bluuebunny/crossref_metadata_2025 huggingface dataset:
Who is Your Preferred Neighbor? Partisan Residential Preferences and Neighborhood Satisfaction
Authors: Hui Iris
Published: April 2013

Do people specifically seek to live among political co-partisans when they relocate? Does the partisan composition of the neighborhood affect their level of residential satisfaction? Drawing on survey data and a survey-embedded experiment, I find that people have a clear preference for co-partisans. Both Republican and Democrat identifiers prefer more co-partisans in their neighborhood. Although the preference is not the primary factor in deciding where to settle, the partisan composition of a neighborhood does affect an individual’s sense of neighborhood satisfaction. Results from a survey-embedded experiment show that respondents’ subjective satisfaction is sensitive to objective facts about their neighborhood. Respondents’ satisfaction slightly decreases when told their neighborhood has a higher presence of members of the opposite party than perceived.
Motivational Interviewing in the Health Care Setting
Authors: Johnston Craig A. , Stevens Brian E.
Published: April 2013

Alcohol use disorders are related to many negative health, emotional, societal, and economic consequences. These disorders are often difficult to treat because individuals suffering from them tend to be ambivalent about and resistant to change. Motivational interviewing provides health care providers with the appropriate tools to treat individuals who are resistant to change and can help with long-term lifestyle and behavioral changes. Motivational interviewing has also been shown to be helpful when a lifestyle approach to treatment is used.
Sync and Swim
Authors: Ross Alexander , Jami Humaira , Young Heather A. , Katz Richard
Published: April 2013

Background: Medication nonadherence is associated with higher cost of care and poor outcomes. Medication refill consolidation (synchronization of refill dates for patients on multiple drugs) is an important component of regimen complexity. We presumed that Medicaid patients with a 30-day medication supply limit would have significant difficulty with refill consolidation. We evaluated regimen complexity and refill consolidation in relation to medication adherence in the Medicaid population. Methods: A survey was administered to 50 Medicaid patients taking 2 or more daily medications in the outpatient setting. The survey included demographics, 13 items related to medication and pharmacy history, and 10 items related to medication regimen complexity and refill consolidation. Chi-square analysis was used to assess the relationship between adherence and missed medication doses due to regimen complexity. Wilcoxon rank sum test was used to determine association between total number of prescribing providers and number of daily medications with various aspects of regimen complexity. Results: 52% were required to go to the pharmacy more than once per month to keep all of their medications filled and 46% missed a day or more of medication because their medications must be refilled on different dates. Those who missed a day or more of medication because of need to refill prescriptions on different days had higher number of prescriptions ( P = .03) and higher number of prescribers ( P = .03). Conclusion: Medicaid patients had low medication adherence in the context of high regimen complexity and poor refill consolidation. This population would benefit from interventions focused on improving synchronization of medication refills.
Enlarging a training set for genomic selection by imputation of un-genotyped animals in populations of varying genetic architecture
Authors: Pimentel Eduardo CG , Wensch-Dorendorf Monika , König Sven , Swalve Hermann H
Published: April 2013

Background

The most common application of imputation is to infer genotypes of a high-density panel of markers on animals that are genotyped for a low-density panel. However, the increase in accuracy of genomic predictions resulting from an increase in the number of markers tends to reach a plateau beyond a certain density. Another application of imputation is to increase the size of the training set with un-genotyped animals. This strategy can be particularly successful when a set of closely related individuals are genotyped.

Methods

Imputation on completely un-genotyped dams was performed using known genotypes from the sire of each dam, one offspring and the offspring’s sire. Two methods were applied based on either allele or haplotype frequencies to infer genotypes at ambiguous loci. Results of these methods and of two available software packages were compared. Quality of imputation under different population structures was assessed. The impact of using imputed dams to enlarge training sets on the accuracy of genomic predictions was evaluated for different populations, heritabilities and sizes of training sets.

Results

Imputation accuracy ranged from 0.52 to 0.93 depending on the population structure and the method used. The method that used allele frequencies performed better than the method based on haplotype frequencies. Accuracy of imputation was higher for populations with higher levels of linkage disequilibrium and with larger proportions of markers with more extreme allele frequencies. Inclusion of imputed dams in the training set increased the accuracy of genomic predictions. Gains in accuracy ranged from close to zero to 37.14%, depending on the simulated scenario. Generally, the larger the accuracy already obtained with the genotyped training set, the lower the increase in accuracy achieved by adding imputed dams.

Conclusions

Whenever a reference population resembling the family configuration considered here is available, imputation can be used to achieve an extra increase in accuracy of genomic predictions by enlarging the training set with completely un-genotyped dams. This strategy was shown to be particularly useful for populations with lower levels of linkage disequilibrium, for genomic selection on traits with low heritability, and for species or breeds for which the size of the reference population is limited.
Different healing process of esophageal large mucosal defects by endoscopic mucosal dissection between with and without steroid injection in an animal model
Authors: Nonaka Kouichi , Miyazawa Mitsuo , Ban Shinichi , Aikawa Masayasu , Akimoto Naoe , Koyama Isamu , Kita Hiroto
Published: April 2013

Background

Stricture formation is one of the major complications after endoscopic removal of large superficial squamous cell neoplasms of the esophagus, and local steroid injections have been adopted to prevent it. However, fundamental pathological alterations related to them have not been well analyzed so far. The aim of this study was to analyze the time course of the healing process of esophageal large mucosal defects resulting in stricture formation and its modification by local steroid injection, using an animal model.

Methods

Esophageal circumferential mucosal defects were created by endoscopic mucosal dissection (ESD) for four pigs. One pig was sacrificed five minutes after the ESD, and other two pigs were followed-up on endoscopy and sacrificed at the time of one week and three weeks after the ESD, respectively. The remaining one pig was followed-up on endoscopy with five times of local steroid injection and sacrificed at the time of eight weeks after the ESD. The esophageal tissues of all pigs were subjected to pathological analyses.

Results

For the pigs without steroid injection, the esophageal stricture was completed around three weeks after the ESD on both endoscopy and esophagography. Histopathological examination of the esophageal tissues revealed that spindle-shaped α-smooth muscle actin (SMA)-positive myofibroblasts arranged in a parallel fashion and extending horizontally were identified at the ulcer bed one week after the ESD, and increased contributing to formation of the stenotic luminal ridge covered with the regenerated epithelium three weeks after the ESD. The proper muscle layer of the stricture site was thinned with some myocytes which seemingly showed transition to the myofibroblast layer. By contrast, for the pig with steroid injection, esophageal stricture formation was not evident with limited appearance of the spindle-shaped myofibroblasts, instead, appearance of stellate or polygocal SMA-positive stromal cells arranged haphazardly in the persistent granulation tissue of the ulcer site.

Conclusions

Proliferation of spindle-shaped myofibroblasts arranged in a parallel fashion is likely to play an important role in stricture formation after circumferential mucosal defects by esophageal ESD, which may be related to the thinning of the proper muscle layer in the healing course of the defects. Local steroid injection seems to be effective to prevent the stricture through the modification of this process.
Analysis of EIF4G1 in ethnic Chinese
Authors: Li Kai , Tang Bei-sha , Guo Ji-feng , Lou Ming-xing , Lv Zhan-yun , Liu Zhen-hua , Tian Yun , Song Cheng-yuan , Xia Kun , Yan Xin-xiang
Published: April 2013

Background

Eukaryotic translation initiation factor 4-gamma 1 (EIF4G1) gene mutations have recently been reported in autosomal dominant, late-onset Parkinson’s disease (LOPD). We carried out genetic analysis to determine the prevalence of EIF4G1 variants in an ethnic Chinese population and to better understand the association between EIF4G1 and PD.

Methods

We conducted a comprehensive genetic analysis of EIF4G1 in a cohort of 29 probands of autosomal dominant, LOPD families. Polymerase chain reaction (PCR) analysis and sequencing was carried out of the entire EIF4G1 exonic regions and exon-intron boundaries. Specific mutation and exonic variants were chosen for further sequencing in a case–control study including 503 sporadic PD and 508 healthy controls. Statistical significance was analyzed by the Chi-square test.

Results

Our analysis revealed three exonic variants (rs2230571, rs13319149 and rs2178403) and eight intronic variants across the entire EIF4G1 gene. No reported mutations were detected in EIF4G1 exonic regions. The synonymous coding variant rs2230571 in exon 27 and the eight intronic variants were not used for further sequencing, but the specific mutation c.3614G > A (p.R1205H) and the two nonsynonymous variants (rs13319149 and rs2178403) were chosen for further analysis in a case–control study. None of the 503 sporadic PD or 508 healthy controls carried p.R1205H, and there was no statistical significance in rs2178403 genotype or allele frequencies in EIF4G1 between the PD cases and the healthy controls (p = 0.184 and p = 0.774, respectively; Chi-square test). The rs13319149 genotype in all PD cases and healthy controls was GG.

Conclusions

Our data indicate that in an ethnic Chinese population, the pathogenic mutation p.R1205H in EIF4G1 is not common and that EIF4G1 exonic variants rs2178403 and rs13319149 are not associated with PD. EIF4G1 does not appear to be a frequent cause of PD in this ethnic Chinese population.
A pilot study: sequential gemcitabine/cisplatin and icotinib as induction therapy for stage IIB to IIIA non-small-cell lung adenocarcinoma
Authors: Lv Chao , Ma Yuanyuan , Feng Qin , Fang Fang , Bai Hua , Zhao Bingtian , Yan Shi , Wu Nan , Zheng Qingfeng , Li Shaolei , Chen Jinfeng , Wang Jia , Feng Yuan , Wang Yuzhao , Pei Yuquan , Fang Jian , Yang Yue
Published: April 2013

Background

A phase II clinical trial previously evaluated the sequential administration of erlotinib after chemotherapy for advanced non-small-cell lung cancer (NSCLC). This current pilot study assessed the feasibility of sequential induction therapy in patients with stage IIB to IIIA NSCLC adenocarcinoma.

Methods

Patients received gemcitabine 1,250 mg/m2 on days 1 and 8 and cisplatin 75 mg/m2 on day 1, followed by oral icotinib (125 mg, three times a day) on days 15 to 28. A repeatcomputed tomography(CT) scan evaluated the response to the induction treatment after two 4-week cycles and eligible patients underwent surgical resection. The primary objective was to assess the objective response rate (ORR), while EGFR and KRAS mutations and mRNA and protein expression levels of ERCC1 and RRM1 were analyzed in tumor tissues and blood samples.

Results

Eleven patients, most with stage IIIA disease, completed preoperative treatment. Five patients achieved partial response according to the Response Evaluation Criteria in Solid Tumors (RECIST) criteria (ORR=45%) and six patients underwent resection. Common toxicities included neutropenia, alanine transaminase (ALT) elevation, fatigue, dry skin, rash, nausea, alopecia and anorexia. No serious complications were recorded perioperatively. Three patients had exon 19 deletions and those with EGFR mutations were more likely to achieve a clinical response (P= 0.083). Furthermore, most cases who achieved a clinical response had low levels of ERCC1 expression and high levels of RRM1.

Conclusions

Two cycles of sequentially administered gemcitabine/cisplatin with icotinib as an induction treatment is a feasible and efficacious approach for stage IIB to IIIA NSCLC adenocarcinoma, which provides evidence for the further investigation of these chemotherapeutic and molecularly targeted therapies.
Improved seam carving for stereo image resizing
Authors: Yue Bin , Hou Chun-ping , Zhou Yuan
Published: April 2013

When stereo images are shown in three-dimensional (3D) display devices of different aspect ratios, the resizing algorithm for single image could lead to shape and depth distortion of the stereo image’s main content. This paper aims to propose a novel method for retargeting stereo image pairs without distorting important objects in the scene while still maintaining the consistency between the left and right images. We extended seam carving algorithm to stereo images. The novelty of our method is that important objects are determined by jointly considering the intensities of gradients and visual fusion area. The retargeted stereo pair has a feasible 3D interpretation that is similar to the original one. Our method protected the important content and reduced the visual distortion in each of the images as well as the depth distortion. Experimental results are presented to demonstrate that the proposed method effectively guaranteed the geometric consistency of resized stereo images.
Existence of solutions and nonnegative solutions for a class of "Equation missing" -Laplacian differential systems with multipoint and integral boundary value conditions
Authors: Zhi Guizhen , Guo Yunrui , Wang Yan , Zhang Qihu
Published: April 2013

This paper explores the existence of solutions for a class of

p
(
t
)

-Laplacian differential systems with multipoint and integral boundary value conditions via Leray-Schauder’s degree. Moreover, the existence of nonnegative solutions is discussed.

MSC:34B10.
Fast CAVLD of H.264/AVC on bitstream decoding processor
Authors: Seo Jung-Han , Jo Hyun-Ho , Sim Dong-Gyu , Kim Doo-Hyun , Song Joon-Ho
Published: April 2013

This paper presents a fast context-based adaptive variable-length decoding (CAVLD) method of H.264/AVC with a very long instruction word-based bitstream processing unit (BsPU) designed for entropy decoding of multiple video formats. A new table mapping algorithm for the coeff_token, level, and run_before syntax elements of the quantized transform coefficients is proposed, and many branch operations are removed by utilizing several designated instructions in the BsPU. By applying designated instructions and the proposed table mapping algorithm to CAVLD, we found that the proposed fast CAVLD method achieves an increase of approximately 47% in the decoding speed and a reduction of approximately 59% in memory requirements for the table mapping.
Secure relay selection based on learning with negative externality in wireless networks
Authors: Zhao Caidan , Xiao Liang , Kang Shan , Chen Guiquan , Li Yunzhou , Huang Lianfen
Published: April 2013

In this paper, we formulate relay selection into a Chinese restaurant game. A secure relay selection strategy is proposed for a wireless network, where multiple source nodes send messages to their destination nodes via several relay nodes, which have different processing and transmission capabilities as well as security properties. The relay selection utilizes a learning-based algorithm for the source nodes to reach their best responses in the Chinese restaurant game. In particular, the relay selection takes into account the negative externality of relay sharing among the source nodes, which learn the capabilities and security properties of relay nodes according to the current signals and the signal history. Simulation results show that this strategy improves the user utility and the overall security performance in wireless networks. In addition, the relay strategy is robust against the signal errors and deviations of some user from the desired actions.
Group I p21-activated kinases facilitate Tax-mediated transcriptional activation of the human T-cell leukemia virus type 1 long terminal repeats
Authors: Chan Ching-Ping , Siu Yeung-Tung , Kok Kin-Hang , Ching Yick-Pang , Tang Hei-Man Vincent , Jin Dong-Yan
Published: April 2013

Background

Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia and tropical spastic paraparesis. HTLV-1 encodes transactivator protein Tax that interacts with various cellular factors to modulate transcription and other biological functions. Additional cellular mediators of Tax-mediated transcriptional activation of HTLV-1 long terminal repeats (LTR) remain to be identified and characterized.

Results

In this study, we investigated the regulatory role of group I p21-activated kinases (Paks) in Tax-induced LTR activation. Both wild-type and kinase-dead mutants of Pak3 were capable of potentiating the activity of Tax to activate LTR transcription. The effect of Paks on the LTR was attributed to the N-terminal regulatory domain and required the action of CREB, CREB-regulating transcriptional coactivators (CRTCs) and p300/CREB-binding protein. Paks physically associated with Tax and CRTCs. Paks were recruited to the LTR in the presence of Tax. siRNAs against either Pak1 or Pak3 prevented the interaction of Tax with CRTC1 and the recruitment of Tax to the LTR. These siRNAs also inhibited LTR-dependent transcription in HTLV-1-transformed MT4 cells and in cells transfected with an infectious clone of HTLV-1.

Conclusion

Group I Paks augment Tax-mediated transcriptional activation of HTLV-1 LTR in a kinase-independent manner.
Intellectual disability associated with a homozygous missense mutation in THOC6
Authors: Beaulieu Chandree L , Huang Lijia , Innes A Micheil , Akimenko Marie-Andree , Puffenberger Erik G , Schwartz Charles , Jerry Paul , Ober Carole , Hegele Robert A , McLeod D Ross , Schwartzentruber Jeremy ,   FORGE Canada Consortium, Majewski Jacek , Bulman Dennis E , Parboosingh Jillian S , Boycott Kym M
Published: April 2013

Background

We recently described a novel autosomal recessive neurodevelopmental disorder with intellectual disability in four patients from two related Hutterite families. Identity-by-descent mapping localized the gene to a 5.1 Mb region at chromosome 16p13.3 containing more than 170 known or predicted genes. The objective of this study was to identify the causative gene for this rare disorder.

Methods and results

Candidate gene sequencing followed by exome sequencing identified a homozygous missense mutation p.Gly46Arg, inTHOC6. No other potentially causative coding variants were present within the critical region on chromosome 16. THOC6 is a member of the THO/TREX complex which is involved in coordinating mRNA processing with mRNA export from the nucleus.In situhybridization showed thatthoc6is highly expressed in the midbrain and eyes. Cellular localization studies demonstrated that wild-type THOC6 is present within the nucleus as is the case for other THO complex proteins. However, mutant THOC6 was predominantly localized to the cytoplasm, suggesting that the mutant protein is unable to carry out its normal function. siRNA knockdown ofTHOC6revealed increased apoptosis in cultured cells.

Conclusion

Our findings associate a missense mutation inTHOC6with intellectual disability, suggesting the THO/TREX complex plays an important role in neurodevelopment.
Characterization of the biology and infectivity of Leishmania infantum viscerotropic and dermotropic strains isolated from HIV+ and HIV- patients in the murine model of visceral leishmaniasis
Authors: Cunha Joana , Carrillo Eugenia , Sánchez Carmen , Cruz Israel , Moreno Javier , Cordeiro-da-Silva Anabela
Published: April 2013

Background

Leishmaniasis is a group of diseases with a variety of clinical manifestations. The form of the disease is highly dependent on the infectiveLeishmaniaspecies and the immunological status of the host. The infectivity of the parasite strain also plays an important role in the progression of the infection. The aim of this work is to understand the influence of the natural infectivity ofLeishmaniastrains in the outcome of visceral leishmaniasis.

Methods

In this study we have characterized four strains ofL. infantumin terms of molecular typing,in vitrocultivation and differentiation. Two strains were isolated from HIV+ patients with visceral leishmaniasis (Bibiano and E390M), one strain was isolated from a cutaneous lesion in an immunocompetent patient (HL) and another internal reference strain causative of visceral leishmaniasis (ST) also from an immunocompetent patient was used for comparison. For this objective, we have compared their virulence byin vitroandin vivoinfectivity in a murine model of visceral leishmaniasis.

Results

Molecular typing unraveled a newk26sequence attributed to MON-284 zymodeme and allowed the generation of a molecular signature for the identification of each strain.In vitrocultivation enabled the production of promastigotes with comparable growth curves and metacyclogenesis development. The HL strain was the most infective, showing the highest parasite loadsin vitrothat were corroborated with thein vivoassays, 6 weeks post-infection in BALB/c mice. The two strains isolated from HIV+ patients, both belonging to two different zymodemes, revealed different kinetics of infection.

Conclusion

Differences ininvitro andin vivoinfectivity found in the murine model were then attributed to intrinsic characteristics of each strain. This work is supported by other studies that present the parasite’s inherent features as factors for the multiplicity of clinical manifestations and severity of leishmaniasis.
Ammonia-oxidizing archaea and bacteria are structured by geography in biological soil crusts across North American arid lands
Authors: Marusenko Yevgeniy , Bates Scott T , Anderson Ian , Johnson Shannon L , Soule Tanya , Garcia-Pichel Ferran
Published: April 2013

Introduction

Biological soil crusts (BSCs) can dominate surface cover in dry lands worldwide, playing an integral role in arid land biogeochemistry, particularly in N fertilization through fixation and cycling. Nitrification is a characteristic and universal N transformation in BSCs that becomes important for the export of N beyond the microscopic bounds of the crust itself. The contribution of ammonia-oxidizing bacteria (AOB) in BSCs has been shown, but the role and extent of the recently discovered ammonia-oxidizing archaea (AOA) have not.

Methods

We sampled various types of crusts in four desert regions across the western United States and characterized the composition and size of ammonia-oxidizing communities using clone libraries and quantitative PCR targeting the amoA gene, which codes for the ammonia monooxygenase enzyme, universally present in ammonia-oxidizing microbes.

Results

All archaeal amoA sequences retrieved from BSCs belonged to the Thaumarchaeota (Nitrososphaera associated Group I.1b). Sequences from the Sonoran Desert, Colorado Plateau, and Great Basin were indistinguishable from each other but distinct from those of the Chihuahuan Desert. Based on amoA gene abundances, archaeal and bacterial ammonia oxidizers were ubiquitous in our survey, but the ratios of archaeal to bacterial ammonia oxidizers shifted from bacterially dominated in northern, cooler deserts to archaeally dominated in southern, warmer deserts.

Conclusions

Archaea are shown to be potentially important biogeochemical agents of biological soil crust N cycling. Conditions associated with different types of BSCs and biogeographical factors reveal a niche differentiation between AOA and AOB, possibly driven by temperature.
Effects of illness duration and treatment resistance on grey matter abnormalities in majordepression
Authors: Serra-Blasco Maria , Portella Maria J. , Gómez-Ansón Beatriz , de Diego-Adeliño Javier , Vives-Gilabert Yolanda , Puigdemont Dolors , Granell Ester , Santos Alicia , Álvarez Enric , Pérez Víctor
Published: April 2013

Background

Findings of brain structural changes in major depressive disorder are still inconsistent, partly because some crucial clinical variables have not been taken into account.

Aims

To investigate the effect of major depressive disorder on grey matter volumes.

Method

Voxel-based morphometry was used to compare 66 patients with depression at different illness stages (22 each with first-episode, remitted-recurrent and treatment resistant/chronic depression) with 32 healthy controls. Brain volumes were correlated with clinical variables.

Results

Voxel-based morphometry showed a significant group effect in right superior frontal gyrus, left medial frontal gyrus and left cingulate gyrus (P<0.05, family wise error-corrected). Patients whose condition was treatment resistant/chronic exhibited the smallest volumes in frontotemporal areas. Longer illness duration was negatively correlated with decreases in right medial frontal cortex and left insula.

Conclusions

Frontotemporolimbic areas are smaller in the patients with severe depression and are associated with duration of illness, but not with medication patterns, suggesting negative effects of long-lasting major depressive disorder on grey matter.
Incidence and 12-Month Outcome of Non-Transient Childhood Conversion Disorder in the Uk and Ireland
Authors: Ani Cornelius , Reading Richard , Lynn Richard , Forlee Simone , Garralda Elena
Published: April 2013

Background

Little is known about conversion disorder in childhood.

Aims

To document clinical incidence, features, management and 12-month outcome of non-transient conversion disorder in under 16-year-olds in the UK and Ireland.

Method

Surveillance through the British Paediatric Surveillance Unit and Child and Adolescent Psychiatry Surveillance System.

Results

In total, 204 cases (age range 7-15 years) were reported, giving a 12-month incidence of 1.30/100 000 (95% CI 1.11-1.52). The most common symptoms were motor weakness and abnormal movements. Presentation with multiple symptoms was the norm. Antecedent stressors were reported for 80.8%, most commonly bullying in school. Most children required in-patient admission with frequent medical investigations. Follow-up at 12 months was available for 147 children, when all conversion disorder symptoms were reported as improved. Most families (91%) accepted a nonmedical explanation of the symptoms either fully or partially.

Conclusions

Childhood conversion disorder represents an infrequent but significant clinical burden in the UK and Ireland.
Medieval Prime Time
Authors: Seaman Myra J.
Published: April 2013

The author discusses a Middle English literature course she centered on the array of noncanonical texts in one fifteenth-century manuscript, Ashmole 61. In reading only noncanonical texts, students acquired a broader understanding and experience of what Middle English literature is, while expanding their sense of the methods and purposes of literary research.
Drinking Feasts and Insult Battles
Authors: Zimmerman Harold C.
Published: April 2013

By incorporating the eleventh-century colloquies of Benedictine monk Ælfric Bata into first-semester British Literature survey courses, instructors can efficiently and entertainingly confront and complicate many of the preconceived and reductive views of the medieval period that students often possess (and that canonical texts can unwittingly reinforce).
Loading Jewry into the Medieval Canon
Authors: Steinberg Theodore L.
Published: April 2013

Although there is a sizable body of medieval Hebrew poetry, that poetry is almost never included in courses on medieval literature. This neglect creates a misleading picture of the European Middle Ages. This essay attempts to show why and then to demonstrate how this poetry can be included.
Thomas Hoccleve’s Particular Appeal
Authors: Watt David
Published: April 2013

This article describes a single class devoted to an experiment in practical criticism. The experiment encourages students to recognize their own capacity as close readers when interpreting an unfamiliar fifteenth-century poem by Thomas Hoccleve. It also encourages students to reflect critically on the practice of criticism, especially the way it determines the standard by which we judge poetry.
Costs of colour change in fish: food intake and behavioural decisions
Authors: Rodgers Gwendolen M. , Gladman Nicholas , Corless Hannah , Morrell Lesley
Published: April 2013

Many animals, particularly reptiles, amphibians, fish and cephalopods, have the ability to change their body colour, for functions including thermoregulation, signalling and predator avoidance. Many fish plastically darken their body colouration in response to dark visual backgrounds, and this functions to reduce predation risk. Here, we test the hypotheses that 1) colour change in fish carries with it an energetic cost and 2) affects subsequent shoal and habitat choice decisions. We demonstrate that guppies (Poecilia reticulata) change colour in response to dark and light visual backgrounds, and that doing so carries an energetic cost in terms of food consumption. By increasing food intake, however, guppies are able to maintain growth rates and meet the energetic costs of changing colour. Following colour change, fish preferentially chose habitats and shoals that match their own body colouration, and maximise crypsis, thus avoiding the need for further colour change, but also potentially paying an opportunity cost associated with restriction to particular habitats and social associates. Thus, colour change to match the background is complemented by behavioural strategies, which should act to maximise fitness in variable environments.
Genetically and environmentally mediated divergence in lateral line morphology in the Trinidadian guppy (Poecilia reticulata)
Authors: Fischer Eva K. , Soares Daphne , Archer Kathryn R. , Ghalambor Cameron K. , Hoke Kim L.
Published: April 2013

Fish and other aquatic vertebrates use their mechanosensory lateral line to detect objects and motion in their immediate environment. Differences in lateral line morphology have been extensively characterized among species, however intraspecific variation remains largely unexplored. In addition, little is known about how environmental factors modify development of lateral line morphology. Predation is one environmental factor that can act both as a selective pressure causing genetic differences between populations, and as a cue during development to induce plastic changes. Here, we test if variation in the risk of predation within and among populations of Trinidadian guppies (Poecilia reticulata) influences lateral line morphology. We compared neuromast arrangement in wild-caught guppies from distinct high- and low-predation population pairs to examine patterns associated with differences in predation pressure. To distinguish genetic and environmental influences, we compared neuromast arrangement in guppies from different source populations reared with and without exposure to predator chemical cues. We found that the distribution of neuromasts across the body varies between populations based on both genetic and environmental factors. To the best of our knowledge, this study is the first to demonstrate variation in lateral line morphology based on environmental exposure to an ecologically relevant stimulus.
Physiological adaptations to reproduction I. Experimentally increasing litter size enhances aspects of antioxidant defence but does not cause oxidative damage in mice
Authors: Garratt Michael , Pichaud Nicolas , King Edith D. Aloise , Brooks Robert C.
Published: April 2013

Life history theory suggests that investment in reproduction can trade off against growth, longevity and both reproduction and performance later in life. One possible reason for this trade-off is that reproduction directly causes somatic damage. Oxidative stress, an overproduction of reactive oxygen species in relation to cellular defences, can correlate with reproductive investment and has been implicated as a pathway leading to senescence. This has led to the suggestion that this aspect of physiology could be an important mechanism underlying the trade-off between reproduction and lifespan. We manipulated female reproductive investment to test whether oxidative stress increases with reproduction in mice. Each female's pups were cross-fostered to produce litters of either two or eight, representing small and large levels of reproductive investment for wild mice. No differences were observed between reproductive groups at peak-lactation for several markers of oxidative stress in the heart and gastrocnemius muscle. Surprisingly, oxidative damage to proteins was lower in the livers of females with a litter size of eight than in females with two pups or non-reproductive control females. While protein oxidation decreased, activity levels of the antioxidant enzyme superoxide dismutase increased in the liver, suggesting this may be one pathway used to protect against oxidative stress. Our results highlight the need for caution when interpreting correlative relationships and suggest that oxidative stress does not increase with enhanced reproductive effort during lactation.
Glossossoma nigrior (Trichoptera: Glossosomatidae) respiration in moving fluid
Authors: Morris Mark W. L. , Hondzo Miki
Published: April 2013

Laboratory measurements of dissolved oxygen (DO) uptake by Glossosoma nigrior (Banks) were conducted in a sealed, recirculating flume under variable fluid flow velocities. Measurements were performed in similar water temperatures, DO concentrations, and fluid flow velocities as field conditions in the stream where the larvae were obtained. Total oxygen uptake by both cased larvae and corresponding cases without larvae were quantified. An increased fluid flow velocity corresponded to an increased larval DO uptake rate. Oxygen uptake by the larval cases alone was not as sensitive to changes in the Peclet (Pe) number, the dimensionless ratio of advective to diffusive DO transport, as uptake by larvae themselves. The flux of DO to larvae and their cases was up to seven times larger in a moving fluid in comparison to non-moving fluid conditions in the proximity of larvae for 0 < Pe < 175. A functional relationship was developed relating fluid flow and DO uptake across a larval case. According to the proposed quantitative relationship, Pe alone describes 91% of the variation in the DO flux to the larvae under variable fluid flow conditions. In response to fluid motion, larvae depicted two characteristic behavioral responses. When the ratio of advective DO transport to diffusive transport was low (Pe < 87), larvae occasionally abandoned their cases or spent more time partially extended from their cases. At Pe > 87, larvae typically remained in their cases. This indicates that oxygen delivery to the larvae at low Pe is insufficient to satisfy the respiratory demands of cased larvae.
Artificial activation of mature unfertilized eggs in the malaria vector mosquito, Anopheles stephensi (Diptera, Culicidae)
Authors: Yamamoto Daisuke S. , Hatakeyama Masatsugu , Matsuoka Hiroyuki
Published: April 2013

In the past decade, many transgenic lines of mosquitoes have been generated and analyzed, whereas the maintenance of a large number of transgenic lines requires a great deal of effort and cost. In vitro fertilization by an injection of cryopreserved sperm into eggs has been proven to be effective for the maintenance of strains in mammals. The technique of artificial egg activation is a prerequisite for the establishment of in vitro fertilization by sperm injection. We demonstrated that artificial egg activation is feasible in the malaria vector mosquito, Anopheles stephensi (Diptera, Culicidae). Nearly 100% of eggs dissected from virgin females immersed in distilled water darkened, similar to normally oviposited fertilized eggs. It was revealed by the cytological examination of chromosomes that meiotic arrest was relieved in these eggs about 20 min after incubation in water. Biochemical examinations revealed that MAPK (mitogen-activated protein kinase)/ERK (extracellular signal-regulated protein kinase) and MEK (MAPK/ERK kinase) were dephosphorylated similar to that in fertilized eggs. These results indicate that dissected unfertilized eggs were activated in distilled water and started development. Injection of distilled water into body cavity of the virgin blood-fed females also induced activation of a portion of eggs in the ovaries. The technique of artificial egg activation is expected to contribute to the success of in vitro fertilization in A. stephensi.
Environmental response and adaptation of glycoprotein glue within the droplets of viscous prey capture threads from araneoid spider orb-webs
Authors: Opell Brent D. , Karinshak Shannon E. , Sigler Mary A.
Published: April 2013

Viscous threads that form the prey capture spiral of araneoid orb-web retain insects that strike the web, giving a spider more time to locate and subdue them. The viscoelastic glycoprotein glue responsible for this adhesion forms the core of regularly spaced aqueous droplets, which are supported by protein axial fibers. Glycoprotein extensibility both facilitates the recruitment of adhesion from multiple droplets and dissipates the energy generated by insects struggling to free themselves from the web. Compounds in the aqueous material make droplets hygroscopic, causing both an increase in droplet volume and extensibility as humidity (RH) rises. We characterized these humidity-mediated responses at 20%, 37%, 55%, 72%, and 90% RH in two large orb-weavers, Argiope aurantia, which is found in exposed habitats, and Neoscona crucifera, which occupies forests and forest edges. The volume-specific extension of A. aurantia glycoprotein reached a maximum value at 55% RH and then declined, whereas that of N. crucifera increased exponentially through the RH range. As RH increased, the relative stress on droplet filaments at maximum extension, as gauged by axial line deflection, decreased in a linear fashion in A. aurantia, but in N. crucifer increased logarithmically, indicating that N. crucifera threads are better equipped to dissipate energy through droplet elongation. The greater hygroscopicity of A. aurantia threads equips them to function in lower RH environments and during the afternoon when RH drops, but their performance is diminished during the high RH of the morning hours. In contrast, the lower hygroscopicity of N. crucifera threads optimizes their performance for intermediate and high RH environments and during the nigh and morning. These interspecific differences support the hypothesis that viscous capture threads are adapted to the humidity regime of an orb-weaver's habitat.
Visual search in hunting archerfish shares all hallmarks of human performance
Authors: Rischawy Ingo , Schuster Stefan
Published: April 2013

Archerfish are renowned for shooting down aerial prey with water jets, but nothing is known about the ways they spot prey items in their richly structured mangrove habitats. We trained archerfish to stably assign the categories 'target' and 'background' to objects solely on the basis of non-motion cues. Unlike many other hunters archerfish are able to discriminate a target from its background in the complete absence of either self-motion or relative motion parallax cues and without using stored information about the structure of the background. This allowed us to perform matched tests to compare the ways fish and humans scan stationary visual scenes. In humans, visual search is seen as a doorway to cortical mechanisms of how attention is allocated. Fish lack a cortex and we therefore wondered if archerfish would differ from humans in their ways they scan a stationary visual scene. Our matched tests failed to disclose any differences in the dependence of response time distributions, a most sensitive indicator of the search mechanism, on number and complexity of background objects. Median and range of response times depended linearly on the number of background objects and the corresponding effective processing time per item increased similarly - about fourfold - in both humans and fish when the task was harder. Archerfish, like humans, also systematically scanned the scenery, starting with the closest object. Taken together, benchmark visual search tasks failed to disclose any difference between archerfish - who lack a cortex - and humans.
Two-dimensional electronic spectroscopy for mapping molecular photophysics
Authors: Anna Jessica M. , Song Yin , Dinshaw Rayomond , Scholes Gregory D.
Published: April 2013

We demonstrate the ability of two-dimensional electronic spectroscopy (2DES) to map ultrafast energy transfer and dynamics in two systems: the pigment–protein complex photosystem I (PSI) and aggregates of the conjugated polymer poly(3-hexylthiophene) (P3HT). A detailed description of our experimental set-up and data processing procedure is also given.
Short-Range Demonstrations of Monocular Passive Ranging Using O2 (X3Σg− → b1Σ+g) Absorption Spectra
Authors: Hawks Michael R. , Vincent R. Anthony , Martin Jacob , Perram Glen P.
Published: April 2013

The depth of absorption bands in observed spectra of distant, bright sources can be used to estimate range to the source. Experimental results are presented based on observations of the O2 X(v″ = 0) → b(v′ = 0) absorption band centered around 762 nm and the O2 X(v″ = 0) → b(v′ = 1) band around 689 nm. Range is estimated by comparing observed values of band-average absorption against predicted curves derived from either historical data or model predictions. Accuracy of better than 0.5% was verified in short-range (up to 3 km), static experiments using a high-resolution (1 cm−1) spectroradiometer. This method was also tested against the exhaust plume of a Falcon 9 rocket launched from Cape Canaveral, Florida. The rocket was launched from an initial range of 13 km and tracked for 90 s after ignition. Range error was below 2% for the first 30 s and consistent with predicted error throughout the track.
A New Method to Quantitatively Evaluate the Chemical Composition of Waterlogged Wood by Means of Attenuated Total Reflectance Fourier Transform Infrared (ATR FT-IR) Measurements Carried Out on Wet Material
Authors: Pizzo Benedetto , Pecoraro Elisa , Macchioni Nicola
Published: April 2013

Wood degradation in waterlogged conditions, although slow, is relevant in some specific contexts, such as in the case of cultural heritage preservation (e.g., ancient shipwrecks found under the water table). This decay process induces the selective depletion of the biopolymers constituting wood cell walls and mainly of their structural polysaccharides (both cellulose and hemicelluloses). Assessment of residual composition of cell walls is normally carried out using conventional chemical analyses, which, however, require elevated amounts of material. The present work reports on a new approach to quantitatively determine the residual chemical composition of wood (in terms of amount of lignin and holocellulose) and therefore its extent of degradation. This was accomplished by acquiring attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectra on material still in waterlogged conditions, which was simply placed in optical contact with the ATR crystal. Data for the calibration set were obtained by means of wet analyses, and the calibration model was based on multivariate statistical analysis through partial least square regression. Acquired spectra showed signals higher and better resolved than for dry wood. Calibration was selected after comparing two different normalization procedures and after processing signals of two different spectral ranges. Furthermore, the exclusion of some outliers led to a substantial improvement in the error parameters ( R2 and root mean square error of cross validation) associated with the calibration model, thus allowing for the selection of the best model. The stability of this best model was also established by means of the leave-more-out method. Finally, a procedure of external validation confirmed that the proposed model also could be applied to similar (for instance, belonging to Pinaceae) wood remains from other excavations.
Pre-Concentration Procedure Based on Chitosan Combined with Ionic Liquid for the Determination of Cobalt, Nickel, and Copper in Water Samples
Authors: Zawisza Beata , Sitko Rafal
Published: April 2013

An environmentally friendly analytical procedure of pre-concentration of cobalt, nickel, and copper according to the rules of green chemistry has been developed. The proposed method is based on using chitosan for sorption of trace elements from water samples. The novel modification of the sorption process is the combination of an ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6]) with chitosan. Ionic liquid partly decreases the crystallinity of the chitosan. The crystalline regions of the polymer are not accessible to metal ions. Although the ionic liquid cannot completely disrupt the crystalline domains of chitosan, it may gain in the reactive groups of the chitosan, even at the center of the particle. Consequently, the sorption of metal ions by chitosan is significantly improved. In this paper, adsorption characteristics of cobalt, nickel, and copper using newly developed sorption are studied. The effect of pH and time of chitosan activation, as well as sorption, salt concentration, some metals ion concentrations, and the amount of adsorbent on the extent of adsorption, are investigated. Chitosan with adsorbed metal ions was dissolved in acetic acid. After evaporation a solvent film formed and was then analyzed using X-ray fluorescence spectrometry (XRF). As it meets the criterion of thin samples for XRF analysis, the matrix effects can be neglected. With the proposed procedure we obtained detection limits of 7 ng mL−1 for cobalt, 5 ng mL−1 for nickel, and 4 ng mL−1 for copper.
An In-Depth Study Linking the Infrared Spectroscopy and Photoluminescence of Porous Silicon during Ambient Hydrogen Peroxide Oxidation
Authors: Caras Caley A. , Reynard Justin M. , Bright Frank V.
Published: April 2013

We carefully tailored a porous silicon (pSi) surface by oxidation with hydrogen peroxide (H2O2) to determine the time-dependent changes in nano-crystallite surface chemistries (e.g., Si–O-Si, SiHx [x = 1,2], OySiH [y=2,3], and SiOH/H2O) and their influence on the pSi photoluminescence (PL). The relationship between infrared band amplitudes and PL intensity were evaluated under H2O2 and O3 (previously studied) oxidation. The pSi surface composition under O3 and H2O2 oxidation conditions tended to, save the OySiH (y=2,3) species, approach similar values at the longest oxidation times studied, but they took very different paths in reaching these end points. Furthermore, the pSi surface compositions that exhibit maximum/minimum PL under each oxidant are very different.