bluuebunny/crossref_metadata_2025 huggingface dataset:
Probing the Universe with cosmic rays using high performance computing
Authors: Potgieter Marius
Published: April 2009

I report on the research activities of the South African Centre for High Performance Computing carried out at the Unit for Space Physics at North-West University, Potchefstroom, during 2007/8. Background is given on the aims of the centre and the first three flagship projects that were selected in 2006 for computational-intensive tasks. The project in Computational Space Physics and Astrophysics, called 'Cosmic rays and us: From birth to death', is described in detail, and a summary given of research highlights so far.
Description of the postcranial anatomy of Aulacephalodon baini and its possible relationship with 'Aulacephalodon peavoti'
Authors: Govender Romala
Published: April 2009

A recent analysis of the postcranial anatomy of Triassic dicynodonts renewed interest in the anatomy of Aulacephalodon. This study focused initially on Aulacephalodon baini as it represents medium to large Permian dicynodonts but also took into account 'Aulacephalodon peavoti'. The postcranial skeletons of A. baini and 'A. peavoti' show several significant differences. The scapula blade of A. baini is more curved than and not as upright as in 'A. peavoti'. A. baini has a rectangular delto-pectoral crest and has a better developed olecranon. In the pelvic girdle the anterior process is higher than the posterior process of the ilium in A. baini and the acetabulum is directed more ventrally. The femoral head is separated from the greater trochanter in A. baini. A comparison also shows that both A. baini and 'A. peavoti' are different from Rhachiocephalus in that the latter has a widely expanded scapula blade and the proximal end of the humerus is wider than the distal. The glenoid is elliptical with a convex surface. Although it could not be conclusively decided what the taxonomic position of 'A. peavoti' is, this study provides information about the postcranial skeleton which could aid its detailed analysis. This study will also assist in clarifying the relationships as well as providing insight into the palaeobiology of these extinct tetrapods.
Vegetation associated with the occurrence of the Brenton blue butterfly
Authors: Edge D.A. , Cilliers S.S. , Terblanche R.F.
Published: April 2009

The Brenton blue butterfly, Orachrysops niobe (Trimen), is critically endangered and known only from one site near Knysna in the Western Cape province of South Africa, now proclaimed as the Brenton Blue Butterfly Reserve (BBBR). We have explored associations between vegetation types and the presence of O. niobe's only host plant, Indigofera erecta (Thunb.), using Braun-Blanquet vegetation classification and ordination techniques as part of a broader research project at the BBBR. Positive correlations are demonstrated between the occurrence of I. erecta and certain thicket vegetation types dominated by Pterocelastrus tricuspidatus (candlewood trees). Ordinations using soil analysis and slope data have not detected significant environmental gradients influencing vegetation types. The high degree of vegetation heterogeneity at the BBBR appears to be driven in part by various disturbance histories. Historical ecological events at the site such as fire and megaherbivore impacts, and their role in sustaining the ideal habitat for I. erecta and O. niobe, are discussed. Management techniques for the BBBR such as controlled fires or the cutting of paths through the vegetation are evaluated and an optimum future management strategy is recommended. This is the most comprehensive vegetation study ever carried out at the habitat of an endangered butterfly in South Africa, and breaks new ground by using vegetation analysis to develop a well-informed management plan for conservation of this species. It has significance for the management of small sites where many such endangered butterflies occur.
Human response and adaptation to drought in the arid zone: lessons from southern Africa
Authors: O'Farrell P.J. , Anderson P.M.L. , Milton S.J. , Dean W.R.J.
Published: April 2009

Human adaptation and response to drought is primarily through evasion or endurance. A review of historical agricultural practices in southern Africa demonstrates evidence of drought evasion response strategies in well-established transhumance routes, where herders move livestock on a seasonal basis in order to exploit resources subject to different climatic regimes. European settlers to the arid regions of South Africa quickly recognised the necessity of these evasion options to survive drought, and adopted the transhumance practices of indigenous farmers. Areas of geographically diverse resource bases became hotly contested by settlers and indigenous farmers. The success of evasion systems are shown to hinge on good social and institutional support structures. When movement is not an option, drought endurance is pursued by attempting to limit the damage to the natural resource base. This is through a number of means such as forage conservation, varying livestock types and numbers, water and soil conservation and taking up alternative livelihood options. State responses to drought over the last century reflect the general South African pattern of racially divided and unjust policies relating to resource access. Historically the state provided considerable support to white commercial farmers. This support was frequently contradictory in its aims and generally was inadequate to enable farmers to cope with drought. Since the advent of democracy in 1994, the state has intervened less, with some support extended to previously disadvantaged and poor communal farmers. Climate change predictions suggest an increase in drought, suggesting that the adoption of mitigating strategies should be a matter of urgency. To do this South Africa needs to build social and institutional capacity, strive for better economic and environmental sustainability, embed drought-coping mechanisms into land restitution policy to ensure the success of this programme, and acknowledge the diversity of the agricultural sector.
Water resources in the Klein Karoo: the challenge of sustainable development in a water-scarce area
Authors: Le Maitre David , Colvin Christine , Maherry Ashton
Published: April 2009

The Klein Karoo is situated in the Western Cape, South Africa, and is characterised by low rainfall (100–450 mm yr–1). The Klein Karoo is situated in the primary catchment of the Gouritz River. The mean annual runoff (MAR) for the three major tributaries of the Gouritz River arising in or feeding the Klein Karoo (Touws, Gamka, Olifants) is 540 Mm3 yr–1. Groundwater recharge in the three Klein Karoo catchments is ±257 Mm3 yr–1, but only a portion of this reaches the rivers. The very variable flows result in low 1:50 year yield of 161 Mm3 (30% of MAR). The current demand for water in these catchments is 182 Mm3 yr–1, which exceeds the yield, and demand is projected to increase between 23% and 150% by 2025. Changes in the approach to water management are required, including improving the efficiency of irrigation and land restoration to improve water infiltration and reduce soil erosion. We believe that it is time to change to a water management approach that is designed to anticipate and manage the inherent variability in water resources in the Klein Karoo, thereby placing the region on a path to sustainable development.
Drought, climate change and vegetation response in the succulent karoo, South Africa
Authors: Hoffman M.T. , Carrick P.J. , Gillson L. , West A.G.
Published: April 2009

For the winter-rainfall region of South Africa, the frequency of drought is predicted to increase over the next 100 years, with dire consequences for the vegetation of this biodiversity hotspot. We analysed historical 20th century rainfall records for six rainfall stations within the succulent karoo biome to determine if the signal of increasing drought frequency is already apparent, and whether mean annual rainfall is decreasing. We found no evidence for a decrease either in mean annual rainfall or in the incidence of drought, as measured by the Standardised Precipitation Index (SPI) over the 20th century. Evidence points to a drying trend from 1900–1950 while no significant trend in rainfall and drought was found at most stations from 1951–2000. In a second analysis we synthesised the information concerning the response of adult succulent karoo biome plants and seedlings to extended drought conditions. General findings are that responses to drought differ between species, and that longevity is an important life history trait related to drought survival. Growth form is a poor predictor of drought response across the biome. There was a range of responses to drought among adult plants of various growth forms, and among non-succulent seedlings. Leaf-succulent seedlings, however, exhibited phenomenal drought resistance, the majority surviving drought long after all the experimentally comparative non-succulent seedlings had died. Our synthesis showed that previous studies on the impact of drought on succulent karoo biome plants differ greatly in terms of their location, sampling design, measured values and plant responses. A suite of coordinated long-term field observations, experiments and models are therefore needed to assess the response of succulent karoo biome species to key drought events as they occur over time and to integrate this information into conservation planning.
Anti-Employer Blogging: An Overview of Legal and Ethical Issues
Authors: Markel Mike
Published: April 2009

Anti-employer blogs, those which criticize companies or their employees, are posing significant legal and ethical challenges for corporations. The important legal issue is the conflict between the employee's legal duty of loyalty to the employer and the employee's right to free speech. Although U.S. and state law describes what an employee may or may not say in a blog, corporations should encourage employees to contribute to the process of creating clear, reasonable policies that will help prevent expensive court cases. The important ethical issue concerning anti-employer blogs is whether an employee incurs an ethical duty of loyalty. In this article, I conclude that there is no such ethical duty. The legal duty of loyalty, explained in a company-written policy statement that employees must endorse as a condition of employment, offers the best means of protecting the legal and ethical rights of both employers and employees.
Presenting Consumer Technology with Pop: A Rhetorical and Ethnographic Exploration of Point-of-Purchase Advertising
Authors: Cross Geoffrey A.
Published: April 2009

Point-of-purchase advertising (POP) is responsible for half of the purchase decisions made in the store. Because of: 1) the influence of POP on the sale of technical consumer products and the economy; 2) our need to understand trends that shape technical and business communication; 3) the intermedial nature of POP (where spoken and written words work with place, visual image, physical structures, and multimedia integrated marketing campaigns); and 4) its theatrical and local nature, we need both a situated and theoretical exploration of POP. Drawing upon three months' participant observation in advertising, I describe a POP composing process in an integrated marketing campaign. Cognitive responses to layout and the interrelation of rhetorical canons are considered for preparing communication for a marketplace that is three-dimensional variegated, noisy, and peripatetic.
Composition Studies, Professional Writing and Empirical Research: A Skeptical View
Authors: Driscoll Dana Lynn
Published: April 2009

This article builds upon the work of Richard Haswell's “NCTE/CCCC's Recent War on Scholarship” by providing an alternative framework for empirical inquiry based on principles of skepticism. It examines the literature relating to empirical research and argues that one of the issues at hand is the perceived link of empirical research to positivism, which clashes with the dominant social constructivist paradigm. It draws upon classical rhetoric and the work of radial empiricist William James to formulate an alternative framework for empirical research based on skeptical principles.
Pelvic Organ Prolapse and Relationship with Skeletal Integrity
Authors: Pal Lubna
Published: April 2009

Health burden related to osteoporotic fractures in an aging female population far exceeds that imposed by other chronic disorders such as cardiovascular disease and breast cancer. Bone mineral density assessment and clinical risk factors provide independent insights into fracture risk in individuals. A finite list of clinical risk factors are identified as prognostic of fracture risk, namely among aging women, including low body mass, compromised reproductive physiology (e.g., prolonged periods of amenorrhea and early menopause), parental and personal histories of fracture, and alcohol and tobacco use. Pelvic organ prolapse is a common gynecologic entity and a contributor to age-related morbidities. The purpose of this review is to communicate data identifying pelvic organ prolapse as another clinical risk factor for fracture risk in postmenopausal women and to increase the caregiver's vigilance in anticipating and instituting preventive care strategies to a population (i.e., postmenopausal women with clinically appreciable pelvic organ prolapse) that may be at an enhanced lifetime risk for skeletal fractures.
Breast Cancer Diagnosis during Pregnancy
Authors: Litton Jennifer K , Theriault Richard L , Gonzalez-Angulo Ana M
Published: April 2009

Breast cancer diagnosed during pregnancy is a challenging situation for the patient and her medical team. As women are delaying childbirth, the incidence is expected to increase. Most of the data surrounding the diagnosis and treatment of cancer during pregnancy is in case reports and small cohort studies. However, the data continues to expand regarding the safety of systemic treatments during the second and third trimesters for both the mother and the fetus. In this article, the use of diagnostic imaging, procedures, surgery and chemotherapy are reviewed as well as prognosis and future pregnancies after the treatment for breast cancer.
Postpartum Depression: An Update
Authors: Friedman Susan Hatters , Resnick Phillip J
Published: April 2009

Postpartum depression occurs in at least one in seven new mothers, usually within the first 6 months after delivery. By the time of onset of postpartum depression, the mother has usually long since been discharged from the maternity hospital. Early identification and treatment of these mothers reduces both maternal and infant suffering. Careful risk–benefit decision-making regarding various treatment options in the postpartum should be discussed with the mother. Risks of untreated depression include poor bonding with the infant, lack of self care, infant neglect and infanticide.
Neonatal Outcomes in Relation to Timing of Repeat Cesarean Delivery at Term
Authors: Tuuli Methodius G , Odibo Anthony O
Published: April 2009

Evaluation of: Tita AT, Landon MB, Spong CY et al.: Timing of elective repeat cesarean delivery at term and neonatal outcomes. N. Engl. J. Med. 360(2), 111–120 (2009). The increasing rates of repeat cesarean delivery necessitate, more than ever, the need to time deliveries to optimize neonatal outcomes. A recent large multicenter cohort study demonstrated that, contrary to current recommendations, a high proportion of elective cesarean deliveries in the USA are performed before 39 weeks' gestation. These early deliveries are associated with a significant increase in several adverse neonatal events, including respiratory complications, treated hypoglycemia, newborn sepsis and admission to the neonatal intensive care unit. This, together with results of previous studies, supports the recommendation to delay elective delivery to 39 weeks' gestation. From the current data, it is uncertain whether delivery before 39 weeks' gestation with documented fetal lung maturity will prevent the increased neonatal morbidity.
Trauma in the Obstetrical Patient
Authors: Hill Christina C
Published: April 2009

Trauma complicates approximately 6–7% of all pregnancies and is associated with significant maternal and fetal morbidity and mortality. While the majority of trauma is minor, it is minor trauma that contributes to the majority of fetal mortality. Since virtually every organ system is affected anatomically and physiologically by pregnancy, it is important for healthcare providers who care for trauma victims to be aware of these changes. While assessment and resuscitation considers the existence of two patients, stabilization of the mother takes priority. Diagnostic and radiologic procedures should be used as indicated, with fetal exposure to radiation limited as much as possible. Management of the pregnant trauma victim requires a multidisciplinary approach in order to optimize outcome for mother and fetus. This review discusses the epidemiology, assessment and treatment of pregnant trauma patients and reviews areas where prevention efforts may be focused.
Chemical modification of Art v 1, a major mugwort pollen allergen, by cis-aconitylation and citraconylation
Authors: Stanic Dragana , Burazer Lidija , Gavrovic-Jankulovic Marija , Jankov Ratko , Cirkovic-Velickovic Tanja
Published: April 2009

Art v 1 is the major allergen of mugwort (Artemisia vulgaris) pollen, a significant cause of hay fever all over Europe. Specific immunotherapy is the only treatment modality for allergic disease. Application of modified allergens makes the treatment safer and more efficient. In this work, two out of three (citraconic anhydride, cis-aconitic anhydride, 2,3-dimethylmaleic anhydride) tested anhydrides were proven to be suitable for chemical modifications of allergens. Art v 1 was modified by cis-aconitylation and citraconylation in order to obtain derivatives of Art v 1 that may be suitable for further immunological testing. Acylation of Art v 1 gave derivatives (caaArt v 1 and citArt v 1) with about 80 % modified amino groups. The derivatives were in the monomeric form and had dramatically reduced pI values. Both derivatives were relatively stable at neutral pH values, while the acyl groups undergo hydrolysis under acidic conditions. Modification of allergens by cis-aconitylation and citraconylation could be a new tool for obtaining allergoids.
Inhibition of trypsin by heparin and dalteparin, a low molecular weight heparin
Authors: Bosnic Olivera , Gopcevic Kristina , Vrvic Miroslav , Karadzic Ivanka
Published: April 2009

The interaction between trypsin, a prototype S1 serine protease, with heparin and its low molecular weight derivative dalteparin were investigated. Direct inhibition of the proteolytic activity of trypsin by heparin and dalteparin, used in concentrations typical for their clinical application, was detected. The half-maximum inhibition of the trypsin activity was achieved at 15.25?1.22 ?g/mL for heparin and was estimated to be at 58.47?15.20 ?g/mL for dalteparin. Kinetic analyses showed that heparin and its low molecular weight derivative dalteparin inhibited trypsin by occupation of an exosite, producing noncompetitive and mixed inhibition, respectively. Heparin as a noncompetitive inhibitor with constant of inhibition Ki1,2 = 0.151?0.019 ?M and dalteparin with Ki1 = 0.202?0.030 ?M and Ki2 = 0.463?0.069 ?M in mixed inhibition both represent moderate inhibitors of serine protease trypsin. The obtained constants of inhibition indicate that under the clinically applied concentrations of heparin and dalteparin, trypsins and their homolog S1 serine proteases could be directly inhibited, influencing the delicate control of proteolytic reactions in homeostasis.
Composite material based on an ablative phenolic resin and carbon fibers
Authors: Srebrenkoska Vineta , Bogoeva-Gaceva Gordana , Dimeski Dimko
Published: April 2009

In this study, a technological procedure for the production of a molding compound based on short carbon fibers and an ablative phenol-formaldehyde resin for high temperature application was optimized. The starting raw materials were characterized and molding compounds with different fiber/ /matrix ratios and different fiber lengths were obtained. From the different laboratory samples, molded parts were made by thermo-compression. The basic mechanical and thermal properties of the composites were determined. From the obtained results, the optimal fiber/matrix ratio was determined for a production of molding compound for high temperature application. The molding process of the composite material was optimized and all the parameters for good mechanical properties and high thermal stability of the composite were obtained. Optimization of the composite molding process was performed by the application of a numerical method for a planned experiment, i.e., a full three-factorial experimental design with variance of all three parameters (fiber length, temperature and time of the press cycle) on two levels. The obtained mechanical properties (flexural strength: 247 MPa, modulus: 27.6 GPa, impact resistance: 110 (for test moldings 10 mm?10 mm) and 91 kJ/m2 (for test moldings 15 mm?15 mm)) justified the application of this composite material in the automotive, leisure, military and other industries where high temperature resistance and high mechanical strength is required.
Association of Smoking Status, Weight Change, and Incident Metabolic Syndrome in Men: A 3-Year Follow-Up Study
Authors: Kim Byung Jin , Kim Bum Soo , Sung Ki Chul , Kang Jin Ho , Lee Man Ho , Park Jung Ro
Published: April 2009

OBJECTIVE

We investigated the incidence of the metabolic syndrome and assessed the effect of smoking status and weight change on incident metabolic syndrome.

RESEARCH DESIGN AND METHODS

This study included 4,542 men without metabolic syndrome at baseline who were followed for an average of 3 years. Subjects were divided into four categories according to smoking status at baseline and at the 3-year follow-up.

RESULTS

The overall incidence of metabolic syndrome was 10.6%: 8.0% in nonsmokers, 7.1% in new smokers, 17.1% in ex-smokers, and 13.9% in sustained smokers (P < 0.001). In a multivariate regression model, ex-smokers had significantly increased odds for incident metabolic syndrome with a mean 1.45 (95% CI 1.06–1.98) compared with sustained smokers. This was no longer significant after including weight change.

CONCLUSIONS

Smoking cessation within 3 years may be a higher risk factor for incident metabolic syndrome than sustained smoking, indicating that weight control in ex-smokers is critical to attenuate the additional risk for incident metabolic syndrome.
Reference Values for Continuous Glucose Monitoring in Chinese Subjects
Authors: Zhou Jian , Li Hong , Ran Xingwu , Yang Wenying , Li Qiang , Peng Yongde , Li Yanbing , Gao Xin , Luan Xiaojun , Wang Weiqing , Jia Weiping
Published: April 2009

OBJECTIVE

The widespread clinical application of continuous glucose monitoring (CGM) is limited by the lack of generally accepted reference values. This multicenter study aims to establish preliminary normal reference values for CGM parameters in a sample of healthy Chinese subjects.

RESEARCH DESIGN AND METHODS

A total of 434 healthy individuals with normal glucose regulation completed a 3-day period of glucose monitoring using a CGM system. The 24-h mean blood glucose (24-h MBG) and the percentage of time that subjects' blood glucose levels were ≥140 mg/dl (PT140) and ≤70 mg/dl (PT70) within 24 h were analyzed.

RESULTS

There was excellent compliance of finger stick blood glucose values with CGM measurements for subjects. Among the 434 subjects, the daily blood glucose varied from 76.9 ± 11.3 to 144.2 ± 23.2 mg/dl. The 24-h MBG, PT140, and PT70 were 104 ± 10 mg/dl, 4.1 ± 5.8%, and 2.4 ± 5.3%, respectively. As for these parameters, no significant differences were found between men and women. The 95th percentile values were adopted as the upper limits of CGM parameters, which revealed 119 mg/dl (6.6 mmol/l) for 24-h MBG, 17.1% for PT140, and 11.7% for PT70.

CONCLUSIONS

We recommend a 24-h MBG value <119 mg/dl, PT140 <17% (4 h), and PT70 <12% (3 h) as normal ranges for the Chinese population.
Oxidative Stress and Insulin Resistance
Authors: Park Kyong , Gross Myron , Lee Duk-Hee , Holvoet Paul , Himes John H. , Shikany James M. , Jacobs David R.
Published: April 2009

OBJECTIVE

Although cumulative evidence suggests that increased oxidative stress may lead to insulin resistance in vivo or in vitro, community-based studies are scarce. This study examined the longitudinal relationships of oxidative stress biomarkers with the development of insulin resistance and whether these relationships were independent of obesity in nondiabetic young adults.

RESEARCH DESIGN AND METHODS

Biomarkers of oxidative stress (F2-isoprostanes [F2Isop] and oxidized LDL [oxLDL]), insulin resistance (the homeostasis model assessment of insulin resistance [HOMA-IR]), and various fatness measures (BMI, waist circumference, and estimated percent fat) were obtained in a population-based observational study (Coronary Artery Risk Development in Young Adults) and its ancillary study (Young Adult Longitudinal Trends in Antioxidants) during 2000–2006.

RESULTS

There were substantial increases in estimated mean HOMA-IR over time. OxLDL and F2Isop showed little association with each other. Mean evolving HOMA-IR increased with increasing levels of oxidative stress markers (P < 0.001 for oxLDL and P = 0.06 for F2Isop), measured in 2000–2001. After additional adjustment for adiposity, a positive association between oxLDL and HOMA-IR was strongly evident, whereas the association between F2Isop and HOMA-IR was not.

CONCLUSIONS

We observed positive associations between each of two oxidative stress markers and insulin resistance. The association with oxidized LDL was independent of obesity, but that with F2Isop was not.
Ultrastructure and cytochemistry of vitellogenesis in Wenyonia virilis Woodland, 1923 (Cestoda, Caryophyllidea)
Authors: Świderski Zdzisław , Młocicki Daniel , Mackiewicz John , Miquel Jordi , Ibraheem Mohammed , Bruňanská Magdalena
Published: April 2009

Vitellogenesis in Wenyonia virilis was examined by transmission electron microscopy (TEM), including the cytochemical detection of glycogen at the ultrastructural level with the periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-SP) technique. Mature vitelline follicles have cells in various stages of development, progressing from immature cells of gonial type near the periphery of the follicle to maturing and mature vitellocytes towards the centre. Maturation is characterized by: (1) increase in cell volume; (2) increase in nuclear surface area restoring the N/C (nucleo-cytoplasmic) ratio; (3) nucleolar transformation; (4) extensive development of parallel cisternae of GER, the shell-protein producing units; (5) development of Golgi complexes, engaged in shell-granule/shell-globule formation and packaging; (6) synthesis and storage of glycogen in the cytoplasm; (7) simultaneous, independent formation and storage of intranuclear glycogen; (8) continuous fusion of small shell-granules into larger shell-globules and fusion of these into large shell-globule clusters with a progressive increase in the number and size of the latter; and (9) disintegration of GER in the medial layer of vitellocyte cytoplasm, degenerative changes and accumulation of glycogen and shell-globule clusters within the cytoplasm. The functional significance of numerous shell-globule clusters and the relatively small amount of nuclear and cytoplasmic glycogen is analysed. Unlike vitellogenesis of other caryophyllids, the nuclear glycogen of mature vitellocytes in W. virilis is randomly dispersed in the nucleoplasm and never forms a high central accumulation, the so-called “nuclear vacuole”. The nutritive function of vitellocytes appears greatly reduced in W. virilis, a fact perhaps related to the intrauterine development of the early embryos. The ultrastructure of vitellogenesis in W. virilis is compared with that in other lower cestodes, both monozoic and polyzoic. Conclusions concerning interrelationships of the vitellogenesis pattern of the ultrastructural cytochemistry of mature vitellocytes of W. virilis to intrauterine embryonation, absence of uterine glands and an extensive uterus characteristic for this species, are drawn and discussed.
Genetic markers to gastrointestinal nematode resistance in sheep: a review
Authors: Krawczyk A. , Słota E.
Published: April 2009

Nematode parasites are the major animal health constraint in sheep production on pasture and cause serious economic losses. Because of failure of anthelmintic drenches, a major research effort has been underway to examine alternatives to chemical control. One of them is selecting sheep which are genetically resistant to parasitic nematodes. However, this last is not widely practiced because of the difficulty of measuring parasite resistance which mostly relies on indirect criteria such as number of nematode eggs passed in the sheep faeces (FEC) packed cell volume (PCV) or enhanced number of eosinophils in peripheral blood. Despite the well known host immune reaction it has been impossible to standardize any immunological parameter and use it as an indicator of parasitic infection. The aim of finding some genetic markers associated with resistance/susceptibility to nematodes is to make diagnostic work easier and conduct an earlier selection of desirable genotypes. However, searching for reliable genetic markers is rather difficult due to different sheep’s manifestation of resistance to either the adult or larval stages of the same parasite species and against the same parasitic stage and various manifestations of the immune responses and antigens against parasites. This review summarizes findings reported in the literature relating to genetic markers to gastrointestinal nematodes resistance in sheep.
Activity of four entomopathogenic nematode species against different developmental stages of Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera, Chrysomelidae)
Authors: Trdan S. , Vidrih M. , Andjus L. , Laznik Ž.
Published: April 2009

Four entomopathogenic nematode species (Steinernema feltiae, S. carpocapsae, Heterorhabditis bacteriophora, and H. megidis) were tested in a laboratory bioassay for the efficacy of these pathogens in controlling the larvae and adults of the Colorado potato beetle, Leptinotarsa decemlineata. The main aim of the study was to develop an efficient sustainable control method against the pest. With this we could develop a strategy of potato production with the intention of diminishing or even preventing the appearance of pest resistance to insecticides. The activity of these biological agents was assessed at three different temperatures (15, 20, and 25 °C) and three concentrations (200, 1000, and 2000 infective juveniles per individual). Mortality of three stages (young and old larvae and adults) was determined 2, 4, and 7 days after treatment. At 15 °C entomopathogenic nematodes showed the lowest efficacy against all insect stages. No significant differences in efficacy was determined at 20 and 25 °C as all nematodes caused prompt death of all stages. At all temperatures young larvae were most susceptible. However, when controlling overwintered adults for the purpose of preventing the mass appearance of Colorado potato beetle, we recommend an application of higher concentrations of S. feltiae suspension.
Influence of the genetic pattern and sex of mice in experimental lagochilascariosis
Authors: Prudente M. , Freitas J. , Ribeiro E. , Carvalhaes M.
Published: April 2009

We studied experimental lagochilascariosis in male and female mice of four strains. The survival ratio and number of larvae recovered varied: B10.A and C57BL/6 mice had the highest number of larvae 90 days after infection and the lowest survival ratio at 345 days of infection. BALB/c mice had an intermediate survival ratio and number of larvae. A/J mice had the lowest number of larvae and the highest survival ratio. Our findings suggest that resistance to Lagochilascaris minor is not linked to the H-2a region because both susceptible B10.A and resistant A/J mice express the H-2a haplotype. However, the pattern of mortality and larvae recovered that we observed in C57BL/6 mice, which possess the same genetic background as B10.A, indicates that the background genotype does affect the outcome of lagochilascariosis in mice. This study demonstrates that the genetic background, but not H-2a or sex, determine the outcome of lagochilascariosis in mice.
First report of the genus Heterorhabditis (Nematoda: Heterorhabditidae) from continental Portugal
Authors: Valadas V. , Vieira P. , Oliveira S. , Mota M.
Published: April 2009

Until recently, the only entomopathogenic nematode (EPN) species reported from continental Portugal, was of the genus Steinernema. Following a national survey of EPNs in continental Portugal, several natural and managed habitats have been surveyed in the southern part of the country. From 57 soil samples collected using the Galleria mellonella trapping method, three samples yielded EPN. Morphological characterization and sequence analysis of the ITS regions of ribosomal DNA allowed the identification of EPN isolates as Heterorhabditis bacteriophora, representing the first report of this genus for continental Portugal.
Strategies in Prevention of Preharvest Aflatoxin Contamination in Peanuts: Aflatoxin Biosynthesis, Genetics and Genomics
Authors: Guo Baozhu , Yu Jiujiang , Holbrook C. Corley , Cleveland Thomas E. , Nierman William C. , Scully Brian T.
Published: April 2009

Peanut (Arachis hypogaea L.), or groundnut, is an important crop economically and nutritionally in many tropical and subtropical areas of the world. It is also one of the most susceptible host crops to Aspergillus flavus resulting in aflatoxin contamination. The prevention or elimination of aflatoxin contamination in preharvest and postharvest crops is a serious challenge facing scientists. The recent International Conference on Groundnut Aflatoxin Management and Genomics held in Guangzhou, China, provided an international forum for discussions on the latest accomplishments, the development of strategies, and the initiation of cooperative research for the prevention of aflatoxin contamination. This review summarizes the progress in genetic and genomic research of peanuts and the toxin-producing fungus A. flavus. In particular, the pathway for production and the genetic regulation of afaltoxin, and the peanut-Aspergillus interaction are discussed. The use of a peanut-Aspergillus microarray will help scientists to study the crop-pathogen interaction; aids in the identification of genes involved in both fungal invasion and crop resistance, and ultimately enhance research to find solutions that prevent aflatoxin contamination in agricultural commodities.
Review of Immunological Methods for the Quantification of Aflatoxins in Peanut and Other Foods
Authors: Waliyar Farid , Reddy S. V. , Lava-Kumar P.
Published: April 2009

Aflatoxin contamination is widespread in staple crops like peanut, maize, sorghum, pearl millet, chillies, pistachio, cassava etc., and compromises the safety of food and feed supplies. It is important to be able to detect and quantify aflatoxins in commodities to protect human and animal health. Many different methods, including antibody-based ones, are available for quantitative estimation of aflatoxins. However, most of these methods such as HPLC, HPTLC, and TLC are expensive and/or difficult to use in developed countries. Using the state-of-the-art facilities at ICRISAT, we developed polyclonal and monoclonal antibodies for the detection of total aflatoxins, aflatoxin B1 and M1 (secreted in milk). These were used to develop a simple and inexpensive competitive enzyme-linked immunosorbent assays (cELISA) that has lower detection limits (1.0 µg/kg) and cost (about $1 per sample) less than other available methods. More than 100 samples can be analyzed in a day. These tests have provided a unique opportunity for ICRISAT and its partners to conduct field studies to select resistant genotypes, identify high risk populations and determine the dietary sources to stimulate appropriate interventions to enhance the food and human health safety, trade and thereby farmers' income.
The U.S. Breeding Program to Develop Peanut with Drought Tolerance and Reduced Aflatoxin Contamination
Authors: Holbrook C. Corley , Guo B. Z. , Wilson D. M. , Timper P.
Published: April 2009

Aflatoxin contamination costs the U.S. peanut (Arachis hypogaea L.) industry over $20 million annually. The development of peanut cultivars with resistance to preharvest aflatoxin contamination (PAC) would reduce these costs. Screening techniques have been developed that can measure genetic differences in aflatoxin contamination and they have been used to identify accessions that exhibited relatively low PAC in multiple environments. Significant reductions in PAC have been identified in peanut genotypes with drought tolerance. These sources of resistance to PAC have been crossed with cultivars and breeding lines that have high yield, acceptable grade, and resistance to spotted wilt caused by Tomato spotted wilt tospovirus (TSWV). Due to the large environmental variation in PAC, breeding populations can only be evaluated in late generations when there is less heterozygosity and adequate numbers of seed are available for field testing using multiple replications. Evaluation of numerous breeding populations has identified several families and individual breeding lines with relatively low PAC, relatively high yield, and acceptable levels of resistance to TSWV. To increase breeding efficiency, studies on mechanisms of resistance to PAC are being conducted. The most promising mechanisms identified thus far are resistance to drought and resistance to the peanut root-knot nematode. Late generation breeding lines have been developed with resistance to drought, several of which also exhibited reduced aflatoxin contamination in multiple environments. Tifguard, the first cultivar with high levels of resistance to both TSWV and the peanut root-knot nematode [Meloidogyne arenaria (Neal) Chitwood race 1] was released from this program. Testing is ongoing to determine if this cultivar can be used to reduce aflatoxin contamination in nematode infested fields.
Influence of Digging Date and Fungicide Program on Canopy Defoliation and Pod Yield of Peanut (Arachis hypogaea L.)
Authors: Carley Danésha S. , Jordan David L. , Shew Barbara B. , Sutton Turner B. , Dharmasri L. Cecil , Brandenburg Rick L.
Published: April 2009

Although response can be variable and is dependant upon many factors, digging peanut as little as 1 wk prior to or 1 wk following optimum maturity can result in substantial reductions in pod yield. While growers often assume that harvest should be initiated prior to optimum maturity in fields with high levels of canopy defoliation, there is no clear threshold where gains in pod weight and grade are offset by losses due to pod shedding. Moreover, yield loss relationships for foliar diseases have not been characterized for modern virginia market-type cultivars. Determining interactions between digging date and peanut canopy defoliation would assist growers and their advisors in making more informed decisions on when to initiate harvest to avoid yield loss. Research conducted from 2004–2005 in North Carolina established a range of defoliation levels in a total of seven fields. Fungicides were applied on a bi-weekly schedule from early July through mid-September, or were applied two times in July, or were not applied. Plots were dug early, 6 to 12 days before estimated optimum maturity, or at optimum maturity, as determined by the hull-scrape method. Although interactions between digging date and fungicide program were found in some cases, digging date and fungicide program effects often varied independently. A general recommendation of the percentage of canopy defoliation justifying early digging to prevent yield loss could not be determined from this research. However, data from these experiments reinforce the value of controlling early leaf spot, late leaf spot, and web blotch with timely fungicide applications and the importance of digging at optimum pod maturation for more recently released virginia market-type peanut.
Influence of Application Variables on Peanut (Arachis hypogaea L.) Response to Prohexadione Calcium
Authors: Jordan David L. , Nuti Russell C. , Beam Joshua B. , Lancaster Sarah H. , Lanier James E. , Johnson P. Dewayne
Published: April 2009

Prohexadione calcium retards peanut vegetative vine growth, improves row visibility, and potentially reduces pod shed, thus increasing pod yield compared with non-treated peanut. Although prohexadione calcium has been registered for use in peanut for the past decade, practitioners continue to express a range of questions about use including banded application, compatibility with other agrichemcials, and interactions of application rate and timing. In experiments over multiple years, applying prohexadione calcium to lateral branches only of peanut increased row visibility compared with banded applications over main stems or broadcast applications over the entire peanut canopy. Similarly, when using different spray nozzle configurations, greater row visibility was noted when the highest rate of prohexadione calcium was applied over lateral branches compared with broadcast applications of a uniform rate across all spray nozzles or when the highest rate was delivered to main stems. Delaying the first of two sequential applications of prohexadione calcium 1 wk after 50% row closure resulted in reduced row visibility regardless of application rate when compared with sequential applications initiated at 50% row closure. Applying prohexadione calcium within 2 to 3 wks prior to digging and vine inversion resulted in minor increases in improved row visibility and did not affect pod yield. Efficacy of prohexadione calcium was not affected by tank mixing with pyraclostrobin or 2,4-DB.
Time course for autoregulation recovery following severe traumatic brain injury
Authors: Sviri Gill E. , Aaslid Rune , Douville Colleen M. , Moore Anne , Newell David W.
Published: April 2009

Object

The aim of the present study was to evaluate the time course for cerebral autoregulation (AR) recovery following severe traumatic brain injury (TBI)

Methods

Thirty-six patients (27 males and 9 females, mean ± SEM age 33 ± 15.1 years) with severe TBI underwent serial dynamic AR studies with leg cuff deflation as a stimulus, until recovery of the AR responses was measured.

Results

The AR was impaired (AR index < 2.8) in 30 (83%) of 36 patients on Days 3–5 after injury, and in 19 individuals (53%) impairments were found on Days 9–11 after the injury. Nine (25%) of 36 patients exhibited a poor AR response (AR index < 1) on postinjury Days 12–14, which eventually recovered on Days 15–23. Fifty-eight percent of the patients with a Glasgow Coma Scale score of 3–5, 50% of those with diffuse brain injury, 54% of those with elevated intracranial pressure, and 40% of those with poor outcome had no AR recovery in the first 11 days after injury.

Conclusions

Autoregulation recovery after severe TBI can be delayed, and failure to recover during the 2nd week after injury occurs mainly in patients with a lower Glasgow Coma Scale score, diffuse brain injury, elevated ICP, or unfavorable outcome. The finding suggests that perfusion pressure management should be considered in some of the patients for a period of at least 2 weeks.
Use of the h index in neurosurgery
Authors: Lee Janet , Kraus Kristin L. , Couldwell William T.
Published: April 2009

Object

Assessing academic productivity through simple quantification may overlook key information, and the use of statistical enumeration of academic output is growing. The h index, which incorporates both the total number of publications and the citations of those publications, has been recently proposed as an objective measure of academic productivity. The authors used several tools to calculate the h index for academic neurosurgeons to provide a basis for evaluating publishing by physicians.

Methods

The h index of randomly selected academic neurosurgeons from a sample of one-third of the academic programs in the US was calculated using data from Google Scholar and from the Scopus database. The mean h index for each academic rank was determined. The h indices were also correlated with various other factors (such as time spent practicing neurosurgery, authorship position) to identify how these factors influenced the h index. The h indices were then compared with other citation statistics to evaluate the robustness of this metric. Finally, h indices were also calculated for a sampling of physicians in other medical specialties for comparison.

Results

As expected, the h index increased with academic rank and there was a statistically significant difference between each rank. A weighting based on position of authorship did not affect h indices. The h index was positively correlated with time since American Board of Neurological Surgery certification, and it was also correlated with other citation metrics. A comparison among medical specialties supports the assertion that h index values may not be comparable between fields, even closely related specialties.

Conclusions

The h index appears to be a robust statistic for comparing academic output of neurosurgeons. Within the field of academic neurosurgery, clear differences of h indices between academic ranks exist. On average, an increase of the h index by 5 appears to correspond to the next highest academic rank, with the exception of chairperson. The h index can be used as a tool, along with other evaluations, to evaluate an individual's productivity in the academic advancement process within the field of neurosurgery but should not be used for comparisons across medical specialties.
Effect of WT1 gene silencing on the tumorigenicity of human glioblastoma multiforme cells
Authors: Clark Aaron J. , Ware Joy L. , Chen Mike Y. , Graf Martin R. , Van Meter Timothy E. , Dos Santos Wagner G. , Fillmore Helen L. , Broaddus William C.
Published: April 2009

Object

Wilms tumor 1 (WT1) is overexpressed in many human cancers, including glioblastoma multiforme (GBM). In another study, the authors showed that transient WT1 silencing increases the radiosensitivity of glioma cells. Studies of nonglioma cell lines have demonstrated that WT1 promotes cell proliferation and survival; however, this ability has not been rigorously analyzed in human GBM.

Methods

The authors tested the efficacy of 2 sequences of short hairpin RNA (shRNA) directed against WT1 in U251MG human GBM cells and found that 1 sequence was capable of stably silencing WT1 expression. They then evaluated the effect of WT1 silencing on cellular proliferation, invasion, and in vivo tumor formation.

Results

Stable WT1-shRNA expression significantly decreased the proliferation of U251MG cells in vitro as demonstrated by both an adenosine 5′-triphosphate–based viability assay and tritiated thymidine uptake. Furthermore, stable WT1 silencing caused significantly slower growth after the subcutaneous inoculation of tumor cells in the flanks of athymic nude mice and was associated with an increased latency period.

Conclusions

Data in this study provide proof of the principle that downregulation of WT1 causes decreased tumorigenicity of a GBM cell line in vitro and in vivo and suggest that WT1 is a promising target for novel molecular GBM therapies, perhaps in combination with standard treatment modalities.