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This study assessed the levels of heavy metals in the soils of three communities (Lokoja, Osara, and Kabba) within forty kilometers from a Cement factory situated in Obajana, Kogi State of Nigeria. Soil pH values ranged from 6.0 - 7.3, organic matter ranged from 2.5±0.5-4.03±0.3 %, Electrical Conductivity ranged from 104.1±31.5-188.5±75.5 µS/Cm, carbonates ranged from 2.8±0.8-3.7±0.5 mg/kg. The order of pollution of the locations under study was Lokoja > Osara > Kabba > Control based on the Pollution Load Index calculation. The elements’ dominance was in the order: Zn >Pb >Cu> Ni > Cd in general. Lokoja: Zn-31.32, Pb-30.78, Cu-28.12, Ni- 22.723, and Cd-1.63 mgkg-1 Osara: Cu-22.32, Zn-21.56, Pb-16.31, Ni- 3.61, and Cd-1.16 mgkg-1 Kabba: Zn-17.98, Cu-6.05, Pb-5.89, Ni- 4.70, and Cd-1.105 mgkg-1. Higher elemental concentrations were observed in Lokoja and Osara. The I-geo results indicated that the Cu and Ni were moderately to strongly polluted metals in Lokoja with I-geo 4.15 and 3.84 respectively, while Cu I-geo= 1.85), and Ni (I-geo=1.59) in Kabba and Cd (I-geo=1.93), Ni (I-geo=1.18) and Pb (I-geo=1.67) were moderately polluted. However Zn was, according to the I-geo values, unpolluted both in Kabba and Osara but moderately polluted in Lokoja. The PLI values ranged from 2.04 to 6.3 indicating that some of the studied metals exceeded the background (Control) metal concentration. The mathematical models revealed that the source of pollution was anthropogenic, the cement facility together with the attendant vehicular traffic and emissions were implicated as responsible for metal pollution in these areas.

In this paper, we have presented the experimental results of phosphorus diffusion in silicon for the cases of rapid thermal processing (RTP) and rapid photothermal processing (RPP). In the case of the RPP, other than thermal energy, the vacuum ultraviolet photons are used as an additional source of energy. We have investigated the secondary-ion-mass-spectroscopy impurity profiles at different concentrations of P in Si. Based on our own experimental results and the data published in the open literature, we have provided an explanation of the enhanced diffusion both for the RTP and RPP cases. The thermal factor leads to the excitation (vibration) of atoms and quantum energy to the electron system excitation. As compared with the pure thermal process, the quantum-energy contribution provides a reduced activation energy and a higher diffusion coefficient.

The traditional caries index, DMF, provides inadequate information to assess dental treatment needs of a community. Dental health planners are often called upon to estimate the treatment needs, costs, time and personnel required for a proposed programme. A treatment needs index (TNI) is presented which provides important data for dental health planning. The index defines seven basic levels of treatment: (0) no treatment needed; (1) preventive treatment; (2) fissure sealants; (3) initial conservative restorations; (4) moderate conservative restorations; (5) advanced conservative restorations; and (6) radical treatment, including pulp therapy, prosthetic restorations and extractions. A pilot study and an example comparing data of both DMF and TNI demonstrates the values of the latter index. The Treatment Needs Index provides a more accurate description of caries severity and extent than does the traditional DMF index, and can be used to estimate the time required to treat a community.

Purpose: The objective of this study was to report on the survival rate of 16 patients treated with extraoral implants in the auricular region, analyze treatment outcomes, and discuss important clinical variables encountered during treatment. Materials and Methods: Sixteen patients who received extraoral dental implants to retain auricular prostheses between 1987 and 2003 were followed retrospectively. The variables recorded were gender, initial diagnosis, number and size of implants, implant placement date, age at implant placement, history of radiation to the treated field, abutment size, design of initial prosthesis, age of initial prosthesis (when a remake was indicated), date of prosthesis delivery, soft tissue response, grafting procedure, date of last follow-up, and complications. All patients were thoroughly evaluated presurgically by the reconstruction team, which consisted of prosthodontists, a facial prosthetist, and an otolaryngologist. Surgical templates were used for all patients. The criteria for success of the prostheses included marginal accuracy, overall stability and function, symmetry/position, texture, color stability, and patient acceptance. Results: Thirty-nine implants were placed in 16 patients. All 16 patients were completely satisfied with their reconstructions. No surgical complications, implant failures, or prosthetic failures were encountered. Therefore, the survival rate was 100%. Three patients (18.75%) had grade 0, seven (43.75%) had grade 1, five (31.25%) had grade 2, and one (6.25%) had grade 3 soft tissue inflammation. The inflammation completely resolved in 7 of the 13 patients (54%) with hygiene reinforcement or soft tissue reduction. Conclusions: The survival rate for bone-anchored titanium implants and prostheses was 100%. Bone-anchored titanium implants provided the 16 patients in this study with a safe, reliable, adhesive-free method to anchor auricular prostheses with recovery of normal appearance. Under the guidance of an appropriate implant team, proper positioning of implants was optimized to allow prosthodontic rehabilitation using implant-retained prostheses.

Noncoherent Doppler tracking has been devised as a means to achieve highly accurate, two-way Doppler measurements with a simple, transceiver-based communications system. This technique has been flown as an experiment on the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) spacecraft, (launched 7 December 2001), as the operational technique for Doppler tracking on CONTOUR, and is baselined on several future deep space missions at JHU/APL. This paper reports on initial results from a series of successful tests of this technique between the TIMED spacecraft and NASA ground stations in the Deep Space Network. It also examines the advantages that noncoherent Doppler tracking and a transceiver-based system may offer to small satellite systems, including reduced cost, mass, and power.

High-quality DuPont screen-printed Ag contacts were achieved on high sheet-resistance emitters (100 /spl Omega//sq) by rapid alloying of PV168 Ag paste. Excellent specific contact resistance (/spl sim/1 m/spl Omega/-cm/sup 2/) in conjunction with high fill factor (FF) (0.775) were obtained on 100 /spl Omega//sq emitters by a 900/spl deg/C spike firing of the PV168 paste in a belt furnace. The combination of the alloying characteristics of the PV168 Ag paste and optimized single-step rapid low-thermal budget firing resulted in a cost-effective manufacturable process for high-efficiency Si solar cells. In addition, the co-fired 100 /spl Omega//sq cell showed a noticeable improvement of /spl sim/0.5% in absolute efficiency over a conventional co-fired 45 /spl Omega//sq emitter cell. Lighter doping in the 100 /spl Omega//sq emitter cell resulted in better blue-response compared to the conventional cell, contributing to /spl sim/1.3 mA/cm/sup 2/ improvement in short-circuit current. Improved surface passivation on 100 /spl Omega//sq emitter cell resulted in additional 0.6 mA/cm/sup 2/ increase in J/sub sc/, 15-mV higher V/sub oc/, and a 0.6% increase in absolute cell efficiency. Front grid design optimization resulted in a FF of 0.780, and a further improvement in cell efficiency to reach 17.4%.

This research details the development of technologies and methodologies that enable distributed spacecraft systems by supporting integrated navigation, communication, and control. Operating at the confluence of these critical functions produces capabilities needed to realize the promise of distributed spacecraft systems, including improved performance and robustness relative to monolithic space systems. Navigation supports science data association and data alignment for distributed aperture sensing, multipoint observation, and co-observation of target regions. Communication enables autonomous distributed science data processing and information exchange among space assets. Both navigation and communication provide essential input to control methods for coordinating distributed autonomous assets at the interspacecraft system level and the intraspacecraft affector subsystem level. A technology solution to implement these capabilities, the Crosslink Transceiver, is also described. The Crosslink Transceiver provides navigation and communication capability that can be integrated into a developing autonomous command and control methodology for distributed spacecraft systems. A small satellite implementation of the Crosslink Transceiver design is detailed and its ability to support broad distributed spacecraft mission classes is described.

The band gap of Ga0.5In0.5P is reported as a function of doping level and growth rate. The lowest band gaps are obtained for hole concentrations of about 2 × 1017 cm−3. For samples doped p-type above 1 × 1018 cm−3, the band gap increases dramatically, regardless of growth rate. This effect is shown to be the result of disordering during growth rather than a change in the equilibrium surface structure with doping. The doping level dependence of the band gap of Ga0.5In0.5P samples grown at higher and lower growth rates differs for selenium and zinc doping even though the effects of high doping are the same for both dopants.

Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease. Methods of dental treatment of a young male patient with ALS are presented. This case is unusual in several respects: the early age of onset, the long survival time, and the period of time in which the case was followed in our dental clinic. Aspects of ALS which are of concern to dentistry, as related to clinical care and strategies for effective oral health delivery, are presented.

The doping‐dependent, near‐band‐edge optical‐absorption coefficient α(hν) was deduced from optical transmission measurements in n‐type GaAs thin films. The selenium‐doped films were grown by metalorganic chemical‐vapor deposition and doped to produce room‐temperature electron concentrations from 1.3×1017 to 3.8×1018 cm−3. The transmission measurements covered photon energies between 1.35 and 1.7 eV and were performed on double heterostructures with the substrate removed by selective etching. The results show good qualitative agreement with previous studies and good quantitative agreement, except for the heavily doped samples. For n0=3.8×1018 cm−3, α(1.42 eV) is approximately four times that reported by previous workers. Secondary‐ion‐mass spectrometry measurements on films grown under differing conditions demonstrate that α(hν) is sensitive to electrically inactive dopants and supports the hypothesis that precipitates or compensation influenced previous measurements. These comprehensive results on high‐qu...

One of the steps in creating a mathematical model of a system is to test the model after it has been fully specified, to see whether it is performing adequately. Often, it is found that the model is not performing acceptably (e.g. the model is not giving accurate predictions of the performance of the actual system). The same lack of fidelity can also be observed in established models that had been performing well, indicating a change in the actual system. At this point, it is necessary to diagnose where the problem in the model lies; a process called error isolation. An error isolation technique for detecting the misspecified parameter (or set of parameters) is described. This technique is especially designed for use on state-space models of large-scale systems. The authors report on an example of an application of the methodology to localizing errors in the model of an inertial navigation system. >

Modifying a Super-Sep bottle by adding a brush to the lid for paint-on use allows for the precise application of the separating medium used when flasking dentures. Super-Sep offers many advantages over other commonly used separating mediums: It is virtually dimensionless, allowing for better accuracy; it dries quickly and functions best on moist stone; and it can be poured against immediately. The latter fact means less time is needed before the subsequent layers of stone can be applied when denture flasking. (J Prosthet Dent 2001;85:415-7.)

Heavily doped GaAs layers for high conductance GaAs tunnel junctions have been grown by atmospheric pressure organometallic vapor phase epitaxy (OMVPE) using Zn as the dopant for thep + regions and either Se or Si as the dopant for then + regions. At a growth temperature of 700° C using a “cycled” growth technique for the Zn-dopedp ++-GaAs layer, both the conductance and the peak current density of the tunnel diode has been increased by a factor of ∼65 compared to a tunnel junction with a continuously grown Zn-doped p+-GaAs. The conductance of the tunnel junction, which is maximized at a growth temperature of 650° C using cycled growth, is comparable to the best reported values for tunnel junctions grown by molecular beam epitaxy. Cycled growths forn + Se-doped regions are found to reduce the conductance of a tunnel junction by more than two orders of magnitude. However, cycled growth for the n+-GaAs regions with Si doping show no conductance degradation. A model based on incorporation sites of these dopants during OMVPE growth of GaAs is presented to account for the experimental observations.

The use of copper during the fabrication of CdTe solar cells is a common feature for nearly all processing schemes developed for these devices. Copper is typically introduced in CdTe during the application of the back electrode, to enhance device performance by facilitating the formation of an ohmic back contact. However, Cu has also been associated with observed instability in CdTe. For this work, although Cu was utilized during the cell fabrication process, it was eliminated from the back contact formation step, and instead introduced in the CdS film prior to the deposition of the CdTe. The only fabrication step, where Cu was intentionally introduced, was subsequent to the CdS deposition. Both plain graphite and Sb/sub 2/Te/sub 3//Mo were used as back contacts. Solar cell results suggested that ohmic contacts to CdTe can be attained with undoped graphite as the back electrode. For devices contacted with plain graphite V/sub OC/'s and FF's in the range of 800-830 mV and 63-67% have been obtained. For Sb/sub 2/Te/sub 3/-contacted cells, the incorporation of Cu in CdS has lead to a significant increase in performance even though a back barrier was present in these cells.

The immediate prosthetic rehabilitation of a patient with erosive cutaneous cytomegalovirus (CMV) is presented. Although CMV is a major cause of morbidity and mortality in immunocompromised patients, skin lesions are rarely discussed in the literature. Recognition of the susceptibility of medically compromised patients to infections that can cause extraoral and intraoral deformity is essential to prevention, early diagnosis, and prompt intervention of a life-threatening destructive debilitation. A method for rapidly fabricating a nasal prosthesis is described, and the importance of prompt esthetic and psychological rehabilitation is reviewed.

Distributed spacecraft systems concepts have been developed to leverage the inherent advantage of multiple, redundant sensing assets, including expanded capability, improved robustness, and graceful functional degradation. Both military and civilian missions have been advanced, with near-term technology demonstration efforts designed to serve as pathfinders to fully capable systems to meet future challenges. Distributing capability among multiple platforms, however, results in a fundamental increase in the complexity of coordinating and operating space systems due to delays in state knowledge and the need to integrate individual spacecraft autonomy within the broader system context. At the same time distributed spacecraft systems typically require added capabilities relative to monolithic spacecraft designs, such as command and control architectures that support diverse communication channels for functions such as crosslink communication and relative navigation measurements. The importance of these additional capabilities is particularly evident in relative navigation functionality, which in many systems may dominate absolute orbit determination requirements. This work describes a technique to address the fundamental need for relative navigation among distributed space assets that focuses on a minimalist hardware implementation that is suited for microsatellites, rovers, and other potential physically limited systems. Test results are provided from experiments implemented on The Johns Hopkins University Applied Physics Laboratory's crosslink transceiver (CLT) operating as a crosslink communication and navigation system in a time-division multiple access modes. To address the coordination and operation of a distributed spacecraft system under conditions that require capabilities such as regular relative navigation and communication, a flight autonomy architecture is defined that specifically addresses the complexities of controlling multiple, distributed assets. This architecture is based on the use of model-based programming and discrete event systems that use explicit logic models of spacecraft hardware and software components coupled with high-level control strategy specifications.

This research details the development and performance of the crosslink transceiver, an integrated navigation and communication system that enables distributed spacecraft system operations. The crosslink transceiver is a modular, extensible system that supports science operations among multiple, distributed space assets by implementing the essential functions of navigation, communication and control. Distributed spacecraft systems, also called formation flying systems, extend the capabilities of single-spacecraft missions by providing a platform for complex sensing tasks, including multipoint observation, co-observation, and distributed apertures. To accomplish these tasks, such systems rely on the ability to communicate science and coordination information, to determine relative position, velocity and time for command and control operations, and to operate in a coordinated manner to achieve common mission goals. The utility of the crosslink transceiver to support these operations is established by demonstrating its applicability to near-term science and military missions.

Data are presented for the Zn doping of Ga/sub 0.5/In/sub 0.5/P, showing that the hole and zinc concentrations increase almost linearly with zinc flow, and also increase with the V/III ratio and growth rate at a fixed V/III ratio. These observations are consistent with other reports that show the incorporation of zinc to increase with growth rate in GaAs deposition and either increase or remain constant with the V/III ratio for both GaAs and Ga/sub 0.5/In/sub 0.5/P deposition by metal-organic chemical vapor deposition (MOCVD). A model based on varying group V coverage of the step where zinc is most strongly bound is presented and compared with the data. The model explains the increase in zinc incorporation with both the growth rate and the V/III ratio. >

This article demonstrates the use of denture adhesive to retain a wax pattern during trial placement of an extraoral facial prosthesis. Using denture adhesive in this manner easily and temporarily retains the wax pattern in place without visual obstructions such as hands or instruments holding the pattern in place. With the wax pattern held securely in place, the clinician is able to assess it from all angles for position, esthetics, margin extension, and tissue movement before the wax pattern is finalized and processed.

This research details the development of technologies and methodologies that enable distributed spacecraft systems by supporting integrated navigation, communications, and control. The utility of operating at the confluence of navigation, communications, and control is established by demonstrating that such an approach enables fundamental operations needed to realize the promise of distributed spacecraft systems, including improved performance and robustness relative to monolithic space systems. Navigation is needed to support science data association and data alignment for distributed aperture sensing, multipoint observation, and co-observation of target regions. Communications enables autonomous distributed processing of science data. when required, and provides the infrastructure to support information exchange among space assets. Both navigation and communications, in turn, provide vital input to control methodologies for coordinating distributed autonomous assets at both the interspacecraft system level and the intraspacecraft affecter subsystem level. The development of a technological solution to implement these capabilities, the Crosslink Transceiver, is also described. The Crosslink Transceiver provides a navigation and communications capability that can be integrated into a developing autonomous command and control methodology for distributed spacecraft systems. A small satellite implementation of the Crosslink Transceiver design is detailed, including baseline physical characteristics and fundamental performance requirements. The ability of the subsystem to support broad classes of distributed spacecraft campaigns is described.

An important device issue that must be addressed for the use of CdTe solar cells in terrestrial applications is the formation of an effective and reliable back contact. Most successful efforts to date have been relying on the use of copper either in elemental form or in conjunction with other materials. Two examples are copper doped zinc telluride and copper telluride. Such efforts have yielded CdTe solar cells with state-of-the-art fill factors (>75%). However, the long-term stability of copper-based contacts is believed to play a major role in the observed performance degradation of CdTe/CdS solar cells. Nickel phosphide (Ni/sub 2/P) has been considered as an alternative back contact material. Nickel phosphide in powder form was mixed with a graphite paste and subsequently applied to CdTe for the formation of the back contact. Cadmium telluride solar cells were fabricated using this type of contact and the effect of various processing parameters such as annealing temperature, duration of annealing, and Ni/sub 2/P concentration have been studied. The best devices exhibited V/sub oc/s in the range of 820-840 mV and FFs greater than 70% indicating that Ni/sub 2/P is a very promising candidate as a back contact material for CdTe solar cells.

Background Methotrexate (MTX) is widely used as a disease modifying agent in rheumatic disease. 1 The National Patient Safety Agency (UK) have previously highlighted the potential hazards of MTX therapy and requested that National Health Service (NHS) organisations ensure that MTX is monitored effectively and safely. 2 The necessity for close monitoring with regular blood tests is twofold; to monitor for adverse effects and secondly to help evaluate response to treatment. Objectives Our objective was to assess the impact that the introduction of a shared care scheme with General Practitioners (GPs) has had on MTX monitoring efficacy. Under this scheme, the GP is responsible for the all aspects of blood test monitoring for the patient while they are on MTX. Methods Fifty patients were randomly selected from our internal database of patients on the shared care scheme. The British Society of Rheumatology (BSR) guideline for MTX monitoring was used as our standard. 3,4,5 A retrospective analysis of all blood test monitoring over the preceding 6 months was undertaken. Results obtained were compared to 4 other data series9 from rheumatology departmental blood test monitoring audits (2003, 2004 and 2007-2008). Results See Table. There is a clearly demonstrable and consecutive improvement in adherence to BSR guidance since 2003. An interesting subgroup analysis of our cohort demonstrates that 38% of patients had blood test monitoring at a frequency above the recommended minimal standards in 2013. This was substantially higher than previously observed in earlier data collections. Conclusions There is marginally improved adherence to monitoring in the shared care scheme, versus the last cohort of patients who had departmental monitoring (2007-2008). This suggests that the new shared care scheme is certainly non-inferior and possibly slightly superior to departmental monitoring. It may be postulated that the patients being over-monitored are having blood tests for separate purposes entirely or opportunistically when blood tests are indicated for an unrelated issue, or both. Our data would suggest that the majority of patients established on DMARD therapy can have their blood tests monitored successfully by GPs under shared care schemes. By encouraging and empowering GPs to participate in shared care monitoring schemes, NHS costs and resources could potentially be significantly reduced. Furthermore, the gap between primary and secondary care could be bridged, with patients ultimately benefiting from a more optimal level of drug monitoring and a more collaborative approach to care. Should such schemes be utilised more widely? References Methotrexate Drug Monograph. Martindale: The complete Drug Reference. The Pharmaceutical Press 2007. www.medscape.com Improving Compliance with Oral Methotrexate Guidelines. National Patient Safety Agency (NPSA)/2006/13; 1 June 2006 British National Formulary (BNF) No 52 September 2006. Pharmaceutical Press National Guidelines for the monitoring of second line agents. British Society of Rheumatology; p7; July 2000 accessed at www.rheumatology.org.uk BSR/BHPR guideline for DMARD therapy in consultation with British Association of Dermatologists. Chakravarty et al. Rheumatology 2008 Acknowledgements Dr Mark Pugh (Consultant Rheumatologist, St. Mary9s Hospital, Isle of Wight). Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.1311

The use of radiation shields in the head and neck cancer patient receiving adjuvant radiation therapy is a treatment alternative for protecting anticipated prosthetic implant sites. Shields can be fabricated easily as part of an interdisciplinary treatment protocol. In this article, the methods used to fabricate an extraoral radiation shield are described, and a patient treatment that illustrates possible uses of the shield for both extraoral and intraoral sites is presented.

SUMMARY This clinical report describes the treatment of apatient with Congenital Central Hypoventilation Syn-drome using a simple impression procedure and pros-thesis fabrication. Treatment required only the basicinformation provided by the otolaryngologist, mea-surements were taken at the initial appointment, andbasic skills were used in fabrication of intraoral andextraoral prosthetic devices. It is recommended that theclinical phase of this procedure be performed in thepresence of an otolaryngologist. Patients who live withthis syndrome have undergone many trials physically,emotionally, psychologically, and socially. The presenceof this type of prosthesis has many advantages such asallowance of speech without obvious air leakage, andbeing relatively inconspicuous. Compared with the WRIGHT ET AL THE JOURNAL OF PROSTHETIC DENTISTRY OCTOBER 1999 389 Fig. 5. Ten-year-old girl with CCHS with tracheostomal obtu-rator assembly in place. Prosthesis is esthetically pleasing topatient and held in place through bulb on terminal end ofobturator with beaded necklace.

Retention of a facial prosthesis is the most important factor in creating a useful prosthesis for the patient. This paper presents a detailed case study of an auricular defect that was rehabilitated using two types of prosthetic retention: adhesive and osseointegration. We present the patient selection criteria, the surgical considerations prior to implant placement, retention component selection, prosthetic fabrication techniques and patient management after prosthetic delivery. The osseointegrated prosthesis made a large improvement in the patient's quality of life.

Objective: To evaluate the effectiveness of the bone-anchored titanium implants in auricular reconstructions. Study Design: Six patients who received implants for an auricular reconstruction were followed prospectively. Four patients had lost their ears to cancer, and the other two had congenital aural atresia Methods: All patients were thoroughly evaluated by the reconstruction team, which included a surgeon, a prosthodontist, and a facial prosthetist. Three patients were evaluated audiologically for a bone-anchored hearing aid. Four patients received implants in a single-stage procedure, and two underwent a two-stage procedure. A gold bar with retaining clips was used to anchor the prosthetic ear in four patients, and magnets were used in the remaining two. Results: All six patients are completely satisfied with their reconstructions. No failures, extrusions, or bony complications were encountered. One patient had recurrent dermatitis, which subsided when his gold bar was replaced with magnets. Conclusion: Implanted under the guidance of an appropriate prosthetic team, bone-anchored titanium implants provide patients with a safe, reliable, adhesive-free method to anchor auricular prostheses with recovery of their normal appearance.

A procedure is described for the fabrication of a 3-dimensional surgical template to guide the placement of implants to retain an auricular prosthesis. This procedure requires a diagnostic wax pattern that is checked while on the patient to ensure it is positioned correctly and is also the correct size. The wax pattern is processed into a clear, methyl methacrylate resin, 3-dimensional surgical template. The most effective type of surgical template for planning implant placement is a 3-dimensional acrylic template that closely resembles the final prosthesis. This template will direct the implant placement where the retentive elements are most easily concealed, under the thickest areas of the prosthesis, which are the antihelix and antitragus. This location allows the best esthetic and functional results. An additional advantage of this technique is that it allows the retrieval of the diagnostic wax pattern of the auricle so that it can be used to fabricate the definitive prosthesis. (J Prosthet Dent 1999;81:228-33.)

We have investigated the effect of deposition conditions of SnO2 films, deposited by chemical vapor deposition using tin tetrachloride and tetramethyltin precursors, on the film properties. The type of precursor and the deposition temperature affect the morphology of the films. The structure of the films is determined by the deposition temperature: films deposited at low temperatures show a mixed SnO and SnO2 phase. The processing temperature and type of substrate determine the impurity content in the films. Electrical properties (e.g., the carrier mobility) and optical properties of the films are affected by the structure and the impurity content in these layers.

Experimental infection with hepatitis E virus (HEV) from Africa has not been investigated. Our purpose was to study hepatitis E produced by HEV from Chad (North Africa) and to analyze the genetic sequence of the HEV obtained after animal passage. An HEV-containing fecal sample from Chad was intravenously inoculated in four cynomolgus macaques. When serum Alanine Amino Transferase (ALT) levels rose, open liver biopsy and bile aspiration were performed. In all the monkeys, an ALT rise occurred 25 to 32 days after inoculation and new anti-HEV was detected by Enzyme Immuno Assay (EIA). Hepatic histopathology was consistent with acute viral hepatitis. HEV was detected by polymerase chain reaction (PCR) in bile (3/4 animals) and feces (2/4 animals) and by imunoelectron microscopy (IEM) in the inoculum and one bile specimen. A genetic variant HEV was identified in one monkey. The Chad HEV produced hepatitis E with pathophysiologic and histopathologic findings similar to those observed with HEV from other geographic origins. A genomic variant HEV population was produced after one passage in a macaque.

CdS/CdTe structures deposited on different substrates are analyzed using transmission electron microscopy (TEM), secondary ion mass spectrometry (SIMS), optical transmission, atomic force microscopy (AFM), X‐ray diffraction (XRD) and photoluminescence (PL). The microstructure of CdTe was found to be independent of CdS crystallinity, and the structural defects at CdS/CdTe interface are generated principally by the lattice mismatch between CdS and CdTe. The interdiffusion at the CdS/CdTe interface was found to be a function of substrate temperature and CdCl2 heat treatment.

High‐efficiency polycrystalline CdS/CdTe solar cells have been fabricated using CdTe absorber layers deposited by close‐spaced sublimation (CSS). CSS employs high substrate temperatures (Tsub) during film growth, which can promote the formation of larger grains and higher Voc’s yielding better device performance. However, as Tsub increases beyond 610 °C, voids or pinholes begin to form in the CdTe layer. When the back contact is applied, these voids serve as shunt paths that effectively lower Voc. In this fashion, benefits associated with higher substrate temperatures are seriously compromised. Concurrent with voiding is the observation that higher temperatures promote interdiffusion at the CdS/CdTe interface such that the effective thickness of the CdS layer is reduced. Variations in processing that correct for these detrimental effects have led to a total‐area device efficiency of 12%.

Cytokines IL-1-beta, IL-2, and TNF alpha were detected in occasional cells within portal inflammatory infiltrates beginning 3 weeks after oral inoculation of monkeys with HAV. The number of cells secreting those cytokines did not increase, and they were not of importance in the pathogenesis. Production of cytokines IL-6 and IL-4 by T lymphocytes infiltrating portal areas started 4 weeks after inoculation, stimulating local expansion of B cells, probably secreting antibodies to HAV. IL-6 and IL-4 may also stimulate cytotoxic activity of a few CD8+ lymphocytes.

Multiple physical impairments are associated with chronic drooling. This case illustrates the use of a simple appliance to align the patient's lip to provide opportunity for a lip seal when swallowing or at rest in a patient with a Class II malocclusion. The appliance resulted in a significant decrease in drooling in this patient.

In response to the need for dental office asepsis, many practitioners sterilize dental air/water syringe tips for each patient. It is hypothesized that repeated sterilization would lead to internal corrosion restricting the water flow. This study was conducted to evaluate consistency of water flow in a series of dental air/water syringe tips after multiple cycles of Chemiclave sterilization. An apparatus was constructed to deliver water at the same pressure and flow to each syringe tip. The flow rates between tips were significantly different (P.001). Average water flow, in grams per minute, was determined by ten repeat trials for each tip. The tips were retested after 1, 5, and 25 cycles of Chemiclave sterilization. None of tips showed a decrease in water flow efficiency after repeated sterilization cycles. No difference in ability to remove etchant from enamel and dentin could be demonstrated using a 10-second wash.

HIV infection can cause a variety of neuropsychiatric changes. These changes and their effects on dental care delivery are discussed. A case report illustrates the behavioral changes of one patient.

While rates of infection with the HIV virus are decreasing, the number of children infected continues to increase. There are multiple implications for the practicing pediatric dentist. Many of these children will seek or be referred by other health care providers for treatment of resulting oral pathology. Dentists must be prepared to provide dental services to the HIV-infected child.

This study compared symptom reports and cardiovascular reactivity of a group of 24 individuals recruited from the community who reported a cognitive or emotional symptom caused by at least one food (food-sensitivity reporters, FSR) vs those of 15 controls (C) without a history of food, chemical, drug, or inhalant sensitivities. The main findings were: 1) FSR indicated sensitivities not only to foods, but also to environmental chemicals, drugs, and natural inhalants, as well as significantly more symptoms than C in multiple systems; 2) more FSR than C noted recent state depression and anxiety, as well as higher trait anxiety on the Bendig form of the Taylor Manifest Anxiety Scale; 3) however, on multiple regression analysis, not only depression, but also the number of sensitivities (foods, chemicals, drugs, inhalants), accounted for part of the variance in total number of symptoms (38 and 17%, respectively), whereas none of the affective measures accounted for any of the variance in total number of sensitivities over all subjects; 4) after controlling for depression and anxiety, FSR still showed a trend toward poorer performance on a timed mental arithmetic task (p = 0.16); and 5) FSR and C showed opposite patterns of heart rate change to two different stressful tasks (mental arithmetic and isometric exercise) (group by task interaction, p < 0.05). The data are discussed in terms of a time-dependent sensitization (TDS) process that predicts a cross-sensitizing and cross-reactive role for xenobiotic agents (e.g., foods, chemicals, drugs, and inhalants) and for salient psychological stress in the expression of psychophysiological dysfunctions of FSR. As in other chronically ill populations, negative affect in food-sensitive individuals may explain greater symptom reporting, but not necessarily account for the illness itself. For either a food or a psychological stimulus to begin to elicit sensitized responses, e.g., marked physiological differences from C, FSR may require multiple, intermittent exposures spaced over 5-28 days rather than on only 1 day.