bluuebunny/crossref_metadata_2025 huggingface dataset:
Piccolo Regulates the Dynamic Assembly of Presynaptic F-Actin
Authors: Waites Clarissa L. , Leal-Ortiz Sergio A. , Andlauer Till F. M. , Sigrist Stefan J. , Garner Craig C.
Published: October 2011

Filamentous (F)-actin is a known regulator of the synaptic vesicle (SV) cycle, with roles in SV mobilization, fusion, and endocytosis. However, the molecular pathways that regulate its dynamic assembly within presynaptic boutons remain unclear. In this study, we have used shRNA-mediated knockdown to demonstrate that Piccolo, a multidomain protein of the active zone cytomatrix, is a key regulator of presynaptic F-actin assembly. Boutons lacking Piccolo exhibit enhanced activity-dependent Synapsin1a dispersion and SV exocytosis, and reduced F-actin polymerization and CaMKII recruitment. These phenotypes are rescued by stabilizing F-actin filaments and mimicked by knocking down Profilin2, another regulator of presynaptic F-actin assembly. Importantly, we find that mice with a targeted deletion of exon 14 from thePclogene, reported to lack >95% of Piccolo, continue to express multiple Piccolo isoforms. Furthermore, neurons cultured from these mice exhibit no defects in presynaptic F-actin assembly due to the expression of these isoforms at presynaptic boutons. These data reveal that Piccolo regulates neurotransmitter release by facilitating activity-dependent F-actin assembly and the dynamic recruitment of key signaling molecules into presynaptic boutons, and highlight the need for new genetic models with which to study Piccolo loss of function.
The Effect of Noise Correlations in Populations of Diversely Tuned Neurons
Authors: Ecker Alexander S. , Berens Philipp , Tolias Andreas S. , Bethge Matthias
Published: October 2011

The amount of information encoded by networks of neurons critically depends on the correlation structure of their activity. Neurons with similar stimulus preferences tend to have higher noise correlations than others. In homogeneous populations of neurons, this limited range correlation structure is highly detrimental to the accuracy of a population code. Therefore, reduced spike count correlations under attention, after adaptation, or after learning have been interpreted as evidence for a more efficient population code. Here, we analyze the role of limited range correlations in more realistic, heterogeneous population models. We use Fisher information and maximum-likelihood decoding to show that reduced correlations do not necessarily improve encoding accuracy. In fact, in populations with more than a few hundred neurons, increasing the level of limited range correlations can substantially improve encoding accuracy. We found that this improvement results from a decrease in noise entropy that is associated with increasing correlations if the marginal distributions are unchanged. Surprisingly, for constant noise entropy and in the limit of large populations, the encoding accuracy is independent of both structure and magnitude of noise correlations.
Metabolic Dysfunction Associated with Adiponectin Deficiency Enhances Kainic Acid-Induced Seizure Severity
Authors: Lee Edward B. , Warmann Genevieve , Dhir Ravindra , Ahima Rexford S.
Published: October 2011

Metabolic syndrome has deleterious effects on the CNS, and recent evidence suggests that obesity rates are higher at presentation in children who develop epilepsy. Adiponectin is secreted by adipose tissue and acts in the brain and peripheral organs to regulate glucose and lipid metabolism. Adiponectin deficiency predisposes toward metabolic syndrome, characterized by obesity, insulin resistance, impaired glucose tolerance, hyperlipidemia, and cardiovascular morbidity. To investigate the relationship between metabolic syndrome and seizures, wild-type C57BL/6J and adiponectin knock-out mice were fed a high-fat diet, followed by treatment with low doses of kainic acid to induce seizures. Adiponectin deficiency in mice fed a high-fat diet resulted in greater fat accumulation, impaired glucose tolerance, hyperlipidemia, increased seizure severity, and increased hippocampal pathology. In contrast, there were no adverse effects of adiponectin deficiency on metabolic phenotype or seizure activity in mice fed a normal (low-fat) chow diet. These findings demonstrate that metabolic syndrome modulates the outcome of seizures and brain injury.
KIBRA Polymorphism Is Related to Enhanced Memory and Elevated Hippocampal Processing
Authors: Kauppi Karolina , Nilsson Lars-Göran , Adolfsson Rolf , Eriksson Elias , Nyberg Lars
Published: October 2011

Several studies have linked the KIBRA rs17070145 T polymorphism to superior episodic memory in healthy humans. One study investigated the effect of KIBRA on brain activation patterns (Papassotiropoulos et al., 2006) and observed increased hippocampal activation in noncarriers of the T allele during retrieval. Noncarriers were interpreted to need more hippocampal activation to reach the same performance level as T carriers. Using large behavioral (N= 2230) and fMRI (N= 83) samples, we replicated the KIBRA effect on episodic memory performance, but found increased hippocampal activation in T carriers during episodic retrieval. There was no evidence of compensatory brain activation in noncarriers within the hippocampal region. In the main fMRI sample, T carriers performed better than noncarriers during scanning but, importantly, the difference in hippocampus activation remained afterpost hocmatching according to performance, sex, and age (N= 64). These findings link enhanced memory performance in KIBRA T allele carriers to elevated hippocampal functioning, rather than to neural compensation in noncarriers.
Mutant PKCγ in Spinocerebellar Ataxia Type 14 Disrupts Synapse Elimination and Long-Term Depression in Purkinje CellsIn Vivo
Authors: Shuvaev Anton N. , Horiuchi Hajime , Seki Takahiro , Goenawan Hanna , Irie Tomohiko , Iizuka Akira , Sakai Norio , Hirai Hirokazu
Published: October 2011

Cerebellar Purkinje cells (PCs) express a large amount of the γ isoform of protein kinase C (PKCγ) and a modest level of PKCα. The PKCγ is involved in the pruning of climbing fiber (CF) synapses from developing PCs, and PKCα plays a critical role in long-term depression (LTD) at parallel fiber (PF)-PC synapses. Moreover, the PKC signaling in PCs negatively modulates the nonselective transient receptor potential cation channel type 3 (TRPC3), the opening of which elicits slow EPSCs at PF-PC synapses. Autosomal dominant spinocerebellar ataxia type 14 (SCA14) is caused by mutations in PKCγ. To clarify the pathology of this disorder, mutant (S119P) PKCγ tagged with GFP was lentivirally expressed in developing and mature mouse PCsin vivo, and the effects were assessed 3 weeks after the injection. Mutant PKCγ-GFP aggregated in PCs without signs of degeneration. Electrophysiology results showed impaired pruning of CF synapses from developing PCs, failure of LTD expression, and increases in slow EPSC amplitude. We also found that mutant PKCγ colocalized with wild-type PKCγ, which suggests that mutant PKCγ acts in a dominant-negative manner on wild-type PKCγ. In contrast, PKCα did not colocalize with mutant PKCγ. The membrane residence time of PKCα after depolarization-induced translocation, however, was significantly decreased when it was present with the mutant PKCγ construct. These results suggest that mutant PKCγ in PCs of SCA14 patients could differentially impair the membrane translocation kinetics of wild-type γ and α PKCs, which would disrupt synapse pruning, synaptic plasticity, and synaptic transmission.
Bridging the Gap: Addressing Challenges toward Improvement of Cleft Teamwork in a Tertiary Care Center in North India: A Pilot Study
Authors: Moghe Gayatri , Mauli Simratvir , Thomas Abi , Obed Vijay A.E.
Published: October 2011

Aim

The aim of this study was the initiation of systematic data collection so as to improve the capacity for outcome measurement after cleft repair. Also, a clinical audit was done for evaluation of the process and assessment of outcomes of cleft care.

Design and Setting

A questionnaire-based survey and outcome assessment was carried out over a 1-year period from March 2008 to February 2009 at the combined outpatient cleft clinic of a tertiary care center in India.

Patients and Participants

Data collection (basic demographic and environmental information) was done twice a week throughout the year by students from the Department of Pediatric Dentistry, at the outpatient cleft clinic.

Results

A total of 68 completed cleft lip and palate registry forms, from which all the information was available, were analyzed. There was a skewed sex ratio, with a higher preponderance of boys seeking treatment. Of affected males, 19.1% were between 2 and 5 years of age when they first reported to the cleft clinic. Surprisingly, no bilateral clefts of lip, unilateral cleft lip (right) and unilateral cleft lip and palate (right) were observed in girls. Oral health was poor in 74% of patients; among the dental referrals only 26% could be recruited for orthodontics with a reasonably good prognosis.

Conclusions

Poverty, illiteracy, and superstitions prevent an average patient from India from receiving multidisciplinary cleft care. This emphasizes the need to create systems that suit the needs of our target patients.
Effect of Nutrients and Smoke Solutions on Seed Germination and Seedling Growth of Tropical Soda Apple (Solanum viarum)
Authors: Kandari Laxman S. , Kulkarni Manoj G. , Van Staden Johannes
Published: October 2011

Solanum viarum, commonly known as tropical soda apple (TSA), is native to Brazil and Argentina but has become a harmful weed in many countries with tropical climates. This study was conducted to reassess the seed biology of TSA found in South Africa. Cold stratification (14 d), acid scarification (20% H2SO4for 5 min), and sandpaper scarification (30 s) significantly improved percentage germination when compared to the control. The highest germination (99.5%) was achieved when seeds were germinated in 50% Hoagland's nutrient solution (HS). The lowest germination (66%) was recorded in the absence of phosphorus (P) under alternating light conditions. HS without nitrogen (N) completely inhibited seed germination of TSA under constant light conditions. These findings are useful in controlling TSA by amending the levels of N and P in soils. Seed germination of TSA was significantly enhanced by different concentrations of smoke-water and butenolide solution. Smoke-water dilution of 1:500 v/v and butenolide concentration of 10−8M showed the highest seedling vigor indices (6,688 and 6,666, respectively) in comparison to the control (1,251) and gibberellic acid (GA3) concentrations (< 5,327). These findings suggest that germination of seeds or seedbanks of TSA might be successfully stimulated using smoke solutions. Subsequently, patches of seedlings emerging after treatment can be mechanically uprooted to reduce the infestation of TSA. However, justifying this with field trials is essential.
Competitive Effects of Glyphosate-Resistant and Glyphosate-Susceptible Horseweed (Conyza canadensis) on Young Grapevines (Vitis vinifera)
Authors: Alcorta Marisa , Fidelibus Matthew W. , Steenwerth Kerri L. , Shrestha Anil
Published: October 2011

Horseweed is a common pest in vineyards of the San Joaquin Valley (SJV) of California. Interest in controlling this weed has increased with the recent discovery of a glyphosate-resistant (GR) biotype that has been observed to be more vigorous than a glyphosate-susceptible (GS) biotype in the SJV. However, the impact that either biotype may have on grapevine growth has not been assessed. Therefore, two glasshouse experiments were conducted to characterize the competitiveness of GR and GS horseweed biotypes from the SJV with young grapevines. ‘Syrah’ grapevines grafted to Freedom rootstocks were planted in 8-L plastic pots, alone, or with a single GR or GS horseweed. Additional GR and GS horseweeds were also planted separately in individual pots, and all plants were grown for 14 and 16 wk in 2006 and 2007, respectively. Grapevines grown with either biotype of the weed produced fewer leaves and amassed approximately 20% less dry mass (DM) than vines grown alone. The GR biotype reduced grapevine stem DM and length by 30%, but the GS biotype did not. The GR biotype accumulated more than twice the DM as the GS biotype, whether in competition with grapevine or not. Grapevines reduced the total leaf number of both horseweed biotypes by almost 50% and aboveground DM of GR and GS biotypes by 50 and 75%, respectively. These preliminary findings indicate that competition from horseweed can substantially reduce the growth of young grapevines and that the GR biotype may be more competitive than the GS biotype.
The Effect of Rotation and In-Crop Weed Management on the Germinable Weed Seedbank after 10 Years
Authors: Gulden Robert H. , Lewis Derek W. , Froese Jane C. , Van Acker Rene C. , Martens Gary B. , Entz Martin H. , Derksen Doug A. , Bell Lindsay W.
Published: October 2011

Agricultural production systems that reduce the use of in-crop herbicides could greatly reduce risks of environmental damage and the development of herbicide-resistant weeds. Few studies have investigated the long-term effects of in-crop herbicide omissions on weed seedbank community size and structure. A crop-rotation study was sampled 10 yr after a strictly annual rotation and an annual/perennial rotation were exposed to different in-crop herbicide omission treatments. In-crop herbicides were applied either in all annual crops (control), omitted from oats only, or omitted from both flax and oats. Seedbank densities were greatest when in-crop herbicides were omitted from flax and oats, and this treatment also reduced crop yield. Shannon-Wiener diversity differed among crops in the annual crop rotation and among herbicide omission treatments in the perennial rotation. Herbicide omissions changed the weed-community structure in flax and in wheat and canola crops in the annual rotation enough to warrant alternate control methods in some treatments. The magnitude of the effects on the seedbank parameters depended largely on the competitive ability of the crop in which herbicides were omitted. No yield response to omitting herbicides in oats indicated that standard weed management practices have reduced weed populations below yield-loss thresholds.
Buckwheat Residue Effects on Emergence and Growth of Weeds in Winter-Wheat (Triticum aestivum) Cropping Systems
Authors: Kumar Virender , Brainard Daniel C. , Bellinder Robin R. , Hahn Russell R.
Published: October 2011

Field and pot studies were conducted in Central New York to determine the potential weed-management benefits of a buckwheat cover crop grown before winter wheat. Specific objectives were to determine buckwheat residue effects on (1) emergence and growth of winter annual weeds; (2) wheat establishment and yield; and (3) emergence of summer annual weeds in the spring following overwinter seed burial. In a field study, buckwheat was sown at two timings (July or August), mowed, and either incorporated or left on the soil surface. Winter wheat was drilled into buckwheat residue in September and weed and crop growth were monitored. In a complementary pot study, four winter annual weeds were sown in soil removed from buckwheat and bare-soil plots at 0 or 15 d after incorporation and monitored for emergence and early growth. To assess buckwheat residue effects on spring emergence from overwintering seeds, seeds of three weed species were buried in buckwheat residue and bare-soil plots in the fall, exhumed in April, and evaluated for emergence. To investigate the mechanism for possible effects of buckwheat residue on overwintering seeds, two levels each of seed treatment (none or fungicide) and fertilization (none or 170 kg ha−1) were applied before burial. Buckwheat residue had no negative effect on wheat yields but suppressed emergence (22 to 72%) and growth (0 to 95%) of winter annual weeds, although effects were often small and inconsistent. Buckwheat residue had no effect on the emergence of buried weed seeds in spring. However, fungicide treatment enhanced the emergence of Powell amaranth seeds by 12.5 to 25.5% and of barnyardgrass seeds by 0 to 12%. Our results suggest that buckwheat residue can contribute to weed management in wheat cropping systems, but that further studies investigating the mechanistic basis for the inconsistent selective effects of buckwheat residue on weeds are needed before buckwheat use can be optimized.
Climate Change and the Potential Global Distribution of Serrated Tussock (Nassella trichotoma)
Authors: Watt Michael S. , Kriticos Darren J. , Lamoureaux Shona L. , Bourdôt Graeme W.
Published: October 2011

We used the process-oriented niche model CLIMEX to estimate the potential global distribution of serrated tussock under projected future climates. Serrated tussock is a drought-tolerant, wind- and human-dispersed grass of South American origin that has invaded pastures in Australia, Europe, New Zealand, and South Africa. The likely effect of climate change on its potential global distribution was assessed by applying six climate-change scenarios to a previously developed model. The projections of climatic suitability under the current climate revealed considerable scope for spread, with the most suitable areas occurring adjacent to existing naturalized populations in Australia, New Zealand, and Western Europe. Under future climates, projected to the 2080s, the land area suitable for serrated tussock contracts globally between 20 and 27%. Changes in projected potential area under the six scenarios were very similar in all geographical regions apart from North America and New Zealand, where the projections range from little change or contraction under the National Center for Atmospheric Research (NCAR) and Centre for Climate Research (MIROC) global climate models (GCMs) to expansion under the Commonwealth Scientific and Industrial Research Organisation (CSIRO) GCM. Elsewhere, contractions occur in Australia, Asia, South America, and Africa under all six future climate scenarios. By contrast, for Europe, the area climatically suitable for serrated tussock increases under all six scenarios (average increase 47%) through expansions into eastern European countries that are currently unsuitable and through increases in the suitable area in England, Ireland, and Denmark. Since pastoralism is a dominant land use in these regions of Europe, a prudent biosecurity strategy would be to contain the nascent foci of serrated tussock in southern France, along the west coast of Italy, and in the United Kingdom. This strategy could consist of a set of policies to limit human-assisted dispersal of the species' seeds and to reduce wind-borne spread through cultural control of the plant.
Manuka Oil, A Natural Herbicide with Preemergence Activity
Authors: Dayan Franck E. , Howell J'Lynn , Marais Jannie P. , Ferreira Daneel , Koivunen Marja
Published: October 2011

Natural herbicides approved in organic agriculture are primarily nonselective burn-down essential oils applied POST. Multiple applications are often required due to their low efficacy. To address this problem, the in vivo herbicidal activity of manuka oil, the essential oil distilled from manuka tree (Leptospermum scopariumJ.R. and G. Forst), was tested on selected broadleaf and grass weeds. While manuka oil exhibited good POST activity when applied in combination with a commercial lemongrass oil–based herbicide, it ultimately demonstrated interesting PRE activity, providing control of large crabgrass seedlings at a rate of 3 L ha−1. Manuka oil and its main active ingredient, leptospermone, were stable in soil for up to 7 d and had half-lives of 18 and 15 d, respectively. The systemic activity of manuka oil addresses many of the current limitations associated with natural herbicides. Additionally, its soil persistence opens up a multitude of new possibilities for the use of manuka oil as a tool for weed management and may be a potential bridge between traditional and organic agriculture.
Fate of Glyphosate-Resistant Giant Ragweed (Ambrosia trifida) in the Presence and Absence of Glyphosate
Authors: Brabham Chad B. , Gerber Corey K. , Johnson William G.
Published: October 2011

Glyphosate-resistant giant ragweed has become an increasing problem, and the potential spread of these biotypes is a threat to production agriculture and to the long-term utility of glyphosate and glyphosate-resistant crops. The fate of glyphosate resistance in a giant ragweed population is dependent on the fitness of the resistant biotype. Our objective was to determine the fitness of glyphosate-resistant giant ragweed in the absence and presence of glyphosate. We compared the growth and seed production of glyphosate-resistant (GR) and glyphosate-susceptible (GS) giant ragweed under field conditions in the absence of glyphosate. A greenhouse study was also conducted to determine the survival of GR and GS giant ragweed and their open-pollinated progeny from the field study under glyphosate-induced selection pressure. In the absence of glyphosate, GR giant ragweed displayed rapid, early season growth, but 50 d after planting, the biotypes were similar in height, shoot weight, and leaf area. During reproduction, the GR biotype flowered earlier and produced 25% less seed than the GS biotype. In the presence of glyphosate, an outcrossing rate of 31% was detected between GR and GS biotypes because 61% of progeny were resistant to glyphosate at 840 g ae ha−1. A second application 14 d later at 2,520 g ae ha−1completely removed the GS alleles from the population, whereas several homozygous and heterozygous GR plants survived and produced seed. These results indicate GR will persist in the population when subjected to glyphosate and that glyphosate resistance in giant ragweed has the potential to spread rapidly in our current agricultural ecosystem.
Evolution of Resistance to Auxinic Herbicides: Historical Perspectives, Mechanisms of Resistance, and Implications for Broadleaf Weed Management in Agronomic Crops
Authors: Mithila J. , Hall J. Christopher , Johnson William G. , Kelley Kevin B. , Riechers Dean E.
Published: October 2011

Auxinic herbicides are widely used for control of broadleaf weeds in cereal crops and turfgrass. These herbicides are structurally similar to the natural plant hormone auxin, and induce several of the same physiological and biochemical responses at low concentrations. After several decades of research to understand the auxin signal transduction pathway, the receptors for auxin binding and resultant biochemical and physiological responses have recently been discovered in plants. However, the precise mode of action for the auxinic herbicides is not completely understood despite their extensive use in agriculture for over six decades. Auxinic herbicide-resistant weed biotypes offer excellent model species for uncovering the mode of action as well as resistance to these compounds. Compared with other herbicide families, the incidence of resistance to auxinic herbicides is relatively low, with only 29 auxinic herbicide-resistant weed species discovered to date. The relatively low incidence of resistance to auxinic herbicides has been attributed to the presence of rare alleles imparting resistance in natural weed populations, the potential for fitness penalties due to mutations conferring resistance in weeds, and the complex mode of action of auxinic herbicides in sensitive dicot plants. This review discusses recent advances in the auxin signal transduction pathway and its relation to auxinic herbicide mode of action. Furthermore, comprehensive information about the genetics and inheritance of auxinic herbicide resistance and case studies examining mechanisms of resistance in auxinic herbicide-resistant broadleaf weed biotypes are provided. Within the context of recent findings pertaining to auxin biology and mechanisms of resistance to auxinic herbicides, agronomic implications of the evolution of resistance to these herbicides are discussed in light of new auxinic herbicide-resistant crops that will be commercialized in the near future.
Hydraulic and treatment performance of pervious pavements under variable drying and wetting regimes
Authors: Yong C. F. , Deletic A. , Fletcher T. D. , Grace M. R.
Published: October 2011

Pervious pavements are an effective stormwater treatment technology. However, their performance under variable drying and wetting conditions have yet to be tested, particularly under a continuous time scale. This paper reports on the clogging behaviour and pollutant removal efficiency of three pervious pavement types over 26 accelerated years. These pavements were monolithic porous asphalt (PA), Permapave (PP) and modular Hydrapave (HP). Over a cycle of 13 days, the period of which was equivalent to the average annual Brisbane, Australia rainfall (1,200 mm), the pavements were randomly dosed with four different flows. Drying events of 3 h duration were simulated during each flow. Inflow and outflow samples were collected and analysed for Total Suspended Solids (TSS), Total Phosphorus (TP) and Total Nitrogen (TN). To evaluate the rate of clogging, a 1 in 5 year Brisbane storm event was simulated in the 6th, 8th, 12th, 16th, 20th and 24th week. Under normal dosing conditions, none of the pavements showed signs of clogging even after 15 years. However, under storm conditions, both PA and HP started to clog after 12 years, while PP showed no signs of clogging after 26 years. The drying and various flow events showed no effects in TSS removal, with all systems achieving a removal of approximately 100%. The average TP removal was 20% for all flows except for low flow, which had a significant amount of leaching over time. Leaching from TN was also observed during all flows except high flow. The TSS, TP and TN results observed during storm events were similar to that of high flow.
Mechanism of adsorption of ferric iron by extracellular polymeric substances (EPS) from a bacterium Acidiphilium sp.
Authors: Tapia J. M. , Muñoz J. A. , González F. , Blázquez M. L. , Ballester A.
Published: October 2011

The aim of this study was to assess the sorption of Fe(III) by extracellular polymeric substances (EPS) of the Acidiphilium 3.2Sup(5) bacterium, which has promising properties for use in microbial fuel cells (MFC). The EPS of A. 3.2Sup(5) was extracted using EDTA. The sorption isotherms were determined using aliquots of purified EPS. The exosubstances loaded with metal were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy (FTIR). The sorption uptake approaches to 536.1 ± 26.6 mg Fe(III) (g EPS)−1 at an initial ferric concentration of 2.0 g l−1. The sorption of Fe(III) by EPS can be fitted to the Freundlich model. The sorption process produces hydrated iron (III) oxalate [Fe(OH)(C2O4) × 2H2O] by a reversible reaction (log K = 1.06 ± 0.16), indicating that a shift in the sorption of the cation can be easily achieved. Know the magnitude and form of iron sorption by EPS in MFC can foresee the potential impact on the metabolism of iron-reducing and iron-oxidazing bacteria and, therefore, on the feasibility of the system.
Post Treatment Process and Selective Laser Sintering Mechanism of Polymer-Coated Mo Powder
Authors: Liu Bin , Bai Peikang , Li Yuxin
Published: October 2011

A novel preparing method of polymer-coated molybdenum powder was presented. A type of multi-component
polymer-coated molybdenum powder was chosen for selective laser sintering. The effect of the process parameters on the
part's characteristics is investigated. Based on our study for dynamic laser sintering process of polymer-coated
molybdenum powder, its laser sintering mechanism was reported as follows: at the early stage of laser sintering, the
viscous flow is the major mechanism; during the laser sintering, the melting/solidification is the major mechanism.
Furthermore, a model corresponding to the mechanism was discussed schematically, which could be used to explain the
material migrating mode during laser sintering process. The laser sintering experiments of polymer-coated Mo powder
was conducted in the self-developed laser sintering machine, and optimized parameters have been acquired. At last, the
post treatment process of laser sintered parts has been developed and refractory metal parts of Mo/Cu composites are
gained. The post treatment process includes debinding, high temperature sintering and melting infiltration, which is
sintering framework-Mo by high temperature combining with Cu impregnation method. It is found that the mechanical
properties of parts have been greatly improved after the post treatment process.
A Sequential Phase 2b Trial Design for Evaluating Vaccine Efficacy and Immune Correlates for Multiple HIV Vaccine Regimens
Authors: Gilbert Peter B. , Grove Douglas , Gabriel Erin , Huang Ying , Gray Glenda , Hammer Scott M. , Buchbinder Susan P. , Kublin James , Corey Lawrence , Self Steven G.
Published: October 2011

Five preventative HIV vaccine efficacy trials have been conducted over the last 12 years, all of which evaluated vaccine efficacy (VE) to prevent HIV infection for a single vaccine regimen versus placebo. Now that one of these trials has supported partial VE of a prime-boost vaccine regimen, there is interest in conducting efficacy trials that simultaneously evaluate multiple prime-boost vaccine regimens against a shared placebo group in the same geographic region, for accelerating the pace of vaccine development. This article proposes such a design, which has main objectives (1) to evaluate VE of each regimen versus placebo against HIV exposures occurring near the time of the immunizations; (2) to evaluate durability of VE for each vaccine regimen showing reliable evidence for positive VE; (3) to expeditiously evaluate the immune correlates of protection if any vaccine regimen shows reliable evidence for positive VE; and (4) to compare VE among the vaccine regimens. The design uses sequential monitoring for the events of vaccine harm, non-efficacy, and high efficacy, selected to weed out poor vaccines as rapidly as possible while guarding against prematurely weeding out a vaccine that does not confer efficacy until most of the immunizations are received. The evaluation of the design shows that testing multiple vaccine regimens is important for providing a well-powered assessment of the correlation of vaccine-induced immune responses with HIV infection, and is critically important for providing a reasonably powered assessment of the value of identified correlates as surrogate endpoints for HIV infection.
Editorial Note
Authors: Kovarik Zrinka
Published: October 2011

Editorial Note
High-Risk Biodegradable Waste Processing By Alkaline Hydrolysis
Authors: Kalambura Sanja , Voća Neven , Krička Tajana , Šindrak Zoran , Špehar Ana , Kalambura Dejan
Published: October 2011

High-Risk Biodegradable Waste Processing By Alkaline Hydrolysis

Biodegradable waste is by definition degraded by other living organisms. Every day, meat industry produces large amounts of a specific type of biodegradable waste called slaughterhouse waste. Traditionally in Europe, this waste is recycled in rendering plants which produce meat and bone meal and fat. However, feeding animals with meat and bone meal has been banned since the outbreaks of bovine spongiform encephalopathy (BSE). In consequence, new slaughterhouse waste processing technologies have been developed, and animal wastes have now been used for energy production. Certain parts of this waste, such as brains and spinal cord, are deemed high-risk substances, because they may be infected with prions. Their treatment is therefore possible only in strictly controlled conditions. One of the methods which seems to bear acceptable health risk is alkaline hydrolysis. This paper presents the results of an alkaline hydrolysis efficiency study. It also proposes reuse of the obtained material as organic fertiliser, as is suggested by the analytical comparison between meat and bone meal and hydrolysate.
Risk Assessment of Human Exposure to Pesticides in Food
Authors: Knežević Zorka , Serdar Maja
Published: October 2011

Procjena rizika od izloženosti ljudi pesticidima unesenim hranom

U ovome preglednom radu prikazane su metode procjene rizika od akutne i kronične izloženosti ljudi ostacima pesticida unesenih hranom. U hrani su često prisutni ostaci više različitih pesticida. Međutim rizik od istodobne izloženosti ostacima različitih pesticida nije moguće utvrditi jer trenutačno ne postoji međunarodno prihvaćeni postupak kumulativne procjene rizika. Stoga se procjena rizika temelji na toksikološkoj procjeni pojedinačnog spoja u određenoj vrsti hrane. Za izračun akutnog unosa najčešće se upotrebljava tzv. međunarodna procjena kratkoročnog unosa (engl. international estimation of short-term intake, IESTI). Model izračuna IESTI temelji se na tzv. metodi najgoreg scenarija uz pretpostavke da će osoba u kratkom vremenu konzumirati veliku količinu hrane koja sadržava najveći određeni maseni udio pesticida te uzimajući u obzir i nehomogenost distribucije ostataka pesticida u hrani. Kronična izloženost ostacima pesticida procjenjuje se uz primjenu tzv. determinističkog modela koji je analogan izračunu maksimalnoga dnevnog unosa.
Cytotoxic and Genotoxic Effects of the Quercetin/Lanthanum Complex on Human Cervical Carcinoma Cells In Vitro
Authors: Durgo Ksenija , Halec Ivana , Šola Ivana , Franekić Jasna
Published: October 2011

Cytotoxic and Genotoxic Effects of the Quercetin/Lanthanum Complex on Human Cervical Carcinoma CellsIn Vitro

Quercetin is the main flavonoid in diet with a potential in the treatment of cancer, cardiovascular, and neurodegenerative diseases. Due to its specific planar chemical structure, quercetin readily forms chelates with metal ions. Complexes of bioactive compounds and metal ions such as lanthanum often show strong cytotoxic and antitumour properties. The aim of this study was to compare the genotoxic effects of the quercetin/lanthanum complex on human cervical carcinoma cells with compare it to the effects of free ligands, quercetin, and lanthanum alone. The quercetin/lanthanum complex showed considerable cytotoxicity in the concentration range of (100 to 1000) mmol mL-1and exposure time of three hours. The complex also induced a dose-dependent pro-oxidative effects and the formation of single-strand and double-strand DNA breaks. Although we obtained promising results on the cell level, future experiments should answer whether the quercetin/lanthanum complex is cancer-specific and stable enough in physiological conditions to make a potential new antitumour drug.
Side Effects of Adjuvant Radiotherapy in Men with Testicular Seminoma Stage I
Authors: Gamulin Marija , Grgić Mislav , Bišof Vesna
Published: October 2011

Side Effects of Adjuvant Radiotherapy in Men with Testicular Seminoma Stage I

In this study we followed up the side effects of adjuvant radiotherapy in patients with testicular seminoma stage I over a period from 13 to 84 months (median 28 months). The most frequent side effects during radiotherapy were gastrointestinal (nausea/vomiting), psychological, cognitive, and minor sexual problems.

The reported side effects were treated by antiemetics and anxiolytics. After radiotherapy, the side effects persisted in 6 % of patients, but only a few of them required additional treatment. Healthy children were born to 76 % of patients in the 18 to 39 years age group. This study shows that adjuvant radiotherapy of the para-aortic lymph nodes with the total dosage of 24 Gy in 16 daily fractions administered to testicular seminoma patients causes acceptable side effects, does not adversely affect quality of life and fertility, if the approach to treatment is individual and family consulting is provided. This makes adjuvant radiotherapy of the para-aortic lymph nodes an acceptable treatment for testicular seminoma stage I patients.
Influence of Hamstring Muscles Extensibility on Spinal Curvatures and Pelvic Tilt in Highly Trained Cyclists
Authors: Muyor José , Alacid Fernando , López-Miñarro Pedro
Published: October 2011

Influence of Hamstring Muscles Extensibility on Spinal Curvatures and Pelvic Tilt in Highly Trained Cyclists

The purpose of this study was to determine the influence of hamstring muscles extensibility in standing, maximal trunk flexion with knees extended and on the bicycle in lower handlebar-hands position of highly trained cyclists. Ninety-six cyclists were recruited for the study (mean ± SD, age: 30.36 ± 5.98 years). Sagittal spinal curvatures and pelvic tilt were measured in the standing position, maximal trunk flexion with knees extended (sit-and-reach test) and while sitting on a bicycle in lower handlebar-hand position using a Spinal Mouse system. Hamstring muscles extensibility was determined in both legs by passive straight leg raise test (PSLR). The sample was divided into three groups according to PSLR angle: (1) reduced extensibility (PSLR < 80º; n = 30), (2) moderate hamstring extensibility group (PSLR = 80º; - 90º; n = 35), and (3) high hamstring extensibility (PSLR = > 90º; n = 31). ANOVA analysis showed significant differences among groups for thoracic (p < 0.001) and pelvic tilt (p < 0.001) angles in the sit-andreach test. No differences were found between groups for standing and on the bicycle position. Post hoc analysis showed significant differences in all pairwise comparisons for thoracic angle (p < 0.01) and pelvic angle (p < 0.001) in the sit-and-reach test. No differences were found in lumbar angle in any posture. In conclusion, the hamstring muscles extensibility influence the thoracic and pelvic postures when maximal trunk flexion with knees extended is performed, but not when cyclists are seated on their bicycles
Reconstruction Error of Calibration Volume's Coordinates for 3D Swimming Kinematics
Authors: Figueiredo Pedro , Machado Leandro , Vilas-Boas João , Fernandes Ricardo
Published: October 2011

Reconstruction Error of Calibration Volume's Coordinates for 3D Swimming Kinematics

The aim of this study was to investigate the accuracy and reliability of above and underwater 3D reconstruction of three calibration volumes with different control points disposal (#1 - on vertical and horizontal rods; #2 - on vertical and horizontal rods and facets; #3 - on crossed horizontal rods). Each calibration volume (3 × 2 × 3 m) was positioned in a 25 m swimming pool (half above and half below the water surface) and recorded with four underwater and two above water synchronised cameras (50 Hz). Reconstruction accuracy was determined calculating the RMS error of twelve validation points. The standard deviation across all digitisation of the same marker was used for assessing the reliability estimation. Comparison among different number of control points showed that the set of 24 points produced the most accurate results. The volume #2 presented higher accuracy (RMS errors: 5.86 and 3.59 mm for × axis, 3.45 and 3.11 mm for y axis and 4.38 and 4.00 mm for z axis, considering under and above water, respectively) and reliability (SD: underwater cameras ± [0.2; 0.6] mm; above water cameras ± [0.2; 0.3] mm) that may be considered suitable for 3D swimming kinematic analysis. Results revealed that RMS error was greater during underwater analysis, possibly due to refraction.
Effects of Ramadan Fasting on Body Composition, Aerobic Performance and Lactate, Heart Rate and Perceptual Responses in Young Soccer Players
Authors: Güvenç Alpay
Published: October 2011

Effects of Ramadan Fasting on Body Composition, Aerobic Performance and Lactate, Heart Rate and Perceptual Responses in Young Soccer Players

The purpose of this study was to examine the effects of Ramadan fasting on body composition, aerobic exercise performance and blood lactate, heart rate and perceived exertion in regularly trained young soccer players. Sixteen male soccer players participated in this study. Mean age, stature, body mass and training age of the players were 17.4±1.2 years, 175.4±3.6 cm, 69.6±4.3 kg and 5.1±1.3 years, respectively. During the Ramadan period, all subjects voluntarily chose to follow the fasting guidelines and abstained from eating and drinking from sunrise to sunset. Body composition, hydration status, dietary intake and sleep duration were assessed on four occasions: before Ramadan, at the beginning of Ramadan, at the end of Ramadan and 2 weeks after the end of Ramadan. On each occasion, aerobic exercise performance and blood lactate, heart rate and rating of perceived exertion responses of players were also determined during an incremental running test. Repeated measures of ANOVA revealed that body mass, percentage of body fat, fat-free mass, hydration status, daily sleeping time and daily energy and macronutrient intake of players did not vary significantly throughout the study period (p>0.05). However, players experienced a small but significant decrease in skinfold thicknesses over the course of the study (p<0.05). Although ratings of perceived exertion at submaximal workloads increased during Ramadan (p<0.05), blood lactate and heart rate responses had decreased by the end of Ramadan (p<0.05). In line with these changes, peak running performance and running velocity at anaerobic threshold also improved by the end of Ramadan (p<0.05). Improvements in aerobic exercise performance with time were probably due to the effects of pre-season training program that was performed after the break of the fast (Iftar) during the month of Ramadan. The results of the present study suggest that if regular training regimen, body fluid balance, daily energy intake and sleep duration are maintained as before Ramadan, Ramadan fasting does not have detrimental effects on aerobic exercise performance or body composition in young soccer players.
The Effects of 24 weeks of Resistance Training with Simultaneous Elastic and Free Weight Loading on Muscular Performance of Novice Lifters
Authors: Shoepe Todd , Ramirez David , Rovetti Robert , Kohler David , Almstedt Hawley
Published: October 2011

The Effects of 24 weeks of Resistance Training with Simultaneous Elastic and Free Weight Loading on Muscular Performance of Novice Lifters

The purpose of this investigation was to assess the effectiveness of variable resistance as provided through elastic plus free weight techniques in college aged males and females. Twenty novice lifters were randomly assigned to a traditional free weight only (6 males and 5 females) or elastic band plus free weight group (5 males and 5 females) and 9 more normally active controls (5 males and 4 females), were recruited to maintain normal activity for the duration of the study. No differences existed between control, free weight and elastic band at baseline for age, body height, body mass, body mass index, and body fat percentage. One-repetition maximums were performed for squat and bench press while both strength and power were assessed using isokinetic dynamometry. Elastic groups and free-weight groups completed 24 weeks of whole body, periodized, high intensity resistance (65-95% of one-repetition maximum) training three times/week. Training programs were identical except that the elastic group trained the barbell squat, bench press and stiff-legged deadlift with 20-35% of their total prescribed training loads coming from band resistance (assessed at the top of the range of motion) with the remainder from free weight resistance. A mixed-model analysis revealed that peak torque, average power and one-repetition maximums for squat were significantly greater after training for the elastic group compared to the control (p<0.05). In addition, the free weight group also showed significantly greater improvements over the control in peak torque and one-repetition maximums for squat and bench press. No significant differences were observed between the elastic band and free weight groups. Combined variable elastic band plus free weight exercises are effective at increasing strength and power similar to free-weights alone in novice college aged males and females. However, due to complexity in set-up and load assignment elastic adoption by novice lifters in an unsupervised situation is not advised.
Retesting The Validity Of A Specific Field Test For Judo Training
Authors: Santos Luis , González Vicente , Iscar Marta , Brime Juan , Fernández-Río Javier , Rodríguez Blanca , Montoliu Mª
Published: October 2011

Retesting The Validity Of A Specific Field Test For Judo Training

The main goal of this research project was to retest the validity of a specifically designed judo field test (Santos Test) in a different group of judokas. Eight (n=8) national-level male judokas underwent laboratory and field testing. The mean data (mean +/- SD) obtained in the laboratory tests was: HRmax: 200 ± 4.0 beats × min-1, VO2 max: 52.8 ± 7.9 ± ml × kg-1 × min-1, lactate max: 12 ± 2.5 mmol × l-1, HR at the anaerobic threshold: 174.2 ± 9.4 beats × min-1, percentage of maximum heart rate at which the anaerobic threshold appears: 87 ± 3.6 %, lactate threshold: 4.0 ± 0.2 mmol × l-1, and RPE: 17.2 ± 1.0. The mean data obtained in the field test (Santos) was: HRmax: 201.3 ± 4.1 beats × min-1, VO2 max: 55.6 ± 5.8 ml × kg-1 × min-1, lactate max: 15.6 ± 2.8 mmol × l-1, HR at the anaerobic threshold: 173.2 ± 4.3 beats × min-1, percentage of maximum heart rate at which the anaerobic threshold appears: 86 ± 2.5 %, lactate threshold: 4.0 ± 0.2 mmol × l-1, and RPE: 16.7 ± 1.0. There were no significant differences between the data obtained on both tests in any of the parameters, except for maximum lactate concentration. Therefore, the Santos test can be considered a valid tool specific for judo training.
Strength Training and Detraining in Different Populations: Case Studies
Authors: Marques Mário , Zajac Adam , Pereira Ana , Costa Aldo
Published: October 2011

Strength Training and Detraining in Different Populations: Case Studies

Many researchers have demonstrated that a specific strength training program can improve maximal strength and, the rate of force production, reduce the incidence of muscle-skeletal injury, and contribute to faster injury recovery times, thereby minimizing the number of missed practice sessions or competitions. Yet, to our best knowledge, there is no apparent consensus on the appropriate method of muscle strength and power training to enhance performance in distinct populations groups. Interruptions in training process because of illness, injury, holidays, post-season break or other factors are normal situations in any kind of sport. However, the detraining period and its consequences are not well reported in sports literature, and namely during puberty. Therefore, the aim of this paper was to discuss several case studies concerning different populations such us physical students, age-swimming competitors and elite power athletes.
The Importance of Movement Velocity as a Measure to Control Resistance Training Intensity
Authors: González-Badillo Juan , Marques Mário , Sánchez-Medina Luis
Published: October 2011

The Importance of Movement Velocity as a Measure to Control Resistance Training Intensity

Configuration of the exercise stimulus in resitance training has been traditionally associated with a combination of the so-called ‘acute resistance exercise variables’ (exercise type and order, loading, number of repetitions and sets, rests duration and movement velocity). During typical resistance exercise in isoinertial conditions, and assuming every repetition is performed with maximal voluntary effort, velocity unintentionally declines as fatigue develops. However, few studies analyzing the response to different resitance training schemes have described changes in repetition velocity or power. It thus seems necessary to conduct more research using models of fatigue that analyze the reduction in mechanical variables such as force, velocity and power output over repeated dynamic contractions in actual training or competition settings. Thus, the aim of this paper was to discuss the importance of movement velocity concerning control training intensity.