Standard Cap Research Articles

Processive capping by formin suggests a force-driven mechanism of actin polymerization

Regulation of actin polymerization is essential for cell functioning. Here, we predict a novel phenomenon—the force-driven polymerization of actin filaments mediated by proteins of the formin family. Formins localize to the barbed ends of actin filaments, but, in contrast to the standard capping proteins, allow for actin polymerization in the barbed direction. First, we show that the mechanism of such “leaky capping” can be understood in terms of the elasticity of the formin molecules. Second, we demonstrate that if a pulling force acts on the filament end via the leaky cap, the elastic stresses can drive actin polymerization. We estimate that a moderate pulling force of ∼3.4 pN is sufficient to reduce the critical actin concentration required for barbed end polymerization by an order of magnitude. Furthermore, the pulling force increases the polymerization rate. The suggested mechanism of force-driven polymerization could be a key element in a variety of cellular mechanosensing devices.

Protection of the patient's hair with a standard swimming cap during major maxillofacial operations

During maxillofacial operations there is inevitably a lot of blood shed, which soils the patients hair. The cleaning of blood stained hair is a laborious and time-consuming task, particularly after a long operation. To prevent this we advocate using a standard swimming cap to protect the hair.

Irrinotecan hydrochloride (CPT-11) and mitomycin C in ovarian clear cell adenocarcinoma

5129 Background:The purpose of this study was to report the results of adjuvant CPT-11 and MMC combination chemotherapy (CPT-M) for ovarian clear cell adenocarcinoma (OCCA). Methods:Between 1996 and 2001, patients with OCCA underwent primary debulking surgery and received two cycles of CPT-11 (140 mg/m2) in combination with MMC (7 mg/m2) on days 1, 15, 29 in adjuvant setting. Overall survival was compared with our historical control, in which 14 patients with OCCA treated with an initial optimal standard surgery and postoperative adjuvant CAP (cyclophosphmide, doxorubicin, cisplatin). Results:Median age was 52 year-old (range, 29–74). Twelve patients were in stage Ic, 1 in stage IIa, 5 in stage IIc, 1 in stage IIIb, and 1 in stage IV. Optimal cytoreduction with standard surgery was obtained in all 20 patients. The major toxicity with this regimen was neutropenia, which was brief and reversible. The incidences of grade 3 and 4 neutropenia were 38% and 15%, respectively. The non-hematological toxicities were generally mild and well tolerated. One patient with stage Ic refused chemotherapy after the first cycle of CPT-M, and died of her disease 8 months after initial surgery. Five-year survival rate was 94.1% for CPT-M group, and 63.4% for CAP group (p=0.128). Survival was better for patients treated with CPT-M. Conclusions:This preliminary study shows that the combination of CPT-M appears to be safe and useful in patients with OCCA. Prospective randomized trials should be conducted to assess this regimen appropriate for women with OCCA. No significant financial relationships to disclose.

Standard and alternative landfill capping design in Germany

Abstract Engineered capping systems are in most cases an indispensable and often the only efficient component required by the long-term safety concept for landfills, mine tailings tips and contaminated land. In Germany the composite liner is the main component of standard landfill cappings for municipal and hazardous waste landfills and the compacted clay liner (CCL) for landfills for inert or low-contamination waste. The composite liner is a technically highly effective but very expensive system. Research and experience has given rise to concern about the proper long-term performance of a conventional single CCL as a landfill capping. Therefore, alternative capping systems are discussed and applied for landfills and for the containment of contaminated sites. This paper gives an overview on various alternative engineered cappings and suitable systems for capping reflecting the state of the art and the expert view in Germany. According to the European Council Directive on the landfill of waste an impermeable mineral layer is recommended for the surface sealing of non-hazardous landfills and a composition of artificial sealing liner and impermeable mineral layer for hazardous landfills. In both cases a drainage layer thickness of at least 0.5 m is suggested. These recommendations should be interpreted flexibly and to some extent modified in the light of the experience and results presented in this paper.

Combo cap takes a big bite, yet a smoothie to swallow

Combo cap takes a big bite, yet a smoothie to swallow

Effects of occlusiveness of a titanium cap on bone generation beyond the skeletal envelope in the rabbit calvarium

We evaluate the effects of occlusiveness of a titanium cap on bone generation beyond the skeletal envelope. In eight rabbits, the calvarial bone was exposed and a circular groove was prepared with a trephine drill. After marrow penetration, a standardized hemispherical titanium cap, either with or without small holes (1.5 mm in diameter), was then placed into the bone and covered by a cutaneous flap. After 1 month or 3 months of healing, the animals were euthanized and examined histologically. The percentage area of newly generated tissue consisting of mineralized bone and marrow spaces in each section was calculated relative to the area bounded by the hemispherical shape of the titanium cap and the parent bone; this latter volume was taken to be 100%. Furthermore, the cross-sectional areas of generated mineralized bone expressed as percentages of the total tissue area generated within each space were determined. In the 1-month specimens, there was no statistically significant difference between the two caps in the amount of tissue generated, 54.7%+/-12.2% with holes vs. 60.4%+/-8.8% without holes (p=0.225). However, in the 3-month specimens, we observed a significant difference between the caps (55.9%+/-7.4% with holes vs. 89.9%+/-6.5% without holes, P<0.05). Also, there was a statistically significant difference between 1- and 3-month specimens in the amount of tissue generated under the cap without holes (60.4%+/-8.8% vs. 89.9%+/-6.5%, P<0.05). Although there was no significant difference in the relative amount of mineralized bone generated between the caps with holes and those without holes in the 1-month specimens (27.7%+/-4.8% vs. 30.8%+/-6.4%, P=0.225), there was a statistically significant difference between the two caps in the 3-month specimens (24.3%+/-4.1% with holes vs. 34.0%+/-8.6% without holes, P<0.05). A substantial ingrowth of fibrous connective tissue through the holes appeared to prevent further new tissue generation in a defined area adjacent to the bone surface. We concluded that total occlusiveness, sufficient stiffness of the cap, as well as the passage of time will allow predictable mineralized bone augmentation to occur in spaces beyond the skeletal envelope.

A randomized, prospective clinical trial to assess the potential infection risk associated with the PosiFlow ® needleless connector

The microbial contamination rate of luers of central venous catheters (CVCs) with either PosiFlow ® needleless connectors or standard caps attached was investigated. The efficacy of 70% (v/v) isopropyl alcohol, 0.5% (w/v) chlorhexidine in gluconate 70% (v/v) isopropyl alcohol and 10% (w/v) aqueous povidone–iodine to disinfect the intravenous connections was also assessed. Seventy-seven patients undergoing cardiac surgery who required a CVC as part of their clinical management were randomly allocated either needleless connectors or standard caps. Patients were also designated to receive chlorhexidine/alcohol, isopropyl alcohol or povidone–iodine for pre-CVC insertion skin preparation and disinfection of the connections. After 72 h in situ the microbial contamination rate of 580 luers, 306 with standard caps and 274 with needleless connectors attached, was determined. The microbial contamination rate of the external compression seals of 274 needleless connectors was also assessed to compare the efficacy of the three disinfectants. The internal surfaces of 55 out of 306 (18%) luers with standard caps were contaminated with micro-organisms, whilst only 18 out of 274 (6.6%) luers with needleless connectors were contaminated ( P<0.0001). Of those needleless connectors disinfected with isopropyl alcohol, 69.2% were externally contaminated with micro-organisms compared with 30.8% disinfected with chlorhexidine/alcohol ( P<0.0001) and 41.6% with povidone–iodine ( P<0.0001). These results suggest that the use of needleless connectors may reduce the microbial contamination rate of CVC luers compared with the standard cap. Furthermore, disinfection of needleless connectors with either chlorhexidine/alcohol or povidone–iodine significantly reduced external microbial contamination. Both these strategies may reduce the risk of catheter-related infections acquired via the intraluminal route.

Automated liner exchange— A novel approach in direct thermal desorption— gas chromatography

A system was developed for fully automated liner exchange in direct thermal desorption— gas chromatography— mass spectrometry (DTD-GC-MS). Samples are put into a newly developed liner which is capped with a standard crimp cap. The liners are placed in a sample tray and transported to the thermal desorption device. Both liner transport and liner exchange (which can be performed after each analysis) are automated. The system was tested for spores and pollen, vegetable oil, wood (preservative), car exhaust (BTEX), and tobacco (nicotine) analysis to demonstrate the robustness and flexibility of the approach.

A prospective clinical study toinvestigate the microbial contamination ofa needleless connector

Needleless connectors, which allow direct access to intravascular catheters, are widely used in clinical practice. The benefits of these devices to healthcare workers are well documented; however, the potential risk of microbial contamination and associated infection is unclear. This clinical study evaluated microbial contamination rates for a needleless connector, Connecta Clave® (CC®), as compared to a conventional three-way tap, which was connected to the hubs of central venous catheters (CVC) immediately following insertion. Patients in the study group had CC® attached to the three-way taps, whereas the control group had standard entry port caps. On removal (up to 72h) the connectors were studied for microbial contamination. There was no significant difference between the number of three-way taps contaminated on the internal surface with micro-organisms in the control group with entry port caps (19/132, 14%) compared to the group with CC® (18/105, 17%). Sixteen percent (27/173) of the CC® were contaminated with micro-organisms on the internal surfaces. The external surface of 33% (27/82) of the CC® silicone seals were contaminated after clinical use. Micro-organisms were also isolated from 9% (8/91) of the silicone seals after disinfection. The use of this needleless connector, compared to standard caps therefore does not appear to increase the risk of infection via the internal lumen of three-way taps.

Valuing Energy Options in a One Factor Model Fitted to Forward Prices

In this paper we develop a single-factor modeling framework which is consistent with market observable forward prices and volatilities. The model is a special case of the multi-factor model developed in Clewlow and Strickland [1999b] and leads to analytical pricing formula for standard options, caps, floors, collars and swaptions. We also show how American style and exotic energy derivatives can be priced using trinomial trees, which are constructed to be consistent with the forward curve and volatility structure. We demonstrate the application of the trinomial tree to the pricing of a European and American Asian option. The analysis in this paper extends the results in Schwartz [1997] and Amin, et al. [1995].

Localized Kerr-type nonlinearities in GaAs/AlGaAs multiple quantum well structures at 1.55 μm

We report the use of a novel impurity free vacancy disordering technique which has been used to produce waveguides with different Kerr-type nonlinear coefficients. The technique relies on standard SiO2 dielectric caps to promote disordering and Ga2O3 caps to suppress disordering. Band-gap shifts of around 40 nm and consequent changes in n2 of more than 60% are reported.

A Radiocarbon Dating Protocol for use with Packard Scintillation Counters Employing Burst-Counting Circuitry

Considerable research has been carried out in this laboratory on the use of Packard scintillation counters employing burst-counting circuitry. The nature of the pulse-shape discrimination circuit has led to redefining our sample vialing philosophy and scintillation cocktail optimization. Results presented here demonstrate: 1) the enhancements in efficiency that are achievable using a two-component cocktail compared with the use of a primary fluor only; 2) the development of a cocktail in which efficiency and quenching are relatively unaffected by moderate variations in fluor concentrations and ratio; 3) the rationale behind the use of screw-cap vials rather than sealable ampules; 4) the advantage of nickel/chromium-plated brass caps over standard plastic caps.

Synthesis of well-defined phosphate-methylated DNA fragments: the application of potassium carbonate in methanol as deprotecting reagent

A new deprotection procedure in the synthesis of (partially) phosphate-methylated oligodeoxynucleotides has been developed, involving treatment of fully protected DNA fragments with methanolic potassium carbonate. It is shown that base deprotection can be accomplished in potassium carbonate/methanol without affecting the methyl phosphotriesters. This methodology enables us to synthesize, both in solution and on a solid support, DNA fragments which are phosphate-methylated at defined positions. The solid phase synthesis, however, turns out to be accompanied by considerable demethylation of the phosphotriesters. It is demonstrated that this demethylation does not occur during the deprotection or work-up procedure. Furthermore, it was found that the latter side-reaction is suppressed when the standard capping procedure with acetic anhydride is included.

The broadgreen osteotomy splint

A modification is suggested to the standard cast metal cap splint which allows accurate and easier localisation in the operative and post-operative phases.

Response to aluminum in parenteral nutrition during infancy

The response to aluminum loading from parenteral nutrition (PN) solutions was determined in 20 infants with gestational ages 29 to 41 weeks and birth weights 880 to 3630 gm. Mean duration of PN was 43 days (range 5 to 175 days). Ten infants received a high Al load (from an experimental high calcium- and phosphorus-containing PN solution, with a measured Al content of 306 +/- 26 micrograms/L (mean +/- SE), n = 11), for up to 6 weeks. Ten infants received a lower Al load (from standard Ca-P solutions, measured Al content 144 +/- 16 micrograms/L, n = 11). Five infants received PN with a low Al load for longer than 6 weeks. The mean urine Al/creatinine (Cr) ratio (micrograms/mg) increased threefold, from 0.3 +/- 0.09 to 0.97 +/- 0.17 during PN in the entire group (P less than 0.001), and was significantly higher in infants who received greater Al loading (P less than 0.001). There was no significant difference between preterm and term infants in the rate of change in urine Al/Cr during the study. Urine Al was calculated to account for less than 50% of Al load. During the study, serum Al concentrations ranged from 6 to 318 micrograms/L (median 37 micrograms/L, compared with the median 18 micrograms/L for normal infants and children). Serum Al concentrations were not significantly changed during the study, or between infants in high or lower Al loading groups. Vertebrae from autopsy of two infants who received the lower Al containing PN for 71 and 152 days, respectively, stained positive for Al at the bone mineralization front. Thus, currently used PN solutions are contaminated with Al, urine Al concentration is higher with higher Al loading, and is not different in term and preterm infants. We suggest that renal elimination of Al in infants is incomplete, as assessed by lower urine Al excretion versus load, elevated serum Al concentration, and bone deposition of Al.

Tests of Synthetic Apple Volatiles in Traps as Attractants for Apple Maggot Flies (Diptera: Tephritidae) in Commercial Apple Orchards

Tests of three types of traps for apple maggot flies ( Rhagoletis pomonella [Walsh]) in 25 commercial orchards in 1982 and 20 orchards in 1983 showed that red spheres baited with synthetic apple volatiles were 2- to 4-fold as effective as unbaited spheres, and more than 50-fold as effective as Pherocon AM yellow panels. Polyethylene vials that released volatiles through the season were as effective as standard polyethylene caps that were replaced twice weekly during the summer. The traps were equally effective in all the apple cultivars used in the trials. In contrast, tests conducted in two abandoned unsprayed orchards, which were heavily infested with apple maggots, showed no significant differences in catches between the baited and unbaited spheres.

Visco‐damage tension model for rocks in ground‐shock applications

AbstractA simple rate‐dependent tension model, tailored primarily for rocks in ground‐shock calculations, has been constructed. It is formulated as an internal state variable theory with spherical void development taken to approximate the underlying dissipative micromechanism. This simplifying assumption of ductile, rather than brittle, damage growth has been made to enhance the practicality of the model for large‐scale problems. The model has been restated within the fromework of (strain‐softening) viscoplastcity to associate it with the desirable mathematical properties of the latter theory. The tension option, extended to include healing in the post‐damage compressive phase, has been implemented in a standard cap constitutive routine and is referred to as the visco‐damage tension model. Model parameters are selected for a shale‐like material. Results of uniaxial shock‐loading strain‐rate calculations exhibit desired characteristics in tension. Damage‐related hysteretic effects are illustrated through cyclic loading calculations. It is planned to develop more effecient computational procedures to facilitate adoption of the model into large‐scale ground shock calculations. Anisotropic extensions of the model will then be considered.

Instrumentation for the Farnsworth-Munsell 100-hue test*

Standard Farnsworth-Munsell (F-M) disks and caps are numerically encoded in a two-digit, base-five, system using resistors and zener diodes connected to miniature jack plugs. When the subject orders the disks in the usual way, he connects the plugs to sockets that are in turn connected to an electronic processor. The various error scores are computed, and the error-versus-position graph plotted by a pen recorder, in a total time of between 0.5 and 2.5 min.

ANFO爆薬の起爆特性について

In this paper, some problems about propertv of ANFO mixtures is examined, to change our easy preconception.Each conclusion about these is as follows.(1)The condition of confinement is one of the most important factor to initiate ANFO.Even enough amount of primer can not initiate ANFO (permitted by JIS) without adequate condition of confinement.On the contrary, if the condition of confinement is adequate ANFO can be initiated perfectly only with a No.6 cap (it is standard cap in Japan).(2)Lead block expanding test for ANFO can be carried out without any modification.Ballistic mortar test can also be done with such a simple modification as to pack ANFO with aluminum foil and to stick the bottom of it to the end wall of chamber, or as to charge ANFO into a cylindrical tin foil with a tin plate on the bottom of it.and to explode it in the middle of chamber, so as to promote the cavity effect of cap. For reference, R.W.S of ANFO is 81.2.(3) Ordinary necessary amount of primer should not be decided per total amount of ANFO in bore hole, but per diameter of bore hole.(4)A postscript: ANFO which is exposed below the temperature of-18°C apt to break into fine particle, consequently, it is become more Sensitive.

The Alignment of the Cheistov High Intensity Grip Cap in the Rca Emu-3 And Emu-U Electron Microscopes

The Christov high intensity grid cap (1,2) is being used in RCA EMU-3 and EMU-U electron microscopes with increasing frequency as more investigators are discovering the augmentation of the illumination which permits easy and accurate focus at all magnifications. However, as some operators are not too familiar with the alignment of the new grid cap, it is our purpose to present a simple method of alignment.Because of the small aperture in the high intensity grid cap, it requires cleaning more often than the standard cap. The filament is aligned in the gun using the filament alignment tool as usual. Then the high intensity cap (held in a lens paper) is carefully threaded onto the gun assembly with the three nylon screws threaded in place so that they do not protrude inside of the cap.