bluuebunny/crossref_metadata_2025 huggingface dataset:
Replication of DNA during barley endosperm development
Authors: Giese Henriette
Published: October 2007

The incorporation of [6-3H]-thymidine into DNA of developing barley endosperm was examined by autoradiography of cross sections of seeds and DNA analysis. The majority of nuclear divisions took place in the very young endosperm, but as late as 25 days after anthesis there was evidence for DNA replication. The DNA content of the endosperm increases during development and in response to nitrogen application in parallel to the storage protein synthesis profile. The hordein genes were hypersensitive to DNase I treatment throughout development. Key words: DNase I sensitivity, N nutrition, pulse labelling, spike culture.
Inheritance of isozyme production and sexual reproduction in Phytophthora infestans
Authors: Chang T. T. , Ko W. H.
Published: October 2007

Analysis of the isozyme patterns of glucosephosphate isomerase and peptidase from selfed progeny of isolates of Phytophthora infestans showed that some gave only a single slow or fast band, whereas others gave three bands, i.e., a slow, a fast, and an intermediate band. These results are consistent with the hypothesis that each locus is controlled by a single codominant gene. The single-banded pattern, either slow or fast, is due to homozygosity of one or the other allele, while the three-banded pattern is due to heterozygosity. The results also show that the genes for glucosephosphate isomerase and peptidase are not linked. Progeny from direct pairings between isolates with different homozygous genotypes for isozyme patterns consisted of selfs of both parents and hybrids, self of one parent and hybrids, and hybrids only. Key words: Phytophthora infestans, genetics, isozyme pattern.
Electron microscopy of two trichomycetous fungi attached to the hindgut lining of pill bugs
Authors: Saikawa Masatoshi , Sugiura Kaori , Sato Hiroki
Published: October 2007

Two species of trichomycetous fungi, Asellaria armadillidii (Asellariales) and Parataeniella armadillidii (Eccrinales), were found attached to the hindgut lining of the pill bug, Armadillidium vulgare. In the former fungus, the thallus was composed of a basal cell bearing an apical whorl of many lateral branches. Electron micrographs in ultrathin sections showed that an electron-opaque holdfast substance surrounded the rhizoidal projections of the basal cell. The cross wall of the thallus was the typical bifurcate type of septum, i.e., the wall flared at the central perforation which was occluded by an electron-opaque plug. This is the third report of this type of septum in the order Asellariales. The bifurcated structure of the septal wall was found to remain at the distal portion of the mature arthrospore cell wall. In P. armadillidii, both primary and secondary infestation sporangiospores were examined in ultrathin sections. A number of electron-transparent pits, 40–50 nm in diameter, were found in the basal portion of the cell wall of secondary infestation sporangiospores which were still contained inside the sporangium. Key words: Asellaria, bifurcate septum, Parataeniella, Trichomycetes.
Biodiversity among Festuca (Poaceae) in North America: diagnostic evidence from DELTA and clustering programs, and an INTKEY package for interactive, illustrated identification and information retrieval
Authors: Aiken Susan G. , McJannet Cheryl L. , Consaul Laurie L. , Dallwitz Michael J.
Published: October 2007

Biodiversity among taxa of Festuca occurring in North America has been investigated from a revised and illustrated database developed using the DELTA software package. The database includes common names; the place of valid publication of the name; the location of type specimens, when known, and whether we have examined them; synonymy; data on morphology, anatomy, and chromosome number(s); habitat and distribution information; subgeneric classification; taxonomic notes; and more than 200 images. The data are available on the Internet via the World Wide Web (WWW) at http://www.keil.ukans.edu/delta/or by anonymous file transfer protocol (ftp) from ftp.keil.ukans.edu, as natural-language descriptions and as an INTKEY interactive identification and information-retrieval package for MS-Windows. INTKEY and other DELTA programs have been used to assess biodiversity and have supported recognition of several species that have often been placed into synonymy (e.g., Festuca calligera and Festuca earlei), a status change for Festuca idahoensis subsp. roemeri comb.nov., placing Festuca brachyphylla subsp. breviculmis into synonymy with F. brachyphylla subsp. coloradensis, and suggested a taxonomy that is presented in an annotated list. Phenetic and cladistic analyses suggest that the traditional generic limits of Festuca and Lolium should be retained and four subgenera recognized within Festuca, subgg. Festuca, Leucopoa, Schedonorus, and Subulatae, with sects. Subulatae and Obtusae. Key words: DELTA, Festuca, Lolium, Poaceae, biodiversity, WWW, taxonomy.
THE STABILIZED POINCARE–HEISENBERG ALGEBRA: A CLIFFORD ALGEBRA VIEWPOINT
Authors: GRESNIGT N. G. , RENAUD P. F. , BUTLER P. H.
Published: October 2007

The stabilized Poincare–Heisenberg algebra (SPHA) is a Lie algebra of quantum relativistic kinematics generated by fifteen generators. It is obtained from imposing stability conditions after combining the Lie algebras of quantum mechanics and relativity. In this paper, we show how the sixteen-dimensional real Clifford algebras Cℓ(1,3) and Cℓ(3,1) can both be used to generate the SPHA. The Clifford algebra path to the SPHA avoids the traditional stability considerations. It is conceptually easier and more straightforward to work with a Clifford algebra. The Clifford algebra path suggests that the next evolutionary step toward a theory of physics at the interface of GR and QM might be to depart from working in spacetime and instead to work in spacetime–momentum.
THE IMPORTANCE OF THE "MAGNETIC" COMPONENTS OF GRAVITATIONAL WAVES IN THE RESPONSE FUNCTIONS OF INTERFEROMETERS
Authors: CORDA CHRISTIAN
Published: October 2007

With an enlighting analysis, Baskaran and Grishchuk have recently shown the presence and importance of the so-called "magnetic" components of gravitational waves (GWs), which have to be taken into account in the context of the total response functions of interferometers for GWs propagating from arbitrary directions. In this paper, more detailed angular and frequency dependences of the response functions for the magnetic components are given in the approximation of wavelength much larger than the linear dimensions of the interferometer, with a specific application to the parameters of the LIGO and Virgo interferometers. The results of this paper agree with the work of Baskaran and Grishchuk, in which it has been shown that the identification of "electric" and "magnetic" contributions is unambiguous in the long-wavelength approximation. At the end of this paper, the angular and frequency dependences of the total response functions of the LIGO and Virgo interferometers are given. In the high-frequency regime, the division on "electric" and "magnetic" components becomes ambiguous, thus the full theory of gravitational waves has to be used. Our results are consistent with the ones of Baskaran and Grishchuk for this case.
Thyroid hormone (T3) rapidly activates p38 and AMPK in skeletal muscle in vivo
Authors: Irrcher Isabella , Walkinshaw Donald R. , Sheehan Treacey E. , Hood David A.
Published: October 2007

Thyroid hormone (T3) regulates the function of many tissues within the body. The effects of T3 have largely been attributed to the modulation of thyroid hormone receptor-dependent gene transcription. However, nongenomic actions of T3 via the initiation of signaling events are emerging in a number of cell types. This study investigated the ability of short-term T3 treatment to phosphorylate and, therefore, activate signaling proteins in rat tissues in vivo. The kinases investigated included p38, AMP-activated protein kinase (AMPK), and extracellular signal-regulated kinase (ERK) 1/2. Following 2 h of T3 treatment, p38 and AMPK phosphorylation was increased in both the slow-twitch soleus and the fast-twitch plantaris muscles. In contrast, ERK1/2 was not activated in either muscle type. Neither p38 nor AMPK was affected in heart. However, AMPK activation was decreased by T3 in liver. ERK1/2 activation was decreased by T3 in heart, but increased in liver. Possible downstream consequences of T3-induced kinase phosphorylation were investigated by measuring cAMP response element binding protein (CREB) and thyroid hormone receptor DNA binding, as well as peroxisome proliferator-activated receptor-α coactivator-1 mRNA levels. Protein DNA binding to the cAMP or thyroid hormone response elements was unaltered by T3. However, peroxisome proliferator-activated receptor-α coactivator-1 mRNA expression was increased following 12 h of T3 treatment in soleus. These data are the first to characterize the effects of T3 treatment on kinase phosphorylation in vivo. We show that T3 rapidly modifies kinase activity in a tissue-specific fashion. Moreover, the T3-induced phosphorylation of p38 and AMPK in both slow- and fast-twitch skeletal muscles suggests that these events may be important in mediating hormone-induced increases in mitochondrial biogenesis in skeletal muscle.
Cerebral blood flow and metabolism during exercise: implications for fatigue
Authors: Secher Neils H. , Seifert Thomas , Van Lieshout Johannes J.
Published: October 2007

During exercise: the Kety-Schmidt-determined cerebral blood flow (CBF) does not change because the jugular vein is collapsed in the upright position. In contrast, when CBF is evaluated by 133Xe clearance, by flow in the internal carotid artery, or by flow velocity in basal cerebral arteries, a ∼25% increase is detected with a parallel increase in metabolism. During activation, an increase in cerebral O2 supply is required because there is no capillary recruitment within the brain and increased metabolism becomes dependent on an enhanced gradient for oxygen diffusion. During maximal whole body exercise, however, cerebral oxygenation decreases because of eventual arterial desaturation and marked hyperventilation-related hypocapnia of consequence for CBF. Reduced cerebral oxygenation affects recruitment of motor units, and supplemental O2 enhances cerebral oxygenation and work capacity without effects on muscle oxygenation. Also, the work of breathing and the increasing temperature of the brain during exercise are of importance for the development of so-called central fatigue. During prolonged exercise, the perceived exertion is related to accumulation of ammonia in the brain, and data support the theory that glycogen depletion in astrocytes limits the ability of the brain to accelerate its metabolism during activation. The release of interleukin-6 from the brain when exercise is prolonged may represent a signaling pathway in matching the metabolic response of the brain. Preliminary data suggest a coupling between the circulatory and metabolic perturbations in the brain during strenuous exercise and the ability of the brain to access slow-twitch muscle fiber populations.
Chip Thickness and Microhardness Prediction Models during Turning of Medium Carbon Steel
Authors: Alrabii S. A. , Zumot L. Y.
Published: October 2007

Cutting tests were conducted to medium carbon steel using HSS tools with cutting fluid. The experimental design used was based on response surface methodology (RSM) using a central composite design. Chips were collected at different machining conditions and thickness and microhardness measurements taken and analyzed using “DESIGN EXPERT 7” experimental design software. Mathematical models of the responses (thickness and microhardness) as functions of the conditions (speed, feed, and depth of cut) were obtained and studied. The resultant second-order models show chip thickness increases when increasing feed and speed, while increasing depth of cut resulted in a little effect on chip thickness. Chip microhardness increases with increasing depth of cut. It also increases with increasing speed and feed up to a certain level beyond which further increases cause a drop in microhardness.
Role of the Peroxisome Proliferator‐Activated Receptors, Adenosine Monophosphate‐Activated Kinase, and Adiponectin in the Ovary
Authors: Dupont Joëlle , Chabrolle Christine , Ramé Christelle , Tosca Lucie , Coyral-Castel Stéphanie
Published: October 2007

The mechanisms controlling the interaction between energy balance and reproduction are the subject of intensive investigations. The integrated control of these systems is probably a multifaceted phenomenon involving an array of signals governing energy homeostasis, metabolism, and fertility. Two fuel sensors, PPARs, a superfamily of nuclear receptors and the kinase AMPK, integrate energy control and lipid and glucose homeostasis. Adiponectin,
one of the adipocyte‐derived factors mediate its actions through the AMPK or PPARs pathway. These three molecules are expressed in the ovary, raising questions about the biological actions of fuel sensors in fertility and the use of these molecules to treat fertility problems. This review will highlight the expression and putative role of PPARs, AMPK, and adiponectin in the ovary, particularly during folliculogenesis, steroidogenesis, and oocyte maturation.
Intimate Partner Violence and Suicidality in Low-Income African American Women
Authors: Reviere Susan L. , Farber Eugene W. , Twomey Heather , Okun Alexandra , Jackson Emily , Zanville Holly , Kaslow Nadine J.
Published: October 2007

This study used quantitative and qualitative methods to examine psychological factors that influence links between intimate partner violence (IPV) and suicidality in a sample of low-income African American women. Quantitative results demonstrated greater general coping, more efficacious behavioral strategies in response to IPV, more effective use of resources, greater use of social support, and less substance use among women who did not attempt suicide compared with those who did. Qualitative findings showed that suicide attempters showed less adaptive coping strategies aimed at accommodating the abuser, whereas nonattempters were more focused on strategies that supported leaving the relationship and/or avoiding further harm.
Race/Ethnicity, Religious Involvement, and Domestic Violence
Authors: Ellison Christopher G. , Trinitapoli Jenny A. , Anderson Kristin L. , Johnson Byron R.
Published: October 2007

The authors explored the relationship between religious involvement and intimate partner violence by analyzing data from the first wave of the National Survey of Families and Households. They found that: (a) religious involvement is correlated with reduced levels of domestic violence; (b) levels of domestic violence vary by race/ethnicity; (c) the effects of religious involvement on domestic violence vary by race/ethnicity; and (d) religious involvement, specifically church attendance, protects against domestic violence, and this protective effect is stronger for African American men and women and for Hispanic men, groups that, for a variety of reasons, experience elevated risk for this type of violence.
Abusers' Perceptions of the Effect of Their Intimate Partner Violence on Children
Authors: Rothman Emily F. , Mandel David G. , Silverman Jay G.
Published: October 2007

Little is known about how intimate partner violence (IPV) abusers perceive the effect of their violence on their children. Analyzing the attitudes and behavioral intentions of 464 partner-abusive fathers, biological fathers were found to be more likely than social fathers to express concern about the effects of their abuse on their children. However, biological fathers were no more likely than social fathers to report intentions to stop their violence or otherwise take action to mitigate the harm of IPV exposure to their children. The findings suggest that fathers' statements of concern may be poor indicators of their intentions to refrain from abusive behavior.
A study on the two binding sites of hexokinase on brain mitochondria
Authors: Golestani Abolfazl , Ramshini Hassan , Nemat-Gorgani Mohsen
Published: October 2007

Background

Type I hexokinase (HK-I) constitutes the predominant form of the enzyme in the brain, a major portion of which is associated with the outer mitochondrial membrane involving two sets of binding sites. In addition to the glucose-6-phosphate (G6P)-sensitive site (Type A), the enzyme is bound on a second set of sites (Type B) which are, while insensitive to G6P, totally releasable by use of high concentrations of chaotropic salts such as KSCN. Results obtained on release of HK-I from these "sites" suggested the possibility for the existence of distinct populations of the bound enzyme, differing in susceptibility to release by G6P.

Results

In the present study, the sensitivity of HK-I toward release by G6P (2 mM) and a low concentration of KSCN (45 mM) was investigated using rat brain, bovine brain and human brain mitochondria. Partial release from the G6P-insensitive site occurred without disruption of the mitochondrial membrane as a whole and as related to HK-I binding to the G6P-sensitive site. While, as expected, the sequential regime release-rebinding-release was observed on site A, no rebinding was detectable on site B, pre-treated with 45 mM KSCN. Also, no binding was detectable on mitochondria upon blocking site A for HK-I binding utilizing dicyclohexylcarbodiimide (DCCD), followed by subsequent treatment with KSCN. These observations while confirmed the previously-published results on the overall properties of the two sites, demonstrated for the first time that the reversible association of the enzyme on mitochondria is uniquely related to the Type A site.

Conclusion

Use of very low concentrations of KSCN at about 10% of the level previously reported to cause total release of HK-I from the G6P- insensitive site, caused partial release from this site in a reproducible manner. In contrast to site A, no rebinding of the enzyme takes place on site B, suggesting that site A is 'the only physiologically-important site in relation to the release-rebinding of the enzyme which occur in response to the energy requirements of the brain. Based on the results presented, a possible physiological role for distribution of the enzyme between the two sites on the mitochondrion is proposed.
Parvovirus B19 infection in Tunisian patients with sickle-cell anemia and acute erythroblastopenia
Authors: Regaya Faouzi , Oussaief Lassad , Bejaoui Mohamed , Karoui Mongi , Zili Mohamed , Khelifa Ridha
Published: October 2007

Background

Human parvovirus B19 is the etiologic agent of erythema infectiosum in children. It is also associated with other clinical manifestations in different target groups. Patients with chronic hemolytic anemia are at high risk of developing acute erythroblastopenia following infection by the virus. They usually become highly viremic and pose an increased risk of virus transmission. Close monitoring of such high risk groups is required for epidemiologic surveillance and disease prevention activities. Here we report a molecular epidemiological study on B19 virus infection in Tunisian patients with chronic hemolytic anemia.

Methods

This study was conducted on 92 young chronic hemolytic anemia patients who attended the same ward at the National Bone Marrow Transplantation Center of Tunis and 46 controls from a different hospital. Screening for IgM and IgG anti-B19 antibodies was performed using commercially available enzyme immunoassays and B19 DNA was detected by nested PCR in the overlapping VP1/VP2 region. DNA was sequenced using dideoxy-terminator cycle sequencing technology.

Results

Anti-parvovirus B19 IgG antibodies were detected in 26 of 46 sickle-cell anemia patients, 18 of 46 β-thalassemia and 7 of 46 controls. Anti-parvovirus B19 IgM antibodies were detected only in 4 of the sickle-cell anemia patients: two siblings and two unrelated who presented with acute erythroblastopenia at the time of blood collection for this study and had no history of past transfusion. B19 DNA was detected only in sera of these four patients and the corresponding 288 bp nested DNA amplicons were sequenced. The sequences obtained were all identical and phylogenetic analysis showed that they belonged to a new B19 virus strain of Genotype1.

Conclusion

A new parvovirus B19 strain of genotype1 was detected in four Tunisian patients with sickle-cell anemia. Virus transmission appeared to be nosocomial and resulted in acute erythroblastopenia in the four patients. The possibility of independent transmission of this B19 variant to the patients is unlikely in light of the present epidemiological data. However this possibility cannot be ruled out because of the low genetic variability of the virus.
Webtag: a new web tool providing tags/anchors for RT-PCR experiments with prokaryotes
Authors: Pinto Fernando Lopes , Svensson Håkan , Lindblad Peter
Published: October 2007

Background

Webtag is a tool providing oligonucleotide sequences (usually called tags or anchors) that are absent from a specified genome. These tags/anchors can be appended to gene specific primers for reverse transcriptase polymerase chain reaction experiments, circumventing genomic DNA contamination.

Results

The use of a relational database, in conjunction with a series of scripts written in PHP and Perl, allows the user to rapidly obtain tags that are: 1) suitable for a specific organism, and 2) compatible with other oligonucleotides to be used in the experimental procedures.

Conclusion

This new web tool allows scientists to easily and rapidly obtain suitable tags for RT-PCR experiments, and is available at http://www.egs.uu.se/software/webtag/.
Structure of Arabidopsis thaliana 5-methylthioribose kinase reveals a more occluded active site than its bacterial homolog
Authors: Ku Shao-Yang , Cornell Kenneth A , Howell P Lynne
Published: October 2007

Background

Metabolic variations exist between the methionine salvage pathway of humans and a number of plants and microbial pathogens. 5-Methylthioribose (MTR) kinase is a key enzyme required for methionine salvage in plants and many bacteria. The absence of a mammalian homolog suggests that MTR kinase is a good target for the design of specific herbicides or antibiotics.

Results

The structure of Arabidopsis thaliana MTR kinase co-crystallized with ATPγS and MTR has been determined at 1.9 Å resolution. The structure is similar to B. subtilis MTR kinase and has the same protein kinase fold observed in other evolutionarily related protein kinase-like phosphotransferases. The active site is comparable between the two enzymes with the DXE-motif coordinating the nucleotide-Mg, the D238 of the HGD catalytic loop polarizing the MTR O1 oxygen, and the RR-motif interacting with the substrate MTR. Unlike its bacterial homolog, however, the Gly-rich loop (G-loop) of A. thaliana MTR kinase has an extended conformation, which shields most of the active site from solvent, a feature that resembles eukaryotic protein kinases more than the bacterial enzyme. The G- and W-loops of A. thaliana and B. subtilis MTR kinase adopt different conformations despite high sequence similarity. The ATPγS analog was hydrolyzed during the co-crystallization procedure, resulting in ADP in the active site. This suggests that the A. thaliana enzyme, like its bacterial homolog, may have significant ATPase activity in the absence of MTR.

Conclusion

The structure of A. thaliana MTR kinase provides a template for structure-based design of agrochemicals, particularly herbicides whose effectiveness could be regulated by nutrient levels. Features of the MTR binding site offer an opportunity for a simple organic salt of an MTR analog to specifically inhibit MTR kinase.
The risk for bloodstream infections is associated with increased parenteral caloric intake in patients receiving parenteral nutrition
Authors: Dissanaike Sharmila , Shelton Marilyn , Warner Keir , O'Keefe Grant E
Published: October 2007

Background

Patients receiving total parenteral nutrition (TPN) are at high risk for bloodstream infections (BSI). The notion that intravenous calories and glucose lead to hyperglycemia, which in turn contributes to BSI risk, is widely held but is unproven. We therefore sought to determine the role that hyperglycemia and parenteral calories play in the development of BSI in hospitalized patients receiving TPN.

Methods

Two hundred consecutive patients initiated on TPN between June 2004 and August 2005 were prospectively studied. Information was collected on patient age, sex, admission diagnosis, baseline laboratory values, intensive care unit (ICU) status and indication for TPN. Patients in the ICU were managed with strict glycemic control, whereas control on the general ward was more liberal. The maximum blood glucose level over each 8-hour period was recorded, as were parenteral daily intake, enteral daily intake and total daily caloric intake. The primary outcome measure was the incidence of BSI. Additional endpoints were ICU length of stay, hospital length of stay and mortality.

Results

A total of 78 patients (39%) developed at least one BSI, which were more common in ICU patients than in other hospitalized patients (60/122 patients versus 18/78 patients; P < 0.001). Maximum daily blood glucose concentrations were similar in patients with BSI and in patients without BSI (197 mg/dl versus 196 mg/dl, respectively). Patients with BSI received more calories parenterally than patients without BSI (36 kcal/kg/day versus 31 kcal/kg/day, P = 0.003). Increased maximum parenteral calories, increased average parenteral calories, and treatment in the ICU were strong risk factors for developing BSI. There was no difference in mortality between patients with and without BSI.

Conclusion

Increased parenteral caloric intake is an independent risk factor for BSI in patients receiving TPN. This association appears unrelated to hyperglycemia. Based upon our observations, we suggest that parenteral caloric intake be prescribed and adjusted judiciously with care taken to account for all intravenous caloric sources and to avoid even short periods of increased intake.
3′, 5′-Cyclic Adenosine 5′-Monophosphate Response Element-Dependent Transcriptional Regulation of the Secretogranin II Gene Promoter Depends on Gonadotropin-Releasing Hormone-Induced Mitogen-Activated Protein Kinase Activation and the Transactivator Activating Transcription Factor 3
Authors: Xie Jianjun , Roberson Mark S.
Published: October 2007

Previous studies demonstrated that GnRH-induced secretogranin II (SgII) promoter regulation required a consensus cAMP response element (CRE) and protein kinase A/CRE binding protein. The present studies examined the role of additional components of the GnRH signaling network on SgII promoter activity with particular attention devoted to CRE-dependent gene regulation. Disruption of the SgII CRE by mutagenesis resulted in inhibition of GnRH agonist (GnRHa) induction of this promoter in αT3-1 cells. Pharmacological and dominant-negative inhibition of the ERK and c-Jun N-terminal kinase (JNK) signaling pathways revealed that GnRHa-induced SgII promoter activity required functional JNK and ERK modules. Combined inhibition of both pathways nearly abolished GnRHa-induced SgII promoter activity. Specific induction of the ERK cascade alone using overexpression of Raf-CAAX was not sufficient to activate the SgII gene promoter. In contrast, overexpression of the catalytic domain of the more pleiotropic MAPK activator, MAPK/ERK kinase-1, was sufficient to induce SgII promoter activity. The effect(s) of mitogen-activated protein/ERK kinase-1 on SgII promoter activity was CRE dependent and was reversed by the combined pharmacological inhibition of both JNK and ERK modules. CRE DNA binding studies demonstrated the recruitment of activating transcription factor (ATF)-3 and c-Jun to the CRE after administration of GnRHa to αT3-1 cells. Specific small interfering RNA knockdown of ATF3 reduced ATF3 DNA binding and the effect of GnRHa on the SgII promoter. These studies support the conclusion that MAPK signaling and ATF3 action are essential for full SgII promoter activation by GnRHa through a canonical CRE. Moreover, we suggest that within the GnRH signaling network, CRE-dependent gene regulation in general may be mediated primarily through the immediate early response gene ATF3.
Insight into the Neuroendocrine Site and Cellular Mechanism by which Cortisol Suppresses Pituitary Responsiveness to Gonadotropin-Releasing Hormone
Authors: Breen Kellie M. , Davis Tracy L. , Doro Lisa C. , Nett Terry M. , Oakley Amy E. , Padmanabhan Vasantha , Rispoli Louisa A. , Wagenmaker Elizabeth R. , Karsch Fred J.
Published: October 2007

Stress-like elevations in plasma glucocorticoids rapidly inhibit pulsatile LH secretion in ovariectomized sheep by reducing pituitary responsiveness to GnRH. This effect can be blocked by a nonspecific antagonist of the type II glucocorticoid receptor (GR) RU486. A series of experiments was conducted to strengthen the evidence for a mediatory role of the type II GR and to investigate the neuroendocrine site and cellular mechanism underlying this inhibitory effect of cortisol. First, we demonstrated that a specific agonist of the type II GR, dexamethasone, mimics the suppressive action of cortisol on pituitary responsiveness to GnRH pulses in ovariectomized ewes. This effect, which became evident within 30 min, documents mediation via the type II GR. We next determined that exposure of cultured ovine pituitary cells to cortisol reduced the LH response to pulse-like delivery of GnRH by 50% within 30 min, indicating a pituitary site of action. Finally, we tested the hypothesis that suppression of pituitary responsiveness to GnRH in ovariectomized ewes is due to reduced tissue concentrations of GnRH receptor. Although cortisol blunted the amplitude of GnRH-induced LH pulses within 1–2 h, the amount of GnRH receptor mRNA or protein was not affected over this time frame. Collectively, these observations provide evidence that cortisol acts via the type II GR within the pituitary gland to elicit a rapid decrease in responsiveness to GnRH, independent of changes in expression of the GnRH receptor.
Gonadal Steroid Hormones Maintain the Stress-Induced Acetylcholine Release in the Hippocampus: Simultaneous Measurements of the Extracellular Acetylcholine and Serum Corticosterone Levels in the Same Subjects
Authors: Mitsushima Dai , Takase Kenkichi , Funabashi Toshiya , Kimura Fukuko
Published: October 2007

To examine the role of gonadal steroid hormones in the stress responses of acetylcholine (ACh) levels in the hippocampus and serum corticosterone levels, we observed these parameters simultaneously in intact, gonadectomized, or gonadectomized steroid-primed rats. In both sexes of rats, neither gonadectomy nor the replacement of gonadal steroid hormone affected the baseline levels of ACh. However, gonadectomy severely attenuated the stress response of ACh, whereas the replacement of corresponding gonadal hormone successfully restored the response to intact levels. The gonadal hormones affected the serum corticosterone levels in a different manner; the testosterone replacement in orchidectomized rats suppressed the baseline and the stress response of corticosterone levels, whereas the 17β-estradiol replacement in ovariectomized rats increased the levels. We further found that letrozole or flutamide administration in intact male rats attenuated the stress response of ACh. In addition, flutamide treatment increased the baseline levels of corticosterone, whereas letrozole treatment attenuated the stress response of corticosterone. Moreover, we found a low positive correlation between the ACh levels and corticosterone levels, depending on the presence of gonadal steroid hormone. We conclude that: 1) gonadal steroid hormones maintain the stress response of ACh levels in the hippocampus, 2) the gonadal steroid hormone independently regulates the stress response of ACh in the hippocampus and serum corticosterone, and 3) the sex-specific action of gonadal hormone on the cholinergic stress response may suggest a neonatal sexual differentiation of the septohippocampal cholinergic system in rats.
Chlorine - An Introduction
Authors: Porter George
Published: October 2007

Chlorine, in the form of its salts, has been known since the earliest days of recorded history, although its recognition as an element did not occur until the beginning of the nineteenth century when its very high reactivity as an oxidant was found remarkable after it was shown not to contain any oxygen. Its absorption by sunlight made it a key substance in the early development of photochemistry. One example of this, with both pure and applied aspects, is described in more detail. The free radical chloric oxide played an important role in the development of the technique of flash photolysis and twenty five years later these researches were of essential importance in showing how chlorine and its oxides were involved in the destruction of the ozone layer by the chlorofluorocarbons.
The Chlorine Industry
Authors: Fauvarque Jacqueline
Published: October 2007

Numerous products, such as polymers, chemicals or pharmaceuticals and ultra-pure metals, which often do not actually contain chlorine, are produced using either chlorine or its derivatives. They are essential in all industrial sectors and in our daily lives. New chlorine production units have adopted the membrane electrolytic process, but the century-old diaphragm and mercury processes retain their high-performance characteristics when appropriately modernised and improved.
Persistent, Ecotoxic and Bioaccumulative Compounds and their Possible Environmental Effects
Authors: Ballschmiter K.
Published: October 2007

The relationship between physicochemical properties, environmental distribution and effects of organochlorine compounds as a major class of persistent organic pollutants (POPs) are discussed. The environmental fate of a compound includes its transport and dispersion in the environment as well as its accumulation and transformation in defined environmental compartments. Accumulation and transformation as the result of environmental distribution may have long-term consequences; this is indicated by the ultimate accumulation and long-term bioactivity of several widely spread organochlorines, and is clearly evident in the decomposition of chlorofluorocarbons in the stratosphere.

Depending on the order of trophic levelsbiomagnifiaction factors of 10,000 up to 100,000 are encountered for persistentsemivolatile organochlorines such as 4,4'-DDE, PCB congeners or some Toxapheneconstituents. Mammals show intra-species pollutant transfer during thelactation period. While the mother animal is partly depleting its bodyburden, the calve accumulates in a critical period of its life via themilk a concentrated input of persistent organochlorines. A similar depletionphenomenon is also found for fish and crustacean which enrich in the eggsa substantial part of the accumulated body burden of the female.

The air skimming of semivolatiles by plantsurfaces leads to surprisingly high levels of pollutants in the uppersoil layers of forests that otherwise would be considered pristine interms of human activities.
Toxicology of Environmentally Persistent Chlorinated Organic Compounds
Authors: Hanberg Annika
Published: October 2007

The chlorinated organic compounds comprise a large group of compounds with a complex diversity of biologic effects and mechanisms of action. Based on the persistence and high toxicity of dioxins, PCBs, and DDT, this chapter focuses primarily on the toxicology of these organochlorine compounds. Not even these groups of compounds can be regarded as homogenous since the individual congeners show diverse environmental fates and toxicities. In this chapter, we will consider primarily the critical effects suspected to occur at human exposure at background levels, i.e. cancer, and effects on reproduction, neurobehaviour and the immune system. In recent years, interactions between these compounds and hormonal systems have received increasing attention. They have also been shown to be particularly toxic to the developing embryo, fetus and infant. In order to conduct accurate risk assessment, there is a need for further mechanistical data, and additional epidemiological studies, especially with regard to effects on reproductive, neurobehavioural and immune systems. The data presently available suggest that such effects already occur in the human population and thus, in order to reduce the exposure to these compounds, further release into the environment should be prevented.
Organochlorine Waste Management
Authors: Papp Roger
Published: October 2007

Sound environmental management includes the proper management of waste. This chapter reviews the basic rules of good management practice illustrated by some examples from chlorine derivatives production and gives the main considerations governing the Best Available Techniques for organochlorine waste thermal treatment. A review of the main degradation pathways of organochlorines - dispersal, distribution, degradation pathways, and environmental half-lives - demonstrates a very large range of characteristics, justifying the need for a separate study for each substance. Finally, the paper examines the latest developments in organochlorine contaminated site remediation technology.
Visually mediating knowledge construction in project-based doctoral design research
Authors: Melles Gavin
Published: October 2007

Practice-based research projects in design often require students to construct contextual reviews of multiple fields. In this interdisciplinary territory of an emerging academic field, supervisors and students must work jointly to construct a mutually satisfactory outcome and avoid
producing a body of dissonant voices. Knowledge and practice precedents must be actively constructed into a coherent map of the research terrain so that the project focus can be foregrounded. While the project-based component of practice-based doctorates is familiar creative territory for
design students, balancing this with textual scholarship can lead to loss of focus and unstructured proliferation of sources.

The use of two-dimensional visualization strategies, such as mind-mapping, can contribute to clarifying research positions and gaps but has limited capacity to dynamically
integrate visual and textual sources. Digital visualization tools can facilitate the mutual student and supervisor organization of knowledge, exploit the visual literacy of design students and respond dynamically to project changes. This article shows how one visual tool may better mediate
supervisory dialogues with students particularly in the context of practice-based doctorates of design incorporating project components. Following a review of existing research visualization strategies, I exemplify the potential of a hypertext tool to mediate the supervision and knowledge
construction process with two narrative cases of student work.
The Definition of Hypotension in Very Low-birthweight Infants During the Immediate Neonatal Period
Authors: Weindling A. Michael , Subhedar Nim V.
Published: October 2007

The term “hypotension” can be simply an abnormally low blood pressure (BP). However, questions remain as to the lower limit of normal and the level of BP that requires treatment, especially in newborns. Several approaches have been proposed for defining hypotension in the neonate, in whom a host of infant factors cause variations in BP. Natural compensatory mechanisms contribute to maintaining BP and subsequent tissue oxygen delivery. Therefore, an individualized approach to determining tissue perfusion and preventing tissue damage as well as acceptance of lower levels of BP may be appropriate.
Predischarge Risk Assessment for Severe Neonatal Hyperbilirubinemia
Authors: Keren Ron , Bhutani Vinod K.
Published: October 2007

Current approaches to identifying infants at risk of developing severe neonatal hyperbilirubinemia include use of an hour-specific bilirubin nomogram that employs predischarge bilirubin measurements and clinical risk factor assessment that employs multiple factors in clinical prediction rules. Determining the hour-specific total serum bilirubin before discharge has been shown to be the most accurate method for assessing risk of severe hyperbilirubinemia. Combining clinical risk factors and predischarge bilirubin values may offer additional predictive performance above either approach used alone. Current risk assessment strategies need to be validated prospectively in a large and diverse newborn population, and the risk assessment strategies should be paired with recommended actions. Finally, transcutaneous bilirubin and end-tidal carbon monoxide measurements and screening for specific genetic markers of neonatal hyperbilirubinemia have the potential to refine risk assessment strategies further.
Pharmacology Review
Authors: Natarajan Girija , Lulic-Botica Mirjana , Aranda J.V.
Published: October 2007

Caffeine is used commonly in the neonatal intensive care unit to treat apnea of prematurity. This review describes the mechanism of action, pharmacokinetics, and therapeutic role of caffeine. Published data on its efficacy and safety document that caffeine can reduce the frequency of apneic episodes and appears safe in the short term.
Non-tectonic deformations of Pleistocene sediments in the eastern Paris basin, France
Authors: Baize Stéphane , Coulon Michel , Hibsch Christian , Cushing Marc , Lemeille Francis , Hamard Erwan
Published: October 2007

Deformations observed within Quaternary alluvium in the Champagne region (Paris Basin) comprise faults, folds and soft-sediment deformation structures. Their occurrence is linked to the subjacent weathered chalk. Previously interpreted as neotectonic features, the deformations are reinterpreted as karst subsidence features or/and soil displacements due to periglacial processes. Dissolution of chalk has produced superficial subsidence, explaining the geometry of some faults and their large offsets within surface deposits. The freezing-thawing cycles in the porous superficial layers have also favoured gravity instability and deformations, and this can explain local small-scale deformations but also mass movement (sliding). The seismotectonic hypothesis is rejected, because of the absence of regional faults able to generate such large co-seismic offsets. The fault directions and the apparent vertical offsets are not homogeneous at regional scale and they are often inconsistent with the Quaternary stress field. Moreover, the rooting of faults into the basement is not documented and therefore, the neotectonic origin is very doubtful.
Require Safer Substitutes and Solutions: Making the Substitution Principle the Cornerstone of Sustainable Chemical Policies
Authors: Thorpe Beverley , Rossi Mark
Published: October 2007

Currently, chemical regulations in the United States do not prioritize the production and use of inherently safe chemicals. At present, when regulations get passed to target a chemical for control, safer substitutes are not the goal nor are there specific guidelines or tools used to achieve Green Chemistry, Clean Production, or sustainable product design. In most cases, the replacement is often just as hazardous or simply a reduction of the quantity or concentration of the toxic substance that has been targeted. In contrast, by placing the Substitution Principle at the heart of new chemical policies and regulations, hazardous chemicals would be replaced with less hazardous alternatives or preferably alternatives for which no hazards can be identified. This would hasten the uptake of Green Chemistry, or environmentally benign chemical synthesis. Substituting hazardous chemicals goes beyond finding a drop-in chemical alternative and can include systems, materials or process changes. Regulatory drivers include a clear timeline for phase out of priority chemicals based on their inherent hazard, mandatory substitution planning for hazardous chemicals, financial and technical support for companies to find safer materials, and increased funding for green chemistry development and uptake by companies.
Two Bronze Medals for Switzerland at the 39th International Chemistry Olympiad 2007 in Moscow
Authors: Cosandey Maurice
Published: October 2007

Delegations from 68 countries took part to the 39th International Chemistry Olympiad in Moscow, 15–24 July, 2007. Lucia Meier, from Frick AG, and Max Häfliger from Luzern both won two bronze medals for Switzerland.
Thermodynamic modeling of the stability and melting properties of sodium borates relevant to black liquor combustion and gasification
Authors: Lindberg Daniel , Backman Rainer , Hupa Mikko
Published: October 2007

The use of borates as an autocausticizing agent in kraft recovery boilers of pulp mills is an interesting concept for decreasing the lime consumption at pulp mills. The main autocausticizing reaction is between NaBO2and Na2CO3 forming Na3BO3 and CO2 at high temperatures in a liquid phase in the recovery boiler. The thermodynamic and phase equilibrium data of the Na2CO3 – NaBO2 – Na3BO3 system were evaluated and optimized. The liquid phase was modeled with the modified quasichemical model. The thermodynamic database obtained can be used to calculate the phase equilibrium and thermodynamic properties of multicomponent sodium salt mixtures of importance for the borate autocausticizing concept. The thermodynamic database is a part of an extensive thermodynamic database for alkali salt mixtures of importance for black liquor combustion in the pulp and paper industry.
Safety Standards for High-Speed Rail Transportation
Authors: Rao Alan , Tsai Tom
Published: October 2007

As China, including Taiwan, moves into a new age of high-speed rail (HSR) transportation, it is essential that an infrastructure of safety organizations and regulations be established to ensure the safe operation of such systems when they are ready. Various organizations and safety standards that regulate safety of HSR operations in Europe, Japan, and the United States are described so that the government of China, as it moves into private and regional entities, can establish a regulatory structure to plan, develop, and monitor the safety of future HSR operations, regardless of the system built. Some operational experience and issues will be used to illustrate the problems associated with current practices in the United States.
Biographical Notes
Authors: Alexander Catherine , Aplenc Veronica E. , Carbonella August , Choltaev Zaindi , Eriksen Thomas Hylland , Filippucci Paola , Giordano Christian , Humphrey Caroline , Kaneff Deema , King Alexander D. , von Lewinski Silke , Pohl Michaela , Rebel Hermann , Volčič Zala
Published: October 2007

Biographical notes on contributors
Europe, the Pope and the Holy Left Alliance in Poland
Authors: Pobłocki Kacper
Published: October 2007

This article describes why the Polish government has pushed for an invocation to Christian traditions in the European Union Constitution. It is argued that this is a rather 'unfortunate' outcome of the political alliance between the Catholic Church and the Polish left, especially between President Aleksander Kwaśniewski and the Democratic Left Alliance (SLD). This alliance allowed the SLD to legitimize their rule in the post-socialist Poland, and it was a result of a political competition between them and the post-Solidarność elites. As a result, John Paul II became the central integrative metaphor for the Polish society at large, which brought back in the marginalized as well as allowed the transition establishment to win the EU accession referendum in 2003. The article (which was written when Leszek Miller was still Prime Minister) demonstrates how this alliance crystallized and presents various elements of the cult of the Pope in Poland that followed. Finally, it argues that the worship of the Pope is not an example of nationalism, but of populism, understood not as a peripheral but as a central political force, and advocates for more research on the 'politics of emotions' at work in the centers and not in peripheries.