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ABSTRACTToday, more than ever, companies collect their customers’ Personally Identifiable Information (PII) over the Internet. The alarming rate of PII misuse drives the need for improving companies’ privacy practices. We thoroughly study privacy policies of 600 companies (10% of all listings on NYSE, Nasdaq, and AMEX stock markets) across industries and investigate 10 different privacy pertinent factors in them. The study reveals interesting trends: for example, more than 30% of the companies still lack privacy policies, and the rest tend to collect users’ information but claim to use it only for the intended purpose. Furthermore, almost one out of every two companies provides the collected information to law enforcement without asking for a warrant or subpoena. We found that the majority of the companies do not collect children’s PII, one out of every three companies lets users correct their PII but does not allow complete deletion, and the majority post new policies online and expect the user to check the privacy policy frequently. The findings of this study can help companies improve their privacy policies, enable lawmakers to create better regulations and evaluate their effectiveness, and finally educate users with respect to the current state of privacy practices in an industry.

Entities interacting on the web establish their identity by creating virtual personas. These entities, or agents, can be human users or software-based. This research models identity using the Entity-Persona Model, a semantically annotated social network inferred from the persistent traces of interaction between personas on the web. A Persona Mapping Algorithm is proposed which compares the local views of personas in their social network referred to as their Virtual Signatures, for structural and semantic similarity. The semantics of the Entity-Persona Model are modeled by a vector space model of the text associated with the personas in the network, which allows comparison of their Virtual Signatures. This enables all the publicly accessible personas of an entity to be identified on the scale of the web. This research enables an agent to identify a single entity using multiple personas on different networks, provided that multiple personas exhibit characteristic behavior. The agent is able to increase the trustworthiness of on-line interactions by establishing the identity of entities operating under multiple personas. Consequently, reputation measures based on on-line interactions with multiple personas can be aggregated and resolved to the true singular identity.

This article presents a capability called Adaptive Decision-Making Frameworks (ADMF) and shows that it can result in significantly improved system performance across run-time situation changes in a multi-agent system. Specifically, ADMF can result in improved and more robust performance compared to the use of a single static decision-making framework (DMF). The ADMF capability allows agents to dynamically adapt the DMF in which they participate to fit their run-time situation as it changes. A DMF identifies a set of agents and specifies the distribution of decision-making control and the authority to assign subtasks among these agents as they determine how a goal or set of goals should be achieved. The ADMF capability is a form of organizational adaptation and differs from previous approaches to organizational adaptation and dynamic coordination in that it is the first to allow dynamic and explicit manipulation of these DMF characteristics at run-time as variables controlling agent behavior. The approach proposed for selecting DMFs at run-time parameterizes all domain-specific knowledge as characteristics of the agents’ situation, so the approach is application-independent. The presented evaluation empirically shows that, for at least one multi-agent system, there is no one best DMF for multiple agents across run-time situational changes. Next, it motivates the further exploration of ADMF by showing that adapting DMFs to run-time variations in situation can result in improved overall system performance compared to static or random DMFs.This article presents a capability called Adaptive Decision-Making Frameworks (ADMF) and shows that it can result in significantly improved system performance across run-time situation changes in a multi-agent system. Specifically, ADMF can result in improved and more robust performance compared to the use of a single static decision-making framework (DMF). The ADMF capability allows agents to dynamically adapt the DMF in which they participate to fit their run-time situation as it changes. A DMF identifies a set of agents and specifies the distribution of decision-making control and the authority to assign subtasks among these agents as they determine how a goal or set of goals should be achieved. The ADMF capability is a form of organizational adaptation and differs from previous approaches to organizational adaptation and dynamic coordination in that it is the first to allow dynamic and explicit manipulation of these DMF characteristics at run-time as variables controlling agent behavior. The approach proposed for selecting DMFs at run-time parameterizes all domain-specific knowledge as characteristics of the agents’ situation, so the approach is application-independent. The presented evaluation empirically shows that, for at least one multi-agent system, there is no one best DMF for multiple agents across run-time situational changes. Next, it motivates the further exploration of ADMF by showing that adapting DMFs to run-time variations in situation can result in improved overall system performance compared to static or random DMFs.

This paper discusses infrastructure for design, development, and experimentation of multi-agent systems. Multi-agent system design requires determining (1) how domain requirements drive the use of agents and AI techniques, (2) what competencies agents need in a MAS, and (3) which techniques implement those competencies. Deployment requirements include code reuse, parallel development through formal standardized object specifications, multi-language and multi-platform support, simulation and experimentation facilities, and user interfaces to view internal module, agent, and system operations. We discuss how standard infrastructure technologies such as OMG IDL, OMG CORBA, Java, and VRML support these services. Empirical evaluation of complex software systems requires iteration through combinations of experimental parameters and recording desired data. Infrastructure software can ease the setup, running, and analysis of large-scale computational experiments. The development of the Sensible Agent Testbed and architecture over the past six years provides a concrete example. The design rationale for the Sensible Agent architecture emphasizes domain-independent requirements and rapid deployment to new application domains. The Sensible Agent Testbed is a suite of tools providing or assisting in setting up, running, visually monitoring, and chronicling empirical testing and operation of complex, distributed multi-agent systems. A thorough look at the various Sensible Agents infrastructure pieces illustrates the engineering principles essential for multi-agent infrastructure, while documenting the software for users.

Multi-agent systems require adaptability to perform effectively in complex and dynamic environments. This article shows that agents should be able to benefit from dynamically adapting their decision-making frameworks. A decision-making framework describes the set of multi-agent decision-making interactions exercised by members of an agent group in the course of pursuing a goal or set of goals. The decision-making interaction style an agent adopts with respect to other agents influences that agent's degree of autonomy. The article introduces the capability of Dynamic Adaptive Autonomy (DAA), which allows an agent to dynamically modify its autonomy along a defined spectrum (from command-driven to consensus to locally autonomous/master) for each goal it pursues. This article presents one motivation for DAA through experiments showing that the ‘best’ decision-making framework for a group of agents depends not only on the problem domain and pre-defined characteristics of the system, but also on run-time factors that can change during system operation. This result holds regardless of which performance metric is used to define ‘best’. Thus, it is possible for agents to benefit by dynamically adapting their decision-making frameworks to their situation during system operation.

Identification of craniofacial landmarks, particularly condylar anatomy, on the lateral cephalometric radiograph is erratic. The accuracy of recognition is critical for proper diagnosis of malocclusion and for assessing growth and orthodontic treatment. The aim of this study was to evaluate the identification of condylion and other cephalometric landmarks commonly used, or thought to be easily identifiable. A lateral cephalograph was taken on each of 34 adult subjects. Five examiners, three orthodontists, a dental radiologist and a second-year orthodontic resident rated the condyle, along with sella (S), nasion (Na), point A (A), infradentale (I), pogonion (Pog) and menton (Me) as identifiable, non-identifiable and interpreted. In addition, distances between several of these landmarks were measured. The left condyle, subject to less magnification than the right condyle because it is closer to the film, was more identifiable than the right condyle, which had the highest rating as non-identifiable. Among other landmarks, nasion and point A were the least identifiable, Pog and Me the most. Correlation coefficients for measurements between identifiable landmarks (I-Me) were greater than coefficients for distances involving less identifiable landmarks (S-A). Interestingly, linear measurements were less variable than the identification of corresponding landmarks. These findings corroborate the previous conclusions that clearly identifiable (and the least amount of interpreted) landmarks should be used for proper evaluation of dentofacial relationships. They also suggest, on average, precision in landmark identification is more critical for research purposes than in routine clinical cephalomteric measurements, which serve only as a guide to diagnosis.

The calcium-binding protein S100B (an S100 dimer composed of two S100beta monomers) is proposed to act as a calcium-sensory protein through interactions with a variety of proteins. While the nature of the exact targets for S100B has yet to be defined, random bacteriophage peptide mapping experiments have elucidated a calcium-sensitive "epitope" (TRTK-12) for S100B recognition. In this work, interactions of TRTK-12 with S100B have been shown to be calcium-sensitive. In addition, the interactions are enhanced by zinc binding to S100B, resulting in an approximate 5-fold decrease in the TRTK-12/S100B dissociation constant. Moreover, Zn2+ binding alone has little effect. TRTK-12 showed little evidence for binding to another S100 protein, S100A11 or to a peptide derived from the N terminus of S100B, indicating both a level of specificity for TRTK-12 recognition by S100B and that the N-terminal region of S100B is probably not involved in protein-protein interactions. NMR spectroscopy revealed residues most responsive to TRTK-12 binding that could be mapped to the surface of the three-dimensional structure of calcium-saturated S100B, revealing a common region indicative of a binding site.

An environment to support the modeling, analysis, simulation, and development of state transition models, SMOOCHES (State Machines for Object-Oriented Concurrent Hierarchical Engineering Specifications), is presented. SMOOCHES allows the hierarchical construction, analysis, and simulation of state transition models in an object-oriented distributed environment. Statecharts (see Harel 1987b), a powerful mechanism for state transition specification, are fundamental to the development of SMOOCHES. To assist in the specification of hierarchical state transition models for distributed and reactive systems, statecharts are extended by introducing the concept of exit-safe states. SMOOCHES allows the specification of objects in the system with hierarchical state transition models and the derivation of new classes of objects through inheritance. A graphical monitoring system has been developed to represent and simulate the object state life cycles and monitor event generations. The example presented illustrates the modeling and simulation of different state life cycles of an assembly robot.

Fifty-six Angus and 56 Charolais steers were evaluated for the effects of breed, slaughter weight and diet energy density on feedlot and carcass traits. Eight calves of each breed were slaughtered at the start of the experiment. Forty-eight steers of each breed were assigned for slaughter at 86 (light), 100 (middle) or 114% (heavy) of mean mature cow weight (Angus = 476 kg, Charolais = 612 kg). Diets of corn silage, corn and soybean meal were fed ad libitum; the diets contained 12.5% crude protein and either (1) 2.72 or (2) 2.96 Meal metabolizable energy (ME)/kg dry matter. Mean off-test weights were 267, 409, 472 and 5 34 kg for Angus and 270, 516, 602 and 681 kg for Charolais (initial, light, middle and heavy groups, respectively). Average daily gain (ADG) for both breeds decreased (P<.01) as weight increased, but ADG of Angus and Charolais did not differ from each other. Feed conversions (kilograms diet per unit weight gain) for the breeds were similar. Although light Angus had higher (P<.01) quality grades than light Charolais (∼average versus∼low Choice), grades did not differ between needs at other weights. Breeds did not differ in longissimusmuscle fat content at any assigned weight class. Fat thickness increased (P<.01) for both breeds as weight increased and was greater (P<.01) for Angus within each weight class. Although the higher ME diet (2) did not improve ADG or marbling for either breed, Angus fed diet 2 had greater (P<.05) mean fat thickness and lower (P<.05) carcass cutability than Angus fed diet 1. Angus fed either diet had lower (P<.01) cutability than Charolais. Steaks from Angus carcasses had higher (P<.01) average sensory panel flavor and juiciness ratings than did those from Charolais at the light weight, but sensory panel means did not differ at other weights. Low Choice longissimusmuscle fat content (∼4.3%) was attained at shrunk body weights of 368 kg for Angus and 464 kg for Charolais.

Twelve Charolais bulls were ejaculated once weekly (1×) and 10 bulls six times weekly (6×) from puberty to 2 years of age to determine the effect of age and ejaculation frequency on semen characteristics, sperm output and testes growth; 6× weekly sperm output at 2 and 3 years of age was determined for each of the 22 bulls. Significant increases as bulls aged were found in sperm concentration, sperm motility, weekly total sperm and total motile sperm output, scrotal circumference and width (P<.01) and ejaculate volume (P<.05). From 1 to 2 years of age, average weekly sperm output for 6× bulls increased 2.4 times from 14.0 × 109at 53 to 56 weeks to 33.6 × 109at 101 to 104 weeks of age and for 1× bulls increased 2.2 times from 5.0 × 109to 11.2 × 109at the same ages. For 6× as compared to 1× bulls, ejaculate volume was smaller (P<.01) but total sperm and total motile sperm per week were greater (P<.01); differences for sperm motility, sperm concentration and scrotal circumference and width were not significant.Scrotal circumference and width each increased by 32% from puberty (41 ± 1 weeks) to 2 years of age with slightly over three-fourths of the increase occurring between puberty and 65 weeks of age. Scrotal circumference at 1 and 1.5 years of age was correlated .44 and .52 (P<.05) with 6× weekly sperm output at 2 years of age and .62 and .75 (P<.01) with 6× weekly sperm output at 3 years of age. Testes growth rate, based on the percentage increase in scrotal circumference between 1 and 1.5 years of age, was not significantly correlated (.30) with 6× weekly sperm output at 3 years of age. The correlation increased to .61 (P<.01) when testes growth rate during the first 24 weeks after puberty was used. Thus these relationships accounted for up to 56% of the variation in sperm output. These results and other evidence discussed support the postulate that, except for early detection of bulls with a potential for severe testicular underdevelopment, scrotal measurements of young bulls cannot be used to predict subsequent sperm output precisely.

Mandibular length is measured on cephalographs to depict changes during growth and after orthodontic treatment, and is often defined between condylion (Co, most posterior superior point on the condylar outline) and pogonion (Pog, most anterior point on the chin). The aim of this study was to assess the accuracy of identifying condylar anatomy, thus the validity of using Co-Pog to evaluate mandibular growth. The sample included 34 children from a prospective study on the early treatment of distoclusions. Two lateral head films were taken of each child, the first with the mouth closed (MC), the second with the mouth open (MO). Three examiners, two orthodontists (U.H. and K.H.) and a dental radiologist (R.B.), rated the condyle as identifiable, nonidentifiable, and interpreted. The rating was applied to the left (L) and right (R) condyles, or to only one outline (O) when the R and L structures appeared superimposed and were not distinguished separately. Besides Co-Pog, the orthodontists traced sella-nasion (SN) and incisor tip-menton (I-Me) to evaluate variability in measurements that do not include Co. One operator (J.G.) measured all distances. Agreement among the three examiners was best in rating the MO radiographs (50%): 4.1% identifiable, 5.9% nonidentifiable or interpreted; in the MC films, they agreed in 32.3% of the cases, but only one of the ratings was identifiable (2.9%). The highest agreement was in identifying the left condyle on the MO film (35.3%). Intraclass correlation coefficients for CO-Pog ranged from r = 0.73 (L side) to r = 0.92 (O) for one orthodontist, and for the other from r = 0.76 (O) to r = 0.85 (L). Both orthodontists had high correlations for SN and I-Me between MC and MO (0.94 < r < 0.98). The variability between examiners in recognizing condylar anatomy, particularly on radiographs taken with the mouth closed, suggests that the identification of condylar anatomy must be rated in studies of mandibular growth. Researchers measuring mandibular length in investigations of mandibular growth after orthodontic therapy should differentiate between cases where the condyle is readily identified, and those where condylar anatomy is interpreted. (Am J Orthod Dentofac Orthop 1996;107:645-52.)

Several studies have now gone beyond the effects of smoking during pregnancy to examine the effects of involuntary maternal smoke exposure on fetal development. A link has also been indicated between postnatal environmental smoke exposure and long-term respiratory problems in infants.

Physiological responses of plants to ammonium (NH4) versus nitrate (NO3) nutrition can vary considerably. A greenhouse study was conducted to examine the effect of ammonium-nitrogen/nitrate-nitrogen (NH4-N/NO3-N) ratio on dry matter partitioning and radiation use efficiency in corn (Zea mays L.). The hybrid Funks G 4673A was supplied with nutrient solutions that contained 8:1, 1:1, or 1:8 ratios of NH4-N/NO3-N. At each of four harvests, plants were separated into leaf blades, stem + leaf sheaths, and roots. Radiation use efficiency was calculated from these dry matter harvests and measured photosynthetically active radiation. Generally, more dry matter was partitioned to the stem than to leaf tissue when supplied with the 1:8 NH4-N/NO3-N ratio than when supplied with the other N treatments. Corn supplied with 8:1 and 1:1 ratios of NH4-N/NO3-N resulted in radiation use efficiency values for total dry matter that were significantly higher by 39 and 25%, respectively, than that of corn supplied with the 1:8 ratio indicating that Funks G 4673A was more efficient in converting radiation into dry matter when supplied with high proportions of NH4 than when supplied primarily with NO3.

Studies have indicated that, by maintaining relatively high solution culture or soil NH+4/NO‐3ratios during the reproductive growth stage, certain corn (Zea maysL.) genotypes have a higher yield potential. Unfortunately, few data on soil NH+4and NO‐3levels have been reported. A 3‐yr field experiment was conducted in northeastern Kansas in 1987, 1988, and 1989 to evaluate the effects of time and form of applied N on fertilizer band NH+4/NO‐3ratios and on the N nutrition, dry‐matter accumulation, and grain yield of two corn hybrids. Urea, urea‐NH4NO3, urea plus Ca(NO3)2, NH4NO3, and Ca(NO3)2solutions having NH+4/NO‐3ratios of 1:0, 3:1, 1:1, 1:1, and 0:1, respectively, were used at equivalent N rates. The nitrification inhibitors, nitrapyrin [2‐chloro‐6‐(trichloromethyl) pyridine] and dicyandiamide, as well as two‐way and three‐way timing of application schemes were used to maintain N as NH+4. Split applications of ammoniacal N with a nitrification inhibitor were effective in maintaining elevated soil NH+4concentrations from planting through early grain fill. In 1988 only, grain yield was increased slightly (3–9% higher) when corn was fertilized with ammoniacal N compared with NO‐3only. Overall, manipulation of soil NH+4/NO‐3ratios had few effects on corn development or yield.

Fifty-six Angus and 56 Charolais steers were evaluated to determine effects of breed, slaughter weight and dietary energy density on empty body (EB) composition and energetic efficiency and to compare breeds at compositionally similar body weights. Eight calves of each breed were slaughtered at the start of the experiment. Forty-eight steers of each breed were fed diets containing an estimated 2.72 or 2.96 Mcal metabolizable energy (ME)/kg dry matter; the diets were composed of corn silage, corn grain and a protein, vitamin and mineral supplement. The steers were slaughtered at 86 (light), 100 (middle) or 114% (heavy) of breed average mature cow weight (Angus, 476 kg; Charolais, 612 kg). Forty-seven Angus steers completing the feedlot phase had a mean initial age and weight of 300.9 days and 264.8 kg; 43 Charolais steers had a mean initial age and weight of 284.9 days and 275.6 kilograms. Mean EB weights at slaughter were 231.2, 354.7, 418.2 and 485.6 kg for Angus (in the initial, light, middle and heavy slaughter groups, respectively; P<.01) and 239.8, 457.9, 540.1 and 617.7 kg for Charolais. EB fat content increased (P<.01) within each breed with increased slaughter weight. Light, middle and heavy Angus steers deposited 41.0, 44.4 and 43.8%, respectively, of their EB gain as fat. Despite slaughter at heavier body weights and at percentages of mature dam weight comparable to those for Angus, corresponding Charolais groups deposited 36.3, 37.3 and 39.2%, respectively, of their EB gain as fat (breed differences, P<.01). The increase in dietary energy from diet 1 to diet 2 resulted in greater (P<.01) EB fat deposition for Angus, but not for Charolais. For Angus fed diet 1, EB gain from 231.2 to 354.7 kg (39.1% fat) was compositionally similar to Charolais EB gain from 239.8 to 617.7 kg (39.2% fat). Despite these differences in rate of fattening, final EB composition for Angus and Charolais slaughter groups differed (P<.01) only at the middle weight. Comparable EB fat content (30%) was attained by Angus steers at 455 kg (diet 1) and 431 kg (diet 2) shrunk body weight and by Charolais steers at 619 kg (diets 1 and 2) shrunk body weight.

Data were collected on 32 purebred Angus and 32 Charolais (minimum 88% purebred) steers. Eight calves of each breed were slaughtered to provide initial carcass data. The remaining steers were randomly assigned to six slaughter groups in a 2 × 3 factorial design to evaluate breed and slaughter weight effects on retail lean, bone and fat yield and distribution. A diet composed of corn silage, cracked corn and soybean meal with an estimated DE content of 3.64 Mcal/kg DM was used. Angus were slaughtered at 267,408,476 and 542 kg and Charolais at 270, 527, 612 or 697 kg (initial, light, middle or heavy slaughter groups) corresponding to 86, 100 and 114% of the mean cow weight of the respective breed. Means for weight per day of age, daily gain and marbling scores were similar for Angus and Charolais steers of the same slaughter weight group. Wholesale and retail lean weights were generally heavier for Charolais steers and increased between slaughter weight groups for both breeds (P<.05 or P<.01). With the exception of bottom sirloin, round tip and round lean trim percentages, retail cut distribution (not presented) was not significantly affected by breed or slaughter weight within breed. Percentage retail lean was the same for Angus and Charolais final groups. However, estimated and actual RLRC (round, loin, rib and chuck) retail cuts per day were greater (P<.01) for Charolais steers only in the initial and light-weight slaughter groups. Total fat percentage was greater (P<.05) for Angus, but the Charolais advantage of less fat deposition was at least partly offset by Charolais higher (P<.05) bone content.These results suggest that neither breed nor slaughter weight had marked effects on relative distribution of retail lean, fat or bone throughout the animal's body. In addition, although significant breed differences were noted for fat and bone content, differences in growth rate and retail lean were relatively minor when cattle were slaughtered at similar percentages of the corresponding breed average mature weight.

Building software systems that are easier to use implies addressing the issue of increasing complexities in managing processes and communication between processes. In order to manage complexity, it is very important to have tools, notation, and methodologies which support the designer's work during design resolution. This paper introduces Extended Statecharts as a comprehensive modelling mechanism for high-level systems design. Extended Statecharts allow for the implicit representation of declarable, problem-specific system soft failures, thereby allowing for failure related information to be incorporated into the highlevel system design. Temporal logic is used for verification of important design properties. An example of an assembly process is used to illustrate the capabilities of Extended Statecharts.

Multilamellar liposomal amphotericin B (L-AmB) was generally less active in vitro against yeast strains than was amphotericin B-deoxycholate or free amphotericin B, although continual agitation of the broth disproportionately increased the activity of L-AmB. Time-kill studies also demonstrated a slower onset of action of L-AmB and supported the hypothesis that liposomes may act as reservoirs for free amphotericin B, which is the active moiety.

Alzheimer's-afflicted neurons contain phosphorylated forms of tau that are not present in healthy adults, these can be recognized with great specificity by monoclonal antibodies such as paired helical filament-1 (PHF-1) [Greenberg S. G. and Davies P. (1990)Proc. natn. Acad. Sci. U.S.A.87, 5827–5831; Greenberg S. G.et al. (1992)J. biol. Chem.267, 564–569]. The PHF-1 phospho-tau epitope is also present in immature neurons undergoing axodendritic differentiation [Pope W. B.et al. (1993)Expl Neurol.120, 106–113]. Analogous to its presence in immature neurons, we report here that the PHF-1 tau epitope spontaneously occurs in the human neuroblastoma cell line SHSY5Y, where its level can be regulated by differentiation and by molecules found in the extracellular matrix. Confocal immunofluorescence studies showed PHF-1 epitope to be constitutively expressed in the somatic cytoplasm as well as in short neurites typical of undifferentiated SHSY5Y cells. Induction of differentiation with retinoic acid produced cells with a neuronal morphology and a redistribution of the expression of PHF-1 tau in the long neurites. Protracted exposure to retinoic acid decreased the levels of PHF-1 immunofluorescence without a loss of neurites, similar to the developmental down-regulation seenin situ. The effects of retinoic acid on PHF-1 immunofluorescence were modifiable by fibronectin, which can be released by some neuroblastoma cell lines [Ciccarone V.et al. (1989)Cancer Res.49, 219–225; Yoshihara T.et al. (1992)Int. J. Cancer51, 620–626.]. Exogenous human fibronectin caused a marked up-regulation of PHF-1 immunofluorescence. Quantitative analysis of 15 multicellular areas, from six different cultures, per experimental condition showed a 16-fold increase compared to untreated controls. Up-regulation by fibronectin was also evident in undifferentiated cells. Cell counts indicated no proliferative effects of the fibronectin under the conditions used. Laminin also caused an increase of PHF-1 tau in retinoic acid-treated cells. Data obtained from immunoblots verified the results observed with immunofluorescence. The data show that the PHF-1 tau epitope is spontaneously expressed by non-degenerating human neuroblastoma cells, down-regulated by cellular differentiation, induced by retinoic acid and up-regulated by the extracellular matrix components fibronectin and laminin. One explanation of the data is that fibronectin maintains a population of SHSY5Y cells in a biochemical state of differentiation in which PHF-1 tau is expressed. This effect occurs depsite the presence of morphological changes accompanying long-term retinoic acid-induced differentiation.

A beta is a 39-43-amino acid peptide that accumulates as extracellular aggregates in Alzheimer's disease-afflicted brain tissue. Contact between these aggregates and neurons is potentially pathogenic, although little is known about the cellular transduction mechanisms. We have investigated the impact of A beta aggregates on the neuronal control of protein tyrosine phosphorylation, which underlies signal transduction for multiple families of growth factor and adhesion receptors. Added to cultures of rat and human nerve cell lines, A beta aggregates evoked a non-desensitizing increase (1.3-3.6-fold) in tyrosine phosphorylation in a band at 118 kDa. The 118-kDa protein was determined by immunoprecipitation to be pp125FAK, not previously documented in cells of neuronal lineage. Immunoblots with anti-focal adhesion kinase (FAK) showed that A beta aggregates had no effect on FAK protein levels. The increase in FAK tyrosine phosphorylation occurred at doses of A beta aggregates that evoked lactate dehydrogenase release; evoked tyrosine phosphorylation preceded the first detectable lactate dehydrogenase release by 4 h. Like degeneration, the FAK response was dependent on A beta aggregation and neuronal differentiation. Since tyrosine phosphorylation of FAK is essential to its activity as a transduction component of integrin-, peptide-, and lysophosphatidic acid-mediated signaling, the data establish a link between A beta aggregates and signal transduction pathways implicated in diverse cell functions including neurite outgrowth, control of the cell cycle, and apoptosis.

Twenty-two purebred Charolais bulls were fed concentrate ad libitumfrom weaning through 550 days of age. Puberty, defined as the age at which the first ejaculate containing a minimum of 50 × 106sperm with at least 10% showing progressive motility was collected by artificial vagina, was attained at a mean age of 41 ± 1 weeks and a mean body weight of 396 ± 13 kilograms. One bull was removed from experiment after 365 days of age because of chronic bloat, three bulls lacked data for feed consumption and six bulls had not attained 2 years of age when the data were analyzed. Mean body weights of 356 ± 10, 520 ± 11, 744 ± 14 and 859 ± 20 kg were recorded at 265, 365, 550 days and 2 years of age, respectively. Average daily gain (ADG) and feed efficiency during a 285-day test (265 to 550 days of age) averaged 1.35 ± .03 and 8.09 ± .16 kilograms.

Twenty-seven Charolais weanling purebred bulls, fed concentrate ad libitum, were used to study puberal characteristics and early growth. Three calves were removed from the experiment for inability to protrude the penis and serve the artificial vagina.For the 24 bulls the average age at collection with artificial vagina of the first sperm and first motile sperm was 38 ± 1 and 39 ± 1 weeks, respectively. The first ejaculate meeting the minimum puberal criteria was obtained at a mean age of 41 ± 1 weeks. Body weight at puberty averaged 400 ± 13 kilograms. The ranges in age and body weight were 33 to 53 weeks and 266 to 499 kilograms. Semen characteristics and freezability of the first ejaculate were highly variable. First ejaculates for seven of the 24 bulls, however, satisfactorily withstood freezing and 3 weeks of storage in liquid nitrogen.Body weight at 365 days of age averaged 520 ± 10 kg (range 430 to 615 kg).

Previously, it has been shown that incorporation of the membrane channel-forming polyene antibiotic, amphotericin B (AMB), into liposomes composed of dimyristoyl phosphatidylcholine/dimyristoyl phosphatidylglycerol (7:3 ratio) results in reduced drug toxicity to animals with full retention of therapeutic activity against systemic fungal infections. In this report we explore the cellular and biochemical bases of the enhanced therapeutic index of liposomal amphotericin B (L-AMB). AMB and L-AMB are equally potent and both promptly induce rapid cation efflux from Candida albicans cells. By contrast, AMB, but not L-AMB, induces cation efflux and cell lysis in mammalian erythrocytes, demonstrating the selectivity of L-AMB at the cellular level. The characteristics of the lipid of the erythrocyte membrane seem to be the most important determinant of cellular sensitivity, since AMB, but not L-AMB, induces cation release from large unilamellar liposomes composed of red cell membrane lipids, thus paralleling the observations on intact cells. The ability of L-AMB to induce cation release and cause toxicity to erythrocytes, however, can be modulated by changing the lipid composition of the liposome carrier. Thus, AMB-containing liposomes composed of phospholipids with saturated acyl chains are nontoxic, whereas AMB liposomes composed of phospholipids containing unsaturated acyl chains are almost as toxic as AMB itself. The acyl chain composition rather than the head group composition seems most important, although substitution of anionic phosphatidylglycerols for phosphatidylcholines contributes somewhat to the protective effect. Analysis of several types of liposomes containing AMB at concentrations up to 5 mol %, using electron paramagnetic resonance and freeze fracture electron microscopy, shows that the drug is incorporated in the lipid bilayer but produces only modest disruptive effects on bilayer structure. Current results are interpreted in terms of a selective transfer of AMB from "donor" liposomes to "target" cell membranes. The transfer process probably occurs by diffusion of AMB through the solvent but is regulated by the physical properties of both donor and target membranes.

This paper presents a design of an assembly sequence planner based on a “plan reuse” philosophy. Most of assembly planning research in the past has attempted to completely plan each problem from scratch. This research shows that stored cases of basic assembly configurations can be applied to a given assembly problem. It is observed that the number of such basic assembly configurations is quite small. The planner divides the assembly into a number of constituent configurations, which are called “loops”. These act as subgoals in its search for solutions. Plans retrieved for all subgoals are fused into a set of plans that are consistent with the constraints implied by each plan. Application specific constraints on the assembly are explicitly handled in the second phase of planning. Mechanisms for assembly representation and implementation details of the planner are also presented.

When necessity arises that makes a wide resection of the bladder peremptory, a large number of patients become solicitous as to what the function of the bladder will be after part of it has been removed. This solicitude arises so often that it is a striking feature, and it is because the urologist is assailed by this question that it has occurred to us that the function of the small bladder, or rather the regeneration of the bladder following resection, is important enough to merit consideration.The two lesions which most frequently require resections are carcinoma and elusive ulcer. If the lesions are treated by resection, it is imperative that the resection be very wide, and as a result a very small bladder is often left. This induces the frequent query on the part of the patient as to the ultimate outcome, from the point of view of the proper

This paper reviews investigations of the E-Sinteraction variable in verbal conditioning. The research is viewed in terms of the constructs of interpersonal attraction and interpersonal influence and is categorized under the headings: (a) experiments in which Es with different physical and personality characteristics are used; (b) experiments in which S's attraction to Eis manipulated by S's interaction with him (resultant interpersonal attraction); (c) experiments in which S's attraction to Eis manipulated by matching Es with Ss on the basis of psychological test scores; (d) experiments in which S's attraction to Eis manipulated by having a collaborator give Sinformation about E(induced interpersonal attraction). Major findings are summarized and suggestions for future research mentioned.

• We saw four unrelated cases of human orf infection over a 3-month period. Each patient had a clear-cut history of contact with sheep and developed a characteristic painful pustular lesion on the hand. There were no significant systemic symptoms. Examination of an aspirate by electron microscopy confirmed the diagnosis. The lesions resolved spontaneously within 6 weeks. Human orf infection occurs in North America, and although seldom reported, it should be considered in the diagnosis of cutaneous lesions in patients who have exposure to animals associated with it.(Arch Dermatol. 1990;126:356-358)