bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of nonuniform resistivity in Petschek reconnection
Authors: Baty H. , Priest E. R. , Forbes T. G.
Published: February 2006

The controversial topic of the existence of a Petschek solution in steady-state magnetic reconnection for a uniform resistivity is investigated, by using two-dimensional time-dependent magnetohydrodynamic simulations. A classical localized nonuniform resistivity with a profile that is exponentially decreasing from the X point is helpful to set up the Petschek solution as a first step, using a procedure with overspecified boundary conditions. The response to changing the resistivity profile in various ways is then studied. It is found that a Petschek configuration is obtained when a quasiuniform resistivity is adopted. This is the case if the resistivity profile exhibits a weak negative gradient close to the X point, which dominates an inherent numerical contribution; otherwise an instability develops which disrupts the configuration. A truly uniform resistivity is probably only marginally stable. Finally, the validity of the arguments given by Kulsrud [Earth Planets Space 53, 417 (2001)] about the “incorrectness” of Petschek’s original model is discussed.
Quasielastic neutron scattering investigation of the pressure dependence of molecular motions in liquid water
Authors: Cunsolo A. , Orecchini A. , Petrillo C. , Sacchetti F.
Published: February 2006

We report on a high-resolution, high-statistics, quasielastic neutron scattering (QENS) experiment on liquid water, aimed at accurately measuring the pressure dependence of the single-particle dynamic response function at low wave vector transfers, namely, from 0.26 to 1.32Å−1. High-pressure QENS data were collected along the T=268K isothermal path over the rather extended pressure range of 80 up to 350 MPa, a thermodynamic region so far unexplored by this microscopic technique. The analysis of the measured line shapes enabled us to draw a consistent picture of the wave vector and pressure dependences of the diffusion mechanisms in liquid water, against which the most recent models for water dynamics can be checked. In close similarity with the case of supercooled water, the relaxing-cage model was found to provide a quantitatively more accurate description of the molecular motions and their pressure evolution in liquid water.
Frequency tunability of terahertz photonic transmitters
Authors: Kao Tzeng-Fu , Chang Hsu-Hao , Chen Li-Jin , Lu Ja-Yu , Liu An-Shyi , Yu Yi-Chun , Wu Ruey-Beei , Liu Wei-Sheng , Chyi Jen-Inn , Sun Chi-Kuang
Published: February 2006

In this study we investigated the frequency tunability of an edge-coupled membrane photonic transmitter. Its frequency tunability was found to be determined, not only by the radiation loss of the device and antenna pattern, but also by the frequency response of the photodetector. With a properly designed device pattern with a slot dipole antenna, which is known to have a strong resonant peak, both high-power conversion efficiency and a broadband response can be achieved. A wide frequency tuning range from <100GHz up to 1.1THz is demonstrated from a single terahertz photonic transmitter. Combined with coherent-controlled quasicontinuous-wave optical excitation, this optoelectronic-based device also exhibits a record-high light-THz power-conversion efficiency of 0.33%.
Collinear dual-color laser emission from a microfluidic dye laser
Authors: Kou Q. , Yesilyurt I. , Chen Y.
Published: February 2006

Collinear dual-color laser emission on a chip is obtained from a liquid dye mixture flowing through an optical microcavity. Soft lithography has been used to fabricate the microfluidic channels and integrate the optical resonator. The laser cavity, of nanoliter volume, is made of two parallel gold mirrors coated on the end faces of optical fibers and integrated into a polydimethylsiloxane chip. Such a design allows a simple but efficient coupling of the laser emission with an optical fiber. The amplification medium is composed of rhodamine 6G and sulforhodamine, dissolved in a common ethanol solution. When the dye mixture is optically pumped by a pulsed and frequency-doubled Nd:YAG laser, simultaneous laser emission at wavelengths 559nm and 597nm is observed, showing yellow and red colors with a complete spatial overlap within the single output beam. Moreover, the overall laser efficiency for the dye mixture system is significantly increased compared to that for the individual dyes.
Complementary carbon nanotube-gated carbon nanotube thin-film transistor
Authors: Chen Bae-Horng , Lin Horng-Chih , Huang Tiao-Yuan , Wei Jeng-Hua , Wang Hung-Hsiang , Tsai Ming-Jinn , Chao Tien Sheng
Published: February 2006

We introduce, a complementary carbon nanotube (CNT)-gated CNT thin-film field effect transistor (FET). By using two perpendicularly crossed single-wall CNT (SWNT) bundles as the gate and the channel interchangeably, a sub-50nm complementary CNT-FET is demonstrated. It is found that the new CNT-FET shows acceptable FET characteristics by interchanging the roles of the gate and the channel. The unique dual functionality of the device will open up a new possibility and flexibility in the design of future complementary CNT electronic circuits.
Lithium fluoride nanowires via vapor-liquid-solid growth
Authors: Jiang C. B. , Wu B. , Zhang Z. Q. , Lu L. , Li S. X. , Mao S. X.
Published: February 2006

Lithium fluoride (LiF) nanowires with diameter of 100nm–500nm and length of tens of microns were synthesized via vapor-liquid-solid growth. Cubic-structured single-crystalline LiF nanowires grew along the ⟨001⟩ and ⟨110⟩ crystallographic directions, respectively. The growth of the LiF nanowires was proposed by the catalysis of Zn droplets decomposed from the ZnO. The LiF nanowire could be a potential candidate for the room-temperature tunable color center nanolaser.
Learning from the historical failure of farm management models to aid management practice. Part 2. Three systems approaches
Authors: McCown R. L. , Parton K. A.
Published: February 2006

Part 1 analysed the difficulties experienced in the field of academic Farm Management in making complex theoretical models relevant to farming. This paper highlights the important connections developed between the field of Farm Management economics and 3 key ‘systems’ ideas and tools in agricultural science in response to difficulties and opportunities. The first systems approach reviewed is the 20-year experiment by agricultural economists in using crop and animal production simulation models in management analyses. The second systems approach reviewed is Farming Systems Research (FSR), an approach characterised by on-farm experimentation with a management orientation. Many pioneers of FSR were Farm Management economists disenchanted by the inapplicability of economic theory to farm management. The FSR that emerged is interpreted as a scion of the early era of Farm Management prior to the coup by economics theorists in the 1940s. A third systems approach reviewed is a ‘soft’ intervention to facilitate farmer learning. Although evolving from FSR, this approach has surprising similarities to the ‘goal adjusting’ consulting performed by the legendary Australian Farm Management consultant cum academic, Jack Makeham. The paper concludes with discussion of a recent innovation that combines these 3 approaches. It uses a soft intervention approach that features farmers shaping their goals and expectations by ‘experimenting’ in a local, but virtual, environment provided by simulation of the production system using ‘hard’ models.
Inheritance of thermo-photoperiod sensitive male sterility in wheat
Authors: Guo Rui-Xing , Sun Dong-Fa , Cheng Xun-Dong , Rong De-Fu , Li Chengdao
Published: February 2006

The fertility of a wheat male sterile line 337S was investigated in 4 consecutive years with 18 different sowing dates. Line 337S showed high sterility under both short daylength/low temperature and long daylength/high temperature during ear development. It has 2 time windows to be used as a male sterile line for hybrid seed production. Its fertility rate can be >50% with suitable sowing time; thus, it can be self-maintained as a male sterile line. Line 337S was reciprocally crossed with 7 common wheat varieties and the fertility of their F1, F2, and BC1 hybrids was investigated at different sowing dates. The results showed that recessive nuclear genes controlled male sterility in 337S and no cytoplasmic effect was observed. All common wheat varieties were able to restore its fertility. The male sterility was controlled by a pair of recessive genes under short daylength/low temperature, but was governed by 2 pairs of recessive genes under long daylength/high temperature. This novel male sterile line provides a new tool for using heterosis in wheat.
Protein S stimulates inhibition of the tissue factor pathway by tissue factor pathway inhibitor
Authors: Hackeng Tilman M. , Seré Kristin M. , Tans Guido , Rosing Jan
Published: February 2006

Tissue factor (TF) plays an important role in hemostasis, inflammation, angiogenesis, and the pathophysiology of atherosclerosis and cancer. In this article we uncover a mechanism in which protein S, which is well known as the cofactor of activated protein C, specifically inhibits TF activity by promoting the interaction between full-length TF pathway inhibitor (TFPI) and factor Xa (FXa). The stimulatory effect of protein S on FXa inhibition by TFPI is caused by a 10-fold reduction of the

K
i

of the FXa/TFPI complex, which decreased from 4.4 nM in the absence of protein S to 0.5 nM in the presence of protein S. This decrease in

K
i

not only results in an acceleration of the feedback inhibition of the TF-mediated coagulation pathway, but it also brings the TFPI concentration necessary for effective FXa inhibition well within range of the concentration of TFPI in plasma. This mechanism changes the concept of regulation of TF-induced thrombin formation in plasma and demonstrates that protein S and TFPI act in concert in the inhibition of TF activity. Our data suggest that protein S deficiency not only increases the risk of thrombosis by impairing the protein C system but also by reducing the ability of TFPI to down-regulate the extrinsic coagulation pathway.
Identification of a domain in
Yersinia
virulence factor YadA that is crucial for extracellular matrix-specific cell adhesion and uptake
Authors: Heise Tanja , Dersch Petra
Published: February 2006

For many pathogens, cell adhesion factors are critical virulence determinants. Enteropathogenic
Yersinia
species express the afimbrial adhesin YadA, the prototype of a class of homotrimeric outer membrane adhesins, which mediates adherence to host cells by binding to extracellular matrix components. In this study, we demonstrate that different pathogenic functions are attributable to highly homologous YadA proteins. YadA of
Yersinia pseudotuberculosis
(YadA

pstb

) and
Yersinia enterocolitica
(YadA

ent

) exhibit fundamental differences in their specificity of extracellular matrix substrate binding, they cause dissimilar bacterial aggregation behaviors, and YadA

pstb

, but not YadA

ent

, promotes efficient uptake into human cells. Evidence is presented here that a unique N-terminal amino acid sequence of YadA

pstb

, which is absent in YadA

ent

, acts as an “uptake domain” by mediating tight binding to fibronectin bound on α
5
β
1
integrin receptors, which are crucial for initiating the entry process. Deleting this motif in YadA

pstb

generated all features of the YadA

ent

protein, i.e., the molecule lost its adhesiveness to fibronectin and its invasiveness, but gained adhesion potential to collagen and laminin. Loss of the “uptake region” also attenuated host tissue colonization by
Y. pseudotuberculosis
during oral infections of mice, demonstrating that this motif plays a crucial role in defining pathogen–host cell interaction and pathogenesis. We conclude that even small variations in adhesion factors can provoke major differences in the virulence properties of related pathogens.
Shaping up the protein folding funnel by local interaction: Lesson from a structure prediction study
Authors: Chikenji George , Fujitsuka Yoshimi , Takada Shoji
Published: February 2006

Predicting protein tertiary structure by folding-like simulations is one of the most stringent tests of how much we understand the principle of protein folding. Currently, the most successful method for folding-based structure prediction is the fragment assembly (FA) method. Here, we address why the FA method is so successful and its lesson for the folding problem. To do so, using the FA method, we designed a structure prediction test of “chimera proteins.” In the chimera proteins, local structural preference is specific to the target sequences, whereas nonlocal interactions are only sequence-independent compaction forces. We find that these chimera proteins can find the native folds of the intact sequences with high probability indicating dominant roles of the local interactions. We further explore roles of local structural preference by exact calculation of the HP lattice model of proteins. From these results, we suggest principles of protein folding: For small proteins, compact structures that are fully compatible with local structural preference are few, one of which is the native fold. These local biases shape up the funnel-like energy landscape.
Self-assembly of synthetic collagen triple helices
Authors: Kotch Frank W. , Raines Ronald T.
Published: February 2006

Collagen is the most abundant protein in animals and the major component of connective tissues. Although collagen isolated from natural sources has long served as the basis for some biomaterials, natural collagen is difficult to modify and can engender pathogenic and immunological side effects. Collagen comprises a helix of three strands. Triple helices derived from synthetic peptides are much shorter (<10 nm) than natural collagen (≈300 nm), limiting their utility. Here, we describe the synthesis of short collagen fragments in which the three strands are held in a staggered array by disulfide bonds. Data from CD spectroscopy, dynamic light scattering, analytical ultracentrifugation, atomic force microscopy, and transmission electron microscopy indicate that these “sticky-ended” fragments self-assemble via intermolecular triple-helix formation. The resulting fibrils resemble natural collagen, and some are longer (>400 nm) than any known collagen. We anticipate that our self-assembly strategy can provide synthetic collagen-mimetic materials for a variety of applications.
Proteinase 3 is an IL-32 binding protein
Authors: Novick Daniela , Rubinstein Menachem , Azam Tania , Rabinkov Aharon , Dinarello Charles A. , Kim Soo-Hyun
Published: February 2006

IL-32, a recently discovered proinflammatory cytokine with four isoforms, induces IL-1β, TNF-α, IL-6, and chemokines. Here, we used ligand (IL-32α) affinity chromatography in an attempt to isolate an IL-32α soluble receptor or binding protein. Recombinant IL-32α was covalently immobilized on agarose, and preparations of concentrated crude human urinary proteins were applied for chromatographic separation. A specific 30-kDa protein eluted from the column during acid washing and was identified by mass spectrometry as proteinase 3 (PR3) and confirmed by N-terminal microsequencing. PR3, a neutrophil granule serine protease, exists in a soluble or membrane form and is the major autoantigen for autoantibodies in the systemic vasculitic disease, Wegener's granulomatosis. The affinity of IL-32α to PR3 was determined by surface plasmon resonance. The dissociation constants were 2.65 ± 0.4 nM for urinary PR3 and 1.2 ± 0.05 nM for neutrophil-derived PR3. However, irreversible inactivation of PR3 enzymatic activity did not significantly change binding to the cytokine. Nevertheless, limited cleavage of IL-32 yielded products consistent with PR3 enzyme activity. Moreover, after limited cleavage by PR3, IL-32α was more active than intact IL-32α in inducing macrophage inflammatory protein-2 in mouse macrophages and IL-8 in human peripheral blood mononuclear cells. We suggest that PR3 is a specific IL-32α binding protein, independent of its enzymatic activity. However, limited cleavage of IL-32α by PR3 enhances activities of the cytokine. Therefore, specific inhibition of PR3 activity to process IL-32 or neutralization of IL-32 by inactive PR3 or its fragments may reduce the consequences of IL-32 in immune regulated diseases.
Reversal to cisplatin sensitivity in recurrent human ovarian cancer cells by NCX-4016, a nitro derivative of aspirin
Authors: Bratasz Anna , Weir Nathan M. , Parinandi Narasimham L. , Zweier Jay L. , Sridhar Rajagopalan , Ignarro Louis J. , Kuppusamy Periannan
Published: February 2006

Ovarian cancer is a gynecological malignancy that is commonly treated by cytoreductive surgery followed by cisplatin treatment. However, the cisplatin treatment, although successful initially, is not effective in the treatment of the recurrent disease that invariably surfaces within a few months of the initial treatment. The refractory behavior is attributed to the increased levels of cellular thiols apparently caused by the cisplatin treatment. This observation prompted us to choose a cytotoxic drug whose activity is potentiated by cellular thiols with enhanced specificity toward the thiol-rich cisplatin-resistant cells. We used NCX-4016 [2-(acetyloxy)benzoic acid 3-(nitrooxymethyl)phenyl ester], a derivative of aspirin containing a nitro group that releases nitric oxide in a sustained fashion for several hours in cells andin vivo, and we studied its cytotoxic efficacy against human ovarian cancer cells (HOCCs). Cisplatin-sensitive and cisplatin-resistant (CR) HOCCs were treated with 100 μM NCX-4016 for 6 h, and/or 0.5 μg/ml cisplatin for 1 h and assayed for clonogenecity. NCX-4016 significantly reduced the surviving fractions of cisplatin-sensitive (63 ± 6%) and CR (70 ± 10%) HOCCs. NCX-4016 also caused a 50% reduction in the levels of cellular glutathione in CR HOCCs. Treatment of cells with NCX-4016 followed by cisplatin showed a significantly greater extent of toxicity when compared with treatment of cells with NCX-4016 or cisplatin alone. In conclusion, this study showed that NCX-4016 is a potential inhibitor of the proliferation of CR HOCCs and thus might specifically kill cisplatin-refractory cancer cells in patients with recurrent ovarian cancer.
Common dynamical signatures of familial amyotrophic lateral sclerosis-associated structurally diverse Cu, Zn superoxide dismutase mutants
Authors: Khare Sagar D. , Dokholyan Nikolay V.
Published: February 2006

More than 100 structurally diverse point mutations leading to aggregation in the dimeric enzyme Cu, Zn superoxide dismutase (SOD1) are implicated in familial amyotrophic lateral sclerosis (FALS). Although SOD1 dimer dissociation is a known requirement for its aggregation, the common structural basis for diverse FALS mutations resulting in aggregation is not fully understood. In molecular dynamics simulations of wild-type SOD1 and three structurally diverse FALS mutants (A4V, G37R, and H46R), we find that a common effect of mutations on SOD1 dimer is the mutation-induced disruption of dynamic coupling between monomers. In the wild-type dimer, the principal coupled motion corresponds to a “breathing motion” of the monomers around an axis parallel to the dimer interface, and an opening–closing motion of the distal metal-binding loops. These coupled motions are disrupted in all three mutants independent of the mutation location. Loss of coupled motions in mutant dimers occurs with increased disruption of a key stabilizing structural element (the β-plug) leading to the de-protection of edge strands. To rationalize disruption of coupling, which is independent of the effect of the mutation on global SOD1 stability, we analyze the residue–residue interaction network formed in SOD1. We find that the dimer interface and metal-binding loops, both involved in coupled motions, are regions of high connectivity in the network. Our results suggest that independent of the effect on protein stability, altered protein dynamics, due to long-range communication within its structure, may underlie the aggregation of mutant SOD1 in FALS.
A cerebellar model for predictive motor control tested in a brain-based device
Authors: McKinstry Jeffrey L. , Edelman Gerald M. , Krichmar Jeffrey L.
Published: February 2006

The cerebellum is known to be critical for accurate adaptive
control and motor learning. We propose here a mechanism by which the
cerebellum may replace reflex control with predictive control. This
mechanism is embedded in a learning rule (the delayed eligibility
trace rule) in which synapses onto a Purkinje cell or onto a cell in
the deep cerebellar nuclei become eligible for plasticity only after a
fixed delay from the onset of suprathreshold presynaptic activity. To
investigate the proposal that the cerebellum is a general-purpose
predictive controller guided by a delayed eligibility trace rule, a
computer model based on the anatomy and dynamics of the cerebellum was
constructed. It contained components simulating cerebellar cortex and
deep cerebellar nuclei, and it received input from a middle temporal
visual area and the inferior olive. The model was incorporated in a
real-world brain-based device (BBD) built on a Segway robotic platform
that learned to traverse curved paths. The BBD learned which visual
motion cues predicted impending collisions and used this experience to
avoid path boundaries. During learning, the BBD adapted its velocity
and turning rate to successfully traverse various curved paths. By
examining neuronal activity and synaptic changes during this behavior,
we found that the cerebellar circuit selectively responded to motion
cues in specific receptive fields of simulated middle temporal visual
areas. The system described here prompts several hypotheses about the
relationship between perception and motor control and may be useful in
the development of general-purpose motor learning systems for
machines.
Alternatively spliced neuronal nitric oxide synthase mediates penile erection
Authors: Hurt K. Joseph , Sezen Sena F. , Champion Hunter C. , Crone Julie K. , Palese Michael A. , Huang Paul L. , Sawa Akira , Luo Xiaojiang , Musicki Biljana , Snyder Solomon H. , Burnett Arthur L.
Published: February 2006

A key role for nitric oxide (NO) in penile erection is well established, but the relative roles of the neuronal NO synthase (nNOS) versus endothelial forms of NOS are not clear. nNOS- and endothelial NOS-deficient mice maintain erectile function and reproductive capacity, questioning the importance of NO. Alternatively, residual NO produced by shorter transcripts in the nNOS
−/−
animals might suffice for normal physiologic function. We show that the β splice variant of nNOS elicits normal erection despite a decrease in stimulus-response characteristics and a 5-fold increased sensitivity to the NOS inhibitor,
l
-NAME. Residual nNOSβ generates only 10% of the normal NO level
in vitro
but produces citrulline and diaphorase staining reflecting
in vivo
NOS activity in pelvic ganglion nerves that is comparable to WT animals. Thus, alternatively spliced forms of nNOS are major mediators of penile erection and so may be targets for therapeutic intervention.
Overcoming photodamage in second-harmonic generation microscopy: Real-time optical recording of neuronal action potentials
Authors: Sacconi L. , Dombeck D. A. , Webb W. W.
Published: February 2006

Second-harmonic generation (SHG) has proven essential for the highest-resolution optical recording of membrane potential (Vm) in intact specimens. Here, we demonstrate single-trial SHG recordings of neuronal somatic action potentials and quantitative recordings of their decay with averaging at multiple sites during propagation along branched neurites at distances up to 350 μm from the soma. We realized these advances by quantifying, analyzing, and thereby minimizing the dynamics of photodamage (PD), a frequent limiting factor in the optical imaging of biological preparations. The optical signal and the PD during SHG imaging of stained culturedAplysianeurons were examined with intracellular electrode recordings monitoring the resting Vm variations induced by laser-scanning illumination. We found that the PD increased linearly with the dye concentration but grew with the cube of illumination intensity, leading to unanticipated optimization procedures to minimize PD. The addition of appropriate antioxidants in conjunction with an observed Vm recovery after termination of laser scanning further refined the imaging criteria for minimization and control of PD during SHG recording of action potentials. With these advances, the potential of SHG as an effective optical tool for neuroscience investigations is being realized.
Phylogenetic comparisons suggest that distance from the locus control region guides developmental expression of primate β-type globin genes
Authors: Johnson Robert M. , Prychitko Tom , Gumucio Deborah , Wildman Derek E. , Uddin Monica , Goodman Morris
Published: February 2006

Phylogenetic inferences drawn from comparative data on mammalian β-globin gene clusters indicate that the ancestral primate cluster contained a locus control region (LCR) and five paralogously related β-type globin loci (5′-LCR-ε-γ-ψη-δ-β-3′), with ε and γ expressed solely during embryonic life. A γ locus tandem duplication (5′-γ
1
-γ
2
-3′) triggered γ’s evolution toward fetal expression but by a different trajectory in platyrrhines (New World monkeys) than in catarrhines (Old World monkeys and apes, including humans). In platyrrhine (e.g.,
Cebus
) fetuses, γ
1
at the ancestral distance from ε is down-regulated, whereas γ
2
at increased distance is up-regulated. Catarrhine γ
1
and γ
2
acquired longer distances from ε (14 and 19 kb, respectively), and both are up-regulated throughout fetal life with γ
1
’s expression predominating over γ
2
’s. On enlarging the platyrrhine expression data, we find
Aotus
γ is embryonic,
Alouatta
γ is inactive at term, and in
Callithrix
, γ
1
is down-regulated fetally, whereas γ
2
is up-regulated. Of eight mammalian taxa now represented per taxon by embryonic, fetal, and postnatal β-type globin gene expression data, four taxa are primates, and data for three of these primates are from this laboratory. Our results support a model in which a short distance (<10 kb) between ε and the adjacent γ is a plesiomorphic character that allows the LCR to drive embryonic expression of both genes, whereas a longer distance (>10 kb) impedes embryonic activation of the downstream gene.
Teaching of psychology to university students in China
Authors: Zhang Houcan , Xu Yan
Published: February 2006

Psychology was first introduced into China from the Western world in the beginning of the 20th century. After the founding of the People's Republic of China in 1949, psychology was a subdiscipline under education; only after 1960 did psychology became an independent discipline. With the onset of the “Cultural Revolution” (1966–1976), when all universities were closed, psychology was severely attacked by the leftist group and was criticized as a pseudoscience. In the early 1980s, Chinese psychology was again accepted as an academic discipline. Departments of psychology were established in several universities. Since then, Chinese psychology has begun a new stage of rapid development. Although there is no uniform program in the teaching of psychology across Chinese universities, some progress in psychology education has been achieved. Along with the transition of the social‐economic system in China, the role of psychology has become more visible. It is now one of the most favoured scientific disciplines in China. In recent years many new departments of psychology have been established, and the number of students majoring in psychology has increased greatly. In order to improve the teaching of psychology, some unified textbooks have been published under the guidance of the Ministry of Education. With the help of the Chinese Psychological Society, some national conferences on the exchanging of teaching experience have been organized.
Teaching of undergraduate psychology in Russia
Authors: Karandashev Victor N.
Published: February 2006

Psychology instruction in Russia began at Moscow University in the mid‐18th century. Independent degree programs in psychology have only existed for about the last half‐century. More than 100 new psychology departments and faculties in universities that run psychology degree undergraduate programs have been established in the last decade. Many students wish to become psychologists or at least study psychology. Currently, both 4‐year and 5‐year undergraduate degree programs are offered in Russian universities. These programs are regulated by the Ministry of Education, but several local and regional differences exist among the programs. New guidelines are established every 5 years. In all institutions of higher education, two types of undergraduate programs in psychology are currently offered: Specialist degree (5 years) and Bachelor's degree (4 years). Specialist programs are designed to allow students to pursue both educational and professional goals, while Bachelor programs aim only at educational goals and do not seek to prepare professional psychologists. Psychology degree programs include many required psychology courses covering basic, applied, and methodological topics. The undergraduate programs in Russia are run according to national standards endorsed by a Ministry of Education Agency. These contain required topics for every degree. Each university then develops its curriculum, taking into account these requirements. Teaching methodology varies widely from course to course and among instructors. Small group and individual discussion and consultation, lecture, applied activities, reading, writing, and written and oral exams are utilized, as are other types of instruction. Students also complete cumulative final exams over their coursework at the end of each semester. Russian education is currently undergoing many changes, and these changes influence psychology education as well as other programs. Overall, though, programs are comparable to their European and US counterparts, with additional unique features. Psychology continues to develop as an important discipline in Russian education.
Nosocomial Transmission of Hepatitis B Virus Infection Among Residents with Diabetes in a Skilled Nursing Facility
Authors: Khan Amy J. , Cotter Suzanne M. , Schulz Beth , Hu Xiaolei , Rosenberg Jon , Robertson Betty H. , Fiore Anthony E. , Bell Beth P.
Published: February 2006

Objective:

To identify exposures associated with acute hepatitis B virus (HBV) infection among residents with diabetes in a skilled nursing facility.

Design:

Residents from Unit 3 and other skilled nursing facility residents with diabetes were tested for serologic evidence of HBV infection. Two retrospective cohort studies were conducted. Potential routes of HBV transmission were evaluated by statistical comparison of attack rates.

Setting:

A 269-bed skilled nursing facility.

Participants:

All skilled nursing facility residents with diabetes and skilled nursing facility residents who lived on the same unit as the index case (Unit 3) for some time during the case's incubation period.

Results:

All 5 residents with acute HBV infection had diabetes and resided in Unit 3. The attack rate among the 12 patients with diabetes in Unit 3 was 42%, compared with 0% among 43 patients without diabetes (relative risk, 37.2; 95% confidence interval, 4.7 to ∞). Acutely infected patients with diabetes received more morning insulin doses (P = .05), and more insulin doses (P = .03) and finger sticks (P = .02) on Wednesdays than did noninfected patients with diabetes. Two chronically infected patients with diabetes in Unit 3 were positive for hepatitis B e antigen and regularly received daily insulin and finger sticks. Of the 4 acute and 3 chronically infected residents from whom HBV DNA was amplified, all were genotype F and had an identical 678-bp S region sequence. Although no component of the lancets or injection devices was shared among residents, opportunities for HBV contamination of diabetes care supplies were identified.

Conclusions:

Contamination of diabetes care supplies resulted in resident-to-resident transmission of HBV. In any setting in which diabetes care is performed, staff need to be educated regarding appropriate infection control practices.
A Nosocomial and Occupational Cluster of Hepatitis A Virus Infection in a Pediatric Ward
Authors: Petrosillo Nicola , Raffaele Barbara , Martini Lorena , Nicastri Emanuele , Nurra Giuseppina , Anzidei Gianfranco , Ippolito Giuseppe
Published: February 2006

We describe a cluster of acute hepatitis A virus (HAV) infection that involved two patients and one physician in the pediatric unit where two children with acute HAV infection had been housed. An interview with the unit personnel revealed several breaches in infection control measures and the lack of vaccination of healthcare workers against HAV.
Incidence of Surgical-Site Infections and the Validity of the National Nosocomial Infections Surveillance System Risk Index in a General Surgical Ward in Santa Cruz, Bolivia
Authors: Soleto Lorena , Pirard Marianne , Boelaert Marleen , Peredo Remberto , Vargas Reinerio , Gianella Alberto , Stuyft Patrick Van der
Published: February 2006

Objectives:

To estimate the frequency of and risk factors for surgical-site infections (SSIs) in Bolivia, and to study the performance of the National Nosocomial Infections Surveillance (NNIS) System risk index in a developing country.

Design:

A prospective study with patient follow-up until the 30th postoperative day.

Setting:

A general surgical ward of a public hospital in Santa Cruz, Bolivia.

Patients:

Patients admitted to the ward between July 1998 and June 1999 on whom surgical procedures were performed.

Results:

Follow-up was complete for 91.5% of 376 surgical procedures. The overall SSI rate was 12%. Thirty-four (75.6%) of the 45 SSIs were culture positive. A logistic regression model retained an American Society of Anesthesiologists score of more than 1 (odds ratio [OR], 1.87), a not-clean wound class (OR, 2.28), a procedure duration of more than 1 hour (OR, 1.81), and drain (OR, 1.98) as independent risk factors for SSI. There was no significant association between the NNIS System risk index and SSI rates. However, a “local” risk index constructed with the above cut-off points showed a linear trend with SSI (P < .001) and a relative risk of 3.18 for risk class 3 versus a class of less than 3.

Conclusions:

SSIs cause considerable morbidity in Santa Cruz. Appropriate nosocomial infection surveillance and control should be introduced. The NNIS System risk index did not discriminate between patients at low and high risk for SSI in this hospital setting, but a risk score based on local cutoff points performed substantially better.
A Prospective Study of Tobacco Smoking as a Predictor of Complications in General Surgery
Authors: Delgado-Rodríguez Miguel , Medina-Cuadros Marcelino , Martínez-Gallego Gabriel , Gómez-Ortega Antonio , Mariscal-Ortiz Marcial , Palma-Pérez Silvia , Sillero-Arenas María
Published: February 2006

Objective:

To analyze whether tobacco smoking is related to nosocomial infection, admission to the intensive care unit, in-hospital death, and length of stay.

Design:

A prospective cohort study.

Setting:

The Service of General Surgery of a tertiary-care hospital.

Patients:

A consecutive series of patients admitted for more than 1 day (N = 2,989).

Results:

Sixty-two (2.1%) patients died and 503 (16.8%) acquired a nosocomial infection, of which 378 (12.6%) were surgical site and 44 (1.5%) were lower respiratory tract. Smoking (mainly past smoking) was associated with a worse health status (eg, longer preoperative stay and higher American Society of Anesthesiologists score). A long history of smoking (≥ 51 pack-years) increased post-operative admission to the intensive care unit (adjusted odds ratio [OR] = 2.86; 95% confidence interval [CI95], 1.21 to 6.77) and in-hospital mortality (adjusted OR = 2.56; CI95, 1.10 to 5.97). There was no relationship between current smoking and surgical-site infection (adjusted OR = 0.99; CI95, 0.72 to 1.35), whereas a relationship was observed between past smoking and surgical-site infection (adjusted OR = 1.46; CI95, 1.02 to 2.09). Current smoking and, to a lesser degree, past smoking augmented the risk of lower respiratory tract infection (adjusted OR = 3.21; CI95, 1.21 to 8.51). Smokers did not undergo additional surgical procedures more frequently during hospitalization. In the multivariate analysis, length of stay was similar for smokers and nonsmokers.

Conclusion:

Smoking increases in-hospital mortality, admission to the intensive care unit, and lower respiratory tract infection, but not surgical-site infection. Deleterious effects of smoking are also observed in past smokers and they cannot be counteracted by hospital cessation programs.
The Prevalence and Estimates of the Cumulative Incidence of Hospital-Acquired Infections Among Patients Admitted to Auckland District Health Board Hospitals in New Zealand
Authors: Graves Nicholas , Nicholls Tanya M. , Wong Christopher G. S. , Morris Arthur J.
Published: February 2006

Objectives:

To report the pooled results of seven prevalence surveys of hospital-acquired infections conducted between November 1996 and November 1999, and to use the data to predict the cumulative incidence of hospital-acquired infections in the same patient group.

Design:

The summary and modeling of data gathered from the routine surveillance of the point prevalence of hospital-acquired infections.

Setting:

Auckland District Health Board Hospitals (Auckland DHBH), the largest publicly funded hospital group in New Zealand supplying secondary and tertiary services.

Patients:

All inpatients.

Method:

Point-prevalence surveys were conducted including all patients in Auckland DHBH. Standard definitions of hospital-acquired infection were used. The data from the seven surveys were pooled and used in a modeling exercise to predict the cumulative incidence of hospital-acquired infection. An existing method for the conversion of prevalence to cumulative incidence was applied. Results are presented for all patients and stratified by clinical service and site of hospital-acquired infection.

Results:

The underlying patterns of hospital-acquired infection by site and service were stable during the seven time periods. The prevalence rate for all patients was 9.5%, with 553 patients identified with one or more hospital-acquired infections from a population of 5,819. The predicted cumulative incidence for all patients was 6.33% (95% confidence interval, 6.20% to 6.46%).

Conclusions:

The prevalence and the predicted cumulative incidence are similar to rates reported in the international literature. The validity of the predicted cumulative incidence derived here is not known. If it were accurate, then the application of this method would represent a cost-effective alternative to incidence studies.
Recco: recombination analysis using cost optimization
Authors: Maydt Jochen , Lengauer Thomas
Published: February 2006

Motivation: Recombination plays an important role in the evolution of many pathogens, such as HIV or malaria. Despite substantial prior work, there is still a pressing need for efficient and effective methods of detecting recombination and analyzing recombinant sequences.

Results: We introduce Recco, a novel fast method that, given a multiple sequence alignment, scores the cost of obtaining one of the sequences from the others by mutation and recombination. The algorithm comes with an illustrative visualization tool for locating recombination breakpoints. We analyze the sequence alignment with respect to all choices of the parameter α weighting recombination cost against mutation cost. The analysis of the resulting cost curve yields additional information as to which sequence might be recombinant. On random genealogies Recco is comparable in its power of detecting recombination with the algorithm Geneconv (Sawyer, 1989). For specific relevant recombination scenarios Recco significantly outperforms Geneconv.

Availability: Recco is available at

Contact:  jmaydt@mpi-inf.mpg.de
Pedigree-drawing with R and graphviz
Authors: Zhao Jing Hua
Published: February 2006

Summary: Two functions for pedigree-drawing available in R (): plot.pedigree in kinship and pedtodot in gap are described. The latter requires graphviz (). They can produce many pedigree diagrams quickly into a single file, serving as alternatives to programs that only offer interactive use.

Availability: Packages kinship and gap are available from .

Contact:  jinghua.zhao@mrc-epid.cam.ac.uk
Structural bioinformatics of DNA: a web-based tool for the analysis of molecular dynamics results and structure prediction
Authors: Dixit Surjit B. , Beveridge David L.
Published: February 2006

Summary: We report here the release of a web-based tool (MDDNA) to study and model the fine structural details of DNA on the basis of data extracted from a set of molecular dynamics (MD) trajectories of DNA sequences involving all the unique tetranucleotides. The dynamic web interface can be employed to analyze the first neighbor sequence context effects on the 10 unique dinucleotide steps of DNA. Functionality is included to build all atom models of any user-defined sequence based on the MD results. The backend of this interface is a relational database storing the conformational details of DNA obtained in 39 different MD simulation trajectories comprising all the 136 unique tetranucleotide steps. Examples of the use of this data to predict DNA structures are included.

Availability:  

Contact:  sdixit@wesleyan.edu

Supplementary information: Supplementary data including color figures are available at Bioinformatics online.
Do EPA Defendants Prefer Republicans? Evidence from the 2000 Election
Authors: Hughes Paul
Published: February 2006

The election of George W. Bush as U.S. president in 2000, as measured by the Iowa Electronic Market (IEM), was associated with an increase of 3% in the share price of firms that were being sued by the Environmental Protection Agency (EPA). This is equal to approximately $100 billion of shareholder value. This finding is robust to a number of different specifications, controlling for other litigation, case law, and industry, and is not found in an otherwise similar sample of companies without litigation outstanding. It is suggested that the enforcement of environmental law is dependent on political pressure. (JEL G18, K32, G14)
Hybridizing the Emerging European Corporation: Danone, Hachette, and the Divisionalization Process in France during the 1970s
Authors: Dessaux Pierre-Antoine , Mazaud Jean-Philippe
Published: February 2006

This article addresses the issue of the uses of the multidivisional form in the French context at the end of the 1960s and the beginning of the 1970s. Comparing two case studies, Danone and Hachette, it sheds light on specific experiences in two different industries, the food and the book industry, respectively, in order to contribute to the debate over the Chandlerian paradigm. These two cases show that the implementation of the M-form in European companies can neither be reduced to the necessary diffusion of a universal structure nor to managerial fashion. At first a matter of redistributing the power between the shareholders and the management, the M-form led to hybrid organizations with characteristics heavily dependent on intensive internal negotiations. These findings emphasize the potential diversity of the implementation of the M-form and of the relations between management and shareholders. Far from being linear, company trajectories then heavily depend on partial compromises.
Sperm design and sperm function
Authors: Malo Aurelio F , Gomendio Montserrat , Garde Julian , Lang-Lenton Barbara , Soler Ana J , Roldan Eduardo R.S
Published: February 2006

Spermatozoa vary enormously in their form and dimensions, both between and within species, yet how this variation translates into fertilizing efficiency is not known. Sperm swimming velocity is a key determinant of male fertilization success, but previous efforts to identity which sperm phenotypic traits are associated with swimming velocity have been unsuccessful. Here, we examine the relationship between the size of several sperm components and sperm swimming velocity in natural populations of red deer (
Cervus elaphus hispanicus
) where selective pressures to enhance male reproductive success are expected to be strong. Our results show that there is little within-male and considerable between-male variation in sperm dimensions. Spermatozoa with longer midpieces swim more slowly, a finding which does not support the hypothesis that the size of the midpiece determines the amount of energy which is translated into swimming speed. In contrast, spermatozoa with elongated heads, and those in which the relative length of the rest of the flagellum is longer, swim faster. Thus, the hydrodynamic shape of the head and the forces generated by the relative size of the rest of the flagellum seem to be the key determinants of sperm swimming velocity.
Modelling approaches for coastal simulation based on cellular automata: the need and potential
Authors: Dearing J.A , Richmond N , Plater A.J , Wolf J , Prandle D , Coulthard T.J
Published: February 2006

The paper summarizes the theoretical and practical needs for cellular automata (CA)-type models in coastal simulation, and describes early steps in the development of a CA-based model for estuarine sedimentation. It describes the key approaches and formulae used for tidal, wave and sediment processes in a prototype integrated cellular model for coastal simulation designed to simulate estuary sedimentary responses during the tidal cycle in the short-term and climate driven changes in sea-level in the long-term. Results of simple model testing for both one-dimensional and two-dimensional models, and a preliminary parameterization for the Blackwater Estuary, UK, are shown. These reveal a good degree of success in using a CA-type model for water and sediment transport as a function of water level and wave height, but tidal current vectors are not effectively simulated in the approach used. The research confirms that a CA-type model for the estuarine sediment system is feasible, with a real prospect for coupling to existing catchment and nearshore beach/cliff models to produce integrated coastal simulators of sediment response to climate, sea-level change and human actions.
Chemical Imaging of Poplar Wood Cell Walls by Confocal Raman Microscopy
Authors: Gierlinger Notburga , Schwanninger Manfred
Published: February 2006

Confocal Raman microscopy was used to illustrate changes of molecular composition in secondary plant cell wall tissues of poplar (Populus nigra × Populus deltoids) wood. Two-dimensional spectral maps were acquired and chemical images calculated by integrating the intensity of characteristic spectral bands. This enabled direct visualization of the spatial variation of the lignin content without any chemical treatment or staining of the cell wall. A small (0.5 μm) lignified border toward the lumen was observed in the gelatinous layer of poplar tension wood. The variable orientation of the cellulose was also characterized, leading to visualization of the S1 layer with dimensions smaller than 0.5 μm. Scanning Raman microscopy was thus shown to be a powerful, nondestructive tool for imaging changes in molecular cell wall organization with high spatial resolution.