bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cryptosporidiosis
Authors: Bhaskaran Archana , White A Clinton 
Published: March 2009

AbstractCryptosporidiumspp. are protozoans known but the pathogenic role in human infection has been recognized only in the past few decades. Transmission is through the fecal‐oral route, thus poor hygienic practices promotes spread.Cryptosporidiumis not susceptible to disinfectants, including chlorine. Hence transmission via contamination of drinking water can occur unless specific precautions are taken.Cryptosporidiumspp. cause diarrhoea predominantly in children and in immunosupressed individuals. In fact, the greatest burden of disease is among children in developing countries where the parasite is implicated as a cause of persistent diarrhoea and malnutrition in children. The prevalence of this infection is likely underestimated due to limitations in diagnostic testing even in developed countries. Treatment with nitozoxanide achieves cure in children. However results are not less dramatic in individuals with depressed cellular immunity.
Stomata
Authors: Roelfsema M Rob G , Hedrich Rainer 
Published: March 2009

Abstract

Stomata are small adjustable pores on the surface of aerial plant tissues. The pores open to facilitate uptake of carbon dioxide and close to limit the loss of water. Consistent with this function, stomata open in the light to enable photosynthesis and close during drought. Stomatal movements are forced by changes in the volume of two guard cells that are positioned on either side of the pore. During stomatal opening, guard cells accumulate potassium salts, causing an osmotically driven uptake of water. Owing to the influx of water the guard cells swell and bend, thereby pushing each other apart and creating an open pore in the middle. Various environmental signals, such as light, carbon dioxide and humidity, influence the ion‐transport machinery within the guard cell and thus alter stomatal movement. Because of their role in regulating carbon dioxide uptake and transpiration of water, stomata are likely to play a key role in the adaption of plants to the anticipated global warming.

Key concepts

Stomata are small adjustable pores in the leave surface that enable gas exchange.

Open stomata enable the uptake of carbon dioxide for photosynthesis, while closure prevents excessive loss of water during drought.

During evolution, stomata enabled plants to survive in dry environments.

Cell‐to‐cell signalling controls the development of stomata in the leaf surface.

Stomatal movements are forced by two guard cells, surrounding the pore.

Guard cells cause stomata opening through osmotically driven swelling, based on the uptake of K
+
salts.

Environmental signals regulate ion transport in guard cells.

Guard cells sense light with blue light‐sensitive phototropins as well as through changes in the intercellular carbon dioxide concentration.

Drought acts on guard cells via release of the stress hormone abscisic acid.

Stomata are likely to play an important role in the adaption of plants to predicted global changes.
Müller, Johannes Peter (1801–1858)
Authors: Lohff Brigitte 
Published: March 2009

Abstract

In 1819, he started his medical studies at the University of Bonn in Germany. In 1826, he formulated the
Law of Specific Sense Energy
. With his anatomical and physiological research he became one of the most important scientists of life sciences in Europe. Since 1833 until his death, he was director of the Institute of Anatomy and Physiology at the University of Berlin. He mainly worked in the field of sensory, haematological, pathological anatomy and physiology as well as systematic zoology and marine biology. Müller's exceptional position in the history of medicine and zoology was not only connected with his own research, but was also due to his epistemological reflections on scientific physiology and experimental medicine and his role as an influential and important teacher.
Gene Expression in Yeast
Authors: Scheiner‐Bobis Georgios 
Published: March 2009

Abstract
In the past few decades expression of foreign genes in yeast has not only been a very powerful tool for analysing and understanding protein function within the framework of scientific investigations, it also has become a major economic factor of the biotechnological industries. The article presented here deals with well‐established methods and strategies for ensuing reliable transfer of foreign genes and sustained protein production in yeast.
Discrimination in Insurance: Experience in the United States
Authors: Hall Mark A 
Published: March 2009

Abstract
Health and life insurers may wish to discriminate based on genetic information by classifying people as high risk or unhealthy based on genetic tests that predict future health problems, rather than on diagnosis of current illness. In the USA, the fear of genetic discrimination by insurers is much greater than the reality, especially for health insurance. The economics of health insurance makes it unlikely that health insurers will want to consider purely predictive genetic information, and there are ample legal threats to keep this possibility from materializing, including the 2008 Genetic Information Nondiscrimination Act. Empirical studies consistently document the virtual absence of any genetic discrimination by health insurers. Life insurers are more likely to consider results from predictive genetic tests, but this practice currently is not widespread.
Craniofacial Defects and Cleft Lip and Palate
Authors: Thomason Helen A , Dixon Michael J 
Published: March 2009

Abstract
Craniofacial abnormalities are common and distressing birth defects which result from abnormalities of neural crest cell ontogeny and abnormal growth or fusion of the facial processes, palatal shelves or cranial sutures. These defects may result from mutations in a single gene or through a combination of genetic and environmental factors. The increasing availability of genetically modified mice that exhibit craniofacial abnormalities together with expression analyses has played, and will continue to play, an important role in identifying candidate genes for craniofacial abnormalities.
Environmental Stochasticity
Authors: Fujiwara Masami 
Published: March 2009

AbstractEnvironmental stochasticity is unpredictable spatiotemporal fluctuation in environmental conditions, and it is one of the main sources of fluctuation in ecological processes. The term is often used in the ecology and evolution literature. Unpredictability is defined as a lack of ability to predict the future state precisely so that only its distribution can be known. Environment is typically defined as any set of physical, chemical and biological conditions that organisms experience, such as temperature, nutrient availability and the abundance of predators. Environmental stochasticity influences how population abundance fluctuates and affects the fate (e.g. persistence or extinction) of populations. In an evolutionary time scale, environmental stochasticity also affects life history strategy of organisms. Incorporating environmental stochasticity into analysis requires some care. Stochastic equations sometimes do not have explicit solutions so that simulations are required, and statistical analysis must separate other confounding factors such as stochastic sampling errors and demographic stochasticity.Key ConceptsEnvironmental stochasticity is unpredictable spatiotemporal fluctuations in environmental conditions.Correlation between time‐lagged environmental states is one statistical measure of its predictability.Environmental stochasticity is reflected in the fluctuations in ecological processes and affects their fate (e.g. extinction or persistence of populations).Observed population dynamics consist of fluctuation due to environmental stochasticity, but it is often confounded with other factors such as sampling errors and demographic stochasticity.All of the fluctuations in ecological data are often erroneously attributed to environmental stochasticity alone.Evolutionary dynamics are also affected by environmental stochasticity.Autoregressive moving average (ARMA) models are an example of statistical models incorporating environmental stochasticity.Using stochastic differential and difference equation models, mechanistic ecological models incorporating environmental stochasticity can be built.
Spinal Cord: Repair and Rehabilitation
Authors: Reier Paul J , Lane Michael A , Behrman Andrea L , Howland Dena R 
Published: March 2009

Abstract
Functional deficits following spinal cord injury are no longer viewed as totally irreversible. Laboratory findings indicate the ability to walk can be partially restored by individual or combined therapeutic approaches targeting specific cellular responses to trauma. In addition, certain rehabilitation strategies can enhance ambulatory capacity, as well as stimulate certain intrinsic cellular or molecular repair processes. Other findings indicate the spinal cord is not as ‘hard‐wired’ as previously believed, and that neural circuitries in the injured spinal cord undergo natural remodelling with some changes appearing to facilitate some improvements in function over time. These collective observations highlight intriguing opportunities for achieving better functional outcomes and quality of life by interfacing cellular and molecular treatments with rehabilitation techniques that can amplify natural or therapeutically directed repair mechanisms. Whereas challenges remain, interactive training/exercise is becoming recognized as a fundamental adjunct to a growing list of potential therapeutic interventions for promoting spinal cord regeneration and neuroplasticity.
The Aetiologic Spectrum of Cerebellar Ataxia: Acquired Causes of Ataxia
Authors: Todd Peter K , Taylor J Paul 
Published: March 2009

Abstract

Ataxia is a common finding in patients seen in neurological practice and can be the result of a wide variety of causes. Although cerebellar degeneration can be chronic and slowly progressive, acute cerebellar swelling due to infarction, oedema or haemorrhage can have rapid and catastrophic effects and is a true neurological emergency. Here we set out to briefly describe the clinical/anatomical correlates of cerebellar disease and to provide a broad differential diagnosis for patients who present with cerebellar ataxia. This article specifically focuses on acquired causes of cerebellar ataxia. A separate complementary article discusses common hereditary causes of cerebellar ataxia.

Key Concepts

Clinical syndromes associated with cerebellar dysfunction may be divided into syndromes that predominantly affect the midline cerebellar structures (gait and ocular dysfunction predominant) or the cerebellar hemisphere(s) (ipsilateral appendicular ataxia, dysarthria).

Acute onset of cerebellar ataxia is most commonly associated with vascular disorders (stroke or haemorrhage), toxins or infectious aetiologies.

Subacute onset cerebellar ataxia can result from a variety of causes, including infectious, neoplastic, autoimmune and metabolic abnormalities. Many of these causes of ataxia are treatable.

Most slowly progressive cerebellar ataxias result from neurodegenerative aetiologies, either inherited or sporadic.
Heat opens axon initial segment sodium channels: A febrile seizure mechanism?
Authors: Thomas Evan A. , Hawkins Roger J. , Richards Kay L. , Xu Ruwei , Gazina Elena V. , Petrou Steven 
Published: March 2009

AbstractObjectiveA number of hypotheses have been put forward as to why humans respond to fever by seizing. The current leading hypotheses are that respiratory alkalosis produces an as yet unidentified change in neural excitability or that inflammatory mediators potentiate excitatory synaptic transmission. However, it is well known that ion channel gating rates increase with increased temperature. Furthermore, skeletal and cardiac sodium channel activation can be temperature sensitive in some situations. We measured the temperature sensitivity of the brain sodium channel, NaV1.2, to determine whether febrile temperatures might produce a direct increase in neuronal excitability.MethodsThe effect of temperature on NaV1.2 electrophysiological properties was measured in a transfected mammalian cell line. The subcellular location of NaV1.2 in the mouse brain was ascertained using antibodies against NaV1.2 and ankyrin‐G. Computer simulation of a hippocampal granule cell model was used to predict the effect of temperature on action potential firing.ResultsAs well as the expected increase in gating rates, the voltage dependence of activation became 7.6mV more negative when the temperature was increased from 37°C to 41°C. NaV1.2 was localized to the axon initial segment in hippocampal and cortical neurons. Computer simulation showed that increased gating rates and the more negative activation dramatically increase neuronal excitability.InterpretationThe direct effect of heat on ion channels localized to the site of action potential initiation potentially causes a profound increase in neuronal excitability. This is likely to contribute to febrile seizure genesis. Ann Neurol 2009;66:219–226
Autism and other neuropsychiatric symptoms are prevalent in individuals with MeCP2 duplication syndrome
Authors: Ramocki Melissa B. , Peters Sarika U. , Tavyev Y. Jane , Zhang Feng , Carvalho Claudia M. B. , Schaaf Christian P. , Richman Ronald , Fang Ping , Glaze Daniel G. , Lupski James R. , Zoghbi Huda Y. 
Published: March 2009

AbstractObjectiveThere have been no objective assessments to determine whether boys with MECP2 duplication have autism or whether female carriers manifest phenotypes. This study characterizes the clinical and neuropsychiatric phenotypes of affected boys and carrier females.MethodsEight families (9 males and 9 females) with MECP2 duplication participated. A detailed history, physical examination, electroencephalogram, developmental evaluation, Autism Diagnostic Observation Schedule, and Autism Diagnostic Interview–Revised were performed for each boy. Carrier females completed the Symptom Checklist‐90‐R, Wechsler Abbreviated Scale of Intelligence, Broad Autism Phenotype Questionnaire, and detailed medical and mental health histories. Size and gene content of each duplication were determined by array comparative genome hybridization. X‐chromosome inactivation patterns were analyzed using leukocyte DNA. MECP2 and IRAK1 RNA levels were quantified from lymphoblast cell lines, and western blots were performed to assess MeCP2 protein levels.ResultsAll of the boys demonstrated mental retardation and autism. Poor expressive language, gaze avoidance, repetitive behaviors, anxiety, and atypical socialization were prevalent. Female carriers had psychiatric symptoms, including generalized anxiety, depression, and compulsions that preceded the birth of their children. The majority exhibited features of the broad autism phenotype and had higher nonverbal compared to verbal reasoning skills.InterpretationAutism is a defining feature of the MECP2 duplication syndrome in boys. Females manifest phenotypes despite 100% skewing of X‐inactivation and normal MECP2 RNA levels in peripheral blood. Analysis of the duplication size, MECP2 and IRAK1 RNA levels, and MeCP2 protein levels revealed that most of the traits in affected boys are likely due to the genomic region spanning of MECP2 and IRAK1. The phenotypes observed in carrier females may be secondary to tissue‐specific dosage alterations and require further study. Ann Neurol 2009;66:771–782
Relative Orientation of Rigid Nitroxides by PELDOR: Beyond Distance Measurements in Nucleic Acids
Authors: Schiemann Olav , Cekan Pavol , Margraf Dominik , Prisner Thomas F. , Sigurdsson Snorri Th. 
Published: March 2009

AbstractEine starre Spinmarkierung Çermöglichte es, den Abstand und die Orientierung zweier Nitroxid‐Spinmarkierungen in DNA mithilfe von PELDOR bei üblichen X‐Band‐Frequenzen zu bestimmen. Die Information über die Orientierung erhielt man, indem die Position der Detektionspulse im Nitroxidspektrum variiert wurde. Eine Simulation des Satzes von Zeitspuren ergab sehr genaue Werte für Abstände und Winkel.magnified image
Sulfatierte und nicht sulfatierte Glycopeptid‐Erkennungsdomänen des P‐Selektin‐Glycoprotein‐Liganden 1 und ihre Bindung an P‐ und E‐Selektin
Authors: Baumann Katharina , Kowalczyk Danuta , Gutjahr Tobias , Pieczyk Markus , Jones Claire , Wild Martin K. , Vestweber Dietmar , Kunz Horst 
Published: March 2009

AbstractTotalsynthese via Blockglycosylierung und selektive chemische O‐Sulfatierung von Tyrosinresten ergaben die Glycopeptid‐Erkennungsregion A (X=SO3−) des P‐Selektin‐Glycoprotein‐Liganden 1, in dem die terminale Sialinsäure der komplexen Hexasaccharid‐Seitenkette durch (S)‐Cyclohexylmilchsäure als Mimetikum ersetzt ist. In Bindungsassays zeigt die O‐sulfatierte Form A hohe Affinität zu P‐Selektin, die nicht sulfatierte Form zu E‐Selektin.magnified image
A Different Approach to Enantioselective Organic Synthesis: Absolute Asymmetric Synthesis of Organometallic Reagents
Authors: Lennartson Anders , Olsson Susanne , Sundberg Jonas , Håkansson Mikael 
Published: March 2009

AbstractVoilà, optisch aktiv: Beide Enantiomere von 1‐Chlorinden wurden ausgehend von durchweg achiralen Ausgangsmaterialien und ohne die Verwendung optisch aktiver Katalysatoren mit hoher Selektivität synthetisiert (siehe Schema). NCS=N‐Chlorsuccinimid.magnified image
Formation of Ammonia from an Iron Nitrido Complex
Authors: Scepaniak Jeremiah J. , Young Jessica A. , Bontchev Ranko P. , Smith Jeremy M. 
Published: March 2009

AbstractRadikaler Eingriff: Die Reaktion des Eisen(IV)‐Nitrid‐Komplexes [PhB(MesIm)3FeN] (siehe Bild, Mes=2,4,6‐Me3C6H2) mit 1‐Hydroxy‐2,2,6,6‐tetramethylpiperidin (TEMPO‐H) führte quantitativ zu [PhB(MesIm)3Fe(tempo)] sowie zu hohen Ausbeuten an Ammoniak. Der Mechanismus dieses Prozesses umfasst wahrscheinlich die Übertragung eines Wasserstoffatoms von TEMPO‐H auf den Nitridkomplex. Eine analoge Reaktion mit dem Triphenylmethylradikal ergab [PhB(MesIm)3FeNCPh3].magnified image
One‐Pot Formation of Large Macrocycles with Modifiable Peripheries and Internal Cavities
Authors: Ferguson Joseph S. , Yamato Kazuhiro , Liu Rui , He Lan , Zeng Xiao Cheng , Gong Bing 
Published: March 2009

AbstractAromatische Oligohydrazid‐Makrocyclen, deren Rückgrat durch Dreizentren‐Wasserstoffbrücken in eine planare Anordnung gezwungen wird, entstehen in hohen Ausbeuten aus monomeren Disäurechloriden und Dihydraziden. Für Makrocyclen mit insgesamt sechs meta‐verknüpften Pyridin‐ und Benzolringen beträgt der Innendurchmesser ca. 10 Å. In größeren Spezies mit alternierend meta‐ und para‐verknüpften Benzolringen ragen einige Substituenten ins Ringinnere (siehe Bild).magnified image
Stereodivergent De Novo Synthesis of Branched Amino Sugars by Lewis Acid Promoted Rearrangement of 1,2‐Oxazines
Authors: Pfrengle Fabian , Lentz Dieter , Reißig Hans‐Ulrich 
Published: March 2009

AbstractWell concealed: 1,2‐oxazines such as 1 rearrange under Lewis acidic conditions to bicyclic products of type 2, which can be incorporated into oligosaccharides as protected amino sugar equivalents. Subsequent reductive steps provide unusual oligosaccharides 3 having C2‐branched 4‐amino sugar units. Most of the reactions proceed with excellent stereocontrol and allow the synthesis of a collection of stereoisomers.magnified image
Sulfated and Non‐Sulfated Glycopeptide Recognition Domains of P‐Selectin Glycoprotein Ligand 1 and their Binding to P‐ and E‐Selectin
Authors: Baumann Katharina , Kowalczyk Danuta , Gutjahr Tobias , Pieczyk Markus , Jones Claire , Wild Martin K. , Vestweber Dietmar , Kunz Horst 
Published: March 2009

AbstractTotal synthesis through block glycosylation and selective chemical O‐sulfation of tyrosine residues yielded the glycopeptide recognition domain A (X=SO3−) of the P‐selectin glycoprotein ligand 1, in which the terminal sialic acid of the complex hexasaccharide side chain was replaced by (S)‐cyclohexyl lactic acid. In binding assays the O‐sulfated structure A showed high affinity towards P‐selectin, the non‐sulfated towards E‐selectin.magnified image
A Different Approach to Enantioselective Organic Synthesis: Absolute Asymmetric Synthesis of Organometallic Reagents
Authors: Lennartson Anders , Olsson Susanne , Sundberg Jonas , Håkansson Mikael 
Published: March 2009

AbstractVoilà, optical activity: Both enantiomers of 1‐chloroindene have been synthesized in high selectivity from solely achiral starting materials, and without using optically active catalysts (see scheme). These symmetry‐breaking syntheses provide a proof‐of‐concept for a new approach to asymmetric synthesis. NCS=N‐chlorosuccinimide.magnified image
Splendid Isolation for a Nonmetallic Dication
Authors: Müller Thomas 
Published: March 2009

AbstractConfined, but happy: The triflate salt of a germanium(II) dication, an atomic cation of a nonmetal, was isolated by encapsulation in [2.2.2]cryptand (see formula and molecular structure in the crystal). The cryptand satisfies the electron demand of the cation and sterically protects it (see space‐filling depiction, right).magnified image
High Electrical Conductance of Single Molecules: A Challenge in the Series of Conjugated Oligomers
Authors: Meier Herbert 
Published: March 2009

AbstractEn route to molecular electronics: As extended, conjugated oligomers are desirable for molecular electronics, their electrical conductance should display a low attenuation factor. Zinc‐complexed oligo(ethynyleneporphyrindiylethynylene)s have been prepared that are distinguished by ultralow attenuation factors in single‐molecule conductance.magnified image
Hazardous air pollutants emission from coal and oil‐fired power plants
Authors: Pudasainee Deepak , Kim Jeong‐Hun , Lee Sang‐Hyeob , Park Ju‐Myon , Jang Ha‐Na , Song Geum‐Ju , Seo Yong‐Chil 
Published: March 2009

AbstractHazardous air pollutants (HAPs) emission characteristics from coal (anthracite, bituminous) and oil‐fired power plants were studied in order to control pollutants by formulating US maximum achievable control technology (MACT)‐like regulation in Korea. Sampling and analysis were carried out according to either Korean standard test method or US EPA method. Relatively lower levels of NOx and SOx were emitted from plants burning bituminous than the anthracite coal. Less dust was emitted from oil‐fired power plants. Mercury, lead, and chromium were dominant in coal‐fired power plants, following which, nickel and chromium were emitted from oil‐fired power plants. The major volatile organic compounds (VOCs) emitted from coal‐fired plants were 1,2‐dichloroethane, benzene, carbon tetrachloride, chloroform, trichloro‐ethylene. The emission of mercury and other heavy metals in flue gas was attributed to fuel types, operating conditions, residence time in the control devices and air pollution control devices configuration. After emission tests in the field and on analysis of the continuous emission monitoring data collected from facilities under operation and consideration of other various factors, management guidelines will be suggested with special reference to US MACT‐like regulation. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.