bluuebunny/crossref_metadata_2025 huggingface dataset:
Similar chromosomal changes in cisplatin and oxaliplatin‐resistant sublines of the H69 SCLC cell line are not associated with platinum resistance
Authors: Stordal Britta , Peters Greg , Davey Ross
Published: September 2006

Small cell lung cancer (SCLC) initially responds well to DNA damaging drugs such as cisplatin, however this is transitory as resistance normally develops. To investigate whether changes in chromosomal copy number caused by platinum drug treatment contributes to platinum resistance, we have analyzed H69 SCLC cells and two low‐level platinum‐resistant sublines, H69CIS200 and H69OX400, derived by cisplatin and oxaliplatin treatment, respectively. Affymetrix 10K SNP array showed that cisplatin and oxaliplatin have independently caused similar changes including loss of segments 6q21‐qter and 13pter‐13q.14.11 and duplication of chromosome 21. Interestingly, despite using equally cytotoxic doses of drug in the development of the cell lines, oxaliplatin caused three times more chromosomal changes than cisplatin. The resistant cell lines lose their resistant phenotype after 3 months of drug‐free culture. The revertant cell lines, denoted H69CIS200‐S and H69OX400‐S, were also analyzed by Affymetrix array to determine if chromosomal changes associated with resistance remain after the resistant phenotype is lost. In the H69OX400‐S many of the changes observed in the resistant cells were absent suggesting that they contributed to the resistant phenotype including: loss of 1q23.3‐qter, 10q11.23, and 19q13.12‐q13.2 and duplication of segments 6p21.2‐p12.3, 16q12.1‐16q13, 16q21‐q23.1, and 19q12. However, out of the similar changes induced by cisplatin and oxaliplatin, both the loss of 6q21‐qter and gain of 21 were still present in the H69CIS200‐S and H69OX400‐S cells. This suggests that cisplatin and oxaliplatin induced similar changes due to inherent vulnerabilities in the H69 cells rather than changes associated with platinum resistance. © 2006 Wiley‐Liss, Inc.
Riparian influence on hyporheic‐zone formation downstream of a small dam in the Blackland Prairie region of Texas
Authors: Duke Jacquelyn R. , White Joseph D. , Allen Peter M. , Muttiah Ranjan S.
Published: September 2006

Small‐order streams have highly variable flows that can result in large temporal and spatial variation of the hyporheic zone. Dam construction along these intermittent headwater streams alters downstream flow and influences the hydrologic balance between stream water and the adjacent riparian zone. A 3‐year site study was conducted along an impounded second‐order stream to determine the water balance between stream, unsaturated zone, groundwater and riparian vegetation. The presence of the upstream impoundment provided near‐perennial water flow in the stream channel. The observed woody plant transpiration accounted for 71% of average annual water loss in the site. The overall contribution of stream water via the hyporheic zone to site water balance was 73 cm, or 44% of total inputs. This exceeded both rainfall and upland subsurface contribution to the site. A highly dynamic hyporheic zone was indicated by high water use from woody plants that fluctuated seasonally with stream water levels. We found leaf area development in the canopy layer to be closely coupled with stream and groundwater fluctuations, indicating its usefulness as a potential indicator of site water balance for small dam systems. The net result of upstream impoundment increased riparian vegetation productivity by influencing movement of stream water to storage in the groundwater system. Copyright © 2006 John Wiley & Sons, Ltd.
Lumped hysteretic model for subsurface stormflow developed using downward approach
Authors: Ewen John , Birkinshaw Stephen J.
Published: September 2006

The terms ‘downward’ and ‘upward’ (synonymous with ‘top‐down’ and ‘bottom‐up’ respectively) are sometimes used when describing methods for developing hydrological models. A downward approach is used here to develop a lumped catchment‐scale model for subsurface stormflow at the 0·94 km2 Slapton Wood catchment. During the development, as few assumptions as possible are made about the behaviour of subsurface stormflow at the catchment scale, and no assumptions are made about its behaviour at smaller scales. (In an upward approach, in contrast, the modelling would be based on assumptions about, and data for, the behaviour at smaller scales, such as the hillslope, plot, and point scales.) The model has a single store with a relatively simple relationship between discharge and storage, based on equations describing hysteretic patterns seen in a graph of discharge against storage. Double‐peaked hydrographs have been observed at the catchment outlet. Rainfall on the channel and infiltration‐excess and saturation‐excess runoff give a rapid response, and shallow subsurface stormflow gives a delayed response. Hydrographs are successfully simulated for the large delayed responses observed in 1971–1980 and 1989–1991, then a lumped model for the rapid response is coupled to the lumped hysteretic model and some double‐peaked hydrographs simulated. A physical interpretation is developed for the lumped hysteretic model, making use of information on patterns of perched saturation observed in 1982 on a hillslope at the Slapton Wood catchment. Downward and upward approaches are complementary, and the most robust way to develop and improve lumped catchment models is to iterate between downward and upward steps. Possible next steps are described. Copyright © 2006 John Wiley & Sons, Ltd.
D and 18O enrichment measurements in biological fluids in a continuous‐flow elemental analyser with an isotope‐ratio mass spectrometer using two configurations
Authors: Ripoche N. , Ferchaud‐Roucher V. , Krempf M. , Ritz P.
Published: September 2006

In doubly labelled water studies, biological sample enrichments are mainly measured using off‐line techniques (equilibration followed by dual‐inlet introduction) or high‐temperature elemental analysis (HT‐EA), coupled with an isotope‐ratio mass spectrometer (IRMS). Here another continuous‐flow method, (CF‐EA/IRMS), initially dedicated to water, is tested for plasma and urine analyses.

The elemental analyser configuration is adapted for each stable isotope: chromium tube for deuterium reduction and glassy carbon reactor for 18O pyrolysis. Before on‐line conversion of water into gas, each matrix is submitted to a short and easy treatment, which is the same for the analysis of the two isotopes. Plasma is passed through centrifugal filters. Urine is cleaned with black carbon and filtered (0.45 µm diameter).

Tested between 150 and 300 ppm in these fluids, the D/H ratio response is linear with good repeatability (SD < 0.2 ppm) and reproducibility (SD < 0.5 ppm). For 18O/16O ratios (from 2000 to 2200 ppm), the same repeatability is obtained with a between‐day precision lower than 1.4 ppm. The accuracy on biological samples is validated by comparison to classical dual‐inlet methods: 18O analyses give more accurate results. The data show that enriched physiological fluids can be successfully analysed in CF‐EA/IRMS. Copyright © 2006 John Wiley & Sons, Ltd.
The influence of atmospheric circulation at different spatial scales on winter drought variability through a semi‐arid climatic gradient in Northeast Spain
Authors: Vicente‐Serrano Sergio M. , López‐Moreno Juan I.
Published: September 2006

This paper analyses the spatial and temporal variability of winter droughts in a semi‐arid geographic gradient in Northeast Spain, from the Pyrenees in the north to the Mediterranean coastland in the south. Droughts that occurred between 1952 and 1999 were analysed by means of the Standardised Precipitation Index (SPI). The influence of the weather‐type frequency and of the general North Atlantic atmospheric circulation patterns was analysed. The results indicate that winter droughts show an important spatial variability in the study area, differentiating three well‐defined patterns. These correspond to the Pyrenees, the centre of the Ebro Valley, and the Mediterranean coastland. General negative trends in winter SPI have been found, which are indicative of the increase in winter drought conditions in the study area. Nevertheless, important spatial differences have also been recorded. Dominant north–south gradients in the influence of weather types are shown. Moreover, the negative trends in winter‐SPI values agree with the negative trend in the frequency of the weather types prone to cause precipitation, such as the C, SW and W weather types and the increase in the frequency of A weather types. Nevertheless, in the Mediterranean coastland, the positive trend in SPI values agrees with the increase in the frequency of weather types of the east (E, SE), which are prone to cause precipitation in this area. Interannual variations in the frequency of the different weather types have been highly determined by different general atmospheric circulation patterns, mainly the North Atlantic Oscillation (NAO). Nevertheless, the correlation between the time series of weather‐type frequency and the winter SPI is higher than that found between the SPI and the NAO. Thus, although the interannual NAO variability explains a high percentage of the interannual differences in the frequency of different weather types, it is not sufficient to explain the spatial and temporal variability of droughts, which respond better to atmospheric variability at more detailed (synoptic) spatial scales. Copyright © 2006 Royal Meteorological Society.
The Western Mediterranean Oscillation and rainfall in the Iberian Peninsula
Authors: Martin‐Vide Javier , Lopez‐Bustins Joan‐Albert
Published: September 2006

Seasonal precipitation variability in the east of the Iberian Peninsula is weakly linked to the North Atlantic Oscillation (NAO) during autumn and winter. For the purpose of improving the study of its performance, low‐frequency variability patterns specific to the Mediterranean basin have been searched for. In this way, the Western Mediterranean Oscillation (WeMO) has been defined by means of the dipole composed, in its positive phase, by the anticyclone over the Azores and the depression over Liguria, and its index (WeMOi), as a result of the difference of the standardised values in surface atmospheric pressure in San Fernando (Spain) and Padua (Italy). This new index allows the detection of the variability relevant to the cyclogenesis next to the western Mediterranean basin, which determines in a predominant way the types of rainfall in the Gulf of Valencia. In this area, the WeMO is significantly better than the NAO to explain the monthly pluviometric anomalies during these seasons. Also, a daily resolution of the WeMOi can provide a useful tool to forecast torrential rainfall events in the north‐western zones of the Mediterranean (eastern part of the Iberian Peninsula and the south of France), and such significantly daily rainfall frequencies for different thresholds. Copyright © 2006 Royal Meteorological Society.
European cyclone track analysis based on ECMWF ERA‐40 data sets
Authors: Bartholy Judit , Pongrácz Rita , Pattantyús‐ábrahám Margit
Published: September 2006

Changes in large‐scale circulation patterns over the North‐Atlantic‐European region are presented and analyzed for the 20th century. First, changes in decadal frequency of Hess‐Brezowsky macrocirculation patterns (MCP) are evaluated for the period between 1881 and 2000. Frequency of several MCP types increased or decreased considerably during these 120 years, which may be explained by large‐scale changes in circulation characteristics, e.g. by changes in cyclone activity in the different regions. Therefore, cyclone center identification and cyclone tracks and intensity analysis have been accomplished on the basis of the European Centre for Medium‐range Weather Forecast (ECMWF) reanalysis data sets (ERA‐40) on a 2.5° horizontal resolution grid for the period between 1957 and 2002. Results suggest that both the number of midlatitude cyclones and the cyclone activity increased considerably in the North‐Atlantic‐European region, especially in the northwestern part of the domain. Copyright © 2006 Royal Meteorological Society.
Spatial differentiation of air temperature in Poland using circulation types and GIS
Authors: Ustrnul Zbigniew
Published: September 2006

This paper is devoted to the synoptic–climatic analysis with the application of circulation types and Geographic Information Systems (GIS). Construction of daily climatic air temperature maps for the Polish territory was the main aim of the work. Analysis was based on the mean daily temperature data from all synoptic and some climatological stations (73 stations totally) for the 50‐year period of 1951–2000. The synoptic–climatic analysis was done using a well known circulation calendar developed by the German Meteorological Service ‘Grosswetterlagen’. Residual kriging was chosen for the map constructions. Several geographic parameters, including elevation, latitude, longitude, and distance to the Baltic coast, were used as predictor variables for air temperature. However, the particular circulation type was the crucial predictor. Maps were created for all months for the Grosswetterlagen circulation types, which occurred more than 30 times during 1951–2000. Special attention was paid to the extreme thermal months of January and July. Maps constructed in the way described confirmed that application of circulation types was quite a good tool for improving accuracy of thermal daily maps. Accuracy was much higher for most of the maps constructed for particular circulation types than for the maps created without application of circulation types. There was only one exception: non‐advective anticyclonic types during winter time. Then, relatively large variability of the temperature can be observed in the concave landforms and the constructed maps have only approximate meaning. Copyright © 2006 Royal Meteorological Society.
Variability in the characteristics of cut‐off low pressure systems over subtropical southern Africa
Authors: Singleton A. T. , Reason C. J. C.
Published: September 2006

Variability in the characteristics of cut‐off low pressure systems over subtropical southern Africa is examined for the 1973–2002 period. These characteristics include their seasonality, frequency, duration, location and size. It is found that on average 11 cut‐off lows occur over southern Africa south of 20°S per year and are most common in the March‐May season. Potential relationships between the number of cut‐off lows over southern Africa with the El Niño Southern Oscillation (ENSO), the Pacific South America pattern, the wave number 3 pattern and the semi‐annual oscillation (SAO) are discussed. La Niña years appear to be associated with above average annual frequencies of cut‐off lows but the reverse is generally not true for El Niño years. There was a shift in the preferred season for cut‐off lows from March–May to June–August in the 1980s, which coincided with a weakening of the SAO and a shift in zonal wave number 3. This period also showed a change in the preferred location of these systems from southwestern subtropical southern Africa to the northeast of the region. The results suggest that there may be a relationship between cut‐off lows over subtropical southern Africa, the wave number 3 pattern in the Southern Hemisphere and the SAO. Copyright © 2006 Royal Meteorological Society.
Determination of some biochemical properties of polyphenol oxidase from Emir grape (Vitis vinifera L. cv. Emir)
Authors: Ünal M Ümit , Şener Aysun
Published: September 2006

Polyphenol oxidase (PPO) was extracted from Emir grapes grown in Turkey and its characteristics in terms of pH and temperature optima, thermal inactivation, kinetic parameters and potency of some PPO inhibitors were studied. The optimum pH and temperature for grape PPO were found to be 4.2 and 25 °C respectively using catechol as substrate. Km and Vmax values were found to be 25.1 ± 2.72 mmol L−1 and 0.925 ± 0.04 OD410 min−1 respectively. Of the inhibitors tested, the most potent was sodium metabisulfite, followed by ascorbic acid. The thermal inactivation curve was biphasic. Activation energy (Ea) and Z values were calculated as 251.4 kJ mol−1 (r2 = 0.996) and 8.92 °C (r2 = 0.993) respectively. Copyright © 2006 Society of Chemical Industry
Accumulation of β‐catenin protein, mutations in exon‐3 of the β‐catenin gene and a loss of heterozygosity of 5q22 in solid pseudopapillary tumor of the pancreas
Authors: Min Kim Seong , Sun Chuan Dong , Park Ki Chung , Kim Ho Guen , Lee Woo Jung , Choi Seung Hoon
Published: September 2006

Background

Solid pseudopapillary tumors (SPT) of the pancreas are neoplasms with a low malignant potential. The molecular events contributing to the pathogenesis of SPTs are still unknown.

Objectives

This study was intended to help better understand the early steps of human SPT development.

Methods

We microdissected 20 SPTs and normal pancreatic tissue. In addition, we examined the DNA from each SPT for mutations in exon‐3 of β‐catenin and loss of heterozygosity (LOH) on 9 chromosome arms using 10 microsatellite markers. Immunohistochemical staining for β‐catenin was performed.

Results

Activating mutations between codons 32 and 37 of β‐catenin exon‐3 were present in 16 cases (80%). Allelic loss on chromosome 5q22.1 was present in 10 cases (55.5%), while no allelic loss was found on chromosomes 1p, 6q, 9p, 9q, 11p, 11q, 17p, or 22q. Nuclear accumulation of β‐catenin was found in 20 cases (100%).

Conclusion

Mutations in exon‐3 of the β‐catenin gene, nuclear accumulation of β‐catenin, and LOH on chromosome 5q22.1 in SPT tissue suggest that these mutations are involved in SPT tumorigenesis. J. Surg. Oncol. 2006;94:418–425. © 2006 Wiley‐Liss, Inc.
High expressions of CD105 and VEGF in early oral cancer predict potential cervical metastasis
Authors: Chien Chih‐Yen , Su Chih‐Ying , Hwang Chung‐Feng , Chuang Hui‐Ching , Chen Ching‐Mei , Huang Chao‐Cheng
Published: September 2006

Background and Objectives

Although elective neck dissection has become a popular treatment modality for early oral cancer among most head and neck surgeons, a large portion of patients revealed pathological N0 postoperatively. Our study is aimed to evaluate the expressions of the angiogenic factors, vascular endothelial growth factor (VEGF), and CD105 (endoglin) on the prediction of neck metastasis for clinical N0 patients in early oral cancer.

Patients and Methods

Between July 1996 and July 2005, the preoperative biopsy specimens among 176 patients who underwent surgical treatment for early oral cancer were retrieved for the immunohistochemical study for VEGF and CD105.

Results

High expressions of CD105 and VEGF significantly correlated with positive nodal metastasis, respectively (P < 0.001). The expression of CD105 also significantly correlated with that of VEGF (P < 0.001). Furthermore, the sensitivity and specificity for prediction of cervical metastasis by high expressions of CD105 versus VEGF were 81.8% and 97.7% versus 93.2% and 72%, respectively. Low expression of CD105 and VEGF also significantly correlated with higher survival rate, respectively (P < 0.001).

Conclusions

Besides the image studies, the expressions of both CD105 and VEGF could be useful to guide the elective treatment for clinical N0 neck in early oral cancer. J. Surg. Oncol. 2006;94:413–417. © 2006 Wiley‐Liss, Inc.
High operative risk of cool‐tip radiofrequency ablation for unresectable pancreatic head cancer
Authors: Wu Yulian , Tang Zhe , Fang Heqing , Gao Shunliang , Chen Jian , Wang Yong , Yan Haichao
Published: September 2006

Background and Objectives

To report and discuss the effect, complications and mortality of cool‐tip radiofrequency ablation (RFA) for unresectable pancreatic cancer.

Methods

During October 2003 to July 2004, sixteen patients with unresectable pancreatic cancer were treated by open cool‐tip RFA. One‐half of the 16 patients had tumors located in the pancreatic head. A 5‐mm minimum safe distance between RFA site and major peripancreatic vessels was kept to avoid injury to the vessels.

Results

Six of twelve patients with back pain got pain relief postoperatively. Pancreatic fistula occurred in three patients (18.8%) and healed smoothly in 7–10 days with routine abdominal drainage. The mortality was 25% (4/16). In the four death cases, tumors were all located in the pancreatic head; three patients with tumor close to portal vein died suddenly of massive gastrointestinal hemorrhage on the 4th, 30th, 40th postoperative day respectively and a 79‐year‐old patient died of acute renal failure on the 2nd postoperative day.

Conclusions

Standard use of cool‐tip RFA was dangerous for pancreatic head cancer close to portal vein, in which a 5‐mm minimum safe distance between RFA site and major peripancreatic vessels might not be enough to avoid injury to the vessels. J. Surg. Oncol. 2006;94:392–395. © 2006 Wiley‐Liss, Inc.
Tumour‐positive sentinel node findings in patients with ductal carcinoma in situ
Authors: Leidenius M. , Salmenkivi K. , von Smitten K. , Heikkilä P.
Published: September 2006

Background

Our aim was to evaluate the prevalence of and risk factors for tumour‐positive sentinel node (SN) findings in patients with ductal carcinoma in situ (DCIS).

Methods

Altogether 1,470 patients underwent sentinel node biopsy (SNB) between April 2001 and March 2005 in our unit. According to a histopathological review, 11 of them had microinvasive and 74 pure DCIS and were included in the study.

Results

Five patients (7%) with pure DCIS had SN metastases. Three of them had isolated tumour cells (ITC) only. Axillary clearance without further metastatic findings was performed in three patients. The median histological size of DCIS was larger, 50 (45–60) mm in patients with metastatic SN findings than the median of 18 (2–110) mm in those with tumour‐negative SN, P = 0.0103. All five patients with metastatic SN findings underwent mastectomy. Metastatic SN findings were detected in one (9%) patient with microinvasive DCIS.

Conclusions

Metastatic SN findings in patients with pure DCIS may be a sign of missed invasion. J. Surg. Oncol. 2006;94:380–384. © 2006 Wiley‐Liss, Inc.
Ipsilateral breast tumor reappearance in patients treated with conservative surgery after primary chemotherapy. The role of surgical margins on outcome
Authors: Gentilini Oreste , Intra Mattia , Gandini Sara , Peruzzotti Giulia , Winnikow Erik , Luini Alberto , Veronesi Paolo , Galimberti Viviana , Goldhirsch Aron , Veronesi Umberto
Published: September 2006

Background and Objectives

To evaluate the ipsilateral breast tumor reappearance (IBTR) rate after breast conservative surgery (BCS) following primary chemotherapy (PC) and to assess whether positive margins affects IBTR rate and overall survival (OS).

Methods

Three hundred nine women candidates for mastectomy received PC before surgery. One hundred ninety‐five patients (63.1%) underwent BCS and 114 patients (36.9%) a modified radical mastectomy.

Results

After a median follow‐up of 41 months (range 7–90), 13 patients of the 195 treated with BCS had an IBTR (6.7%), 6 patients had a regional relapse (3.1%), 28 women had distant metastases (14.4%). Twenty‐three patients died of breast cancer (11.8%). Twenty‐four patients treated with BCS had positive margins (12.3%). At 3 years, the crude cumulative incidence of local recurrence was 4.7% in women with negative margins, and 13.3% in women with positive margins (P = 0.05). Cumulative incidence of distant metastases was similar in patients with positive and negative margins (P = 0.16) and there was no significant difference in terms of OS according to the margin status (P = 0.577).

Conclusions

BCS after PC has an acceptable rate of IBTR. After a short follow‐up, the presence of positive margins does not affect OS. J. Surg. Oncol. 2006;94:375–379. © 2006 Wiley‐Liss, Inc.
Added value of ultrasound in screening the clinically negative axilla in breast cancer
Authors: Mathijssen I.M.J. , Strijdhorst H. , Kiestra S.K. , Wereldsma J.C.J.
Published: September 2006

Background

For staging purposes in breast cancer it is current practice to perform a sentinel node biopsy in a clinically negative axilla, followed by an axillary lymph node dissection if metastases are found in the sentinel node. To limit the number of surgical procedures it is therefore of importance to try and identify as much patients as possible who have axillary metastases. Clinical staging of the axillary nodes in breast cancer is mainly based on palpation, but ultrasound has been shown to be of additional value in detecting pathological nodes.

Methods

In this paper, we report our results of screening 131 breast cancer patients without palpable axillary nodes through ultrasound.

Results

Out of the 53 patients with axillary node involvement, 18 were identified as such by our radiologist, resulting in a detection score of 34%.

Discussion

This high rate is probably reached because of the limited number of radiologists performing this procedure, thereby rapidly increasing their experience. J. Surg. Oncol. 2006;94:364–367. © 2006 Wiley‐Liss, Inc.
Primary angiosarcoma of the breast: Observations in Asian Indian women
Authors: Shet Tanuja , Malaviya Alopa , Nadkarni Mandar , Kakade Anagha , Parmar Vani , Badwe Rajan , Chinoy Roshni
Published: September 2006

Background

Primary angiosarcomas of breast are rare tumors, with a fatal outcome.

Material and Methods

We studied histological prognostic factors and c‐kit expression by immunohistochemistry (IHC) in 12 angiosarcomas accessioned at a cancer referral center in India.

Results

All patients had primary angiosarcoma; no case of secondary angiosarcoma was accessioned during the study period. Median age of patients was 24.5 years. Nine patients had intermediate grade tumors, one a well differentiated tumor and three patients had high‐grade tumors. Interesting cases encountered included an epithelioid angiosarcoma and an angiosarcoma arising on the background of a biphasic tumor. Eight patients had lumpectomy, four mastectomy and two patients were given radiotherapy. Of the nine patients (seven type I/II and two high grade) with follow up, eight patients developed disseminated metastases within a year of presentation. The patient with well‐differentiated angiosarcoma also died of metastasis albeit after a longer time. On IHC c‐kit staining was weakly seen in two cases.

Conclusion

Primary angiosarcoma was fatal in young Indian women even in lower grade tumors. The low expression of c‐kit on IHC suggests that targeting this protein for therapy may not be successful in treating these tumors. J. Surg. Oncol. 2006;94:368–374. © 2006 Wiley‐Liss, Inc.
Symmetrization reduction mammaplasty combined with sentinel node biopsy in patients operated for contralateral breast cancer (J. Surg. Oncol. 2006;94:9–15)
Authors: Schrenk Peter , Wölfl Soraya , Bogner Sephan , Huemer Georg , Wayand Wolfgang
Published: September 2006

The original article to which this Erratum refers was published in J. Surg. Oncol. 2006;94:9–15.
Structure of Algal‐Born Phenolic Polymeric Adhesives
Authors: Bitton Ronit , Ben‐Yehuda Maya , Davidovich Maya , Balazs Yael , Potin Philippe , Delage Ludovic , Colin Carole , Bianco‐Peled Havazelet
Published: September 2006

Summary: Adhesive materials extracted from the brown alga Fucus serratus are composed of phenolic polymer, alginate, and CaCl2. The phenolic polymer undergoes an oxidation reaction in the presence of bromoperoxidase, KI, and H2O2. The nanostructure of the adhesive was investigated using small angle X‐ray scattering, light scattering, and cryo‐ transmission electron microscopy experiments. These have shown that the phenolic polymer undergoes self‐assembly and forms flexible chain‐like objects. Oxidation or adding alginate does not alter this structure. However, once calcium ions are added, a rigid network is formed. Presumably, this network is responsible for the cohesive strength of the glue.

A schematic illustration of the spatial arrangement of the glue: oxidized polyphenol encapsulated by the alginate gel network.

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A schematic illustration of the spatial arrangement of the glue: oxidized polyphenol encapsulated by the alginate gel network.
Loading and Release of Ibuprofen in Multi‐ and Monofilament Surgical Sutures
Authors: Zurita Raül , Puiggalí Jordi , Rodríguez‐Galán Alfonso
Published: September 2006

Summary: The preparation of mono‐ and multifilament sutures incorporating ibuprofen as an anti‐inflammatory agent is considered. Poly(p‐dioxanone) monofilament samples can be loaded by a molecular diffusion process using a swelling agent such as dichloromethane. The mechanical properties have been measured and have not shown a significant change for the ibuprofen loaded samples in knot tensile assays. The kinetics of both the loading process and the release in a Sörensen's medium at 37 °C have been investigated. Diffusion coefficients have also been estimated from film and slab poly(p‐dioxanone) samples containing ibuprofen and their release behavior compared to that shown by monofilaments. Release from a coating copolymer based on lactide, ε‐caprolactone and trimethylene carbonate (PLA/PCA/PTMC 10/60/30) has also been studied. This coating solubilizes ibuprofen molecules well and can be used for braided sutures or when a rapid dose of ibuprofen is preferred.

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Surface Behavior and Molecular Recognition in DNA Microarrays from N,N‐Dimethylacrylamide Terpolymers with Activated Esters as Linking Groups
Authors: Suriano Raffaella , Levi Marinella , Pirri Giovanna , Damin Francesco , Chiari Marcella , Turri Stefano
Published: September 2006

Summary: A series of terpolymers made of DMA, NAS and MAPS were synthesized by free radical copolymerization and used as functional coatings for the fabrication of glass slide DNA microarrays. The surface properties of coated glass slides were investigated through contact angle measurements, ellipsometry and atomic force microscopy. The terpolymer molecular weight showed a moderate effect on surface tension (γs = 56–62 mN · m−1), but no clear effect on polymeric layer thickness (5–8 nm) and roughness. Hybridization experiments with amine‐functionalized oligonucleotides gave the best fluorescence intensity results for microarrays coated with intermediate‐molecular‐weight terpolymers. Finally, an accelerated ageing test of the microarray in a humidity chamber showed a nice relationship between decay curves of contact angle against water and fluorescence intensity.

Details of fluorescence microscope images after hybridization of the probe H2N‐oligonucleotide spotted on the polymeric coatings.

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Details of fluorescence microscope images after hybridization of the probe H2N‐oligonucleotide spotted on the polymeric coatings.
Melt Spinning of Poly(3‐hydroxybutyrate) Fibers for Tissue Engineering Using α‐Cyclodextrin/Polymer Inclusion Complexes as the Nucleation Agent
Authors: Vogel Roland , Tändler Bernhard , Häussler Liane , Jehnichen Dieter , Brünig Harald
Published: September 2006

Summary: This paper reports on an attempt to use CD and CD/PHB ICs as nucleation agents for PHB in a high‐speed melt spinning process. At first rheological and thermal properties of the nucleated melts are determined in order to assess the influence of the nucleating agents. Then spinning tests are carried out. Thermal and textile properties of the spun PHB fibers are also determined. An estimation of the improvement of inhibition of the secondary crystallization from use of the described blood compatible nucleating agents is given.

An example of a nucleation agent.

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An example of a nucleation agent.
Silicone‐Organic Resin Hybrid Matrix Composites
Authors: Zhu Bizhong , Wu Yuhong , Reese Herschel H. , Katsoulis Dimitris E. , McGarry Frederick J.
Published: September 2006

Summary: Glass fabric reinforced hybrid matrix composites of a toughened silicone resin and a vinyl ester resin were fabricated and their properties investigated. The hybrid composites consisted of multi‐layers of fiber reinforced silicone resins and vinyl ester resins. The toughened silicone resin, a crosslinkable phenylsilsesquioxane resin with high thermal and thermal oxidation resistance but relatively low Tg, was chosen to be the outer layers. The vinyl ester resin, with better strength, toughness and a much higher Tg than the toughened silicone resin, was used as the inner layers. A co‐cure process proved to establish a strong interface between the two in a hybrid composite. The hybrid composites had better flammability properties and much lower short term moisture absorption than the vinyl ester composites. The strength and modulus retention of the hybrid composites at elevated temperatures was higher than the composites using any single resin as the matrix. For example, when tested at 150 °C the flexural modulus and strength values of a twelve layer composite, with eight inner vinyl ester resin layers and four silicone outer layers, were almost an order of magnitude higher than the composite using the silicone resin alone, and were significantly higher than the one using vinyl ester resin alone. The room temperature short beam shear strength of the hybrid composites was also higher. DMA revealed that the inter‐diffusion of reactive components between the two resins was probably responsible for this synergistic effect, resulting in an α transition temperature of 182 °C for the hybrid composite, higher than that of either the silicone resin (85 °C) or the vinyl ester resin (162 °C).

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Preparation and Swelling Properties of Temperature‐Sensitive Semi‐Interpenetrating Polymer Networks Composed of Poly[(N‐tert‐butylacrylamide)‐co‐acrylamide] and Hydroxypropyl Cellulose
Authors: Çaykara Tuncer , Şengül Gamze , Birlik Gökçen
Published: September 2006

Summary: Temperature‐responsive hydrogels based on linear HPC and crosslinked P(NTBA‐co‐AAm) were prepared by the semi‐IPN technique. The structure of these semi‐IPN hydrogels was investigated by FT‐IR spectroscopy. An increase in normalized band ratios (A2980/A1665) was observed with increasing HPC content in the initial mixture. The swelling kinetics and water transport mechanism of these semi‐IPN hydrogels were examined and their temperature responsive behaviors were also investigated by measuring equilibrium swelling ratios and pulsatile swelling experiments. The results showed that these semi‐IPN hydrogels underwent a volume phase transition between 18 and 22 °C irrespective of the amounts of MBAAm and HPC. However, below the volume phase transition temperature, their equilibrium swelling ratios were affected by the amount of MBAAm and HPC. The pulsatile swelling experiments indicated that the lower the MBAAm and the higher HPC contents in semi‐IPN hydrogels the faster the response rate temperature change.

Equilibrium swelling ratios of the semi‐IPN P(NTBA‐co‐AAm)/HPC hydrogels in water shown as a function of temperature.

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Equilibrium swelling ratios of the semi‐IPN P(NTBA‐co‐AAm)/HPC hydrogels in water shown as a function of temperature.
Studies on Hydrotalcite‐Catalyzed Synthesis of Poly(ethylene terephthalate)
Authors: El‐Toufaili Faissal‐Ali , Ahmadniana Fatemeh , Dinse Arne , Feix Gunter , Reichert Karl‐Heinz
Published: September 2006

Summary: The hydrotalcite‐catalyzed synthesis of PET was studied to clarify the effect of hydrotalcite properties on its catalytic activity. Hydrotalcite was modified by various treatments to tune its activity as a polycondensation catalyst. Hydrotalcite activity was found to decrease upon calcination. However, rehydration of the calcinated hydrotalcite resumed the catalytic activity. The hydrotalcite activity depends on the ratio of magnesium to aluminum cations in its composition, and highest activity occurs at a molar ratio of 2:1. Replacement of the carbonate anions of hydrotalcite by more nucleophilic ones like hydroxide and alkoxide groups resulted in improved catalytic activity. Hydrotalcite has two assembly orders: primary lamination of sheets into plates and secondary agglomeration of plates into particles. Hydrotalcite with larger sheet size showed lower activity. On the other hand, milling of hydrotalcite particles did not affect its activity as it probably enters the reaction on a plate level, which is not affected by milling. Polycondensation resulted in expansion of the hydrotalcite sheets under the effect of formed polymer. Reuse of hydrotalcite after polycondensation followed by depolycondensation resulted in a large activity enhancement.

High‐resolution SEM micrograph of calcinated HT after rehydration.

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High‐resolution SEM micrograph of calcinated HT after rehydration.
Morphology and Crystalline Structure of Poly(ε‐Caprolactone) Nanofiber via Porous Aluminium Oxide Template
Authors: Chen Yang , Zhang Lina , Lu Xiaoying , Zhao Ning , Xu Jian
Published: September 2006

Summary: Poly(ε‐caprolactone) (PCL) nanofibers with a dimension of about 150 nm were successfully fabricated by using a process of extruding PCL solution via a porous aluminium oxide template and then solidifying in methanol. The morphology, melting behavior and crystalline structure of the nanofibers were investigated by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and X‐ray diffraction (XRD). The results revealed that the weight‐average molecular weight ($\overline M _{\rm w}$) of PCL hardly influenced the morphology of the nanofibers. However, the melting temperature (Tm) of the PCL crystalline increased slightly from 55.4 to 57.5 °C with an increase in $\overline M _{\rm w}$. The accessional pressure and the presence of the porous template played an important role in the improvement of the orientation and crystallization structures of the polymer chains when they were passing through the nano‐scale porous channel, leading to the conglomeration of the fiber and the much larger diameter than those from the pressure‐induced extrusion process. Furthermore, comparing the processes with and without accessional pressure, the crystallinity of the nanofibers obtained under 0.2 MPa pressure increased, and the diffraction for the (001) lattice plane occurred.

SEM image of PCL nanofibers extruded via a porous aluminium oxide template with the aid of pressure.

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SEM image of PCL nanofibers extruded via a porous aluminium oxide template with the aid of pressure.
High Compatibility and Improved Barrier Performance in Blends Based on a Copolyester Modified with a Poly(amino ether) Resin
Authors: Granado Ainhoa , Eguiazabal José Ignacio , Nazabal Jon
Published: September 2006

Summary: The structure and properties of blends of a PCTG and a PAE resin obtained by direct injection molding have been studied. The blends were almost immiscible, and were composed of a nearly pure PAE phase and a mixed PCTG‐rich phase containing minor PAE amounts. Electron microscopy observations showed a high intermixing level between both components. The permeability data indicated an improved barrier protection of PCTG upon PAE addition. The Young's modulus and the yield stress of the blends followed a linear behavior with respect to composition, while values close or slightly below linearity were observed for the break properties. The combined effects of the small dispersed particle size and the proposed good interfacial adhesion are stated as the main factors responsible for the positive mechanical behavior. The impact strength showed an unexpected variability for PCTG‐rich blends, which is attributed to a ductile‐brittle transition of PCTG.

Ductility of PCTG/PAE blends vs. composition.

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Ductility of PCTG/PAE blends vs. composition.
Functionalization of Poly(propylene) Fabric with 4‐Vinylpyridine, N,N‐Dimethylacrylamide and Styrene by γ‐Radiation‐Induced Grafting in an Aqueous Environment
Authors: Khan Ferdous , Kronfli Esam , Bradley Mark
Published: September 2006

Summary: VP and co‐monomers DMAAm and ST were successfully grafted onto a PP fabric in an emulsion copolymerization process initiated by γ‐radiation. The radiation dose, concentration of VP, the ratio of VP/DMAAm and VP/ST in the reaction solution, and the reaction temperature dependent graft copolymerization were investigated. The order of dependence of the initial rate of grafting on the radiation dose was found to be in the range of 1.2 to 0.93 for VP; 0.84 to 0.70 for VP/DMAAm and for VP/ST was in the range of 0.59 to 0.41. The activation energy of the graft copolymer reaction was determined to be 40.18 J · mol−1 for 0.464 mol · L−1 VP. In the case of co‐monomer mixtures (VP/DMAAm: 0.464/0.5) the energy of activation was noticeably higher at 49.71 J · mol−1 while for VP/ST (0.464/0.436) the activation energy was same as that of VP. XRD results showed that overall crystallinity significantly decreased with the increase of graft weight with a noticeable change in the chemical structure of the PP, indicating that the graft copolymer reaction was taking place both in the amorphous and crystalline regions of PP. A similar characteristic behavior was also obtained by DSC, which revealed the presence of an endotherm process in the range of 25 to 130 °C depending on the degree of grafting, attributed to the grafted chains of the monomer/co‐monomers. In order to determine the graft copolymer reaction of VP, DMAAm and ST onto the backbone of PP, the reaction products were characterized by FTIR spectroscopy. A good correlation was found between changes of crystallinity and level of graft copolymerization as determined by WAXRD and DSC.

Typical XRD traces of as‐received PP fabric (PPF) and grafted with VP (PPF‐g‐VP).

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Typical XRD traces of as‐received PP fabric (PPF) and grafted with VP (PPF‐g‐VP).
Thermal and Mechanical Behavior of Carbon‐Nanotube‐Filled Latex
Authors: Grunlan Jaime C. , Kim Yeon‐Seok , Ziaee Saeed , Wei Xin , Abdel‐Magid Beckry , Tao Kun
Published: September 2006

Summary: Composite films were prepared from a mixture of poly(vinyl acetate) latex and SWNTs. SEM images reveal a segregated SWNT network that grows heavier with increasing concentration. Nanotube segregation is the result of excluded volume created by the much larger polymer particles in the latex. Thermal conductivity exhibits a sharp rise with increasing quantity of nanotubes, although the maximum value is only 10% greater than that of the polymer matrix due to large thermal interface resistance. Storage modulus exhibits a peak and subsequent drop due to pore formation. In the absence of porosity, the Halpin‐Tsai model accurately predicts the composite modulus at 25 °C. The segregated network improves the composite modulus above Tg by nearly an order of magnitude with only 2 wt.‐% SWNT.

Schematic illustration of a segregated network of carbon nanotubes.

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Schematic illustration of a segregated network of carbon nanotubes.
Existence and stability of steady solutions to nonlinear parabolic‐elliptic systems modelling chemotaxis
Authors: Chen Hua , Zhong Xin‐Hua
Published: September 2006

In this paper, we study the existence of non‐constant steady solutions and the linear stability of constant solutions to nonlinear parabolic‐elliptic system, which actually is a simplified form of the Keller–Segel system modelling chemotaxis. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
B ‐sub‐manifolds and their stability
Authors: Li Ma
Published: September 2006

In this paper, we show that the “grim reaper” in the curve‐shortening problem is stable in the sense of “symmetric stable” defined by K. Smoczyk. We also briefly discuss the graphic B ‐minimal sub‐manifold in ℝn +k . (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Connections between the geometry of a projective variety and of an ample section
Authors: Andreatta Marco , Novelli Carla , Occhetta Gianluca
Published: September 2006

LetXbe a smooth complex projective variety and letZ=(s=0) be a smooth submanifold which is the zero locus of a section of an ample vector bundleEof rankrwith dimZ=dimX–r.

We show with some examples that in general the Kleiman–Mori cones NE(Z) and NE(X) are different. We then give a necessary and sufficient condition for an extremal ray in NE(X) to be also extremal in NE(Z).

We apply this result to the caser=1 andZa Fano manifold of high index;in particular we classify allXwith an ample divisor which is a Mukai manifold of dimension ≥4.

In the last section we prove a general result in caseZis a minimal variety with 0 ≤κ(Z) <dimZ. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Linear passive stationary scattering systems with Pontryagin state spaces
Authors: Arov D. Z. , Rovnyak J. , Saprikin S. M.
Published: September 2006

Passive scattering systems having Pontryagin state spaces and their minimal conservative dilations are investigated. The transfer functions of passive scattering systems are generalized Schur functions. In the case of a simple conservative system, the right and left Kreĭn–Langer factorizations of the transfer function correspond to natural cascade syntheses of systems. A generalization of Sz.–Nagy and Foias criteria for a cascade synthesis of two simple conservative systems to be simple is obtained for systems with Pontryagin state spaces. It is shown that the state space of a simple passive system admits certain unique fundamental decompositions, which give rise to a notion of stability and a characterization of simple conservative systems whose transfer functions have unitary boundary values a.e. on the unit circle. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Convergence to steady states of solutions of the Cahn–Hilliard and Caginalp equations with dynamic boundary conditions
Authors: Chill Ralph , Fašangová Eva , Prüss Jan
Published: September 2006

We consider a solution of the Cahn–Hilliard equation or an associated Caginalp problem with dynamic boundary condition in the case of a general potential and prove that under some conditions on the potential it converges, as t → ∞, to a stationary solution. The main tool will be the Łojasiewicz–Simon inequality for the underlying energy functional. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sobolev embeddings for Riesz potential space of variable exponent
Authors: Futamura Toshihide , Mizuta Yoshihiro , Shimomura Tetsu
Published: September 2006

Our aim in this paper is to deal with Sobolev embeddings for Riesz potential spaces of variable exponent. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Geometry and dynamics of some meromorphic functions
Authors: Kotus Janina , Urbański Mariusz
Published: September 2006

Themeromorphic maps fλ (z) = λ (1 – exp(–2z))–1, λ > 0, of the complex plane are thoroughly investigated. With each map fλ associated is its projection Fλ on the infinite cylinder Q. This map and the set Jr (Fλ) consisting of those points in the cylinder Q whose ω ‐limit set under Fλ is not contained in the set {0, –∞} will form the primary objects of our interest in this article. Let hλ = HD(Jr (Fλ)) be the Hausdorff dimension of Jr (Fλ). We prove that hλ ∈ (1, 2). The hλ ‐dimensional Hausdorff measure Hhλ of Jr (Fλ) is proven to be positive and finite. The hλ ‐dimensional packing measure of Jr (Fλ) is shown to be locally infinite at every point of this set. There exists a unique Borel probability Fλ ‐invariant measure μλ on Jr (Fλ) absolutely continuous with respect to the Hausdorff measure Hhλ. This measure turns out to be ergodic and equivalent to Hhλ. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Radius problems for holomorphic mappings on the unit ball in Cn
Authors: Graham Ian , Hamada Hidetaka , Kohr Gabriela
Published: September 2006

In this paper we obtain certain results related to radius of starlikeness, convexity, parametric representation and Bloch radius for some classes of holomorphic mappings on the unit ball B n in ℂn . In particular, we consider the class ℳ︁ of mappings of “positive real part” and some related classes. We also consider two classes of mappings defined by coefficient inequalities. In the last section we consider the complex Hilbert space case of certain results which are treated in the previous sections. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)