bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Influencing Early Childhood Caries of Cleft Lip and/or Palate Children Aged 18 to 36 Months in Southern Thailand
Authors: Mutarai Teerapong , Ritthagol Wipapun , Hunsrisakhun Jaranya
Published: September 2008

Objective:

To clarify whether oral health care behavior or oral cleft status influences early childhood caries in southern Thailand cleft children.

Design:

A comparative cross-sectional study.

Patients, Participants:

A total of 138 southern Thai children aged 18 to 36 months comprised two groups of 69 participants, one with cleft lip and/or palate and controls with no cleft.

Methods:

All children were examined for early childhood caries by using the severity (DMFT/tooth) index. A structured interview was conducted among caregivers, and then multiple regression analysis was applied.

Results:

Children with oral clefts had a larger number of early childhood caries (ECC) and poorer feeding habits than those without. From a structured questionnaire, the caregivers of children with clefts exercised poorer oral health behavior than those of the controls, but the cleft status was not an important factor for caries prevalence when oral health behaviors were controlled. Multivariate analysis showed that sweetened bottled milk consumption, night-time feeding habit, and frequent sugary food consumption were the variables significantly associated with dental caries.

Conclusions:

Children with oral clefts in southern Thailand had greater caries experience when compared with noncleft subjects. However, cleft status was not significant for ECC, and night-time feeding habit was the most important factor for higher ECC in children with clefts.
Oral and Nasal Malodor in Patients with and without Cleft Lip and Palate Who Had Undergone Orthodontic Therapy
Authors: Doruk Cenk , Öztürk Fırat , Özdemir Hakan , Nalçaci Ruhi
Published: September 2008

Objective:

To compare oral and nasal malodor in patients with and without cleft lip and palate (CLP) who had undergone orthodontic therapy.

Setting:

University of Cumhuriyet, Sivas, Turkey.

Patients:

The study included 33 patients. Group 1 was composed of 11 patients with CLP. Measurements were taken while they were undergoing treatment with orthodontic fixed appliances. Group 2 included 11 individuals without CLP; measurements were taken during fixed orthodontic therapy. Group 3 consisted of 11 individuals without CLP who did not receive orthodontic therapy.

Intervention:

Oral malodor, nasal malodor, Gingival Index, Plaque Index, and probing depths were evaluated in each group.

Results:

Plaque Index, Gingival Index, and probing depths showed no significant differences between groups 1 and 2. In contrast, oral malodor was significantly different between the two groups (p < .05). Groups 2 and 3 showed differences in gingival and plaque indices but not in probing depths and oral malodor. All healthy nostrils in Group 1, Group 2, and Group 3 were significantly different from affected nostrils in the CLP patients. There was significant malodor in affected nostrils when compared with nonaffected nostrils in group 1 (p < .05).

Conclusion:

Oral malodor was increased in patients with CLP. Nasal malodor level was also higher in affected nostrils of the CLP patients compared to nostrils of healthy subjects.
Seasonal Variation and Regional Distribution of Cleft Lip and Palate in Zambia
Authors: Elliott Rachael Fels , Jovic Goran , Beveridge Massey
Published: September 2008

Objective:

To assess variations in seasonality and regional distribution of orofacial clefts in babies born in Zambia.

Design:

A retrospective chart review was done using records of all cleft procedures performed by the only plastic surgeon in Zambia (G.J.). Delivery data from the University Teaching Hospital (UTH) were also examined to estimate the birth prevalence of orofacial clefts (55,108 live births between 2001 and 2005).

Patients:

All cleft patients operated in Zambia from 2000 to 2006 (413 patients).

Results:

A low birth prevalence of clefts (1/4239 live births) was found using UTH delivery data. Surgical data showed no difference for the frequency of one gender over another overall (M:F ratio is 1.04; p  =  .70). More bilateral clefts occurred in cleft lip and palate (CLP) patients than in cleft lip (CL) patients (p < .01), and more unilateral left-sided clefts occurred in CL than in CLP patients (p  =  .03). The data reflected seasonal variation in month of birth of cleft lip with or without cleft palate (CL±P) patients (p < .01), with a peak in April and May and more births in March through August (57.2%) than in September through February (42.8%). There was regional variation in cleft births among the nine Zambian provinces (p < .01).

Conclusions:

This study shows seasonal variation in clefts that may be explained, at least in part, by environmental factors affecting the development of CL±P. Access to treatment is likely the major determinant of regional disparity in clefts. These results provide a basis for further epidemiological studies of orofacial clefts in Zambia.
TGFA/TAQ I Polymorphism in Nonsyndromic Cleft Lip and Palate Patients from Rio Grande Do Sul, Brazil
Authors: Ehlers Bertoja Ângela , Sampaio Alho Clarice , De França Everaldo , Menegotto Beatriz , Miriam Robinson Wanyce
Published: September 2008

Objective:

To test the TGFA/Taq I polymorphism in the development of nonsyndromic cleft lip and palate.

Design And Setting:

The research was based on a case-control study, including nonsyndromic cleft lip and palate patients (140 individuals) and a control sample of unaffected individuals (142) to ascertain the absence or presence of genic mutation at the TGFA locus.

Interventions:

The DNA of carriers of nonsyndromic cleft lip with or without cleft palate was obtained by buccal swab, and the DNA of the control group was extracted from peripheral blood leucocytes. TGFA/Taq I polymorphism was determined genetically by polymerase chain reaction using specific primers and fragment digestion with Taq I restriction enzyme.

Results:

No significant association was detected when patients and controls were compared with the genotype for TGFA/Taq I polymorphism.

Conclusion:

Mutations in TGFA gene have no association with nonsyndromic cleft lip and palate in the sample from Rio Grande do Sul. Therefore, based on this study, it is not possible to determine the role played by TGFA in the expression of cleft lip and palate.
Effect of Fertilizer Nitrogen on Weed Emergence and Growth
Authors: Sweeney Amy E. , Renner Karen A. , Laboski Carrie , Davis Adam
Published: September 2008

The timing of nitrogen (N) fertilizer application may influence germination, emergence, and competitiveness of weeds. Research was conducted to determine the influence of total inorganic soil N (Nit) on the germination, emergence, and growth of five weed species. In a greenhouse experiment, seed of five weed species were exposed to four levels of N, and seed germination was measured. In the field, urea ammonium nitrate (UAN 28%) was applied at multiple rates at three spring timings, and Nit, weed emergence, and growth were measured for 21 to 35 d after application (DAA). Germination of the four dicotyledonous and single grass species was not stimulated by 450 ppmw of N compared with the untreated control. In the field, Nitof 112 or 168 kg N ha−1, measured at 7 and 21 DAA, was always greater than Nitin the untreated control. The duration of the available N pulse in the upper 8 cm of soil was dependent on N application rate and timing. At 8 to 16 cm of soil depth, Nitwas greater when 168 kg N ha−1was applied compared with no N at 21 and 35 DAA in 2004. Emergence of common lambsquarters increased as N application rate increased for each application date in 2003, but not in 2004. Emergence of ladysthumb increased with N application rate for the April 15, 2003, date; emergence of giant foxtail increased with N application rate for the April 6, 2004, date. Weed biomass was always greater when 168 kg N ha−1was applied compared with no N, and at four of six N application dates, when 112 kg N ha−1was applied. This research shows that spring N fertilizer applications increase Nitand weed growth, but the influence of N on weed emergence is dependent on the weed species, seed source, and environmental conditions.
Importance of the P106S Target-Site Mutation in Conferring Resistance to Glyphosate in a Goosegrass (Eleusine indica) Population from the Philippines
Authors: Kaundun Shiv S. , Zelaya Ian A. , Dale Richard P. , Lycett Amy J. , Carter Patrice , Sharples Kate R. , McIndoe Eddie
Published: September 2008

Few studies on herbicide resistance report data to establish unambiguously the correlation between genotype and phenotype. Here we report on the importance of the EPSPS prolyl106point mutation to serine (P106S) in conferring resistance to glyphosate in a goosegrass population from Davao, Mindanao Island, the Philippines (Davao). Initial rate-response studies showed clear survivors within the Davao population at glyphosate rates that completely controlled the standard sensitive goosegrass population (STD1). Assessment of potential resistance mechanisms identified the presence of P106S mutant individuals in the Davao population. Polymerase chain reaction (PCR) amplification of specific alleles (PASA) analysis established that the mixed-resistant Davao population was comprised of 39.1% homozygous proline wild-type (PP106), 3.3% heterozygous serine mutant (PS106), and 57.6% homozygous serine mutant (SS106) genotypes. Further rate-response studies on plants with a predetermined genotype estimated the Davao SS106 individuals to be approximately 2-fold more resistant to glyphosate compared to Davao PP106 individuals. Extensive analysis at different goosegrass growth stages and glyphosate rates established strong correlation (P < 0.001) between presence of P106S in EPSPS and the resistant phenotype. Importantly, no differences in the pattern of absorbed or translocated14C–glyphosate were observed between PP106 and SS106 Davao genotypes or Davao and STD1 individuals, suggesting that glyphosate resistance in the Davao population was attributable to an altered target site mechanism. This study demonstrates that whilst P106S in EPSPS confers a moderate resistance level to glyphosate, the mechanism is sufficient to endow glyphosate failure at the recommended field rates.
Chemical and Physical Defense of Weed Seeds in Relation to Soil Seedbank Persistence
Authors: Davis Adam S. , Schutte Brian J. , Iannuzzi James , Renner Karen A.
Published: September 2008

Effective weed seedbank management requires mechanistic understanding of ecological determinants of seed persistence in the soil seedbank. Chemical and physical defense of common lambsquarters, field pennycress, giant foxtail, kochia, velvetleaf, and yellow foxtail seeds were quantified in relation to short- and long-term seedbank persistence. Seed content ofortho-dihydroxyphenols (o-DHP), a class of putative seed defense compounds, varied more than threefold between the least protected species (common lambsquarters, 9.2 µg g seed−1) and the most protected species (kochia, 34.1 µg g seed−1). Seedo-DHP was inversely related (r= −0.77, P < 0.001) to seed half-life in the soil and to short-term seed persistence in burial assays (r= −0.82, P < 0.05). The relative importance of chemical seed protection in comparison to physical seed protection, as represented by the ratio of seedo-DHP concentration to seed coat thickness, decreased linearly with increasing short-term seed persistence (r= −0.96, P < 0.01) and nonlinearly with increasing long-term seed persistence in the soil seedbank (y = 0.16 + 0.21/(0.0432 + x),R2= 0.99, P < 0.001). Mechanical damage to the seed coat, via piercing, slicing, or grinding treatments, increased short-term mortality during burial for all six species. Mortality of pierced seeds was negatively associated (r= −0.35, P < 0.05) with seed phenol concentration and positively associated with seed half-life (r= 0.42, P < 0.01) and seed coat thickness (r= 0.36, P < 0.05). Seed phenolics, as a class, supported the results foro-DHPs. Overall, these findings suggest a potential weakness, with respect to seedbank management, in the way weed seed defenses are constructed. Weed species with transient seedbanks appear to invest more in chemical defense than those species with highly persistent seedbanks. As a result, seeds in the latter category are relatively more dependent upon physical seed protection for persistence in the soil seedbank, and more vulnerable to management tactics that reduce the physical integrity of the weed seed coat.
The Effect of Postemergence Herbicides on the Spectral Reflectance of Corn
Authors: Everman Wesley J. , Medlin Case R. , Dirks Richard D. , Bauman Thomas T. , Biehl Larry
Published: September 2008

Studies were conducted in 2001 and 2002 to determine the effect of POST herbicides on the spectral reflectance of corn. POST corn herbicides evaluated included 2,4-D, atrazine, bromoxynil, dicamba + diflufenzopyr, nicosulfuron, and primisulfuron. Multispectral and hyperspectral data were collected and spectral properties were analyzed using SAS procedures and MultiSpec image analysis. Corn treated with POST applications of atrazine and primisulfuron could not be distinguished from nontreated corn regardless of data type or analysis method used. 2,4-D and dicamba + diflufenzopyr were the most readily distinguished from nontreated corn plots using both hyperspectral and multispectral data.
Creeping Bentgrass (Agrostis Stolonifera) Tolerance to Sulfosulfuron
Authors: McCullough Patrick E. , Hart Stephen E.
Published: September 2008

Sulfosulfuron was recently registered for grassy weed control in creeping bentgrass, but turf sensitivity is a concern for intensively managed golf courses. Field and growth chamber experiments in New Jersey investigated creeping bentgrass growth responses and tolerance to sulfosulfuron. Creeping bentgrass chlorosis increased with sulfosulfuron rate but turf had less chlorosis from sequential sulfosulfuron applications compared to bispyribac–sodium. Herbicide-treated turf had similar root weight compared to untreated turf on six sampling dates. In growth-chamber experiments, creeping bentgrass treated with sulfosulfuron had chlorosis and clipping weight reductions exacerbated by reductions in temperature from 25 to 15 C. Overall, creeping bentgrass appears to tolerate sequential sulfosulfuron applications better than or comparable to bispyribac-sodium in early summer, whereas creeping bentgrass sensitivity to sulfosulfuron increases at cooler temperatures.
Effects of Postemergence and Postemergence-Directed Halosulfuron on Triploid Watermelon (Citrullus Lanatus)
Authors: Dittmar Peter J. , Monks David W. , Schultheis Jonathan R. , Jennings Katherine M.
Published: September 2008

Studies were conducted in 2006 at Clinton and Kinston, NC, to determine the influence of halosulfuron POST (over the crop plant) or POST-directed (to the crop) on growth and yield of transplanted ‘Precious Petite’ and ‘Tri-X-313’ triploid watermelon. Treatments included a nontreated control, 39 g/ha halosulfuron applied POST-directed to 25% of the plant (distal or proximal region), POST-directed to 50% of the plant (distal or proximal; Precious Petite only), and POST. Watermelon treated with halosulfuron displayed chlorotic leaves, shortened internodes, and increased stem splitting. Vines were longest in the nontreated control (Tri-X-313 = 146 cm, Precious Petite = 206 cm) but were shortest in the POST treatment (Tri-X-313 = 88 cm, Precious Petite = 77 cm). Halosulfuron POST to watermelon caused the greatest injury (Tri-X-313 = 64%, Precious Petite = 67%). Halosulfuron directed to 25 or 50% (distal or proximal) of the plant caused less injury than halosulfuron applied POST. Stem splitting was greatest when halosulfuron was applied to the proximal area of the stem compared with POST-directed distal or POST. Internode shortening was greatest in treatments where halosulfuron was applied to the distal region of the stem. However, Tri-X-313 in the POST-directed 25% distal treatment produced similar total and marketable fruit weight as the nontreated control at Clinton. Fruit number did not differ among treatments for either cultivar. At Kinston, Precious Petite nontreated control and POST-directed 25% distal end treatment had greater marketable fruit weight than the POST-directed 50% proximal and POST treatments. The current halosulfuron registration allows POST application between rows or PRE. Limiting halosulfuron contact to no more than 25% of the watermelon plant will likely improve crop tolerance.
Efficacy of Residual And Non-Residual Herbicides Used in Cotton Production Systems When Applied with Glyphosate, Glufosinate, or MSMA
Authors: Price Andrew J. , Koger Clifford H. , Wilcut John W. , Miller Donnie , Van Santen Edzard
Published: September 2008

Field experiments were conducted to evaluate weed control provided by glyphosate, glufosinate, and MSMA applied alone or in mixture with residual and nonresidual last application (LAYBY) herbicides. Herbicide treatments included glyphosate early postemergence (EPOST) alone or followed by glyphosate, glufosinate, or MSMA late-postemergence (LPOST) alone or tank-mixed with one of the following LAYBY herbicides: carfentrazone-ethyl at 0.3 kg ai/ha, diuron at 1.12 kg ai/ha, flumioxazin at 0.07 kg ai/ha, fluometuron at 1.12 kg ai/ha, lactofen at 0.84 kg ai/ha, linuron at 0.56 kg ai/ha, oxyfluorfen at 1.12 kg ai/ha, prometryn at 1.12 kg ai/ha, or prometryn + trifloxysulfuron at 1.12 kg ai/ha + 10 g ai/ha. Residual herbicides were also applied alone LPOST. Weeds evaluated included barnyardgrass, broadleaf signalgrass, coffee senna, entireleaf morningglory, hemp sesbania, ivyleaf morningglory, johnsongrass, large crabgrass, Palmer amaranth, pitted morningglory, prickly sida, redroot pigweed, sicklepod, smooth pigweed, spiny amaranth, and velvetleaf. Treatments containing MSMA provided lower average weed control compared to those containing glyphosate or glufosinate, and residual herbicides applied alone provided inadequate weed control compared to mixtures containing a nonresidual herbicide. Across 315 of 567 comparisons (55%), when a LAYBY herbicide was added, weed control increased. The most difficult to control weed species at all locations was pitted morningglory. Barnyardgrass and hemp sesbania at the Mississippi location and hemp sesbania at the Louisiana location were collectively difficult to control across all treatments as well.
Residual Red Morningglory (Ipomoea Coccinea) Control with Foliar- and Soil-Applied Herbicides
Authors: Jones Curtis A. , Griffin James L.
Published: September 2008

Research was conducted to evaluate residual activity of herbicides applied postemergence (POST) and preemergence (PRE) for red morningglory control. Atrazine at 2.24 kg ai/ha controlled 30- to 60-cm red morningglory 78% 10 d after treatment (DAT) but control was greater for carfentrazone at 0.035 kg ai/ha, diuron plus hexazinone at 1.57 + 0.44 kg ai/ha, flumioxazin at 0.14 kg ai/ha, and sulfentrazone at 0.32 kg ai/ha (88 to 93%). At 28 DAT control with diuron plus hexazinone, flumioxazin, and sulfentrazone, reflective of both the initial POST control and soil residual activity, was equivalent to that of atrazine at 3.36 kg/ha (92%), but control was 34 to 66% with carfentrazone at 0.009, 0.018, and 0.026 kg/ha, hexazinone at 0.56 kg/ha, pyraflufen at 0.007 and 0.015 kg ai/ha, and trifloxysulfuron at 0.016 kg ai/ha. In another study to evaluate residual control with soil-applied herbicides, red morningglory was controlled at least 87% 35 DAT with atrazine at 2.24 kg/ha, diuron plus hexazinone at 1.57 + 0.44 kg/ha, flumioxazin at 0.14 kg/ha, sulfentrazone at 0.16 kg/ha, and metribuzin at 1.68 kg ai/ha. Control 35 DAT was 78% for atrazine at 1.12 kg/ha, 84% for diuron plus hexazinone at 1.05 + 0.30 kg/ha, and 63% for flumioxazin at 0.07 kg/ha. By 49 DAT only sulfentrazone controlled red morningglory 80% or more and by 63 DAT, control with sulfentrazone at rates of 0.21 kg/ha and higher was 83 to 88%. At 77 DAT sulfentrazone at 0.21 kg/ha controlled red morningglory 78% and no other herbicide treatment provided more than 46% control. In another study red morningglory control did not change from 49 to 63 DAT when sulfentrazone at 0.28 to 0.42 kg/ha was applied PRE following trifluralin preplant incorporated (PPI), but control decreased from 49 to 63 DAT when sulfentrazone was incorporated with trifluralin.
Yellow Nutsedge (Cyperus Esculentus) Control and Peanut Tolerance toS-Metolachlor and Diclosulam Combinations
Authors: Grichar W. James , Dotray Peter A. , Baughman Todd A.
Published: September 2008

Field studies were conducted in different peanut-growing areas of Texas during the 1999 through 2001 growing seasons to evaluate yellow nutsedge control and peanut tolerance to diclosulam alone applied PRE,S-metolachlor alone applied POST, or diclosulam applied PRE followed by (fb)S-metolachlor applied POST. Yellow nutsedge control was > 80% at five of six locations when diclosulam at 0.018 or 0.026 kg/ha applied PRE was fbS-metolachlor applied POST at 0.56, 1.12, or 1.46 kg ai/ha. Peanut stunting was noted with diclosulam at the High Plains locations but not at the Rolling Plains or south Texas locations. This stunting with diclosulam was due to a combination of peanut variety and high soil pH. Peanut yield was not always increased where yellow nutsedge was controlled.
Effect of Simulated Rainfall on Tall Fescue (Lolium Arundinaceum) Control with Glyphosate
Authors: Gannon Travis W. , Yelverton Fred H.
Published: September 2008

Field experiments were conducted to determine the effect of simulated rainfall after glyphosate application on tall fescue control. Three glyphosate formulations, three simulated rainfall amounts, two application rates, and three rain-free periods were evaluated. Glyphosate formulations evaluated included Roundup Original®, Roundup Pro®, and Roundup ProDry®. Herbicide drying periods, or rain-free intervals, included 15, 30, or 60 min. Simulated rainfall amounts were 0, 0.25, or 0.64 cm. Application rates of glyphosate were 3.4 or 6.7 kg ae/ha. Averaged across glyphosate formulation and simulated rainfall amount, excellent (≥ 90%) tall fescue control was observed when no simulated rainfall occurred within 60 min after application, whereas good (≥ 80%) tall fescue control was observed when 30 rain-free min were provided. Although current glyphosate labels are vague about rainfastness, these data indicate that critical rain-free periods may be as short as 30 min when higher application rates are used.
Response of Northeastern Arkansas Palmer Amaranth (Amaranthus Palmeri) Accessions to Glyphosate
Authors: Norsworthy Jason K. , Scott Robert C. , Smith Kenneth L. , Oliver Lawrence R.
Published: September 2008

Palmer amaranth accessions were collected from 21 fields in northeastern Arkansas in the fall of 2006 to determine if they differed in response to increasing doses of glyphosate and to determine the survival frequency following treatment with the label rate (870 g ae/ha). The herbicide dose required to kill 50% of individuals in an accession (LD50) ranged from 41 to 339 g/ha glyphosate, with most accessions responding similarly to glyphosate. The AR18 and AR19 were the least-sensitive accessions, with LD50rates of 312 and 339 g/ha glyphosate, respectively. The mean survival frequency was 2.2% across all accessions when 870 g/ha glyphosate was applied to five- to seven-leaf plants. Sixteen of the accessions had at least one plant survive glyphosate at 870 g/ha. AR18 and AR19 accessions had a survival frequency of 6.3 and 11.8%, respectively. Following an additional cycle of selection with glyphosate, 44.3% of the progeny from the AR19 accession survived glyphosate at 870 g/ha, and its LD50value significantly increased to 646 g/ha glyphosate. This research shows that there is a low percentage of Palmer amaranth plants currently present in production fields throughout northeastern Arkansas that are capable of surviving a single glyphosate application at the labeled rate and that further selection with glyphosate can increase the frequency of survival.
Impact of Irrigation and Hail on Palmer Amaranth (Amaranthus Palmeri) in Corn
Authors: Currie Randall S. , Klocke Norman L.
Published: September 2008

In 2005 a hailstorm struck a long-term dose–response study of irrigation requirements and corn plant populations. This misfortune occurred again in 2006 at approximately the same growth stage. Therefore, the objectives of the studies were redirected to measure the impact of actual hail events on corn leaf area index (LAI) and the competitive interaction of escaped Palmer amaranth populations induced by hail across different levels of irrigation and corn populations. In 2005, the study treatment with the lowest corn population and level of irrigation had twice the Palmer amaranth biomass (PABM) at corn harvest compared with the highest corn population and irrigation level. Corn LAI produced simple linear models that predicted both corn grain yield and PABM. In 2007, the nonhail year, PABM was depressed 4- to 15-fold compared with hail years. PABM declined linearly from 417 kg/ha at the lowest level of irrigation and corn population to 48 kg/ha at the highest level of irrigation and corn plant population. Although economic return per increment of irrigation declined in both hail years, the trends in economic returns were still positive. This suggests that a producer with similar conditions should continue to irrigate even though his or her rate of economic return is reduced.
Interaction of Glyphosate and Diquat in Ready-To-Use Weed Control Products
Authors: Wehtje Glenn , Altland James E. , Gilliam Charles H.
Published: September 2008

Glyphosate-based, ready-to-use weed control products frequently contain diquat (typically, 0.04 by weight relative to glyphosate) under the supposition that the diquat, “makes glyphosate work faster.” However, in light of the known modes of actions of glyphosate and diquat, we hypothesize that diquat may be antagonistic to glyphosate activity. Greenhouse experiments using longstalked phyllanthus were conducted to test this hypothesis. Glyphosate was applied at a series of rates, ranging from 0.11 to 1.12 kg ae/ha, either alone or tank-mixed with either 0, 0.02, 0.04, and 0.06 diquat. Onset of visual injury was more pronounced with the glyphosate + diquat tank mixtures compared with glyphosate alone. However, long-term control, as expressed by regrowth suppression, was greater with glyphosate alone. Regression analysis indicated that, at marginally effective glyphosate rates, the amount of glyphosate must be increased by approximately 60% to compensate for the diquat-based antagonism. Absorption and translocation studies using 14C-glyphosate revealed that the antagonism of diquat toward glyphosate can be attributed to reduced translocation of absorbed glyphosate.
Evaluation of Weed Control and Crop Safety with Herbicides in Open Field Tree Nurseries
Authors: Hanson Bradley D. , Schneider Sally A.
Published: September 2008

Open field production of fruit and nut-tree nursery stock depends upon preplant soil fumigation, extensive tillage, and hand-labor throughout the growing season for adequate weed control. Because methyl bromide, the favored fumigant, is being phased out because of environmental concerns and the costs of both fuel and labor continue to rise, herbicides are likely to become a more important weed management tool in the tree nursery industry. Two trials were conducted to evaluate weed control and crop safety with several herbicides applied following fumigation with methyl bromide or 1,3-dichloropropene in central California stone-fruit nurseries. PRE and POST-directed applications of several labeled and unlabeled materials were applied in a band over seeded peach rootstock or applied after emergence with a drop-nozzle spray boom. Crop productivity and weed control were monitored throughout the 1-yr growing season. PRE oryzalin and dithiopyr treatments provided the best weed control with very little crop injury. PRE applications of flumioxazin, rimsulfuron, and sulfentrazone did not have adequate crop safety at the rates and timings tested. However, POST-directed applications of flumioxazin and rimsulfuron were much safer to the peach and almond crops and should be evaluated in future trials. Additional herbicides and application techniques are needed to find acceptable, safe control measures for weeds, such as California burclover, common mallow, and redstem filaree, which often are poorly controlled with preplant fumigation in tree nurseries.
Transformation by Retroviral Vectors of Bone Marrow-Derived Mesenchymal Cells Induces Mitochondria-Dependent cAMP-Sensitive Reactive Oxygen Species Production
Authors: Piccoli Claudia , Scrima Rosella , Ripoli Maria , Di Ianni Mauro , Del Papa Beatrice , D'Aprile Annamaria , Quarato Giovanni , Martelli Maria Paola , Servillo Giuseppe , Ligas Claudio , Boffoli Domenico , Tabilio Antonio , Capitanio Nazzareno
Published: September 2008

Retroviral vectors are used in human gene therapy trials to stably introduce therapeutic genes in the genome of patients' cells. Their applicability, however, is frustrated by the limited viability of transformed cells and/or by risks linked to selection of oncogene-mutated clones. The reasons for these drawbacks are not yet completely understood. In this study, we show that LXSN-NeoR gene/interleukin-7-engineered mesenchymal stromal cells exhibited a marked enhancement of reactive oxygen species production compared with untransfected cells. This effect resulted to be independent on the product of the gene carried by the retroviral vehicle as it was reproducible in cells transfected with the empty vector alone. Stable transfection of mesenchymal stromal cells with the different retroviral vectors pBabe-puro and PINCO-puro and the lentiviral vector pSico PGK-puro caused similar redox imbalance, unveiling a phenomenon of more general impact. The enhanced production of reactive oxygen species over the basal level was attributable to mitochondrial dysfunction and brought back to altered activity of the NADH-CoQ oxidoreductase (complex I) of the respiratory chain. The oxidative stress in transfected mesenchymal stem cells was completely reversed by treatment with a cAMP analog, thus pointing to alteration in the protein kinase A-dependent signaling pathway of the host cell. Transfection of mesenchymal stromal cells with a PINCO-parental vector harboring the green fluorescent protein gene as selection marker in place of the puromycin-resistance gene resulted in no alteration of the redox phenotype. These novel findings provide insights and caveats to the applicability of cell- or gene-based therapies and indicate possible intervention to improve them.

Disclosure of potential conflicts of interest is found at the end of this article.
Evidence That an Early Pregnancy Causes a Persistent Decrease in the Number of Functional Mammary Epithelial Stem Cells—Implications for Pregnancy-Induced Protection Against Breast Cancer
Authors: Siwko Stefan K. , Dong Jie , Lewis Michael T. , Liu Hao , Hilsenbeck Susan G. , Li Yi
Published: September 2008

A completed pregnancy at a young age reduces a woman's lifetime risk of breast cancer by up to 50%. A similar protective effect of an early pregnancy has been observed in rodent models using chemical carcinogens. However, the mechanisms responsible for this protective effect remain unclear. Stem cells have been proposed to be the cells of origin for breast cancer. We hypothesized that an early pregnancy reduces adult levels of either mammary stem cells or mammary multipotent progenitor cells. Unsorted mammary cells from adult mice that had undergone an early parity had the same mammosphere formation efficiency as cells from age-matched virgin mice. However, when we transplanted adult mammary cells in limiting dilutions into cleared fat pads of syngeneic mice, we found a significant reduction in the outgrowth potential of the cells from early parous mice compared with age-matched virgin mice. The extent of fat pad filling in successful outgrowths did not change, suggesting that although mammary stem cells in parous mice retained their functional competence, the number of mammary stem cells was reduced. Our results provide the first direct evidence that an early pregnancy has an effect on mammary stem cells.

Disclosure of potential conflicts of interest is found at the end of this article.
A Developmentally Regulated Heparan Sulfate Epitope Defines a Subpopulation with Increased Blood Potential During Mesodermal Differentiation
Authors: Baldwin Rebecca J. , ten Dam Gerdy B. , van Kuppevelt Toin H. , Lacaud Georges , Gallagher John T. , Kouskoff Valerie , Merry Catherine L.R.
Published: September 2008

Heparan sulfate (HS) is a mandatory coreceptor for many growth factors and morphogens involved in embryonic development; its bioactivity is dictated by complex sulfation motifs embedded within the polymer chain. Using a panel of HS-specific antibodies we have identified a unique HS epitope recognized by antibody HS4C3 that is selectively expressed during differentiation of embryonic stem (ES) cells along the mesodermal lineage to the hemangioblast stage. The appearance of this high-affinity HS4C3-binding (HS4C3high) epitope is transient; the epitope is specifically expressed within the emerging Brachyury+ (Bry+) population and marks those cells that will become fetal liver kinase 1 (Flk1)+. Fluorescence-activated cell sorting (FACS) separation and colony forming assays revealed that HS4C3high/Flk1+ cells have a dramatically increased potential to form both blast and endothelial colonies, both of which depend upon the HS-binding growth factor vascular endothelial growth factor. Critically, expression of this HS epitope is tightly regulated, disappearing from the cell surface as the resultant hematopoietic lineages mature, in a similar manner to protein markers Bry and Flk1. In vivo studies showed a remarkable correlation with in vitro findings, with expression of HS4C3-binding epitopes restricted to newly formed mesodermal tissues during gastrulation. We believe this is the first time a defined HS epitope has been implicated in a specific developmental pathway and that this provides, in addition, a novel enrichment technique for the isolation of hemangioblasts from mixed differentiated ES cell cultures.

Disclosure of potential conflicts of interest is found at the end of this article.
Hedgehog Signaling Regulates Brain Tumor-Initiating Cell Proliferation and Portends Shorter Survival for Patients with PTEN-Coexpressing Glioblastomas
Authors: Xu Qijin , Yuan Xiangpeng , Liu Gentao , Black Keith L. , Yu John S.
Published: September 2008

The identification of brain tumor stem-like cells (BTSCs) has implicated a role of biological self-renewal mechanisms in clinical brain tumor initiation and propagation. The molecular mechanisms underlying the tumor-forming capacity of BTSCs, however, remain unknown. Here, we have generated molecular signatures of glioblastoma multiforme (GBM) using gene expression profiles of BTSCs and have identified both Sonic Hedgehog (SHH) signaling-dependent and -independent BTSCs and their respective glioblastoma surgical specimens. BTSC proliferation could be abrogated in a pathway-dependent fashion in vitro and in an intracranial tumor model in athymic mice. Both SHH-dependent and -independent brain tumor growth required phosphoinositide 3-kinase-mammalian target of rapamycin signaling. In human GBMs, the levels of SHH and PTCH1 expression were significantly higher in PTEN-expressing tumors than in PTEN-deficient tumors. In addition, we show that hyperactive SHH-GLI signaling in PTEN-coexpressing human GBM is associated with reduced survival time. Thus, distinct proliferation signaling dependence may underpin glioblastoma propagation by BTSCs. Modeling these BTSC proliferation mechanisms may provide a rationale for individualized glioblastoma treatment.

Disclosure of potential conflicts of interest is found at the end of this article.
OCT4 Spliced Variants Are Differentially Expressed in Human Pluripotent and Nonpluripotent Cells
Authors: Atlasi Yaser , Mowla Seyed J. , Ziaee Seyed A.M. , Gokhale Paul J. , Andrews Peter W.
Published: September 2008

OCT4 is a master regulator of self-renewal in embryonic stem cells and can potentially encode two spliced variants, designated OCT4A and OCT4B. We have examined the expression pattern of these OCT4 isoforms in various human pluripotent and nonpluripotent cells. Our data revealed that whereas OCT4A expression is restricted to embryonic stem (ES) and embryonal carcinoma (EC) cells, OCT4B can be detected in various nonpluripotent cell types. Furthermore, we detected a novel OCT4 spliced variant, designated OCT4B1, that is expressed primarily in human ES and EC cells and is downregulated following their differentiation. We also found a significantly higher level of OCT4B1 expression in stage-specific embryonic antigen-3 (SSEA3)(+) compared with SSEA3(−) subpopulations of cultured ES cells. Taken together, our data demonstrated a distinctive expression pattern for OCT4 spliced variants in different cell types and highlight the necessity of defining the type of OCT4 when addressing the expression of this gene in different human cells.

Disclosure of potential conflicts of interest is found at the end of this article.
The role of redox signaling in cardiac hypertrophy induced by experimental hyperthyroidism
Authors: Araujo A S R , Schenkel P , Enzveiler A T , Fernandes T R G , Partata W A , Llesuy S , Ribeiro M F M , Khaper N , Singal P K , Belló-Klein A
Published: September 2008

This study was conducted to test whether oxidative stress activates the intracellular protein kinase B (AKT1) signaling pathway, which culminates with cardiac hypertrophy in experimental hyperthyroidism. Male Wistar rats were divided into four groups: control, vitamin E, thyroxine (T4), and T4+vitamin E. Hyperthyroidism was induced by T4 administration (12 mg/l in drinking water for 28 days). Vitamin E treatment was given during the same period via s.c. injections (20 mg/kg per day). Morphometric and hemodynamic parameters were evaluated at the end of the 4-week treatment period. Protein oxidation, redox state (reduced glutathione, GSH/glutathione dissulfide, GSSG), vitamin C, total radical-trapping antioxidant potential (TRAP), hydrogen peroxide (H2O2), and nitric oxide metabolites (NOX) were measured in heart homogenates. The p-AKT1/AKT1 ratio, p-glycogen-synthase kinase (GSK)3B/GSK3B ratio, FOS, and JUN myocardial protein expression were also quantified by western blot after 4 weeks. Increases in biochemical parameters, such as protein oxidation (41%), H2O2 (62%), and NOX (218%), and increase in the left ventricular end-diastolic pressure were observed in the T4 group. T4 treatment also caused a decrease in GSH/GSSG ratio (83%), vitamin C (34%), and TRAP (55%). These alterations were attenuated by vitamin E administration to the hyperthyroid rats. Expression of p-AKT1/AKT1, p-GSK3B/GSK3B, FOS, and JUN were elevated in the T4 group (by 69, 37, 130, and 33% respectively), whereas vitamin E administration promoted a significant reduction in their expression. These results indicate that oxidative stress plays an important role in cardiac hypertrophy, and suggest redox activation of AKT1 and JUN/FOS signaling pathways with H2O2 acting as a possible intracellular mediator in this adaptive response to experimental hyperthyroidism.
Dewatering of reservoir sediment slurry using woven geotextiles. Part I: Experimental results
Authors: Huang C.-C. , Luo S.-Y.
Published: September 2008

A series of falling-head dewatering column tests (FHDT) was performed using a mixture of water and reservoir sediment and four types of woven geotextile to investigate the factors that control the permeability and piping of underdrainage dewatering systems such as geotextile containers and dewatering ponds. Some conventional criteria for the filter selection were also examined. It was found that the permeability of the geotextile dewatering system is characterized by the thickness and the void ratio of the filter cake that progressively deposits upstream of the geotextile. The filter cake exhibited a normally consolidated state with a compression index of 0.7, and the height of the potential filter cake can be predicted based on the total suspended solids and the void ratios measured in the present study. It was also found that the conventional soil retention and clogging criteria should be reformulated for the geotextile dewatering system to take into account some fundamental aspects of the system that were ignored in these existing criteria.
Abrasion damage of a woven geotextile due to various gravelly flows
Authors: Huang C.-C. , Tzeng Y.-S.
Published: September 2008

This study investigated some factors influencing the abrasion damage to a woven geotextile using a circular turbid flow chamber test system. Two uniformly graded aggregates composed of different minerals and angularities were used in the turbid flow test. Two important factors—particle concentration and flow velocity—were also investigated. It was found that the percentage of ultimate strength loss (PSR) due to abrasion damage was linearly related to these parameters and to the Los Angeles percentage weight loss, regardless of the particle size and angularity examined in this study. It was also found that the Rt method, which uses an average gradient (Rt = 18% per logarithmic cycle of test duration T) for the PSR-log T relationships obtained for T = 8 h, is potentially useful in predicting the values of PSR for relatively long test durations. The above findings are valid only for the limited test conditions investigated, and should be confirmed on the basis of comprehensive test results regarding the effect of size, hardness and shape of aggregate.
Gas transmissivity at the interface of a geomembrane and the geotextile cover of a partially hydrated geosynthetic clay liner
Authors: Bouazza A. , Vangpaisal T.
Published: September 2008

The migration of gas through a geomembrane overlying a geosynthetic clay liner in a composite landfill cover is primarily a result of the flow through defects in the geomembrane. The nature of the contact conditions between the GCL and the geomembrane is of paramount importance if the leakage rate of a GCL/GM composite barrier with a defect in the geomembrane needs to be assessed effectively. The present paper reports on interface gas transmissivity measured in a specially made cell. It was found that the gas transmissivity ranged between 2 × 10−7 m2/s and 4.5 × 10−7 m2/s for the range of moisture content and differential gas pressure investigated. This corresponded to a reduction of approximately 40% in the gas transmissivity when the moisture content increased from essentially dry to 120%.
Cold temperature testing of geotextiles: new, and containing soil fines and moisture
Authors: Henry K. S. , Durell G. R.
Published: September 2008

A test program examined the behavior of geotextiles at very low temperatures, and tested the hypothesis that the presence of soil fines and moisture would result in decreased strength values compared with geotextiles at cold temperatures. Wide-width strip tensile and static puncture tests were performed on needle-punched nonwoven polypropylene geotextiles at 20°, 0°, –20°, –40° and –54°C for the wide-width strip tests and at –51°C for the puncture tests on new specimens and specimens that contained soil and moisture. At all sub-freezing temperatures, the specimens that contained ice and soil were much stronger and more brittle in tension than the new specimens. Soil and moisture did not significantly influence puncture strength.
Temporal trends of mercury, cesium, potassium, selenium, and thallium in arctic char (Salvelinus alpinus) from Lake Hazen, Nunavut, Canada: Effects of trophic position, size, and age
Authors: Gantner Nikolaus , Power Michael , Babaluk John A. , Reist James D. , Köck Günter , Lockhart Lyle W. , Solomon Keith R. , Muir Derek CG.
Published: September 2008

Arctic char (Salvelinus alpinus L.), the top predator in High Arctic lakes, often is used as a bioindicator of Hg contamination in Arctic aquatic ecosystems. The present study investigated effects of trophic position, size, and age of Arctic char in Lake Hazen, the largest lake in the Canadian High Arctic (81°50′N, 70°25′W), on Hg bioaccumulation. In addition, several essential (Se, K) and nonessential elements (Tl, Cs) in char muscle tissue were examined to compare their behavior to that of Hg. Trophic position of Arctic char was identified by stable isotope (δ15N) signature. Temporal trends of Hg from seven sampling campaigns over a 16-year period (1990–2006) were investigated for the overall data and for one trophic class. Concentrations of Hg were not correlated with age but were positively related to fork length and trophic position. Large char with greater δ15N signatures (>12‰) had larger Hg concentrations (0.09–1.63 μg/g wet wt) than small char with smaller δ15N signatures (<12‰, 0.03–0.32 μg/g wet wt), indicating that Hg concentrations increased with trophic position. Nonessential Cs and Tl showed relationships to age, length, and trophic position similar to those of Hg, indicating their potential to bioaccumulate and biomagnify. Essential Se and K did not show these relationships. Concentrations of Hg were adjusted using δ15N, leading to less within-year variability and a more consistent temporal trend. The δ15N-adjusted trend showed no decline of Hg in Arctic char from Lake Hazen (1990–2006) in the overall data set and in the small morphotype. Trends for the same period before the adjustment were not significant for the overall data set, but a slight decrease was apparent in the small morphotype. The results confirm the need to consider trophic position and fish size when monitoring temporal trends of Hg, particularly for species with different morphotypes.
Comparative Evaluation of Different Pretreatments on Tomato Slices Dried in a Cabinet Air Drier
Authors: Joshi Neena , Gariepy Yvan , Raghavan GS Vijaya
Published: September 2008

Effects on drying and other acceptability parameters when slices of tomatoes were subjected to different pretreatments before initiating the process of drying were studied. The study also included observation of effects of inherent moisture levels in the drying tomato on the attributes such as color, texture, shrinkage and appearance. The pretreatments consisted of solutions in water, of sugar (1%), calcium chloride (1,2 % ), common salt (2%), ascorbic acid (0.75%) and sodium benzoate (0.1%). The slices of tomato, 1 cm thick, were soaked in the specific solutions separately for 3, 6 and 12 hours. Untreated tomato slices served as control. Drying was stopped when tomato slices attained moisture levels of 30% and 10%. Drying rate (mr = m ebx where: mr - moisture ratio; m - model constant; b - drying rate; x  time, minute) ranged between -0.007 (sugar solution 1%) and -0.029 (control). Pretreatments did in fact influence the shrinkage both at 10 and 30 % moisture levels. Effect on shrinkage was more pronounced at 30 % than 10 % moisture level. Visual assessment and photographs suggest that pretreatments with calcium chloride and sodium chloride had better texture and visual appeal than other pre-drying treatments. Duration of drying to reach 10% moisture level ranged between 180.0 and 241.67 minutes. Variations were observed between samples for parameters re-hydration ratio and water activity (0.462  0.550). It is suggested that pre-drying treatments do affect the different parameters that were studied and can help in improving the visual appeal and acceptability.