bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulo groups
Authors: MacKinnon Nick
Published: January 2007

The set of whole numbers less than and coprime to n, with the operation of multiplication modulo n, forms an Abelian group (try to prove it for yourselves). We'll write Mn for this group, and call all such groups modulo groups or M-groups. M-groups are easy to compute. It is also particularly easy to calculate quotient groups of M-groups, making them a good source of examples and practice for the beginner. There are also some very hard, possibly unsolved, problems in classifying M-groups. In attacking such problems there is an interaction between number theoretical and group theoretical arguments which makes this a rich topic, for projects or personal pleasure.
Steiner-Lehmus and the Feuerbach triangles
Authors: Parry C. F.
Published: January 2007

In the geometry of the triangle, the Feuerbach quadrangle comprises the four points of contact between the nine point circle and the four tritangent circles. By omitting each of the four points in turn, we create four Feuerbach triangles. When the basic triangle is isosceles we find that two of the four points of contact coincide and the resultant single Feuerbach triangle is also isosceles. In the spirit of Steiner-Lehmus we address the converse question – if one of the Feuerbach triangles is isosceles, is the basic triangle necessarily isosceles? The answer is negative.
Applications of the pigeon-hole principle
Authors: Bankov Kiril
Published: January 2007

Consider the statement (whose truth is obvious):

If n objects are placed in k boxes, where n = qk + r, q and r are positive integers, and 0 < r < k, then at least one box contains more than q objects.

This is known as a pigeon-hole principle (or Dirichlet’s). It is one of the strategies which is often used for problem-solving. Although it is one of the most powerful tools of combinatorics, the principle can be used successfully in other branches of mathematics. Below you can find a collection of problems which can be solved easily by applying this principle to geometrical objects.
Aims – the 1993 Presidential Address
Authors: Hersee John
Published: January 2007

With so much changing almost daily in schools and education, it has been difficult to decide on a title for this address and even more difficult to finalize a text. Some of the titles I’ve considered are shown here.
Minimum wage policy
Authors: Robin Anthony C. , Lord Nick
Published: January 2007

Before the last General Election politicians were arguing about the effects of a minimum wage policy. One was suggesting that we should have a minimum wage that was a certain percentage of the mean wage, while another claimed that such a policy would be inflationary, with wages spiralling up like a dog chasing its tail. What struck me was if you give some people an increase in salary to a fraction of the mean salary then you’ve increased the mean, so you’ll have to do it again. Might this process not lead to wages spiralling up to infinity?
A salutary or solitary point
Authors: Hoare Graham
Published: January 2007

Some three weeks into the academic year I presented, off the cuff, the following morsel to engage some lower-sixth formers who had polished off some routine derivatives all too quickly:

Sketch the curve whose equation is given by x3 + y3 + 3xy – 1 = 0 , and find the gradient at the point (–1 , –1).

Since this was near the end of a double period I thought no more of it. At the end of the next double period one student remarked that he had been having difficulty in sketching it. “It seems to be a straight line”, he said. I rashly suggested that he could well be mistaken, but promised to look at it. If my faith in the student had been greater I could have saved myself some labour searching for simple solutions of the cubic. I had noticed the solution (½ , ½) by the way. I began to have delusions of grandeur, imagining myself to be the natural successor of Diophantus, as I found the solutions (5,–4) and (–4,5).
Icebows
Authors: Reade John B.
Published: January 2007

The picture of a rainbow on the front cover of this issue of the Gazette was taken by Nicholas Robins in May 1993. He was mystified that the rainbow was upside down, and wrote to the ‘Notes and Queries’ column in the Guardian asking if anyone could explain why. From subsequent correspondence and discussion it emerged that there were further irregularities. Firstly, it was not raining. Rainbows are caused by refraction of light through spherical raindrops, so how could you have a rainbow with no raindrops? Secondly, this rainbow was in the same direction as the sun. To see a normal rainbow you have to stand with your back to the sun.
Roll-a-penny probabilities
Authors: Hirst Ann
Published: January 2007

In exploring the probabilities involved in a roll-a-penny game, some properties turned out to be a little more complicated than expected. The main aim here is to find the probability that the player will lose after a certain number of rolls.

Suppose we have a board upon which squares are drawn, and that the side of each square is four times the radius of a penny. (In practice, this means that the squares are of side 4 cm.) The first question is, “What is the probability that the penny lands entirely within a square, assuming that the dividing lines are of negligible thickness?”
Mathematical proofs in the computer age
Authors: Devlin Keith
Published: January 2007

As recently as ten years ago, professional mathematicians did most of their work at a desk, using paper and pencil. Today’s mathematician still sits at a desk, but facing a cathode-ray screen. The paper and pencil are still there, but a lot of the mathematician’s activities now involve use of the computer. In particular, powerful computer packages like Mathematica and Maple advertise themselves as systems for ‘doing mathematics on a computer’. This rapid transformation has changed the nature of doing mathematics in a fundamental way. The computer does not simply ‘assist’ the mathematician in doing business as usual; rather, it changes the nature of what is done. In particular, the logical structure of mathematical reasoning carried out with the aid of an interactive computer system is different from the structure of the more traditional form of mathematical reasoning. This article is a logician’s view of the ‘new maths’ of the computer age.
The concept of ‘rigorous proof’
Authors: Dieudonné Jean
Published: January 2007

Mathematicians of every age have been seen to criticize the proofs of their predecessors or of their contemporaries as ‘not being rigorous’; and often those which they proposed as replacements for the defective proofs were in their turn considered inadequate by the succeeding generation. This apparent repeated putting into question of mathematicians' arguments at length led some people to think these arguments contained a hidden flaw which meant that a proof could never be found unassailable by any criticism.
Proscheeding unshtedily to a limit . . .
Authors: Watson F. R.
Published: January 2007

It is well known that as I was trying to illustrate this to some students by calculating and so on, using the ‘story’ about a sum of £1 invested at 100% interest. After one year this would yield £2 if interest is added annually, £2.25 if added (compounded) at each half-year, £2.37 if compounded every 4 months, and so on.
Large prime quadruplets
Authors: Forbes Tony
Published: January 2007

With one exception, namely {2, 3, 5, 7}, it is impossible to have four consecutive primes p1, p2, p3, p4 with p4 - p1 < 8. An interval of seven or less cannot contain more than three odd numbers unless one of them is a multiple of three. On the other hand, groups of four primes p, p + 2, p + 6, p + 8, usually called prime quadruplets, are fairly common. The first is {5, 7, 11, 13}, followed by {11, 13, 17, 19}, {101, 103, 107, 109}, {191, 193, 197, 199}, {821, 823, 827, 829} and so on. Just as with prime twins, pairs of primes p, p + 2, it is conjectured that the sequence of prime quadruplets goes on for ever. Indeed, the apparently simpler prime twin conjecture is currently an unsolved problem of mathematics although in 1973, Jing-Run Chen proved a weaker form: There are infinitely many primes p such that p + 2 is either prime or the product of two primes (See Halberstam & Richert [1]). A similar result holds for quadruplets [1, Theorem 10.6]: There exist infinitely many primes p such that (p + 2) (p + 6) (p + 8) has at most 14 prime factors. The prime quadruplet conjecture would then follow if we could reduce ‘14’ to ‘3’ but this seems be a problem of extreme difficulty.
Divisors of n!
Authors: Hirst Keith
Published: January 2007

This article arose out of a first year undergraduate class project concerned with divisors. The class was presented with a sheet containing the prime factorisations and a list of divisors for the natural numbers up to 120. Among the many observations and conjectures which the students formulated some were related to the standard result about the number of divisors in terms of the prime factorisation. One conjecture made by several students which was not in the textbooks was d(n!) = 2n-1 where d(k) denotes the number of positive divisors of k. The result is true for n = 2, 3, 4, 5, which takes one to the limit of the data sheet given to the students (5! = 120). Unfortunately it breaks down for n = 6, since d(5!) = 16 but d (6!) = 30 and not 32. Several students reported that they had reached their conjecture on the basis that they thought the number of divisors of n! would double every time n increased by 1.
Physical Geography and Settlements
Authors: Wagstaff Malcolm
Published: January 2007

Physical conditions have an important and many-faceted influence upon the human occupation and use of an area. Their influence is not always direct, but depends upon the perception of the physical environment by a resident or immigrant group. Only a part of the perceived environment affects decisionmaking and influences behavioural patterns as expressed, for example, in the siting of settlements and the use of land for subsistence. Behaviour, in turn, not only affects the physical environment – by the clearance of forest, for example – but also influences the way in which the physical environment is perceived. Continuous reappraisal is thus integral to successful human occupation and use of an area. Accordingly, established patterns may change, perhaps almost imperceptibly but sometimes radically. The mere existence of an established pattern, however, shapes subsequent reappraisals and, to some extent, controls necessary modifications and changes. A model of geographical change through time is thus more spiral than linear.
Mr. Taylor in Chaldaea.
Authors: Sollberger E.
Published: January 2007

The very first reports on excavations at sites in southern Sumer appeared in the Journal of the Royal Asiatic Society for 1855 under the name of ‘J. E. Taylor, Esq.’ A typographer's misreading thus gave Taylor the wrong initials under which he is usually mentioned. His middle name was in fact George. It may, of course, seem surprising that the author himself did not bother to correct the error. One can only suppose that, postal communications being what they were at the time (see below, §6), he never had a chance of seeing his articles in proof.

Very little seems to be known of John George Taylor's life and career. According to information kindly supplied by Miss S. Johnson, India Office Records, he was the son of R. Taylor, “almost certainly Colonel R. Taylor”, Rawlinson's predecessor at Baghdad. If so, it is remarkable that the latter does not seem to mention the fact in his correspondence with the British Museum. What is certain is that J. G. Taylor was The Hon. East India Company's Agent and H.M. Vice-Consul at Basrah from 1851 to 1859. In 1853 he started his explorations of the “Chaldaean Marshes” for and on behalf of the British Museum under the very strict instructions and supervision of Rawlinson who, as The Hon. East India Company's Political Agent in Turkish Arabia and H.M. Consul-General at Baghdad, was then presiding over Mesopotamian archaeology with truly vice-regal grandeur and an almost proprietary interest.
Eine frühurartäische Siegesdarstellung
Authors: Calmeyer P. , Seidl U.
Published: January 2007

Die einstmals kreisrunde, flache Bronzescheibe, angeblich aus Ostanatolien, die hier vorgestellt wird (Pl. XXX–XXXI), befand sich 1981 für kurze Zeit im Labor der Prähistorischen Staatssammlung, München. Die Form des Bleches, die bisher bekannten Beschlagblechen nicht genau entspricht, die historische Darstellung auf dem umlaufenden Fries und das Mittelemblem verdienen eine genauere Behandlung.

Die Scheibe: Die durchschnittlich auf eine Dicke von ungefähr 1/2 mm. ausgehämmerte Bronzescheibe wird durch 4 konzentrische getriebene Wülste in einen mittleren Kreis, drei Zonen und einen Rand aufgeteilt (Fig. 1, Pl. XXXa). Im Übrigen ist sie ganz flach, und das dürfte auch ihrem antiken Zustand entsprechen: sie muß allerdings einmal brutal quer gefaltet gewesen sein, wovon eine Reihe von Rissen und Knicken herrühren, die von links unten nach rechts oben verlaufen (Pl. XXXa); an den Enden dieser Faltung ist auch der Rand am weitesten ausgerissen. Die nachträgliche Begradigung dieser Partie ist wohl modern. Links oben und rechts unten jedoch ist der offenbar ursprünglache flache Zustand bewahrt.
Two New Milestones from Pisidia
Authors: Horsley G. H. R.
Published: January 2007

By the end of 1987 three successive seasons had been spent by a team co-directed by Dr. S. Mitchell and Professor M. Waelkens at the Augustan colony of Cremna, and two (plus a brief initial season in 1985) at Pisidia's chief city in Roman Imperial times, Sagalassos. The permit for a surface survey has provided the opportunity to locate and check a considerable percentage of the texts previously known. It has also made possible the discovery of several new inscriptions from these sites and their territory. Two new milestones are presented here, one pertaining to each city.

In early August 1987, on the last evening of my stay with the team working at Sagalassos, I was taken by two men from Aǧlasun 4 km. along the Aǧlasun–Isparta road. Turning right into a lane, after some 300 m. we came to a small bridge over a stream. Nearby was a large cylindrical stone (Pl. XVII(a)) which had recently been recovered from the stream during excavations for another bridge.
Association study of polymorphisms in the glutamate transporter genes SLC1A1, SLC1A3, and SLC1A6 with schizophrenia
Authors: Deng Xiangdong , Shibata Hiroki , Takeuchi Naoko , Rachi Shinako , Sakai Mayumi , Ninomiya Hideaki , Iwata Nakao , Ozaki Norio , Fukumaki Yasuyuki
Published: January 2007

Based on the glutamatergic dysfunction hypothesis for schizophrenia pathogenesis, we have been performing systematic association studies of schizophrenia with the glutamate receptor and transporter genes. We report here association studies of schizophrenia with three glutamate transporter genes SLC1A1, SLC1A3, and SLC1A6 encoding the glutamate transporters EAAT3, EAAT1, and EAAT4, respectively. We initially performed the screening of the total 25 single nucleotide polymorphisms (SNPs) distributed in the three gene regions using 100 out of 400 Japanese cases and 100 out of 420 Japanese controls. After controlling the false discovery rate (FDR) at level 0.05, we observed significant associations of schizophrenia with a genotype of SNP4 (rs2097837, P = 0.007) and with haplotypes of SNP2‐SNP5 (P = 7.5 × 10−5) and SNP3‐SNP5 (P = 9.0 × 10−4) in the SLC1A6 region. The haplotype of SNP2‐SNP5 of SLC1A6 even showed marginally significant association with the disease in the full‐size sample (400 cases and 420 controls, P = 0.031). We concluded that at least one susceptibility locus for schizophrenia may be located within or nearby SLC1A6, whereas SLC1A1 and SLC1A3 are unlikely to be major susceptibility genes for schizophrenia in the Japanese population. © 2006 Wiley‐Liss, Inc.
Differential expression and parent‐of‐origin effect of the 5‐HT2A receptor gene C102T polymorphism: Analysis of suicidality in schizophrenia and bipolar disorder
Authors: De Luca Vincenzo , Likhodi Olga , Kennedy James L. , Wong Albert H.C.
Published: January 2007

The serotonin 2A (5‐HT2A) receptor gene has been implicated in the pathogenesis of suicidal behavior by a genetic association between the 5‐HT2A C102T silent polymorphism and suicidality in patients with major depression. However, a recent meta‐analysis failed to confirm this association. We developed an improved quantitative assay for the measurement of allele‐specific expression of the 5‐HT2A gene, and find that the ratio of C/T allele expression in the pre‐frontal cortex of heterozygous suicide victims (n = 10) was significantly decreased in comparison with the non‐suicide group (n = 10) (P = 0.049). Because the 5‐HT2A gene is subject to imprinting, the parent‐of‐origin may affect the inheritance of suicidal behavior. Thus we examined the parental origin of specific alleles for genetic association in a genetic family‐based sample of major psychoses in which information on suicidal behavior was available. No association between the 5‐HT2A C102T polymorphism and suicidal behavior in major psychoses was detected with the transmission/disequilibrium test (TDT). © 2006 Wiley‐Liss, Inc.
Actimetric evidence that CLOCK 3111 T/C SNP influences sleep and activity patterns in patients affected by bipolar depression
Authors: Benedetti Francesco , Dallaspezia Sara , Fulgosi Mara Cigala , Lorenzi Cristina , Serretti Alessandro , Barbini Barbara , Colombo Cristina , Smeraldi Enrico
Published: January 2007

Depressive insomnia and diurnal fluctuations of mood and activity are core clinical features of mood disorders. Here we studied the effect of CLOCK 3111 T/C SNP (rs1801260) on the actimetric recorded diurnal activity and nocturnal sleep of 39 bipolar depressed inpatients. Compared to T/T homozygotes, carriers of the C allele had a similar degree of severity of depression, but showed higher activity levels in the evening, a delayed sleep onset (mean 79 min later), and a reduced amount of sleep during the night (mean 75 min less). Ongoing lithium treatment significantly interacted with rs1801260 by enhancing activity levels in the evening and reducing the differences among genotype groups. Individual characteristics of the molecular clock can influence sleep symptoms in mood disorders. © 2007 Wiley‐Liss, Inc.
Innentitelbild: Synthesis of Palladium Icosahedra with Twinned Structure by Blocking Oxidative Etching with Citric Acid or Citrate Ions (Angew. Chem. 5/2007)
Authors: Xiong Yujie , McLellan Joseph M. , Yin Yadong , Xia Younan
Published: January 2007

Oxidative Ätzprozesse zerlösen oft mehrfach verzwillingte Partikel bei typischen Synthesen von Palladiumnanostrukturen in Lösung, und speziell die starke Bindung von Sauerstoff an die Palladiumoberfläche macht diesen Vorgang schwer vermeidbar. In ihrer Zuschrift auf S. 804ff. zeigen Y. Xia und Mitarbeiter, dass Zitronensäure oder Citrationen ein chemisches Ätzen verhindern, indem sie an der Oberfläche chemisorbieren (siehe Bild). Dadurch werden verzwillingte Palladium‐Ikosaeder in bis zu 80% Ausbeute erhalten.
Cover Picture: Acid Initiation of Ammonia–Borane Dehydrogenation for Hydrogen Storage (Angew. Chem. Int. Ed. 5/2007)
Authors: Stephens Frances H. , Baker R. Tom , Matus Myrna H. , Grant Daniel J. , Dixon David A.
Published: January 2007

Hydrogen meets the world's need for a carbon‐neutral and particulate‐free vehicular fuel, but its low density hampers on‐board storage capacity. In their Communication on page 746 ff., R. T. Baker, D. A. Dixon, and co‐workers present a strategy for hydrogen storage using ammonia–borane (H3NBH3), which has a hydrogen capacity of 19.6 wt %—exceeding that of gasoline. They report the mechanism of acid‐initiated dehydropolymerization of H3NBH3 as elucidated through experimental and computational methods.
Inside Cover: Synthesis of Palladium Icosahedra with Twinned Structure by Blocking Oxidative Etching with Citric Acid or Citrate Ions (Angew. Chem. Int. Ed. 5/2007)
Authors: Xiong Yujie , McLellan Joseph M. , Yin Yadong , Xia Younan
Published: January 2007

Oxidative etching usually dissolves multiply twinned particles in typical solution‐phase syntheses of Pd nanostructures. The strong binding of oxygen to the Pd surface makes this etching process difficult to avoid. In their Communication on page 790ff., Y. Xia and co‐workers demonstrate that citric acid or citrate ions can prevent oxidative etching through chemisorption (see picture), which allows twinned Pd icosahedra to be formed in yields as high as 80%.
Assessment of Chelatable Mitochondrial Iron by Using Mitochondrion‐Selective Fluorescent Iron Indicators with Different Iron‐Binding Affinities
Authors: Rauen Ursula , Springer Andrea , Weisheit Daniela , Petrat Frank , Korth Hans‐Gert , de Groot Herbert , Sustmann Reiner
Published: January 2007

Chelatable cellular iron, and chelatable mitochondrial iron in particular, has yet to be well characterized, so the overall strength with which these “loosely bound” iron ions (presumably mainly FeII) are intracellularly/intramitochondrially bound is unclear. We have previously reported the first selective mitochondrial iron indicator: rhodamine B 4‐[(1,10‐phenanthrolin‐5‐yl)aminocarbonyl]benzyl ester (RPA). With this compound as a model, we have now developed two additional mitochondrial iron indicators with very different iron‐binding affinities and have applied these to the study of the chelatable iron pool in the mitochondria of isolated rat liver cells. With the new indicator rhodamine B 4‐[(2,2′‐bipyridin‐4‐yl)aminocarbonyl]benzyl ester (RDA), with 2,2′‐bipyridine as chelating unit (log β3=17.5), essentially the same iron concentration (16.0±1.9 μM) was determined as with RPA (log β3=21.1), despite the four orders of magnitude difference in FeII‐binding affinity. This not only demonstrates the reliability of the procedure, but also confirms that iron complexation by these indicators does not induce any significant release of iron from the iron‐storage proteins on the timescale of the experiment. In contrast, the indicator rhodamine B 4‐[bis(pyridin‐2‐ylmethyl)aminomethyl]benzyl ester (PIRO), with anN,N‐bis(pyridin‐2‐ylmethyl)amine group as chelating component (log β2=12.2), could not compete against the array of endogenous ligands. The intramitochondrial concentrations of the three indicators were determined to be in the range of 100 μM: that is, about three orders of magnitude lower than the total concentration of endogenous compounds that might chelate iron ions. It is therefore estimated that chelatable mitochondrial iron ions are bound by endogenous ligands with apparent stability constants (log Kapp) of between 9 and 14.
Secondary cytoreductive surgery for localized, recurrent epithelial ovarian cancer
Authors: Salani Ritu , Santillan Antonio , Zahurak Marianna L. , Giuntoli Robert L. , Gardner Ginger J. , Armstrong Deborah K. , Bristow Robert E.
Published: January 2007

BACKGROUND.

The objective of this study was to evaluate the role of secondary cytoreductive surgery in the outcome of patients who had recurrent epithelial ovarian carcinoma that was limited to ≤5 recurrence sites within the abdomen or pelvis on preoperative imaging studies and attempt to define selection criteria associated with improved survival, with specific attention to the number of lesions suspicious for recurrent disease.

METHODS.

Patients who underwent secondary surgical cytoreduction for recurrent epithelial ovarian cancer between September 1997 and March 2005 were identified retrospectively from tumor registry databases. Study inclusion criteria required a complete clinical response to primary therapy, ≥12 months between initial diagnosis and recurrence, and ≤5 recurrence sites on preoperative imaging studies. Univariate and multivariate logistic regression analyses were used to evaluate the effect of clinicopathologic variables on overall postrecurrence survival.

RESULTS.

Fifty‐five patients met the study inclusion criteria. The median patient age at recurrence was 57.7 years, and the median diagnosis‐to‐recurrence interval was 32 months (range, 12–164 months). Complete cytoreduction was achieved in 41 patients (74.5%). On multivariate analysis, the statistically significant and independent predictors of overall survival were a diagnosis‐to‐recurrence interval ≥18 months (median survival, 49 months vs 3 months; P < .01), the number of radiographic recurrence sites (median survival, 50 months for patients with 1 or 2 sites vs 12 months for patients with 3 to 5 sites; P < .03), and residual disease (median survival, 50 months for patients with no macroscopic residual disease vs 7.2 months for patients with macroscopic residual disease; P < .01). Age, tumor grade, histology, CA‐125 level, ascites, and tumor size were not associated significantly with survival.

CONCLUSIONS.

The current data supported the definition of localized recurrent ovarian cancer as patients with 1 or 2 radiographic recurrence sites. In this select population, a diagnosis‐to‐recurrence interval ≥18 months and complete secondary surgical cytoreduction, which was achievable in the majority of patients, were associated with a median postrecurrence survival of approximately 50 months. Cancer 2007. © 2007 American Cancer Society.
A pilot study of the vulnerable elders survey‐13 compared with the comprehensive geriatric assessment for identifying disability in older patients with prostate cancer who receive androgen ablation
Authors: Mohile Supriya G. , Bylow Kathryn , Dale William , Dignam James , Martin Kandis , Petrylak Daniel P. , Stadler Walter M. , Rodin Miriam
Published: January 2007

BACKGROUND.

Impairments in geriatric domains adversely affect health outcomes of the elderly. The Comprehensive Geriatric Assessment (CGA) is a key component of the treatment approach for older cancer patients, but it is time consuming. In this pilot study, the authors evaluated the validity of a brief, functionally based screening tool, the Vulnerable Elders Survey‐13 (VES‐13), for identifying older patients with prostate cancer (PCa) with impairment in the oncology clinic setting.

METHODS.

Patients with PCa aged ≥70 years who actively were receiving androgen ablation treatment and who were followed within the clinics at the University of Chicago were eligible. Patients self‐completed the VES‐13 and CGA instruments and repeated the VES‐13 1 month later. Physical performance and cognitive assessments were administered by a research assistant.

RESULTS.

Of 50 participating patients, 50% were identified as impaired by the VES‐13 (score ≥3). Sixty percent of patients scored as impaired on ≥2 tests within the CGA, exhibiting deficits in multiple domains. The reliability of the VES‐13 (Pearson correlation coefficient) was 0.92. The cut‐off score of 3 on the VES‐13 had 72.7% sensitivity and 85.7% specificity for CGA deficits and was highly predictive for identifying impairment (area under the receiver operating characteristic curve, 0.90). Patients who had mean VES‐13 scores ≥3 performed significantly worse on evaluations of activities of daily living (P = .001), physical performance (P = .002), comorbidity (P = .004), and cognitive impairment (P = .003).

CONCLUSIONS.

Functional and cognitive impairments are highly prevalent among older patients with PCa who receive androgen ablation in oncology clinics. The current results indicated that the brief VES‐13 performed nearly as well as a conventional CGA in detecting geriatric impairment in this population. Cancer 2007. © 2007 American Cancer Society.
Glutamate AMPA/kainate receptors, not GABAA receptors, mediate estradiol‐induced sex differences in the hypothalamus
Authors: Todd Brigitte J. , Schwarz Jaclyn M. , Mong Jessica A. , McCarthy Margaret M.
Published: January 2007

Sex differences in brain morphology underlie physiological and behavioral differences between males and females. During the critical perinatal period for sexual differentiation in the rat, gonadal steroids act in a regionally specific manner to alter neuronal morphology. Using Golgi‐Cox impregnation, we examined several parameters of neuronal morphology in postnatal day 2 (PN2) rats. We found that in the ventromedial nucleus of the hypothalamus (VMN) and in areas just dorsal and just lateral to the VMN that there was a sex difference in total dendritic spine number (males greater) that was abolished by treating female neonates with exogenous testosterone. Dendritic branching was similarly sexually differentiated and hormonally modulated in the VMN and dorsal to the VMN. We then used spinophilin, a protein that positively correlates with the amount of dendritic spines, to investigate the mechanisms underlying these sex differences. Estradiol, which mediates most aspects of masculinization and is the aromatized product of testosterone, increased spinophilin levels in female PN2 rats to that of males. Muscimol, an agonist at GABAA receptors, did not affect spinophilin protein levels in either male or female neonates. Kainic acid, an agonist at glutamatergic AMPA/kainate receptors, mimicked the effect of estradiol in females. Antagonizing AMPA/kainate receptors with NBQX prevented the estradiol‐induced increase in spinophilin in females but did not affect spinophilin level in males. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Nitric oxide modulates sodium taste via a cGMP‐independent pathway
Authors: Schuppe H. , Cuttle M. , Newland P.L.
Published: January 2007

Insects, like other animals, require sodium chloride (NaCl) as part of their normal diet and detect it with contact chemoreceptors on the body surface. By adjusting the responsiveness of the chemosensory neurons within these receptors insects can modify the intake of salt and other nutrients, and it has been hypothesized that the responsiveness of chemosensory neurons is regulated by nitric oxide (NO). To identify potential sources of NO in the periphery, the authors applied the NO‐sensitive fluorescent probe 4,5‐diaminofluorescein and the universal NO synthase antibody, and found that in locusts NO is synthesized within one particular class of cells of the epidermis, the glandular cells, from where it may diffuse to neighboring chemosensory neurons. The effects of NO on chemosensory neurons were investigated by recording from contact chemoreceptors on the leg while perfusing it with drugs that interfere with NO signaling. Results showed that both endogenous and exogenous NO decreased the frequency of action potentials in chemosensory neurons in response to stimulation with NaCl by acting via a cyclic guanosine monophosphate‐independent pathway. Variation of the NaCl concentration in the perfusion solution demonstrated that the synthesis of NO in glandular cells depends on the NaCl concentration in the hemolymph. By contrast NO increased the frequency of action potentials in chemosensory neurons in response to sucrose stimulation. The authors suggest that NO released from glandular cells modulates the responsiveness of chemosensory neurons to regulate NaCl intake, and hypothesize that NO may play a key role in the signaling of salt and sugars. © 2006 Wiley Periodicals, Inc. Develop Neurobiol 67: 219–232, 2007.
Nicotine regulates mRNA expression of feeding peptides in the arcuate nucleus in neonatal rat pups
Authors: Huang L.Z. , Winzer‐Serhan U.H.
Published: January 2007

Maternal smoking results in low birth weight. Using a neonatal gastric intubation model corresponding to the third trimester in humans, nicotine, the major psychoactive ingredient in tobacco, causes growth retardation in rat pups. Here, we wanted to determine the underlying mechanisms of nicotine's anorexic effects. In adults, body weight and energy expenditure are regulated by the adiposity hormone leptin and the orexigenic peptides neuropeptide Y (NPY) and agouti‐related peptide (AgRP) and anorexic peptides proopiomelanocortin (POMC) and cocaine‐ and amphetamine‐regulated transcript (CART) expressed in the hypothalamic arcuate (Arc) nucleus. Activation of nicotinic acetylcholine receptors (nAChRs) could regulate leptin release and/or peptide expression in the Arc. Neonatal rat pups were treated twice daily with nicotine (0.25, 1.5, and 3 mg/kg) from postnatal day 1 to 8 (P1–8). This resulted in an upregulation of heteromeric nAChR binding sites in the ventromedial nucleus of the hypothalamus and Arc. Nicotine at all three doses significantly reduced body weight gain and increased mRNA expression of NPY, AgRP, and POMC effects, which were blocked by dihydro‐β‐erythroidine (DHβE), an α4β2* nAChR antagonist, but CART expression was unaffected. In contrast, serum leptin levels were significantly increased only by 3 and 1.5 mg/kg, and the increase was only partially blocked by DHβE. These data suggest that in neonates chronic nicotine regulates body weight gain independent from serum leptin levels by a central mechanism involving α4β2* heteromeric nAChRs and stimulated increased expression of the anorexic peptide POMC. Whereas, increased NPY and AgRP expression could be a secondary response to reduction in weight gain. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Development of sex differences in the principal nucleus of the bed nucleus of the stria terminalis of mice: Role of Bax‐dependent cell death
Authors: Gotsiridze Tina , Kang Ningdong , Jacob Dena , Forger Nancy G.
Published: January 2007

Neuron number in the principal nucleus of the bed nucleus of the stria terminalis (BNSTp) is greater in adult male mice than in females. Deletion of the proapoptotic gene, Bax, increases the number of BNSTp cells in adulthood and eliminates the sex difference in cell number. Here, we map the ontogeny of sex differences in nuclear volume and cell number in the BNSTp of neonatal mice, and evaluate the role of cell death in the development of these differences. We find that BNSTp volume and cell number do not differ between male and female wild‐type mice on postnatal days P3, P5, or P7. Sex differences emerge after the first postnatal week and both measures are significantly greater in males than in females on P9 and P11. Cell death, assessed by TUNEL staining, was observed in the BNSTp of both sexes from P1–P8. Females had more TUNEL‐positive cells than males from approximately P3–P6, with the maximum number of dying cells observed on P5/P6. To test whether the Bax gene is required for sexually dimorphic cell death in the BNSTp, TUNEL cells were counted on P6 in Bax −/− mice and their Bax +/+ siblings. Bax gene deletion nearly abolished TUNEL‐positive cells in the BNSTp of both sexes. Together, these findings support the interpretation that the sex difference in BNSTp cell number seen in adulthood is due to Bax‐dependent, sexually dimorphic cell death during the first week of life. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Costorage of BDNF and neuropeptides within individual dense‐core vesicles in central and peripheral neurons
Authors: Salio C. , Averill S. , Priestley J.V. , Merighi A.
Published: January 2007

Some central and peripheral neurons synthesize brain‐derived neurotrophic factor (BDNF), and, after anterograde transport, release it at synapses. By immunocytochemistry, we examined, in rat and mouse, the subcellular localization of BDNF and BDNF/peptide coexistence, under normal conditions or after intrathecal infusion of nerve growth factor. In dorsal root ganglion neurons and afferent terminals, and in the parabrachial projection to amygdala, we show that BDNF is costored in individual dense‐core vesicles (DCVs) with the neuropeptides calcitonin gene‐related peptide (CGRP) and substance P. At both locations, nerve endings costoring all three peptides were fairly rare. Remarkably however, costorage occurred in a stoichiometric ratio of 0.7 BDNF:1 CGRP:1 substance P, and DCVs contained 31 (spinal cord) −36 (amygdala) times the amount of BDNF detected in agranular vesicles. This is the first direct demonstration in peripheral and central neurons from two different mammals, that a growth factor is selectively packaged together with neuropeptide transmitters within individual DCVs. It provides structural bases for differential release upon stimulation, and has important implications for understanding BDNF transmitter function. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007
Selective Palladium‐Catalysed ipso Arylation of α,α‐Disubstituted Benzo[b]thien‐2‐ylmethanols with Aryl Bromides using PCy3 as Ligand
Authors: Bíró A. Beatrix , Kotschy András
Published: January 2007

α,α‐Diphenylbenzo[b]thien‐2‐ylmethanol was treated with a series of aryl bromides in the presence of palladium(II) acetate and tricyclohexylphosphane to give the appropriate 2‐aryl‐benzo[b]thiophenes in good to excellent yield with concomitant formation of benzophenone. The reaction wassuccessfully extended to α,α‐diphenylbenzo[b]thien‐3‐ylmethanol, although in certain cases the transformation was biased by concurrent ortho arylation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Long‐term InHM simulations of hydrologic response and sediment transport for the R‐5 catchment
Authors: Heppner Christopher S. , Loague Keith , VanderKwaak Joel E.
Published: January 2007

The physics‐based model known as the Integrated Hydrology Model (InHM) is used to simulate continuous hydrologic response and event‐based sediment transport for the R‐5 catchment (Oklahoma, USA). For the simulations reported herein the R‐5 boundary‐value problem was refined, from that reported by Loague et al. (2005), to include (i) an improved conceptualization of the local hydrogeologic setting, (ii) a more accurate topographical representation of the catchment, (iii) improved boundary conditions for surface‐water outflow, subsurface‐water outflow and evapotranspiration, (iv) improved characterization of surface and subsurface hydraulic parameters and (v) improved initial conditions. The hydrologic‐response simulations were conducted in one‐year periods, for a total of six years. The sediment‐transport simulations were conducted for six selected events. The multi‐year water‐balance results from the hydrologic‐response simulations match the observed aggregate behavior of the catchment. Event hydrographs were generally simulated best for the larger events. Soil‐water content was over‐estimated during dry periods compared with the observed data. The sediment‐transport simulations were more successful in reproducing the total sediment mass than the peak sediment discharge rate. The results from the effort reported here reinforce the contention that comprehensive and detailed datasets are crucial for testing physics‐based hydrologic‐response models. Copyright © 2007 John Wiley & Sons, Ltd.
Hydrologic control of waveforms on small meandering rivers
Authors: Phillips R. T. J. , Robert A.
Published: January 2007

Small river channels within the Humber Basin of Southern Ontario exhibit irregular meandering patterns; however, contemporary river hydrology appears capable of controlling the scale of regular waveform development. Recent changes in river planform are assessed through a bi‐temporal comparison of channel planform using orthorectified aerial photography and statistical analysis of curvature series based on autocorrelation and spectral analysis. Calculated meander wavelengths are acceptable given traditional relationships between wavelength and mean annual flood discharge. It is also evident that changes in stream power are highly correlated with changes in the dominant wavelengths between channel reaches in this study. Gradual development of small scale waveforms following a rare hydrological and geomorphological event in 1954 further confirms that these forms can be attributed to the typical discharge regime. This paper argues that the scaling of wavelengths with discharge can be considered a strong factor controlling planform evolution on some small meandering river systems, despite manifest irregular planforms. Copyright © 2007 John Wiley & Sons, Ltd.
Stability analysis and simulation of a single‐phase voltage source UPS inverter with two‐stage cascade output filter
Authors: Faiz Jawad , Shahgholian Ghazanfar , Ehsan Mehdi
Published: January 2007

The primary role of an uninterruptible power supply (UPS) systems is to produce sinusoidal output voltage with minimum total harmonic distortion (THD) and fast dynamic response. This paper investigates the performance of two‐stage cascade output filter for single‐phase voltage source UPS inverter and it is compared with an LC output filter. The simulation result shows harmonic reduction of output voltage of the inverter due to using multiple‐filter. Both THD of the low output voltage and good voltage utilization can be achieved by the proposed filter scheme. The THD of the output voltage in various load condition are all less than 4%. A good agreement between the simulation and experimental results is achieved. Copyright © 2007 John Wiley & Sons, Ltd.
Soilscape and land‐use evolution related to drift sand movements since the bronze age in Eastern Jutland, Denmark
Authors: Mikkelsen Jari Hinsch , Langohr Roger , Macphail Richard I.
Published: January 2007

Quarry faces several kilometers long in the Glesborg area in Denmark show that Bronze Age farmers used a sustainable land‐use system. Despite nutrient‐poor soils, the Glesborg area was under a rotation system in which cropland alternated with grassland. Soil fertility was improved by the addition of household waste and probably also by locally obtained inorganic fertilizer. The soil surface was very stable, and local drift sand movement was limited. Toward the end of the Bronze Age, the landscape changed dramatically with the arrival of overwhelming amounts of drift sand, and farmsteads were abandoned. Subsequent land use on these poor fine sandy soils was no longer capable of maintaining a stable soil surface, and frequent erosion/sedimentation events of more local importance took place. The post‐Bronze Age landscape may have been mainly a shifting mosaic of heathland with some temporary arable fields and deflation/accumulation areas. This landscape persisted up to about 200 years ago, when afforestation programs started. © 2007 Wiley Periodicals, Inc.
Geoarchaeology of Tonga: Geotectonic and geomorphic controls
Authors: Dickinson William R. , Burley David V.
Published: January 2007

Ancient settlement patterns in central Tonga, at the southeastern limit of Lapita expansion into Remote Oceania ˜3 ka, were conditioned by island geomorphology as controlled by spatial geotectonic features and temporal changes in relative sea level on island coasts. Volcanic islands provided lithic resources, but human populations were concentrated on nonvolcanic forearc islands underlain by limestone covered by airfall tephra blankets that weathered to form rich agricultural soils and eroded to provide terrigenous sand for ceramic temper. The forearc islands lie along the Tonga platform, a linear tract of shoals uplifted diachronously by subduction of the buoyant Louisville Ridge at the Tonga Trench. Multiple transverse structural discontinuities break the forearc into discrete structural blocks, some tectonically stable during late Holocene time but others undergoing postuplift subsidence. Understanding the paleoenvironmental settings of Tongan archaeological sites requires reconstructing the contrasting geologic histories of different forearc island clusters. © 2007 Wiley Periodicals, Inc.
The G51S purine nucleoside phosphorylase polymorphism is associated with cognitive decline in Alzheimer's disease patients
Authors: Tumini Emanuela , Porcellini Elisa , Chiappelli Martina , Conti Chiara M. , Beraudi Alina , Poli Alessandro , Caciagli Francesco , Doyle Robert , Conti Pio , Licastro Federico
Published: January 2007

Alzheimer's disease (AD) is a polygenic and multifactorial complex disease, whose etiopathology is still unclear, however several genetic factors have shown to increase the risk of developing the disease. Purine nucleotides and nucleosides play an important role in the brain. Besides their role in neurotransmission and neuromodulation, they are involved in trophic factor release, apoptosis, and inflammatory responses. These mediators may also have a pivotal role in the control of neurodegenerative processes associated with AD. In this report the distribution of the exonic G/A single nucleotide polymorphism (SNP) in purine nucleoside phosphorylase (PNP) gene, resulting in the amino acid substitution serine to glycine at position 51 (G51S), was investigated in a large population of AD patients (n = 321) and non‐demented control (n = 208). The PNP polymorphism distribution was not different between patients and controls. The polymorphism distribution was also analyzed in AD patients stratified according to differential progressive rate of cognitive decline during a 2‐year follow‐up. An increased representation of the PNP AA genotype was observed in AD patients with fast cognitive deterioration in comparison with that from patients with slow deterioration rate. Our findings suggest that the G51S PNP polymorphism is associated with a faster rate of cognitive decline in AD patients, highlighting the important role of purine metabolism in the progression of this neurodegenerative disorder. Copyright © 2007 John Wiley & Sons, Ltd.
A new flow reactor for the treatment of polluted water with microwave and ultrasound
Authors: Cravotto Giancarlo , Di Carlo Stefano , Curini Massimo , Tumiatti Vander , Roggero Carlo
Published: January 2007

Microwave (MW) and high‐intensity ultrasound (US) provide innovative techniques for the degradation of persistent organic pollutants (POPs). When Fenton's reagent is used to treat industrial wastes, organic pollutants are degraded by highly reactive hydroxyl radicals (HO·) that can oxidize almost any organic compound to carbon dioxide and water. These reactions, when carried out under US or MW, are faster and much more efficient. The present work assesses the combined effect of US and MW using a new flow reactor developed in our laboratory. In this 5 L pilot reactor the liquid was pumped in parallel through a modified domestic MW oven and through a cell where it was irradiated with two US generators working at 20 and 300 kHz, while MW irradiation took place in a modified domestic oven. We studied the degradation of 2,4‐dibromophenol (0.1 g L−1 in water) by Fenton's reagent, assessing the contribution of each energy source to the overall effect, and found that MW and US‐300 kHz played the main role. A modest amount of oxidant (6 mL 30% H2O2 per 1 L of polluted water) sufficed to achieve complete degradation within 6 h, at which time organic compounds were no longer detectable. Even if no Fenton's reagent was added, about one half of the pollutant was degraded after 3 h irradiation. Copyright © 2007 Society of Chemical Industry
Catalytic synthesis of 1,6‐dicarbamate hexane over MgO/ZrO2
Authors: Li Fang , Wang Yanji , Xue Wei , Zhao Xinqiang
Published: January 2007

MgO/ZrO2 catalyst was prepared for the synthesis of 1,6‐dicarbamate hexane (HDC) using dimethyl carbonate (DMC) and 1,6‐diamine hexane (HDA) as raw materials. When the catalyst is calcined at 600 °C and MgO load is 6 wt%, the catalyst exhibits better activity. When the concentration of catalyst is 2 g (100 mL)−1 DMC, n(HDA):n(DMC) = 1:10, reaction time is 6 h under reflux temperature, and the yield of 1,6‐dicarbamate hexane is 53.1%. HDC yield decreases from 53.1% to 35.3% after MgO/ZrO2 being used for three times. The decrease in specific surface area may be attributed to deactivation of MgO/ZrO2. Copyright © 2007 Society of Chemical Industry