bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of regulated deficit irrigation on physiology and fruit quality in apricot trees
Authors: Perez-Sarmiento F. , Alcobendas R. , Mounzer O. , Alarcon J. , Nicolas E.
Published: November 2013

The effects of regulated deficit irrigation (RDI) were studied on 9 year-old apricot-trees (Prunus armeniaca L. cv. ‘Búlida’) grafted on ‘Real Fino’ rootstock. Two irrigation treatments were established. The first, a control treatment, was irrigated to fully satisfy the crop water requirements (100% ETc) and the second, a RDI treatment, was subject to water shortage during the non-critical periods of crop development, by reducing the amount of applied irrigation water to: a) 40% of ETc from flowering until the end of the first stage of fruit growth; b) 60% of ETc during the second stage of fruit growth and c) 50% and 25% of ETc during the late postharvest period (that starts 60 days after harvesting), for the first 30 days and until the end of tree defoliation, respectively. The results indicated that the apricot tree is an appropriate species to apply RDI thanks to the clear separation between their vegetative and reproductive growths and its ability to recover the fruit diameter reduction suffered during RDI application. Furthermore, some qualitative characteristics such as the level of soluble solids, fruit taste and the colour of the fruit are enhanced. These two reasons, together with irrigation water savings of 39%, emphasize the RDI strategies as a possible solution in areas with water shortages, like the south-eastern region of Spain.
Development of relative humidity models by using optimized neural network structures
Authors: Martinez-Romero A. , Ortega J. F. , De-Juan J. A. , Tarjuelo J. M. , Moreno M. A.
Published: November 2013

Climate has always had a very important role in life on earth, as well as human activity and health. The influence of relative humidity (RH) in controlled environments (e.g. industrial processes in agro-food processing, cold storage of foods such as fruits, vegetables and meat, or controls in greenhouses) is very important. Relative humidity is a main factor in agricultural production and crop yield (due to the influence on crop water demand or the development and distribution of pests and diseases, for example). The main objective of this paper is to estimate RH [maximum (RHmax), average (RHave), and minimum (RHmin)] data in a specific area, being applied to the Region of Castilla-La Mancha (C-LM) in this case, from available data at thermo-pluviometric weather stations. In this paper Artificial neural networks (ANN) are used to generate RH considering maximum and minimum temperatures and extraterrestrial solar radiation data. Model validation and generation is based on data from the years 2000 to 2008 from 44 complete agroclimatic weather stations. Relative errors are estimated as 1) spatial errors of 11.30%, 6.80% and 10.27% and 2) temporal errors of 10.34%, 6.59% and 9.77% for RHmin, RHmax and RHave, respectively. The use of ANNs is interesting in generating climate parameters from available climate data. For determining optimal ANN structure in estimating RH values, model calibration and validation is necessary, considering spatial and temporal variability.
How to link agricultural productivity, water availability and water demand in a risk context: a model for managing hydrological risks
Authors: Gil-Sevilla M. , Garrido A. , Gomez-Ramos A.
Published: November 2013

The importance of water scarcity in irrigated agriculture in Spain provides the rationale for this paper, which analyses and evaluates the risk of water shortage on the economic result of this kind of agriculture. The main objective is to monitor this risk on a real-time basis. For this aim, we first estimated a number of regression models that explain irrigated agricultural productivity based on crop price indices, a time trend and water availability. These models, which correct for auto-correlation, yield good explanatory power. Second we carried out ex ante simulations of agricultural productivity using fitted distribution functions of water balance. The risk model framework provides the basis for a real time drought management system through a variety of distribution functions of expected economic results, which can be revised on a monthly basis before the beginning of the irrigation season. The results of the simulation show how this kind of risk model can be used to anticipate the effects of droughts and complement the hydrological models used to manage water storage in years of scarcity. Different risk profiles are identified. For example, in Genil-Cabra we found that the resilience of the system after a drought period is very high, whereas in La Plana de Castellón the risk of irrigation area abandonment is increasing year by year. In Genil-Cabra the estimated losses were 60 million euros in 2007. The models were applied to some of the most agriculturally relevant irrigation districts in Spain.
Modelling and Simulating of Risk Behaviours in Virtual Environments Based on Multi-Agent and Fuzzy Logic
Authors: Cai Linqin , Yang Zhuo , Yang Simon X. , Qu Hongchun
Published: November 2013

Due to safety and ethical issues, traditional experimental approaches to modelling underground risk behaviours can be costly, dangerous and even impossible to realize. Based on multi-agent technology, a virtual coalmine platform for risk behaviour simulation is presented to model and simulate the human-machine-environment related risk factors in underground coalmines. To reveal mine workers' risk behaviours, a fuzzy emotional behaviour model is proposed to simulate underground miners' responding behaviours to potential hazardous events based on cognitive appraisal theories and fuzzy logic techniques. The proposed emotion model can generate more believable behaviours for virtual miners according to personalized emotion states, internal motivation needs and behaviour selection thresholds. Finally, typical accident cases of underground hazard spotting and locomotive transport were implemented. The behaviour believability of virtual miners was evaluated with a user assessment method. Experimental results show that the proposed models can create more realistic and reasonable behaviours in virtual coalmine environments, which can improve miners' risk awareness and further train miners' emergent decision-making ability when facing unexpected underground situations.
Magma fracture and hybrid earthquakes in the conduit of Augustine Volcano
Authors: Buurman Helena , West Michael E.
Published: November 2013

We exploit subtle but systematic shifts in seismic waveforms to examine a 2 h cluster of repeating hybrid volcanic earthquakes preceding the first magmatic explosions at Augustine Volcano in January 2006. We extract differential P wave traveltimes of <0.01 s to determine that the source locations migrated downward by approximately 35 m. Waveform characteristics, GPS observations, and visual reports of lava effusion at the summit suggest that the earthquakes were sourced by fracturing magma in the upper conduit. As the lava cooled and degassed at the surface, the conditions in the upper conduit changed causing the zone in which magma fracture could occur to move downward through the magma column. These changes may also have been the first indicators that the conduit was becoming choked, causing a buildup in pressure that resulted in the large magmatic explosions that followed 36 h later.
Spliceosome
Authors: Anthony Kelsey C , Pomeranz Krummel Daniel
Published: November 2013

The removal of noncoding regions or introns and the splicing together of the protein‐coding regions or exons from
precursor messenger ribonucleic acid (pre‐mRNA)
transcripts is fundamental to metzoan cell development, as well as its maintenance. The nuclear process of pre‐mRNA splicing is a complex phenomenon catalysed by the ‘spliceosome’. The spliceosome consists of greater than a hundred protein and RNA molecules. Integral to the spliceosome are five RNA–protein complexes, the U1, U2, U4, U5 and U6 small nuclear ribonucleoproteins (snRNPs). The numerous proteins and the U snRNPs that make up the spliceosome come on and off during the spliceosome's reaction cycle. This article places an emphasis on our current understanding of the dynamics, composition and structure of the spliceosome.

Key Concepts:

Specific sequences defining the boundaries between a protein‐coding gene's noncoding regions or introns and its protein‐coding regions or exons are recognised by components of the pre‐mRNA splicing ‘machinery’ – the spliceosome.

The spliceosome is composed of a large number of RNA and protein molecules. The protein subunits have diverse domain structures, whereas the RNA subunits form hydrogen bonding or base‐pairing interactions with critical sequences in a pre‐mRNA as well as with each other.

The spliceosome reaction cycle involves an ordered assembly onto a pre‐mRNA transcript to ultimately catalyse two
trans
‐esterification reactions that result in the removal or excision of an intron and the splicing together of two exons.

Integral to the function of the spliceosome are five U snRNPs, each of which has a single RNA and 3–12 protein constituents including a homologous set of proteins (Sm or LSm) that forms a structural unit critical to the biogensis and integrity of each U snRNP.

The U1, U2, U4 and U5 snRNPs all have a common core structure that consists of seven Sm proteins which assemble around a short U‐rich single‐stranded RNA sequence (the Sm site) present in the U1, U2, U4 and U5 snRNAs to form a heptameric ring with the single‐stranded RNA Sm site leafing through the central hole.

Metazoan U1 snRNP functions to initiate the assembly of the spliceosome onto a pre‐mRNA transcript; its single RNA subunit (U1 snRNA) forms a cruciform‐like structure onto which the Sm proteins assemble to form the Sm core, while its three additional U‐specific proteins (U1‐A, U1‐70K, and U1‐C) participate in particle specific functions – including recognition of a pre‐mRNA transcripts 5' splice site sequence.
Manihot esculenta
(Cassava)
Authors: Beeching John R
Published: November 2013

Cassava (

Manihot esculenta

) is the world's seventh most important crop in terms of production and provides the staple food for more than 500 million people in the humid tropics. Owing to its ability to survive adverse environmental conditions and its high efficiency at fixing CO
2
into carbohydrate compared with other crops, cassava has a vital role to play in a planet faced with the interrelated challenges of population growth, food scarcity, fuel shortage and climate change. Despite these advantages, cassava storage roots are nutritionally deficient, cyanogenic, deteriorate rapidly on harvest and the crop is prone to pests and diseases. However, through exploiting germplasm diversity, breeding and biotechnology many of these challenges can be addressed for the benefit of producers, processers and consumers.

Key Concepts:

Cassava storage roots are the staple food of hundreds of millions in the humid tropics.

Owing to its drought tolerance and ability to grow on impoverished soils cassava is a vitally important famine reserve crop in sub‐Saharan Africa.

Breeding and biotechnology can address the current limitations of cassava in order to make it a more productive, versatile and nutritious crop.

Enhanced germplasm combined with improved agronomic practice can enable cassava to make a significant contribution to global food security.

In addition to food, cassava is processed into industrial products and is of increasing interest for biofuel production.
Osteosarcoma: Genetics of Inherited Susceptibility
Authors: Mirabello Lisa
Published: November 2013

Osteosarcoma (OS) is the most common primary malignant bone tumour that typically occurs in adolescents and young adults. OS incidence has been related to growth and height, age, gender, ethnicity, certain inherited cancer predisposition syndromes, abnormal bone growth and therapeutic radiation. However, most cases are sporadic (not associated with an inherited syndrome) and no specific genetic or environmental predisposing factor has been identified. A common genetic susceptibility locus has not been found.

Germline genetics refers to
deoxyribonucleic acid (DNA)
sequence changes that are inherited and present in all cells of the body versus an acquired or somatic mutation. Germline candidate gene association studies have identified several common single nucleotide polymorphisms (SNPs) associated with risk of OS, including genes important in growth, cell cycle checkpoint control and tumour immunity. Recently, the first genome‐wide association study was conducted and further expands our understanding of the germline genetics of OS.

Key Concepts:

Epidemiologic studies have provided many important clues about the aetiology of OS, including an association with bone growth, which have directed much of the search for candidate genes associated with risk of OS.

OS is associated with several rare inherited cancer predisposition syndromes (Li–Fraumeni syndrome, hereditary bilateral retinoblastoma, Bloom, Werner, Rothmund Thomson syndromes, and Diamond–Blackfan anemia) that are caused by highly penetrant germline mutations. These syndromes are not a common cause of OS.

Candidate gene association studies have suggested several polymorphisms associated with risk of OS; SNP associations in the following candidate genes have been replicated in two or more studies:
IGF2R
,
FGFR3
,
MDM2
,
TGFBR1
and
CTLA‐4
.

An agnostic genome‐wide association study has found two novel loci associated with risk of OS:
GRM4
gene and the 2p25.2 chromosomal region.

Studies are needed to expand these genetic association findings to more ethnic groups and in larger samples sizes to determine if these are stable associations.
Genetics of Human Social Behaviour
Authors: Ebstein Richard P , Melman Rachel‐Bachner , Lai Poh San , Monakhov Mikhail , Chew Soo Hong
Published: November 2013

Our species,

Homo sapiens

, displays the most multifaceted social behaviour ever to evolve, far exceeding all other social species from eusocial insects to our nearest primate relatives. This intricate social behaviour underpins our remarkable success in evolving from cooperation in small bands of hunter gatherers ∼100 000 years ago to the apex of globalisation that characterises the twenty‐first century political and economic institutions. Although our social brains are remarkably flexible, a significant part of our social behaviour is hardwired and embedded in our deoxyribonucleic acid (DNA) code. The human mind is not a
tabula rasa
, and our behaviour is constrained to a significant extent by our genes. That is not to say that environment is unimportant; along with the genetic code, the interaction between environment and genes makes us who we are. The overall role of genes and environment is revealed firstly by twin studies and then by leveraging the human genome project. The latter enables the identification of specific genes that, together with the environment, contribute to individual differences in human social behaviour.

Key Concepts:

Twin studies demonstrate that both genes and environment more or less equally contribute to individual differences in almost all human behaviour.

Diverse social phenotypes such as pair bonding, parenting, fairness, altruism, trust, economic behaviour, political attitudes and others are partially hardwired.

Two nonapeptide hormones, oxytocin (OT) and arginine vasopressin (AVP), are paramount human social hormones and have been the focus of attention of studies based on translational evidence from rodents, especially the vole.

Candidate gene association studies have provisionally shown that genes in the AVP and OT neural pathways also contribute to human social behaviour.

Other neural pathways and their associated genes, especially dopamine and serotonin, have also been identified and linked to human social behaviour.

Neuroeconomics, which employs the principles and techniques of behavioural economic games, paves the way towards finding common polymorphisms by employing economic games as phenotypes in molecular genetic studies.

Genome‐wide association studies (GWAS), which are agnostic and hypothesis free, offer the opportunity to identify many novel genes contributing to human social behaviour.

To leverage the power of GWAS and discover new ‘social’ genes, sharpened phenotypes such as incentivised laboratory ‘games’ need to be employed. Such laboratory‐based phenotypes strategically go beyond pencil and paper questionnaires ideally employed in panel studies and surveys.
Gene Therapy for Parkinson Disease
Authors: Choong Chi‐Jing , Mochizuki Hideki
Published: November 2013

Parkinson disease (PD) presents several features including the relative selective localisation of pathology to the substantia nigra and well‐defined motor symptoms caused by dopaminergic degeneration that make it an ideal target for gene therapy. Parallel progress in viral vector systems has made it possible to deliver therapeutic genes directly into the brain with reasonable safety. To date, gene therapy for PD is mainly based on symptomatic approaches that involve enzyme‐replacement strategies to restore dopamine (DA) levels or correct the functional perturbation of the basal ganglia caused by DA loss and disease‐modifying approaches that depend on delivery of neurotrophic factors and alteration of genetic causes of PD to protect neuronal functions and slow down or even halt disease progression. As supported by the increasing preclinical and clinical evidence, gene therapy may be a promising treatment to relieve the disabling nature of PD.

Key Concepts:

Gene therapy for PD focusses on symptomatic approach that involves enzyme‐replacement strategy and disease‐modifying approach that depends on addition of neurotrophic factors.

Intrastriatal expression of genes TH, AADC and GCH, the three key enzymes for DA biosynthesis, can compensate for the decreased levels of DA in PD patients.

An approach aiming at modulating STN activity is done by delivering gene GAD, the rate‐limiting enzyme for GABA synthesis.

Neurotrophic factors including GDNF and NTN have potent trophic activity on dopaminergic neurons and play essential roles in the protection and restoration of neuronal cells.

Novel viral vectors are capable of delivering genetic materials to target cells and inducing sustained transgene expression.

Four candidates for PD gene therapy including EIAV‐AADC‐TH‐GCH, AAV2‐AADC, AAV2‐GAD and AAV2‐NTN are currently under clinical trial evaluation.
Personalised Cancer Medicine: Fulfilling the Promise
Authors: Olzscha Heidi , New Maria , La Thangue Nicholas B
Published: November 2013

The continual increase in global cancer incidence has created a huge need for new and more effective cancer drugs. However, success is often limited by the heterogeneity among patients, which frequently leads to the failure of patients to respond to a drug together with toxic side effects. Personalised medicine uses our advancing molecular understanding of disease to provide the most efficient medical care for individual patients, depending on their unique clinical, genetic and environmental state. Various types of biomarkers assist this process by enabling prediction of clinical outcome on treatment, or measuring effect of treatment which is then correlated with a clinical endpoint. Omics technologies such as genomics, transcriptomics and proteomics are crucially important in the personalised medicine approach as they enable the analysis of multiple and large datasets to stratify patients into responder subgroups.

Key Concepts:

The increase in global cancer incidence calls for more effective therapies.

Personalised medicine identifies patients who respond differently to treatment.

Genetic and molecular heterogeneity in tumours contributes to variable treatment response.

Biomarker development is crucial for personalised cancer medicine.

Biomarkers can be prognostic, predictive and pharmacodynamic.

Molecular imaging enables the response to treatment to be visualised.

High‐throughput omics technologies allow analysis of large amounts of information on the healthy and diseased states.
X Chromosome and Spermatogenesis Defects
Authors: Stouffs Katrien , Lissens Willy
Published: November 2013

Spermatogenesis, the process through which mature spermatozoa are formed, is a complex process requiring a very strict regulation. More than 2000 genes are involved in spermatogenesis. Part of these genes has a unique function during spermatogenesis. The X chromosome is special because only one copy is present in men, whereas women have two X copies. Moreover, the mammalian X chromosome is enriched for testis‐specific genes. This makes the X chromosome particularly interesting in view of male infertility. Although multiple studies have tried to identify mutations in X‐linked spermatogenesis genes, the number of causative mutations detected so far remains low. Nowadays, new techniques allow the analysis of the complete X chromosome in a single experiment. Within the next few years, the knowledge on the role of the X chromosome in male infertility (and consequently also in spermatogenesis) will increase.

Key Concepts:

Men are hemizygous for X‐chromosomal genes: men only have one X chromosome; mutations in X‐linked genes (might) have an immediate impact on spermatogenesis.

Spermatogenic failure can be caused by genetic defects.

The X chromosome is enriched for spermatogenesis genes.

Many multi‐copy genes involved in spermatogenesis are also expressed in cancer cell lines. Therefore, these are often described as cancer‐testis (CT) genes.

Many X‐linked genes that are preferentially expressed in testis have not (yet) been evaluated in view of male infertility.

The study of individual genes in view of male infertility has been disappointing because it is a time‐consuming process and often no differences with normal controls have been detected.
Electron‐Deficient Alloxazinium Salts: Efficient Organocatalysts of Mild and Chemoselective Sulfoxidations with Hydrogen Peroxide
Authors: Ménová Petra , Dvořáková Hana , Eigner Václav , Ludvík Jiří , Cibulka Radek
Published: November 2013

A series of substituted alloxazinium perchlorates has been prepared and tested as catalysts for the oxidation of sulfides to sulfoxides with hydrogen peroxide. The logarithms of the observed rate constants of thioanisole oxidation correlate with the Hammett σ constants of the substituents on the alloxazinium catalysts, as well as with their reduction potentials E0′ and their pKR+ values, representing the alloxazinium salt/pseudobase equilibrium. The stronger the electron‐withdrawing substituent, the more efficient is the alloxazinium catalyst. The alloxazinium salts with a cyano or trifluoromethyl group in position 8 proved to be the most efficient, operating at room temperature at small loadings, down to 0.1 mol%, achieving turnover number values of up to 640 and acceleration by a factor of 350 relative to the non‐catalyzed oxidation. The 8‐cyanoalloxazinium perchlorate was evaluated as the best catalyst; however, due to its relatively good accessibility, the 8‐(trifluoromethyl)alloxazinium perchlorate seems to be the catalyst of choice for sulfoxidations with hydrogen peroxide. It was successfully tested for the sulfoxidation of a series of aliphatic and aromatic sulfides on a preparative scale. It produced the corresponding sulfoxides in quantitative conversions and with high isolated yields (87–98%). No over‐oxidation to sulfone was ever observed.

magnified image
A large‐scale nationwide newborn screening program for pompe disease in Taiwan: Towards effective diagnosis and treatment
Authors: Yang Chia‐Feng , Liu Hao‐Chuan , Hsu Ting‐Rong , Tsai Fang‐Chih , Chiang Sheng‐Fong , Chiang Chuan‐Chi , Ho Hui‐Chen , Lai Chih‐Jou , Yang Tsui‐Feng , Chuang Sung‐Yin , Lin Ching‐Yuang , Niu Dau‐Ming
Published: November 2013

The aim of this study was to: (a) analyze the results of a large‐scale newborn screening program for Pompe disease, and (b) establish an effective diagnostic protocol to obtain immediate, valid diagnosis of infantile‐onset Pompe disease (IOPD) to promote earlier treatment and better outcomes. In this study, 402,281 newborns were screened for Pompe disease from January 1, 2008 to May 1, 2012. Infants with low acid α‐glucosidase (GAA) activity were referred to Taipei Veterans General Hospital for diagnostic confirmation. Physical examination, biochemical parameter (creatine kinase [CK], alanine transaminase, aspartate aminotransferase, and lactate dehydrogenase), and echocardiogram assessments were performed immediately to effectively differentiate IOPD from suspected late‐onset Pompe disease (LOPD) or false‐positive cases with pseudodeficiency mutation. Six infants with IOPD all presented with hypotonia, extremely low GAA enzyme activity (≤0.5 µmol/L/hr) in initial dried blood spot analysis, high CK (≥250 U/L), and high left ventricular mass index (LVMI, ≥80 g/m2). By analyzing these parameters, IOPD was distinguished effectively and immediately from suspected LOPD and false‐positive cases. Except for the first referred case, five of the infants with IOPD received first‐time enzyme replacement therapy (ERT) within 4 hr of admission and exhibited marked improvement. Our findings indicate that certain clinical manifestations (hypotonia, high CK, enlarged LVMI, and extremely low GAA enzyme activity in initial dried blood spot analysis) can help in the rapid and effective differentiation of patients with IOPD from other patient with low GAA activity. Such differentiation allows for the early application of first‐time ERT and leads to better outcomes. © 2013 Wiley Periodicals, Inc.
Phenotypic and molecular characterization of 19q12q13.1 deletions: A report of five patients
Authors: Chowdhury Shimul , Bandholz Anne M. , Parkash Sandhya , Dyack Sarah , Rideout Andrea L. , Leppig Kathleen A. , Thiese Heidi , Wheeler Patricia G. , Tsang Marilyn , Ballif Blake C. , Shaffer Lisa G. , Torchia Beth S. , Ellison Jay W. , Rosenfeld Jill A.
Published: November 2013

A syndrome associated with 19q13.11 microdeletions has been proposed based on seven previous cases that displayed developmental delay, intellectual disability, speech disturbances, pre‐ and post‐natal growth retardation, microcephaly, ectodermal dysplasia, and genital malformations in males. A 324‐kb critical region was previously identified as the smallest region of overlap (SRO) for this syndrome. To further characterize this microdeletion syndrome, we present five patients with deletions within 19q12q13.12 identified using a whole‐genome oligonucleotide microarray. Patients 1 and 2 possess deletions overlapping the SRO, and Patients 3–5 have deletions proximal to the SRO. Patients 1 and 2 share significant phenotypic overlap with previously reported cases, providing further definition of the 19q13.11 microdeletion syndrome phenotype, including the first presentation of ectrodactyly in the syndrome. Patients 3–5, whose features include developmental delay, growth retardation, and feeding problems, support the presence of dosage‐sensitive genes outside the SRO that may contribute to the abnormal phenotypes observed in this syndrome. Multiple genotype–phenotype correlations outside the SRO are explored, including further validation of the deletion of WTIP as a candidate for male hypospadias observed in this syndrome. We postulate that unique patient‐specific deletions within 19q12q13.1 may explain the phenotypic variability observed in this emerging contiguous gene deletion syndrome. © 2013 Wiley Periodicals, Inc.
A Palladium‐Nanoparticle and Silicon‐Nanowire‐Array Hybrid: A Platform for Catalytic Heterogeneous Reactions
Authors: Yamada Yoichi M. A. , Yuyama Yoshinari , Sato Takuma , Fujikawa Shigenori , Uozumi Yasuhiro
Published: November 2013

We report the development of a silicon nanowire array‐stabilized palladium nanoparticle catalyst, SiNA‐Pd. Its use in the palladium‐catalyzed Mizoroki‐Heck reaction, the hydrogenation of an alkene, the hydrogenolysis of nitrobenzene, the hydrosilylation of an α,β‐unsaturated ketone, and the C‐H bond functionalization reactions of thiophenes and indoles achieved a quantitative production with high reusability. The catalytic activity reached several hundred‐mol ppb of palladium, reaching a TON of 2 000 000.
Hybrid Surfactant Systems with Inorganic Constituents
Authors: Polarz Sebastian , Landsmann Steve , Klaiber Alexander
Published: November 2013

Surfactants are molecules of enormous scientific and technological importance, which are widely used as detergents, emulsifiers, and for the preparation of diverse nanostructures. Their fascinating ability to form self‐organized structures, such as micelles or liquid crystals, originate from their amphiphilic architecture—a polar head group linked to a hydrophobic chain. While almost all known surfactants are organic, a new family of surfactants is now emerging, which combines amphiphilic properties with the advanced functionality of transition‐metal building blocks, for example, redox or catalytic activity and magnetism. These hybrid surfactants exhibit novel self‐organization features because of the unique size and electronic properties of the metal‐containing entities.
Effect of Growth Stage on Essential‐Oil Yield and Composition of Daucus sahariensis
Authors: Flamini Guido , Smaili Tahar , Zellagui Amar , Gherraf Noureddine , Cioni Pier Luigi
Published: November 2013

The essential oils obtained by hydrodistillation from Daucus sahariensis Murb. harvested at three different growth stages were characterized by GC/MS analysis. In total, 88 compounds were identified, with myristicin (29.8–51.7%), myrcene (6.7–31.1%), α‐pinene (11.6–14.8%), and limonene (5.3–11.5%) as main constituents. Monoterpene hydrocarbons were the most represented compounds in the oils of the plant samples collected during the flower‐budding and full‐flowering periods. On the contrary, during the fruiting stage, the oils were dominated by phenylpropanoids. The essential oils were subject of considerable variation in their composition during the various developmental stages, particularly concerning the content of myrcene that decreased significantly passing from the vegetative to the fruiting stage. Conversely, for myristicin, the opposite trend was observed. Furthermore, the essential‐oil yields were quite low during the flower‐budding phase (0.27%), but rapidly increased during plant development (0.63 and 0.68% for the flowering and fruiting phases, resp.).
Using annexin V‐coated magnetic beads to capture active tissue factor‐bearing microparticles from body fluids
Authors: Gieseler Frank , Gamperl Hans , Theophil Frederike , Stenzel Inga , Quecke Tabea , Ungefroren Hendrik , Lehnert Hendrik
Published: November 2013

Microparticles, found in all body fluids including peripheral blood, are important elements that regulate cellular interactions under both physiological and pathological conditions. They play an important role in blood clot formation and increased cell aggregation. However, little is known about the components of the microparticles and their mechanism of action. A method to quantify and assess the underlying mechanism of action of microparticles in pathologies is therefore desirable. We present a specific method to isolate cell‐derived microparticles from malignant effusions using annexin V‐coated magnetic microbeads. The microparticles can be detected by flow cytometry. Our results show that the microparticles can be isolated with >80% specificity when bound to annexin V‐coated magnetic beads, which was originally developed for the detection of apoptotic cells. We also show that the isolated microparticles were still functionally active and can be used for further analysis. Thus, our method enables isolation as well as structural and functional characterisation of the microparticles which are produced in numerous patho‐physiological situations. This should help gain a deeper insight into various disease situations, which in turn should pave the way for the development of novel drugs and specific therapy strategies.
The Series of Rare Earth Complexes [Ln2Cl6(μ‐4,4′‐bipy)(py)6], Ln=Y, Pr, Nd, Sm‐Yb: A Molecular Model System for Luminescence Properties in MOFs Based on LnCl3 and 4,4′‐Bipyridine
Authors: Matthes Philipp R. , Nitsch Jörn , Kuzmanoski Ana , Feldmann Claus , Steffen Andreas , Marder Todd B. , Müller‐Buschbaum Klaus
Published: November 2013

A series of 12 dinuclear complexes [Ln2Cl6(μ‐4,4′‐bipy)(py)6], Ln=Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, (1–12, respectively) was synthesized by an anhydrous solvothermal reaction in pyridine. The complexes contain a 4,4′‐bipyridine bridge and exhibit a coordination sphere closely related to luminescent lanthanide MOFs based on LnCl3 and 4,4‐bipyridine. The dinuclear complexes therefore function as a molecular model system to provide a better understanding of the luminescence mechanisms in the Ln‐N‐MOFs [Ln2Cl6(4,4′‐bipy)3]⋅2(4,4′‐bipy). Accordingly, the luminescence properties of the complexes with Ln=Y, Sm, Eu, Gd, Tb, Dy, (1, 4–8) were determined, showing an antenna effect through a ligand–metal energy transfer. The highest efficiency of luminescence is observed for the terbium‐based compound 7 displaying a high quantum yield (QY of 86 %). Excitation with UV light reveals typical emission colors of lanthanide‐dependent intra 4f–4f‐transition emissions in the visible range (TbIII: green, EuIII: red, SmIII: salmon red, DyIII: yellow). For the GdIII‐ and YIII‐containing compounds 6 and 1, blue emission based on triplet phosphorescence is observed. Furthermore, ligand‐to‐metal charge‐transfer (LMCT) states, based on the interaction of Cl− with EuIII, were observed for the EuIII compound 5 including energy‐transfer processes to the EuIII ion. Altogether, the model complexes give further insights into the luminescence of the related MOFs, for example, rationalization of Ln‐independent quantum yields in the related MOFs.
Self‐Association of an Enantiopure β‐Pentapeptide in Nematic Liquid Crystals
Authors: Bortolus Marco , Wright Karen , Toffoletti Antonio , Toniolo Claudio , Maniero Anna Lisa
Published: November 2013

Herein, we report for the first time that nematic liquid‐crystalline environments drive the reversible self‐aggregation of an enantiopure β‐pentapeptide into oligomers with a well‐defined structure. The peptide contains four (1S,2S)‐2‐aminocyclopentane carboxylic acid (ACPC) residues and the paramagnetic β‐amino acid (3R,4R)‐4‐amino‐1‐oxyl‐2,2,5,5‐tetramethylpyrrolidine‐3‐carboxylic acid (POAC). The structure of the oligomers was investigated by electron paramagnetic resonance (EPR) spectroscopy, which allowed us to obtain the intermonomer distance distribution in the aggregates as a function of peptide concentration in two nematic liquid crystals, E7 and ZLI‐4792. The aggregates were modeled on the basis of the EPR data, and their orientation and order in the nematic phase were studied by the surface tensor method.
Experimental design for the optimization and robustness testing of a liquid chromatography tandem mass spectrometry method for the trace analysis of the potentially genotoxic 1,3‐diisopropylurea
Authors: Székely György , Henriques Bruno , Gil Marco , Alvarez Carlos
Published: November 2013

This paper discusses a design of experiments (DoE) assisted optimization and robustness testing of a liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) method development for the trace analysis of the potentially genotoxic 1,3‐diisopropylurea (IPU) impurity in mometasone furoate glucocorticosteroid. Compared to the conventional trial‐and‐error method development, DoE is a cost‐effective and systematic approach to system optimization by which the effects of multiple parameters and parameter interactions on a given response are considered. The LC and MS factors were studied simultaneously: flow (F), gradient (G), injection volume (Vinj), cone voltage (Econ), and collision energy (Ecol). The optimization was carried out with respect to four responses: separation of peaks (Sep), peak area (Ap), length of the analysis (T), and the signal‐to‐noise ratio (S/N). An optimization central composite face (CCF) DoE was conducted leading to the early discovery of carry‐over effect which was further investigated in order to establish the maximum injectable sample load. A second DoE was conducted in order to obtain the optimal LC‐MS/MS method. As part of the validation of the obtained method, its robustness was determined by conducting a fractional factorial of resolution III DoE, wherein column temperature and quadrupole resolution were considered as additional factors. The method utilizes a common Phenomenex Gemini NX C‐18 HPLC analytical column with electrospray ionization and a triple quadrupole mass detector in multiple reaction monitoring (MRM) mode, resulting in short analyses with a 10‐min runtime. The high sensitivity and low limit of quantification (LOQ) was achieved by (1) MRM mode (instead of single ion monitoring) and (2) avoiding the drawbacks of derivatization (incomplete reaction and time‐consuming sample preparation). Quantitatively, the DoE method development strategy resulted in the robust trace analysis of IPU at 1.25 ng/mL absolute concentration corresponding to 0.25 ppm LOQ in 5 g/l mometasone furoate glucocorticosteroid. Validation was carried out in a linear range of 0.25‐10 ppm and presented a relative standard deviation (RSD) of 1.08% for system precision. Regarding IPU recovery in mometasone furoate, spiked samples produced recoveries between 96 and 109 % in the range of 0.25 to 2 ppm. Copyright © 2013 John Wiley & Sons, Ltd.
Substituted Phenanthrolines as Antennae in Luminescent EuIII Complexes
Authors: Akerboom Sebastiaan , van den Elshout Jos J. M. H. , Mutikainen Ilpo , Siegler Maxime A. , Fu Wen Tian , Bouwman Elisabeth
Published: November 2013

Eight novel europium(III)‐based coordination compounds with 1,10‐phenanthroline (phen) ligands with a chloro, methoxy, ethoxy, cyano, carboxylic acid, methyl carboxylate, ethyl carboxylate, and amino substituent on the 2‐position have been prepared in yields ranging from 43 to 89 %. Additionally, one lanthanum(III) coordination compound of 2‐amino‐1,10‐phenanthroline has been isolated. All compounds have the general formula [Ln(L)2(NO3)3], except for the compound with the carboxylate ligand, which has the formula [Eu(O2Cphen)3]. Three of the EuIII complexes as well as the LaIII compound crystal structures have been determined, all of which show similar N4O6 coordination spheres for the LnIII ion. Seven compounds exhibit bright luminescence that is characteristic of EuIII upon irradiation with near‐UV radiation, thus indicating efficient ligand‐to‐metal energy transfer. The complex with 2‐amino‐1,10‐phenanthroline is nonluminescent. The solid‐state photoluminescent quantum yields range from 10 to 79 %, and the luminescence lifetimes vary from 0.43 to 1.57 ms. Analysis of the spectral intensities with the Judd–Ofelt theory shows a significant contribution of nonradiative processes that quench the luminescence of the 5D0 level on EuIII.
Design, Synthesis, and Organocatalytic Activity of N‐Heterocyclic Carbenes Functionalized with Hydrogen‐Bond Donors in Enantioselective Reactions of Homoenolates
Authors: Nawaz Faisal , Zaghouani Mehdi , Bonne Damien , Chuzel Olivier , Rodriguez Jean , Coquerel Yoann
Published: November 2013

A focused library of chiral imidazolinium salts functionalized with urea‐type hydrogen‐bond donor moieties has been prepared from the chiral pool. The corresponding N‐heterocyclic carbenes were evaluated as organocatalysts in three enantioselective reactions involving homoenolate intermediates generated from enals. The catalysts proved competent in enantioselective cyclopentannulation and γ‐lactonization reactions, a premiere for imidazoline‐based NHCs. This work conveys some new ideas and knowledge on the concepts of bifunctional enantioselective organocatalysis applied to NHCs.
Polyoxometalate‐Graphene Nanocomposite Modified Electrode for Electrocatalytic Detection of Ascorbic Acid
Authors: Zhang Weiying , Du Dan , Gunaratne Don , Colby Robert , Lin Yuehe , Laskin Julia
Published: November 2013

Phosphomolybdate functionalized graphene nanocomposite (PMo12‐GS) has been successfully formed on a glassy carbon electrode (GCE) for the detection of ascorbic acid (AA). The obtained PMo12‐GS modified GCE, was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, scanning electron microscopy (SEM) and Fourier transform infrared (FT‐IR) spectroscopy and compared with GCE, GS modified GCE, and PMo12 modified GCE. It shows an increased current and a decrease in over‐potential of ∼210 mV. The amperometric signals are linearly proportional to the AA concentration in a wide concentration range from 1×10−6 M to 8×10−3 M, with a detection limit of 0.5×10−6 M. The PMo12‐GS modified electrode was employed for the determination of the AA level in vitamin C tablets, with recoveries between 96.3 and 100.8 %.
The DinB•RecA complex of Escherichia coli mediates an efficient and high‐fidelity response to ubiquitous alkylation lesions
Authors: Cafarelli Tiziana M. , Rands Thomas J. , Godoy Veronica G.
Published: November 2013

Alkylation DNA lesions are ubiquitous, and result from normal cellular metabolism as well as from treatment with methylating agents and chemotherapeutics. DNA damage tolerance by translesion synthesis DNA polymerases has an important role in cellular resistance to alkylating agents. However, it is not yet known whether Escherichia coli (E. coli) DNA Pol IV (DinB) alkylation lesion bypass efficiency and fidelity in vitro are similar to those inferred by genetic analyses. We hypothesized that DinB‐mediated bypass of 3‐deaza‐3‐methyladenine, a stable analog of 3‐methyladenine, the primary replication fork‐stalling alkylation lesion, would be of high fidelity. We performed here the first kinetic analyses of E. coli DinB•RecA binary complexes. Whether alone or in a binary complex, DinB inserted the correct deoxyribonucleoside triphosphate (dNTP) opposite either lesion‐containing or undamaged template; the incorporation of other dNTPs was largely inefficient. DinB prefers undamaged DNA, but the DinB•RecA binary complex increases its catalytic efficiency on lesion‐containing template, perhaps as part of a regulatory mechanism to better respond to alkylation damage. Notably, we find that a DinB derivative with enhanced affinity for RecA, either alone or in a binary complex, is less efficient and has a lower fidelity than DinB or DinB•RecA. This finding contrasts our previous genetic analyses. Therefore, mutagenesis resulting from alkylation lesions is likely limited in cells by the activity of DinB•RecA. These two highly conserved proteins play an important role in maintaining genomic stability when cells are faced with ubiquitous DNA damage. Kinetic analyses are important to gain insights into the mechanism(s) regulating TLS DNA polymerases. Environ. Mol. Mutagen. 55:92–102, 2014. © 2013 Wiley Periodicals, Inc.
Modified Porous Zr–Mo Mixed Oxides as Strong Acid Catalysts for Biodiesel Production
Authors: Zhang Qiuyun , Li Hu , Liu Xiaofang , Qin Wenting , Zhang Yuping , Xue Wei , Yang Song
Published: November 2013

A series of modified Zr–Mo oxide‐based solid‐acid catalysts were prepared by using the corresponding chlorides as oxide precursors and low‐cost monofunctional carboxylic acids such as stearic acid, palmitic acid, myristic acid, and lauric acid as modifiers. The catalysts were characterized by thermogravimetric (TG) analysis, X‐ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), ammonia temperature programmed desorption (NH3‐TPD), scanning electron microscopy (SEM), and nitrogen adsorption–desorption. It was demonstrated that the modified catalysts possessed grainy structures and loose honeycombed surfaces that exhibit high acid intensity and surface area. In particular, Zr–Mo oxide modified with stearic acid showed the best catalytic performance for the esterification of oleic acid with methanol in comparison to other mixed metal oxides, and it was selected for further experimental studies. Under the optimal reaction conditions of molar ratio of 10:1 methanol/oleic acid, 4 wt % of catalyst loading, 2 h reaction time, and 180 °C reaction temperature, the conversion of oleic acid reached 94.2 %. Moreover, the employed solid‐acid catalysts could also facilitate carbohydrate transformation, and could be easily separated from the reaction system and reused over at least six runs without significant loss of activity.
Modelling biological regions from multi‐species and environmental data
Authors: Foster S.D. , Givens G.H. , Dornan G.J. , Dunstan P.K. , Darnell R.
Published: November 2013

Partitioning the environment into areas that appear to contain similar biological content is useful for investigating questions of distribution and habitat and for helping guide resource conservation and utilization. The statistical task requires relating presence/absence data from multiple species to co‐located environmental data. In this article, we introduce a statistical modelling framework that models the environment as a set of regions where the vector of probabilities of observing a set of species remains approximately constant within a region and distinct between regions. This is achieved within a mixture‐of‐experts model framework, which treats the region type as a latent variable whose distribution varies as a function of the environment. This approach allows us to predict probabilities of region types for sampled and unsampled locations. The model synthesizes biological and environmental data, incorporating both in a single likelihood that enables propagation of uncertainty through the entire model. The method is demonstrated using a synthetic example and data from a survey of fish from the North West Shelf, which is located off Western Australia. An R package, RCPmod, which implements the methods described in this article, is available from CRAN. Copyright © 2013 John Wiley & Sons, Ltd.
Lithospheric structure beneath the High Lava Plains, Oregon, imaged by scattered teleseismic waves
Authors: Chen Chin‐Wu , James David E. , Fouch Matthew J. , Wagner Lara S.
Published: November 2013

We compute high‐resolution seismic images from scattered wavefield to detect discontinuities beneath the High Lava Plains (HLP), using data recorded at a dense broadband array. Our images of the HLP and surrounding regions reveal (1) a prominent Moho discontinuity with varying depth, with thinnest crust of 35 km beneath the volcanic track, and thickened crust of ∼45 km beneath the Owyhee Plateau (OP); (2) distinct intracrustal velocity reversals beneath regions of pre‐2.0 Ma volcanism and within the OP; and (3) intermittent negative velocity discontinuities in the uppermost mantle beneath regions of Holocene volcanism and volcanic centers near Steens Mountain and Newberry volcano. These features exhibit remarkable similarity with those seen in the surface wave tomography and Ps receiver functions. We fail to find evidence for a ubiquitous regional lithosphere‐asthenosphere boundary (LAB). In concert with petrological constraints on the equilibration depths of primitive basaltic melts, our results suggest that the present‐day HLP mantle lithosphere is thin or absent, perhaps a consequence of episodes of extensive mantle inflow, lithospheric extension, and possibly melting induced by rapid slab rollback and trench retreat. It remains possible, however, that strong E‐W seismic anisotropy reported across this region may reduce the effective S‐wave velocity contrast to render the LAB less detectable. In contrast, the Owyhee Plateau exhibits a clear LAB, consistent with it being a block of older preexisting lithosphere. Our images demonstrate the complexity of mantle dynamics in the Cascadian back‐arc and the close casual link between subduction‐related processes and the origin of HLP volcanism.