bluuebunny/crossref_metadata_2025 huggingface dataset:
Extended Appleby's operation for pancreatic cancer involving celiac axis
Authors: Wu Yu Lian , Yan Hai Chao , Chen Li Rong , Gao Shun Liang , Chen Jian , Dong Xin
Published: September 2007

Background

In Appleby's operation, the adequate flow of proper hepatic artery (PHA) from pancreaticoduodenal arcades was considered to be important in the previous reported pancreatic cancer cases. Insufficient blood flow of PHA was considered as the contraindication for Appleby's operation.

Methods

We herein reported a 20 cm in diameter pancreatic sarcomatoid carcinoma involving celiac axis (CA), which was treated by extended Appleby's operation without proper hepatic arterial flow. The extended Appleby's operation for pancreatic cancer involving CA and/or common hepatic artery (CHA) was firstly applied to the current case according to the 43 previous reported cases in English literature from a Medline search. In the extended Appleby's operation, the resection scope included total pancreas, total stomach, spleen, and CA; the anterior and posterior pancreaticoduodenal arcades were removed in whipple's procedure, which was previously thought to be the contraindication for Applyby's operation.

Results

Proper hepatic arterial flow from superior mesenteric artery (SMA) was totally lost; No liver failure happened postoperatively.

Conclusions

The extended Appleby's procedure without blood flow of PHA might be feasible and offered a new approach to resection of pancreatic cancer involving CA and/or CHA; the involvement of pancreatic head might not be the contraindication for Appleby's operation. J. Surg. Oncol. 2007;96:442–446. © 2007 Wiley‐Liss, Inc.
Hold‐up volume and its application in estimating effective phase ratio and thermodynamic parameters on a polysaccharide‐coated chiral stationary phase
Authors: Lao Wenjian , Gan Jay
Published: September 2007

As an “unretained” marker, 1,3,5‐tri‐tert‐butylbenzene (TTBB) has been commonly used to measure the hold‐up volume. Despite many racemates have been resolved on Chiralcel OJ column, the hold‐up volume of the column is still not well characterized. The aim of this work was to evaluate the chromatographic behavior of TTBB on the OJ column, and its application in estimating the effective phase ratio and thermodynamic parameters. The hold‐up volume was affected not only by the mobile phase composition but also the solvents used for dissolving TTBB. A higher concentration of TTBB (0.500 mg/mL) showed a better reproducibility than when used at a lower concentration. After correction for thermal expansion of the mobile phase, TTBB was found to have slight retention on the OJ phase. The effective phase ratio increased with an increase in the temperature and decrease in the strength of the mobile phase. The enthalpy and entropy of enantiomers of imidazolinone herbicides were independent of the temperature in a linear van't Hoff plot when the effective phase ratio was changed. This study shows that, based on the hold‐up volume from TTBB, thermodynamic evaluation with parameters derived from the distribution constant is valuable for understanding chromatographic retention and enantioseparation mechanisms of chiral analytes.
Targeted determination of the early stage SCLC specific biomarker pro‐gastrin‐releasing peptide (ProGRP) at clinical concentration levels in human serum using LC‐MS
Authors: Winther Bjørn , Moi Petter , Paus Elisabeth , Reubsaet J. Léon E.
Published: September 2007

Pro‐gastrin‐releasing peptide (ProGRP) is used as a specific diagnostic marker for small cell lung cancer (SCLC), a rapidly growing neoplasm with high mortality. Our object was to develop an LC‐MS method for the detection and quantification of ProGRP in human serum using the specific tryptic digestion product NLLGLIEAK (m/z 485.8 for [M + 2H]2+). For this purpose the sample pretreatment, clean‐up, enrichment, and LC‐MS conditions were evaluated. Sample pretreatment was carried out using ACN precipitation to decrease the sample complexity. Although ProGRP (31–98) standards were soluble in 99% ACN, it showed that optimal signal intensities were obtained by adding ACN to the serum in a 1:1 ratio v/v. A simplified tryptic digest protocol was carried out using 100 mM triethanolamine buffer to ensure pH stability during the whole procedure. The simplified protocol also includes omission of reducing and alkylating reagents. Necessary additional sample clean‐up was achieved by trapping NLLGLIEAK on a RAM column (ADS‐C8) which was back‐flushed onto the analytical BioBasic C8 column. Volume of injection, sample enrichment, and column capacity are among the factors optimized to reach a mass LOD of 150 pg on column (OC) ProGRP (31–98). Detection of ProGRP in the serum sample of a patient suffering from SCLC with a clinically relevant concentration shows the potential of the method in diagnosis, prognosis, and monitoring of the disease.
Using dual ring structure with different coupling ratio for S-band erbium-based fiber laser
Authors: Yeh C-H , Lee C-N , Shih F-Y , Chi S
Published: September 2007

An S-band erbium-doped fiber (EDF) ring laser, using a dual coupler ring structure (DCRS) with different coupling ratio injection, is proposed and demonstrated experimentally. The proposed fiber ring laser does not use any fiber Bragg gratings or etalon filters (passive or active filter) into the loop cavity to lase a single wavelength. This proposed fiber laser has an optical signal to noise ratio (OSNR) of > 38.2 dB and output power of - 3.8 dBm at 1506.28 nm, while the coupling ratio in a ring cavity is 10%. Moreover, the performances of output power and wavelength stabilities have also been studied and discussed.
Nature of refractive-index changes in diode pumped Yb:GGG crystal
Authors: Nikolaev D A , Seregin V F , Shcherbakov I A , Tsvetkov V B
Published: September 2007

The role of the electronic and thermal mechanisms to the process of refraction index changes in diode pumped Yb:GGG active disks have been studied while using highly sensitive interferometric technique. It was demonstrated that thermal and electronic components make comparable contributions to refraction index changes in Yb:GGG crystals under intensive pumping.
Effect of metal‐free phosphorus anti‐wear compounds on passenger car emissions and fuel economy
Authors: Devlin Mark T. , Guevremont Jeffrey , Sheets Roger , Loper John , Guinther Greg , Thompson Karen , Jao Tze‐Chi
Published: September 2007

There has been concern for many years that phosphorus (P) from engine oils is volatilised, passes through the combustion chamber and is deposited on the catalyst system in passenger cars, causing the emission control system to lose efficiency. Therefore, as new engine oil specifications have been introduced, there has been a trend to require a reduction in P in fresh engine oils. The primary P source in current engine oils is zinc dithiophosphate (ZDP), which acts as an anti‐wear agent and antioxidant. Therefore, a reduction in P in the oil could compromise the anti‐wear and antioxidant performance of engine oils. Another detrimental effect of ZDP is that it is known to increase friction in the mixed lubrication regime, which in turn would decrease the ability of engine oils to improve fuel economy. Metal‐free P‐containing anti‐wear additives (MFPAWs) have been used for many years in other automotive and industrial lubricants. We examined the effect of an MFPAW in catalyst efficiency and fuel economy engine tests. Catalyst protection and the fuel economy benefits of engine oils were improved when the MFPAW was used in place of ZDP. Therefore, the total P content of an engine oil does not need to be reduced if the proper anti‐wear additive is selected. Copyright © 2007 John Wiley & Sons, Ltd.
Microscopic characterization of collagen modifications induced by low‐temperature diode‐laser welding of corneal tissue
Authors: Matteini Paolo , Rossi Francesca , Menabuoni Luca , Pini Roberto
Published: September 2007

Background and Objective

Laser welding of corneal tissue that employs diode lasers (810 nm) at low power densities (12–20 W/cm2) in association with Indocyanine Green staining of the wound is a technique proposed as an alternative to conventional suturing procedures. The aim of this study is to evaluate, by means of light (LM) and transmission electron microscopy (TEM) analyses, the structural modifications induced in laser‐welded corneal stroma.

Materials and Methods

Experiments were carried out in 20 freshly enucleated pig eyes. A 3.5 mm in length full‐thickness cut was produced in the cornea, and was then closed by laser welding. Birefringence modifications in samples stained with picrosirius red dye were analyzed by polarized LM to assess heat damage. TEM analysis was performed on ultra‐thin slices, contrasted with uranyl acetate and lead citrate, in order to assess organization and size of type I collagen fibrils after laser welding.

Results

LM evidenced bridges of collagen bundles between the wound edges, with a loss of regular lamellar organization at the welded site. Polarized LM indicated that birefringence properties were mostly preserved after laser treatment. TEM examinations revealed the presence of quasi‐ordered groups of fibrils across the wound edges preserving their interfibrillar spacing. These fibrils appeared morphologically comparable to those in the control tissue, indicating that type I collagen was not denatured during the diode laser corneal welding.

Conclusions

The preservation of substantially intact, undenatured collagen fibrils in laser‐welded corneal wounds supported the thermodynamic studies that we carried out recently, which indicated temperatures below 66°C at the weld site under laser irradiation. This observation enabled us to hypothesize that the mechanism, proposed in the literature, of unwinding of collagen triple helixes followed by fibrils “interdigitation” is not likely to occur in the welding process that we set up for the corneal suturing. Lesers Surg. Med. 39:597–604, 2007. © 2007 Wiley‐Liss, Inc.
The anti‐inflammatory mechanism of 635 nm light‐emitting‐diode irradiation compared with existing COX inhibitors
Authors: Lim Wonbong , Lee SungGa , Kim Inae , Chung Mina , Kim Misook , Lim Hoisoon , Park Jinsoo , Kim Okjoon , Choi Hongran
Published: September 2007

Background and Objectives

Inhibition of cyclooxygenase (COX) and prostaglandin E2 (PGE2) protects cells against cell injury in specific pathophysiological situations: inflammation and oxidative stress. Although the anti‐inflammatory effects have been reported in clinical fields for specific wavelength irradiation during wound healing, the physiological mechanism has not been clarified yet. The aim of the present study is to investigate the anti‐inflammatory mechanism of 635 nm light‐emitting‐diode (LED) irradiation compared with existing COX inhibitors.

Study Design/Materials and Methods

The present study investigated anti‐inflammatory effects of 635 nm irradiation on PGE2 release, COX and phospholipase A2 (PLA2) expression, and reactive oxygen species (ROS) dissociation in arachidonic acid (AA)‐treated human gingival fibroblast (hGF). These results were compared with their existing COX inhibitors: indomethacin and ibuprofen. The PGE2 release was measured by enzyme immunoassay, the COX expression was measured by western blot and reverse transcriptase polymerase chain reaction (RT‐PCR), and ROS level was measured by flow cytometry, laser scanning confocal microscope and RT‐PCR.

Results

Results showed that 635 nm irradiation and existing COX inhibitors inhibit expression of COX and PGE2 release. Unlike indomethacin and ibuprofen, 635 nm irradiation leads to a decrease of ROS levels and mRNA expression of cytosolic phospholipase A2 (cPLA2) and secretary phospholipase A2 (sPLA2).

Conclusion

Taken together, 635 nm irradiation, unlike indomethacin and ibuprofen, can directly dissociate the ROS. This inhibits cPLA2, sPLA2, and COX expression, and results in the inhibition of PGE2 release. Thus, we suggest that 635 nm irradiation inhibits PGE2 synthesis like COX inhibitor and appears to be useful as an anti‐inflammatory tool. Lesers Surg. Med. 39:614–621, 2007. © 2007 Wiley‐Liss, Inc.
Interstitial photodynamic therapy for a symptom‐targeted treatment of complex vascular malformations in the head and neck region
Authors: Betz Christian S. , Jäger H. Rolf , Brookes Jocelyn A.S. , Richards Robin , Leunig Andreas , Hopper Colin
Published: September 2007

Background and Objectives

Photodynamic therapy is based on an interaction of a drug and light in oxygenated tissue. The photosensitizing drug Foscan® is licensed in the EU for the treatment of advanced head and neck cancer. The light can be applied by surface illumination or directly into tumour tissue by optical fibres. One interesting feature of PDT is that it does not cause major damage to nerves and major blood vessels. This raises the possibility of using this therapy in the treatment of benign neoplasms in the head and neck.

Study Design/Materials and Methods

A total of 11 patients with lymphatic [8] or venous malformation [3] were treated on 25 occasions. The treatments were carried out using Temoporphin (Foscan®) 0.15 mg/kg; the drug‐light‐interval was 4 days. Illumination was performed at 652 nm delivered interstitially through bare tip fibres at a total light dose of 20 J per fibre. Multiple fibres were positioned either image guided [13] or clinically [12] to ensure accurate targeting of tissue while avoiding damage of the surrounding and overlying tissue.

Results

In all cases there was a significant reduction in the volume of abnormal tissue without damage to the overlying skin; the results were objectified using MRI‐imaging, CT‐volumetry and surface optical scanning. The best results were obtained with lymphatic malformations, especially for those that had not undergone previous surgery. Post‐treatment pain and swelling were successfully controlled with steroids and a variety of analgesics (opioids and non‐steroidal anti‐inflammatories). No vascular or neurological signs were encountered.

Conclusion

This minimally invasive approach to treat complex benign neoplasias seems promising. The treatment is safe, effective and repeatable and merits further evaluation. Lesers Surg. Med. 39:571–582, 2007. © 2007 Wiley‐Liss, Inc.
Polyimide/Diamond Nanocomposites: Microstructure and Indentation Behavior
Authors: Zhang Qingxin , Naito Kimiyoshi , Tanaka Yoshihisa , Kagawa Yutaka
Published: September 2007

Polyimide/diamond nanocomposites have been synthesized from 4,4′‐diaminodiphenyl ether (ODA) and 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA). All the polyimides show non‐crystalline X‐ray diffraction. The frequent occurrence of particular interatomic distances (R) denoted by the non‐crystalline X‐ray diffraction maxima are determined. An ultramicro‐indentation technique is employed to evaluate the effects of nano‐diamond particles on the indentation behavior of polyimides. Indentation size effect is observed and discussed.

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Access to Poly{N‐[3‐(dimethylamino)propyl](meth)acrylamide} via Microwave‐Assisted Synthesis and Control of LCST‐Behavior in Water
Authors: Schmitz Sarah , Ritter Helmut
Published: September 2007

In the present paper, the microwave (MW)‐assisted synthesis of the alkaline N‐[3‐(dimethylamino)propyl]methacrylamide (4) and ‐acrylamide (5) monomers within minutes is described. The reaction was carried out by mixing and subsequent irradiation of 3‐dimethylamino‐1‐propylamine (3) and (meth)acrylic acid (1/2) without addition of solvent. After polymerization, the obtained homopolymers (6/7) exhibit lower critical solution temperature (LCST) behavior in water at 35 °C only at pH = 14. The LCST‐behavior can be influenced by N‐oxidation of the tertiary amino group with hydrogen peroxide or by formation of a polymer‐inclusion complex (6a) of 6 and β‐cyclodextrin (β‐CD) by addition of randomly‐methylated β‐CD.

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Role of vitamin A elimination or supplementation diets during postnatal development on the allergic sensitisation in mice
Authors: Rühl Ralph , Hänel Andrej , Garcia Ada L. , Dahten Anja , Herz Udo , Schweigert Florian J. , Worm Margitta
Published: September 2007

Vitamin A (VA) and its derivatives, the retinoids, are important factors for the development of the immune system. It has been shown in adult animals that proliferation of lymphocyte populations and antibody secretion are retinoid dependent, while little is known about the effects of retinoids during postnatal development. The aim of this study was to investigate the role of VA on allergic sensitisation during lactation and after weaning using an in vivo system for postnatal allergic sensitisation in mice. Different VA diets (basal/VA elimination/VA (as retinyl palmitate) supplemented) were fed to the dams throughout lactation and directly to the pups after weaning. Allergic sensitisation was induced with a single peritoneal ovalbumin (OVA) injection at day 28 after weaning. The phenotype of lymphocytes was analysed by flow cytometry and functional data were obtained by analysis of (IL‐4/IFN‐γ) cytokine production and antibody production (OVA‐specific IgG1 and IgE) in the offspring. VA/retinyl palmitate supplementation during lactation and after weaning decreased CD3+, CD4+, CD8+ and B220+ populations in splenic lymphocytes but also significantly enhanced IL‐4 production and OVA‐specific IgE after sensitisation. In contrast, mice fed VA‐elimination diet displayed no significant alteration of lymphocyte numbers and a slightly increased IL‐4 production. Our results showed that a single allergen injection during postnatal development induces allergic sensitisation whose degree is modified by the VA content of the maternal diet during lactation and the diet of the pups after weaning, indicating an important role of VA on the severity of the allergic sensitisation.
Expression of gonadotropin and gonadotropin receptor genes during early sexual maturation in male Atlantic salmon parr
Authors: Maugars Gersende , Schmitz Monika
Published: September 2007

Atlantic salmon males may mature already as small parr in freshwater. Sexual maturation in teleosts as in vertebrates is characterized by the activation of the brain–pituitary–gonad axis. The endocrine regulation of early puberty is still not well understood. In the present study, one‐summer‐old male Atlantic salmon parr were sampled regularly from December several months prior to the beginning of spermatogenesis until spawning in October. Pituitary expression levels of follicle‐stimulating hormone (FSH) and luteinizing hormone (LH) β subunit genes were analyzed in parallel with testis expression of FSH receptor (FSHR) and LH receptor (LHR) genes by RT‐PCR and plasma 11‐ketostestosterone (11‐KT) was measured. Expression levels of FSHβ, low during winter and spring started to increase prior to the onset of gonadal growth at the end of May while LHβ mRNA levels were hardly detectable. Both gonadotropin receptor genes were expressed in immature testis with FSHR transcripts being more abundant (8‐fold). FSHR transcript levels increased in parallel to FSHβ levels from early spermatogenesis onwards, while LHR mRNA started to increase prior to any large changes in LHβ expression. Both transcript levels of LHβ and LHR were highest during spermiation. Plasma 11‐KT increased at the beginning of spermatogenesis reaching highest levels at spermiogenesis suggesting a possible role of FSH in inducing 11‐KT production during early spermatogenesis while LH stimulates via its specific receptor 11‐KT production at spermiogenesis. The commitment into sexual maturation appears to be dependant on both the presence of FSHR in immature testis and the increase of FSH expression. Mol. Reprod. Dev. 75: 403–413, 2008. © 2007 Wiley‐Liss, Inc.
Osteopontin improves in vitro development of porcine embryos and decreases apoptosis
Authors: Hao Yanhong , Murphy Clifton N. , Spate Lee , Wax David , Zhong Zhisheng , Samuel Melissa , Mathialagan Nagappan , Schatten Heide , Prather Randall S.
Published: September 2007

An optimal environment for fertilization and early embryonic development is provided by the mammalian oviduct and uterus. The secretory cells lining the lumen of the oviduct and uterus synthesize and secrete proteins that have been shown to interact with and influence the activities of gametes and embryos. Western blotting in this study demonstrated that a 50‐kDa secreted phosphoprotein 1 (SPP1) form was present in the uterus on Days 0, 3, and 5 in pregnant and nonbred gilts, and the concentration of SPP1 on Day 0 was higher than on Days 3 and 5 in pregnant gilts, but in nonbred gilts the concentration of SPP1 on Day 0 was higher than Day 3, but not Day 5. In addition, we show that addition of 0.1 µg/ml SPP1 to the culture medium after fertilization increased the percent cleaved (24 hr: 23.6 ± 1.29a vs. 18.7 ± 0.65b (2‐cell %)), and the percent blastocyst (37.2 ± 1.12a vs. 30.9 ± 0.56b) derived from IVF (P < 0.05). In parthenogenetic‐derived embryos the percent cleaved was increased due to SPP1 at 24 hr (24.0 ± 1.59a vs. 19.7 ± 1.59b (>2‐cell %)), and at 48 hr (72.9± 2.99a vs. 63.3 ± 2.99b), but not the percent blastocyst. By TUNEL assay, SPP1 decreased both apoptosis (7.9 ± 0.04a vs. 13.1 ± 0.02b) and the percent fragmentation (45.2  ± 0.07a vs. 58.8  ± 0.03b). We conclude that SPP1 can improve development in vitro possibly by reducing the rate of apoptosis. Mol. Reprod. Dev. 75: 291–298, 2008. © 2007 Wiley‐Liss, Inc.
Cryogenic effect of antifreeze protein on transgenic mouse ovaries and the production of live offspring by orthotopic transplantation of cryopreserved mouse ovaries
Authors: Bagis Haydar , Akkoç Tolga , Tasş Arzu , Aktoprakligil Digdem
Published: September 2007

The purpose of the present study was to evaluate the cryogenic effect of antifreeze protein (AFP) on transgenic mouse ovaries which is expressed AFP type III from Ocean pout and the production of live offspring by orthotopic transplantation of cryopreserved mouse ovaries. In this study, whole transgenic and nontransgenic mouse ovaries were vitrified with 20% DMSO and 20% EG in M2 medium supplemented with 0.5 M sucrose. All vitrified and toxicity control and fresh ovaries were transplanted orthotopically into ovariectomized recipients bilaterally. For fresh ovaries transplantation, 5 mice delivered litters of 18 and 19 live pups in first and second matings, respectively. For toxicity control of chemicals, 6 mice delivered litters of 22 and 23 live pups. For nontransgenic mouse ovaries (vitrified) transplantation, 7 mice delivered litters of 22 and 23 live pups. For transgenic mouse ovaries (vitrified) transplantation, 10 mice delivered litters of 35 and 37 live pups. Litter sizes from pups of freshly transplanted ovaries were not significantly different from AFP‐transplanted transgenic ovaries but those from nontransgenic‐transplanted ovaries were significantly different from the AFP‐transplanted transgenic ovaries group (P < 0.05). In this study, for the first time, it was shown that the ovarian tissue of AFP transgenic mice was protected from cryopreservation by vitrification. These results demonstrate that a normal reproductive lifespan can be restored by orthotopic transplantation of AFP transgenic‐vitrified ovary. Mol. Reprod. Dev. 75: 608–613, 2008. © 2007 Wiley‐Liss, Inc.
Expression of the vascular endothelial growth factor‐receptor system in the porcine endometrium throughout the estrous cycle and early pregnancy
Authors: Kaczmarek Monika M. , Waclawik Agnieszka , Blitek Agnieszka , Kowalczyk Anna E. , Schams Dieter , Ziecik Adam J.
Published: September 2007

The objective of this study was to investigate the protein and mRNA expression of vascular endothelial growth factor (VEGF), VEGFR‐1 (fms‐like tyrosine kinase, Flt‐1) and VEGFR‐2 (fetal liver kinase‐1/kinase insert domain‐containing receptor, Flk‐1/KDR) in the endometrium during the estrous cycle and early pregnancy in pigs. The VEGF‐receptor system was localized in epithelial and stromal cells, blood vessels, and myometrium. Western blot analysis showed higher levels of VEGF protein during the periovulatory and periimplantation periods (P < 0.001, and P < 0.05, respectively). Constant expression of VEGF mRNA during the cycle and significant upregulation on Days 22–25 of gestation (vs. Days 9–17; P < 0.001) was observed. Stable levels of VEGFR‐1 mRNA and protein were detected in the endometrium of cyclic animals. However, higher VEGFR‐1 protein expression was found on Days 16–17 of the estrous cycle (P < 0.01) and Days 13–15 of gestation (P < 0.05). Protein expression of VEGFR‐2 was elevated on Days 2–4 of the estrous cycle (P < 0.001), but mRNA levels were constant during the cycle. In pregnancy, VEGFR‐2 protein expression started to increase after Day 15 (vs. Days 9–12; P < 0.05), but induction of VEGFR‐2 mRNA expression occurred earlier on Days 13–15. It appears from the present study that the VEGF‐receptor system is regulated in a temporal and spatial manner during the estrous cycle and early pregnancy in pigs. The results suggest that VEGF‐A family members are probably involved in appropriate preparation of endometrium for implantation and in vascular events during implantation in pigs. Mol. Reprod. Dev. 75: 362–372, 2008. © 2007 Wiley‐Liss, Inc.
Production of quail (Coturnix japonica) germline chimeras derived from in vitro‐cultured gonadal primordial germ cells
Authors: Park Tae Sub , Kim Mi A , Lim Jeong Mook , Han Jae Yong
Published: September 2007

A previous report from our laboratory documented successful production of quail (Coturnix japonica) germline chimeras by transfer of gonadal primordial germ cells (gPGCs). Subsequently, this study was designed to evaluate whether gPGCs can be maintained in vitro for extended period, and furthermore, these cultured PGCs can induce germline transmission after transfer into recipient embryos. In experiment 1, gonadal cells from the two strains (wild‐type plumage (WP) and black (D) quail) were cultured in vitro for 10 days. Using antibody QCR1, we detected a continuous, significant (P = 0.0002) increase in the number of WP, but not D, PGCs. QCR1‐positive WP colonies began to form after 7 days in culture. On Day 10 of culture, 803 WP PGCs were present as a result of a continuous increase, whereas no D PGC colonies could be detected and the D gonadal stroma cells were rolled up. Differences in the PGCs or the gonadal stroma cells of the two different strains might account for these differences. In experiment 2, WP PGC colonies were maintained in vitro up to Day 20 of culture, and 10‐ or 20‐day‐cultured PGCs were microinjected into dorsal aortas of 181 recipient D embryos. Thirty‐five (19.3%) of the transplanted embryos hatched after incubation, and 25 (71.4%) of the hatchlings reached sexual maturity. Testcrossing of the sexually mature hatchlings resulted in three (10 days, 33.3%) and eight (20 days, 50.0%) germline chimeras respectively. This report is the first to describe successful production of germline chimera by transfer of in vitro‐cultured gPGCs in quail. Mol. Reprod. Dev. 75: 274–281, 2008. © 2007 Wiley‐Liss, Inc.
Estimation of effective stress parameter of unsaturated soils by using artificial neural networks
Authors: Kayadelen C.
Published: September 2007

Great efforts are required for determination of the effective stress parameter χ, applying the unsaturated testing procedure, since unsaturated soils that have the three‐phase system exhibit complex mechanical behavior. Therefore, it seems more reasonable to use the empirical methods for estimation of χ. The objective of this study is to investigate the practicability of using artificial neural networks (ANNs) to model the complex relationship between basic soil parameters, matric suction and the parameter χ. Five ANN models with different input parameters were developed. Feed‐forward back propagation was applied in the analyses as a learning algorithm. The data collected from the available literature were used for training and testing the ANN models. Furthermore, unsaturated triaxial tests were carried out under drained condition on compacted specimens. ANN models were validated by a part of data sets collected from the literature and data obtained from the current study, which were not included in the training phase. The analyses showed that the results obtained from ANN models are in satisfactory agreement with the experimental results and ANNs can be used as reliable tool for prediction of χ. Copyright © 2007 John Wiley & Sons, Ltd.
Chemical speciation by selective heteronuclear single‐quantum coherence spectroscopy: determination of double‐bond quantity in unsaturated fatty acid compounds
Authors: Tesiram Yasvir A. , Saunders Debra , Towner Rheal A.
Published: September 2007

A method for identifying fatty acid species based on the number of double bonds contained in a lipid molecule is presented. Common to all polyunsaturated fatty acids are two signature resonances at ∼5.3 and 2.8 ppm in the proton chemical‐shift spectrum of NMR. These resonances are from the vinyl and bis‐allyl protons, respectively, and, although they can be readily observed by NMR from lipid extracts of biological samples, direct speciation has never been demonstrated by NMR. By modifying a conventional HSQC pulse sequence with a J‐pulse on the spin system of the vinyl group (generalized as an IS spin system) at the beginning of the initial polarization transfer period and selectively inverting the 13C (I) spins with a narrowband sech/tanh inversion pulse, the collection of data in both dimensions can be restricted to a narrow slice of the chemical‐shift range. The resolution is subsequently determined by digitizer efficiency, and spectra can be collected optimally from within a very narrow 1 × 6 ppm window of the respective proton and carbon chemical‐shift ranges. With this modification it is possible to distinguish at least one resonance each from the multiple shifts expected from the indirectly detected nuclei of the fatty acid species, oleic acid, linoleic acid, linolenic acid and arachidonic acid, which contain one, two, three and four double bonds, respectively. This and similar methods of applied selectivity are of potential interest in characterizing speciation in biological samples where mixtures are often encountered and chemical shifts of the same structural group of similar molecules give rise to complicated overlapping resonances but are important for diagnosis of disease processes such as cancer. Copyright © 2007 John Wiley & Sons, Ltd.
Effects of shadowing on photovoltaic module performance
Authors: Silvestre S. , Chouder A.
Published: September 2007

A procedure of simulation and modelling PV modules' performance, working partially shadowed, is presented. Several shadow rates have been tested on a single cell forming part of a PV module having 36 solar cells serially connected, and the influence of shadow rate in most of the important PV module characteristic parameters has been evaluated.The correlation between PV module output lowering due to shadowing and the variation of resistive losses is also reported. Copyright © 2007 John Wiley & Sons, Ltd.
A computational study into the reactivity of epichlorohydrin and epibromohydrin under acidic conditions in the gas phase and aqueous solution
Authors: Shields E. S. , Merrill G. N.
Published: September 2007

Ab initio molecular orbital calculations have been carried out upon epichlorohydrin and epibromohydrin at the Hartree–Fock (HF) and Møller–Plesset (MP2) levels of theory to explore the reactivity of these species with respect to nucleophilic attack by water under acidic conditions in the gas phase and aqueous solution. These results suggest that nucleophilic attack occurs preferentially at the epoxy carbon atoms in both the gas phase and aqueous solution. These results are in contrast to those found for nucleophilic attack under basic conditions, where attack at the halocarbon atom is competitive with that at the epoxy carbon atoms. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and optical properties of fluorene‐based polymers incorporating organosilicon unit
Authors: Takagi Koji , Kakiuchi Hiroki , Yuki Yasuo , Suzuki Masato
Published: September 2007

The synthesis and optical properties of polymers bearing the repeating unit of terfluorene and various organosilicon groups were investigated. Polymers with high molecular weight and good solubility could be obtained by Suzuki coupling polymerization from silylene‐containing fluorene‐based dibromo monomers and 9,9‐dihexylfluorene‐2,7‐bis(trimethyleneborate). From UV spectra of polymers bearing acyclic silylene bridge, the organosilicon units not only interrupted a π‐conjugation but also contributed to an electronic communication between connected fluorenes. The emission maximum wavelengths (ca. 400 nm) blue‐shifted when compared with that of polyfluorene (418 nm) and the fluorescence quantum yields were considerably high (>0.82) in the CHCl3 solution. On the other hand, rather broad emission was observed at 480 nm and the fluorescence quantum yield was quite low (0.004) in the solution‐state PL spectrum of tetraphenylsilole‐containing polymer. The polymer emitted visible green light in the spin‐coated film. The fluorescence peak intensity at 486 nm gradually decreased when the film was illuminated with the UV light of 359 nm in air. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4786–4794, 2007
Synthesis of ABCD‐type miktoarm star copolymers and transformation into zwitterionic star copolymers
Authors: Wang Xiaojun , He Junpo , Yang Yuliang
Published: September 2007

ABCD‐type 4‐miktoarm star copolymers of styrene (St), α‐methylstyrene (αMSt), tert‐butyl methacrylate (tBuMA), and 4‐vinylpyridine (4VP) were synthesized via anionic polymerization using 1,3‐bis(1‐phenylvinyl)benzene (m‐DDPE) as the linking molecule. The synthetic route was rationally designed with respect to the reactivity of individual propagating anion towards the double bond of m‐DDPE. Thus the synthesis includes several consecutive key reactions, for example, the monoaddition of polystyryllithium towards m‐DDPE, the polymerization of tBuMA initiated by the resulting monoadduct to produce a diblock macromonomer, the coupling of the macromonomer with poly(α‐methylstyryl)lithium to form a 3‐arm star anion, and the polymerization of 4‐vinylpyridine initiated by the star anion. These reactions were conducted either in a one‐pot process, in which the diblock macromonomer was in situ coupled with poly(α‐methylstyryl)lithium, or in a batch polymerization process, in which the same diblock macromonomer was separated. The final product was hydrolyzed to produce a zwitterionic miktoarm star copolymer, which was soluble at lower pH but insoluble in neutral and basic solution. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4818–4828, 2007
Segmented sulfonated poly(arylene ether sulfone)‐b‐polyimide copolymers for proton exchange membrane fuel cells. I. Copolymer synthesis and fundamental properties
Authors: Lee Hae‐Seung , Badami Anand S. , Roy Abhishek , McGrath James E.
Published: September 2007

Segmented disulfonated poly(arylene ether sulfone)‐b‐polyimide copolymers based on hydrophilic and hydrophobic oligomers were synthesized and evaluated for use as proton exchange membranes (PEMs). Amine terminated sulfonated poly (arylene ether sulfone) hydrophilic oligomers and anhydride terminated naphthalene based polyimide hydrophobic oligomers were synthesized via step growth polymerization including high temperature one‐pot imidization. Synthesis of the multiblock copolymers was achieved by an imidization coupling reaction of hydrophilic and hydrophobic oligomers oligomers in a m‐cresol/NMP mixed solvent system, producing high molecular weight tough and ductile membranes. Proton conductivities and water uptake increased with increasing ion exchange capacities (IECs) of the copolymers as expected. The morphologies of the multiblock copolymers were investigated by tapping mode atomic force microscopy (TM‐AFM) and their measurements revealed that the multiblock copolymers had well‐defined nano‐phase separated morphologies which were clearly a function of block lengths. Hydrolytic stability test at 80 °C water for 1000 h showed that multiblock copolymer membranes retained intrinsic viscosities of about 80% of the original values and maintained flexibility which was much improved over polyimide random copolymers. The synthesis and fundamental properties of the multiblock copolymers are reported here and the systematic fuel cell properties will be provided in a separate article. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4879–4890, 2007
Effect of supercritical carbon dioxide on the crystallization behavior of poly(ether ether ketone)
Authors: Wang Dong , Gao Hong , Jiang Wei , Jiang Zhenhua
Published: September 2007

The supercritical CO2 (sc‐CO2) provided a moderate condition to make the amorphous CO2/poly(ether ether ketone) (PEEK) mixtures at 30 MPa and 40 °C. The crystal is obtained directly after treating CO2/PEEK mixture from 70 to 240 °C. The crystallization behavior of CO2/PEEK mixtures before and after treatment is investigated in detail by using differential scanning calorimetry (DSC), dynamic mechanical analysis, and wide‐angle X‐ray diffraction. DSC curves of CO2/PEEK samples showed the double cold crystallization peaks. The lower cold crystallization peak moves to higher temperature with the content of CO2 decreasing, and the higher cold crystallization peak keeps their temperatures at about 172 °C without a remarkable change. The dynamic mechanical spectrometry was also introduced to explain the relaxation behavior of the glass transition and crystallization. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2927–2936, 2007
Near‐optimum short‐term fade prediction on satellite links at Ka and V‐bands
Authors: Chambers Andrew P. , Otung Ifiok E.
Published: September 2007

Several short‐term predictors of rain attenuation are implemented and tested using data recorded from a satellite link in Southern England, and a comparison is made in terms of the root‐mean‐square error and the cumulative distribution of under‐predictions. A hybrid of an autoregressive moving average and adaptive linear element predictor is created that makes use of Gauss–Newton and gradient direction coefficient updates and exhibits the best prediction error performance of all prediction methods in the majority of cases. Copyright © 2007 John Wiley & Sons, Ltd.
Procedural fairness and interfirm cooperation in strategic alliances
Authors: Luo Yadong
Published: September 2007

This study applies the justice theory to address interpartner cooperation in strategic alliances. It emphasizes how procedural fairness as perceived by boundary spanners in these alliances influences cooperation outcomes. We theorize that procedural fairness improves cooperation results through enhancing relational value and curtailing relational risk in an environment characterized by both economic and social exchange. Our path analysis suggests that procedural fairness has a direct effect on operational outcome, but an indirect effect on financial outcome via increased trust driven by fairness. Procedural fairness contributes more to performance outcomes when strategic alliances are equity joint ventures than if they are contractual agreements. Theoretical and managerial implications arising from the findings are highlighted. Copyright © 2007 John Wiley & Sons, Ltd.
Toward an integrative cartography of two strategic issue diagnosis frameworks
Authors: Julian Scott D. , Ofori‐Dankwa Joseph C.
Published: September 2007

There exist two prominent accounts of how managers make sense of and take action in relation to strategic issues. The threat–opportunity (TO) and feasibility–urgency (FU) approaches primarily emphasize automatic/affective and active/deliberative strategic issue diagnosis processes, respectively. Current research, however, does not effectively integrate or fully explore the relationship between these two frameworks. We employ theory‐building literature to develop a framework that highlights four distinct and increasingly integrative lenses through which such an exploration can be systematically carried out. Analyzing data from how firms reacted to the economic uncertainty of early 2003, the results of our study indicate that the FU approach is a better predictor of both intentions and actual responses than the TO approach. Our results also indicate that threat is positively related to urgency and negatively related to feasibility, while opportunity is positively related to feasibility and negatively related to urgency. Further, using the expectancy–instrumentality–valence (EIV) motivational theory as a framework, we factor analyze both TO and FU items, identifying three underlying constructs of favorability, urgency, and influence (which we dub FUI). FUI has a higher predictive efficacy than the TO approach alone. We highlight implications for theory building and research in the strategic issue diagnosis literature. Copyright © 2007 John Wiley & Sons, Ltd.
The history and impact of state initiatives to eliminate affirmative action
Authors: Kaufmann Susan W.
Published: September 2007

As diversity increases in the general population, U.S. colleges and universities are struggling to maintain campus diversity in the context of legislative elimination of affirmative action in admissions.
Interactive theater and self‐efficacy
Authors: Burgoyne Suzanne , Placier Peggy , Thomas Mallory , Welch Sharon , Ruffin Clyde , Flores Lisa Y. , Celebi Elif , Azizan‐Gardner Noor , Miller Marilyn
Published: September 2007

What are the advantages and drawbacks of using inter‐active theater for faculty development on multicultural issues?
Multicultural teaching and learning resources for preparing future faculty in teaching in higher education courses
Authors: Alexander Ilene D. (Ida)
Published: September 2007

The author provides a review of readings from which future faculty might explore and begin to shape a multicultural approach to teaching and learning.
Intergroup dialogue: A critical‐dialogic approach to learning about difference, inequality, and social justice
Authors: Nagda Biren (Ratnesh) A. , Gurin Patricia
Published: September 2007

The authors describe and evaluate an approach to engaging students in exploring social identities, understanding inequality, and identifying avenues for individual and collective action for greater social justice.
New learning and teaching from where you've been: The global intercultural experience for undergraduates
Authors: Miller A. T. , Fernández Edith
Published: September 2007

The authors describe the structure and impact of faculty‐led intercultural field placements involving diverse groups of students.
Diversity and retention in engineering
Authors: Davis Cinda‐Sue G. , Finelli Cynthia J.
Published: September 2007

The authors describe three initiatives designed to increase the academic achievement and retention of historically underrepresented students (including females and underrepresented students of color) in engineering.
Singing down the barriers: Encouraging singers of all racial backgrounds to perform music by African American composers
Authors: Helton Caroline , Stephens Emery
Published: September 2007

This chapter investigates the barriers faced by singers of all racial backgrounds when performing spirituals and African American art songs and suggests ways to eliminate those barriers.
Diversity education and identity development in an information technology course
Authors: Trauth Eileen M. , Johnson R. Neill , Morgan Allison , Huang Haiyan , Quesenberry Jeria
Published: September 2007

This chapter offers an example of a discipline‐specific approach to diversity education and its impact on student learning.
Simulations and the dynamics of racial and gender gaps in civic competence
Authors: Bernstein Jeffrey L.
Published: September 2007

This chapter discusses the benefits and constraints of a simulation‐based strategy for enhancing civic competence among introductory government students, an approach that shows promise for closing racial and gender gaps in political efficacy and participation.
Infusing mathematics with culture: Teaching technical subjects for social justice
Authors: Winter Dale
Published: September 2007

How can disciplines that are commonly regarded as culturally neutral be taught in ways that connect technical content with social and cultural issues?
Lifetime‐maximized cluster association in two‐tiered wireless sensor networks
Authors: Song Wen‐Zhan , Wang WeiZhao , Moaveni‐Nejad Kousha , Li Xiang‐Yang
Published: September 2007

In this paper, we study the two‐tiered wireless sensor network (WSN) architecture and propose the optimal cluster association algorithm for it to maximize the overall network lifetime. A two‐tiered WSN is formed by number of small sensor nodes (SNs), powerful application nodes (ANs), and base‐stations (BSs, or gateways). SNs capture, encode, and transmit relevant information to ANs, which then send the combined information to BSs. Assuming the locations of the SNs, ANs, and BSs are fixed, we consider how to associate the SNs to ANs such that the network lifetime is maximized while every node meets its bandwidth requirement. When the SNs are homogeneous (e.g., same bandwidth requirement), we give optimal algorithms to maximize the lifetime of the WSNs; when the SNs are heterogeneous, we give a 2‐approximation algorithm that produces a network whose lifetime is within 1/2 of the optimum. We also present algorithms to dynamically update the cluster association when the network topology changes. Numerical results are given to demonstrate the efficiency and optimality of the proposed approaches. In simulation study, comparing network lifetime, our algorithm outperforms other heuristics almost twice. Copyright © 2007 John Wiley & Sons, Ltd.
Background of x‐ray nanophotonics based on the planar air waveguide resonator
Authors: Egorov V. K. , Egorov E. V.
Published: September 2007

The work elucidates some model details of x‐ray flux waveguide resonance propagation through a planar, narrow, extended slit. The phenomenological substantiation of the correctness of the introduction of the waveguide resonance model is confirmed on the basis of the concept of flux spatial coherence. The peculiarities of the model realization in various designs of planar x‐ray waveguide resonators (PXWR) are discussed. The main fields of practical application of PXWRs are characterized by experimental results. Nanophotonics perspectives using waveguide resonance structures are outlined. Copyright © 2007 John Wiley & Sons, Ltd.
In vivo x‐ray fluorescence analysis (XRF) of the thyroid iodine content—Influence of measurement geometries on the iodine Kα signal
Authors: Hansson M. , Berg G. , Isaksson M.
Published: September 2007

The thyroid gland is unique in that it stores a large amount of iodine, an element suitable for x‐ray fluorescence analysis (XRF). Knowledge of the amount of iodine stored in the thyroid in the iodine pool may contribute to the understanding of thyroid diseases and possibly predict treatment outcome. XRF is a non‐invasive method which can be used for direct evaluations of the iodine pool in vitro as well as in vivo. However, in contrast to in vitro studies, which involve a measurement geometry that is well known and can be carefully controlled, complications may arise when using the technique in vivo. In this study, Monte Carlo (MC) simulations were used for finding an optimal measurement geometry regarding source and detector collimator apertures. The relative importance of primary and scattered radiation in the production of iodine Kα x‐rays for a simulated thyroid gland at different depths in the neck was investigated. The results showed that incoherently scattered radiation may be a considerable contributor of Kα photons in commonly encountered in vivo geometries. Calibrations should thus be performed with precise knowledge of the measurement geometry and it is important that corrections are made for primary photon fluence but also for photon scattering in the neck. Copyright © 2007 John Wiley & Sons, Ltd.