bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in the lignin-carbohydrate complex in softwood kraft pulp during kraft and oxygen delignification
Authors: Lawoko Martin , Berggren Rickard , Berthold Fredrik , Henriksson Gunnar , Gellerstedt Göran
Published: October 2004

Three kraft pulps in the kappa number range between 50 and 20 and the same pulps oxygen-delignified to similar lignin contents (kappa approximately 6) were analyzed for lignin-carbohydrate complexes (LCC) by a method based on selective enzymatic hydrolysis of the cellulose, and quantitative fractionation of the LCC. Between 85 and 90% of residual lignin in the unbleached kraft pulp and all residual lignin in the oxygen-delignified pulps were isolated as LCC. Three types of complexes were found; viz., xylan-lignin, glucomannan-lignin-xylan and glucanlignin complexes. After pulping to a high kappa number, most of the residual lignin was linked to xylan. Different delignification rates were observed so that most of the residual lignin was linked to glucomannan when the pulping was extended to a low kappa number. With increasing degree of oxygen delignification, a similar trend in the delignification rates of LCC was observed so that the residual lignin was increasingly linked to glucomannan. Complex LCC network structures seemed to be degraded into simpler structures during delignification. The differences in delignification rates are discussed with reference to the solubility properties and structural differences of LCC, and to morphological aspects of the pulp.
Carbohydrate structures in residual lignin-carbohydrate complexes of spruce and pine pulp
Authors: Laine Christiane , Tamminen Tarja , Hortling Bo
Published: October 2004

Residual lignin carbohydrate complexes (RLCC) were isolated enzymatically from spruce and pine pulp. The RLCCs contained 4.9–9.4% carbohydrates, with an enrichment of galactose and arabinose compared to the original pulp samples. The main carbohydrate units present in all studied RLCCs were 4-substituted xylose, 4-, 3- and 3,6-substituted galactose, 4-substituted glucose and 4 and 4,6-substituted mannose. These units were assigned to carbohydrate residues of xylan, 1,4- and 1,3/6-linked galactan, cellulose and glucomannan.

RLCCs of surface material and the inner part of spruce kraft pulp fiber were compared to obtain information on the heterogeneity of layers of the fiber wall. The 1,4-linked galactan was the major galactan in RLCC of fiber surface material of spruce kraft pulp. Towards the inner part of the fiber, the proportion of 1,3/6-linked galactan increased relative to 1,4-linked galactan. This finding is presented for the first time. 1,3/6-Linked galactan structures are suggested to have a role in restricting lignin removal from the secondary fiber wall.

RLCCs of three different alkaline pine pulps were studied before and after oxygen delignification to evaluate differences resulting from the cooking method. The pulps were conventional kraft pine pulp (PCK), a polysulfide/anthraquinone pine pulp (PPSAQ) and a soda/anthraquinone pine pulp (PSoAQ); all were cooked to approximately kappa number 30. Small differences were found in the carbohydrate structures of the unbleached pulps. The study indicated that the RLCC of unbleached PSoAQ pulp contained longer oligomeric carbohydrate chains and less branched 1,3/6-linked galactan residues than the RLCCs of unbleached PCK and PPSAQ pulps. The RLCC of the unbleached PSoAQ also contained more 1,4-linked glucose units suggesting a greater number of linkages of lignin to cellulose in the PSoAQ pulp than in the other two pulps. All RLCCs of oxygen-delignified pulps had more non-reducing ends and less 1,3/6-linked galactan than the corresponding RLCCs of the unbleached pulps. The RLCC of the oxygen-delignified PSoAQ pulp had a higher ratio of 1,4-galactan to 1,3/6-linked galactan and shorter xylan residues than the RLCCs of oxygen-delignified PCK and PPSAQ pulps.
Ozonation of pine kraft lignin in alkaline solution. Part 1: Ozonation, characterization of kraft lignin and its ozonated preparations
Authors: Wang Rui , Chen Chen-Loung , Gratzl Josef S.
Published: October 2004

Pine kraft lignin was purified to obtain a kraft lignin preparation (KL) with weight average molecular mass (Mw) of 5500. The KL was then ozonated with an ozone-air stream containing 2–2.5% of ozone in 0.1 M sodium hydroxide solution to prepare ozonated kraft lignin preparations with ozone consumption of 10, 25, 30 and 40% per KL; Oz-10-KL, Oz-25-KL, Oz-30-KL and Oz-40-KL, respectively. The pH of reaction mixture was decreased with increasing ozone consumption, while the carboxylic acid content and the Mw of resulting ozonated lignins increase with increasing ozone consumption. The KL and its ozonated preparations were then characterized by elemental composition, functional group analysis, molecular mass distribution and nitrobenzene-K4MnO4 oxidation. The results showed that the KL extensively undergoes oxidative cleavage of both side chains and aromatic moieties without decrease in the Mw as well as dehydrogenationive coupling of phenolic degraded fragments by active oxygen radical species, such as hydroperoxyl and hydroxyl radicals. The formation of these active oxygen radical species are produced by way of a series of reactions initiated by the reaction of ozone with hydroxide anions at pH range of 12.4–10.5, producing superoxide (-O2•) and hydroperoxyl (HOO•) radicals.
Ozonation of pine kraft lignin in alkaline solution. Part 2: Surface active properties of the ozonated kraft lignins
Authors: Wang Rui , Chen Chen-Loung , Gratzl Josef S.
Published: October 2004

The surface tension and interfacial tension of the F-1000, F-1800, F-5000 and F-15000 fractions obtained by ultrafiltration of the Oz-25-KL, Oz-30-KL and Oz-40-KL preparations (ozonated kraft lignin, KL, preparations with ozone consumption of 25, 30 and 40% per KL) were determined with the concentration range of 1–30 g l-1 at pH of 6, 9 and 11. The surface tension of these ozonated KL preparations decreased with increasing concentration and pH according to the simplified Gibbs adsorption equation for dilute aqueous solution, ∂γ= -RTΓ∂(ln C). The results were discussed in term of functional group contents and weight average molecular mass (Mw) of the ozonated KL preparations. The surface tension of the ozonated KL preparations decreased with increasing carboxylic acid content and, to some extent, phenolic hydroxyl content, but increased with increasing Mw. The synergistic effect of the ozonated KL preparations with a commercial surfactant was then investigated. The oil-water interfacial tension was determined in the ozonated KL preparations in an aqueous solution containing 1.5% Petrostep B-120R and 1.5% sodium chloride with hexane as oil phase by spinning drop technique. The interfacial tension of the system also decreased with increasing the concentration of ozonated KL preparations in the range of 1–16 g l-1 according to the simplified Gibbs adsorption equation. Thus, the addition of a small amount of ozonated KL preparations to the aqueous solution containing 1.5% Petrostep B-120R and 1.5% sodium chloride showed a remarkable synergistic effect on reducing the interfacial tension.
Lignin reactions in oxygen delignification catalysed by Mn(II)-substituted molybdovanadophosphate polyanion
Authors: Gaspar Armindo , Evtuguin Dmitry V. , Pascoal Neto Carlos
Published: October 2004

The lignin oxidation in the oxygen delignification/bleaching process catalysed by Mn(II) substituted heptamolybdopentavanadophosphate polyanion (HPA-5-MnII) was studied using monomeric lignin model compounds and Eucalyptus globulus dioxane lignin adsorbed on the bleached sulphite pulp. The analysis of reaction products after lignin models oxidation in the presence HPA-5-MnII and the parent heptamolybdopentavanadophosphate polyanion (HPA-5) showed similar qualitative and quantitative patterns, indicating the identical lignin oxidative delignification mechanisms with both catalysts. The higher delignification selectivity of the pulp in the reaction system HPA-5-MnII/O2 than with HPA-5/O2 was explained by the protective effect of MnII in the heteropolyanion towards oxidative degradation of polysaccharides. The study of lignin adsorbed on bleached sulphite pulp, in the HPA-5-MnII/O2 delignification system, showed the cleavage of β-O-4 linkages as the major contribution to the lignin depolymerisation. The formation of Cα-O-polysaccharide linkages in β-O-4 structures of lignin during the delignification was observed.
Bioactive phenolic substances in industrially important tree species. Part 2: Knots and stemwood of fir species
Authors: Willför Stefan , Nisula Linda , Hemming Jarl , Reunanen Markku , Holmbom Bjarne
Published: October 2004

Knots, i.e. branch bases inside tree stems, in fir trees contained remarkably higher concentrations of lignans, oligolignans, and juvabiones than the adjacent stemwood. Eight fir species were analysed (Abies sibirica, A. lasiocarpa, A. balsamea, A. alba, A. amabilis, A. veitchii, A. sachalinensis, and A. concolor). The amount of lignans could in some knots exceeds 6% (w/w) and the knots generally contained 20–50 times more lignans than the stemwood. However, there were large variations, not only between species but also even between knots in the same tree. Secoisolariciresinol was the predominant lignan in all knots. The lignans occur in free form in the knots and are easily extracted with polar solvents. In addition to the lignans, oligomeric aromatic substances, mainly sesquineo- and dineolignans, and juvabiones were accumulated in the knotwood.

Secoisolariciresinol, but also lariciresinol (Abies alba) and 7-hydroxymatairesinol (A. amabilis), could be extracted in large scale from fir knots at pulp and paper mills. The ready availability of large amounts of lignans and oligolignans now enables research to assess their bioactivity and provide the base for applications in medicine and nutrition, or as natural antioxidants and antimicrobial agents in various technical products.
Evaluation of hydrocarbon emissions from heart- and sapwood of Scots pine using a laboratory-scale wood drier
Authors: Bengtsson Peter , Sanati Mehri
Published: October 2004

The subject of study is the emission of Volatile Organic Compounds (VOC) during the drying of wood. Heartwood and sapwood from Scots pine were dried at different temperatures (50, 70 and 90°C) in a laboratory kiln.

The sampling method, Solid Phase Microextraction was used to collect the different volatile organic compounds during the drying. The gas chromatograph and mass spectrometer was used to identify and quantify the organic matter. The total hydrocarbons were measured with a flame ionization detector. Primarily, different monoterpenes were released during the drying process. 3-carene and α-pinene were most common and were also analytically quantified. The diterpene, pimaral, was found in an estimated large amount in the later stage of the drying process but was not exactly quantified.

Large differences in both release behavior and total amount of released hydrocarbon between heart- and sapwood were obtained.

Emissions of VOC from heartwood were of a magnitude approximately three times higher than that from sapwood.
Effect of pulsating tension-torsion combined loading on fatigue behavior in wood
Authors: Sasaki Yasutoshi , Yamasaki Mariko
Published: October 2004

The effect of cyclic tension-torsion combined loading on the fatigue behavior and stress-strain properties of wood (Japanese cypress) was investigated experimentally. The specimen used in the experiments was a rectangular bar with its major axis in the fiber (longitudinal) direction of wood. Pulsating tension and torsion loadings were respectively applied along and around the longitudinal axis of the specimen. According to the relationships between stress and strain obtained using fatigue tests, the secant modulus of the stress-strain curve changed with an increase in the number of loading cycles, and the differences between the curves for tension and shear were observed. The obtained results of fatigue tests were found to be influenced by the combined stress ratios and the applied stress levels. Bordering on the combined stress state of TB, where tensile and shear stress components were almost equally applied, the trend toward lower stiffness retention was different between tension and shear, and the tensile or torsion failure mode became dominant in the failure mode. The TB state was recognized as a boundary state for both of the stiffness retention and the failure mode. The stiffness retention in the TB state showed a tendency similar to that in the stress state where torsion was dominant regardless of the stress level. On the other hand, the failure mode tended to be tension failure at higher stress levels. Thus, at higher stress levels in the TB state, the effect of the tensile or shear stress component on the fatigue behavior of wood was different between “during the fatigue process” and “the time of failure”. In addition, torsion was dominant for both during the fatigue process and the time of failure at lower stress levels.
Effects of density and microfibril orientation on the vertical variation of low-stiffness wood in radiata pine butt logs
Authors: Xu Ping , Donaldson Lloyd , Walker John , Evans Robert , Downes Geoffrey
Published: October 2004

The roles of density and microfibril angle in causing low stiffness in radiata pine butt logs were studied in detail on a 17-year-old tree. Distributions of these variables were compared with stiffness variations in the vertical direction. Results supported the hypothesis that cell ultrastructure is responsible for the vertical variation in stiffness. The microfibril orientation in tangential wall is considered to be an important factor contributing to wood stiffness because of the smaller microfibril angles compared with radial microfibril angles, and also because of the larger decrease of the microfibril angles with the rapid increase of wood stiffness in vertical direction especially in corewood zone. The microfibrils in the S3 layer fall from over 80° to angles of 54° and 51° for radial and tangential cell walls at the top of the butt log. Further study is needed for fully understanding the characteristics of S3 layers.
High-performance liquid chromatographic analysis of soluble and total oxalate in Ca- and Mg-amended liquid cultures of three wood decay fungi
Authors: Schilling Jonathan S. , Jellison Jody
Published: October 2004

Two brown-rot wood decay fungi,Fomitopsis pinicolaandMeruliporia incrassata, and the white-rot speciesPhanerochaete chrysosporiumwere grown for 4 weeks in liquid culture at 0.35, 0.70, 1.05, and 5.00 mM calcium (Ca) and 1.35 and 2.70 mM magnesium (Mg) concentrations. Soluble and total oxalate levels were quantified using a revised ion-exchange HPLC protocol developed specifically for resolving oxalate and other organic acid anions from medium components. Total oxalate concentrations in brown-rot filtrate were not significantly different among treatments; however, soluble oxalate decreased significantly with increasing Ca concentration. Higher Mg concentrations increased soluble oxalate levels only slightly. There was a significant decrease in medium pH at 5.00 mM Ca for all species, as well as an apparent increase in decarboxylation activity in brown-rot fungi. Total and soluble oxalate levels in the white-rot cultures were generally below detection for all treatments. The results show a significant influence of Ca on soluble oxalate concentrations not seen previously in the brown-rot speciesPostia placenta.
Light Pen Use and Practice Minimize Age and Hand Performance Differences in Pointing Tasks
Authors: Charness Neil , Holley Patricia , Feddon Jeffrey , Jastrzembski Tiffany
Published: October 2004

We contrasted performance with mouse and light pen input devices for younger, middle-aged, and older adults (N = 72) who were experienced mouse users. Participants used both preferred and nonpreferred hands to perform a menu target selection task. The light pen minimized age differences in performance relative to the mouse. Older adults were more lateralized on a handedness test than young adults and were less efficient using their nonpreferred hand. With practice, older adults improved their response time more than other age groups did. The mouse was rated as more acceptable and easier to use than the light pen across trials, despite the performance advantage of the light pen for all age groups. Usability ratings correlated moderately with performance. A benefit-cost analysis indicated that the more efficient light pen might cover its greater initial cost within 11 months for an older adult and within 23 months for a younger adult. Actual or potential applications of this research include advising older adults to persist with practice for new input devices, advising those who must switch to their nonpreferred hand to select a direct positioning device, and providing a methodology for determining the potential payback interval when switching to a faster, though more expensive, input device.
Effect of Job Rotation on Work Demands, Workload, and Recovery of Refuse Truck Drivers and Collectors
Authors: Kuijer P. Paul F. M. , de Vries Wiebe H. K. , van der Beek Allard J. , van Dieën Jaap H. , Visser Bart , Frings-Dresen Monique H. W.
Published: October 2004

Job rotation is often advocated to reduce workload, but its efficacy has seldom been investigated. The aim of this study is to compare the work demands, workload, and recovery among truck driving, refuse collecting, and rotating between these two jobs, between days and during the day. Three teams of 3 employees each participated in this study. Work demands were assessed by systematic observation of tasks and activities. Workload was quantified by means of heart rate, oxygen uptake, subjective ratings, and urinary excretion rates of catecholamines. Recovery was quantified by excretion rates of catecholamines after work. Job rotation between driving and collecting is an effective measure to reduce physical workload as compared with collecting only and to decrease mental workload as compared with driving only. However, job rotation resulted in increased physical workload as compared with driving only. Job rotation did not increase mental workload as compared with collecting only. No effects were seen on recovery. No differences were found between rotating between days and during the day. Actual or potential applications of this research include the recommendation that before job rotation is introduced, its efficacy be determined in terms of well-chosen workload measures because a reduction in work demands does not directly imply a reduction in workload. Therefore, job rotation might be less effective than expected.
Characterizing the Effects of Droplines on Target Acquisition Performance on a 3-D Perspective Display
Authors: Liao Min-Ju , Johnson Walter W.
Published: October 2004

The present study investigated the effects of droplines on target acquisition performance on a 3-D perspective display in which participants were required to move a cursor into a target cube as quickly as possible. Participants' performance and coordination strategies were characterized using both Fitts' law and acquisition patterns of the 3 viewer-centered target display dimensions (azimuth, elevation, and range). Participants' movement trajectories were recorded and used to determine movement times for acquisitions of the entire target and of each of its display dimensions. The goodness of fit of the data to a modified Fitts function varied widely among participants, and the presence of droplines did not have observable impacts on the goodness of fit. However, droplines helped participants navigate via straighter paths and particularly benefited range dimension acquisition. A general preference for visually overlapping the target with the cursor prior to capturing the target was found. Potential applications of this research include the design of interactive 3-D perspective displays in which fast and accurate selection and manipulation of content residing at multiple ranges may be a challenge.
Sonification Supports Eyes-Free Respiratory Monitoring and Task Time-Sharing
Authors: Watson Marcus , Sanderson Penelope
Published: October 2004

Three experiments explored the effectiveness of continuous auditory displays, or sonifications, for conveying information about a simulated anesthetized patient's respiration. Experiment 1 established an effective respiratory sonification. Experiment 2 showed an effect of expertise in the use of respiratory sonification and revealed that some apparent differences in sonification effectiveness could be accounted for by response bias. Experiment 3 showed that sonification helps anesthesiologists to maintain high levels of awareness of the simulated patient's state while performing other tasks more effectively than when relying upon visual monitoring of the simulated patient state. Overall, sonification of patient physiology beyond traditional pulse oximetry appears to be a viable and useful adjunct to visual monitors. Actual and potential applications of this research include monitoring in a wide variety of busy critical care contexts.
Speed-Accuracy Characteristics of Human-Machine Cooperative Manipulation Using Virtual Fixtures With Variable Admittance
Authors: Marayong Panadda , Okamura Allison M.
Published: October 2004

This work explores the effect of virtual fixture admittance on the performance, defined by error and time, of task execution with a human-machine cooperative system. A desired path is obtained using computer vision, and virtual fixtures for assistance in planar path following were implemented on an admittance-controlled robot. The admittance controller uses a velocity gain, so that the speed of the robot is proportional to the force applied by the operator. The level of virtual fixture guidance is determined by the admittance ratio, which is the ratio of the admittance gain of the force components orthogonal to the path to the gain of the force components parallel to the path. In Experiment 1, we found a linear relationship between admittance ratio and performance. In Experiment 2, we examined the effect of admittance ratio on the performance of three tasks: path following, off-path targeting, and obstacle avoidance. An algorithm was developed to select an appropriate admittance ratio based on the nature of the task. Automatic admittance ratio tuning is recommended for next-generation virtual fixtures. Actual or potential applications of this research include surgery, assembly, and manipulation at the macro and micro scales.
Immediate Occlusal Loading the Same Day or the Day After Implant Placement: Comparison of 2 Different Time Frames in Totally Edentulous Lower Jaws
Authors: Testori Tiziano , Del Fabbro Massimo , Galli Fabio , Francetti Luca , Taschieri Silvio , Weinstein Roberto
Published: October 2004

Immediate loading of endosseous implants is becoming a widespread therapeutic procedure for the rehabilitation of patients with edentulous jaws. The purpose of this prospective clinical trial was to evaluate the long-term success rate of endosseous implants placed in the edentulous lower jaw and loaded on either the same day of surgery or the next day. Nineteen patients were enrolled in the study. Eleven patients, accounting for 64 implants, received their provisional prosthesis the same day of implant placement, and 8 patients, accounting for 52 implants, were rehabilitated the day after surgery. All patients were rehabilitated by a hybrid prosthesis supported by 5 to 6 Osseotite implants. Two implants failed in the group of patients who had their implants loaded the same day (96.9% success rate), whereas 1 implant failed in the other group (98.1% success rate). The overall implant success rate was 97.4%. All failures occurred within 2 months of function. No other complication was reported. The mean follow-up for this interim report was 37.8 ± 16.5 months (range 8–65 months). Crestal bone loss was similar to that reported for standard delayed loading protocols. The results of this study suggest that the rehabilitation of the edentulous lower jaw by an immediate occlusally loaded implant-supported hybrid prosthesis is equally successful when loading is applied the same day or the day after implant placement. Immediate loading with 5 to 6 implant-supported prostheses represents a viable alternative treatment to classic delayed loading protocols.
Immediate Functional Load of Mandibular Implant Overdentures: A Surgical and Prosthodontic Rationale of 2 Implant Modalities
Authors: Lozada Jaime L. , Al-Ardah Aladdin J. , Rungcharassaeng Kitichai , Kan Joseph Y. K. , Kleinman Alejandro
Published: October 2004

Classic guidelines in osseointegration for root-form dental implants include a long healing period, during which functional load should be avoided. However, the long healing period might impose an intolerable situation on some patients, especially in the completely edentulous situation. Subperiosteal dental implant guidelines demonstrate that the implant upon insertion can be put into immediate function and be restored with the final prosthesis soon after surgery. Studies on immediately functional loaded implant-supported prostheses in patients who are completely edentulous have been reported, exhibiting high success rates comparable with conventionally loaded implants. This article describes the surgical and prosthodontic procedure for the immediately functional loaded mandibular implant overdentures in 2 different dental implant modalities, as well as its clinical rationale.
A Newly Designed Template Device for Use With the Insertion of Immediately Loaded Implants
Authors: Pontual Marco A. B. , Freire JoséN. O. , Souza Dircilene C. , Ferreira Cimara F. , Bianchini Marco A. , Magini Ricardo S.
Published: October 2004

This article describes a newly designed surgical template that was used to facilitate dental implant placement. The implants were planned to function by loading them immediately. A case report describing the device and the benefits of its use for a patient with an edentulous mandible is presented. Four implants were placed in the anterior region of the mandible to support an immediately fixed prosthesis. Clinical and radiographic analyses were conducted postoperatively to evaluate bone loss and peri-implant soft-tissue healing. The salutary results demonstrated the positive value of this therapeutic approach and presented the advantages of shorter treatment times, fewer patient visits, lower costs, and elimination of secondary surgical procedures.
Mechanism of palladium‐catalyzed reactions: role of chloride ions
Authors: Jutand Anny
Published: October 2004

Chloride ions play a very important role in palladium‐catalyzed reactions. This review illustrates how chloride ions modify: (i) the kinetics of the oxidative addition of aryl triflates, vinyl triflates, allylic acetates to palladium(0) complexes; (ii) the structure of the aryl‐, vinyl‐ or allyl‐palladium(II) complexes, generated in the oxidative addition, by formation of neutral aryl‐, vinyl‐ or η1‐allyl‐palladium(II) chloride complexes respectively, instead of cationic aryl‐, vinyl‐ or (η3‐allyl)palladium(II) complexes; (iii) the mechanism of the second step of the catalytic cycle of the Stille reactions of aryl or vinyl triflates by formation of neutral aryl‐ or vinyl‐ chloride complexes able to react with the nucleophile; and (iv) the mechanism of the second step of the catalytic cycle of the Tsuji–Trost reactions, i.e. the nucleophilic attack on allyl‐palladium(II) complexes (neutral η1‐allyl‐PdCl versus cationic (η3‐allyl)palladium(II) complexes). Copyright © 2004 John Wiley & Sons, Ltd.
A simple and practical protocol for the palladium‐catalyzed cross‐coupling of boronic acids with methyl iodide
Authors: Gooßen Lukas J.
Published: October 2004

A combination of palladium acetate and tri‐1‐naphthylphosphine was found to be a highly efficient catalyst system for the cross‐coupling of arylboronic acids with methyl iodide at room temperature. The new process allows for a convenient introduction of methyl groups into various functionalized arenes under mild conditions. Copyright © 2004 John Wiley & Sons, Ltd.
Developmental toxicity evaluation of sodium thioglycolate administered topically to Sprague–Dawley (CD) rats and New Zealand white rabbits
Authors: Tyl R.W. , Price C.J. , Marr M.C. , Myers C.B. , van Birgelen A.P.J.M. , Jahnke G.D.
Published: October 2004

BACKGROUND: Sodium thioglycolate, which has widespread occupational and consumer exposure to women from cosmetics and hair‐care products, was evaluated for developmental toxicity by topical exposure during the embryonic and fetal periods of pregnancy

METHODS: Timed‐mated Sprague–Dawley rats (25/group) and New Zealand White (NZW) rabbits (24/group) were exposed to sodium thioglycolate in vehicle (95% ethanol:distilled water, 1:1) by unoccluded topical application on gestational days (GD) 6–19 (rats) or 6–29 (rabbits) for 6 hr/day, at 0, 50, 100, or 200 mg/kg body weight/day (rats) and 0, 10, 15, 25, or 65 mg/kg/day (rabbits). At termination (GD 20 rats; GD 30 rabbits), fetuses were examined for external, visceral, and skeletal malformations and variations.

RESULTS: In rats, maternal topical exposure to sodium thioglycolate, at 200 mg/kg/day (the highest dose tested) on GD 6–19, resulted in maternal toxicity, including reduced body weights and weight gain, increased relative water consumption and one death. Treatment‐related increases in feed consumption and changes at the application site occurred at all doses, in the absence of increased body weights or body weight change. Fetal body weights/litter were decreased at 200 mg/kg/day, with no other embryo/fetal toxicity and no treatment‐related teratogenicity in any group. In rabbits, maternal topical exposure to sodium thioglycolate on GD 6–29 resulted in maternal dose‐related toxicity at the dosing site in all groups; no maternal systemic toxicity, embryo/fetal toxicity, or treatment‐related teratogenicity were observed in any group.

CONCLUSIONS: A no observed adverse effect level (NOAEL) was not identified for maternal toxicity in either species with the dosages tested. The developmental toxicity NOAEL was 100 mg/kg/day (rats) and ≥65 mg/kg/day (rabbits; the highest dose tested). The clinical relevance of theses study results is uncertain because no data were available for levels, frequency, or duration of exposures in female workers or end users. Birth Defects Research Part B 68:144–161, 2003. © 2003 Wiley‐Liss, Inc.
Anatomical study of perforator arteries in the distally based radial forearm fasciosubcutaneous flap
Authors: Tiengo Cesare , Macchi Veronica , Porzionato Andrea , Bassetto Francesco , Mazzoleni Franco , De Caro Raffaele
Published: October 2004

We investigated the anatomical vascular basis of the forearm fasciosubcutaneous flap (FSC‐F), fed by the distal perforator arteries of the fascia. This type of flap was proposed, in hand reconstructive surgery, to avoid the disadvantages caused by axial‐pattern reverse radial forearm fasciocutaneous flap, based on ligation and rotation of the radial artery (RA). In eight fresh cadaveric forearms, the RA was injected slowly with acrylic resin and the superficial flexor compartment was dissected. Then the FSC‐F was raised from the lateral margins of the sample to the median RA axis, and the collaterals of the RA (number, interval of origin, and caliber) were evaluated. The fascial branches of RA (mean number ± SD: 20 ± 3) originated mainly from the radial and ulnar sides of the RA. In the distal forearm the vessels were more numerous (mean value = 11.3 vs. 8.9; Student's t‐test, P < 0.05) but smaller in diameter (mean value = 0.45 mm vs. 0.63 mm; Student's t‐test, P < 0.05). The perforator arteries forked in a T‐shape following the main axis of the forearm and anastomosed in the fascial plane, forming longitudinal fan‐shaped arterial chains giving rise to the vascular epifascial network. Histological (hematoxylin‐eosin, azan‐Mallory, Weigert) and immunohistochemical (anti‐von Willebrand factor) study of the FSC‐F at different levels of sampling was also carried out. The epifascial branches of distal sections were smaller in diameter (78.3 ± 35.5 μm) than those of intermediate (105.7 ± 28.7 μm; Newman‐Keuls test, P < 0.01) and proximal (116.8 ± 31.2 μm; Newman‐Keuls test, P < 0.001) sections. Our findings indicate that the perforator arteries and epifascial branches are smaller in the distal forearm, so that during surgical dissection, the safety distance from the radial styloid should take into account that also in the presence of a sufficient number of vessels in the distal forearm their caliber could be inadequate to the hemodynamic request of the flap. Thus, rather than on a theoretic distance from the radial styloid, the length of the flap should be based on an accurate evaluation of the individual vascularization of the forearm case by case. Clin. Anat. 17:636–642, 2004. © 2004 Wiley‐Liss, Inc.
Unusual insertion of the coracobrachialis muscle to the brachial fascia associated with high division of brachial artery
Authors: Ray Bappaditya , Rai Anju Lata , Roy T.S.
Published: October 2004

Anatomical variations of the coracobrachialis muscle (CBM) are common. We detected an abnormal form of the CBM of the left arm during human cadaver dissection. The CBM originated from the tip of the coracoid process of the scapula and divided into muscular and musculo‐aponeurotic bellies. The muscular belly inserted into the middle of the anteromedial surface of the humerus, which is the normal anatomic insertion point of the CBM. The musculo‐aponeurotic belly inserted into the medial intermuscular septum as well as the brachial fascia, creating a tunnel for the passage of the brachial artery. Inside the tunnel, the brachial artery bifurcated into the radial and ulnar arteries. No abnormality of the CBM, the brachial artery, or the median nerve was detected in the contralateral arm. The phylogenic, ontogenic, functional, and clinical importance of this variant muscle is described. Knowledge of such variations is of considerable importance during invasive and non‐invasive investigative procedures or orthopedic, reconstructive, or surgical procedures. Clin. Anat. 17:672–676, 2004. © 2004 Wiley‐Liss, Inc.
Exploratory Studies to Investigate a Linked Prebiotic Origin of RNA and Coded Peptides. 2nd Communication
Authors: Smith James M. , Borsenberger Vinciane , Raftery Jim , Sutherland John D.
Published: October 2004

The potentially prebiotic synthesis of ribo‐nucleotides by stepwise pyrimidine nucleobase assembly on arabinose‐3‐phosphate derivatives has been demonstrated in previous work [1]. Consideration of the provenance of pentose phosphates, by aldolisation or sugar phosphorylation, suggested that 2‐phosphate derivatives might be generated more easily than 3‐phosphate derivatives. In the 2‐phosphate series, nucleobase‐assembly chemistry to give ribo‐nucleotides/nucleic acid can be envisaged from xylo‐configured starting materials. In this paper, the derivation of xylose‐2‐phosphate derivatives by aldol chemistry and attempts to demonstrate subsequent pyrimidine nucleobase assembly are reported.
Adamantylsulfanyl‐ and N‐Adamantylcarboxamido‐Derivatives of Heterocycles and Phenoles: Synthesis, Crystal Structure, Tumor Necrosis Factor‐α Production‐Enhancing Properties, and Theoretical Considerations
Authors: Maurin Jan Krzysztof , Lasek Witold , Górska Agata , Świtaj Tomasz , Jakubowska Anna Beata , Kazimierczuk Zygmunt
Published: October 2004

The synthesis of several adamantylthio heterocycles and S‐adamantylated thiocresols is reported. The attack of the adamantyl cation formed from 1‐adamantan‐1‐ol in refluxing trifluoroacetic acid provides the corresponding adamantylsulfanyl compounds. The use of the adamantyl cation in the Ritter reaction gave the number of N‐adamantylcarboxamide derivatives of heterocyclic and phenolic compounds. Adamantylsulfanyl heterocycles, contrary to N‐adamantylcarboxamido compounds, enhanced the production of tumor necrosis factor α (TNF‐α) in genetically modified murine melanoma cells transduced with the gene for human TNF‐α. The highest activity, comparable to that of the most‐active previously described for 6‐methyl‐2‐[(adamantyl)amino]pyridine, showed 2‐thioadamantyl derivatives of pyridine and 6‐methylpyridine. The crystal structures of carboxamido and sulfanyl analogues of 2‐(1‐adamantylamino)pyridine have been studied, and consecutive quantum‐chemical calculations have been performed. The low TNF‐α production stimulatory activity of N‐adamantylcarboxamido‐pyridine compared to the sulfanyl and amino analogues is postulated to be linked to the conformational rigidity of the former one enhanced by the formation of the intramolecular H‐bond. The comparison of the activity of 2‐(1‐adamantylsulfanyl)‐6‐methylpyridine and (1‐adamantylsulfanyl)‐2‐methylbenzene proved the importance of the ring N‐atom, whereas the differences in activity between bromo and methyl analogues pointed at electronic rather than steric influence of ortho‐substituents on the biological activity.
Synthesis of (2′S)‐ and (2′R)‐2′‐Deoxy‐2′‐[(2‐methoxyethoxy)amino] Pyrimidine Nucleosides and Oligonucleotides
Authors: Zatsepin Timofei S. , Ivanova Yulia M. , Oretskaya Tatiana S.
Published: October 2004

Syntheses of specified 2′‐modified nucleosides were achieved: a) via oximation of the 5′,3′‐blocked 2′‐oxocytidine, followed by reduction, or b) by intramolecular nucleophilic addition of 3′‐(2‐methoxyethoxy)carbamate to the 2′‐position with opening of O2,2′‐anhydrouridine. For the first time, 3′‐phosphoroamidites of these 2′‐modified nucleosides were successfully incorporated into oligonucleotides by solid‐phase synthesis. Incorporation of 2′‐modified nucleotides into oligodeoxyribonucleotides had a negative effect on the duplex Tm values with the DNA or RNA complements. Nevertheless, modified nucleotides have shown good target recognition; the (S)‐isomer binds preferably to RNA and the (R)‐isomer to DNA. Both modified nucleosides significantly increased nuclease resistance of the oligodeoxyribonucleotides.
Understanding Sterol–Membrane Interactions Part I: Hartree–Fock versus DFT Calculations of 13C and 1H NMR Isotropic Chemical Shifts of Sterols in Solution and Analysis of Hydrogen‐Bonding Effects
Authors: Jolibois Franck , Soubias Olivier , Réat Valérie , Milon Alain
Published: October 2004

1H and 13C NMR chemical shifts are exquisitely sensitive probes of the local environment of the corresponding nuclei. Ultimately, direct determination of the chemical shifts of sterols in their membrane environment has the potential to reveal their molecular interactions and dynamics, in particular concerning the hydrogen‐bonding partners of their OH groups. However, this strategy requires an accurate and efficient means to quantify the influence of the various interactions on chemical shielding. Herein the validity of Hartree–Fock and DFT calculations of the 13C and 1H NMR chemical shifts of cholesterol and ergosterol are compared with one another and with experimental chemical shifts measured in solution at 500 MHz. A computational strategy (definition of basis set, simpler molecular models for the sterols themselves and their molecular complexes) is proposed and compared with experimental data in solution. It is shown in particular that the effects of hydrogen bonding with various functional groups (water as a hydrogen‐bond donor and acceptor, acetone) on NMR chemical shifts in CDCl3 solution can be accurately reproduced with this computational approach.
Infrared Spectra of Hydrogen‐Bonded Ionic Crystals: Ab initio Study of Mg(OH)2 and β‐Be(OH)2.
Authors: Ugliengo Piero , Pascale Fabien , Merawa Mohammadou , Labeguerie Pierre , Tosoni Sergio , Dovesi Roberto
Published: October 2004

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Dihydrogen Bonds in Solid BH3NH3
Authors: Morrison Carole A. , Siddick Muhammad M.
Published: October 2004

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Structure, Growth and Optical Properties of Zn0.24Ni0.76(SO4)×7H2O Single Crystal.
Authors: Zhuang Xinxin , Su Genbo , Wang Guofu , Li Guohui , Huang Zixiang
Published: October 2004

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Nd2(SeO3)2 (SeO4)×2H2O — A Mixed‐Valence Compound Containing Selenium in the Oxidation States +IV and +VI.
Authors: Berdonosov P. S. , Schmidt P. , Dityat'yev O. A. , Dolgikh V. A. , Lightfoot P. , Ruck M.
Published: October 2004

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Er2S[SiO4]: An Erbium Sulfide ortho‐Oxosilicate with Unusual Sulfide‐Anion Coordination.
Authors: Hartenbach Ingo , Lauxmann Petra , Schleid Thomas
Published: October 2004

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How Stable Are Inorganic Fullerene‐Like Particles? Thermal Analysis (STA) of Inorganic Fullerene‐Like NbS2, MoS2, and WS2 in Oxidizing and Inert Atmospheres in Comparison with the Bulk Material.
Authors: Schuffenhauer Christoph , Wildermuth Gerhard , Felsche Juergen , Tenne Reshef
Published: October 2004

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A New Mesoporous Manganese Oxide Pillared with Double Layers of Alumina.
Authors: Wang Lianzhou , Ebina Yasuo , Takada Kazunori , Kurashima Keiji , Sasaki Takayoshi
Published: October 2004

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Asymmetric 1,4‐Hydrosilylations of α,β‐Unsaturated Esters.
Authors: Lipshutz Bruce H. , Servesko Jeff M. , Taft Benjamin R.
Published: October 2004

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Preparation of Cyclopropylsilanes from Terminal Alkenes with Organochromium Reagents.
Authors: Takai Kazuhiko , Hirano Masato , Toshikawa Shota
Published: October 2004

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Electrochemical Fluorination of Benzamide and Acetanilide in Anhydrous HF and in Acetonitrile.
Authors: Shainyan B. A. , Danilevich Yu. S. , Grigor'eva A. A. , Chuvashev Yu. A.
Published: October 2004

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New Efficient Method of Alkoxymethyl Etherification of Secondary Alcohols.
Authors: Watanabe Yosuke , Ikemoto Tetsuya
Published: October 2004

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Mercuric Nitrate‐Mediated Deprotection of Oximes, Hydrazones, and Semicarbazones.
Authors: De Surya Kanta
Published: October 2004

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Allyl, Methallyl, Prenyl, and Methylprenyl Ethers as Protected Alcohols: Their Selective Cleavage with Diphenyldisulfone under Neutral Conditions.
Authors: Markovic Dean , Vogel Pierre
Published: October 2004

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Reaction of Silyldihalomethyllithiums with Nitriles: Formation of α‐Keto Acylsilanes via Azirines and 1,3‐Rearrangement of Silyl Group from C to N.
Authors: Yagi Kazunari , Tsuritani Takayuki , Takami Kazuaki , Shinokubo Hiroshi , Oshima Koichiro
Published: October 2004

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Novel β‐Hydroxy‐β‐bis(trifluoromethyl) Imines.
Authors: Barten Jan Alexander , Lork Enno , Roeschenthaler Gerd‐Volker
Published: October 2004

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Ruthenium‐Catalyzed Transformation of 3‐Benzyl But‐1‐ynyl Ethers into 1,3‐Dienes and Benzaldehyde via Transfer Hydrogen.
Authors: Yeh Kuo‐Liang , Liu Bo , Lai Yen‐Ting , Li Chia‐Wen , Liu Rai‐Shung
Published: October 2004

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Cu(I)‐Mediated Reductive Amination of Boronic Acids with Nitroso Aromatics.
Authors: Yu Ying , Srogl Jiri , Liebeskind Lanny S.
Published: October 2004

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A Hierarchy of Aryloxide Deprotection by Boron Tribromide.
Authors: Punna Sreenivas , Meunier Stephane , Finn M. G.
Published: October 2004

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InCl3‐Catalyzed Regioselective Ring‐Opening Reactions of Epoxides to β‐Hydroxy Ethers.
Authors: Kim Byeong Hyo , Piao Fengyu , Lee Eun Joo , Kim Ji Sook , Jun Young Moo , Lee Byung Min
Published: October 2004

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Antituberculous Activity of Some Aryl Semicarbazone Derivatives.
Authors: Sriram Dharmarajan , Yogeeswari Perumal , Thirumurugan Rathinasabapathy
Published: October 2004

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A Simple and Direct Synthesis of Erythro‐β‐amino‐α‐hydroxy Esters from trans‐β‐Phenylglycidic Ester.
Authors: Besbes Rafaa , Ennigrou Mohamed Rached
Published: October 2004

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A Soluble Fluorous Palladium Complex that Promotes Heck Reactions and Can Be Recovered and Reused.
Authors: Curran Dennis P. , Fischer Karin , Moura‐Letts Gustavo
Published: October 2004

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Optimization of the Synthesis of Guanidines from Amines via Nitroguanidines Using 3,5‐Dimethyl‐N‐nitro‐1H‐pyrazole‐1‐carboxamidine.
Authors: Castillo‐Melendez Joel A. , Golding Bernard T.
Published: October 2004

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The Synthesis and Characterization of a Novel Insulin Sensitizing Agent.
Authors: von Geldern Thomas W. , Brun Regina P. , Kalmanovich Masha , Wilcox Denise , Jacobson Peer B.
Published: October 2004

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Reductive Dimerization of Dithianylium Salts and Fluorodesulfuration: A New Synthetic Approach to Tetrafluoroethylene Substructures.
Authors: Kirsch Peer , Lenges Marc , Ruhl Andreas , Sevenard Dmitri V. , Roeschenthaler Gerd‐Volker
Published: October 2004

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Effective Chiral Thiophene Diamine Derivatives in Pd‐Catalyzed Enantioselective Allylic Alkylation.
Authors: Kim Sang‐Han , Lee Eun‐Kyung , Kim Geon‐Joong
Published: October 2004

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Novel Fluorescent pH Sensors Based on Intramolecular Hydrogen Bonding Ability of Naphthalimide.
Authors: Cui Dawei , Qian Xuhong , Liu Fengyu , Zhang Rong
Published: October 2004

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Cationic Planar Chiral Palladium P,S Complexes as Highly Efficient Catalysts in the Enantioselective Ring Opening of Oxa‐ and Azabicyclic Alkenes.
Authors: Cabrera Silvia , Gomez Arrayas Ramon , Carretero Juan C.
Published: October 2004

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β‐Lactam Synthesis by Ugi Reaction of β‐Keto Acids in Aqueous Solution.
Authors: Pirrung Michael C. , Sarma Koushik Das
Published: October 2004

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A Facile Three‐Component One‐Pot Synthesis of Structurally Constrained Tetrahydrofurans that Are t‐RNA Synthetase Inhibitor Analogues.
Authors: Lu Chong‐Dao , Chen Zhi‐Yong , Liu Hui , Hu Wen‐Hao , Mi Ai‐Qiao , Doyle Michael P.
Published: October 2004

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Use of a Modified Leimgruber—Batcho Reaction to Prepare 6‐Chloro‐5‐fluoroindole.
Authors: Bentley Jon M. , Davidson James E. , Dunction Matthew A. J. , Giles Paul R. , Pratt Robert M.
Published: October 2004

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Hexafluoroacetone as Protecting and Activating Reagent: Reactions of Hexafluoroacetone with α‐Keto Acids.
Authors: Spengler Jan , Osipov Sergej N. , Heistracher Elisabeth , Haas Alois , Burger Klaus
Published: October 2004

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Synthesis of Antiinflammatory, Analgesic and COX‐II Inhibitory Activities of Indolylpyrazolines.
Authors: Kumar Ashok , et al. et al.
Published: October 2004

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Synthesis of N,N‐Dimethylpropanediamide and Its Utility for the Preparation of 2‐(Acetamidomethyl)‐4‐aryloxazoles.
Authors: Ragan John A. , Burmaster Michael , Hill Paul D.
Published: October 2004

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Organic Reactions in Aqueous Media: I2‐in‐Water‐Catalyzed Rapid and Chemoselective Oxathioacetalization of Aldehydes under Mild Conditions.
Authors: Bandgar B. P. , Bettigeri Sampada V.
Published: October 2004

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Synthesis and Fungicidal Activity of Fluorine‐Containing Phenylimino‐thiazolidines Derivatives.
Authors: Xu Xiaoyong , Qian Xuhong , Li Zhong , Song Gonghua , Chen Weidong
Published: October 2004

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