the study. IVR parents ate one cup more fruit than WLC (P 75% agreed that the calls were useful, made for people like them, credible, and helped them eat healthy foods. Conclusion An obesity treatment program delivered via IVR may be an acceptable and feasible resource for families from underserved populations.

Background: The “tibiofibular line” is a new axial computed tomography parameter for assessing syndesmosis reduction, which references the flat anterolateral surface of the fibula and anterolateral tibial tubercle. These same bony landmarks are easily visualized via a lateral approach to the fibula. This cadaveric study assessed the practical aspects of measuring the tibiofibular line intraoperatively. Methods: Three observers simulated the tibiofibular line using operative rulers in 3 measurement series utilizing 10 cadaveric specimens: intact syndesmosis, syndesmosis reduction, and fixation after application of lateral plate and screws to the fibula, and post syndesmosis reduction and fixation without plate and screws. Results: The majority (78%) of clinical tibiofibular line measurements were within the “normal” range (0-2 mm). However, there was a general trend toward malreduction (>2 mm) across measurement series. Intraobserver variability ranged from poor to excellent (intraclass correlation range, 0.12-0.85, Fleiss kappa range, 0.19-0.40) and interobserver reliability was only generally in the fair range (intraclass correlation range, 0.49-0.61; Fleiss kappa range, 0.19-0.40). Conclusion: Taken as a whole, these findings found that the technique was feasible but clearly indicated that further refinement of this protocol, including the use of computed tomography, would be needed to determine if better control of confounding variables would reveal better observer reliability. Clinical Relevance: The CT-based TFL technique for syndesmosis reduction assessment could not reliably be translated into an intraoperative open technique because of the confounding effects of subjectivity and operator error.

Background: Electromagnetic bone growth stimulators have been found to biologically enhance the bone healing environment, with upregulation of numerous growth factors. The purpose of the study was to quantify the effect, in vivo, of pulsed electromagnetic fields (PEMFs) on growth factor expression and healing time in fifth metatarsal nonunions. Methods: This was a prospective, randomized, double-blind trial of patients, cared for by 2 fellowship-trained orthopedic foot and ankle surgeons. Inclusion criteria consisted of patients between 18 and 75 years old who had been diagnosed with a fifth metatarsal delayed or nonunion, with no progressive signs of healing for a minimum of 3 months. Eight patients met inclusion criteria and were randomized to receive either an active stimulation or placebo PEMF device. Each patient then underwent an open biopsy of the fracture site and was fitted with the appropriate PEMF device. The biopsy was analyzed for messenger-ribonucleic acid (mRNA) levels using quantitative competitive reverse transcription polymerase chain reaction (QT-RT-PCR). Three weeks later, the patient underwent repeat biopsy and open reduction and internal fixation of the nonunion site. The patients were followed at 2- to 4-week intervals with serial radiographs and were graded by the number of cortices of healing. Results: All fractures healed, with an average time to complete radiographic union of 14.7 weeks and 8.9 weeks for the inactive and active PEMF groups, respectively. A significant increase in placental growth factor (PIGF) level was found after active PEMF treatment ( P = .043). Other factors trended higher following active PEMF including brain-derived neurotrophic factor (BDNF), bone morphogenetic protein (BMP) -7, and BMP-5. Conclusion: The adjunctive use of PEMF for fifth metatarsal fracture nonunions produced a significant increase in local placental growth factor. PEMF also produced trends toward higher levels of multiple other factors and faster average time to radiographic union compared to unstimulated controls. Level of Evidence: Level I, prospective randomized trial.

Milk-processing plants generate significant quantities of wastewater with relatively high organic matter concentrations on a daily basis. In addition to environmental damage that can result from the discharge of these wastewaters into the natural waterways, the presence of products such as milk solids into wastewater streams represents a loss of valuable product for the plants. This paper presents a review of wastewater management practices employed by six milk-processing plants in Victoria, Australia. In all six plants investigated, milk powder represents a major product. During the milk powder production, water is evaporated, condensed and can be reused for various purposes with a significant impact on water usage. Other major products are anhydrous milk fat, cheese, butter, and UHT milk. The effectiveness of the practices was assessed through two main criteria: first through the water to milk intake ratio, and the waste volume coefficient. Both parameters characterise the plant efficiency in regard of water consumption and water reuse. Information on cleaning chemical usage and recovery was also assessed as part of the review. Significant discrepancies emerge between the plants first due to the products manufactured and water reuse possibilities available in each plant. Second the type of treatment technologies used for condensate and cleaning solution influences the figures. One of the investigated plants is almost self-sufficient for water, emphasising the benefits gained from the use of technologies like membrane separations for condensate and cleaning solution treatment. In some cases, less cost-intensive technologies such as a clarifier are successful to improve cleaning agent recovery.

Patients undergoing procedures under general anaesthesia as day cases are routinely given a set of instructions regarding activities to avoid in the first 24 h after discharge. Day surgery units generally specify the need for a responsible carer from time of discharge for a period of 24 h. This study looks at the compliance of 240 patients with postoperative instructions. Of the patients studied, 4.1% drove, 1.7% made important decisions, 3.3% drank alcohol, 0.8% took sedatives and 10% cooked, ironed or looked after children. All patients were discharged into the care of a responsible adult. However, 13.3% failed to have a carer with them for 24 h and 1.3% spent the night alone at home. Of our cohort, 25% were unable to comply with the postoperative instructions in full. The majority of non-compliance occurred on the day following surgery, suggesting that patients may feel that the advice is excessively cautious.

The advent of ultra-fast (half-cycle), compact, remote controllable and cost effective circuit breakers suitable for deployment on rural lateral lines provides opportunities for new approaches to protecting these lines. This paper will present a novel scheme that provides significant benefit to operators of rural overhead MV distribution networks in terms of reliability improvement and minimizing the risk of electrical faults causing ignition of wild fires. Firstly, the key criteria for reliability optimization and mitigation of electrical faults causing ignition of fires are presented. An assessment of the performance of a number of typical lateral line protection schemes is conducted. All traditional approaches have a number of deficiencies, primarily related to preventing wild fires. New ultra-fast circuit breaker technology is introduced that enables a new approach to the optimal protection of rural lateral lines. A novel protection scheme is presented and is shown to represent the optimal solution for both reliability performance and prevention of electrical faults causing wild fire ignition on extreme weather days. For fault levels typical on rural lateral lines, when switched off in less than a half cycle, there is inadequate energy in the arc to cause fire ignition. This alternate protection mode can be remotely commanded over SCADA to allow rapid network response to extreme weather. An example is presented to clarify the expected performance.

Pulsed Fourier-Transform (FT) ultrasonic spectroscopy has been developed for the purpose of studying 3 He at ultralow temperatures. Our method is analogous to pulsed FT NMR and possesses several advantages over conventional time-of-flight acoustic techniques. For use at low temperatures, the most significant advantage is the ability to observe the frequency spectrum while the temperature, pressure, and magnetic field may be independently tuned. More specifically, using longitudinal LiNbO 3 transducers operating both on- and off-resonance, we are able to study several broadband windows of frequency, namely 16-25 MHz, 60-70 MHz, and 105-111 MHz, The determination of the energy gap of 3 He-B is presented as an effective application, and other novel uses are discussed.

An investigational tetravalent combined measles, mumps, rubella, and varicella vaccine and measles-mumps-rubella and varicella vaccines at separate injection sites given at the same visit were evaluated with respect to safety and cell-mediated and humoral immune responses at 6 weeks and 1 year after vaccination. Varicella seroconversion rates and lymphocyte proliferation responses were 100% for both vaccine groups at 6 weeks and 1 year. However, the antibody titer to varicella was lower in the combined vaccine group at 6 weeks, but there was no statistical difference in cell-mediated immune responses. One-year geometric mean titers were not statistically different. Seroconversion rates for measles, mumps, and rubella were 100% for both vaccine at 6 weeks and 1 year. Long-term follow-up of these immune responses is planned.

A pocket computer has been programmed to control the rate of administration of insulin given to diabetic patients having open heart surgery. Twelve diabetic patients were studied. Five had coronary artery bypass grafting, and seven had heart valve surgery. During operation 122 out of 162 (75%), and post-operatively 291 out of 360 (81%) blood glucose concentrations were between 4.0 and 8.0 mmol l-1. Five hundred and fifteen values out of 552 (99%) were below 12.0 mmol l-1. There was no hypoglycaemia. The lowest measured blood glucose concentration was 3.7 mmol l-1. The computer is readily available, easy to use by inexperienced personnel, and cheap.

Sixty three 24 hour oesophageal pH studies were performed in children with known or suspected gastro-oesophageal reflux and their progress was followed for at least a year. Forty two studies were of children who were well at follow up who were not receiving medical treatment for gastro-oesophageal reflux, and had not required antireflux surgery. Twenty one studies were from children who were still on treatment for gastro-oesophageal reflux or had undergone antireflux surgery. The results were analysed using non-parametric statistics to assess the value of pH recordings in predicting which children were likely to have continuing problems. Sleep reflux (minutes/hour) and acid clearing time were the most highly significant variables (p less than 0.0005 and p less than 0.0001 respectively). The results suggest that either sleep gastro-oesophageal reflux of more than 6.4 minutes/hour or an acid clearing time of seven minutes or more are good predictors of the clinical outcome (specificity 88.1%, sensitivity 81.0%). Three of the five children with false positive results were under 10 months of age. Positive results in this age group should therefore be interpreted with caution.

SummaryAn open, multi-centre study was carried out to assess the ease with which a patient could be instructed to use the terbutaline ‘Turbohaler’ ('Bricany1 Turbohaler7 and whether benefit was obtained and technique still satisfactory 4 weeks later. Asthmatic patients not receiving oral steroids were eligible; 1.38 completed the study. There were consistent increases in PEFR and FEV 1 at the start and end of the study on using the ‘Bricanyl Turbohaler’. Over 80% of patients used it correctly in every respect fulfilling each of 8 criteria and 96% found it easy to use. It was easy to instruct patients to use the ‘Turbohaler’. patients continued to use it correctly after a month and obtained sustained benefit.

An automated litho-aware design migration solution has been implemented to enable designers to port existing IP layouts (custom, library, and block) to nanometer technologies while optimizing layout printability and silicon yield. With rapidly shrinking technology nodes, the industry consolidation toward fabless or fab-lite manufacturing, demand for second-sourcing and dramatic increase in cost of IP development, the automation of "vertical" (between nodes) and 'horizontal" (between chip manufacturers) migration becomes a very important task. The challenge comes from the fact that even within the same technology node design and process-induced rules deviate substantially among different IDMs and foundries, which leads to costly, error-prone and time consuming design modifications. At the same time, fast and reliable adjustments to design and ability to switch between processes and chip manufacturers could represent significant improvement to TTM, and respectively improving ROI. Using conservative rules (or restricted design rules) is not always a viable option because of the area, performance and yield penalties. The difficulty of migration is augmented by the fact that design rules are not sufficient to guaranty good printability, maximum process window and high yield. Model-based detection of lithography-induced systematic yield-limiting defects (a.k.a. hotspots) is becoming a vital part of the design-for-manufacturing flow for advanced technology nodes at 65nm and below. Driven by customer demand, a collaborative effort between EDA vendors provides a complete design-for-manufacturing migration solution that allows sub-65 nanometer designers to comprehensively address the impact of manufacturing variations on design yield and performance during layout migration. First, the physical hard IP is migrated from its existing 90nm process to a more advanced 65 and 45 nm processes, resulting in an area-optimized DRC-clean 65nm design retaining the original hierarchy to facilitate further editing and design verification the original hierarchy is maintained. Then, the design manufacturability is checked using a model-based hotspot detection solution, applying foundry-certified models . Along with hotspots, it is also critical for the hotspot detection tool to generate directives on how to modify the layout to fix hotspots and prevent creation of new hotspots. Several alternative fixing guidelines, ranked by amount of design perturbation, are generated to provide focus and maximum flexibility to the correction tool. The correction tool reads hotspot locations, severities along with the fixing guidelines, identifies area to be fixed and converts the fixing guidelines into geometry constraints. Correction is then done on each area while respecting design rules, managing ripple effects through multiple layers and maintaining the hierarchy. When all the corrections are completed areas that have been affected are identified to allow these to be incrementally checked by the lithography verification tool (LPC) and re-assembled. In case new or residual hotspots are detected, this fix-verify flow iterates over to converge on a DRC and lithography-compliant design. Usually no more than three iterations are needed to output hotspot-free, DRC and Lithocompliant design. We present the results of this fully automated lithography-aware migration flow on layout IPs ranging from 65 nm to 45 nm design and migrated across foundries. Results show substantial layout quality improvements, reduced design sensitivity to process variability by eliminating hotspots. Run-time and hotspot fixing performance are shown.

This presentation demonstrates one of Design-for-Man ufacturing (DFM) solutions where a combination of design rules and lithography analysis (NILS, MEEF, and PW) is used as a basis for physical design correction and optimization. A physical design flow typically includes RET/OPC and post-OPC verification (Silicon DRC) steps. Error markers, generated at the verification step, show locations of so-called “hot spots” which are lithographically sensitive, areas prone to silicon failures. In our approach “hot spots” are traced back to a design and the design has been optimized to make those areas manufacturable. “Hot spot” markers of a fl at post OPC layout are analy zed and categorized and only a unique instance of a “hot spot” is traced back to design hi erarchy and corrected. Layout correction and optimization is guided by litho analysis and design intent. A set of lithography specific local constraints is added to a set of global constraints (DRC rules). A constraint-solving engine generates a new version of the layout that is DRC correct and is now "lithography/OPC friendly”. Depending on a user accessible set of parameters, design correction could be done with or without polygons edge segmentation and without critical area increase. Different lithography technologies (such as immersion lithography with hyper NA) and different process models could be applied. Device electrical performance in conjunction with simulated and extracted silicon shapes is discussed. Layout correction is done on a minimum edge/polygon movement principle, which leads to DRC clean and LVS respectful solution. Keywords: DFM, hot spot, design rules, litho simulation, silicon DRC, design optimization

We have investigated the effect of four doses of remifentanil on the incidence of respiratory depression and somatic response at incision. Remifentanil was administered as a loading dose of 0.125, 0.25, 0.375 or 0.5 microgram kg-1 and at a maintenance infusion rate of 0.025, 0.05, 0.075 or 0.1 microgram kg-1 min-1, respectively, with an infusion of propofol 6 mg kg-1 h-1. Responses occurred in 88% of patients with remifentanil 0.025 microgram kg-1 min-1 compared with 30-40% in the other groups. Respiratory depression after incision increased from 6% with remifentanil 0.025 microgram kg-1 min-1 to 73% with 0.1 microgram kg-1 min-1. Increases in propofol infusion rate to 7.2-8.4 mg kg-1 h-1 produced adequate maintenance of anaesthesia. Reductions in remifentanil doses to 0.025-0.05 microgram kg-1 min-1 resulted in adequate respiration at the end of surgery in 88% of patients. Maintenance infusions of the two drugs for spontaneous ventilation are likely to be in these ranges. However, the ideal loading doses and infusion rates for induction remain to be established.

Occupational exposure to blood and body fluids and the prevalence of serological markers of hepatitis B virus (HBV) infection were studied in Gloucestershire firemen to assess the occupational risk of HBV infection. A high compliance was achieved (472/503, 94 per cent). Cumulative occupational exposure to blood or body fluids rose progressively to 68 per cent after 24 years' service. No sera were positive for hepatitis B surface antigen (HBsAg). Six sera were positive for hepatitis B surface antibody (anti-HBs) and were tested for hepatitis B core antibody (anti-HBc). The four subjects who were positive for anti-HBs alone had all received HBV vaccine. Two sera contained both anti-HBs and anti-HBc. Therefore, 2/472 firemen (0.42 per cent) showed evidence of previous HBV infection, a similar proportion to that found in a recent study in UK blood donors (0.49 per cent). Despite considerable exposure to blood and body fluids, an occupational risk of hepatitis B infection was not found in Gloucestershire firemen.

The first reports of the measurement of Total Body Nitrogen (TBN) by In Vivo Neutron Activation Analysis (IVNAA) using a cyclotron date from the early 1970’s (Harvey et al., 1973). By the late 1970’s other laboratories were using the prompt gamma IVNAA technique with isotopic neutron sources (Mernagh et al., 1977; Vartsky et al., 1979a). The prompt IVNAA method is a relatively simple, non-invasive test which requires approximately 20 minutes of the patient’s time. The radiation dose is minimal, and both capital and running costs are small. Clinically, Total Body Protein (TBPr) can be reliably estimated from TBN (TBPr = 6.25 × TBN). The many clinical applications of the technique are described by Wahlqvist and Marks elsewhere in this volume, and by McNeill (1988). It is therefore surprising that so few hospitals are currently using the technique.

Oesophageal achalasia is uncommon in children and in its familial form it is a rarity. The presentation and management of two male siblings who presented with oesophageal achalasia as infants are reported. A high degree of consanguinity in the parents of the children existed, suggesting autosomal recessive transmission.

Two mothers who had asymptomatic rubella infection in pregnancy gave birth to severely affected infants. In both, the presence of preexisting antibody was well documented, although it could not be established whether it was the result of vaccine or natural infection.

We study theoretically the flow of a viscous incompressible fluid in a parallel-walled channel: the flow is driven by uniform steady suction through the porous and accelerating walls of the channel. Previous authors have discussed special cases of such flows, confining attention to flows which are symmetric, steady and two-dimensional; a similarity form of solution is assumed, as used by Berman and originally due to Hiemenz, to reduce the Navier–Stokes equations to a nonlinear ordinary differential equation. We generalize their work by considering asymmetric flows, unsteady flows and three-dimensional perturbations. By use of numerical calculations, matched asymptotic expansions for large values of the Reynolds number, both positive and negative, and the theory of dynamical systems we find many more exact solutions of the Navier–Stokes equations, examine their stability and interpret them; although much of the theory is for the general case, most of the numerical calculations are for the case of zero suction. In particular we show that most of the previously found steady solutions are unstable to antisymmetric two-dimensional disturbances. This leads to a pitchfork bifurcation, stable asymmetric steady solutions, a Hopf bifurcation, stable time-periodic solutions, stable quasi-periodic solutions and chaos in succession as the Reynolds number increases from zero, and a pitchfork bifurcation, stable asymmetric steady solutions, a Hopf bifurcation, periodic solutions, chaos via period doubling, other periodic solutions and chaos in succession as the Reynolds number decreases from zero.

Summary Rapid recognition and appropriate therapy will prevent or remediate most of the complications occurring in children after cataract aspiration and IOL implantation. Some of the complications of pediatric IOL implantations are related to the increased scleral pliability and decreased rigidity which predispose scleral collapse, vitreous loss, flat anterior chamber and corneal endothelial damage. A second group of complications is associated with the enhanced inflammatory and fibrotic responses peculiar to a child's eye. This group includes operative striate keratitis and iridocyclitis, late IOL precipitates, secondary and postpseudophakos membranes, iris erosion and synechiae formation, and IOL tilt and displacement. Although the intraocular lens is a possible means of visual rehabilitation for children with traumatic cataracts or unilateral infantile cataracts, its long-term risk/benefit ratio must still stand the test of time.

Four cases of malignant hyperphenylalaninemia (MHPA) are described. Pretreatment serum phenylalanine levels were 1.5, 3.0, 2.4, and 0.9 mmoles/l. Dihydropteridine reductase (DHPR) deficiency was proven in one patient by assays on cultured fibroblastic cells and was presumed in her sibling and in another deceased patient whose parents' fibroblastic cells show approximately 50% of normal enzyme activity. DHPR and phenylalanine hydroxylase deficiency were excluded by assays on liver obtained at autopsy in the 4th patient. Parenteral administration of tetrahydrobiopterin (BH4) corrected the hyperphenylalaninemia and increased the levels of catecholamines and 5-hydroxy-indoles in the one patient studied in life, but BH4 did not reach the cerebrospinal fluid. A 3-wk course of BH4 therapy had no clinical effect. Oral biopterin was absorbed and excreted in the urine, but did not alter the serum phenylalanine level. The frequency of MHPA in Australia was estimated as 7 in 258 patients with phenylketonuria.

We have developed and interfaced to a computer an automated instrument (the AMAC III) which is designed to observe simultaneously several physical parameters of cells. Typical parameters include electronic cell volume (Coulter effect), RF amplitude (opacity), multiwavelength fluorescence of cytological stains, and cell light-scattering. The use of a new ultraviolet laser combined with a holographic grating spectrograph promises to increase the number of fluorescing species that can be detected simultaneously. This number can be further increased by use of special rare-earth-based fluorochromes, that emit well-defined, spectrally distinct peaks.

Two approaches to the development of a true automated multiparameter analyzer for cells, AMAC, are discussed. The AMAC IV uses a water immersion lens mounted downstream from a Coulter Orifice for optical measurements. Although this type of device has a very high numerical aperture (0.70) and optimum light scattering characteristics, it is very difficult to minimize the distance between the objective and the orifice, and increasing this distance results in trajectory irregularities of the cells, with the possibility of exchange of sequence of cells between the orifice and the optical sensing zone. The other, the AMAC III, which is the optimal solution to this problem, performs the optical and electronic measurements simultaneously. This transducer is a small square orifice fabricated out of quartz, with sensing electrodes located at both ends. This combined electro-optical transducer has been used for fluorescence, electronic cell volume and opacity (AC amplitude divided by DC amplitude) measurements. Diffraction effects due to the orifice appear minimal and should not interfere with the scattering produced by the cells. Previous studies with a round but otherwise electronically similar orifice have indicated that it was possible to determine the shift in phase produced by the presence of a particle in the orifice. The capacity to measure all of these parameters simultaneously will greatly enhance the reliability of flow cell analysis.

An experiment is described in which the picosecond temporal structure of a Cerenkov radiation source has been measured using an optical streak camera. Electrons in the Stanford Linear Accelerator Center (SLAC) three kilometer linear accelerator, bunched by the 2856 MHz acceleration fields, are used to generate Cerenkov radiation in a helium-filled gas cell. We show that it is possible to construct a Cerenkov cell which introduces subpicosecond time spread and allows for nondestructive monitoring of the electron beam.

Describes an experimental system used to demonstrate changes in nor-adrenaline release from cells in culture caused by a pulsed magnetic field. The equipment was designed to facilitate a study of the mechanisms of the interaction between the field and the cells by subjecting the cells to a well defined stimulus.

The overnight respiratory patterns of 25 infants at high risk and 42 infants at low risk of sudden unexpected death were studied during the first 6 months of life. 'Risk' was determined using the birth scoring criteria of Carpenter and Emery. Recordings were made at home using a twin-channel radar chest movement detector which was designed to avoid the need for contact with the infant. The recordings were analysed for respiratory frequency, total duration of apnoea, periodic breathing, duration of regular breathing, and amount of body movement. The high risk group of infants showed respiratory frequencies that were significantly higher than those of the low risk group. None of the other parameters showed significant differences between the groups. These findings do not support the widespread use of home apnoea monitors for infants.

Seven patients with bronchial asthma requiring continuous medication were subjected to eight weeks of nocturnal exposure to negatively ionized air, and their progress was followed using objective tests of lung function and clinical assessment. During exposure, four patients showed significant increases in morning PEFR, which in two of these patients was not sustained when exposure ceased. In two patients the observed increase in PEFR was accompanied by subjective improvement. From the results of all our assessments we conclude that, although this treatment may lead to an improvement in some patients with asthma, further objective studies are required to determine the value of negatively ionized air in the routine management of asthma.

Two types of radiation monitor are described, which are of use in reducing the exposure of personnel in contact with radioactive substances. A pocket monitor for nurses working on radium wards is described which gives an audible indication when the dose-rate exceeds 30 mr per hour. A description is also given of a radiation level indicator which sounds an alarm when the radiation level at the apparatus exceeds a preset value.

A radiation detector in the form of a shielded p-n junction is described. The junction with the appropriate shielding is quality independent over the range 0?8 to 14 mm cu H.V.T. to better than 10%, and, with the instrumentation described, the output voltage is proportional to the incident dose rate (to within 5%) over the range 0?3 to 750 r/min. Also described are the temperature and polar responses, as well as measurement of radiation damage from 60Co ?-rays. A comparison is made between the p-n junction detector and a cadmium sulphide probe. The development of probes of smaller physical dimensions and to measure lower dose-rates, is discussed.

In the literature on the prevention of diabetes one finds attention drawn to the fact that heredity, race, and obesity are among the important factors that influence the development of this disease. If one could choose a mate with no diabetic taint in the family and not develop obesity the incidence of diabetes could be appreciably reduced. Strome and Blaine (1) point out that mortality rates from diabetes are higher in the United States than in any other major civilized country and that these are increasing every year. In 1933 the author (2) suggested that if one could diagnose diabetes before it became clinically apparent and could treat the disturbance successfully a considerable step forward in reducing the incidence and mortality of this disease would be achieved. The author has previously reported (3) that approximately 15 per cent of patients of college age having glycosuria on one examination would have some degree of disturbance of carbohydrate metabolism as judged by routine glucose tolerance tests.

A simple, inexpensive turbidity system is described which enables growth of a bacterial culture to be recorded automatically over long periods. The system responds linearly to changes in bacterial concentration over a hundredfold range, up to fully grown cultures; this provides an adequate range for most purposes. The system is versatile and can be expanded to a multi-channel system for simultaneously recording growth in different conditions by using individual tubes and recording the output on a multi-channel potentiometer recorder or a digital voltmeter with print out.