bluuebunny/crossref_metadata_2025 huggingface dataset:
CXCR1‐binding chemokines in inflammatory bowel diseases: down‐regulated IL‐8/CXCL8 production by leukocytes in Crohn's disease and selective GCP‐2/CXCL6 expression in inflamed intestinal tissue
Authors: Gijsbers Klara , Van Assche Gert , Joossens Sofie , Struyf Sofie , Proost Paul , Rutgeerts Paul , Geboes Karel , Van Damme Jo
Published: June 2004

Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) that are characterized by chronic intestinal inflammation and a constant influx of leukocytes mediated by pro‐inflammatory cytokines and chemokines. The intestinal expression of the CXCR1‐binding chemokines IL‐8/CXCL8 and GCP‐2/CXCL6 and the participation of immunocompetent cells in IBD were evaluated. IL‐8 production by peripheral blood mononuclear cells (PBMC) from IBD patients, stimulated with endotoxin, plant lectin or double‐stranded RNA, was significantly lowered in patients with CD, but not in UC patients or healthy subjects. The reduced chemokine production by PBMC from IBD patients was both IL‐8 and CD specific, but not inducer dependent. In serum, most chemokines remained undetectable, while the levels of those that were measurable remained unaltered in IBD patients. GCP‐2, but not ENA‐78/CXCL5, nor IL‐8, were highly expressed by endothelial cells in inflamed intestinaltissue of IBD patients. In contrast, stimulated endothelial cell cultures produced more IL‐8 than GCP‐2. The selective GCP‐2 staining of endothelial cells at sites of ulcerations suggests that GCP‐2, despite its low production capacity in vitro, plays a role in IBD that is different from that of structurally (ENA‐78) and functionally (IL‐8) related ELR+ CXC chemokines. Thus, the chemokine network shows complementarity rather than redundancy.
Depending on their maturation state, splenic dendritic cells induce the differentiation of CD4+ T lymphocytes into memory and/or effector cells in vivo
Authors: de Heusch Magali , Oldenhove Guillaume , Urbain Jacques , Thielemans Kris , Maliszewski Charlie , Leo Oberdan , Moser Muriel
Published: June 2004

There is increasing evidence that dendritic cells (DC) display opposite functions in the immune system, as they may induce immunity or tolerance depending on intrinsic and environmental factors. In mice, adoptive transfer of mature DC pulsed extracorporeally with antigen induces the development of antigen‐specific Th1‐ and Th2‐type CD4+ cells. In this work, we compared the adjuvant properties of immature (freshly isolated) and mature (cultured) splenic DC in vivo. Our data show that injection of either cell population induces the clonal expansion of CD4+ T cells but that only mature DC trigger their differentiation into effector cells producing IFN‐γ. In contrast, transfer of immature DC provokes the development of intermediates in the differentiation process, similar to the central memory cells. These observations, together with data in the literature, suggest that DC may induce tolerance, memory, or immunity depending on their maturationstate.
Evolution of thermograph parameters during the oxidation of extra virgin olive oil
Authors: Kanavouras Antonis , Selke Susan
Published: June 2004

The modulated differential scanning calorimetry (M‐DSC) was used as a rapid and effective method to characterize the olive oil at different levels of oxidation. Thermograph parameters have been related to oxidative degradation of the triglycerides. In this study, their relation to the characteristic off‐flavor compounds, correlated to the oxidative degradation of the oil, was also investigated.

Extra virgin olive oil samples were subjected to the following oxidation treatments: a) purged with air using glass washing bottles at two flow rate values, b) heated in a conventional oven at two area/oil mass ratios, and c) heated in a microwave oven also at two area/oil mass ratios. Samples were withdrawn and analyzed at predetermined intervals. Flavor and off‐flavor compounds were isolated using a dynamic thermal stripping apparatus and transferred into a gas chromatograph by using a thermal desorption unit. All oil samples were analyzed by M‐DSC during cooling from 25 °C to −60 °C at 7 °C/min, and heating back to 40 °C at 10 °C/min. High correlation values were obtained between various M‐DSC thermograph parameters and certain volatile compounds. Results showed that M‐DSC could be used as a simple method to indicate compositional changes in olive oil during oxidation.
The impact of antioxidants on biodiesel oxidation stability
Authors: Schober Sigurd , Mittelbach Martin
Published: June 2004

The potential of 11 different synthetic phenolic antioxidants to improve the oxidation stability of biodiesel prepared from different feedstocks was investigated. Measurements of oxidation stability were carried out according to the European biodiesel specifications with a Rancimat instrument at 110 °C. At antioxidant concentrations of 1000 mg/kg, an improvement in oxidation stability could be achieved with all antioxidants tested. Especially the antioxidants DTBHQ, IONOX 220, Vulkanox ZKF, Vulkanox BKF, and Baynox were able to significantly improve the oxidation stability, leading to stabilization factors between 1.89 and 13.07. Variation of antioxidant concentrations between 100 and 1000 mg/kg showed that the efficiency of the antioxidants varied depending on the different types of biodiesel. When used as additives, Baynox showed good effects on rapeseed oil methyl ester (RME) stability, DBHQ on recycled cooking oil methyl ester (RCOME) stability, Vulkanox BKF on distilled RCOME (DRCOME) stability, and IONOX 220 on tallow methyl ester (TME) stability. Evaluation of the influence of the antioxidants on critical biodiesel fuel parameters showed no negative impacts on viscosities, densities, carbon residues, CFPP, and sulphated ash contents of the different biodiesel samples. However, in terms of acid values, a noticeable increase could be observed at antioxidant levels of 1000 mg/kg. At lower antioxidant concentrations, this increase was much lower and the values remained within the required limits.
Comparison of two kinds of pumpkin seed oils obtained by supercritical CO2 extraction
Authors: Wenli Yu , Yaping Zhao , Jingjing Chen , Bo Shu
Published: June 2004

The oils from two kinds of pumpkin seeds, black and white ones, were extracted by supercritical CO2 (SC‐CO2). The technological variables for SC‐CO2 extraction were optimized and the resulting oils were analyzed by GC‐MS. As a result, the optimal conditions for SC‐CO2 extraction were as follows: 25∼30 MPa, 45 °C, SC‐CO2 flow rate of 30∼40 kg/h. The main compounds in the resulting oils were 9,12‐octadecadienoic acid, 9‐octadecenoic acid, stearic acid, palmitic acid for both types of pumpkin seeds, however, the black seed oil contains more unsaturated fatty acids (UFA) than the white seed oil. On the other hand, some compounds including heptadecanoic acid (0.27%), tetracosanic acid (0.1%), 9‐dodecaenoic acid (0.45%) and pentadecenoic acid (0.05%) were found in white seed oil but not in black seed oil; while eicosanic acid (0.05%), 11,14‐eicosadienoic acid (0.2%), 11‐octadecenoic acid (0.06%), 7‐hexadecenoic acid (0.02%) and 1,12‐tridecadiene (0.02%) were only found in black seed oil.
Loss of heterozygosity on chromosome 6 in HPV‐16 positive cervical carcinomas carrying the DRB1*1501‐DQB1*0602 haplotype
Authors: Arias‐Pulido Hugo , Joste Nancy , Wheeler Cosette M.
Published: June 2004

High‐risk human papillomaviruses (HPVs), specifically HPV‐16 and ‐18, have been associated with the development of carcinoma in situ (CIS) and of invasive cervical cancer (CC). However, only a small fraction of HPV‐infected women will show signs of disease progression, suggesting that other factors in the carcinogenic pathway are needed. We previously demonstrated that human leukocyte antigen (HLA) DRB1*1501‐DQB1*0602 (high risk) was associated with the development of CIS and CC tumors in HPV‐16‐positive patients. To characterize the molecular changes that could be relevant to tumor progression, we compared the extent of loss of heterozygosity (LOH) on chromosome 6 in HPV‐16‐positive CIS patients who were carriers of high‐risk and neutral HLA haplotypes. CIS and CC cases demonstrated similar LOH patterns. A wide range of LOH frequencies was found at 6p (10–53%) and 6q (5–28%) in CIS cases, suggesting that LOH is an early event in the carcinogenic process. A comparative analysis of LOH frequencies in the high‐risk versus the neutral HLA haplotypes showed a statistically significant difference in the extent of LOH at 6p24–p25 (58.6% versus 25.8%; P = 0.018) and at 6p21.3 (79.3% versus 35.5%; P = 0.001), a region that contains the HLA complex. LOH at this region could affect genes encoding HLA class I–II molecules, as well as factors responsible for the assembly, transport, and stable expression of HLA molecules. These losses may be a reflection of both an abnormal immune response and a general genome‐wide instability resulting from virus persistence. © 2004 Wiley‐Liss, Inc.
Follicular variant of papillary thyroid carcinoma: Genome‐wide appraisal of a controversial entity
Authors: Wreesmann Volkert B. , Ghossein Ronald A. , Hezel Michael , Banerjee Debenranrath , Shaha Ashok R. , Tuttle R. Michael , Shah Jatin P. , Rao Pulivarthi H. , Singh Bhuvanesh
Published: June 2004

The majority of thyroid tumors are classified as papillary (papillary thyroid carcinomas; PTCs) or follicular neoplasms (follicular thyroid adenomas and carcinomas; FTA/FTC) based on nuclear features and the cellular growth pattern. However, classification of the follicular variant of papillary thyroid carcinoma (FVPTC) remains an issue of debate. These tumors contain a predominantly follicular growth pattern but display nuclear features and overall clinical behavior consistent with PTC. In this study, we used comparative genomic hybridization (CGH) to compare the global chromosomal aberrations in FVPTC to the PTC of classical variant (classical PTC) and FTA/FTC. In addition, we assessed the presence of peroxisome proliferator‐activated receptor‐gamma (PPARG) alteration, a genetic event specific to FTA/FTC, using Southern blot and immunohistochemistry analyses. In sharp contrast to the findings in classical PTC (4% of cases), CGH analysis demonstrated that both FVPTC (59% of cases) and FTA/FTC (36% of cases) were commonly characterized by aneuploidy (P = 0.0002). Moreover, the pattern of chromosomal aberrations (gains at chromosome arms 2q, 4q, 5q, 6q, 8q, and 13q and deletions at 1p, 9q, 16q, 17q, 19q, and 22q) in the follicular variant of PTC closely resembled that of FTA/FTC. Aberrations in PPARG were uniquely detected in FVPTC and FTA/FTC. Our findings suggest a stronger relationship between the FVPTC and FTA/FTC than previously appreciated and support further consideration of the current classification of thyroid neoplasms. © 2004 Wiley‐Liss, Inc.
Phosphorus heterocycles from 2‐(2‐aminophenyl)‐1H‐benzimidazole
Authors: Hernández‐Díaz Julio , Flores‐Parra Angelina , Contreras Rosalinda
Published: May 2004

We report the syntheses of unsaturated six‐membered heterocycles bearing tri‐, tetra‐, and pentacoordinated phosphorus atoms derived from 2‐(2‐aminophenyl)‐1H‐benzimidazol (1). The presence of three different N–H protons allowed to prepare different compounds by selective substitution. Molecules with two (endo and exocyclic) phosphorus atoms were prepared. The free anilinic proton is the most reactive to substitution reactions, followed by the benzimidazolic, and then the anilinic proton involved in the hydrogen bond. Substitution of the exo‐anilinic proton of 1 by Ph2PCl leads a precursor with a hydrogen bond forming a six‐membered ring, which could be substituted by other groups giving more complex molecules. A pentacoordinated phosphorus compound was obtained after oxidative addition of 3,5‐di‐tert‐butyl‐1,2‐benzoquinone to P(III) heterocycle. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:321–332, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20022
Evolutional background for humanizing technology
Authors: Tytyk Edwin
Published: May 2004

The main aim of the article is to show the evolution of the human approach to work and technology in various developmental periods of technological civilization, and hence to stress the need to initiate conscious and purposeful actions targeted at humanizing technology in modern days. An integral part of engineering knowledge must also be knowledge about humans as users of technological products. Ignoring this part will definitely incur economic and cultural losses. To this effect, a new human‐centered paradigm of evaluating technology was developed. As a relatively young and interdisciplinary branch of science, ergonomics offers both methodological and scientific support for humanization of engineering actions in the field of theory and practice of design, performance, and management. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 307–319, 2004.
Development of safety engineering curricula in the Gulf cooperative countries to meet local manufacturing needs
Authors: Alhemood Ali
Published: May 2004

This article documents the need to establish a safety engineering management program in the Arabian Gulf Region, particularly in the Gulf Cooperative Countries (GCCs)—Kuwait, Saudi Arabia, United Arab Emirates, Bahrain, Qatar, and Oman. Freidman's nonparametric statistical analysis of variance was used to analyze ranks of preferences for safety engineering graduate degrees and programs in the 6 GCCs. On the basis of the findings, manufacturing companies in different countries prefer distinctive safety engineering systems (χ2 = 31.72, df = 5, p = < .05). © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 321–326, 2004.
ERP—Enterprise Resource Planning: A cost‐based business case and implementation assessment
Authors: Han S. W.
Published: May 2004

This article provides the key factors that are critical to the successful implementation of enterprise resource planning (ERP). It reports the results of a study carried out to assess a number of different ERP implementations in different organizations. A case study method of investigation was used, and the experiences of five manufacturing companies were documented. Also, this study explores and proposes an ERP system selection process and a cost‐based business case approach. The critical factors in the adoption of ERP are identified as learning from the experiences of others, appointing a process innovator, establishing committees and project teams, training and providing technical support for the users, and implementing appropriate changes to the organizational structure and managerial responsibilities. For more effective ERP implementations, we advise building a supportive culture and environment with a strong emphasis on human and organizational aspects. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 239–256, 2004.
Immunocytochemically defined interneuron populations in the hippocampus of mouse strains used in transgenic technology
Authors: Mátyás Ferenc , Freund Tamás F. , Gulyás Attila I.
Published: May 2004

Transgenic mice are overtaking the role of model animals in neuroscience. They are used in developmental, anatomical, and physiological as well as experimental neurology. However, most results on the organization of the nervous system derive from the rat. The rat hippocampus and its neuronal elements have been thoroughly investigated, revealing remarkable functional and morphological diversity and specificity among hippocampal interneurons. Our aim was to examine the properties of distinct hippocampal interneuron populations, i.e., those immunoreactive for calcium‐binding proteins (parvalbumin, calbindin, and calretinin), neuropeptides (cholecystokinin, neuropeptide Y, somatostatin, vasoactive intestinal polypeptide), and certain receptors (metabotropic glutamate receptor 1α, cannabinoid receptor type 1) in four strains of mice widely used in transgenic technology, and to compare their properties to those in the rat. Our data indicate that the distribution as well as the dendritic and axonal arborization of mouse interneurons immunoreactive for the different markers was identical in the examined mouse strains, and in most respects are similar to the features found in the rat. The postsynaptic targets of neurons terminating in the perisomatic (parvalbumin), proximal (calbindin), and distal (somatostatin) dendritic region, as well as on other interneurons (calretinin), also matched those found in the rat. However, a few significant differences could also be observed between the two species in addition to the already described immunoreactivity of mossy cells for calretinin: the absence of spiny calretinin‐immunoreactive interneurons in the CA3 region, sparse contacts between calretinin‐immunoreactive interneurons, and the axon staining for somatostatin and neuropil labeling for cholecystokinin. We can conclude that the morphofunctional classification of interneurons established in the rat is largely valid for mouse strains used in transgenic procedures. © 2004 Wiley‐Liss, Inc.
Magnetic fields in the human hippocampal area evoked by a somatosensory oddball task
Authors: Hamada Yasukazu , Sugino Kimihiko , Kado Hisashi , Suzuki Ryoji
Published: May 2004

We recorded neuromagnetic fields evoked by a somatosensory oddball task requiring subjects to discriminate target stimuli from nontarget stimuli, which are different in stimulation intensity, with a mental count of the target stimuli. A whole head type 80‐channel magnetoencephalography (MEG) system with a 50‐mm baseline gradiometer array was used. Targets and nontargets were somatosensory stimuli with an electrical current intensity of twice and three times the sensory threshold, respectively. The source current locations of the evoked magnetic fields in three dimensions and the equivalent current dipole (ECD) moments were calculated by using a single dipole model, assuming the brain as a sphere. In 28 of 63 recording sessions for 7 subjects, the loci of neuronal activities were observed in the left and/or right hippocampal areas. The latency of left hippocampal activity (293 ± 49 ms) was significantly shorter than that of the right (333 ± 45 ms) (P = 0.027, non‐paired t‐test). In view of previous studies that have shown the time window of sensory integration as ∼200–300 ms, sensory information may be transferred to hippocampal areas following sensory integration. © 2004 Wiley‐Liss, Inc.
Glutamatergic synaptic transmission participates in generating the hippocampal EEG
Authors: Leung L. Stan , Shen Bixia
Published: May 2004

The participation of ionotropic glutamatergic synapses in the generation of hippocampal electroencephalography (EEG) of behaving rats has not been systematically studied. In this study, field potentials in hippocampal CA1 were recorded following injection of N‐methyl‐D‐aspartate (NMDA) and α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor antagonists, or vehicle control, either into the lateral ventricles or directly into the hippocampus or the medial septum. Intraventricular (i.c.v.) AMPA receptor antagonist 6,7‐dinitroquinoxaline‐2,3,dione (DNQX, 5–10 μg) decreased the commissural evoked potential and the amplitude of the hippocampal EEG, including the theta rhythm. Theta frequency was decreased by 10 μg, but not 5 μg DNQX i.c.v. Unilateral intrahippocampal injection of DNQX (5 μg) only decreased the amplitude, but not the frequency, of the theta rhythm near the site of injection, without affecting theta amplitude or frequency at the opposite hippocampus. Other than theta, the large irregular activity (with a delta frequency peak at 1–2 Hz) and gamma EEG (30–100 Hz) were also decreased by i.c.v. and intrahippocampal injections of DNQX. Intrahippocampal injection of NMDA receptor antagonist D‐2‐amino‐5‐phosphonovaleric acid (D‐APV, 2.5 μg) decreased the amplitude of the theta rhythm and, less consistently, the gamma EEG. The frequency of the theta rhythm and the peak of the commissural evoked potential were not significantly affected by intrahippocampal D‐APV injection. Medial septal injections of D‐APV or D,L‐APV (2.24 μg in 0.4 μl), but not DNQX (10 μg in 0.4 μl), decreased the amplitude of the hippocampal theta significantly, but theta frequency was not significantly affected. It is concluded that both NMDA and AMPA receptors in the hippocampus are involved in generating the amplitude of the hippocampal EEG of theta and gamma frequencies, while NMDA receptors in the medial septum are involved in controlling the amplitude of theta and gamma EEG in the hippocampus. Excitatory glutamatergic synaptic currents, activated by afferents from the entorhinal cortex and CA3, are suggested to participate in hippocampal EEG activities. © 2004 Wiley‐Liss, Inc.
Development of biodegradable poly(propylene fumarate)/poly(lactic‐co‐glycolic acid) blend microspheres. II. Controlled drug release and microsphere degradation
Authors: Kempen Diederik H. R. , Lu Lichun , Zhu Xun , Kim Choll , Jabbari Esmaiel , Dhert Wouter J. A. , Currier Bradford L. , Yaszemski Michael J.
Published: June 2004

This article describes the effects of six processing parameters on the release kinetics of a model drug Texas red dextran (TRD) from poly(propylene fumarate)/poly(lactic‐co‐glycolic acid) (PPF/PLGA) blend microspheres as well as the degradation of these microspheres. The microspheres were fabricated using a double emulsion‐solvent extraction technique in which the following six parameters were varied: PPF/PLGA ratio, polymer viscosity, vortex speed during emulsification, amount of internal aqueous phase, use of poly(vinyl alcohol) in the internal aqueous phase, and poly(vinyl alcohol) concentration in the external aqueous phase. We have previously characterized these microspheres in terms of microsphere morphology, size distribution, and TRD entrapment efficiency. In this work, the TRD release profiles in phosphate‐buffered saline were determined and all formulations showed an initial burst release in the first 2 days followed by a decreased sustained release over a 38‐day period. The initial burst release varied from 5.1 (±1.1) to 67.7 (±3.4)% of the entrapped TRD, and was affected most by the viscosity of the polymer solution used for microsphere fabrication. The sustained release between day 2 and day 38 ranged from 7.9 (±0.8) to 27.2 (±3.1)% of the entrapped TRD. During 11 weeks of in vitro degradation, the mass of the microspheres remained relatively constant for the first 3 weeks after which it decreased dramatically, whereas the molecular weight of the polymers decreased immediately upon placement in phosphate‐buffered saline. Increasing the PPF content in the PPF/PLGA blend resulted in slower microsphere degradation. Overall, this study provides further understanding of the effects of various processing parameters on the release kinetics from PPF/PLGA blend microspheres thus allowing modulation of drug release to achieve a wide spectrum of release profiles. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 293–302, 2004
Fatigue and damage tolerance of Y‐TZP ceramics in layered biomechanical systems
Authors: Zhang Yu , Pajares Antonia , Lawn Brian R.
Published: June 2004

The fatigue properties of fine‐grain Y‐TZP in cyclic flexural testing are studied. Comparative tests on a coarser‐grain alumina provide a baseline control. A bilayer configuration with ceramic plates bonded to a compliant polymeric substrate and loaded with concentrated forces at the top surfaces, simulating basic layer structures in dental crowns and hip replacement prostheses, is used as a basic test specimen. Critical times to initiate radial crack failure at the ceramic undersurfaces at prescribed maximum surface loads are measured for Y‐TZP with as‐polished surfaces, mechanically predamaged undersurfaces, and after a thermal aging treatment. No differences in critical failure conditions are observed between monotonic and cyclic loading on as‐polished surfaces, or between as‐polished and mechanically damaged surfaces in monotonic loading, consistent with fatigue controlled by slow crack growth. However, the data for mechanically damaged and aged specimens show substantial declines in sustainable stresses and times to failure in cyclic loading, indicating an augmenting role of mechanical and thermal processes in certain instances. In all cases, however, the sustainable stresses in the Y‐TZP remain higher than that of the alumina, suggesting that with proper measures to avoid inherent structural instabilities, Y‐TZP could provide superior performance in biomechanical applications. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 71B: 166–171, 2004
Prediction of resorption rates for composite polylactide/hydroxylapatite internal fixation devices based on initial degradation profiles
Authors: Hile David D. , Doherty Stephen A. , Trantolo Debra J.
Published: June 2004

Mechanical and physicochemical outcomes were used to predict the resorption rate of polylactide‐based internal fixation devices with and without incorporation of an osteoconductive buffer. Devices were degraded in vitro for 1 year. Addition of an osteoconductive buffer to a resorbable polymer internal fixation device controlled the rate of acid generation resulting from polymer hydrolysis. The pH of the physiological buffer remained neutral when it was exposed to the buffered screw, whereas the pH decreased to approximately 3.0 for the polylactide device. Neutralizaton of the acids generated during polymer hydrolysis increased the projected resorption time of the buffered device to 104 weeks in comparison to 71 weeks for a similar screw made from polylactide. In addition, the buffered device retained a higher percentage of its initial flexural strength throughout the course of degradation than the polylactide screw. The flexural strength of the polylactide screw decreased 20% during the first 4 weeks of polymer degradation, whereas the buffered device maintained its initial mechanical properties through 16 weeks of degradation. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 71B: 201–205, 2004
Hemolymph‐dependent and ‐independent responses in Drosophila immune tissue
Authors: Bettencourt Raul , Asha H. , Dearolf Charles , Ip Y. Tony
Published: June 2004

Insects possess an antimicrobial defense response that is similar to the mammalian innate immune response. The innate immune system is designed to recognize conserved components of microorganisms called pathogen‐associated molecular patterns (PAMPs). How host receptors detect PAMPs and transmit the signals to mount the immune response is being elucidated. Using GFP‐Dorsal, ‐Dif, and ‐Relish reporter proteins in ex vivo assays, we demonstrate that Drosophila fat bodies, a major immune tissue, have both hemolymph‐dependent and ‐independent responses. Microbial preparations such as lipoteichoic acid (LTA) and peptidoglycan (PGN) can stimulate some responses from dissected and rinsed larval fat bodies. Therefore, at least some aspects of recognition can occur on fat body cell surfaces, bypassing the requirement of hemolymph. Our results also show that supernatants from bacterial cultures can stimulate the nuclear translocation of Dorsal in dissected fat bodies, but this stimulation is strictly hemolymph‐dependent. Various biochemical assays suggest that the factors from bacterial supernatants that stimulate the hemolymph‐dependent nuclear translocation are likely made up of proteins. We further show that Dorsal mutant larvae have much lower phenoloxidase activity, consistent with a more important role of Dorsal in innate immunity than previously shown. © 2004 Wiley‐Liss, Inc.
A self‐applied, Internet‐based intervention for fear of public speaking
Authors: Botella Cristina , Hofmann Stefan G. , Moscovitch David A.
Published: June 2004

The aim of this article is to introduce, illustrate, and present effectiveness data on a new telepsychology program for the treatment of fear of public speaking. The Talk to Me program is an Internet‐based self‐applied intervention that has several components, including a diagnostic assessment, a structured treatment, and an outcome protocol that evaluates treatment efficacy in a continuous manner. We describe the characteristics of the program and present a case study. Results demonstrated a significant decrease in levels of fear and avoidance related to speaking in public. © 2004 Wiley Periodicals, Inc. J Clin Psychol/In Session.
Etiology and treatment of social anxiety: A commentary
Authors: Bitran Stella , Barlow David H.
Published: June 2004

Substantial advances in our understanding of the etiology and treatment of performance anxiety have occurred during the past decade. It has become clear that the development of efficient and effective treatments cannot be divorced from knowledge of the specific form of psychopathology being treated and that treatments must be tailored to this psychopathology. After describing a current model of the etiology of performance anxiety and social phobia, this commentary notes the common factors present across the rich and diverse set of articles in this issue describing treatments from different approaches and different theoretical orientations. To the extent that these common factors are important mechanisms of action, it is possible that the future will introduce more unified and more effective, efficient, and theoretically informed treatment for performance anxiety as well as the potential for preventive techniques. © 2004 Wiley Periodicals, Inc. J Clin Psychol/In Session.
An investigation into the use of Raman microscopy for the detection of labelled compounds in living human cells
Authors: Kuhnert Nikolai , Thumser Alfred
Published: June 2004

We report on the first detection of vibrationally labelled compounds by Raman micro‐spectroscopy in living cells and demonstrate the feasibility of this technique for bioanalysis. Copyright © 2004 John Wiley & Sons, Ltd.
Ermittlung des Spannungszustandes von Böden aus Werten des Eindringwiderstandes von Sonden
Authors: Hartge Karl Heinrich , Bachmann Jörg
Published: June 2004

Mit handbetriebenen Drucksonden gemessene Eindringwiderstände (EW) sind die einzigen Festigkeitsparameter, die mit geringem apparativem Aufwand vor Ort sofort verfügbar sind. Diesem Vorteil steht die unzulängliche Auswertung als Nachteil gegenüber. Daher wird eine Möglichkeit beschrieben, die Messwerte im Rahmen der Spannungsverteilung im Boden zu interpretieren und dadurch Aussagen über den momentanen Vorverdichtungszustand dieses Bodens zu machen. Hierfür wird dem EW die horizontale Spannungskomponente (σx) zugeordnet und die dazugehörige vertikale (σz) mittels einer Hilfskonstruktion bestimmt. Hierfür wird für die unterste mit der Sonde erreichte Tiefe der hydrostatische Spannungszustand (σhydr) angenommen. In dem Koordinatensystem mit EW als Abszisse und der Tiefe im Boden als Ordinate wird die hydrostatische Spannungssituation an der Bodenoberfläche als Nullpunkt gesetzt. Für den Verlauf der hydrostatischen Spannungssituation zwischen diesen Endpunkten wird eine Gerade als Näherung genommen. Die Relation zwischen dem Messwert (EW) und dem wie beschrieben bestimmten Wert für die hydrostatische Komponente lässt sich als eine dem Ruhedruckkoeffizienten analoge Zahl (KOE) darstellen. An Beispielen wird gezeigt, dass KOE ≅ 1 für normalverdichtete Situationen, wie Waldböden und durch Tiefumbruch meliorierte Flächen, beträgt und sich von überverdichteten Standorten wie Äckern unterscheiden lässt (KOE > 2). Das Ausmaß der so erhaltenen Überverdichtung erlaubt eine Näherungsberechnung der Zusatzbelastung, die der Boden im Moment der EW‐Messung ohne plastische Verformung tragen kann.
Consequences of sodium exclusion for the osmotic potential in the rhizosphere – Comparison of two maize cultivars differing in Na+ uptake
Authors: Vetterlein Doris , Kuhn Katharina , Schubert Sven , Jahn Reinhold
Published: June 2004

According to the biphasic model of growth response to salinity, growth is first reduced by a decrease in the soil osmotic potential (Ψo), i.e., growth reduction is an effect of salt outside rather than inside the plant, and genotypes differing in salt resistance respond identically in this first phase. However, if genotypes differ in Na+ uptake as it has been described for the two maize cultivars Pioneer 3906 and Across 8023, this should result in differences in Na+ concentrations in the rhizosphere soil solution and thus in the concentration of salt outside the plant. It was the aim of the present investigation to test this hypothesis and to investigate the effect of such potential differences in soil Ψo caused by Na+ exclusion on plant water relations. Sodium exclusion at the root surface of intact plants growing in soil was investigated by sampling soil solution from the rhizosphere of two maize cultivars (Across 8023, Pioneer 3906). Plants were grown in a model system, consisting of a root compartment separated from the bulk soil compartment by a nylon net (30 μm mesh size), which enabled independent measurements of the change of soil solution composition and soil water content with increasing distance from the root surface (nylon net). Across 8023 accumulated higher amounts of sodium in the shoot compared to the excluder (Pioneer 3906). The lower Na+ uptake in the excluder was partly compensated by higher K+ uptake. Pioneer 3906 not only excluded sodium from the shoot but also restricted sodium uptake more efficiently from roots relative to Across 8023. This was reflected by higher Na+ concentrations in the rhizosphere soil solution of the excluder 34 days after planting (DAP). The difference in Na+ concentration in rhizosphere soil solution between cultivars was neither due to differences in transpiration and thus in mass flow, nor due to differences in actual soil water content. As the lower Na+ uptake of the excluder (Pioneer 3906) was only partly compensated by increased uptake of K+, soil Ψo in the rhizosphere of the excluder was more negative compared to Across 8023. However, no significant negative effect of decreased soil Ψo on plant water relations (transpiration rate, leaf Ψo, leaf water potential, leaf area) could be detected. This may be explained by the fact that significant differences in soil Ψo between the two cultivars occurred only towards the end of the experiment (27 DAP, 34 DAP).
Nitrate leaching in forest soils: an analysis of long‐term monitoring sites in Germany
Authors: Borken Werner , Matzner Egbert
Published: June 2004

Elevated atmospheric inputs of NH4+ and NO3– have caused N saturation of many forest ecosystems in Central Europe, but the fate of deposited N that is not bounded by trees remains largely unknown. It is expected that an increase of NO3– leaching from forest soils may harm the quality of groundwater in many regions. The objective of this study was to analyze the input and output of NH4+ and NO3– at 57 sites with mature forest stands in Germany. These long‐term study sites are part of the European Level II program and comprise 17 beech, 14 spruce, 17 pine, and 9 oak stands. The chloride balance method was used to calculate seepage fluxes and inorganic N leaching below the rooting zone for the period from 1996 to 2001. Nitrogen input by throughfall was significantly different among most forest types, and was in the order: spruce > beech/oak > pine. These differences can be largely explained by the amount of precipitation and, thus, it mirrors the regional and climatic distribution of these forest types in Germany. Mean long‐term N output with seepage was log‐normal distributed, and ranged between 0 and 26.5 kg N ha–1 yr–1, whereby 29 % of the sites released more than 5 kg N ha–1 yr –1. Leaching of inorganic N was only significantly lower in the pine stands (P < 0.05) compared with leaching rates of the spruce stands. Median N output : input ratio ranged between 0.04 and 0.11 for the beech, oak, and pine stands, while the input : output ratio of the spruce stands was 0.24, suggesting a higher risk of NO3– leaching in spruce forests. Following log‐transformation of the data, N input explained 38 % of the variance in N output. The stratification of the data by the C : N ratio of the O horizon or the top mineral soil revealed that forests soils with a C : N ratio < 25 released significantly more NO3– (median of 4.6 kg N ha–1 yr–1) than forests with a C : N ratio > 25 (median of 0.8 kg N ha–1 yr–1). The stratification improved the correlation between N input and N output for sites with C : N ratios < 25 (r2 = 0.47) while the correlation for sites with C : N ratios > 25 was weaker (r = 0.21) compared with the complete data set. Our results suggest that NO3– leaching may increase in soils with wide C : N ratios when N deposition remains on a high level and that the potential to store inorganic N decreases with C : N ratios in the O horizons becoming more narrow.
Stress corrosion cracking of explosion welded steel‐aluminum joints
Authors: Czechowski M.
Published: June 2004

The article presents the test results of stress corrosion resistance of explosion welded steel‐aluminum elements. The tests were carried out by means of the slow strain rate test (10−6 s−1) in air and artificial sea water. The following parameters were measured: tensile strength, time‐to‐failure and destructive energy. The tested explosion welded joints show susceptibility to degradation of properties in the corrosive environment. Galvanic corrosion is the main reason of degradation of the measured values. Another mechanism of explosion welded joints' destruction was found in air and artificial sea water. The tests of the explosion welded elements in the fast flow of sea water showed substantial galvanic corrosion.
Influence of Surface Carbon Deposition on the Bulk Crystallization of Isotactic Polypropylene
Authors: Liu Jichun , Li Huihui , Duan Yongxin , Jiang Shidong , Miao Zhenjiang , Wang Jijun , Yan Shouke
Published: June 2004

Summary: The effect of a surface‐vacuum‐evaporated ultrathin carbon layer on the bulk crystallization behavior of isotactic polypropylene (iPP) films was investigated by means of polarized optical microscopy, differential scanning calorimetry (DSC), and wide‐angle X‐ray diffraction. Results obtained from both isothermal crystallization and constant cooling experiments indicate that surface carbon deposition on an iPP film can remarkably increase the crystallization ability of it during the melt recrystallization process. Optical microscopy observations show that the melt recrystallization of iPP with a carbon coating starts about 10 °C earlier than the pure iPP during a re‐cooling process of 1 °C · min−1. Under isothermal crystallization conditions, a much shorter induction period for nucleation is required for the carbon‐coated iPP than the non‐carbon‐coated one. The wide‐angle X‐ray diffraction and DSC analyses further demonstrate a crystallinity increment of the carbon‐coated iPP with respect to its non‐carbon‐coated counterpart. This clearly indicates that the strong influence of the interfacial interaction between the vacuum‐evaporated carbon and the iPP film on its bulk crystallization can be extended deep into the bulk material.

An OM micrograph of a hot‐pressed partially carbon‐coated (top half) iPP film.

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An OM micrograph of a hot‐pressed partially carbon‐coated (top half) iPP film.
Novel Carbazole‐Based Ladder‐Type Polymers for Electronic Applications
Authors: Dierschke Frank , Grimsdale Andrew C. , Müllen Klaus
Published: May 2004

Summary: New carbazole‐based ladder‐polymers have been prepared utilising a 3,6‐diacyl‐2,7‐dibromocarbazole building block 4. Suzuki polycondensation of 4 with carbazole‐2,7‐diboronic acid followed by addition of methyl lithium and ring closure with boron trifluoride gave ladder‐polymers 9 with all methine bridges, analogous to ladder‐type poly(para‐phenylene). In very dilute solution, these polymers show blue‐green fluorescence similar to that from the corresponding LPPP. At higher concentrations, a broader red‐shifted emission is seen which suggests that the chains are aggregating in solution. Homopolymerisation of 4 followed by condensation of the carbonyls with boron sulfide produced a novel ladder‐type structure 13 with alternating five‐ and six‐membered rings. This ladder‐polymer displays bright yellow‐green fluorescence. Cyclic voltammetry indicated that these materials have HOMO energy levels comparable to the work function of ITO, making them good candidates for use as hole accepting emissive materials for LEDs.

The ladder polymers synthesised.

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The ladder polymers synthesised.
Syndiospecific Homopolymerisation of Higher 1‐Alkenes with Two Different Bridged [(RPh)2C(Cp)(2,7‐tert‐BuFlu)]ZrCl2 Catalysts
Authors: Hoff Matthias , Kaminsky Walter
Published: May 2004

Summary: Syndiotactic polymers of 1‐pentene, 1‐hexene and 1‐octene were obtained with the CS‐symmetric metallocene catalysts [Ph2C(Cp)(2,7‐tert‐Bu2Flu]ZrCl2 and [(4‐MePh)2C(Cp)(2,7‐tert‐Bu2Flu)]ZrCl2, which have already been proven to give high molar masses and excellent tacticities in propene polymerisation. The monomers were polymerised in bulk and in solution processes at temperatures between 0 and 60 °C using methylaluminoxane as a cocatalyst. The effects on catalyst activity as well as on polymer microstructure and molar mass were determined. Polymers with high syndiotacticities and molar masses (up to 550 000 g · mol−1 in the 1‐octene polymerisation) compared to other metallocenes were obtained.

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Diblock Copolymers with Azobenzene Side‐Groups and Polystyrene Matrix: Synthesis, Characterization and Photoaddressing
Authors: Frenz Carsten , Fuchs Andreas , Schmidt Hans‐Werner , Theissen Ulrich , Haarer Dietrich
Published: June 2004

Summary: Diblock copolymers with a photoaddressable dispersed phase containing p‐methoxy substituted azobenzene side groups and a polystyrene matrix were synthesized and characterized. The block copolymers were prepared by a sequential living anionic polymerization of butadiene and styrene. The poly(1,2‐butadiene) segment was hydroborated and the hydroxy‐functions converted by a polymeranalogous reaction with the azo chromophore as side groups. The block copolymers were synthesized with different compositions by varying the length of the polystyrene segment and the length of the functionalized segment in order to obtain different morphologies. In this paper, for the first time a comparison of the cis‐trans photo‐isomerization behavior and photoaddressing with respect to different morphologies of the block copolymers is presented. To complete the comparison, the corresponding homopolymer and a statistical copolymer were also synthesized and investigated. A different photoaddressing behavior between homopolymer, statistical copolymer and the block copolymers was observed. One principal difference and advantage for photo addressable block copolymers is the lack of a formation of surface gratings which occurs in homopolymers and statistical copolymers.

TEM of a poly(1,2‐butadiene)‐block‐polystyrene copolymer containing azobenzene side‐groups.

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TEM of a poly(1,2‐butadiene)‐block‐polystyrene copolymer containing azobenzene side‐groups.
New Regular, Amphiphilic Poly(ampholyte)s: Synthesis and Characterization
Authors: Rullens François , Devillers Michel , Laschewsky André
Published: May 2004

Summary:Hydrophobically substituted diallylamines bearing a hexyl, dodecyl, or octadecyl chain were synthesized and homopolymerized as hydrochlorides. Copolymerization of the diallylamines with maleic acid produces alternating copolymers. The copolymers behave as amphiphilic polyampholytes and dissolve best in the acidic or in the basic form. Only the copolymer with the hexyl chain could be dissolved in aqueous solvents and shows hydrophobic association. The copolymers with the longer alkyl chains require polar protic organic solvents. All polymers are amorphous, but show a superstructure in bulk due to their amphiphilicity.

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Novel Photosensitive Fluorinated Poly(arylene ether) Having Zero Birefringence
Authors: Li Xiang‐Dan , Zhong Zhen‐Xin , Kim Jang J. , Lee Myong‐Hoon
Published: May 2004

Summary: A novel photosensitive fluorinated poly(arylene ether) containing chalcone units was synthesized from decafluorinated chalcone and fluorinated bisphenol at low temperature. Upon UV irradiation, the refractive indices of the polymer film were decreased because of the reduction of electronic polarizability in the chalocone moiety. The decrease was more significant in the in‐plane direction than in the out‐of‐plane direction, and consequently, zero birefringence (at 632.8 nm) was obtained after 90 s of exposure.

The changes in the refractive indices and the birefringence of chalcone‐containing fluorinated poly(arylene ether) films synthesized and measured at 632.8 nm with respect to UV irradiation time.

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The changes in the refractive indices and the birefringence of chalcone‐containing fluorinated poly(arylene ether) films synthesized and measured at 632.8 nm with respect to UV irradiation time.
Nano‐Structural Observation of in situ Silica in Natural Rubber Matrix by Three Dimensional Transmission Electron Microscopy
Authors: Ikeda Yuko , Katoh Atsushi , Shimanuki Junichi , Kohjiya Shinzo
Published: June 2004

Summary: Three dimensional (3D) nanostructures of particulate silicas in natural rubber (NR) were observed for the first time by use of 3D transmission electron microscopy (3D‐TEM) combined with electron tomography. The method enabled us to visualize and evaluate structural characteristics in 3D space, such as the size and the volume of in situ silica generated in the NR matrix by the sol‐gel reaction of tetraethoxysilane, at nanometer scale resolution.

The reconstructed mass density view of the silica in an in situ silica‐filled natural rubber vulcanizate, as determined by 3D‐TEM.

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The reconstructed mass density view of the silica in an in situ silica‐filled natural rubber vulcanizate, as determined by 3D‐TEM.
In situ Reaction and Radiation Protection Properties of Gd(AA)3/NR Composites
Authors: Liu Li , He Lei , Yang Cheng , Zhang Wan , Jin Ri‐Guang , Zhang Li‐Qun
Published: June 2004

Summary: For the first time, a series of Gd(AA)3/NR (natural rubber) composites for X‐ray shielding were prepared by an in situ reaction method. Occurrence of the in situ polymerization of Gd(AA)3 in composites during vulcanization of NR with peroxide greatly improves the dispersion level of the shielding phase by the remarkable reduction of Gd(AA)3 particle size and the formation of small sized poly‐Gd(AA)3 from the matrix. As expected and assumed, the X‐ray shielding properties of all composites apparently increase with the increase of the degree of dispersion of Gd(AA)3 in composites.

The ability of the composites to shield X‐ray radiation increases with an increase in Gd(AA)3 content and as the degree of in situ polymerization of Gd(AA)3 increases (i.e., as t tends towards t100).

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The ability of the composites to shield X‐ray radiation increases with an increase in Gd(AA)3 content and as the degree of in situ polymerization of Gd(AA)3 increases (i.e., as t tends towards t100).
Photopatterning of Crosslinkable Hole‐Conducting Materials for Application in Organic Light‐Emitting Devices
Authors: Bacher Erwin , Jungermann Steffen , Rojahn Markus , Wiederhirn Valérie , Nuyken Oskar
Published: June 2004

Summary: Modern multilayer organic light‐emitting devices (OLED) are fabricated easily and at low cost by spin‐coating with subsequent crosslinking of the layers. For this purpose, a low‐molecular‐weight hole‐transport material based on triphenyl amines bearing crosslinkable oxetane groups was synthesized. Crosslinking of the spin‐coated layer was initiated with UV irradiation using an iodonium‐salt photoinitiator and was observed using realtime FT‐IR spectroscopy. Standard photolithography techniques can be used for structuring the material on the micrometre scale.

An AFM image of the photopatterned bis‐oxetane‐functionalized low‐molecular‐weight hole‐transport material based on triphenyl amines synthesized here.

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An AFM image of the photopatterned bis‐oxetane‐functionalized low‐molecular‐weight hole‐transport material based on triphenyl amines synthesized here.