bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimation of mouse fetal weight by ultrasonography: application from clinic to laboratory
Authors: Nguyen Thang M , Nakamura Hitomi , Wakabayashi Atsuko , Kanagawa Takeshi , Koyama Shinsuke , Tsutsui Tateki , Hamasaki Toshimitsu , Kimura Tadashi
Published: June 2012

Ultrasonographic assessment of fetal growth to estimate fetal weight has been widely used in clinical obstetrics but not in laboratory mice. Even though it is important to assess fetal growth abnormalities for gene-targeting studies using mice, there have been no reports of accurately estimated fetal weight using fetal biometric parameters in mice. The aim of this study was to establish an accurate mouse formula using fetal biometric parameters under ultrasound imaging. Using a high-frequency ultrasound system with a 40 MHz transducer, we measured 293 fetuses of biparietal diameter and mean abdominal diameter from day 12.5 postcoitus (p.c.) until day 18.5 p.c every day. Thirteen algorithms for humans based on head and/or abdominal measurements were assessed. We established an accurate formula based on measurement of the abdomen in Jcl:ICR mice to investigate gestational complications, such as intrauterine growth restriction.
Faecal and caecal microbiota profiles of mice do not cluster in the same way
Authors: Pang Wanyong , Vogensen Finn Kvist , Nielsen Dennis Sandris , Hansen Axel Kornerup
Published: June 2012

Polymerase chain reaction (PCR)-based denaturation gradient gel electrophoresis (DGGE) is currently being used for characterizing the composition of the gut microbiota (GM) of mice in order to better control the study variation arising from the GM. At present, faeces are commonly sampled from live animals, while caecum is most commonly sampled from terminated animals. However, there is no knowledge whether the composition at the one site is representative for the other. In this study C57BL/6 mice were observed from the age of four weeks until the age of 10 weeks. Faeces were sampled weekly. Caecum was sampled surgically under anaesthesia and with subsequent ampicillin treatment at the age of six weeks and again after euthanasia at the age of 10 weeks. Faecal and caecal microbiota profiles were determined using DGGE and subjected to subsequent cluster analysis. The mice subjected to surgical caecal sampling clustered separately for two weeks after termination of antibiotics after which they again clustered with the non-surgically sampled mice. Faecal and caecal profiles clustered separately at the age of six weeks, but not at the age of 10 weeks. There were no correlations between faecal or caecal profiles at six or 10 weeks of age, respectively. It is concluded that faecal and caecal microbiota profiles are not representative of each other in mice. Therefore, it is recommendable in studies to sample from several sites specifically decided in relation to the specific model of a study.
Development and refinement of a technique using a medical radiation therapy facility to irradiate immunodeficient mice bearing xenografted human tumours
Authors: Baro Marta , de Llobet Lara I , Modolell Ignasi , Guedea Ferran , Visa Joana , Balart Josep
Published: June 2012

The need for using immunodeficient mice for xenoimplantation of tumours is increasing in translational research in radiation oncology. However, adverse effects of radiation and infectious diseases may ruin the experimental work, in particular when appropriate facilities are not available. In this report, we describe a procedure to deliver fractionated radiotherapy to xenoimplanted tumours in immunodeficient mice using a medical linear accelerator, a method that was devised as an alternative to the lack of facilities devoted to radiation research. The mice were irradiated under anaesthesia and aseptic conditions. Thirty Gray in 10 days using a 6 MV photon beam were delivered only to the right thigh of the mice where tumours were implanted. The mice were evaluated twice a week up to planned euthanasia. The follow-up of mice was completed without premature interruption due to toxicities or infectious diseases, an observation which demonstrates the feasibility of the method.
Estimation of an early meaningful time point of bone parameter changes in application to an osteoporotic rat model with in vivo microcomputed tomography measurements
Authors: Keiler Annekathrin Martina , Zierau Oliver , Vollmer Günter , Scharnweber Dieter , Bernhardt Ricardo
Published: June 2012

The commonly used preclinical animal model of postmenopausal osteoporosis is the mature ovariectomized rat, whereby cessation of ovarian oestrogen production consequently results in bone volume reduction. The study aim was to precisely define the time course of structural changes resulting from ovariectomy and thereby reduce the time animals have to be treated to judge the effects of osteoporosis treatment. For this purpose, we assessed architectural changes by microcomputed tomography ( μCT) during 10 weeks following ovariectomy or sham surgery at two-week intervals. Moreover, the trabecular microarchitecture of the lumbar vertebrae was assessed after necropsy. Besides this, serum biomarkers of bone turnover were determined. These data were in a new approach additionally correlated to femur mRNA expression profiles. We selected the osteoblast marker genes osteocalcin and type I collagen as well as the two osteoclast marker genes cathepsin k and tartrate-resistant acid phosphatase 5. The gene expression analysis suggested an activation of osteoblasts as well as octeoclasts. The significantly induced serum levels of osteocalcin and collagen degradation fragments also revealed this higher rate of bone turnover. Our results indicate that as soon as four weeks after ovariectomy the bone volume fraction exhibited a decline of 30% and 50% of the connectivity density. In addition, significant decreases of trabecular number and thickness as well as of the bone volume fraction were only observed in vertebrae of ovariectomized animals. Interestingly, changes of trabecular morphology were also found in the sham animals as a consequence of senescence.
Laryngeal perforation during a standard intubation procedure in a pig
Authors: Steinbacher R , von Ritgen S , Moens Y P S
Published: June 2012

Pigs are frequently anaesthetized in animal research settings. Due to the unique laryngeal anatomy, endotracheal intubation is demanding in pigs. Several complications associated with endotracheal intubation have been reported in pigs, but laryngeal perforation following difficult intubation has not been documented so far. The present case report describes laryngeal perforation in a three-month-old pig following difficult intubation.
An Optimization Approach to Airline Integrated Recovery
Authors: Petersen Jon D. , Sölveling Gustaf , Clarke John-Paul , Johnson Ellis L. , Shebalov Sergey
Published: June 2012

Although the airline industry has benefited from advancements made in computational and operational research methods, most implementations arise from the frictionless environment of the planning stage. Because 22% of all flights have been delayed and 3% have been cancelled in the United States since 2001, schedule perturbations are inevitable. The complexity of the operational environment is exacerbated by the need for obtaining a solution in as close to real-time as possible. Given some time horizon, the recovery process seeks to repair the flight schedule, aircraft rotations, crew schedule, and passenger itineraries in a tractable manner. Each component individually can be difficult to solve, so early research on irregular operations has studied these problems in isolation, leading to a sequential process by which the recovery process is conducted. Recent work has integrated a subset of these four components, usually abstracting from crew recovery. We present an optimization-based approach to solve the fully integrated airline recovery problem. After our solution methodology is presented, it is tested using data from an actual U.S. carrier with a dense hub-and-spoke network using a single-day horizon. It is shown that in several instances an integrated solution is delivered in a reasonable runtime. Moreover, we show the integrated approach can substantially improve the solution quality over the incumbent sequential approach. To the best of our knowledge, we are the first to present computational results on the fully integrated problem.
Mixed Integer Formulations for a Short Sea Fuel Oil Distribution Problem
Authors: Agra Agostinho , Christiansen Marielle , Delgado Alexandrino
Published: June 2012

We consider a short sea fuel oil distribution problem occurring in the archipelago at Cape Verde. Here, an oil company is responsible for the routing and scheduling of ships between the islands such that the demand for various fuel oil products is satisfied during the planning horizon. Inventory management considerations are taken into account at the demand side but not at the supply side. The ports have restricted opening hours each day, so multiple time windows are considered. In contrast to the ships in many other studies within ship routing and scheduling, ships here spend considerable time in the ports compared to at sea. Hence, the time in port is modeled in detail by incorporating both a variable (un)loading time and a setup time for loading different products in the same ports. A mathematical model of the problem is presented and it includes a combined continuous and discrete time horizon because of the multiple time windows and a daily varying consumption rate of the various products in the different ports. We discuss several strategies to improve the proposed model, such as tightening bounds, using extended formulations, and including valid inequalities. The computational study shows that the real problem can be solved to optimality within reasonable time by the use of improved formulations based on a combination of such strategies.
Long-Haul Vehicle Routing and Scheduling with Working Hour Rules
Authors: Rancourt Marie-Eve , Cordeau Jean-François , Laporte Gilbert
Published: June 2012

Long-haul carriers must comply with various safety rules which are rarely taken into account in models and algorithms for vehicle routing problems. In this paper, we consider the rules on truck driver safety during long-haul trips in the United States. The problem under study has two dominant features: a routing component that consists of determining the sequence of customers visited by each vehicle and a scheduling component that consists of planning the rest periods and the service time of each customer. We have developed different scheduling algorithms embedded within a tabu search heuristic. The overall solution methods were tested on modified Solomon instances, and the computational results confirm the benefits of using a sophisticated scheduling procedure when planning long-haul transportation.
A Reference Point Approach for the Resource Constrained Shortest Path Problems
Authors: Pugliese Luigi Di Puglia , Guerriero Francesca
Published: June 2012

The Resource Constrained Shortest Path Problem (ℛ 𝒞 𝒮 𝒫 𝒫) is a variant of the classical shortest path problem and is of great practical importance. The aim is to find the shortest path between a given pair of nodes under additional constraints representing upper bounds on the consumption of resources along the path. In the scientific literature, different approaches have been defined to solve the ℛ 𝒞 𝒮 𝒫 𝒫. In this work we propose an innovative interactive method to address the ℛ 𝒞 𝒮 𝒫 𝒫, based on a novel search strategy of the criteria space. The performance of the proposed approach is evaluated on the basis of an extensive computational study by considering benchmark instances. A comparison with the state-of-the-art approaches developed for the ℛ 𝒞 𝒮 𝒫 𝒫 is also carried out. The computational results have shown that the developed solution strategy is competitive with the most efficient strategies known thus far.
Bid Prices When Demand Is a Mix of Individual and Batch Bookings
Authors: Popescu Andreea , Barnes Earl , Johnson Ellis , Keskinocak Pinar
Published: June 2012

Industries such as aviation, hospitality, and package tours often face both individual and batch bookings, requiring one unit and multiple units of capacity, respectively. Using bid prices is a common practice in accepting or rejecting an incoming booking (or equivalently, deciding which price bucket to offer to the incoming bookings at a given time). Most of the literature and existing applications for making accept/reject decisions model the arrival stream as individual bookings. In this paper, we propose an effective approach to determine bid prices when there is a mixed demand pattern with individual and batch bookings. We propose decomposing the demand into “small” and “large” bookings, using dynamic programming for large bookings, and a fast, high-quality approximation for small bookings. We present an application of our approach in the air cargo industry, where cargo is often separated into two categories, namely, mail and packages (small cargo) and freight (large cargo). To obtain bid prices for small cargo, we approximate cargo booking requests with passenger arrival models and develop an efficient and effective algorithm to solve the probabilistic nonlinear formulation of the seat allocation problem from the passenger literature. To obtain bid prices for large cargo, we solve a dynamic program decomposed by flight leg, which is tractable due to the scattered arrivals and large sizes of the bookings. Our approach leads to a significant potential increase in revenues compared to the first-come, first-served (FCFS) approach and the solution from the deterministic formulation (DIP), two methods commonly used in practice.
New Lower Bounds and Exact Method for the m-PVRP
Authors: Ngueveu Sandra Ulrich , Prins Christian , Wolfler Calvo Roberto
Published: June 2012

This paper presents new lower bounding procedures and an exact method for the m-peripatetic vehicle routing problem (m-PVRP) based on polyhedral and column generation approaches. The branch-and-cut algorithms use three types of valid cuts on the edge-based formulation. The column-generation-based lower bounding procedure is applied on the dual set partitioning formulation and is composed of dual heuristics that estimate good dual variable values and therefore high lower bounds. Computational results on instances from the literature show that these new lower bounds reach on average 97.5% to 99% of the best known upper bounds and optimality is proven for a third of the instances.
Expected Future Value Decomposition Based Bid Price Generation for Large-Scale Network Revenue Management
Authors: Escudero L. F. , Monge J. F. , Morales D. Romero , Wang J.
Published: June 2012

This paper studies a multistage stochastic programming (SP) model for large-scale network revenue management. We solve the model by means of the so-called expected future value (EFV) decomposition via scenario analysis, estimating the impact of the decisions made at a given stage on the objective function value related to the future stages. The EFV curves are used to define bid prices on bundles of resources directly, as opposed to the traditional additive approach. We compare our revenues to those obtained by additive bid prices, such as the bid prices derived from the deterministic equivalent model (DEM) of the compact representation of the SP model. Our computational experience shows that the revenues obtained by our approach are better for middle-range values of the load factor of demand, whereas the differences among all the approaches we have tested are insignificant for extreme values. Moreover, our approach requires significantly less computation time than does the optimization of DEM by plain use of optimization engines. Problem instances with 72 pairs of bundle-fare classes have been solved in less than one minute, with 800 pairs in less than five minutes, and with 4,000 pairs in less than one hour. The time taken by DEM was, in general, of one order of magnitude higher. Finally, for the three largest problem instances, and after two hours, the expected revenue returned by DEM was below that obtained by EFV by 13.47%, 17.14%, and 38.94%, respectively.
Approximation Algorithms for Capacitated Location Routing
Authors: Harks Tobias , König Felix G , Matuschke Jannik
Published: June 2012

An approximation algorithm for an optimization problem runs in polynomial time for all instances and is guaranteed to deliver solutions with bounded optimality gap. We derive such algorithms for different variants of capacitated location routing, an important generalization of vehicle routing where the cost of opening the depots from which vehicles operate is taken into account. Our results originate from combining algorithms and lower bounds for different relaxations of the original problem; along with location routing we also obtain approximation algorithms for multidepot capacitated vehicle routing by this framework. Moreover, we extend our results to further generalizations of both problems, including a prize-collecting variant, a group version, and a variant where cross-docking is allowed. We finally present a computational study of our approximation algorithm for capacitated location routing on benchmark instances and large-scale randomly generated instances. Our study reveals that the quality of the computed solutions is much closer to optimality than the provable approximation factor.
Service-Oriented Line Planning and Timetabling for Passenger Trains
Authors: Kaspi Mor , Raviv Tal
Published: June 2012

An integrated line planning and timetabling model is formulated with the objective of minimizing both user inconvenience and operational costs. User inconvenience is modeled as the total time passengers spend in a railway system, including waiting at origin and transfer stations. The model is solved using a cross-entropy metaheuristic. The line plan and timetable of Israel Railways is used as a benchmark. Using the same amount of resources, the average journey time of passengers is reduced by 20%.
Beyond Diagnostic Accuracy: The Clinical Utility of Diagnostic Tests
Authors: Bossuyt Patrick MM , Reitsma Johannes B , Linnet Kristian , Moons Karel GM
Published: June 2012

Like any other medical technology or intervention, diagnostic tests should be thoroughly evaluated before their introduction into daily practice. Increasingly, decision makers, physicians, and other users of diagnostic tests request more than simple measures of a test's analytical or technical performance and diagnostic accuracy; they would also like to see testing lead to health benefits. In this last article of our series, we introduce the notion of clinical utility, which expresses—preferably in a quantitative form—to what extent diagnostic testing improves health outcomes relative to the current best alternative, which could be some other form of testing or no testing at all. In most cases, diagnostic tests improve patient outcomes by providing information that can be used to identify patients who will benefit from helpful downstream management actions, such as effective treatment in individuals with positive test results and no treatment for those with negative results. We describe how comparative randomized clinical trials can be used to estimate clinical utility. We contrast the definition of clinical utility with that of the personal utility of tests and markers. We show how diagnostic accuracy can be linked to clinical utility through an appropriate definition of the target condition in diagnostic-accuracy studies.
A Review on Metaanalysis of Biomarkers: Promises and Pitfalls
Authors: Lewington Sarah , Bragg Fiona , Clarke Robert
Published: June 2012

BACKGROUND

The last 30 years have seen an exponential increase in metaanalyses. By combining multiple studies, metaanalysis can provide an overview of the totality of evidence on a particular question and the statistical power needed to reduce random error and produce precise estimates of even modest effect sizes. This capability is of particular value when many small studies address similar questions [such as in the investigation of novel cardiovascular disease (CVD) biomarkers]. To provide reliable evidence, however, metaanalyses must be undertaken robustly.

CONTENT

In this review, we describe the major issues to consider when designing and conducting metaanalyses, including the design of constituent studies, selection criteria, assessment of exposures and disease outcomes, and control of bias and confounding. Some of the potential challenges and pitfalls associated with metaanalysis are examined, and their consequences are considered. We use 2 examples of novel biomarkers for CVD—homocysteine and triglycerides—to illustrate how metaanalyses of observational studies have contributed to, and on occasion hindered, our understanding; and how subsequent work has built upon these findings.

Metaanalyses of observational studies, particularly metaanalyses of individual-participant data, have the power to provide robust evidence to support our understanding of the role of novel biomarkers for disease. The characteristic limitations and challenges of these studies, including their inability to detect causal associations, must be considered, however, and additional evidence from randomized controlled trials and genetic studies is frequently required to elucidate fully the role of novel biomarkers in predicting cardiovascular risk.
Biases Introduced by Choosing Controls to Match Risk Factors of Cases in Biomarker Research
Authors: Sullivan Pepe Margaret , Fan Jing , Seymour Christopher W , Li Christopher , Huang Ying , Feng Ziding
Published: June 2012

BACKGROUND

Selecting controls that match cases on risk factors for the outcome is a pervasive practice in biomarker research studies. Such matching, however, biases estimates of biomarker prediction performance. The magnitudes of these biases are unknown.

METHODS

We examined the prediction performance of biomarkers and improvements in prediction gained by adding biomarkers to risk factor information. Data simulated from bivariate normal statistical models and data from a study to identify critically ill patients were used. We compared true performance with that estimated from case control studies that do or do not use matching. ROC curves were used to quantify performance. We propose a new statistical method to estimate prediction performance from matched studies for which data on the matching factors are available for subjects in the population.

RESULTS

Performance estimated with standard analyses can be grossly biased by matching, especially when biomarkers are highly correlated with matching risk factors. In our studies, the performance of the biomarker alone was underestimated whereas the improvement in performance gained by adding the marker to risk factors was overestimated by 2–10-fold. We found examples for which the relative ranking of 2 biomarkers for prediction was inappropriately reversed by use of a matched design. The new approach to estimation corrected for bias in matched studies.

CONCLUSIONS

To properly gauge prediction performance in the population or the improvement gained by adding a biomarker to known risk factors, matched case control studies must be supplemented with risk factor information from the population and must be analyzed with nonstandard statistical methods.
In Vitro 5-LOX Inhibitory and Antioxidant Activities of Extracts and Compounds from the Aerial Parts of Lopholaena coriifolia (Sond.) E. Phillips & C.A. Sm.
Authors: Wijaya Sumi , Jin Khoo Teng , Nee Ting Kang , Wiart Christophe
Published: June 2012

The aim of this study was to investigate the antioxidant and anti-inflammatory potentials of crude extracts of Lopholaena coriifolia (Sond.) E. Phillips & C.A. Sm. and its isolated compounds. Separation and structure elucidation of Lopholaena coriifolia (Sond.) E. Phillips & C.A. Sm. were conducted using chromatographic and spectroscopic method. The antioxidant activities of the extracts in this study were determined by the ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene bleaching assays meanwhile the anti-inflammatory activity was evaluated using the 5-lipoxygenase assay. Seven known compounds quercetin 3-O-glucoside (1), naringenin 7-O-glucoside (2), seneciphylline-O-glucoside (3), chrysoeriol (4), retrorsine (5), adonifiline (6) and 5,4′-di-O-methyl alpinumisoflavone (7) were isolated from ethanol extract of Lopholaena coriifolia (Sond.) E. Phillips & C.A. Sm. The ethanol and water extracts of Lopholaena coriifolia (Sond.) E. Phillips & C.A. Sm. elicited potent antioxidant and anti-inflammatory properties. Amongst the isolated compounds quercetin 3-O-glucoside gave strong antioxidant activity and adonifiline strongly inhibited 5-lipoxygenase activity.
Corrective Measures in Islanding Scheme at Bhusawal Thermal Power Station - Case Study
Authors: Ballal Makarand Sudhakar , Suryawanshi Hiralal M.
Published: June 2012

System islanding is often considered as the final stage of power system defense plans. The goal is to preserve stable areas of the faulted power systems. The islanding scheme plays an important role in the power system restoration phase as it can make the power system restoration less complex and reduce the overall restoration time. The basis for islanding is not standard but rather depends upon the nature of the utility. Even though the formation of islands is dominated by geographical proximity of the synchronous generators to maintain generation-load balance, there are some factors which can assist in designing a better islanding scheme. These factors are the type and location of the fault and the dynamic performance of every island on the system against the fault. This paper present the application of islanding scheme and its performance operation for the scheme commissioned at 132 kV Deepnagar Bhusawal Thermal Power Station (BTPS). The methods and constraints of islanding scheme are discussed in details. Case studies regarding performance of islanding scheme are also described.
Adsorption of Cadmium on Gel Combustion Derived Nano ZnO
Authors: V Venkatesham , G.M Madhu , S V Satyanarayana , H S Preetham
Published: June 2012

Large amount of heavy metal ions disposed in wastewater by various industries causes environmental pollution and toxicity in waste water. Many naturally available materials were used as adsorbents for the removal of heavy metal ions, but they are not effective because of low surface area. Novel nano materials are used as adsorbents in the removal of metal ions to treat potable water. In the present work nano sized large surface area (80.425 m2/g) Zinc Oxide (ZnO) was synthesized by gel combustion method and used as an adsorbent for the removal of cadmium (II) (Cd2+) from aqueous solution. The nano ZnO and Cd adsorbed ZnO were characterized by XRD, the additional Cd peaks in XRD pattern confirms the Cd adsorption. SEM analysis confirmed the adsorption of Cd2+ by change in the morphology of adsorbent. Percentage purity of the element and the presence of the Cd were characterized by EDAX. Adsorption of Cd2+ on ZnO was confirmed by varying parameters like initial concentration, pH and adsorbent dosage. Cadmium concentration in the solution was analyzed using Atomic Absorption Spectrometer (AAS). Increase in the initial concentration of Cd solution, decreases the percentage of adsorption, where as increase in the adsorbent dosage and pH of the solution increases the adsorption of Cd2+ on ZnO. Synthesized nano ZnO shows maximum of 95% Cd adsorption at lower initial concentration. Experimental data fits Langmuir and Freundlich adsorption isotherm models.
Clinically insignificant improvement of prostate cancer prediction by addition of sex steroid hormones and SHBG serum levels to serum PSA, fPSA%, and age in a screening setting
Authors: Heidegger Isabel , Popovscaia Marina , Ramoner Reinhold , Schäfer Georg , Stenzel Birgit , Bektic Jasmin , Horninger Wolfgang , Klocker Helmut
Published: June 2012

Various findings implicate sex hormones in prostate growth and development and also in prostate carcinogenesis. We investigated if addition of sex steroid hormone and sex hormone binding globulin (SHBG) serum levels to standard risk assessment parameters [prostate-specific antigen (PSA), free PSA percentage (fPSA%), and age] improves prostate cancer prediction in a PSA screening setting. Steroid hormones testosterone (T), free testosterone (fT), and estradiol (E2), and binding protein SHBG levels were measured in 762 men undergoing prostate biopsy due to suspect PSA serum levels. Prostate cancer was diagnosed in 286 (37.5%) of these men. Our data confirmed that PSA (mean BE=5.09; mean CA=6.05; p=1.24×10–5), fPSA% (mean BE=22.08; mean CA=18.67; p=1.97×10–7), and age (mean BE=60.64; mean CA=64.5; p=7.05×10–10) differentiate men with cancer (CA) and men with benign disease (BE), such as benign prostate hyperplasia. In addition, SHBG (mean BE=50.3; mean CA=54.9; p=0.008) also differed statistically significantly between these two groups. All hormones except E2 and tumor markers correlated significantly with age (T: ρ=–0.09; fT: ρ=–0.27; SHBG: ρ=0.21; PSA: ρ=0.32; and fPSA%: ρ=0.22). Furthermore, we found that PSA correlates with E2 (ρ=0.08), and fPSA% with SHBG (ρ=0.1) and fT (ρ=–0.09). Addition of hormones and SHBG to a baseline marker model including PSA, fPSA%, and age improved cancer prediction in three multivariate classification methods; however, the improvement was minimal. The best improvement by 0.8% was obtained in the logistic regression model with the addition of T and SHBG or of E2 and SHBG, or in the support vector machine model with the addition of SHBG and all steroid hormones to the combination of standard markers PSA, fPSA%, and age; however, this additional gain of accuracy is too small to justify the additional efforts and costs.
Finite groups with NR-subgroups or their generalizations
Authors: Malinowska Izabela Agata
Published: June 2012

Yakov Berkovich investigated the following concept: a subgroup
Some exceptional Beauville structures
Authors: Fairbairn Ben
Published: June 2012

We show that every quasisimple sporadic group apart from the Mathieu groups
Numerical method for solving an inverse electrocardiography problem for a quasi stationary case
Authors: Denisov Alexander M. , Zakharov Eugene V. , Kalinin Alexander V. , Kalinin Vitaliy V.
Published: June 2012

An inverse electrocardiography problem for a different time moment is studied. The realistic 3D geometry of human torso and chest medium with piecewise constant electrical conductivity are considered. A numerical method for solving the inverse electrocardiography problem at a given time moment is suggested. Results of comparison of numerical solutions to the inverse electrocardiography problems for a clinical data on torso surface and a clinical measurement inside of heart are given.
Influência da torra sobre a aceitação da bebida café
Authors: Monteiro Marlene Azevedo Magalhães , Minim Valéria Paula Rodrigues , Silva Aline Fonseca da , Chaves José Benício Paes
Published: June 2012

O café é um dos poucos produtos agrícolas valorizado com base em parâmetros qualitativos, em que quanto melhor for a qualidade maior será o preço obtido. Essa qualidade, contudo, é dependente de diversos fatores que se relacionam em todas as etapas da sua produção, desde a escolha da variedade ou de cultivar a ser plantada até o preparo da bebida. A torração é uma etapa muito importante para a qualidade do café, estando diretamente relacionada à aceitação da bebida. O presente trabalho teve por objetivo avaliar a aceitação ou preferência das bebidas tipo mole, dura e rio de café submetidas a três diferentes tipos de torra (clara, expresso e escura). Foi realizado um teste de aceitação com 65 consumidores de café, utilizando-se uma escala hedônica de nove pontos, sendo avaliados separadamente a cor, o aroma, o sabor e a impressão global. Os resultados foram avaliados por meio do Mapa de Preferência Interno (MDPREF). As amostras de torra escura, independentemente do tipo de bebida, foram de maior preferência dos consumidores em relação aos atributos cor, aroma, sabor e impressão global. As de torra clara, rio/expresso e dura/expresso, de acordo com os consumidores, tiveram menor preferência quanto à cor. Para os atributos aroma, sabor e impressão global as amostras de torra clara e rio/expresso foram menos aceitas.
Estudo de mercado de iogurte da cidade de Belo Horizonte/MG
Authors: Ribeiro Milene Moreira , Minim Valéria Paula Rodrigues , Minim Luis Antônio , Arruda Aline Cristina , Ceresino Elaine Berger , Carneiro Helena Cristina Ferrer , Cipriano Paula de Aguiar
Published: June 2012

O estudo do perfil dos consumidores e dos fatores envolvidos no processo de compra do iogurte é uma ferramenta importante na identificação dos diferentes segmentos desse mercado e de suas potencialidades. Assim, neste trabalho entrevistaram-se 387 consumidores de iogurte, residentes em Belo Horizonte - MG, que responderam os questionários estruturados. Os resultados foram analisados de forma descritiva, e para verificar a correlação entre características sociodemográficas com o perfil de consumo aplicou-se a análise de correlação de Pearson. Os resultados indicaram que o iogurte sabor morango apresenta maior aceitação pelos consumidores, que a categoria light/diet possui grande parte do seu público consumidor (54%). Segundo a pesquisa, 39,9% dos respondentes que não consomem iogurte light/diet disseram não consumi-lo por não gostar desse produto. Isto revela a importância de pesquisas para desenvolvimento de iogurte light/diet visando à melhoria da qualidade sensorial. O fato de não ver necessidade de consumir o produto foi apontado como um dos principais motivos por não consumir iogurte da categoria light/diet. A qualidade, a marca e o preço apresentaram grande importância na conquista de mercado, sendo os três principais atributos observados no momento da compra de iogurte na cidade estudada. Analisando a correlação entre consumo e fator sociodemográfico, observou-se que a renda e a idade influenciam tanto na frequência de consumo de iogurte quanto no consumo do produto na versão light/diet.
Efeitos de diferentes estratégias de controle no ambiente de armazenamento de grãos em regiões tropicais e subtropicais
Authors: Lopes Daniela de Carvalho , Martins José Helvecio , Monteiro Paulo Marcos de Barros , Lacerda Filho Adílio Flauzino
Published: June 2012

Neste trabalho, estratégias de controle para aeração de grãos baseadas em temporizador, termostato e termostato combinado com umidostatos foram comparadas ao controlador AERO. Apesar de simples, as três primeiras estratégias são amplamente empregadas, resultando em controles confiáveis e em grande aceitação por parte dos produtores. O AERO foi desenvolvido na Universidade Federal de Viçosa com o objetivo de difundir e facilitar a utilização de estratégias mais sofisticadas pelos produtores. Este controlador atua com base em dados medidos em tempo real e na simulação do processo de aeração. Os resultados mostraram que os tempos requeridos para aeração, além dos níveis de deterioração, das temperaturas e dos teores finais de água dos grãos foram parecidos para as quatro estratégias analisadas quando se considerou as melhores configurações para as três estratégias simples. Entretanto, o AERO apresentou um controle mais eficiente, resfriando a massa de grãos mais rapidamente e minimizando as oscilações de temperatura e de teor de água dos grãos durante o processo de aeração. Outra vantagem do AERO é sua capacidade de ajustar automaticamente as suas condições de controle de acordo com as condições climáticas da região onde o sistema está implantado.
Tensão térmica e taxa de reação em um reator para gaseificação de biomassa do tipo concorrente
Authors: Martin Samuel , Silva Jadir Nogueira da , Oliveira Filho Delly , Donzeles Sérgio M. Lopes , Zanatta Fábio Luis , Santos Reginaldo Rodrigues dos
Published: June 2012

A conversão da energia química da biomassa em outras formas de energia pode ser processada de diversas maneiras. Dentre essas, encontra-se a gaseificação, que utiliza reatores para conversão da biomassa em gás combustível. Para o dimensionamento de um gaseificador e seus constituintes, vários fatores devem ser levados em consideração, desde as características do combustível até as reais necessidades de energia térmica liberada. Especificamente no dimensionamento da grelha, alguns índices servem de referência, como a tensão térmica e a taxa de reação. Este trabalho teve como objetivos determinar a taxa de reação e a tensão térmica de uma grelha plana utilizada em um gaseificador bem como comparar os valores obtidos com aqueles recomendados para o dimensionamento de grelhas em fornalhas. Foi utilizado um gaseificador de biomassa de fluxo concorrente de pequena escala, ao qual foi acoplada uma câmara para combustão do gás produzido. O combustível utilizado foi toretes de eucalipto, em pedaços com diâmetro de 4 a 8 cm e comprimento de 10 a 20 cm. Conclui-se que os índices de taxa de reação e tensão térmica encontrados podem ser utilizados como parâmetros para o dimensionamento de grelhas de gaseificadores de leito fixo.
Observações anatômicas em plantas de Coffea arabica L. obtidas por enraizamento de estacas
Authors: Jesus Adriana Madeira Santos , Carvalho Samuel Pereira de , Castro Evaristo Mauro de , Gomes Carlos Nick
Published: June 2012

Uma forma para se obter diminuição significativa de tempo e recursos despendidos nos programas de melhoramento de Coffea arabica L. é a clonagem de híbridos F1 por meio de estacas caulinares. Alguns estudos, em diferentes instituições, foram realizados buscando-se definir um método eficiente para esse tipo de clonagem. Com o objetivo de verificar-se a presença de barreiras anatômicas ao enraizamento de estacas caulinares do cafeeiro e a origem das raízes adventícias, bem como compara-las às raízes provenientes de plantas obtidas por semeadura, foram realizadas análises anatômicas no Departamento de Biologia da Universidade Federal de Lavras (UFLA), Lavras, MG. Utilizaram-se estacas caulinares de cafeeiro dos cultivares Acaiá e Rubi e mudas obtidas por semeadura direta e por estaquia. Os cortes realizados nas estacas caulinares mostraram não existirem barreiras anatômicas ao enraizamento adventício. Nas estacas enraizadas, a origem do primórdio radicular foi próxima aos tecidos vasculares. Cortes histológicos nas raízes formadas nas estacas e nas raízes de mudas obtidas por semeadura confirmaram que elas apresentam as mesmas estruturas primárias.
Primeiro registro do gênero Toxorhynchites Theobald (Diptera, Culicidae) em Mata Atlântica, Viçosa, Minas Gerais
Authors: Albeny Daniel Simões , Rosa Cassiano Sousa , Ataíde Lívia Maria Silva , Vilela Evaldo Ferreira
Published: June 2012

Durante os meses de março e abril de 2007 foi verificada a presença do gênero Toxorhynchites (Diptera, Culicidae) em fragmentos de Mata Atlântica no município de Viçosa, Minas Gerais, Brasil. No experimento foram utilizadas 500 armadilhas de oviposição. Registrando-se, pela primeira vez na região de Viçosa o gênero Toxorhynchites, sendo as espécies T. pusillus (Costa Lima, 193 1) e T. theobaldi (Dyar & Knab, 1906) encontradas pela primeira vez no Estado de Minas Gerais. As espécies relatadas como primeiro registro e sua distribuição são citadas e discutidas.
Variability in leaf rust susceptibility among peach cultivars
Authors: Citadin Idemir , Mazaro Sérgio Miguel , Danner Moeses Andrigo , Raseira Maria do Carmo Bassols , Malagi Gustavo
Published: June 2012

The aim of this work was to estimate the susceptibility of thirty-six peach cultivars to leaf rust caused by Tranzschelia discolor f. sp. persica. The incidence and severity of the disease as well as defoliation in peach trees of an experimental orchard of Parana Federal University of Technology, Campus Dois Vizinhos were evaluated on the growing seasons 2004/2005 and 2005/2006. Immunity to this disease was not observed in the studied cultivars. There was difference in leaf rust intensity depending on the growing season conditions. Cultivars 'Pilcha', 'Sinuelo', 'Chirua', 'Sulina', 'Eldorado' and 'Pampeano' showed tolerance to leaf rust, whereas cultivars 'Vila Nova', 'Fla 1372', 'Coral 2', 'Chimarrita', 'Della Nona', 'BR-1 ' and 'Guaiaca' showed high susceptibility.
Comunidade de parasitóides associada à cultura do café em Piatã, Chapada Diamantina, BA
Authors: Palma-Santos Magno Clery da , Pérez-Maluf Raquel
Published: June 2012

Os himenópteros parasitoides são inimigos naturais de insetos-praga e têm demonstrado eficiência em estratégias de controle, contribuindo para a manutenção do equilíbrio ecológico de agroecossistemas. Esta pesquisa buscou identificar a diversidade de parasitoides associada a culturas de café em Piatã, BA. As coletas foram realizadas com armadilhas Malaise, que permaneceram no campo por sete dias em coletas mensais, de setembro de 2006 a agosto de 2007. Foram coletados 14.669 himenópteros, distribuídos em nove superfamílias, sendo elas Ceraphronoidea, Chalcidoidea, Chrysidoidea, Cynipoidea, Evanioidea, Ichneumonoidea, Mymarommatoidea, Platygastroidea e Proctotrupoidea, e 29 famílias. Coletaram-se 22 famílias constantes e 11 dominantes, destacando-se Ichneumonidae, Braconidae e Scelionidae como mais frequentes, totalizando 50,33% dos indivíduos coletados. As famílias Braconidae, Eulophidae e Bethylidae, indicadas como promissoras em programas de controle biológico no café, foram coletadas ao longo de todo o ciclo fenológico do café.
Anestesia por infusão contínua de propofol associado ao remifentanil em gatos pré-tratados com acepromazina
Authors: Mata Lukiya Birungi Silva Campos , Pompermayer Luiz Gonzaga , Favarato Evandro Silva , Costa Junior Jair Duarte da , Neves Cinthya Dessaune , Pereira Taciana , Argolo Neto Napoleão Martins
Published: June 2012

O presente trabalho avaliou a associação anestésica do propofol, um anestésico geral de ação ultracurta e metabolismo rápido, ao remifentanil, opioide de grande poder analgésico, que potencializa os anestésicos gerais. O objetivo principal foi desenvolver um protocolo anestésico de uso intravenoso, por infusão contínua, que proporcione conforto ao paciente, segurança, com grande relaxamento muscular e analgesia em gatos submetidos a cirurgias eletivas como a ovariosalpingoisterectomia e orquiectomia. Foram utilizados 30 gatos, aleatoriamente distribuídos em 3 grupos de 10 animais. Em todos eles realizou-se a tranquilização com acepromazina (0,1 mg/kg, IM) e indução anestésica com propofol (6 mg/kg, IV). No grupo 1, a anestesia foi mantida por infusão contínua de propofol (0,6 mg/kg/min), no grupo 2, com propofol (0,4 mg/kg/min) e remifentanil (0,1 µg/kg/min), e no grupo 3, com propofol (0,4 mg/kg/min) e remifentanil (0,2 µg/kg/min). As variáveis mensuradas foram: temperatura corporal, frequência cardíaca, frequência respiratória, saturação da oxiemoglobina, pressão arterial sistólica, hemogasometria arterial, analgesia e miorrelaxamento. Após análise dos resultados, pode-se concluir que o remifentanil promoveu incremento da analgesia, permitindo redução de 33% na velocidade de infusão do propofol, entretanto a infusão de 0,2 µg/kg/min de remifentanil determinou maior depressão respiratória quando comparada à infusão de 0,1 µg/kg/min.
Estimativas de ganho genético por diferentes critérios de seleção em genótipos de alfafa
Authors: Vasconcelos Edmar Soares de , Ferreira Reinaldo de Paula , Cruz Cosme Damião , Moreira Adônis , Rassini Joaquim Bartolomeu , Freitas Alfredo Ribeiro de
Published: June 2012

Este estudo foi desenvolvido objetivando comparar diferentes critérios de seleção, indicar o método de seleção que propicia maiores estimativas de ganho genético e identificar genótipos superiores de alfafa quanto a características produtivas, morfológicas e bromatológicas. Foram avaliadas a produção de matéria seca, altura de planta, tolerância a doenças, aceitação fenotípica pelos animais, proteína bruta, digestibilidade in vitro da matéria seca, fibra em detergente neutro e relação caule/folha de 92 acessos provenientes do INTA-Argentina, tendo como testemunha o Crioula. Os Índices de Mulamba & Mock, distância do genótipo ao ideótipo e Elston foram os mais adequados a esse tipo de estudo. Os genótipos Sequel, CUF 101, Siriver 2, Florida 77, Diamond, Sequel 2, LE N 2, Medina, Kern, Rio Grande, DK 166, DK 181, Perla SP INTA, WL 516, Rocio, LE Semit 711 e LE N 3 foram os indicados à seleção pelos maiores índices de Mulamba e Mock, distância do genótipo ao ideótipo e índice de Elston.
Comportamentos de amamentação e mamada em bubalinos, suas relações com período de lactação, idade e sexo dos bezerros
Authors: Madella-Oliveira Aparecida de Fátima , Bastos Rosemary , Quirino Célia Raquel
Published: June 2012

Objetivou-se neste trabalho investigar a frequência e a duração dos tipos de amamentações durante o período de lactação em fêmeas bubalinas e os tipos de mamadas em relação à idade e ao sexo dos bezerros. Trinta e cinco fêmeas e seus bezerros foram observados durante três dias consecutivos a cada mês, ao longo de nove meses. A amamentação foi caracterizada como: amamentação filial isolada (AFI), amamentação filial coletiva (AFC) e amamentação não-filial (ANF). As mamadas executadas pelos bezerros foram caracterizadas como: mamada filial isolada (MFI), mamada filial coletiva na própria mãe (MFC 1), mamada filial coletiva em outra fêmea (MCF2) e mamada não-filial (MNF). Os dados foram analisados pela análise de variância, e as médias foram comparadas pelo teste Tukey, considerando P < 0,05. A AFI apresentou frequência e duração maiores do que os outros tipos de amamentações (P < 0,05), sendo predominante em quase todo o período de lactação. A frequência da MFI foi alta, principalmente no primeiro mês. A duração foi maior quando comparada aos outros tipos de mamadas até o quinto mês (P < 0,05). Em relação ao sexo dos bezerros não foram encontradas diferenças significativas (P > 0,05) para as médias da frequência e a duração dos tipos de mamadas. Os resultados mostram que as fêmeas bubalinas têm maior aptidão inata para a AFI em relação aos outros tipos de amamentações, predominando durante quase todo o período de lactação. Os bezerros bubalinos são mais dependentes da MFI durante os primeiros cinco meses de idade, e o sexo dos bezerros não influenciou nos tipos de mamadas.
Qualidade de cenouras em diferentes densidades populacionais
Authors: Alves Samara Sibelle Vieira , Negreiros Maria Zuleide de , Aroucha Edna Maria Mendes , Lopes Welder de Araújo Rangel , Teófilo Taliane Maria da Silva , Freitas Francisco Cláudio Lopes de , Nunes Glauber Henrique de Sousa
Published: June 2012

Foi objetivo avaliar os efeitos de diferentes espaçamentos de plantio sobre a qualidade de raízes de três cultivares de cenoura nas condições de Mossoró, Rio Grande do Norte. O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial 6 x 3, com três repetições, sendo o primeiro fator constituído pelos espaçamentos: 20 x 4, 20 x 6, 20 x 8, 15 x 4, 15 x 6 e 15 x 8 cm e o segundo, pelos cultivares: Brasília, Alvorada e Esplanada. As características avaliadas nas raízes de cenoura foram: comprimento da raiz, diâmetro da raiz, comprimento do xilema, diâmetro do xilema, sólidos solúveis (SS), açúcares totais, acidez total (AT), vitamina C, relação SS/AT e pH. Não houve interação significativa entre cultivares e espaçamentos de plantio em qualquer das características avaliadas. Os espaçamentos influenciaram o comprimento e diâmetro da raiz e o comprimento e diâmetro do xilema. O cultivar Alvorada sobressaiuse nos sólidos solúveis, açúcares solúveis totais e relação SS/AT.