bluuebunny/crossref_metadata_2025 huggingface dataset:
Aspects of fishing and reproduction of the black grouper Mycteroperca bonaci (Poey, 1860) (Serranidae: Epinephelinae) in the Northeastern Brazil
Authors: Teixeira Simone Ferreira , Ferreira Beatrice Padovani , Padovan Isaíras Pereira
Published: January 2008

The reproductive biology of the black grouper Mycteroperca bonaci, caught by artisanal fishermen using hook and line or compressor - assisted spear fishing, from the Northeastern shelf and oceanic banks of Brazil, was studied between August 1996 and April 1998. The sexual pattern, gonadal development, the spawning mode and seasonality were investigated. The gonadal stages indicated that this species is a protogynous hermaphrodite and that transition from female to male occurs through simultaneous re-absorption of ovarian tissue and proliferation of testicular tissue in the gonads. The specie is a multiple spawner and frequency analysis of gonadal stages and gonadosomatic index suggest that the spawning season occurs between April and September. Considerations about the fisheries, related to size structure of fishes caught, were based on length frequency distribution. The phenomenon of "correção" was described based on ethnobiology studies and informations from the Northeast Fisheries Statistics Bulletin of the Brazilian Environmental Institute (IBAMA). The phenomenon of the "correção" undergone by Mycteroperca bonaci seems to be a Southward chain reaction (of the State of Ceará to Bahia) and is a feeding aggregation.
Two new species of Bryconamericus Eigenmann (Characiformes: Characidae) from southern Brazil
Authors: Silva José Francisco Pezzi da
Published: January 2008

Two new species of Bryconamericus are described from southern Brazil: B. patriciae, from the headwaters of rio Pelotas (rio Uruguay drainage) and rio das Antas (laguna dos Patos drainage) and B. ecai from lower rio Taquari drainage. Bryconamericus patriciae differs from other Bryconamericus species from southern South America, by the following combination of characters: body depth (25.5-30.3% SL); head length (25.2-27.6% SL); pelvic-fin length (11.0-14.4% SL); branched anal-fin rays 14-18; teeth of outer row of premaxilla regularly implanted; teeth of inner row of premaxilla pentacuspid; teeth compressed distally; and males with bony hooks on pelvic and anal fins. Bryconamericus ecai differs from other Bryconamericus species from southern South America by the following combination of characters: body depth (33.1-36.9% SL); eye diameter (31.1-33.9% HL); snout length (26.8-32.4% HL); branched anal-fin rays 15-18; teeth of outer row of premaxilla regularly implanted; teeth of inner row of premaxilla tricuspid or pentacuspid; teeth compressed distally; and males with bony hooks on pelvic and anal fins.
Diet and dental development of three species of Roeboides (Characiformes: Characidae)
Authors: Novakowski Gisele Caroline , Fugi Rosemara , Hahn Norma Segatti
Published: January 2008

Lepidophagy has been recorded in various species of Roeboides. In this study we analyzed ontogenetic variation in diet and dental development of three Roeboides species (R. paranensis, R. prognathus and R. microlepis). Roeboides paranensis consumed mainly insects, scales and microcrustaceans, and the smaller individuals (<3.4 cm - SL) consumed mostly insects. Scale were only consumed by individuals greater than 3.4 cm. Scales were the dominant item in the diet in all sizes of R. prognathus. The diet of R. microlepis was composed primarily of whole fishes, however, the smaller individuals (<5.4 cm) consumed only insects. During ontogeny, exterior migration of teeth in the mouth started at 3.7 cm in R. paranensis and 6.5 cm in R. microlepis. As body length increased more teeth migrated exteriorly. This leads to greater consumption of scales by three species. Roeboides prognathus appeared to be most specialized on scales, since they composed 80% of the diet, and was the species with the highest number of external teeth and the most developed.
Courtship behavior and spawning of the hairy blenny Labrisomus nuchipinnis (Labrisomidae) in southeastern Brazil
Authors: Gibran Fernando Zaniolo , Santos Flávia Borges , Santos Hertz Figueiredo dos , Sabino José
Published: January 2008

Labrisomus nuchipinnis is a diurnal bottom-dwelling sit-and-wait carnivorous fish that inhabits holes and rifts of rocky areas in tropical shallow waters. Here we report on the courtship behavior and spawning of this hairy blenny in southeastern Brazil, with a detailed description and comparison with other Blennioidei. Labrisomus nuchipinnis is a territorial species that was observed courting with more than one female, and presenting a well defined pattern cycle related to reproductive behavior and paternal egg care. Adhesive demersal eggs are laid on small algae-covered rocks at sites with increased current velocity within the male's territory, which may enable higher egg survivorship and shorter developmental time.
Catfishes of the genus Auchenipterichthys (Osteichthyes: Siluriformes: Auchenipteridae): a revisionary study
Authors: Ferraris Jr. Carl J. , Vari Richard P. , Raredon Sandra J.
Published: January 2008

The Neotropical auchenipterid catfish genus Auchenipterichthys is reviewed and found to include four species. Auchenipterichthys thoracatus, formerly considered to be widely distributed throughout the Amazon River basin, is found to be restricted to the upper Madeira River basin. The widespread Amazonian species that had been misidentified as A. thoracatus is, instead, A. coracoideus; a species that also occurs in the upper Essequibo River. Auchenipterichthys longimanus, the most widely distributed species of the genus, is found through much of the Amazon and Orinoco River basins. The fourth species of the genus, A. punctatus (and its junior synonym A. dantei), is found in the upper portions of the Orinoco and Negro River basins in Venezuela and the central portions of the Amazon River basin in Brazil. All four species of Auchenipterichthys are redescribed and illustrated, and a key to the species is provided.
An albino armored catfish Schizolecis guntheri (Siluriformes: Loricariidae) from an Atlantic Forest coastal basin
Authors: Brito Marcelo F. G. de , Caramaschi Érica P.
Published: January 2008

We report here on an albino specimen of Schizolecis guntheri caught in the rio Bonito in the rio Macaé basin, Rio de Janeiro State, southeastern Brazil. The hypothesis that albinism is more common in fishes with cryptobiotic and/or nocturnal habits is strengthened by additional records of this chromatic anomaly.
Aerobic and Anaerobic Transformations of Sulfide in a Sewer System—Field Study and Model Simulations
Authors: Nielsen Asbjørn Haaning , Vollertsen Jes , Jensen Henriette Stokbro , Madsen Heidi Ina , Hvitved‐Jacobsen Thorkild
Published: January 2008

The formation and fate of sulfide in a force main and a downstream‐located gravity sewer were investigated in an extensive field study. Sulfide formation in the force main was significant. However, during 14 minutes of transport in the gravity sewer, the sulfide concentration decreased 30%, on average. An application of a conceptual sewer process model for simulating the formation and fate of sulfide was demonstrated. Overall, the model predicted that approximately 90% of the decrease of the sulfide concentration in the gravity sewer was the result of sulfide oxidation and that only a small fraction entered the sewer atmosphere, causing odor and corrosion. Even so, the model predicted concrete corrosion rates of up to 1.2 mm/y in the gravity sewer section.
Development and Demonstration of a Free Surface Flow‐Dependent Sampling Technology
Authors: Daas Mutaz , Srivastava Rajiv , Retnaswamy Ashok
Published: January 2008

Statistical assessment of water quality data, obtained at the South Florida Water Management District (West Palm Beach, Florida) S‐65E structure, illustrated significant differences and inconsistency in nutrient concentrations (Daas and Ebadian, 2003). The evaluation showed that currently used water sampling techniques are inadequate because of deficiencies in functionality and sensitivity to flow conditions at the structure. Moreover, the study indicated the need for a more precise sampling technology, which would consider variations in the velocity profile across the water column during the sampling process.     Therefore, a new prototype sampling technology was designed and tested in a pilot open channel. The new sampler had the capability to collect discrete aliquot volumes of water samples that are proportional to the corresponding point velocity at each of these depths. The discrete aliquot volumes were blended to provide an integrated sample that captures the variations in the velocity profile.
Inhibition of Foxo1 Protects Pancreatic Islet β-Cells Against Fatty Acid and Endoplasmic Reticulum Stress–Induced Apoptosis
Authors: Martinez Sara C. , Tanabe Katsuya , Cras-Méneur Corentin , Abumrad Nada A. , Bernal-Mizrachi Ernesto , Permutt M. Alan
Published: January 2008

OBJECTIVE—β-Cells are particularly susceptible to fatty acid–induced apoptosis associated with decreased insulin receptor/phosphatidylinositol-3 kinase/Akt signaling and the activation of stress kinases. We examined the mechanism of fatty acid–induced apoptosis of mouse β-cells especially as related to the role played by endoplasmic reticulum (ER) stress–induced Foxo1 activation and whether decreasing Foxo1 activity could enhance cell survival.

RESEARCH DESIGN AND METHODS—Mouse insulinoma (MIN6) cells were administered with fatty acids, and the role of Foxo1 in mediating effects on signaling pathways and apoptosis was examined by measuring Foxo1 activity and using dominant-negative Foxo1.

RESULTS—Increasing fatty acid concentrations (100–400 μmol/l palmitate or oleate) led to early Jun NH2-terminal kinase (JNK) activation that preceded induction of ER stress markers and apoptosis. Foxo1 activity was increased with fatty acid administration and by pharmacological inducers of ER stress, and this increase was prevented by JNK inhibition. Fatty acids induced nuclear localization of Foxo1 at 4 h when Akt activity was increased, indicating that FoxO1 activation was not mediated by JNK inhibition of Akt. In contrast, fatty acid administration for 24 h was associated with decreased insulin signaling. A dominant-negative Foxo1 adenovirus (Adv-DNFoxo) conferred cells with protection from ER stress and fatty acid–mediated apoptosis. Microarray analysis revealed that fatty acid induction of gene expression was in most cases reversed by Adv-DNFoxo, including the proapoptotic transcription factor CHOP (C/EBP [CCAAT/enhancer binding protein] homologous protein).

CONCLUSIONS—Early induction of JNK and Foxo1 activation plays an important role in fatty acid–induced apoptosis. Expressing a dominant-negative allele of Foxo1 reduces expression of apoptotic and ER stress markers and promotes β-cell survival from fatty acid and ER stress, identifying a potential therapeutic target for preserving β-cells in type 2 diabetes.
mTOR Inhibition by Rapamycin Prevents β-Cell Adaptation to Hyperglycemia and Exacerbates the Metabolic State in Type 2 Diabetes
Authors: Fraenkel Merav , Ketzinel-Gilad Mali , Ariav Yafa , Pappo Orit , Karaca Melis , Castel Julien , Berthault Marie-France , Magnan Christophe , Cerasi Erol , Kaiser Nurit , Leibowitz Gil
Published: January 2008

OBJECTIVE—Mammalian target of rapamycin (mTOR) and its downstream target S6 kinase 1 (S6K1) mediate nutrient-induced insulin resistance by downregulating insulin receptor substrate proteins with subsequent reduced Akt phosphorylation. Therefore, mTOR/S6K1 inhibition could become a therapeutic strategy in insulin-resistant states, including type 2 diabetes. We tested this hypothesis in the Psammomys obesus (P. obesus) model of nutrition-dependent type 2 diabetes, using the mTOR inhibitor rapamycin.

RESEARCH DESIGN AND METHODS—Normoglycemic and diabetic P. obesus were treated with 0.2 mg · kg−1 · day−1 i.p. rapamycin or vehicle, and the effects on insulin signaling in muscle, liver and islets, and on different metabolic parameters were analyzed.

RESULTS—Unexpectedly, rapamycin worsened hyperglycemia in diabetic P. obesus without affecting glycemia in normoglycemic controls. There was a 10-fold increase of serum insulin in diabetic P. obesus compared with controls; rapamycin completely abolished this increase. This was accompanied by weight loss and a robust increase of serum lipids and ketone bodies. Rapamycin decreased muscle insulin sensitivity paralleled by increased glycogen synthase kinase 3β activity. In diabetic animals, rapamycin reduced β-cell mass by 50% through increased apoptosis. Rapamycin increased the stress-responsive c-Jun NH2-terminal kinase pathway in muscle and islets, which could account for its effect on insulin resistance and β-cell apoptosis. Moreover, glucose-stimulated insulin secretion and biosynthesis were impaired in islets treated with rapamycin.

CONCLUSIONS—Rapamycin induces fulminant diabetes by increasing insulin resistance and reducing β-cell function and mass. These findings emphasize the essential role of mTOR/S6K1 in orchestrating β-cell adaptation to hyperglycemia in type 2 diabetes. It is likely that treatments based on mTOR inhibition will cause exacerbation of diabetes.
Omentin-1, a Novel Adipokine, Is Decreased in Overweight Insulin-Resistant Women With Polycystic Ovary Syndrome
Authors: Tan Bee K. , Adya Raghu , Farhatullah S. , Lewandowski Kris C. , O’Hare Paul , Lehnert Hendrik , Randeva Harpal S.
Published: January 2008

OBJECTIVE—Polycystic ovary syndrome (PCOS) is associated with insulin resistance and obesity. Recent studies have shown that plasma omentin-1 levels decrease with obesity. Currently, no data exist on the relative expression and regulation of omentin-1 in adipose tissue of women with PCOS. The objective of this study was to assess mRNA and protein levels of omentin-1, including circulating omentin-1, in omental adipose tissue of women with PCOS and matched control subjects. Ex vivo and in vivo regulation of adipose tissue omentin-1 was also studied.

RESEARCH DESIGN AND METHODS—Real-time RT-PCR and Western blotting were used to assess mRNA and protein expression of omentin-1. Plasma omentin-1 was measured by enzyme-linked immunosorbent assay. The effects of d-glucose, insulin, and gonadal and adrenal steroids on adipose tissue omentin-1 were analyzed ex vivo. The in vivo effects of insulin (hyperinsulinemia) on omentin-1 levels were also assessed by a prolonged insulin-glucose infusion.

RESULTS—In addition to decreased plasma omentin-1 levels in women with PCOS (P < 0.05), compared with control subjects, there was significantly lower levels of omentin-1 mRNA (P < 0.01) and protein (P < 0.05) in omental adipose tissue of women with PCOS (P < 0.01). Furthermore, in omental adipose tissue explants, insulin and glucose significantly dose-dependently decreased omentin-1 mRNA expression, protein levels, and secretion into conditioned media (P < 0.05, P < 0.01). Also, hyperinsulinemic induction in healthy subjects significantly reduced plasma omentin-1 levels (P < 0.01).

CONCLUSIONS—Our novel findings reveal that omentin-1 is downregulated by insulin and glucose. These may, in part, explain the decreased omentin-1 levels observed in our overweight women with PCOS.
Modified Constraint-Induced Therapy in Chronic Stroke: Results of a Single-Blinded Randomized Controlled Trial
Authors: Page Stephen J , Levine Peter , Leonard Anthony , Szaflarski Jerzy P , Kissela Brett M
Published: January 2008

Background and Purpose

This single-blinded randomized controlled trial compared the efficacy of a reimbursable, outpatient, modified constraint-induced therapy (mCIT) protocol (half-hour therapy sessions occurring 3 days per week in which subjects used the more affected arm combined with less affected arm restriction 5 days per week for 5 hours; both of these regimens were administered during a 10-week period) with that of a time-matched exercise program for the more affected arm or a no-treatment control regimen.

Subjects

Thirty-five subjects with chronic stroke participated in the study.

Methods

The Action Research Arm Test (ARAT), Fugl-Meyer Assessment of Motor Recovery After Stroke (FM), and Motor Activity Log (MAL) were administered to the subjects.

Results

After intervention, significant differences were observed on the ARAT and MAL Amount of Use and Quality of Movement scales, all in favor of the mCIT group.

Discussion and Conclusion

The data affirm previous findings suggesting that this reimbursable, outpatient protocol increases more affected arm use and function. Magnitude of changes was consistent with those reported in more intense protocols, such as constraint-induced therapy.
A Cautionary Discussion about Relying on Human Capital Policy to Meet Redistributive Goals
Authors: Green David A.
Published: January 2008

Human capital policy has come to be seen as something of a panacea: acting both as a necessary input for modern growth and an effective tool for redistribution. Canada has moved strongly in the direction of linking redistribution and human capital investment. In this paper, I investigate the empirical evidence and theoretical arguments behind the claim that increasing skills investment opportunities and tying transfers to human capital investments while decreasing traditional income support will ultimately lead to a more equal, more just society. Whether this is true, of course, will depend on the notion of justice one adopts. One of my goals in this paper is to examine the implications of the kind of policy path Canada is following under different notions of fairness. I conclude that both empirical evidence and fairness considerations indicate that human capital policy does not make good redistributive policy.
Impact of Asphalt Rubber Friction Course Overlays on Tire Wear Emissions and Air Quality Models for Phoenix, Arizona, Airshed
Authors: Alexandrova Olga , Kaloush Kamil E. , Allen Jonathan O.
Published: January 2008

Tire wear contributes to atmospheric particulate matter (PM) and is regulated by the U.S. Environmental Protection Agency because PM has been shown to affect human health. Vehicle emissions are a significant source of both PM2.5 and PM10. Vehicle fleet emissions per mile traveled have been reduced significantly in the past 30 years as a result of improved engine operation and tailpipe controls. However, “zero emission” vehicles will continue to generate PM from tire wear, road wear, brake wear, and resuspended road dust. In this study, aerosol measurement techniques at Arizona State University were applied to evaluate tire wear emissions from the vehicle fleet by using the Deck Park Tunnel in Phoenix, Arizona. The Deck Park Tunnel highway surface was portland cement concrete (PCC) and was resurfaced with an asphalt rubber friction course (ARFC) layer as part of the Arizona Department of Transportation Quiet Pavements Program. This study took advantage of a rare opportunity to sample tire wear emissions at the tunnel before and after the ARFC overlay. The hypothesis was that an ARFC surface results in less tire wear than the existing PCC road surface. This paper reports on the measured PM emissions from the on-road vehicle traffic during typical highway driving conditions for the two different roadway surfaces. It presents the analysis of representative tire tread samples for tire wear marker compounds and a comparison of roughness and frictional surface characteristics as measured before and after the ARFC overlay. The study found that emission rates of tire wear per kilometer driven on PCC road surfaces were 1.4 to 2 times higher than emission rates of tire wear on ARFC road surfaces.
The Changing Landscape of Transportation Decision Making
Authors: Giuliano Genevieve
Published: January 2008

This paper examines the changes taking place in the way transportation policy and investment decisions are made. To provide an understanding of these changes, they are placed in the larger context of major trends in public-sector decision making: devolution, fragmentation, and privatization. The changes taking place in the transport sector are viewed as consistent with larger trends. The changes pose particular challenges in transportation because of its unique characteristics, and they have contributed to four problems: (a) preserving and enhancing system network benefits, (b) avoiding inefficient decisions, (c) solving transportation's externalities, and (d) ensuring accountability. The Alameda Corridor is used as an example of managing the new decision-making landscape. The paper closes with thoughts on improving the transportation decision-making process.
Taking the Leap into E-Learning
Authors: Cushnie Michele E. , Howe-Steiger Linda
Published: January 2008

In 2005, the University of California at Berkeley Institute of Transportation Studies Technology Transfer Program, with funding from the California Department of Transportation, began development of an online training program for local agencies in California. Training was developed from existing classroom courses for delivery with the web-based WebEx platform. Phase 1 (the topic of this paper) focused on delivery of synchronous (live) sessions over the Internet. Phase 2 will translate these sessions into asynchronous training available 24/7 over the web. Training topics included federal aid compliance, the Americans with Disabilities Act, traffic signal timing, and transportation planning. Lessons learned during Phase 1 include how to select software platforms, how to select appropriate course content for online delivery, how to identify and select instructors who will be able to teach online successfully, and how to work with online learners.
Reusable, Polymer‐Supported, Palladium‐Catalyzed, Atom‐ Efficient Coupling Reaction of Aryl Halides with Sodium Tetraphenylborate in Water by Focused Microwave Irradiation
Authors: Bai Lin , Wang Jin‐Xian
Published: January 2008

A rapid and efficient cross‐coupling reaction of sodium tetraphenylborate with aryl bromides was carried out in water at 120 °C in the presence of a polymer‐supported palladium catalyst and potassium carbonate under focused microwave irradiation. All four phenyl groups of sodium tetraphenylborate participated in the reaction and produced polyfunctional biaryls in excellent yields. The polymeric catalyst can be easily separated from the reaction mixture and reused more than 10 times without showing any decrease in activity.
Enantioselective Cobalt‐Catalyzed [6+2] Cycloadditions of Cycloheptatriene with Alkynes
Authors: Toselli Nicolas , Martin David , Achard Mathieu , Tenaglia Alphonse , Bürgi Thomas , Buono Gerard
Published: January 2008

The enantioselective cobalt‐catalyzed [6+2] cycloadditions of cycloheptatriene 1 with alkynes 2 is reported. Chiral phosphoramidites based on 3,3′‐disubstituted (R)‐BINOL appeared to be efficient ligands, affording the corresponding cycloadducts with good yields and up to 92 % ee. A vibrational circular dichroism study afforded the absolute configuration of new chiral (+)‐(1S,6R)‐7‐phenyl[4.2.1]bicyclo‐ nonatriene 3a and (−)‐(1S,6R)‐7‐trimethylsilyl[4.2.1]bicyclononatriene 3c.
Efficient Heterogeneous Asymmetric Catalysis of the Mukaiyama Aldol Reaction by Silica‐ and Ionic Liquid‐Supported Lewis Acid Copper(II) Complexes of Bis(oxazolines)
Authors: Doherty S. , Goodrich P. , Hardacre C. , Pârvulescu V. , Paun C.
Published: January 2008

Lewis acid complexes based on copper(II) and an imidazolium‐tagged bis(oxazoline) have been used to catalyse the asymmetric Mukaiyama aldol reaction between methyl pyruvate and 1‐methoxy‐1‐trimethylsilyloxypropene under homogeneous and heterogeneous conditions. Although the ees obtained in ionic liquid were similar to those found in dichloromethane, there was a significant rate enhancement in the ionic liquid with reactions typically reaching completion within 2 min compared with only 55 % conversion after 60 min in dichloromethane. However, this rate enhancement was offset by lower chemoselectivity in ionic liquids due to the formation of 3‐hydroxy‐1,3‐diphenylbutan‐1‐one as a by‐product. Supporting the catalyst on silica or an imidazolium‐modified silica using the ionic liquid or in an ionic liquid‐diethyl ether system completely suppressed the formation of this by‐product without reducing the enantioselectivity. Although the heterogeneous systems were characterised by a drop in catalytic activity the system could be recycled up to five times without any loss in conversion or ee.
Tandem Gold(III)‐Catalyzed Amination‐Intramolecular Hydroamination Reactions of 1‐En‐4‐yn‐3‐ols with Sulfonamides: Efficient Approach to Highly Substituted Pyrroles
Authors: Shu Xing‐Zhong , Liu Xue‐Yuan , Xiao Hui‐Quan , Ji Ke‐Gong , Guo Li‐Na , Liang Yong‐Min
Published: January 2008

A simple, convenient and efficient synthetic approach to highly substituted pyrroles has been developed by utilizing a gold(III)‐catalyzed tandem amination‐intramolecular hydroamination reaction. The first examples of gold‐catalyzed, selective amination of 1‐en‐4‐yn‐3‐ols have also been disclosed.
A Stereoselective Palladium‐Mediated Reductive Coupling of Electron‐Deficient Terminal Iodoalkenes
Authors: Batsanov Andrei S. , Knowles Jonathan P. , Samsam Benedict , Whiting Andrew
Published: January 2008

Iodoacrylate esters undergo palladium‐catalysed reductive homocoupling to derive dienyl diester derivatives. This reductive coupling can be extended to ester‐substituted terminal iododienes to derive tetraene diesters. In all cases, the reactions show relatively high levels of stereocontrol, which shows an inversion of stereochemistry about one iodoalkene unit. This process, and the suggestion that the reaction releases diiodine, is consistent with a syn‐1,2‐addition of an iodopalladium(II)‐alkene species across another iodoalkene unit (carbometallation step), followed by reductive syn‐elimination of iodopalladium iodide to derive palladium(II) iodide. It appears that under the reaction conditions employed, palladium(II) iodide may equilibrate to palladium(0) and diiodine, which can be observed or trapped out from the reaction mixture.
Dalton’s Disputed Nitric Oxide Experiments and the Origins of his Atomic Theory
Authors: Usselman Melvyn C. , Leaist Derek G. , Watson Katherine D.
Published: January 2008

In 1808 John Dalton published his first general account of chemical atomic theory, a cornerstone of modern chemistry. The theory originated in his earlier studies of the properties of atmospheric gases. In 1803 Dalton discovered that oxygen combined with either one or two volumes of nitric oxide in closed vessels over water and this pioneering observation of integral multiple proportions provided important experimental evidence for his incipient atomic ideas. Previous attempts to reproduce Dalton’s experiments have been unsuccessful and some commentators have concluded the results were fraudulent. We report a successful reconstruction of Dalton’s experiments and provide an analysis exonerating him of any scientific misconduct. But we conclude that Dalton, already thinking atomistically, adjusted experimental conditions to obtain the integral combining proportions.
Increased TGF‐Beta1 protein expression in patients with advanced colorectal cancer
Authors: Langenskiöld Marcus , Holmdahl Lena , Falk Peter , Angenete Eva , Ivarsson Marie‐Louise
Published: January 2008

Introduction

There is evidence that TGF‐β1 plays a role as a tumor suppressor in early disease and has pro‐oncogenic effects in advanced tumor stage. The aim of the study was to correlate TGF‐β1 in plasma and tissue to clinical and pathological parameters in patients with various stages of disease progression.

Methods

One hundred sixty‐nine patients who underwent surgery for a colorectal carcinoma were prospectively included. Blood samples, tumor free mucosa and tumor biopsies were assayed.

Results

TGF‐β1 protein expression in tumors increased with increasing T‐stage regardless of whether patients with metastatic disease were included or not (P = 0.0006). Patients with metastatic disease showed elevated TGF‐β1 protein expression in both tumor tissue (P = 0.004) and plasma (P = 0.001) compared to those without metastatic disease. TGF‐β1 protein expression was higher in the colon compared with the rectum in both tumor tissue and tumor‐free bowel (P = 0.03), regardless of whether patients with metastatic disease were included or not. This difference was mainly attributable to a higher TGF‐β1 protein expression in non‐metastatic patients with lymph node positivity (P = 0.005).

Conclusions

Higher TGF‐β1 protein expression is associated with increasing T‐stage and metastatic disease, indicating that TGF‐β1 is of importance in tumor progression. The localization of the tumor seems to influence the TGF‐β1 protein expression in patients with tumor cell‐positive lymph nodes. J. Surg. Oncol. 2008;97:409–415. © 2008 Wiley‐Liss, Inc.
Loss of trimethylation at lysine 27 of histone H3 is a predictor of poor outcome in breast, ovarian, and pancreatic cancers
Authors: Wei Yongkun , Xia Weiya , Zhang Zhihong , Liu Jinsong , Wang Huamin , Adsay Nazmi V. , Albarracin Constance , Yu Dihua , Abbruzzese James L. , Mills Gordon B. , Bast Robert C. , Hortobagyi Gabriel N. , Hung Mien‐Chie
Published: January 2008

Methylation of lysine 27 on histone H3 (H3K27) by the EZH2 complex is an epigenetic mark that mediates gene silencing. EZH2 is overexpressed in many cancers and correlates with poor prognosis in both breast and prostate cancers. However, the status of H3K27 methylation and its clinical implication in cancer patients have not been reported. We thus examined trimethylation of H3K27 (H3K27me3) by immunohistochemistry and its association with clinical variables and prognosis in breast, ovarian, and pancreatic cancers. We found that H3K27me3 expression was significantly lower in breast, ovarian and pancreatic cancers than in normal tissues (62% in breast cancer vs. 88% in normal breast tissue, P = 0.001; 38.4% in ovarian cancer vs. 83.3% in normal ovarian tissue, P < 0.05; and 26% in pancreatic cancer vs. 89% in normal pancreatic tissue, P < 0.001). H3K27me3 expression showed significant prognostic impact in breast, ovarian and pancreatic cancers in univariate survival analyses. In all three cancer types, patients with low expression of H3K27me3 had significantly shorter overall survival time when compared with those with high H3K27me3 expression. In a multivariate model, H3K27me3 expression was an independent prognostic value for overall survival in all three cancer types. These results suggest that H3K27me3 expression is a prognostic indicator for clinical outcome in patients with breast, ovarian, and pancreatic cancers. © 2008 Wiley‐Liss, Inc.
Biocatalytic hydrogels by template polymerization
Authors: El‐Sherif H. , El‐Masry M.
Published: January 2008

Novel ionizable hydrogels were prepared from poly(acrylic acid) and dimethylaminoethyl methacrylate monomer employing template polymerization technique as an alternative to traditional physical and chemical crosslinking. The mode of interaction, as proved by Fourier Transform Infrared Spectroscopy (FTIR), was multiple H‐bonding between the tertiary amino group of the monomer and the carboxylic groups of the polymer. The hydrogels represented suitable matrices for enzyme immobilization. The effect of varying the polymer–monomer molar ratio on the swelling kinetics and parameters was investigated. The dynamic swelling isotherm exhibited a Fickian mode of penetrant sorption and a plateau that increases with the amino group content. A polymer complex of molar ratio (polymer:monomer) 0.5:0.8 had a weight swelling ratio of 10 and 7 at pHs 3 and 8, respectively. The proven pH sensitivity together with the amphoteric character of these hydrogels make them good candidates for another bioapplication such as oral delivery systems of therapeutic peptides and proteins. The structural integrity of the hydrogels was proved by their swelling reversibility. β‐Galactosidase, as an acidic model enzyme, was immobilized covalently on the synthesized hydrogels. The maximum enzyme velocity (Vmax) was enhanced to 19 µmol/min/mg, for polycomplex of molar ratio 0.5:0.8, compared with 3.2 µmol/min/mg for the free enzyme. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of take‐up speed on the structure and properties of melt‐spun poly(L‐lactic acid) fibers
Authors: Kim Min Sup , Kim Jeong Cheol , Kim Young Ho
Published: January 2008

Poly(L‐lactic acid) (PLLA) filament fibers were prepared by one‐step melt spinning process and the effects of variations in take‐up speed on their thermal properties, mechanical properties, and crystalline structures were investigated. Differential scanning calorimetry (DSC) results revealed that the PLLA fibers showed multiple melting peaks and that the melting peak appearing at a lower temperature moved lower while that at a higher temperature moved higher with increasing take‐up speed. The glass transition temperature (Tg) obtained from dynamic mechanical analysis (DMA) increased with increasing take‐up speed. The tenacity increased and the boiling water shrinkage (BWS) decreased with increasing take‐up speed. However, these mechanical and thermal properties were stabilized at take‐up speeds over 3500 m/min. The melt‐spun PLLA fibers of this study showed an α‐form crystal structure which was not affected by the take‐up speed. The change in the tendency of the thermal and mechanical properties at around 3500 m/min did not appear to result from the change in crystal form but rather from the change in crystallite size and crystallite orientation. Copyright © 2008 John Wiley & Sons, Ltd.
Adsorption of carbaryl using molecularly imprinted microspheres prepared by precipitation polymerization
Authors: Yao Wei , Fang Yanjun , Gao Guoliang Li, Zhixian , Cheng Yiyong
Published: January 2008

To obtain the desired specific adsorbents for carbaryl to enrichment, separation, and analysis of trace pesticide residues in environmental water, molecularly imprinted polymer (MIP) microspheres were prepared by precipitation polymerization using carbaryl, methacrylic acid (MAA), ethylene glycol dimethacrylate (EGDMA), azobisisobutyronitrile (AIBN), and acetonitrile as template, functional monomer, cross‐linker, initiator, and porogen, respectively. Molecular modeling software was used to compute rational interaction between the template molecule and function monomer. The adsorption properties of carbaryl in acetonitrile for imprinted microspheres were evaluated by equilibrium rebinding experiments. Scatchard plot analysis revealed that there was one class of binding sites populated in the imprinted polymer microspheres with dissociation constants of 3.3 × 10−2 mol/l and an apparent maximum number of 1.95 µmol/g. The specificity of the imprinted microspheres was investigated by binding analysis using carbaryl and structurally related carbamate pesticides. The results indicated that the obtained imprinted microspheres showed a good selectivity for carbaryl. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluation of reproducibility of protein identification results after multidimensional human serum protein separation
Authors: Stalder Daniel , Haeberli André , Heller Manfred
Published: January 2008

We developed a gel‐ and label‐free proteomics platform for comparative studies of human serum. The method involves the depletion of the six most abundant proteins, protein fractionation by Off‐Gel™ IEF and RP‐HPLC, followed by tryptic digestion, LC‐MS/MS, protein identification, and relative quantification using probabilistic peptide match score summation (PMSS). We evaluated performance and reproducibility of the complete platform and the individual dimensions, by using chromatograms of the RP‐HPLC runs, PMSS based abundance scores and abundance distributions as objective endpoints. We were interested if a relationship exists between the quantity ratio and the PMSS score ratio. The complete analysis was performed four times with two sets of serum samples containing different concentrations of spiked bovine beta‐lactoglobulin (0.1 and 0.3%, w/w). The two concentrations resulted in significantly differing PMSS scores when compared to the variability in PMSS scores of all other protein identifications. We identified 196 proteins, of which 116 were identified four times in corresponding fractions whereof 73 qualified for relative quantification. Finally, we characterized the PMSS based protein abundance distributions with respect to the two dimensions of fractionation and discussed some interesting patterns representing discrete isoforms. We conclude that combination of Off‐Gel™ electrophoresis (OGE) and HPLC is a reproducible protein fractionation technique, that PMSS is applicable for relative quantification, that the number of quantifiable proteins is always smaller than the number of identified proteins and that reproducibility of protein identifications should supplement probabilistic acceptance criteria.
Damage formation in Ge during Ar+ implantation at 15 K
Authors: Hayes M. , Schroeter A. , Wendler E. , Wesch W. , Auret F. D. , Nel J. M.
Published: January 2008

Ar+ ions were implanted into Ge samples with (100), (110), (111) and (112) orientations at 15 K with fluences ranging from 1 × 1011 to 1 × 1014 cm−2. The Rutherford backscattering (RBS) technique in the channelling orientation was used to study the damage build‐up in situ. Implantation and RBS measurements were performed without changing the target temperature. The samples were mounted on a four axis goniometer cooled by a close cycle He cryostat. The implantations were performed with the surface being tilted 7° off the ion beam direction to prevent channelling effects. After each 300 keV Ar+ implantation, RBS analysis performed with 1.4 MeV He+ ions. The damage efficiency per ion was found to be Pa =4.5 × 10−14 cm−2. There is no significant difference in the values found for the four different orientations. This, together with the high value (5 times higher than that found in Si), gives rise to the assumption of amorphous pocket formation per incident ion, i.e. direct impact amorphisation, already at low implantation fluences. At higher fluences, when collision cascades overlap, there is a growth of the already amorphised regions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterisation of InAs‐based epilayers by FTIR spectroscopy
Authors: Baisitse T. R. , Forbes A. , Katumba G. , Botha J. R. , Engelbrecht J. A. A.
Published: January 2008

In this paper, infrared reflectance spectroscopy was employed to extract information on the optical and electrical properties of metal organic vapour phase epitaxial (MOVPE) grown InAs and InAsSb epilayers. These epitaxial layers were grown on InAs and GaAs substrates and characterised by infrared reflectance spectroscopy and Hall measurements. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron field emission from nanostructured surfaces of GaN and AlGaN
Authors: Evtukh A. , Yilmazoglu O. , Litovchenko V. , Semenenko M. , Gorbanyuk T. , Grygoriev A. , Hartnagel H. , Pavlidis D.
Published: January 2008

The possibility of high frequency electromagnetic wave generation by field emission based devices has great interest. The wide bandgap materials GaN and AlGaN are very promising for these applications due to low electron affinity and the existence of satellite valleys in conduction band. The results of investigations of the peculiarities of electron field emission from nanostructured surfaces of GaN and AlGaN are presented. Multilayer GaN and AlGaN structures with various levels of layer doping on sapphire and bulk GaN substrates were used as initial wafers. The surface of the upper layers was nanostructured by photoelectrochemical etching in water solution of KOH. Intensive electron field emission into vacuum was observed and explained by low electron affinity and electric field enhancement on surface nanowires. A decrease of the slope in the Fowler‐Nordheim characteristics was revealed. The changing slope suggests a lowering of effective work function. It is caused by electron heating and transfer into an upper satellite valley with lower electron affinity. A theory was developed for the observed phenomena and interpretation of results. It is baseed on electron intervalley transition upon heating and on energy band reconstruction of the surface of the nanowires due to quantum size‐confinement effect. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of growth conditions on grown‐in defect formation and luminescence efficiency in Ga(In)NP epilayers grown by molecular‐beam epitaxy
Authors: Dagnelund D. , Buyanova I. A. , Chen W. M. , Utsumi A. , Furukawa Y. , Wakahara A. , Yonezu H.
Published: January 2008

A detailed study of the impact of different growth conditions (i.e. ion bombardment, nitrogen flow and In content) on the defect formation in Ga(In)NP epilayers grown on GaP substrates by solid‐source molecular beam epitaxy is performed. Reduced nitrogen ion bombardment during the growth is shown to significantly reduce formation of defects acting as competing recombination centers, such as a Ga interstitial defect and other unidentified defects revealed by optically detected magnetic resonance. Further, high nitrogen flow is found to be even more effective than the ion bombardment in introducing the defects. The incorporation of In by 5.1% is, on the other hand, found not to affect the introduction of defects. The results provide a useful insight into the formation mechanism of the defects that will hopefully shed light on a control of the defect introduction in the alloys by optimizing growth conditions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Band gap energy fluctuations in InGaN films grown by RF‐MBE with changing nitrogen supply rate investigated by a piezoelectric photothermal spectroscopy
Authors: Komaki H. , Shimohara T. , Sakai K. , Katayama R. , Onabe K. , Fukuyama A. , Ikari T.
Published: January 2008

In this study, non‐radiative recombination center in InGaN films with varying III/N ratio grown by rf‐molecular beam epitaxy was investigated directly by piezoelectric photothermal spectroscopy (PPTS). To clarify the influence of the III/N supply ratio during the InGaN layer growth, the nitrogen flow rate was changed from 1.0 to 2.0 sccm. Since metallic‐indium droplets and phase separation were observed for the samples grown by low nitrogen flow rate, it was found that these have been grown under a group‐III‐rich condition. With increasing nitrogen flow rate, the indium content in InGaN films increased. The estimated non‐radiative recombination edges determined from PPTS method (PPT edge) red‐shifted with increasing the nitrogen flow rate. The energy difference between estimated band edge and the PPT edges increased with increasing flow rate under group‐III rich condition, and became saturated under the N‐rich condition. It is considered that the existence of the phase separation is related to this behavior. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hopping currents in the intrinsic region of III‐N‐V quantum well structures in the tight binding approximation
Authors: Varonides Argyrios C. , Spalletta Robert A.
Published: January 2008

We calculate for the first time Nearest Neighbor Hopping (NNH) current densities for III‐N‐V heterostructures embedded in the intrinsic layer of p‐i‐n geometries. We start from a general formalism that relates the density of states in individual wells with the transition probabilities from a quantum well state to a neighboring one, in a superlattice‐geometry. In the process, we find and point out the fact that there is zero hopping‐current without Fermi level splitting for any two consecutive layers.). We then relate the eigen‐energies with the transition probabilities and conclude that NNH ‐currents are of the order of 0.06 mA/cm2 at the most and in room temperatures, and depend on (a) device geometry (b) temperature (c) conduction band discontinuity and (d) Fermi level splitting. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Calculation of the angular distribution of the surface excitation parameter for Ti, Fe, Cu, Pd, Ag, and Au
Authors: Pauly N. , Tougaard S.
Published: January 2008

We define surface excitation parameter (SEP) as the change in excitation probability of an electron caused by the presence of the surface in comparison with an infinite medium, and we calculate the angular dependence of the SEP for different metals (Ti, Fe, Cu, Pd, Ag, and Au), for angles to the surface normal between 10° and 70° and for different energies. The calculations are based on a study of energy‐differential inelastic electron scattering cross‐sections obtained from the software Quantitative analysis of Electron Energy Losses at Surfaces (QUEELS) valid for reflection‐electron‐energy‐loss spectroscopy (REELS). The intensity of the surface excitation is isolated from the total spectrum by subtracting the volume component for an infinite medium and the SEP is deduced from it. Copyright © 2008 John Wiley & Sons, Ltd.
Quantification issues of trace metals analysis on silicon oxide and nitride films by using VPD‐ICP‐MS and VPD‐GF‐AAS
Authors: Yeh Ming‐Peng , Hsien Casey , Huang Cheng‐Sung , Lin Ter‐Chuan
Published: January 2008

Vapor phase decomposition (VPD) is a pretreatment technique for collecting trace metal contaminants on the surface of a Si wafer. Such trace metals can be identified and quantified by inductively coupled plasma mass spectrometry (ICP‐MS) or graphite furnace atomic absorption spectroscopy (GF‐AAS). However, the analytical results can be influenced by the Si‐matrix in the VPD samples. This article discusses the approaches to eliminate the interference caused by Si‐matrix. When the thickness of oxide film on wafer surface is less than 100 Å, the quantification results of ICP‐MS analysis will not be affected by Si‐matrix in the VPD samples. Except this, the Si‐matrix must be removed before analysis. An improved heating pretreatment approach has been adopted successfully to eliminate the Si‐matrix. For GF‐AAS analysis, the Si‐matrix will influence the sodium and aluminum analyses. Adding HNO3 to the graphite furnace tubing after sample injection could also eliminate the interference caused by the Si‐matrix. The method detection limits (MDLs) of VPD‐GF‐AAS and VPD‐ICP‐MS range from 0.04 to 0.55 × 1010 atoms cm−2 and 0.05 to 1.73 × 109 atoms cm−2, respectively. Copyright © 2008 John Wiley & Sons, Ltd.
Use of Iodine as a Tool to Understand Wheat Starch Pasting Properties
Authors: Saibene Debora , Seetharaman Koushik
Published: January 2008

The ability of iodine to bind amylose has been used to understand a variety of structural and functional aspects of starch in food systems. In this study, the changes in starch granule swelling, polymer leaching and their relationship to pasting properties was investigated by adding iodine to the starch slurry at either room temperature or 95°C. The objective of the study was to investigate the contribution of leached and solubilized starch polymers on the pasting behavior of wheat starch. The addition of very small amounts of iodine (0.1%, dry basis, db) at room temperature increased peak and final pasting viscosities as compared to when no iodine was added. Further increases in iodine concentration resulted in a decrease in peak and final pasting viscosities. The amount of iodine required to completely inhibit granule swelling was more than that required to minimize amylose leaching from the granule. Adding increasing amounts of iodine at 95°C to the starch slurry resulted in the gradual decrease in peak and final pasting viscosities. The contrasting effects of iodine on paste viscosity behavior when added at room temperature or at 95°C suggest that the contribution of extra‐granular amylose on the setback viscosity is minimal and a larger proportion of amylose is retained in the intragranular spaces.