bluuebunny/crossref_metadata_2025 huggingface dataset:
SIGNIFICANT VARIABLE SELECTION AND AUTOREGRESSIVE ORDER DETERMINATION FOR TIME‐SERIES PARTIALLY LINEAR MODELS
Authors: Li Degao , Li Guodong , You Jinhong
Published: July 2014

This paper is concerned with the regression coefficient and autoregressive order shrinkage and selection via the smoothly clipped absolute deviation (SCAD) penalty for a partially linear model with time‐series errors. By combining the profile semi‐parametric least squares method and SCAD penalty technique, a new penalized estimation for the regression and autoregressive parameters in the model is proposed. We show that the asymptotic property of the resultant estimator is the same as if the order of autoregressive error structure and non‐zero regression coefficients are known in advance, thus achieving the oracle property in the sense of Fan and Li (2001). In addition, based on a prewhitening technique, we construct a two‐stage local linear estimator (TSLLE) for the non‐parametric component. It is shown that the TSLLE is more asymtotically efficient than the one that ignores the autoregressive time‐series error structure. Some simulation studies are conducted to illustrate the finite sample performance of the proposed procedure. An example of application on electricity usage data is also illustrated. Copyright © 2014 Wiley Publishing Ltd
Toxicokinetics of T‐2 toxin and its major metabolites in broiler chickens after intravenous and oral administration
Authors: Sun Y. X. , Yao X. , Shi S. N. , Zhang G. J. , Xu L. X. , Liu Y. J. , Fang B. H.
Published: July 2014

T‐2 toxin, one of the most toxic trichothecene mycotoxins, causes economic losses in animal production. Little information is available on the toxicokinetic parameters of T‐2 toxin and its major metabolites (i.e., HT‐2 toxin and T‐2 triol) in broiler chickens. In this study, toxicokinetics of T‐2 toxin and its major metabolites were evaluated in broiler chickens after a single intravenous (0.5 mg/kg b.w.) and multiple oral administrations (2.0 mg/kg b.w., every 12 h for 2 days). Plasma concentration profiles of T‐2 toxin and its metabolites were analyzed by a noncompartmental model method. Following intravenous administration, the terminal elimination half‐lives (t1/2λz) of T‐2 toxin, HT‐2 toxin, and T‐2 triol were 17.33 ± 1.07 min, 33.62 ± 3.08 min, and 9.60 ± 0.50 min, respectively. Following multiple oral administrations, no plasma levels above the limit of quantification were observed for HT‐2 toxin. The t1/2λz of T‐2 toxin and T‐2 triol was 23.40 ± 2.94 min and 87.60 ± 29.40 min, respectively. Peak plasma concentrations (Cmax) of 53.10 ± 10.42 ng/mL (T‐2 toxin) and 47.64 ± 9.19 ng/mL (T‐2 triol) were observed at Tmax of 13.20 ± 4.80 min and 38.40 ± 15.00 min, respectively. T‐2 toxin had a low absolute oral bioavailability (17.07%). Results showed that the T‐2 toxin was rapidly absorbed and most of the T‐2 toxin was extensively transformed to metabolites in broiler chickens.
Angiotensin‐(1‐7) Prevents Angiotensin II‐induced Fibrosis in Cremaster Microvessels
Authors: Carver Kyle A. , Smith Thomas L. , Gallagher Patricia E. , Tallant E. Ann
Published: July 2014

Objective

The effect of the heptapeptide hormone Ang‐(1‐7) on microvascular fibrosis in rats with Ang II‐induced hypertension was investigated, since vascular fibrosis/remodeling plays a prominent role in hypertension‐induced end‐organ damage and Ang‐(1‐7) inhibits vascular growth and fibrosis.

Methods

Fibrosis of cremaster microvessels was studied in male Lewis rats infused with Ang II and/or Ang‐(1‐7).

Results

Ang II elevated systolic blood pressure by approximately 40 mmHg, while blood pressure was not changed by Ang‐(1‐7). Ang II increased perivascular fibrosis surrounding 20–50 μm arterioles as well as interstitial fibrosis; coadministration of Ang‐(1‐7) prevented the increases in fibrosis. The fibrotic factor CTGF and phospho‐Smad 2/3, which upregulates CTGF, were increased by Ang II; this effect was prevented by coadministration of Ang‐(1‐7). Although TGF‐β phosphorylates Smad 2/3, TGF‐β was no different among treatment groups. In contrast, Ang II increased the MAP kinase phospho‐ERK1/2, which also phosphorylates Smad; p‐ERK was reduced by Ang‐(1‐7). Ang‐(1‐7), in the presence or absence of Ang II, upregulated the MAP kinase phosphatase DUSP1.

Conclusions

These results suggest that Ang‐(1‐7) increases DUSP1 to reduce MAP kinase/Smad/CTGF signaling and decrease fibrosis in resistance arterioles, to attenuate end‐organ damage associated with chronic hypertension.
Laboratory and field evaluations of chemical and plant‐derived potential repellents against Culicoides biting midges in northern Spain
Authors: GONZÁLEZ M. , VENTER G. J. , LÓPEZ S. , ITURRONDOBEITIA J. C. , GOLDARAZENA A.
Published: July 2014

The efficacy of 23 compounds in repelling Culicoides biting midges (Diptera: Ceratopogonidae), particularly Culicoides obsoletus (Meigen) females, was determined by means of a Y‐tube olfactometer. The 10 most effective compounds were further evaluated in landing bioassays. The six most promising compounds (including chemical and plant‐derived repellents) were evaluated at 10% and 25% concentrations in field assays using Centers for Disease Control (CDC) light traps. At least three compounds showed promising results against Culicoides biting midges with the methodologies used. Whereas olfactometer assays indicated DEET at 1 µg/µL to be the most effective repellent, filter paper landing bioassays showed plant‐derived oils to be better. Light traps fitted with polyester mesh impregnated with a mixture of octanoic, decanoic and nonanoic fatty acids at 10% and 25% concentrations collected 2.2 and 3.6 times fewer midges than control traps and were as effective as DEET, which is presently considered the reference standard insect repellent. The best plant‐derived product was lemon eucalyptus oil. Although these have been reported as safe potential repellents, the present results indicate DEET and the mixture of organic fatty acids to be superior and longer lasting.
Whole plastome sequencing reveals deep plastid divergence and cytonuclear discordance between closely related balsam poplars, Populus balsamifera and P. trichocarpa (Salicaceae)
Authors: Huang Daisie I. , Hefer Charles A. , Kolosova Natalia , Douglas Carl J. , Cronk Quentin C. B.
Published: July 2014

As molecular phylogenetic analyses incorporate ever‐greater numbers of loci, cases of cytonuclear discordance – the phenomenon in which nuclear gene trees deviate significantly from organellar gene trees – are being reported more frequently. Plant examples of topological discordance, caused by recent hybridization between extant species, are well known. However, examples of branch‐length discordance are less reported in plants relative to animals.

We use a combination of de novo assembly and reference‐based mapping using short‐read shotgun sequences to construct a robust phylogeny of the plastome for multiple individuals of all the common Populus species in North America.

We demonstrate a case of strikingly high plastome divergence, in contrast to little nuclear genome divergence, in two closely related balsam poplars, Populus balsamifera and Populus trichocarpa (Populus balsamifera ssp. trichocarpa). Previous studies with nuclear loci indicate that the two species (or subspecies) diverged since the late Pleistocene, whereas their plastomes indicate deep divergence, dating to at least the Pliocene (6–7 Myr ago).

Our finding is in marked contrast to the estimated Pleistocene divergence of the nuclear genomes, previously calculated at 75 000 yr ago, suggesting plastid capture from a ‘ghost lineage’ of a now‐extinct North American poplar.
The Oaxaca–Blinder Unexplained Component as a Treatment Effects Estimator
Authors: Słoczyński Tymon
Published: July 2014

In this paper I use the National Supported Work (NSW) data to examine the finite‐sample performance of the Oaxaca–Blinder unexplained component as an estimator of the population average treatment effect on the treated (PATT). Precisely, I follow sample and variable selections from Dehejia and Wahba (1999), and conclude that Oaxaca–Blinder performs better than any of the estimators in this influential paper, provided that overlap is imposed. As a robustness check, I consider alternative sample (Smith and Todd, 2005) and variable (Abadie and Imbens, 2011) selections, and present a simulation study which is also based on the NSW data.
Inflation perceptions and expectations in Sweden – Are media reports the missing link?
Authors: Dräger Lena
Published: July 2014

We analyze the interrelation between consumers' quantitative inflation perceptions and expectations as well as actual inflation rates in Sweden. The role of media reports about inflation is emphasized. Structural vector error correction models show stable cointegration between actual, perceived and expected inflation. Impulse responses and forecast error variance decompositions suggest strong interaction between perceived and expected inflation, with a lesser role for actual inflation. Media effects are generally small, but imply an asymmetric reaction of inflation expectations and perceptions to news on increasing vs. decreasing inflation. Thus, to anchor inflation expectations, central banks should explore better communication channels to inform consumers about actual inflation.
Response of the European grapevine moth Lobesia botrana to somatosensory‐active volatiles emitted by the non‐host plant Perilla frutescens
Authors: Cattaneo Alberto M. , Bengtsson Jonas M. , Borgonovo Gigliola , Bassoli Angela , Anfora Gianfranco
Published: July 2014

The European grapevine moth Lobesia botrana Denis & Schiffermüller (Lepidoptera: Tortricidae) is a major pest on grapes worldwide. Attempts to develop control methods for this pest based on grape kairomones demonstrate limited success and studies indicate that a major limiting factor is overlap between synthetic kairomones and background odours in the vineyard. Behaviourally active compounds from non‐host plants may thus represent an effective alternative for monitoring and control methods. Extracts from food plants (i.e. from capsicum, garlic and peppermint, which elicit the so‐called somatosensory sensation) are traditionally used in agriculture for the control of pest insects. Among those plants, Perilla frutescens L. (Lamiales: Lamiaceae), native of Asia, contains compounds activating sensory ion channels in mammals, which are known to be involved in the perception of somatosensory compounds and are expressed in tortricid moth antennae. In the present study, in search of non‐host volatiles with potential application in pest control, essential oil metabolites isolated from P. frutescens are screened for biological activity on the olfactory system of L. botrana. The compounds (S)‐(−)‐perillaldehyde and isoegomaketone, which are released from different P. frutescens varieties, are identified by gas chromatography‐coupled electroantennographic detection. In a dual‐choice oviposition test, females show a preference for a combination of host odours and perillaldehyde, preferring this over a host‐plant odour bouquet alone. In Y‐tube olfactometer assays, virgin males show a higher level of activity in the presence of isoegomaketone, even if not significantly responsive to the compound.
Is Mining Fuelling Long‐Run Growth in Russia? Industry Productivity Growth Trends Since 1995
Authors: Timmer Marcel P. , Voskoboynikov Ilya B.
Published: July 2014

GDP per capita growth rates in Russia have been amongst the highest in the world since the mid‐1990s. Previous growth accounting research at the macro‐level suggests that this was mainly driven by multi‐factor productivity (MFP) growth. In this paper we analyze for the first time the drivers of Russian growth at the level of industries. We derive a proper measure of capital services, instead of using stock measures as in previous research. Using this, we find that aggregate GDP growth is driven as much by capital input as MFP growth. Mining and Retailing industries are growing fast, but have poor MFP performance. In contrast, MFP growth was high in goods‐producing industries but their share in GDP declined. MFP growth was highest in those industries that were particularly underdeveloped in the Russian economy in the 1990s.
On Bi‐Polarization and The Middle Class in Latin America: A Look At the First Decade of the Twenty‐First Century
Authors: Deutsch Joseph , Silber Jacques , Yalonetzky Gaston
Published: July 2014

This paper proposes new measures and graphical representations of the change in bi‐polarization and in the relative importance of the middle class that took place in a given country during a given period. These tools extend, in fact, the concepts of inter‐distribution income inequality and Lorenz curves by making, first, a distinction between overall, “pure growth based” and “shape related” distributional changes; and then between a “first‐order” and a “second‐order” change in “shape related” distributional change. The empirical illustration is based on data covering 17 Latin American countries in 2000 and 2009, obtained from the Latinobarómetro surveys for these years. The standard of living of individuals was derived on the basis of correspondence analysis. These new tools help us to understand the changes that took place in the distribution of standards of living during the period analyzed.
Year in School and Physical Activity Stage of Change as Discriminators of Variation in the Physical Activity Correlate Profile of Adolescent Females
Authors: Burns Con , Murphy John J. , MacDonncha Ciaran
Published: July 2014

Background:

Knowledge of the physical activity correlate profile of adolescent females will provide insight into decreasing physical activity patterns among adolescent females.

Methods:

Correlates of physical activity and physical activity stage of change were assessed during 2007–2008 among 871 Irish adolescent females in years 1–6 in secondary schools (15.28 ± 1.8 years). Multivariate Analysis of Variance was used to identify whether differences in correlates of physical activity could be detected across year in school and physical activity stages of change.

Results:

Significant differences (P < .01) were found in 11 of the 16 measured correlates across year in school and in 14 of the 16 correlates across stage of change. Effect size estimates and regression analysis revealed perceived competence, peer social support and intention to be physically active (partial eta range (ηp2) .21–.25) to be the most important predictors of physical activity stage of change.

Conclusions:

Females in more senior years in school and in earlier physical activity stages of change reported a significantly less positive physical activity correlate profile than females in junior years and in later physical activity stages of change. This finding supports the construct validity of the physical activity stages of change.
Socioeconomic Status and Objectively Measured Physical Activity in Thai Adolescents
Authors: Konharn Kurusart , Santos Maria Paula , Ribeiro José Carlos
Published: July 2014

Background:

The impact of socioeconomic status (SES) on objective measures of physical activity (PA) in adolescence is poorly understood. The purpose of this cross-sectional study was to evaluate the association between SES and objectively measured PA in Thai adolescents.

Methods:

PA was objectively measured every 30 seconds for 7 consecutive days using ActiGraph GT1M uniaxial accelerometers in 177 secondary-school adolescents aged 13 to 18 years that were classified into 3 SES groups (low, middle, and high). The associations between SES and adolescents’ PA were examined using 1-way ANOVA with multiple comparisons and Chi-square test.

Results:

Adolescents of low-SES accumulated more minutes of PA and less of sedentary behavior than those of high-SES, Additionally, low-SES adolescents tended to meet the daily PA guidelines more than other groups, particularly in girls (P < .01).

Conclusions:

This study evidences an inverse relationship between SES and PA levels, and shows the importance of targeting high SES adolescents in intervention programs to enhance health behaviors. Based on these findings, we also suggest that SES must be considered as an important determinant in promoting regular PA and in increasing proportions of adolescents meeting current health-related PA guidelines.
The Role of Exergaming in Improving Physical Activity: A Review
Authors: Sween Jennifer , Wallington Sherrie Flynt , Sheppard Vanessa , Taylor Teletia , Llanos Adana A. , Adams-Campbell Lucile Lauren
Published: July 2014

Background:

The high prevalence of obesity in America can be attributed to inadequate energy expenditure as a result of high levels of physical inactivity. This review presents an overview of the current literature on physical activity, specifically through active videogame systems (exergaming) and how these systems can help to increase physical activity levels.

Methods:

The search strategy for this review was to identify previous studies that investigated energy expenditure levels using a single active video game or a combination of active videogames.

Results:

Based on data from 27 studies, a strong correlation exists between exergaming and increased energy expenditure (up to 300% above resting levels). The majority of active videogames tested were found to achieve physical activity levels of moderate intensity, which meet American College of Sports Medicine guidelines for health and fitness.

Conclusions:

Exergaming is a new and exciting strategy to potentially improve physical activity levels and reduce obesity among Americans.
Cognitive Function During Low-Intensity Walking: A Test of the Treadmill Workstation
Authors: Alderman Brandon L. , Olson Ryan L. , Mattina Diana M.
Published: July 2014

Background:

The purpose of this study was to examine the effects of walking at self-selected speed on an active workstation on cognitive performance.

Methods:

Sixty-six participants (n = 27 males, 39 females; mean age = 21.06 ± 1.6 years) completed a treadmill-desk walking and a seated control condition, separated by 48 hours. During each condition, participants completed computerized versions of the Stroop test, a modified flanker task, and a test of reading comprehension.

Results:

No significant differences in response speed or accuracy were found between walking and sitting conditions for any the cognitive tests.

Conclusions:

These findings reveal that performance on cognitive tasks, including executive control processes, are not impaired by walking on an active workstation. Implementing active workstations into offices and classrooms may help to decrease sedentariness without impairing task performance.
Evidence for Adapted Physical Activity as an Effective Intervention for Upper Limb Mobility and Quality of Life in Breast Cancer Survivors
Authors: Mirandola Daniela , Miccinesi Guido , Muraca Maria Grazia , Sgambati Eleonora , Monaci Marco , Marini Mirca
Published: July 2014

Background:

Physical activity interventions are known to be effective in improving the physical and psychological complaints of breast cancer survivors.

Purpose:

To investigate the impact of a specific exercise training program on upper limb mobility and quality of life in breast cancer survivors.

Methods:

The study included 55 women recruited at the Cancer Rehabilitation Centre in Florence after the completion of breast cancer treatment and rehabilitative physiotherapy. All participants underwent an 8-week specific exercise training to improve upper limb mobility function and quality of life. Anthropometric parameters were measured, and each subject underwent a battery of fitness tests to assess shoulder-arm mobility, range of motion, and back flexibility before and after specific exercise program. All participants filled out the Short Form-12 and numerical rating scale questionnaires to assess the quality of life and to quantify back and shoulder pain intensity.

Results:

The evaluation of shoulder-arm mobility and self-reported questionnaire data revealed a statistically significant improvement after completion of our specific exercise program.

Conclusion:

An organized specific program of adapted physical activity can be effective in reducing the main adverse effects of surgery and oncological therapy, and may significantly improve shoulder-arm mobility and quality of life in breast cancer survivors.
Longitudinal and Cross-Sectional Associations of Physical Activity With Triglyceride and HDLc Levels in Young Male Adults
Authors: Bielemann Renata Moraes , Ramires Virgílio Viana , Gigante Denise Petrucci , Hallal Pedro Curi , Horta Bernardo Lessa
Published: July 2014

Background:

The purpose of this study was to evaluate cross-sectional and longitudinal associations between physical activity and triglyceride and HDLc levels in young male adults.

Methods:

We used information about males belonging 1982 Pelotas Birth Cohort. Physical activity in 4 domains (leisure time, transportation, household, and occupation) was assessed by self-report in participants of the cohort at ages of 18 and 23 years. Subjects were active if reached the recommendation of 150 min/week of moderate to vigorous physical activity. At 23 years of age, blood sample was collected, and triglycerides and HDLc levels estimated. Multivariate linear and Poisson regression were used to adjust the estimates for confounders.

Results:

Males who were inactive at 18 and active at 23 years had 41% lower risk (β = 0.59; 95% confidence interval: 0.40; 0.89) for borderline-high triglycerides (≥ 150 mg/dL) as compared with those who were inactive at both follow-ups. No association was found between changes of physical activity and HDLc level. In cross-sectional analyses, greater HDLc levels were found in active subjects in 4 domains, whereas there was no difference in HDL levels according physical activity during leisure time.

Conclusion:

Becoming active from adolescence to early adulthood reduced the risk for high triglycerides. Current physical activity was associated with greater HDLc levels.
Associations of School Violence With Physical Activity Among U.S. High School Students
Authors: Demissie Zewditu , Lowry Richard , Eaton Danice K. , Hertz Marci F. , Lee Sarah M.
Published: July 2014

Background:

This study investigated associations of violence-related behaviors with physical activity (PA)-related behaviors among U.S. high school students.

Methods:

Data from the 2009 national Youth Risk Behavior Survey, a cross-sectional survey of a nationally representative sample of 9th–12th grade students, were analyzed. Sex-stratified, adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated for associations between violence-related behaviors and being physically active for ≥ 60 minutes daily, sports participation, TV watching for ≥ 3 hours/day, and video game/computer use for ≥ 3 hours/day.

Results:

Among male students, at-school bullying victimization was negatively associated with daily PA (aOR: 0.72; 95% CI: 0.58–0.87) and sports participation; skipping school because of safety concerns was positively associated with video game/computer use (1.42; 1.01–2.00); and physical fighting was positively associated with daily PA. Among female students, atschool bullying victimization and skipping school because of safety concerns were both positively associated with video game/computer use (1.46; 1.19–1.79 and 1.60; 1.09–2.34, respectively), and physical fighting at school was negatively associated with sports participation and positively associated with TV watching.

Conclusions:

Bullying victimization emerged as a potentially important risk factor for insufficient PA. Schools should consider the role of violence in initiatives designed to promote PA.
Direct Observation is a Valid Criterion for Estimating Physical Activity and Sedentary Behavior
Authors: Lyden Kate , Petruski Natalia , Mix Stephanie , Staudenmayer John , Freedson Patty
Published: July 2014

Background:

Physical activity and sedentary behavior measurement tools need to be validated in free-living settings. Direct observation (DO) may be an appropriate criterion for these studies. However, it is not known if trained observers can correctly judge the absolute intensity of free-living activities.

Purpose:

To compare DO estimates of total MET-hours and time in activity intensity categories to a criterion measure from indirect calorimetry (IC).

Methods:

Fifteen participants were directly observed on three separate days for two hours each day. During this time participants wore an Oxycon Mobile indirect calorimeter and performed any activity of their choice within the reception area of the wireless metabolic equipment. Participants were provided with a desk for sedentary activities (writing, reading, computer use) and had access to exercise equipment (treadmill, bike).

Results:

DO accurately and precisely estimated MET-hours [% bias (95% CI) = –12.7% (–16.4, –7.3), ICC = 0.98], time in low intensity activity [% bias (95% CI) = 2.1% (1.1, 3.2), ICC = 1.00] and time in moderate to vigorous intensity activity [% bias (95% CI) –4.9% (–7.4, –2.5), ICC = 1.00].

Conclusion:

This study provides evidence that DO can be used as a criterion measure of absolute intensity in free-living validation studies.
Fidelity in Models-Based Practice Research in Sport Pedagogy: A Guide for Future Investigations
Authors: Hastie Peter A. , Casey Ashley
Published: July 2014

This paper provides a commentary on research on models-based practice within physical education and presents a tutorial that aims to guide the reporting of future research using pedagogical models. Three key elements are presented that could be considered as essential for inclusion in any methods section in order for readers to gain an accurate and complete understanding of the results of studies. These are (a) rich description of the curricular elements of the unit, (b) a detailed validation of model implementation, and (c) a detailed description of the program context that includes the previous experiences of the teacher and students with the model or with models-based practice. Examples of why these are particularly prudent are provided by reference to papers reporting the outcomes of several currently used models (e.g., Sport Education, Teaching Games for Understanding, and Cooperative Learning).
Highly active copper-ceria and copper-ceria-titania catalysts for methanol synthesis from CO
2
Authors: Graciani Jesús , Mudiyanselage Kumudu , Xu Fang , Baber Ashleigh E. , Evans Jaime , Senanayake Sanjaya D. , Stacchiola Darío J. , Liu Ping , Hrbek Jan , Sanz Javier Fernández , Rodriguez José A.
Published: July 2014

Converting CO
2
into methanol by catalysis

By hydrogenating CO
2
, scientists can transform a greenhouse gas into methanol, a desirable fuel. Graciani
et al.
cast copper in the role of the highly active catalyst for this reaction by putting copper particles on cerium oxide. The interface between the cerium oxide and the copper enables the reverse water-gas shift reaction that converts CO
2
into CO, which reacts more readily with hydrogen to make methanol. This result takes a step forward in innovating catalysts for this environmentally friendly process.

Science
, this issue p.
546
Decreased motivation during chronic pain requires long-term depression in the nucleus accumbens
Authors: Schwartz Neil , Temkin Paul , Jurado Sandra , Lim Byung Kook , Heifets Boris D. , Polepalli Jai S. , Malenka Robert C.
Published: July 2014

A neuropeptide kills patient's motivation

Chronic pain is not only extremely disturbing and unpleasant; it can also make people depressed and demotivated. What causes these effects? Schwartz
et al.
discovered that chronic pain causes changes in the way a neuropeptide called galanin affects certain neurons in a brain region called the nucleus accumbens (see the Perspective by Fields). Galanin influences a variety of behaviors, including feeding and certain aspects of pain. In this case, it depresses synaptic transmission at specific excitatory synapses. It does so, in part, by changing the ratio of subunits of an important receptor protein.

Science
, this issue p.
535
; see also p.
513
Fast-spiking, parvalbumin
+
GABAergic interneurons: From cellular design to microcircuit function
Authors: Hu Hua , Gan Jian , Jonas Peter
Published: July 2014

Background

Neuronal networks in the brain include glutamatergic principal neurons and GABAergic interneurons (GABA, γ-aminobutyric acid). The latter may be a minority cell type, but they are vital for normal brain function because they regulate the activity of principal neurons. If interneuron function is impaired, higher brain function can be damaged and seizures may result. The fast-spiking, parvalbumin-positive interneurons (PV
+
interneurons) are readily characterized and, consequently, have been adopted as a research model for systematic and quantitative investigations. These cells contribute to feedback and feedforward inhibition and are critically involved in the generation of network oscillations. They can convert an excitatory input signal into an inhibitory output signal within a millisecond, but it is unclear how these signaling properties are implemented at the molecular and cellular levels, nor how PV
+
interneurons shape complex network functions.

Advances

Recent work sheds light on the subcellular signaling properties of PV
+
interneurons. PV
+
cells show a high degree of polarity. The weakly excitable dendrites allow PV
+
interneurons to sample activity in the surrounding network, whereas the highly excitable axons enable analog-to-digital conversion and fast propagation of the digital signal to a large number of target cells. Additionally, tight coupling of Ca
2+
channels and release sensors at GABAergic output synapses increases the efficacy and speed of the inhibitory output.

Recent results also provide a better understanding of how PV
+
interneurons operate in neuronal networks. Not only are PV
+
interneurons involved in basic microcircuit functions, such as feedforward and feedback inhibition or gamma-frequency oscillations, but they also play a role in complex network operations, including expansion of dynamic activity range, pattern separation, modulation of place and grid field shapes, phase precession, and gain modulation of sensory responses. Thus, PV
+
interneurons are critically involved in advanced computations in microcircuits and neuronal networks.

Outlook

Parvalbumin-expressing interneurons may also play a key role in numerous brain diseases. These include epilepsy, but also complex psychiatric diseases such as schizophrenia. Thus, PV
+
interneurons may become important therapeutic targets in the future. However, much needs to be learned about the basic function of these interneurons before clinical neuroscientists will have a chance to successfully use PV
+
interneurons for therapeutic purposes.
In Turing's hands—the making of digits
Authors: Zuniga Aimée , Zeller Rolf
Published: July 2014

A Turing network controls the periodic pattern of fingers and toes during development

[Also see Report by

Raspopovic
et al.

]
How birds became birds
Authors: Benton Michael J.
Published: July 2014

Sustained size reduction was essential for the origin of birds and avian flight

[Also see Report by

Lee
et al.

]
How helminths go viral
Authors: Maizels Rick M , Gause William C
Published: July 2014

Cellular signals during helminth infections can skew the immune response to favor viral spreading

[Also see Reports by

Reese
et al.

and

Osborne
et al.

]
Zero hunger
Authors: Swaminathan M. S.
Published: July 2014

The United Nations (UN) designated 2014 as the International Year of Family Farming, recognizing that an estimated 500 million family farms, involving over 2 billion people, play a key role in food production and consumption worldwide. It is thus an opportune time to encourage a shift in tackling global hunger—from a “food security” focus to an agenda that promotes “nutrition security” instead. The drive to reduce hunger in the world has largely relied on crops such as wheat and rice that provide calories. But an increase in calories alone is not good enough. Improved diets and good health require bolstering nutrition.
Money woes cripple Venezuela's health system
Authors: Wade Lizzie
Published: July 2014

Lacking vital medical supplies, doctors struggle to treat resurgent diseases.
Decision looms on future of E.U. science advice
Authors: Kupferschmidt Kai
Published: July 2014

Green groups criticize current adviser—and her office.
Deadly quakes divide experts
Authors: Cartlidge Edwin
Published: July 2014

New industry-sponsored study rules out any link between Italian earthquakes and oil production.
Comet catcher
Authors: Hand Eric
Published: July 2014

Europe's Rosetta spacecraft is about to orbit and then land on one of the solar system's most mysterious objects.
Touch and go
Authors: Hand Eric
Published: July 2014

The most daring moment of the Rosetta mission will come when mission leaders plan to drop the Philae lander to the surface of comet 67P/Churyumov-Gerasimenko.
Central command
Authors: Leslie Mitch
Published: July 2014

More capable than once thought, the cellular structure known as the nucleolus may be a target for treating diseases.
Dietary Rice Bran Protects against Rotavirus Diarrhea and Promotes Th1-Type Immune Responses to Human Rotavirus Vaccine in Gnotobiotic Pigs
Authors: Yang Xingdong , Wen Ke , Tin Christine , Li Guohua , Wang Haifeng , Kocher Jacob , Pelzer Kevin , Ryan Elizabeth , Yuan Lijuan
Published: July 2014

Rice bran (RB) contains a distinct stoichiometry of phytochemicals that can promote gut mucosal immune responses against enteric pathogens. The effects of RB on rotavirus diarrhea and immunogenicity of an attenuated human rotavirus (HRV) vaccine were evaluated in gnotobiotic pigs. The four treatment groups studied were RB plus vaccine, vaccine only, RB only, and mock control. Pigs in the RB groups were fed the amount of RB that replaced 10% of the pigs' total daily calorie intake from milk starting from 5 days of age until they were euthanized. Pigs in the vaccine groups were orally inoculated with two doses of the attenuated HRV vaccine. A subset of pigs from each group was orally challenged with the homologous virulent HRV on postinoculation day 28. Diarrhea and virus shedding were monitored daily from postchallenge day 0 to day 7. RB feeding significantly protected against diarrhea upon virulent HRV challenge and enhanced the protective rate of the vaccine against rotavirus diarrhea. Consistent with protection, RB significantly increased gamma interferon (IFN-γ)-producing CD4
+
and CD8
+
T cell responses in intestinal and systemic lymphoid tissues. Furthermore, RB also increased the number of total IgM- and IgA-secreting cells, total serum IgM, IgG, and IgA titers, and HRV-specific IgA titers in intestinal contents. RB reduced the numbers of intestinal and systemic HRV-specific IgA and IgG antibody-secreting cells and reduced serum HRV-specific IgA and IgG antibody titers before the challenge. These results demonstrate clear beneficial effects of RB in protection against rotavirus diarrhea and stimulation of nonspecific and HRV-specific immune responses, as well as its biased Th1-type adjuvant effect for the vaccine.
Recombinant Mycobacterium bovis Bacillus Calmette-Guérin Vectors Prime for Strong Cellular Responses to Simian Immunodeficiency Virus Gag in Rhesus Macaques
Authors: Sixsmith Jaimie D. , Panas Michael W. , Lee Sunhee , Gillard Geoffrey O. , White KeriAnn , Lifton Michelle A. , Balachandran Harikrishnan , Mach Linh , Miller John P. , Lavine Christy , DeMarco C. Todd , Tomaras Georgia D. , Gee Connie , Porcelli Steven A. , Larsen Michelle H. , Frothingham Richard , Schmitz Joern E. , Jacobs William R. , Haynes Barton F. , Letvin Norman L. , Korioth-Schmitz Birgit
Published: July 2014

Live attenuated nonpathogenicMycobacterium bovisbacillus Calmette-Guérin (BCG) mediates long-lasting immune responses, has been safely administered as a tuberculosis vaccine to billions of humans, and is affordable to produce as a vaccine vector. These characteristics make it very attractive as a human immunodeficiency virus (HIV) vaccine vector candidate. Here, we assessed the immunogenicity of recombinant BCG (rBCG) constructs with different simian immunodeficiency virus (SIV)gagexpression cassettes as priming agents followed by a recombinant replication-incompetent New York vaccinia virus (NYVAC) boost in rhesus macaques. Unmutated rBCG constructs were used in comparison to mutants with gene deletions identified in anin vitroscreen for augmented immunogenicity. We demonstrated that BCG-SIVgagis able to elicit robust transgene-specific priming responses, resulting in strong SIV epitope-specific cellular immune responses. While enhanced immunogenicity was sustained at moderate levels for >1 year following the heterologous boost vaccination, we were unable to demonstrate a protective effect after repeated rectal mucosal challenges with pathogenic SIVmac251. Our findings highlight the potential for rBCG vaccines to stimulate effective cross-priming and enhanced major histocompatibility complex class I presentation, suggesting that combining this approach with other immunogens may contribute to the development of effective vaccine regimens against HIV.
Group A Streptococcus Expresses a Trio of Surface Proteins Containing Protective Epitopes
Authors: Niedermeyer Shannon E. , Penfound Thomas A. , Hohn Claudia , Li Yi , Homayouni Ramin , Zhao Jingnan , Dale James B.
Published: July 2014

Group A streptococci (GAS) (Streptococcus pyogenes) are common causes of infections in humans for which there is no licensed vaccine. Decades of work has focused on the role of the surface M protein in eliciting type-specific protective immunity. Recent studies have identified additional surface proteins of GAS that contain opsonic epitopes. In the present study, we describe a serotype M65 GAS originally isolated during an epidemiologic study in Bamako, Mali, which simultaneously expressed M, M-related protein (Mrp), and streptococcal protective antigen (Spa) on the bacterial surface. Theemm,mrp, andspagenes were sequenced from PCR amplicons derived from the M65 chromosome. Rabbit antisera raised against synthetic peptides copying the N-terminal regions of M, Mrp, and Spa were highly specific for each peptide, reacted with the surface of M65 GAS, and promoted bactericidal activity against the organism. A mixture of antisera against all three peptides was most effective in the bactericidal assays. Immunofluorescence microscopy revealed that the M, Mrp, and Spa antisera bound to the bacterial surface in the presence of human plasma proteins and resulted in the deposition of complement. Five additionalspagenes were identified in the Mrp-positive GAS serotypes, and their sequences were determined. Our results indicate that there are multiple antigens on the surface of GAS that evoke antibodies that promote bacterial killing. A more complete understanding of the relative contributions of M, Mrp, and Spa in eliciting protective immunity may aid in the development of GAS vaccines with enhanced coverage and efficacy.
Analysis of Culture-Dependent versus Culture-Independent Techniques for Identification of Bacteria in Clinically Obtained Bronchoalveolar Lavage Fluid
Authors: Dickson Robert P. , Erb-Downward John R. , Prescott Hallie C. , Martinez Fernando J. , Curtis Jeffrey L. , Lama Vibha N. , Huffnagle Gary B.
Published: July 2014

The diagnosis and management of pneumonia are limited by the use of culture-based techniques of microbial identification, which may fail to identify unculturable, fastidious, and metabolically active viable but unculturable bacteria. Novel high-throughput culture-independent techniques hold promise but have not been systematically compared to conventional culture. We analyzed 46 clinically obtained bronchoalveolar lavage (BAL) fluid specimens from symptomatic and asymptomatic lung transplant recipients both by culture (using a clinical microbiology laboratory protocol) and by bacterial 16S rRNA gene pyrosequencing. Bacteria were identified in 44 of 46 (95.7%) BAL fluid specimens by culture-independent sequencing, significantly more than the number of specimens in which bacteria were detected (37 of 46, 80.4%,
P
≤ 0.05) or “pathogen” species reported (18 of 46, 39.1%,
P
≤ 0.0001) via culture. Identification of bacteria by culture was positively associated with culture-independent indices of infection (total bacterial DNA burden and low bacterial community diversity) (
P
≤ 0.01). In BAL fluid specimens with no culture growth, the amount of bacterial DNA was greater than that in reagent and rinse controls, and communities were markedly dominated by select
Gammaproteobacteria
, notably
Escherichia
species and
Pseudomonas fluorescens
. Culture growth above the threshold of 10
4
CFU/ml was correlated with increased bacterial DNA burden (
P
< 0.01), decreased community diversity (
P
< 0.05), and increased relative abundance of
Pseudomonas aeruginosa
(
P
< 0.001). We present two case studies in which culture-independent techniques identified a respiratory pathogen missed by culture and clarified whether a cultured “oral flora” species represented a state of acute infection. In summary, we found that bacterial culture of BAL fluid is largely effective in discriminating acute infection from its absence and identified some specific limitations of BAL fluid culture in the diagnosis of pneumonia. We report the first correlation of quantitative BAL fluid culture results with culture-independent evidence of infection.
Endotracheal Aspirate and Bronchoalveolar Lavage Fluid Analysis: Interchangeable Diagnostic Modalities in Suspected Ventilator-Associated Pneumonia?
Authors: Scholte Johannes B. J. , van Dessel Helke A. , Linssen Catharina F. M. , Bergmans Dennis C. J. J. , Savelkoul Paul H. M. , Roekaerts Paul M. H. J. , van Mook Walther N. K. A.
Published: July 2014

Authoritative guidelines state that the diagnosis of ventilator-associated pneumonia (VAP) can be established using either endotracheal aspirate (ETA) or bronchoalveolar lavage fluid (BALF) analysis, thereby suggesting that their results are considered to be in accordance. Therefore, the results of ETA Gram staining and semiquantitative cultures were compared to the results from a paired ETA-BALF analysis. Different thresholds for the positivity of ETAs were assessed. This was a prospective study of all patients who underwent bronchoalveolar lavage for suspected VAP in a 27-bed university intensive care unit during an 8-year period. VAP was diagnosed when ≥2% of the BALF cells contained intracellular organisms and/or when BALF quantitative culture revealed ≥104CFU/ml of potentially pathogenic microorganisms. ETA Gram staining and semiquantitative cultures were compared to the results from paired BALF analysis by Cohen's kappa coefficients. VAP was suspected in 311 patients and diagnosed in 122 (39%) patients. In 288 (93%) patients, the results from the ETA analysis were available for comparison. Depending on the threshold used and the diagnostic modality, VAP incidences varied from 15% to 68%. For the diagnosis of VAP, the most accurate threshold for positivity of ETA semiquantitative cultures was moderate or heavy growth, whereas the optimal threshold for BALF Gram staining was ≥1 microorganisms per high power field. The Cohen's kappa coefficients were 0.22, 0.31, and 0.60 for ETA and paired BALF Gram stains, cultures, and BALF Gram stains, respectively. Since the ETA and BALF Gram stains and cultures agreed only fairly, they are probably not interchangeable for diagnosing VAP.
Cryptic and Rare Aspergillus Species in Brazil: Prevalence in Clinical Samples and
In Vitro
Susceptibility to Triazoles
Authors: Negri C. E. , Gonçalves S. S. , Xafranski H. , Bergamasco M. D. , Aquino V. R. , Castro P. T. O. , Colombo A. L.
Published: July 2014

Aspergillus
spp. are among the most common causes of opportunistic invasive fungal infections in tertiary care hospitals. Little is known about the prevalence and
in vitro
susceptibility of
Aspergillus
species in Latin America, because there are few medical centers able to perform accurate identification at the species level. The purpose of this study was to analyze the distribution of cryptic and rare
Aspergillus
species among clinical samples from 133 patients with suspected aspergillosis admitted in 12 medical centers in Brazil and to analyze the
in vitro
activity of different antifungal drugs. The identification of
Aspergillus
species was performed based on a polyphasic approach, as well as sequencing analysis of the internal transcribed spacer (ITS) region, calmodulin, and β-tubulin genes and phylogenetic analysis when necessary. The
in vitro
susceptibility tests with voriconazole, posaconazole, and itraconazole were performed according to the CLSI M38-A2 document (2008). We demonstrated a high prevalence of cryptic species causing human infection. Only three isolates, representing the species
Aspergillus thermomutatus
,
A. ochraceus
, and
A. calidoustus
, showed less
in vitro
susceptibility to at least one of the triazoles tested. Accurate identifications of
Aspergillus
at the species level and with
in vitro
susceptibility tests are important because some species may present unique resistance patterns against specific antifungal drugs.
Rapid Inactivation of Mycobacterium and Nocardia Species before Identification Using Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry
Authors: Dunne W. Michael , Doing Kirk , Miller Elizabeth , Miller Eric , Moreno Erik , Baghli Mehdi , Mailler Sandrine , Girard Victoria , van Belkum Alex , Deol Parampal
Published: July 2014

The identification of mycobacteria outside biocontainment facilities requires that the organisms first be rendered inactive. Exposure to 70% ethanol (EtOH) either before or after mechanical disruption was evaluated in order to establish a safe, effective, and rapid inactivation protocol that is compatible with identification of
Mycobacterium
and
Nocardia
species using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). A combination of 5 min of bead beating in 70% EtOH followed by a 10-min room temperature incubation period was found to be rapidly bactericidal and provided high-quality spectra compared to spectra obtained directly from growth on solid media. The age of the culture, the stability of the refrigerated or frozen lysates, and freeze-thaw cycles did not adversely impact the quality of the spectra or the identification obtained.