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Summary: Volatile short-chain fatty acids such as butyric and acetic acid have been supplemented in poultry rations as a feed ingredient and nutritive supplement. A novel Clostridium fermentation solubles broth (MiruTyton), containing short-chain fatty acids, minerals, and amino acids, was supplemented in a standard corn/soybean meal–based ration at a rate of 750, 1,500, 3,000, and 6,000 mg/kg to achieve approximately 277, 554, 1,108, and 2,216 mg/kg of ammonium butyrate in the diet. After 6 wk, supplementation at all levels did not cause significant changes in the blood parameters or any live performance metric of mixed-sex Cobb-500 broilers (N = 1,920). In addition, administering 6,000 mg/kg of MiruTyton caused no significant lesions in any of the tissue examined except for an increase (P

Background and aims Organic matter is often used as an amendment to attempt restoration of degraded soils to improve tree establishment and growth. One key aim is to increase plant available water in the soil profile. The texture of the soil, the type of organic amendment (e.g. compost or biochar), and the native environment of the tree (mesic or xeric) will impact how successful restoration efforts are. We aimed to determine whether compost and biochar amendments, either individually or in combination, would improve plant available water (PAW) in both clay and sand soils. We then aimed to measure whether changes in PAW would translate into increased water use and plant growth of both mesic (Corymbia maculata) or xeric (Eucalyptus torquata) tree species under well-watered (WW) or water deficit (WD) conditions. Methods Clay and sand soils were amended with compost, biochar or a compost and biochar mix, whilst unamended soils acted as controls. Soil moisture characteristics of the soil mixes were determined with samples in the laboratory. Fifteen replicate pots (6 l) of each soil treatment were then planted with either mesic and xeric tree species. All pots and trees were subjected to either a WW or WD irrigation regime for 7 weeks. WD irrigation was a set percentage of the daily WW evapotranspiration (ET). ET was calculated as total pot mass one hour after irrigation (to allow for drainage) minus the total pre-dawn pot mass of the subsequent day. The tree biomass, biomass partitioning, ET, and tree water status were measured throughout the experiment to understand growth and stress responses. Key results The xeric tree species (E. torquata) grown in sand soil had a significant increase in growth with all three OM amendments but did not when grown in clay soil. In contrast, we found no significant growth response for the mesic tree species (C. maculata) when grown in either clay or sand amended with any OM treatment. The ET of the xeric tree species was greater for all the OM amended soils for both WW and WD plants in the sand soil. Conclusions This study shows that OM amendments may improve the soil water properties of sand-based soils which in turn can increase the growth of xeric tree species. However, more expensive organic amendments may not be necessary, nor mixing of OM types, as we found no tree growth differences amongst the three different OM treatments.

A quenching agent is commonly added to chlorinated, reclaimed water during sample collection to prevent chlorine-mediated die-off of viable microbiota. However, the effect of quenching on downstream 16S rRNA-based bacterial community analyses is unclear. We conducted a side-by-side comparison of 16S rRNA sequencing data from reclaimed water samples quenched with sodium thiosulfate and non-quenched samples. Our data showed that 16 S rRNA processing and sequencing methods, and resulting bacterial profiles, were not negatively impacted by quenching.

The microbial quality of irrigation water has increasingly become a concern as a source of contamination for fruits and vegetables. Non-traditional sources of water are being used by more and more growers in smaller, highly diversified farms in the Mid-Atlantic region of the U.S. Shiga-toxigenic E. coli (STEC) have been responsible for several outbreaks of infections associated with the consumption of leafy greens. Our study evaluated the prevalence of the “big seven” STEC serogroups and the associated enterohemorrhagic E. coli (EHEC) virulence factors (VF) genes in conventional and nontraditional irrigation waters in the Mid-Atlantic region of the U.S. Water samples (n = 510) from 170 sampling events were collected from eight untreated surface water sites, two wastewater reclamation facilities, and one vegetable processing plant, over a 12-month period. Ten liters of water were filtered through Modified Moore swabs (MMS); swabs were then enriched into Universal Pre-enrichment Broth (UPB), followed by enrichment into non-O157 STEC R&F broth and isolation on R & F non-O157 STEC chromogenic plating medium. Isolates (n = 2489) from enriched MMS from water samples were screened for frequently reported STEC serogroups that cause foodborne illness: O26, O45, O103, O111, O121, O145, and O157, along with VF genes stx1, stx2, eae, and ehxA. Through this screening process, STEC isolates were found in 2.35% (12/510) of water samples, while 9.0% (46/510) contained an atypical enteropathogenic E. coli (aEPEC) isolate. The eae gene (n = 88 isolates) was the most frequently detected EHEC VF of the isolates screened. The majority of STEC isolates (stx1 or stx2) genes mainly came from either a pond or reclamation pond water site on two specific dates, potentially indicating that these isolates were not spatially or temporally distributed among the sampling sites. STEC isolates at reclaimed water sites may have been introduced after wastewater treatment. None of the isolates containing eae were determined to be Escherichia albertii. Our work showed that STEC prevalence in Mid-Atlantic untreated surface waters over a 12-month period was lower than the prevalence of atypical EPEC.

Large trees are often seen as a means of offsetting negative consequences of growing urban densification. To increase the tree canopy cover of dense urban landscapes, developers, planners and urban tree managers are often forced to plant into damaged and compacted sites. Compacted urban soils can hinder the establishment and growth of deep rooted, woody plants by: 1) impeding root exploration and development which is critical for water and nutrient acquisition; 2) reducing infiltration of water into the soil and the availability of water to plants; and 3) reducing gas exchange and the balance between anaerobic and aerobic conditions. At three sites in Melbourne, Australia with compacted and damaged soils, we established four soil remediation treatments: 1 & 2) tillage to 0.25 m with and without 50% (v/v) municipal green waste compost (MGWC) additions, and 3 & 4) tillage to 0.5 m with and without 50% MGWC addition, plus a non-remediated control. Each treatment was replicated (n = 3), and one Corymbia maculata (spotted gum) tree was planted into the centre of each 2 × 2 m treatment plot (n = 15), at all three sites (n = 45). Bulk density and field-saturated hydraulic conductivity were improved by tillage, at least in the short-term. The use of MGWC may maintain these changes for longer. Depending on site soil conditions tree growth may be improved by tillage alone. At one site, we found that additions of MGWC lead to nitrogen immobilisation due to site soil conditions. At another site, deep tillage (with or without MGWC) led to significantly improved tree growth. Compacted and degraded urban soils may be improved through simple tillage and/or organic amendment strategies for the successful establishment of deep rooted woody plants. However, site soil conditions will dictate whether the addition of MGWC is beneficial or not, as one site showed no positive response to any tillage or MGWC. This research has examined a technique that can be used by landscape managers to improve soil physical characteristics and, in certain circumstances, can improve deep-rooted woody plant establishment and growth in challenging compacted urban soil conditions.

The way a street tree is able to modify the local microclimate on pedestrian walkways may vary according to tree species according to key canopy and leaf characteristics, such as leaf angle, leaf size, canopy architecture or simply canopy density. Three similar north-south orientated streets, with three different tree species possessing different canopy and leaf characteristics were studied in summer 2014. Microclimatic parameters were measured on pedestrian walkways below and away from tree canopies between 06:00 and 20:00 on three cloudless days. Physiological Equivalent Temperature (PET) was estimated to indicate pedestrian thermal comfort. Microclimate conditions were measured below and away from trees at solar noon for a wide range of trees with different Plant Area Index (PAI) as determined using full-frame photography. In streets with Ulmus procera and Platanus x acerifolia trees, the microclimatic benefits were significantly greater than the street with Eucalyptus scoparia trees, however no significant differences in the estimated PET. Microclimate benefit increased with increasing PAI for all three tree species, however no significant difference in under-canopy microclimate amongst tree species when the PAI was similar. It appears that differences in PAI are paramount in determining the microclimatic and PET benefits. Obviously, certain tree species have a limit of the PAI they can achieve, and that should be considered when selecting or comparing tree species for shading and cooling benefits. This study assists urban planners and landscape professionals in selecting street tree species for cooling benefits based on the expected or managed tree canopy area.

Agricultural drainage ditches represent a major source of nutrient pollution. Shifts in nitrogen source and use of animal manures have changed the bacterial composition both in species of bacteria and their abundance in agricultural ditches. This change affects how nitrogen is being cycled and potentially the final forms of available nutrients. In particular, animal manures often have bacteria such as Escherichia coli present, increasing the abundance of a bacterial species in ditches. Research has shown that the effect of different nitrogen sources is to change bacterial community composition (class, family). How this influences the role of an individual bacterial species is poorly understood. Thus, our question was how individual species would respond to different sources of nitrogen. We used Aeromonas hydrophila, Bacillus thuringiensis, Escherichia coli and Pseudomonas aeruginosa that are common in agricultural ditches and exposed them to different concentrations of nitrogen in cultures of 1 × 100 and 1 × 10−1 dilutions from a stock solution of bacteria. Nitrogen sources were ammonium chloride, sodium nitrate and urea. The results showed A. hydrophila and E. coli have strong similarities particularly with nitrate-N and urea-N utilization and the response was often correlated with the amount of nutrient added. P. aeruginosa while similar did not show any strong correlation with amount of nutrient added. B. thuringiensis was different from the other three bacteria in utilization or production. Research has provided insight into the role of some bacteria in nitrogen cycling and may be valuable in the future to developing management strategies to reduce nutrients., Agriculture; Microbiology; Agricultural soil science; Agricultural water management; Bacteria, Nitrogen, Utilization, Ammonium, Nitrate, Urea.

Soil compaction can be a major impediment to tree growth as it damages soil physical and biological properties and reduces plant available water. This may result in trees that are more vulnerable to seasonal water stress. Improving soil physical and biological properties by increasing soil organic matter content may lead to improved tree establishment. Organic matter (OM), in the form of municipal green waste compost (MGWC) or biochar was incorporated into compacted urban soils at two sites. We established six soil treatments: 1) unamended, 2) tillage only, 3) tillage with MGWC (20% v/v), 4) tillage with biochar (10% v/v), 5) tillage with MGWC + biochar (10% & 5% v/v - low), and 6) tillage with MGWC + biochar (20% & 10% v/v - high) (one site only). The treatments were established to a depth of 0.5 m in 2 × 2 m plots. One Corymbia maculata sapling was planted into each plot. Bulk density, hydraulic conductivity, stem diameter growth and tree water status were measured during tree establishment. At the end of the 30-month experiment, development of water stable aggregates, the rate of microbiological decomposition of OM, and tree size (diameter at breast height; DBH, and canopy growth index) were measured. All OM amended treatments improved soil physical and biological properties. There were no significant differences among the OM treatments. At the end of the experiment, tree DBH and canopy growth index were greater in the OM treatments than tillage only and unamended. As such, we recommend using local and sustainable forms of OM to improve soils and assist tree establishment in challenging sites where soil water is limited, or evapotranspiration demand is high.

Dissolved organic matter (DOM) provides nutrients and energy subsidies for harmful algal blooms in Maryland's Coastal Bays (MCBs, USA). The composition, sources and dynamics of DOM in MCBs are not well known. In this study, dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) were monitored monthly over a period of one year (July 2011 to June 2012) at 13 stations in the MCBs. Absorption and fluorescence spectroscopy were used to characterize DOM composition and track terrestrial inputs versus aquatic sources of DOM. Results show that DOC and TDN concentrations in the MCBs (187–501 μM and 19.4–40.6 μM) were comparable to eutrophic coastal waters in the United States but much higher than the mid-Atlantic Bight. This suggests that the MCBs are a DOM source for the coastal ocean. Spatially, nearshore sites had relatively higher DOC and TDN concentrations and terrestrially-derived aromatic DOM (indicated by high humification index) than the bays that were directly connected to the Atlantic Ocean. Seasonally, DOC from the main body of the MCBs (Chincoteague and Assawoman Bays) displayed a pronounced seasonal pattern with the highest values occurring in summer. Protein-like DOM from algal/bacterial inputs (indicated by high biological freshness index or fluorescence index) was also highest in summer but then decreased gradually until April. DOC concentrations at the nearshore site were highest in later spring, probably due to terrestrial inputs. Conversely, TDN concentrations in smaller bays with faster flushing rates (Newport, Sinepuxent and Isle of Wight Bays) were highest in April, probably due to watershed nitrogen inputs. This spring TDN peak was not apparent in the main body of the MCBs, which have longer flushing times (indicating stronger biological nitrogen uptake). This study suggests that DOM in eutrophic, shallow coastal bays such as the MCBs consists of a large fraction of protein-like components from local algal/microbial sources during summer. This enhanced primary productivity is likely fueled by watershed nitrogen inputs from agricultural and urban land use during spring. Further insights regarding spatiotemporal variations and controls of DOM abundance, composition and sources in the MCBs can be helpful in guiding and prioritizing coastal restoration efforts for reducing eutrophication and water quality degradation.

The primary objective of this study was to evaluate changes in student confidence resulting from completion of the American Pharmacists Association (APhA) certification course, an immunization-based simulation, and practical experience in influenza immunization clinics during an Introductory Pharmacy Practice Experience (IPPE). Secondary objectives included evaluation of influences on student confidence such as campus location, prior APhA certification, and prior experience in preparing injectable medications. Methods An eight-question survey was administered to third-year pharmacy students in Fall 2011 to measure confidence in immunization skills and knowledge at four time points; before APhA certification, after APhA certification, after participation in the simulation, and after 12 hours of practical experience in influenza-based immunization clinics. The simulation consisted of case-based scenarios and a skill assessment. Results Upon IPPE completion, at least 86.6% of students reported either confidence or extreme confidence for all survey items. Student confidence increased significantly between time points and from baseline to IPPE completion. Students certified prior to Fall 2011 were significantly less confident at baseline in some of the legal issues and response to anaphylactic reactions; however, this difference became non-significant after completion of the simulation. Conclusions All three training modules are important in preparing students for immunization delivery in their future practice. Schools of pharmacy should consider increasing opportunities for development of student confidence in this area. The lack of initial confidence regarding legal requirements in students certified prior to Fall 2011 may indicate the need for recertification or mandatory immunization-based continuing professional development for immunizing pharmacists.

Organoamine–inorganic hybrid adsorbent materials were synthesized by covalent immobilization of alkylaminotrimethoxysilanes and polyethyleneiminetrimethoxysilane onto fumed silica (nanosilica). The obtained silica–organic hybrid materials were characterized by thermogravimetry and diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) confirming the successful grafting of the amine derivatives to silica and their surface area measured using Brunauer–Emmett–Teller method (BET). The influence of reaction conditions on the graft density of organoamines was investigated and it was found that the saturation of the silane coupling agents with carbon dioxide prior to surface modification resulted in higher graft densities. Carbon dioxide uptake of the obtained hybrid materials were determined by thermogravimetric analysis at room temperature as well as higher temperatures resulting in CO2 adsorption capacities from 32.4 to 69.7 mg g−1 adsorbent.

Objective Medical errors are a nearly universal experience for physicians. An error that harms a patient is one of the most difficult experiences that physicians face. Difficult experiences can result in growth. This study investigates how physicians coped positively with having made a serious mistake. This paper describes common elements identified in how physicians coped positively with these difficult circumstances, and the positive ways in which they learned and changed. Methods Physicians were recruited nationally through advertisement and word of mouth. Researchers conducted in-depth interviews with 61 physicians who had made a serious medical error. Verbatim transcripts were analyzed using a grounded theory approach and constant comparative analysis methodology. Results Our analysis identified five major elements in the process of coping positively with the experience of a serious medical error. These elements included acceptance, stepping in, integration, new narrative and wisdom. Subthemes further detail the content within each element. Conclusion This study provides evidence that the experience of coping with a serious mistake can be formative in a positive way for physicians and provides a “roadmap” for growth through this experience. Practice implications The profession must now seek ways to foster the development of wisdom out of these difficult experiences.

The purpose of the current study was to determine the obesogenic practices in all-day child-care centers caring for preschool-aged children. This study used a cross-sectional, self-reported survey mailed to centers across Oklahoma (n=314). Frequency of responses and χ 2 were calculated comparing region and star rating. Items where the majority of centers frequently report best practices include: daily fruits served (76%), daily nonfried vegetables served (71%), rarely/never served sugary drinks (92%), rarely/never used food to encourage good behaviors (88%), staff join children at table most of the time (81%), staff rarely eat different foods in view of children (69%), visible self-serve or request availability of water (93%), regular informal communication about healthy eating (86%), opportunities for outdoor play (95%), not withholding activity for punishment (91%), accessible play equipment (59% to 80% for different types of equipment), and minimization of extended sitting time (78%). Practices where centers can improve include increasing variety of vegetables (18%), reducing frequency of high-fat meats served (74% serve more than once per week), increasing high-fiber and whole-grain foods (35% offer daily), serving style of "seconds" (28% help kids determine whether they are still hungry), nonfood holiday celebrations (44% use nonfood treats), having toys and books that encourage healthy eating (27%) and physical activity (25%) in all rooms in the center, a standard nutrition (21%) and physical education (50%) curriculum, and following a written physical activity policy (43%). Practitioners can use these data to develop benchmarks and interventions, as this was the first study to assess statewide obesogenic practices in child care.

Normal circadian variations in vasoactive intestinal polypeptide, somatostatin, cholecystokinin and pancreatic polypeptide were measured to determine if these alter with aging and to identify gastrointestinal regulatory hormones that might control the dramatic diurnal variation in the gastric cytoprotective trefoil protein TFF2. Plasma pancreatic polypeptide concentrations showed a marked diurnal rhythm (p < 0.0001). Basal and postprandial pancreatic polypeptide concentrations increased with age (p < 0.01). The timing of the diurnal rhythm was consistent with pancreatic polypeptide inhibiting TFF2 secretion and there was a negative association between pancreatic polypeptide and TFF2 concentrations (p < 0.002). The much higher pancreatic polypeptide concentrations in older people will induce increased satiety that may contribute to 'anorexia of ageing'. These results identify potential therapies for treatment of gastric mucosal morbidity and age-associated loss of appetite.

Background/Purpose Although the pathogenesis of necrotizing enterocolitis (NEC) is not completely defined, ischemia appears to be one of the most important causative factors. Trefoil factor family peptide 3 (TFF3) is a peptide normally expressed in the small bowel and colon and is involved in the maintenance and repair of mucosal integrity. The authors hypothesized that monomeric (TFF3 Ser 57 ) and dimeric (TFF3 Cys 57 ) recombinant TFF3 may prevent the development and accelerate healing of intestinal ischemia-reperfusion injury in weanling rats. Methods Intestinal injury was induced in 18-day-old rats by occlusion of the superior mesenteric vessels for 60 minutes. To examine the protective effect, rats were given 3 μg/g of TFF3 Ser 57 or TFF3 Cys 57 by subcutaneous or enteral administration 30 minutes before the vascular occlusion. To examine the healing effect, rats were given 3 μg/g of TFF3 Ser 57 or TFF3 Cys 57 by subcutaneous or enteral administration 60 minutes after the beginning of reperfusion. Samples from small bowel and colon were collected for morphometric analysis after 3 hours of reperfusion. Mucosal damage was assessed by the Chiu score. Results Both forms of TFF3 reduced the amount of damage when administered before the ischemia. Administration of TFF3 Ser 57 and TFF3 Cys 57 after the beginning of reperfusion significantly increased the villous height and decreased the Chiu score in the small intestine and colon. Conclusions TFF3 Ser 57 monomer and TFF3 Cys 57 dimer prevent the development and promote healing of ischemia-reperfusion injury in weanling rats. There are no differences between the routes of administration of TFF3.

The expression of TFF2 in breast cancer cells and the effect of recombinant TFF2 on breast cancer cell migration were assessed. TFF2 expression was detected by PCR in estrogen receptor-negative and at lower levels in estrogen receptor-positive breast cancer cells. TFF2 expression was detected in nine out of 10 primary breast tumors but its expression was not related to that of the estrogen receptor. Focal expression was observed in normal and tumor cells by immunohistochemistry. TFF2 stimulated the migration of estrogen-responsive MCF-7 and non-responsive MDA-MB231 cells. We conclude that TFF2 is expressed in normal and malignant breast epithelial cells and that it stimulates the migration of breast cancer cells.

Statement of Problem. Limiting abutment-to-implant hexagonal discrepancies and rotational movement of the abutment around the implant to less than 5 degrees would result in a more stable screw joint. However, the exact relationship after abutment screw tightening is unknown, as is the effect of a counter-torque device in limiting abutment movement during screw tightening. Purpose. This study examined the orientation of the abutment hexagon to the implant hexagon after tightening of the abutment screw for several abutment systems with and without the use of a counter-torque device. Material and Methods. Thirty conical self-tapping implants (3.75 × 10.0 mm) and 10 wide-platform Branemark System implants (5.0 × 10.0 mm), along with 10 abutment specimens from the CeraOne, Estheticone, Procera, and AuraAdapt systems, were selected for this investigation. The implants were placed in a holding device prior to tightening of the abutments. When the tightening torque recommended for each abutment system was reached with the use of a torque controller, each implant abutment specimen was removed from the holding device and embedded in a hard resin medium. The specimens were sectioned in a horizontal direction at the level of the hexagons and cleansed of debris prior to examination. The hexagon orientations were assessed as the degree and direction of rotation of the abutment hexagon around the implant hexagon. Results. The range of the maximum degrees of rotation for all 4 abutment groups tightened with or without the counter-torque device was slightly more than 3.53 degrees. The absolute degrees of rotation for all 4 abutment groups were less than 1.50 degrees with or without the use of the counter-torque device. Conclusion. The hexagon-to-hexagon orientation measured as rotational fit on all abutment systems was below the 5 degrees suggested as optimal for screw joint stability. The absolute degrees of rotation for all 4 abutment groups were less than 1.50 degrees regardless of whether the counter-torque device was used. (J Prosthet Dent 2002;87:74-9.)

We report on a measurement of the ratio of the differential cross sections for W and Z boson production as a function of transverse momentum in proton-antiproton collisions at sqrt(s) = 1.8 TeV. This measurement uses data recorded by the D0 detector at the Fermilab Tevatron in 1994-1995. It represents the first investigation of a proposal that ratios between W and Z observables can be calculated reliably using perturbative QCD, even when the individual observables are not. Using the ratio of differential cross sections reduces both experimental and theoretical uncertainties, and can therefore provide smaller overall uncertainties in the measured mass and width of the W boson than current methods used at hadron colliders., Comment: 10 pages, 2 figures, to be published in Physics Letters B

Breast cancer screening is important for the early detection of breast cancer. Tumors that become symptomatic in the screening interval are known as interval cancers but the reasons for their rapid progression are unknown. Estrogen receptor expression is lower in interval cancers suggesting that they may have reduced hormonal responsiveness. To investigate this hypothesis we have measured the expression of the estrogen receptor and three estrogen-responsive genes (cathepsin D, progesterone receptor, and TFF1) in screen-detected and interval breast cancers. The expression of the protease cathepsin D was not associated with estrogen receptor in either group of tumor. Progesterone receptor expression was highly correlated with that of the estrogen receptor in both groups of tumors but it was not expressed at significantly different levels in the two groups of tumors. Expression of TFF1, a cellular motogen, was correlated with estrogen receptor in screen-detected but not interval cancers and was expressed at markedly higher levels in interval breast tumors, the group that expresses lower levels of estrogen receptor. Interval cancers are characterized by high levels of expression of TFF1 and/or Ki67 suggesting that cell migration and cell division play important roles in the rapid progression of interval cancers. The observation that TFF1 expression in interval cancers tends to be estrogen-independent and that interval cancers have reduced estrogen receptor expression suggests they may have a reduced response to hormone therapy.

We present measurements of the b-bbar production cross section and angular correlations using the D0 detector at the Fermilab Tevatron p-pbar Collider operating at sqrt(s) = 1.8 TeV. The b quark production cross section for |y(b)| 6 GeV/c is extracted from single muon and dimuon data samples. The results agree in shape with the next-to-leading order QCD calculation of heavy flavor production but are greater than the central values of these predictions. The angular correlations between b and bbar quarks, measured from the azimuthal opening angle between their decay muons, also agree in shape with the next-to-leading order QCD prediction.

Statement of problem. Little is known about the condition of the abutment-screw joint before loading, after the development of the preload. Purpose. This study examined the tightening force transmitted to the implant with and without the use of a counter-torque device during the tightening of the abutment screw. Materials and methods. Forty Branemark implants and 10 CeraOne, Estheticone, Procera, and AurAdapt abutments formed the experimental populations. Samples in each group were further divided into 2 groups, 1 group was tightened with a torque controller without the use of a counter-torque device, whereas the other used the counter-torque device. Samples were positioned in a special holder within the grips of a Tohnichi BTG-6 torque gauge for measuring transmitted forces. Results. There were significant differences ( P =.0001) in the tightening forces transmitted to the implant with and without the use of a counter-torque device when tightening the abutment screws. Conclusion. An average of 91% of the recommended preload tightening torque was transmitted to the implant-bone interface in the absence of a counter-torque device. In all abutment systems, less than 10% of the recommended preload tightening torque was transmitted to the implant when the counter-torque device was used.

Statement of problem. Strength, color stability, and precision of fit are requirements for all-ceramic restorations. The Procera AllCeram crown system, composed of a densely sintered high-purity alumina core combined with a low fusing surface porcelain, appears to satisfy most of these requirements. However, evaluation of marginal fit has not been reported. Purpose. This study measured the precision of fit of the Procera AllCeram crown fabricated with Procera CAD/CAM technology for the premolar and molar teeth fit to a die. Material and methods. Five ivorine maxillary first premolars and first molars were prepared for full-coverage crowns. Preparations were standardized with a convergence angle of 10 degrees, chamfer margins of 1.3 to 1.5 mm circumferentially, and occlusal reduction of 2.0 mm. AllCeram crowns were fabricated for the dies, and the fit of the crown to the die was determined by using a standardized procedure with a silicone impression material that served a dual role: (1) as a retrievable luting agent, and (2) to replicate the internal aspects of the crown. Laser videography was used to measure the gap dimension between the crowns and the dies at the marginal opening, the axial wall, the cusp tip, and the occlusal adaptation measurement locations. Mean gap dimensions and standard deviations (SDs) were calculated for marginal opening, internal adaptation, and precision of fit. Results. Mean gap dimensions and standard deviations at the marginal opening for the premolar and molar crowns were 56.0 μm SD ± 21 and 63.0 μm SD ± 13 μm, respectively. The mean gap dimensions and SDs of the internal adaptation were 69.0 μm SD ± 17 μm for axial wall, 48.0 μm SD ± 12 μm for cusp tip, and 36.0 μm SD ± 7 μm for occlusal adaptation for the premolar crowns; and 49.0 μm SD ± 3 μm axial wall, 67.0 μm SD ± 21 μm cusp tip, and 74.0 μm SD ± 29 μm occlusal adaptation for molar crowns. Precision of fit and SDs for premolar and molar crowns were 52.0 μm SD ± 19 μm and 63.0 μm SD ± 20 μm, respectively. Mean marginal openings and precision of fit gap dimensions for the crown groups were not significantly different at the .05 level. However, gap dimensions that defined the internal adaptation at the measurement locations were different ( P ≤.05). Conclusion. Mean gap dimensions for marginal openings, internal adaptation, and precision of fit for the crown groups were below 70 μm. These findings show that the crowns studied can be prescribed with confidence knowing that the precision of fit will consistently be less than 70 μm. (J Prosthet Dent 1998;80:394-404.)

We have searched for the flavor-changing neutral current decay b -> s mu+ mu- in p pbar collisions at sqrt(s) = 1.8 TeV with the DO detector at Fermilab. We determine the 90% confidence level limit for the branching fraction to be B(b -> X_s mu+ mu-) < 3.2 x 10^{-4}. We argue that this limit is more stringent than the best published limit on this decay rate.

Statement of problem. One of the most important physical properties of artificial teeth used in the restoration of the edentulous patient is wear resistance, and the ability of these teeth to maintain a stable occlusal relationship over time. Purpose. This study compared the in vitro wear of four different resin denture teeth against human enamel. Material and methods. Five denture tooth samples opposing five enamel abraders were positioned in a mechanical wear testing device for two 5,000 cycle wear periods (total of 10,000 cycles) under a 13.4 N load. All tests were conducted in human saliva, and the wear was measured at the end of each test period. Results. The wear of the Classic and Kenson acrylic resin denture teeth was much greater than the DB Plus and MLI composite teeth after 10,000 cycles. The wear of the KENSON denture tooth was also greater than the Classic tooth. No wear differences were found between the two composite teeth. Conclusions. The wear of DB Plus and MLI resin denture teeth was approximately 50% less than the wear of Classic and Kenson teeth when opposed by human enamel. (J Prosthet Dent 1998;79:152-5.) CLINICAL IMPLICATIONS This study revealed that the composite denture teeth demonstrated significantly better wear resistance than the acrylic resin teeth. The magnitude of the wear of the different tooth types would be clinically significant in patients, depending on their dietary habits and parafunctional activities. This fact coupled with other considerations such as the cusp forms selected and the occlusal contact relationships possible with their clinical use may also influence the wear patterns experienced.

Statement of problem. Percussion, visual observation, and conventional periapical radiographs are the methods most frequently used clinically to evaluate the accuracy of implant component assemblies, whereas methods to measure the precision of fit are limited. Purpose. In this study the Periotest instrument was used to evaluate the stability of the interfaces between the implant and the abutment, along with the abutment and the gold cylinder under a series of assembly conditions. The hypothesis tested is that a more negative Periotest value (PTV) would indicate an accurate fit and a more positive value PTV would correlate with an inaccurate fit. Material and methods. To investigate this hypothesis in vitro, two bovine ribs were used as patient simulation models. Each model contained three self-tapping Branemark implants placed approximately 7 to 10 mm apart and arranged in a reasonable curvature. A series of component assembly conditions were created as accurate and inaccurate with thickness gauges of 25.4 μm, 50.8 μm, and 101.6 μm. Results. The mean Periotest values and SDs for accurately assembled abutments and gold cylinders were 6.0 ± 0.32 and 3.4 ± 0.68, respectively. Periotest value data of the assembly conditions were statistically analyzed with multiple regression analysis. The misfit in the implant to abutment interface resulted in a more negative Periotest value trend ( r = 0.54) with increases in gauge thickness. However, the same magnitudes of misfit at the abutment to gold cylinder interface produced a more positive Periotest value trend ( r = 0.72). Conclusion. The PTV trends were consistent with increased stability at the abutment to implant interface from the increasing magnitude of misfit created with the thickness gauges. In contrast, the measurement trends observed for the abutment to gold cylinder interface were consistent with decreased stability with each increase in gauge thickness inserted at the interface. (J Prosthet Dent 1997;77:497-502.)

Ligands for the type I insulin-like growth factor (IGF) receptor interact with oestrogens to control the proliferation of oestrogen responsive breast cancer cells. The aim of this study was to determine the involvement of ligands for the type I IGF receptor in the regulation of oestrogen receptor (OR) expression by oestrogens and antioestrogens in these cells. Oestrogen decreased OR mRNA levels in MCF-7 cells whereas it increased them in T47D, EFM-19 and ZR-75 cells. In MCF-7 cells, IGF-I and insulin lowered further OR expression in the presence of oestrogen. In the presence of IGF-I or insulin, the induction of progesterone receptor mRNA by oestradiol was considerably attenuated in MCF-7 cells, showing that the enhanced down-regulation of OR mRNA levels influenced the expression of oestrogen-regulated genes. The oestrogen agonist activity of the antioestrogens tamoxifen and ICI 182 780 for the down-regulation of OR expression in MCF-7 cells was modulated by type I IGF receptor ligands. Overall these experiments show that OR expression is differentially regulated by oestrogen in individual oestrogen-responsive breast cancer cell lines. Ligands for the type I IGF receptor can modulate regulation of OR expression by oestrogens and antioestrogens principally in cells in which oestrogens down-regulate OR expression.

pNR-2/pS2 is a 60 residue extracellular protein, which was originally discovered in human breast cancer cells, and subsequently found in other tumours and normal gastric epithelial cells. We have determined the three-dimensional solution structure of a C58S mutant of human pNR-2/pS2 using 639 distance and 137 torsion angle constraints obtained from analysis of multidimensional NMR spectra. A series of simulated annealing calculations resulted in the unambiguous determination of the protein's disulphide bonding pattern and produced a family of 19 structures consistent with the constraints. The peptide contains a single "trefoil" sequence motif, a region of about 40 residues with a characteristic sequence pattern, which has been found, either singly or as a repeat, in about a dozen extracellular proteins. The trefoil domain contains three disulphide bonds, whose 1-5, 2-4 and 3-6 cysteine pairings form the structure into three closely packed loops with only a small amount of secondary structure, which consists of a short alpha-helix packed against a two-stranded antiparallel beta-sheet. The structure of the domain is very similar to those of the two trefoil domains that occur in porcine spasmolytic polypeptide (PSP), the only member of the trefoil family whose three-dimensional structure has been previously determined. Outside the trefoil domain, which forms the compact "head" of the molecule, the N and C-terminal strands are closely associated, forming an extended "tail", which has some beta-sheet character for part of its length and which becomes more disordered towards the termini as indicated by (15)N{(1)H} NOEs. We have considered the structural implications of the possible formation of a native C58-C58 disulphide-bonded homodimer. Comparison of the surface features of pNR-2/pS2 and PSP, and consideration of the sequences of the other human trefoil domains in the light of these structures, illuminates the possible role of specific residues in ligand/receptor binding.

The hydrophobic residue Phe-23 lies on a surface of insulin like growth factor 1 (IGF-1) which may be involved in binding to the type I IGF and insulin receptors. The possibility that Phe-23 participates directly in binding to these receptors has been investigated by comparing the properties of [F23G]IGF-1, a mutant of insulin-like growth factor 1 in which Phe-23 has been replaced by Gly, with those of IGF-1 and insulin. [F23G]IGF-1 has a 48-fold lower affinity for the type I IGF receptor, a markedly reduced affinity for the insulin receptor and a 100-fold reduced affinity for insulin-like growth factor binding proteins (IGFBPs) compared to IGF-1. [F23G]IGF-1 is a full IGF-1 agonist as measured by its ability to stimulate cell proliferation. Its potency was only 4.5-fold less than IGF-1, probably because its bioavailability was increased as a result of its reduced affinity for IGFBPs. The large reduction in the affinity of [F23G]IGF-1 for the type I IGF receptor and insulin receptor contrasts with the lack of effect of the corresponding alteration to insulin [FB24G]. Phe-B24 is not thought to be involved directly in the binding of insulin to the insulin receptor and the C-terminus of the B-chain of insulin is suggested to be displaced on binding. We suggest that for IGF-1, the C-terminus of the B chain cannot be displaced because of the presence of the C-domain and the large reduction in the binding affinities of [F23G]IGF-1 suggest that the Phe-23 side chain may be directly involved in binding of IGF-1 to the type I IGF and insulin receptors.

We have studied J ψ production in p p collisions at s = 1.8 TeV with the DO detector at Fermilab using μ+μ− data. We have measured the inclusive J ψ production cross section as a function of J ψ transverse momentum, pT. For the kinematic range pT > 8 GeV/c and |η| σ(p p → J ψ + X) · Br ( J ψ → μ + μ − ) = 2.08 ± 0.17( stat) ± 0.46(syst) nb. Using the muon impact parameter we have estimated the fraction of J ψ mesons coming from B meson decays to be fb = 0.35 ± 0.09(stat)±0.10(syst) and inferred the inclusive b production cross section. From the information on the event topology the fraction of nonisolated J ψ events has been measured to be fnonisol = 0.64 ± 0.08(stat)±0.06(syst). We have also obtained the fraction of J ψ events resulting from radiative decays of χc states, fχ = 0.32 ± 0.07(stat)±0.07(syst). We discuss the implications of our measurements for charmonium production processes.

The distribution of the transverse energy in jets has been measured in p p collisions at s =1.8 TeV TeV using the DO detector at Fermilab. This measurement of the jet shape is made as a function of jet transverse energy in both the central and forward rapidity regions. Jets are shown to narrow both with increasing transverse energy and with increasing rapidity. Next-to-leading order partonic QCD calculations are compared to the data. Although the calculations qualitatively describe the data, they are shown to be very dependent on renormalization scale, parton clustering algorithm, and jet direction definition and they fail to describe the data in all regions consistently.

A search for a heavy charged gauge boson, W′, using the decay channels W′ → eν and W′ → τν → eνν ν is reported. The data used in the analysis were collected by the DO experiment at the Fermilab Tevatron during the 1992-93 p p collider run from an integrated luminosity of 13.9 ± 0.8 pb−1 at s =1.8 TeV . Assuming that the neutrino from W′ decay is stable and has a mass significantly less than mW′, an upper limit at the 95% confidence level is set on the cross section times branching ratio for p p → W′ → eν . A W′ with the same couplings to quarks and leptons as the standard model W boson is excluded for mW′

The machined surface of wrought titanium frameworks used in implant-supported, fixed prostheses does not bond well with acrylic resin. Surface pretreatment has been suggested to enhance the retention of polymethyl methacrylate to machined titanium surfaces. This study evaluated a new bonding material (Rocatec) to determine its effect on the bond strength between titanium and polymethyl methacrylate. Twenty rod-shaped specimens of grade 2 titanium (7.6 x 0.3 cm in diameter) were divided into two groups of 10 samples. Group A received no pretreatment and group B was pretreated with 110 microns alumina air abrasive and the Rocatec material. Heat-cured denture base resin was processed around each titanium sample in a cylindrical shape approximately 0.9 x 1.5 cm. A Shell-Nielsen shear test was performed with a universal testing machine at a crosshead speed of 0.5 mm/minute to determine the bond strength in megapascals (MPa). Group B specimens (23.8 +/- 1.78 MPa) had a shear strength 68% greater than group A (16.1 +/- 1.61 MPa) (p 0.0001). The results of this study indicated that surface pretreatment of grade 2 titanium with 110 microns alumina air abrasive plus Rocatec bonding material significantly enhances the shear bond strength to PMMA.

Moire interferometry with line densities of 1200 and 40 lines per mm was used to determine the two orthogonal displacements surrounding a stably extending crack in a 2024-T3 aluminum alloy, single edge cracked specimen. The test protocol consisted of using the fine moire grating prior to and up to the onset of crack extension and the coarse moire grating for the ensuing crack extension up to Δa = 6 mm. The displacement fields were used to compute the J-integrals for various contours during crack tip blunting and crack extension. As expected, the far-field J-integral value prior to stable crack growth coincided with the LEFM strain energy release rate G, and validated the experimental procedure. However, the J values obtained from the near tip contour increased slowly, while the far-field J values increased rapidly with increasing stable crack growth. The HRR displacement field was computed from the experimentally determined far-field J. The HRR displacement field agreed with the measured displacement field prior to stable crack growth since J = G. However, the HRR horizontal displacement field progressively deviated from the measured values with crack extension.

Background & Aims Hepatocellular carcinoma (HCC) can develop in individuals without cirrhosis. We investigated risk factors for development of HCC in the absence of cirrhosis in a U.S. population. Methods We identified a national cohort of 1500 patients with verified HCC during 2005 to 2010 in the U.S. Veterans Administration (VA) and reviewed their full VA medical records for evidence of cirrhosis and risk factors for HCC. Patients without cirrhosis were assigned to categories of level 1 evidence for no cirrhosis (very high probability) or level 2 evidence for no cirrhosis (high probability), which were based on findings from histologic analyses, laboratory test results, markers of fibrosis from noninvasive tests, and imaging features. Results A total of 43 of the 1500 patients with HCC (2.9%) had level 1 evidence for no cirrhosis, and 151 (10.1%) had level 2 evidence for no cirrhosis; the remaining 1203 patients (80.1%) had confirmed cirrhosis. Compared with patients with HCC in presence of cirrhosis, greater proportions of patients with HCC without evidence of cirrhosis had metabolic syndrome, nonalcoholic fatty liver disease (NAFLD), or no identifiable risk factors. Patients with HCC without evidence of cirrhosis were less likely to have abused alcohol or have hepatitis C virus infection than patients with cirrhosis. Patients with HCC and NAFLD (unadjusted odds ratio, 5.4; 95% confidence interval, 3.4–8.5) or metabolic syndrome (unadjusted odds ratio, 5.0; 95% confidence interval, 3.1–7.8) had more than 5-fold risk of having HCC in the absence of cirrhosis, compared with patients with HCV-related HCC. Conclusions Approximately 13% of patients with HCC in the VA system do not appear to have cirrhosis. NAFLD and metabolic syndrome are the main risk factors for HCC in the absence of cirrhosis.

The mechanism by which steroids influence cell proliferation is poorly understood although an understanding of this proces might facilitate the development of strategies to modulate the tissue-specific activity of steroid hormones. In this article, the evidence that steroid hormones interact with the insulin-like growth factor (IGF) signal transduction pathway is reviewed for three different tissues. In osteoblasts, oestradiol stimulates the production of IGF-I which appears to act as an autocrine growth factor. In uterine tissue, oestradiol increase the synthesis of IGF-I in the stroma which then modulates the proliferation of epithelial cells although there is also evidence that oestradiol can modulate the sensitivity of uterine epithelial cells to IGFs. In breast cancer, oestrogens may increase IGF-II synthesis in epithelial cells, increase the sensitivity of breast cancer cells to IGFs (possibly by modulating type IIGF receptor levels) as well as resulting components of the IGF signal transduction pathway resulting in induction of immediate early genes. There therefore appears to be a variety of ways in which oestradiol interact with the IGF signal transduction pathway and these may be applicable to other malignant and normal tissues and other groups of steroid hormones.

A young man in Germany was bitten by a large captive saw-scaled viper (Echis 'pyramidum'-complex) of Tunisian origin. During the first few hours after the bite he developed evidence of disseminated intravascular coagulation and fibrinolysis, and bled spontaneously. Despite being given a total of 310 ml of three different Echis-specific antivenoms (together with large amounts of fresh frozen plasma and concentrated clotting factors), venom antigenaemia (measured by enzyme immunoassay) and coagulopathy persisted for more than 10 days, and he developed a haemolytic anaemia and mild renal dysfunction. Transient bilateral ptosis was attributed to envenoming. The venom of the snake responsible for the bite was immunologically distinct from that of Nigerian E. ocellatus and was clearly not neutralised by the three monospecific antivenoms which had been administered. This case is another illustration of the geographical variation in snake venoms and the need for pooling venoms from snakes from different parts of the geographical range in the preparation of antivenoms. Envenoming by North African Echis species may not be reversible by available antivenoms.

Alginate is an important virulence factor of Pseudomonas aeruginosa, a bacterium that colonizes the pulmonary tracts of cystic fibrosis patients. Alginate is also widely used in the food, pharmaceutical and chemical industries, and consequently there is considerable interest in the molecular biology and biochemistry of alginate synthesis. As well as its therapeutic potential, research on mucoid P. aeruginosa may provide a lead to an alternative source of alginate for industrial use.

Phosphomannose isomerase-guanosine 5'-diphospho-D-mannose pyrophosphorylase (PMI-GMP), which is encoded by the algA gene, catalyzes two noncontiguous steps in the alginate biosynthetic pathway of Pseudomonas aeruginosa; the isomerization of D-fructose 6-phosphate to D-mannose 6-phosphate and the synthesis of GDP-D-mannose and PPi from GTP and D-mannose 1-phosphate. Amino acids that are required for the GMP enzyme activity were identified through site-directed mutagenesis of the algA gene. Mutation of Lys-175 to arginine, glutamine, or glutamate produced an enzyme whose Km for D-mannose 1-phosphate was 470-3,200-fold greater than that measured for the wild type enzyme. In addition, these mutant enzymes had a lower Vmax for the GMP activity as compared with the wild type PMI-GMP. These results indicate that Lys-175 is primarily involved in the binding of the substrate D-mannose 1-phosphate, although it is likely that other residues are required for the specificity of binding. Mutation of Arg-19 to glutamine, histidine, or leucine resulted in a 2-fold lower Vmax for the GMP enzyme activity and a 4-7-fold increase in the Km for GTP as compared with the wild type enzyme. Thus, it appears that Arg-19 functions in the binding of GTP. In addition, chymotryptic digestion of PMI-GMP showed that the carboxyl terminus is critical for PMI activity but not for GMP activity. Taken together, these results support the hypothesis that the bifunctional PMI-GMP protein is composed of two independent enzymatic domains.

The alginate lyase-encoding gene ( algL ) of Pseudomonas aeruginosa was localized to a 1.7-kb Eco RI- Xba I fragment within the alginate biosynthetic gene cluster at 34 minutes on the chromosome. The nucleotide sequence of this DNA fragment revealed an ORF encoding a protein of M r 40 885 which is transcribed in the same orientation as the other alg genes within the biosynthetic gene cluster. The predicted protein has a potential N-terminal signal peptide which is consistent with its proposed periplasmic location. The AlgL protein was overproduced in Escherichia coli and purified. The purified protein was shown to have alginate lyase activity. In addition, an algL insertion mutant of the mucoid P. aeruginosa 8830 was constructed. This mutant (alml) had a nonmucoid phenotype due to a polar effect on the transcription of an essential alg gene, algA . Thus, the algL gene is located within a region of the alginate biosynthetic gene cluster that appears to be non-essential for alginate production.

Moire interferometry is employed to study toughening in partially stabilized zirconia (PSZ). Energy to fracture as a function of crack growth curves ( R -curves) is derived from mode I compliance calculations and from near tip fitting of the moire fringes. The effect of the tetragonal to monoclinic phase transformation in the zirconia is found by comparing the bulk compliance R -curves to the locally derived moire R -curve. Localized strain field plots are produced from the moire data for the PSZ zirconia. The observed transformation zone height compares favorably with that predicted by Okada et al. [ Acta metall. mater. 40 , 1421 (1992)] in a companion paper, as does the qualitative nature of the R -curve with predictions by Stump and Budiansky [ Acta metall. 37 , 3297 (1989)].

Erythrocyte macrocytosis is noted in patients taking valproate with serum levels > 100 μg/ml. We postulated valproate affects membrane structure directly by altering membrane phospholipids. Patients were selected from a chronic care facility, had known static encephalopathy, were generally healthy, and on valproate monotherapy. Red cells were obtained from three groups: macrocytic with serum levels > 100 μg/ml (Group 1), normocytic with serum levels 100 μg/ml. Macrocytosis may be reflective of this biochemical, concentration-specific effect.

The use of metal based bipolar plates in polymer electrolyte membrane (PEM) fuel cells, with an active coating on titanium to reduce voltage losses due to the formation of passive layers has been demonstrated. Lifetime data in excess of 8000 h has been achieved and power densities in excess of 1.8 kW dm −3 and 1 kW kg −1 are predicted.