bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Contextual Effect of School Attachment on Young Adolescents’ Alcohol Use
Authors: Henry Kimberly L. , Slater Michael D. 
Published: January 2007

ABSTRACTBackground:  The school is a primary context for social interaction, cultivation of interpersonal skills, formation of peer groups, self‐expression, and development of self. Several studies have demonstrated that the social context of the school has important implications for determining the likelihood that an adolescent will follow a prosocial path through adolescence as opposed to becoming involved in delinquent behavior.Methods:  Using a data set of 4,216 youth in 32 middle schools and junior high schools across the United States, this paper examines the effect of a student’s own level of school attachment as well as the contextual level of school attachment (the normative level of school attachment in a school) on 5 alcohol‐related measures: recent use of alcohol, intention to use alcohol, normative beliefs about peer use of alcohol, attitudes toward alcohol use, and aspirations consistent with alcohol use.Results:  This study demonstrates that regardless of a student’s own level of school attachment, students who attend schools where the pupils overall tend to be well attached to school are less likely to use alcohol. In addition, they also have lower intentions to use alcohol, perceive that fewer of their peers at school use alcohol, and more strongly hold aspirations that are inconsistent with alcohol use.Conclusions:  Our findings, along with the findings of related studies, provide support for the hypothesis that improvement of school climate may result in less substance use among students.
Surveying Students About Controversial Subjects
Authors: Soronen Lisa E. 
Published: January 2007

ABSTRACTBackground:  Because of school districts’ interest in best serving the health needs of students, many choose to administer surveys addressing controversial topics. Administering such surveys in a voluntary and anonymous manner may help reduce conflict.Methods:  This is a review of 2 recent federal court of appeals decisions regarding surveying students about controversial topics.Results:  The 2 federal appellate cases examined whether mistakes and misperceptions were made when surveying students about controversial topics violated the US Constitution. Both courts wrestled with the tension between school and parental authority but ultimately ruled in favor of the defendant school district. In Fields v Palmdale School District, the Ninth Circuit stated that a parent’s right to control a child’s upbringing does not automatically supersede the school’s authority to control what goes on during school, including surveying students. In C.N. v Ridgewood Board of Education, the Third Circuit decided that a parent’s right to control a child’s upbringing extends into school, but surveying students about controversial topics does not violate that right. This article explains the significance of these cases and provides 10 suggestions school districts can follow to avoid the threat of litigation when surveying students about controversial topics.Conclusions:  School districts should ensure a student survey relates to the district’s overall educational goals. Likewise, the district should adequately inform parents of a survey’s contents, date of administration, and a parent’s ability to opt out. Schools should make sure a survey is truly voluntary and anonymous. Finally, schools should carefully follow local policy and state and federal laws that apply to surveying students, such as the federal Protection of Pupil Rights Amendment.
China's Changing Economic Structure and Implications for Regional Patterns of Trade, Production and Integration
Authors: Tan Kim Song , Khor Hoe Ee 
Published: January 2007

AbstractWithout intending to do so, China has in recent years played a major role in East Asia's economic integration. It has done so mainly through the production and supply chain networks it has spun across the region. This paper argues that given the developmental trends in the Chinese economy, the Chinese government should pursue a more active strategy towards a broader and more balanced economic integration with the region. The emergence of a multi‐track production structure, increased importance of domestic consumption and the services sector, together with faster integration of the domestic economy, will fundamentally change China's trade and investment relationships with the rest of East Asia and necessitate a review of China's economic integration strategy. The paper also argues that ASEAN can play a useful role in facilitating the region‐wide integration process.(Edited by Xiaoming Feng)
Anthropocene Geopolitics: Globalisation, Empire, Environment and Critique
Authors: Dalby Simon 
Published: January 2007

AbstractCritique is about challenging the taken for granted categories in scholarly and political discourse. Three aspects of contemporary politics at the biggest of scales are subject to critique here: the assumptions underlying the War on Terror, globalisation and the notion of environment. The global War on Terror is not really global, and might well be better understood by using imperial analogies from the past. Globalisation, once its implicit geographies are directly addressed, might be better understood as a matter of glurbanisation. Likewise earth system science, and its suggestion that human actions are now on such a large scale that we live in a new geological period, the Anthropocene, requires us to rethink assumptions of our living within an external environment. Taken together these criticisms of the taken for granted spatial categories of contemporary political life raise big questions for how geography is now understood and how we might teach it in the future. Such an analysis also suggests the continued importance of critique as an intellectual practice in the academy.
Preliminary Fan Design for a Silent Aircraft
Authors: Crichton Daniel , Xu Liping , Hall Cesare A. 
Published: January 2007

AbstractPreliminary fan design for a functionally silent aircraft has been performed with noise reduction as the primary goal. For such an aircraft the fan design must, in addition to delivering low cruise fuel burn, enable low jet and fan source noise during takeoff. This requires the fan to be operating at low pressure ratio and high efficiency during takeoff and, for conditions where the relative tip Mach number onto the fan is supersonic, ensuring the primary shock structure is ingested into the blade passage. To meet these requirements, flyover and cruise flow coefficients are matched using a variable area nozzle at the same time as delivering low takeoff FPR. This places the sideline operating point near the shoulder of the characteristic and fixes the top of climb and cruise fan pressure ratios. For a 4-engine, 250pax, 4000nm silent aircraft this approach leads to a top of climb FPR of 1.45, requiring a 39% increase in nozzle area at takeoff. A fan rotor has been designed for this cycle with 20 blades, low tip loading during takeoff, and a 350m∕s top of climb tip speed.
Diminished Ciprofloxacin-Induced Chondrotoxicity by Supplementation with Magnesium and Vitamin E in Immature Rats
Authors: Pfister Kerstin , Mazur Dago , Vormann Jürgen , Stahlmann Ralf 
Published: January 2007

ABSTRACT

Quinolone-induced chondrotoxicity in juvenile rats and multiple other species has been demonstrated previously. Identical damages can be induced in immature rats by feeding them a magnesium-deficient diet. The objective of the present study was to investigate whether, in reverse, oral supplementation with magnesium, vitamin E, or both can diminish the typical quinolone-induced arthropathy in juvenile Wistar rats. Four groups of 12 (6 male, 6 female) 24-day-old Wistar rats were each fed either normal feed (group A), a vitamin E-enriched diet (group B), a magnesium-enriched diet (group C), or a diet enriched with both vitamin E and magnesium (group D) for 10 days. All rats received two subcutaneous ciprofloxacin doses of 600 mg/kg of body weight on postnatal day 32. Two days later, the rats were sacrificed and cartilage samples from knee joints were examined under a light microscope for the presence of typical quinolone-induced joint cartilage lesions. In addition, magnesium, calcium, and vitamin E concentrations in cartilage and plasma were determined. In the samples from rats fed a normal diet (group A), 17 quinolone-induced joint cartilage lesions were observed. In groups fed an enriched diet, the incidence of specific lesions (
n
) was significantly lower: group B,
n
= 10 (41% reduction compared to the incidence for group A;
P
< 0.05); group C,
n
= 6 (65% reduction;
P
< 0.01); and group D,
n
= 3 (82% reduction;
P
< 0.01). In comparison to the standard diet, diets with magnesium and vitamin E supplementation resulted in significantly higher magnesium and vitamin E concentrations in plasma and articular cartilage. Supplementation with magnesium and vitamin E alone or in combination may relevantly diminish joint cartilage lesions induced by quinolones in immature rats, with an additive effect of combined supplementation. The data further support the proposed pathomechanism of quinolone-induced arthropathy and the crucial role of magnesium in immature joint cartilage.
Independent Evolution of Pyrimethamine Resistance in
Plasmodium falciparum
Isolates in Melanesia
Authors: Mita Toshihiro , Tanabe Kazuyuki , Takahashi Nobuyuki , Tsukahara Takahiro , Eto Hideaki , Dysoley Lek , Ohmae Hiroshi , Kita Kiyoshi , Krudsood Srivicha , Looareesuwan Sornchai , Kaneko Akira , Björkman Anders , Kobayakawa Takatoshi 
Published: January 2007

ABSTRACT

Pyrimethamine resistance in
Plasmodium falciparum
has previously been shown to have emerged once in Southeast Asia, from where it spread to Africa. Pyrimethamine resistance in this parasite is known to be conferred by mutations in the gene encoding dihydrofolate reductase (
dhfr
). We have analyzed polymorphisms in
dhfr
as well as microsatellite haplotypes flanking this gene in a total of 285 isolates from different regions of Melanesia (Papua New Guinea, Vanuatu, and the Solomon Islands) and Southeast Asia (Thailand and Cambodia). Nearly all isolates (92%) in Melanesia were shown to carry a
dhfr
double mutation (CN

RN

I [underlining indicates the mutation]) at positions 50, 51, 59, 108, and 164, whereas 98% of Southeast Asian isolates were either triple (C

IRN

I) or quadruple (C

IRNL

) mutants. Microsatellite analysis revealed two distinct lineages of
dhfr
double mutants in Melanesia. One lineage had the same microsatellite haplotype as that previously reported for Southeast Asia and Africa, suggesting the spread of this allele to Melanesia from Southeast Asia. The other lineage had a unique, previously undescribed microsatellite haplotype, indicative of the de novo emergence of pyrimethamine resistance in Melanesia.
Antimicrobial Activities of Ceragenins against Clinical Isolates of Resistant
Staphylococcus aureus
Authors: Chin Judy N. , Rybak Michael J. , Cheung Chrissy M. , Savage Paul B. 
Published: January 2007

ABSTRACT

The rise in the rates of glycopeptide resistance among
Staphylococcus aureus
isolates is concerning and underscores the need for the development of novel potent compounds. Ceragenins CSA-8 and CSA-13, cationic steroid molecules that mimic endogenous antimicrobial peptides, have previously been demonstrated to possess broad-spectrum activities against multidrug-resistant bacteria. We examined the activities of CSA-8 and CSA-13 against clinical isolates of vancomycin-intermediate
S. aureus
(VISA), heterogeneous vancomycin-intermediate
S. aureus
(hVISA), as well as vancomycin-resistant
S. aureus
(VRSA) and compared them to those of daptomycin, linezolid, and vancomycin by susceptibility testing and killing curve analysis. We also examined CSA-13 for its concentration-dependent activity, inoculum effect, postantibiotic effect (PAE), and synergy in combination with various antimicrobials. Overall, the MICs and minimal bactericidal concentrations of CSA-13 were fourfold lower than those of CSA-8. Time-kill curve analysis of the VRSA, VISA, and hVISA clinical isolates demonstrated concentration-dependent bactericidal killing. An inoculum effect was also observed when a higher starting bacterial density was used, with the time required to achieve 99.9% killing reaching 1 h with a 6-log
10
-CFU/ml starting inoculum, whereas it was ≥24 h with a 8- to 9-log
10
-CFU/ml starting inoculum with 10× the MIC (
P
≤ 0.001). A concentration-dependent PAE was demonstrated with CSA-13, nearly doubling from 2× to 4× the MIC (
P
= 0.03). With respect to the CSA-13 antimicrobial combinations, time-kill curve analysis showed no difference in the log
10
CFU/ml at 24 h for the majority of the organisms tested. However, early synergy at 4 to 8 h was detected against the VRSA Pennsylvania strain (2002) when CSA-13 was tested in combination with gentamicin, while early additivity was demonstrated against all of the other organisms.
α-Tubulin Minichromosome Promoters in the Stichotrichous Ciliate
Stylonychia lemnae
Authors: Skovorodkin Ilya , Pimenov Alexander , Raykhel Irina , Schimanski Bernd , Ammermann Dieter , Günzl Arthur 
Published: January 2007

ABSTRACT

Ciliated protists are model organisms for a number of molecular phenomena including telomerase function, self-splicing introns, and an RNA interference-related mechanism in programmed DNA elimination. Despite this relevance, our knowledge about promoters and transcriptional regulation in these organisms is very limited. The macronuclear genome of stichotrichous ciliates consists of minichromosomes which typically encode a single gene. The 5′ nontranscribed spacers are usually no longer than 400 bp and highly suitable for promoter characterizations. We used microinjection of two artificial and differently tagged α1 tubulin minichromosomes into the macronucleus of
Stylonychia lemnae
as a means to characterize in detail the corresponding promoter. Clonal cell lines that stably maintained both minichromosomes were generated, enabling comparative expression analysis by primer extension assays. Deletion and block substitution mutations of one of the minichromosomes revealed a TATA-like element, a putative initiator element, and two distinct upstream sequence elements (USEs). Determination of transcription initiation sites and a sequence alignment indicated that both TATA-like and initiator elements are conserved components of
S. lemnae
minichromosomes, whereas the USEs appear to be specific for the α1 tubulin minichromosome. The α2 tubulin minichromosome promoter is very short, comprising the two proximal elements but not the USEs. Despite the latter finding, up-regulation of α-tubulin expression in cells treated with concanavalin A activated the α2 but not the α1 tubulin promoter. These results therefore show that gene expression regulation in
S. lemnae
occurs at the level of transcription initiation on the basis of structurally different promoters.
Rat Model of Polymicrobial Infection, Immunity, and Alveolar Bone Resorption in Periodontal Disease
Authors: Kesavalu Lakshmyya , Sathishkumar Sabapathi , Bakthavatchalu Vasudevan , Matthews Chad , Dawson Dolph , Steffen Michelle , Ebersole Jeffrey L. 
Published: January 2007

ABSTRACT

One of the predominant polymicrobial infections of humans is expressed clinically as periodontal disease.
Porphyromonas gingivalis
,
Treponema denticola
, and
Tannerella forsythia
have been strongly implicated as members of a pathogenic consortium in the etiology of adult periodontitis. In this study we hypothesized that
P. gingivalis
,
T. denticola
, and
T. forsythia
are synergistic in terms of virulence potential and induce chronic periodontal inflammation that leads to alveolar bone resorption in a polymicrobial infection in rats. Groups of rats were infected with either
P. gingivalis
,
T. denticola
, or
T. forsythia
in monomicrobial infections or with all three species in polymicrobial oral infections with or without
Fusobacterium nucleatum
. PCR analyses of oral microbial samples demonstrated that rats infected with one bacterium were orally colonized by each of the bacteria during the study interval, and increased serum immunoglobulin G (IgG) antibody levels substantiated the interaction of the host with the infecting bacteria. PCR analyses of the rats with polymicrobial infections demonstrated that most rats were infected with
P. gingivalis
,
T. denticola
, and
T. forsythia
as a consortium. Furthermore, all rats exhibited a significant increase in the level of IgG antibody to the polymicrobial consortium. Radiographic measurement of alveolar bone resorption showed that rats infected with the polymicrobial consortium with or without
F. nucleatum
exhibited significantly increased alveolar bone resorption compared to the resorption in uninfected control rats, as well as the resorption in rats infected with one of the microbes. These results documented that
P. gingivalis
,
T. denticola
, and
T. forsythia
not only exist as a consortium that is associated with chronic periodontitis but also exhibit synergistic virulence resulting in the immunoinflammatory bone resorption characteristic of periodontitis.
Interleukin-12 Promotes Gamma Interferon-Dependent Neutrophil Recruitment in the Lung and Improves Protection against Respiratory
Streptococcus pneumoniae
Infection
Authors: Sun Keer , Salmon Sharon L. , Lotz Steven A. , Metzger Dennis W. 
Published: January 2007

ABSTRACT

The ability of exogenous interleukin-12 (IL-12) to elicit protective innate immune responses against the extracellular pathogen
Streptococcus pneumoniae
was tested by infecting BALB/c mice intranasally (i.n.) with
S. pneumoniae
after i.n. administration of IL-12. It was found that administration of IL-12 resulted in lower bacterial burdens in the infected mice and significantly improved survival rates. All IL-12-treated mice contained higher levels of pulmonary gamma interferon (IFN-γ) after infection and significantly more neutrophils than infected mice not treated with IL-12. IFN-γ was found to be essential for IL-12-induced resistance and for neutrophil influx into the lungs, and the observed changes correlated with increased levels of the IL-8 homologue keratinocyte-derived chemokine (KC). In addition, in vitro tumor necrosis factor alpha (TNF-α) production by alveolar macrophages stimulated with heat-killed pneumococci was enhanced by IFN-γ, and TNF-α in turn could enhance production of KC by lung cells. Finally, IL-12-induced protection was dependent upon the presence of neutrophils and the KC receptor CXCR2. Taken together, the results indicate that exogenous IL-12 can improve innate defense in the lung against
S. pneumoniae
by inducing IFN-γ production, which in turn enhances chemokine expression, and promotes pulmonary neutrophil recruitment into the infected lung. The findings show that IL-12 and IFN-γ can mediate a protective effect against respiratory infection caused by extracellular bacterial pathogens.
Resistance ofFrancisella tularensisStrains against Reactive Nitrogen and Oxygen Species with Special Reference to the Role of KatG
Authors: Lindgren Helena , Shen Hua , Zingmark Carl , Golovliov Igor , Conlan Wayne , Sjöstedt Anders 
Published: January 2007

ABSTRACTFrancisella tularensisis a facultative intracellular bacterial pathogen capable of proliferating within host macrophages. The mechanisms that explain the differences in virulence between various strains of the species are not well characterized. In the present study, we show that both attenuated (strain LVS) and virulent (strains FSC200 and SCHU S4) strains of the pathogen replicate at similar rates in resting murine peritoneal exudate cells (PEC). However, when PEC were activated by exposure to gamma interferon (IFN-γ), they killed LVS more rapidly than virulent strains of the pathogen. Addition ofNG-monomethyl-l-arginine, an inhibitor of inducible nitric oxide synthase, to IFN-γ-treated PEC, completely inhibited killing of the virulent strains, whereas it only partially blocked the killing of LVS. Similarly, in a cell-free system, SCHU S4 and FSC200 were more resistant to killing by H2O2and ONOO−thanF. tularensisLVS. Catalase encoded bykatGis a bacterial factor that can detoxify bactericidal compounds such as H2O2and ONOO−. To investigate its contribution to the virulence ofF. tularensis,katGdeletion-containing mutants of SCHU S4 and LVS were generated. Both mutants demonstrated enhanced susceptibility to H2O2in vitro but replicated as effectively as the parental strains in unstimulated PEC. In mice, LVS-ΔkatGwas significantly attenuated compared to LVS whereas SCHU S4-ΔkatG, despite slower replication, killed mice as quickly as SCHU S4. This implies that clinical strains of the pathogen havekatG-independent mechanisms to combat the antimicrobial effects exerted by H2O2and ONOO−, the loss of which could have contributed to the attenuation of LVS.
Dietary protein for athletes: from requirements to metabolic advantage
Authors: Phillips Stuart M. 
Published: January 2007

The Dietary Reference Intakes (DRI) specify that the requirement for dietary protein for all individuals aged 19 y and older is 0.8 g protein·kg–1·d–1. This Recommended Dietary Allowance (RDA) is cited as adequate for all persons. This amount of protein would be considered by many athletes as the amount to be consumed in a single meal, particularly for strength-training athletes. There does exist, however, published data to suggest that individuals habitually performing resistance and (or) endurance exercise require more protein than their sedentary counterparts. The RDA values for protein are clearly set at “…the level of protein judged to be adequate... to meet the known nutrient needs for practically all healthy people…”. The RDA covers protein losses with margins for inter-individual variability and protein quality; the notion of consumption of excess protein above these levels to cover increased needs owing to physical activity is not, however, given any credence. Notwithstanding, diet programs (i.e., energy restriction) espousing the virtue of high protein enjoy continued popularity. A number of well-controlled studies are now published in which “higher” protein diets have been shown to be effective in promoting weight reduction, particularly fat loss. The term “higher” refers to a diet that has people consuming more than the general populations’ average intake of ~15% of energy from protein, e.g., as much as 30%–35%, which is within an Acceptable Macronutrient Distribution Range (AMDR) as laid out in the DRIs. Of relevance to athletes and those in clinical practice is the fact that higher protein diets have quite consistently been shown to result in greater weight loss, greater fat loss, and preservation of lean mass as compared with “lower” protein diets. A framework for understanding dietary protein intake within the context of weight loss and athletic performance is laid out.